This study deals with a development of an eccentric type two stroke-cycle engine that the motion speed of piston can be changed in both of forward and backward direction.
This engine was able to change time areas of scavenging and exhaust ports by selecting the followings:
1. A suitable angle (a_A: after top dead center) of the crank-pin position, which its rotating center and the focus of an ellipse gear are both on one axle
2. A suitable eccentric rate (ε: rate of the eccentric length to the center distance of two ellipse gears).
By taking such measurements, the charging efficiencies and the performances (brake and indicated mean effective pressure) were improved fairly in comparison with the general purpose engine for industrial and agricultural machineries.
For example, at 4000rpm, a_A=150deg., ε=0.108, the brake mean effective pressure of the eccentric type engine was approximately better 13 percent than that of the general purpose engine.
Futher, the adaptability of the eccentric type two stroke-cycle engine will be discussed in the 2nd, 3rd, and 4th reports.

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To investigate the effect of soil resistance on side force of pneumatic tire at skidding, it was tried to calculate the value of total side force on the sum of the soil resistance obtained in another test and the side force of E. Fiala's theory. The applicability of the equation of total side force was discussed in comparison with the results obtained in the experiments on sand using smooth and agricultual tires.
Main results were as follows:
1. It was found at a level of 0.01 on χ²-test that the value of total side force agreed well with the experimental results.
2. The value of running resistance became large with the increase of rolling resistance on sand for small side slip angle, but the ratio of soil resistance to running resistance decreased for large side slip angle, though the value of soil resistance increased by the accumulation of removed soil.
3. The value of C, a factor of cornering coefficient, was affected by the coefficients of rolling resistance (r_a) and frictional resistance of sliding (μ₀). It became small quickly on concrete surface but gradually on sand with the increase of the value of r_a/μ₀. These showed the same tendency for smooth and agricultual tires, or powered and unpowered wheels without any load.
4. The value of C on powered wheel became small with the increase of tractive force. The relationship between C and the ratio of drawbar load to maximum tractive force showed the same tendency for smooth and agricultual tires on concrete surface and sand.
5. Agricultual tire of powered wheel with low inflation pressure was very useful for preventing the tractor from skidding on sand, because the values of side force and frictional resistance on tire were increased.
6. It can be said that the empirical equations ((12), (13) and (14)) obtained through these experimental results can be applicable for various soil conditions.

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This paper presents the equation of motion of a tracked vehicle with suspension equipments in order to study the lateral motions produced by steering control and its subsequent substantiation by means of scale model response tests.
The resulting agreement between theory and experiments was examined, and followed by consideration of the nature of the lateral response of the tracked vehicle to steering control.
As a result of the numerical analysis, the authors obtained the following conclusions.
1. In the study on rapid turning of tracked vehicles, the authors must use the mathematical model with a degree of freedom of rolling motion.
2. The radius at stationary circular turning increased rapidly when the outward shift of the location of the center of gravity of the vehicle incleased.
3. Trajectories in turning motion depended upon the initial velocity of the vehicles, at low speeds the radius of them increased as the velocity increased, but at high speeds they showed the oversteering characteristics.
4. The oversteering speeds decreased when the adhesion coefficient between tracks and ground decreased or the steering ratio increased.

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The (motion) equations of tractors attached with rotary tillers were developed based on some assumptions to study their dynamic behaviors. The main results were as follows:
1. The dynamic system in the horizontal direction should be taken into special consideration because the horizontal force F_H(t), which is transmitted to the tractor from the rotary tiller, was more influential than the one in vertical direction.
2. The linear spring-damper system in the horizontal direction might be proper as the dynamic model of the soil-tire system. The exciting force for this system was (mainly) due to the variation of the horizontal force F_H(t).
3. Three degrees of freedom were considered for developping the mathematical model. Those were the horizontal and the vertical displacements of the center of gravity and the pitch about the center of gravity of the tractor. Those were equations (26), (27) and (28). The angular motion of the power train system was not considered because the engine revolution was almost constant when the soil condition was uniform.
4. The developped (motion) equations were solved and compared to the experimental results. Good agreement was found between them from the practical view point of design technology. of tractors with rotary tillers mounted.

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The purpose of this paper is to find how the seeds were distributed uniformly through the seeding equipment consisting of a set of distribution system using pneumatic force. From the view point of studying distribution of seeds in the rising tube, the variation of the distribution around the upper part of the tube, and the effects of various factors on the movement of floating seeds were investigated, and following results were obtained.
1. The second flow was arisen around the plastic board at higher rotation of fan when the top of the tube was closed with a transparent plastic board, and for this reason, the distribution of aerial speed on a section of tube was similar to the distribution of the flow rate in the unsteady turbulence.
2. The minimum aerial speed required to transport seeds constantly was 8 to 11m/s.
3. The gradient of pressure was observed around the transparent plastic board attached to the top of the tube affected on the trajectory of seeds, except smaller seeds than rough rice, and the variance of the distribution became large.
4. When aerial speed was 22.5 to 24m/s, the seeds larger than rough rice at the transportation volume of 30g/s were distributed relatively uniformly on the cross section of tube, and the coefficient of variation of the distribution indicated below 15 percents.
5. The theory based upon the motion equation was used for the numerical calculation of the motion of floating seeds at a few transportation volume of seeds. In the case of soybean, of which the shape was almost spherical, the value obtained from experiment showed well agreement with the mathematical model (considering phenomena of collision affecting variance of the distribution). Further investigation is however necessary to express the behavior of seeds quantitatively, considering the phenomena of collision affecting the variance of the distribution.

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Studies were conducted for the establishing the method of evaluating the physical property of rice seedling mat, and for gaining data for designing the self feeding device of seedling mat.
Experimental results related to the coefficient of friction and the sliding angle of seedling mat, the bending deflection by dead load of mat, the deformation of mat by falling down and vibration and the effect of feeding speed on mat deformation, were/will be reported in part I and II.
After analyzing the results mentioned above, the measuring method of strength and toughness of rice seedling mat was established. A part of design standard for designing the self feeding device was also established.
As a type of self feeding device, a falling type of seedling mat with sequential automatic control was designed and tested. The relationship between mat sensor and its physical property was reported.
The sliding angle of seedling mat was approximately 45 degrees on flat metal table and 35 degrees on waved one.
The method of measuring the strength of seedling mat was proposed as follows;
to measure the deflection at a middle point of mat after supporting the mat for 30 second on span of 150-200mm long.
to measure the decrement of mat thickness after falling down from the height of 0.5 to 1.0m.

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Two kinds of root vegetables (radish and carrot) cultivated in three kinds of fields were prepared for discussing the effective factors on the pulling force of root vegetables. The various surface of main roots (3-236cm²) were given by the different sowing date.
From the results of experiments, the relationship between the pulling force (F) and the surface area of main root in soil (S) was expressed aproximately with a linear formula, F=aS+b, for various surface areas. The coefficient a in this formula was changed depending upon the soil properties and root vegetables.
Adhesion and cohesion were estimated for clarifing the effective factors on the coefficient a from the results of measurements of the moisture content and penetrating resistance. Adhesion and cohesion were considered to theoretical formula for the pulling force, f=1/2(K_aa+K_cc). The theoretical pulling force was calculated from f and S. The relationship between the theoretical and the measured pulling force was investigated. From the results of investigation, it was clarified that the pulling force was affected by the difference of the vertical distribution of adhesion and cohesion, rather than the difference of soil properties and kind of root vegetables.
It was estimated (from these results) that the theory discussed in the previous reports was signified as the basic rule on the pulling force of root vegetables.

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In this paper, the developments of the offset mower for sloped land and the results of field test by this machine were reported.
1. The constructed mower consisted of four portions; frame, mast, boom and cutting device.
The frame was mounted on the three point linkage of the tractor. The mast was set up vertically on the turn table of the frame and supported booms hanging the cutting device. The mast was able to rotate 180 degree about the axis of the mast. The boom, with two divided links, was actuated by hydraulic system and was able to position the cutting device. The boom could rotate about 135 degree in perpendicular. The cutting device had two types of blades rotary and reciprocating.
2. The developed unit was kept at the behind of the tractor and in the width of the tractor. So, the tractor with the developed unit mounted could travel well into or out of the orchards.
3. In the case of developed mower, the optimum speed was about 0.50m/s, which corresponded to eight times of the present equipment (bush cleaner) and hedging speed was about 0.3m/s. On the sloped land, rotary type was suitable for cutting withered and, fallen grasses and reciprocating type had a nice character as to the weight of the machine and the required horse power.
4. A shock absobing system employing coil spring inserted between turn table and main frame, was proved to be effective. An experimental cutter blade with free rotating bowl worked well on the rough surface of soil.

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The free courved roller conveyer descrived in this paper is, powered by the air pressure in the elastic pipe. The purpose of this study is to investigate the principle of the driving mechanism of this conveyor. Theoretical equations were introduced and compared with the static experimental model.
1) The floating hight of the elastic pipe contacting with the rear side of the load was determined by the equation (12), which can be led from the local change of the air pressure in the pipe. In the same manner, the floating hight of the pipe contacting with the front side of the load was determined by the equation (9). The results of the theoretical calculation were relatively coincident with the experimental values (Fig. 5, Fig. 6)
2. The rolling resistance of the load was measured by towing method and the rolling resistance coefficient was determined as the value of 0.026.
3. The equation (16) which gives the driving force of the load was obtained from the floating bight h₁, h_n and the rolling resistance coefficient. (Fig. 8)
4. From the investigations mentioned above, it can be concluded that the driving force of the load is relative to the air pressure, the weight of the load and the diameter of the pipe, and it is also inversely propotional to the length of the load.

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This study was done to measure the movement of the marked point and the shrinkage strain at the surface of brown rice kernels in the rough rice under drying. The measured planes were the length-width, the length-thickness and the width-thickness plane of the brown rice kernels. The authors made four (or six) small pits into very shallow layer of the endosperm of brown rice by fine needle from the surface of kernel of rough rice. The x-ray photographs were taken at a regular intervals during the drying of rough rice. So the authors put the least amount of 38% Urografin solution (contrast medium of blood vessel) into the inside of those pits and increased the contrast of reflex of x-ray photograph. Then, a small amount of the silicon grease was put on those pits and kept off evaporation from that place during drying. Those processed pits were used as marked point.
The following results were obtained through this study.
1. The marked points on the surface of the brown rice involved in the rough rice under drying were displaced to-
Three demensional center of shrinkage under drying: It was pressumed from the movement of marked points that the three dimensional center of shrinkage of rice kernel displaced to the fixed point 40% for the max. -length from the basal end on the center line of cellular disposition of rice kernel. It was suposed that this point was important to cause rice crack, and cracked position, and also to produce large shrinkage strain on the germ-end and perpendicular to long-axis on central part of rice kernel.
2. The principal strain on the length-width plane. The maximum principal strain: This strain was observed in parallel direction to the long-axis of this plane. In the case of sample 1 and 2, this strain was found in the direction of compression, and those values were enlarged with an increase during the drying time. In the case of sample 3, this strain was found in the direction of tension at early stage of drying. But some of them were found in the direction of tension until the end of drying.
The minimum principal strain: This strain on the central part of this plane showed smaller value than the one on the other part. This strain was increased in the part of dorsal side, the central part and the ventral side of the kernels in order. And the value of the ventral side showed double of the dorsal side.
3. The shrinkage strain on the length-thickness plane: This strain on this plane of the section of the ventral and the dosal part was larger than the strain of the plane of the central part. The strains of length direction (ε_x) on these planes in the ventral part and the dosal part were less than the strains in thickness direction (ε_z) on the same planes. The strains in both directionss of length and thickness, at the basal side on the plane of central part were lager than the strains at the apical side.
The shrinckage strain on the width-thickness planes: The strains in thickness direction (ε_z) on the basal side were lager than the strain on the apical side on this planes, and this tendency was simular to the one on the length-thickness planes. The strains of width direction (ε_y) on the central section were lager than the strains on the other sections.

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An experimental natural circulation type LiBr-H₂O absorption cooling machine was designed, fabricated, and tested for its performance to prove its feasibility in connection with solar heat energy source.
The working solar energy collecter-generator temperature was assumed to be approximately 70°C and the corresponding charge of LiBr-H₂O solution concentration was diluted to approximately 50% LiBr by weight.
The test results were summarized in Table 2 and the overall coefficient of heat transfer in each heat exchanger was given in Fig. 7. The test results suggested that in order to obtain longer and better thermosiphon effects so that the overall capacity of the machine would be improved, a combined collecter-generator should replace the bubble column generator which was employed in the test machine.

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In this paper, the Direct Search Method developed by Seinfeld and his co-workers was applied to simulate a control problem for crop production.
The example is assumed to be a problem of maximizing profit by picking off one plant, when plant community is composed of two plants, such as crop and weeds. Control decision is on-off control, that is only able to be taken weeding or not weeding. Performance index, evaluate total weight of yield and yield effiency, can be obtained as the sum of its component, each of which is multiplied by weight parameters.
Three typical cases, different from weight parameters, are simulated by computer. It is difficult to compare the result to actual crop production, because the model is simplified and has many restrictive condition. But it seems to be reasonable from the point of view of ordinary experience in crop production. General community control model was introduced in the first report of the same title and much argument has been made in the subsequent reports. It seems to be possibile to discuss many problems, not only in modeling of the field ecological systems but also in analizing crop production problems.

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