This paper proposed the probability considerations and the selective process simulations for the apparatus in which several fruit and vegetables were selected and packaged in a given weight range.
The bell pepper packaging apparatus which was actually used was taken to the concrete examples.
The detail weight distributions of bell peppers were measured, and the probability calculations revealed the necessary conditions to secure to select bell peppers in the range of 150 (g)≤W<152 (g).
Next, a selective process was proposed, and the computer simulation showed the smooth selection process and gave the evaluation of the accuracy.

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Atmospheric conditions in a disused rail road tunnel were surveyed, and then several vegetables such as potato (Solanum tuberosum L., cv. Toyoshiro and Norin-ichigo), Chinese yam (Dioscorea opposita Thunb. cv. Nagaimo) and burdock (Arctium Rappa L.) were stored in the tunnel for about three months.
The results are summarized as follows:
(1) An yearly average temperature was about 7°C at several locations ranging 100m to 500m from the tunnel entrance, and the humidity was kept at about 95%.
(2) Reducing sugar content of potato tubers increased gradually during tunnel storage, while its weight loss was only 1% after 3 months of the storage.
(3) Although the viscosity of Chinese yam tubers slightly increased at a beginning of storage, after that it showed gradual decrease.
(4) When the humidity in a tunnel is kept at 95% or more, it will be effective to store the burdock without polyethylene film.

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We have conducted a wind tunnel test to obtain data on wind resistance for the design of vinyl-house. Two 1/20 scale models were used, one is a rigid model, the other is an elastic model, and the approch wind direction was normal to eaves side.
In the rigid model, we used three gable roof-models, one with angular eaves and ridge, the others with curved surface. We found that each distribution of wind pressure are similar among of the models except in the area close to the eaves. The wind force (lift and drag) on the whole model also appeared to be the same value.
In the elastic model, we have changed the opening position and the opening ratio and then measured tensile force of the pressed down rope, bending stress of the frame and internal pressure.
The result shows that the mechanism of wind resistance remarkably depends on the opening position, but not depend on the opening ratio. That is to say, when the opening is located on the windward side wall, the covering plastic film will expand and the internal pressure coefficient will become positive. But, in case of the opening is positioned downwind, the internal pressure coefficient become negative, and the shape of the covering plastic film has no change. The model which has no opening or the opening on the both sides shows that the internal pressure coefficientis almost zero.
Under strong wind, the change of the shape of the vinylhouse is strongly effective on the lift, the tensile force of pressed down rope and the bending stress of the frame.
With these results, we devised relevant data of wind resistance for the design of vinylhouses.

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A comparative investigation of commercial vacuum cooling plants has been carried out to obtain the improvement instructions in both process control and cooling performance for a continuous operation.
Three models were selected from among the most typical systems operated in Japan, and their system's components, actual operating conditions and controlling methods and cooling performance of vegetables were evaluated by applying a standardized measure of vacuum cooling processes, which was defined from the viewpoints of most rational control procedures based on the cooling mechanism of vegetables.
The results and recommendations obtained from this study have been summarized as follows;
1. Although commercial vacuum plants are usually consist of two vacuum chambers, one or two cold traps and two or three oil rotary vacuum pumps as shown in Fig. 1, there are many variations in their design and combination as well as controlling methods of the components in a evacuation system, depending on the manufacturers and the steps of cooling process.
2. To compare and evaluate the controlling and operational methods of each plant, a standardized vacuum cooling process was defined by dividing it into four steps such as air-evacuation, flash-cooling, finishing and pressure recovering as shown in Fig. 2. The evacuation and controlling methods each model are classified as indicated in Table 2 by comparing these with the standardized process.
3. The features of controlling methods for each model of the plants as well as step of the process are summarized in Table 3 and the corresponding cooling characteristics of lettuce are presented in Fig. 3-5.
4. As the improvement instructions of the plant for cooling perfommance, controlling and operated methods, the following items have been indicated; namely a) the develapment of controlling method to set the timing from the air-evacutation stage to flash-cooling, predicting the flash point from the infomation of initial product temperature and the capacity a evacuation system, b) the rationalization of both assessment method for the refigeration load of the cold trap and c) the arrangement of evacuation system considering a required capacity of each cooling step. d) the finding of operational procedures to disappear the temperature gradients within the cooled vegetables which were found to be affected by the variation of the cooling load.
5. Although at present the process is essentially operated and controlled based on the chamber pressure, it is not necessarily considered to be an appropriate factor for monitoring the cooling conditions of vegetables. As an alternative, we have appointed the possiblity of the wet-bulb temperature in the vacuum chamber as a monitoring factor product temperature especially after the flash point of the cooling process.

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