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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.
181

Transplante manual e semimecanizado da cultura do brócolis em preparo de solo convencional e direto / Manual and semimecanized transplants of the broccol culture in the preparation of conventional and no tillage

Consoline, Laís Busca 10 May 2018 (has links)
Submitted by Laís Busca Consoline (lais_consoline@hotmail.com) on 2018-07-04T20:27:41Z No. of bitstreams: 1 Dissertação LAIS BUSCA CONSOLINE.pdf: 2004176 bytes, checksum: b5fba012a386c177b0dc245c206b9c5b (MD5) / Approved for entry into archive by Maria Lucia Martins Frederico null (mlucia@fca.unesp.br) on 2018-07-05T11:25:33Z (GMT) No. of bitstreams: 1 consoline_lb_me_botfca.pdf: 2004176 bytes, checksum: b5fba012a386c177b0dc245c206b9c5b (MD5) / Made available in DSpace on 2018-07-05T11:25:33Z (GMT). No. of bitstreams: 1 consoline_lb_me_botfca.pdf: 2004176 bytes, checksum: b5fba012a386c177b0dc245c206b9c5b (MD5) Previous issue date: 2018-05-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / RESUMO Este trabalho teve como objetivo avaliar o desempenho operacional e a viabilidade econômica da operação de transplante de mudas de brócolis semimecanizado e manual em duas velocidades de deslocamento V1 e V2 (0,8 e 1,1 km h-1), comparando dois tipos de preparo de solo, preparo convencional e plantio direto. Foi utilizado para a realização do transplante o conjunto mecanizado composto pelo trator New Holland, modelo TL65® e a transplantadora Fedele Mario®. O delineamento experimental constituiu-se em blocos casualizados com fatorial duplo 3x2, no esquema de parcelas subdivididas, constituindo 2 parcelas de preparo de solo, convencional e direto, com três subparcelas, caracterizando os transplantes realizados de forma manual, semimecanizado em V1 e semimecanizado em V2. Foram abordados os seguintes tratamentos: transplante manual em plantio direto, transplante manual em plantio convencional, transplante semimecanizado com velocidade 1 em plantio direto, transplante semimecanizado com velocidade 1 em plantio convencional, transplante semimecanizado com velocidade 2 em plantio direto e transplante semimecanizado com velocidade 2 em plantio convencional. A área de plantio foi previamente semeada com milho (Zea mays) e manejada com triturador de palha para constituir os tratamentos em plantio direto. Para os tratamentos em plantio convencional foi realizada operações com a passagem do rotoencanteirador. As avaliações realizadas foram: desempenho operacional e econômico do transplante nos diferentes sistemas de preparo de solo e ainda a determinação da quantidade mínima de mudas a qual a máquina passa a ser vantajosa, diâmetro e peso de cabeça do brócolis e a produtividade. Os resultados demonstraram que o tipo de plantio, convencional ou direto não interferiu na produtividade do brócolis, assim como o transplante manual ou semimecanizado. Em média o transplante manual apresentou rendimento de 11 bandejas a menos por hora que o transplante semimecanizado na menor velocidade e 24 bandejas a menos na maior velocidade. Houve maior necessidade de repasse de mudas nos tratamentos com plantio direto em relação ao preparo convencional. O tratamento no sistema de plantio direto na maior velocidade de deslocamento apresentou menor custo operacional com R$586,00 por hectare. O número mínimo de mudas para o que o a troca de tecnologia (passar de plantio manual para mecanizado) seja economicamente vantajosa é de 217.080 mudas ao mês. / The operational development and the economic viability of the transplant of broccoli seedling, both semi-mechanized and manual in two dislocation speeds (1stand 2nd gear of the tractor) were evaluated, comparing different kinds of soil preparation, namely conventional and no tillage. The mechanized group composed by both a TL65® New Holland 4x2 tractor with 65 nominal power, and an Italian Fedele Mario MAX® transplanter were used for the transplantation. The experimental design was at random with the 3x2+2 factorial, corresponding to the two dislocation speeds of the transplanter in both soils and also the manual transplant in both soil prepare. The following treatments were examined: manual transplant in no tillage, manual transplant in conventional prepare, semi-mechanized transplant with speed 1 in no tillage, semi-mechanized transplant with speed 1 in conventional prepare, semi-mechanized transplant with speed 2 in no tillage, semi-mechanized transplant with speed 2 in conventional prepare. The planted area was previously sown with corn (Zea mays) and prepared with straw shredder to comprise the treatments in no tillage. Operations with rotoencanteirador were performed for the treatments in conventional prepare. The evaluations were on amount and percentage of straw in the soil, operational and economic development of the transplant in different systems of soil prepares and the determination of the number of seedling from which the machine begins to be advantageous. The agronomic evaluations were on the broccoli head diameter and its productivity. The results showed that conventional or direct tillage did not interfere with broccoli productivity, as did manual or semi-mechanized transplants. On average, the manual transplant presented yield of 11 trays less per hour than the semi-mechanized transplant at the lowest speed and 24 trays at less speed. There was greater need of transfer of seedlings in no-tillage compared to conventional ones. No-tillage at the highest displacement speed had a lower operating cost of R $ 586.00 per hectare. The minimum number of seedlings for which the exchange of technology is economically advantageous is 217,080 seedlings per month.
182

We just estimated twenty million fiscal multipliers

Capek, Jan, Crespo Cuaresma, Jesus 08 1900 (has links) (PDF)
We analyse the role played by data and specification choices as determinants of the size of the fiscal multipliers obtained using structural vector autoregressive models. The results, based on over twenty million fiscal multiplier estimated for European countries, indicate that many seemingly harmless modelling choices have a significant effect on the size and precision of fiscal multiplier estimates. In addition to the structural shock identification strategy, these modelling choices include the definition of spending and taxes, the national accounts system employed, the use of particular interest rates or inflation measures, or whether data are smoothed prior to estimation. / Series: Department of Economics Working Paper Series
183

Money demand in Eurozone and other European countries

Slezarová, Iva January 2014 (has links)
The goal of this thesis is to examine relationship between money demand, interest rates and real GDP in the Czech Republic, United Kingdom and Eurozone in time period 2005-2013. Apart from OLS regression the work will also focus on stability of the demand form money and exogeneity of money. In the thesis is among general tools as OLS and its variants used cointegration analysis for determination of exogeneity and other methods connected with it. For analysis were used quarterly data obtained from central banks of given countries and OECD statistical database.
184

Řízení rizik v komerční pojišťovně

Stránská, Martina January 2014 (has links)
The Diploma thesis deals with the risk management in an insurance company. The main goal of the thesis is to determine the process of the risk management in insurance companies and to compare this process with the theory and with requirements of directive Solvency II. The first part of the thesis specifies the issue from a theoretical view. The second part focuses on a real situation in insurance companies and concrete approaches of quantitative assessment of risks, such a Value at Risk and stress testing. The result of the thesis is the evaluation of readiness of insurance companies for implementation of directive Solvency II and recommendations for an improvement of the process of risk management.
185

Identification of Shocks and Imbalances in the European Union

Le, Thanh Tam January 2015 (has links)
The main objective of the thesis is to examine the asymmetric shocks and imbal-ances among the countries in the European Union. The shocks are identified with their nature and estimated in magnitudes by using the Vector Autoregressive models. From these models, the filtered residuals representing economic shocks were displayed on correlation matrices in order to assess the similarity level of their impacts on respective member states' economies. The empirical studies led to the conclusion that there exist some certain asymmetries in the EU and enabled some policy implications.
186

Moderné metódy ochrany slivkovín proti obaľovačovi slivkovému

Kysela, Pavol January 2016 (has links)
Thesis deals with advanced protection options against plum fruit mothCydia funebrana in organic and integrated production. A separate chapter is devoted to the characteristics, bionomy, the hosts plants and the importance of plum fruit moth. There are possibilities of monitoring and detection of the pest described in third chapter. The experimental part is devoted to comparison of productswith the active substance Bacillus thuringiensis var. kurstaki. There are two preparations compared Lepinox Plus and Biobit XL. The experiment was conducted in 2014 in a production orchard set in Brno Starý Lískovec. Product Lepinox Plusreached the highest efficiency.
187

Otimização de portfólios de comercialização de energia no Brasil

Ribeiro, Mário Guerreiro 22 May 2017 (has links)
Submitted by Mário Guerreiro Ribeiro (mariogr@poli.ufrj.br) on 2017-07-24T19:59:43Z No. of bitstreams: 1 Tese_MGuerreiro_Versao final.pdf: 1679486 bytes, checksum: 41cba20a3ce6b5eaeeb08b44f89fd439 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2017-07-27T13:48:10Z (GMT) No. of bitstreams: 1 Tese_MGuerreiro_Versao final.pdf: 1679486 bytes, checksum: 41cba20a3ce6b5eaeeb08b44f89fd439 (MD5) / Made available in DSpace on 2017-07-27T13:48:38Z (GMT). No. of bitstreams: 1 Tese_MGuerreiro_Versao final.pdf: 1679486 bytes, checksum: 41cba20a3ce6b5eaeeb08b44f89fd439 (MD5) Previous issue date: 2017-05-22 / The portfolio optimization analysis for quite some time was built around the variance measure. This approach is adequate when the assets returns are normaly distributed. However, in asymmetric or heavy-tailed distributions, the same weight cannot be given to the two tails of the distribution, what requires the use of other risk measures. One of the most known and widespread is VaR, but it cannot capture extreme events, is not a coherent measure and has optimization problems. For these reasons, the dissertation addresses the CVaR on the portfolio optimization for the Brazilian electric power sector. / A análise da otimização de carteiras por muito tempo foi pautada na medida da variância. Essa abordagem é propícia quando os retornos dos ativos são normais. Porém, em distribuições assimétricas ou com caudas pesadas não se pode dar o mesmo peso para as duas extremidades da distribuição, levando a necessidade da utilização de outras medidas de risco. Uma das mais conhecidas e difundidas é o VaR, porém o mesmo não consegue capturar eventos extremos, além de não ser uma medida coerente e possuir problemas de otimização. Por esses motivos, o CVaR é abordado para o caso da otimização de portfólios do setor de energia elétrica brasileiro.
188

Resposta do tomate cereja sob cultivo orgânico aos níveis de água e diferentes tipos de cobertura morta / Cherry tomato response under organic cultivation at the levels of water and different types of dead coverage

Silva, Valsérgio Barros da January 2017 (has links)
SILVA, Valsérgio Barros da. Resposta do tomate cereja sob cultivo orgânico aos níveis de água e diferentes tipos de cobertura morta. 2017. 63. f. Dissertação (Dissertação em Engenharia Agrícola)-Universidade Federal do Ceará, Fortaleza, 2017. / Submitted by Luís Camboim Neto (camboim@ufc.br) on 2017-11-24T22:21:02Z No. of bitstreams: 1 2017_dis_vbsilva.pdf: 764526 bytes, checksum: 304f1d39ec4b3d17659c9b78a7b944c9 (MD5) / Approved for entry into archive by Anderson Silva Pereira (anderson.pereiraaa@gmail.com) on 2017-11-30T21:17:11Z (GMT) No. of bitstreams: 1 2017_dis_vbsilva.pdf: 764526 bytes, checksum: 304f1d39ec4b3d17659c9b78a7b944c9 (MD5) / Made available in DSpace on 2017-11-30T21:17:11Z (GMT). No. of bitstreams: 1 2017_dis_vbsilva.pdf: 764526 bytes, checksum: 304f1d39ec4b3d17659c9b78a7b944c9 (MD5) Previous issue date: 2017 / Studies on the production of irrigated organic cherry tomatoes in the semi-arid region are still incipient, regarding the aspect of adequate irrigation management, especially in the case of the water crisis in the State of Ceará, with rains in the last few years below average and reserves ending up of water. In this sense, the present work had as objective the technical and economic evaluation of the effect of the different irrigation slides and soil cover on the cherry tomato production, from August 2016 to January 2017. The experiment was carried out in an área belonging to the Education Program in cooperative cells - (PRECE), in the municipality of Pentecoste. Conducted in randomized blocks, with three replications and subdivided plots, comprised of five primary treatments in the plots and three secondary treatments arranged in the subplots.The primary treatments consisted of five irrigation levels with 50, 75, 100, 125 and 150% of evapotranspiration of the culture for localized irrigation (ETcloc) and three secondary treatments consisting of two soil coverages, bagana de carnauba (BC) and elephant grass EC; In addition to a control treatment, soil without cover.The water used for irrigation came from a shallow well located on the banks of the Canindé River.The crop was irrigated by a drip irrigation system.The results obtained allowed us to conclude that an area of around 0.5 ha is necessary to guarantee sufficient income for the maintenance of each worker in the family. / Estudos sobre a produção de tomate cereja orgânico irrigado no semiárido, ainda são incipientes, no que se refere ao aspecto do manejo adequado da irrigação, principalmente, diante do cenário de crise hídrica no Estado do Ceará com chuvas nos últimos anos abaixo da média e reservas hídricas se exaurindo. Neste sentido, o presente trabalho teve como objetivo a avaliação técnica e econômica do efeito das diferentes lâminas de irrigação e coberturas do solo sobre a produção do tomate cereja, no período de agosto de 2016 a janeiro de 2017. O experimento foi realizado em uma área pertencente ao Programa de Educação em Células Cooperativas - (PRECE), no município de Pentecoste. Conduzido em blocos ao acaso, com três repetições e parcelas subdivididas, compreendidas em cinco tratamentos primários nas parcelas e três tratamentos secundários dispostos nas subparcelas. Os tratamentos primários foram constituídos por cinco níveis de irrigação com 50, 75, 100, 125 e 150% da evapotranspiração da cultura para irrigação localizada (ETcloc) e três tratamentos secundários constituídos por duas coberturas do solo, bagana de carnaúba –BC e capim elefante – CE; além de um tratamento testemunha, solo sem cobertura. A água utilizada na irrigação foi proveniente de poço raso localizado às margens do Rio Canindé. A cultura foi irrigada através de um sistema de irrigação por gotejamento. Os resultados obtidos permitiram concluir que uma área em torno de 0,5 ha é necessária para garantir renda suficiente à manutenção de cada trabalhador da família. A bagana de carnaúba demonstrou grande potencial como cobertura morta para minimizar a queda no rendimento da cultura de tomate cereja em condições de estratégia de irrigação com déficit.
189

Portafolio de inversión con commodities : aplicación de value at risk (VaR) y otras metodologias

Silva Canales, Nicolás Ignacio 04 1900 (has links)
TESIS PARA OPTAR AL GRADO DE MAGÍSTER EN FINANZAS / Este trabajo tiene como principales objetivos el demostrar que aquellos portafolios con commodities entregan un mayor beneficio para el inversionista, y al mismo tiempo mostrar, mediante su utilización, diferentes metodologías, que siendo algunas bastante sencillas, pueden ser de mucha utilidad. Estas metodologías se utilizan para medir la capacidad que tienen los commodities para diversificar el riesgo y de esta forma obtener mejores rentabilidades sin aumentar la volatilidad, o sea, sin aumentar el riesgo al hacer las inversiones. Los resultados determinan que los commodites muestran una buena capacidad de disminuir la volatilidad de los portafolios y permiten alcanzar un mejor desempeño. / The main objective of this paper is to demonstrate that these portfolios with the commodities provide a greater benefit to the investor, and at the same time to show, through their use, different methodologies, which are very simple, but also can be very useful. These methodologies are used to measure the ability of commodities to diversify risk and this way to obtain better returns without increasing the volatility, that is, without increasing the risk when making the investments. The results determine that the commodities have a good ability to reduce the volatility of the portfolios and achieve a better performance.
190

Distribuição de funções de variáveis aleatórias dependentes e R-Vines cópulas

Maluf, Yuri Sampaio 08 December 2015 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Estatística, 2015. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-03-22T19:46:38Z No. of bitstreams: 1 2015_YuriSampaioMaluf.pdf: 4291479 bytes, checksum: 4a9954a7905294836d257652f0ce1753 (MD5) / Approved for entry into archive by Marília Freitas(marilia@bce.unb.br) on 2016-05-26T16:30:44Z (GMT) No. of bitstreams: 1 2015_YuriSampaioMaluf.pdf: 4291479 bytes, checksum: 4a9954a7905294836d257652f0ce1753 (MD5) / Made available in DSpace on 2016-05-26T16:30:44Z (GMT). No. of bitstreams: 1 2015_YuriSampaioMaluf.pdf: 4291479 bytes, checksum: 4a9954a7905294836d257652f0ce1753 (MD5) / Neste trabalho, estudamos a formulação da distribuição de funções de variáveis aleatórias contínuas dependentes. O mecanismo de modelagem da dependência é feita via funções cópulas. Dentre os resultados obtidos formulamos a expressão geral da distribuição da soma de n variáveis aleatórias dependentes. Expandimos a abordagem para a distribuição de outras funções de variáveis aleatórias tais como o quociente, produto e uma combinação convexa. Por meio das R-Vines Cópulas, obtivermos também a expressão da soma de n variáveis aleatórias em que cada componente é governada por um processo GARCH. A partir deste resultado, calculamos o Value-at-Risk (VaR) e Expected Shortfalls (ES) da soma dessas variáveis. Em função desta estrutura, as medidas de risco passam a adquirir um comportamento dinâmico. Ao final do trabalho exibimos algumas ilustrações numéricas via simulação de Monte Carlo. Apresentamos também uma aplicação com dados reais provenientes de bolsas de valores da América Latina. / In this thesis, we studied the distribution of function of dependents continuous random variables. The modeling dependencies structures are made via copula functions. We obtain the general expression of the distribution of the sum of n dependents random variables. This approach is expanded for other functions such as ratio, product and a convex combination. Using R-Vines Copulas, we also derive an expression of the sum of n dependents random variables, being each component governed by AR-GARCH process. From these results, we assess the Value-at-Risk (VaR) and Expected Shortfalls (ES) of the sum of these variables. According to this structure, the VaR takes a dynamic behavior. At the end of this thesis, we show some numerical illustrations via Monte Carlo simulation. An application with real data from Latin American stock markets is also presented.

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