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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.
1

Emergency Preparedness in Utah Households with Emphasis on Water and Food Storage Conditions

Gerla, Stephanie Rae 15 March 2013 (has links) (PDF)
Emergency preparedness steps taken by individuals in Utah households were evaluated in 3 studies. Study 1 evaluated the 2011 landline and cell phone Behavioral Risk Factor Surveillance System Survey and General Preparedness Optional Module results from two states, Louisiana and Utah, to find factors from demographic and medical data that can be used to predict emergency preparedness in individuals. Stepwise logistical regression analysis ascertained the ability of chosen variables to predict individuals' preparedness. The rate of prepared individuals was lower if they were between the ages of 18 to 54 years, when compared to the reference age group of 65 or older. Also, the rate of prepared participants was lower if they were female, had children under age 18 at home, or were unable to afford a doctor in the past year. Rate of prepared respondents was higher if they owned a home or were married (p <0.05). Study 2 evaluated water stored for emergency purposes in households throughout Utah for coliform, E. coli, free chlorine, and antimony. Ninety one percent of the stored water samples were found to be safe for human consumption. However, 9% of water samples were not considered safe due to over chlorination or the presence of coliform. Of 240 samples, 7 contained coliform and 14 samples had total chlorine levels over the Environmental Protection Agency's 4 ppm limit. Water in clear, polyethylene terephthalate soda bottles, even when stored for >18 months, did not exceed 0.3 ppb antimony, a level significantly lower than the Environmental Protection Agency limit of 6.0 ppb antimony. Study 3 measured for one year the temperature and humidity of food storage areas in 67 households within Utah. In 63% of locations, temperatures exceeded 24 °C, which can be considered abusive for food storage. The maximum temperature reached in a food storage area was 37.9 °C. Percent relative humidity exceeded 60% in 43% of food storage areas, which can be considered abusive for food stored in packaging permeable to moisture. The maximum percent relative humidity reached was 92.5%. In conclusion, most water stored for emergency purposes was considered safe, but temperature and humidity conditions for most food storage areas exceeded recommended maximums, and emergency preparedness of households within Utah needs to be improved.
2

Experimental and CFD Evaluation of Humidity Management Methods of Ruggedizing a COTS Electronics System for a Severe Climatic Environment

ZHANG, YAFAN January 2007 (has links)
This master thesis is about an investigation of anti-moisture methods for a nonhermeticelectronics enclosure containing a number of printed circuit boards(PCB) and placed in a severe climatic environment. The relevant theoretical background was provided first. It included the impact of moisture on electronics, some useful psychrometrics concepts, heat transfer fundamentals, introduction of environmental test, temperature and humiditysensing techniques, computational fluid dynamics (CFD) modelling, antimoisture methods and commercial heaters in the current marketing. Then a CFD modelling methodology was developed and validated based on experiment data. An extra heater was added to the enclosure to prevent water adsorption on printed circuit assemblies (PCA) surfaces. The heat dissipation and switch-on period strategies were parametrically studied in order to maintain the internal relative humidity below 60% in the vicinity of PCA surfaces, according to the relative humidity control method. In the end, results obtained from the environmental tests and the CFD simulations were presented and analyzed. Conclusions and future work were also discussed.
3

Experimental and CFD Evaluation of Humidity Management Methods of Ruggedizing a COTS Electronics System for a Severe Climatic Environment

ZHANG, YAFAN January 2007 (has links)
<p><p>This master thesis is about an investigation of anti-moisture methods for a nonhermeticelectronics enclosure containing a number of printed circuit boards(PCB) and placed in a severe climatic environment.</p><p>The relevant theoretical background was provided first. It included the impact of moisture on electronics, some useful psychrometrics concepts, heat transfer fundamentals, introduction of environmental test, temperature and humiditysensing techniques, computational fluid dynamics (CFD) modelling, antimoisture methods and commercial heaters in the current marketing.</p><p>Then a CFD modelling methodology was developed and validated based on experiment data. An extra heater was added to the enclosure to prevent water adsorption on printed circuit assemblies (PCA) surfaces. The heat dissipation and switch-on period strategies were parametrically studied in order to maintain the internal relative humidity below 60% in the vicinity of PCA surfaces, according to the relative humidity control method.</p><p>In the end, results obtained from the environmental tests and the CFD simulations were presented and analyzed. Conclusions and future work were also discussed.</p></p>
4

Armazenamento de sementes de craibeira (Tabebuia aurea (Silva Manso) Benth & Hook. F. ex S. Moore) / Storage of craibeira (Tabebuia aurea (Silva Manso) Benth. & Hook. F. ex. S. Moore) seeds.

BARBOSA, Mozart Duarte 21 June 2004 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-09-01T12:08:17Z No. of bitstreams: 1 Mozart Duarte Barbosa (1).pdf: 425228 bytes, checksum: 4f1c3a3dc00c3049007e624b85aea247 (MD5) / Made available in DSpace on 2016-09-01T12:08:17Z (GMT). No. of bitstreams: 1 Mozart Duarte Barbosa (1).pdf: 425228 bytes, checksum: 4f1c3a3dc00c3049007e624b85aea247 (MD5) Previous issue date: 2004-06-21 / This work aimed to evaluate the conservation of the seeds of the craibeira (Tabebuia aurea (Silva Manso) Benth. & Hook. F. ex. S. Moore) in differents storage environment and packings. The craibeira seeds were collected from 20 trees located in the metropolitan area of city of Recife-PE. After the collection, seeds were submitted to selection and homogenization. The seeds of water 14,94% were conditioned in the packings Kraft paper bag, poliethylene bag and metal recipient in stored under environmental laboratory (25,68 °C and 63,83%), refrigerator (5,08 °C and 48,70%) and dry cold (20,48 and 41,73%) during nine month period. The experiment was completely ramdom, with 4 repetitions of 25 seeds. The physiologic quality of the seeds was evaluated at the beginning and at every 30 days of storage, through the germination and vigor (index of germination speed (IVG) and root length) determinate seed moisture content. The results showed that the seeds present the largest germination averages and vigor when conditioned in Kraft paper bag or metal recipient, in the dry cold / O presente trabalho teve como objetivo avaliar a conservação de sementes de craibeira (Tabebuia aurea) em diferentes ambientes de armazenamento e embalagens. As sementes de craibeira, oriundas de 20 árvores localizadas na região metropolitana do Recife-PE, após a coleta, foram submetidas à seleção e homogenização. Estas com 14,94% de água foram acondicionadas nas embalagens saco de papel Kraft, saco de polietileno e em recipiente metálico, em ambiente natural de laboratório (25,68°C e 63,83% UR), geladeira (5,08°C e 48,70 % UR) e em câmara seca (20,48°C e 41,73% UR) durante nove meses. O experimento foi instalado em delineamento inteiramente casualizado, em esquema de parcelas subdivididas, com 4 repetições de 25 sementes. A qualidade fisiológica das sementes foi avaliada no início e a cada 30 dias de armazenamento, através da germinação, vigor (índice de velocidade de germinação (IVG) e comprimento de raiz) determinando-se também o teor de água das sementes. Os resultados permitiram concluir que as sementes apresentaram as maiores médias de germinação e vigor quando foram acondicionadas em embalagens de papel Kraft ou em recipiente metálico, em ambiente de câmara seca

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