The effects of wind velocity and wind incidence angle on the convective heat transfer coefficient were conducted through the model test with the wind tunnel. The wind velocity and the convective heat transfer coefficient for the prototype were estimated using the law of similarity based on turbulent Reynolds number and turbulence intensity. The coefficients that were used for calculations of the convection heat transfer coefficients of prototype were interpolated with the values of the parallel air flow pattern and the vertical air flow pattern.
In this study the comparison between the model convective heat transfer coefficient and prototype convective heat transfer coefficient were demonstrated. The correlation study showed a highly significant correlation between model value and prototype value. The approximate convective heat transfer coefficient of prototype can be calculated by using the interpolated scale up coefficient.
The relationship between the convective heat transfer coefficient and wind velocity were shown with regression curve. The gradient of regression curve for the roof showed the highest value. The gradient of regression curve for the gable showed the smallest value. So, the wind velocity significantly affects the convection heat transfer coefficients of the roof.
The effect of wind incidence angle showed different trend at the windward wall and leeward wall. The different trends were found in relationship between the convective heat transfer coefficient and the wind incidence angle at the each wall. The wind incidence angle significantly affects the heat transfer coefficients of the leeward gable and the leeward skirt. It affects about 10% to 20% of the convective heat transfer coefficientsin the other walls.
From these results, the functional formula that is based on the wind velocity doesn't give the exact convective heat transfer coefficient when the wind velocity is fast. However the functional formula based on the wind velocity and the wind direction can be applied for the determination of the convective heat transfer coefficient.

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To promote the flower-bud initiation in young strawberry seedlings (Fragaria×ananassa Duch. cv. Nyoho), tap water, chilled to 10-15°C, was supplied to the roots for 20-30 days in the NFT system before planting to the growing beds. The results obtained are as follows: 1) The 20 day treatment successfully promoted the bud initiation, still with a fairly high level of NO₃-N, and better crop growth until the final planting. 2) An earlier flowering was promoted for the terminal flower cluster by the 20 day treatment, but on the contrary, the 30 day treatment brought about a flowering delay. However, 30 day treatment created simultaneous flowering for the terminal flowers. 3) The 30 day treatment also made the flowering of the axillary flowers short, and offered simultaneous flowering to the whole crop, repectively.

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The automated ice making system consists of three main components: a water discharge system, an air distribution system and an ice container.
One of the components of the water discharge system is a discharge apparatus called the Fountain Unit. The Fountain Unit is one of the simplest time-temperature integrators available, and serves to control the volume of water discharged per hour in proportion to the ambient air temperature. Low temperature outdoor air is blown onto the ice surface using a fan and ducts.
The ice container, which is located directly below the Fountain Unit and spraying nozzles, is simply made of cloth suspended from a scaffold. Once water that is sprayed on the cloth freezes, the cloth has enough strength to support a thin layer of water on the ice block surface.
In order to make a clear ice block, the volume of water released should be controlled so that only a few millimeters of ice are created during any single discharge interval.
In practice, a water temperature setting in the Fountain Unit of 2°C was found to be satisfactory. The air volume should be adjusted so that the Freezing Index is 150°C·min·mm^-1. This system can be used to create a block of ice over 3 meters high by making use of low outdoor air temperature conditions.
Large blocks of ice are ideally suited for the storage of agricultural products because they can provide both low temperatures and high humidity. The ice block created in this study was used to store vegetables without significant deterioration in quality for 2.5 months.

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Physical properties such as density, cohesion, and angle of shear resistance of manure, and pressures on walls of on-farm manure shed were measured.
As results of these measurement, static pressures of stored manure on walls were estimated extremely lower than the ordinary soils, and dynamic pressures due to agitation by vehicles were equivalent to the value of the maximum traction capacity of the vehicle divided by the area faced forward of the bucket equipped.
From these results, simple method to estimate the design wall loadings of manure shed is proposed.

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The determination of the desired values of climate factors is important for achieving contorl environment of greenhouse.
Investigations about semi-forcing culture of tomato were made for 20 farmers in Niigata prefecture. With the results of investigations, such as yield, cost of heating, quality of fruit, growing stage, weather and horticultural experience ete., the optimal set-points were realized by fuzzy inference. Besides this, to reduce the consumption of energy and also to improve the response characteristics of control system, the climate control experiments in the model house were carried out using fuzzy theory. The threshold for set-points can be made change according to the rate of change of temperature and humidity, the properties of this control system were examined. In comparison to this control, the general ON/OFF control experiments were also made.
As the result, for the temperature control, the errors of the fuzzy control is less than that the ON/OFF control. For the ventilation control, the control error is less than the ON/OFF control. For the sophisticated control of temperature and humidity, there is no difference between fuzzy control and ON/OFF control for temperature, but for humidity the overshoot and control error are restrained as low level for the fuzzy control.

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There is a growing interest in mechanization and automation to save labor and allow the large-scale greenhouse operation. The environmental pollution caused by the pollutants discharged from greenhouses is strongly concerned as a critical problem. Therefore, modern greenhouses should meet these demands.
The progress and current status in the Japnese greenhouse industry are examined in comparison with the trends in the advanced countries. Several sophisticated commercial greenhouses in Japan, the Netherlands, and the U. S. A. are reviewed.
The perspective in greenhouse technologies for automation and reduction in environmental impacts is discussed.

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