309 research outputs found
Foreword
The demand for air conditioning keeps rising, especially in developing countries where the standard of living has improved. This results in an increased consumption of electricity and puts further pressure on the power grid. In Cuba, electricity is a scarce commodity and the electricity production relies heavily on fossil fuels, which causes high emissions. An alternative technology for producing cooling is thermally driven cooling where the installment of an absorption chiller could utilize waste heat from existing industries to provide cooling to buildings. Therefore, there are possibilities of lowering the amount of electricity needed for air conditioning. In this thesis, the potential of using waste heat from sugar mills in Cuba was investigated. The sugar industry is high water consuming and often produces large amounts of heated waste water that is rarely utilized. To collect the data needed for the investigation, a study visit was conducted at the sugar mill Carlos Baliño in Villa Clara, Cuba. Since the factory did not track water mass flows, calculations based on sugar concentrations and energy balances were used to determine the different water outlets. The identified excess water has a mass flow of 10 kg/s and a temperature of 96 °C, which is enough to supply the factory with cooling. The result of the investigation also showed that the mill could invest in thermally driven cooling with a payback time of between three to six seasons depending on the cost of the selected equipment. The energy savings per crushing season would be nearly 140 000 kWh which equals to financial savings of above 40 000 dollar per season. If the sugar mill Carlos Baliño would invest in an absorption chiller, the cooling supply would be unreliable because of the high number of production shutdowns. Before any possible implementation, the causes for the stops in production need to be further examined. The supply of cooling would otherwise have to rely on thermal energy storage of chilled water, which in such large quantities would be costly. The factory only produces waste heat during the crushing season, which lasts from December throughout April, but there is a cooling demand during the whole year, which means that alternative cooling methods for an off-season cooling supply would have to be investigated. The study concludes that thermally driven cooling would be very suitable for similar industries that also produce large amounts of heated excess water, but are operating all year around and have a more even production rate, both on a daily and seasonal basis.EfterfrÄgan pÄ luftkonditionering fortsÀtter att öka, speciellt i utvecklingslÀnder dÀr levnadsstandarden har förbÀttrats. En ökad efterfrÄgan pÄ luftkonditionering resulterar i en ökad anvÀndning av elektricitet, vilket i sin tur leder till en ökad belastning pÄ elnÀtet. PÄ Kuba Àr elektricitet en bristvara och elproduktionen Àr starkt beroende av fossila brÀnslen vilket leder till stora utslÀpp. En alternativ teknologi för att producera kyla Àr vÀrmedriven kyla dÀr en absorptionkylmaskin kan utnyttja spillvÀrme frÄn redan existerande industrier för att leverera kyla till byggnader. DÀrav finns det möjlighet att minska anvÀndandet av den elektricitet som behövs för att driva luftkonditioneringsapparater. I denna uppsats undersöks potentialen för att anvÀnda spillvÀrme frÄn sockerfabriker pÄ Kuba. Sockerindustrin konsumerar stora mÀngder vatten och producerar ofta betydande kvantiteter av uppvÀrmt eller förÄngat spillvatten som sÀllan utnyttjas. För att samla in de data som krÀvs för undersökningen genomfördes studiebesök pÄ fabriken Carlos Baliño i Villa Clara, Kuba. Eftersom vattenflöden inte mÀttes i fabriken baserades berÀkningarna pÄ sockerkoncentrationer och energibalanser för att faststÀlla utloppsflöden av vatten. Det identifierade spillvattnet har ett massflöde pÄ 10 kg/s och en temperatur pÄ 96 °C, vilket Àr tillrÀckligt för att förse fabriken med kyla. Resultatet av undersökningen visade ocksÄ att fabriken skulle kunna investera i vÀrmedriven kyla med en Äterbetalningstid pÄ mellan tre till sex sÀsonger beroende pÄ kostnaden för vald utrustning. Energibesparingarna per produktionssÀsong skulle bli nÀrmare 140 000 kWh vilket motsvaras av en ekonomisk besparing pÄ drygt 40 000 dollar per sÀsong. Om en absorptionskylmaskin skulle implementeras pÄ Carlos Baliño skulle leveransen av kyla vara osÀker pÄ grund av det höga antalet produktionsstopp i fabriken. Före en eventuell implementation mÄste orsakerna till stoppen undersökas, annars skulle kylningsmöjligheterna bero starkt pÄ termiska energilager av kallt vatten vilket i stora volymer kan bli kostsamt. Fabriken producerar endast spillvÀrme under produktionssÀsong vilket pÄgÄr frÄn december till och med april men kylbehovet existerar under hela Äret. Det betyder att alternativa kylmetoder behöver undersökas för att kylbehovet ska kunna tillgodoses Äret runt. Slutsatsen av studien Àr att vÀrmedriven kyla Àr en ytterst passande lösning för liknande industrier som ocksÄ ger upphov till stora mÀngder av varmt spillvatten men som producerar hela Äret och har en jÀmnare produktion, bÄde pÄ daglig basis och sÀsongsbasis
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Does the Supreme Court Matter? Civil Rights and the Inherent Politicization of Constitutional Law
More than a decade ago, in a colloquium sponsored by the Virginia Law Review, scholars of the civil rights movement launched a fierce assault on Michael J. Klarman\u27s interpretation of the significance of the Supreme Court\u27s famous school desegregation ruling in Brown v. Board of Education. Klarman\u27s backlash thesis, initially set forth in a series of law review and history journal articles and now serving as the centerpiece of his new book, revolves around two central claims. First, he argues that the advancements toward racial equality generally attributed to Brown were instead the inevitable products of long-term political, social, and economic transformations that would have undermined Jim Crow regardless of Supreme Court intervention. Second, he credits Brown with a role in this historical process only through a chain of indirect causation: the Supreme Court decision galvanized massive resistance and racial violence in the South, which civil rights activists capitalized upon by engineering televised confrontations that mobilized public opinion across the nation, which created the climate for the passage of the federal civil rights and voting rights legislation of the mid-1960s, which directly and profoundly transformed southern race relations. Although the contours of this general story are part of the standard historical narrative, firmly grounded in the secondary source literature and taught in almost every university classroom, Klarman\u27s specific charge that civil rights scholars have greatly exaggerated the importance of Brown set off a bit of a firestorm. The first wave, which accompanied the 1994 Virginia Law Review article, included not only the expected differences of historiographical analysis but also criticism of a surprisingly personal nature. The response by David J. Garrow, titled Hopelessly Hollow History, ascribed Klarman\u27s views on Brown to the professorial urge for interpretive novelty, which often produces useful advancements but in some unfortunate cases results in revisionist interpretations whose rhetorical excesses are quickly revealed for what they are when old, but indisputable historical evidence, is inconveniently brought back to the pictorial foreground. Garrow highlighted Klarman\u27s failure to acknowledge the direct influence of Brown on the instigation of the 1955 Montgomery [bus] boycott, a causal analysis that emphasizes the crucial inspiration for southern black activists who finally had the moral authority and legal force of the Supreme Court on their side. While conceding Klarman\u27s point that Brown resulted in little school desegregation during the decade after 1954, Garrow blamed the Court itself for emboldening resistance to its decree through the infamous all deliberate speed implementation guidelines known as Brown II. Under this scenario, primary fault for the limited reach of Brown rested in the justices\u27 constrained vision of enforcement rather than in their premature placement of desegregation on the nation\u27s political agenda. In the final sentence of his rejoinder, Garrow dismissed Klarman\u27s entire project with undisguised condescension for the law professor treading on historians\u27 turf: [C]commentators would be well-advised to keep their professional desire for interpretive novelty in check, for rhetorically excessive overstatements and oversimplifications oftentimes do turn out to be hopelessly hollow once a fuller understanding of the historical record is brought to bear
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With All Deliberate Speed: Brown v. Board of Education
Julian Bond, former president of the NAACP and the first president of the Southern Poverty Law Center, delivered the Indiana University Maurer School of Lawâs Harris Lecture on Oct. 15, 2014 in the schoolâs Moot Court Room. Bondâs presentation, âThe Broken Promise of Brown,â was part of the schoolâs commemoration of the 60th anniversary of the landmark U.S. Supreme Court decision in Brown v. Board of Education
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Julian Bond, former president of the NAACP and the first president of the Southern Poverty Law Center, delivered the Indiana University Maurer School of Lawâs Harris Lecture on Oct. 15, 2014 in the schoolâs Moot Court Room. Bondâs presentation, âThe Broken Promise of Brown,â was part of the schoolâs commemoration of the 60th anniversary of the landmark U.S. Supreme Court decision in Brown v. Board of Education
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