Transport rate of windblown dusts such as soil, sand, snow is proportionate to U_*^3 and U_*, friction velocity, approximately to flow velocity of wind. Therefore, through measurement and the flow velocity of wind, it turned out that,considering different velocity distributions caused by downstream distance and porosity percent,windbreaks with appropriate porosity rate to the protection area should be chosen for the optimal fence effect. In the economic respect, better are fences with gap of 20%∼30%. Among the windbreaks to have the optimal fence effect.

콩의 생식생장기인 착협시(R3)에 상부 50%와 하부 50％로 구분하여 엽제거 및 엽-협제거처리 하여 줄기, 엽 및 종실건물중과 가용성 당, 전분 및 단백질함량에 미치는 영향을 구명하기 위하여 1990년과 1991년에 고려대학교 자연자원대학 덕소 농장에 팔달콩, 백운콩 및 단엽콩을 공시하여 실시한 시험결과를 요약하면 다음과 같다. 1. 팔달콩, 백운콩 및 단엽콩 모두 건물축적과 가용성 당, 전분 및 단백질함량에 처리간 같은 경향을 보였다. 2. 평균 줄기건물중은 상엽-하협제거와 하엽-상협제거로 높았고 상엽제거와 하엽제거는 낮았다. 3. 엽건물중은 처리중에서 상부엽이 높은 경향을 나타냈다. 4. 종실수와 종실건물중은 엽 및 엽-협제거로 감소되었으나 하엽제거와 하엽-상협제거의 하부에서 높았다. 5. 가용성 당과 전분함량도 처리중에서 하부종실에서 높은 경향이었다. 6. 단백질함량은 상엽제거의 상부와 하엽제거의 하부에 감소되었으나 하엽제거의 상부종실에서 가장 높았다.

발아의 신속성과 균일성을 높이기 위하여 벼, 보리, 콩 종자에 대하여 몇가지 화학물질처리와 종자의 흡습건조처리를 통하여 종자퇴화지연효과를 검토하였다. 처리한 생장촉진제 및 노화지연제간에 경미한 차이는 있었으나 GA3 가 벼의 발아율을 높인것 외에는 뚜렷한 종자세 개선의 효과를 보이지 않았다. 노화종자를 PEG용액에 흡습건조처리할 경우 용액농도가 높을수록 평균발아일수가 길어지고 발아율이 낮아지는 경향이나 발아율 유지의 효과나 발아균일성향상의 효과는 없었다. 저온, 과습 및 삼투조건 등 불량한 환경에 대한 발아반응도 미미하였다. 어느 처리도 종자세 개선에 뚜렷한 효과를 보이지는 않았으나 GA3 처리가 전체적으로 발아반응이 그 중 좋은 편이었다.

Since L.A. Zadeh introduced the theory of fuzzy sets in 1965, E.H. Mamdani applied the theory to the steam engine control in 1974. Since then, scientists have shown a great deal of interests in its application to practical problems and the possibility of the application of the theory a more complicate system has been increasing greatly. In the fuzzy control, the qualitative knowledge and intuition that the operators of a system has acquired through their experience can be logically described by the Linguistic Control Rule(LCR). The algorithm of th control is made of the LCR, and th control of an object is performed by processing this algorithm implementing a computer. in this thesis, the fuzzy controller of the ship's steering system is devided into two systems, namely FC1 and FC2, according to their control function. FC1 is for the course keeping steering, wheress FC2 is for the altering of s ship's course. The characteristics of the control system were investigated through the digital computer simulation and the results were compared with those of the conventional steering system. It was found that the fuzzy control was more efficient than the conventional auto pilot system.

Many studies have been done in the field of fuzzy logic theory, but it's application is not so much, and particularly, there isn't any application to the ship's steering system, until now. This paper is to survey the effect of application of fuzzy logic control to the ship's steering system. The controller is made up of a set of Linguistic Control Rules which are conditional linguistic statements connecting the inputs and the output, and take the inputs derived from the errors, that is, deviation angle and it's angular velocity. These two variables together give information about the state of the steering system, and the Linguistic Control Rules are implemented on the digital computer. The characteristics of this system were investigated through the computer simulation and satisfactory results compared with that of the conventional PD controller were obtained.