The mean velocity gradient, G, has been used as a principal design and operation parameter for flocculation unit. This paper questions that significance. The physical and qualitative meaning of collision efficiency factors of each transport mechanism (Brownian motion, fluid shear, and differential sedimentation) are reviewed. The overall collision frequency function is calculated by summing up the collision frequency function of each mechanism. In the collision of two particles of different size, a diagram showing the dominant region in which each mechanism is important is developed and the meaning of the diagram is discussed. The primary ramification of this curvilinear, heterodisperse approach is that G is found to be not nearly so important. Previous experimental work in which the role of G has been examined is reviewed in light of this finding.

A food life style itself is substrative relations with culture, and is concerned with our daily life. Especially a food taboo comes from the intelligence which resulted from an ancestor's life experience. Accordingly, we can say a food taboo began with human appearance, settled in convention of folklore society, and forms it's own boundary todays. Since a practice of a food taboo is combinded firmly with various sociological factors such as religion, custom, and so on, it is very hard to change, even though the belife of a food taboo is not true. According to the result, first, significant factors effecting on a practice of a food taboo was a level of age, a level of education, religion, family pattern, behavior of subject and her mother for food life management, education of subject and her mother, and religion of subject and her mother. Second, in analysis of factors according to classification of food taboo a practice of a food taboo which classified to food of animal, food of plant and the other food showed significant differences, comparing religion of subject with her mother. Third, a result examined practice frequency and review of science, non science indicated that foods such as Egg of Globefish, Lettuce, Coffee, Persimmon, dried Persimmon, Soybean and Sugar are tabooed on the basis of science, and foods such as Vinegary food, Thieved food, Soup of Tangle and Dogmeat tabooed on the basis of non science. But in the case of Puja, it's basis of science is not identified. These food taboos are tabooed by more then 50% of subjects including who answerd 'there is some case to practice it' Therefore, we should continue analysis of science for the reason of a food taboo, at the same time, provide the origin and try to have a rational food life.

엽위별로 형성된 병반수나 병반면적율은 통일계품종에 있어서는 n-1에서 n-3까지 그리고 일본형수수품종에 있어서는 n-2에서 많았으나 통일계품종중에서도 고도로 감수성인 노풍에 있어서는 n-1(지엽)에 가장 많이 분포되어 있었다. 병반의 분포도와 시비수준과의 관계는 시비수준이 높아질수록 뚜렸하게 나타나는 경향을 보여주고 있다. 엽위별로 보면 수잉기 이후 이삭도열병의 전염원으로는 n-1에서 n-5까지의 잎위의 병반이 관여하나 주로 n-1엽과 n-2엽의 관여도가 큰 것으로 고찰되었다. 수잉기 이후의 저온역에서의 변온은 잎위의 병반에서의 포자 형성량을 증가시키며 포자의 형성, 이탈, 비산에 아무런 지장을 주지않고 9월말까지도 다량의 전염원을 수에 공급하고 있었다.