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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.
141

Line Width Parameters and Center Frequency Shifts in the Rotational Spectrum of Methyl Cyanide

Swindle, David L. 05 1900 (has links)
Measurement of the line width parameters of a molecule is of interest because collision diameters can be calculated from them. This gives an effective size of the molecule when it is involved in interactions with other molecules. Further, specific types of interactions can be inferred from detailed information about the dependence of the line width upon pressure. In this paper, an experiment for measuring line width parameters for methyl cyanide is described and the results of the experiment are analyzed. This investigation was successful in obtaining precise values for the line width parameter for the J-J' = 0-1, J-J'= 1-2, and J-J' = 2-3 transitions of methyl cyanide which agree with experimental values of other researchers where available. It was found that standing waves were the dominant effect in the measurement of center frequency shift.
142

Estudo da largura efetiva de vigas mistas de aço-concreto em carregamento de serviço : método dos elementos finitos versus códigos de projeto / Estudo da Largura Efetiva de Vigas Mistas de Aço-Concreto em Carregamento de Serviço: Método dos Elementos Finitos versus Códigos de Projeto

Reginato, Lucas Henrique January 2017 (has links)
Com a crescente utilização de vigas mistas de aço e concreto em obras civis e devido à insuficiência de estudos relativos ao seu comportamento estrutural, investigações aprofundadas são necessárias para suprir as carências e aperfeiçoar o tema. Um fenômeno familiar na literatura de estruturas mistas é a distribuição não uniforme de tensões ao longo da largura da laje de concreto, denominado shear lag na literatura inglesa. Na análise e projeto de estruturas compostas, deflexões, tensões e resistência são tipicamente obtidas utilizando-se o conceito de largura efetiva, na qual o efeito shear lag é contabilizado indiretamente, substituindo a largura real da laje, por uma largura apropriadamente reduzida. Sem dispor de análises numéricas exatas para o dimensionamento prático, é necessário que códigos normativos forneçam métodos simplificados para a avaliação da largura efetiva minimizando perdas de precisão. Diante disso, no presente trabalho, procedimentos numéricos para a avaliação da largura efetiva, encontrados na literatura técnica, foram estudados e implementados ao modelo matemático em elementos finitos disponível no CEMACOM/PPGEC/UFRGS, capaz de representar com confiabilidade estruturas mistas. Comprovando-se a eficácia do modelo numérico em captar o efeito do shear lag, a resposta de uma viga mista biengastada, representando um vão intermediário de uma ponte contínua, submetida a um carregamento em longo prazo, e considerando-se os fenômenos reológicos do concreto de fluência e retração, além do comportamento não-linear devido a fissuração, é obtida e comparada à fórmulas estipuladas nas principais normas de projeto e em metodologias desenvolvidas por pesquisadores. Falhas potenciais nos códigos de projeto atuais foram evidenciadas, necessitando-se de adicionais estudos paramétricos experimentais e numéricos para a comprovação dos resultados. / With the increasing use of steel-concrete composite beams in bridges and buildings more investigations related to this topic are necessary to fill the needs and improve the subject. A familiar phenomenon in the literature of composite structures is the non-uniform distribution of stresses along the width of the concrete slab, called shear lag. In the analysis and design of composite beams, deflections, stresses, and strengths are typically obtained by utilizing the concept of effective width, in which shear lag effects are accounted for indirectly, by replacing the actual slab width by an appropriately reduced width. Without having exact numerical analysis for design, it is necessary that the design codes provide simplified methods for evaluating this effective width, minimizing losses of accuracy. In this work, numerical procedures for the evaluation of effective width, found in the specialized literature, were studied and implemented in the mathematical finite element model available in CEMACOM/PPGEC/UFRGS. This computational code is capable of representing the behavior of steel-concrete composite beams and is capable of capturing the shear lag effect. The response of a single span composite beam with fixed ends, representing an intermediate span of a continuous girder bridge, subject to long-term loading, and considering both rheological phenomena of concrete, such as creep and shrinkage, besides the non-linear behavior due to cracking, is obtained and compared to the stipulated formulas in the main code provisions and in the developed methodologies by some researchers. Potential failures in the current design codes were evidenced, requiring additional experimental and numerical parametric studies to prove the results.
143

Assessment of a nearshore modular flap-type wave energy converter

Wilkinson, Laurie Fletcher January 2018 (has links)
This thesis presents an assessment of a modular flap-type wave energy converter. Comparisons are made to an equivalent width rigid device. All quoted relative difference results here use the rigid device as the reference point. The variables that are evaluated are the power capture and surge and yaw foundation loads. The power capture is evaluated at both module and device level, while the foundation loads are assessed just at the device level. The investigation is carried out through testing of a 30th scale physical model in a wave tank. A key output from the work is the development of the physical model. The model consists of six flap modules, mounted on a common base structure. Each module contains a highly controllable and compact power take off system. The devices are tested in a range of conditions, primarily consisting of regular waves of different period and direction. The damping strategy employed is the simplest approach available, setting the achievable damping level on each module to be the same. For the modular device in head-on regular waves, the results show that the power capture increases significantly moving from the outer to the central modules. On average, the central pair of modules produce 68 % of the total mean power, the inner modules 25 % and the outer modules only 7 %. Between the devices, it is shown that the power captures in head-on waves are similar, with a mean relative difference of -3 %, with +/-5 % uncertainty. Thus, no statistically significant change in power capture is shown. In off-angle waves, the mean relative difference is –1 %, with +/-4 % uncertainty. However, for the highest wave direction that was tested in, 27.5 degrees, the modular device outperforms the rigid flap, by 10 %, with uncertainty of +/-1 %. The surge foundation loads are shown to be very similar for the two devices - in head-on waves, the mean relative difference is +2 %. Depending on the level of applied damping, however, significant differences in the yaw foundation loads are shown. Using damping where the power capture is maximised, the yaw loads increase by a mean of 10 %; using damping where the power to load ratio is instead maximised, the modular yaw loads are 26 % lower. Finally, the economics of the power production is estimated through division of the power capture with a cost metric, the foundation loads. While this does not provide a full techno-economic assessment, it effectively captures the interdependency of the power capture and foundation loads for the devices. The mean relative differences in the power per load ratios of the devices are found to be similar across the wave conditions. In the head-on waves, the differences are between –8 and –0.4 %, depending on damping strategy; in the off-angle waves, the differences are between –6 and +10 %. For both sets of wave conditions, the modular flap performs better when the damping is set to maximise the ratio of power capture to foundation loads. The work concludes that the modular and rigid devices produce power and experience foundation loads at similar levels in head-on waves. Given the high power capture efficiency, nearshore location, simple mode of operation and high survivability of the flap-type WEC, this suggests that the modular device is a viable stand-alone concept. The work also finds that in off-angle waves, some benefits can be achieved with an appropriately damped modular system, notably in improved power capture and reduced yaw foundation loads. These could reduce the sensitivity that flap-type devices have in off-angle waves and allow expansion of the width and hence capacity of machines. Further work should extend the wave conditions tested in, by using more irregular and directional waves, and investigate more damping strategies and geometries. Economic assessment should also be carried out.
144

Vliv hnojení a organizace porostu kukuřice (šířky řádků) na výnos silážní kukuřice

KRUML, Martin January 2016 (has links)
The aim of my thesis was to compare the yields of silage maize (Zea mays L.) at different width lines at fertilization under the heel and at different calibration individuals per ha. For this comparison, I founded two attempts. The first trial, which concerned a drill spacing and fertilization under the heel, I founded the company in ZKS AGRO Zahořany. When you first try, I used four experimental plots, each plot'm sends corn in four ways. Every site I sent to different widths and lines on the 37.5 cm, 45 cm and 75 cm, and the fourth land, I also sent to 75 cm but no fertilizer under the heel. Then I watched all the land, and eventually I compared all the land maize yield in green stuff. For the three parcels I compared the yield depending on the width of rows and rows for seeding with a width of 75 cm, we compared the yield depending on the fertilizer under the heel. The second attempt, which concerned the size of the seed rate, I founded the company in ZOD Mrákov. In this experiment, I sewed maize on one plot. On this land, I imposed a 6 plots. On these plots, I used 3 sizes calibration and 85000, 95000 and 105000 individuals / ha. I also 3 plots, these calibrating, sent to the line width of 37.5 cm, and the remaining three plots on the line width of 75 cm. These plots I watched the whole vegetation period and finally I compared the yields from each plot of land in the green stuff.
145

Importance of Concentrated Flow Paths in Agricultural Watersheds of Southern Illinois

Shrestha, Prabisha 01 May 2017 (has links)
Field scale research shows concentrated flow paths (CFPs) are prevalent in agricultural watersheds. They are an important source of soil erosion in cropland and significantly contribute to the transport and delivery of agricultural pollutants such as sediment and nutrients to nearby water resources. High resolution LiDAR data have enabled the investigation of the prevalence of concentrated flow at a large geographic extent. This study focused on identifying CFPs in 389 agricultural fields in Jackson County in southern Illinois and estimating the contribution of the CFPs to drainage of the fields. Addressing the lack of literature on factors influencing CFP characteristics, this study also investigates various topographical and soil factors that influence CFP development. LiDAR derived DEMs with a cell resolution of 3 meters were used to identify areas of flow concentration and delineate a drainage basin of each CFP using the Hydrology tools in the Spatial Analyst toolbox in ArcMap 10.3.1. Information on the topographical and soil characteristics were obtained from the DEMs and SSURGO database using the Soil Data Viewer 6.2 extension for ArcMap. Multiple regression analysis in SAS v. 9.4 was used to identify factors influencing CFP characteristics, while CART analysis in R v. 3.3.1 was conducted to detect linear dependencies among predictor variables. An average of 5 CFPs per agricultural field were observed in the study area with a minimum of 0 and maximum of 17 CFPs, but only two fields had no CFPs indicating a high prevalence of CFPs throughout the study area. The mean percent of field area drained by CFPs was estimated to be 81 percent with minimum of 36 percent and ii maximum of 100 percent. The majority of the fields, 85 percent, had more than 70 percent of their area drained by CFPs. Statistically significant regression equations were found for all CFP characteristics with slope, LS factor, K factor and organic matter as the factors influencing CFP characteristics. However, the factors only explained 2 to 22 percent of variation observed. Both multiple regression and CART analysis indicated slope as the most important influencing factor. Variation in CFP characteristics followed regional trends with higher values in the floodplain region and lower values in the rough hills region suggesting residual variation could be explained by other environmental factors along with topographical and climatological factors which were not included in the study. Results from this study highlight the prevalence of CFPs at a regional scale and their substantial contribution to field drainage identifying a need for research in quantifying the impacts of CFP on soil loss and water quality. This study also reports a need of future research to identify important factors controlling CFP formation and development that could help build empirical and physical models to accurately predict CFP locations and morphology. Such information could be useful in designing and targeting conservation practices that protect both soil health and water quality.
146

Estudo da largura efetiva de vigas mistas de aço-concreto em carregamento de serviço : método dos elementos finitos versus códigos de projeto / Estudo da Largura Efetiva de Vigas Mistas de Aço-Concreto em Carregamento de Serviço: Método dos Elementos Finitos versus Códigos de Projeto

Reginato, Lucas Henrique January 2017 (has links)
Com a crescente utilização de vigas mistas de aço e concreto em obras civis e devido à insuficiência de estudos relativos ao seu comportamento estrutural, investigações aprofundadas são necessárias para suprir as carências e aperfeiçoar o tema. Um fenômeno familiar na literatura de estruturas mistas é a distribuição não uniforme de tensões ao longo da largura da laje de concreto, denominado shear lag na literatura inglesa. Na análise e projeto de estruturas compostas, deflexões, tensões e resistência são tipicamente obtidas utilizando-se o conceito de largura efetiva, na qual o efeito shear lag é contabilizado indiretamente, substituindo a largura real da laje, por uma largura apropriadamente reduzida. Sem dispor de análises numéricas exatas para o dimensionamento prático, é necessário que códigos normativos forneçam métodos simplificados para a avaliação da largura efetiva minimizando perdas de precisão. Diante disso, no presente trabalho, procedimentos numéricos para a avaliação da largura efetiva, encontrados na literatura técnica, foram estudados e implementados ao modelo matemático em elementos finitos disponível no CEMACOM/PPGEC/UFRGS, capaz de representar com confiabilidade estruturas mistas. Comprovando-se a eficácia do modelo numérico em captar o efeito do shear lag, a resposta de uma viga mista biengastada, representando um vão intermediário de uma ponte contínua, submetida a um carregamento em longo prazo, e considerando-se os fenômenos reológicos do concreto de fluência e retração, além do comportamento não-linear devido a fissuração, é obtida e comparada à fórmulas estipuladas nas principais normas de projeto e em metodologias desenvolvidas por pesquisadores. Falhas potenciais nos códigos de projeto atuais foram evidenciadas, necessitando-se de adicionais estudos paramétricos experimentais e numéricos para a comprovação dos resultados. / With the increasing use of steel-concrete composite beams in bridges and buildings more investigations related to this topic are necessary to fill the needs and improve the subject. A familiar phenomenon in the literature of composite structures is the non-uniform distribution of stresses along the width of the concrete slab, called shear lag. In the analysis and design of composite beams, deflections, stresses, and strengths are typically obtained by utilizing the concept of effective width, in which shear lag effects are accounted for indirectly, by replacing the actual slab width by an appropriately reduced width. Without having exact numerical analysis for design, it is necessary that the design codes provide simplified methods for evaluating this effective width, minimizing losses of accuracy. In this work, numerical procedures for the evaluation of effective width, found in the specialized literature, were studied and implemented in the mathematical finite element model available in CEMACOM/PPGEC/UFRGS. This computational code is capable of representing the behavior of steel-concrete composite beams and is capable of capturing the shear lag effect. The response of a single span composite beam with fixed ends, representing an intermediate span of a continuous girder bridge, subject to long-term loading, and considering both rheological phenomena of concrete, such as creep and shrinkage, besides the non-linear behavior due to cracking, is obtained and compared to the stipulated formulas in the main code provisions and in the developed methodologies by some researchers. Potential failures in the current design codes were evidenced, requiring additional experimental and numerical parametric studies to prove the results.
147

Verificação experimental da largura colaborante em mesas de lajes nervuradas. / Experimental verification the cooperating width in flange waffle slabs.

Paulo José Barreto Teixeira 26 October 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta um estudo experimental para determinação da largura colaborante em mesas de lajes nervuradas de concreto armado. Esta largura é definida comumente utilizando-se as recomendações contidas nas diversas normas e procedimentos já consagrados de estruturas de concreto armado. Visando a determinação da largura da mesa que efetivamente contribui na capacidade resistente da seção de lajes nervuradas, foram instrumentados e ensaiados modelos que buscaram reproduzir faixas de nervuras e painéis de laje. As faixas possuíam dimensões reais de duas nervuras principais, enquanto as lajes reproduziam painéis em escala reduzida (1:2). Em parte dos modelos, foram inseridos extensômetros de resistência elétrica nas armaduras e no concreto, além de transdutores para verificação das flechas. Foram calculadas as larguras a partir das curvas de tensões e flechas verificadas experimentalmente. Verificou-se, também, a influência da presença de tubulação embutida ao longo da mesa das faixas de laje. / This paper presents an experimental study to determine the cooperating width in flange waffle slabs of reinforced concrete. This width is usually established through the recommendations in the various rules and procedures already defined for reinforced concrete structures. In order to determine the width of the flange that effectively contributes to the ability of the resistant section slabs, models that sought to play tracks of panels and ribbed slab were tested and instrumented. The strips had two actual dimensions of main ribs, while the slab panels were reproduced on a reduced scale (1:2). In some of the models, electrical resistance strain gages were inserted in the reinforcement and in the concrete, and the arrows were checked by the transducers. The Widths were calculated from the curves of stress and the arrows were experimentally verified. The influence of a pipe embedded along the tracks of the flange slabs were also taken into consideration.
148

Avaliação da influência de variáveis na produção de batentes de painel EGP de Pinus taeda / Evaluation of the influence of variables in the production of door frame of Edge Glued Wood Panel of Pinus taeda

Dias, Romulo Rezende [UNESP] 19 February 2016 (has links)
Submitted by Romulo Rezende Dias null (romulordias@yahoo.com.br) on 2016-03-17T20:12:40Z No. of bitstreams: 1 Dissertação Romulo Rezende Dias corrigida.pdf: 4489690 bytes, checksum: 9af841b8b53dd7ecfeee3773848e7168 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-03-21T18:27:40Z (GMT) No. of bitstreams: 1 dias_rr_me_guara.pdf: 4489690 bytes, checksum: 9af841b8b53dd7ecfeee3773848e7168 (MD5) / Made available in DSpace on 2016-03-21T18:27:40Z (GMT). No. of bitstreams: 1 dias_rr_me_guara.pdf: 4489690 bytes, checksum: 9af841b8b53dd7ecfeee3773848e7168 (MD5) Previous issue date: 2016-02-19 / O uso de madeira de pinus na construção civil é cada vez maior e saber trabalhar suas características, vantagens e desvantagens é essencial para o sucesso do produto. O presente trabalho tem por objetivo estudar a influência da largura das lamelas e do arranjo físico dos anéis de crescimento em painéis de madeira de Pinus taeda coladas lateralmente (EGP) utilizados na fabricação de batentes, seguindo as exigências da ABNT-NBR 15.930 (2011), a fim de determinar a melhor combinação para o melhor desempenho físico do produto. Para tanto, trabalhou-se com o fatorial completo para dois fatores e quatro níveis, sendo i. largura das lamelas de 32 mm, 56 mm, 75 mm e 112mm; e ii. arranjo dos anéis: lamelas radias, lamelas tangenciais, lamelas cruzadas e lamelas com emendas de topo tipo finger joint. Os 48 corpos de prova (03 para cada combinação) de batente de EGP com 2120 x 220 x 32mm, com teor de umidade entre 8% e 12% e densidade aparente entre 400 kg.m-3 e 600 kg.m-3 foram produzidos numa indústria madeireira da cidade de Sengés/PR. Utilizou-se a análise estatística de variância (ANOVA) para investigar a influência dos fatores e suas interações nas seguintes respostas: aspecto visual, variação da umidade, variação da densidade, variações dimensionais de largura e espessura e desvios de forma (empenamento: encurvamento, arqueamento e encanoamento). Os resultados mostraram que os dois fatores e suas interações exerceram influência com nível de significância de 1% sobre os desvios de forma. Os melhores resultados foram para painéis produzidos com lamelas de 32 mm e 56 mm, com arranjo cruzado ou radial. As demais respostas não foram influenciadas de forma significativa pelos fatores e suas interações. / The use of pine wood is increasing and for the success of its products it is essential to have the know-how to work its features, advantages and disadvantages. The objective of this study is to evaluate the influence of batten widths and the physical arrangement of growth rings in Edge Glued Panel of Pinus taeda used in the manufacture of door frames, according the requirements of ABNT-NBR 15.930 (2011) to determine the best combination for better physical performance of the door frame. Experimental tests considered the full factorial method using two factors and four levels, with batten widths of 32mm, 56mm, 75mm and 112mm; and arrangement of the growth rings: radial, tangential, crossed and plates with top amendments type finger joint. The 48 samples (03 from each combination), with 2120 x 220 x 32 mm, with a moisture content between 8% and 12% and an apparent density between 400 kg.m-3 and 600 kg.m-3 were produced in a wood factory in Sengés/PR/Brasil. The statistical analysis of variance (ANOVA) was used to investigate the influence of the factors and their interactions in the following responses: visual appearance, moisture content variations, density variations, dimensional variations in width and thickness and deviations in shape (warping: bending, curving and curling). The results showed that both factors and their interactions exerted influence with a significance level of 1% on the deviations of form. The best results were to EGP produced with batten widths of 32 mm and 56 mm, with radial or crossed arrangement. The factors and their interactions did not significantly influence the other answers.
149

PWM techniques for control of dual-inverter supplied six-phase drives

Patkar, Fazlli January 2013 (has links)
Among the different multiphase ac drive solutions, one of the most widely reported in the literature is the six-phase machine. The machines can be realised into two different configurations, symmetrical and asymmetrical. For the symmetrical configuration, the stator winding consists of two sets of three-phase windings that are spatially shifted by 60 degrees where spatial displacement between any two consecutive phases is the same and equal to 60 degrees. For the asymmetrical configuration, the two sets of three-phase windings are spatially shifted by 30 degrees. As a result, the spatial shift between consecutive phases becomes non-equidistant. In this thesis, modulation techniques for both symmetrical and asymmetrical six-phase machines are investigated. The machines are configured in open-end winding configuration where both ends of the stator winding are connected to separate isolated inverters in a topology known as dual-inverter supply. Compared to conventional single-sided supply topology where one end of the winding is connected to an inverter while the other side is star-connected, some additional benefits are offered by the dual-inverter supply topology. First, fault tolerance of the drive is improved, since the supply is realised with two independent inverters. In case one of the inverters is faulted, the other can continue to provide power to the machine. Second, the same phase voltages can be achieved with half the dc-link voltages on the two inverter inputs compared to the single-sided supply, which can be useful in applications such as electric and hybrid electric vehicles and medium sized ships, where the dc voltage levels are limited. Further, due to the nature of the topology, additional diodes and capacitors like in the Neutral Point Clamped (NPC) and Flying Capacitor (FC) VSIs are not required. The latter results in a further advantage - capacitor voltage balancing techniques are not required. Two pulse width modulation (PWM) techniques for control of the dual-inverter supplied six-phase drives are proposed in this thesis. The first is a reference sharing algorithm where the inverters are modulated using reference voltage that is shared equally and unequally between the two modulators. For both symmetrical and asymmetrical six-phase drives, a better performance, in term of total harmonic distortion (THD) of phase voltage is obtained when the reference is shared unequally between the two modulators. The second technique is carrier-based modulation where the modulation of the two inverters is determined by the disposition of the carrier signals. Three variations of carrier signals disposition are investigated namely; the phase disposition (PD-PWM), alternate phase opposition disposition (APOD-PWM) and phase-shifted PWM (PS-PWM). For the symmetrical six-phase drive, the best phase voltage and current THDs are obtained using APOD-PWM while for asymmetrical six-phase drive, the APOD-PWM produces the worst current THD despite having the best voltage THD among the three methods. All the developed modulation techniques are analysed using simulations and experiments undertaken using a laboratory prototypes. The waveforms and spectra of phase voltage and load current obtained from the simulation and experimental works are presented in this thesis together with the THD of both the voltage and current over entire linear modulation range.
150

Desempenho de uma distribuidora a lanço com dois tipos de produtos aplicados em diferentes posições de aletas nos discos

Hachuy, Leandro [UNESP] 05 September 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-05Bitstream added on 2014-06-13T19:52:23Z : No. of bitstreams: 1 hachuy_l_me_botfca.pdf: 561032 bytes, checksum: e2112f64e18c75e1470be1df52d15a35 (MD5) / Dentre as operações preliminares para a boa condução de uma cultura instalada a campo está a calagem, que visa corrigir as propriedades químicas do solo e também a adubação a lanço com nitrogênio, tradicionalmente utilizada em cobertura, e hoje numa nova tendência, em pré-plantio. Não se tem domínio ou informações confiáveis sobre a maioria das máquinas disponíveis no mercado brasileiro referentes à qualidade da aplicação realizada por esses equipamentos, bem como a sua largura efetiva de trabalho. Essa largura é determinada como função de uma regularidade mínima na dosagem, obtida a partir da sobreposição com passadas adjacentes. A determinação da largura de trabalho ou largura efetiva é definida a partir de ensaios padronizados. O experimento foi conduzido a campo, no ano de 2008, na Fazenda Experimental Lageado da Faculdade de Ciências Agronômicas – Unesp- Campus de Botucatu SP, em solo classificado como Nitossolo Vermelho distroférrico.O presente trabalho teve como objetivo principal avaliar o desempenho de um distribuidor a lanço na aplicação de calcário e uréia com 4 diferentes posições de aletas nos discos em uma mesma velocidade de deslocamento do trator. Os tratamentos foram os seguintes: T1- calcário – largura de distribuição média e direcionamento do produto intermediário; T2- calcário – largura de distribuição menor e direcionamento do produto mais para o centro; T3- calcário – largura de distribuição maior e direcionamento do produto mais para as extremidades; T4- calcário – ajuste de somente duas aletas em ângulos diferentes das demais; T5- uréia – ajuste de somente duas aletas em ângulos diferentes das demais; T6- uréia – largura de distribuição média e direcionamento do produto intermediário; T7- uréia – largura de distribuição menor e direcionamento do produto mais para o centro;... / Among the preliminary to the smooth conduct of a culture installed the field is set, seeking to correct the chemical properties of soil and and also the fertilizing to throw, traditionally used in covering, and today in a new tendency, in daily pre-planting. There is no field or reliable information on the majority of machines available in the Brazilian market concerning the quality of the application made by such equipment as well as its effective width of work. This width is determined as a function of the regular minimum strength, obtained from the overlap with adjacent past. The determination of the width of work or effective width is defined from standardized tests. Liming, in most cases is done with machines called specialized applications of fertilizers and corrective. The machines are divided as the mechanism doser in centrifugal and continuous thread. Quantities ideals are obtained through specific formulas. The experiment was carried out in 2008, on the the Experimental Farm Lageado of São Paulo State University in Botucatu, on soil classified as Dystroferric Red Nitosol.This study aimed to evaluate the performance of primary distributor with a haul in the application of lime and urea with 4 different positions of fins on the disks in the same speed of displacement of the tractor. The treatments were: T1-lime - average width of distribution and product direction of the intermediary, T2-lime - width of distribution and lower direction of the product more to the center; T3-lime - width and direction of greater distribution of the product more to the extremities; T4-lime - adjustment of only two fins at different angles of the other; T5-urea - adjustment of only two fins at different angles of the other; T6-urea - average width of distribution and product direction of the intermediary; T7 -urea - width of distribution and lower direction of the product more to the center;... (Complete abstract click electronic access below)

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