Champion equality, diversity and inclusion Essay

1.1 Explain the models of practice that underpin equality, diversity and inclusion in own area of responsibility. Equality is to treat all as individuals; to respect race, disability, age, gender, religion, beliefs ,culture and sexual orientation. For all to be open to opportunities, to be treated fairly and respectfully, have rights and equal status in society and for all to reach their full potential. Diversity is to value that we are all unique and yet similar. We have different needs, interests, learning styles, language and personality etc. see more:identify examples of good practice in promoting equality and explain how and why they are effective Inclusion is to incorporate all of the above into our environment to participate in play and learning, to promote positive outcomes and the opportunity to grow and develop, to feel valued and empowered to succeed. Within the setting as a Director I come into contact with staff, visitors, parents, carers, children and other professionals on a daily basis. It is my responsibility whilst in contact with all these people and children that they feel that they’re treated respectfully and fairly As I am working in domiciliary care setting, my client group are people with mental and learning and people with physical disability. Both social and medical model have the implications on my client group. Service users are supported by care staff to promote their independence, to help them contact socialization with family, friends, and local communities, Care staffs are allocated to meet the cultural and social need of the service user to make a positive outcome in a person centered way. In case of any medical condition they seek medical intervention for the service users. 1.2 Analyze the potential effects of barriers to equality and inclusion in own area of responsibility There are many barriers to diversity and inclusion. The biggest ones are generally prejudice, culture and upbringing and religious beliefs. Prejudice is â€Å"a preconceived opinion that is not based on reason or personal  experience† those creating barriers to recognizing equality of rights for all. Cultural barriers can prevent, for example, consideration of spiritual, relational or dietary needs that do not conform with traditional expectations. Religious belief, where different religious beliefs are not taken into account and minorities are marginalized and not acknowledged. Other significant barriers could be structural, institutional and personal: Structural, where circumstances create or result in barriers People make the assumption about younger adult and consider all young people as a whole category rather than treating them as an individual. This type of stereotyping happens when people lack knowledge about equality and inclusion. The effects of barriers to employees are also high as they are excluded from their human right. Employer can easily discriminate those in terms of race, gender, sexual orientation and culture. 1.3 Analyze the impact of legislation and policy initiatives on the promotion of equality, diversity and inclusion in own area of responsibility My work place is committed to the promotion of equality, diversity and inclusion in policy and practice. It is committed in equal opportunity and also follows a common standard in respect of Race Relation (amendment) act 2000 in getting contract from council contractors. It also observes the code of practice of Commission for Racial Equality (CRE) in employment. Organization promote equality with respect to age, gender, race, disability religion , sexual orientation and establish a national common standard which is compliant to The Race Relation Act 1976 , as amended by The Race Relations (amended )act 2000. Under this law, organization carries out its function, it has due regard for the necessity to eliminate any unlawful discriminating and promote equal opportunity and harmonious race relation, it also follows the race relation code of practice for the elimination of racial discrimination and promote the equal opportunity in employment as approved by the parliament in 1983. It ensures that all employees and service users with or without disability, irrespective of background are treated equally and compliant to Disability discrimination act 1995. Under the sex discrimination act 1976, any staff  of service users has recourse and protection from any discrimination. Its policy is to protect the staff and service user from discrimination on the grounds of sexual orientation under The Employment Equality (Sexual Orientation) Regulations 2003. It ensures that men and women are same as per as pay is concern. Under Equal Pay Act 1970, organization’s policy is to make sure that man and women are treated equally and not discriminated in terms of their pay. To promote equality , diversity and inclusion in policy and practice , my work place also compliant to other legislation like, Human right act 1998, sex discrimination (gender reassignment) regulations 1999, Employment equality (religion belief) regulations 2003 , Disability discrimination amended act 2005, Equality act 2006, Racial and religious hatred act 2006. 2.1 promote equality, diversity and inclusion in policy and practice The organizations where I work promote equality, diversity and inclusion in both policy and practice. Staffs should regularly be reminded the importance of equality, diversity and inclusion in day to day practice. Staff should respect the choice, preference, ethnicity, origin, rights, and wishes of service users. Care staff should be allocated to service user to make sure that continuity of care is maintained. Staff would be selected against the service user in such a way which promotes the social and cultural need of service user. If possible, staff would be selected from same cultural and religious back ground and with same language spoken. Therefore care staff could appropriately relate to service user which ultimately lead to a positive person centered outcome. Care staff should promote independence, liaison with family members, friends, local community link for better social inclusion and to meet the wishes and choices of service users. Care staff would be aware of legislative impact while providing care in respect of religion, race age, disability, gender and sexuality. Race relation act 1976 and protection of harassment act 1997are in place to protect the vulnerable person. Disability discrimination act 2005 is also in place to protect person from discrimination because of disability. Sex discrimination act 1976 is to protect people from discrimination due to sexual orientation. Such other acts like, the Human Rights Act 1998 and Convention on the Rights  of the Child (UN, 1989) are in place to protect people from discrimination. 2.2 Challenge discrimination and exclusion in policy and practice The organizations where I work challenge discrimination and exclusion in both policy and practice. Staffs should regularly be reminded the importance of challenge discrimination and exclusion in day to day practice. In looking at this model I have found that many people have views that based on discrimination and prejudice they are embedded in today’s society, the attitudes and the surrounding environment often focuses on what a person lacks in terms of disability and focuses on condition or illness or a person’s lack of ability. To combat this prejudice within making space we use person centred care planning it is my responsibility to promote the use of this and to ensure that the support workers who deliver it are fully trained to do so. It is also vital that they have a good understanding of the model in order for them to work effectively with a service user. As a Director I am responsible for ensuring that the ethos within my team promotes equality and diversity every day, that the Support that is delivered within making space and any partnership working exercises good practice in this area this could be through training, policy and procedures, support plans, health files, as well as having a good understanding of equality & diversity. The staff are all expected to work in line with the Care Act, Mental Capacity Act 2005. Equality Act 2010, Human Rights Act 1998, 2.3 Provide others with information about: a) the effects of discrimination b) the impact of inclusion c) the value of diversity Effects include isolation, possible exclusion, demoralisation, marginalisation, situations where self-esteem, confidence and resilience  have the potential to be damaged. Forms of discrimination are gender, age, disability, sexuality, race, culture, religion ,poverty, education, personal features and English Is not first language. . In our care home we promote equal opportunity and we respect all the service users and their families. We help adults with language needs where English is not their first language which helps to ensure they can settle and adapt to our setting. Example (reading and singing in their language, books and talking with parents to find words we can use) Discrimination against anyone regardless of their needs can make them feel isolated and different to other. Very often adults with special needs have a very difficult time trying to fit in with other. Example: In our setting we promote inclusion and we treat everyone the same and explain to others â€Å"we are alike but different.† There are four areas of potential for the effect discrimination has †¢ Physical- Signs of poor health may manifest. self harming, attempting suicide, cutting, etc. Bullying might become physical and other types of abuse. †¢ Emotional – Emotional scars seem to run deep and are not healed easily. Could become to believe that persecutors are right, leading to a loss of self worth. Could lead to physical signs of trauma †¢ Social – lack of friends, social exclusion, no one to talk to about interests or plans for now and the future. Being treated as though someone doesn’t belong. Could lead to more emotional harm, physical harm, intellectual harm, etc. †¢ Intellectual – Not wanting to learn, withdrawing from places of learning. Not wanting to be around others unsafe behaviors Social inclusion in practice Promote and support access to social networks. Resolve transport issues so that they do not prevent people from participating in the wider community. Build links with community projects, community centres and schools to increase levels of social contact between  people from different generations. Identify, respect and use people’s skills, including the skills of older people gained in previous employment. Give people ordinary opportunities to participate in the wider community through person-centred care planning. Involve people in service planning and ensure ideas and suggestions are acted upon. We are promoting our service users to participate with the community by attending day centres, drama classes, arts and craft centres, keep in contact with friends and families.

Othello study question

There are three mall reasons for why Ago hates Othello. The first being that Ago deeply believes that there used to be an affair between his wife Email and Othello. While there is no actual evidence to support the affair, the fact that Ago believes it happened supports the fact that he is very paranoid and might be searching for reasons to hate Othello. The second is that Othello denied Ago a promotion he believes he very much deserved.The fact that Othello gives the promotion to Cassia is what leads Ago to take out revenge on both. The third (and most obvious reason to me) Is the simple fact that Othello Is a Moor (black) and Ago Is angry act the fact Othello has authority over him and is praised by the other characters. On line 1. 3. 322, Ago meant that we get to choose who we want to be and that whatever we nurture becomes our nature. Ago chose to warn Othello because he is two-faced and wants to remain on Othello side just long enough to take him down. . Line 1. 2. 60, spoken by Othello, means that neither Barbarian or Ordering had ever drawn there swords before. Othello is mocking them because they are both inexperienced and are pulling out shiny new swords against a great warrior. Act 2 1 . Ago (who we all know to be a sexist by now) Is very cynical towards females and views them all as meaningless. We can tell from way he treats his wife that he Is unappreciative of women. He Is also very critical and engrave towards all women, believing them to be nothing but deceptive.On line Ago describes women as being â€Å"pictures out of doors, bells in your parlors, wildcats in your kitchens, saints in your injuries, devils being offended, Players in your housewife, and housewives in your beds† (all deceptive and unfaithful creatures). . Shakespeare reveals Sago's true character through soliloquies because they give Ago a chance to actually be honest outside of his deceptive character in the main story.This is where the dramatic irony of the drama comes fr om. Sago's soliloquies also further the motif of the contrast between light and darkness (Ago revealing in his soliloquies the darkness of his heart matches the darkness of Othello skin, making them opposites Inside and out and how most of lagans evil plans are set Into motion at night, the physical representation of Sago's Inner personality). All of this

The Effects of Substrate Concentration, Reaction Time and Enzyme Concentration on Enzyme Reactions

The Effects of Substrate Concentration, Reaction Time and Enzyme Concentration on Enzyme Reactions Corey von Ellm-St. Croix Rachael Kwan ID#: 20427841 Matthew Hrycyshyn & Saeideh Mayanloo Biol 130L, Section 017 Wednesday, 9:30am-12:20pm, 151 November 09, 2011 A living system controls its activity through enzymes. Enzymes are made from hundreds or even thousands of amino acids connected in a very unique and specific order. Almost all enzymes are proteins, except for ribozymes. The chain of amino acids then folds into a unique shape. That shape not only allows the enzyme to carry out specific chemical reactions but to act as a very efficient catalyst. The enzyme speeds that reaction up tremendously. Each enzyme reacts with one specific reactant called a substrate that will form its products. The purpose of the experiments is to determine the effects of substrate concentration, reaction time and enzyme concentration on the direction of an enzyme reaction. Amylase is a digestive enzyme found in both the saliva and the small intestine. Salivary amylase is a hydrolytic reaction that breaks down starch molecules by systematically breaking off the maltose molecules from the ends of starch chains. The maltose is further broken down by another enzyme. Phosphorylase is an enzyme that systematically removes glucose molecules by consumes phosphoric acid to break the beta-1-4-glucosidic bonds in starch. The interaction of phosphate with the glucosidic bond results in the formation of glucose-1-phosphate and the loss of a chain unit in starch. In the reverse reaction the glucose part of glucose-1-phosphate is added as a new chain unit and phosphate is set free. This reversible enzymatic polymerization occurs with little change in free energy and therefor the reaction may choose to go either way. Iodine Test is a test for the presence of starch in which the sample turns blue-black in color when a few drops of potassium iodide solution are placed on the sample. A negative iodine test is when the reaction remains yellow in colour. It is the reaction between iodine and the coiled polymer of glucose known as amylase in starch that causes the colour change. The reaction occurs when straight amylase chains form helices in which the iodine can pass inside. Glycogen also receives a colour change because it is a glucose polymer as well but its structure differentiates from starch which therefore forms a brown colour change. The iodine test does not work for mono or disaccharides because they are too small to capture the iodine. The Benedict’s test is used to detect the presence of reducing sugars. Reducing sugars are sugars with a free aldehyde or ketone group. The free reactive carbonyl group allows all monosaccharides to be reducing sugars. The same goes for disaccharides as some also contain the free reactive carbonyl group. The colour of precipitate formed when the Benedict’s test acquires a positive result depends on the concentration of reducing sugars present. A green colour change indicates that few reducing sugars are present. Orange indicates a higher concentration, red an even higher concentration and brown is the highest concentration colour change. A negative test for reducing sugar occurs when the Benedict’s solution remains its blue colour. Materials and Method Materials and Method found in 1119 BIOL 130, Department of Biology 2011 Cell Biology Laboratory Manual. University of Waterloo, Waterloo. Fall 2011. p. 37-42. The procedure of the lab did not differ from that in the lab manual. Results Salivary Amylase Iodine test: Table 1 Test Tube Number| Results Through Experimentation| Control | 1 (10% salivary amylase solution) | Yellow | Negative | 2 (5% salivary amylase solution)| Yellow| Negative | 3 (2% salivary amylase solution)| Yelllow| Negative | 4 (1% salivary amylase soluti on)| Yellow| Negative| 5 (1% starch suspension)| Blue-Black| Positive| Table1: The table above represent the first iodine test done. Shows components of each test tube as well as the results and positive or negative control. Dilutions were done using tap water (may contain other molecules). Corresponds to steps 5 through 10. Benedict’s test: Table 2 Test Tube Number| Results Through Experimentation| Control| 1 (10% salivary amylase solution) | Brown-orange precipitate| Positive| 2 (5% salivary amylase solution)| Green precipitate | Positive| 3 (2% salivary amylase solution)| Blue | Negative| 4 (1% salivary amylase solution)| Blue| Negative| 5 (1% starch suspension)| Blue| Negative| Table 2: The table above represent the first Benedict’s test done. Shows components of each test tube as well as the results and positive or negative control. Each of the above test tubes contains 4ml Benedict’s solution and were boiled for 5 minutes when determining results and are related to steps 5 through 10. Iodine test: Table 3 Test Tubes| Number of Drops Till Negative| Time Interval| Time| 9+14 (1% salivary amylase solution)| 13 | 60 seconds| 13*60= 780 seconds| 8+13 (2% salivary amylase solution)| 12| 30 seconds| 12*30= 360 seconds| 7+12 (5% salivary amylase solution)| 10| 15 seconds| 10*15= 150 seconds| 6+11 (10% salivary amylase solution)| 18| 5 seconds| 18*5= 90 seconds | 10+15 (water)| (Always positive)| N/A| N/A| Table 3: The table above represents the time it took to reach endpoint. Shows components of each test tube, number of drops, time interval between drops and time to reach endpoint. Each of the above test tubes contains 2ml – 1% starch suspension and 2ml McIlvaine’s buffer. The above test tubes were placed in a warm bath at 37 degrees Celsius and pertain to steps 11-18. Benedict’s test: Table 4 Test tube| Results through experimentation| Control| 20 (water)| blue| negative| 9 (1% salivary amylase solution)| 1/3 brown -2/3 blue| Positive| 18 (2% salivary amylase solution)| 1/3 brown -2/3 blue| Positive| 17 (5% salivary amylase solution)| 1/3 brown -2/3 blue| Positive| 16(10% salivary amylase solution)| 1/3 brown -2/3 blue| Positive| Table 4: The table above represents the search for reducing sugars after endpoint. Each of the above test tubes contains 4ml Benedict’s solution and were boiled for 5 minutes when determining results and are related to steps 18-2 0. Phosphorylase Composition of test tubes: Table 5 TEST TUBE NUMBER | CONTAINS| One| 1. 5ml of 0. 01M glucose + 1 drop of 0. % starch suspension| Two| 1. 5 of 0. 01M glucose-1-phosphate+ 1 drop of 0. 2% starch suspension| Three| 1. 5 of 0. 01M glucose-1-phosphate| Four| 1. 5 of 0. 01M glucose-1-phosphate+ 1 drop of 0. 2% starch suspension| Five| 1. 5 of 0. 01M glucose-1-phosphate + 0. 5ml of 0. 2M potassium phosphate+ 1 drop of 0. 2% starch suspension| Six| 0. 5ml of 0. 2M potassium phosphate + 1. 5ml of 0. 2% starch suspension| Seven| 0. 5ml of 0. 2M potassium phosphate+ 1. 5ml of 0. 2% starch suspension| Eight| 4ml Boiled phosphorylase | Table 5: The above table represent the solutions present in the test tubes 1-8 from steps 2-10 Iodine test: Table 6 Test tube| Results through experimentation| Control| 1| Yellow | Negative | 2| Yellow| Negative| 3| Yellow| Negative| 4| Yellow| Negative| 5| Yellow| Negative| 6| Blue-black| Positive| 7| Blue-black| Positive | Table 6: Search for starch within test tubes 1-7. Shows components of each test tube as well as the results and positive or negative control. Composition of test tubes : Table 7 TEST TUBE NUMBER | CONTAINS| One| 1. 5ml of 0. 01M glucose + 1 drop of 0. 2% starch suspension + 2ml phosphorylase| Two| 1. 5 of 0. 01M glucose-1-phosphate+ 1 drop of 0. 2% starch suspension+ 2ml phosphorylase| Three| 1. of 0. 01M glucose-1-phosphate+ 2ml phosphorylase| Four| 1. 5 of 0. 01M glucose-1-phosphate+ 1 drop of 0. 2% starch suspension + 2ml boiled phosphorylase| Five| 1. 5 of 0. 01M glucose-1-phosphate + 0. 5ml of 0. 2M potassium phosphate+ 1 drop of 0. 2% starch suspension+ 2ml phosphorylase| Six| 0. 5ml of 0. 2M potassium phosphate + 1. 5ml of 0. 2% starch suspension+ 2ml phosphorylase| Sev en| 0. 5ml of 0. 2M potassium phosphate+ 1. 5ml of 0. 2% starch suspension + 2ml boiled phosphorylase| Table 7: The above table represent the solutions present in the test tubes 1-7 from steps 11-12 Iodine Test: Table 8 Time Interval| test tube 1| Test tube 2| Test tube 3| Test tube 4| Test tube 5| Test tube 6| Test tube 7| 10:28-10:32| yellow| Very faint blue-black| yellow| yellow| yellow| Faint blue-black| Blue black| 10:32-10:36| yellow| Blue black| yellow| yellow| yellow| Very faint blue-black| Blue black| 10:36-10:39| yellow| Blue black| yellow| yellow| yellow| Faint blue black| Blue black| 10:39-10:42| yellow| Blue black| yellow| yellow| yellow| Faint blue black| Blue black| 10:42-10:46| yellow| Blue black| yellow| yellow| yellow| Blue black| Blue black| 10:46-10:49| yellow| Blue black| Very faint blue black| yellow| yellow| Blue black| Blue black| 10:49-10:52| Yellow| Blue black| Faint blue black| Yellow| yellow| Blue black| Blue black| 10:52-10:55| Yellow| Blue black| Blue black| Yellow| Yellow| Blue black| Blue black| 10:55-10:58| Yellow| Blue black| Blue black| Yellow| Yellow| Blue black| Blue black| 10:58-10:42| yellow| Blue black| Blue black| yellow| Yellow| Blue black| Blue black| Table 8: Test for the presence and synthesis of starch. Contains the time interval from when the previous test had ended to termination of current test and the reaction result of test tubes 1-7. Figure1: above; represent the time it took each salivary amylase concentration to reach endpoint (when test for starch became negative. Discussion: Salivary Amylase The Iodine test’s control is the presence of starch. If starch is presence then the control is positive resulting in a blue-black colour change. The first iodine test or if you refer to table 1, gave a positive result for only test tube 5 which contained 1% starch suspension. Clearly starch is present based on just the component of the solution. A negative control in an iodine test will result in maintenance of the yellow colour of iodine. According to table one the test tubes containing 10% salivary amylase solution, 5% salivary amylase solution, 2% salivary amylase solution and 1% salivary amylase solution resulted in a negative control result. This is due to the fact that all that is present is the enzyme salivary amylase and water and therefore no starch. The Benedict’s test control is the presence of reducing sugars (sugars with a free aldehyde or ketone group). If a reducing sugar is present then a positive control reaction will occur. A positive control reaction is when a colour of the blue Benedict’s solution turns green, orange, red or brown after boiling. Each colour represents the concentration of reducing sugars present, green being the lowest and brown the highest. Referring back to table 2, test tubes 1 and 2 resulted in a positive control reaction. Even though test tubes 1 and 2 contained only salivary amylase the tap water used to dilute the amylase solution may contain some starch which would in turn become maltose a reducing sugar. The 10% salivary amylase (test tube 1) resulted in an orange colour change due to the fact that a higher enzyme concentration would more likely produce enough reducing sugars to result in an orange colour change. The 5 % salivary amylase (test tube 2) resulted in a green colour change which describes a low concentration of reducing sugars. This makes sense as a lower enzyme concentration would result in less reducing sugar being made through the enzymatic reaction between starch and amylase. A negative control reaction for the Benedict’s test occurs when the Benedict’s blue solution remains the same. Referring back to table 2 test tubes 3, 4 and 5 resulted in a negative control reaction. This may be due to the fact that the enzyme concentration were too low to produce enough reducing sugars from the starch found in the tap water to warrant a colour change. The starch (substrate) would for a substrate-enzyme complex with salivary amylase to produce maltose and salivary amylase. In conclusion enzyme concentration does play a factor in the speed of an enzymatic reaction. The results of Table 3, the second iodine test performed, is used to determine when the starch added with the different concentrations of salivary amylase has reached its endpoint and has been fully hydrolysed into maltose. The endpoint has been reached once the iodine test gives a negative control result which occurs once no starch or very few is present. According to the experimental data presented in table 3 enzyme concentrations again played a role in the speed of the reaction. 10% salivary amylase took 90 seconds where as 1% salivary amylase took 780 seconds. The starch (substrate) would for a substrate-enzyme complex with salivary amylase to produce maltose and salivary amylase. Test tube 10 + 15 will result in a positive control reaction all the time because it is comprised of water and starch. With no salivary amylase enzymes starch will always be present which is the positive control in an iodine test. A trend was found that as the salivary concentrations were halved the time to reach endpoint was doubled, leading me to believe an inverse proportionality to be present between enzyme concentration and time to reach end point. Table 4 was another Benedict’s test performed after the each combination of test tube had reached its endpoint. The positive result in a Benedict’s test occurs once a green, orange, red or brown colour change occurs because of the presence of reducing sugars. Test tubes 16-19, containing the different concentrations of salivary amylase, resulted in a positive control reaction because the starch (substrate) would for a substrate-enzyme complex with salivary amylase to produce maltose and salivary amylase and due to the fact that maltose is a reducing sugar which happens to be the control for a Benedict’s test, a positive control reaction will occur. The negative control reaction for a Benedict’s test is when the Benedict’s solution remains blue signifying the absence of reducing sugars. According to table 4, test tube 20 only contained water and the starch suspension with no amylase present a substrate-enzyme complex will not form which will not result in a reducing sugar. Phosphorylase Table 6 is another iodine test. The positive control reaction for an iodine test is when the solution turns blue-black. The experimental data given in table 6 shows that test tubes 6 and 7 gave a positive reaction for starch because of the 1. 5 ml of 0. 2% starch found in solution. The negative control reaction is when the solution remains the colour of iodine, yellow. Test tube 1 through 5 gave negative result because they either do not contain any starch in solution or the amount of starch present is too little (starch primer) and must be in presence of phosphorylase to synthesis a larger starch chain that can be reacted with the iodine test to provide a positive result. Table 8 is once again another iodine test. With the addition of phosphorylase some of the test tubes that gave a negative result in the previous iodine test (table 6) may now give a positive result because of the ability of the reaction between phosphoric acid and glucose to from glucose-1-phosphate and one less glucose unit in starch chain to go in either direction. Therefore a test tube with a starch primer may use the phosphorylase to synthesis into a starch chain. The same is for the solution that gave a positive reaction may turn negative in the presence of phosphorylase to form a starch primer and glucose-1-phosphate. Referring to table 8 the test tubes that resulted in a positive control reaction were 2,3,6 and 7. Because test tubes 6 and 7 were already gave positive results in previous iodine test (table 6) and did the same in this iodine test can only mean that a synthesis of a larger starch chain had occurred or the starch chain had not removed enough glucose bonds to result in a negative iodine control result. In test tube 7 the phosphorylase was boiled which would denature the enzyme so that it could not perform its task and therefore phosphorolysis could not take place and therefore test tube 7 would have to remain a positive control result. Test tubes 2 and 3 were primarily negative in previous iodine test but resulted in a positive control result when the enzyme phosphorylase was added. Table shows that over time both solutions grew more intense in colour signifying the synthesis of a longer starch chain. Test tube 2 had the starch primer and glucose-1-phosphate to start with and therefore took less time to give a positive control result. Test tube 3 did not contain the starch primer and I believe should not have given a positive control result. Test tube 3 did however contain the glucose-1-phosphate and perhaps may have started its own starch chain. This may have been done by having a glucose-1-phosphate and the glucose form a substrate-enzyme complex to give phosphoric acid and a larger glucose chain. The negative results were test tubes 1, 4 and 5 each contained the starch primer. Test tube 1 contained glucose but phosphorylase does not react with single glucose molecule and therefore test tube 1 will always give a negative control result. Test tube 4 used boiled phosphorylase and therefore the denatured enzyme would not be able to perform function which would result in an always negative control result. Test tube 5 had the right condition but perhaps never moved in one direction of the enzymatic reaction for too long resulting in a starch primer being present the whole time though it may have had potential to yield a positive control reaction. This shows that temperature do affect an enzyme. A buffer was also used in the reaction to allow for the proper pH levels to be obtained and therefore pH levels also affect enzymes. Overall throughout the experiment it was determined that substrate concentrations, reaction time and enzyme concentration effect the direction of an enzyme reaction. Reference Pelter, W. M. , McQuade, J. (2005). Brewing Science in the Chemistry Laboratory: A â€Å"Mashing† Investigation of Starch and Carbohydrates. Journal of Chemical Education, 82(12), 1811-1812. Ophardt, E. C. , (2003). Role of Enzymes in Biochemical Reactions. Virtual Chembook, Retrieved November 06, 2011, from Elmhurst College, http://www. elmhurst. edu/~chm/vchembook/570enzymes. html. Hall, I. (2008). Benedict's Test for Reducing Sugars. Retrieved November 06, 2011, from Ohio University, http://www. biosci. ohiou. edu/introbioslab/Bios170/170_2/benedict. htm

Legislative Action On Eyewitness Error And Wrongful Conviction Assignment

Legislative Action On Eyewitness Error And Wrongful Conviction - Assignment Example Ricardo Avilla, a neighbor whop lives across the street from the victims’ house testified in court that he saw the suspect run away from the house of the victims after hearing the gunshots. Avilla describes the suspect as a tall black man wearing a black coat and a grey cap. His description helped the police sketch the suspect’s picture. Another witness, Dan Christoffel, also –placed the suspect at the crime scene and gave a description of his physical appearance. A third witness, William also testified that he heard the suspect discuss how he murdered his victims. The appellant placed a doctor, Roy Malpass, on the stand to provide his opinion on the eye witness testimonies. Malpass was an expert on eyewitness identification, and his testimony was rejected by the jury who still found Tillman guilty. Kenneth Adams v. State†. This case involved a Kenneth L. Adams who, together with a Willie Rainge were convicted of murder, rape and aggravated kidnapping. Adams was sentenced to sixty years imprisonment for rape. He also got an additional seventy five years for each murder charge he was facing. The victims were Lawrence Lionberge and Carol Schmal. Carol, the victim is said to have gone to visit her boyfriend, Lawrence at his workplace. Carol is said to have been raped and shot here, and her boyfriend shot too. A witness later testifies to seeing the two defendants at the crime scene. Legislative action on eyewitness error and wrongful conviction. Undeniably, numerous cases have prompted judges to pass incorrect judgments on defendants due to the absence of adequate information. This is because of poor methods of collecting information and to some extent ignorance on the part of law enforcement officers. The involved parties in every case end up not being able to handle both the defendants as well as eyewitnesses based on the information they have attained (Wise, Dauphinais & Safer, 2007). To eliminate eyewitness errors, legal system ought to adopt the most effective method meant to extract the required information. This will ensure the convicted serve just sentences. In addition, it will ensure the entire process observes the involved parties’ rights, which the law dictates despite their role pertaining to the case. Therefore, this entails utilizing proficient officers to interrogate eyewitness and not excluding the service of eyewitness experts, for inst ance, psychologists (Tillman v. State, 2011). However, psychologists ought to be proficient in their field to the extent of being able to proffer the required information based on reliable scientific background and pertinent to the case supposed to undergo litigation process (Tillman v. State, 2011). In my opinion, the best solution or approach in eliminating numerous eyewitness errors that characterize litigation process is by employing tripartite solution (Wise, Dauphinais & Safer, 2007). In this solution, the initial step entails considering eyewitness’ testimony during the litigation process, which is also supported in the Tillman v. State case (Tillman v. State, 2011). Since, this enables the jury and those arbitrating cases to understand essential facts that may be difficult especially in the field judges are not conversant with, for instance, psychology (Martire & Kemp, 2009). This is evident in Tillman v. State’s case, though Dr. Malpass failed to present clear and convincing facts intended to prove the testimony, he claimed to have a strong scientific base. (Tillman v. State, 2011). Therefore, to ensure reliability of any information by eyewitness expert, the proponent ought to prove his or her (1) expertise employed is legitimate, (2) testimony lies within the required scope and (3) uses the field’

FIN 352 (1) Essay Example | Topics and Well Written Essays - 500 words

FIN 352 (1) - Essay Example One of the major OBS activities is the issuance of guarantees. This may be called by a bank to take place at a future time, and the dedication to lend at a forthcoming time if the borrower wishes. This may prompt the result of a contingent risk which may be out of the control of the financial institution. A duration of a zero-coupon bond is a bond that does not pay any interest in its maturity life. That is; its maturity is equivalent to maturity because hundred percent of its present value is made by the payment of the nominal value at maturity (Lee & Alice 316). The relationship that exists between duration and maturity in bonds is that the longer a bond takes to mature, the greater is its duration or volatility. Duration changes each time a bond makes a coupon installment. After some time, it abbreviates as the bond nears maturity. Elsewhere, the relationship between duration and yield is that the higher a bond yields as it nears maturity, the lesser is its duration. This is because the present value of the inaccessible cash flows gets to be dominated by the value of the closer installments. Also, the relationship between duration and interest rates is that the higher a coupon bond is, the more interest it generates and vice versa. The financial significance of duration is the mea sure of a bond’s correspondence to the interest changes in the economy. Value at risk is method used to quantify and measure the level of financial related vulnerability inside an association over a determined duration. Its approach to the market risk is based on measuring three variables that are the level of potential risk, the probability amount of the specified level of risk and the time frame. Value at risk is closely related with the normal distribution. It measures portfolio risk along the normal distribution curve. The curve was developed by Carl Friedrich Gauss hence the name

Diane Meyers' Feminist Perspectives on the Self, Essay

Diane Meyers' Feminist Perspectives on the Self, - Essay Example This continues to perpetuate the idea that females are somehow secondary. This has led many women to lose or never develop a sense of self identity and autonomy. Modern feminists, like Diane Meyers, feel that in order for woman to gain a proper identity, sense of self and true equality it will require complete reforming or completely inventing new philosophies with the intention of elevating not diminishing woman. History There is a distinct difference between sex and gender. Biologically speaking, sex refers to the genetic determination, sex organs, and levels of hormones. However gender is something different. People’s gender identities are not always in agreement with their sex organs; as in the case of the transgendered, for example (Gender spectrum).Western philosophy prefers to see the world in a far more black and white, hence male and female kind of world. Much of U.S. perspectives are guided by Christian ideologies that are renowned for elevating the value of men and diminishing and limiting the place of woman. Gender in modern society is a matter of learned behaviors and indoctrination to behave appropriately for their sex. This is reflected daily in the purchasing of pink clothing, baby dolls, and toy sewing machines for girls, while boys receive blue clothing, dump trucks, and play weapons. From the day you are born to the day you die social structures and gender traditions will dictate who we are and who we become based, primarily, on whether we are male or female (Dietert, and Dentice 121). Discussion Once we are ingrained with the ideas of our gender identity taught to us by others, anything that varies from that may seem wrong, freakish, and makes changing quite difficult. She identifies women can never gain a sense of self identity or autonomy in modern society as long as society is working with the principles founded on male dominant ideologies. She believes existing society is far to andocentric, or male dominant, it by nature demeans females as secondary and it works continually perpetuate make dominance and control (Meyers). For example, a recent cases involving courts giving dirty cops a free pass and refusing to prosecute and officer accused of rape. Men protecting men from accountability in the crimes against women is the truest example of male dominance. (Bennetts ) In order for woman to gain a sense of self identity, autonomy, and true equality is to restructure outdated, male dominated, and offensive concepts it will be necessary to rethink the activities of motherhood, developing ethics of care, exploring separatist practices, and re-conceptualization of the definition of autonomy. Motherhood has always been perceived by the male dominated society as actions that were biological imperatives and instinct. However, in the modern era mothers like Susan Smith and Casey Anthony are not at all women that are naturally meant to be or are capable of being good mothers. In other words, being a good mother is a mo ral and ethical choice that women make, which means they are capable of thinking, being moral, and ethical people. Women have been referred to as somehow morally inferior to men because they are not capable of applying morality, logic, or wisdom due to their very emotional tendencies. This, also, reflects back to Christian ideologies, Eve disobeyed God and tricked Adam into eating the apple and apparently every female,

Organizational Human Resources Assignment Example | Topics and Well Written Essays - 1500 words

Organizational Human Resources - Assignment Example However an overall organizational diagnosis must be conducted to identify the needs and the areas of change. Organizational change can be defined as the initiative by the mangers to keep a constant creative, innovative and intelligent watch over the environmental forces and to audit the impact and influence on the business concerned and to find out action programs to find out appropriate strategies to maintain balance between the two different forces, controllable as well as non-controllable. The study has been conducted in lieu of analyzing the key areas of changes, dealing with the factors providing resistance to changes and the process of overcoming the changes. The study has been conducted by keeping Diamond Express, Inc and the organizational scenario of the company in mind (Goswami, 2010, p. 105). Background of the Study Diamond Express, Inc. is a two years old customer sales and service company. It has 150 employees. Very recently the senior management has hired a new HR manag er to develop a fully functional human resource department. This is a key strategic move considering the near future expansion plans of the company. Identifying Areas of Change The HR functions of the organization is scattered among individuals. This consists of some employees belonging to the administrative position looking after paper works and a management team looking after HR issues. Considering the mentioned landscape of the organization the key challenges of the newly appointed HR manager has been summed up. One of the major challenges to be faced by the manager is to achieve centralization. HR functioning is a very much core and specialized area. Therefore the company must have a fully functional HR department to look after the core areas. Therefore the manager may hire some HR executives to look after the core areas such as recruitment, payroll processing, performance management, etc. Also these executives act as a touch point to various departments. The employees looking a fter the admin work can also be a part of the HR department forming HR and admin division. This recommendation has been provided based on the assumption that the organization has the budget to afford recruitment new executives. Another challenge to be faced by the new HR manager is to keep a high morale among the employees. The hiring of a new manager may make some the employees to raise a few eye brows. This may lead to negative organizational grape vines lowering the moral of the employees. This may create insecurity among the employees and lead to attrition. Therefore the best way to avoid such unwanted circumstances is to communicate properly with the employees to build an environment of trust and employee engagement to ensure retention. As the management as well as the HR manager wants to achieve organizational change it is imperative for the employees to understand the role and responsibilities. Therefore the Hr manager must make sure that detailed Job descriptions are prepare d across the all departments. The HR manager should entrust the responsibility to the executives looking after different departments. The executive should carry out a job interview for specific job holders to prepare a detailed and appropriate job description. Along with job description the employees should be provided the KRA or key result areas, so that the employees can understand the parameters

Library Worksheets Essay Example | Topics and Well Written Essays - 750 words

Library Worksheets - Essay Example On this link, I found a number of search feedbacks. From the different options provided, I chose the link and then typed the word globalization. From the search I was able to get the needed information based on the topic of discussion. Reich (5) defines globalization in the text as the tendency to transform the economic and political aspects to match the international standards. I would not use this source for various reasons. One reason why the source is not viable is that it was written in 1998 and globalization is a dynamic concept and the various definitions can be changed based on the prevailing circumstances taking place in the international system. Consequently, the definition is not clear as othe3r concepts are used to explain globalization ensuring sustained confusion in the meaning. In fact, the source as established and the inherent definition may not validate the concept of globalization in the modern dispensation. The Google search is a very effective tool for looking up information. Immediately I keyed in the information, I managed to get the information I needed in an instant. However, the searches bring about a number numerous information that can otherwise confuse someone though somebody with a stable mind and focus can easily spot the information needed. The article provides a broad perspective over which a number of issues can be painted in so far as the concept of globalization is concerned. The information is precise and current to the components that define the concept of globalization. The search used for this part of the exercise was the articles and journals that are found online. The information in the articles is well researched on and precise to a larger extent. Most of the information is current and well referenced. The source defines the concept of globalization in varied and different ways. Globalization in the

Term Paper Essay Example | Topics and Well Written Essays - 1250 words - 2

Term Paper - Essay Example It has its focus on the target readers who may or may not be very much interested in each and every detail of the study but can be very much interested in knowing how to maintain their weight not to regain. The article has been a successful effort in providing what readers look for in any news. The article used for this study is ‘A Self-Regulation Program for Maintenance of Weight Loss’ from the journal ‘New England Journal of Medicine’ published on 31 October 2006. The team of Dr. Rena Wing, PhD have conducted this study. Dr. Wing is also Brown University professor of psychiatry and human behaviour and co founder of National Weight Control Registry program. The paper is based on one of the most concerning issues of today’s scenario. Obesity is a problem which leads to several other health related and psychological problem in an individual. People once lose weight sometimes become relaxed and regain the weight they had lost. The journal article is based on this issue of obesity and maintenance of weight loss. The main issue in the study are regaining of weight in individuals after weight loss program and impact of maintenance program based on self regulatory theory on this weight regains. People face to face interaction and daily weighing c reates better impact on the interest and efforts of maintaining weight and avoiding weight regain. The hypothesis of the paper is that â€Å"the interventions, delivered face to face or over the Internet, would decrease average weight regain and reduce the proportion of participants who regained 2.3 kg or more during a period of 18 months.† The study is about weight regain. There are various dependent and independent variables considered in this study. There were various dependent variables like weight loss in specific period, calories intake, physical activity and method of instruction like face to face, internet or control group were dependent on variables like sex, age, weight,

Risk Of Malathion Essay Example | Topics and Well Written Essays - 1000 words

Risk Of Malathion - Essay Example Nevertheless if medication is dispensed hurriedly Malathion has no long-standing disturbances; whilst low level revelation has few or even no health troubles. In view of the fact that Malathion appears to be an insecticide it requires to be scattered during early evening to trim down the harm causes for the animals, as well as for the other insects. Malathion exists as a chemical broadly used to act toward mosquito invasions. Even as being valuable in manipulating mosquitoes, there are countless dangers to think about when employing this chemical. As said by the Agency for Toxic Substances and Disease Registry (ATDSR), revelation to malathion by means of the air, food, and water could possibly cause several difficulties like how the brain as well as the nervous system functions. In examination, it shows that exceedingly high doses of malathion could cut organ operations (Wilson, 2003). If an individual whom has unintentionally or deliberately gulped down malathion, he/she should dig up for treatment hurriedly. Even as there has been no evidence that malathion instigates cancer, examinations have found amplified occurrences of some cancers in human beings who are frequently exposed to malathion they are farmers as well as the chemical applicators. Dose-response. The EPA made a list of the careful amounts of the Malathion insecticide would strictly be 0.1 milligrams of Malathion for each liter of drinking water, 0.1 to 135 PPM intended for specific varieties of food, as well 15 milligrams for each meter of work section by an 8 hour operation day designed for a 40 hour labor week. Exposures towards a degree fewer than these quantities might possibly be a reason for skin irritation, infuriate asthmatic patients, or function as a lung irritant. However, in giving out high dosages of Malathion could surely cause complexity in breathing, tightness of chest, etc., and possibly death (EPA, p 149). Exposure. The risk of giving out the Malathion insecticide for mosquito management in the core of the municipality at the low down concentrations connecting with mosquito spraying should be kept to a smallest amount by giving sufficient announcements to the community also by spraying for the mosquitoes at early evening. Even if malathion stops working in a count of hours, it could collapse into more lethal composites than malathion itself. Once exposed to sunlight it could bring about a chemical reaction, which consecutively increases the arrangement of trimethyl contaminations, which appears to be highly-poisonous. An individual who is exposed towards high doses of Malathion is as well at a higher danger than those who is exposed towards lower doses. An investigation in Florida illustrates the consequences of low-doses of malathion on unborn kids. Children who were born to pregnant ladies that were exposed towards this chemical enclose higher degrees of learning disabilities (United States. Environmental Protection Agency, 1993). Malathion Not as Safe as Believed - 5 Die - 2,800 Poisoned.SOURCE: Archives in Toxicology, 42:95-106, 1979. The following fact is derived from the document from the Bureau of Tropical Diseases, Center for Disease Control, Atlanta, Georgia called "The Toxicological Properties of Impurities in

The Renovation of English Vocabulary from Old English to Modern Research Paper

The Renovation of English Vocabulary from Old English to Modern English - Research Paper Example In the transformation of English language from Old English to Modern English, crucial changes have taken place in vocabulary, spelling, and pronunciation which is illustrated by an analysis of these elements in ‘Canterbury Tales’ compared with Modern English equivalents. In the Text 81 from the ‘Canterbury Tales’ one finds several examples of the origins of the vocabulary and a comparison of the original Old English vocabulary and their Modern English equivalents proves how the vocabulary developed overages. The Friar’s Prologue in ‘Canterbury Tales’, for example, opens with the lines: â€Å"This worthy lymytour, this noble free, / He made always a manner louring chiere / Upon the somonour, but for honesty / No vileyns word as yet to him speak he.† (Freeborn) This can be read in the Modern English as follows: â€Å"This worthy limiter, this noble friar, / He turned always a lowering face, and dire, / Upon the summoner, but for cou rtesy / No rude and insolent word as yet spoke he.† (Freeborn) The changes or the developments in each of these items can be easily recognised by the readers and this progress in the vocabulary of the language reflects the general nature of English language which has developed over several periods. In conclusion, the history of English language establishes that the language progressed from Old English to Middle English to Early Modern English and the vocabulary is a major area of language in which variations are more readily noticeable over long stretches of time.

Reading Important Essay Example for Free

Reading Important Essay 1. Reading is fundamental to function in todays society. There are many adults who cannot read well enough to understand the instructions on a medicine bottle. That is a scary thought especially for their children. Filling out applications becomes impossible without help. Reading road or warning signs is difficult. Even following a map becomes a chore. 2. Reading is a vital skill in finding a good job. 3. Reading develops the mind. 4. Reading is how we discover new things. 5. Reading develops the imagination. 6. Reading develops the creative side of people. 7. Reading is key in developing a good self image. Non-readers or poor readers often have low opinions of themselves and their abilities. 8. Good reading skills improve spelling. 9. Ideas written down have changed the destiny of men and nations. 10. The power of written ideas communicated through reading is a foundational reason why some governments oppose free and honest communication. Illiterate people are easier to control and manipulate. They cannot do their own research and thinking. They must rely on what they are told. Words are the building blocks of life. You are, right now, the result of words that you have heard or read and believed. What you become in the future will depend on the words you believe about yourself now. People, families, relationships, and even nations are built from words. Think about it. Why is Writing Important? It seems like a silly question, but it is very important to be able to express yourself well. Our writings precede us, or introduce us. For example, when we apply for a job or to enroll in a school, we need to submit a resume and sometimes a cover letter, or when sending e-mails to someone we don’t actually know well or haven’t met yet (work partners, customers, or even responding on behalf of the company you work for). If we make a bad (or illegible) impression, the outcome for us may not be favorable. Poor writing may cost a lot; it may lead to misunderstanding and misconstruing due to sentence structure, grammar, punctuation, and spelling problems. We need to write well for the following reasons: To translate, communicate, and materialize our ideas and thoughts into accessible documents that are useful to ourselves and others To report our work in informative, concise, and professional formats Another important reason is that when writing, we are sending a message to our readers about who we are. Therefore, we need to be clear, focused, and accurate so as not to be misunderstood, underestimated, or ignored.

Power generation

Power generation Introduction The availability of electricity and its per capita consumption is often regarded as an index of national standard of living in the present day civilization. The amount of power generated is a sign of growing gross national products which reflects prosperity of the people. Energy goes in tandem with progress. The lack of it and inadequate measure can throttle the entire economic activity and well being of the country. Therefore, energy is considered as the most basic input for any country for keeping the wheels of its economy moving. Electricity is an easy form of energy which can be produced easily, transported easily, can be used easily and also controlled easily. Power plants are used to produce electricity in bulk quantities. However, in a developing country like India, the demand for power is increasing at a very rapid rate. As a result the use of renewable forms of energy is being increased and at the same time actions are being taken to improve the overall efficiency of the existing power plants. Combined cycle power plant couples a steam and a gas power plant in order to improve the overall efficiency to 70%. This combined cycle recovers much of the exhaust energy and uses it further to drive a steam or gas turbine or a district heating plant. As a result, there is an increase in the power produced and at the same time it reduces additional cost and the generating cost. There are many other benefits of a combined cycle power plants. Benefits like high efficiency and low environment impact are the most important. In todays world, emission levels of all kinds of fuels must meet stringent regulations acceptable to the countrys government. It is therefore important for power producers to invest in plants which have low emissions level. Risk mitigation and public acceptance are paramount. Combined cycle plants especially those which use natural gas or other renewable resources are a good choice for low emissions. Carbon dioxide emissions and other gases produced in a combined cycle power plant are much lower than other fossil fuel technologies. Power Generation System Simple Power Plant Cycle A simple power plant generation cycle utilizes only a single thermodynamic cycle at a time. It converts the energy stored in fossil fuels into shaft work and ultimately into electricity. It uses water which is generally in the liquid state and sometimes even in the vapor state, as the working medium. The energy which is released by the burning the fuel is used to heat water and convert it to steam which is then further used to run a turbine to generate electricity. The steam which leaves the turbine is sent to a condenser such that the water can be re used. However, the efficiency of a simple cycle is still less and large amount of exhaust is emitted at the end of the cycle. The efficiency of a simple power plant is given by: ÃŽ ®(cycle) =W(net)/Q(1)=W(T)-W(P)/Q(1)=Q(1)-Q(2)/Q(1) =1-Q (2)/Q (1) The major components of a simple power plant cycle are as follows: (i). Compressor (ii). Combustor (iii). Power turbine (iv). Generator In a simple power plant as seen, ambient air is filtered and then compressed to a pressure of 14 to 30 bar (190 to 420 psig). As the air is compressed its pressure increases which in turn are used to burn the fuel producing hot gases with a temperature generally higher than 1,000 degree Celsius. This then expands in a turbine driving the compressor and generator. The expanded hot gases leave the turbine at ambient pressure and at a temperature between 450 to 650 degree Celsius depending on the turbine efficiency, pressure ratio, and turbine inlet temperature. Such a power plant has 35% efficiency only. Gas Compressor It is a mechanical device which is used for increasing the pressure of a gas by decreasing its volume. Generally air is used in a power plant for compression, however, oxygen, nitrogen and other gases are also compressed. There are three general types of compressors, namely, positive displacement, axial and centrifugal. Positive displacement compressors may be reciprocating piston type, in which the gas is taken in during the suction stroke of the piston, and is compressed by decreasing the volume of the gas by moving the piston in the opposite direction. Centrifugal compressors use high speed impeller to increase the energy of the gas which is then converted into pressure in the diffuser. They are used to compress large volume of gas to moderate pressures. In Axial compressors gas is made to flow parallel to the axis of rotation of the rotor which in turn contains a number of rows of blades. As the gas passes through the blades its energy increases which is converted into pressure. This type of compressor is used for jet aircraft engines and gas turbines. Combustor It is a part of turbine where the combustion takes place. In a gas turbine, air enters the first combustion chamber after the compressor. Here, fuel is mixed with the compressed air and the exhaust is then used to drive the turbine to obtain work. A combustor should fulfill the four basic conditions: (i). Supply enough air for complete combustion of air. (ii). Secure enough turbulence for thorough mixing of fuel and air. (iii). Maintain a furnace temperature high enough to ignite the incoming fuel air mixture. (iv). Provide a furnace volume large enough to allow time for combustion to be completed. It is important to determine the right amount of oxygen that should enter the combustor. Amounts of Carbon-di-oxide and oxygen are indicators of excess air. If the amount of oxygen is more in the combustor than the required amount, it will burn fuel more rapidly and the efficiency would reduce. A combustor has three main components, namely, the outer casing which is the high pressure container, the combustion chamber, and the fuel injection system. [1][4] Turbine A steam turbine is a prime mover which continuously converts the energy of high-pressure, high temperature steam supplied by a steam generator into shaft work with the low temperature steam exhausted to a condenser. This energy conversion essentially occurs in two steps: (i). The high pressure, high temperature steam first expands in nozzles and comes out at high velocity. (ii). The high velocity jets of steam coming out of the nozzles, impinge on the blades mounted on a wheel, get deflected by an angle and suffer a loss of momentum which is absorbed by the rotating wheel in producing torque. A steam turbine is basically an assemblage of nozzles and blades. The fig of a Turbine is given below. Many types of turbines are used in Power Plants, namely: 1. Steam turbines are used for electricity generation in thermal power plants, i.e. plants using coal and fuel. 2. Gas turbines are also called turbine engines. Every turbine is provided with an emergency control lever which can immediately shut down the running of turbines in case a catastrophy occurs. Each power plant has a fixed turbine rotation rate. These rates at which the turbines rotate are different for different process. In a power plant the turbines fail to operate if: 1. Shaft speed exceeds 3300 rpm 2. The lubrication system fails 3. Turbine balancing is not proper 4. Temperature of plant increases 5. Cooling mechanisms not working properly Control And Supervisory Instruments: Many control and supervisory instruments are provided for the safe and effective operation of a turbine. They are as follows: 1. Pressure gauges are used to monitor the pressure of main steam at various valves. 2. Thermometers are used to record temperatures at every valve and in the combustor valve. 3. A Speed recorder is used to monitor the turbine rpm all the time and in case its speed increases beyond a set value then it is deactivated. 4. Watt meters and voltmeters are used to determine the steam and heat rates at various points in the process. 5. A trip control lever is provided in case of an emergency. Generator It is a device that converts mechanical energy into electrical energy. A steam generator generates steam at the desired pressure and temperature by burning fuel in its furnace. A generator forces electric charges to be in motion through an exterior electrical circuit, but it does not create electricity or charge, which is already present in the wire of its windings. As it can be seen from Fig 4, heat is produced in a generator because of losses caused by current flow in the stator and field windings. This affects the temperature in the generator. By using cooling mechanisms such an event can be avoided. Generators are usually cooled using hydrogen at very high pressures say at 3 bars. Hydrogen is used since its specific heat is the highest and its molecular weight is the least. Combined Cycle Power Generation The Carnot efficiency is the efficiency of an ideal thermal process. Generally the efficiencies of some processes are less since there are a large amount of losses involved. Thus, a distinction between energetic and exergetic losses is drawn. Energetic losses are mainly losses incurred due to heat, and are thus the energy lost in the process. Exergetic losses are internal losses caused by irreversible processes in accordance with the second law of thermodynamics. The process efficiency can be improved by raising the maximum temperature in the cycle, releasing the waste water at a lower temperature or by improving the process to minimize the internal exergetic losses. The interest in combined cycles arises particularly from these considerations. Although, no single cycle can make all the improvements. It thus seems reasonable to combine two cycles to one. Supplementary firing may raise the exhaust temperature to around 900 degree Celsius. Also, high gas temperature raises the condition of steam which in turn improves the efficiency of a power plant. The two thermodynamic cycles generally used in a combined cycle power generation are Brayton cycle and Rankine cycle. Brayton Cycle In Brayton cycle the air is first compressed and then at constant pressure reversibly heat is added to it. Due to this, expansion of air takes place in the turbine. This leads to emission of hot gases at a constant pressure which helps in bringing it to the initial state. The Brayton cycle consists of 4 cycles in total, out of which two are reversibly isentropic and the other two are reversible adiabatic. Also a Brayton cycle is called as the air standard cycle for the gas turbine power plant. [1] Cycle Processes: A. 1-2 Isentropic Compression (q = 0) B. 2-3 Isobaric Heat Addition (w = 0) C. 3-4 Isentropic Expansion (q = 0) D. 4-1 Isobaric Heat Rejection (w = 0) Rankine Cycle We can use a hypothetical value for every process in the vapor power cycle which represents its basic intended operation and something which does not produce any extraneous effect. From the steam boiler, it is used as a constant pressure heating process to convert water to form steam, for the turbine as an ideal reversible adiabatic expansion of steam, for the condenser it is a reversible constant pressure heat rejection as the steam condenses till it becomes saturated liquid, and for the pump, the ideal process is the reversible adiabatic compression of this liquid ending at the initial pressure. When all these four processes are ideal, the cycle is called a Rankine cycle. There are four basic steps in a Rankine cycle: Step1-2: working fluid is pumped to high pressure from its initially low pressure state. This process requires low energy. Step2-3: the high pressure working fluid then enters a boiler where it is heated continuously such that it becomes dry saturated vapour. Step 3-4: the dry saturated vapour is then used to turn the blades of a turbine to generate power. The temperature and pressure of the working fluid decreases. Step 4-1: the wet vapour then enters a condenser where it is condensed to become a saturated liquid. District Heating A district heating system uses hot water to bring heat to towns and communities rather than using electrical power. This technology is quite old. The oldest district heating system which is still in operation was used to warm a French village from geothermal hot springs in the fourteenth century. Later on, US were the first country to use the process of district heating in plants. A steam district heating system has been in use by the US Naval Academy since 1852. The first commercial system began in Denver in as early as 1880. As of today, nearly 30,000 district heating plants are working in the US and there are a thousand more around the world. A district heating plant contains insulated pipes which carry hot water from the plant to various sites. Also these pipes are interconnected between various buildings through a junction point as can be seen from Fig 7. From these junction points, hot water is taken from the mains to a heat exchanger which is also called a heat sub-station and present inside each building. Because of this the heating circuit which is present inside each building can be isolated from the main heating system. A temperature sensor is present on the heat substation which monitors the temperature of water at all times. Also a meter is attached, which calculates the amount of water consumed by each apartment or building and are charged accordingly. To ensure safe and smooth running of the plant, human intervention is reduced by running the plant automatically. Advantages Of Combined Cycle Power generation The worldwide demand for combined cycle power plants is growing dramatically because of its large advantages, namely: (i). High overall plant efficiency: up to 70% can be obtained. (ii). Low investment costs: up to 30% lower than that required for a conventional steam power plant. (iii). Small amount of water required: amount of cooling water required is only about 40 to 50% as much as for a steam plant. (iv). Great operating flexibility: the simple steam cycle makes it possible to start up and shut down the plants quickly which also affects the efficiency. (v). Phased installation: because the gas turbines can go into operation much sooner than the steam plant, installation in stages is possible. The gas turbine can keep on generating power as the steam plant is under construction. This makes it possible to adjust the growth in demand for energy in a grid. (vi). Simplicity of operation: combined power plants are fully automatic and are suitable for operating where the operating staff is less experienced. (vii). Low environmental impact: because of their low emission levels and high efficiency, such plants are suitable for use in a heavily populated region. [1][5] Components Of A Combined Cycle Power Plant The major components of a combined cycle power plant are listed below: i. Fuel: Different types of fuel may be used, namely, natural gas, coal, oil, petrol, diesel or any other conventional source of energy. Generally, natural gas is used as primary fuel. Also, experiments are being conducted to use renewable sources of energy like solar energy, wind energy, geothermal energy, nuclear energy etc as the main source of fuel. Using renewable source if energy would decrease the cost of running the plant tremendously and increase the efficiency as well. [2] ii. HRSG (Heat Recovery Steam Generator): HRSG is a heat exchanger. It is the link between the gas turbine and the steam turbine process. It is used to recover heat from a hot gas stream. It produces steam that can be used in a process. HRSG are commonly used in a combined-cycle power station, in which the exhaust is fed to the HRSG to generate steam which in-turn drives a steam turbine.There are three main types of HRSGs, namely: 1. HRSG without supplementary firing. 2. HRSG with supplementary firing. 3. Steam generators with maximum supplementary firing. HRSG without supplementary firing are the most common. Its main function is to convert the exhaust energy of gas turbine into steam. [2] iii. Deaerator: the main function of a Deaerator is to remove air and other dissolved gases from the water or steam in gas/steam cycle. This is necessary as the high oxygen content present in the steam/water corrodes the components of a plant along with the pipes. Generally, oxygen content of more than 7 to 10 parts per billion(ppb) is highly dangerous. Deaeration should be done continually since small leakages of air at air flanges and pump seals in the part of the cycle vacuum cannot be avoided. The solubility of the gases increase at a higher temperature and low pressure. A Deaerator removes these gases by heating the feed water to the saturation temperature. This feed water then passes through a heat exchanger after which it is sprayed from the top. By coming in contact dissolved oxygen and carbon di oxide get released. The Deaerator is usually kept in between the feed water system such that the total pressure difference between the boiler and the condenser is shared equally betw een the condenser pump and the boiler feed pump. The Deaerator is not used water cooled nuclear power plants as there is a danger of radioactive substance release. There are two types of Deaerators: a. Tray type Deaerator b. Spray type Deaerator iv. Control System: In todays world almost all cycles are automated in order to improve the efficiency and at the same time reducing human intervention. Control system is to a power plant what a brain is for a human body. Supervision, control, performing operations in a safe and reliable environment, continuously checking for leakages and faults is all done by the Control System. For this reason, the control and automation systems of a combined cycle power plant form a relatively complex system even though the thermal process is fairly simple. Fully electronic control systems are employed in todays modern combined cycle plants. The main features of the control system for a combined cycle power plants are: 1. Truly distributed architecture 2. Complete range of functions for process control 3. Communication capability due to several bus levels 4. Compliance with standard communication protocol 5. Openness for third party applications 6. On-line programmability with easy creation/editing of the programs v. Cooling system: An engine that is not cooled will soon reach a temperature which will seriously harm its functioning. If the heat is too intense it can cause the lubricant to burn up, leading to souring of cylinders, burning of pistons and bearings or any of variety of other mechanical troubles. Especially in a power plant where combustion of fuel continuously takes place for power generation, excess heat is like an enemy which needs to remove as soon as it is generated, least it would be dangerous. Two types of cooling systems are used, Air cooling and Liquid cooling. vi. Cogeneration: It is the simultaneous generation of electricity and useful heat. It is basically a recycling process. In conventional power plants, the waste heat is released into the atmosphere. Cogeneration captures this heat and re uses it for industrial heating purposes. In processes like district heating temperatures up to 130Â °C can be reached. Manhattan is the biggest steam district in the world. Many European countries also make use of this technology. Using cogeneration a bottoming plant captures the byproduct heat for domestic and industrial purposes thus increasing the overall efficiency of a plant. Paper and textile mills, chemical factories, sugar factories etc are few of the many industries which use saturated steam as the desired temperature for many purposes like heating and drying. For constant heating or drying steam is used. Also, the industry also needs power to drive its various machines. For this purpose combined cycle plants which use cogeneration are used since it serves both the purposes. District Heating Through Cogeneration Cogeneration involves the production of both electricity and thermal energy simultaneously from a common fuel source. The rejected or exhaust heat is used here for the process of district heating. Other applications included Desalination cooling. District heating is the latest technology for heating of homes and buildings in cold places like Europe. Heat which is produced in the thermal section in form of hot water is transported to houses and other areas using insulated pipes, such that the temperature doesnt change and a separate boiler is not needed at the receiving end. Vapor Absorption System A vapor absorption system can be used in the process of district heating. This system uses Ammonia which has a relative lower boiling point than water. Thus, less heat is needed to heat the water. Later ammonia can be removed from the water-ammonia mixture and reused again. The flow chart for such a system is as follows: Advantages Of District Heating There are many advantages of using this technology. A few of them are as follows: 1. Heat is transported to the urban areas using a heat exchanger which has a longer life. 2. Water is the main carrier. It can be easily procured from sea (desalination) or underground water. 3. Heating equipment takes less space and can be easily installed. 4. It can be used all year along without ant breaks. 5. Efficiency is more. 6. Distribution system is controlled using Computer which automatically increases or decreases the amount of water being delivered, depending upon the needs. Operation Of A Combined Cycle Power Plant Usually a combined cycle power plants are operated automatically. There are switches available which make it possible to activate the starting or shutting down of the equipment from a central control room. The commands may be given by operating staff or from a high level starting program which runs automatically. The start and stop are decided on several parameters which are pre defined in the program. Because the plants have a shorter start up time and an even quicker load change capability, the combined cycle power plants are often called to be dynamic in its behaviour. It is also quick in reacting, thus it is capable of following up quick changes. [2][6] Modern CCPP in the 50-400 MW range can be started within the following times: For a combined cycle power plant, Start up procedure is divided into three stages: 1. HRSG purging 2. Speeding up and synchronization of Gas turbine 3. Speeding up and synchronization of Steam turbine Purging of the boilers is a very important process. It prevents any explosion from unburned hydrocarbons by running the gas turbine at a high ignition speed of about more than 30% of normal speed, which helps in blowing of air through the HRSG. Purging then depends on the volume of gas left behind in the gas turbine. After the purging has been done, the gas turbines run at nominal speed, synchronized and loaded to the desired level. [7] Programmable Logic Controller Plc Definition A programmable Logic Controller, which is generally called as PLC, is a state of the art, digital industrial computer. A programmable logic controller is an industrial computer in which control devices such as limit switches, push buttons, temperature sensors or pressure sensors provide incoming control signals into the unit. An incoming control signal is called an Input. Incoming control signals interact with instructions specified in the user ladder program, which tells the PLC how to react to the incoming signals. The user program also directs the PLC on how to control the field devices like starter lights. A signal going out of the PLC to control a field device is called an Output. [5] Advantages Of Plc The main advantages of using PLC in the field are as follows: (i). Gain complete control of the manufacturing process (ii). Achieve consistency in automation (iii). Improve quality and accuracy (iv). Work in difficult hazardous condition (v). Shorten time to market (vi). Lower the cost of quality, scrap and rework (vii). Offer greater product variety (viii). Control inventory[5] How Does PLC Work Microprocessor is the main working brain of all the computers. The computers microprocessor, which is technically known as the central processing unit (CPU), supervises many controls and instructions as defined by the user. The microprocessor responds to the input signals and follows the instruction that it has been programmed to do. When the PLC is running and is following the programmers instructions it is called as solving the user problem. PLCs follow the instructions that are stored inside their memory. Also they may store programs for future use. Each instruction that has been entered will be placed inside the memory in the increasing order. These lists of instructions are called as a Ladder diagram. A basic PLC and its components are shown below. The instructions that are required to be carried out are transferred to the memory of the controller using a computer. The ladder diagram is made by the user using various kinds of latches, timers, counters and other accessories available with the software. After the ladder diagram has been verified and corrected, we download the program into the processors memory. Downloading basically means transferring the program from a personal computers memory to the logic controllers memory. Before downloading a user program, the processor must be in the program mode. After downloading the entire program all the wires have to be connected properly unless the required outputs would not be shown. Also, one can download the program as many number of times as it may be required. The continual running of the program in the PLC is useful in continuously determining if any input is being changed by the user or not. This process is called scanning. According to the commands given and the kind of timers or counters used, the output would be shown which is basically turning of the output light, which is present on the right hand side of the controller. A PLC interfaced with a computer is shown below. The PLC has come a long way since the first time it was used for industry applications. In these years, the PLCs usage has been increased drastically. It has been designed to withstand the harsh temperature. Since mostly PLCs are employed in industries where the temperature is usually on a higher side, they have been made resistant to heat. It is for this reason it is called as industrially hardened device. Also PLCs are small and easy to store. Also they require minimum of space. Also PLC gives the user the ability to try new things. The PLC can easily be programmed for any number of times. The programs are developed from the ladder diagrams. As an industrial computer, the PLC can easily replace functions of timers or counters. Also any type of sequence can be tried on the software. Also these days functions like arithmetic and data manipulation or shift registers have been made available along with the software which has increased its range of operation. The main benefit of using PLC is easy troubleshooting. In industries ladder diagrams may span for many pages. As a result it becomes very difficult to identify the errors. However, PLC software comes with an inbuilt troubleshooting device which tells the user where errors have occurred, if any. This helps in easy identifying of the problem and saves precious time. PLC, thus, is a very important tool in industry usage. RS LOGIX 500 RSLogix is a used to run a particular or a full segment in an industry. RSLogix is a product of Allen-Bradley, which provide the best industry controllers. This software offers unbeatable productivity and is widely used in industries. A simpler version called RSLogix 500 was made by Allen-Bradley for laboratory purposes. I have used this software for interfacing different cycles in a combined cycle power plant. RSLogix 500 offers [5]: (i). Flexible easy to use editors (ii). Diagnostics (iii). Troubleshooting tools (iv). Time saving features and functionality Simulation On Rs Logix 500 The project was divided into three parts: 1. Brayton Cycle 2. Rankine Cycle 3. District Heating Ladder diagrams for each were constructed after thoroughly understanding each process in detail. Use of timers, counters and switches were made in the ladder diagrams to illustrate limit switches. Temperature and pressure values have been assumed and are not based on actual standards. RSLogix 500 provides with a large variety of instruction palettes, like normally open closed switches, timers, counters etc. Values of temperature and pressure sensors were assumed and are not based on factual data. Also, various kinds of up-counters and down-counters along with many types of timers were used in designing of the ladder diagrams. I started with designing of ladder diagram for Brayton cycle. Then I designed a Rankine cycle which uses the waste of Brayton cycle as the input and lastly I designed a District Heating plant which uses the wasteful outputs of both Brayton and Rankine cycles. A Combined Cycle Power Plant increases the efficiency of a power plant by almost double. As a result, its usage is increasing globally as more and more simple plants are being converted to combined cycle power plants. Given below is the figure of an instruction palette as seen in the software. After the Ladder logic is entered, the whole file or project is verified without errors and is given access for download. The figure for the same is given below: Brayton Cycle The ladder diagram is as shown below. It has a lower efficiency than a steam cycle. The above figure shows the ladder diagram for the Brayton Cycle. The first rung illustrates the fuel which is supplied. I have taken Natural gas as the main source of fuel and Diesel for emergencies. The fuel mixes with Air. The ratio of fuel: air is about 1:30. A timer which acts like a pressure sensor is attached in parallel with the compressor. Since this timer is attached to a done bit, it cuts off the fuel and air supply after 15 seconds. This is so done since it is assumed that after, say 15 seconds, the pressure in the compressor reaches 200 Bar. If the compressor is opened for more time, then the compressor might blow off because of extreme pressure. This pressure I have assumed is totally hypothetical and varies with the type of material used in the making of the compressor. After the air and fuel gets compressed i.e. the pressure increases and the volume decreases (according to Boyles law), then the compressor valve opens. The compressor mixture then enters a combustor wher e the combustion takes place. I have attached a up-counter in parallel with the combustor. The up-counter does the same function

Low Pressure Mercury Vapour Electronic Discharge

Low Pressure Mercury Vapour Electronic Discharge A common discharge lighting luminary for use in an office environment would typically be a low-pressure mercury-vapour electronic discharge (fluorescent) lamp. The lamp is constructed from a hollow glass tube with an aluminium cap at each end. Within the tube are two electrode coils, one at either end. The inner surface of the glass tube is coated in phosphor, and the tube, containing a small amount of mercury vapour, is filled at low pressure with an inert gas such as argon or krypton. Construction of a typical fluorescent lamp http://www.lamptech.co.uk/Documents/FL%20Introduction.htm Block diagram showing fluorescent lamp and associated circuitry http://www.leonardo-energy.org/drupal/files/root/Images/ballast/Grundschaltung_e.GIF An automatic starting switch (starter) is used to initialise the flow of electrons from a coated filament cathode, which then collide with mercury vapour atoms, exciting their electrons to a higher energy state. This higher energy state is unstable and returns to a lower, more stable level, and in so doing produces a very small amount of blue-green light and a large amount of ultraviolet radiation. When the UV radiation comes into contact with the phosphor coating it causes the phosphors electrons to reach a higher energy state, which when returning to a normal level give off visible light; the colour of which is dependant upon the chemical composition of the phosphor. Fluorescent lamps are negative resistance devices, meaning that as the current increases, the electrical resistance decreases, allowing further increase in current flow. If the rise in current flow were to be uncontrolled the lamp would quickly self-destruct. To prevent this, a ballast device is used in order to regulate the current flow. Fluorescent lamps are a well established standard for general lighting in industrial, commercial and domestic applications. They come in a range of standardised sizes, power ratings, white colours, and colour temperatures. Other benefits of using fluorescent lamps compared to, for example, incandescent lamps, is that they are more energy efficient and have a longer life, typically 10 20 times longer than an incandescent lamp. When switched on they illuminate almost immediately, there is no waiting period whilst they warm up to their operating temperature, which for a fluorescent lamp is room temperature. When switched off, they can be restarted immediately, unlike high pressure sodium lamps which must cool down. One disadvantage of fluorescent lamps is that in some circumstances they may flicker at twice the supply frequency, causing a stroboscopic effect which, in a workshop type environment, may cause rotating machinery to appear stationary. One way to overcome this is by using lamps with a high-frequency electronic ballast. A common discharge lighting luminary for use in an indoor sports environment would typically be a high-intensity discharge (HID) type lamp, such as metal halide or high pressure sodium. High Pressure Sodium Sodium vapour at high pressure and temperature is highly reactive with glass, which would rapidly fail as a result. So, for a high pressure sodium lamp, a ceramic arc tube body, known as translucent polycrystalline alumina (PCA) and manufactured from aluminium oxide, is used instead; and is itself enclosed by a protective outer glass bulb, which is either evacuated or contains an inert gas. High pressure sodium lamp (image from: http://www.hydroyard.com/) The arc tube is evacuated of air and volatile contaminants, a dose of sodium-mercury amalgam and a filling gas of either argon or xenon are introduced. The type of gas filling is chosen for its ability to allow an arc to strike at low pressure. Tungsten electrodes, having a coating of electron-emissive material, connect to the electrical supply and the tube is hermetically sealed. A high voltage pulse causes the gas within the arc tube to ionise, creating an arc between the two tungsten electrodes, and increases the temperature of the gas. Initially, the arc voltage, due to the low vapour pressures, is low. As the amalgam temperature increases so does the pressure, and thereby the voltage, taking a few minutes for the lamp to reach its optimum operating condition. Once the lamp has been switched off, it needs to cool for a short while before being able to restart. The ballast, as with the fluorescent tube, controls the current to ensure stable operation. Diagram showing basic construction of a high pressure sodium lamp http://en.wikipedia.org/wiki/File:High_pressure_sodium_lamp.svg Some of the benefits of using high pressure sodium lamps in an indoor sports environment are that they give good colour rendering which is important where teams need to clearly identify each other by their colours. HPS lamps also provide a whiter light which allows players to clearly identify the sports equipment, especially where that equipment is used in fast moving sports such as the ball in a game of squash. Task 20 Escape Route Lighting It is essential that every workplace has a means of egress during an emergency, and this requires a system of emergency lighting be fitted to ensure that evacuation can be done in a safe manner should the normal lighting system fail. BS EN 50172:2004/ BS 5266-8:2004 details the requirements for emergency lighting systems. Legislation requires that lighting be sited in points of emphasis along the exit route, covering areas such as each exit door, intersections, changes of direction and floor level along the route, stairways, fire fighting equipment, alarm points, potential hazards, emergency escape signs, first aid points, equipment and machinery that requires shutting down in an emergency, outside and near to each final exit. The term near is defined as within 2 metres, measured horizontally. Examples of points of emphasis At each exit door At each piece of fire fighting equipment and alarm call point At each intersection of corridors Near each first aid post The escape route must attain a minimum level of illuminance, additionally, every compartment on the escape route must have at least two luminaires in order to provide some light should one fail. BS 5266 Pt 7: 1999 (EN1838) details the Light Level Requirements, a minimum of 1 lux anywhere on the centre line of the escape route for normal risks. A uniformity ratio of 40:1 maximum to minimum must not be exceeded. This illuminance must be provided for the full duration and life of the system. 50% of the illuminance must be available within 5 seconds and the full value within 60 seconds of supply failure. (http://www.cooper-ls.com/dg_emersystem.html) High Risk Task Area Lighting Guidance for the requirements of provision of emergency lighting in high risk areas is given in BS 5266 Part 10: 2008. The provision of emergency lighting in High Risk Task Areas must be sufficient enough to allow the safe shutting down of machinery and equipment in areas such as workshops, control and plant rooms, switchgear rooms, production lines, laboratories, or any other areas where potentially dangerous situations or processes are likely to occur, and which might affect the safety of the workforce or other occupants. It is a requirement that for high risk areas the maintained illuminance should be not less than 10% of the normal maintained illuminance on the reference plane for the task, and not less than 15 lux, whichever is higher. It should have a maximum uniformity ratio of 10:1, and a response time of at least 0.5 seconds. It should also be free from stroboscopic effects. http://www.voltexlighting.co.za/Download/emergency_lighting.pdf, http://www.westyorksfire.gov.uk/departments/fireSafety/nfgs/FS-NFG029-EmergencyLighting.pdf Most emergency lighting systems fall into three types, Maintained, Non-maintained and Sustained. A maintained system is one where the luminaire uses the same lamp for both standard and emergency use, can be switched on or off in the same manner as a normal light, but once the regular power supply is lost the lamp will illuminate, using its back-up battery pack. A maintained system has an M designation and a number indicating the emergency duration in hours, e.g. M2. A non-maintained system is one that illuminates only when the mains supply fails. It is designated NM and, again, is followed by a number that indicates its duration of illumination. A sustained system is a combination of the maintained and non-maintained systems, and contains two (or more) lamps within a luminaire. Each lamp is supplied independently, one by the mains supply and the other by the battery back-up for when the mains supply fails. This system is designated S and also has a number indicating the emergency duration. Maintained systems should generally be used in locations such as pubs and bars and other premises where alcohol is served, along with public areas where the lighting levels can be reduced to below the levels required for escape route illumination. Sustained systems can be considered for places that may require safe lighting at all times, e.g. hallways and stairwells in areas of accommodation such as hotels or halls of residence, where evacuation at night may be necessary, even if no power supply failure has occurred. As an energy and lamp-life saving measure it may only be necessary to have the lamps illuminate during night time, or other periods of low ambient light, activated by a motion sensor during normal operation, and automatically in emergency. Non-maintained systems can generally be considered for all other situations. A duration of emergency illumination lasting between 1 and 3 hours can be considered sufficient for most situations. BS 5266 gives detailed guidance regarding which category may be most suitable for a given situation and location. Back-up power supply Providing a source of power in the event of a mains supply failure can be done by one of two main methods; either by battery or generator. There are two distinct types of battery systems, a self-contained system whereby each luminaire contains a battery, charger, and changeover device; and a central system where these items are located in one room and which supply all the luminaires in the system. Using the latter method, it is essential that the wiring be of a high standard as there may be a risk of loss of power due to fire damage, and also poor performance due to voltage drop over long cable runs. Therefore, the former may be preferable to overcome these drawbacks; installation is simpler and requires little maintenance other than routine testing. Where a back-up generator is used, it should be either run at all times or be able to start automatically and run up to provide the required output level in 5 seconds or fewer. Where neither of these conditions can be met, it should be s upplemented by a battery back-up system, that is capable of running the emergency lighting system for one hour. In this situation the generator need not be required to start automatically, but be available to take over from the battery back-up as soon as possible. Signage Cooper Lighting and Safety states that illumination requirements for signage must conform to the colours of ISO 3864, which defines that exit and first aid signs must be white with green as the contrast colour. The ratio of luminance of the white colour to the green colour must be between 5:1 and 15:1. The minimum luminance of any 10mm patch area on the sign must be greater than 2cd/m ² and the ratio of maximum to minimum luminance shall be less than 10:1 for either colour. (http://www.cooper-ls.com/dg_emersystem.html) Example of emergency exit sign conforming to ISO 3864 http://img.archiexpo.com/images_ae/photo-g/emergency-exit-signs-143363.jpg Task 3 Number of luminaires required The luminaires require an electrical input of 58 watts and suffer losses of 18%, which result in a power rating of 41 watts. Taking into account a correcting factor for this power rating of 1.04, multiplied by the Utilisation Factorà ¢Ã¢â€š ¬Ã‚ ¦ à ¢Ã¢â€š ¬Ã‚ ¦the number of luminaires required is 50.28; rounding down to 50 to give a common sense workable number. Taking a space/height ratio of 1.7, and the height of the luminaire above the working plane being 3.2 metres, the space between luminaires should be a maximum of 5.22 metres. Arranging 50 luminaires to best fit a room of dimensions 20m x 15m gives an arrangement of 5 luminaires by 10 luminaires, with the length of each luminaire orientated across the width of the room. The spacing between each luminaire across the width of the room would be 1.5 m with 0.7m between the luminaire and the wall at each end. The space between the centre of each luminaire down the length of the room would be 2m with 1m between the centre of the luminaire and the wall at each end. Both of these figures fall well within the maximum spacing determined by the space/height ratio. Although to be mathematically accurate in determining the minimum number of luminaires required, one would usually round up; real world considerations need to be taken into account such as arranging the luminaires to fit the rooms dimensions, and the additional costs involved in adding substantially more luminaires required just to make a nice aesthetic pattern. In the question, no consideration has been given to the availability of natural light, nor the range of commercially available lamps and luminaires which could be more efficient and effective than the given figures suggest. Diagram showing orientation and spacing of luminaires 15 metres 1.0m 1.5m 0.75m 2m 1.5m 20 m