Principal factors influencing the power performances of an air-and charge-cooled Wankel rotary engine for general use are gas seal clearances, the number of side seals, etc. which were discussed in the previous report. Besides these, there are many other factors, such as 1) constructions of the main induction mixture passage, 2) shapes and locations of a recess provided on the rotor flank, 3) positions of a spark plug, etc.
Experimental and theoretical investigations were done on the relationship between these factors and power performance. The results may be summarized as follows:—
(1) Air-and charge-cooled Wankel single rotor engines can be classified as 1) engines in which three holes provided just under the apex slots of the rotor are used as the main induction mixture passage, and 2) ones in which three holes provided on the rotor journal of an eccentric shaft are used as the main passage. As far as the engine power output is concerned, the former has an advantage of 8% over the latter (Fig. 1, 2).
(2) The optimum shape and location of the recess by which higher engine power output can be produced are the circular arc shape recess in which the deepest arc bottom provided on the rotor flank is located at a short distance to the leading side in the direction of rotation from the minor axis. From the results of the experiment using the RX67H 67cc engine, the power output of the engine equipped with the rotor having circular arc recess had the advantage of 7-8% over that having straight recess. (Fig. 3).
(3) In a single spark plug engine, the spark plug should be installed on the leading side in the direction of rotation from the minor axis so that higher power output may be produced. The power output of the engine in which the spark plug was located E=7mm from the axis had the advantage of about 7% over that of E=10.5mm (Fig. 4).
(4) Effective measures for transfering the maximum torque point to the low speed side are, 1) decreasing of the venturi-tube diameter of carburettor, 2) advancing of inlet port closing, and 3) delaying of ignition timing, etc. However, these measures will substantially decrease the power output in high speed range, and the improvement of the torque characteristics in low speed range cannot be expected so much. For this reason, the optimum measures for improving the torque characteristics in low speed range are, 1) reducing of the friction loss of gas seals and 2) minimizing of the quantity of escape gases past the sealing devices out of working chambers (Fig. 5).
5) Due to the high concentration of thermal stress occuring around a transfer hole connecting epitrochoidal surface with the electrode chamber of a spark plug, there is a possibility of thermal deformation occurrence within a certain range around the transfer hole. It was found from the experiment that the deformation was stopped when it reached to t=4.5mm. As the electrode part, however, is apart from the epitrochoidal surface of the combustion chamber when the thickness t is increased too much, the gas exchange between the combustion chamber and the electrode chamber is not smoothly done. Therefore, difficult problem will arise such as the deterioration of combustion characteristics at part throttle load (Fig. 6, 7).

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Influences of different geometrical shapes of annuli on measuring soil frictional stress were investigated:
1. The soil-annulus system was defined using the dimensionless Pi terms as: π₁ or π₁′=f(π₂, π₃, …, π₈) in which π₁=S/ρV², π₁′=F/ρV², π₂=h/b, π₃=b/d, π₄=λ/d, S is soil-shearing stress, F external frictional stress, ρ bulk density of soil, V frictional speed, h grouser height, b section width of annulus, d mean diameter of annulus, λ grouser span.
2. The component equations relating π₁ and each one of shape elements π_i(i=2, 3, 4) were expressed as: π_1h=f_h(π₂, π₃, π₄, …, π₈) =f_h=(π₂), similarly π_1b=f_b(π₃), π_1b′=f_b′(π₃), and π_1λ=f_λ (π₄) in which term π_i′s are the variables required to hold constant and constitute the establishing conditions of the component equations.
3. Each component equation was determined by the experiments. The test results showed that the influences of each one of shape elements on π₁ were unexpectedly large. Then, it was concluded that the stress concentration on the grousers would be the reason of arising the influence, considering the unusual soil deformation observed remarkably in the tests of certain shapes of annuli, such as the soil compaction in the direction of grouser movement and the flow of a part of the soil adjacent to grousers out from the annulus peripheral. And, in these cases, the term π₁′s obtained were relatively small. Then we concluded that the peak value with the change of shape element expressed relatively right value of the soil shear stress.
4. The new fact that the term π₁′ increases with the increase of the shape element π₃ was revealed theoretically, considering the influence of the frictional speed on the soil sheraing stress. The experimental value coincided well with the theoretical value.
5 A standard annulus which measures right soil-shearing stress was required to establish. Then, the annulus whose shape was determined by each shape element which measured peak π₁ value was recommended as the standard annulus.

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A computer controlled automatic vibratory tillage test equipment which attains the minimum draft and power has been developed. Three modes of the control program were made and tested with this equipment. A computer simulation to investigate the control performances of the above modes was carried out. The main results are summarized as follows.
1) All of the three control modes converged to the same steady state when the velocity ratio was kept constant.
2) The control mode in which the blade frequency was the twice of the shearing frequency (frequency control mode) showed the optimum control with the minimum draft and power. The velocity of the convergence was also the greatest of the three.
3) From the results of the simulations the frequency control mode achieved the best control performance. The fluctuations of the draft reduction ratio was less than 10% under various cutting depth and soil moisture.

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The edged curve angle (α) between the radius direction of the turning blade and a tangential line of its edged curve, is the most important parameter to design the knife-edged curve of Japanese rotary blades. The authors prepared such various lengthwise blades as shown in Fig. 4. The edged curve applied to those blades was Archimedes' Spiral of selected values of angle α, which were 30°, 40°, 50°, 55°, 60° and 70°. An entwining phenomenon of a straw or a grass on a rotary tillage axle is not influenced only by this edged curve angle but also by the cultivating conditions.
In this paper, the table of orthogonal arrays L₁₆ type was used to analyze the above problems. The results were that, a significant at 99% or 95% level on the entwining phenomenon of straw was found in all factors without the factor of tillage depth (H). The highest coefficient of determination at the factor of edged curve angle was obtained. The percentage of entwining straw on rotary axle decreases as the edged curve angle increases, especially the entwining phenomenon of straw could not arise when the edged curve angle was bigger than 55°.
According to the characteristics of soil cutting resistance and the entwining phenomenon of straw or grass, the range of the edged curve angle of 55° to 60° should be used for design of knife-edged curve in the case of Japanese rotary blades.

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A compact analytical expression was obtained for aeration cooling of deep bed of high moisture rough rice, after extention of Schumann's theory to the case of heat and mass transfer.
The equations obtained in this paper (Eqs. (10), (11)) are based on the following new assumptions. (1) The heat rate transferred between grain particles and air is proportional to difference between enthalpy of saturation steam at grain temperature and air enthalpy. (2) The relation between enthalpy and temperature for a saturated condition is approximated by a linear function. (3) The increase of air enthalpy is equal to the decrease of sensible heat of grain particles. These equations formally correspond to Schumann's equations, and so, it is convenient to apply the analyticall solution and the calculated chart.
The calculated results were in satisfactory agreement with the experimental values. And the availability of this analytical method was confirmed.

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In order to clear the compression characteristic of the rice husk, the simple compression test, the gradational compression test and the repeated compression test were experimented using the plunger and cylinder type compression device. The physical characteristics of the rice husk were investigated before these tests. The average value of the specific gravity was 1.37-1.45, particle size distribution was rather uniform and the half of husk ranged between 2mm to 2.4mm. The value of the angle of the static repose was 51.4°, the angle of the dynamic repose was 46.3°, the angle of the internal friction was 34.2°, the cohesive force was 0.07kgf/cm² {6.7kPa} and the coefficient of friction between the steel plate was 0.23.
Compression characteristics of rice husks are summarized as follows.
1) The following equation on the relation between the compression stress and the compression strain was obtained from the simple compression test.
P=α·exp β·ε
where, P is the compression force kgf/cm² {kPa}, ε is the compression strain and α, β are constant values.
2) The relation between the compression force and the compression strain on the stage compression test was similar as the behavior on the simple compression test.
3) When the rice husk was compressed by the repeated constant force, the strain increased with increase of the number of compression. The compression strain had a tendency to reach the maximum value after about 10 times of repeated compression. and also the restoration ratio decreased with increase of the number of compression.
4) When the husk was compressed by the repeated constant stroke compression, the compression force decreased with the increase of the number of compression. The compression force had a tendency to reach the constant value after about 10 times of the repeated compression.
5) When the new husk was supplied in the space of the cylinder under the repeated constant stroke compression, the longer the compression stroke of plunger, the more the supplied new husk and the larger the compression force.

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It has been reported in the preceeding paper that temperature was the only factor that affected banana ripening with ethylene which was estimated by sugar content of pulp. In order to control sugar content by temperature during artificial banana ripening, it was tried in this study to relate sugar content indirectly to ripening temperature through other factors.
The obtained results were summarized below.
1) Evolution rate of banana during ripening with ethylene was observed at different constant temperatures and shown in Fig. 4. Significant differences in evolution rate were seen between temperatures.
2) Change in evolution rate was predictable when ripening temperature was lowered within the variation of 2.5°C.
3) It was found that sugar content was closely correlated to the quantity of evolved CO₂ by banana, and the graph is shown in Fig. 9. This makes it possible to predict sugar content with good accuracy by knowing the quantity of evolved CO₂ during banana ripening.
4) In banana ripening without ethylene, the increase of sugar content up to 4500mg/kg of CO₂ evolution was less than that in ripening with ethylene while it was identical in ripening both with and without ethylene over 4500mg/kg of CO₂ evolution (Fig. 10). The value of 4500mg/kg could be used as the criterion for the end of storage of bananas.

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Measuring the state of cooked cocoons by impulse response method was experimented.
Some of the experimental results were as follows:
1. With the progress of cooking of cocoons the impulse response waveforms of cocoons which were shown in damping curve (Fig. 4) showed the tendency of higher values of the first peak Xh, and also this progress resulted in higher value of the logarithmic decrement δ, larger difference of h between the original level and convergence level, and lower value of the frequency f.
2. The method which developed the cooking state of cocoons was discussed.
As a result, in this method the Xh values of impulse response waveforms indicated the cooking states of cocoons such as Under cooking, Mediumm cooking and Over cooking (Fig. 7).
In case that the distance between the original level and convergence level of the impulse response waveform (h) was observed and the logarithmic decrement δ was in the value of 0.37-0.38, the cocoons were found to be in a well cooked condition.
3. The state of cooked cocoons was measured instantaneously and estimated by this method.
Therefore this method can be applied for the estimation of cocoons state instead of the cocoon cooking-technician in silk production process.

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The temperatures of atmosphere and radial centers of several important vegetables in the field were measured without stopping in the winter of 1978-1979.
The degree of feezing damage was investigated in consideration of apparent modulus of elasticity and sensory evaluation as well as the change in temperature of them. This work was done to make the fundamental data applicable to energy saving for the storage of farm products.
The results may be summarized as follows:
1. Relation between the minimum temperatures of atmosphere and roots was explained by a straight line with refraction of mid-November and early in December for radishes·carrots and Chinese yams, respectively (Fig. 1).
2. It is considered that the freezing of soil and roots caused the refraction.
3. Mean of temperature fluctuation of a day was about 1 and 7°C for root and leafy vegetables, respectively (Fig. 2).
4. Because of the small cooling rates of root (0.1) and leafy (0.5°C/h), it is inferred that their freezing rates should be very slow (Table 2).
5. The freezing damage to vegetables accompanied the drops both of apparent modulus of elasticity and residual moisture content (Fig. s 3 to 8).
6. And almost the constant residual moisture content of carrots suggests the freezing damage to carrots is especially very slight (Fig. 7).
7. Water holding capacity after cooking of vegetables indicates a degree in freezing damage (Table 4).
8. At Obihiro in general, radishes·Chinese cabbage, cabbage, carrots, and Chinese yam·edible burdock will be stored in the field with the roots at the earliest up to November 24, November 28, December 6 and throughout a winter, respectively.
9. The field storage time for carrots will be extended far by raising furrow of them with soil in the autumn, while for a little injured cabbage by improving its cooking method.

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As it was noticed in the previous part that the weight/statue of tractor drivers gives a remarkable effect on ride data, this effect was argued from the mechanical impedance of human body in the sitting posture. Mechanical impedance of 10 male subjects was measured in erect and relaxed posture, and ergometric data of the subjects were also obtained. From the impedance data of every subject the parameters of a human model of 2 degrees of freedom were inferred. Further, three impedance curves with their model parameters were proposed, which correspond to big, medium, and small Japanese male respectively.

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