A portable dual-camera video system was used to evaluate the potential for using total projected green cover as an indirect measure of weed infestations in a wheat crop during early growth stages. The video system would have applications in mapping weed infestations to assist precision farming operations. <p>The two cameras provided a real-time composite image of reflected light measured in red (640 nm), and near-infrared (860 nm) wavelengths. A simple ratio of reflected light intensity in each wavelength was used to isolate the growing plants from the background. Software was developed to automatically adjust for varying ambient light conditions and calculate the percentage of the image occupied by growing plants. Total green cover was measured at randomly selected sites prior to direct seeding wheat and at four growth stages following wheat emergence. The portion of green cover observed was compared to crop and weed dry matter at each location. Weed infestations at each location were estimated by measuring the total green cover and subtracting the projected green cover due to the crop alone. A minimum weed dry matter of 20 g/m2 and 30 g/m2 could be detected by the video system at the 3-leaf and 5-leaf growth stages, respectively. Weed dry matter less than 20 g/m2 could not be detected reliably due to the variability of the wheat crop. Detection of weeds within the crop beyond the 5-leaf stage using this method was difficult due to crop canopy closure.

A portable dual-camera video system was used to evaluate the potential for using total projected green cover as an indirect measure of weed infestations in a wheat crop during early growth stages. The video system would have applications in mapping weed infestations to assist precision farming operations. <p>The two cameras provided a real-time composite image of reflected light measured in red (640 nm), and near-infrared (860 nm) wavelengths. A simple ratio of reflected light intensity in each wavelength was used to isolate the growing plants from the background. Software was developed to automatically adjust for varying ambient light conditions and calculate the percentage of the image occupied by growing plants. Total green cover was measured at randomly selected sites prior to direct seeding wheat and at four growth stages following wheat emergence. The portion of green cover observed was compared to crop and weed dry matter at each location. Weed infestations at each location were estimated by measuring the total green cover and subtracting the projected green cover due to the crop alone. A minimum weed dry matter of 20 g/m2 and 30 g/m2 could be detected by the video system at the 3-leaf and 5-leaf growth stages, respectively. Weed dry matter less than 20 g/m2 could not be detected reliably due to the variability of the wheat crop. Detection of weeds within the crop beyond the 5-leaf stage using this method was difficult due to crop canopy closure.

In the recent past precision farming has become increasingly popular amongfarmers. However, little has been done to study the business aspect of precision farming,with most research focusing on the production side. This purpose of this thesis is tostudy the feasibility of successfully opening and operating a precision farming firm inKentucky. To determine the feasibility of such a venture a computer model was createdand a producer survey was designed and distributed to farmers in Western and CentralKentucky.The purpose of the computer model was to determine the factors that wouldinfluence the successful operation of a precision farming firm including number of acresserviced per year, pricing of services, the cost of capital to borrow money, and manyother factors. A break-even analysis was performed to determine what kind of annualincreases in business would be required, what price range services should be in, and atwhat interest rate money could be borrowed and a simulated precision farming firm couldstill operate successfully.The producer survey was mailed to 336 farmers in Western and Central Kentuckybecause of their geographical locations and the type of crops that are grown there. Thesurvey response rate was 20 percent and of the 66 surveys that were returned 59 wereappropriate and useful for research. After compiling the results of the surveys,regressions were run to determine any correlation between dependent and independentvariables that affect the adoption rate of precision farming techniques. The results foundthat a negative correlation exists between age adoption rates of precision farming and thata positive correlation exists between farm size and adoption rates of precision farming.After conducting the research, it is believed that given the right economicconditions and management a precision farming firm is very capable of thriving inKentucky. However, the workforce must be very motivated and capable of constantlyrecruiting new clients to adopt precision farming.

Orientador: Nelson Luis Cappelli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-08T08:17:38Z (GMT). No. of bitstreams: 1 Russo_Edison_M.pdf: 3049546 bytes, checksum: db5a147e4c50fbd23b80474bbc4e36c9 (MD5) Previous issue date: 2005 / Resumo: A agricultura moderna busca novas tecnologias para a aplicação de insumos com maior precisão e com a finalidade de; aumentar a produtividade, minimizar os impactos ambientais, reduzir custos de produção, melhorar a qualidade dos produtos, etc. Neste sentido, tem sido necessário o desenvolvimento de máquinas mais adequadas, com capacidade de operação e precisão elevadas. A tendência atual no desenvolvimento de tais máquinas aponta no sentido da automação e na introdução de sistemas eletrônicos embarcados. O objetivo deste trabalho foi o desenvolvimento de um Módulo de Interface (MDI) para ser utilizado em um Sistema de Formulação e Aplicação Localizada de Nutrientes Líquidos a Taxas Variáveis, proposto pelo Laboratório de Instrumentação e Controle - LIC da Faculdade de Engenharia Agrícola da Universidade Estadual de Campinas. A função do MDI é receber as informações provenientes do módulo de controle do sistema de aplicação, efetuar as leituras dos sensores de campo, processar os dados e comandar os periféricos envolvidos na aplicação, tais como; bombas, eletro-válvulas e válvulas proporcionais para controle de fluxo. O MDI pode acionar até três grupos de válvulas, sendo que cada grupo pode operar com até quinze válvulas proporcionais para o controle de fluxo de nutrientes. Para garantir a precisão da aplicação foram utilizadas válvulas proporcionais, desenvolvidas pelo LIC, acionada por servo-motores comandados por sinais modulados por largura de pulso (Pulse Width Modulation -PWM) e com características de ciclo ativo inferiores a dez por cento do pulso, o que demanda alta velocidade de processamento. Devido às limitações de velocidade de processamento dos micro-controladores e do custo do equipamento, desenvolveu-se hardware e software visando a otimização das funções executadas pelo MDI de modo a possibilitar a operação com apenas um micro-controlador. Os resultados das avaliações realizadas demonstraram que o MDI apresentou desempenho até mesmo superior aos requeridos pelo sistema de aplicação localizada de insumos líquidos / Abstract: Modern agriculture searches for new technologies for the application of nutrients with greater precision in order to increase productivity, minimize the impact in the environment, reduce production costs, improve the quality of the products etc. In order to achieve that, it has been necessary to develop more adequate machines, with higher operation capacity and precision. Nowadays, the development of such machines tends towards automation and the introduction of embed electronic systems. The aim of this work was the development of an Interface Module (MDI) to be used in a system for application of liquid products, proposed by the Control and Instrumentation Laboratory (LIC) from the Faculty of Agricultural Engineering at Unicamp. The function of the MDI is to receive the information proceeding from the Control Module, carry out the readings of the field sensors, process all this data and command the peripherals involved in the application, like: pumps, electro-valves for flux of nutrients control. The MDI can operate up to three groups of valves, which means that each group cam operate up to fifteen proportional valves, to control the flux of the nutrients. In order to assure the precision of the application, proportional valves, which have been developed by the LIC, activated by servo-motors and controlled by modulated signals through pulse width (PWM), have been used with characteristics of active cycles inferior to ten per cent of the pulse, what demands high speed of processing. Due to the limitations of the speeding process of micro-controllers and the cost of equipment, hardware and software have been developed, aiming to optimize the functions performed by the MDI to enable the operation with only one micro-controller. The results of the valuation have shown that the MDI has surpassed the performance required by the application system of liquid nutrients / Mestrado / Maquinas Agricolas / Mestre em Engenharia Agrícola