To investigate the transmissive characteristics of vibrations between tractor seat and tractor body, several outdoor experiments were done successively. The rubber materials are served as the vibration absorbing materials. Two strain-gage-type accelerometers were firmly attached to the tractor seat and the tractor body respectively. The vertical accelerations for the tractor body and seat were analyzed in terms of power spectral density (PSD) analysis quantitatively and the following findings were obtained.
1) PSD analysis exhibits that the only frequency component excited by the engine vibration could strongly affect the tractor body acceleration during running in the field which has been tilled by the rotary tiller beforehand, On the contrary, the inherent frequency component for the tractor seat acceleration, that is 2f₀, might be seen as the lower intensity component due to filter action of the vibration absorbing materials.
2) The tractor operator is perceptible of the frequency component occurred by the gravel road profile for the higher travel speed region arid hence it can deductively be pointed out to lessen the ride comfort with reference to human's natural frequency.
3) It could be discerned that slight effects for the contained frequency component were brought by power transmission system, i. e. gear backlash, un-balanced mass motion and so forth. But it is of significance to note the little effect of tire lugs.
4) The frequency response function |H(f)| shows 1 to 1.2 for the mean value and 7.8 for the peak point respectively. It can be observed that the overall tendencies of transfer function for the tractor and seat system are clear by the frequency response function.

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In this paper, the slip sinkage phenomenon of tractor drive wheel was simulated by the logistic curve expressed by the equation (16) and the data obtained from the experiments were compared with the computed results.
The application of that logistic curve to the slip sinkage transient phenomenon of tractor drive wheel at running was quite valid.
In the measurement of the contact pressure of the wheel tread, a small piece of iron beam was used by knowing the deflection of that beam during the rotation of the tested wheel.
The three point moving average method was used to smooth the recorded curve of the slip sinkage of the drive wheel and the curve arranged by that method was drawn by the use of XY plotter under the control of computer.
The following items were obtained through the experiments:
1) Slippage, s has approximately a linear relation to the potential sinkage, h_o. correlation factor between them was 0.67.
The equation expressing the relation between them was
h₀=0.534s-0.465…(33)
2) The maximum contact pressure of the wheel decreases when the total sinkage, h_t increases.
3) The contact angle and the contact length were almost constant in spite of an increase of the sinkage of the wheel.
4) The constant, K₀ decreases with the increase of the sinkage of the wheel.

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Settlement speed of travelling vehicles is more speedy than the routine test of plate penetration to know the tracka of vehicles, and the effects of penetration speed on penetration depth-resistance curves must be taken in to account.
In this paper, the influences of settlement speed of vehicles on the track were studied. The conclusions were as follows.
The expression (4) was postulated to calculate the track of travelling vehicles. Calculated value from (4) gives more approximate value to measured value than the value gained by substituting coefficients from routine test in to expression (4).
Furthermore, many penetration tests on various soil must be carried out to know the value ‘m’ which is the coefficient to express the influence of penetration speed on the track of vehicles.

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The test crops and the test conditions of the rotary tiller were the same as those of part III.
The result was as follows;
(1) The field tilled after wheat has more stalks than the field tilled after paddy.
(2) When the size of the increment of cut was small, the performance of cutting and covering of stubbles was good. That was clear in the field after italian rye grass, and that was not clear so much in the field after wheat and rapeseed.
(3) The performance of cutting and covering of stubbles of 32 tines was better than that of 16 tines, in the same increment of cut of each crop.
(4) The performance of cutting and covering of stubbles in tilling depth of 10cm was better than in tilling depth of 5cm, in the same increment of cut.
(5) The performance of cutting and covering of stubbles in double tilling was a little better than that in one tilling, except rapeseed; and there was little difference between every test sections.
(6) Total remaining ratio in the fields after wheat and paddy was a little smaller than that in the field after italian rye grass and weedy paddy field.
(7) Tilling accuracy in uncovered field and the field after wheat and rapeseed was better than that in the fields after italian rye grass and weedy paddy field, The class of tilling accuracy of the former was more than B′ and those of the latter was C′-E′. The class of the smallest increment of cut [Hm 0.2], was more than A′, in every crop.
(8) When the tilling accuracy was better, the staying stubbles at tines were less, in the weeder for walking tractor.

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In search for the design principle of high speed Japanese plows, the author tried to develop the formulae to convert a conventional Japanese plow shape into high speed one with the assumption of the equal acceleration of furrow slice sidewards as well as upwards.
Then a high speed Japanese plow shape was calculated and constructed. Field tests on the turning performance of furrow slice and on the resistance were carried out.
The main results are the followings.
1) Using the formulas of the relationship between the moldboard shape and the path of furrow slice as well as the assumption of equal acceleration, the formulae (27), (28) and (29) for the conversion of a conventional low speed Japanese plow shape into high speed one were introduced.
2) Calculating the profile lines of the high speed Japanese plow with above equations, a moldboard shape for high speed was constructed.
3) The developed high speed Japanese plow shape was smoother and with less change of profile slope in α and β lines. The γ lines had, however, the opposite characteristics.
4) The results of the field tests showed that the developed high speed Japanese plow had just so good turning performance of furrow slice as conventional low speed Japanese plow.
5) The resistance force to the high speed Japanese plow was, however, considerably larger than that of the conventional low speed one. The reduction of the resistance must be achieved in the future.

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No descriptions have been made about the methods of manufacturing artificial soils in most of the reports concerning with them.
In the preceding tests with artificial soils, the authors noticed that the touch of them was changing while we mixed and stirred a mixture of sand, bentonite and oil in a vessel with hands and that kneading effects would occur in an artificial soil as well as in natural soils by machanical manipulations, We thought that in ordinary soil bin tests, it would be better to use artificial soils beyond their “saturation point of kneading effect”, that is to say, artificial soils should be kneaded to such an extent that no further effects occur. That was the aim of this study.
A certain strength of an artificial soil can be expressed in equation (1). Cone and plate penetration resistances were selected as Q. Temperature was controlled within 24±2°C. The kneading action given to the mixtures examined in this test covered broad ranges when compared with soil mixing action given in ordinary soil bin tests.
The following conclusions obtained by this small scale test, in which rather a simple soil preparation method was adopted, suggest the necessity of reinvestigation in the preparation processes in usual soil bin tests at the use of artificial soils
1) Three kinds artificial soils were manufactured consisting of mould sand, bentonite and cylinder oil 90W. At first, equal quantities of sand and bentonite were mixed in the stirring vessel and after a minute, oil was added, namely, soil A; 9.91%, soil B; 16.12% and soil C; 20.00% in weight ratio. The grades of kneading time were determined by the observation of the test materials while they were being kneaded and are shown in Table 1.
2) Kneading effects and saturation points were recognized in two kinds of the test artificial soils (Figure g), Penetration resistances decreased (soil A) or increased (soil B) as the soils were kneaded and reached a constant value respectively within about 20 minutes, But, a steady tendency was not obtained in soil C.
3) A reproducibility of the artificial soil was examined (Table 2), The reproducibility at the surface layer was inferior to those of deeper zones. Though the numbers of repetition of tests were small, we dare to make a statement that in a similitude studies or studies on dynamic behaviours of soil machine system dealing with several percentages of differences of forces, elaborate soil preparing techniques will be necessary before tests. The problems concerning with soil preparation remain particularly in soil C as well as in natural cohesive soils.
4) Sufficient strength was found in the artificial soils to simulate natural soils covering from sandy barns to cohesive clay concerning with cone index.

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In this paper, the relationship between the properties of sheaf bound by a tested binder (One raw type) and the straw compression pressures acted on clutch door was investigated by the use of canonical correlation analysis.
It was the purpose of this analysis to check the outline of discussion for three previous papers (II-IV).
Results of analysis were as follows.
(1) The correlation matrices for several correlated random variables (Fig. 1) with a number of individually sampled sheaf were calculated and discussed (Table 1-4).
(2) The selections and transformations of variables to express the tightness of bound sheaf by the specific value Pi were studied by basing upon reducing the first canonical correlation coefficients (Table 5-8).
(3) The changes of components of structure vector and normal weight vector of the first canonical composite variable for straw compression pressures PFΘ were studied to understand with the binding action timing of tested binder. The structures of this first canonical composite variable make it clear with correlations that the tightness of bound sheaf have close connection to the binding mechanism of binder and its action timing (Fig. 3, 4 and 6).
(4) Mean values of Pi make it clear quantitatively that the reducing of tightness of bound sheaf is most directly effected upon the water contents of sheaf and the size of sheaf under the condition of natural indoor drying (Fig. 2).
(5) Under this condition, the predict equations (1) of the first canonical composite variable U for the tightness of bound sheaf Pi (kg/cm²) and V for the straw compression pressures PFΘ (kg/cm²) were introdused. Composite values U and V for every sampled sheaf were calculated by those equations (Table 9 and Fig. 5).

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Automatic operation of the car for exclusive use of transport becomes a useful method for the reduction of labor in vinyl house.
The author produced two types of automatic operation devices, the trolley car and the battery car. The results of performance test were as follows:
(1) The purposes of automatic operation are automatic starting and automatic stopping of the car. Workers recognize the car stop by the buzzer, and load the harvests on the car or unload the harveste from the car.
(2) The trolley car was equipped with D. C. motor (12V, 144W) for the prime mover. It could be loaded with 50kg (the standard load) and had about 0.35m/s travel speed.
The car equipped with a driving wheel and four supporting wheels, and the driving wheel ran in the guide rail.
(3) The automatic operation device of the trolley car was set between the trolley duct and the rectifier that was the source of electricity. The sauce of electricity of the time switch used in the device was A. C. 100V.
Performace of reset of the time switch was inaccurate when set above 80 second.
(4) The structure of the battery car was the same as the trolley car, but output of the motor equipped was 192W and the capacity of the battery used was 60AH.
Inputs of the motor were 145W and 150W when loaded 0kg and 105kg respectively. Therefore input were independent of the load.
(5) The electric time reley circuit that applied the unijunction transistor and the thyristor war used in the automatic operation device of the battery car. The stoppage time could be varied from 30 second to 150 second by changing the resistance of the circuit from 15kΩ to 85kΩ by 8 stepes.
Sufficient results were obtained for the performance of the time reley by the experiment.
(6) Times of the continuous automatic operation of the battery car were 3 hours when it was loaded 45kg, and the value of its application was recognized.

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The authors studied on the characteristics of of moisture transfer of the dehydration process of some agriculutural products such as vegetables and grass which contained much moisture.
1) In the case of drying agricultural products like vegetables and grass which had comparatively high moisture content, and their drying characteristics having the period of constant drying rate, the relationship among initial moisture content (M_i, %d. b.), first critical moist. cant. (M_f1, %d. b.) and absolute temp. of drying air (T, °K) was expressed as follows;
I-M_f1/M_i=A·exp(B·T) where, A, B=constants.
2) Though definite functional relationship between second critical moisture content (M_f2, %d. b.) and T was not shown, the following ranges of M_f2 were obtained.
KANPYO 16-20
carrot 12.5-20 (G=341-471)
carrot 11-46 (G=1310-1640)
Onion 11-17
spinage (raw) 3-7
spinage (blanched) 2-49
italian rye grass 6-8
horse radish 10-16 where, G=mass flow rate of drying air per dry matter (kg/h·kg-d. m.)
3) Equilibrium moisture content (M_E) on drying agricultural products which had much moist. cont. was substituted for M_E in the equation of Henderson (I-r. h.=exp(-a·T·M_Eⁿ), the constants such as a and n of every agricultural products experimented on were as follows;
4) The equation expressing the relationship between the heat transfer coefficient of film (h_c, kcal/m²·h·c) on the drying material and mass flow rate per drying air per dry matter (G) was as follows;
h_c=C·G^d where, C, D=constants.
5) The relationship between the first falling rate of drying constant K₁ of each agricultural product experimented on and the absolute temp. of drying air was shown in the equation of Arrhenius (K₁=E·exp(f/T)), where E. f were as follows;
6) There were three kinds of characteristics in the relationship between the second falling rate of drying constant K₂ and absolute temp. of drying air T.
(1) The first group of agricultural products experimented on such as onions, spinage (blanched) and Italian rye grass which had thin leaves showed positive relationship between K₂ and T.
(2) The second group included carrots, KANPYO, spinage (raw) and other which had thick leaves and their plant organizations were not mollified. This group showed negative relationship between K₂ and T.
(3) The last group such as horse radish which contained volatile materials, had K₂ as constant on T.
7) In the case of these agricultural products experimented on except horseradish, the relationship between the moisture decreasing ratio (1-M/M_i) and the volume decreasing ratio (1-V/V_i) was about 1:1 in the period of constant drying rate. The relationship became 1-M/M_i>1-V/V_i due to the period of first falling rate drying, and then, the shrinkage phenomena stopped when the moist. cont. reached near the second critical moist. cont. M_f2.

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About 40tons of rough rice containing, on the average, 14.5% moisture was stored in each of two storage bins of steel plate (1.6mm thickness) in a dry-store (Satake air sweep flow system, Cap. 500tons) for a period of about 8.5 months from November 26, 1972 to August 7, 1973.
During this period, the grain temperature and the moisture content, which might be the main factors affecting the qualities of rice, were measured, and the changes in quality of the rough rice were examined at monthly intervals.
The results obtained are summarized as follows:
(1) At the biginning of storage in November, the grain temperature was uniformly kept at about 10°C, in the whole depth of the bins. It gradually dropped under the influence of the colder open air in the winter, and attained to the minimum of 4°C. in the middle of February and remained at this level until the end of March.
(2) Thereafter, The grain temperature near the wall and the upper surface rose steadily, being about 5 to 12°C, higher than in the lower and central parts of the bin from the middle of April to the middle of June.
(3) From the middle of July in the last stage of storage, the temperatures inside the air duct and the plenum chamber rose under the influence of the ambient temperature much higher than in the inner part of the bin. As a result, the grain temperature rose rapidly to about 25°C. in the lower and central parts, and the differences in temperature among different parts decreased about 3 to 5°C.
(4) The grain moisture content was kept on the average at 14.5% throughout the whole period of storage, and the rate of germination showed values higher than 95% even at the end of storage, on August 6. The fat acidity values also remained at a low value of 11mg KOH/100g dry matter.
(5) The grain temperature just inside the wall facing southeast and exposed to the direct sun shine rose above 30°C, and exceeded 40°C, several times during the hot period in July. In such a case, the moisture content of the grain was reduced to about 1%, but the rates of germination and crack did not differ from those in the central part of the bin. Also, the fat acidity values remained at 11mg KOH/100g dry matter.
(6) A shelter plate standing outside the bin was effective on falling the temperature of the inside wall but not on the quality of rice which was not deteriorated by the summer heat. The bin was therefore capable of maintaining the qualities of the grain in good conditions even in the hot summer without the shelter plate.

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Vacuum picking up of grain is significantly efficient for high precisely seed metering or grain separating. Picking up of a spherical particle was theoretically analyzed and the experiments of vacuum picking up of several grains were conducted, and then the conclusions were obtained as follows:
1) The theoretical equation of vacuum picking up of a spherical particle assuming that air flow is irrotational, was consistent with the results of experiment using foam polystyrene ball. (Fig. 4 and 5)
2) Picking up ratio of unhulled rice was 100% when hole diameter was 2mm, distance between hole and grain was 0mm and vacuum pressure was 100mm Aq. Decreasing vacuum pressure P, remaining ratio of grain was 50% when P was twice of theoretical holding pressure 8mmAq, and 0% when P became zero. (Fig. 7 and 14)
3) Picking up ratio of soy bean was 100% when hole diameter was 3mm, distance was 0mm and vacuum pressure was 150mm Aq. Decreasing P, soy beans were removing when P was smaller than theoretical holding pressure 30mmAq. (Fig. g and 14)
4) Picking up ratio of rapeseed was 100% when hole diameter was 1mm, distance was 0mm and P was about 50mmAq. Decreasing P, remaining ratio was 50% when P was twice of theoretical holding pressure 4mmAq, and 0% when P became zero. (Fig. 11 and 14)
5) Picking up ratio of unhulled rice with awn was lower than unhulled rice without awn, and remaining ratio was 30% when P was zero. (Fig. 11 and 14)
6) After multiple regression analyzing of picking up ratio (η) using vecuum pressure (P), hole diameter (R) and distance (D) as inependent variables, the experimental equations were obtained for each grain.
7) Suggestions for future research are vacuum picking up using holes on rotational roll and picking up with positive air pressure, etc.

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