Stalls of three different lengths 160, 170 and 180cm with width being 130cm in each case were used for an experiment. Each was provided with a urine-feces mixed type gutter with a slotted cover.
Six milking cows (Holstein) varying in body size were kept in each of these stalls for three days observation with regard to cleanliness of cows udder and time required for udder preparation.
Dirtiness of the udder and udder preparation time increase with decreasing cow body weight when the stall length was fixed, and with stall length when cow body size was fixed. The results indicated that stall length should be 1.3cm longer for every additional 10kg cow body weight when the udder preparation time was fixed. This value is much more than that published standard dairy barn construction which bases at all length on cow body weight.
Standard values should thus be redetermined so that udder preparation time will be uniform and this in turn may lead to greater routine work efficiency.

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Advantages of up-flow Biomass gasifier (with CO gas as main combustible material) over down-flow type are lower output gas temperature, lower solid tar and dust contained in output gas, and no plugging problems in the system. In this study, the suitable control conditions of up-flow gasifier for rice husk were investigated by simulation method, and correlated the data with previous experimental results. Based on the results of simulation, the best performance condition for generating more power and energy was obtained when supplying air containing 174.1% of dry material weight and water containing 6.5% of dry material weight to the combustion layer. Under this condition, the optimum output gas temperature was 150°C, and the output gas calorific value from the gasifier was 4765kJ/m³(at 30°C, 1atm). In addition, a calorific value of 17765kJ/kg for liquid tar containing 33.2% material weight was also generated from the gasifier at the same condition.

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A horizontal compartment type plug flow anaerobic digester was installed next to a stanchion barn and operated with dairy slurry of about 9.59%total solids (TS) at 42.5°C. The loading rate was kept at about 7.6g volatile solids (VS)/(l·d). Two feeding methods (one-time feeding, 400l×1 time per day; multiple feeding, 100l×4 times per day) were compared under a retention time of 10 days. There were no significant differences between the two methods in the amount of biogas produced but a significant difference was recognized in the methane content. In the case of multiple feeding, the methane content of the biogas produced remained high and constant. During the experiment, the mean values of total and net production were 1.9l/(l digester·d) and 1.1l/(l digester·d), respectively, at an ambient air temperature of 18°C. The biogas was used to heat the digester and surplus biogas was used for supplying hot water.

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It is necessary to take thermal properties into account in designing a methane fermentor system. Therefore, the thermal properties of a two-phase anaerobic fermentor being used as a pilot scale fermentor were evaluated by heat balance analysis.
The results obtained are as follows; The apparent over-all heat transfer coefficients of the acid fermentor and the methane fermentor were 1.41 and 2.08kcal/(m²·h·°C), respectively. The film heat transfer coefficients of the inner walls of the fermentors were 29.83 and 28.75kcal/(m²·h·°C), respectively. The ratio of thermal loss to the supplied heat capacity of each fermentor was also evaluated. In winter, the thermal loss from the fermentors themselves was the greatest, 35.6%, and in summer the loss from the hot water piping was the greatest, 34.9%.

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Three treatments of bedding 4kg, 2kg and 0kg head/day of sawdust were carried out to clarify the effects of bedding on stall and udder cleanliness, and udder operaration time.
Three milking cows of various body weights were confined in stanchion stalls provided with a urine-feces mixes type gutter with a slotted steel cover. Floor length of each stall was adjusted to each cow body size based on the result of a previous study.
A half amount of sawdust (i. e. 2kg, 1kg and no use) was provided following stall floor cleaning conducted morning and evening each day.
Observations on (1) the manure spreaded area on stall floor, (2) solid matter on udder and (3) time required to wash the udder before milking were made every morning and evening for 6 days in succession, then repeated twice so that the total period of observation was 18 days.
The first two operations were made immediately before stall floor cleaning. All three operations were conducted by the same woker throughout the experimental period.
Remarkable differeces were found for using and not using bedding and morning and evening observations. In geneal, the more bedding was use, the greater was the effect on floor reduction and udders were dirty. However, morning observastions indicated no significant differences in stall floor dirtiness for bedding using 4 or 2kg of sowdust. Morning and evening observations showed significant differences in udder dirtiness for bedding using 4kg and 0kg. The time required for udder washing for bedding using 2kg and 0kg was essentially the same only at evening opereations.
It is clearly evident from the above that 4kg of sawdust for bedding per head, per day results in greater cleanliness of the stall floor and cow udders, and lesser time required for washing udders than 2kg for bedding. But to lessen the amount of sawdust without undesirable effect, 1kg and 2kg of sawdust for evening and morning, respectively, totaling 3kg per day, appears to give results as good as when using 4kg per day.

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This study was carried out for the purpose of understanding the microwave drying characteristics of paddy rice, especially the conditions of cracked kernels after microwave drying. Experiments were conducted using microwave heating on pseudo-fluidized bed drying by employing the batch-type intermittent drying method.
As a result, microwave drying method can increase the drying rate potential by approximately ten times or more than the ordinary heated air drying method. In addition, microwave drying on pseudo-fluidized bed can increase the drying rate per net radiation time by 10-20% and decrease the cracked kernels by 5-9% than on stationary bed.
During the drying process, the moisture content was decreased by about 30-40% during the radiation period and by about 60-70% during the post radiation period. When paddy rice was dried at high kernel temperature, the cracked kernels were reduced by sufficiently setting the kernels to achive the complete post radiation period.

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