In this paper, the discussions on the slip- draft control of tractor for farm use were held.
Simulation technique was applied in constructing the bench test facility for simulating the tractor behavior at drawing operations.
In Fig. 1. the constructed bench test facility is shown.
Farm tractor generally has a three point linkage hitch system which can be hydraulically controlled detecting the spring displacement to know the compressing force acting on the top link.
In this research work, two generator tachometers were used instead of the load sensing spring to detect the slippage of the drive wheel. Two input signals (voltages) from two generators were electronically compared and amplified, then the hydraulic circuit was controlled under the on-off motion of relay and solenoid valve in keeping the constant slippage and constant traction force.
Operations and control were kept quite well. The theoretical and experimental discussions will be held in the future report.

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In preceding report of this series, it was recognized that the value of side-force calculated with he theoretical equation, obtained by developing the theory of E. Fiala, agreed well with the experimental results on rolling wheel.
In this paper, the applicability of this theoretical equation was discussed based on the results obtained by the experiment on driving wheel, using both smooth and agricultural tire
Main results were as follows:
1. The hydothesis that the value of side force calculated with the equation was equal to the experimental value, was acceptable at a level of 0.01 by the chisquare criterion. The mean percentage error of experimental values was within 5 percent at each side slip angle. From these results, it was clearly recognized that the side force of driving wheel was calculated rightly with the equation.
2. The value of C that was a factor of cornering coefficient, obtained by the method of least squars, became very small with the increase of tractive force for smooth tire, but there was no very much change for agricultural tire. From these results, agricultural tire was more useful than smooth tire, though the running stability for side slipping was worse in comparison with smooth tire at small traction force.
3. The coefficient of lateral dynamic friction became slightly small with the increase of traction force for smooth tire, but conversely large for agricultural tire owing to the increase of lug deflection.
4. The dynamic frictional resistance of both smooth and agricultural tire was indicated by the half of the diamenter of elliptical shape.

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Investigating various equations which represent shear stress-displacement curves, the author found that the Kacigin-Guskov equation as follows should apply to only a limited case where f_s=2, 7554 f_m
τ/p=f_m(1+a/cosh(d/K_τ))tanh(d/K_τ)
a=2.55(f_s-f_m/f_m)^0.825
Instead of Kacigin-Guskov equation the author proposed a corrected equation depend on Pokrovski equation, that is:
τ/p=f_m×[1-√1-f_m/f_se^{d/K_τlog{1+f_s/f_m(√1-f_m/f_s-1)}}/√1-f_m/f_s(1-2f_s/f_m)+2f_s/f_m-2]×[1-e^{d/K_τlog{1+f_s/f_m(√1-f_m/f_s-1)}}]
Furthermore, the author compared both formulae by figures which were made by a XY plotter and confirmed the usefulness of the corrected equation.

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Ellipsoidal or spindle-like seeds, such as the ones of grass or grain, flying in the air after being launched out at the high speed of 10-40m/s from a spinner of a centrifugal distibutor, differ in distribution from what happens in the case of spheres.
It is observed in the former that some fall down near at our feet and some considerably far from us.
The purpose of this paper is to report the flying distance and the width of distribution of those particles, which were observed by the high speed camera that caught their flying aspects, and in the experiment by means of wind-tunnel that indicated how different were those coefficients of air-resistance by direction.
1. The particles which are launched from the blade are not provided with any force of rotating motion. However, their rotation movment sometimes occurs through the balance of air-resistance on their flight.
2. The general flight of seed particles is 30°-70° in the positive or negative angle against the horizontal. However, they cannot keep flying long in the same condition. They change their flying conditions, from one stable condition to another.
3. When the particles whose shape is almost spheroidal, start flying at a slow speed, they are subject to the law of free falling. However, the particles in other case are not subject to the law. Since their lift becomes positive or negative in accordance with their flying orientation, the velocity of their falling is so much indefinite.
4. The surface coefficients of air resistance in the three directions of X, Y and Z are C_x≥C_y≥_zC in all studied ellipsoidal seed particles within R_e>10³. One relative formula will be found by arranging the results of those seed particles on the basis of the sphericity φ.
5. The lift of an oat seed will come to zero, when its attack angle α comes to the approximate-10° and is prone to increase more rapidly in positive of α than in negative. Its maximum value will come at α≈50. The lift for the Sphericity φ will come to its maximum at φ≈0, 3 and will be decreased rectilinearly when φ is coming near 1.
6. If the weight and initial velocity and length of the three axes of the particles which are launched should predict their flying distance and the width of their distribution, it will be very convenient to us.
The average of flying distance where the density becomes thickest is follows:
l≈1/2K₁[l_n(2K₃V_x0²/g+1)+l_n(1.5K₁V_x0/g+K₃V_x0²)^1/2+1)]
The width of distribution in X-direction will be able to be known by the following semi-experimental formula:
D_x≈1/K₁[l_n(2K₃V_x0²/g+1)-l_n(1.5K₁V_x0/(g+K₃V_x0²)^1/2+1)]+3.5×10^-3γ
In this case, it should be taken Into consideration that their distributing width will be increased through the vector of Y-direction by ther jumping on the spinner.
K₁=Sγ_lC_x/2w
K₃=Sγ_lC_l/2w
v_x0=Initial velocity for x-direction [m/s]
g=Acceleration of gravity [m/s²]
S=surface area of particle [m²]
w=Weight of particle [kg]
γ_l=Specific weight of eir [kg/m³]
γ=Specific weight of particle [kg/m³]

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In the exponential model proposed by Henderson (eq. (1)), the parameter M_e is simply obtained from eq. (5). There existed no such method for Sphere Drying Model (eq. (2)). The author proposed a simple method to calculate the parameters M_e and K of the sphere drying model, defining a function φ_1/n(X) expressed in eq. (6).
The calculation procedure is as follows:
(1) Choose the time t₁ and t₂, where t₂=nt₁, and measure the moisture content M₁ and M₂ at time t₁ and t₂ respectively.
(2) Calculate the value φ*=M₀-M₂/M₀-M₁
(3) Find the value X which satisfies φ_1/n(X)=φ* from the φ_1/n(X) and Φ(X) table, a part of which is shown in Tab. 1.
(4) Find the value of Φ(X) for the X determined above.
(5) The value of parameter K is given by K=X/t₂
(6) M_e is given by M_e=M₂-M₀Φ(X)/1-Φ(X).
This method was applied to the experimental data of grain drying and showed a remarkable stability with calculated parameters, especially for drying data of beans.
The author also computed ξ and μ the relative and normalized deviations of calculated values of K and M_e from “true” values, if the measured moisture contents M₁ and M₂ deviated from “true” values described with ε₁ and ε₂ in eq. (14), where “true” means “of the model with the most suitable parameters for the experimental data determined by e. g. least square method”. As an example, ξ and μ values with ε₁=±0.01, ε₂=-ε₁, are shown in Fig. 3 and Fig. 4.
The partial derivatives of ξ and μ with respect to ε₁ and ε₂ at ε₁=ε₂=0, which represent the contribution of ε₁ and ε₂ to ξ and μ, are shown in Fig. 5 and Fig. 6. Considering the results of Fig. 3-Fig. 6, the following points must be noticed if the deviations ξ and μ are to be small.
i) Both ξ and μ become smaller with greater n.
ii) ξ has a minimum within the non-dimensional time X=3-6, while μ is expected to decrease as X increases.

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In order to make up a model of drying and sorption of grain under changing conditions, we identified the moisture transfer models of unhulled rice and hulled rice of a single layer under constant air temperature. In the frequency characteristics of moisture transfer, we compared the experimental results with the calculated results of various kinds of assumed drying models.
1. Because the characteristic which exists between relative humidity and moisture content is nonlinear, we separated the model into two parts; the static characteristic (equilibrium moisture content curve) and the linear component depending on frequency as shown in Fig. 2. In the latter component, we considered the equilibrium moisture content of air as input and the average moistent content of grain as output, and the frequency response between them was observed with the experimental devices shown in Fig. 4.
2. The output waves observed in these experiments were described in Figs. 5, 6, and the frequency characteristics appearing in Figs. 8, 9, 10, were obtained by arranging these results versus each frequency.
3. We calculated the frequency characteristics of the various kinds of models, and compared them with the experimental results. In the spherical model without film resistance, the calculated values agreed with the gain characteristic of the experimental values except the phase shift characteristic. In the spherical model with film resistance of moisture transfer based on two-film theory, the calculated values agreed with both gain and phase shift of the experimental values.
4. From the practical point of view, moreover, a simple lumped model was recommended, and it was revealed that an agreement between the experimental and theoretical results in both gain and phase shift was obtained even in the lumped model with reasonadle parameters.

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Drying and Storage plants (“In Bin” Drying System) have been developed and spread in Europe and America. Originally, Drying and Storage refers to the drying of paddy in the same bin in which it is to be stored. Drying usually can be accomplished with unheated air, but heating equipment might be available as an insurance for periods of high humidity weather. Squaral or round type of galvanised steel bins are installed at these plants.
In Japan, the squaral bin type plant which was imported in 1966 to the TOKACHI Agricultural Experiment Station in Hokkaido was the first plant and its commercial name was DRYSTORE.
Afterwards similar facilities were attached to some other Rice-center plants and they are now accepted as efficient means of storage and drying, and their use is spreading in Japan.
The drying and storage plant consists of the bottom ventilation system of stored grain for drying and conditioning and the mechanical handling system including airsweep floors for bin self-emptying. Generally, the drying and storage plant has many uses such as a dryer, a bulk storage bin, a temporary storage bin (a holding tank of undried paddy) and a tempering tank during drying process.
Since the end of 1971, the authors have been investigating on effective operation of the drying and storage plant (so called DRYSTORE) attached to the Country Elevator of MUKAWA Agricultural Cooperative Association in Hokkaido, that was built for the first time in Japan. This plant is installed with 40 squaral steel bins of about 90m³ (length: 5.14m, width: 3.13m, depth: 5.6m) or 55 tons capacity of dried paddy (Fig. 1).
This report is on a series of fundamental investigations conducted to determine the drying characteristics of paddy, using this plant as a drying facility with supplemental heated air (less than 30°C). The results obtained are as follows.
The drying rate reduced with increase of the thickness of paddy and increased with increase of airflow rate in both 1 bin and 3-4 bins drying tests. But when the airflow rate exceeded certain values, the increase of drying rate became smaller and it reached a fixed value (about 0.7%/hr) at 2m³/(sec. ton) airflow rate (Fig. 8).
From the viewpoints of uniformity of moisture contents and thermal and economical efficiency, the maximum depth recommended for bin drying of paddy was 2 meters when 1 bin was used as a dryer.
Whenever bins are available for drying, several bins should be used as a dryer for the efficient use of bins. And the paddy should not be piled over 1 meter depth in each bin.
When large difference of moisture content is observed between top and bottom layer samples, it may be advisable to move paddy from bin to move paddy from bin to another in order to eliminate thie moisture difference.

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In wire type sugarcane stripping machine, we analyzed theoretically the deflection of wire, the force acting at the top of wire and the stress at the root of wire during the process of stripping cane leaves.
In order to confirm the theory experimentally, we put octagonal ring for force transducer on the place where was at equal distance from upper and lower stripping drums of wire type sugarcane stripping machine. When the stripping drum was rotated slowly, we measured the normal and horizontal forces acting at the top of wire rubbing the plate on octagonal ring.
The results obtained were as follows.
(1) The normal force acting at the top of wire was larger than the horizontal force.
(2) The force acting at the top of wire was the smallest at the initial place where wire came in touch with sugarcane and was the largest at the place where wire separated from sugarcane, obtaining close agreement between the tendency of experimental values and calculated values.
(3) If wire was fixed on stripping drum, the stress at the root of wire increased as the length of lap increased. If the length of lap was longer than 25mm, the stress at the root of wire was larger than the fatigue limit of piano wire.

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In this paper we describe an experimental study of the comparative effects of precooling and storage methods on the quality of satsuma Mandarin and the storage parformance of jacketed cold storage.
The quality of Satsuma Mandarin was inspected for external appearance, weight loss, sugar content and acidity during storage.
A summary of the results is shown below.
1) The rate of weight loss of Satsuma Mandarin which cured, hydrocooled, packed in mesh container and room-cooled and packed in paper carton and room-cooled and stored in conventional cold storage (3±1.5°C, 85±5% R. H.) was 7.06, 6.29, 6.50, 5.86% a month, and stored in jacketed cold storage (3±1.0°C, 92.5±2.5% R. H.) was 6.08, 5.29, 5.57, 5.61% a month respectively.
2) The accumulated weight of decayed Satsuma Mandarin in jacketed cold storage was about half of that of conventional cold storage.
3) Curing treatment had some effect on the quality of Satsuma Mandarin stored at normal temperature after cured, but had no effect on that stored in cold storage.
4) The coefficient of correlation between sugar content, acidity and storage time of Satsuma Mandarin was +0.58 and -0.88 respectively.
5) From the view point of deteroration of the acidity, as a tentative criterion, commericial storage limits of Satsuma Mandarin in conventional and jacketed cold storbge was mid April and mid May respectively.
6) From the facts described above, we may conclude that jacketed cold storage has a superior storage performance than that of conventional cold storage for Satsuma Mandarin.

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In order to store wafers compressed at high moisture content, it is necessary to clear the drying characteristics of wafer in relation to its density and cutting length. Because the rolled compressed wafers whose moisture contents range from 40% to 60% can provide the best moisture content range for haylaging, an experiment regarding haylaging of rolled compressed wafers was carried out, with wafers hermetically stored and packaged in plastic film tubes and obtained the following results.
1) The relation of moisture content to drying time for wafer density and cutting length gave a straight line when it was plotted on semilogarithmic paper. Some differences of drying rate in the results arised from wafer density and cutting length, but the drying rate was very slow.
2) The difference in moisture distribution of dried wafers was larger along the axial direction than along the radial direction, and the moisture contents of dried wafers decreased roughly along the radial direction and straightly along the axial direction.
3) The expansion of plastic film tubes by water-vapor and CO₂ generated from the hermetic storage wafers arised at the moisture content above 49%, and not under 43% regardless of wafer density and exhaust of air from packaged wafers.
4) The generation of mold during hermetic storage depended on the physical properties of plastic films. The plastic films are to have air tightness and resistance to mechanical shocks during transportation and handling.
5) The lactic acid fermentation during hermetic storage occurred vigorously with the increase of wafer density and moisture content of wafers, but the estimates as a haylage took the best rank regardless of the quantity of fermented lactic acid. By this method, wafers could be stored for about a year or so.
6) The changes in nutritive values during hermetic storage were influenced significantly by moisture content when it was packaged, and not very much by wafer density. Changes in crude protain were very small, and crude ash, crude fiber and crude fat increased a little whereas NFE, carbohydrates and organic matters decreased a little.

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As the fundamental studies on lifting type diggers, pulling resistance force for root crops harvesting was measured.
1) The 95 percent confidence interval of the maximum pulling resistance force (Ymax) was as follews:
Carrot, variety “Gosun-ninjin” 3.0-3.8kg for sandy soil
Radish, variety “Syogoin” (1) 6.3-7.7kg for sandy soil
Radish, variety “Syogoin” (2) 6.7-7.9kg for sandy soil
Radish, variety “Aokubi” 6.0-7.8kg for Daisen-Kuroboku
Turnip, variety “Shimofusa-kabu” (1) 7.1-8.3kg for sandy soil
Turnip, variety “Shimofusa-kabu” (2) 10.3-12.5kg for sandy soil
Turnip, variety “Shimofusa-kabu” (3) 7.0-8.8kg for sandy soil
2) The results of the analysis of variance of Ymax under the same field condition revealed that the effect of root lengths was highly significant.
3) All of these specimen could be pulled up without cuteing of stems and damage of roots.

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The state of abrasion of blade edge and the stress distribution in Japanese-Hoe was examined by using photo-elasticity photograph
The results were as follows;
1) Abrasion volume of the blade edge of Japanese-Hoe was larger than the other parts, especially in right side. The fact that abrasion volume is not symmetrical on both side is due to the manners it is used, and the edge of right side is necessary to be reinforced.
2) The stress in Japanese-Hoe concentrates on a part of ETSUBO (handle hole in Japanese-Hoe) and the both sides of blade edge. When horizontalforce acts on it. The shearing stress in the both sides of blade edge was 2.1 times as large as the stress in ETSUBO.
3) The stress in Japanese-Hoe concentrates on a part of ETSUBO when verticalforce acts on it. In this case the shearing stress was 85 times as large as that when horizontal-force acts.

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Investigations of different types of banana ripening rooms have been made to collect data for aiming at the automation of process of banana ripening and some discussions were given to current commercial processing of banana ripening.
1. Actual conditions of banana ripening rooms concerning CO₂ and C₂H₄ concentration, ripening room temperature, pulp temperature of bananas, relative humidity during banana ripening have been obtained.
2. Those data have shown that current processing of banana ripeing in practice is conducted by skilled operators' own way.
3. Constant air circulation in a ripening room is remained as a future study for uniformity and more accurate control of room temperature during banana ripening. Combined effects of temperature, concentration of CO₂ and C₂H₄, variety of bananas and other factors as well as individual effect are also left for a further study.

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In this paper, the results of the analysis of oil used for the 50 hours runing test of water cooled diesel engine for farm use were mainly reported. The variable loading unit under programmed control was used for the experiments, which was already reported in the former paper.
Discussion of oil analysis were held on the following items shown in Table 2 such as specific gravity, color, flash point and so on.
The effect of STP additives was not found so cearly, therefore the further investigation including more experiments should be needed.

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