For the location planning of agricultural structures, important factors are;
i) disposition of facility in rural region, ii) space arrangement of the facility within a site.
The purpose of this investigation, as the basic research for the studies on the location planning for agricultural structures, is to find out some data to an optimum design of space arrangement for paddy drying and processing facilities (especially, so-called “rice-center”; RC).
The results obtained were summarized as follows;
1) There were various patterns in the sites for existing facilities, and some of them were found to cause some troubles, such as the problems for worker's health and safety, or the uncomfortable living environments.
2) On these complex site patterns, the author tried to introduce a term “apparent site area”. Using this term, it became possible to compare the space constitution factors to each other.
3) Certain relations were found between the total of apparent site area and its constituting factors, and some of them expressed with the linear functions (Eq. (5), (6), and (7)).
4) It seemed properly in practice that the facility space and outdoor working space were considered as the major factors constituting the site area.
5) From the result mentioned above, the relation between site space factors was recognized in actual condition, and the basic guide for site planning was obtained.

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Some experiments on the controling methods for greenhouse temperature in summer were conducted.
(1) Mist and fan evaporative cooling system was most effective among cotrol methods of summer greenhouse temperature, such as natural ventilation with or without shading materials, forced ventilation and the evaporative cooling methods.
It was recognized from the results of observation that is inside temperature 3.0 to 6.0 degree higher in natural ventilation, 2.5 to 3.0 degree higher in forced ventilation, 1.5 to 3.5 degree higher in natural ventilation with shading cloth, and approximate equal in the evaporative cooling methods as compared with outside air temperature, respectively.
(2) Temperature difference of inlet and outlet of ventilating air in the evaporative cooling glasshouse was enlarged by solar energy considerably.
(3) Solar transmittance ratio into glasshouse, were found to be 60 to 75% without blind, 30 to 45% with shading cloth (1.6mm opening, #600, black) and 25 to 30% with marsh-reed blind.
(4) The spray effciency or cooling efficiency in the evaporative cooling system was analysed to be about 1 gram per 1kg air rate in the mist room and 51.2 gram per 1kg air rate in the glasshouse.
Improvement of the cooling efficiency and reducing of the temperature difference in a glasshouse with evaporative cooting system will be next problems of atmost importance.

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本論文では, 常時液相と気液二相の水耕方式の違いが葉温と茎内水分の計測から検討された。光のステップ入力 (0luxから30,000lux) による蒸散の同定が葉温と静電容量の情報からなされ, 一般に蒸散は気液二相の方が常時液相よりも大きかった。また, 気液二相の間欠は30, 60, 120分サイクルについて検討したが, 60分サイクルの場合が最も蒸散が活発であった。

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In orchards and tea-gardens, sprinkler systems have been installed for applying rather agricultural chemicals and fertilizers than irrigation water. In future they may be used to apply herbicides, fruit ripeners, and chemicals for picking excessive flowers or fruits.
Uniformity of application, which is specially required in applying these chemicals, is affected by variations among discharges of the individual sprinklers. Using pressure regulators or flow controllers on the sprinkler nozzles, the variations are made even. But it cost the farmer as high as the price of the sprinkler nozzles.
For saving the equipment cost, we contrived the method to uniformalize the pressure at a nozzle by a orifice that fitted in each applying point. The optimum orifices were selected experimentally from measuring the primary pressures of pressure regulators and from pressure drop diagrams of the orifices Fig. 5 or Fig. 6.

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Many analyses of temperatures in stored grain had been reported using boundary condition such as the changes in only ambient air temperature. In this study, the grain in cylindrical bin was regarded as the infi nite cylinder, and the equation for predicting the grain temperatures was given as the partial differential equation in which respiration heat of the grain was considered. In the equation, it was assumed that heat flow was only in the radial direction.
The above equation was solved by the finite differences approximation using digital computer.
Computing the above equation, the following boundary condition was applied; it was outer wall temperatures of grain bin which was calculated in relation between the ambient air temperatures estimatimated by means of Monte Cairo methods and the heat gain with solar radiation and/or the heat loss with long wawe radiation at the surface of bin wall.
The predicted grain tewperatures were compared with the observed.

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The performance of perforated inflatable ducts was investigated, and practical equations and coefficients were derived to permit the design of such ducts for ventilation of greenhouses and livestock buildings.
1) A mean static pressure in a perforated duct was needed as high as 1.0 to 2.5mm water gauge, at above which the duct stayed inflated.
2) The critical factor in the performance of perforated inflatable duct was the ratio of total exit hole area to duct cross-sectional area, termed “aperture ratio”. With the duct having larger value of this ratio, the static pressure and discharge air velocity near the closed end were greater than those near the fan.
3) The distribution of the static pressure and discharge air velocity along the duct were determined with only aperture ratio when the duct length, duct diameter, and air flow rate of fan were given. These distribution were not influenced with the size and number of exit hole.
4) Air discharged from holes near the fan had considerable tangenitial and downstream components of velocity, but discharge air at the closed end was normal to the duct These tendencies were pronounced with the duct having larger aperture ratio.
5) Equations were derived to predict air velocity and static pressure in duct and discharge air velocity from the exit holes (Eq. (8), (9), and (10)).
6) Some coefficients required in above equations were determined (Tabl 3 and 4).
7) Calculated values using those equations and coefficients agreed with measurement when the aperture ratio ranged from 0.6 to 1.8.

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