The purpose of this paper is to describe the results of the fundamental studies to make a threepoint linkage dynamometer for mounted implements at free float linkage position of hydraulic system. Their results obtained and further investigations are as follows:
1) It was imposible to keep a load distribution uniformly on a link pin dynamometer, in case that conventional plain bail joint of tractor link was used at the link pin dynamometer. For this reason, such a ball joint was not fitted for the purpose of transducer elements.
2) Adaptation of a self-aligning ball bearing in place of the plain ball joint, showed linearity in relation between load and strain at each pin dynamometer. On account of this, deviation of non-linearity at each pin dynamometer was obtafined at the ±5% level within the limits of 500-1500kg.
3) It is likely that right side lower link pin dynamometer curved upward at 0-300kg load was an effect of mechanical failure at strain beam. Then a reinvestigation to resolve this problem is called for.
4) Presently, the calibration curve adapted for the three-point linkage dynamometer was assumed to be true, taking a hypothesis that working depth of mounted implements was constant. Therefore, this work calls for fresh experiments to develop calibrating apparatus and method, and to investigate measuring accuracies of this three-point linkage dynamometer, since invariable calibration curve for this dynamometer should be secured without such a hypothesis.

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1. The three methods which represent shape of the face of a rotary tiller blade with the three wedge angles were shown, and the most simple, accurate and adequate representing method was selected. The first of the three methods is the three planes cutting method in which the action to soil is not considered, the second is the concentric circlar method in which the blade rotates around a point and the third is the trochoid method in which the blade rotates on a horizontal line with traveling.
2. The relative formulas between the three wedge angles by the three planes cutting method and those by the concentric circular method were obtained respectively, and the changes of the three wedge angles due to the change of tilling conditions were qualitatively shown.
3. Three wedge angles on main points of the blade face were measured and compared with among the three methods, and the characteristics of the action to soil and shape of the blade face were explained in comparison with those of the bottom plow share and moldboard.
4. From the above comparison, the followings were made clear. The three wedge angles of the blade face by the trochoid method were slightly smaller than those of plow, the states of their change were quite opposite to ploww and there was no turning action, and the cutting edge-particu-larly front end point (point E or F)-of the blade was main position of the action to soil.

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In this paper the authors described experimental studies on the relation of dynamics between the soil and the tire tread surface to the travel reduction, and a special emphasis was laid on the definition of a travel reduction ratio.
We provided a soil bin which was filled up with soft soil to make slip of the drive wheel. The tractor was moved on the bin, under varying conditions of the tire inflation, the wheel weight, and the pulling load, and the kinetic locus of the wheel was photographed. At the same time the pulling load and the strain of the deformed tire under tread were measured.
The conclusions were as follows:
(1) While the tractor travelled on the surface of such soft soil into which the lug surface of the tire sank, a given point of the lug surface followed a kinetic locus of looped trochoid curve. The shape of the spiral in the curve signified the rate of travel reduction. The travel reduction ratio has been usually expressed by the rate of reduction in the travelling distance with loaded state as compared with that at no load.
If the firm clod which was compressed between the lug was disconnected from the soil surface, was broken, and caused the wheel to slip, the term “slippage” was more appropriate than the term “travel reduction ratio” to express the situation.
(2) An unexpected low value (approximately 4.2 to 7.4 per cent) of travel reduction ratio was obtained when the clod which was compressed between the lug began to crack under the influence of pulling load. The travel reduction ratio at the time the lug clod was disconnected from the soil surface might agree approximately with that at the hign tractive efficiency. It seems that the tire began to slip at the moment of disconnection of the lug clod.
(3) While the lug penetrated into the soil and again emerged, the tire under tread was largely deformed. in comprssion. After the strain of comression reached the maximum value, this state was kept even when the pulling load was increaced. It was observed that the slip started when the under tread reached the maximum strain.

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Tests were made to evaluate injury of strawberry due to the shock of vibration and in-transit temperature in refrigerator-truck during the transportation for 700 kilometers from Fukuoka to Osaka, and the following results were obtained.
1) The average in-transit temperature in the truck ranged from 7 to 10°C, in spite of the aimed temperature of 5°C.
The highest temperature measured was at the upper space of the load just beneath the roof of the truck, and it seemed due to the heat of sunshine which passed through the roof.
2) On unpaved and uneven roads in strawberryproducing areas, many severe shocks were recorded.
On the refrigerator-truck, the heaviest shocks in transit were recorded in the uppermost packs of the rearmost location.
3) Laboratory test was run in parallel with the road test, and the quality of strawberry was evaluated in terms of weight losses, firmness, bruises, total sugar contents and grade ratings.
(1) The weight loss of transported strawberries (B) was 3.20% where as that of non-transpo-rted (A) was 2.96%.
(2) The ratio of the weight of bruised fruits to initial total weight was 32.7% in (A) and 50.5% in (B).
(3) The firmness of fruits of (B) reduced more than that of (A).
Strawberreis ripened by 40 Percent reached full ripeness after 4 days and were less subjected to injury owing to its high firmness of fruit during the transportation.
(4) Larger strawberries in size were more resistible against vibration injury than smaller ones.

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The heat transfer coefficients of the apple (Kokko), eggs (Leghorn and Gifu-Jitori), the Citrus (Unshu) and carrots in an air stream were determined from the cooling rate of the lead models of the products placed in the flow of air through a 20cm-diam poly vinyl chloride duct with a centrifugal blower.
The transient temperature change of the model was measured and recorded with a recording potentiometer (Shinkoh co., AS-11) employing copper-constantan thermocouples. The air velocity was determined by measuring the dynamic pressure at the head of the products with a manometer. The manometer was connected by a rubber tube with a 2.5mm glass pipe which was placed the model parallel to the air flow.
The results were expressed as the empirical formuras of the relation between Nusselt and Reynolds numbers.
The errors of this method which assumed no thermal resistance in the model were estimated for the lead model by using the solution to the equation of conduction of heat. It was found that the er rors were within 1.0 percent in the range of the experiment.

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The effects of the moisture content in midribs during the drying process of tobacco leaves while curing were studied.
1) Surface areas, moisture contents, and such other factors which are necessary to describe the drying process were determined for separated midribs and laminae respectively.
The moisture in midribs represents about a third of the moisture in the whole leaf. The amount of moisture per unit surface area is about ten times larger in midribs than that in laminae. Within the midribs, over 90% of the total moisture is concentrated in the cortex tissues.
2) In the early stage of curing, the moisture content of laminae was almost unchanged although the moisture content of midribs decreased considerably.
When midribs or laminae were separately subjected to curing, the water loss from the midribs was not so large, whereas the moisture content of laminae decreased markedly. Those results suggest that, in the early stage of curing, some of the water in the midribs is transferred into the laminae, where it is vaporized into the free air. In one of the experiments, leaves were subjected to curing to some extent and the leaves were then examined on their ability of water reabsorption. The results showed that, both in lamina and midrib, the majority of the cells maintained their water transfer activity during the curing.
3) To see whether the osmotic action participates in the generation of the driving force or not, the osmotic pressures of the cell sap obtained from midribs or laminae during curing were determined. throughout the experiment, the osmotic pressure of laminae was alway higher than that of midribs, indicating that the osmose had an important role in the movement of water within the leaves. The most probable reason for the higher osmotic value in the laminae seems to come from the saccharization of starch during curing. This conception was supported by a microscopic observation of leaf segments, where starch granules were gradually reduced both in number and size.

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For the sake of improvement of the physical properties of tobacco leaves, the course of dehydration and shrinking of the leaves during curing, especially the directional variation in the shrinkage and the correlations between moisture content and the shrinkage were studied.
1) The leaves were separated into laminae and midribs and the anisotropic shrinkages were measured respectively. No appreciable difference in anisotropic shrinkage was observed between longitudinal and lateral directions of laminae, both showing a value of 0.19-0.24. On the other hand, the value in thickness was remarkable (0.52-0.58).
As for midribs, the value in longitudinal direction was small (0.04-0.06), whereas the shrinkage in diameter was fairly large (0.46-0.53), showing the existence of a distinct directional difference in shrinkage. Microscopic observations revealed that the large shrinkage was mainly due to that of parenchyma cells.
On the whole leaf, it has been reported that the shrinkage in longitudinal direction is smaller than that in lateral direction.
The directiol discrepancy in shrinkage between the whole leaf and the lamina is explainable as due to the presence or absence of the midrib.
2) The apparent volume change, the true volume change and the shrinking strength were measured with laminae in order to see the relationship between the change in moisture content and the shrinkage.
The apparent shrinkage constant was reduced with the decrease of the moisture content ratio, although the curve was slightly convex upwards. It was also shown that the apparent shrinkage ceased near the moisture content ratio of 0.12. The true volume changed proportionally to thechange of moisture content.
The shrinking strength was relatively weak where the moisture content ratio lied in 1 to 0.6-0.7, below which the strength became considerably larger and reached a maximal value at the moisture ratio of 0.1 to 0.2. Any further decrease in the moisture ratio did not affect the value.
The relationships between the change of moisture content and the moisture transport mechanisms were also discussed.

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An infrared spectrophotometer was developed for the direct method of structural study of water contained in the inner epidermis of the bulb of onion. The direct method was to replace potassium chloride tablet method which was also discussed in the aspect of the effect of water on the infrared spectra.
The results may be summarized as follows:
1. The mixing of only potassiam chloride powder by agate mortar for 3min to form tablet increased the it absorption, especially at 3.0μ (3340cm^-1).
2. The effect of the mixing method of potassium chloride powder and soybean flour on the it spectra was found that the use of agate mortar intensified the absorption of it rays at 3.0μ (3340cm^-1) and 6.1μ (1630cm^-1). The vibration after agate mortar mixing did not remarkably increase the it absorptions.
3. There was no significant difference between the it spectrum of red bean flour of 1.56% moisture content and that of 12.57% moisture content.
4. On the whole the ir spectra of rice flour and wheat flour were similar to each other in appearance, while the it spectra of red bean flour, dwarf red cranberry bean flour and white kidney bean flour resembled each other. The it absorptions of soybean flour were relatively sharp in the spectral regions 2900-2800cm^-1 and 1740-1730cm^-1.
5. The increase of number of polyethylgne films (thickness of 0.03mm) increased the sharpness of ir absorption, but it did not obstruct the study of the structure of water.
6. Two layers of polyethylene covered water films indicated about twice the it absorption of mono layer of water film at 1630cm^-1, and the same relation was observed also at 3340cm^-1.
7. The ir absorption by the proper vibration of polyethylene was eliminated more in two layers of its film than in one layer. The ir absorption in the range1445-1435cm^-1 was related to proper vibration of polyethylene, and the absorption of free OH was at lower frequencies (3280-3240cm^-1) than that of absorbed water (3340cm^-1).
8. At 3240-3200cm^-1 the it absorption was observed in the case of the inner epidermis of the bulb of onion, while the it spectra of freewater was not so clear.
9. The ir spectra of fresh inner epidermis of the bulb of onion indicated that there was much adsorbed water, but that the amount of free water did not differ from those of the inner epidermises which were vacuum-dried or died in the space over 95% sulfuric acid respectively.
The quantitative analysis, therefore, of water adsorbed to the surface of various epidermises may be possible, while the free water may require to be scanned beginnig at 1650cm^-1.
10. Since heating of the fresh inner epidermis of the bulb of onion did not change its ir spectra, the adsorbed water to the surface of it may be similar to bound water in character.

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The dynamic frictional coefficients μ and animal taste of hay and wafers under many conditions were studied. Finally, all characteristics of hay or wafer were considered synthetically, optimum forming conditions were investigated and future subjects were described.
1. Hay and wafers did not show the true frictional coefficients μ when the normal loads were small.
2. Generally, the μ of ladino-clover was larger than that of orchard-grass and that on metal plate was larger than that on wooden plate.
3. The μ of hay or wafers generally increased as moisture content increased, but the μ value of ladinoclover was maximum when the moisture content was about 30%.
4. The μ of sliding plate sarface increased by painting.
5. The μ of wafers after one day was less than that of hay, and decreased slightly as final dry matter density ρ_d or holding time of compression increased.
6. Animal had a taste for wafers than hay, because wafers were easy to eat.
7. Low moisture hay was unsuitable to wafer forming, and middle or slightly high moisture hay was suitable from many points of view.
8. The final dry matter density ρ_d of 0.8gr/cm³ or thereabout was suitable for wafering.
9. The previous treatments of chopping or grinding were not suitable.
10. The suitable size and shape of expanded wafer for cow was considered to be about 60-70mm in diameter and 15-20mm in thickness (height)

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