Spelling suggestions: "subject:"farm machinery"" "subject:"arm machinery""
1 |
Agricultural machinery selection and scheduling of farm operationsSaadoun, Tahar January 1989 (has links)
The procedure of calculating annual machinery ownership costs from the discounted cash flows of the mortgaged capital cost, the repair and insurance charges and the resale income is extended to include the effect of loan rate and loan period on interest charges, the effect of capital allowances taking account of the actual balancing charges at the end of the period of ownership, and the effect of tax relief on the interest charges, repair costs and insurance premiums. The concept of marginal holding cost is applied to determine the optimum ownership period. The selection of tractor- plough combinations is based on the prediction of soil characteristics such as moisture content, strength, and workability, all of which influencing the assessment of plough draught and tractor power. A number of filters are used to select the appropriate and realistic tractor /implement combinations with different sizes of fully mounted plough depending on the draught, and the speed of each selected gear of the tractor. For each acceptable combina- tion of tractor and fully mounted plough determined, the costing routine is used to calculate the annual costs. The branch and bound algorithm is suitable for mixed integer solutions to the farm machinery selection problem. Machinery sets are selected simultaneously with the chosen cropping pattern on a given land area. Machinery sets are matched correctly to the tractor sizes. Four sizes of tractor are available (45 kW, 61 kW, 74 kW and 94 kW,. Field operations take place in discrete time periods during which available work days are predicted from soil type and weather records for the specific site. Cereal and root crops are distinguished by optimum sowing and harvesting date. Discrete time periods are defined in relation to these optimal dates and give rise to overlapping operations for different crops. The calculation of probability levels for available work days when operations are subject to different criteria is discussed. A single arbitrary value of 75% probability for available work days is adopted in the linear programming model for the main part of the study. Two stage processes are used to simulate available work days in each time period. The patterns generated converge on the relative frequency pattern laid down by the generating process. The range of experience is wider than that contained in the short series of 24 years historical data. The simulation model generates results suitable for stochastic dominance ranking. In a simulation experiment on a 250 ha arable farm cropping cereals and potatoes, alternative solutions are obtained by integer linear programming, the solutions being ranked according to gross revenue. Annual costs of operating farm machinery are derived from a separate costing algorithm based on the annual hours of use which are determined by the size of the task and not by the sequence of work days. After deducting the annual costs of machinery operation, the cumulative net revenue curves cross and second order stochastic dominance ranking is used to identify the optimum (maximum profit) solution. The current study demonstrates the viability of the analytical procedures but further work is now required to reduce the computing time involved for the complete machinery selection procedure. Meanwhile, a commercial software package is prepared on the calculation of annual machinery ownership costs.
|
2 |
Desenvolvimento e avaliação do desempenho de um equipamento para ensaio dinâmico de rodado agrícola individualNagaoka, Alberto Kazushi [UNESP] 05 February 2001 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:39Z (GMT). No. of bitstreams: 0
Previous issue date: 2001-02-05Bitstream added on 2014-06-13T20:22:38Z : No. of bitstreams: 1
nagaoka_ak_dr_botfca.pdf: 2279820 bytes, checksum: 149eef5c845342281d3c5d15503e3456 (MD5) / O principal objetivo deste trabalho foi desenvolver, instrumentar e avaliar o desempenho de um equipamento para ensaio de pneus agrícolas acoplado a um trator, acionado pela sua tomada de potência, com a finalidade de ensaiar dinâmica e individualmente pneus em condição de campo e avaliar o efeito da passagem do pneu no solo. O equipamento foi desenvolvido no Núcleo de Ensaios de Máquinas e Pneus Agrícolas (NEMPA), pertencente ao Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas da Universidade Estadual Paulista (UNESP), situado no município de Botucatu. Os dados obtidos nas calibrações e nos ensaios foram ajustados pelo método de regressão e os dados do experimento foram analisados considerando-se o delineamento experimental em blocos, no esquema de parcelas subdivididas, tendo nas parcelas os pneus e nas subparcelas as cargas, com cinco repetições. Os valores de índice de cone do solo foram analisados considerando-se o delineamento experimental em blocos, no esquema de parcelas subsubdivididas, e tendo na parcela os pneus, na subparcela as cargas e na subsubparcela as camadas, com cinco repetições. Os resultados do experimento foram interpretados estatisticamente, por meio da análise de variância, adotando-se o nível de significância de 5% e pelo teste de comparação de médias de Tukey. Foram realizados ensaios com variações de velocidades de 0 a 14 km/h, patinagens de 3% a 34%, diâmetros de pneus de 1250 mm a 1722 mm, larguras de pneus de 500 mm a 602 mm e cargas verticais de 5.000 N a 24.000 N. Para estes valores não foram observados danos ao equipamento. O comprimento mais adequado da parcela para os ensaios de campo foi de 20m com freqüência de aquisição de 1Hz. O equipamento permitiu avaliar o desempenho dinâmico de pneus, em condições de solo agrícola, pista asfáltica e comparar diferentes tipos de pneus... / The main objective of this research was to develop, to instrument and to evaluate the performance of a Single Wheel Testing Equipment, linked to a tractor and motioned by the power take off (PTO) with the purpose of dynamically testing individual tires in field and laboratory conditions. The equipment was developed in Agricultural Machinery and Tire Testing Center (NEMPA), Rural Engineering Department of Agronomic Science College, São Paulo State University (UNESP), Botucatu County. The obtained calibration and test data were adjusted using regression method and the experiment data were analyzed considering an experimental design in split plot blocks, with the tire in the parcels and the load tire in the subparcels, with five repetitions. The cone index values were analyzed considering the same experimental design, with the tire in the parcels, the tire load in the subparcels, and the soil layers in the subsubparcels, with five repetitions. The experiment results were statistically interpreted by means of variance analysis, adopting 5% of significance level and using Tukey average test comparison. The tests were realized varying the forward speed from 0 to 14 km/h, the slip from 3% to 34 %, the tire diameter from 1,250 mm to 1,722 mm, the tire width from 500 mm to 602 mm, and the tire loads from 5,000 to 24,000 N. The device worked very well and it was not observed damages or failures for all tested situations. The most adequate parcel length obtained on the field tests was 20 m, using the acquisition frequency of 1 Hz. The equipment permitted to evaluate tire dynamic performance on agricultural field conditions, asphalt track and to compare different tire types as a function of inflation pressure, slip, rolling radius, and tire load. The equipment evaluated individuality the tested tire and have an eletronic date colect system, providing agility and practicity in the tests...(Complete abstract, click electronic access below)
|
3 |
MODELING ANNUAL AND QUARTERLY U.S. FARM TRACTOR SALESKylie M O'Connor (8752446) 23 April 2020 (has links)
Farm machinery is a vital input for production agriculture and, as a result, is a significant part of the agricultural economy. Despite its great importance, there has been relatively little academic analysis on the driving forces behind farm machinery sales over the past several decades. The studies that do evaluate farm machinery sales all do so regarding annual sales despite shorter-term sales data being available. These previous studies primarily use traditional macroeconomic variables, tailored to the agricultural industry, to explain farm machinery sales. Recently, with the creation of the Ag Economy Barometer Survey in October 2015, farmer sentiment data is being collected. Studies using consumer sentiment data to evaluate consumer demand have found sentiment data useful when including it in demand models, especially for consumer durable goods. This study evaluates farm machinery sales, specifically two-wheel-drive tractors with 100 horsepower or higher, using both traditional macroeconomic variables and farmer sentiment data. The evaluation begins by looking at annual tractor sales from 1978 to 2019 using machinery prices, prices received for outputs, prices paid for inputs, lagged net farm income, interest rates for loans specifically for farm machinery, farm assets, and the number of acres harvested. The annual models are used to derive elasticities with respect to farm tractor sales, and the quantity demanded is most responsive to changes in machinery prices, the number of acres harvested, prices received for crops and livestock, and the level of farm assets. Out-of-sample estimations aids in evaluating the forecasting power of the models with the best statistical fit. The model with the best out-ofsample performance forecasts 2020 sales of farm tractors with 100 HP and above using various assumptions for agricultural economic conditions in 2020. The model estimates a record low in tractor sales dating back to 1978. The annual models are then re-estimated using quarterly data spanning from 2009 to 2019. The quarterly models have less statistical fit than their annual counterparts. This reduced model performance is likely due to the seasonal nature of farm tractor sales and that some of the explanatory variables are only updated on an annual basis, limiting their ability to capture the seasonal variations. Finally, the quarterly models are estimated again to include farmer sentiment data. At the time of the study, only 17 quarterly observations of farmer sentiment data had been collected, significantly limiting the evaluation. The limited number of observations results in an inconclusive outcome regarding the explanatory power of farmer sentiment data.
|
4 |
Desenvolvimento e avaliação do desempenho de um equipamento para ensaio dinâmico de rodado agrícola individual /Nagaoka, Alberto Kazushi. January 2001 (has links)
Orientador: Kléber Pereira Lanças / Banca: Ulisses Rocha Antuniassi / Banca: João Eduardo Guarnetti Santos / Banca: Marcos Milan / Banca: Haroldo Carlos Fernandes / Resumo: O principal objetivo deste trabalho foi desenvolver, instrumentar e avaliar o desempenho de um equipamento para ensaio de pneus agrícolas acoplado a um trator, acionado pela sua tomada de potência, com a finalidade de ensaiar dinâmica e individualmente pneus em condição de campo e avaliar o efeito da passagem do pneu no solo. O equipamento foi desenvolvido no Núcleo de Ensaios de Máquinas e Pneus Agrícolas (NEMPA), pertencente ao Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas da Universidade Estadual Paulista (UNESP), situado no município de Botucatu. Os dados obtidos nas calibrações e nos ensaios foram ajustados pelo método de regressão e os dados do experimento foram analisados considerando-se o delineamento experimental em blocos, no esquema de parcelas subdivididas, tendo nas parcelas os pneus e nas subparcelas as cargas, com cinco repetições. Os valores de índice de cone do solo foram analisados considerando-se o delineamento experimental em blocos, no esquema de parcelas subsubdivididas, e tendo na parcela os pneus, na subparcela as cargas e na subsubparcela as camadas, com cinco repetições. Os resultados do experimento foram interpretados estatisticamente, por meio da análise de variância, adotando-se o nível de significância de 5% e pelo teste de comparação de médias de Tukey. Foram realizados ensaios com variações de velocidades de 0 a 14 km/h, patinagens de 3% a 34%, diâmetros de pneus de 1250 mm a 1722 mm, larguras de pneus de 500 mm a 602 mm e cargas verticais de 5.000 N a 24.000 N. Para estes valores não foram observados danos ao equipamento. O comprimento mais adequado da parcela para os ensaios de campo foi de 20m com freqüência de aquisição de 1Hz. O equipamento permitiu avaliar o desempenho dinâmico de pneus, em condições de solo agrícola, pista asfáltica e comparar diferentes tipos de pneus...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objective of this research was to develop, to instrument and to evaluate the performance of a Single Wheel Testing Equipment, linked to a tractor and motioned by the power take off (PTO) with the purpose of dynamically testing individual tires in field and laboratory conditions. The equipment was developed in Agricultural Machinery and Tire Testing Center (NEMPA), Rural Engineering Department of Agronomic Science College, São Paulo State University (UNESP), Botucatu County. The obtained calibration and test data were adjusted using regression method and the experiment data were analyzed considering an experimental design in split plot blocks, with the tire in the parcels and the load tire in the subparcels, with five repetitions. The cone index values were analyzed considering the same experimental design, with the tire in the parcels, the tire load in the subparcels, and the soil layers in the subsubparcels, with five repetitions. The experiment results were statistically interpreted by means of variance analysis, adopting 5% of significance level and using Tukey average test comparison. The tests were realized varying the forward speed from 0 to 14 km/h, the slip from 3% to 34 %, the tire diameter from 1,250 mm to 1,722 mm, the tire width from 500 mm to 602 mm, and the tire loads from 5,000 to 24,000 N. The device worked very well and it was not observed damages or failures for all tested situations. The most adequate parcel length obtained on the field tests was 20 m, using the acquisition frequency of 1 Hz. The equipment permitted to evaluate tire dynamic performance on agricultural field conditions, asphalt track and to compare different tire types as a function of inflation pressure, slip, rolling radius, and tire load. The equipment evaluated individuality the tested tire and have an eletronic date colect system, providing agility and practicity in the tests...(Complete abstract, click electronic access below) / Doutor
|
5 |
The Cost of Owning and Operating Farm Power and Machinery Used in Tillage Operations on Diversified Farms in Selected Areas of Utah, 1960Phillips, Clynn 01 May 1962 (has links)
A current problem facing fanners is, how much shouls they mechanize their farm perations? Ae the relative price and productivity of factors change farmers usually have to adjust their operations to assure maximum profits. Technological advances often change the relative productiveness and the price of machinery. These changes have caused the progressive farmer to continually review his farm organization and make adjustments in levels of factor use. If he is to produce at maximum profits it is necessary that his machinery investment be in proper adjustment with other resources.
|
6 |
Geographies of Competitive Advantage: An Examination of the US Farm Machinery IndustryDrake, Dawn M 01 May 2011 (has links)
Many explanations of competitive advantage view place as a secondary factor. Organizational studies models tend to be considered aspatially, yet most are inherently geographic. It is important to consider the impact that geography has on the success or failure of an individual firm or a sector. This dissertation examines how location impacts the US farm machinery industry through an empirical analysis of Porter’s Theory of Competitive Advantage. Contributing to this empirical test are other bodies of literature including models for headquarters and research and development siting, product life cycle theory, industry life cycle theory, and green technologies as a driver of competitive advantage.
The US farm machinery industry is composed of three firms: Deere and Company, Case New Holland, and the Allis-Gleaner Corporation. Theory-elaborating case study methodology, informed by archival data, publically available documents, trade show reconnaissance, and plant tours, coupled with map and content analysis allows for a deeper understanding of how geography impacts competitive advantage in the sector.
Comparing findings from these geographic case studies to Porter’s results led to a new understanding of competitive advantage for mature manufacturing in a globalized economy. Previous analysis found Porter’s single diamond, which focuses on local conditions for competitive advantage, most appropriate for explaining mature industries in advanced market economies. This study found, however, that as mature industries increasingly pursue a global focus, a double diamond model, which takes into account both local and global conditions for competitive advantage, is more appropriate, even in an advanced economy.
This research also found that, much like second-tier cities are desirable for headquarters and research and development siting, second-tier countries (that can provide high-skill labor at lower prices) are increasingly attractive for manufacturing operations. The need for modifications to product life cycle theory that take into account the impact of these countries as well as the effects of nationalism on manufacturing decisions in mature economies were also uncovered by this dissertation.
This research demonstrates the continued importance of place to understanding competitive advantage, not only in the US farm machinery industry, but generally for mature manufacturing as a whole.
|
7 |
Factors affecting the annual unit sales volume of combines in the United StatesSmith, Benjamin January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / In the United States, accurately predicting the agricultural industry’s future demand for new farm machinery is a complicated, challenging and ever-changing issue. To compound the matter; as the size of large farm machinery continues to increase, the annualized sales volume is decreasing over time. This thesis also finds that recent mandates applicable to the Environmental Protection Agency (EPA) diesel engine emission compliance and the Internal Revenue Service (IRS) Section 179 tax code may help with forecasting the demand for farm machinery on an annual basis.
This thesis evaluates factors that affect the annual unit demand of combines in the United States. Due to the lack of published literature on this specific topic, a survey of John Deere dealership sales professionals who have had recent experience selling new combines to farmers was used. This perspective brings to light factors that impact industry demand for new combines. This study results in an empirical regression model with independent variables based on the survey results. A thorough understanding of the independent variables can aid in predicting the future demand for combines.
This work indicates that forty years of historical data proves to provide enough variability such that statistically significant variables are identified to accurately predict future sales. Statistically significant factors that affect the annual unit sales volume of combines in the United States include: Interest Rate, Net Cash Income, IRS Section 179 Tax Code, Planted Acres and Combine Capacity. Future industry demand is predicted by applying forecasted estimates to the model’s applicable independent variables.
|
8 |
Semeadora-adubadora: mecanismos de corte de palha e cargas verticais aplicadasSilva, Paulo Roberto Arbex [UNESP] 23 February 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:34Z (GMT). No. of bitstreams: 0
Previous issue date: 2007-02-23Bitstream added on 2014-06-13T18:42:22Z : No. of bitstreams: 1
silva_pra_dr_botfca.pdf: 1456946 bytes, checksum: 8d38e454a4f1a63e94c67416addedfec (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Para o sistema de semeadura direta obter o sucesso desejado deve haver a seleção adequada dos componentes das semeadoras-adubadoras, entre os quais os mecanismos de corte de palha. Além disso, o estudo das características do solo e da cultura de cobertura implantada na área são importantes itens que definem a eficiência destas máquinas. Este trabalho teve como objetivo avaliar o desempenho dos mecanismos de corte de palha de uma semeadora-adubadora em diferentes coberturas vegetais e cargas verticais aplicadas. Para a realização do trabalho foi utilizado um dinamômetro (anel ortogonal), projetado, construído e calibrado numa célula de carga padrão. Os experimentos de campo foram conduzidos na Fazenda Experimental Lageado, pertencente a Faculdade de Ciências Agronômicas - Unesp de Botucatu, durante o ano agrícola de 2005-2006. O delineamento experimental utilizado foi em blocos ao acaso e esquema fatorial 3 x 4, com 4 repetições. Os trabalhos foram realizados com 3 diferentes mecanismos de corte de palha, sendo estes: disco liso (DL), disco corrugado (DC) e disco ondulado (DO), utilizando 4 diferentes cargas verticais, sendo estas: 750 (C1), 1500 (C2), 2250 (C3) e 3000 N (C4). Todos os tratamentos foram instalados em 5 diferentes coberturas de palha: milho, sorgo, aveia preta, triticale e nabiça. Os resultados mostraram que quanto maior a quantidade de matéria seca da cobertura vegetal, maior a demanda de forças horizontal e vertical. Quanto maior a carga vertical aplicada, maior a área de solo mobilizado; maiores são as forças horizontal, vertical e lateral; maior a profundidade de penetração dos discos no solo e menores são a força horizontal por profundidade de corte dos discos (profundidade específica) e a força horizontal por área de solo mobilizado. O disco de corte ondulado possibilita os maiores valores de área de solo mobilizado...
|
9 |
Respostas dos grãos de mamona 'AL Guarany 2002' ao tratamento térmico visando ruptura e remoção do tegumento / Response of 'AL Guarany 2002' castor beans to thermal treatment aiming disruption and removal of the seed coatBastos, Adriano Chaves 18 August 2018 (has links)
Orientador: Antônio Carlos de Oliveira Ferraz / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-18T04:19:18Z (GMT). No. of bitstreams: 1
Bastos_AdrianoChaves_M.pdf: 2735079 bytes, checksum: cf97e6f8975f1d257161804823965394 (MD5)
Previous issue date: 2011 / Resumo: Atualmente o Brasil ocupa o terceiro lugar no ranking mundial na produção e extração do óleo de mamona (Ricinus communis L), correspondendo a 13,2%, depois da Índia e da China, primeiro e segundo maiores produtores, respectivamente. Os frutos de mamona, depois de colhidos, são secos e debulhados obtendo os grãos, os quais são armazenados para posteriormente serem encaminhados à extração do óleo. O processo de extração do óleo é realizado pela prensagem dos grãos íntegros: tegumento e endosperma. Este tegumento é pigmentado e abrasivo, desgastando precocemente os equipamentos e demandando processos adicionais de clarificação do óleo. A decorticação dos grãos para a retirada do tegumento, anterior à prensagem, poderia gerar uma economia no processo de extração. O objetivo deste trabalho foi verificar o efeito da temperatura de secagem nas propriedades físico-mecânicas dos grãos de mamona da cultivar 'AL Guarany 2002', após os frutos serem secos e debulhados. Para tal determinação foram efetuados ensaios de compressão entre pratos planos, rígidos e paralelos nos grãos após os tratamentos de secagem, para as direções do comprimento e largura, obtendo-se a força máxima na ruptura do tegumento, energia na ruptura, deformação específica e rigidez. As temperaturas de secagem utilizadas foram de 40, 60, 80 e 100°C. Posteriormente, foram efetuadas avaliações do grau de ruptura do tegumento após os grãos serem submetidos à alta taxa de deformação utilizando-se equipamento projetado e construído para tal finalidade, denominado DIRADEL. Verificou-se nos ensaios de compressão que a secagem dos frutos de mamona a diferentes temperaturas influencia nas propriedades mecânicas dos grãos de mamona. Com o aumento da temperatura de secagem a força e a energia na ruptura do tegumento para a direção do comprimento reduziram-se e, inversamente, estes valores elevaram-se para a direção da largura. Os valores para a direção do comprimento oscilaram entre 55,52 a 63,11 N para a força máxima na ruptura do tegumento, 0,0169 a 0,0202 J para a energia, 4,03 a 4,48% para a deformação específica e 93,29 a 100,62 N.mm-1 para a rigidez. Para a direção da largura os valores oscilaram entre 58,46 a 70,02 N para a força máxima na ruptura do tegumento, 0,0281 a 0,0365 J para a energia, 9,10 a 11,10% para a deformação específica e 62,11 a 70,50 N.mm-1 para a rigidez. Nos ensaios a alta taxa de deformação, a deformação especifica de 14% apresentou a maior porcentagem de grãos com ruptura total do tegumento e liberação do endosperma inteiro, independente da direção e do tratamento de secagem, sendo esta a deformação específica limite. A direção da largura demonstrou porcentagem de grãos com ruptura total do tegumento e endosperma inteiro inferior à posição do comprimento, independente do tratamento de secagem. O desempenho da decorticação dos grãos de mamona pode ser afetado com grãos secos a temperaturas acima de 60°C, pois a retirada excessiva de água do endosperma prejudica sua resistência deixando-o mais frágil. Secagens com temperaturas mais elevadas devem ocorrer com maior cautela se o intuito for a decorticação dos grãos / Abstract: Brazil currently occupies the third position in the world?s ranking production and extraction of castor oil (Ricinus communis L), corresponding to 13.2%, after India and China which are the first and second biggest producers, respectively. The fruits of castor bean, once harvested, are dried and threshed, and when the grains are obtained, they are stored for later transport to oil extraction. This process is done by pressing the intact grain, seed coat and endosperm. The seed coat is pigmented and abrasive, wearing the equipment earlier and requiring additional processes to clarify the oil, afterwards. The decortication of the grain for seed coat removal, prior to pressing, could generate savings in the extraction process. The aim of this study was to assess the effect of drying temperature on physico-mechanical properties of castor beans, cultivar 'AL Guarany 2002', after the fruits were dried and threshed. For such determination, compression tests were made between flat, rigid and parallel plates on the grains, after the drying treatments, to the directions of length and width, obtaining the maximum force at rupture of the seed coat, energy at break, specific deformation and stiffness. The drying temperatures used were 40, 60, 80 and 100 °C. The grains were evaluated based on the degree of disruption of the tegument after the beans are exposed to high strain rate using equipment designed and built for this purpose, called DIRADEL. It was found in compression test that castor fruits dried at different temperatures was influenced by the mechanical properties of castor beans. With the increase of drying temperature, the strength and energy to break the seed coat along the length is reduced and, conversely, these values rose to the width direction. Values for the direction of the length ranged from 55,52 to 63,11 N for the maximum force at rupture of the seed coat, from 0,0169 to 0,0202 J for energy, 4,03 to 4,48% for the specific deformation and from 93,29 to 100,62 N.mm-1 for stiffness. For the width direction, values ranged from 58,46 to 70,02 N for the maximum force at rupture of the seed coat, from 0,0281 to 0,0365 J for energy, 9,10 to 11,10% for the specific deformation, 62,11 to 70,50 N.mm-1 for stiffness. In the experiments at high strain rate, specific deformation of 14%, had the highest percentage of grains with total rupture of the seed coat and endosperm full release, regardless of direction and drying treatment, which is the specific deformation limit. The width direction showed the percentage of grains with total rupture of the seed coat and endosperm lower whole length of the position, regardless of the drying treatment. The performance of the decortication of castor beans can be affected by dry grains at temperatures above 60°C, because the excessive withdrawal of water from the endosperm, affecting their resistance and making it more fragile. Drying at higher temperatures should be done with greater caution when decorticating the grains / Mestrado / Maquinas Agricolas / Mestre em Engenharia Agrícola
|
10 |
Agricultura de precisão em cana-de-açucar : instrumentação de uma colhedora, mapeamento da produtividade e de atributos do solo / Precision agriculture in sugar cane: instrumentation of a harvester, yield and soil attributes mappingCerri, Domingos Guilherme Pellegrino 17 May 2005 (has links)
Orientador: Paulo Sergio Graziano Magalhaes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-05T10:35:05Z (GMT). No. of bitstreams: 1
Cerri_DomingosGuilhermePellegrino_D.pdf: 4121488 bytes, checksum: 9b91abea04eca837abde9f7e2597aa56 (MD5)
Previous issue date: 2005 / Resumo: A presente pesquisa visa instrumentar uma colhedora de cana-de-açúcar para obtenção de mapas de produtividade da cultura e ao mesmo tempo, avaliar e correlacionar os atributos físicos e químicos do solo com os dados de produtividade. Os mapas foram elaborados para uma área de 42 ha da Usina São João Açúcar e Álcool localizada em Araras, SP. O sistema de mapeamento de produtividade de cana-de-açúcar desenvolvido (SIMPROCANA) utiliza células de carga como instrumento de determinação do peso do material colhido e é capaz de mensurar o fluxo de rebolos que passa pela esteira antes de serem lançados ao veículo de transbordo. Estes dados, juntamente com as informações obtidas por um Sistema de Posicionamento Global (GPS) instalado na colhedora, permitem, com o auxilio de um Sistema de Informação Geográfica ¿ SIG, a elaboração de mapa digital que representa a superfície de produção para a área colhida. Este sistema foi testado em laboratório e em campo. O SIMPROCANA representou satisfatoriamente a variabilidade espacial da produtividade da cultura. O peso obtido por esse sistema, comparado com o da carga de cana na balança da usina, apresentou um erro médio de 0,96% com um máximo de 6,4%. O resultado deixa de ser satisfatório quando se compara o peso obtido pelo SIMPROCANA com aquele proveniente do transbordo pesado no campo. O erro médio associado nesse caso é aproximadamente dez vezes maior quando se faz a associação com o peso na balança da usina. Os mapas dos atributos físicos e químicos do solo (granulometria, macro e micronutrientes, acidez, densidade e resistência à penetração) foram confeccionados com base em duas amostragens em anos consecutivos. Na primeira, com o auxílio de um veículo amostrador, foram coletadas 170 amostras na área de 42 ha em uma malha regular de 50 x 50 m. Na segunda, coletou-se 49 amostras em malha de 100 x 100 m definida em base nos alcances máximos obtidos pela análise geoestatística da primeira amostragem. Os resultados da primeira amostragem foram correlacionados com a produtividade da cana-de-açúcar obtida pela pesagem dos transbordos em campo. Esse método alternativo de avaliação permitiu a utilização dos resultados da primeira amostragem, uma vez que a colhedora não estava devidamente instrumentada. Os dados da segunda amostragem foram relacionados ao mapa de produtividade obtido pelo SIMPROCANA. Os resultados das análises físicas e químicas usados para a construção dos modelos dos semivariogramas se ajustaram melhor para a malha de 50 x 50 m do que à de 100 x 100 m. As correlações entre produtividade e atributos do solo apresentaram valores baixos. Os maiores índices ocorreram para as variáveis cobre (0,55), altitude (-0,47%) e teor de argila (0,51%). Apesar dessas baixas correlações, foi possível recomendar uma aplicação variada de insumos baseando-se exclusivamente nas informações dos atributos químicos do solo. Simulações mostraram que os custos de aplicação em taxa variada de fertilizantes fosfatados e potássicos são praticamente 50% menores do que o valor calculado para a taxa fixa. Em relação à calagem não houve variação significativa nos custos de aplicação do calcário pelas duas maneiras / Abstract: The present research aims to instrument a sugarcane harvester in order to obtain the crop yield maps and, at the same time, evaluate and correlate the physical and chemical attributes of the soil using the yield data. In order to obtain these maps, an area measuring 42 ha located at São João Sugar and Alcohol Mill in Araras, São Paulo, Brazil. The yield mapping system of sugarcane crop developed (SIMPROCANA) uses load cells as an instrument to weighing the harvested material and it is capable to measure the flow passing by the matting before being launched to the transport vehicle. These data, together with the information obtained by a Global Positioning System (GPS) installed on the harvester, allow the elaboration of a digital map with the help of a Geographical Information System - GIS that represents the production on the surface for the harvested area. This system was tested under laboratory and field conditions. SIMPROCANA represented satisfactorily the spatial variability of the crop yield. The weight obtained by this system compared with that of sugarcane load in a mill's scale presented an average error of 0.96%, with a maximum of 6.4%. The result is not satisfactory anymore when it compares the weight obtained by using SIMPROCANA with that from the transportation vehicle weighed in the field. The average error associated in this case is around ten fold higher, when the association with the weight obtained in the mill's scale is performed. In relation to the making of map of physical and chemical attributes of soil (granulometry, macro and micronutrients, acidity, density, and resistance to penetration), two samplings were made in consecutive years. In the first
sampling, 170 samples were collected in a 42 ha area in a regular grid of 50 x 50 m, helped by a sampler vehicle. In the second one, 49 samples in a 100 x 100 m grid defined by the maximum reaching obtained by geostatistics analysis performed at the first sampling. The results of the first sampling were correlated with the sugarcane yield obtained by means of weighing the transport vehicle in the field. This alternative method allowed the using of the results from the first sampling once the harvester was not properly instrumented. The data from the second sampling were related to the yield mapping obtained by using SIMPROCANA. The results of the physical and chemical analyses used for the construction of semivariograms models adjusted better at the 50 x 50 m grid when compared to that of 100 x 100 m. the correlations between the yield and the soil attributes presented lower values. The higher indexes occurred for the variable altitudes (- 0.47%), clay rate (0.51%), and copper (0.55). Despite these low correlations, it was possible to recommend a varied rate application of inputs based exclusively on the information obtained from the chemical attributes of the soil. Simulation tests showed that the application costs under a varied rate of phosphated and potash fertilizers are practically half of the value calculated for a fixed rate. In relation to the liming, there was not significative variation in the prices of lime application spread by both methods / Doutorado / Maquinas Agricolas / Doutor em Maquinas Agricolas
|
Page generated in 0.0658 seconds