By use of slip-line method, the authors have been studying the bearing capacity of Coulomb plastic bodies in various shapes. In the practical problems such as the bearing capacity of farm soils or the indentation resistance of rigid punches into metals, the width of loaded materials is not generally wide enough to be regarded as a semi-infinite body. In the previous papers, the bearing capacity of the infinite body in the shape of a truncated wedge and that of quarter to semi-infinite bodies subjected to a strip load were elucidated and verified by some experiments.
Further, the bearing capacity of an infinite body in the shape of a truncated wedge with finite height has been analyzed in this paper. The assumed slip-line fields are as follows:
i) When
ω≤{1+2cos(μ-φ)/cosμexp(ξtanφ)}(≡ω^p), (1)
the Prandtl's field shown in Fig. 1 holds. In Eq. (1), ω designates a ratio of the loading width w to the top width W of the wedge, φ is an angle of internal friction and μ stands for
μ=π/4+φ/2(2)
ii) When
ω>ω^p…(3)
and
h≤tanμcosξexp(ξtanφ) (≡h_c), …4)
the slip-line field shown in Fig. 2 holds. In Eq. (4), h denotes a ratio of the loading width w to the wedge height H and ξ is a spreading angle of the spiral slip-line region.
iii) When
ω>ω^p…(5)
and
h>h_c, …(6)
the slip-line field shown in Fig. 3 holds. This slip-line field cannot be expressed analitically. Therefore the bearing capacity must be calculated by a numerical method.
iv) As ω or h becomes larger, the slip-line field shown in Fig. 4 holds. The bearing capacity q is given by
q=q₀{1+H/wtan(H-w/2H+tanγ)}, …(7)
where q₀ is the bearing capacity of semi-infinite body and γ is the angle given by the following equation.
γ=tan^-1(W-w/2H+tanΦ), …(8)
where Φ stands for a spreading angle of the wedge.
The calculated results of the bearing capacity are shown in Fig. 7 (a)-(c) for γ=0°, 30°, 60° and internal friction φ=0°, 15°, 30°. From these figures, it can be said that
1. The larger γ, the larger is the bearing capacity.
2. The bearing capacity is constant for a small value of h. Thereafter, in case of γ=0° the bearing capacity increases to constant value q₀. In case of γ>0° it increases to the crossing point of two curves calculated by the field shown in Fig. 3 and Fig. 4, and then decreases asymptotically to constant value q₀.

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The magnitude and distribution of soil pressure exerted on the surface of horizontal screw type blade were experimentally examined and the theoretical equation for cutting resistance was derived.
(1) The variation of soil pressure during one revolution of the blade was measured miniature load cells attached to the blade. The soil pressure at the joining point (A) of the vertical cutting blade and the cutting blade wass largest among five measuring points, and the time during which soil pressure was exerted was also longest. The variation of cutting torque almost agreed with the magnitude of soil pressure at the point A.
(2) In case of sand with small cohesion, the distribution of soil pressure was the same as that described above, but the torque was nearly constant.
(3) In case of the semi-infinite cutting width, the soil pressure on the turning blade turns out to be extremely large. The cutting action under this condition may occur actually, and attention must be paid regarding the strength of the blade.
(4) The soil pressure exerted on the surface of the blade was large on the cutting blade, and among others, it showed the largest value at the joining point of the vertical cutting blade and itself, while it was extremely small at the points C and D. Also the wave forms of the soil pressure and the torque corresponded. From the reasons described above, it was concluded that the cutting resistance of a blade is produced by the tip of the cutting blade, and the main factor is the shearing resistance of soil. Consequently, the theoretical equation for the cutting resistance was derived, assuming two dimensional cutting under the revolution at a fixed position. The tiling power and the forward component force agreed with the experimental values.

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Head loss due to mixing of pesticide liquid in the auto-dilution equipment was considered in this study. At first, on one method in order to inflow at the best condition, inflow angles were 45 and 90 degrees, and sectional area ratio of main pipe to side pipe was 1.0.
A little effects of an inflow angle on the dilution ratio appeared for nozzle diameters of 0.5mm and 1.0mm (Fig. 4). Then, the head loss increased in proportion to pesticide liquid pressure and nozzle diameter at the inflow angle of 90 degree. On the other hand, it increased in order of 0.5, 1.0, 0.7mm of nozzle diameter at the inflow angle of 45 degree (Fig. 5).
Head loss at the nozzle was regarded as one kind of loss due to sudden contraction, and this trend was linearly increased with the rise of pesticide liquid pressure, and increased in order of 0.5, 1.0 and 0.7mm of nozzle diameter.
These results were consistent with the experimental results at head loss of inflow angles of 45 and 90 degree. These data can be available for designing the mixing parts of auto-dilution equipment.
The two dimensional comformal mapping for potential jet flow was applied for the downstream of the nozzle near the outlet of water pipe. This revealed that highly turbulent flow of liquid and gas phases was developed and unsteady two dimensional flow was also seen around it. This results showed the complicate mixing flow of liquid and solid.

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In the process of the development of a lotus-roots harvester by water jet, the distribution, the property and the strength of lotus-roots were revealed. The results were summarized as follows.
1. The growing depth of lotus-roots at harvest time varied with the variety, the method of culture, the condition of soil and others. But in this study internodes distributed in the depth of 15-40cm and terminal buds in 10-40cm. The growing depth of winter lotus-roots distributed in wider range than that of summer lotus-roots. Therefore, in order to harvest lotus-roots perfectly, it was necessary that soil was digged and was liquidized by water jet to the depth of 40cm.
2. The specific gravity of internode, intercellular spaces of which were filled with water, was 1.0-1.2 and that of node was 0.85-0.98. Therefore, lotus-roots would not float in the water if intercellular spaces of internode were filled with water. If intercellular spaces of internode were filled with air, lotus-roots would float in the water. The specific gravity of primary lateral shoot (class M, S, 2S) or secondary lateral shoot (class 2S) was smaller than that of main shoot (class L), and that of lotus-roots was smaller in the back part. But when lotus-roots were floated by water jet, the terminal bud and the first part of internode floated at first by the influence of nodal root in the third node and its following nodes.
3. A straight relation was found between the specific gravity of internode filled its intercellular spaces with air and the space ratio (=intercellular space volume/intercellular space volume+flesh volume), and the specific gravity decreased in proportion as the space ratio increased. The space ratio of main shoot was smaller than that of primary or secondary lateral shoot and the space ratio of the first part of internode was 20-30% and that of the last part of internode was 40-50%.
4. When compression stress was applied to the internode, the strain increased gradually and the first destruction occured. The compression strength meaned the stress to occur the first destruction. The compression strength of internode was 7-20kg/cm². The compression strength of the upper side of internode was smaller than that of the lower side. It was the smallest in the upper side of the first part of internode. But the compression strength of internode was generally large and bad influence by water jet or travelling machine was not found.
5. The maximum bending moment of main shoot was 15-22kg-cm, and that of primary or secondry lateral shoot was 4-8kg-cm. The maximum bending moment of the second node was the largest. The bending strength of node was 3.8-7.8kg/cm².
6. The broken loss of lotus-roots often occured by smaller energy than the energy of water jet to dig and liquidize soil. Therefore, in order to prevent the broken loss, it was necessary to decrease the number of hitting lotus-roots by jet as much as possible.

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Based on the results obtained in Part 2, the effect of incorrectly filed saw chain tooth which lately has become a major point of interest among the people involved in forest operations, was investigated in this report. Taking five kinds of remodeled cutter teeth in which one of the functional factors was filed incorrectly, experiments were carried out according to a similar procedure as described before. The magnitude of the difference of cutting resistance forces between the tested cutter teeth and the standard teeth was examined. The results were as follows:
1) The relations between the velocity ratio λ and the tangential cutting resistance force F_H and the normal cutting resistance force F_V were expressed by hyperbolic curves same as the results obtained in the previous report.
2) The relation between the velocity ratio λ and the force ratio F_V/F_H which is equivalent to the angle of resultant cutting force was a straight line as shown in Fig. 7. Comparing these five regression curves it was clear that the force ratio was proportional to the velocity ratio and differed in its magnitude as shown in Fig. 8. In other words, it can be said that the type of back slope on the side plate cutting edge aggravates the worst due to incorrect filing, this followed in the order of the blunt type of the top filing angle, the blunt type of top plate cutting angle, the type of hook in the side plate cutting edge, and the type exceeding the depth gauge.
3) A similar tendency as described above can be seen in the relation between undeformed chip thickness δ and specific cutting resistance force f_H and the specific normal cutting resistance force f_V Above all the lattar appears clearly.
4) When a square-shaped cutter tooth is filed with a round file, other dimensions may be changed. Therefore, when cutter teeth are resharpened to maintain their original dimensions, special attention should be paid to the functional factors provided with each cutter tooth.
5) In other words, points to which special attention should be paid are the top plate cutting angle, top plate filing angle and depth gauges in that order. From the view point of proper filing method, as a matter of course, each cutter tooth on the whole saw chain must be maintained at their original dimensions.

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The purpose of this study was to develop the mechanism which provides the air jet only against the bottom surface of a carrier pallet to lift up.
The results of the fundamental experiment and hovering experiment can be summarized as follows;
1). The response time of the piston sensor was calculated from the following equation.
t₁=S_p²ρ/μ″F_pgk₁(√2g/ρ(P_p-m+α/S_p)-√2g/ρ(P_p-m+α+k₁y₁/S_p))
2). For the experimental apparatus, the minimum pressure on the piston sensor head was obtained to be 0.02 P₀ as the theoretical value.
However, since the apparatus actually had various mechanical resistance, the value obtained in Fig. 6 was desirable. (Ref. Fig. 6)
3). It was concluded that factors to decide the consumption of the air were the diameter of the air flowing hole, the height of the lifted pallet, and the air pressure under the lifted pallet.
The pressure in the main pipe P was the most effective factor to decide the air consumption. (Ref. Fig. 12-15)
4). The successful operation was obtained under the condition that the air consumption rate was over 1400l/min.
In this case, the friction coefficient was less than 0.02. (Ref. Fig. 17-18)

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The effects of the set of rollers design and material in a hay conditioning process was investigated. In laboratory scale tests the upper rollers position was fixed, while the lower rollers were mounted on a pivoted support which allowed to apply a force directly on upper rollers by the hydraulic system. Both rollers could operate independently. Six sets of rollers combination, with 220-240mm in diameter and 100mm in length, were designed as presented in Table 1. The loading force of the rollers was 23-90kg while the speed was 30-120rpm. After running the samples through the conditioning rollers, samples were placed in the drying chamber (30°C, RH 65%) to obtain the results of the drying test. Freshly cut Orchard grass and Red clover were used in the tests. The results were as follows:
1) Mechanical dewatering response of the conditioning rollers was affected by the rollers material (steel and or rubber). For the first cut the set of steel rollers gave maximum drying for Orchard grass and Red clover, while a combination of steel and rubber rollers provided minimum drying for both forage crops.
2) Dewatering response had a trend to increase by an increase of the rollers loading. However the moisture loss was low, hence often could be neglected.
3) The rollers treated grass had a higher rate of drying than that of untreated grass. The relation of moisture content to drying time was a linear response, from the initial to a given moisuture level, when it was plotted on a semi-logarithmic graph and expressed by a variant exponential equation.
4) In case of a set of smooth rollers the highest rate of drying was achieved by a combination of steel and rubber rollers for Orchard grass and by a set of steel rollers for Red clover, while a set of rubber rollers provided the lowest rate of drying for both forage crops.
5) A combination of ribbed steel and smooth rollers of steel or rubber, or a set of corrugated rubber rollers provided a high drying rate only by the use of corrugated rubber rollers for the first cut of the Orchard grass and Red clover, while for the second cut the drying rate was only slightly affected by the choice of the rollers.
6) The rate of drying was only slightly affected by the number of the ribs and corrugation of the rollers applied.

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This experiment was made to clarify the load characteristics and to know the horsepower requirements on the rice hull soft-expanded instrument driven by the power take-off (pto) of a farm tractor. The results obtained were as follows.
(1) The soft-expanded rice hull was visually satisfactory in quality at the capacity which was more discharged on 1-8 of the other notch numbers, except 170kg/h of the smallest discharge capacity when a variable speed motor attached for varying the capacity rotated on 0 mark in the notch number. In the case of too small capacity to flow evenly, it has sometimes been clogged at the part which was pressed hard on a compression shaft. The material which was concentrically distributed between 1mm and 3mm in screen size before processing changed to which was uniformly distributed in the wide range between 0.5mm and 4mm by sifting through several screens. And comparing the both distributions of weight percentage of rice hull soft-expand-ed in the case that the clearance of a discharge port was regulated 7mm and 4mm, the case of 4mm was a little finer than another.
(2) When loading on the pto shaft with increasing the feeding rate of material, in the case of 7mm the rotational speed of a pto shaft slowed down only by about 4rpm in steady rotation and a torque rose only by about 3kg·m in an average peak value at the discharging rate between 170kg/h and 300kg/h, the speed reduced hastier and the torque rose up to 27kg·m at 350kg/h, and further the speed slowed down fast with large fluctuations and the torque reached to 35kg·m at 500kg/h. And in the case of 4mm the speed slowed down with a constant rate and the average peak value of torques was about 10kg·m larger than that in the case of 7mm, the differences between the average peak values and the average bottom values of each torques were about 8kg·m on an average.
(3) The rotational speed had a tendency to slow down rectilinearly with increasing torque. Now if comparing this correlative graph with a curve of the torque which have previously measured with a dynamometer on the same tractor used for this experiment, it was known for the pto torque curve to lie between the average peak values and the average bottom values of torques within the range of partial load. Consequently, it was seemed proper to apply an average torque in calculating the horsepower required for driving this instrument, but the small torque of about 1.5kg·m had already acted on the pto shaft even without feeding, so it should be rather better to use the average peak value. And the rotational speed to each torques should be assumed to be all at 540rpm, because it is necessary to keep its rotational speed constantly while operating under various load conditions.
(4) The relations of the horsepower requirement to the discharging rate were that in the case of 7mm the horsepowers required 12ps to 15ps between 170kg/h and 300kg/h, 20ps against 350kg/h, 30ps against 500kg/h in the discharging rate, and that in the case of 4mm these required 18ps against the smallest rate of 150kg/h, 31ps against the largest rate of 390kg/h.
Consequently, it was desired to require for this instrument about 30ps in the highest horsepower of pto shaft against the largest discharging rate, but if we were expected to keep continuously operating within the range of partial load in torque curve of a tractor, it should be to require 36ps in consideration of the load factor of 1.2 obtained in this experiment.

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A study of the possibility of separating of unhulled rice (paddy) and brown rice by winnowing was carried out, in which the aerodynamic properties, such as terminal velocity, the flying distance and the distribution of grains were investigated and the limit of winnowing was considered.
The main results were as follows:
1. The terminal velocity of grains which was measured by floating a grain in the ascending air current was 5.8m/s for a meaty paddy of 30mg and 6.7m/s for brown rice of 25mg, respectively. The relations among the terminal velocity V_t(m/s), the weight G(mg) and the projection area A(mm²) of a grain were as follows;
Paddy; V_t=4.8(G/A)^1/2-0.08
Brown rice; V_t=5.3(G/A)^1/2-0.92
All of paddy and light unmatured brown rice under 18mg floated in the ascending air current of 6m/s.
2. The drag coefficient and the terminal velocity of grains varied with the flying posture, and they were maximum when flew in the direction of Z and X axis of grain respectively, as shown in Table 4. As the terminal velocity in free posture almost coincided with that of grain flying in the direction of Z axis, it seems that most grains float and ascend holding the same posture in the air.
3. The equivalent diameter of spheres calculated from the terminal velocity were 1.47mm for a paddy of 30mg and 1.56mm for a brown rice of 25mg, and those values were 0.65-0.75 times of grain thickness L_Z.
4. The flying distance and the standard deviation of distribution of grains in the horizontal air current are about in proportion to the second power of the air velocity, and the changing rate according to the increase of the velocity was somewhat larger in the latter than the former.
5. The measured value of the flying distance coincided nearly with the calculated one. From this fact, it seems that grains fly holding the postures of Y or Z axis in the direction to the horizontal air current.
6. To show the degree of grain separation by horizontal air current, the wind separating ratio R_S was defined as follows;
R_S=l₁-l₂/S₁+S₂
where l₁, l₂; the average flying distance of paddy and brown rice
S₁, S₂; the standard deviation of distribution of paddy and brown rice
The value of R_S increased with the height of the air outlet of the experimental apparatus. In the case the heights were 10-12cm, R_S took the largest value near the terminal velocity of paddy and brown rice.
7. In this experiment by the horizontal air current, the value of R_S was 0.3-0.45, and 20% of paddy fell within the average flying distance of brown rice. Therefore, if the material contains 5% of paddy initially, more than 2% of paddy will be in brown rice after winnowing. From these results, it seems to be very difficult to separate paddy and brown rice more strictly only by winnowing.

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To establish a method of energy evaluation of grain drier in consideration of moisture concentration energy, the author measured and arranged the fundamental thermal properties of rough rice and proposed new equations of enthalpy and equilibrium moisture content of rough rice.
1. Thermodynamic relations between specific heat, heat of wetting, equilibrium moisture content and enthalpy of grain were discussed.
2. Specific heat of dry matter of rough rice was measured and arranged (Table 1-1).
3. Equilibrium moisture content of rough rice (Nihonmasari) conditioned by saturated salt solution method was measured (Table 1-2). From the data, the coefficients of Strohman and Yoerger equation were obtained by Othmer method and this equilibrium moisture content equation of rough rice (eq. 1-28) was fit for a wide range of temperature and humidity.
4. Heat of wetting of rough rice was obtained by Othmer method. The data were compared with those of previous studies and discussed (Fig. 1-5), and equation of heat of wetting (eq. 1-26, 27) was obtained.
5. Enthalpy equation of rough rice (eq. 1-29) was obtained in consideration of heat of wetting which is based on moisture concentration energy. By this equation, the enthalpy-moisture concentration diagram of rough rice (Fig. 1-6) was drawn up.

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The estimation of stresses in a rice kernel will be necessary for discussing the stress cracking in the kernel. A few studies have been reported for the stress analysis in biological materials. Those studies, however, can not be applied to estimate the stresses in the rice kernel because of the insufficiencies on the description of the analysis. In this paper, a calculation method was presented for the stresses in a rice kernel which could be assumed to be a linear viscoelastic sphere under the influence of a radial moisture distribution.
As shown in the previous paper, the stress-strain relationships for the rice endosperm were those for a continuous Maxwell viscoelastic body with temperature and moisture dependent properties. It could be assumed that the rice endosperm was thermo- and hydro-rheologically simple. The present analysis would be based on the generalized relaxation integral law which was applicable to the thermo- and hydro-rheologically simple materials such as the rice endosperm, but the dilatational response of the rice kernel would be purely elastic. A finite difference method was applied to the calculation of the relaxation integral law.

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This investigation was carried out to find out the properties of adsorption phenomena of barley, which occurs locationaly at the beginning of deep bed drying and air circulation in the storage bin.
Authors studied experimentally static adsorption phenomena of barley and the following conclusions were obtained;
1) The method of using a saturated aqueous solution of salt was not so suitable to static adsorption experiment as that of using a aqueous solution of H₂SO₄ because of poor control of humidity.
2) An adsorption process after the time quite passed was described as the exponential equation.
3) The influential factors on the process were both, intra-particle and fluid-side mass transfer over the range of this investigation and the measured values of this investigation couldn't be compared simply with experimental data of drying because of differences in the factors.
4) The relationship between adsorption constant defined as K_ad and temperature was described as Arrehnius equation in the range of 40 to 70%rh.. It was also found that the adsorption constant depended on the humidity.
5) The modified experimental equation of equilibrium moisture curve was developed and the predicted value by the equation was in good agreement with the measured value over the wide range of relative humidity. The modified equation was described as;
In Me=a₀+a₁x+a₂x²
Where, x=In(-In (1-φ))
6) The heat of adsorption was described as the following equation derived by Othmer method.

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Fresh tea leaves change physically and chemically into green tea during the manufacturing process.
1. Tea leaves did not indicate any delayed light emission (DLE) in the processing stages, from the end of tea steaming to final rolling. DLE of tea leaves appeared in the drying stage, increased with time of drying and maintained an almost steady level at the latter stage of drying (Fig. 2).
2. DLE was detected for the first time when the moisture content of tea leaves decreased to about 10 percent (w. b.) in the drying stage (Fig. 3).
3. The DLE spectrum of crude green tea when excited with xenon flash had a primary peak at the wavelength of 565nm (Fig. 5). The DLE was found not to have been emitted from chlorophyll a, but the constituents which emitted the delayed light are yet to be identified.
The fundamental characteristics of DLE for crude green tea were measured as follows.
4. The DLE of crude green tea did not show the “dark recovery”. DLE intensity of crude green tea showed a bit of high value under the shorter dark period and was not affected by dark periods longer than 1 minute (Fig. 4).
5. The DLE of crude tea differed from that of fresh tea leaves and increased proportional to the increase in exciting light intensity (Fig. 6).
6. DLE intensity of crude tea decreased inversely with increase in tea temperature from 12.5 to 45.4°C, and became feeble beyond 40°C (Fig. 7).
7. Fundamental characteristics of DLE of green tea showed similar patterns for Gyokuro, Sencha, and Bancha which were superior, medium, and coarse in quality respectively.
DLE as a means of quality evaluation of crude tea.
8. The DLE intensity of the crude teas wass high in the following order, Gyokuro, Sencha, Bancha respectively (Fig. 8).
9. The quality of Gyokuro and Bancha as pre-determined by their wholesale prices, had a significant correlation with the DLE intensity (Table 2 and 4).

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Composting experiments were performed with the compact experimental device which had been shown in our previous report.
Effects of waste properties and ventilating ratio on maximum temperatures of the materials and values of moisture losses were investigated. The results were as follows;
1. Carbonated husk was considered to be more suitable for the property reformer than sawdust which had been used generally, since it had a good effect on temperature rising of material and did not need such a sufficient treatment for decomposition of lignin as the sawdust needed.
2. Under the moisture content which was as high as that of raw manure, the fermentation resulted in wrong condition with property reformer whichever was chosen from the two (Fig. 1). It was confirmed that moisture content around 65% on wet basis was an upper limit for the effective composting when property reformer was used.
3. In the case of initial moisture content as high as that of raw manure, more than 15% property reformer to fecal wastes was needed in order to perform its function (Fig. 2). The result showed that considerable quantity of property reformer had to be mixed into fecal wastes in order to produce suitable waste condition to composting operation.
4. Experiments which were assumed that manure existed together with urine were performed. The results showed that mixing of urine gave a good effect on composting (Fig. 3 & 4).
5. The dry matter loss which brought about from fermentation had a considerable close correlation with the mean value of material temperature (Fig. 6). The material temperature which was equivalent to a result of thermo balance between fermentation and drying seemed to influence on decomposition rate of material ready to be resolved.
6. Condition for certain generation of high temperature was considered to be a range of ventilating ratio from 0.3 to 1.0l/min. per 1kg dry matter of mixed material, when maximum temperature of material was regarded as an important factor. While, the fermentation hardly occurred in ventilating ratio more than 5l/min. per 1kg dry matter.
7. Optimal ventilating ratio for decreasing moisture ranged from 1 to 3l/min, per 1kg dry matter. Regarding the result of former clause, ventilating ratio about 1.0l/min. per 1kg dry matter was considered to be optimal for rising temperature and decreasing moisture.

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