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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.
221

O clima urbano de Pirapozinho – SP: eventos de ilhas de calor urbanas em episódios de verão / The urban climate of Pirapozinho – SP: events of urban heat islands in summer episodes

Silva, Liliane Pimentel da [UNESP] 16 January 2017 (has links)
Submitted by LILIANE PIMENTEL DA SILVA null (lilinhapsilva@yahoo.com.br) on 2017-02-09T00:15:43Z No. of bitstreams: 1 Dissertação.Liliane.pdf: 7831185 bytes, checksum: 8781451a3c7a43904e560ea59ec0c552 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-13T17:30:53Z (GMT) No. of bitstreams: 1 silva_lp_me_prud.pdf: 7831185 bytes, checksum: 8781451a3c7a43904e560ea59ec0c552 (MD5) / Made available in DSpace on 2017-02-13T17:30:53Z (GMT). No. of bitstreams: 1 silva_lp_me_prud.pdf: 7831185 bytes, checksum: 8781451a3c7a43904e560ea59ec0c552 (MD5) Previous issue date: 2017-01-16 / As cidades pequenas desempenham um papel relevante no território nacional, pois são numerosas e apresentam problemas ambientais, mesmo que em menor magnitude quando se compara às grandes cidades. O estudo do clima urbano em cidades de pequeno porte tem crescido, devido à necessidade de se entender a dinâmica climática em locais com menor expressividade territorial e com possibilidade de ter um crescimento urbano mais bem planejado. Nesse sentido, analisou-se o clima urbano de Pirapozinho/SP, município localizado no extremo oeste paulista, pertencente à microrregião de Presidente Prudente/SP. Pirapozinho tem aproximadamente 25 mil habitantes e uma área urbana com construções horizontais e com atividades econômicas diversificadas: comércio, serviços e indústrias. Desta forma, o principal objetivo deste trabalho foi analisar a temperatura e a umidade do ar no espaço urbano e entorno rural próximo para se diagnosticar a geração do clima urbano em Pirapozinho/SP, como resultado da produção espacial da cidade. Para tanto, foram realizadas análises da temperatura e umidade relativa do ar, registradas em pontos fixos e transectos móveis, no intraurbano e rural próximo nos meses de dezembro de 2014 e janeiro de 2015. Para subsidiar a escolha dos pontos e a análise dos resultados foram utilizados mapas de ocupação e uso da terra e das características do relevo. Os registros de temperatura do ar dos transectos móveis realizados no período noturno, no mês de janeiro de 2015, teve como finalidade elaborar um mapa de modelagem da temperatura, a partir do suporte oferecido pelas imagens do satélite LANDSAT 8 (bandas 3, 4 e 5). Além disso, foram elaboradas cartas de temperaturas da superfície, utilizando-se de imagens do satélite LANDSAT 8 (banda 10). Pirapozinho apresentou diferenças térmicas e de umidade relativa do ar entre a área urbana e a área rural, caracterizando as ilhas de calor, em sua maioria, de média magnitude, entre 2° C e 4° C. / Small cities perform a relevant role in the national territory, because they are numerous and present environmental problems, even if to a lesser magnitude when compared to large cities. The study of the urban climate in small cities has grown due to the necessity to understand the climatic dynamics in places with less territorial expressiveness and with the possibility of having a better planned urban growth. In this sense, it hás been analyzed the urban climate of Pirapozinho / SP, a municipality located in the extreme west of São Paulo, belonging to the microregion of Presidente Prudente / SP. In Pirapozinho,there are approximately 25 thousand inhabitants and an urban area with horizontal constructions and diversified economic activities: commerce, services and industries. In this way, the main objective of this work was to analyze the temperature and humidity of the air in the urban space and nearby rural surroundings to diagnose the generation of the urban climate in Pirapozinho / SP, as a result of the spatial production of the city. For that, analyzes of the temperature and relative humidity of the air recorded in fixed points and mobile transects were carried out in the intraurban and near rural areas in the months of December 2014 and January of 2015. In order to subsidize the choice of points and the analysis of the results, occupation maps , land use and relief characteristics were used. The air temperature records of the mobile transects performed in the night period, in January of 2015, had the purpose of elaborating a temperature modeling map, from the support provided by the Landsat 8 satellite images (bands 3, 4 and 5 ). In addition, charts of surface temperatures were made by using images from the Landsat 8 satellite (band 10). Pirapozinho presented thermal and relative humidity differences between the urban area and the rural area, characterizing the islands of heat, mostly of medium magnitude, between 2 ° C and 4 ° C.
222

Montagem e instalaÃÃo de um sistema de controle automÃtico de irrigaÃÃo / Assembly and installation of a system of automatic control of irrigation

Wlisses Matos Maciel 01 March 2005 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Este trabalho teve como objetivos montar e instalar sistemas de irrigaÃÃo com diferentes nÃveis de automaÃÃo: automÃtico inteligente, automÃtico por temporizador e nÃo automÃtico. Foi conduzido um experimento na Ãrea experimental do LaboratÃrio de HidrÃulica e IrrigaÃÃo da Universidade Federal do CearÃ, em Fortaleza, CE, no perÃodo de outubro de 2004 a janeiro de 2005. Esses trÃs sistemas foram distribuÃdos em um delineamento estatÃstico em blocos casualizados. O delineamento constou de 6 blocos e trÃs tratamentos distribuÃdos em 18 parcelas experimentais medindo 4m de largura e 12m de comprimento, ocupando uma Ãrea total de 1600m2. A montagem foi dividida em duas fases, a primeira fase consistiu na montagem dos sistemas eletrÃnico e elÃtrico composto por sensores de umidade (blocos de resistÃncia), sensores de temperatura (termopares), datalogger, multiplexador, placa digital de E/S padrÃo ISA, placa condicionadora de relÃs, temporizador, contactores, relÃs, chave de partida, cabeamento, aterramento e a segunda dos sistemas hidrÃulico e de irrigaÃÃo composto de bombas, tubulaÃÃes, reservatÃrios, manÃmetros, hidrÃmetros, venturis, tomadas de pressÃo e conexÃes; todos os sistemas preconizados foram montados e instalado no campo. / This work had as objectives to set up and to install overhead irrigations with different automation levels: automatic intelligent, automatic for temporizador and no automatic. An experiment was driven in the experimental area of the Laboratory of Hydraulics and Irrigation of the Federal University of CearÃ, in Fortaleza, CE, in the period of October of 2004 to January of 2005. Those three systems were distributed in a statistical delineamento in blocks casualizados. The delineamento consisted of 6 blocks and three treatments distributed in 18 experimental portions measuring 4m of width and 12m of length, occupying a total area of 1600m2. The assembly was divided in two phases, the first phase consisted of the assembly of the electronic and electric systems composed for sensor of humidity (resistance blocks), sensor of temperature (termopares), datalogger, multiplexador, digital plate of E/S pattern ISA, conditioning plate of relÃs, temporizador, contactores, relÃs, departure key, cabeamento, aterramento and Monday of the waterworks and of irrigation composed of bombs, piping, reservoirs, manÃmetros, hydrometers, venturis, pressure sockets and connections; all of the extolled systems were mounted and installed in the field.
223

Desenvolvimento de um tensiÃmetro eletrÃnico para o monitoramento do potencial da Ãgua no solo / Electronic development of a tensiometer for the monitoring of the potential of the water in the soil

Silvana de Lourdes Coelho 21 February 2003 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O presente trabalho apresenta o desenvolvimento, calibraÃÃo e testes de um tensiÃmetro de leitura eletrÃnica. O dispositivo foi calibrado utilizando como padrÃo de comparaÃÃo o tensiÃmetro de mercÃrio, e testado quanto ao tempo de resposta, efeito de flutuaÃÃes diurnas de temperatura nas leituras de potenciais, sensibilidade e precisÃo. Os ensaios foram conduzidos no LaboratÃrio de MecÃnica e EletrÃnica do Departamento de Engenharia AgrÃcola da UFC. A bancada de ensaio constituiu-se de trÃs caixas plÃsticas preenchidas com solo de densidade 1,4 g.cm3 e textura franco arenosa. Para o desenvolvimento dos testes, nove tensiÃmetros eletrÃnicos e trÃs tensiÃmetros de mercÃrio foram instalados. O tensiÃmetro eletrÃnico difere do tensiÃmetro de mercÃrio por substituir o mercÃrio como manÃmetro de pressÃo por um sensor de pressÃo, disposto em um circuito eletrÃnico juntamente com um sensor de temperatura, o qual foi calibrado antes da instalaÃÃo. O sistema de aquisiÃÃo de dados constituiu-se de um conversor analÃgico/digital, de 12 bits, microcontrolador e microcomputador portÃtil. Durante o perÃodo de um mÃs, foram coletados dados utilizados para gerar equaÃÃes de calibraÃÃo do tipo C = offset + bψ m , onde C à o valor do contador (cont) enviado ao computador e Ψm à o valor de potencial fornecido pelo tensiÃmetro de mercÃrio. Os valores mÃximo e mÃnimo de offset foram de 348,572 e 261,026, respectivamente, e de coeficiente angular de 3,597 e 3,376, respectivamente. Os resultados obtidos para o ajuste de regressÃo linear simplesindicaram a existÃncia de regressÃo a 1% de significÃncia e os coeficientes de correlaÃÃo apresentaram valores nunca inferiores a 0,9994. Para validar as equaÃÃes de calibraÃÃo, deu-se inÃcio a um segundo ciclo de secagem, entre as datas de 01/11/2002 a 13/12/2002, onde se obteve um valor de 0,9957 para o coeficiente de correlaÃÃo mÃnimo entre valores observados e esperados. O desvio entre os valores observados e os esperados deve-se provavelmente ao solo ainda estar passando por processos de agregaÃÃo e/ou estruturaÃÃo. As cÃpsulas porosas foram testadas quanto à condutÃncia e pressÃo de borbulhamento, apresentando valores mÃdios de condutÃncia igual de 2,031x10-3 cm2.s-1 e mÃnimo para pressÃo de borbulhamento de 1,3 atm. Quanto aos testes realizados no tensiÃmetro eletrÃnico, conclui-se que ocorre um aumento do tempo de resposta do equipamento com a diminuiÃÃo no potencial do solo, sendo este o principal fator de modificaÃÃo da resposta dos tensiÃmetros testados. Conclui-se ainda, que o erro nas leituras, decorrentes das flutuaÃÃes diurnas de temperatura, à evidente, principalmente nas horas em que o equipamento registra as maiores temperaturas, e a medida em que os potenciais diminuem. Os trÃs dispositivos testados apresentaram sensibilidades de 42,763, 42,575 e 43.161 mV.kPa-1, e precisÃo de 0,02338 (0,2385), 0,02348 (0,2394) e 0,02317 (0,2362) kPa (cm.c.H2O).
224

Otimização da malha de cogeração de energia em usina de açúcar e álcool. / Optimization of the energy cogeration loop in sugarcane plants.

Giancarlo Cittadino 22 February 2017 (has links)
A matriz elétrica brasileira é baseada em energias renováveis e principalmente, na energia hidráulica. Frente a algumas crises que o país viveu, faz-se necessário encontrar fontes alternativas de produção de energia elétrica que possam auxiliar a principal fonte energética, principalmente no período de estiagem. A biomassa é uma alternativa viável de combustível para a produção de eletricidade através de centrais de geração e cogeração de energia. Dentre as alternativas para a produção de eletricidade, temos as usinas de açúcar e álcool, que possuem um grande potencial de produção energética, que pode ser otimizado através do melhor aproveitamento da queima de bagaço. Esta dissertação estuda todos os elementos de cogeração de energia em usinas sucroalcooleiras, com ênfase no bagaço e na caldeira, propondo uma alternativa para aperfeiçoar a eficiência da queima do bagaço. Esta proposição é por meio da utilização de medidores de vazão e umidade do bagaço, aliado a um controlador lógico que atue sobre as entradas da cogeração de energia, para aumentar a eficiência da malha e diminuir o desperdício das variáveis de entrada. Todas as proposições são simuladas com dados de uma usina de açúcar e álcool, para que seja possível validar o modelo, e comprovar os ganhos provenientes da utilização do controlador. Através deste controlador, verificou-se que a usina queima mais bagaço que o necessário, diminuindo o rendimento da caldeira e perturbando o restante do processo. / The Brazilian electrical energy matrix is based on renewable energies mainly on hydroelectric energy. As the country has experienced some energy crisis, it is necessary to find alternative sources of electric energy production that can help to keep the offer of the main energy source, especially during the dry season. Biomass is a viable alternative fuel for the production of electricity, through generation power plants and cogeneration power plants. Among electricity production alternatives, we have the sugar and alcohol plants, which have a great energy production potential that which can be optimized through the best use of bagasse burning. This dissertation will study all the elements of energy cogeneration in sugarcane plants, by emphasizing bagasse and boiler, proposing an alternative to improve bagasse burning efficiency. This proposition will be proven through the use of flow meters and bagasse moisture, together with a logic controller that acts on the inputs of the energy cogeneration, which increase the efficiency of the mesh and reduce the wastage of the input variables. All propositions will be simulated with data from a sugar and alcohol mill, so that it is possible to validate the model, and to prove the gains from using the controller. Through this controller, it was verified that the plant burns more bagasse than necessary, reducing the efficiency of the boiler and disturbing the rest of the process.
225

Thermodynamic processes involved in wave energy extraction

Medina-López, Encarnación January 2018 (has links)
Wave energy is one of the most promising renewable energy sources for future exploitation. This thesis focuses on thermodynamic effects within Oscillating Water Column (OWC) devices equipped withWells turbines, particularly humidity effects. Previous theoretical studies of the operation of OWCs have resulted in expressions for the oscillation of the water surface in the chamber of an OWC based on linear wave theory, and the air expansion{compression cycle inside the air chamber based on ideal gas theory. Although in practice high humidity levels occur in OWC devices open to the sea, the influence of atmospheric conditions such as temperature and moisture on the performance of Wells turbines has not yet been studied in the field of ocean energy. Researchers have reported substantial differences between predicted and measured power output, and performance rates of OWCs presently coming into operation. The effect of moisture in the air chamber of the OWC causes variations on the atmospheric conditions near the turbine, modifying its performance and efficiency. Discrepancies in available power to the turbine are believed to be due to the humid air conditions, which had not been modelled previously. This thesis presents a study of the influence of humid air on the performance of an idealised Wells turbine in the chamber of an OWC using a real gas model. A new formulation is presented, including a modified adiabatic index, and subsequent modified thermodynamic state variables such as enthalpy, entropy and specific heat. The formulation is validated against experimental data, and found to exhibit better agreement than the ideal approach. The analysis indicates that the real gas behaviour can be explained by a non{dimensional number which depends on the local pressure and temperature in the OWC chamber. A first approach to the OWC formulation through the calculation of real air flow in the OWC is given, which predicts a 6% decrease in efficiency with respect to the ideal case when it is tested with a hypothetical pulse of pressure. This is important because accurate prediction of efficiency is essential for the optimal design and management of OWC converters. A numerical model has also been developed using computational fluid dynamics (CFD) to simulate the OWC characteristics in open sea. The performance of an OWC turbine is studied through the implementation of an actuator disk model in Fluent®. A set of different regular wave tests is developed in a 2D numerical wave flume. The model is tested using information obtained from experimental tests on a Wells{type turbine located in a wind tunnel. Linear response is achieved in terms of pressure drop and air flow in all cases, proving effectively the applicability of the actuator disk model to OWC devices. The numerical model is applied first to an OWC chamber containing dry air, and then to an OWC chamber containing humid air. Results from both cases are compared, and it is found that the results are sensitive to the degree of humidity of the air. Power decreases when humidity increases. Finally, results from the analytical real gas and numerical ideal gas models are compared. Very satisfactory agreement is obtained between the analytical and the numerical models when humidity is inserted in the gaseous phase. Both analytical and numerical models with humid air show considerable differences with the numerical model when dry air is considered. However, at the resonance frequency, results are independent of the gas model used. At every other frequency analysed, the real gas model predicts reduced values of power that can fall to 50% of the ideal power value when coupled to the radiation-diffraction model for regular waves. It is recommended that real gas should be considered in future analyses of Wells turbines in order to calculate accurately the efficiency and expected power of OWC devices.
226

Proyecto Phyra. Línea para el cuidado del hogar 100% natural / Phyra Project. Line for home care 100% natural

Kasano Soto, Gladys Thais, Luna Passano, Ariana Isabel, Romero Guerra, Diggi Becky, Tuesta Caro, Rodrigo Alfonso, Wong Torres, Milay Aileen 04 July 2019 (has links)
El trabajo de investigación se centra en el proyecto Phyra, el cual consiste en la venta online de productos 100% naturales para el cuidado del hogar, los cuales son: repelente, resinas aromatizadoras y antihumedad. Estos productos están dirigidos a Hombres y mujeres del NSE A, B, C1, entre las edades de 25 a 55 años y que residen en Lima Metropolitana; asimismo, que tengan un interés en el cuidado de su salud y sean ecorresponsables. Los experimentos realizados permitieron que se valide que el público objetivo tenía un problema con los productos actuales y estaban dispuestos a probar nuevas cosas, que finalmente le brinden una solución. Ante esto, se iniciaron las primeras ventas en la página de Facebook y se logró comprobar que Phyra era aceptado por el público. Con el resultado obtenido se buscó renovar el repelente en cuanto a su empaque y desarrollar dos nuevos productos. Todo esto fue también validado a través de las ventas. El contenido del trabajo se divide principalmente en la descripción del modelo de negocio, luego en la validación del mismo y finalmente, el desarrollo del plan de negocio, que incluye operaciones, RRHH, marketing, RSE y finanzas. Con todo esto se puede justificar la viabilidad del negocio. Finalmente se pudo concluir que el proyecto es rentable gracias al concierge realizado y al análisis de los estados financieros. Donde se obtuvo que la inversión inicial es de S/. 7,040.30 y se espera recuperarla en el primer año. / The research focuses on Phyra project, which consists of the online sale of 100% natural products for home care, which are: repellent, room odorizer resins and anti-humidity. These products are aimed at men and women of NSE A, B, C1, between the ages of 25 to 55 years and who reside in Metropolitan Lima; likewise, that they have an interest in health care and eco-responsible. The experiments carried out allowed the validation that the target audience had a problem with the current products and were willing to try new things, that finally provide a solution. Before this, the first sales on the Facebook page began and it was found that Phyra was accepted by the public. With the obtained result it was sought to renew the repellent in terms of its packaging and develop two new products. All this was also validated through sales. The content of the work is divided mainly in the description of the business model, then in the validation of the same and finally, the development of the business plan, which includes operations, HR, marketing, CSR and finance. With all this you can justify the viability of the business. Finally, it was concluded that the project is profitable thanks to the concierge carried out and the analysis of the financial statements. Where it was obtained that the initial investment is S /. 7,040.30 and it is expected to recover in the first year. / Trabajo de investigación
227

Physical and Electrical Characterization of Triethanolamine Based Sensors for NO₂ Detection and the Influence of Humidity on Sensing Response

Peterson, Zachariah Marcus 01 January 2011 (has links)
Triethanolamine (TEA) is a semiconducting polymer which exhibits a resistance change when exposed to various gases. The polymer also exhibits a number of reactions with nitrogen dioxide, with the reaction products being heavily dependent on the presence or absence of water vapor. Previous studies have attempted the incorporation of a TEA-carbon nanoparticle composite as the active sensing layer in a chemresistive sensor for detection of NO₂. The incorporation of carbon nanoparticles in the polymer nanocomposite was thought to amplify the sensor's response. There are a number of chemical reactions that can occur between TEA and NO₂, with the reaction products being heavily dependent on the presence and amount of water vapor in the environment. Because of this influence, it becomes necessary to know to what degree the presence of water vapor interferes with the sensing response. In this work we show that the sensor exhibits a reversible resistance change as background humidity changes. This sensitivity to humidity changes is so large that it renders undetectable any resistance change that could be caused by the reaction of TEA with NO₂. Furthermore, we show that the presence of low levels of NO₂ do not interfere with adsorption of water vapor. The detection mechanism is based on measuring resistance changes in the TEA film due to the adsorption/desorption of water vapor. The sensing response can be described by Langmuir adsorption by using a site-based model for the polymer film resistance. Breakdown of the polymer film over time due to continuous adsorption of water vapor, as well as photodegradation of the polymer film, will be discussed. SEM images will also be presented showing growth of crystallites on the electrode walls, as well as experimental results demonstrating degradation of the sensing film during sensor operation.
228

Investigation of Aerosol Optical and Chemical Properties Using Humidity Controlled Cavity Ring-Down Spectroscopy

Zhu, Xijing 04 December 2017 (has links)
Scientists have been observing a change in the climate since the beginning of the 20th century that cannot be attributed to any of the natural influences of the past. Natural and anthropogenic substances and processes perturb the Earth's energy budget, contributing to climate change. In particular, aerosols (particles suspended in air) have long been recognized to be important in processes throughout the atmosphere that affect climate. They directly influence the radiative balance of the Earth's atmosphere, affect cloud formation and properties, and are also key air pollutants that contribute to a variety of respiratory and cardiovascular diseases. Despite their importance, aerosol particles are less well-characterized than greenhouse gases with respect to their sources, temporal and spatial concentration distribution, and physical and chemical properties. This uncertainty is mainly caused by the variable and insufficiently understood sources, formation and transformation processes, and complex composition of atmospheric particles. Instruments that can precisely and accurately measure and characterize the aerosol physical and chemical properties are in great demand. Atmospheric relative humidity (RH) has a crucial impact on the particles' optical properties; the RH dependence of the particle extinction coefficient is an important parameter for radiative forcing and thus climate change modeling. In this work a Humidity-Controlled Cavity Ring-Down (HC-CRD) aerosol optical instrument is described and its ability to measure RH dependent extinction coefficients and related hygroscopicity parameters is characterized. The HC-CRD is capable of simultaneously measuring the aerosol extinction coefficient at three wavelengths (λ = 355, 532, and 1064 nm) and three different RHs (typically 20%, 50%, and 80%). A range of chemicals and their mixtures were used to produce laboratory generated aerosols. Three mixture systems include one inorganic salts mixture system consisting of (NH4)2SO4, NH4HSO4, Na2SO4, NaHSO4 serve as surrogates of the ionic salts found in the atmosphere. Two organic mixture systems were investigated: mixtures of NaCl, D-glucose, sucrose, and glycine are benchmarks for compounds emitted from biomass burning. Finally, mixtures of (NH4)2SO4 (ammonium sulfate, AS) with a series of dicarboxylic acids including malonic acid, adipic acid, and azelaic acid are used as benchmarks to mimic urban pollutants. The extinction coefficients were obtained as a function of RH from the HC-CRD measurements, from which optical growth factors f(RH) and γ(RH) values can be determined to examine their dependence on chemical composition. A volume mixing rule was used to calculate the effective refractive index of the binary substrate mixtures, since both size and composition change during water uptake. The SDA/FMC algorithm developed by O'Neill, et al. 2005 is used to extract the van de Hulst phase shift parameter (Ρeff) from three-wavelength measurements of extinction. The fine mode fraction of extinction (η) and fine mode effective radius (Reff) of laboratory generated aerosol particles can be then determined. An iterative algorithm was developed to retrieve the change in refractive index of particles as function of RH. The calculated Reff of aerosols at different RHs were used to obtain the physical size growth factor (gf), and κ(RH). The size changes as a function of water uptake describe the dependence of aerosol optical properties on chemical composition. This work demonstrates the capability of conducting aerosol optical measurements using HC-CRD to determine the RH dependence of aerosol optical properties. The HC-CRD measurements combined with the SDA/FMC method to retrieve aerosol size for laboratory generated aerosols establish the connection between the optical properties and the aerosol particles' chemical compositions. It also underlines the importance and need for future investigation on the hygroscopic properties of atmospheric aerosols. This work is successfully developed a method that enables using the aerosols optical measurements to predict the compositions; it will greatly contribute to the atmospheric aerosol measurement and global climate modelling.
229

Vliv teploty a vlhkosti vnějšího prostředí na rozmnožování včely medonosné (Apis mellifera) / Effect of temperature and humidity of the environment on reproduction of honeybees (Apis mellifera)

KAŠPARŮ, Miroslav January 2019 (has links)
The dissertation on the influence of temperature and humidity of the environment on the reproduction of the honey bee (Apis mellifera) describes the effect of the observed physical quantities on the entire bee during the growing season. Three habitats were monitored under different conditions. The measuring devices were always located inside and outside one colony of each habitat. In cooperation with colleagues from the Faculty of Electrical Engineering, ČVUT in Prague, the physical parameters monitoring was extended by monitoring the sound and weight of the hives - hive assemblies at the site located at the Agricultural Faculty of the University of South Bohemia. The data collection system in beehives was designed as a fully autonomous modular system. Measured data was processed and evaluated by statistical programs. The results showed that the hives observed differ in the number of bee queens found in the growing season and also in the number of frames found. Near-fetal temperatures were measured for correct development of the bee (32 °C to 36 °C). Colonies in the observed periods of 2014, 2015 and 2016 had to actively increase the relative humidity inside the hive in spring and summer. The colony reacts to changes in air temperature by varying intensity of sound. The results revealed the differences between the intensity of bee sounds in different temperature conditions. The highest sound intensity was detected at temperatures below 10 ° C (36.71 W.m-2), the lowest being at temperatures above 29.4 °C (26.25 W.m-2). The correlation coefficients were very low (r = 0.180) to medium (r = 0.463) and the correlation coefficient (r = 0.555) changed with a change in the temperature group. In order to evaluate the optimal conditions for honeybee rearing, the temperature and humidity monitoring can be used. The most suitable temperatures were in the range (29.5-34.3 °C) and temperatures above 34.4 °C. In terms of humidity, the temperature range (20-29.4 °C) and (29.5-34.3 °C) are the most appropriate. Changes in the observed values also affect the queen's bee in the colony. The data obtained from the long-term monitoring of these variables can help us to construct a THI index for bees, which would be a suitable tool to evaluate the optimal conditions for bees.
230

Ocean-Atmosphere Interactions on the West Florida Shelf

Virmani, Jyotika I 14 April 2005 (has links)
Ocean-atmosphere fluxes on the West Florida Shelf (WFS) coastal ocean region are investigated using observations and derived surface fluxes from an array of buoys deployed between 1998 and 2003. The observed annual cycle shows that water column temperatures increase and are stratified when heat flux is positive, and they decrease and are well mixed when it is negative. Water temperature is minimum (maximum) when heat flux switches sign from negative (positive) to positive (negative) in early spring (autumn). Tropical and extra-tropical events help define the seasonal characteristics of the water temperature. Despite considerable daily and synoptic variability in relative humidity, observations on the WFS show that the monthly mean values are nearly constant at about 75%. Winter relative humidity varies from less than 50% to over 100% (supersaturation values of up to 3% are recorded and coincide with fog on shore) as extra-tropical fronts move over the WFS. Sensor distribution shows small spatial variations in relative humidity in the coastal ocean environment that depends on high frequency variability in meteorological conditions and low-frequency variability in oceanic conditions. Comparisons with observations show that standard climatologies are unable to reproduce spatial variability on the WFS, especially in relative humidity and surface heat flux components that are dependent on sea surface temperature. Model experiments show that careful attention must be paid in calculating and applying surface heat fluxes. Observations and models are employed to assess the relative importance of surface fluxes and convergence of heat flux by the ocean circulation in controlling ocean temperature. In spring and autumn, seasonal change in water temperature is mainly controlled by surface heat flux with smaller contributions by ocean convergence, but synoptic scale variability is controlled by both surface heat flux and ocean circulation. Surface fluxes are of primary importance in determining water temperature during the passage of tropical storms or extra-tropical fronts. The coastal ocean temperature balance is fully three-dimensional. Models must be supported by adequate surface heat flux boundary conditions. These require sufficient numbers of in situ measurement points for constraining atmospheric models. The number of observations will depend on the spatial scales of SST variability.

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