웹기반 협력 학습을 위한 멀티에이전트간의 통신에 관한 연구

이철환,한선관,Lee, Chul-Hwan,Han, Sun-Gwan 한국정보교육학회 2000 정보교육학회논문지 Vol.3 No.2

본 연구는 웹 기반 협력학습을 위한 시스템에서 학습자의 학습을 돕기 위한 멀티에이전트간의 통신에 관한 연구이다. 우선, 에이전트 시스템에 대한 전반적인 내용과 특정을 고찰하였고 에이전트 상호간의 통신인 KQML에 대하여 살펴보았다. 또한 협력학습을 위한 에이전트 기반의 시스템 구조와 에이전트간의 상호 통신 방법을 제시하였다. Java 언어를 이용하여 협력학습 시스템을 설계 구현하였으며 실험을 통하여 에이전트간의 통신에 의한 협력학습 시스템의 효율성을 고찰하였다. The purpose of the paper is communication between multi-agents for student's learning at web based collaborative learning. First, this study investigated the whole contents and characteristics of an agent system and discussed KQML, communication language between multi-agents. Also, we suggested architecture of an agent based system for collaborative learning and interaction method between agents using KQML. We design어 and implemented collaborative learning system using Java programming language, and we also demonstrate the efficiency of collaborative learning system by communication between multi-agents through experiments.

연초 III형 Grey엽의 발생양상과 화학성분 특성

이철환,진정의,한철수,Lee, Chul-Hwan,Jin, Jeong-Eui,Han, Chul-Soo 한국연초학회 1996 한국연초학회지 Vol.18 No.2

The occurrence and chemical properties of grey tobacco leaves (Type III) found in 1995 crop of flue-cured tobacco cultivated in paddy field were investigated to compare with those of normal leaves. Cured leaves of NC82 were separated by visual characters into 3 classes of slight, fair and severe symptoms of grey leaf by the percentage of grey parts to whole leaf area. Number of samples classified with discoloring portion was the order of greyish brown > reddish brown > greyish yellow, respectively. Grey leaves of this type were mostly found among the leaves harvested from upper stalk position, and it was estimated that growth rate of upper leaves also influenced on the occurrence of grey leaves. Grey leaves showed remarkably lower b* and L* values than those of normal leaves, while a* value was mostly higher in grey leaves. These tendencies in chromatic aberration showed more remarkable difference in the degree of grey symptoms. Chemical analyses of grey leaf samples indicated that they contained less total nitrogen and nicotine, and more total sugar and starch than those of normal leaves. In chemical traits, these tendencies were accordance with the degree of grey symptoms, and within the same leaf, grey parts were decreased in total nitrogen and ether extract content compared with those of normal parts, but there was no difference in nicotine and Cl contents. Key words : grey leaf tobacco (type III), grey symptom, color, chemical properties.

연초 수확엽의 숙도가 색채 및 색소물질 함량에 미치는 영향

이철환,진정의,한철수,Lee, Chul-Hwan,Jin, Jeong-Eui,Han, Chul-Soo 한국연초학회 1996 한국연초학회지 Vol.18 No.1

Field experiment was conducted to get the basic information about the difference in color and plastid pigments at the different stage of harvest of flue-cured tobacco cultivated in paddy field, and compared to upland ones. All tested crops were primed in lots of 3 to 4 at each priming, beginning at the bottom of the plant. Leaf pigments and chromatic values of tobacco leaves were determined in samples collected at weekly intervals, and according to analyses obtained from 4 stalk positions. By the degree of maturity, leaves harvested were separated with visual characters into four classes of immature, mature, ripe and mellow. regardless of stalk position, chlorophyll contents was higher in the order of immature > mature > ripe > mellow, respectively. In fresh leaves, chlorophyll levels was higher with ascending stalk position. chlorophyll a and b in cured leaves were less than 10% of the amount present at harvest, and it was estimated that maturity condition also influenced the rates of degradation of plastid pigments. Fully mature leaves of upland diverted from paddy field showed slightly higher in chlorophyll contents than in those of upland tobacco ones but somewhat lowered in $L^*$ and $b^*$ values, and there was no difference in $a^*$ value.

토양산도 및 시비량 조절에 의한 연초의 Grey엽 발생방지 효과

이철환,진정의,이동훈,Lee, Chul-Hwan,Jin, Jeong-Eui,Lee, Dong-Hoon 한국연초학회 1994 한국연초학회지 Vol.16 No.2

This study was carried out to get agronomic information about the tobacco culture in paddy soil where incidence of grey tobacco leaves used to appearly uptake of iron, manganese and chlorine due to soil acidity and high water level. Application of lime to paddy soil(pH5.4-5.6) reduced content of iron, manganese known as proceeding materials giving rise to variegated grey tobacco after curing, compared with non-treatment. Grey leaves were found mainly at lower and middle stalk positions, and incidence of grey tobacco was lowered by application of lime in the well drained field but was not affected by level of fertilizer application. Amendment of soil acidity by lime tended to decrease chlorine and manganese content in leaves. Nicotine and mangenese content of leaves were lowered by reduction of one-quarter fertilizer level. In case of lime treatment, increase of yield reached to 4-6% comparing with those of non-treatment but price per kg was not affected. Reduction of N fertilizer level to three-quarters had the equal yield but high quality of leaf comparing with standard fertilization in paddy field.

황색종 cyclic 건조엽의 화학성분 특성

이철환,진정의,한철수,Lee, Chul-Hwan,Jin, Jeong-Eui,Han, Chul-Soo 한국연초학회 1998 한국연초학회지 Vol.20 No.1

The bulk curing experiment to the improve the quality of flue-cured leaves were carried out to evaluate relationship between cyclic curing and conventional curing method. We studied the effect of the cyclic change of wet bulb temperature at the yellowing stage of flue curing on chemical properties of cured leaves. The wet bulb temperature was automatically controlled between preset high($38^{\circ}C$) and low point ($35^{\circ}C$) everyone hour cyclically during 12 hours after starting luring. As a result, the acceleration of the increase in the chemical properties of cured leaves were observed. As to the chemical properties, there was decreased in citric acid, increased in malic acid of the nonvolatile organic acids and all higher fatty acids content of leaves cured by this method compared with in that of conventional curing method, while a major chemical compounds in relation to aromatic essence of cigarette smoke in essential oil components of lured leaves was mostly higher in this method than those of conventional ones, and it was evaluated that there was decreased in CO, TPM, Tar, and $CO_2$ content of the cigarette smoke comparing to the conventional luring method.

사료작물 윤작재배에 의한 연초포지의 제염효과

이철환,진정의,한철수,Lee, Chul-Hwan,Jin, Jeong-Eui,Han, Chul-Soo 한국연초학회 1997 한국연초학회지 Vol.19 No.1

The field experiment for field desalinization by precultivation of orchard crops were carried out to evaluate relationship between the varieation of chlorine contents of soil and crop uptake in the upland diverted from paddy field. After harvest of grass crops, soil samples were taken for analysis of chlorine contents of soil layers. Regardless of kinds of grass crops cutivated, contents of soil chlorine were decreased comparing to non-crop plot. Chlorine content in plant harvested at just before the flowering stage was much higher than that of after flowering. Chlorine uptake and dry matter were increased in order of Italian ryegrass, Perennial ryegrass, and Sudan grass. Positive correlations were showed between chlorine uptake and dry matter. The content of soil chlorine decreased by higher yield of dry matter.

황색종 연초 황변기 cyclic건조가 건조엽의 물리성에 미치는 영향

이철환,진정의,한철수,Lee, Chul-Hwan,Jin, Jeong-Eui,Han, Chul-Soo 한국연초학회 1998 한국연초학회지 Vol.20 No.1

In the flue curing process, the wet bulb temperature is usually controlled at a constant level. To improve the quality of flue cured leaves, we studied the effect of the cyclic change of wet bulb temperature at the yellowing stage of flue curing on physical properties of cured leaves. The wet bulb temperature was automatically controlled between preset high (38℃) and low point (35℃) every one hour cyclically. As a result, the acceleration of the increase in the physical properties of cured leaves were observed. The leaves cured by this method were more or less orange in color, better bodied, and less brittle compared with the leaves produced by conventional curing. However, the leaves cured by this method had a little sharpness and harshness. As to the physical properties, there was decreased in occurrence of flat leaves than that of conventional ones. On the other hand, in case of cyclic curing method, increase of price per kg reached to 2-3% compared with those of conventional ones.

홀리스틱교육관점에서 바라본 가상교육의 방향

이철환(Lee, Chul-Hwan) 한국홀리스틱융합교육학회 2000 홀리스틱융합교육연구 Vol.4 No.1

Education is undergoing rapid and dramatic changes. Technology help to meet the learning needs of diverse population. The need for lifelong learning is growing as specific skills become obsolete and new ones are needed. Distance Education programs are increasingly used for lifelong learning. The purpose of the paper is to investigate the concept and nature of knowledge and Homo-Knowledgian, positive aspects as well as negative aspects of information technology, new paradigm of education in information society, and the status and future direction of virtual education in the viewpoint of holistic education.

SCOPE 모델 기반 상호운용성 평가방법에 관한 연구

이철환(Lee Chul Hwan),이태공(Lee Tae Gong) 한국정보과학회 2012 한국정보과학회 학술발표논문집 Vol.39 No.1B

지금까지 발표된 상호운용성 측정모델은 점대점(Point-to-Point)으로 단위시스템간 상호운용성을 평가하는 모델부터 네트워크중심(Network-Centric)의 복합시스템(System of Systems)간 상호운용성을 평가하는 모델까지 여러 모델들이 있다. 그중 SCOPE 모델은 네트워크중심의 복합시스템간 상호운용성을 평가하기 위한 모델이고, NCAT은 SCOPE기반의 상호운용성 평가 도구이다. 본 논문은 SCOPE를 기반으로 NCAT의 상호운용성 평가 방법과 다른 상호운용성 평가 방법론을 제시한다. 제시된 방법론은 SCOPE 모델을 기반으로 복합시스템의 상호운용성을 평가 할 때 서비스별 우선순위를 부여하지 않은 기존 방법과 달리 우선순위를 부여한 방법이다.

경계의무 위반의 원인비율 배분 기여 정도에 관한 연구

이철환(Chul-Hwan Lee) 한국해양교통학회 2022 Journal of Korean Association of Maritime Transpor Vol.1 No.1

해양사고의 예방을 위해서는 이미 발생한 사고에서 얻은 교훈으로부터 재발 방지 방안을수립하는 것이 중요하며, 그 방안 중 하나가 중요 의무 위반행위, 또는 지속·반복적 발생 의무 위반행위에 대하여 좀 더 중한 책임을 부과함으로써 예방효과를 높일 수 있다 할 것이나우리 해양안전심판원의 재결에 있어서 원인제공 비율 정도를 배분할 때 경계의무 위반행위에대한 기여 정도가 다소 낮게 인정되는 것으로 보이는 바, 중앙해양안전심판원의 재결서 상충돌사고에 대한 양 선박의 사고 발생에 대한 원인제공 정도 배분을 검토하여 해양사고 예방에 있어서 현행의 경계 의무의 중요성에 대한 판단 정도를 검토하여 개선점을 살펴보고자 한다. For the prevention of marine accidents, it is important to establish measures to prevent recurrence based on lessons learned from accidents that have already occurred, and one of the measures is to impose greater responsibility for violations of important obligations or continuous and repeated violations of obligations. Although it can be said that the effect can be increased, the degree of contribution to the violation of the duty of vigilance seems to be recognized as somewhat low when allocating the degree of cause-giving ratio in the decision of the Korea Maritime Safety Tribunal. The purpose of this study is to examine the points for improvement by examining the distribution of the degree of contribution of causes to the occurrence of accidents on both ships, and by examining the degree of judgment on the importance of the current vigilance duty in the prevention of marine accidents.