Thesis (M.S.)--University of Wisconsin, 1973. / eContent provider-neutral record in process. Description based on print version record. Includes a bibliography.

Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xv, 183 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 133-134).

Thesis (MSc)--University of Stellenbosch, 2006. / Bibliography. Also available via the Internet.

To determine the effects of torso cooling with ice (ICE) or water-perfused (WP) vests during rest and warm-up on subsequent 1500 m time trial rowing performance in the heat. Eight male rowers (23 ± 4 y) completed 3 sessions on an ergometer in an environmental chamber (38ºC, 47% RH) 1 week apart. Pre-cooling was applied during rest (45 min) and warm-up (30 min) in 2 trials using ICE or WP vests, but not in the control condition (CON). Rectal (Tre) and skin (Tsk) temperature, HR, RPE, thermal comfort (TC) and sensation (TS) were monitored throughout. HR, RPE or TS were not different between conditions. TC, Tre and Tsk were lower in WP and ICE than CON post warm-up (P<0.05). The reduction in strain was reflected by increased power output during the 1500 m time trial in ICE (11±1.2 %) and WP (9.6±1.1%) compared to CON (P<0.05). Pre-cooling with ICE or WP vests enhanced performance in a 1500 m rowing time trial and power output was higher from the onset.

Orientador: Marcelo dos Santos Pereira. / Banca: Tomaz Manabu Hashimoto. / Banca: José Rubens de Camargo. / Resumo: No Brasil, as chapas para aplicação em vasos de pressão são produzidas com tratamento térmico de normalização. Devido às exigências de garantias de propriedades mecânicas após tratamento pós-soldagem, há necessidade de se adicionar elementos de liga, que podem segregar-se no centro da chapa. Uma alternativa é produzir chapas de aço pelo processo de resfriamento acelerado (processo termomecânico), mas que requer elevado investimento em equipamentos para as usinas nacionais. O resfriamento rápido logo após a normalização, seguido de revenimento, vem como alternativa para produzir chapas com propriedades mecânicas tão boas quanto às produzidas pelo processo termomecânico, sem a necessidade de adição de elementos de liga e de investimentos em equipamentos. Neste trabalho foram avaliadas as influências do resfriamento rápido nas propriedades mecânicas do aço, onde se verificou redução do tamanho de grão ferrítico, com possível formação de bainita. Obteve-se melhora no limite resistência à tração, limite de escoamento e na tenacidade do aço. Houve, porém, redução no alongamento e aumento da dureza do aço. Foi avaliada também neste trabalho a influência do tratamento térmico póssoldagem, onde se verificaram uma possível esferoidização da cementita e precipitação de cementita nos contornos de grão, reduzindo o limite de resistência à tração, escoamento e a tenacidade do aço, além da redução da dureza do aço. Verificou-se também aumento da tenacidade do aço, possivelmente pelo alívio das tensões residuais internas, ainda existentes após o revenimento. Não foi evidenciada a influência deste tratamento no tamanho de grão ferrítico do aço. / Abstract: In Brazil, plates for application in pressure vessels are produced by normalization heat treatment. Due to exigencies of guarantees of mechanical properties after postweld heat treatment, it is necessary to add alloy elements that can segregate themselves in the center of the plate. One alternative is to produce steel plates by accelerated cooling process (thermomechanical process), but it requires high investment in equipment for our national mills. Rapid cooling after the normalization, followed by tempering, turns up as alternative to produce plates with so good mechanical properties as those them produced by thermomechanical process, without the necessity of adding alloy elements and without investments in equipment. In this work were evaluated influences of rapid cooling heat treatment in the mechanical properties of the steel, where it was evidenced a reduction of the ferrite grain size with possible bainite formation. It was evidenced improvement in ultimate tensile strength, yield strength and tenacity of the steel. However, it was also evidenced reduction in the elongation and an increase of the hardness of the steel. It was also evaluated in this work the influence of post weld heat treatment, where if it was evidenced the possible occurrence of spheroidization of the cementite and precipitation of cementite in the grain boundary, reducing the ultimate tensile strength, the yield strength and the tenacity of the steel, beyond the reduction of the hardness. It was also evidenced an increase of the tenacity of the steel, probably because the residual internal stress relief, still existing into the steel plate after the tempering heat treatment. It was not evidenced the influence of this treatment in the ferrite grain size of steel. / Mestre

No description available.

Orientador: Sony Dimas Bicudo / Banca: Eunice Oba / Banca: Romildo Romualdo Weis / Resumo: Objetivou-se estudar os efeitos do extrato de lipoproteínas de baixa densidade sobre o sêmen ovino durante a refrigeração. Vinte amostras de 5 carneiros foram refrigeradas por 24 e 48 horas na geladeira para refrigeração Minitube, nos meios diluentes Glicina Gema Leite, Glicina Gema purificada Leite e Glicina Extrato Leite e submetidas a teste de exaustão (37ºC/240 minutos) sendo avaliados in vitro por meio das análises da cinética espermática computadorizada, da morfologia e da integridade da membrana plasmáticas. Após 24 e 48 horas de refrigeração, os meios Glicina Gema purificada Leite e Glicina Extrato Leite apresentaram resultados superiores ao meio Glicina Gema Leite, após o teste de exaustão, para o parâmetro de integridade de membrana plasmática. Para a integridade de acrossomo o meio Glicina Gema purificada Leite foi superior (P<0,05) em relação ao meio Glicina Gema Leite durante o teste de exaustão. Nos demais parâmetros estudados de cinética espermática e morfologia (cauda dobrada), não houveram diferenças significativas (P>0,05) entre os meios. Entre os momentos, houve diferença significativa (P<0,05) em todos os meios durante o teste de exaustão / Abstract: The objective was to study the effects of extract of low density lipoproteins on ovine semen during cooling. Twenty samples of five sheep were chilled for 24 and 48 hours in the refrigerator for cooling Minitube, in extenders Glycine Yolk Milk, Glycine purified Yolk Milk and Glycine Extract Milk and tested to exhaustion (37 ° C/240 min) were evaluated in vitro by means of computerized analysis of sperm kinetics, morphology and plasma membrane integrity. After 24 and 48 hours of refrigeration, the extenders Glycine purified Yolk Milk and Glycine Extract Milk showed better results than extender Glycine Yolk Milk, after the exhaustion test, for the parameter of membrane integrity. For the integrity of the acrosome through Glycine purified Yolk Milk was higher (P <0.05) than Glycine Yolk Milk during the exhaustion test. In other parameters of sperm kinetics and morphology, there were no significant differences (P> 0.05) among extenders. Between times, significant difference (P <0.05) in all extenders during the exhaustion test / Mestre

Master of Science / Department of Horticulture and Natural Resources / Eleni Pliakoni / Intensive specialty crop production within high tunnel systems in the central U.S. has greatly expanded. High tunnel systems, used primarily to protect specialty crops from harsh environmental conditions, improve marketability, and extend fruiting season. High tunnel day-neutral strawberry (Fragaria x ananassa) production in Kansas may by limited due to the high summer temperatures. Evaporative cooling within a high tunnel is a novel technique meant to cool the plant temperature during the hottest months of production. Currently, evaporative cooling is implemented in the early stages during the heavy bloom period. Spring-planted day-neutral strawberry production within high tunnels could provide growers with enhanced yields and marketability, improved storage quality, and late-season prices. This study identifies the optimum cultivars in a plasticulture, high tunnel system with the use of evaporative cooling in regards to yield, quality, storage life, and consumer opinion. The trial was conducted at the Kansas State University Olathe Horticulture Research and Extension Center (OHREC) during 2014 and 2015. Six commercially-available cultivars were evaluated: ‘Albion’, ‘Evie 2’, ‘Monterey’, ‘Portola’, ‘San Andreas’, and ‘Seascape’. Mature fruit (90-100% red) were harvested twice a week and four harvests were evaluated for at harvest and postharvest quality throughout each production year. Storage life was monitored every 24hrs by respiration rate, moisture content and overall visual quality, using a scale from 5 (excellent) to 1 (very poor). Physical and organoleptic quality measurements (texture and color, and soluble solids and titratable acidity) were evaluated every two days throughout storage, and nutritional quality (total phenolic and antioxidant availability) was evaluated at harvest. Our results indicate that ‘Portola’ had the highest yields in 2014 and 2015 at 1.33 lbs/plant and 1.12 lbs/plant, respectively. At harvest, the soluble solids content (°Brix) was highest with ‘Monterey’ and ‘Albion’ (P < 0.0001), while ‘San Andreas’, ‘Monterey’, ‘Portola’, and ‘Albion’ retained firm texture (force(g)) (P ≤ 0.0001). All cultivars maintained their overall visual quality until day 8, with the exception of ‘Evie 2’ and ‘Seascape’. Furthermore, the four cultivars maintained visual quality and had lower respiration rates and moisture content loss (P < 0.001, P < 0.0001, P < 0.05). Throughout storage, ‘Seascape’ had a high respiration rate (P < 0.0001) and low overall visual quality (P < 0.01). Moisture content loss (%) throughout 2014 storage life was less than in 2015 (P < 0.0001) and ‘San Andreas’ and ‘Monterey’ had the least moisture loss throughout both production seasons (P < 0.01). In our trials, evaporative cooling did not affect yield or the incidence of disease. However, the use of evaporative cooling resulted in lower total phenolic levels in both production years (P < 0.0001), and higher respiration rates during storage, as observed in 2015 (P ≤ 0.01). Because of significant year-to-year differences in berry weight (lbs/plant) and size (oz/fruit), further studies are needed to identify the weather effect and best management practices in the region. In Kansas, growing day-neutral strawberries in a high tunnel has potential based on yield and quality of the fruit that we evaluated.

Injection molding is one of the most common methods of mass production. After injecting molten plastic into a mold, the heat must leave the plastic material, enter the mold steel, enter the coolant, and exit the mold. This heat flow is critical to producing high quality parts rapidly. As plastic cools, the plastic shrinks. Uneven cooling causes uneven shrinkage which can cause the part to warp from the resulting internal stresses or create sink marks on the part. Thus the effect of uneven cooling is lower part quality, both in appearance and in dimension. Standard or conventional cooling channels are straight-drilled holes arranged such that they intersect and connect to form a loop for coolant, typically water, to flow through. This allows the mold to act as a heat exchanger, transferring heat to the coolant and carrying heated coolant away from the mold. While standard cooling channels have been used widely in the injection molding industry for their manufacturability and proven results, other methods have been developed for creating molds with cooling channels of any desired path or shape. These channels, called conformal due to how they conform to the shape of the part, provide uniform cooling, eliminate or reduce the quality issues of warpage and shrinkage, and provide faster, more economical cycle times. Conformal cooling is cannot be produced only by subtractive manufacturing methods that remove material from raw stock but rather through additive or hybrid manufacturing techniques that add material in layers of powder, sections, or sheets. Bonded sheet layer mold inserts can be made of any size and are currently the only feasible way of making large, conformally-cooled molds. Presented is a Six Sigma approach for implementing conformal cooling in existing molds to achieve the benefits of higher part quality and fast cycle times. Feasibility considerations include existing mold features such as slides and ejectors, choice of channel diameter, and the cooling channel path. Cost justification considerations include assessing part quality cost impact through calculation of the costs of poor quality and assessing machine capacity as relates to cycle time. With the approach presented, an injection molding company should be able to assess feasibility and cost effectiveness of implementing conformal cooling on its molds.

abstract: The concept of this thesis came up as a part of the efforts being devoted around the world to reduce energy consumption, CO2 emissions, global warming and ozone layer depletion. In the United States, HVAC units in residential buildings consumed about 350 billion kWh in 2017 [1],[2]. Although HVAC manufacturers are investing in new technologies and more efficient products to reduce energy consumption, there is still room for further improvement. One way of reducing cooling and heating energy in residential buildings is by allowing the centralized HVAC unit to supply conditioned air to only occupied portions of the house by applying smart HVAC zoning. According to the United States Energy Information Administration [3], the percentage of houses equipped with centralized HVAC units is over 70%, which makes this thesis applicable to the majority of houses in the United States. This thesis proposes to implement HVAC zoning in a smart way to eliminate all human errors, such as leaving the AC unit on all day, which turns out to be causing a serious amount of energy to be wasted. The total amount of energy that could be saved by implementing the concepts presented in this thesis in all single-family houses in the U.S. is estimated to be about 156 billion kWh annually. This amount of energy reduction is proportional to the electricity bills and the amount of dollars paid annually on energy that is technically being wasted. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2018