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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.
141

Assessment of indoor air quality in Texas elementary schools

Sanders, Mark Daniel, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
142

Inhalation exposure pathways for polybrominated diphenyl ethers a source to human receptor model for semivolatile organic compounds /

Waye, Scot Kenyon, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
143

Dica visual e desempenho do chute no futsal : efeito do tempo para tomada de decisão e da fadiga /

Baptista, André Macari. January 2017 (has links)
Orientador: Fabio Augusto Barbieri / Banca: Sergio Augusto Cunha / Banca: Sergio Tosi Rodrigues / Resumo: O futsal é um esporte de alta intensidade e intermitente que tem como principal ação na tentativa de fazer gol o chute, porém não se sabe como ocorre a interação entre o goleiro e o batedor. Portanto, entender o mecanismo de percepção-ação sob efeito da fadiga durante o chute utilizando a estratégia de goleiro-dependente é de grande relevância para o esporte. Assim os objetivos do estudo são: a) verificar a influência de diferentes momentos de inserção da dica visual durante a corrida de aproximação no comportamento motor e do olhar no desempenho do chute com a bola parada no futsal; b) investigar o efeito da fadiga no comportamento do olhar e na precisão durante o chute com a bola parada no futsal de acordo com a manipulação da dica visual. Do estudo 1, participaram 17 atletas amadores que realizaram 18 chutes com bola parada em 3 condições (dica visual a 1,6 e 0,8 metros da corrida de aproximação pra bola e sem dica visual). Para verificar os parâmetros motores, visuais e desempenho foram utilizados sistemas de câmeras infravermelho (OptiTrack 17W) e de rastreamento do olho (EyeTracking Mobile System). As condições foram comparadas por meio de ANOVA one way e análise de magnitude de efeito. Houve somente diminuição na velocidade do último passo na condição de dica visual a 0,8 metros comparado com a 1,6 metros (p = 0,042). A análise de magnitude de efeito revelou pequenos possíveis aumento na atenção e diminuição na velocidade do movimento na condição sem dica visual e dica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Futsal is a high-intensity and intermittent sport that has as main action in the attempt to make goal kick, but it isn't known how the interaction between the goalkeeper ante the bater occurs. Therefore, to understand the mechanism of perception-action under the effect of fatigue during the kick using the goalkeeper-dependent strategy is of great relevance for the sport. Thus the aims of the study are: a) To verify the influence of different moments of insertion of the visual tip during the approach run in the motor behavior and visual control in the performance of the kick with stationary ball in futsal; b) To investigate the effect of fatigue in the visual behavior and the precision during the kick with stationary ball in futsal according to the manipulation of the visual tip. From Study 1, 17 amateur athletes participated in 18 kicks stationary ball in 3 conditions (visual tip at 1.6 a 0.8 meters from the approach run to the ball and without visual tip). To verify the motor, visual and performance parameters were used infrared camera systems (OptiTrack 17W) and eye tracking (EyeTracking Mobile System). The conditions was compared using ANOVA one way and effect magnitude analysis. There was only a decrease in velocity of the last step in the visual tip condition at 0.8 meters compared to 1.6 meters (p = 0.042). The analysis of magnitude of effect revealed small possible increase in attention and decrease in movement speed in the condition without visual tip and visual t... (Complete abstract click electronic access below) / Mestre
144

Návrh podnikové strategie společnosti JC STAV s.r.o.

Hlaváčová, Miroslava January 2011 (has links)
No description available.
145

Effects of low humidity on comfort, health, and indoor environmental quality: literature review

Hamehkasi, Maryam January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Melanie M. Derby / Ronaldo G. Maghirang / This study was conducted to investigate the effects of humidity on comfort, health, and indoor environment quality (IEQ) using a comprehensive literature review. Published papers were obtained from keyword and citation searches from bibliographic databases (i.e., PubMed, Scopus, and Google Scholar), including papers from 1985 to 2015. Over 600 papers were identified and classified based on topic area; from these papers, seven were chosen as case studies for this report. The seven papers represent studies on various topics, including bacteria, influenza/virus transmission, elderly subjects, indoor air quality, effects on eyes and skin, dust mites, and asthma. Theunissen et al. (1993) showed bacteria (gram positive and gram negative) do not act the same in low or high humidity conditions. Lowen et al. (2007) studied influenza transmission. Sunwoo et al. (2006) used elderly subjects to study eyes, skin, and comfort. Reinikianen et al. (1992) and Nordström et al. (1994) surveyed a large number of subjects, controlled humidity, and assessed multiple factors regarding indoor health and comfort. Arlian et al. (2001) implemented dehumidifier as a way to reduce house dust mites. Kaminsky et al. (1995) tested asthmatic subjects and healthy subjects to compare the effects of dry air on asthma. From these case studies low humidity appeared to have a variety of effects on health and comfort; however, no precise and defined borderline exists to distinguish acceptable low humidity. Acceptable low humidity levels depend on many factors, including building location and purpose, age of occupants, and climatic conditions.
146

An Energy Audit of Kindergarten Building in Vallbacksgården

Liu, Xiaojing, Zhang, Taoju January 2015 (has links)
Energy consumption rises continuously every year. Globally, buildings count for half of electricity consumption and 20%-40% of total energy consumption. Building energy sector consumed 40% of total energy use in Sweden. The vital of reduce energy consumption is to enhance building efficiency. This energy audit work investigates how energy consumes of kindergarten building in Vallbacksgården. Then give out cost effective suggestions to improve energy efficiency for object building. The result shows total amount of energy input of the building is equal to 241.9 MWh. While district heating takes the largest part of energy input that correspond to 188.9 MWh (78%), and cost around 123500 Kr annually. Furthermore, energy 38.0 MWh (16%) is contributed by solar radiation, which becomes second largest source of energy input. Finally, internal heat generation is the smallest contributor of energy input which counts 15.0 MWh (6%). For energy output, majority of heat loss is leaded by transmission losses. It cost 190.4 MWh per year that shares 79% of total energy output. Nature ventilation losses of object building shares 17% of total heat output which is 41.7 MWh. Mechanical ventilation and hot tap water have energy consumption with 7.8 MWh and 2.0 MWh respectively. They take rest 4% of total energy output. According to the finding, several reasonable suggestions will be given. Firstly, for the costless solution, decreasing indoor temperature 1℃ or 2 ℃ is able to reduce heating demand 9.0 MWh or 18.1 MWh annually. It will reduce CO2 emission 131859g- 266070 g, and save 5274 – 10642 SEK per year. Secondly, substitute district heating systems by ground source heat pump is an environmental solution. Using ground source heat pump has priority of environment, which lower CO2 emission 1909200 g/year and save 68262 SEK/year by analyze. Investment for this solution is 979000 SEK and the payback time takes 14.3 year. Replace old windows is a moderate solution of cost. Substitution by using energy glass can reduce 20.9 MWh heating demand and 307377 g CO2 every year. New energy glass windows can cut 13591 SEK for district heating every year. The renovate investment and payback time are more than 159732 SEK and 11.8 year respectively.
147

Minimum Euclidean Distance Algorithm for Indoor WiFi Received Signal Strength (RSS) Fingerprinting

Zegeye, Wondimu K., Amsalu, Seifemichael B. 11 1900 (has links)
While WiFi-based indoor localization is attractive, the need for a significant degree of pre-deployment effort is a key challenge. In this paper, indoor localization with no pre-deployment effort in an indoor space, such as an office building corridor, with WiFi coverage but no apriori knowledge of the placement of the access points(APs) is implemented for mobile devices. WiFi Received Signal Strength(RSS) in the considered environment is used to build radio maps using WiFi fingerprinting approach. Two architectures are developed based on this localization algorithm. The first one involves a client-server approach where the localization algorithm runs on the server whereas the second one is a standalone architecture and the algorithm runs on the SD card of the mobile device.
148

Active scene illumination metods for privacy-preserving indoor occupant localization

Zhao, Jinyuan 29 September 2019 (has links)
Indoor occupant localization is a key component of location-based smart-space applications. Such applications are expected to save energy and provide productivity gains and health benefits. Many traditional camera-based indoor localization systems use visual information to detect and analyze the states of room occupants. These systems, however, may not be acceptable in privacy-sensitive scenarios since high-resolution images may reveal room and occupant details to eavesdroppers. To address visual privacy concerns, approaches have been developed using extremely-low-resolution light sensors, which provide limited visual information and preserve privacy even if hacked. These systems preserve visual privacy and are reasonably accurate, but they fail in the presence of noise and ambient light changes. This dissertation focuses on two-dimensional localization of an occupant on the floor plane, where three goals are considered in the development of an indoor localization system: accuracy, robustness and visual privacy preservation. Unlike techniques that preserve user privacy by degrading full-resolution data, this dissertation focuses on an array of single-pixel light sensors. Furthermore, to make the system robust to noise, ambient light changes and sensor failures, the scene is actively illuminated by modulating an array of LED light sources, which allows algorithms to use light transported from sources to sensors (described as light transport matrix) instead of raw sensor readings. Finally, to assure accurate localization, both principled model-based algorithms and learning-based approaches via active scene illumination are proposed. In the proposed model-based algorithm, the appearance of an object is modeled as a change in floor reflectivity in some area. A ridge regression algorithm is developed to estimate the change of floor reflectivity from change in the light transport matrix caused by appearance of the object. The region of largest reflectivity change identifies object location. Experimental validation demonstrates that the proposed algorithm can accurately localize both flat objects and human occupants, and is robust to noise, illumination changes and sensor failures. In addition, a sensor design using aperture grids is proposed which further improves localization accuracy. As for learning-based approaches, this dissertation proposes a convolutional neural network, which reshapes the input light transport matrix to take advantage of spatial correlations between sensors. As a result, the proposed network can accurately localize human occupants in both simulations and the real testbed with a small number of training samples. Moreover, unlike model-based approaches, the proposed network does not require modeling assumptions or knowledge of room, sources and sensors.
149

Comparison between three different CFD software and numerical simulation of an ambulance hall

Li, Ning January 2015 (has links)
Ambulance hall is a significant station during emergency treatment. Patients need to be transferred from ambulance cars to the hospital’s building in the hall. Eligible performance of ventilation system to supply satisfied thermal comfort and healthy indoor air quality is very important. Computational fluid dynamic (CFD) simulation as a broadly applied technology for predicting fluid flow distribution has been implemented in this project. There has two objectives for the project. The first objective is to make comparison between the three CFD software which consists of ANSYS Fluent, Star-CCM+ and IESVE Mcroflo according to CFD modeling of the baseline model. And the second objective is to build CFD modeling for cases with difference boundary conditions to verify the designed ventilation system performance of the ambulance hall. In terms of simulation results from the three baseline models, ANSYS Fluent is conclusively recommended for CFD modeling of complicated indoor fluid environment compared with Star-CCM+ and IESVE Microflo. Regarding to the second objective, simulation results of case 2 and case 3 have shown the designed ventilation system for the ambulance hall satisfied thermal comfort level which regulated by ASHRAE standard with closed gates. Nevertheless, threshold limit value of the contaminants concentration which regulated by ASHRAE IAQ Standard cannot be achieved. From simulation results of case 4.1 to 4.3 shown that the designed ventilation system cannot satisfy indoor thermal comfort level when the gates of the ambulance hall opened in winter. In conclusion, measures for decreasing contaminants concentration and increasing indoor air temperature demanded to be considered in further design.
150

The Role of Clothing Fabrics as Passive Pollen Collectors in the North-Eastern United States

Zavada, Michael S., McGraw, Stephanie M., Miller, Melissa A. 01 December 2007 (has links)
The purpose of this investigation is to determine if clothing fabrics act as passive pollen collectors, and to determine if different fabrics vary with regard to the abundance and type of pollen trapped. Five of the most common fabrics in the United States (cotton, wool, polyester, silk and linen) were used to trap pollen. The pollen collecting apparatus was constructed of a 30 cm diameter circular needlepoint hoop, which vertically rotated freely, and was mounted on a dowel that was driven into the soil to chest height. Five pollen collectors, each with one of the five fabrics were placed at a collection site in rural, suburban, and urban habitats in Rhode Island for a 24 h period at weekly or biweekly intervals throughout 2002-2003. Pollen was washed from each of the fabrics and acetolysed. Total pollen per cm2 removed from each of the fabric types was estimated using a haemocytometer. The pollen types were identified, and 200 grains were counted to determine the relative abundance of the various pollen types recovered from the fabrics. Clothing fabrics act as passive pollen collectors and the flora recovered from the fabric represent the qualitative and quantitative components of the pollen rain for that specific day. There are quantitative differences among the relative abundance of pollen types from the three habitats (urban, suburban, and rural). Washing with water and a detergent eliminates a majority of the pollen from the fabrics.

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