RESUMO Durante o processo de colheita mecanizada de canade-açúcar, o desgaste das facas do mecanismo de corte basal é fator diretamente relacionado com a qualidade do corte realizado pelas máquinas, sendo o emprego de ferramentas

Statistical process control in mechanized farming is a new way to assess operation quality. In this sense, we aimed to compare three statistical process control tools applied to losses in sugarcane mechanical harvesting to determine the best control chart template for this quality indicator. Losses were daily monitored in farms located within Triângulo Mineiro region, in Minas Gerais state, Brazil. They were carried over a period of 70 days in the 2014 harvest. At the end of the evaluation period, 194 samples were collected in total for each type of loss. The control charts used were individual values chart, moving average and exponentially weighted moving average. The quality indicators assessed during sugarcane harvest were the following loss types: full grinding wheel, stumps, fixed piece, whole cane, chips, loose piece and total losses. The control chart of individual values is the best option for monitoring losses in sugarcane mechanical harvesting, as it is of easier result interpretation, in comparison to the others.KEYWORDS: quality, agricultural mechanization, moving average, EWMA. MONITORAMENTO DAS PERDAS NA COLHEITA MECANIZADA DE CANA-DE-AÇÚCAR POR CARTAS DE CONTROLERESUMO: O controle estatístico de processo aplicado em operações agrícolas mecanizadas representa uma nova maneira de avaliar a qualidade com que as operações são realizadas. Neste sentido, objetivou-se neste trabalho comparar três tipos de ferramentas do controle estatístico de processo aplicadas às perdas na colheita mecanizada de cana-de-açúcar, para determinar qual o melhor modelo de carta de controle a ser utilizado para este indicador de qualidade. O monitoramento das perdas na colheita mecanizada foi realizado diariamente nas áreas agrícolas, de uma unidade produtora na região do Triângulo Mineiro -MG, durante o período de 70 dias, na safra de 2014. Ao final do período de avaliação, foram coletados 194 pontos amostrais no total, para cada tipo de perda analisado. As cartas de controle utilizadas foram: carta de valores individuais, média móvel e média móvel exponencialmente ponderada. Os indicadores de qualidade avaliados durante a colheita de cana-de-açúcar foram as perdas do tipo: rebolo inteiro, tocos, pedaço fixo, cana inteira, lascas, pedaços soltos e totais. A carta de controle de valores individuais é a melhor opção para o monitoramento das perdas na colheita mecanizada de cana-de-açúcar, por apresentar maior facilidade na interpretação dos resultados, em relação às demais. PALAVRAS-CHAVE:qualidade, mecanização agrícola, média móvel, MMEP.

The quality control is used for the evaluation of processes and products, and it is important to detect and reduce variability and in operations management can be applied in mechanized harvesting of sugarcane billets. In this sense, this study aimed to identify critical quality indicators and, if necessary, to develop a continuous improvement plan for harvest of sugarcane billets. For the survey and definition of critical quality indicators the FMEA (Failure Mode and Effect Analysis) was applied, after the formation of the quality technical team. Evaluations of the collected variables were through control charts of individual values and the process capability indexes. There are 8 critical quality indicators in the billets harvesting process; the cutting height, the damage index, the percentage of non-viable buds and operating speed have greater importance for analysis due to the risk priority index and the easiness of obtaining data for analysis. The development of the improvement plan aims to reduce the variability due to crop billets, thus, making it able to perform the operation within the required quality standards.

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The mechanised farming operations, especially sugarcane mechanised planting, have diverse sources of variation that may harm the agronomic performance of the crop and destabilise the process, causing failure to meet operational goals. Accordingly, this study aimed to assess the quality of sugarcane mechanised planting in two operating shifts, on the left and right furrows, using statistical quality control tools. Mechanised planting was conducted in a farming area in the municipality of Monte Alto, São Paulo (SP), Brazil. The statistical design used was completely randomised, with plots subdivided in space, wherein 80 sampling points (replicates) were recorded during the day and night shifts, divided into 40 replicates on the left furrow and 40 replicates on the right furrow. The quality variables and/or indicators assessed regarding the performance of the mechanised set were the number of billets m -1 , total number of shoots m -1 , number of viable shoots m -1 , percentage of viable shoots, and billets consumption (Mg ha -1 ), for both furrows and operating shifts. The combined use of run charts and control charts has become essential to monitor the mechanised planting process more stringently, leading to greater reliability in decision-making and thereby improving future operations. The operation quality of mechanised sugarcane planting is affected by day and night shifts and is lower during the night period for all quality indicators, especially the left furrow.Keywords: operating shifts; quality control; Saccharum spp.; variability; agricultural mechanized. Abbreviations: AD_ value of the Anderson-Darling normality test; LCL_ lower control limit; LSL_ lower specification limit; m_mass of billets within the furrow; M ̅ R_ moving-range mean; Nb_number of billets; NNS_number of non-viable shoots; NVS_number of viable shoots m -1 ; Pd _planting density; BC_billets consumption; UCL_ upper control limit; USL_upper specification limit; X ̅ _individual-value mean; σ_standard deviation; % VS_percentage of viable shoots.

A B S T R A C TThe mechanized harvesting of soybean is a fundamental tool in the production process of this crop and, if not performed properly, it can result in severe mechanical damage to the seeds, causing significant losses at harvest, particularly due to reduced quality. Thus, this study aimed to evaluate the physical and physiological quality of soybean seeds at three speeds of the harvester, using statistical process control. The experiment was carried out in the municipality of Conceição das Alagoas-MG, Brazil, with three travel speeds: 4.5, 5.0 and 5.5 km h -1 . The seed samples were collected at 20 min intervals for 3 h of operation, with a total of 9 samples for each speed. The evaluations were performed based on the following parameters: grain temperature, water content, concave opening, cylinder rotation, mechanical damage and electrical conductivity. The physical and physiological quality of the seeds was dependent on the displacement speed of machine. The highest speed led to lower mechanical damage and higher vigor of soybean seeds.Qualidade física e fisiológica das sementes de soja em três velocidades da colhedora R E S U M O A colheita mecanizada de soja é fundamental no processo produtivo desta cultura e, caso não seja realizada adequadamente, poderá resultar em danos mecânicos severos às sementes, acarretando prejuízos significativos na colheita, particularmente devido à redução da qualidade. Neste sentido se objetivou, neste trabalho, avaliar a qualidade física e fisiológica das sementes de soja em três velocidades da colhedora, por meio do controle estatístico de processo. O experimento foi realizado em área agrícola, no município de Conceição das Alagoas, MG, com três velocidades de deslocamento da colhedora (4,5; 5,0 e 5,5 km h -1 ). As amostras de sementes foram coletadas em intervalos de 20 min durante 3 h de operação, totalizando nove amostras para cada velocidade. As avaliações foram realizadas a partir dos seguintes parâmetros: temperatura das sementes, teor de água, abertura do côncavo, rotação do cilindro, danos mecânicos e condutividade elétrica. A qualidade física e fisiológica das sementes foi influenciada pela velocidade de deslocamento da máquina. A maior velocidade apresentou menor valor de dano mecânico e maior vigor das sementes de soja. Key words:Glycine max (L.) Merrill mechanical damage vigor control charts Palavras-chave:Glycine max (L.) Merrill dano mecânico vigor cartas de controle

The mechanized sugarcane harvesting process is considered one of the major economic bottlenecks, with low operational efficiency and, mainly, high losses of stalks left in the field. In order to minimize these problems and assist in the improvement of processes, this study aimed to evaluate the losses in the mechanized sugarcane harvesting using statistical process control. The experimental design was completely randomized, based on the methodology of statistical process control with samples collected on five work fronts during the daytime and nighttime operation. The experiment was carried out in an agricultural area of a sugarcane mill in the municipality of Ribeirão Preto, SP, Brazil, on five sugarcane harvest fronts. Losses were measured using a 3.0 × 3.33-m frame, being divided into stump, loose piece + fixed piece, whole sugarcane, fragment, and total losses for each harvest front. The data were grouped into 50 weeks over the sugarcane-growing season, and statistical analyses were performed using the Minitab 16 ® software. Losses of loose piece + fixed piece were higher than the losses of stump, whole sugarcane, and fragment. The total losses showed higher and lower losses for the fronts F5 and F4, respectively, compared to the others.

Information about the capacity of the operation, harvest efficiency and performance of the harvester are of great importance in the management of agricultural mechanized systems, assisting in the decisions to be taken by the management aimed at its optimization. Mechanized harvesting was carried out at the farm located in Uberaba, Minas Gerais, in which eight repetitions for each evaluated plot format (irregular rectangular and trapezoidal) were performed. The activities of the harvester (harvest, unloading grain, harvest problems and climate pauses were monitored up. In determining losses circular frames were used with hoops made of 0.33 m², then were released soon after the harvester's platform passed, in pre-determined points. Two frames were located outside of the harvest machine (left and right) and a third was located between the rear wheelsets (centre). The total losses refer to the sum of losses on the platform and of the internal mechanisms. The rectangular plot allowed a better use of available time for harvest, and presented greater efficiency of time compared to the other plots. By contrast the irregular plot, showed reduction in relation the grain discharge logistics, when comparing with the others plots Among the losses were no differences in the formats of plots evaluated and to the sampling site, with samples taken at the centre of the harvest machine presenting less variability.