Monday, September 30, 2019
Hamlets Tragic Flaw
Procrastination is an action or rather an inaction, because when you procrastinate, you are avoiding completing a task. ââ¬Å"Emotionally, Hamletââ¬â¢s procrastination produces in him a growing rage that leads to his killing of Polonius (3. 4) â⬠¦. Set in motion the incidents that lead to the bloody climaxâ⬠(Boyce). This quote illustrates the topic of the following essay. It clearly outlines why the inability to act is ultimately the tragic flaw of the character Hamlet. Firstly, Hamletââ¬â¢s procrastination ultimately leads to the premature death of many characters throughout the play.In act 3 scene 4, while confronting his mother, Hamlet hears a noise from behind a curtain. Thinking it was Claudius spying, Hamlet passes his sword through the curtain and stabs Polonius. Polonius calls out ââ¬Å"O, I am slain! â⬠(3. 4. 22), then falls and dies. Hamlets Procrastination led to this because his emotions are being built up so, that when he hears the slightest thing that may be Claudius, he reacts in a violent way. That is not a good thing, because the death of Polonius will lead to two other events that will eventually cause three other characters to die.Moreover, in the final scene, three more characters die. Claudius has a cup of poisoned wine for Hamlet, but Gertrude unknowingly drinks it and immediately starts to die. Just before she passes, she exclaims ââ¬Å"No! No! The drink, the drink ââ¬â O my dear Hamlet ââ¬â the drink, the drink! I am poisnââ¬â¢d (dies)â⬠(5. 2. 299-300). After Gertrude dies, Hamlet and Laertes fight more violently, and Laertes cuts Hamlet. In a brawl, Hamlet gets a hold of Laertesââ¬â¢ sword and stabs him. When Hamlet realizes the sword is poisoned, he turns and stabs Claudius.Hamlet says ââ¬Å"â⬠¦the point envenomed tooâ⬠¦ (stabs the king)â⬠¦ Follow my mother! (Claudius dies)â⬠(5. 2. 311-317). After Claudius dies, Laertes says to Hamlet ââ¬Å"â⬠¦he is justly servedâ⬠¦Ã¢â¬ (5. 2. 318-322) then dies. He says this to reassure Hamlet that he did the right thing. Hamletââ¬â¢s procrastination led to the climax of the play, because if he would have killed Claudius sooner, he would have discovered that Hamlet knows about the murder and he never would have called the sword fight, and none of this brutality would have occurred.Secondly, Hamletââ¬â¢s procrastination is causing other characters to plot against him. After Hamlet killed Polonius, Claudius plans to ship Hamlet away to England and make Poloniusââ¬â¢ death look accidental. When he reveals his plan, he is talking to Gertrude and says ââ¬Å"O Gertrude, come away! / The sun no sooner shall the mountains touch, / But we will ship him hence: and this vile deed / We must with all our majesty and skill, / Both countenance and excuse! â⬠(4. 1. 28-32). He is simply telling Gertrude that Hamlet will be on a ship to England before the sun rises.He also adds that they must both ââ¬Å"co untenance and excuseâ⬠the death of Polonius to protect their identity. Furthermore, when Laertes hears of his fatherââ¬â¢s death, he returns to Denmark, and he and Claudius plan to kill Hamlet and make it look like an accident. The king devises a plan and tells Laertes ââ¬Å"to thine own peaceâ⬠¦ he shall not choose but fallâ⬠¦ even his motherâ⬠¦ shall call it accidentâ⬠(4. 7. 61-68). Laertes is not fully satisfied with the kings plan and he says to Claudius ââ¬Å"My Lord, I will be ruled; / The rather if you devise it so / That I might be the organâ⬠(4. 7. 69-70).Laertes and Claudius devise a plan in which Laertes will kill Hamlet to avenge his fatherââ¬â¢s death, and Claudius will not need to worry about Hamlet revealing the truth of King Hamletââ¬â¢s murder. Lastly, Hamletââ¬â¢s procrastination allows time for events to unfold, ultimately bringing about his own death. Claudius caught on that Hamlet knows what happened to his father, so Claudius has Hamlet fight Laertes in a fencing match. We find out about this plan when a lord comes to invite Hamlet to the match. The lord entered the room where Hamlet was and said ââ¬Å"My Lord, his majestyâ⬠¦ if your / Pleasure hold to play with Laertesâ⬠(5. . 186-190). Hamlet accepts the invitation to the match. The purpose of the fencing match is for Laertes to get revenge on Hamlet for killing Polonius. This will also serve as a means for Claudius to eliminate Hamlet so that he will not reveal the truth about King Hamletââ¬â¢s murder. Furthermore, unbeknownst to Hamlet, the match is rigged. When Claudius tells Laertes that he is to kill Hamlet in the fencing match, Laertes responds ââ¬Å"I will doââ¬â¢tâ⬠¦ I will anoint my sword. / I bought an unction of a mountebank, so mortalâ⬠¦ if I gall him slightly, / It may be deathâ⬠(4. 7. 140-148).He says this because he wants to inform the reader that he will poison his sword to ensure Hamlet dies if h e cuts him even slightly. This shows how determined Laertes is to get revenge on Hamlet for killing Polonius. Therefore, the tragic flaw of Hamlet is ultimately procrastination. There are many examples throughout the play supporting this fact. If the other characters would have procrastinated the way Hamlet did, the play would have been much heavier with subplots and underlying moods and feelings. Based on this play, most people would think twice before putting off any large tasks that they may need to accomplish.
Sunday, September 29, 2019
Harlequin Enterprise Mira Decision
Harlequin enterprise had a competitive advantage in the womenââ¬â¢s romance fiction genre up until the 1980ââ¬â¢s and early 1990ââ¬â¢s. Harlequin faced steady loss of share in a growing women's fiction market due to the popularity of single title novels. It is costly to imitate but to stay competitive I would recommend that Harlequin perform a limited launch of Mira by re-developing titles in their back-list and generating direct-to-reader sales through the Book Club, while it explores global distribution and marketing relationships. The Mira decision is great way of gaining new grounds but there are numerous issues surrounding it. First, competitions are fierce and there is great deal of threat to its potential in the U. S market. The agreement with Simon and Schuster at the end of romance wars may not be sustainable. If harlequin launches Mira in direct competition with S&S it would be very difficult considering harlequin is dependent on S&S for the distribution of its series titles within the U. S market. If Mira is pursued, harlequin would have to redevelop its distribution chain and its value chain within U. S. Harlequinââ¬â¢s brand loyalty is strong due to its readership base. This is evidenced by the direct-to-reader Book Club, which currently provides 3/8 of US Sales at significantly higher margins than indirect sales. With this value, harlequin should proceed cautiously but look towards reducing external threats and external opportunities. The Mira decision could be the solution to increase sales. With harlequinââ¬â¢s reputation of producing high quality books, Mira could be successful. Thereââ¬â¢s a great deal of risk involved in this investment, with significantly higher cost for production, distribution and marketing and considering harlequinââ¬â¢s inadequate expertise outside of the romance realm. As with the 1987 worldwide case, I believe harlequin could learn from their mistakes and be optimistic towards their future.
Saturday, September 28, 2019
Analysis of the Case Oticon Using the Political Metaphor Essay Sample
1. IntroductionThe metaphors of organisations and direction have been discussed by Gareth Morgan in his book ââ¬Å"Images of Organizationsâ⬠( Morgan. 2006 ) . Morgan exposed eight metaphorical images of organisations including machine. being. encephalon. civilization. political system. psychic prison. flux and transmutation. and instrument of domination. Each one of these metaphors creates insight. but besides obscures some corners. They have both pros and cons. They enable seeing. but besides non seeing. No 1 of them is said to be right and right. 2. BackgroundChattanooga Ice Cream Division is one of three major incorporated industries to CFC. Chattanooga Food Corporation. The division lost third-largest client for no logical grounds. Charles Moore. the president and general director of the division conducted a direction meeting to discourse current state of affairss. look into the root causes. and happen out proper solutions. Many struggles occurred during the meeting. The actions and reactions can be projected to reflect how the division maps as one of metaphorical images. In this study. the instance is analyzed utilizing the political system metaphor. In other words. it discusses what we could see and reflect when projecting the divisionââ¬â¢s behaviour on the rules and attacks of the political system metaphor. 3. TheoryAn organizationââ¬â¢s political relations is most clearly manifest in the struggles and power dramas that sometimes occupy halfway phase. and in the infinite interpersonal machinations that provide recreations in the flow of organisational activity. More basically. nevertheless. political relations occurs on an on-going footing. frequently in a manner that is unseeable to all but those straight involved ( Bacharach A ; Lawler. 2000 ) . There are three relationships to be considered when speech production of organisations the systems of political activities. which are involvements. struggle and power ( Morgan. 2006 ) . Politics accepts the world of multilateralism. Therefore. the construct of political relations is strongly connected with the diverseness of involvements. Projecting that on organisations by and large. they could be regarded as spheres for accommodating different involvements ( Culbert A ; McDonough. 1980 ) . Different involvements are natural and must be handled. For that intent. the general involvements are analyzed as single involvements. There are three types of single involvements including undertaking. calling. and extramural involvements. Undertaking involvements are connected with the work one time has to execute. while calling involvements are connected to what the individual want to accomplish with the work. The extramural involvements are connected what we want to accomplish as a private selfââ¬â¢s. There is a structural diverseness of involvements in organisations. That could be bounded by two extremes along hierarchal graduated tables. where bureaucratsââ¬â¢ inclination represents the upper portion. and professionalsââ¬â¢ inclination dominates the lower broad countries ( Benson. 1973 ) . When involvements collide. struggles arise. The political position admits the presence of struggles. There are three major signifiers of struggles including. struggles between individual. groups/departments. and value systems/structures ( Brown. 1983 ) . There are five chief attacks for struggle declaration. including avoiding. viing. suiting. compromising and collaborating manners ( Burrell A ; Morgan. 1979 ) . Power is the medium through which struggles are resolved ( Bacharach A ; Lawler. 1980 ) . There are two relevant positions of power signifiers including resources and societal relation or dependence. Furthermore. there are 14 beginnings of power. That may affect formal authorization ; control of scarce resources ; usage of organisational construction. regulations. and ordinances ; control of determination procedures ; control of cognition and information ; control of boundaries ; ability to get by with uncertainness ; control of engineering ; interpersonal confederations. webs. and control of informal organisation ; control of counterorganizations ; symbolism the direction of significance ; gender and the direction gender dealingss ; structural factors that define the phases of action ; and the power one already has ( Morgan. 2006 ) . 4. Analysis4. 1. InterestsWhen looking through the instance of Chattanooga Ice Cream Division. many manifestations and contemplation could be analyzed from the political system metaphor position. One of the worlds that political relations accept is that all political systems embrace different involvements ( Culbert A ; McDonough. 1980 ) . The meeting Moore conducted reflects this world every bit good. As we noticed. many frailty presidents of the divisionââ¬â¢s sections tried to depict and analyse the job the division experienced in a manner that made their sections out of lending causes. For case. Billy Fale. the frailty president of production. tried to justify his section by explicating their immense attempt to acquire stock lists manageable despite the limited efficiency the divisionââ¬â¢s information systems had. Whereas. Stephanie Krane. the divisionââ¬â¢s accountant. blamed the complexness of the information systems that required long clip to develop. trial. and put in. Furthermore. for forcing herself off of the causation factors. Krane explained her experience to retrieve old problems. The other frailty presidents manipulated the description of the state of affairs so that the possible solutions go in their departmentsââ¬â¢ favours or involvements so to talk. Barry Walkins. the frailty president of selling. attributed the job to the disregard of his recommendations. He asked sing mixed-ins in the divisionââ¬â¢s production program. establishing that on his selling research. He might be seen as a director who wanted to enter a triumph for his manner of thought. researches. or departmental sphere. Another contemplation could be built on the reaction of Les Holly. the divisionââ¬â¢s gross revenues director. He tried to drive the sentiments judgmentally. Holly started reflect the root causes of the job from the sense that the remainder of directors didnââ¬â¢t have the broad image he had. since he used to pass most of the clip in the shops. He focused on operational lacks. such as stockouts and back orders. to do it rational to counterbalance that with the promotional allowances. irrespective any other conducive factors. Moore has accepted the difference of involvements of the directors. This is evident from the manner he dealt with their sentiments. He considered all solutions in malice of his familiarity to the background of motivations for each director. The single involvements could be classified into undertaking involvement. calling involvements. and extramural involvements ( Culbert A ; McDonough. 1980 ) . Fale showed his involvements of maintaining everything under control by rejecting the alteration Walkins proposed. All his reactions during the meeting seemed to be operational and numerical contemplations. That sort of involvements could be seen as undertaking involvements. The same is to be said for Krane. Her remarks reflect her involvement of lodging to certainty and non doing mistakes. On the other manus. Hollyââ¬â¢s involvements may be classified as calling involvements. as he emphasized on the promotional allowances many times. Possibly. he wanted to better his external personal relationships utilizing such allotments. In the same context. we think that Walkinââ¬â¢s involvements could be classified as extram ural involvements. since he wanted to turn out his endowment of marketing research practically. His proposal was rational and strongly relevant to the job. He tried to demo his trueness through his honest efforts to do the division changes positively. This manner of categorization doesnââ¬â¢t needfully mean that this categorization is an absolute affair. All of them may hold overlapped involvements that belong to each class. ConflictsAnother common facet of the political system is struggles. Conflict will ever be present every bit long as the involvements collide. That may include struggles between individuals. sections. and constructions ( Coser. 1956 ) . In Chattanooga. the struggle arose between Fale and Walkins were more personal. Walkins criticized Faleââ¬â¢s disregard to his suggestion. and Fale in bend criticized Walkinsââ¬â¢ thoughts. Both reviews were directed to the personal behavior. Additionally. Holly criticized the policy concerned with cost decrease at the disbursal of gross revenues section. The struggle arose between him and Krane could be seen as departmental struggle. There are five common manners of struggle declaration including avoiding. via media. competition. adjustment. and coaction ( Burrell A ; Morgan. 1979 ) . For Chattanooga. and before the age of Charlie Moore. his male parent led the show wholly. He was the first responsible for about everything. while Charlie wanted to travel the division toward the collaborative manner. During the meeting. he gave manner for everybody to demo their contemplations. But they were still unfamiliar with this sort of communicating. When struggles arose. Moore played the function of moderator. which was doing certain that everybody would show about their ideas and sentiments reasonably. However. he kept the concluding determination to himself. We find the behavior Moore showed in struggle declaration is more like the adjustment manner. PowerPower is a really important histrion in the political systems. It is the medium through which struggles are resolved. There are 14 beginnings of power ( Morgan. 2006 ) . many of them could be projected on the instance. One of that is control of scarce resources including money. stuff. forces. and engineering ( Emerson. 1962 ) . Krane. as the divisionââ¬â¢s accountant. had the control to apportion resources including wages. disbursals. and information systems. She had extra beginning of power that represents a structural factor that defines the phase of histrions ( Bachrach A ; Baratz. 1962. 1970 ) . This beginning of power came from her being monitored. non merely by Moore. but besides by Arthur Silver. the main fiscal officer. Therefore. she had more considerable power to accept or reject any thought. which interprets her confident reactions during the meeting. Fale. as the frailty president of production. had besides the power of engineering ( Child. 1985 ) . boundaries ( Millar A ; Rice. 1967 ) and resources control ( Emerson. 1962 ) . He had besides the ability to ge t by with uncertainnesss ( Hickson et al. . 1971 ) . His contemplations were cardinal and referral. since he managed the production procedures and could judge any suggestion wanted to be implemented. Fale had extra power of interpersonal confederations ( Pfeffer A ; Salancik. 1978 ) . which is represented by his friendly relationship with Frank Oââ¬â¢Brien. the frailty president of forces. They used to hang out with each other for angling. When Frank changed his place during the meeting. Fale became more flexible to accommodate with Walkinsââ¬â¢ proposal. That reflects a serious impact of interpersonal confederations within the organisation ( Pfeffer A ; Salancik. 1978 ) . Krane and Fale had the power of Mooreââ¬â¢s trust in run intoing their promises ( Bachrach A ; Baratz. 1962. 1970 ) . In the same context. Walkins had besides the power of information and cognition ( Crozier. 1964 ) . which is represented by his familiarity to the market tendencies and competitory advantages. Moore admitted his endowment and that was besides extra credits for Walkins. Bing the divisionââ¬â¢s gross revenues director. Holly had besides the power of cognition and networking ( Pfeffe r A ; Salancik. 1978 ) . He could lend in the solution by happening new clients. His direct exposure to the market added more power to him. In general and as a direction squad. all directors had the power of the usage of organisational construction. regulations. and ordinances ( Crozier. 1964 ) . But Moore might hold the biggest portion of power. non merely due to him being a general director. but besides as a descendent of the household to the full owned the division ( Kanter. 1977 ) . He controlled the determination doing procedure wholly ( Bachrach A ; Baratz. 1962. 1970 ) . He started that by analysing the job. Then. he motivated the directors to portion their ideas. Finally. he ended up with choosing the most efficient solution that might accommodate the client orientation and budget. 5. CONCLUSIONSEven though the organisational political relations may be recognizable by everybody within any organisation. it is really rare to discourse it openly ( Morgan. 2006 ) . The instance of Chattanooga shows clear illustrations of subjects discussed in private. as we found when the caputs of sections questioned the competency and trustiness of each other. As discussed before. we can acknowledge that it is necessarily that political relations is indispensable characteristic of organisational life. The political metaphor emphasizes that the usage of power is cardinal of organisational analysis. The metaphor helps to better understand organizationsââ¬â¢ reason. as it enforces the thought that actions within organisations are more political than rational ( Morgan. 2006 ) . In Chattanooga. each director suggested solutions so that to increase the benefits for his/her section instead than the benefit for the division as a whole. Furthermore. the political metaphor helps to happ en solutions to the thought that organisations are incorporate constructions. which is non ever the instance ( Morgan. 2006 ) . Moore failed to merely use the collaborative values of squad work in Chattanooga. while that worked successfully when he worked at National Geographic. The political metaphor focuses on involvements. struggles and beginnings of power in order to understand and pull off them ( Morgan. 2006 ) . That besides helped Moore to understand the force drivers within the division. Finally. the metaphor has great influence to actuate persons to move politically. The chief drawback of utilizing the political metaphor is frights of change overing every activity within organisations into political Acts of the Apostless. This may sometimes make ambiance of uncertainness and misgiving ( Morgan. 2006 ) . That appears in the Chattanooga instance when most of troughs reflected negative feelings about each other. Another restriction is that the coevals of penetrations through different involvements possibly misused to accomplish personal ends. Last. but non least. it is complex to cover with pluralismââ¬â¢s inquiry. As a consequence. the political metaphor must be used carefully ( Morgan. 2006 ) . 6. Reference Bachrach. P. and Baratz. M. S. ( 1962 ) . â⬠Two Faces of Power. â⬠American Political Science Review. Bachrach. P. and Baratz. M. S. ( 1970 ) . Power and Poverty. New York: Oxford University Press. Bacharach. S. B. and Lawler. E. I. ( 1980 ) . Power and Politics in Organizations. San Francisco: Iossey-Bass. Bacharach. S. B. and Lawler. E. I. ( 2000 ) . Organizational Politics. Stamford. Connecticut: IAI Press. Benson. I. K. ( 1973 ) . ââ¬Å"The Analysis of Bureaucratic-Professional Con?ict. â⬠Sociological Quarterly. Brown. L. D. ( 1983 ) . ââ¬Å"Managing Con?ict Among Groups. â⬠pp. 225-237 in D. A. Kolb. I. M. Rubin. and Mclntyre. I. Organizational Psychology. Englewood Cliffs. Nickel: Prentice Hall. Buroway. M. ( 1979 ) . Manufacturing Consent. Chicago: University of Chicago Press. Burrell. G. and Morgan. G. ( 1979 ) . Sociological Paradigms and Organizational Analysis. London: Heinernann Educational Books. Child. I. ( 1935 ) . ââ¬Å"Management Strategies. N ew Technology and the Labour Process. â⬠in D. Knights. H. Willmott. and Collinson. D. Job Redesign. Aldershot. United kingdom: Cnnlpr. Coser. L. A. ( 1956 ) . The Functions of Social Con?ict. New York: Routledge A ; Kegan Paul. Crozier. M. ( 1964 ) . The Bureaucratic Phenomenon. London: Tavistock. Culbert. S. and McDonough. I. ( 1980 ) . The Invisible War: Prosecuting Self-Interest at Work. Toronto: Iohn Wiley. Emerson.
Friday, September 27, 2019
To what extent did the liberalisation policies adopted by Coursework
To what extent did the liberalisation policies adopted by Czechoslovakian politicians cause the Prague Spring - Coursework Example In spite of the severe crushing of the reforms, the period of Prague Spring is cherished in the history of the country as a breakthrough in the dictatorship climate during the time and as a harbinger of hope for the people of not only Czechoslovakia, but also of Hungary and Poland. The available literture on the history of Czechoslovakia reveals that Prague Spring was not the result of just the change in the political will of the government, but it had several antecedent conditions that led to it. These antecedents are deeply rooted in the history of Czechoslovakia starting after the World War I in 1919 and the political decisions and forces that shaped the destiny of the nation for the next three decades upto the 1950s. This paper aims to understand the causes that led to the Prague Spring and also to assess if the liberalization policies of politcians played an active role in its inception. In rder to evaluate if the liberalization policies adopted by Czechoslovakian politicians ca use the Prague Spring, it is important to understand the antecedent conditions in Czechoslovakia with respect to the socio-economic and political environment. Political Decision Making in Czechoslovakia Leading Up To the Prague Spring Czechoslovakia had come into existence as an independent country after the fall of the Habsburg monarchy after the World War I (Evans, 1979). The new formed Czechoslovakia was characterized by parliamentary democracy and a strong center of government and a robustly growing economy (Windsor and Roberts, 1969). However, the political turmoil in the neighboring countries, hostile neighbours like Hungary, Poland and Germany, and the impeding march of the Hitlerââ¬â¢s forces towards Czechoslovakia all added to insecurities about the future of Czechoslovakia. In addition, the country faced internal ethnic and religious tensions and economic inequalities between its Czech and Slovak people. The World War II saw the occupation of Czechoslovakia by Germany, and later liberation of the country with help from teh Russian Army (Ramet 1999). Thus, post the World War II Czechoslovakia was placed in the power of the Soviet Union and its political and economic policies oriented towards communism. Czechoslovakia soon moved towards a socialist regime and the political set up went into the hands of the socialist parties (Davies, 2007). The coalition consitsed of both the socialist and the communuist elements and it initiated economic policies favoring socialism. This was the time when the people of Czechoslovakia were optimistic of their future as an emerging economy and a free country (Chad, 2007). However, within a decade Czechoslovakia was overtaken by the communist party and a regime of purging the politics of all non-communist elements was set into motion (Davies, 2007)). During the communist era, Czechoslovakia invested greatly in the development of heavy industries and acquired an inmressive growth rate of 170 percent . By 1948, Stalinsâ â¬â¢ collectivism ecomomic policies greatly inspired Czechoslovakia which followed an approach of forced labour and excessive government control in the market (Segel, 2003). This was the dark period of repression of public opinion and freedom of speech in Czechoslovakia and led to the public simmering with resentment against the political approach. The
Thursday, September 26, 2019
Forensic Pathology Research Paper Example | Topics and Well Written Essays - 2000 words
Forensic Pathology - Research Paper Example and 6 million child abuse allegations in the United States (ââ¬Å"National Child Abuse,â⬠n.d.) These data prove that children are the common victims of abuse and maltreatment, which also lead to their early death. Considering that child abuse is one of the most rampant crimes today, medical and legal practitioners try to find scientific and legal procedures to solve child abuse cases. Pediatric forensic pathology, as a medico-legal investigation procedure, proves sufficient enough to solve child death due to abuses. Accordingly, this paper aims to study the historical development of pediatric forensic pathology and analyze the significant events and people that contribute to its development. This paper will also discuss the theories and methods in pediatric forensic pathology; additionally, with case report evidences, this paper will show and analyze the successes and failures of the application of forensic pathology methods. Medico-legal investigation in America was patterned after Englandââ¬â¢s Coroner System, which empowers the coroner (equivalent to a sheriff) to perform judicial and ministerial authority over a corpse (Fisher, 1993, pp. 6-12). As an English colony, the American justice and medical system were patterned after the English system; thus, the American and English medical and justice systems are very much alike. During the years 1950 and onwards, American forensic pathology had undergone several changes and innovations; these innovations had contributed to the growth and advancement of forensic sciences in the United States (Rudin & Inman, 2002). Two of the most significant events in the history of forensic pathology in America are the establishments of the American Academy of Forensic Science (AAFS) in Chicago and the printing of the Journal of Forensic Science (JFS) in 1950. These were followed in 1966 by the discovery of the immunoelectrophoretic technique used to identify bloodstains; this technique was developed by Brian J. Culliford and Brian
Management accounting Essay Example | Topics and Well Written Essays - 2000 words - 3
Management accounting - Essay Example The economy is subject to market forces and that means that factors affecting the nation such as inflation can cause the changes. An economy may turn out to be favorable or unfavorable. That means that there may be a lot of money in circulation and that will make the customers to purchase more of the product. The other aspect of the economy that will cause a variance is the standard of living. If the standard of living among people improves, that will imply that the customers will be able to purchase more of the product and that will make the actual results to be better than the budgeted. In our case, the actual profit was less than the budgeted that implies that the economy could have worked against the sales. The economy can also cause an increase in the cost of raw materials. In our case, the raw materials turned out to be more expensive than the budgeted expenses. That indicates that the economy worked against the budget of the company. In the future, the company should consider inflation and its impact when formulating the budget. The trends in the economy should also be observed to ensure that all matters affecting the economy are considered. 2. Advertising- Advertising involves making known the products of a company to its target and potential clients. That means that the aim of carrying out an advertisement is to increase the sales volume of a product. Advertising will increase the sales volume if it turns out to be as productive as expected. A company should invest in advertising to ensure that it reaps the benefits that are associated with advertising. In our case, the profits of the company turned out to be less than the budgeted profit. That means that the advertising efforts were not as productive as expected. That can also imply that the company did not carry out adverting. This is because the sales volume was less than the budgeted sales volume. In the future, the company should formulate a strong advertising campaign. The advertising will
Wednesday, September 25, 2019
Education of Looked after Children Essay Example | Topics and Well Written Essays - 2500 words
Education of Looked after Children - Essay Example This essay stresses that councils are judged on the proportion of children and young people who are engaged in education, training or employment at the age of nineteen. Again, performance against that indicator is improving. Although it is important to focus on these indicators as useful in helping authorities assess their performance it is also essential that local authorities as corporate parents have high expectations of the children and young people in our care, and that these include but also go beyond educational attainment. This paper makes a conclusion that certainly some of the poor achievement can be explained by a range of other factors, looked after children are more likely to be from groups that traditionally tend to do less well in education, and they are more likely to have special educational needs and to be statemented. The performance assessment framework indicators do adjust for these factors which demonstrate that even taking these into account looked after children as a group are not doing as well as their peers. With the improvement in the early support available to families, fewer children will face such adverse experiences and that a greater number can be supported safely within their families. Research also suggests that there is often room for children's services to act more decisively at earlier stages in children's lives. The children can be at risk of underachieving at school because they have experienced disruption to their family life and education. Growing up can be a bewilderin g and confusing time for those persons who are in the care system. It is important to make sure that they receive the support, guidance and encouragement that they need. Some may have low expectations, poor emotional and psychological health and a lack of family support. Education is an important pathway to a better life for them. Each local
Tuesday, September 24, 2019
Many microbial infections are described as opportunistic. What do you Essay
Many microbial infections are described as opportunistic. What do you understand by this termGive a bacterial, parasitic - Essay Example At this time, the opportunistic organisms get an opportunity to spread as well as grow fast, hence, causing severe illness. Though such infections can be seen in a healthy person, their growth and spread is highly hindered. In cases of opportunistic infections, a chance is created for nonpathogenic microorganisms to become pathogenic and very harmful (Mitnick et al, 2003, p. 119). These infections mostly manifest themselves in people already infected with viruses like HIV, for instance Tuberculosis (TB). Tuberculosis (TB) as an Opportunistic Infection Viral Example Tuberculosis is an air-borne disease that usually affects the respiratory system (lungs) and is caused by Mycobacterium Tuberculosis bacteria (Currie et al, 2003, p. 2501). It can also affect other body parts like the spine and the kidneys. It is a serious infection that kills a large percentage of people worldwide, especially if not effectively treated. Approximately 2 billion people of the worldââ¬â¢s population give positive results to TB tests annually, of which about 3 million end up dying. TB infections had almost become extinct in developed countries before the emergence of HIV epidemic. With the onset of the HIV virus, TB infections were found to be very rampant and severe in people affected with the virus (Jones et al, 2000, p. 1031). This is simply because the HIV virus makes the bodyââ¬â¢s immune system weak, thus, promoting the growth and spread of the TB bacteria. The close link between HIV and TB was stressed and emphasized during a conference concerned with retroviruses as well as opportunistic infections (CROI) (Mitnick et al, 2003, p. 128). At the conference, a report was release analyzing the recent emergence of TB bacteria which is drug resistant. The World Health Organization (WHO) tried to establish the relationship between this drug-resistant bacteria and the HIV virus. A study was carried out in South Africa where it found out that XDR TB was resistant to a number of drug s meant to treat it, including isoniazid. This was the new case which was discovered however since then beyond 300 new cases have been reported (Tufariello, Chan & Flynn, 2003, p. 578). Nevertheless, it was discovered that people who exhibited such cases positively tested for the HIV virus. The micro-organism that usually causes TB is transmitted from one person to another through air (CDC, 2000, p. 185). These micro-organisms can spread as a result of a cough or sometimes an open sneeze. It is not in all cases that a person can get infected with TB by just a single sneeze or a cough. However, if you are frequently exposed to such sneezes and coughs, the likelihood is very high. This can occur in cases where you live or mostly work with a TB infected individual. Moreover, you can easily get TB in places that are ventilated poorly or crowded (Espinal et al, 2000, p. 275). By so saying, it does not mean that one can get infected through sharing utensils or physically contacting a pers on who has it. There are mainly two types of infections classified as TB which are differentiated using their different ways of manifestations (Lonnroth et al, 2009, p. 2240). The first one is referred to as latent and this one has no symptoms thus remains in your body in an inactive form. The second one is called active which mostly affects people whose immune system is impaired. In this case,
Monday, September 23, 2019
Planning and the Law Essay Example | Topics and Well Written Essays - 3000 words
Planning and the Law - Essay Example From the research it can be comprehended that development of architectural planning and legal control on building construction in England has a long history which dates back to around 1180s. This history has generated accounts of interest for building enthusiasts. The legal control on building construction began in the English capital London which was densely populated. The buildings in the city were densely packed creating so many problems in the city and could only be solved communally. Houses could be built with thin party walls and poorly sited privies as well as gutters which could cause nuisances to the neighbors. In addition, there were complaints from the residents that one house could block light from the other. For this reasons, the authorities decided to set up building regulations that could give guidelines on building construction this was as early as 1189. During this medieval time, the greatest risk was fire outbreaks. In 1212, there was a devastating fire which huge d estruction in the city, the mayor of the city could regularly received complaints about building nuisance by one neighbor against the other. The problem of country and town planning in England worsened during the profound revolution which the country went through during the nineteenth century. The revolution in England brought about enormous growth of the countryââ¬â¢s population especially in the urban centers.... The influx of people in the industrial town was partly as a result of the decline in agricultural activities in the countryside especially after 1850. At the begging, the conditions around the newly founded industrial towns were very appealing. For this reason, houses as well as industries drastically sprung up and were built side by side and no efforts were made for purposes of zoning or planning so to speak. People had to live within their places of work and thus they build their houses around the industries. Worse still, nobody seemed to care about the standards of building construction or even sanitation of the area. The haphazard construction of the houses and industries encouraged the spread of various diseases causing devastating outbreaks of typhoid and cholera in the industrial towns. Following the cholera epidemics that lead to loss of many lives, several commissions were formed to inquire on the causes and to give possible recommendation. Several reports were published suc h as the report by the Poor Law Commissioners in 1838and the Royal commission on the Health of Towns in 1842. These publication and other led to the enactment of a couple of legislations by parliament related to building construction in the country. Even though these Acts covered limited scope, as well as effects, they were significant in laying the basis of enduring legislative restrictions on the freedom of those who owned land to construct buildings as the deemed fit. A General Board of Health was established under the Public Health Act of 1848. This board was charged with the responsibility of ensuring that both the existing and new buildings provided
Sunday, September 22, 2019
Creative Intelligence Essay Example for Free
Creative Intelligence Essay 1. Introduce change Discover new solutions Make ideas exciting Work best with people 2. My strength is being Decisive Thorough Imaginative Understanding 3. Successful people are Ambitious Disciplined Willing to take risks Self-confident 4. I get my best results by Focusing on current problems Applying careful analysis Trying new products Gaining the support of others 5. I see the future as Unknown A challenge Providing many opportunities Facilitating change 6. I appreciate teachers who Explain ideas clearly Making learning interesting Recognize original ideas Involve others in learning 7. People see me as Energetic Persistent A perfectionist Committed 8. People who make things happen Are highly motivated Enjoy experimenting Have the courage of conviction Challenge the status quo 9. Discoveries depend on Being committed Being curious Being open-minded Having a broad perspective 10. A good writer Is convincing Presents new ideas Provides a unique perspective Has a compelling vision 11. Breakthrough thinking Makes progress possible Helps to solve difficult problems Explores new frontiers Encourages teamwork 12. I dislike 13. I communicate best by being 14. I am committed to 15. Creative organizations 16. Achieving results depends on being 17. I prefer situations where I 18. Change depends on 19. My goal is to 20. Leaders 21. Ethical Behavior 22. The arts 23. Creative thinkers 24. Breaking with tradition 25. When under pressure, I
Friday, September 20, 2019
The Construction Material Concrete Construction Essay
The Construction Material Concrete Construction Essay The process of curing concrete, handling it in different climatic conditions and the various diseases that can arise in concrete structures are the key points of this paper. The word concrete is derived from a latin word concretuswhich means compact or condensed. Concrete is a thick composite artificial stone like material which is made by mixing cement (generally Portland cement) and various other aggregates, such as sand, pebbles, gravel, shale, etc., with water and allowing the mixture to harden by hydration. Since the ancient times it had been used in constructing structures and today also it is used more than any other man made construction material in the world. COMPOSITION Depending upon the reqirement of the structure,the proportions of the main ingredients discussed below are varied to avail different types of concrete. By doing so the finished product can be tailored to its application with varying strength, density, or chemical and thermal resistance properties. CEMENT Portland cement is a basic ingredient of concrete. It consists of a mixture of oxides of calcium, silicon and aluminium. Portland cement and similar materials are made by heating limestone (a source of calcium) with clay, and grinding this product (called clinker) with a source of sulfate (most commonly gypsum). WATER When water is added in a cementitious material, cement paste is formed through the process of hydration. The cement paste glues the aggregate together, fills voids within it, and allows it to flow more smoothly. Water should be added in the mix very carefully as less water in the cement paste will yield a stronger, more durable concrete; more water will give an free-flowing concrete with a higher slump. Impure water used to make concrete can cause problems when setting or in causing premature failure of the structure. In the process of hydration many different reactions occur at the same time. As the reactions proceed, the products of the cement hydration process gradually bond together the individual sand and gravel particles, and other components of the concrete, to form a solid compact mass. AGGREGATES The presence of aggregate greatly increases the robustness of concrete above that of cement.Following are the different items which could be used as aggregates: Sand, natural gravel and crushed stone Recycled aggregates (from construction, demolition and excavation waste) and manufactured aggregates like air-cooled blast furnace slag and bottom ash Decorative stones such as quartzite, small river stones or crushed glass are sometimes added to the surface of concrete for a decorative exposed aggregate finish. CURING OF CONCRETE The term curing concrete signifies the process of stopping freshly poured concrete from drying out too quickly. Unless the concrete mass is not cured, or if it is left out to dry out on its own, it will not develop the full bond between all of its ingredients. In order to form a water cement paste, water is added in Portland cement after which chemical reactions take place in the mixture turns the paste into a bonding agent. This reaction is known as hydration and it produces a stone-like compact substancethe hardened cement paste. Both the rate and degree of hydration, and the resulting strength of the final concrete, depend on the curing process that follows placing and consolidating the plastic concrete. As long as the mixture contains water and the temperature conditions are favorable, the process of Hydration continues ,though at a decreasing rate . The strength of concrete is dependent on crystal growth within the concrete matrix through the process of hydration If water is not adequate, the crystals cannot grow, due to which the concrete is unable to attain the desired strength. The presence of water through proper curing of the concrete facilitates the crystal growth that encloses the gravel and sand mix, causing interweaving with each other. .The time-span of the process of Curing begins from the time of consolidation and ends at the point where the concrete reaches its design strength. The period can vary from a few days to a month or longer. For most structural use, the curing period for cast-in-place concrete is usually 3 days to 2 weeks. During this period, the concrete mass should be kept moist and as near 73F as practical. Bridge decks and other slabs exposed to weather and chemical attack usually require longer curing periods. The time span of the curing period also depends on the factors such as type of cement used mix proportions required strength size and shape of the concrete mass weather conditions and temperature future exposure conditions SIGNIFICANCE OF CURING A proper and effective curing process helps in improving various properties of concrete such as freeze and thaw resistance strength watertightness wear resistance volume stability. Serviceability and apperance The compressive strength of concrete that has been properly cured is 75 to 95 per cent more than the concrete that has not been cured. Figure 1 illustrates this by comparing the compressive strength of concrete(at 180 days) for which the surface has been either kept moist for the entire duration of 180 days or is kept moist for various periods of time and allowed to dry out or is allowed to dry out from the time it was first made.It is quite clearly depicted that the compressive strength of the concrete is highest when it is fully cured for the entire period of 180 days. Fig 1:Moist curing effect on compressive strength of concrete source:www.tpub.com The permeability and absorptivity of concrete mix depends upon the porosity of the mix ie whether the pores and capillaries are discrete or interconnected. The porosity of the mix is reduced overtime through proper and effective curing of concrete thereby increasing the durability of concrete. Also, proper curing of concrete mix will reduce crazing, dusting and scaling of the slab thereby ensuring better serviceability and appearance. STAGES IN CURING PROCESS After the concrete mix have been placed, it is imperative to keep it moist and maintain specified concrete temperatures.The process of curing starts immediately after the placement of concrete and it goes through two stages : Initial curing stage: time of placement to initial set. This stage would include all the deliberate action taken between placement and final finishing of concrete. Approximate conditions during the initial curing period should be forecast prior to construction. Under this stage,the rate of strength gain of the concrete is minimal. The various aspects to be dealt with construction initial curing period as shown in diagram below are : verifying evaporation conditions: concrete temperatures, wind velocity, air temperature, and relative humidity are required to be taken into account during placement. These elements are used to make nomograph to calculate the evaporation rate and to determine whether critical drying rates exist. Using the concrete placing temperature, the time of initial setting can be estimated. The time of initial setting is the optimal time for application of final curing. Major items requiring attention during construction-initial curing period. Source : www.fhwa.dot.govt Onsite adjustments for Excessive drying: In order to reduce evaporation rates of bleed water the following two adjustments could be made- reducing concrete placing temperatures- Cooling aggregate stockpiles, cooling mixing water, or using ice for mixing water are very effective ways of reducing concrete temperatures. use of evaporation reducers. Evaporation reducers are water emulsions of film-forming compounds. The film-forming compound is the active ingredient that slows down evaporation of water. There is also a benefit from the water fraction of the evaporation reducers, in that it compensates to a small degree for losses of mixing water to evaporation.Evaporation reducers may need to be applied several times, depending on the conditions. Concrete that are liable to quick drying is required to be covered with wet gunny bag or wet hessian cloth properly squeezed, so that the water does not drip and at the same time, does not allow the concrete to dry. This condition should be maintained for 24 hours or at least till the final setting time of cement at which duration the concrete will have assumed the final volume. The Final curing stage: The final curing period is defined as the time interval between application of curing procedures and the end of deliberate curing. Final curing methods fall into four categories: Water curing : Water curing can be done in various ways like immersion,ponding, spraying or fogging and wet covering.This is by far the best method of curing as it satisfies all the requirements of curing, namely, promotion of hydration, elimination of shrinkage and absorption of the heat of hydration. Curing a house slab by flooding. Source: http://www.builderbill-diy-help.com/curing-concrete.html The precast concrete items are normally immersed in curing tanks for a certain duration. Pavement slabs, roof slab etc. are covered under water by making small ponds. Vertical retaining wall or plastered surfaces or concrete columns etc. are cured by spraying water. In some cases, wet coverings such as wet gunny bags, hessian cloth, jute matting, straw etc., are wrapped to vertical surface for keeping the concrete wet. For horizontal surfaces saw dust, earth or sand are used as wet covering to keep the concrete in wet condition for a longer time so that the concrete is not unduly dried to prevent hydration. The diagram below summarises the major criteria for using water-added curing methods. Major features of curing with added water. Membrane curing : this curing method is mostly used when there is less availability of water in the region where curing is done. Under this method, concrete could be covered with membrane which will effectively seal off the evaporation of water from concrete. A continuous seal over the concrete surface is maintained by means of a firm impervious film to prevent moisture in concrete from escaping by evaporation. Some of the materials, which can be used for this purpose, are bituminous compounds, polyethylene PLASTIC SHEETING source:www.builderbill-diy-help.com or polyester film, waterproof paper, rubber compounds etc. When waterproofing paper or polyethylene film are used as membrane, care must be taken to see that these are not punctured anywhere and also see whether adequate lapping is given at the junction and this lap is effectively sealed. Application of heat : When concrete is subjected to higher temperature it accelerates the hydration process resulting in faster development of strength. Concrete cannot be subjected to dry heat to accelerate the hydration process as the presence of moisture is also an essential requisite. Therefore, subjecting the concrete to higher temperature and maintaining the required wetness can be achieved by subjecting the concrete to steam curing. The exposure of concrete to higher temperature can be done by Steam curing at ordinary pressure, Steam curing at high pressure ,Curing by Infra-red radiation ,Electrical curing. Traditional steam curing of concrete pipes (www.construction-int.com) Miscellaneous : Calcium chloride is used either as a surface coating or as an admixture. It has been used satisfactorily as a curing medium. Both these methods are based on the fact that calcium chloride being a salt shows affinity for moisture. The salt not only absorbs moisture from atmosphere but also retains it at the surface. This moisture held at the surface prevents the mixing water from evaporation and thereby keeps the concrete wet for a long time to promote hydration. Formwork prevents escaping of moisture from the concrete, particularly, in the case of beams and columns. Keeping the form work intact and sealing the joint with wax or any other sealing compound prevents the evaporation of moisture from the concrete. This procedure of promoting hydration can be considered as one of the miscellaneous methods of curing. At the end of the curing process majority of cement gets hydrated.There is slow rate of compressive strength gain of around 50-100 psi/hours and little exothermic heat generation. In the entire process of curing if one of the curing procedures is used initially, it may be replaced by one of the other procedures after the concrete is 1 day old, provided that the concrete surface is not permitted to become dry at any time. After the termination of the curing process the adequacy of a curing program could be verified.Although strength is the primary variable around which curing specifications are based several other approaches can also be used like Surface Water Absorption: the amount of water a dry concrete specimen absorbs in the first minute or so after contact with liquid water is directly related to the quality of the curing of the near-surface zone of the concrete. This method has direct applicability to verifying curing. The method is reasonably applied to cores, which can be dried to a constant low moisture content before testing. Rebound Hammer: The rebound hammer method basically measures the modulus of elasticity of the nearsurface concrete. This may actually recommend the method for use in evaluating the curing of concrete pavements, where near-surface effects are considered most important. The test method is suitable for in-place measurements. Laboratory work has shown that rebound numbers of uncured concrete exposed to modestly severe drying are reduced by about 50 percent at 7 days relative to well-cured concrete. Strength of Cores: The strength of concrete is strongly affected by inadequate curing, and, in theory, could be detected by measuring strength of cores. the effects of poor curing are only strongly apparent in the properties of the top 50 mm of concrete, and sometimes even less. Ultrasonic Pulse Velocity: The ultrasonic pulse velocity (UPV) method is an indirect measure of the modulus of elasticity of concrete. The modulus of elasticity of concrete tends to increase with increasing hydration (or quality of curing) of the cement paste fraction of the concrete. UPV testing can be set up in a number of configurations, each of which tends to focus on slightly different features of the concrete. A simple pulse velocity taken through a piece of concrete, which is the traditional way of using UPV to investigate concrete properties, gives information on the average quality of the concrete. Abrasion Resistance: The degree of curing has been shown in numerous research publications to be strongly reflected in the abrasion resistance of the cement-paste fraction of concrete. This truth is easily verified qualitatively using an electrically powered wire brush and observing the ease with which the near-surface mortar can be removed from a small spot of concrete. Poorly cured concrete is easily abraded away, while well-cured concrete is quite difficult to abrade away with such equipment. DISEASES OF CONCRETE Deterioration of concrete buildings is becoming a cause of concern now a days. Often the structures located along open water, lakes, rivers and oceans are extremely vulnerable to attack from the harsh environment i.e. salt, moisture, humidity, carbon dioxide, etc. cracks, spalls and rust stains are some of the visual symptoms of the deterioration of concrete. CRACK Crack is the most common diseases of concrete structures and it occurs as a result of material discontinuity. Thermal and shrinkage cracks can be associated with high cement content and high strength concrete. Usually cracks occur in the concrete structures due to various reasons such as excess water in the mix ,rapid drying of the concrete, improper strength concrete poured on the job, lack of control joints, if Concrete is poured on frozen ground, alkali-silica reactionetc. In order to prevent cracks in concrete structures, following preventive measures could be taken: Estimate in advance the quantity of water to be mixed to get the required concrete mix. Adding too much water in the mix is one of the main causes of cracked concrete Do not pour concrete on the frozen ground .A compacted subgrade could be used to pour concrete upon to prevent cracking Cut control joints into the concrete so that the slab will be able to shrink and expand with temperature changes. Control joints should be cut the same depth of the slab and spaced a maximum of three times the thickness of the concrete. The slab must retain enough moisture so that the drying and shrinking happens as slowly as possible in the days and weeks after pouring. Curing helps the concrete to retain moisture in the concrete so that it can continue to gain strength to resist cracking. CRACKS ON CONCRETE SURFACE Source:www.homebuildinginformation.com FROST When the concrete is critically saturated i.e. approximately 91% of its pores are filled with water then deterioration of concrete from freeze thaw actions may occur. When water freezes to ice it occupies 9% more volume than that of water.In case there is no space in concrete for this expanded volume , a kind of distress is caused which will result in loss of concrete surface. A surface active agent should be added to the concrete mixture in order to prevent frost in a concrete structure. This creates a large number of closely spaced, small air bubbles in the hardened concrete which would act as expansion chambers to relieve the pressure build-up. It is to be noted that concrete with high water content and high water to cement ratio is less frost resistant than concrete with lower water content. ABRASION AND CAVITATION Hydraulic Concrete structures are affected by Abrasion-erosion due to the action of debris rolling and grinding against surface. The sources of the debris include construction trash left in a structure, riprap brought back into a basin by eddy currents because of poor hydraulic design or asymmetrical discharge, and riprap or other debris thrown into a basin by the public. Mechanical abrasion is usually characterized by long shallow grooves in the concrete surface and spalling along monolith joints. general abrasion and cavitation erosion results in coarse aggregate exposed concrete surface, concrete uneven surface, resulting in holes. In order to prevent the structure to suffer from abrasion the concrete should include the maximum amount of the hardest coarse aggregate that is available and the lowest practical w/c. In addition to this,high-range water-reducing admixtures (HRWRA) and condensed silica fume have been used to develop high compressive strength concrete 97 MPa (14,000 psi) , at this strength the concrete mix assumes a greater role in resisting abrasion-erosion damage. Also vacuum-treated concrete, polymer concrete, polymer-impregnated concrete, and polymer portland cement concrete could also be used to increase the abrasion resistance. In existing structures, balanced flows should be maintained into basins by using all gates to avoid discharge conditions where eddy action is prevalent. ABRASION source:www.nrc-cnrc.gc.ca CARBONATION Carbonation is a chemical reaction between atmospheric carbon dioxide and hydrated cement compounds which causes a reduction in the alkalinity of the concrete. The permeability and moisture content of the concrete directly affects the rate of carbonation . Pop-corn like calcite crystals present in carbonated paste. source:www.concrete-experts.com In the process of carbonation the calcium bearing phases present in the concrete mass are attacked by carbon dioxide of the air and converted to calcium carbonate.In this process the alkalinity of the concrete is lowered from an initial pH of around 13.5 to around 8.5 over some years. One method of testing a structure for carbonation is to drill a fresh hole in the surface and then treat the cut surface with phenolphthalein indicator solution. This solution will turn [pink] when in contact with alkaline concrete, making it possible to see the depth of carbonation. In order to combat the process of carbonation aquron products from Allcrete industries could be used which helps in the following ways seals out moisture to a depth of 100mm or more reduces oxygen permeability by a pore-blocking process brings up the alkalinity of the concrete purging and binding chlorides in the colloidal silicate hydrogel formed in the pores and capillaries of the concrete It is to be noted that when Concrete is treated within 24 hours of casting ,it will be protected for life against carbonation problems and aged concrete, once treated, will become immune to further deterioration. CORROSION Corrosion of steel reinforcement in concrete structures is well known to be Concrete Cancer, which happens to be a significant area of concern in the area of infrastructure and building across the world. Corrosive species can enter the concrete mix if the ingredients of the concrete mix such as water, aggregates, additives are contaminated.When such corrosive species reacts with the chemical compounds under the porous nature of concrete,the problem of corrosion occurs. Corrosion damage to the reinforcing steel results in the build-up of voluminous corrosion products, generating internal stresses and subsequent cracking and spalling of the concrete as shown schematically in the diagram below: Figure 2source:www.corrosion-club.com source:www.zoranthepainter.com Corrosion mechanism Concrete Cancer The most frightening thing is that the corrosion can be going on under the surface and will not be noticed until the concrete starts visibly disintegrating. The outcome of such corrosion is that concrete reduces its strength and also the steel re-enforcing within the concrete can rust and the pressure this creates can cause the concrete to crack and crumble. Buildings in coastal areas are especially at risk. The preventive measures to avoid such kind of concrete cancer are listed below: Epoxy coating: The concrete structures that are exposed to deicing salt may benifit from use of epoxy-coated, hot dip galvanised or stainless steel rebar. Epoxy coated rebar can easily be identified by the light green colour of its epoxy coating. Applying Sealants: After the process of curing, penetrating sealants must be applied. Sealants include paint, plastic foams, films and aluminum foil, felts or fabric mats sealed with tar, and layers of bentonite clay, sometimes used to seal roadbeds. corrosion inhibitors: calcium nitrite can also be added to the water mix before pouring concrete. Generally, 12 wt. % of calcium nitrate with respect to cement weight is needed to prevent corrosion of the rebars. Extreme weather conditions such as high ambient and concrete temperature, low relative humidity or a mere 40 F or less average daily air temperature for more than 3 consecutive days, tend to impair the quality of freshly mixed or hardened concrete thereby giving detrimental results. Therefore, it becomes imperative to handle concrete with caution both in extreme hot and cold weather. EFFECTS OF HOT WEATHER AND PROPER HANDLING On the compressive strength: When the temperature of concrete is high cement hydrates at a much faster rate, it sucks up water and grows crystals around the aggregate particles but dont have time to grow strong . Although, the early strength will be higher but 28-day strength suffers. If the concrete is about 18 hotter than normal (for example, 88 instead of 70), the ultimate compressive strength of the mix will be about 10% lower. On the colors of integrally colored concrete: under hot weather conditions , slump decreases rapidly as the cement sets up and and more mixing water is needed. In integrally colored concrete,this can lead to variations in water content which can result in significant differences in concrete color between adjacent pours. Surface drying: high concrete temperature and hot dry wind across the concrete can cause more drying and surface shrinkage. Thermal differentials: sometimes the hot weather condition makes one part of the concrete mass warmer than another part. If this differential is greater than about 20F then concrete gets cracks. Difficulty in maintaining air content can be a problem in warm concrete. Mixing is more likely to drive air out of the concrete making the level difficult to control. Dealing with hot weather concreting Plastic shrinkage is a particular problem in hot weather concreting. As a general rule, each 10o F increase in ambient temperature reduces slump about 1. A switch from ASTM C494 Type A to Type D water reducing and set retarding mix may be part of an effective plan for hot-weather concreting. Aggregates forms a major part in a concrete mix so its temperature has the greatest effect on concrete temperature. Shading of aggregate piles is ideal, although not always possible. Using cool water is another way to get cool concrete. Ready mix producers in hot climates use chilled water or ice to lower the concrete temperature. Retarding admixtures can also contribute towards controlling concrete in warm weather. When the concrete is hot, the setting time is very quick .At that time Retarder can be added at the plant or on the job site . Retarders delays the setting time but they also give the concrete more time to dry out, so curing is critical. Retarders come as straight retarders or as water-reducing and retarding admixtures. Mid-range water reducers can increase the air content of the concrete. For concrete that is to be stamped, consider using step retardationadding retarder to the mix after half of the batch or after one-third and two-thirds have been placed. For textured concrete one of the strongest things to do in hot weather is step retardation. In order to avoid slump loss superplasticizer (high-range water reducer) could be used. These admixtures can increase slump without affecting the concretes final strength or appearance. Before placing the concrete on a subgrade wet down everything, subgrade and forms, with cool water so moisture isnt absorbed from the concrete, which can lead to cracking. In order to prevent the evaporation of surface water use a monomolecular film or evaporation retarder as soon as the concrete is down and bull floated. These materials evaporate after a couple of hours. Monomolecular film will prevent plastic shrinkage cracking and surface crusting. In hot and dry weather curing needs to start as soon as finishing operations are completed. A white pigmented curing compound could be used with plain gray concretein order reflect sunshine. Also the white curing blanket could be used for the same purpose. A white pigmented curing compound on plain gray concrete white curing blankets keep the concrete cooler by reflecting can help reflect some heat from the sun the sun In a hot climate, stain the concrete in the coolest part of the day as staining concrete relies on a chemical reaction that happens faster in hot weather.If concrete is stained in 95 to 100 weather ,it can ruin the entire job. Staining is best done early in the day when the concrete is cooler For an overlay installation it is advisable that the concrete surface temperature should be between 50 and 80.Installing an overlay during the hottest part of the day amidst direct sunlight could adversely affect the quality of the result. EFFECTS OF COLD WEATHER AND PROPER HANDLING During cold weather until the concrete gains compressive strength of 500psi , it is under threat of either getting freezed up which in turn could break up the matrix or the concrete mix sets at a very slow pace. Below 40F the hydration reaction basically stops and the concrete doesnt gain any further strength. when the ground is cold, the concrete in contact with it will be cold and will set more slowly. This can lead to the problem of crusting, with the top part of the concrete set and the bottom still soft. During the process of shifting the concrete mix from the ready mix plant to the job site there will be some heat loss. While placing concrete in cold it is advisable to remove all snow and ice from that area. Also any standing water should also be removed that could get mixed into the concrete. In case of a frozen land, it is advisable to thaw it using hydronic heat pipes and blankets (such as those from Ground Heaters), or electric blankets (check out Power Blanket). It is also suggested to Warm up anything that will come in contact with the concrete, including forms and any embedments, to at least 32F. Covering everything with tarps the day before the pour, will keep it dry and warm enough.also blankets could be used for the same purpose as well. Place triple layers of insulating blankets at corners and edges that could freeze. Wrap any protruding rebars. Make sure the blankets wont blow off during the night. Ground heaters Inc Portland cement association While placing decorative concrete in cold weather it is suggested to use a dial pocket thermometer or an infrared thermometer to test the concrete temperature as it is needed to be kept above 50F for the concrete to keep gaining strength. Also on exterior concrete, customers should be reminded to keep deicing chemicals off the surface during the first winter. Deicers can lead to spalling of newer concrete. During the process of finishing concrete in cold weather, it is advisable to let all the bleed water to evaporate first otherwise water-cement ratio would increase surface of concrete would get weak. Bleed water is basically the concrete particles settling (like mud in a stirred up pond) and squeezing out all the extra water. Vacuums can also be used for this purpose. It should also be noted that sealing concrete in cold weather conditions is very risky. Power blanket Layfield Group In order to keep the slab warm hydronic heating pipes or electric heating blankets could be used. These are laid on top of the slab and insulated. Also, in case it is too cold to even place the concrete, then the only option left is to enclose the work and heat the air. In case of an enclosure,it is required to consider the potential problem of carbonation. With unvented heaters (salamanders), or even with gas-powered equipment, the carbon dioxide levels can increase. This carbon reacts with the concrete, creating a chalky carbonated layer at the surface which is unacceptable. To fix this problem use heaters that exhaust to the outside of an enclosure or building and just blow in warm air. Maintain the concrete temperature above 40 degree
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