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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.
11

Efeito dos extratos orgânicos de Annona muricata L. e Annona squamosa L. (Annonaceae) sobre o pulgão Aphis gossypii (Glover, 1887) (Hemiptera:Aphididae) e seletividade ao predador Eriopis connexa (Germar, 1824) (Coleoptera: Coccinellidae) / Effect of organic extracts of Annoma muricata L. and Annoma squamosa L. (Annonaceae) on the Aphid nymphs (Glover, 1887) (Hemiptera: Aphididae) and selectivity to the predator Eriopis connexa (German, 1824) (Coleoptera: Coccinellidae)

Santos , Lindinalva dos 20 July 2016 (has links)
The use of botanical extracts has been reported as an alternative to control insect pests in agricultural crops, but the harmful effects of these natural products on the beneficial insect fauna of agricultural ecosystems have to be assessed. The aim of this study was to evaluate the efficiency of seed extracts of sugar apple (Annona squamosa L.) and soursop (Annona muricata L.) on Aphis gossypii (Glover, 1887) (Hemiptera: Aphididae) and its natural enemy, the ladybug Eriopis connexa (Germar, 1824) (Coleoptera: Coccinellidae). Therefore, bioassays were performed with hexane and ethanol extracts at concentrations of 0.125; 0.25; 0.3; 0.4; 0.5; 1.0; 1.5 and 2.0%, to estimate by Probit analysis their lethal concentrations. For the ladybird, it was tested the action by contact, residual effect and ingestion to evaluate survival, oviposition and viability of the eggs. The CL50 and CL99 estimated for A. gossypii were, respectively, 0.39 and 5.47% for the ethanolic extract of sugar apple (EEP); 0.23 and 1.19% for the ethanolic extract of soursop (EEG); 0.47 and 4.39% for the hexanic extract of sugar apple (EHP); 0.42 and 6.38% for the hexanic extract of soursop (EHG). Considering the action of the extracts by contact, the EEG (0.23%) was considered innocuous, on the other hand, the EHG (0.42%) promoted mortality of 30% of insects and is classified as slightly harmful for 1st instar larvae; for adults, only EEP (5.47%) was classified as slightly harmful and the other treatments were classified as harmless, including for the residual effect. Regarding the selectivity of the extracts, the LC50 of EEG and EHG did not affect the survival rate of the ladybirds. By contrast, the EEP in both tested concentrations (0.39 and 5.47%) reduced the rate of survival to zero in less than 7 days, resembling the chemical treatment with Decis®. All treatments reduced the consumption of Anagasta kuehniella eggs, alternative prey, treated with the extracts, reducing the predation and causing as a consequence, oviposition to a decrease in lower concentrations and no egg laid for higher concentrations, affecting fertility and predator the viability of the eggs. The EEG in the concentration of 0.23% was effective in controlling A. gossypii, and its selective natural enemy E. connexa, not interfering with the survival rate of these. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O uso de extratos botânicos é uma alternativa de controle de insetos-praga em cultivos agrícolas, mas os efeitos desses produtos naturais sobre a entomofauna benéfica dos agroecossistemas são necessários. Com isso, o objetivo deste trabalho foi avaliar a eficiência dos extratos de sementes de pinha Annona squamosa L. e graviola Annona muricata L. sobre o pulgão Aphis gossypii (Glover, 1887) (Hemiptera: Aphididae) e seu inimigo natural, a joaninha Eriopis connexa (Germar, 1824) (Coleoptera: Coccinellidae). Para isso, foram realizados bioensaios com os extratos hexânico e etanólico nas concentrações: 0,125; 0,25; 0,3; 0,4; 0,5; 1,0; 1,5 e 2,0%, visando estimar por análise de Probit as concentrações letais. Para a joaninha, foi testada a ação por contato, efeito residual e ingestão para avaliação da sobrevivência, oviposição e viabilidade dos ovos. As CL50 e CL99 estimadas para A. gossypii foram respectivamente, 0,39 e 5,47% para extrato etanólico de pinha (EEP); 0,23 e 1,19% para extrato etanólico de graviola (EEG); 0,47 e 4,39% para extrato hexânico de pinha (EHP); 0,42 e 6,38% para extrato hexânico de graviola (EHG). Na ação dos extratos por contato, o EEG a 0,23% foi considerado inócuo, por outro lado, o EHG a 0,42% promoveu mortalidade de 30% dos insetos, sendo classificado como levemente nocivo para larvas de 1o instar; para adultos apenas o EEP (5,47%), foi classificado como levemente nocivo e os demais tratamentos foram classificados como inócuos, inclusive para o efeito residual. Quanto à seletividade dos extratos às joaninhas por ingestão, as CL50 do EEG e EHG não interferiram na taxa de sobrevivência dos predadores, por outro lado, o EEP nas duas concentrações testadas (0,39 e 5,47%) reduziram a zero a taxa de sobrevivência dos insetos em menos de 7 dias, se assemelhando ao tratamento químico Decis®. Todos os tratamentos reduziram o consumo de ovos de Anagasta kuehniella, presa alternativa, tratados com os extratos, diminuindo a capacidade predatória e, causando como consequência, a diminuição na oviposição para as concentrações menores e nenhum ovo posto para as maiores concentrações, afetando a fecundidade do predador e a viabilidade dos ovos. O EEG na concentração de 0,23% foi eficiente no controle de A. gossypii, e seletivo ao inimigo natural E. connexa, não interferindo na taxa de sobrevivência destes.
12

Design and Analysis of a Flapping Wing Mechanism for Optimization

George, Ryan Brandon 15 July 2011 (has links) (PDF)
Furthering our understanding of the physics of flapping flight has the potential to benefit the field of micro air vehicles. Advancements in micro air vehicles can benefit applications such as surveillance, reconnaissance, and search and rescue. In this research, flapping kinematics of a ladybug was explored using a direct linear transformation. A flapping mechanism design is presented that was capable of executing ladybug or other species-specific kinematics. The mechanism was based on a differential gear design, had two wings, and could flap in harsh environments. This mechanism served as a test bed for force analysis and optimization studies. The first study was based on a Box-Behnken screening design to explore wing kinematic parameter design space and manually search in the direction of flapping kinematics that optimized the objective of maximum combined lift and thrust. The second study used a Box-Behnken screening design to build a response surface. Using gradient-based techniques, this surface was optimized for maximum combined lift and thrust. Box-Behnken design coupled with response surface methodology was an efficient method for exploring the mechanism force response. Both methods for optimization were capable of successfully improving lift and thrust force outputs. The incorporation of the results of these studies will aid in the design of more efficient micro air vehicles and with the ultimate goal of leading to a better understanding of flapping wing aerodynamics and the development of aerodynamic models.
13

Modelling and Analysis of Daylight, Solar Heat Gains and Thermal Losses to Inform the Early Stage of the Architectural Process / Modellering och analys av dagsljus, solvärmelaster och värmeförluster i tidiga arkitektoniska projektskeden

Baker, Nicholas January 2017 (has links)
The EU building sector is a main contributor to greenhouse gas emissions, which need to be cut as part of the global response to anthropogenic climate change. This cut can be realised through improvements in building energy performance, such as optimisation of facade design. The early stage of the architectural process has been identified as the ideal time to implement such sustainable design choices. There is need for simple guidelines and tools to provide quantitative data to support these architectural decisions. BIM and parametric design can provide this, by facilitating model-based analysis and simulation, as part of an unbroken flow of information through the design process. This study uses Dynamo (the visual programming add-in for Autodesk Revit) together with the Honeybee and Ladybug environmental plugins, to conduct daylight, solar heat gains and thermal losses analyses and simulations. The aim was to identify limitations and opportunities in using Dynamo-Revit, to establish an optimal range for glazing-to-wall ratio (GWR) and to provide some simple room-sizing guidelines for architects in the early stage of the design process. The Dynamo-Revit workflow was found to be effective for specific projects, but difficult to perfect for multiple different projects. An optimal range for GWR was found as 30-40% for east, south and west-facing rooms and around 50% for rooms facing only north. Results were tabulated, linking room orientation and depth with estimated daylight access, solar heat gains and thermal losses. The results were reasonable, but could be improved by the use of more sophisticated analysis and simulation techniques, which should be facilitated by forthcoming development of Honeybee and Ladybug in Dynamo.
14

Jaroslavice – sídlo v krajině / Jaroslavice – place in the landscape

Šmejkal, Jiří January 2018 (has links)
The theme of this diploma thesis is the architectural study of the complex of the Farm of 3D Printers in Jaroslavice. The technology of 3D printing at its speed of development has far outweighed the response to its needs. It lacks a new systematically planned building typology corresponding to the requirements of farms. Farms adapt to the spaces. The main aim of the work is to introduce the possibility of turning the situation and adapting the premises to the farms. The thesis follows the urban design of the restructuring of the Jaroslavice landscape elaborated in the previous semester. The project respects established principles at microregion level in the form of emphasis on self-sufficiency, population integrity or the use of current technologies. The land is located on the southern part of Jaroslavice. There are 3 agricultural buildings located on the property, which until 2010, when a photovoltaic power plant was built, operated in conjunction with a neighboring agricultural court. After the power plant was built, the bonds were irreversibly broken. Buildings are in a very poor condition and mutual cooperation no longer works. The existing solution replaces and shows the possibility of using solar energy in a different way. Thus, the construction cartridge works with a hybrid typology where the 3D production area is combined with the maximum solar gains of the photovoltaic panels. Generative methods have been used to design dominantly either for finding a form in terms of achieving maximum solar gains or after verifying the efficiency of the structure. The proposal has several scenarios of possible development. There are four different stages of growth and the linkage of production areas. Printers are able to replicate themselves at such a rate that they can expect rapid growth. The proposal uses controlled growth methods to simulate complex development under the conditions of maximum solar radiation. Visual distraction and overheating are also solved by atypical sunsets on the exterior façade. Thin-film photovoltaic panels are used on the sun, so it is able to produce electricity besides the shield. The energy-efficient shape along with the great advantage of the layout solution, instead of the corridor disposition, is a basic cell on the central plan view. This makes it possible to control and operate more of the machines more efficiently. The production site forwards counts full robot automation.

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