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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.
161

Desenvolvimento e produção do algodoeiro em função de espaçamentos e aplicação de regulador de crescimento

Ferrari, Samuel [UNESP] 15 February 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-15Bitstream added on 2014-06-13T18:39:43Z : No. of bitstreams: 1 ferrari_s_me_ilha.pdf: 549681 bytes, checksum: ae8e08d93ae07c24cca8e73a2e455280 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O cultivo do algodoeiro passou de uma cultura de pequenos e médios produtores para uma realidade alicerçada em um modelo de produção em escala, caracterizado por altas produtividades e intenso uso de insumos e mecanização. Essa mudança ocasionou uma série de alternativas nas técnicas de cultivo, sendo crescente a indagação sobre alternativas às recomendações tradicionais sobre os vários tratos culturais e práticas agronômicas tais como época de semeadura, espaçamentos, densidade de plantas e emprego de reguladores de crescimento. O objetivo deste trabalho foi avaliar a influência de diferentes espaçamentos de cultivo e aplicação ou não de regulador de crescimento sobre o desenvolvimento, acúmulo de nutrientes e produtividade do algodoeiro em região de Cerrado. O delineamento experimental foi de blocos casualizados em esquema fatorial 3x3 com 9 tratamentos e 4 repetições, constituído por três espaçamentos: 0,45m, 0,70m e 0,90m entre linhas; Aplicação de cloreto de mepiquat na dose de 1,0 L ha-1 : a- aplicação parcelada em quatro etapas, b- aplicação única aos 70 dias após a emergência e c- sem a aplicação do regulador. Foi utilizada a cultivar de algodão Deltaopal. O experimento foi instalado no município de Selvíria (MS), na Fazenda de Ensino e Pesquisa da Unesp... / The cotton crop had changed the status of production from small to large scale, characterized by high yields and intensive use of fertilizers, agrochemicals and mechanization. That change caused a series of alternatives in the cultivation techniques, being growing the inquiry on alternatives to the traditional recommendations on the several cultural treatments and such agronomic practices as sowing time, spacings, density of plants and use of growth regulators. The objective of this study was to evaluate the influence of different row spacings in the cotton crop, with or without growth regulator and its effects in the development, nutrient uptake and yield in the Cerrado zone. The experimental design was the completely blocks in a factorial scheme 3x3 with 4 replications, with three row spacings: 0.45m, 0.70m and 0.90m; Application of mepiquat chloride using the dose of 1 L ha-1: a- split application in four stages, b- single application at 70 d.a.e and c-without application of the regulator. Was utilized the Deltaopal cotton cultivar. The trial was installed in the city of Selvíria (MS) out at the experimental farm of the Sao Paulo State University - Ilha Solteira Campus, in November of 2005 and the harvest realized in April of 2006... (Complete abstract click electronic access below)
162

Assistência de ar e volumes de aplicação associados a pontas de pulverização no controle de Spodoptera frugiperda (J. e. Smith, 1797) na cultura do milho

Gimenes, Marcelo Júnior [UNESP] 22 July 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-22Bitstream added on 2014-06-13T21:01:00Z : No. of bitstreams: 1 gimenes_mj_dr_botfca.pdf: 1534525 bytes, checksum: 3d0bd013733157c4e669fa55cb06798f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A alta demanda por produtos fitossanitários nos sistemas de produção, aliada ao possível uso inadequado, torna a tecnologia de aplicação uma das principais alternativas para otimizar a eficiência desses produtos em pulverizações agrícolas. Nesse contexto, o trabalho objetivou avaliar o desempenho da assistência de ar junto à barra, diferentes tipos de pontas, bem como volumes de calda sobre os depósitos da pulverização, controle da lagarta-docartucho e desempenho da cultura do milho conduzido em sistema adensado de semeadura. Dois experimentos foram conduzidos na área experimental da Fazenda de Ensino, Pesquisa e Produção (FEPP) da Faculdade de Ciências Agronômicas, UNESP, Câmpus de Botucatu/SP. Um experimento foi instalado durante o ano agrícola de 2008/2009, no delineamento de blocos casualizados em esquema fatorial (2x2+1), com quatro repetições. Foram avaliadas duas pontas de pulverização (ponta de jato plano e ponta de jato cônico vazio) combinadas com dois níveis de assistência de ar junto à barra de pulverização (com e sem assistência de ar), além de um tratamento testemunha. O outro experimento foi realizado no ano agrícola de 2009/2010, na mesma área experimental e sob o mesmo delineamento que o experimento anterior. Utilizou-se, neste caso, duas pontas de pulverização de jato plano (com e sem indução de ar) combinadas a dois volumes de pulverização (100 e 200 L ha-1), além de um tratamento testemunha. Nas pulverizações de ambos os experimentos, foi utilizado o inseticida Spinosad na dosagem de 48 g i. a. ha-1. A assistência de ar junto à barra de pulverização incrementou os depósitos da pulverização no estádio de desenvolvimento V4 da cultura do milho. Ainda, o uso dessa tecnologia proporcionou maiores eficiências de controle da lagartado- cartucho, chegando ao nível de 100% com 15 dias após a aplicação, no estádio... / The high pesticides demand in production systems, coupled with the possible inappropriate use, becomes the application technology one of the main alternatives to optimize the products efficiency in agricultural spraying. In this context, the study aimed to evaluate the performance of air assistance in spray boom, different kinds of nozzles, as well as spray volume on spray deposits, fall armyworm control and crop corn performance in narrow row sowing system. Two experiments were carried out at experimental area of Teaching, Research and Production Farm (TRPF) from Faculty of Agricultural Sciences, UNESP, Campus of Botucatu/SP, Brazil. One experiment was conducted during the 2008/2009 agricultural season, in randomized blocks with factorial scheme (2x2 +1), with four replications. They were tested two spray nozzles (flat fan nozzle and hollow cone nozzle) combined with two air assistance levels in the spray boom (with and without air assistance) and a control treatment. The other experiment was carried out in the 2009/2010 agricultural season, in the same experimental area, using the experimental design as the previous experiment. In this case, they were tested two flat fan nozzles (with and without air induction), combined with two spray volumes (100 and 200 L ha-1), plus a control treatment. In both experiments spraying, Spinosad insecticide was sprayed with amount of 48 g a. i. ha-1. The air assistance in the spray boom increased the spray deposits in V4 growth stage of corn plants. Moreover, the application of this technology showed higher efficiency on fall armyworm control, reaching the level of 100% at 15 days after spraying, in the V10 growth stage of corn plants. The hollow cone nozzle increased the spray deposits level on corn plants when compared with flat fan nozzles, in the growth stage V4. However, the flat fan nozzle, combined with air assistance technology was more effective... (Complete abstract click electronic access below)
163

Resposta do algodoeiro adensado ao nitrogênio em sucessão de culturas / Narrow row cotton response to nitrogen rate in crop rotation

Luiz César Bonfim Gottardo 14 September 2012 (has links)
A produção de algodão (Gossypium hirsutum L.) em sistema adensado iniciou no Brasil na safra 2008/09 com objetivo de aumentar a lucratividade da propriedade, por meio da intensificação de uso do solo e redução de custos. Este sistema é, substancialmente, alterado em relação ao convencional, pelo aumento da população de plantas, semeadura tardia (segunda safra) e em relação a dose do nitrogênio. O objetivo desta pesquisa consiste em conhecer o comportamento do algodoeiro adensado ao fornecimento de nitrogênio, em razão da cultura antecessora. O algodoeiro foi semeado em quatro tipos de sucessão: (i) sobre soja (Glycine max L.) sucedida de milheto (Pennisetum glaucum L.); (ii) sobre resíduo da soja; (iii) sobre resíduo do milheto; e (iv) em pousio, na ausência de cultura antecessora e controle de plantas daninhas. Em cada situação o algodoeiro foi conduzido sem nitrogênio e nas doses de 50 kg ha-1; 100 kg ha-1; e 200 kg ha-1 de N. A dose de nitrogênio para a máxima produtividade do algodoeiro adensado variou com a presença do resíduo, 88 kg ha-1 na sucessão milheto com soja, 127 kg ha-1 na sucessão a soja e na sucessão ao milheto ou ao pousio a produtividade foi inferior, com resposta linear até a dose 200 kg ha-1. O crescimento vegetativo foi maior com a aplicação do nitrogênio, mas a produtividade teve resposta quadrática ao fornecimento do nutriente. A produtividade foi maior quando cultivado sobre palha de milheto com soja (maior quantidade e relação C/N de 26), mesmo em menor doses de N do que nas outras palhas. A presença de palha, independentemente da relação C/N, contribui para o ganho em qualidade da fibra. / In Brazil, the narrow row cotton (Gossypium hirsutum L.) system started in the 2008/09 crop season aiming to increase farms profit, by intensive land use and lower productions costs. This system is substantially altered from the conventional (wide row), due high plant population, late sowing (second crop) and nitrogen management. With a target to know the nitrogen response of narrow row cotton in succession, the cotton was sowed in four situations: (i) after a succession of millet (Pennisetum glaucum L.) and soybeans (Glycine max L); (ii) after soybeans; (iii) after millet; and (iv) without previous culture and with weeds control. In each situation the cotton was farmed without nitrogen application and with rates of 50 kg ha-1; 100 kg ha-1; and 200 kg ha-1 of nitrogen. The nitrogen rate of maximum productivity was dependent on the preceding crop, 88 kg ha-1 after succession of millet and soybeans, 127 kg ha-1 after soybeans and in succession of millet or without previous culture the productivity was lower, with linear response until 200 kg ha-1. The vegetative growth was higher with nitrogen application, but the productivity had quadratic response to nitrogen fertilization. The higher productivity was on cotton sowed upon the millet with soybeans straw (more quantity of straw and relation C/N 26), even with less nitrogen than in the other straws. On the presence of straw, independent of C/N relation, the fiber quality was better.
164

Espaçamentos e densidades populacionais em cultivares de algodoeiro com direfentes arquiteturas de plantas / Row spacing and plant population density for differentiated plant architecture cotton cultivars

Raquel Capistrano Moreira 08 August 2008 (has links)
O presente trabalho teve por objetivo avaliar diferentes espaçamentos entre linhas e densidades de plantas em três cultivares de algodoeiro com diferentes arquiteturas de plantas. Os experimentos foram conduzidos no ano agrícola 2005/2006 no Centro Experimental Central, do Instituto Agronômico, em Campinas-SP, no Pólo Regional do Noroeste Paulista, da APTA, em Votuporanga-SP e na Fazenda de Ensino e Pesquisa da Unesp, Campus de Ilha Solteira, em Selvíria-MS. O delineamento experimental utilizado foi em blocos ao acaso, em esquema fatorial 2x2x3, com 4 repetições, sendo dois espaçamentos entre linhas (0,45 e 0,90 m), duas densidades de semeadura (6 e 10 plantas.m-1) e três cultivares (IAC 24, DeltaOpal e Fibermax 966). Em cada parcela experimental foram tomadas 4 plantas ao caso e avaliadas as seguintes variáveis: altura final das plantas, altura de inserção do 1° ramo frutífero, diâmetro do caule, número de ramos reprodutivos e número de capulhos por planta. Em Votuporanga foram determinadas a incidência de podridão de maçãs e a espessura do pericarpo de maçãs jovens. Amostras de 20 capulhos foram colhidas em cada parcela experimental, para a avaliação dos componentes da produção: massa de um capulho, massa de 100 sementes e porcentagem de fibra (apenas no experimento de Campinas); e para as análises das características tecnológicas da fibra: comprimento, uniformidade de comprimento, tenacidade, micronaire e maturidade. Em Campinas foi determinada a produção de algodão em caroço na área útil de cada parcela do experimento. De acordo com os dados obtidos, pôde-se concluir que: a utilização de espaçamentos mais largos acarreta maior altura final das plantas, maior diâmetro do caule, maior número de ramos reprodutivos e número de capulhos por planta; a utilização de espaçamentos entre 0,45 e 0,90 m e densidades de plantas entre 6 e 10 plantas.m-1 não acarreta em diferenças na produtividade do algodoeiro; em condições de menor competição entre plantas e maior penetração de luz no dossel, isto é, sob espaçamentos mais largos e/ou menor densidade de plantas na linha, o algodoeiro prioriza a produção de fibras; independente da cultivar e do espaçamento adotado, o índice micronaire pode aumentar com a redução do número de plantas na linha; a incidência de podridão de maçãs do algodoeiro, bem como sua severidade, estão relacionadas ao genótipo utilizado, quer seja pela arquitetura da planta como também pela espessura do pericarpo dos frutos. / The aim of this work was to evaluate different row spacings and plant population densities for three cotton cultivars with different plant architecture. The experiments were carried out in experimental areas belonging to Instituto Agronômico, in Campinas- SP, at Pólo Regional do Noroeste Paulista, from APTA, in Votuporanga-SP and at Unesp Campus de Ilha Solteira, in Selvíria-MS. A randomized block design was used, with four replicates, in a factorial 2x2x3 scheme, with two row spacings (0.45 and 0.90 m), two plant population densities (6 and 10 plants.m-1) and three cotton cultivars (IAC 24, DeltaOpal e Fibermax 966). Four plants per plot were labeled and analyzed for the plant height, insertion height of the first fruit branch, stem diameter, number of fruit branches and open bolls per plant. In Votuporanga were also analyzed the boll rot incidence and the pericarp thickness of young bolls. Samples of 20 open bolls randomized chosen per plot were analyzed for yield components: average open boll mass, 100 seeds mass, and fiber percentage, just on the Campinas experiment; and for fiber technological characteristics: length, length uniformity, strength, micronaire and maturity. In Campinas the cotton yield was determinated in the useful area of each plot. According to the experimental data obtained it was possible to conclude: the use of wider row spacing leads to a greater plant height, larger stem diameter, greater number of fruit branches and bolls per plant. The use of row spacing varying from 0.45 to 0.90 and plant densities varying from 6 to10 plants.m-1 do not affect cotton yield; under lower plant competition and higher light levels in the canopy, that is, in wider row spacing and/or lower plant population, the fiber production is prioritized by the cotton plant; independently of the cultivar and row spacing, the micronaire may increase with plant population reduction; the boll rot incidence, as well as its severity, are related to plant genotype, due to either plant architecture and pericarp thickness.
165

Skid road, Vancouver : an exploratory study of the nature and organization of skid road and the effectiveness of existing social policy

Hein, Hubert January 1966 (has links)
Similar to most other large North American cities, that area of Vancouver which at the beginning of the present century was at the hub of a young and vigorous regional economy, is now playing host to the castoffs of our society made up of those who are suffering from physical and emotional ill health or have fallen by the wayside because of poverty and lack of skills and education. The social agencies serving the area recognize that by and large their efforts are only of an emergency nature and leave the basic problems untouched. A comprehensive program to deal effectively with the problems of skid road requires resources beyond the means of these agencies and will require extensive support, financial and otherwise, from civic and senior governments. A number of the agencies serving the area have been instrumental in bringing the dilemma to the attention of civic authorities and in recommending remedial and preventive action. Studies and programs which have been undertaken on Skid Road in the United States, point the way to a solution of similar problems in Vancouver. At the same time research on the subject is still relatively limited, and much more needs to be known, especially of the situation as it exists at the local level. The present study is intended to add to the fund of basic knowledge on Skid Road in Vancouver. This is a necessity if effective planning and action are to take place. In the introductory chapter Skid Road is portrayed in terms of its historical and present physical and social characteristics. A review of two recent studies on Skid Road in Vancouver familiarized the reader with some of the problems of the area and suggests possible ways of coping with these. A few observations on newspaper coverage of the area conclude the chapter. In Chapter II a summary of several studies and projects on Skid Road in the United States offers a means of comparison to the local scene. The second half of the thesis focuses on an examination of the problems and social policy of Skid Road in Vancouver, as seen by representatives of social agencies serving the area and the clientele served. The purpose of the study, its scope, and the materials and methods used, are outlined in greater detail. In chapter 4 the research data are classified and presented in table form where appropriate. A brief analysis of the data is also presented. The final chapter contains observations on the research project and its findings as a whole. The thesis ends with a number of recommendations and conclusions on the basis of the findings. The study was intended primarily as a further exploration of the problem area. Definite conclusions were not expected. At the same time, the following observations deserve closer consideration. It was felt that particular attention be given to the establishment of: a) a multipurpose agency in the Skid Road area b) a variety of hostels and halfway houses located throughout the city c) a coordinating body to deal with Skid Road problems / Arts, Faculty of / Social Work, School of / Graduate
166

Death sentence experience: The impact on family members of condemned inmates

Vallejo, Catherine Anne 01 January 1995 (has links)
No description available.
167

Produktivitetsskillnader efter införandet av drivningsmetoden Skonsam Effektiv Drivning hos SCA skog AB Medelpads skogsförvaltning / Differences in productivity after implementing the forest operation method Gentle Efficient Logging Technique in SCA forest administration in Medelpad Sweden

Nordström, Martin January 2020 (has links)
The enviromental footprint on the planet is something that societies andorganizations all over the world are trying to reduce. The forestry sector is not anexception in that matter and work is going on in several areas, among them reductionof soil damages. At the same, competition is constantly pressing the economicalmarginal, increasing the importance of cost-efficiency.This study’s aim was to compare two different methods of forest operations, theSCA-method SED (reducing the risk of damages) with traditional.The study was carried out as a quantative method study by comparing theproductivity of the two methods with three logging teams from autumns 2017 and2018.This study showed that SED only marginally increased the harvesting team’sproductivity compared to traditional cutting.Logging technique, Gentle efficient logging technique, SED, Strengthening actions,ghost row.
168

Analyzing the Effects of Autonomous Navigation on Row Crop Farming

Eric Kong (11150976) 03 August 2021 (has links)
As the global population rises, so does the demand for food, feed, fiber, and fuel. Meeting this demand has become increasingly difficult due to the decline in farm labor and challenges associated with the economic viability of agricultural systems. Autonomous agricultural machinery has the potential to mitigate some of major challenges that crop production systems will face. Widespread adoption of autonomous machinery is dependent on two key factors, the cost and environmental impact. The development and adoption of autonomous vehicles will only occur if it is profitable for equipment manufacturers and farmers. As distillate fuel use for crop production increases, fuel efficient operations that minimize greenhouse gas emissions will mitigate the environmental impact of farming.<br><div><br></div><div>The objective of this research was to develop a model to quantify the cost, energy use, and emissions associated with the use of agricultural machinery used for row crop farming. The model calculates the cost of different sized machinery fleets for planting and harvest. Autonomy facilitates swarm farming, and the model can quantify and compare these to human-operated machinery systems.<br></div><div><br></div><div>For an 800-hectare case study farm in the Midwest, with the acreage split evenly between corn and soybeans, the most cost-effective planting machinery fleet was comprised of two autonomous, 56-kW JD 5075E tractors pulling 4-row planters ($40/ha/yr). The most cost-effective fleet used the most fuel (4,327 liters) and produced the most emissions (219,735 grams). For a similar conventional system to complete planting during the same working window, it would require 4 tractors and cost $75/ha/yr. The $35/ha/yr difference between the similar fleets was the value added by autonomy. Current row crop farming trends have shifted towards fewer operators with larger machines and implements. The most cost-effective, single operator machinery set from the database (Case Magnum 200 with a 16-row planter) costs $43/ha/yr more than overall most cost-effective fleet. Total fuel used to complete the planting operation was minimized by using a single John Deere 8320R pulling a 36-row planter. To plant all 800-hectares, the 8320R used 2,528 liters of diesel fuel and produced a combined 44,002 grams of emissions. The JD 5075E was able to minimize cost, but it used the most fuel and produced the most greenhouse gas.<br></div><div><b><br></b></div>
169

Zlepšení hydraulických vlastností vírových turbin / Improving of hydraulic properties of swirl turbines

Kůrečka, Jan January 2016 (has links)
This diploma thesis describes design of blade geometry of swirl turbines with different blade row density for given parameters Q11 = 1,9 [m3s-1], n11 = 170 [min-1], H=2,5 m, and =0,8. Goal is to found out differences between designs with high count of runner blades and design with fewer blades. Comparison of computed characteristics of three, seven and nine bladed runners is given.
170

Silage Corn Hybrid Response to Row Width and Plant Density in the Intermountain West

Pieper, Mark A. 01 August 2018 (has links)
Corn (Zea mays L.) hectarage has increased rapidly in Utah and Idaho in recent years due to expansion of the dairy industry, but little is known about corn production practices that optimize yield and quality of silage corn in semi-arid irrigated cropping systems. The objective of this study was to determine the dry matter yield and quality effects of corn hybrids grown in different plant densities and row widths in the Intermountain West. Field experiments were conducted under irrigation in 2015 and 2016 at locations near North Logan, Utah and Jerome, Idaho. The experimental design was a randomized complete block in a split-split plot arrangement with four replications. The whole plot treatment was hybrid (DKC 49-29, DKC 56-54, and DKC 61-88), the sub-plot treatment was row width (76 and 51-cm), and the sub-sub plot treatment was plant density (61,776 to 123,552 plants ha-1 at intervals of 12,355 plants ha-1). The 51-cm row width resulted in forage dry matter yield increases of 4-7% over corn in 76-cm rows. Hybrids differed in response to row width, with no difference detected for the 99-RM hybrid but a significant yield increase for the 106- and 111-RM hybrids by planting in narrow rows. Yield increased quadratically as plant population increased from 61,776 to 123,552 plants ha-1 for all hybrids. The only forage nutritive value that was influenced by row spacing was crude protein (CP), where the 76-cm row spacing showed a 4.5% advantage over the 51-cm row width. Starch increased approximately 3% from the lowest to highest plant densities tested. Net returns showed possible positive increases when comparing row width adjustments. Silage corn yield and quality in the Intermountain West appears to be optimized in 51-cm rows at a plant population between 86,487 and 98,842 plants ha-1.

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