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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Odpružení kabiny nákladního vozidla / Truck Cabin Suspension

Hradský, Martin January 2019 (has links)
The diploma thesis, which belongs to the area of vehicle dynamics, deals with the issue of suspension of trucks cabins. In particular, it focuses on the suspension of a race truck cab such as the Rally Dakar. Includes an overview of truck suspension (especially cabs), driving comfort assessment methods and the impact of vibration on human. To verify the suitability of using different cab suspension concepts, a multibody model was built in program MSC ADAMS. Suitable primary suspension has been found appropriate for this model. Cab suspension was tested for driving safety, but first for driving comfort.
62

Parametric Analysis of Thermal Comfort and Energy Efficiency in a Building Located in Different Climate Regions

Patsatzis, Nikolaos January 2022 (has links)
One of the biggest challenges of a residential building, when it is designed, is to be energy efficient and to provide simultaneously many hours of thermal comfort throughout the year. So, this was the scope of this thesis: to perform a parametric analysis of thermal comfort and energy efficiency in a house that was designed for the climate of Gotland in Sweden. After that, modifications were introduced to the base model and each scenario was checked for the geographical locations of Thessaloniki, Greece and Barcelona, Spain, in order to decide what option is better. The modifications to the base model were changes in the structure of the external wall (insulation materials and total width), the insulation of the internal wall, the thermal bridges (set to good), the windows (3-pane glazing, schedule opening, external window shading, integrated shading), the installation of HVAC system, photovoltaics with efficiencies 15%, 17% and 22% and the introduction of chimney. Based on the results, the Gotland scenario that included the base model plus the modifications of the external and internal wall, HVAC system, PVs with 22% and external window shading increased the energy use by 18.7% but improved the thermal comfort as the yearly hours of dissatisfaction reduced to 22 from 882, compared to the base model. Similar results were taken from the case with the integrated shading in which the energy increased to 19.3%, but the hours of dissatisfaction declined to 24 throughout the year. Regarding only the energy cost of the house, the best location is Barcelona (without cooling). Nevertheless, when considering the overall thermal comfort, the best place for the house is Gotland, as the building was designed for the cold environment of Sweden and not the hot weather of the other southern cities.
63

Contact Comfort Initiated by the Nursery School Child

Spencer, Lana Kay 01 May 1969 (has links)
The study focused upon three aspects of child-initiated contact comfort situations; how ofter the contact was sought, with whom or why did the child seek comfort, and what incident seemed to stimulate the child's action. Data was collected from two Utah State University Nursery School Laboratories It was found that children respond as children in that similarity is greater than differences in utilization of contact comfort. Contact comfort is an important part of a child's functioning in social situations. The number of episodes to indicate this was substantial. The objects and persons to whom he turns for contact comfort vary within age and nature of the situation in which the child functions.
64

Use of physiological and perceptual dimensions of clothing comfort to evaluate nonwoven protective fabrics through wear testing of limited-use coveralls

Hennessey, Ann M. 12 November 1999 (has links)
The purpose of this research was to identify nonwoven protective fabrics designed to have improved comfort properties over a fabric currently used in limited-use chemical protective clothing by using physiological and perceptual dimensions of comfort. Fabrics that are both waterproof and breathable have potential for use in chemical protective clothing by repelling liquid while allowing the diffusion of moisture vapor from the body. Microporous laminated fabrics used in chemical protective clothing allow moisture to evaporate from the body and move through the fabric while preventing liquid chemicals from coming in contact with the skin. Five fabric types were evaluated by wear testing coveralls and measuring selected physiological and perceptual responses of five subjects performing moderate-intensity exercise in thermoneutral and hot, humid environments. Physiological responses included skin temperature, body temperature, heart rate, sweat rate, and fluid loss. Perceptual responses included moisture sensation, thermal sensation, Rating of Perceived Exertion, and overall comfort. In the thermoneutral environment, results show heart rate to be the only variable affected by the different fabric types, while time effect was significant within all dependent variables. In the hot, humid environment, skin and body temperatures were significantly affected by fabric type, while time effect was significant within all variables except skin temperature. The environment effect was significant within all dependent variables except RPE and heart rate. Based on the statistical insignificance of subjects' overall comfort responses in both environments, it can be said that the differences in the physical characteristics of the fabrics may not be great enough to affect the wearer's comfort level. However, two of the four fabrics were determined to have potential for further investigation. Further research comparing experimental fabrics with fabrics used widely in industry will continue the effort of improving the comfort of limited-use protective clothing. / Master of Science
65

Soundscape Evaluation on Mississippi State University Campus

Yildirim, Yalcin 13 December 2014 (has links)
The term soundscape, used for the first time at the end of 1970s, refers to the sum of the sounds that can be heard and perceived by people in a specific environment. The concept of soundscape has recently received attention in planning and design disciplines. Recent studies on soundscape have shown that the acoustic environment plays an important role for the comfort of site users. Hence, this research investigates how objective measurement of soundscape might be different from subjective perceptions of users in the Mississippi State University Campus as a public open space due to demographic and climatic variations. The public open spaces studied in the Mississippi State University Campus include four locations: the Mitchell Memorial Library, the Colvard Student Union, the Bell Island, and the Sanderson Center. These locations were evaluated through objective measurement, and subjective evaluation.
66

Methodology to Measure and Compare the Efficiency of Radiant Heaters Used in Poultry Brooding

Linhoss, John Emerson 12 August 2016 (has links)
During the first seven to ten days of life chicks are unable to maintain homeothermy, thus providing supplemental heat is critical to their livability and performance. Radiant heaters are the preferred method of providing heat during brooding because they provide a range of thermal comfort options for chicks. Infrared thermography is often used to assess the heat distribution created at the litter surface by radiant heaters. The resulting images provide a good qualitative assessment of heat distribution but do not provide any quantifiable metrics through which to compare the radiant output of heaters. Data acquisition systems were developed to measure the radiant flux emitted by six 11.72 kW radiant heaters and to determine radiant flux ranges preferred by broiler chicks during the first week of brooding. Results showed the radiant output was influenced by heater elevation above the litter and differed between manufacturers. 21 – 41% of the energy available the heaters was emitted to the litter as radiant heat. Chicks exhibited a decreasing preference for radiant flux with age. Maximum preferred radiant flux decreased from 387.0 W·m-2 at day 1 to 248.3 W·m-2 at day 8, while the minimum preferred radiant flux decreased from 61.2 W·m-2 at day 1 to 7.65 W·m-2 at day 8. Net usable area (NUA), or the total floor area within the range of radiant fluxes preferred by chicks, was calculated for each heater. Mean NUA by heater ranged from 45.34 (SE = 3.35 m2) to 21.75 (SE = 1.98 m2). Mean NUA significantly increased with heater mounting elevation (P < 0.0001). Results indicate that radiant heaters from different manufacturers with the same power output do not necessarily produce the same radiant distribution and that the maximum preferred radiant fluxes by chicks may not be realized at manufacturer specified heater mounting elevations.
67

Effects of Multi-Modal Warning Systems on Elderly Drivers'Perceived Urgency and Comfort

Ghosh, Arka Ashok 05 January 2006 (has links)
The objective of the study was to investigate multi-modality effects (visual and auditory) on the perception of urgency in elderly individuals addressing issues of safety and comfort. Twenty individuals (10 young, 10 elderly) from Montgomery County of Virginia participated in the laboratory study. In the pre-experimental audiometric tests, as expected elderly individuals had higher hearing thresholds (dBHL) than young across all the frequencies (250, 1000, 2000 and 4000 Hz) of pure tones. The difference was more pronounced at 4000 Hz. In visual acuity tests administered, elderly individuals had a lower Snellen VA than young at both near and far distances. The participants also were administered Bausch and Lomb color test; all participants were able to differentiate red color. Method of adjustment was used to collect empirical data. Rating test was administered after every treatment to objectively assess the participants' feeling of perceived urgency associated with the auditory warning signal. All the participants rated the experimental sound as urgent. Repeated measures was conducted to remove variations due to time and treatment conditions. A mixed-factorial design was used to investigate the main and interaction effects. The age effect was found to be marginally statistically significant. Modality and trial effects were not found to be significant. The reanalysis conducted after removal of outliers resulted in marginal statistical significance for age and modality main effects. Although not significant, a trend was seen in the pulse intensity levels (dBL) across modalities in the elderly individuals. Future research should be conducted to investigate modality effects in elderly individuals in a naturalistic driving environment which would give a better insight of the effects of dual modalities. / Master of Science
68

Desempenho térmico e visual de elementos transparentes frente à radiação solar / Thermal and visual performance of transparent elements related to the solar radiation

Santos, Joaquim Cesar Pizzutti dos 23 August 2002 (has links)
A especificação das vedações transparentes é uma das decisões mais complexas no âmbito do projeto arquitetônico. Envolve diversos fatores construtivos e de necessidades humanas relacionadas ao conforto ambiental, associadas a uma grande variedade de produtos disponíveis no mercado. Este trabalho busca facilitar aos projetistas esse processo de especificação, fornecendo valores dos parâmetros de desempenho dos elementos transparentes em relação à análise do conforto térmico e visual, coerentes com a realidade climática brasileira e com a real incidência da radiação solar ao longo do dia. Foram estudados os vidros comuns, laminados e refletivos, e as películas de controle solar, policarbonatos e acrílicos usados em edificações no Brasil. Foi utilizada a análise por espectrofotometria para a obtenção dos valores de refletância, transmitância a absortância para as diferentes regiões do espectro solar, com ângulos de incidência variados. A partir do relacionamento desses resultados, considerando o comportamento similar de variação do Fator do Calor Solar (FCS) e da Transmitância da Luz Visível (Tv) com o ângulo de incidência, foi desenvolvida uma metodologia que possibilita o cálculo simplificado de ganhos de calor e luz natural. / The specification of the transparent elements is one of the most complex decisions in the ambit of the architectural project. It involves several constructive factors and human necessities related to the environmental comfort, associated to a great variety of available products in the market. The aim of this work is to facilitate the specification process to the planners, supplying values of the performance parameters of the transparent elements in relation to the analysis of thermal and visual comfort, coherent with the Brazilian climatic reality and with real incidence of the solar radiation along of the day. It were studied the ordinary, laminate and reflective glasses, the solar control films, policarbonates and acrylic used in Brazilian constructions. The spectrophotometry analysis was used to obtain the reflectance, the transmittance and the absortance values for the different regions of the solar spectrum, with varied incidence angles. Starting from the relationship of those results, considering the similar behavior of variation of the Solar Heat Factor (FCS) and of Transmittance of the Visible Light (Tv) with the incidence angle, it was developed a methodology that facilitates the simplified calculation of heat and natural light gains.
69

Diretrizes projetuais para humanização hospitalar: Hospital de Clínicas da Universidade Federal do Triângulo Mineiro / Design guidelines for hospital humanization: teaching hospital of the Triângulo Mineiro Federal University

Garcia, Mariana Ferreira Martins 04 March 2016 (has links)
O Hospital de Clínicas da Universidade Federal do Triângulo Mineiro (HC UFTM) foi inaugurado em 1982 na cidade de Uberaba - MG e é, atualmente, o único hospital público do Triângulo Mineiro que oferece atendimento terceirizado de alta complexidade. Os critérios técnicos exigidos em normas rígidas para esses ambientes hospitalares dificultam o processo de humanização hospitalar como forma de atender os usuários satisfatoriamente e proporcionar espaços apropriados para o exercício dos profissionais da saúde e para auxiliar na cura dos pacientes. Sendo assim, o objetivo deste trabalho é propor diretrizes projetuais com a finalidade de melhorar o desempenho térmico e lumínico das alas de clínicas médica (CM) e cirúrgica (CC) do HC da UFTM. Para isso, a metodologia proposta consiste, inicialmente, num levantamento de dados dos aspectos projetuais e construtivos das alas estudadas. Posteriormente, foi feito um levantamento bioclimático de Uberaba dos últimos 10 anos junto a uma caracterização do edifício através dos cálculos das propriedades térmicas dos materiais e do uso das estratégias passivas no projeto. Para verificar a eficiência destas estratégias realizaram-se as análises dos métodos de Mahoney e Givoni. Além disso, o desempenho térmico e lumínico das alas de CM e CC foi analisado através das medições das temperaturas internas e externas, da umidade relativa do ar e dos níveis de iluminância. Depois, foram comparados com as recomendações de Mahoney e Givoni e à norma de iluminação NBR 8995-1. Os resultados encontrados indicaram que das estratégias passivas, a ventilação é a mais favorecida pela implantação do edifício, mas o resfriamento evaporativo e a alta inércia térmica não estão presentes. Além disso, os cálculos das 2 propriedades térmicas dos fechamentos verticais e horizontais e as medições das variáveis ambientais não apresentaram índices ideais de conforto e sim, altas transmitâncias, baixas inércias térmicas e, consequentemente, altas temperaturas no interior das alas, gerando um grande desconforto térmico praticamente o tempo todo. Além disso, os níveis de iluminância encontrados não estão adequados às normativas e, aliados a ambientes sem identidade visual desfavorecem ainda mais a percepção que os usuários/pacientes têm dos mesmos. Promover espaços ajardinados, melhorar o desempenho dos fechamentos através da utilização de isolantes térmicos e rever a concepção visual e os níveis mínimos de iluminação do HC são possibilidades eficientes e utilizadas em diversos hospitais para melhorar o conforto térmico e visual dos pacientes durante suas internações e assegurar qualidade no desempenho das tarefas dos funcionários. / In 1982, the teaching hospital (Hospital de Clínicas - HC) of the Triângulo Mineiro Federal University (UFTM) was opened in Uberaba, in Minas Gerais state in Brazil. Currently, it is the only public hospital in the Triângulo Mineiro area to offer third party high complexity services. Technical requirements in strict regulations for hospital environments make it harder to humanize them and satisfactorily assist users, provide health professionals with adequate working spaces and help the healing process. Therefore, this document aims to propose design guidelines to improve thermal and lighting performance in the medical clinic (clínica médica CM) and surgery clinic (clínica cirúrgica - CC) wings of the HC of UFTM. In order to achieve this, there was initially some data collection regarding design and building aspects related to the aforementioned hospital wings. Afterwards, it was necessary to gather data on the bioclimatic profile of Uberaba for the last ten years and relate it to the building using an estimate of the thermal properties of its materials and of the use of passive strategies in its design. To verify how effective the plans were, analyses based on Mahoney and Givonis methods were carried out. Furthermore, measurement of internal and external temperatures, of relative humidity and of illuminance levels were used to analyze thermal and visual performance of CM and CC wings. Then, the results were compared to Mahoney and Givonis recommendations and to lighting regulation NBR 8995-1. These results showed that regarding passive strategies, ventilation benefits the most from the building orientation, while evaporative cooling and high thermal inertia are absent. Moreover, thermal property figures of the vertical and the horizontal openings and measurements of environmental variables did 4 not present ideal comfort ratings, but high transmittance, low thermal inertia and, consequently, high temperatures inside the wings creating great thermal discomfort almost all the time. In addition, illuminance levels registered did not comply with regulations and, while associated with a lack of visual identity in rooms, caused users/patients to negatively perceive those rooms. Fostering green areas, improving insulation by using thermal insulation materials and revising the visual concept and the minimum illuminance levels in the HC are effective possibilities used in several hospitals to improve patients thermal and visual comfort while under treatment and to ensure quality to staff performance.
70

Estudo das variáveis do conforto térmico e luminoso em ambientes escolares /

Pizarro, Paula Roberta. January 2005 (has links)
Orientador: Léa Cristina Lucas de Souza / Banca: Nair Cristina Brondino / Banca: Lucila Chebel Labaki / Resumo: O desempenho do usuário em um ambiente está diretamente ligado às condições de conforto e estética oferecidas por aquele ambiente, inserindo-se no contexto dos estudos ergonômicos. Considerando-se espaços escolares, estas relações do usuário com o ambiente têm um caráter ainda mais importante, por refletir-se no próprio processo de aprendizado. É sob este aspecto que esta pesquisa se concentra, procurando estabelecer, qualificar e posteriormente quantificar variáveis que indiquem níveis de conforto ambiental para usuários de edificações escolares. É considerada a cidade de Bauru como área de estudo e dentro da linha ergonômica, visa estudar dois parâmetros de conforto ambiental especificamente: conforto térmico e conforto luminoso. Três escolas municipais são selecionadas e analisadas, definindo variáveis que abrangem três aspectos: pessoal, climático e constutivo. É feito um modelo de previsão de índice de satisfação térmica do usuário e de grau de iluminância de sala de aula. As importâncias relativas de cada variável são definidas através de testes de sensibilidade, valendo-se de redes neurais artificiais como ferramenta de modelação. / Abstract: The performance of users in an environment is directly related to the conditions of comfort and aesthetics offered by that environment, and it is part of the ergonomic studies field. Considering school environments, this relationship of the user with the environment is even more important, due to its influence in the learning process. This is the subject of this research, which establishes, qualifies and quantifies the variables that show the levels of environmental comfort for school users. The case study is the city of Bauru, and from the ergonomic point of view, two parameters of the environmental comfort are considered: thermal comfort and lighting comfort. Three public schools of the municipality are selected and analyzed for the determination of variables that incoude three aspects: personal, climatic and constructive. A prediction model is developed in order to simulate the level of user's satisfaction. The relative importance of each variable is determined by sensitivity tests using artificial neural network modeling tools. / Mestre

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