Productivity Optimization of Screen House Layout Design

The study investigated the optimization of the screen house design to improve the growth productivity of green ornamentals. It focused on the labor-intensive handling operations in order to minimize the time invested in these operations and to maximize the total revenue. The research was performed during 2006–2007 in two modern farms in the central part of Israel. The farms contained 7 and 11 ha of Pitosporum and Aralia screen houses. The various stages of harvesting on each farm were subjected to work studies and time measurements, and a computer simulation model was developed with the ARENA 7™ to find an improved screen house layout. The main goal was to determine the time per stem and hourly output per worker as functions of length of row, distance between rows, distance between plants, work pace, and number of workers. Results show that for the examined cultivars and the present working methods, the best outcome was reached when the row length was the shortest of those examined. There was a decrease of 35% in output when row length increased from 24 to 200 m. Simulation results showed that the best length of a screen house was 24 m. Furthermore, the best width of the screen house was determined as a function of the number of workers and their work pace. In addition, the optimal location of the cart used to transfer the crops to the packaging house was determined

Working planning in packing houses of flowers mixed farms to increase the yield

The study deals with performance improvement in flowers mixed farms.  The farm under investigation is located in the central part of Israel and grows three types of green ornamentals: Pittosporum, Aralia and Aspidistra.  The farm consists of 8 hectares and employs 7 workers.  The annual yield of the farm in 2009 was 3.5 million branches.  The study investigates the working processes of the packing house.  A computer model and work planning management tool was developed using MATLAB.  The model inputs are: flower type and quantity, due date and sales price.  The output is a work schedule.  Results show an improvement of processing time by: 47% for Pittosporum, 19% - 45% for Aralia, and 23% - 54% for Aspidistra

Development of a weight-based technique for ‘packages labelled by count’ of agricultural products

Accurate weight-based packing of ‘packages labelled by count’ necessitate very low coefficients of variation of unit weight. For agricultural products with relatively high coefficient of variation, the usual weighing methods are therefore not suitable. In this paper, a method that supports the count-to-weight transform of pre-packed packages of products with wide variability of characteristics is presented. The developed innovative weighing method utilises a weighing procedure where the coefficient of variation of the product's unit weight is used in order to determine the critical package weight and to comply with the package nominal definitions. The method involves a weighing procedure of ‘packages labelled by count’ which is based on a mathematical model which reduces the variability in package size and eliminates the cases of under filling of packages. The method was validated experimentally. The results revealed that the variability of package size is high when counting manually. In contrast, by implementing the proposed method the standard deviation of the quantity in a package was reduced by 30%. Moreover, the number of packages with quantity less than the nominal was reduced to zero. In general, the developed method can be applied when the coefficients variation is high and the counting procedure is inaccurate and/or expensive