In the design of a Paddy Drying and Processing Facilities, it is difficult to make operational decisions because of the conditional variation of location, weather and production capacity. The information on the receiving process of paddy rice is required to solve these problems. In this study, the operation of country elevator was investigated, and the collected data were analyzed with a statistical method. Also, an approximate mathematical model was established for the calculation of predicted receiving amount, weight and moisture content of paddy rice.

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This paper describes a accumulative mix storage drying of paddy grain in a large scale steel bin having a capacity of 150 tones. In this drying method, a certain amount of just harvested grain at high moisture content is stored in the bin, while being constantly dryed and mixed. The grain harvested in the following day is then mixed and dryed with the grain in the same bin. The process is repeated untill the bin has been filled, and the drying process is continued to make the grain moisture content reach a set value.
The storage drying for 20 days makes the grain moisture content dryed in 15.5%w.b. with less 1% in standard deviation. The quality of the grain dryed by this method proved to be the same as the grain dryed in the conventional ways of natural drying and heated air drying, when considering evaluations of kernel cracking, germination, embryo activity, free fatty acidity and taste.

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For the design and development of a high performance methane fermentor, the anaerobic fluidized bed fermentor was evaluated in order to determine the characteristics of this fermentor. The obtained results are summarized as follows:
1. When the fermentor was operated at less than a 0.38 dilution rate (D, 1/day), more than a 85% substrate (acetate) removal ratio could be observed. When D was over 0.38, the value of sludge retention time (SRT, days) was less than 10 days and the substrate removal ratio decreased.
2. When the fermentor was controlled at a high D, the methane microbes retained on the support media were reduced and consequently the microbes in the mixed liquor increased. As a result, the SRT of the fermentor was decreased.
3. Using the kinetic model modified here, growth characteristics such as μ (1/day) and Y_G (mg/mg) of the methane fermentation process were determined. These values indicated that methane microbes contained in the fermentor showed relatively low substrate consumption and growth rates. On the other hand, the concetration of methane microbes in the fermentor was high. This might be one reason for the higher performance of the fermentor.
4. It was suggested that high performance of methane fermentor with a high concentration of methane microbes even if the activity of the methane microbes was relatively low.

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When producing ice in ice ponds with layer-by-layer applications of constant thickness water sheets, the simplest method to determine water spray intervals is obtained by considering the amount of “coldness”. This study considered that both outdoor air temperatures and wind velocities affect ice formation rate greatly, and we developed equations of the relationships by experiments. A computer program to automatically control water spray intervals with the newly introduced coldness values was developed, and the study yielded the following results:
1) The degree hours of frost on the ice surface to freeze a water sheet decreases exponentially with wind velocity at the ice surface.
2) The 1.5m-height outdoor temperature and the 3m-height wind velocity yields a similar relationship between wind velocity and degree hours of frost necessary for freezing a, water sheet.
3) The overall heat transfer coefficient increases with outdoor wind velocity, mainly because the convection heat transfer coefficient increases with wind velocity. Changes in nocturnal radiation due to cloud cover accounts for about 10% of the variation in overall heat transfer.
4) A factor evaluating coldness (Fe) considering the contribution of wind velocity (V) on the ice formation is expressed by Fe=2.370V^0.288. A temperature-wind integrated number, TWIN, is defined by multiplying the degree hours of frost by Fe. The TWIN value required for freezing a unit thickness of water is 8.6K·h·mm^-1.
5) The computer program for automatically controlling spray intervals during ice making operates in two modes. The ice-making mode is usually employed and the time to complete freezing of a water sheet is estimated with TWIN, to trigger the following water application. During snow falls the program changes to the snow-melting mode and snow is melted by the water spray to form slush, and the following water application takes place after the TWIN necessary for freezing the equivalent thickness of sprinkled water is reached.
6) This program controls water spray intervals in ice-pond ice-making systems according to outdoor temperature and wind velocity, and results in effective ice production.

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Lettuce seedlings of cv. “Okayama” were water cultured in a growth chamber for 24 hours of 12 hours day and night in order to study the effect of light quality on the absorption of water and minerals. Artificial lighting was done by lamps of white, red, yellow, green and blue colors. Light intensities were controlled to three levels of 250, 125 and 62.5μmol·m^-2·s^-1 in PPFD for each color and the amount of water and minerals absorbed by plants were measured at the end of 24 hours of treatments. The effect of light quality on the content of minerals in saps and dried leaves were also studied after 15 days of cultivation under artificial lighting of 250μmol·m^-2·s^-1
1) Larger amounts of water and minerals were absorbed by plants under high light intensity compared with middle or low light intensity. Ca absorption was most strongly affected by the light intensity. Absorption of P, however, was less affected. Effects of light intensity on the absorption of water and minerals were rather clear under white and green lights compared with under yellow and red.
2) Effects of light quality on the absorption of water and minerals were generally clear under high light intensity. The amount of absorbed water was larger under white and blue light and decreased as following order, green, red, yellow color. The amount of water absorbed under yellow light was lowest and 70% of that under white. Minerals absorption generally showed the same tendency as that of water absorption generally showed the same tendency as that of water absorption and was higher under white and blue lights but lower under yellow light.
3) Sap nitrate concentration was most strongly affected with light quality and was higher under white and blue lights and lower under yellow light. On the contrary, sap K concentration was little affected with light quality. Calcium and magnesium concentration in the sap extracted from mid-rib showed similar tendency to the absorption of water and minerals, and were higher under white and blue but lower under yellow color. However, those elements extracted from leaf lamina of inner or outer leaves was higher under red light. Sap P concentration was significantly higher under blue light.

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For Japanese agriculture, various methods of cost reduction in rice production are investigated. On the other hand, consumers require the high quality and tasty rice. We then considered the optimum condition for rice storage in grain silo of country elevator from the viewpoints of energy saving and quality preservation. The paddy storage test of various combinations of moisture content and storage temperature was carried out, and the change of fat acidity value, which is usually used as an index of rice quality, was analyzed introducing the integrated temperature. The following results were obtained.
1) While the storage term is less than one year, the fat acidity value increases linearly with time elapsed. The higher the moisture content is, and the higher the storage temperature is, the faster the increasing rate is. We then described the change of fat acidity value using the integrated temperature during the storage.
2) The optimum standard values for the calculation of integrated temperature were around 10°C for the every levels of paddy moisture content ranging from 12 to 17% (WB). So the standard temperature of integrated temperature was determined as 10°C for the ease of calculation.
3) The equation to estimate the fat acidity value was set up using the integrated temperature and the fat acidity value increasing rate (A) which describes the effect of paddy moisture content.
4) Since the standard temperature is 10°C, the storage temperature of lower than 10°C is useless from the aspect of fat acidity value.
5) The optimum storage temperature can be obtained using the estimating equation according to the paddy moisture content and the tolerance limit of fat acidity value.

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