The purposes of this paper are to clarify the influence of the size of shear ring grouser on the shear constants of soil, and to find a suitable calculation method to get shear constants. From the experimental results, it was found that the grouser size influenced on the apparent value of soil cohesion in proportion to the ratio of the area moments of the ring peripheries of grouser sides to that of ring bottom. The influence of grouser size on the internal friction angle was small, since the normal stress on a shearing plane changed with grouser size. The equations of shear stress, containing the areas and the area moments of the peripheries of grouser sides, were used for getting shear constants of soil.

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The objectives of this paper are to develop the equations of motion of tracked vehicles with independent suspension equipment and to predict the characteristics of cross motion of the vehicles on a slope. An analytical model that involved sliding and handling behaviors of the vehicle on a slope was proposed and verfied experimentally by using scale model tests. As the results, the validity of the numerical model was experimentally verified, and it was clarified that the characteistics of tracked vehicle in crossing a slope were affected considerably by the inclined angle, the position of center of gravity, the frictional coefficient of track-ground contact and the load distribution under road wheel.

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One of the most typical turning methods of commercialized combine harvester is the conventional pivot turn. This turning method sometimes decreases the overall operation efficiency of the combine harvester. To solve this problem, the various turning methods such as pivot turn, spin turn, soft turn and turntable turning method were discussed. Operation efficiency of a combine harvester using the above turning methods was evaluated based on theoretical computation, and their performances, during harvesting operation were compared. The optimum turning method for combine harvester in the actual harvesting operation in the paddy field was proposed.

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In order to derive the effect of the motion of furrow slice on the inverting performance of plow, the locus, the speeds and the accelerations of furrow slice were analysed. The soil was treated as a rigid model in the analysis.
Acceleration components of the furrow slice were measured in x, y and z directions of moving coordinates by an accelerometer set in the furrow slice, and the acceleration was calculated with the transformation formula based on a rigid scale model. Furthermore, the values of soil displacements in x, y and z directions, calculated from numerial integration of accelerations, approached to actual values. It demonstrates that the acceleration measured corresponds to actual values. Effects of acting forces on soil displacement were studied.

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An automatic machine for continuous coating of seed with alginic acid has been developed and tested. The machine controls the flow of seed automatically with negative pressure and suction type feed mechanism. The physical properties of gel-coated seed made with the machine were tested for compressive breakdown. It was found that the thickness of the gel-coating can be controlled by either the operating speed or the stroke of the plunger, or both, and that the surface hardness of the gel coating is determined by soaking time.

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This study aims at applying Helmholtz resonance phenomena for measuring the volume of agricultural products. This report deals with an volume measuring system by acoustic method and its precision and accuracy of prediction. As a result of measuring water volume by this system, the predicted values agreed very well with the apparent values and the coefficients of determination were greater than 0.99. It was proved that the larger the volume ratio of a sample to a Helmholtz resonator was, the higher the precision and the accuracy of prediction were. The volume of grapes and apples were predicted with another bigger resonator and the coefficient of determination between the predicted and the apparent values was 0.968. In this case the coefficient of determination was slightly smaller than in predicting water volume. From a point of view of precision and accuracy, however, this volume measuring system is very effective for determining the volume of agricultural products.

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Driving force for moisture transfer can be conceptually increased by maintaining head space at very high or very low vapour pressures. Under subatmospheric pressures the sorption resistance due to interstitial air within a kernel of grain is low. Using this concept, the adsorption and desorption properties for polished rice, which can be used in commercial moisture adjusters to get even sorption in a batch, have been measured under reduced pressure for theoretical interpretation of the process. Higher uniformity of sorption was found at lower vacuum levels in thick layer sorption. Sorption coefficient “k”, in the first falling rate period moisture transfer equation, was calculated for one-seed layer at different temperature and vacuum levels. Grain damage due to low pressure was also investigated.

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By the typhoon 9119, a large number of trees was felled and broken in the forest around Hita city. In this study, the damaged forest area was extracted using satellite data. First, the sunny and the shady parts of the forest were identified using the satellite data obtained before the typhoon. By applying the data to the data after typhoon and treated using RVI and NDVI, the area of the felled and broken trees were identified. The obtained results showed the same accuracy as the data examined manually in mesh divided areas. It was shown that the analysing method using the remote sensing data can offer the simultaneous data over wide area where data are hard to obtain.

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