1) When the same plunger pump was used, the maximum power decreased with the increase of water in emulsified fuel, as shown in Fig. 1.
2) The specific fuel consumption of emulsified fuel decreased, when compared with values obtained with gas oil, as shown in Fig. 3.
3) With the increase of water in emulsified fuel, the ignition delay, the maximum pressure and the rate of maximum pressure rise became large, and the crank angle which produced the maximum pressure had a lag.
4) The indicated thermal efficiency of ernulsified fuel was better than the gas oil.
5) In the case of above W/F=0.5, a phenomenon of miss-fire occured at idling and the blue smoke was emitted. Its frequency was in proportion to water/fuel ratio (W/F).
6) As W/F was large, starting performance was bad. In the case of W/F=0.3 hand starting motion was about ten times.
7) There was no corrosion in this experiment, but further investigation seemed necessary for long runs of the engine.
8) If additives were not used to improve the cetane number of emulsified fuel, the authors would think that the limit of W/F ratio would be 0.3 for the corhbination of the phenomenon of miss-fire and starting performance.

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To calculate more exactly the value of side force of pneumatic tire on the theory of E. Fiala, the applicability of the new theoretical equation which was expanded under the assumptions that the coefficient of friction increased linearly with the deflection of tire to the coefficient of maximum friction (f) in the adhision zone of contact patch of tire and turned to the coefficient of dynamic friction (μ) soon after moving into slip zone, was investigated on smooth and agricultural tires.
Main results are as follows;
1. The relations between side force (S) and side slip angle (β) are assumed as follows;
When 0≤β<β_n,
S={Ctanβ-C²/3f(2-μ/f)tan²β+C³/27f²(3-2μ/f)tan³β}W
and when β_n<β≤90°, S=μW,
where, β_n=tan^-1(3f/C),
and C is a factor of cornering coefficient. Using the chi-square criterion, the hypothesis that the side force calculated with these assumptions is equal to the experimental value acceptable at a level of 0.01.
2. As the dynamic frictional resistance of tire is directional and is indicated by the half length of the diameter of elliptical shape, experimental value is evaluated on the values of side force calculated by the upper equation on both circle and ellipse of friction. From the results of these calculations, it is recognized that the method by the ellipse of friction is more suitable than another for the agricultural tire, though it is slightly better for the smooth tire.
3. The values of f and μ, obtained from the results using a least squares method become larger with the increase of tire inflation pressure and with the dicrease of supporting weight of tire, respectively. The value of C becomes smaller with the increase of supporting weight of tire.

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The human engineering research efforts on the driver's seat and controls were concentrated on investigation of the problems involved in them and on anthropometry for the farmers.
From our study on the dimensional adaptabilities and handling properties of 90 tractors, some improprieties were found in the range of seat adjustabilities, seat surface height, location of foot control pedals and direction for applying pedal thrust.
Twenty-seven anthropometric iteme were measured for 153 farmers. As compared with other data, the data thus obtained were closely similar to those of anthropometry of Japanese pilot. This similarity might be owing to the age distribution of our subjects, which concentrated in 18-22 years old.
The results of the study on the driver's seat and controls with respect to human engineering based on anthropometric data are as Fig. 10.

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Following analyses were carried out to clarify torsional vibration of rotary tine shaft during operation for sand: 1) computation of power spectral density (PSD) for tine shaft torque and XYZ-directional accelerations, 2) numerical analysis of natural frequency for utilizing Holzer's successive method. Several findings can be drawn as follows.
(1) In the case of deep tillage (around 10cm deep), the contained frequency components of tine shaft torque vary with inherent fluctuations at the higher frequency region. On the contrary, in the case of shallow tillage (5 to 6cm deep), the significant frequency region spreads with the increase of tine shaft speed.
(2) It is of interest to note that, in X-directional acceleration, only tine shaft speed affects to the PSD tendency in no-load condition. What is more, the number of tines play important roles to transfer the frequency component characteristics in shallow tillage.
(3) It is clearly evident that Y-directional acceleration shows dominant magnitude of PSD at 5 to 10f₀ in no-load condition.
(4) Any salient trends can not be discerned for Z-directional acceleration in no-load condition. This seems due to bouncing of the chassis.
(5) Using Holzer's successive method, it can be predictable that the thickness of rotary tine shaft and its mass distribution affect natural frequency of rotary tine shaft.

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1) We investigated the abilities of tilling tines when the water content of two kinds kinds of soil was changed.
(1) In plastic range, the lower water content brings on the smaller size of clod, the relation being linear.
(2) The spading tine, especially L-shaped tine N₈ shows great soil pulverizing effect and is under the influence of water content. But the tine Hn shows relatively high soil pulverization even in high water content.
3) The relation of specific torque for tilling and water content is also linear. The higher the water content, the lower the specific torque.
2) The works by four methods of seedbed making tillage were compared on three kinds of soil of equal water content.
(1) In the case of multi-pass tilling, the weight mean diameter of clod and specific horsepower are proportional to the -n power of number of pass.
(2) The merit of sieving tillage is the homogeneous pulverization of soil and the controllability of clod size. In this case, soil pulverizing effect becomes great when clay content is high.
(3) In the case of one-pass tilling (shield tillage, harrowing rotor and sieving tillage), the work needed to get the weight mean diameter of 10mm becomes about 1/10.
(4) The relations of the works by multi-pass and sieving tillage and clay content of soil are exponential and logarithmic, respectively. The works increase as the clay content higher in each case.
(5) Among the four kinds of methods the sieving tillage brings the highest soil pulverization
(6) The works for seedbed making tillage by harrowing rotor and sieving tillage are less,
3) Our trial calculation for the strength of main parts in case of doing seedbed making tillage by the commercial rotary tiller, resulted in the safety rate of more than 1.3 and assured its security.

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The tests were carried out on a weedy paddy field and the field after mowing of wheat, Italian rye grass and rapeseed. These tests have been done in connection with number of tines (32, 16), speed of rotary shaft (high, medium, low), forward speed (0.2m/s, 0.4m/s), tilling depth (10cm, 5cm), number of tilling (1, 2) in the rotary tiller of 55cm width.
The results were as follows;
(1) In the field after wheat, rapeseed and the uncovered field, the size of the increment of cut had a little effect on the pulverizing action.
The pulverizing action of fairly large-sized iccrement of cut was good too.
(2) In the field after Italian rye grass, the pulverizing action of small-sized increment of cut [Hm0.2] was very excellent, and we were able to seed at once there.
(3) The puverizing action of 32 tines was generally better than that of 16 tines in the same lead. There was large difference between 32 tines and 16 tines in the pulverizing action on the fields after Italian rye grass and weedy paddy field. But there was small difference in case of the field after wheat and rapeseed.
(4) In the same sized increment of cut, the pulverizing action in tilling depth of 5cm was better than that in the depth of 10cm, except Italian rye grass.
(5) The pulverizing action in double tilling was nearly equal to that in one tilling.
(6) The pulverizing action in the field after Italian rye grass was worse than that of the other crops, in the same increment of cut.
(7) Power requirement of the rotary shaft in the field after Italian rye grass showed about 10% increase compared with that in the field after wheat in same tilling depth and increment of cut. The power for tilling to the depth of 10cm in the field after Italian rey grass was excessive for the engine.
(8) The power requirement of the rotary shaft in 32 tines and high speed was very large. That of [Hm 0.2] and [Ll 0.4] was especially large.

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The authors applied the weeder to directly seeded paddy field and obtained the following results.
(1) When the weeder was used at germination time of paddy, the germination percentage was rather heightened.
(2) When the depth of tines of weeder was 2.5cm and the interval of locus of them was 1.25cm which were standard working conditions, losing ratio of rice plant was 5-10% and that of rice stubbles was nearly 0%. But if the soil moisture was above 40%, d. b. loss of stubbles was found a little because the stubble were buried under soil.
(3) When the weeder was used to the weeding after rotary tiller broadcasting and to working the weeding after submerging, loss of rice plant was almost none.
(4) Lossing ratio of weed was about 90% in standard working conditions, but that differed more or less with depth of tines, soil moistures and times of working.
(5) When various weeding methods were compareds during thirty days after seeding, the weeding effect of using the weeder together with DCPA was best and that of the weeder only was the second and that of DCPA only was the third.
(6) In a rainy season, perfect weeding of wild sawa millet was carried out when the weeder was used once after two applieations of DCPA or when the weeder was used twice after one application of DCPA
(7) Using the weeder with standard working conditions, the adaptability of the weeder for directly seeded paddy field was recognized good enough even if the use was made during the rainy season.

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Tne effects of some factors on the shear characteristics of several artificial soils were analized mainly dy the method of analysis of variance, and the shear characteristics of artificial soils were compared with those of natural soils. The results are as follows:
1) Oil effect. In the case where 40W motor oil or 90W cylinder oil was used, the viscosity of the soil is more than that in the case of 10W motor oil. But there was scarcely any differences between the cases of 40W motor oil and 90W cylinder oil.
2) Sand effect. There was not so much difference of shear characteristics between the cases of pure dry sand and ordinary sand.
3) Bentonite effect. The shear strength and the viscosity were increased when the bentonite was mixed owing to the property of bentonite as a kind of binding agent.
4) Oil content effect. Oil content has much influence to the shear characteristics of artificial soils. If the oil saturates, the artificial soil has scarcely any shear strength. The oil contents of saturation were about 27% in the case where the bentonite was used, and less than 20% in the case of no-bentonite.
5) From the comparison of shear characteristics of natural soils and artificial soil which consisted of 90W cylinder oil and equal amounts of ordinary sand and bentonite. It was found that the shear characteristics of artificial soil were similar to those of natural sandy soil, sondy loam or loam and viscous soil in accordance with the oil contents.

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Regression analysis of the extended frictional equation of the form
S=c+K_σ·V^2(1-m)·σ^m+K_V·Vⁿ
…|F, a|
in which c, a, K_σ, K_V, m and n are soil values, S is internal shearing stress, F external shearing stress, σ normal stress, V shearing speed and the nomenclature |F, a| means F and a are exchangeable with S and c was conducted by Deming's the least square method and the soil values and 95% error band were obtained:
1. In internal shearing, the existence of all the soil values was confirmed on compacted sandy loam. Soil values c, K_V and n were obtained on soft clay in which K_σ was assumed zero, while c and K_σ on dry sand and loose sandy loam in which m and K_V were assumed unit and zero respectively, so that here the equation is reduced to Coulomb's.
Description on internal shearing could be applicable to external one except that the value of m which is smaller than unity was obtained on dry sand and loose sandy loam.
2. By examining 95 percent error band, the authors concluded that the equation is valid for describing dynamic soil-shearing resistance in high-speed shearing except for the case of external shearing under excessive high-speed.

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1) The mean air velocity V and the penetrating flow rate at a section of a p. d. head (an abridgement of perforated dust head) were calculated by multiplying the pipe factor (Φ=V/V_c) to the central penetrating velocity V_c, because it was good enough for such quite a small section. This method of calculation made it neccessary to measure the pipe factor of the p. d. head.
The maximum velocity at a section was biased from the central axis toward the perforated bottom wall. The pipe factor Φ was affected by the opening ratio R₀ of the wall as shown in Fig. 5 and was expressed by equ, (13) practically, Besides, Reynolds' number did not always affect the pipe factor Φ.
2) From the fact that the decreased amount of penetrating flow rate between upper lower sections is equal to the total discharge rate from outlets in a given division, the fluidal mechanism of the branching discharge and the coefficient of discharge C_d were elucidated experimentally, and were shown in Fig. 2-3 and expression (8) or (10).
The actual discharged air stream originated at the depth of nearly 4.5mm=η from the front edge of each outlet in every head. (Table 1-2)
The discharged quantity qi from a given outlet was expressed by the next formula,
qi=C_dγ₀/γ_aυaicosθ√1+(V_η/υ)²
or
qi=C_d(V_ηsinθ+γ₀/γ_aυcosθ)aicosθ
where, V_η= penetrating velocity at the η=4.5mm depth, υ= assumed divergent velocity calculated with the static pressure. The sectional area of a discharging stream should be made equal to the projected area of the outlet toward the discharging direction.
The discharging inclination θ and the coefficient of discharge C_d were expressed as functions of Φ_η (the rate of co-perpendicular streams V_η vs. υ).

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The straw compression pressures acting on the clutch door of binder at the binding of sampled sheaves analyzed in previous paper (References 1 and 2) were discussed on its relation to the tightness of bound sheaf
Results obtained were as follows.
1. According to the binding mechanism and its timing action of a tested binder (One row type), the relationships between the angular movements of binding shaft θ (deg) and the straw compression pressure acting on the clutch door were investigated (Fig. 1-4)
2. The changes of the straw compression pressure F (kg) with θ (deg) measured by strain gage method had good agreements with the timing action of binding device. But the variations of F at θ were very large among samples (Fig. 7).
3. The variables PFΘ(kg/cm²) obtained from F, the door area and the unit angular movement 15°(deg) from 0° to 195°(deg) of θ were defined and calculated on each sampled sheaves. And mean values, standard deviations and coefficients of variation of PFΘ were discussed (Table 1 and Fig. 8).
4. The maximum straw compression pressures PF_max (kg/cm²) of each sampled sheaves occured at θ=160°-195°(deg) were analyzed using variance analyses.
PF_max was affected by the physical properties of straws and twines (Source of variation E (1)), the setting position of clutch door for the adjustments of sheaf size (Factor C) and its interaction with the kinds of twines (F×C) (Table 2).
The interval estimation of mean values (95%) to PF_max with the levels of Factor C were obtained as 1.38-1.04(kg/cm²) in big and middle size sheaf and 0.94-10.60(kg/cm²) in small size sheaf.
It seemed that the variation of PF_max was similar to the variation of the specific values P1 which expressed the tightness of sampled sheaves because the significance of variation sources and their contributions were the same (Fig. 9).
5. P1/PF_max of each sampled sheaves were analyzed to evaluate the binding looseness (Table 3). And the interval estimations of mean values of P1/PF_max were obtained as 55-84% in big size sheaf and 39-68% in middle or small size sheaf.
As P1/PF_max was changed with the levels of sheaf size, it seemed that the shorter the sheaf twine length the greater the binding looseness.
The effect of twine on P1/PF_max was not significant as the variation of each sampled sheaves were large.

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Some basic experiments were performed on aspects of fluidizing behavior and heat transfer of fluidized beds of unhulled rice. A summary of the results is shown below.
1) Onset velocity of fluidization increased in proportion to initial bed height. Therefore theory of M. Leva was inapplicable to fluidized beds of unhulled rice, but the simplified equation (10), suggested by C. Y. Wen et al could be used.
2) Mode of fluidization was strongly influenced by the type of distributor used. Within the limits of this experiment, it became evident that the packed bed of steel ball was the most excellent distributor for fluidization.
3) Apparent coefficient of heat transfer between grain and air decreased in inverse proportion to initial bed height.
4) In general, apparent coefficent of heat transfer between grain and air increased in proportion to air velocity, but a cooling of grains in dense phase was the most efficient method.
5) The result of the above (4) was correlated by the following equation. The value of the Nusselt number for Pr=0.7, 500<R_ep<1200 approached the Nusselt number in heat convection for a single sphere.
h_pD_p/k_f=0.0137(D_pρfU/μ)^0.939, (r²=0.87)

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This report presents a simple measurement apparatus for poisson's ratio of agricultural products which was devised based on measurement method of the small volume change of cylindrical test pieces by uniaxial compression deformation. We measured the poisson's ratio of sweet potato (SATSUMA IMO), potato, carrot and rubber stopper by means of the measurement method with the apparatus and reported the data of the poisson's ratio and compressive elasticity of each of them. At present, it is difficult to measure the ratio directly but the results thus obtained have considerable reliability.
The experimental results are summarised as follows:
1) In the values of mechanical properties of agricultural products, especially in poisson's ratio and compressive elasticity, the deviation of the measured values was large even if samples from the same species were used.
2) The obtained values are summarised as in the next table.

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This study principally purposed to analyze the vibrating system which consisted in a shaker body, a boom and tree limbs, and to find the design criteria for a boom-type shaker. It was so difficult to express this system mathematically that the system was assumed to be a lumped-constant model as shown in Fig. 1. In this experiments, a boomtype shaker mounted on 4-wheel tractor was used and limbs of cherry trees were shaken at various frequencies and strokes. The boom was made of an aluminium tube of about 5m in length and 6cm in outer diameter. The main results obtained were as follows;
1. With the heavy shaker-body and the light and stiff boom, large shaking forces could be effectively transmitted to limbs, from the shaker. For ω>>ω₀ (where ω₀=natural frequency of limb), the shaking force and power increased proportionally to the square and the cube of the frequency, respectively.
2. The average shaking force in practice was about 400kg and the maximum force came up to 1000kg. The maximum force was nearly equal to the calculated value. The total power was 10-20PS and the net power required for limb shaking was 5-46PS.
3. There was an inflection at 1000-1200cpm in the both curves of the force and the power versus frequency. It seemed that the natural frequency of limb was 1000-1200cpm.
4. The vibration intensity, the effective value of acceleration, was approximately 40G at the clamp position on the limb and the peak value of acceleration reached 120G. The net power per 1G was 0.15-0.4PS and it increased as the clamp position approached the crotch of limbs.
5. The actual strokes at the clamp position were smaller at 800-850cpm than those set by the shaker, but were larger at 1000-1200cpm than those by the shaker. The shaker-body was shaken in the displacement of 0.3-0.6cm due to the shaking reaction of limbs.
6. By the correlogram and the power spectrum analysis, it was found that the most distinguished frequency of limbs was that set by the shaker However, there were some higher frequencies effected by the boom deflection, engine revolution, supporting manner of the shaker and the others in the vibration of the shaker body.

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The characteristics of a rolling-compressing wafering machine for grasses, legumes and rice straw were studied, and the following results were obtained.
1. Mixture materials of italian ryegrass and rice straw as well as rice straw and soybean could be wafered.
2. Material from fresh harvest down to 23% moisture contents could be wafered in this experiment. The wafer in high moisture content exhibited difficult problems in drying and storing, and with the moisture contents lower than 30%m. c. wb, (especially legumes) also exhibited losses by breakages of the fibers, and its sulface was loose and rough.
3. Wafer slippage rised at lower moisture contents of 30%, and rolling-compressing was impossible below 20% moisture contents on account of slippage or blockage at the intake, For rolling-compressing at low moisture content ranges, the friction coeffieient between material and rollers had to be enhanced.
4. The alteration of the torsional angle and the rotational speed of the rollers almost had no influe nce on the driving shaft torque, and consequently machine capacity became higher by the increase of the torsional angle and rotational speed of the rollers.
5. Radial force was generally weak and power requirement was low, and in case of italian ryegrass, its specific power was approximately 1.5-3.0 PS-hr per ton at 700kg/m³ and at 49% moisture contents.
6. Wafer durability increased with the increase of wafer density, and the moisture content within the range of 35 to 50% provided good durability.

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Wafers and cubes of Italian-ryegrass were made with roller-die type apparatus, and their characteristics such as change of density, tensile strength. falling shock durabity, ASAE tumbling durability, cone penetrating resistance and drying rate were investigated. From these characterestics together with those of resistance forces and waferability reported in the preceeding paper, the following results were obtained synthetically:
1. The density ρ of wafer was a reliable index for indicating the intensity or durability of wafer and its maximum value was obtained at abont 20% moisture content (wet basis) of hay. For dried hay (20% mc), the ρ value with tapered die was smaller than that with standard die (No. 1) and for wet hay (40% mc) the former was fairly larger than the latter. On the other hand, the ρ values with inclined die and cubed die were smaller than those with standard dies of No. 2 and No. 1 respectively. The ρ of dried wafer (12% mc) was smaller than that of undried wafer just after formed, while that of wafer of rehydrated hay by spraying was also considerably smaller than that of on-ground-dried hay at the same moisture content. The ρ value at 100°C of hay temerature was always larger than at 80°C. The ρ characteristics of wafers of italian-ryegrass and that of guinea-grass were almost the same.
2. The temsile strength T of wafer was also a reliable index for intensity, because the tendency of T value was almost the same as that of ρ value except that the T of the wafer dried to 12% mc was larger than that of just after formed. The T value of italian-ryegrass was smaller than that of guinea_grass.
3. The F value of falling shock durability (rate of residual weight) was scattered probably due to the data calculated by ASAE method without using the same mean weight of wafers. The A value from ASAE tumbling method changed little with varying me of hay from 12% to 30%. Hence, F and A values were not suitable for the valuation of durability in this investigation.
4. To evaluate the durability of wafer. the physical and the practical methods may be taken. For the practical method, the total weight or total volume of samples extruded must be held constant, and the available minimum weight (or volume) of samples must also be held constant in the processing after fallen or tumbled. The falling height and the falling times of falling method and the tumbling speed and the tumbling times of ASAE method must be properly determined respectively by the conditions.
5. The maximum resistance force of cone to wafer for die No. 1 was obtained at 20% mc. The resistance force P_c of dried wafer (12% mc) was smaller than that of undried just formed, and the P_c of wafers formed from the rehydrated hay was also smaller than that from on-ground-dried hay at the same moisture content.
6. The drying rate of wafer formed by hay of 40% mc decreased to zero after 2 to 3 hours when dried in the oven at 100°C. The mean drying rate of cube was smaller than that of wafer. The drying rate of wafer formed by inclined die was higher than that of straight die at the early drying stage, but the wafer of tapered die was harder to be dried than that of straight die.
7. As a whole, good results were obtained with the hay of about 20% mc and 100°C, but rehydrated hay was undesirable for wafer forming. It was considered that the valuation of waferability and wafer density indicate the intensity or durability of wafer satisfactorily.

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In this paper, the results of the measurment of the frictional coefficient of the tire rubber to the various surfaces are reported.
Three kinds of boxes having the different contact area of tire rubber attatched to the bottoms of them were prepared and pulled. Vertical load was added to each box in each test. The pulling force of the box was detected with the load cell with strain gage on it. Four varieties of surfaces were prepared. Those were: wood, soil, mortar and concrete. For soil and concrete surfaces, the Amonton's law was valid, but not to the others. In general, the measured static coefficient of friction was larger than the kinetic one.
An obvious result on the relation between the kinetic coefficient of friction and the relative moving velocity of tow bodies was not obtained. Soil constant measuring instrument, TN-4 was used to see the validity of the obtained data by the pulling method. Both results were quitely coincident.

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