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Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este artigo objetiva a análise histórica do segmento de máquinas agrícolas (tratores e colheitadeiras) no Brasil, refletindo os entraves geopolíticos para a indústria genuinamente nacional e sua evolução. Trata-se de pesquisa apoiada em referencial teórico objetivando a compreensão dos contextos históricos, a concepção de desenvolvimento nacional e a gênese e desenvolvimento do segmento industrial. Como ilustração e verificação das contradições dos contextos históricos houve a análise de dados oficiais e corporativos, contraditados com as potencialidades brasileiras, as experiências e os impedimentos para a plena realização nacional do segmento, discutidas sob as premissas de autores da história econômica do Brasil. Conclui-se que os entraves históricos para a industrialização brasileira foram influenciados por oligarquias nacionais em aliança com o capital estrangeiro. Com a Revolução de 1930 mudaram-se os paradigmas, foi erguida a indústria de base e instauradas políticas nacionais-desenvolvimentistas que potencializaram o crescimento econômico, suscitando a gênese da indústria brasileira de máquinas agrícolas. Porém, anos mais tarde, foram revistos pressupostos, abrindo-se o mercado para a instalação de empresas estrangeiras no país. A indústria nacional não resistiu à força estrangeira e à desproteção estatal a partir da segunda metade da década de 1970, desconstituindo-se, desnacionalizando-se, formando o atual oligopólio estrangeiro.

Copyright of Revista de Economia e Sociologia Rural is the property of Sociedade Brasileira de Economia e Sociologia Rural and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A agricultura familiar é responsável por uma parcela importante da produção agrícola do país, entretanto se depara com deficiências principalmente no que se refere às máquinas agrícolas compatíveis com suas necessidades. Neste contexto, a abordagem do presente estudo foi caracterizar as demandas dos produtores familiares da região sul do Rio Grande do Sul, em relação a mecanização utilizada na produção de hortaliças e tabaco. As informações foram coletadas junto aos produtores por meio de entrevistas. Utilizou-se um questionário semiestruturado, o qual, permitiu a combinação de perguntas abertas e fechadas. Constatou-se que os produtores familiares que produzem hortaliças e tabaco na região estudada, necessitam de um sistema mecanizado capaz de formar canteiros e depositar fertilizantes em uma única operação. Além disso o equipamento deve possuir baixo custo e de fácil abastecimento. Também foi constatado que os tratores de quatro rodas utilizados pelos produtores variam entre 36,77 e 62,52 kW de potência no motor.

Sugarcane culture is one of Brazil's main commodities, positioning the country as the world's largest producer of sugarcane. The competitive dynamics of the sector is governed, predominantly, by cost reduction, so technological advances increase management challenges, especially in the analysis of the economic viability of the projects. Therefore, from the perspective of portfolio management, the evaluation of the economic viability of projects becomes a great ally for selecting and prioritizing investments. At this point, it should be noted that this work aimed to develop an economic viability study, in a project to renovate equipment for sugarcane cultural treatment operations, aiming at comparative assessment within a company's project portfolio. To this end, a case study was carried out in a group in the sugar-energy sector, which presents its sugarcane processing units in the northwest of the State of São Paulo. The results provide a differentiated way to construct the discounted cash flow, in order to allow the extraction of viability indicators. It was found that the renewal of the equipment is economically viable, since it presented an NPV of R$ 1,040,383, IL of 1.24 and an IRR of 19.72%, and even considering the Monte Carlo Simulation with 10,000 possibilities, the viability was identified in 100% of the cases. In this way, this study brings new insights to the portfolio investment selection process and demonstrates the need for ongoing investment policies in new technologies for the sugar-energy sector. [ABSTRACT FROM AUTHOR]

Copyright of Tecno-Lógica is the property of Tecno-Logica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O presente artigo apresenta um mapeamento cognitivo causal elaborado a partir de pesquisas realizadas por especialistas a respeito dos temas ergonomia e segurança em tratores agrícolas. Utilizou-se o mapeamento para representar as informações disponibilizadas em normas técnicas e regulamentadoras nacionais, bem como, em trabalhos científicos divulgados no Portal de Periódicos CAPES/MEC. Os procedimentos adotados na construção dos mapas foram a pesquisa documental e bibliográfica. Além disso, fez-se entrevistas com especialistas em máquinas agrícolas a fim de considerar suas experiências a partir de padrões pessoais de conhecimento. Objetivou-se, através da elaboração do mapeamento, a visualização das relações de causa e efeito dos temas aplicados aos tratores agrícolas. Com a análise do mapeamento cognitivo identificaram-se itens e índices adequados para a avaliação de níveis ou graus de eficácia funcional e satisfação dos diversos atores quanto à ergonomia e à segurança dessas máquinas, de forma a determinar ações potenciais para apoiar a tomada de decisão no momento em que o agricultor venha a adquiri-las.

The inspection of agricultural sprayers is a vital tool for the increment of quality of spray technology for phytosanitary products. The objective of this work was to evaluate the performance conditions of self-propelled sprayers onfarm, using the periodical inspection methodology for sprays and analyzing the climatic conditions during the spraying. The evaluations were carried on farms visited randomly. A questionnaire was filled out by the operator or farmers and the inspection itself of the sprayers. The items evaluated were the condition and location of hoses, presence of leaks, monitor performance, spacing between nozzles, spray nozzles, in-line filter, primary filter, the performance of anti-dripping gauges, and limiting environmental conditions. Most interviewed operators and farmers did not know the methodology for inspecting agricultural sprayers, demonstrating the need to create specific training programs in the region. Self-propelled sprayers have a few technical problems when they were new, however, spraying beyond the ideal weather conditions can reduce the spraying quality. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this research was to forecast the Brazilian national production of agricultural and road machinery in the short term by BOX & JENKINS methodology and determine the persistence effect. Data were obtained at National Association of Automotive Vehicle Manufacturers (ANFAVEA) from January 1960 to October 2019, totaling 718 monthly observations. The Autoregressive Integrated Moving Average (ARIMA) and Autoregressive Conditional Heteroscedasticity (ARCH) methodology were used. The ARIMA (2,1,1)-ARCH (2) model was fitted and persistence of 0.60 was determined, showing that the instability in the series will be for a long period of time. [ABSTRACT FROM AUTHOR]

The investigation was carried out in the municipality of Zinacantepec, State of Mexico, through an exploratory, descriptive, nonexperimental study, The main objective is to know the current situation of the level of mechanization of the tractors and agricultural machines that agricultural producers have, to identify technical indexes, in order to optimize them for the sake of efficient productivity. The average age of tractors is 7.73 years old, its concentration is located at 77.38% in areas smaller than 10 ha; which indicates underutilization, joined with an inadequate maintenance program; which leads to premature tractor danger. [ABSTRACT FROM AUTHOR]

Copyright of Tecno-Lógica is the property of Tecno-Logica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tecno-Lógica is the property of Tecno-Logica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se lleva a cabo una investigación en el municipio de Zinacantepec, Estado de México, por medio de un estudio exploratorio, descriptivo no experimental, con el objetivo de conocer la situación actual del nivel de mecanización de los tractores y las máquinas agrícolas que poseen los productores agropecuarios y así identificar índices técnicos para optimizarlos en aras de una productividad eficiente. El promedio de edad que tienen los tractores es de 7.73 años, su concentración se localiza en 77.38 % en superficies menores a 10 ha, lo cual indica una subutilización, aunado a un programa de mantenimiento no adecuado que conlleva al deterioro prematuro del tractor.

O tipo de funcionamento do mecanismo dosador das semeadoras e a velocidade de operação, são determinantes na produtividade da cultura. O presente trabalho teve como objetivo estudar a influência da velocidade de deslocamento na semeadura do milho, com diferentes modelos de semeadoras e mecanismos dosadores de semente. Sendo os mecanismos dosadores: disco alveolado perfurado horizontal com acionamento mecânico, pneumático e pneumático com kit auxiliar eSet. O delineamento experimental foi realizado em blocos ao acaso, com 04 repetições sendo um fatorial com três diferentes velocidades de deslocamento 5, 7 e 9 km h-1 e dois tipos de mecanismo dosador de sementes sendo um com kit auxiliar. As variáveis mensuradas foram: a distribuição longitudinal espaçamentos múltiplos, falhos, aceitáveis, peso de mil sementes, número de espigas, coeficiente de variação, precisão e a produtividade de milho. O incremento na velocidade de deslocamento das semeadoras interferiu, nas variáveis: falhos, múltiplos, aceitáveis, número de plantas e número de plantas com espiga. A semeadora John Deere com mecanismo dosador pneumático com o kit eSet na velocidade de 5 km h-1 ficou dentro do nível tolerado de precisão dos espaçamentos entre plantas. O aumento de velocidade nas semeadoras e os respectivos mecanismos dosadores não tiveram influência na produtividade do milho.

ABSTRACT: The great difficulty for family farmers who produce food organically is the control of weeds without using chemical products. One possibility for the management is the use of heat in the sense of coagulating the protoplasm in leaves and stem cells. The present research aimed toconceptual design a mechanized system for weeds control through the use of heat focusing on familiar farmers who produce food organically. In this study, we used a product development methodology which can be divided into different stages that are composed of several tasks. As a result of the use of such methodology, six concepts of heat transfer machines were developed. After the application of selection tools, two concepts were chosen for the optimization process, and then the one considered ideal to meet the needs of farmers was selected.

The objective of this work is to determine the physical-mechanical properties of banana bunches as an object of their transportation in aerial cable and the parameters required for the design of a transport system of banana bunches in mountainous areas of Trujillo State, Venezuela. A descriptive analysis of all the samples was carried out for the properties studied, obtaining the arithmetic mean and the dispersion measurements (standard deviation and coefficient of variation), as well as a variance analysis, determining the p-value and an analysis of simple and multiple regression. The results obtained show that the arithmetic mean obtained for the diameter of the rachis was 5,41 cm, with a standard deviation of ± 0,77 cm; the length of the clusters 63,96 cm, with a standard deviation of ± 14,92 cm and the diameter of the bunches amounted to 33,67 cm, with a standard deviation of ± 2,69 cm. Furthermore, the mass of the bunches obtained amounted to 16,58 kg, with a standard deviation of ± 4,91 kg, the Xc and Yc coordinates, obtained from the center of mass of the clusters reached 16,73 and 28,84 cm, with a standard deviation of ± 1,37 and 3,78 cm, respectively. In addition, the moment of inertia amounted to 0,13 kg m2 with a standard deviation of ± 0,11 kg m². The best adjusted model of the relationship between the moment of inertia and the mass of banana clusters was the Box-Cox Method with an R² of 86, 65%. Regarding the relationship with the bunch diameter, the model that was best adjusted was the Polynomial with an R² of 88, 7%. [ABSTRACT FROM AUTHOR]

Copyright of Engenharia na Agricultura is the property of Engenharia na Agricultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engenharia na Agricultura is the property of Engenharia na Agricultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Engenharia na Agricultura is the property of Engenharia na Agricultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Agricultural tractors have been reported to exert negative effects on operator health. It is well known that when a farm machine is designed it must consider the human factors, to raise the safety levels and work quality. The aim of the present study was to estimate the degree of vibration transmissibility from the agricultural equipment used for the periodic soil preparation process and determine the exposure of the whole body of the operator to the vibration, incident to the agricultural tractor during the operation. A 4x2 TDA tractor was employed, coupled to the periodic soil preparation equipment. Five sets were used (tractor- disk plough, tractor-moldboard plow, tractor-offset disc harrow, tractor-rotary hoe, and tractor-scarifier) and the tractor without the equipment being coupled, at two tractor speeds of displacement (3.5 km.h-1 and 6.1 km.h-1). An index (IAVEA) was developed to assess whether the amplification or attenuation of the vibrations takes place on each orthogonal axis. The data were processed using the Noise Studio® software 6.95. Statistical evaluation was performed using the ASSISTAT version 7.7 beta program. After normality, the data were submitted to the analysis of variance by the F test; when significance was reported, the means were compared using the Tukey test, at 5% significance. The disk plow was the equipment that showed the greatest intensification of the vibrations in all the parameters estimated. All the sets assessed revealed statistically equal or higher values in terms of the tractor without the attached equipment. The IAVEA% was an index that enabled the quantification of the amplification or attenuation caused by the use of the agricultural equipment. [ABSTRACT FROM AUTHOR]

Copyright of Engenharia na Agricultura is the property of Engenharia na Agricultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The great difficulty for family farmers who produce food organically is the control of weeds without using chemical products. One possibility for the management is the use of heat in the sense of coagulating the protoplasm in leaves and stem cells. The present research aimed toconceptual design a mechanized system for weeds control through the use of heat focusing on familiar farmers who produce food organically. In this study, we used a product development methodology which can be divided into different stages that are composed of several tasks. As a result of the use of such methodology, six concepts of heat transfer machines were developed. After the application of selection tools, two concepts were chosen for the optimization process, and then the one considered ideal to meet the needs of farmers was selected. [ABSTRACT FROM AUTHOR]

The production of industrial tomato in Brazil has been growing in the last years and the form of harvest adopted has been mechanized. The diagnosis of tomato fruit losses is fundamental to the harvesting process. The industrial process was destroyed and the statistical process control. The experiment was carried out in a field of 45 ha in an industrial tomato crop irrigated by central pivot in the municipality of Corumbá de Goiás, GO, Brazil. A sampling grid of 60 x 60 m (120 sample points) and 100 x 50 (84 sample points), respectively, were used as georeferenced samples to quantify weight loss and poisoning. As the main losses, in the mechanized harvest, the fruit of industrial tomato do not occur with mature fruit. A N901 cultivar had a lower quality relation than a HMX7885. The mechanical tomato harvesting process is influenced by the random power medium during a larger part of the operation. However, throughout the year, the tasks are not random, they are involved with the operation and the maintenance and maintenance of the process is necessary. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Agricolas is the property of University of Narino, Faculty of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cientifica is the property of Fundacao de Apoio a Pesquisa e Extensao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A produtividade do setor agrícola brasileiro e a oferta do produto final ao mercado consumidor estão diretamente relacionadas com a mecanização em todas as etapas do processo produtivo. No entanto, poucos agricultores familiares possuem acesso à mecanização agrícola devido alto custo do investimento inicial. O presente trabalho descreve as principais dificuldades para a implementação de máquinas agrícolas na agricultura familiar e os principais problemas da mecanização. Contudo, pôde-se observar que a mecanização é pouco empregada pelos agricultores familiares, no entanto, as patrulhas agrícolas possibilitam o emprego de máquinas pelos pequenos agricultores.

Citrus plants are the most important fruit species in the world, with emphasis to oranges, mandarins and lemons. In Rio Grande do Sul, Brazil, most fruit production is found on small properties under organic cultivation. Soil compaction is one of the factors limiting production and due to the fixed row placement of this crop, compaction can arise in various manners in the interrows of the orchard. The aim of this study was to evaluate soil physical properties and water infiltration capacity in response to interrow management in an orchard of mandarin (Citrus deliciosa Tenore 'Montenegrina') under organic cultivation. Interrow management was performed through harrowing, logs in em "V", mowing, and cutting/knocking down plants with a knife roller. Soil physical properties were evaluated in the wheel tracks of the tractor (WT), between the wheel tracks (BWT), and in the area under the line projection of the canopy (CLP), with undisturbed soil samples collected in the 0.00-0.15, 0.15-0.30, 0.30-0.45, and 0.45-0.60 m layers, with four replicates. The soil water infiltration test was performed using the concentric cylinder method, with a maximum time of 90 min for each test. In general, soil analysis showed a variation in the physical-hydraulic properties of the Argissolo Vermelho-Amarelo distrófico arênico (sandy loam Typic Paleudalf) in the three sampling sites in all layers, regardless of the management procedure in the interrows. Machinery traffic leads to heterogeneity in the soil physical-hydraulic properties in the interrows of the orchard. Soil porosity and bulk density are affected especially in the wheel tracks of the tractor (WT), which causes a reduction in the constant rate of infiltration and in the accumulated infiltration of water in this sampling site. The use of the disk harrow and mower leads to greater harmful effects on the soil, which can interfere with mandarin production.

O milho e o feijão são semeados em praticamente todas as pequenas unidades familiares de produção, normalmente, em sistema convencional de cultivo. Há interesse no sistema de semeadura direta, porém não estão disponíveis semeadoras adequadas às suas necessidades. As semeadoras manuais, utilizadas por esses agricultores, inclusive para semeadura direta, possuem restrições de capacidade e de desempenho operacional, além de problemas ergonômicos. É necessário o desenvolvimento de máquinas desse porte, que garantam maior qualidade na operação de semeadura dessas culturas. O objetivo do presente trabalho foi estabelecer a estrutura funcional de uma semeadora puncionadora de tração humana para semeadura direta de milho e feijão. Foi aplicada uma metodologia sistemática, contemplando análise de especificações, identificação de restrições e estabelecimento das estruturas funcionais em diagrama de blocos. Foi eleita a estrutura funcional de empurrar com um dosador e múltiplos abridores de solo.

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to establish client and design requirements of a human-powered planter. A total of 13 client requirements and 13 design requirements were established for prioritizing planter performance, thus providing benefits to users. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Applied Technology for Agricultural Science / Revista Brasileira de Tecnologia Aplicada nas Ciências Agrárias is the property of Brazilian Journal of Applied Technology for Agricultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O presente trabalho contribui com o estudo da gênese e da evolução histórica da indústria de máquinas e implementos agrícolas, destacando o papel de algumas empresas e como suas estratégias moldaram a estrutura produtiva e de mercado atuais, um "oligopólio diferenciado-concentrado mundial". Do ponto de vista metodológico, este é um texto qualitativo-quantitativo, exploratório e descritivo. A pesquisa bibliográfica mostrou que existiam poucos trabalhos sobre a evolução da estrutura de mercado e das empresas atuantes neste segmento, o que gerou a necessidade de um levantamento exploratório de dados e uma ampla revisão de literatura. O texto mostra a importância do progresso técnico e dos ganhos de escala no processo competitivo deste setor. O trabalho conclui que o setor tem as características de um oligopólio diferenciado-concentrado, sendo a inovação e a diferenciação de produtos através da fidelização dos clientes à marca de dois importantes instrumentos competitivos, assim como as economias de escala e escopo. Outra característica fundamental é o caráter global desta concorrência, com poucas empresas com atuação mundial e muitas com atuação regional ou local.

O uso de hastes sulcadoras nas semeadoras-adubadoras de plantio direto tem-se generalizado, principalmente, em áreas de solos argilosos, como alternativa para romper a camada superficial mais compactada. Entretanto, em determinadas condições, a eficiência da haste sulcadora não se mantém, por causa das características relacionadas com o solo, com a semeadura e, até mesmo, com o próprio sistema de preparo. O objetivo deste trabalho foi avaliar o desempenho de hastes sulcadoras, quanto à demanda de energia, em cinco modelos de hastes sulcadoras para semeadora-adubadora no sistema plantio direto. O experimento foi conduzido no campo experimental da empresa Jumil, na cidade de Batatais - SP. Foi utilizada uma semeadora-adubadora da marca Jumil, modelo Guerra JM 7090 EX, com cinco unidades de semeadura. A semeadura do milho foi realizada sobre palhada de braquiária (Urochloa) e foram avaliadas a força e potência na barra de tração, a velocidade de deslocamento, a capacidade de campo operacional e a produtividade da cultura. A produtividade da cultura do milho, a capacidade de campo operacional e a velocidade de deslocamento não apresentaram diferenças para as cinco hastes estudadas e a haste 4, com formato parabólico, apresentou a menor demanda de força de tração e de potência, na barra.

A produção de frutos de açaí é proveniente, em sua maioria, do extrativismo, mas existe uma forte tendência de implementação de cultivos comerciais. A colheita dos frutos é realizada exclusivamente por escaladores, que se arriscam a sofrer acidentes, além de não terem grande eficiência na colheita. O objetivo deste trabalho foi realizar os desenhos conceituais de colhedoras autopropelidas de açaís em ambientes de matas de terra firme, matas de várzea e cultivos comerciais. Para tal foi utilizada a metodologia de projeto de matriz morfológica. Como resultados foram obtidos os desenhos conceituais destas novas colhedoras: Colhedora de açaí para matas de várzea nativas em estação de cheia; Colhedora de açaí para matas de terra firme nativas e matas de várzea em estação de seca; Colhedora de açaí para cultivos comerciais.Production of the açai fruit is mainly accomplished through manual collection; but there is a strong trend towards the implementation of commercial crops. Fruit harvesting is carried out exclusively by climbers who risk injury to themselves, besides not being very efficient at harvesting. The aim of this study was to produce design concepts for self-propelled açai harvesters for dry-land forest environments, floodplain forest environments and commercial crops. To this end we used the design methodology of a morphological matrix. The results obtained were the design concepts for the following new harvesters: an açai harvester for native floodplain forests in the wet season; a harvester for both dry-land and native floodplain forests in the dry season; a harvester for commercial crops.

The objective of this study was to evaluate the quantitative losses occurred in the mechanical harvesting of the corn grown in conventional and reduced gaps. The experimental design was randomized blocks with three replications and treatments distributed in a factorial (2 x 3 x 3), and two spacings (0.45 m and 0.90 m), three speeds of the combine (1.8 km.h-1 3.5 km.h-1 and 4.1 km.h-1) and three openings of the concave (25 mm, 30 mm and 35 mm). For treatments where the spacing was 0.45 m, the harvester worked with a power of two lines dividing line between the platform crop while in treatments where the spacing was 0.90 m, the harvester worked with a power dividing line between a line of platform. The plant population was the same for the two spacings used in the experiment. The natural losses were higher in the conventional spacing, but the header losses of harvest had the lowest use this space at a speed of 3.5 km.h-1. As maiores perdas ocorreram nos mecanismos internos da colhedora ocorreu quando se utiliza a abertura côncava de 30 mm a uma velocidade de 3,5 km.h-1. Total losses accounted for 8.2% and 7.3% of the average productivity in the gaps of 0.45 m 0.9 m respectivelyObjetivou-se com este trabalho, avaliar as perdas quantitativas ocorridas na colheita mecanizada do milho cultivado em espaçamentos reduzido e convencional. O delineamento experimental foi o de blocos casualizados com três repetições em esquema fatorial (2 x 3 x 3), sendo dois espaçamentos ( 0,45m e 0,90m): três velocidades da colhedora (1,8 km.h-1 3,5 km.h-1 e 4,1 km.h-1) e três aberturas do côncavo (25 mm, 30 mm e 35 mm). Para os tratamentos onde o espaçamento entre linhas foi de 0,45 m, a colhedora trabalhou com uma alimentação de duas linhas entre os divisores de linha da plataforma de colheita enquanto nos tratamentos onde o espaçamento foi de 0,90 m, a colhedora trabalhou com uma alimentação de uma linha entre os divisores de linha da plataforma. A população de plantas foi a mesma para os dois espaçamentos utilizados no experimento. As perdas naturais foram maiores nos tratamentos com espaçamento convencional, porém as perdas na plataforma de colheita apresentaram os menores valores utilizando esse espaçamento na velocidade de 3,5 km.h-1. As maiores perdas ocorridas nos mecanismos internos da colhedora ocorreram quando se utilizou abertura do côncavo de 30 mm a uma velocidade de 3,5 km.h-1. As perdas totais representaram 8,2% e 7,3% da produtividade media nos espaçamentos de 0,45 m e 0,9 m respectivamente

O alto investimento em operações agroflorestais mecanizadas implica a definição segura de qual será a máquina mais preconizada para a otimização da operação, vinculada aos menores custos envolvidos. Este estudo teve como objetivo avaliar o desempenho operacional e econômico da operação silvicultural de irrigação pós-plantio de eucalipto a campo. A análise técnica englobou um estudo de tempos e movimentos e, a análise econômica, as variáveis do custo operacional, custo de produção e rendimento energético. Os resultados obtidos evidenciaram que, para áreas de reflorestamento de eucalipto em primeira e terceira rotação, não há uma diferença da capacidade de campo efetiva para a operação de irrigação pós-plantio. Em decorrência do dispêndio com tempos improdutivos, houve uma redução significativa na capacidade de campo operacional e, consequentemente, uma elevação no custo de produção.

When using appropriate inflation pressures and load capacity (ballast), it may obtain a higher yield and prolongation of the life of the tire, besides it may minimize the problems of loss of traction, increased slippage and fuel consumption. This study aimed to evaluate the fuel consumption of a tractor operating with new and worn tires in three conditions of ballasting and three inflation pressures, when driving on compacted soil with vegetation cover. The experiment was conducted at the experimental unit from the Department of Animal Science, Federal University of Lavras, state of Minas Gerais, Brazil, in an agricultural soil compacted by cattle trampling and with vegetation cover. It was used a tractor 4x2 with front wheel assist, of a 65.62 kW engine power. The tires were of R1 type, diagonal (front: 12.4 to 24; and rear: 18.4 to 30), the average height of the clutches of the new tires were 0.3 and 0.35 m for front and rear tires, respectively, and for the worn tires were 0.018 and 0.0045 m, for the front and the rear tires, respectively. The results showed advantages for the tractor equipped with new tires.Ao se utilizar pressão de inflação e a capacidade de carga (lastro) adequadas, pode-se obter um rendimento maior e um prolongamento da vida útil do pneu; além disso, minimizam-se os problemas de perda de tração, aumento de patinhagem e consumo de combustível. O presente trabalho teve como objetivo avaliar o consumo de combustível de um trator agrícola operando com pneus novos e desgastados, em três condições de lastragem e três pressões de inflação, ao trafegar sobre solo compactado com cobertura vegetal. O experimento foi realizado na unidade experimental do Departamento de Zootecnia da Universidade Federal de Lavras, Lavras-MG, em um solo compactado pelo pisoteio de bovinos e com cobertura vegetal. Utilizou-se um trator 4x2 TDA, com potência de 65,62 kW no motor. Os pneus foram do tipo R1, diagonal (dianteiros: 12,4-24; traseiros: 18,4-30), sendo que a altura média das garras dos pneus novos foi de 0,3 e 0, 35 m para os pneus dianteiros e traseiros, respectivamente, e nos pneus desgastados, 0,018 e 0,0045 m para os pneus dianteiros e traseiros, simultaneamente. Os resultados evidenciaram vantagens para o trator quando equipado com pneus novos.

As organizações líderes dos mais diferentes setores têm como característica medir o próprio desempenho de modo sistêmico, porém nas empresas agrícolas ainda não é comum o emprego desse conceito, incluindo o setor de mecanização. A mecanização tem um forte impacto na composição dos custos de produção, e conhecer o seu desempenho é primordial para o sucesso de empresa agrícola. A importância que as medidas de desempenho têm no auxílio à gestão e o que a mecanização representa para os custos de produção justificaram o desenvolvimento deste trabalho, que tem como objetivo propor um sistema de medição de desempenho integrado para dar suporte à gestão da mecanização agrícola. A metodologia foi dividida em duas etapas: adaptação de um modelo conceitual sistêmico, com base no Balanced Scorecard - BSC; aplicação do modelo a um estudo de caso na agroindústria canavieira. A adaptação e a aplicação do modelo conceitual permitiu obter indicadores de desempenho de modo sistêmico e associados a: custo e prazo (tradicionalmente utilizados); controle e melhoria na qualidade de operações e processos de apoio; preservação ambiental; segurança, saúde, satisfação, motivação e capacitação de colaboradores; desenvolvimento de sistemas de informação. Conclui-se que o modelo auxiliou na elaboração do sistema de medição de desempenho para a gestão de sistemas mecanizados e que os indicadores permitem uma visão integrada da empresa e associada aos objetivos estratégicos.The leaders' organizations of several different sectors have as characteristic to measure their own performance in a systematic way. However, this concept is still unusual in agricultural enterprises, including the mechanization sector. Mechanization has an important role on the production costs and to know its performance is a key factor for the agricultural enterprise success. This work was generated by the importance that measurement of performance has for the management and the mechanization impact on the production costs. Its aim is to propose an integrated performance measurement system to give support to agricultural management. The methodology was divided in two steps: adjustment of a conceptual model based on Balanced Score Card BSC; application of the model in a study case at sugar cane mill. The adjustment and the application of the conceptual model allowed to obtain the performance index in a systematic way, that are associated to: costs and deadline (traditionally used); control and improvement on the quality of operations and support process; environmental preservation; safety; health; employees satisfaction; development of information systems. The adjusted model helped the development of the performance measurement system for the mechanized management systems and the index allows an integrated view of the enterprise, related to its strategic objectives.

A ensilagem de plantas é prática comum no Brasil, onde se busca o armazenamento de alimentos com altos teores de energia, provenientes de plantas forrageiras para utilização em períodos de escassez. A obtenção de silagem de boa qualidade começa com a uniformidade de processamento das culturas pelas máquinas ensiladoras. Assim, este trabalho buscou avaliar a uniformidade de tamanho do picado de milho e sorgo forrageiro processado por colhedora de forragem, avaliando a metodologia para a determinação granulométrica das partículas e definindo a melhor regulagem para o uso da colhedora. Foram avaliadas duas regulagens da colhedora para tamanhos de corte entre 4 e 22 mm, sobre as culturas de milho e sorgo forrageiro. Foi determinado que a regulagem de corte para 4 mm demonstrou maior uniformidade de picado em relação à regulagem de 22 mm, valores de concentração de partículas de 63,2% e 44,6% para as regulagens, respectivamente, na faixa recomendada. Assim, a regulagem para 4 mm deve ser a recomendada para o processamento de culturas de sorgo forrageiro e milho, com uso da colhedora testada. A metodologia utilizada para a determinação da uniformidade de picado permitiu avaliação com rapidez, eficiência e simplicidade.The process of plants ensilage is a common practice in Brazil which provides the housing of animal feeds with high level of energy through plants to use in periods of shortage. To obtain silage with good quality it is needed a uniformity during the harvesting of plants by forage harvesters. Therefore, this research aimed to evaluate the uniformity of pricked corn and sorghum harvested by forage harvester, by assessing the methodology proposed to determine the sizes of the plant particles and to define the best adjustment for using the harvester. It was evaluated two adjustments for size cutting, 4 and 22 mm, on corn and sorghum harvesting. The adjustment of 4 mm showed a larger uniformity of pricked than the adjustment of 22 mm, medium values of 63.2% and 44.6%, respectively, in the recommended range. Thereby, the adjustment to 4 mm should be used to corn and sorghum ensilage with the evaluated harvester. The method used for determining the pricked uniformity allowed the evaluation with fastness, efficiency and simplicity.