Monday, September 30, 2019

Reconstruction and African Americans from 1865-1900

Reconstruction and African Americans from 1865-1900 From 1865 to 1900, Reconstruction was meant to help change the lives of African Americas. However, because of prejudice, Reconstruction didn’t go on as far as it could have. Reconstruction tried to deliver its promises to African Americans while battling a discriminatory white America. This is seen socially, through civil rights, and politically, through Jim Crow Laws and voting. Concerning social promises, Reconstruction made astounding changes for African Americans; this is evident in newspapers and the Civil Rights Act of 1875.White Americans were becoming more sympathetic to the needs of African Americans, or at least white reporters were. Newspapers began to print stories and pictures made to draw sympathy to the black man and anger towards the KKK, such as in Harper’s Weekly’s â€Å"One Less Vote† (Doc A, F). The Civil Rights Act of 1875 allowed each citizen equality, no more segregation in hotels, restaurants, public theaters, etc. , but it wasn’t followed by everyone. Business owners were not willing to de-segregate, and the ones who were willing lost white business.White men and women remained biased, making it impossible for African Americans to have equality. White bias didn’t stop the American government from taking political action to protect African Americans. The 14th and 15th Amendments attempted to stop discrimination; the 14th Amendment gave protection of privileges for blacks and the 15th Amendment gave them the right to vote. Because of reforms, African Americans were legally allowed to vote. This brought celebration in African American communities, now they could have political influence. However, mainly in the South, blacks were threatened and even killed for going to vote.Opposing government reforms, such as the Amendments, was the Deep South. The Jim Crow Laws were passed; by segregation, prohibiting people to even talk about equality, and inter -racial marriage, equality was outlawed. Socially there was more acceptance. Politically there was more freedom. Reconstruction did alleviate many of the African Americans’ burdens. Overall, Reconstruction during 1865 to 1900 could have gone much farther. If it were not for the hostility expressed towards the equality of the races, Reconstruction could have quickly given the blacks their freedoms.

Sunday, September 29, 2019

Cause and Effect Essay Example Essay

What is the leading cause of death in the U.S.? Many people would guess cancer, but they would be wrong. The leading cause of death over the past few years has been heart disease. Last year, heart diseases claimed the lives of more than 600,000 Americans. The most common of these is acute myocardial infarction, better known as a heart attack. Each year, about 720,000 Americans suffer from a heart attack. That averages to almost two thousand heart attack cases a day! So why are there so many heart attacks? The answer is simple: by eating unhealthily, not exercising, and smoking, millions of people put themselves at risk of suffering a heart attack. One of the main causes of a heart attack is an unhealthy diet. Because eating healthily costs more, people turn to cheap fast food instead. This fast food is loaded with cholesterol, an important lipid used in the membranes of cells. However, if a person eats too much cholesterol, the excess begins to build up along the wall of the person’s arteries. This substance, called plaque, inhibits the flow of blood to the heart. Consequentially, the heart has to pump much harder to circulate the blood. An unhealthy diet also leads to high blood pressure which further increases the build up of plaque and other fatty matter in the arteries. All of this plaque causes decreased blood flow to the heart which makes it weaker. Although the decreased flow of blood can cause heart problems later on, the real danger is the risk that a piece of the plaque could break off, leaving a gap. If this happens, red blood cells form a clot on top of the plaque which could result in the blockage of the entire artery, causing a heart attack. Maintaining a healthy diet is one of the best ways to lower the risk of having a heart attack. Another factor that increases the risk of having a heart attack is lack of exercise. The heart is a muscle and like any other muscle, it becomes stronger by exercising. Sadly, many people do not and the heart stays weak. It does not pump as well, leading to decreased capability in the future, and numerous health problems. Exercising also prevents clotting in the arteries, therefore lowering the chances of having the arteries blocked. Lazy people who sit and watch television all day miss out on this benefit, and increase the likelihood of a heart attack. Finally, exercise reduces inflammation in the arteries, optimizing blood flow and reducing the threat of a heart attack. Unfortunately, many people do not take the time to exercise, and they suffer from poor blood flow, inflammation of the arteries, and increased risk of heart problems. By not exercising, people put themselves in danger of suffering a heart attack. Finally, countless heart attacks are caused by smoking. Surprisingly, about one in every five deaths from heart disease is caused by smoking. Everybody knows that smoking leads to breathing issues and lung cancer, but what most people do not realize is that smoking also puts people at a higher risk of having a heart attack. The 4,000 or more poisonous substances in a cigarette harm blood vessels throughout the body, including the heart. They also increase the likelihood of blood clots in the arteries which cause heart attacks. Next, smoking causes the arteries to narrow which reduces blood flow further. This means that it does not take as big of a clot to cause a heart attack. Lastly, the carbon monoxide breathed in from smoking replaces the oxygen that would have been breathed in. The carbon monoxide then binds to the red blood cells and is distributed to the body instead of oxygen. This poisons the whole body, including the heart, and makes it have to do more work to supply the body with oxygen. By smoking these lethal substances, people put themselves in the clutches of the leading cause of death in the world. In a society where the fast-food industry booms, video games replace exercise, and cigarettes litter the streets everywhere, it is not surprising that so many people have heart attacks each year. Many people choose to eat unhealthily, lounge around all day, and smoke, endangering their overall health and putting themselves at risk of a heart attack. However, people always have a choice. Although all these things can cause a heart attack, they are not really the underlying problem. The irresponsible behavior and foolish decisions of people is really behind the leading cause of death in America.

Saturday, September 28, 2019

Logistic Planning

Logistic planning and management largely focus on lowering the cost associated with producing and distributing products under a variety of constraints. Logistics can be meant in different aspects of terms. In the perspective of Customer, the definition is getting the right product, to the right customer, in the right quantity, in the right condition, at the right place, at the right time and at the right cost. In the perspective of utility and value, the definition is providing the time and place utility/value of materials and products in support of organization objectives.In the perspective of Functional Management, the definition is provide materials requirements determination , purchasing , transportation , inventory management, warehousing, materials handling, industrial packaging, facility location analysis, distribution, return goods handling, information management, customers service, and all other activities concerned with supporting the internal customer (manufacturing) with materials and the external customer(retail stores) with product.Citied from Stephen H. Russell, â€Å"A General Theory of Logistic Practices. Logistic is the support of producing products in order for marketers to market the product. An example describing my statement will be that in order to sell laptops to customers, the logistics management would gather the products and send to retailers for sale. This operation is an important task. † Logistic is the support of producing products in order for marketers to market the product. An example describing my statement will be that in order to sell laptops to customers, the logistics management would gather the products and send to retailers for sale. This operation is an important task.

Friday, September 27, 2019

Conceptual Analysis Assignment Example | Topics and Well Written Essays - 1250 words

Conceptual Analysis - Assignment Example If one has to love, it might be necessary not to ask something in return and it is a decision to take for this matter. Therefore, it is possible to see unrequited love at some point, as long as there are individuals who will decide to love even if they will not be loved in return. On the other hand, love does not inherently involve sexual attraction. For this matter, we can always go back to our major premise that love is a decision to take and part of it is to go for it even if there is no sexual attraction involved. Since love is a decision, one can therefore love with more than one person at a time or over a lifetime. Finally, although love is linked to survival and reproduction, but knowing it is a decision, then one can still decide to love even if it is beyond the context of continued existence and propagation. Now, let us move our discussion to unveil sufficient condition on what does it mean to really be in love. Sufficiently, we can say that one is really in love when he or she is able to express that feeling from within, by which it is a form of engagement or personal attachment to whoever such expression has to be given. The expression involved in this case can be verbal, non-verbal or both. In the presence of this verbal, non-verbal or both requirements, love can be manifested and it is a sufficient condition to consider that there exists an opportunity to show what love is. Although actions may speak louder than words, these two requirements are relevant expressions that one can employ individually or both in order for us to determine what it means to really be in love. Therefore, the act of showing love is manifested through verbal and non-verbal gestures as substantial evidence for its actual expression. For instance, if a man gives flower to a woman because he loves her may not sufficiently convince us that he really indeed loves her. However, further necessary expressions is needed to prove this, and here where we can probably depict a combinat ion of the needed requirements, verbally and non-verbally. Now that we have finally formulated the necessary and sufficient conditions in order to know what it means to really be in love, we are heading to discuss the intended Socratic definition for this matter. Concerning this, we can therefore say that an individual is in love when he or she is performing a decision to do it, by which we can actually depict through verbal and non-verbal acts or both as the sufficient requirements. Section B. Conceptual Analysis II: Love In Section A, we have introduced the necessary condition for the realization of love, which is a form of decision to take. To sufficiently prove this, expressions such as verbal and non-verbal or both as the requirements must be depicted. Therefore, we can define that an individual is in love when he or she is performing a decision to do it, by which we can actually depict through verbal and non-verbal acts or both as the sufficient requirements. Socrates might re fute this claim by providing substantial counter examples, so as to nullify the entire concept by providing an instance that may potentially defy it. For this reason, here are the potential counter examples that Socrates might probably use against the established definition above. Socrates might use the concept of commitment as necessary element linked to love. Therefore, without this commitment, which is something one could sufficiently observe, then there is no existence of love at all. At some point,

Thursday, September 26, 2019

Do Abrahamic Religions (Judaism, Christianity, and Islam) Cause War Research Paper

Do Abrahamic Religions (Judaism, Christianity, and Islam) Cause War - Research Paper Example However, there are differences in the beliefs and systems that Jews, Christians and Muslim accept as legitimate. Jews hold that the Abrahamic covenant was carried down onto Isaac (Abraham's second son) and then to Jacob (Isaac's second son) and then down to Jacob's (also known as Israel's) descendants. After years of the Israelite community growing, they merited to receive the Torah, a set of Laws given directly to the Israelites through Moses. The Jews hold the Torah (first five books of the Bible) to be authoritative and the generational interpretation of the Torah from the Prophets to the Rabbis as absolutes (Idel 7). Christianity on the other hand sprouted out of Judaism because the followers believed that Jesus Christ was the son of God and this was a position that most Jews rejected and never accepted. On the other hand, Christians also did not accept the generational interpretation of the Torah as Jews did but rather focused on the life of Jesus Christ as an ideal standard interpreted by the New Testament. Islam on the other hand came up as a result of revelations received by Mohammed, a descendant of Abraham through the line of his first son, Ishmael (Schmidt-Leukel 149). Although there are clear areas that Islam seems to build on Judaism and Christianity, Islam also maintains its distinct features and elements. Islam, Christianity and Judaism cuts across elements of spirituality, morality and nationalism (Oystein, 72). In terms of spirituality, all these Abrahamic Faiths profess some element of control over the supernatural and promises humanity a pleasant life after death. Additionally, these promises comes with some responsibilities that seek to make people live according to some standards and ideals prescribed by these religions. The Jewish have a set of traditions Halackha that must be adhered to at all times in a person's life. Christians have doctrines and principles of holiness that must be followed. Muslims also have the Sunnah which sums up the traditions and instructions a s revealed to Prophet Mohammed. The institutionalization of these principles and practices amongst a group of people professing each of these three Faiths leads to the nationalism aspect of the Abrahamic Faiths. This requires the establishment of the structures of a modern nation, including a military that would protect the interest of a religious state. Based on this, I identify three main issues of misunderstanding and misuse of the Abrahamic religions that led to wars and various forms of violence throughout history. These three matters include the rise of opportunistic leaders in the original kingdoms of the founders of these

The Likelihood of Success That Halliburton Can Achieve Essay

The Likelihood of Success That Halliburton Can Achieve - Essay Example There is an increasing concern among corporate houses to manage the current and the emerging issues that are being faced by them. This is required in order to create an effective management and maintain a competitive edge over its competitors. If the issues are not resolved by the management in a timely manner then this is likely to impact the financial performance of the company and raise the question of the credibility of the corporate governance. The most important task of the management is to identify the prioritized critical issues that are being faced by the organization. The effectiveness of resolving the issues depend on the identification of the problems and allocation of the top management in resolving that issue. Corporate scandals have an immense impact on the credentials of a business. The past decade had witnessed a major increase in the rate of the corporate scandals which had significantly impacted the profitability of a business. Corporate scandals have become an imp ortant source of loss of investor confidence in the company. A root cause of this failure has been identified in the â€Å"command and control† nature of these corporations which follows a top-down approach to management with a single board dictating the policies. Owing to these complex procedures that raise the chances of corporate scandals, organizations are now being increasingly forced to adopt a simpler managerial structure that is guided by flexibility. This is essentially a secondary research that will use data from secondary resources and interpret the problems that have been faced by the company and the way in which it has been successful or unsuccessful in handling the issues. The report tries to analyze the likelihood of success that Halliburton can achieve. This report will use the academic framework of SWOT to identify the issues that are being faced by Halliburton.

Wednesday, September 25, 2019

Relevance of Individualism in Life Today Essay Example | Topics and Well Written Essays - 1000 words

Relevance of Individualism in Life Today - Essay Example Individuals past thoughts, decisions, and achievements as a success following self-reliance are different as time goes on whereby, other factors contribute towards individualisms such as sociology, western civilization, education, and region. These factors may limit individual’s self-reliance; hence, ideas from a specific person are limited in the society. However, the authors of the articles clearly indicate that is an important virtue in individuals’ lives today.Education is an important aspect of the life of individuals not only on the career perspective but also in recognition of personal weakness and strength in life, which eventually enhances individualism today in a positive way. In the essay of Emerson about self-reliance, it is evident that once a man gets educated, the sense of ignorance of own thoughts in life eventually reveals; hence an individual is able to accept the previous mistakes done because of ignorance. Notably in individuals’ life, it has been observed that ignorance is not because of illiteracy rather it is revealed by literacy for example an individual may ignore the effect of having unprotected sex due to friends influence but once educated on the effects associated, it helps to prevent any future incidence whereby individualism decision will prevail over the peer pressure. This indicates that education enhances individualism today in such a way that through the experiences and required knowledge in life, an individual thinks on his own for his own welfare and decision-making. making. Self-View And the World View In Relation To Individualism Toady The world has different views towards an individual’s problems and achievements with those that the specific person has on

Tuesday, September 24, 2019

Innovation in nursing Discussion board phase Assignment

Innovation in nursing Discussion board phase - Assignment Example This was a three times increase from the amount that had been channeled by 2009, which is a huge marker of progress in the American healthcare. Innovation in the American healthcare is vital and paramount. Two uses of innovation in healthcare can be derived from two conditions in the health status of the American population. To begin with, there is a financial pressure and squeeze on the healthcare industry, especially from the Affordable Care Act. The providers of healthcare are thus in dire need of creative strategies, ideas and innovations that can enable them keep on delivering high quality healthcare to the American population (Omachonu, 2010). Given the conditions, technological innovation is the most viable chance that they have. Secondly, combined with the cost of care is the aging population and dynamic changes in dietary practices of the American population, and lifestyles of people which expose them to deadly health conditions such as chronic diseases, obesity, heart diseases and diabetes. This, as Porte and Teisberg (2013) collectively note, results to a very big increase in volume of patients who require attention from the nurses. Innovations that will address the above two issues are therefore paramount, and although getting an innovation to be adopted is still a great challenge, it is very important for healthcare institutions to adopt the many available innovations. In addition to the above two, mobile and digital cloud technologies promise an improved health quality and patient care, especially with the ability to provide vital patient care and updated information, and as a result, even physicians have a chance to become better and more efficient (Porter and Teisberg, 2013; Omachonu, 2010). A personal health record that is electronic would be a wise choice in improving the quality of patient care. Such a platform would enable patients and other consumers to share their personal information concerning their health

Monday, September 23, 2019

An overview to the main causes of delays and disruption to large scale Essay

An overview to the main causes of delays and disruption to large scale projects during Initiation and Planning at state of Qatar - Essay Example st all of the previous studies focused only on general causes of project delays at the level of the whole project, or mainly on the implementation phase where the problems come to the fore and impact upon completion. Therefore the present study will make an important and individual contribution to the project management field and explore ways of minimizing the causes and factors of delays, with a focus on the earlier stages and the way the project is conceived by all parties, rather than looking just at specific issues in the later stages. The field of project management has been growing exponentially in recent years, with contributions from multiple discipline areas which use ideas and data from both academics and practitioners. This makes it difficult for even expert project managers to find their way through the multiple theories and approaches that are available. For the purposes of the present study, however, there is a focus on the main issues and causes of delays and disruption, which often occur in mega construction projects. Very often the scholarly literature, and especially the practitioner reports, emphasize the effects or consequences of such issues, but in this case the initial causes are selected as the main point for analysis. These issues can arise at any stage of a project but they often have their roots somewhere early in the process of setting up and starting the project. The purpose of this literature review is therefore to examine the theory and practice of project management with an emphasis on the initiation and planning stages, and the causes of delays and disruption which can occur at any stage. This approach ensures that the literature review provides a sound and comprehensive basis for an investigation into several recent and contemporary projects in Qatar. It highlights highlighted how past experiences with delays and disruptions relate to project management theory and suggested what specific problems may arise in the Qatari context.

Sunday, September 22, 2019

Elaine Cumming and Warren Earl Henrys Disengagement Theory Essay Example for Free

Elaine Cumming and Warren Earl Henrys Disengagement Theory Essay Disengage because of reduced physical health and loss of social activities * Cummings (1975) argued that older people would experience a reduction in social contact as they grow older and becoming increasingly ‘individual’ * ‘disengaging is a natural part of aging’ *   Everyone expects death, and ones abilities will likely deteriorate over time. As a result, every person will lose ties to others in his or her society. aging  is an inevitable, mutual withdrawal or disengagement, resulting in decreased interaction between theaging  person and others in the social system he belongs to. Embardos disagreement.. * Said theory was discredited for many reasons * Argues that majority of older people remain socially involved with family and friends . Maybe choose to spend more time with people they are close to rather than seeking new friends * Current data from the office for national statistics supports the view that a majority of older people enjoy social networks * if people only interact with close friends does this mean they are disengaged? * Argued that older people need to disengage but * They need to remain ‘active’ in order to stop disengagement going too far * Argues that society should provide older people with activities * Society should provide them with education of how to make use of the activities * It is very important for older adults to remain mentally active and maintain an interest in life and enjoy the company of others * The theory assumes that a positive relationship between activity and  life satisfaction| M2 – case study 1 Alan is a 76 year old man who has recently lost his wife. He is completely disengaged. He does not try to socialise as he is still grieving from the loss of his wife and can’t seem to pull himself around. Firstly the social disengagement theory will affect Alan’s social development; he is disengaging himself from any social activities or communications as he is grieving. This will have a negative effect on his social and emotional development as he is not talking to people to help him feel better or to get things ‘off his chest’, keeping it all locked away. This will have a negative effect and will make him a lot worse. It may also have a negative effect on his physical or physiological development as he may be susceptible to depression. This may lead to physical harm. The argument against this theory will however have a positive effect on Alan as he will be socialising with other people, helping tae his mind off the loss of his wife. He will also be engaging in social activities keeping his mind active positively effecting his intellectual development, and again taking his mind off his loss. The argument to this theory would also have a positive effect on his physical development as he will be getting around more when joining in activities. Lastly joining these activities will reflect on Alan’s emotional development and maybe help him to cope with his loss more as he is not constantly grieving over it. Bromleys activity theory would have a positive effect on Alan’s, physical, intellectual, social and emotional development. As the theory states, older people should be provided with activities and educated on these topics, this will help Alan’s intellectual development as his mind is still active, as he is gaining knowledge about the activities given and his brain will be engaging in the activities keeping it active also. This will also have a positive effect on Alan’s physical development as he will be taking part in the activities, enabling him to get around and be more fit and active. His social development will be effected greatly also as he will be constantly communicating with a lot of different people. Lastly his emotional development will be effected as he may cope with his loss a bit more successfully, and he may also discover a hobby he has taken a liking to. Case study 2 Geena is 86 years old and struggles to move around a lot. She is very upset that her mobility isn’t as strong as it used to be, and gets emotional at times when she tries to do something independently and cannot. Although she is independent she does not like being alone. As Geena is a very independent woman, the social disengagement theory has a negative effect on her physical development as it states, she is disengaged because her restricted mobility to get around. Not only does this affect her social development, but her physical too as she is straining herself to complete tasks that are difficult for her. This also has a negative effect on her emotional development as it upsets her that she cannot complete daily things she feels she needs to do. This does not affect her intellectual development. The disagreement to this theory would not affect Geena a lot as she is not disengaged. However it would affect her intellectual development positively if she joined a social networking site, as this would build up her knowledge of technology, effecting her social life also as she may get in touch with some old friends. This will not affect her emotional or physical development. Bromleys activity theory may affect Geena’s emotional development negatively as she has restricted mobility and would not be able to join any physical activities without becoming distressed and upset. However, if she joined activities such as bingo this would positively affect her social development as she would get out more an interact with a variety of different people, it would positively affect her emotionally as she will be able to complete activities without having to move or becoming distressed and upset about it. Lastly it will positively affect her intellectually as it will be keeping her mind active while she is concentrating on her activities.

Saturday, September 21, 2019

Integrated Community Centre for Mental Wellness in Hong Kong

Integrated Community Centre for Mental Wellness in Hong Kong Introduce ICCMW Services in Hong Kong Integrated Services in Hong Kong Start from 1991, the establishment of first integrated youth services centre, there are more and more integrated services has been developed in Hong Kong. It is believed that integrated services generated a lot of advantages, such as avoiding wastage of resources and duplication of services. For different target group of people, different kind of integrated services has been developed afterwards. Nowadays, there are integrated youth services (ICYSC), integrated family services (IFSC), integrated elderly services (DECC), integrated disable services (DSC), and integrated mental wellness services (ICCMW) in Hong Kong. In this paper, the integrated services of mental wellness in Hong Kong will be focused and discussed. The strengths and limitations of this integrated social service would be analysed, as well as the improvement of implementation. Background of Integrated Mental Wellness Services In March 2009, Social Welfare Department set up the first Integrated Community Centre for Mental Wellness (ICCMW) in Tin Shui Wai. The major aims of setting up ICCMW are enhancing the social support and re-integrating the ex-mentally ill persons into the community (Social Welfare Department, 2014). The goals of ICCMW are providing one stop services and accessible community supports for the needy. The targeted service users are discharged mental patients, persons with suspected mental health problems, their families or carers of above persons, and people who are interested in understanding and improving their mental health. ICCMW has been established in all the 18 districts in October 2010. Upon now, there are 24 ICCMW provided by 11 non-governmental organization (Social Welfare Department, 2014). Integration of Services Generally, there are three integration levels that integrated services have to address the different needs of clients, includes ICCMW, which are linkage, coordination, and full integration. For the first level, linkage, ICCMW would like to link up the service users and the particular services. For example, it provides information for people who concern about their stress level. For the second level, coordination, ICCMW would serve the function of coordinator between systems and agencies, process to address problem of service users. For example, follow up the case which just has been discharged from hospital by providing day training programs or counseling services in the centre or in other organizations, is a kind of cross-sectional operation between medical and mental wellness sectors. For the third level of integration, full integration, multidisciplinary team cooperation, and community integration would be the targets of ICCMW. There are nurses, occupational therapists, doctors, c linical psychiatrists, social workers as a team to provide mental rehabilitation services for clients, in order to let clients re-integrated to the community. Using the agency of The Wellness Centre in Tin Shui Wai of New Life Psychiatric Rehabilitation Association (New Life) as an example, it provides prevention services and intervention by using recovery-oriented approach. For the prevention, New Life offers a lot of mental health promotions and public education, letting general people have more understanding about mental health and mental illness. For the group work intervention, New Life provides support groups, carer volunteer training, and psycho-education programs for clients. For the individual level intervention, New Life provides counselling, peer support worker training, vocational planning and development services, wellness programs, and so on (New Life Psychiatric Rehabilitation Association, 2013). These kinds of intervention and therapy are for the goal of making people with mental health problem to reintegrate to community. Strengths of ICCMW There are a lot of advantages of setting up integrated services in Hong Kong, so do ICCMW. The first advantage of ICCMW is, convenient to services users. For the service users, ICCMW is multi-functional which provides occupational training, vocational training, care and support, and leisure opportunities. For the public who concern about their mental wellness, they can self approach ICCMW and ask for information and related services. Services are easier accessed nowadays. The second advantage of ICCMW is better coordination among workers and services. After integration, there are multidisciplinary within a team in ICCMW, such as occupational therapist, nurses, doctors, and social workers. They have regular case meetings for discussing how to manage the case, and it is believed that coordination would be better between each division due to more communication. The third advantage of ICCMW is reducing stigmatisation. ICCMW provides different kind of services, not only giving therapy and counselling for people with mental illness but also providing public education and volunteer trainings for mentally ill person or the caregivers. Public education serves the function of letting general public know more about mental health, and letting them to understand that it is not only refer to mental illness but also mental wellness related to everyone. Also, the chance of letting mentally ill person doing voluntary work to community helps them integrating back to community. Therefore, multidimensional services provided by ICCMW would let the concept of mental health and also the mentally ill person integrated into community. Limitations of ICCMW A coin has two sides, although ICCMW provides lot of advantages to service users and community, it is not faces no limitations. Firstly, ICCMW is hard to select centre location. Usually, ICCMW have to select a location for services centre which is close to community for residents convenience, however, there are lots of limitation of setting up centre in estates. Many of the ICCMW reflects that they are hard to find a permanent premises which are large enough for group services and training. And the reason may attribute to the approval time of Welfare Department are too long (Cheung, 2011). In addition, there are objective sounds reject if ICCMW is too close to community or located in estate. For example, in 2010, the residents and the district councilor of Tuen Mun Wu King Estate objected one ICCMW established in their estate, and requested the moving out of ICCMW (MingPao Health, 2011). The major reason is due to stigmatization of mentally ill people who are dangerous and would attack public suddenly. Therefore, residents object if ICCMW too close to the residents. Secondly, there is shortage of man-power. As integrated, ICCMW needs professional staff from different discipline such as nurses, clinical psychiatrists, and doctors. It is all known that, these kinds of professions are now shortage in Hong Kong. Even an ICCMW start in estate, they may face the problem of down man-power for a period of time. Thirdly, it is time-consuming to have meetings for multidiscipline to discuss and examine the case management. Since services integrated, operation complexity would be increased. Regular meeting is essential to understand the roles and views of other professions, however, caseworks and pressures would relatively increase. That makes the workers may easily burnt out for the increased duties. Lastly, there is lack of centralized data for different agencies. Although the communication and interaction between agencies, departments, or bureaus increased under integrated services, they do not have share information between each other. For example, a mental illness patient who just discharged from hospital with marriage problem, Medical Social Services Department in Hospital, Integrated Family Service Center (IFSC), and ICCMW would be involved in this case. Since there are no platforms for information sharing between agencies, the social workers in ICCMW may need to contact IFSC social workers and medical social workers particularly for further information. Procedures may be duplicated due to lack of data transparency. Suggestions for ICCMW First of all, it is suggested that increase the linkage between agencies and organization by developing a platform to share essential information. For example, the doctors in hospital can provide medical reports, integrated progress notes provided by social workers from related agencies etc. It is believed that can raise the transparency of information and data. In addition, it is suggested that Social Welfare Department can simplify the application system of centre location, to avoid the situation that appropriate venue has been rented by other private parties during the long and complicated approval process. Furthermore, it is important to strengthen the public education for public understanding the nature and image of ICCMW. As residents have misunderstanding about people with mental health problem are all dangerous to society, public education is necessary to eliminate their incorrect perception. It is recommended that government should strengthen the advertisement and civil education in community and education institutions, to let people have correct concept about recovered mental ill person that they are also a part of society, and not only harmful to society. Finally, it is also suggested that more resources should be granted for ICCMW. As ICCMW is the newest service within integrated services since 2009, the resources and experiences are not yet well-developed. Therefore, resources like funding for ICCMW allow them to purchase more useful treatment tools for clients, or hire more professional staff for relieving the pressure of existing staff. Conclusion Integration of services in Hong Kong are designed to fulfill different needs of clients, and avoiding wastage of resources. ICCMW generates the advantages of convenience to service users, better cooperation among services workers, and reduce the stigmatization of mentally ill people in society. However, there are still some limitations that ICCMW facing, such as difficulty of selecting centre location, shortage of man-power, time consuming of multidisciplinary meeting, and lack of centralized data. It is believed that ICCMW is still in the developing process, if government provides certain assistances and recourses for them, the integrated services would benefit more and more people in need in the coming future. References Cheung, K. C. (2011), Hong Kong Social Workers General Union. Service Series- Rehabilitation Services, Retrieved on 29 April 2014 from http://www.hkswgu.org.hk/node/70 MingPao Health (2011), â€Å"Only 6 out of 24 ICCMW location confirmed† retrieved on 5 May 2014, from http://www.mingpaohealth.com/cfm/news3.cfm?File=20110213/news/gok1.txt New Life Psychiatric Rehabilitation Association (2013), Annual Report 2012-2013. Retrieved on 2 May 2014, from http://www.nlpra.org.hk/information_n_publications/Annual_report/pdf/049_117_2013.aspx Social Welfare Department (2014), Integrated Community Centre for Mental Wellness (ICCMW), Services Description, retrieved on 2 May 2014, from http://www.swd.gov.hk/en/index/site_pubsvc/page_rehab/sub_listofserv/id_iccmw/ 1

Friday, September 20, 2019

Satire in Tartuffe and Candide

Satire in Tartuffe and Candide The period, known as the Age of Enlightenment or The Enlightenment Period, began in the late seventeenth century. It was a time of great turmoil and intellectual movements that ultimately led to the beginning of the French Revolution. Enlightenment thinkers were the ones who encouraged and proposed that we rely on and trust our instincts for decision making along with the actions that make. Many Enlightenment thinkers, such as Moliere and Voltaire, were famous for their works. They were two writers that used a very particular approach to their works. Tartuffe, by Moliere, and Candide, by Voltaire, both addressed similar topics and themes such as satire for example. Tartuffe and Candide satirized religious hypocrisy emphasizing on free thinking and reason. Jean-Baptiste Moliere, who was originally named Jean-Baptiste Poquelin, was one of the greatest and well-known comic dramatists. He was known as one of the greatest and famous comic writers mainly because his works challenged the imprudence of trusting reason for different life events. One of Molieres most famous works includes Tartuffe primarily for the amount of controversy it sparked related to satire. Tartuffe is a play that tells about a man named Orgon, who is a wealthy family man, who takes a stranger into his home named Tartuffe. He later indeed is discovered to be a religious hypocrite. He doesnt have any morals or indeed values religion. Tartuffe simply used religion as a disguise to manipulate people and do his crimes. He pretends to be extremely religious, but from his actions and behavior, it goes entirely against the morals of religion. For example, when Tartuffe sees Dorine in Act 3, Scene 2, he tells her: Cover your bust. The flesh is weak Souls are forever damaged by such sights, When sinful thoughts begin their evil flights. From this scene, there is clear evidence showing how Tartuffe is a hypocrite. Here, he preaches about the importance of chastity; however, in the scene that follows, he goes against this statement when he tries to pursue Elmire. Tartuffe tries to persuade Elmire to cheat on Orgon, but she comes up with a plan to expose Tartuffes true personality to Orgon as well as to show him how Tartuffe was trying to seduce her. As a result of this scheme, Orgon sees first-hand that Tartuffe is a religious hypocrite. The way that Moliere displays Tartuffes behavior, when comparing the two scenes, allows the audience to conclude that the way Tartuffe acts doesnt at all coincide with his words. The two different behaviors exemplified in the two scenes is meant to satirize the religious hypocrisy integrated into Tartuffe. A central theme of Tartuffe is religious moderation displayed through Cleante. He shows real pious virtue throughout the play by expressed ideas and thoughts opposed to religious hypocrisy embodied in Tartuffe. Religious moderation is communicated by Cleantes voice through his speeches: So nothing is more odious to me Than the display of specious piety Which I see in every charlatan Who tries to pass for a true holy man    Religious passion worn as a faà §ade Abuses whats sacred and mocks God. They dont exhibit zeal thats more intense Than heaven shows us in its own defense. Theyd never claim a knowledge thats divine And yet they live in virtues own design. They concentrate their hatred on the sin, And when the sinner grieves, invite him in. (Molià ¨re 24-25) This speech by Cleante in Act 1 Scene 5 is supported by a firmly structured argument to emphasize on Molià ¨res belief and support of religious moderation. Molià ¨re uses Cleantes speech to compare between the people that are actual pious against those individuals who are only pretending to be pious, like Tartuffe. Those who pretend to be pious do more talking and preaching versus actually showing actions to back up their words. The extremely holy people follow God as well as use actions more opposed to teaching. I think by Moliere using these statements in his play through Cleante; he is sending a message to his audience to exhibit religious moderation by being like Cleante. Francois-Marie Arouet, better known by his pen name Voltaire, was an outspoken and fearless writer. So much so, he landed himself in exile more than once. He was determined to have his work published by any means even if he had to do it secretly. One of Voltaires most notable works was Candide, which was written in response to news that Voltaire found to be disturbing. Unlike Tartuffe, where religious hypocrisy is embodied by one character, Voltaire attacks religious hypocrisy through religious communities. Like Moliere, Voltaire satirizes religious moderation as well. In Candide, Voltaire uses the character, Pangloss, as a way to mock his view on religious moderation. Voltaire believed humans should rely on their reason and senses to make decisions and understand the world. Throughout the novel, Pangloss has an optimistic view of how he sees the world. He believes that God made the best possible world that we can live in and that everything that happens is necessary. Candide recalls his mentors philosophy: It is clear, said he, that things cannot be otherwise than they are, for since everything is made to serve an end, everything necessarily serves the best end. (Voltaire, 101) Panglosss philosophy encourages and promotes that people should trust and follow their religious faith blindly. Voltaire satirizes this because he has a different belief. As demonstrated by Candides misfortunes throughout the novel, his mentors optimistic view and philosophy proved to be inaccurate, such as with the drowning of Jacques the Anabaptist. After this disaster and all the other horrible experiences, leads Candide to question Panglosss philosophy about whether or not his unfortunate experiences are part of the best of all possible worlds. Moliere and Voltaire successfully satirize their views on religious hypocrisy and moderation in Tartuffe and Candide. With each of their works, they hoped to get a message out to society that would catch attention as both did with the amount of controversy their works caused. Even though their works were written many centuries ago, it served as a foundation for satirical writers in the modern day. The world we live in today is still filled with negative aspects of religion such as with the Charlie Hebdo shooting in 2015. The messages Moliere and Voltaire communicated are still important to this day and probably needs to be addressed more elaborately in the present age than it was at the time their works were published. Works Cited Page Moliere. Tartuffe. The Norton Anthology World Literature, vol. 2, 3rd edition, pp. 12-68. Voltaire. Candide. The Norton Anthology World Literature, vol. 2, 3rd edition, pp. 97-159.

Thursday, September 19, 2019

European History - Unification of Italy :: European Europe History

Unification of Italy Q: Describe & Explain the Unification of Italy. The Unification of Italy divides in to 3 main stages: 1815-1830: Revolts all over Italy. Revolts are suppressed. 1848-1849: Revolts all over Italy. Revolts are suppressed. 1858-1870: The unification of Italy Introduction To understand the unification of Italy, matters before the revolution need to be examined. Up until 1716, Italy was just a big piece of land divided among small kingdoms of monarchs. (ref. H.O. #1 p.29) When napoleon Bonaparte conquered Italy, he left them 3 things, which were probably the key characteristics in the revolution: - Efficient Government. - A practical demonstrations of the benefits from a unified Italy - Hatred towards foreign influence. After the fall of Napoleon, the major European powers (Austria, Russia, Spain, United Kingdom, & Prussia) what was to be done with Italy, which was conquered at the time by Napoleon. It was thus decided that Italy would be divided among different monarchs, all associated with the Habsburgs (except for Piedmont Sardinia, which was to be ruled by Victor Emmanuel, an independent monarch, and Papal States, ruled by the pope.). (ref. H.O. #1 p. 29-30) Austria had very strong domination over Italy. It had agreements with Ferdinand, king of Kingdom of the 2 Sicilies, and helped the pope maintain his kingdom. Only Piedmont Sardinia wasn't influenced by Austria (ref. H.O. #1 p. 30). 1815 - 1830 Revolution Almost all "'Italians" hated the foreign influence of Austria on Italy. Metternich, an Austrian prince wanted to make sure no nationalist activities were in process in Austria's territories in Italy (which was Lombardy Venetia). He imposed repressive rule in Lombardy Venetia. German was the official language, a strong Austrian army was always present to suppress any hostile activities, an efficient system of spies reported on any nationalist activities, a strict censorship of news was present, and Italian history was banned in schools to avoid the younger generation from learning about the glorious Roman past. Metternich caused even further resentment when he obligated Lombards to serve in Austrian army, obey Austrian rules, and pay high taxes to Austrian empire. Lombardy Venetia's situation was very bad, and nothing seemed able to be done. (ref. H.O. #1 p. 30). The situation in Lombardy (and in other parts of Italy) led to the establishment of many secret societies dedicated to the cause of Liberalism and Nationalism the biggest and most famous of those societies was named Carbonari.

Wednesday, September 18, 2019

Philosophy and Contemporary Science :: Philosophical Essays

Philosophy and Contemporary Science ABSTRACT: This paper is concerned with some of the differences between philosophy and contemporary science, and with the significance of these differences for the question of the nature of philosophy. Differences of particular interest here are ones that tend to be concealed and ignored through the influence of the professionalist attitudes of contemporary science, an influence that manifests itself in the prevailing normative attitude to the vocabularies and linguistic practices of professional philosophy. It is argued that this normative attitude is questionable in the light of a feature that we take to be essential to philosophy: always being open to the question of its own nature and task. A traditional, and still common, view of the difference between philosophy and the 'special' sciences is based upon the dichotomies universal/particular or general/special. It is said that philosophy deals with the general issues concerning some subject matter while the special sciences take care of the more specific issues. Chemistry concerns itself with properties of various chemical compounds and physics with forces and the motion of bodies, while philosophy deals with the general nature of matter, general questions of causality, determinism, etc. Linguistics deals with special, empirical questions about the nature of language, while philosophy is supposed to discover the general principles that govern all language. The ontological question about 'what there is' in the world, is, in Quine's words, "a shared concern of philosophy and most other non-fiction genres." (1) It is the use of more general or broader categories, such as, for instance, physical objects or classes, that distinguishes the ontological philosopher's interest in what there is from the scientist's. This 'synoptic view' of philosophy, as Moritz Schlick called it, usually also involves the view of philosophy as a science. (2) As physics studies the specific structure of matter, so philosophy studies its general nature. Quine says, for instance, that "Philosophy ... as an effort to get clearer on things, is not to be distinguished in essential points of purpose and method from good or bad science." (3) Like the special sciences, philosophy is also a science, only one of a more general character. But Quine's philosophy represents only one, naturalistic, version of this synoptic view of the nature of philosophy. There are others, both within and outside the analytic tradition. And there is a great deal to be said about the difference between these philosophies, for instance, that the ones in the Kantian tradition are more oriented towards discovering the general conditions of human knowledge and experience, and have less to say about the general nature of reality.

Tuesday, September 17, 2019

Death Penalty: Pros and Cons Essay

Capital punishment has been the center of much controversy dating back to its origins. Although the roots of capital punishment can be traced as far back as 1697 BC, arguments over its effectiveness and morality continue in the midst of its existence today. There are many people who have come up with arguments for both sides. Most people who believe that the death penalty is a fair punishment use the argument, â€Å"lex talionis†, meaning, â€Å"an eye for an eye, a tooth for a tooth, an arm for an arm, a life for a life.† (Hooker). While most people who are in opposition use the argument that capital punishment is a cruel and unusual punishment which violates the eighth amendment to the United States Constitution. Today, in the United States, there are approximately 3,624 people on death row. (Pro-death Penalty.com) Throughout history there have been many methods of executing criminals. Some of these methods are crucifixion, stoning, drowning, burning at the stake, impaling and beheading. But more modern methods of capital punishment are typically accomplished by lethal gas or injection, electrocution, hanging or shooting. The argument over the brutality of capital punishment is at the head of topics concerning it as a whole. These arguments are also not only centered in The United States but all over the world as well. About 90 nations have denounced capital punishment by abolishing it, but almost an equal amount of nations retain it (MSN Encarta). Capital punishment remains legal in all but twelve states. Alaska, Hawaii, Iowa, Maine Massachusetts, Michigan, Minnesota, North Dakota, Rhode Island, Vermont, West Virginia and Wisconsin all do not use the death penalty. (Pro-death Penalty.com) Many people feel that the death penalty is cruel as well as an ineffective crime deterrent. But the most successful argument that is used against the death penalty is that it infringes the eighth amendment to the United States Constitution. Another argument against capital punishment is that people who are innocent may be killed. Life without parole is one. A lengthy sentence with treatment, with release conditional upon proof of rehabilitation, is another† (Williams). The people who are opposed to taking the life of a convicted murderer do not believe that premeditated, state-sanctioned killing is justifiable under any circumstances. They also refute the idea that the death penalty deters crime. Some states say that a person will stop  themselves from killing or committing a crime if, in the back of their minds, they know that the punishment for their actions could be the death penalty. Statistics have shown that the states that use the death penalty have a higher crime rate than those with out it. The chance that a person who has been convicted of the death penalty is innocent is also a factor. This causes much controversy because innocent lives are taken and it could have been prevented. Lastly, opponents of the death penalty say that when the states execute killers in an attempt to proclaim that murder is wrong, they undermine their own, moral authority. On the other side of the argument, people claim that capital punishment is a deterrent for future criminals, a proportionate punishment for those who have killed, and it is also said to be less harsh than life imprisonment because it is quick and instantaneous. Ernest Van den Haag contended that human beings are morally responsible for their actions and should therefore be punished accordingly for their crimes (Williams). The definition for justice is â€Å"fair treatment† (Stewart). In the case of premeditated murder, capital punishment is the only just punishment. Nothing less of the death penalty would be proportionate to murder. Immanuel Kant argues that â€Å"even guilty-ridden killers should die in order to gain release from their anguish.† (Williams) The fact that a convicted murderer has the chance to live while their victim is dead is unfair. Why is that they are able to take an innocent life and then live to tell about it? Execution is even more humane than sentencing someone to life in prison. Making the prisoner suffer by rotting in jail for the rest of their life is more torturous and inhumane than execution. The people who favor execution also claim that it is the most effective means of crime deterrence. Most people think about the consequences to their actions before they actually follow through with what they are thinking. Capital punishment not only punishes those who commit the crimes, but also prevents future crimes by scaring the would-be murderer with the consequence he would pay for his action. In the end, the main support for capital punishment comes from one Greek phrase, â€Å"lex talionis,† meaning, â€Å"an eye for an eye, a tooth for a tooth, an arm for an arm, a life for a life.† When it comes to capital punishment, most people find themselves wondering if it is a fair and effective punishment. Arguments for both sides are very strong. Those who oppose the death penalty fight against it because they think it is unfair and unjust. They also believe that no one should have their lives taken away as a punishment. They also believe that the argument that capital punishment is an effective deterrent to crime is invalid. Because only fractions of people on death row are actually executed, most criminals would take the chance. They also believe that life imprisonment is as much of a deterrent as the death penalty. People on the other end of the argument believe in criminals receiving equal punishment for the crime that they commit. The only punishment in proportion to murder is execution. The United States government has many regulations regarding the death penalty. All of those rules oppose using the death penalty in an unfair manner, but do not prohibit the death penalty completely so we should try to use the death penalty for those who deserve it. Works Cited MSN Encarta Encyclopedia. (2003). Capital punishment. March 3, 2003: http://www.encarta.msn.com/encnet/refpages/refarticle.aspx?refid=761570630 Stewart, G. (1998). The death penalty. San Diego: Greenhaven Press Inc. Williams, M. (2000). Capital punishment. San Diego: Greenhaven Press Inc. Williams, M. (2002). The death penalty. San Diego: Greenhaven Press Inc. www.pro-death Penalty.com (2003).

Monday, September 16, 2019

Adolescent Development in Juvenile Recidivism

Punishment is a word that has many different meanings. It differs from person to person, state to state and even country to country. When looking at the criminal justice system the purpose of punishment is deterrence, rehabilitation, retribution, and incapacitation (Bontrager, Smith, & Winokur, 2008). Punishment involving adults is hard but when dealing with adolescents it is even more difficult. Adolescence is often thought to be a time of irrational and emotion influenced behavior. There are many who think that adolescence is just a phase that is an entity in and of its self.While many people can see the correlation between the actions and behaviors that happen in adolescence to the habits and life style in adulthood few people see the correlation between a person’s early childhood and the affect that has on his or her adolescence. There is no developmental phase that stands totally alone. Each phase has a lasting consequence ramifications on the next. This progressive devel opmental phase has lasting ramifications on the adolescent’s behavior, self-concept and maturity. Because of this there is a need to view juvenile crime and punishment differently than adult crime and punishment.The reason for this is because some research has shown that recidivism rates among juvenile parolees are very high. It can range anywhere from fifty five percent to seventy five percent (Krisberg, Austin, and Steele, 1991). There is evidence that a vast majority of juvenile offenders who have been confined do not stop committing crimes when they are released. In fact, many juvenile offenders continue their criminal involvement into adulthood (Hamparian et al. , 1984). There is a need to halt juvenile crime before it begins and there needs to be a way to halt the progression of juvenile crime being indicative of adult crime.The purpose of this paper is to demonstrate how childhood development affects adolescent’s development and how this development is directly related to a troubled adolescent’s recidivism rate in relation to family, community and social support. When sentencing juvenile offenders there needs to be an emphasis not only on punishment but rehabilitation. Crime prevention, whether on the juvenile level or adult level, falls into the three categories, of primary, secondary and tertiary prevention. Primary prevention focuses on the conditions that may foster criminal activity. Primary prevention works to sway juveniles who are immersed in ommunities and cultures that promote violence and crime to seek healthier ways to live ((Bendit, Nieborg, & Erier, 2000). For example,i. e. a juvenile living in a depressed area will see that drugs and theft are the primary means of survival. Taking that juvenile to a farm, or a camp, exposes them hard, honest work is more satisfying, and less stressful than devious means of support. The idea behind primary prevention is the desire to create a more positive perspective, specifically for juveniles, which will effect positive change which will, hopefully, keep the adolescent from criminal behavior.Primary prevention speaks to pretty much all aspects of life. It takes into account poverty, unemployment and a wide variety of other social and psychological burdens. It enfolds all of the aforementioned items with support for families, schools, urban development, healthcare, stabilizing and strengthening individual personalities, social education and combating prejudice (Bendit, Nieborg, & Erier, 2000). Primary prevention is an attempt at a catchall. The concept behind secondary prevention is not to look at the general environment, as in primary prevention, but to focus on a small, clearly defined group.This group encompasses children and young people whose individual development, or circumstances, or both, cause them to be a more likely candidate for becoming a potential offender. Secondary prevention focuses on helping people who fall into this group specifically. The help may involve either working with adolescents, who live in socially depressed areas. It can also mean street work, getting involved on the youth’s direct level, for young people who are difficult to reach in other ways (Bendit, Nieborg, & Erier, 2000). When looking at crime prevention Ttertiary prevention is the most clearly defined of the three categories.It is very specific in relation to its aims and target groups. Tertiary prevention endeavors to stop repeated offences and encourages the social integration of young offenders. In fact, the younger the age of an offender, the greater the significance of getting the offender’s support system involved (Bendit, Nieborg, & Erier, 2000). This leads us into the path of criminal behavior in adolescents. Vygotsky’s Theory of cognitive learning is a socio-cultural theory of cognitive development that is based on the idea that learning happens primarily through a child’s interaction with the world.This theory shows the learning progression from infancy to early childhood to adolescence to adulthood. Adults are the key to this theory and to the concept of child to adolescent development. Adults shape and foster a child’s learning and development, intentionally, in a methodical manner depending on which culture and society the child hails from (Ormrod, 2008). Culture is often viewed as a local though it is not limited to a specific location. A person’s culture is not just where a person was born, lived and died. Culture includes the how of one’s birth, life and death.There needs to be awareness that intentionality can be done on purpose, with a goal and purpose set forth, but it can also be done with the mindset of failure. When a parent, teacher, or a significant person in a child’s life does not actively participate in the child’s development that loss of interaction may set the child up for failure. It is intentionality focused on failure. Making a cho ice to do nothing is actually making a choice to do something. It’s a choice of promoting apathy, indifference and a lack of concern.It is a choice that may cause irrevocable damage and harm that has lasting implications. An example would be not making a decision concerning salvation through Jesus Christ. When a person does not choose Christ he or she is choosing Satan. While many people may think that concept is harsh it is true. When parents, loved ones, teachers, pastors or anyone who plays a significant role in a child’s life chooses not to be actively involved it will cause reverberations that the child will feel forever. Thus, when a juvenile commits a crime and no one intervenes it creates chaos and confusion.It is generally acknowledged that dysfunctional parenting practices and family conflict are common hazards related to a wide variety of behavioral and emotional problems in children and adolescents. Improving parenting skills and enhancing the confidence ad olescents hold in their parents has the greatest potential in improving the children’s health, status, well being, and in reducing the risk of developing serious mental health problems or behavioral problems. There is extensive data to support the importance of good parenting in the maintenance, treatment and revention of childhood difficulties. This evidence comes from a wide variety of sources including different disciplines, behavioral genetics, developmental studies, and intervention research. There is substantial evidence that behavioral family interventions, based on social learning principles, are effective in the prevention and treatment of a range of childhood behavioral and emotional problems (Sanders, 2003). This data will have a huge impact on whether an adolescent commits a crime and also the recidivism rate when the child is released from whatever punishment given.The major premise of Vygotsky's theoretical framework is that social interaction plays a primary ro le in the development of cognition (Kearsley, 2010). Vygotsky taught that children learn how their culture interprets and responds to the world through formal and informal methods (Ormrod, 2008). This knowledge draws a parallel between understanding what others consider acceptable, in and for society, and turning that knowledge inward and deciding what is acceptable for ones’ self.This knowledge happens as a child moves from early childhood to middle childhood . As the child enters adolescence it begins to show up in social and emotional competences. Although middle childhood is an important developmental period for the assimilation of various skills to meet the complexity of coming social situations, the foundation for them has its origin in infancy. In infancy and early childhood, a child’s parental support allows him or her to learn to regulate behavior with consistent responsiveness from the parent to guide this developmental course.Increasingly, the child begins t o assume more control and can by early elementary school become more self-directed in carrying out the intricate set of skills required for problem solving in social situations. Accordingly, to obtain a child’s competency in social problem solving, measurement systems need to place demands on the child’s self regulatory, executive processing, and social engagement. Other basic skills that are also involved in social problem solving are competent language, regulation of attention, and memory (Landry, Smith, ; Swank, 2006).When a child does not learn these skills there is a fundamental lack in his or her foundation. The foundation may continue to be built upon but at some point it is likely to falter. Social and emotional competences have a wide range of developmental indicators that adolescents need for successful social adaptation. These indicators embrace positive interactions between adolescents and parents, teachers, care-givers and peers, emotional knowledge, emoti on regulatory abilities and relationship skills.When the adolescent is made aware that there is a problem in his or development scheme successful competency indicates a willingness to participate in special education programs for behavior problems. When a child moves into adolescence and these developmental indicators are not present, or are skewed, it is going to cause more developmental issues to arise. The process of maturation becomes much more difficult as the foundation needs to be reset in order to rebuild upon. The developmental indicators begin to show what the adolescent has retained in teaching form childhood to adolescent.A key component to seeing the correlation between a well adjusted adolescent and a maladjusted adolescent is to watch the behavior. Such behaviors would be acting-out, assertive social skills, emotional or behavioral disorder, frustration tolerance, peer social skills, shyness, anxiety and task orientation. Watching, and repairing deficiencies, earlier in childhood affects social and emotional development in early adolescence (Niles, Reynolds ; Roe-Sepowitx, 2008). To more fully understand social competencies in daily situations there needs to be an observance of the integration of skills.There needs to be a link between competencies during middle childhood to the more complex social challenges in adolescence. As children enter middle school they are expected to interact in social situations without a huge amount of structure and support from outside sources (Landry, Smith ; Swank, 2009). The reason for this is because this skill set should have been taught to the adolescent during the period of lower mental function (Ormrod, 2008). The social interactions become more complex because the adolescents are expected to consider each others’ points of view.They are then also expected to assimilate other people’s views with their own and give feedback based on the knowledge they possess. Based on what was said earlier, ado lescents can show success with these demands if they are demonstrating the ability to perceive and respond to the goals of others as well as others’ perceptions and beliefs. They can also show failure by being close minded or self-absorbed. Failure here may lead to an adolescent being ostracized, ignored or made fun of (Steinberg, 2005).Proficiency in shared interactions with others necessitates an assortment of cognitive, social, and verbal skills. From the social realm, adolescents need to understand the behavior of others. This is not limited to just understanding other people’s behaviors but also understanding that they, themselves, may have different perspectives, intentions, and knowledge. In order for this to occur successfully, they need to identify social cues and modify their strategies on the basis of the feedback received from a social peer.Cognitively, a child is required to keep focused and attentive and use information to plan and reason how to organize behaviors to achieve problem solving with others (Landry, Smith ; Swank, 2009). This is executive functioning which enters the realm of higher mental function (Ormrod, 2008). When a person goes from child to adolescent there needs to be an understanding of other people’s behavior. It is critical in being able to function in society. When this area is not developed fully it may cause issues in the area of self-concept, maturity and behavior (Steinberg, 2005).Integration of the many skills needed to function in more complex social situations is social problem solving. The ability to plan, sequence behaviors, and alter problem-solving strategies on the basis of feedback is often referred to as involving executive processing. Many theorists believe this is a critical set of behaviors for social competence because they help the child organize the information from the environment and process it to effectively comprehend social experiences.There is also an emphasis on the fact that social problem-solving requires specific behaviors. Examples would be goal directedness and planning. These behaviors fall under the heading of self-regulation. For adolescents to function competently they require the ability to create new strategies for use in unique situations and they must be able to self-examine in order to restrain behaviors that are not appropriate for the social situation. Integration of these skills is occurring across childhood (Astington ; Pelletier, 2005). In sSaying hat though, there is a prolonged progressive course where these abilities multiply in complexity as the child enters into adolescence. These behaviors are multidimensional, and can fluctuate fluidly depending on the social context (Steinberg, Dahl, Keating, Kupfer, Masten, ; Pine 2006). Social context is very important when looking at juvenile crime and recidivism rates. A common response that spans history, in the public’s concern with juvenile delinquency and violence has been to pas s legislation promising stiffer penalties as well as harsher sentences for juvenile offenders.What needs to be seen, though is the fact that crime damages people, communities, and relationships. There needs to be a balance created that includes the needs of the victim, offender, and communities. For there to be a healthy restoration process each party needs to be involved. While an offender needs to be punished unless there are support systems in place for the offender, when released, the recidivism rates for that particular offender will continue to rise (Stenhjem, 2003).

Sunday, September 15, 2019

Revisiting Day of the Week Effect in Indian Stock Market

In recent years the testing of market anomalies in stock returns has become an active field of research in empirical finance and has been receiving attention not only from academic journals but also from the financial press as well. Among the more well-known anomalies are the size effect, the January effect and the day-of-the week effect. According to this phenomenon, the average daily return of the market is not the same for all days of the week, as we would expect on the basis of the efficient market theory. The objective of this paper is to examine the existence of day of week effect in Indian stock market.Daily closing prices of S&P CNX Nifty index have been analyzed over fifteen years period commencing from January 1994 to December 2008. A set of parametric and non parametric tests has been used to test the equality of mean returns and standard deviations of the returns. The mean returns on Monday and Tuesday are negative while on Wednesday these are highly positive. Also, the i mpact of introduction of rolling settlement on the stock returns is observed. The results show that before rolling settlement came in 2001, Tuesday was showing highly negative returns and Wednesday highly positive.But after the introduction of rolling settlement, the seasonality in the distribution of the mean returns across different days of the week ceased to appear. Thus the markets have become more efficient over a period of time. KEY WORDS: Market Efficiency, Calendar Anomalies and Day-of-the-Week Effect INTRODUCTION A Stock Exchange is a common platform where buyers and sellers come together to transact in securities. It may be a physical entity where brokers trade on a physical trading floor via an â€Å"open outcry† system or a virtual environment.The Stock Exchange, Mumbai (BSE) and the National Stock Exchange (NSE) are the India's two leading stock exchanges. Indian security market is one of the oldest markets in Asia. It has come a long way from earlier days of flo or trading to the present day screen and net based trading. This study is an attempt to have a deeper insight in to the behaviour and patterns of stock price distribution in the Indian stock market. The price of a security should vibrate around its intrinsic worth in any efficient market.In finance, the efficient-market hypothesis (EMH) asserts that financial markets are â€Å"informationally efficient†, or that prices on traded assets, e. g. , stocks, bonds, or property, already reflect all known information. The efficient-market hypothesis states that it is impossible to consistently outperform the market by using any information that the market already knows, except through luck. Therefore, the past price movements can in no way help in speculating the prices in future. The price of each day is independent. It may be unchanged, higher or lower from he previous price, but depends upon new pieces of information being received each day. So seasonalities cannot be used to form ulate trading strategies to earn abnormal returns according to efficient market hypothesis theory. Calendar anomalies are cyclical anomalies in returns, where the cycle is based on the calendar. It describes the tendency of stocks to perform differently at different times. For example, a number of researchers have documented that historically, returns tend to be higher in January compared to other months (especially February).There are three types of efficiencies as explained in efficient market hypothesis. So calendar anomalies mainly explain weak form of efficiency which says that previous price changes or changes in return are useless in predicting future price or return changes. Some of the calendar anomalies are Month-of-the year effect, Month-of-the quarter effect, Week-of-the month effect, Day-of-the-week effect or Weekend effect, Monday effect, Hour-of-the-day effect or the End of the-day effect, holiday effect and turn of the month effect etc. Among them the day-of-the-week effect is most widely documented across the countries and markets.In context to stock market the majority of research findings, indicates that the stock returns remain low or negative on Monday. This paper examines the day-of-the-week effect in Indian stock market, using S;P CNX Nifty data of last fifteen years from January 1994 to December 2008. REVIEW OF LITERATURE There is an extensive literature on the day-of-the-week effect in the stock returns. This section examines a few research works on the day of the week effect in Indian and international stock markets. Ziemba (1993) investigated the weekend hypothesis for the Japanese market using daily data from 1949 to 1988.Tuesday recorded negative returns following a one day weekend and Mondays declined after two days weekends. Balaban (1994) found day of the week effect in an emerging stock market ISECI of a developing country Turkey for the period 1988 to 1994. Highest returns on Friday and lowest returns on Tuesday were observed. Mishra (1999) studied day of the week effect in Indian stock market using Sensex and Natex for the period 1986 to 1998 indicating the presence of day of the week effect in Indian stock market. Friday returns were found highest and significantly different from the mean returns of other days. Hence there exists a Friday effect.Berument and Halil Kiymaz (2001) tested the presence of the day of the week effect on stock market volatility by using the S;P 500 market index during the period of January 1973 and October 1997. The findings showed that the day of the week effect is present in both volatility and return equations. While the highest and lowest returns were observed on Wednesday and Monday, the highest and the lowest volatility were observed on Friday and Wednesday, respectively. Further investigation of sub-periods reinforced findings that the volatility pattern across the days of the week was statistically different.Sarma (2004) examined seasonality across the days of week in Indian stock market using BSE indices- SENSEX, NATEX and BSE 200. Highest variance on Monday was found and weekend effect was confirmed by this study. Nath and Dalvi (2004) examined the day of the week anomaly in Indian stock market for the period from 1999 to 2003 using index S;P CNX NIFTY data. The study found that before introduction of rolling settlement in January 2002, Monday and Friday were significant days. However after the introduction of the rolling settlement, Friday became significant. Mondays were found to have higher standard deviations followed by Fridays.Davidsson (2006) found evidence of day of week effect in S;P 500 index. Davidsson found Wednesday was the weekday with highest rate of return and Monday was weekday with lowest rate of return. Also Monday was the only day with negative rate of return. Wednesday’s returns were found approximately four times of Monday’s returns. Badhani (2008) examined the presence of day-of-the-week effect on stock retu rns, trading volume and price volatility at the NSE during the period of 10 years from 1995-2005. Wednesday effect was found during earlier weekly settlement regime which now disappeared.Monday and Tuesday returns were consistently low but during recent sub period these were not significantly different from other days of week. Also on Monday the average trading volume was significantly low and price volatility was high consistently across the entire sample period. Mangala (2008) examined day-of-the-week effect in sub periods in Indian stock market using S;P CNX Nifty data. Highest returns on Wednesday and lowest on Tuesday were observed. Also findings showed that seasonality in return distribution across weekdays was confined to pre rolling settlement time period; thereafter seasonality vanished.DATA AND METHODOLOGY This study covers a sample period of fifteen years from January 1, 1994 to December 31, 2008 comprising a total of 3695 observations(days). The stock prices are represen ted by S;P CNX Nifty index. The closing values of this index have been obtained from the official website of National Stock Exchange (www. nseindia. com). There was trading on certain weekly closing days (i. e. 18 Saturdays and 3 Sundays); these days have been excluded from the sample. During the above sample period of fifteen years many structural changes also took place in the market.For example rolling settlement was introduced in place of weekly settlement system. Therefore, the behaviour of stock prices has been studied on an yearly basis so as to gauge the impact of these changes on the stock prices. Measuring the Daily Returns Daily percent return on the index for a given day of the week has been calculated by subtracting the closing price of the previous trading day from closing price of that day, then dividing the resulting no. by closing price as on the previous trading day and multiplying by 100. Rt = Pt-Pt-1 * 100 Pt-1 Rt is daily return on the share price index for day tPt is the closing value of index for the day‘t’ and Pt-1 is the closing value of the index for the preceding day. Hypothesis and Testing Procedure The null hypothesis is that there are no differences in the mean daily returns across the weekdays. The non parametric Kruskall- Wallis (H) test has been applied to test seasonality in returns across weekdays to test the hypothesis. Null hypothesis is: – Ho:  µ1=  µ2=  µ3=  µ4=  µ5 Here,  µ1,  µ2†¦Ã‚ µ5 represent mean returns of different trading days of week. It means that mean returns across all the five days of week are equal. Alternative hypothesis is: – H1:  µ1?  µ2?  µ3?  µ4?  µ5It implies that there is significant difference in mean returns across the trading days in a week. Different statistical tools have been used to find the results like mean, standard deviation, range, skewness ; kurtosis etc. Then the most scientific and logical non-parametric Kruskall-Wallis (H) test h as been applied to check the hypothesis. The Kruskall Wallis test requires the entire set of observations being ranked – higher the value, higher is the rank and vice-versa- then arranged into nj ? 5 matrix where nj represents the rank of the return and columns represent the day of the week (Monday through Friday).The value of H is calculated by formula: |H |= |12 |( |[pic] |(Rj)2 |) |  Ã¢â‚¬â€Ã‚   |3(N+1) | | | |[pic] | | |[pic] | | | | | | |N(N+1) | | |nj | | | | | | | | | | | | | | Where: Rj= sum of ranks in the jth column nj = number of cases in the jth column N = sum of observations in all the columns The calculated H value has been compared with the table value of the chi-square(? 2) distribution with (k-1) degree of freedom, where k stands for the number of trading days in a week.Hence H0 is rejected if H;gt; ? 2 H0 is accepted if H;lt; ? 2 The value of H in our study is taken as the critical value at 1% as well as 5% level of significance. Further Dunn’s mul tiple pair comparison test based on rank matrix built in K-W test has been used to find seasonality by a pair wise multiple comparison procedure. It identifies whether particular day of the week differs from other days of the week. The test procedure relies on Kruskall-Wallis rank sum Rj. The data in the rank-day matrix prepared for ‘H’ test is used for this purpose. For a given level of ? decide ?  µ ? ? if |Ru-Rv| ? Z [? /k(k-1)] [N(N+1)/12]1/2 [1/n µ + 1/nv]1/2 Where,  µ = 1, 2†¦Ã¢â‚¬ ¦k-1 v= +1,†¦Ã¢â‚¬ ¦. k k = 5 N = total number of observations n µ = corresponding number of observations in the uth column nv = corresponding number of observations in the vth column Ru = Average K-W rank sums in the uth columns of the rank matrix Rv = Average K-W rank sums in vth columns of the rank matrix Z[? /k(k-1)] = the upper percentage point of the unit normal distribution for a given significance level for 99 percent confidence level is 2. 575 Further the retu rns have been analyzed for two sub-periods i. e.Sub period-1 before rolling settlement (weekly settlement period) ; sub period-2 after the rolling settlement was introduced. In weekly settlement time period, Tuesday used to be as the settlement day on NSE. In 2001, rolling settlement was introduced which shifted settlement cycle from a fixed day of the week to fixed settlement lag. Tuesday settlement might be the possible reason for the observed seasonality in stock returns. DATA ANALYSIS Here the day of the week pattern of the S;P CNX Nifty data from January 1994 to December 2008 has been tested, results of which have been depicted in Table 1.It is observed from the table that the mean returns on Monday i. e. -0. 08563 percent are minimum followed by Tuesday. Mean returns on Wednesday, Thursday and Friday are positive out of which Wednesday’s return with 0. 303 percent is maximum across all the days of the week. The mean return on Wednesday is about 8 times the overall mean return. The variation in mean returns measured in terms of standard deviation is found maximum on Monday (1. 870303 percent) followed by Friday (1. 740897 percent). It shows that trading on week start and week end is more volatile than other days of week.Skewness is positive only on Wednesday while other days of week have negatively skewed distributions. Kurtosis tells us the extent to which a distribution is peaked or flat topped when compared with a normal curve. The return distribution on Monday, Tuesday and Friday is leptokurtic while on Wednesday and Thursday are platykurtic. Through table it is also observed that range on Monday is highest which is also a measure of Dispersion. There is a significant difference in mean returns across different the different days of the week as evident by K-W (H) statistics (21. 78) which is highly significant at 1 percent level of significance. Therefore the null hypothesis of equality of mean returns across various days of the week stands rej ected. |Table 1. Summary Statistics of Daily Stock Returns of S;P CNX Nifty(Jan 1994-Dec. 2008) | |   |Monday |Tuesday |Wednesday |Thursday |Friday |All Days | |Mean |-0. 08563 |-0. 07615 |0. 30300 |0. 1895 |0. 03221 |0. 03838 | |Standard Deviation |1. 87030 |1. 50858 |1. 62655 |1. 55153 |1. 74090 |1. 66944 | |Skewness |-0. 71612 |-0. 15909 |0. 40400 |-0. 05609 |-0. 35999 |-0. 24662 | |Kurtosis |4. 29741 |4. 47636 |1. 79652 |1. 53957 |5. 66062 |3. 98682 | |Range |7. 54838 |8. 29523 |7. 9590 |6. 30507 |7. 83089 |20. 53297 | |No. of Observations |741 |742 |740 |744 |728 |3695 | |K – W(H) Statistics 21. 278* | * Significant at 1 percent level for 5-1 degrees of freedom Table 2 represents actual and expected multiple comparison values as per Dunn’s multiple pair comparison test to study pair wise comparison among different days of the week. This test is based on rank matrix built in Kruskall Wallis Test.The calculation of actual and expected values is shown in table 3 wh ile the deviation of actual from expected ranks is shown in table 3. So it is observed from the table 3 that there is inequality in Monday – Wednesday, Tuesday – Wednesday, Wednesday – Thursday and Wednesday – Friday pairs as these are showing positive deviation of absolute rank sum values from the corresponding Z value or expected value. It means these pairs are showing more inequality in returns than expected and Tuesday – Wednesday is showing highest positive deviation. Also it is observed from the table that Wednesday appears in all above pairs.It means Wednesday returns are significantly different from the other days of week. Wednesday is showing highly different mean returns from rest of the days. So a trading strategy of buying on Tuesday and selling on Wednesday may help an investor to earn abnormal returns. |Table 2. Actual and Expected Multiple Comparison Values | | | |   |Actual |Expected | |   ||RU ?Rv| |Z |[N(N+1)/12]1/2 |(1/nu+1/n v)1/2 |Z[N(N+1)/12]1/2 (1/nu+1/nv)1/2 | |Monday-Tuesday |40. 64 |2. 575 |1066. 799 |0. 0519 |142. 6521 | |Monday-Wednesday |197. 07 |2. 575 |1066. 799 |0. 0520 |142. 7620 | |Monday-Thursday |30. 38 |2. 575 |1066. 799 |0. 0519 |142. 5697 | |Monday-Friday |50. 24 |2. 75 |1066. 799 |0. 0522 |143. 3388 | |Tuesday-Wednesday |237. 71 |2. 575 |1066. 799 |0. 0520 |142. 7070 | |Tuesday-Thursday |71. 02 |2. 575 |1066. 799 |0. 0519 |142. 5147 | |Tuesday-Friday |90. 88 |2. 575 |1066. 799 |0. 0522 |143. 3114 | |Wednesday-Thursday |166. 69 |2. 575 |1066. 99 |0. 0519 |142. 6246 | |Wednesday-Friday |146. 83 |2. 575 |1066. 799 |0. 0522 |143. 3938 | |Thursday-Friday |19. 86 |2. 575 |1066. 799 |0. 0521 |143. 2015 | |Table 3. Deviation of Actual from Expected Rank Differences | |Monday-Tuesday |-102. 12 | | | |Monday-Wednesday |54. 308 | | | |Monday-Thursday |-112. 190 | | | |Monday-Friday |-93. 099 | | | |Tuesday-Wednesday |95. 03 | | | |Tuesday-Thursday |-71. 495 | | | |Tuesday-Friday |-52. 431 | | | |Wednesday-Thursday |24. 065 | | | |Wednesday-Friday |3. 436 | | | |Thursday-Friday |-123. 41 | | | Table 4 represents the yearly distribution of mean returns on S;P CNX Nifty for different days of the week from 1994 to 2008. Also to test whether these differences in the mean returns on different days are statistically significant or not, the non parametric ‘H’ statistics has been used. The table value of the chi-square (? 2) distribution at 1 percent level of significance is 13. 277 and at 5 percent level of significance is 9. 488. If we look at year wise KW statistics, up to year 1999 ‘H’ statistics is highly significant and after 1999 it is insignificant. |Table 4.Yearly Distribution of Mean Returns on S;P CNX Nifty by Day-of-the-Week | |(January 1994 – December 2008) | | | | | |Year/Day |Monday |Tuesday |Wednesday |Thursday |Friday |KW Statistics | |1994 |0. 47012 |-0. 16573 |-0. 36687 |0. 01075 |0. 32745 |9. 945** | |1995 |-0. 51580 |-0. 33583 |0. 25709 |-0. 6627 |0. 11756 |11. 145** | |1996 |-0. 35599 |-0. 35342 |0. 53600 |0. 18662 |0. 07796 |10. 114** | |1997 |-0. 46253 |-0. 14396 |1. 04706 |-0. 16222 |-0. 06761 |19. 917* | |1998 |-0. 12914 |-0. 52606 |0. 78280 |-0. 15417 |-0. 22507 |13. 245** | |1999 |-0. 00553 |0. 07532 |0. 98097 |0. 10327 |-0. 00305 |14. 48* | |2000 |-0. 16997 |-0. 28629 |0. 49777 |-0. 10239 |-0. 16992 |4. 989 | |2001 |-0. 21325 |0. 11775 |0. 30553 |0. 08010 |-0. 60214 |4. 987 | |2002 |0. 00508 |-0. 15830 |-0. 05939 |0. 07054 |0. 22584 |4. 226 | |2003 |0. 15214 |0. 13598 |0. 26208 |0. 13987 |0. 38014 |2. 323 | |2004 |-0. 4126 |0. 26824 |0. 04482 |0. 02138 |0. 07889 |1. 236 | |2005 |0. 29696 |0. 04875 |0. 02291 |0. 08195 |0. 18711 |1. 806 | |2006 |-0. 09098 |0. 01140 |0. 22203 |0. 22753 |0. 33653 |1. 198 | |2007 |0. 24310 |0. 32425 |0. 02874 |0. 30801 |0. 02442 |2. 139 | |2008 |-0. 36369 |-0. 13064 |-0. 04547 |-0. 5441 |-0. 24632 |1. 46 | | All Years |-0. 08563 |-0. 07615 |0. 30300 |0. 01895 |0. 03221 |21. 278* | | | | | | | | | |*Significant at 1% level | | | |**Significant at 5% level | | |Further entire study period has been divided into two sub periods: Period 1 (January 1994 to Decemeber 2001) and period 2 (January 2002 to December 2008). Period 1 represents the time when weekly settlement was operational and during this time frame NSE had fixed settlement day – Tuesday. Period 2 represents the time period when rolling settlement was introduced in place of weekly settlement cycle. | | | | | | | | |Table 5.Mean Daily returns on S;P CNX Nifty by Day of the Week for Sub-Periods | |   |Monday |Tuesday |Wednesday |Thursday |Friday |KW Statistics | |Subperiod-1 |-0. 17276 |-0. 20228 |0. 50504 |-0. 01304 |-0. 06810 |42. 752* | |Subperiod-2 |0. 00197 |0. 05294 |0. 09734 |0. 03923 |0. 12735 |2. 84 | | | | | | | | | | | |*Significant at 1% level | | | It is analyzed from the above table that in sub period 1 (1994 to 2001) all days except Wednesday gives negative rate of retu rn. This is clearly the impact of Tuesday settlement that returns on Tuesday are lowest and on Wednesday it is highest positive. It means beginning of settlement cycle ives maximum returns while last day of settlement cycle called settlement day gives lowest returns. Also a very high value of KW statistics i. e. 42. 752 represents a high degree of seasonality in sub period 1 (before rolling settlement time period). To bring more frequency in the transactions and to bring Indian markets at par with the international markets rolling settlement on T+5 basis was introduced in December 2001. So in sub period 2 when rolling settlement was introduced, returns on all the days have become positive and Friday is giving maximum returns and Monday is giving lowest returns.This hints towards the presence of some sort of weekend seasonality. But the value of ‘H’ statistics is very low i. e. 2. 684. From this it can be inferred that the return distributions are not significantly diffe rent across the week days and the null hypothesis stands rejected in the sub period 2. Thus it may be concluded that with the introduction of rolling settlement on NSE the stock markets have become more efficient. CONCLUSION During the period 1994 to 2008, S;P CNX Nifty index recorded highest positive returns on Wednesday and most negative returns on Monday with highest volatility on Monday and Friday.It means week start and week end tend to be more volatile in Indian stock market. Also it has been analyzed that Wednesday is giving significantly higher returns than other days of the week which points towards the existence of Wednesday effect in Indian stock market. There was presence of day of the week effect in pre-rolling settlement period which gradually phased away with the introduction of the rolling settlement. Markets have become efficient after rolling settlement has been introduced.So in present scenario we can’t rely on a trading strategy formulated on the basis of historical return movements on different days to earn abnormal returns as seasonality has disappeared in the recent years of the study period.

Saturday, September 14, 2019

Hydraulic Machines

30 CHAPTER 5 TURBINES 5. 1 Introduction Hydraulic turbines are the machines which use the energy of water and convert it to mechanical energy. The mechanical energy developed by a turbine is used in running an electric generator which is directly coupled to the shaft of the turbine. The electric generator thus develops electric power, which is known as hydro-electric power. 5. 2 Elements of Hydraulic Power Plants Fig. 5. 1 General Layout of a Hydraulic Power Plant 31 Fig. 5. 1 shows a general layout of hydraulic power plant, in which an artificial storage reservoir formed by constructing a dam has been shown. 5. 3General Classification of Turbines Turbines are hydraulic machines that convert energy into rotating mechanical energy which in turn generators to produce electrical energy. Originally developed from the water wheels, hydraulic turbines are the prime mortars of importance in modern water power development. According to their hydraulic action, turbines are broadly divided int o two classes. (1) Impulse Turbine: Impulse turbines are more efficient for high heads. At the inlet to the turbine runner, pressure head can be completely converted into kinetic head in the form of a jet of water issuing from one or more nozzles.The free jet will be at atmospheric pressure before as well as after striking the vanes. The turbines are regulated by nozzles which may be a simple straight flow type or a deflector type. The impulse turbines are commonly represented by Pelton Wheels. Turgo turbine is also an impulse turbine but with different buckets, when compared with pelton. Turgo and cross flow turbines are relatively new developments in this class. The main advantages of these turbines are: †¢ They can be easily adopted to power variation with almost constant efficiency. †¢The penstock overpressure and the runner overspeed control are easier. †¢ The turbine enables an easier maintenance. †¢ Due to the jet the manufacturer of these turbines impose a better solid particle control, conducting, consequently, to a lower abrasion effect. (2) Reaction Turbine: A turbine can be made to rotate under the action of water flowing under pressure through the runner. In such turbines the penstocks, the inlet passage to the runner, passage between the runner vanes, all form a continuous passage for the flow under a pressure which continuously decreases from inlet to outlet.The turbine runner directly converts both kinetic energy as well as the pressure energy into mechanical energy. Reaction turbines are represented in modern practice by two principal types: the Francis turbine where the flow is directed radial to the runner axis and the Propeller type 32 where the flow is axial to the runner axis. Propeller turbines may be fixed blade or adjustable blade types. Kaplan turbine has adjustable blades. The main advantages of these turbines are: †¢ It needs lesser installation space. †¢ It provides a greater net head and a better prot ection against downstream high flood levels. It can have greater runner speed. †¢ It can attain greater efficiencies for high power values. In order to distinguish different turbines, the hydraulically salient features like pressure, head, flow direction and magnitude, speed and power etc. The general classification of hydraulic turbines is illustrated in Fig. 5. 2. Hydraulic Turbines Impulse Turbines Pelton Turgo Reaction Turbines Cross-Flow Fixed -Blade Propeller Kaplan Francis Tubular Deriaz Bulb Fig. 5. 2 General Classification of Turbines 5. 4 Number of Units It is normally cost effective to have a minimum number of units at a given small ydropower installation. Multiple units may, however, be necessary from the operational point of view so that even one unit breaks down or is in the routine maintenance, the power generation can be achieved to a certain extent. The efficiency curves of turbines show that the 33 efficiency of power generation from hydraulic turbines conside rably decreases at low flow ratios or power ratios. In multiple units, it is possible to maintain the higher efficiency even in low flows and the low loads by running a certain number of the units at a time depending upon the available discharge and the load demand.Multiple units thus, make the most effective use of water where the flow as well as the load variations are significant. 5. 5 Limits of Use of Turbine Types The selection of best turbines for any particular small hydropower site depends on the site characteristics, the dominant beings the head and the available flow. There are some limits on the range of these parameters in the selection of turbines. Each turbine type is best suited to a certain range of pressure head and the flow rate. For instance, Pelton wheels operate with low flows discharged under great pressures where as Propeller turbines are effective in high flows under low heads.Francis turbines fall in the medium category covering a wide range of different hea ds and discharges. The common practice of SHP systems is to develop standard unit sizes of equipment that will operate over a range of heads and flows. Either charts or nomographs are used to select appropriate units for site specific application. One such chart showing the head-flow range of normal SHP schemes applicable to each type of turbine is given in Fig5. 3. The graph also indicates the approximate power generation for each combination of the head and the discharge applicable to SHP schemes. Fig. . 3 Head-Flow Ranges for Different Turbines 34 5. 6 Pelton Wheel Pelton wheel is well suited for operating under high heads. A pelton turbine has one or more nozzles discharging jets of water which strike a series of buckets mounted on the periphery of a circular disc. The runner consists of a circular disc with a number of buckets evenly spaced round its periphery. The buckets have a shape of a double semi-ellipsoidal cups. The pelton bucket is designed to deflect the jet back thro ugh 165 ° which is the maximum angle possible without the return jet interfering with the next bucket.Fig. 5. 4 Pelton bucket General arrangement of a pelton wheel is shown in the Fig. 5. 5. For SHP schemes, Pelton wheels are easier to fabricate and are relatively cheaper. The turbines are in general, not subjected to the cavitation effect. The turbines have access to working parts so that the maintenance or repairs can be effected in a shorter time. Fig. 5. 5 General Arrangement of a Pelton Wheel 35 Traditionally, micro hydro pelton wheels were always single jet because of the complexity and the cost of flow control governing of more than one jet.Advantages of multi-jet: -Higher rotational speed -Smaller runner -Less chance of blockage Disadvantages of multi-jet: -Possibility of jet interference on incorrectly designed systems -Complexity of manifolds 5. 7 Francis Turbine Francis turbine is a mixed flow type, in which water enters the runner radially at its outer periphery and le aves axially at its center. Fig. 5. 6 illustrates the Francis turbine. The runner blades are profiled in a complex manner and the casing is scrolled to distribute water around the entire perimeter of the runner.The water from the penstock enters a scroll case which completely surrounds the runner. The purpose of the scroll case is to provide an even distribution of water around the circumference of the turbine runner, maintaining an approximately constant velocity for the water so distributed. The function of guide vane is to regulate the quantity of water supplied to the runner and to direct water on to the runner at an angle appropriate design. A draft tube is a pipe or passage of gradually increasing cross sectional area which connects the runner exit to the tail race. Fig. 5. 6 Francis Turbine 36 . 8 Kaplan Turbine It is an axial flow turbine which is suitable for relatively low heads. From Fig. 5. 7, it will be seen that the main components of Kaplan turbine such as scroll casi ng, guide vanes, and the draft tube are similar to those of a Francis turbine. Fig. 5. 7 5. 9 Kaplan Turbine Specific Speed The specific speed of any turbine is the speed in r. p. m of a turbine geometrically similar to the actual turbine but of such a size that under corresponding conditions it will develop 1 metric horsepower when working under unit head. Ns = NP H5/ 4 †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 1) where Ns = specific speedP = power in HP 5. 10 Characteristic Curves The turbines are generally designed to work at particular values of H,Q,P,N and ? o which are known as the designed conditions. It is essential to determine exact behaviour of the turbines under the varying conditions by carrying out tests either on the actual turbines or on their small scale models. The results of these tests are usually graphically represented and the resulting curves are known as characteristic curves. 37 -constant head characteristic curves -constant speed characteristic curves -constan t efficiency characteristic curvesIn order to obtain constant head characteristics curves the tests are performed on the turbine by maintaining a constant head and a constant gate opening and the speed is varied by changing the load on the turbine. A series of values of N are thus obtained and corresponding to each value of N, discharge Q and the output power P are measured. A series of such tests are performed by varying the gate opening, the head being maintained constant at the previous value. From the data of the tests the values of Qu, Pu, nu and ? o are computed for each gate opening. Then with Nu as abscissa the values ofQu, Pu and ? o for each gate opening are plotted. The curves thus obtained for pelton wheel and the reaction turbines for four different gate openings are shown in Fig. 5. 8. Fig. 5. 8 Constant head characteristics for Pelton wheel and reaction turbines 38 5. 11 Cavitation in turbines When the pressure in any part of the turbine reaches the vapour pressure of the flowing water, it boils and small bubbles of vapour form in large numbers. These bubbles are carried along by the flow, and on reaching the high pressure zones these bubbles suddenly collapse as the vapour condenses to liquid again.The alternate formation and collapse of vapour bubbles may cause severe damage to the surface which ultimately fails to fatigue and the surface becomes badly scored and pitted. This phenomenon is known as cavitation. In order to determine whether cavitation will occur in any portion of the turbine, D. Thomas has developed a dimensionless parameter called Thomas'cavitation factor ? which is expressed as ?= Ha ? Hv ? Hs H †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 2) where Ha = atmospheric pressure head Hv = vapour pressure head Hs = suction pressure head For Francis turbines: Critical cavitation factor ? c = 0. 625 (Ns/444)2 †¦Ã¢â‚¬ ¦.. (5. 3) For Propeller turbines: ? c = 0. 28 + [ Example 5. 1 1 Ns 3 ( )] 7. 5 444 †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. (5. 4) Est imate the maximum height of straight conical draft tube of a 18000 h. p. Francis turbine running at 150 r. p. m under a net head of 27 m. The turbine is installed at a station where the effective atmospheric pressure is 10. 6 m of water. The draft tube must sink at least 0. 77 m below the tail race. Ns = NP H5/ 4 = 327 39 ?c = 0. 625 (Ns/444)2 = 0. 339 Cavitation factor ? = Ha -Hv -Hs H Ha -Hv = 10. 6 m, H =27 m 0. 339 = 10. 6 -Hs 27 Hs = 1. 45 m Max length of the draft tube = 1. 45 + 0. 7 = 2. 22 m 5. 12 Governing of Turbines All the modern turbines are directly coupled to the electric generators. The generators are always required to run at constant speed irrespective of the variations in the load. This constant speed N of the generator is given by the expression N= 60 f p †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. (5. 5) where f = frequency (usually 50) p = numbers of pairs of poles 5. 13 Water Hammer A gate or valve at the end of the penstock pipe controls the discharge to the turbine. As s oon as this governor regulated gate opening is altered, the pipe flow has to be adjusted to the new magnitude of flow.In doing so, there are rapid pressure oscillations in the pipe, often accompanied by a hammering like sound. Hence this phenomenon is called as water hammer. 5. 14 Jet Speed The velocity of flow of the jet depends upon the total net head H at the base of the nozzle and is given by the nozzle equation: v = C v ? 2gH where the discharge coefficient velocity of the nozzle is taken as 0. 95. †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 6) 40 5. 15 Bucket speed V= ? DN 60 †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 7) The bucket speed should be half of the jet speed. In practice, losses in the turbine cause the maximum efficiency to occur at slightly less than a half, typically 0. 46. V =0. 6 v 5. 16 Design of Pelton Wheel Runner diameter: Runner diameter can be found out from the rpm equation. D= 38 ? H N †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. (5. 8) where N = runner speed(rpm) H = net head Nozzle diameter: The nozzle diameter is given by the nozzle equation: d = 0. 54 ? Q 0. 5 1 ? 0. 25 H n jet †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. (5. 9) Jet ratio: Jet ratio D/d is a size parameter for the turbine. It has a value in a range of 10 to 24. For the high efficiency Pelton wheel design, the ratio of the runner diameter to the nozzle should be more than 9. Number of buckets: The number of buckets required for the efficient operation of the Pelton turbine is calculated as:N buc = 0. 5 ? D + 15 d †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. (5. 10) In practice, the selection and the detail design of the turbine units are carried out by the manufactures based on the model performances. 41 Example 5. 2 Powerhouse is equipped with a vertical shaft pelton turbine. The generator is provided with 6 pairs of poles. Design discharge is 1. 4 m3/s and net head is 425 m. The turbine will provide 6500 hp. Take coefficient of nozzle as 0. 95. Determine (a) the specific speed (b) velocity of jet (c) jet diameter (d) pitch circle diameter of the wheel (e) number of buckets (a) N= 60 f p = 60 x 50/6 = 500 rpmNs = = NP H5/ 4 500 6500 4255 / 4 = 20. 9 Use single jet pelton turbine (b) velocity of jet v = C v ? 2gH = 0. 95 ? 2Ãâ€"9. 81Ãâ€"425 = 86. 75 m/s (c) jet diameter d = 0. 54 ? = 0. 54 ? Q 0. 5 1 ? 0. 25 H n jet 1. 4 0. 5 425 0. 25 ? = 0. 14 m =14 cm 1 1 42 (d) pitch circle diameter D= 38 ? H N = 1. 57 m (e) Number of buckets N buc = 0. 5 ? N buc = 0. 5 ? D + 15 d 1. 57 + 15 0. 14 = 20. 6 = 21 5. 17 Work done of Pelton Wheel In turbines, the water flows on to the runner, which itself is rotating with a certain speed. The water flows over the runner and leaves the runner at its outlet point.We can speak of absolute velocity of water before it flows in the runner, the relative velocity of water w. r. t the runner and again the absolute velocity of water after it has left the runner. In order to ascertain the relationship between these velocities, the velocity vector diagram prove to be very useful. Fig. 5. 9 shows the velocity triangles at the tips of the bucket of a pelton wheel. At the outlet tip velocity triangles are different depending upon the magnitude of u corresponding to which it is slow, medium or fast runner. Inlet velocity diagram VVri Vai =Vwi 43 Outlet velocity diagram V Vwo ? ? Vfo Vro Vao Fig. 5. 9 Velocity triangles V = bucket velocity Vai = absolute velocity of jet at inlet tip Vai = Cv 2 gH1 Vao = absolute velocity of jet at outlet tip Vri = relative velocity of jet at inlet = Vai-V Vro = relative velocity of jet at outlet = k. Vri Vwi = velocity of whirl at inlet =Vai Vwo = velocity of whirl at outlet = V-VroCos ? Vfo = velocity of flow at outlet Mass/sec m =? Q =? a Vai=? ?/4 d2 Vai †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 11) Workdone on the bucket/sec (power developed by turbine) P = m (Vwi -Vwo) V †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 12)Maximum hydraulic efficiency ? h max = 1 (1 + kCos? ) 2 †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(5. 13) The hydraulic efficiency is maximum when the bucket speed is equal to half of the velocity of jet. 44 Example 5. 3 The head available at entrance to the nozzle supplying a pelton wheel is 300 m and the coefficient of velocity for the nozzle is 0. 98. The wheel diameter is 1. 8 m and the nozzle diameter is 125 mm. The buckets deflect the jet through 165 °. Assuming the relative velocity of the jet is reduced by 16%, calculate the theoretical speed in rev per min for the maximum hydraulic efficiency.What is the hydraulic efficiency when running at this speed, and what is the power developed? Deflection angle =165 ° = (180- ? ) ? = 15 ° k = 0. 84 hf hn H'=Vai2/2g H For max hydraulic efficiency V/Vai =0. 5 Vai = Cvv2gH1 = 75 m/s V =Vai/2 = 37. 5 m/s V =? DN/60 N =60V/? D = 398 rpm ?hmax = 1/2 (1+ k Cos ? ) = 90. 55 % mass/sec = m = ? Q = ? ?/4 d2 Vai = 920 kg/sec H1 45 Inlet diagram: V Vri From velocity diagram Vwi = Vai =75 m/s Vri = Vai- V =37. 5 m/s Vwi = Vai Outlet diagram: Vwo = V -Vro Cos ? V = V – k Vri Cos ? Vwo Vro Power = m V ( Vwi -Vwo) = 234600 Watts Vao =7 m/s 46 CHAPTER 6CENTRIFUGAL PUMP 6. 1 Introduction Centrifugal pumps are classified as rotodynamic type of pumps in which dynamic pressure is developed which enables the lifting of liquids from a lower to a higher level. The basic principle on which a centrifugal works is that when a certain mass of liquid is made to rotate by an external force, it is thrown away from the central axis of rotation and a centrifugal head is impressed which enable it to rise to a higher level. Now, if more liquid is constantly made available at the centre of rotation, a continuous supply of liquid at a higher level may be ensured.Since in these pumps the lifting of the liquid is due to centrifugal action, these pumps are called ‘centrifugal pumps'. 6. 2 Advantages of centrifugal pumps over reciprocating pumps The main advantage of a centrifugal pump is that its discharging capacity is very much greater than a reciprocating pump which can handle relatively small quantity of liquid only. A centrifugal pump can be operated at very high speeds without any danger of separation and cavitation . The maintenance cost of a centrifugal pump is low and only periodical check up is sufficient .But for a reciprocating pump the maintenance cost is high because the parts such as valves etc. , may need frequent replacement. 6. 3 Component Parts of a Centrifugal Pump The main component parts of a centrifugal pump are: -impeller -casing -suction pipe -delivery pipe 47 Fig. 6. 1 Component part of a centrifugal pump 6. 4 Workdone by the Impeller The expression of the workdone by the impeller of a centrifugal pump on the liquid flowing through it may be derived in the same way as for a turbine. The liquid enters the impeller at its centre and leaves at its periphery. Fig. 6. shows a portion of the impeller of a centrifugal pump with one vane and the velocity triangles at the inlet and outlet tips of the vane. V is absolute velocity of liquid, u is tangential velocity of th e impeller, Vr is relative velocity of liquid, Vf is velocity of flow of liquid, and Vw is velocity of whirl of the liquid at the entrance to the impeller. Similarly V1,u1,Vr1,Vf1 and Vw1 represent their counterparts at the exit point of the impeller. 48 Fig. 6. 2 Velocity triangles for an impeller vane ? = the impeller vane angle at the entrance ? = the impeller vane angle at the outlet = the angle between the directions of the absolute velocity of entering liquid and the peripheral velocity of the impeller at the entrance ? = the angle between the absolute velocity of leaving liquid and the peripheral velocity of the impeller at the exit point Work done per second by the impeller on the liquid may be written as Work done = W ( Vw1 u1 – Vw u) ————-(6. 1) g where W kg of liquid per second passes through the impeller. Since the liquid enters the impeller radially ? = 90 and hence Vw = 0. Thus equation (6. 1) becomes Work done = W (Vw1u1) —â⠂¬â€Ã¢â‚¬â€Ã¢â‚¬â€-(6. ) g 6. 5 Head of a Pump The head of a centrifugal pump may be expressed in the following two ways: (a) Static head (b) Manometric head (or total head or gross head) 49 Fig. 6. 3 Head on a centrifugal pump (a) Static Head Static head is the vertical distance between the liquid surfaces in the pump and the tank to which the liquid is delivered by the pump. Static head (or lift) Hs = hs + hd where hs = static suction lift hd = static delivery lift †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. (6. 3) 50 (b) Manometric Head Manometric head is the total head that must be produced by the pump to satisfy external requirements.If there are no energy losses in the impeller and the casing of the pump, then the manometric head Hm will be equal to the energy given to the liquid by the V ? 1u1 g impeller, i. e Hm = . But if losses occur in the pump then V ? 1u1 ? losses of head in the pump g †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. (6. 4) Applying Bernoulli’s equation between the points, O at the liqui d surface in the pump and 1 in the suction pipe just at the inlet to the pump (i. e. , at the centre line of the pump), the following expression is obtained if the liquid surface in the sump is taken as datum. 0= p s Vs2 + + hs + h f s ? 2g ps Vs2 ? [ + hs + h fs ] 2g ? †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. (6. 5) where ps is the pressure at point l ; Vs is the velocity of flow in the suction pipe ; hs is the suction lift and hfs is the head loss in the suction pipe which includes the head loss due to friction and the other minor losses. It may however be pointed out that if the pump is situated below the level of the liquid surface in the sump, hs will be negative. Equation (6. 5) indicates that at the inlet to the pump there is always a suction or vacuum pressure developed which will be recorded by the vacuum gauge provided at this point as shown in Fig. . 3. The head expressed by equation (6. 5) is called the suction head of the pump. Also, applying Bernoulli’s equation between points 1 and 2, which is just at the outlet of the impeller and is assumed to be at the same level as point 1, then since the impeller imparts a head equal to (Vw1u1/g) to the liquid the following expression is obtained: p s V s2 V? 1u1 p 2 V12 + + = + + hLi ? 2g g ? 2g †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. (6. 6) where p2 is the pressure and V1 is the absolute velocity of the liquid leaving the impeller and hLi is the loss of head in the impeller. 51 6. Specific Speed of Centrifugal Pumps In order to compare the performance of different pumps, it is necessary to have some term which will be common to all centrifugal pumps. The term used for this purpose is the specific speed. The specific speed of a centrifugal pump is the speed at which the specific pump must run to deliver unit quantity against unit head, the efficiency being the same as the actual pump. Ns = NQ H 3/ 4 †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦(6. 7) where Ns= specific speed N = rotational speed(rpm) H = total head 6. 7 Performance of Pumps- Charact eristic CurvesA pump is usually designed for one speed, flow rate and head in actual practice, the operation may be at some other condition of head on flow rate, and for the changed conditions, the behaviour of the pump may be quite different. Therefore, in order to predict the behaviour and performance of a pump under varying conditions, tests are performed and the results of the tests are plotted. The curves thus obtained are known as the characteristic curves of the pump. The following three types of characteristic curves are usually prepared for the centrifugal pumps : a) Main and operating characteristics. (b) Constant efficiency or Muschel curves . (c) Constant head and constant discharge curves. Main and Operating Characteristics In order to obtain the main characteristic curves of a pump it is operated at different speeds. For each speed the rate of flow Q is varied by means of a delivery valve and for the different values of Q the corresponding values of manometric head Hm, shaft H. P. , P , and overall efficiency ? are measured or calculated. The same operation is repeated for different speeds of the pump. Then Q v/s Hm ; Q v/s P and Q v/s ? urves for different speeds are plotted, so that three sets of curves, as shown in Fig. 6. 4 are obtained, which represent the 52 main characteristics of a pump. The main characteristics are useful in indicating the performance of a pump at different speeds. During operation a pump is normally required to run at a constant speed, which is its designed speed, (same as the speed of the driving motor). As such that particular set of main characteristics which corresponds to the designed speed is mostly used in the operations of a pump and is, therefore, known as the operating characteristics.A typical set of such characteristics of a pump is shown in Fig. 6. 5 Fig. 6. 4 Main characteristics of a centrifugal pump Fig. 6. 5 Operating characteristic curves of a centrifugal pump 53 6. 8 Parallel or Series Operation of Pu mps Pumps in series Centrifugal pumps generate a relatively low head delivering a fairly high rate of discharge. Normally a pump with a single impeller can be used to deliver the required discharge against a maximum head of about 100 m. But if the liquid is required to be delivered against a still larger head then it can be done by using two or more pumps in series. Fig. 6. 6 Three stage centrifugal pumpIf the required head is more than that can be provided by one pump, the pumps are connected in series. The same discharge passes through both pumps but the head developed by one pump add the other. The total head developed is obtained by adding together the value of the head of each pump corresponding to the relevant discharge. Pumps in Parallel The multi-stage pumps or the pumps in series as described earlier are employed for delivering a relatively small quantity of liquid against very high heads. However, when a large quantity of liquid is required to be pumped against a relativel y small head, then it may 4 not be possible for a single pump to deliver the required discharge. In such cases two or more pumps are used which are so arranged that each of these pumps working separately lift the liquid from a common sump and deliver it to a common collecting pipe through which it is carried to the required height Fig. 6. 7. Since in this case each of the pumps deliver the liquid against the same head, the arrangement is known as pumps in parallel. If Q1, Q2, Q3†¦.. , Qn are the discharging capacities of n pumps arranged in parallel then the total discharge delivered by these pumps will beQt = (Q1+Q2+Q3+†¦Ã¢â‚¬ ¦+Qn) †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. (6. 8) If the discharging capacity of all the n pumps is same, equal to Q , then the total discharge delivered by these pumps will be Qt = nQ Fig. 6. 7 Two centrifugal pumps arranged in parallel 55 A centrifugal pump, having four stages in parallel, delivers 11m3/min of Example 6. 1 liquid against a head of 24. 7m , the diameter of the impeller being 225mm and the speed 1700 rpm. A pump is to be made up with a number of identical stages in series, of similar constriction to those in the first pump, to run at 1250 rpm, and to deliver 14. 5 m3/min, against a head of 248m.Find the number of stages required for the second pump. 1st Pump 2nd Pump Q = 11m3/min Q = 14. 5m3/min H = 24. 7 m H = 248 m N = 1700 rpm N =1250 rpm D = 225 mm Specific speed N s = NQ H 3/ 4 Q for one pump = 11/4 = 2. 75 m3/min Ns = 1700 2. 75 24. 7 3 / 4 = 254 For 2nd pump, with identical stages in series i. e multi-stage pump, if each stage is similar to those of each stage is similar to those of the first pump. The specific speed of each stage Ns = 254 Ns = 254 = NQ H 3/ 4 1250 14. 5 H 3/ 4 H = 49. 64 m Total head required = 248 m No of stages required = 248/49. 64 = 5 stages 56 CHAPTER 7DIMENSIONAL ANALYSIS, HYDRAULIC SIMILITUDE AND MODEL INVESTIGATION 7. 1 Dimensional Analysis Dimensional analysis is a mathematical method of obtaining the equations, changing units, determining a convenient arrangement of variable of a physical relation. In an equation expressing a physical relationship between quantities, absolute numerical and dimensional equality must exit. In general, all such physical relationships can be reduced to the fundamental quantities of mass M, length L and time T. It is a based on the assumption that the phenomenon can be expressed by a dimensionally homogeneous equation, with certain variable.The dimensional analysis is widely used in research work for developing design criteria and also for conducting model tests. 7. 2 Dimensions and Units All physical quantities are measured by comparison. This comparison is always made with respect to some arbitrarily fixed value for each independent quantity, called dimension(e. g. , length, mass, time, etc. ). Since there is no direct relationship between these dimensions, they are called fundamental dimensions. Some other quantities such as area , volume, velocity, force etc. can not be expressed in terms of fundamental dimensions and thus may be alled derived dimensions. There are two systems for fundamental dimensions namely FLT (i. e force, length, time) and MLT (i. e. , mass, length, time). One common system employed in dimensional analysis is the M,L,T system. Table is a listing of some of the quantities used in fluid flow, together with their symbols and dimensions. 57 Quantity Symbol Dimensional Form Length l L Time t T Mass m M Velocity v L T-1 Acceleration a L T-2 Force F M L T-2 Pressure P M L-1 T-2 Discharge Q L3 T-1 Power P M L2 T-3 W,E M L2 T-2 Density ? M L-3 Dynamic viscosity  µ M L-1 T-1 Kinematic viscosity ? L2 T-1 Surface tension M T-2 Work,energy 7. 3 Methods of Dimensional Analysis The methods of dimensional analysis are: -Buckingham's ? theorem -Ralyeigh's method Buckingham's ? Theorem If there are ‘n' variables in a dimensionally homogeneous equation, and if these variables contain ‘m' fu ndamental dimensions such as (M,L,T) , they may be grouped into (nm) non-dimensional independent ? terms. Mathematically, if a variable x1 depends upon independent variables x2, x3,x4, †¦. ,xn, the functional equation may be written as x1 = f (x2, x3, x4, †¦. , xn) The equation may be written in its general form as 58 f1 ( x1, x2, x3,†¦Ã¢â‚¬ ¦. xn) = C In this equation there are ‘n' variables. If there are ‘m' fundimental dimensions, the according to ? theorem f2 ( ? 1,? 2,? 3,†¦.. , ? n-m ) = C1 e. g Q = f (d,H, µ,? ,g) f1 (Q, d, H,  µ, ? , g) = C n = 6; m = 3; (n-m) = 3 f2 ( ? 1, ? 2, ? 3) = C1 Procedure 1. First of all, write the functional relationship with the given data. 2. Then write the equation in its general form. 3. Choose ‘m' repeating variables and write separate expressions for each term. Every ? term will contain the repeating variables and one of the remaining variables. The repeating variables are written in exponential form . 4.With the help of the principle of dimensional homogeneity, find out the values of the exponents by obtaining simultaneous equations. 5. Substitute the value of these exponents in the ? term. 6. After the ? terms are obtained, write the functional relation in the required form. e. g Q = f ( d, H,  µ, ? , g) f1 (Q, d, H,  µ, ? , g) =C n = 6 , m = 3 , (n-m) = 3 f2 (? 1,? 2,? 3)=C1 Choose ? , g, d as repeating variable, ?1 = ? a1 gb1 dc1 Q ? 2 = ? a2 gb2 d c2 H ? 3 = ? a3 gb3 dc3  µ 59 Selection of Repeating Variable 1. The variables should be such that none of them is dimensionless. 2. No two variables should have the same dimensions. . Independent variables should be as far as possible, be selected as repeating variable. ? > fluid property ? > flow characteristics l > geometric characteristics Example 7. 1 A V-notch weir is a vertical plate with a notch angle ? cut into the top of it and placed across an open channel. The liquid in the channel is backed up and forced to flow through the notch. The discharge Q is some function of the elevation H of upstream liquid surface above the bottom of the notch. In addition it depends upon gravity and upon the velocity of approach Vo to the weir. Determine the form of discharge equation: ?V ? Q = gH 5/2 f ? ,? ? ? gH ? ? ? Q = f (H, g , Vo , ? ) f1 ( Q, H ,g ,Vo, ? ) = C Choose g and H as repeating variables n = 5; n-m =3 ; m=2 ?1 = Ha1 gb1 Q = (L)a1 (LT-2)b1 L3 T-1 ?2 =Ha2 gb2 Vo = (L)a2 (LT-2)b2 LT-1 ?3 = ? (M)o (L)o (T)o = (L)a1 (LT-2)b1 L3 T-1 a1+b1+3 =0 ? a1 = -5/2 -2b1-1 =0 ? b1 = -1/2 ?1 = H-5/2 g-1/2 Q = Q vg H 5/2 (M)o (L)o (T)o = (L)a2 (LT-2)b2 L T-1 a2 = -1/2 60 b2 = -1/2 ?2 =H-1/2 g-1/2 Vo= Vo vgH Q f2 ( gH 5/ 2 Q gH 5/ 2 , Vo ,? gH ) = C1 Vo ,? gH ) Vo ,? gH ) =f( Q = gH 5/2 f ( Example 7. 2 Q = VD 2 f [ Prove that the discharge over a spillway is given by the relation gD H ,] V D where V= velocity of flowD = depth of throat H = Head of water g = Acceleration due to gravity Q= f (V,D,H,G) f1 (Q,V,D,H ,G) = C Choose V and D as repeating variables n = 5, m =2, n-m =3 ?1= Va1 Db1 Q = (LT-1)a1 (L)b1 (L3T-1) ?2 = Va2 Db2 H = (LT-1)a2 (L)b2 (L) ?3 = Va3 Db3 g = (LT-1)a3 (L)b3 (LT-2) M0L0T 0 = (LT-1)a1 (L)b1 (L3T-1) 0 = -a1-1 ; a1 = -1 0 = a1+b1+3 ; b1= -2 ?1 = V -1 D -2 Q 61 ?1 = Q VD2 M0L0T 0 =(LT-1)a2 (L)b2 (L) 0 = -a2 a2+b2+1 =0 ; b2 = -1 ?2 = V0 D-1 H = H/D M0L0T 0 = (LT-1)a3 (L)b3 (LT-2) 0 = -a3-2 ; a3 = -2 0 = a3+b3+1 ; b3 =1 ?3 = V-2 D g gD V = f2 ( gD H , )=0 VD 2 D V Q VD 2 Q , = f( gD H ,) V D Q = VD 2 f ( 7. 4 D H ,) V D HYDRAULIC MODELS Hydraulic models, in general, may be either true models or distorted models. True models have all the significant characteristics of the prototype reproduced to scale (geometrically similar) and satisfy design restrictions (kinematic and dynamic similitude). Model-prototype comparisons have clearly shown that the correspondence of behaviour is often well beyond expected limitations, as has been attested by the successful operation of many s tructures designed from model tests. 7. 5 Hydraulic Similitude To know the complete working and behaviour of the prototype, from its model, there hould be a complete similarity between the prototype and its scale model. This similarity is 62 known as hydraulic similitude. From the subject point of view, the following three types of hydraulic similitude are important. (1) Geometric similitude (2) Kinematic similitude (3) Dynamic similitude GEOMETRIC SIMILITUDE The model and the prototype are identical in shape, but differ only in size. (The ratios of all the corresponding linear dimensions are equal) . Let L = Length of the prototype B = Breadth of the prototype D = Depth of the prototype l,b,d = corresponding values of the model L Linear ratio Lr =Area ratio Ar = ( Volume ratio Vr = ( l = BD = bd L B D )2 = ( )2 = ( )2 l b d L B D ) 3 = ( ) 3 = ( )3 l b d KINEMATIC SIMILITUDE The model and the prototype have identical motions. ( The ratios of the velocities at corresponding points a re equal) Let V1 = velocity of liquid in prototype at point 1 V 2 = velocity of liquid in prototype at point 2 v1,v2 = corresponding values of the model Velocity ratio Vr = V1 V2 = = †¦.. v1 v 2 DYNAMIC SIMILITUDE The model and prototype have identical forces. (The ratios of the corresponding forces acting at corresponding points are equal). F Force ratio Fr = 1 = f1 F2 †¦.. f2 63 7. 6 CLASSIFICATION OF MODELS (1) Undistorted model (2) Distorted model Undistorted model A model which is geometrically similar to the prototype is known as undistorted model. Distorted model Model does not have complete geometric similarity with the prototype, is known as distorted model. 7. 7 Comparison of an Undistorted Model and the Prototype If the model is to be overall similar to the prototype, then all the three similarities (i. e, geometric, kinematic, dynamic ) should exist. But this is not possible in actual practice, as it is difficult to exist two types of similarities simultaneousl y.In general, and undistorted model of a prototype is made keeping in view the geometric similarity only and the remaining similarities are then compared for the scale ratio. 7. 8 Velocity of Water in Prototype for the Given Velocity of an Undistorted Model Consider an undistorted model geometrically similar to a proposed prototype like a weir, dam, spillway etc. Let h = head of water over the model v = velocity of water at a point in the model H,V = corresponding values for the prototype 1/s = scale ratio of the model to the prototype Velocity of water in the model v = Cv v2ghVelocity of water on the corresponding point in the prototype V = Cv v2gH C v 2 gh v = = V C v 2 gH h 1 = H s V = v vs Example 7. 3 The velocity at a point on a spillway model of a dam is 1. 3m/sec for a prototype of model ratio 1:10. What is the velocity at the corresponding point in the prototype? 64 Velocity in the model v = 1. 3 m/s Model ratio, 1/s = 1/10 s = 10 Velocity in the prototype V = v vs V =1. 3 x v10 = 4. 11 m/sec 65 References: 1. Hydraulics and Fluid Mechanics P. N. Modi and S. M. Seth 2. Hydraulics, Fluid Mechanics and Hydraulic Machines R. S. Khurmi 3. Fluid Mechanics Victor L. Streeter