This investigation was carried out to find the methods that onions were safely maintainable good quality during storage under cold weather conditions in Hokkaido. The quality of onions during storage was affected by the injury at mechanical havesting, and the thermal conditions of a storehouse.
The author investigated the rate of onion bulbs injured by an onion havester, the changes of atmosphere in the storehouse, and the inside temperatures of an onions bulbs.
The results are summarized as follows.
1. About 80 percent of bulbs was injured by the onion harvester, but these were almost cured under the conditions of relative high temperature and low humidity in a laboratory.
2. The inside temperatures in the storehouse were closely related to the open air temperature.
3. The minimum temperature of onion bulbs in the container which was nearly located beside the wall showed -4deg.C.
4. The relative humidity of central part of the storehouse were elapsed about 80 percent a little heigher than 70-75 percent of the appropriate humidity for storage.

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Four systems of automatic ventilation control for tobacco curing plastic house were studied in 1976 and in 1977.
Tobacco leaves were harvested and hanged at intervals of 5 days and proceeded to be air-cured for 10 days in each plastic house.
The ventilator operation was controlled by the dry-bulb temperture (35°C) at the house No. 1, by the wet-bulb temperature (31°C) at the house No. 2, by the dew point (30°C) at the house No. 3 and by the dew point (28°C) in 1976 and by the relative humidity (75%) in 1977 at the house No. 4.
Results obtained were as follows:
1. Dried leaves had normal appearance but different smoking taste in these four systems. The leaves with normal taste were only obtained by the dew point control at 30°C.
2. Precise control was performed by the dew point control and wet-bulb control. Proper ventilation was not operated in the daytime but the humidity stayed at the level lower than the aim at the house of relative humidity control.
3. The ratio of evaporative energy to total effective solar radiation at the house of dense hanging was higher than that at the house of thin hanging, and decreased in accordance with the number of curing days or the moisture contents of tobacco leaves.
4. The ratio has a practical meaning at the decision of reasonable hanging density.

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From the viewpoint of queuing theory, the distribution of arrival interval of users and time required to receive at the receiving section of paddy drying and storage facility were investigated. Generally the former was approximated by exponential or Erlang distribution, and the latter by Erlang distribution. In considering to the distribution of waiting time of users, and the idle ratio of facility, the receiving state was simulated, and the method to select the proper rate of receiving conveyor and proper arrival rate of users was proposed.

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The investigation reported here was conducted to provide data necessary for an estimate of the radiant heat load to housed animals and a design of thermal radiation environment in opentype livestock barns under summer condition. The experiments were carried out in 5 existing barns, each roof of which had different resistance of total heat transmission and surface absorptivity for solar radiation. The results were obtained as follows:
1) The average rate of downward all-wave radiant heat were measured as 400-500kcal/m².h. in the barn on a sunny day, and these values were equivalent to 60-80% of the outside horizontal solar radiation.
2) The downward radiant flux and the temperature difference between inside roof surface and inside air decreased as the thermal resistance of the roof increased. When the absorptivity of the roof surface was high, the effects of the thermal resistance on such reductions were highly significant, but scarcely appeared for the roof having low absorptivity.
3) The thermal resistance of the roof being high, the radiant flux depended on the outside air temperature, but it depended on the solar radiation while the thermal resistance was low.
4) To provide below 1°C temperature difference between the inside roof surace and inside air on a sunny day, the required thermal resistance of the roof were estimated as 0.6m².h.°C/kcal for the absorptivity being 0.7, and as 0.5m².h.°C/kcal for the absorptivity being 0.4, respectively.
5) Provided with low thermal resistance of the roof, it was seemed that decreasing the absorptivity of the roof surface was equivalent to increasing the thermal resistance of the roof for modifying the thermal radiation environment in opentype barns.
6) It was considered that the upper hemispherical effectual radiation temperature was a resonable index to evaluate the thermal radiation environment within livestock barns.

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