• Journal of The Korean Association For Science Education
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• v.22 no.4
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• pp.717-724
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• 2002

In this study. the effects of grouping by students' agreeableness in cooperative learning strategy applied to middle school science classes on their achievement. confidence, satisfaction, attitude toward science class, and cohesion of group members were investigated. One hundred and fifty-eight students were assigned to control group, homogeneous group and heterogeneous group, and taught about separation of mixture for 7 class hours. The results revealed that there was no significant difference in the achievement test scores. However, significant interaction between the instruction and the level of agreeableness were found in the satisfaction and the cohesion of group members. Students of higher agreeableness level in the homogeneous group were more satisfied with science class and cohesive. Students' attitude toward science class in the homogeneous group was also significantly higher than those in the other groups.

• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.149-155
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• 2011

This paper presents simulations of advance evacuation analysis using a cellular automata model for passenger behavior in an emergency of passenger ship. The proposed cellular automata model divides the space in a uniform grid called "cell." Each passenger is located in a cell and moves to another cell according to a set of local rules assumed to be associated with the individual and crowd behaviors of the passengers. To verify the usefulness of the proposed cellular automata model, 11 tests, all of which are specified in International Maritime Organization Maritime Safety Committee/ Circulation 1238 (IMO MSC/Circ. 1238), were implemented, and it was confirmed that all the requirements of these tests had been met.

• Journal of Science Education
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• v.33 no.1
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• pp.1-11
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• 2009

The purpose of this study was to investigate how the argumentations were affected by the students' characteristics in the small groups. The level of self-concept and science related attitude were examined to the eleventh grade high school students in Daejeon city, and the twelve students were participated for this study. The participants were divided into homogeneous groups and heterogeneous groups. The argumentations under the condition of the interpretations about the experimental results in each small group were recorded by VCR. The recorded data were transcribed, then argumentation levels from transcripts in each small group were analyzed through Mitchell's parameters of argumentation. The results of this study were that the group which had higher level of both self-concept and science related attitudes achieved higher level of argumentation. Therefore, it is necessary for teachers to induce students to ask questions and present activities appropriately in order for those who have low self concept and science related attitudes to participate in argumentation.

• Environmental and Resource Economics Review
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• v.27 no.4
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• pp.695-723
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• 2018

Recently, extreme weather due to climate change has become more frequent, and increase of fine dust has worsen air quality in Korea. Therefore, not only negative perception on coal-fired power generation is dominant, but also the social acceptance of nuclear power generation declines. This study aims at deriving consumer preferences on the mid and long term power mix with various energy sources. Willingness to pay for each generation source was estimated and the preference heterogeneity of consumers was examined by using mixed logit and latent class models. Mixed logit estimation results show that the preference heterogeneity of consumers is especially large for the nuclear power relative to renewable or coal energy. According to the estimation results from the latent class model, group 1 prefers renewable energy while group 2 prefers coal energy. Group 3 shows lexicographic preference which means restricted rationality. As for the policy implication, it is necessary to understand the preference heterogeneity of consumer groups in planning the mid to long term power mix.

• 한국노년학
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• v.30 no.3
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• pp.683-694
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• 2010

This study was to investigate the effects of aquarobics exercise on body composition, fitness and health related quality of life (sf-36) in elderly women and to provide basic data to exercise prescription. The subjects were the 60~70 years old seniors who participated in exercise program at health promotion center and had been divided into exercise(N=25) and control(N=30) group, respectively. Aquarobics exercise was performed twice per week for 8 weeks at 40~70% heart rate reserve(exercise intensity) and body composition, fitness and SF-36 were measured before and after exercise. In body composition, there were significance in weight(p=0.044), body mass index(p=0.038), and %fat(p=0.005) between groups before and after. In fitness, there were no significance in fitness such as chair stand, and chair sit and reach, but there were significance in 2-minute step(p<0.001), arm curl(p=0.005), back scratch(p=0.023), and 8-ft up and go(p<0.001) between groups. In SF-36, there were no significance in physical functioning, role limitation-physical, role limitation-emotional, social functioning, mental health, and vitality, but there were significance in bodily pain(p=0.039), and general health(p=0.024) between groups. It was found that aquarobics exercise was one of the good exercise types for the elderly to improve body composition and fitness. Also, there was positive effect on health-related quality of life partially.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.10a
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• pp.396-399
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• 2004

어떤 집단에서든 그 구성원의 효율적인 관리가 무엇보다 중요하다. 이러한 효율적인 관리는 집단의 구성원이 많을수록 한 개인이 방대한 자료를 분석 및 관리하기에는 많은 어려움이 있다. 본 논문에서는 이 많은 자료를 바탕으로 퍼지 추론을 이용하여 근태 관리 시스템을 개발하였다. 먼저 퍼지입력 변수로는 출입구에 미리 설치되어 있는 지문 도어락과 관리실의 PC를 통해 사원들의 출퇴근 시간과 월별 근무시간, 월별 근무일수, 월별 조퇴 및 지각일수를 산출한 후 월별 휴가일수를 입력한다. 이 입력 데이터 값으로 퍼지 연산을 수행 후 구성원 개개인의 월별 성실도를 결정하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.33-36
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• 2006

OR 기법이 현실에 성공적으로 적용된 분야 중 하나가 차량 경로 문제 풀이며 이 분야에 대한 연구는 꾸준히 진행되어 오고 있다. 시간대 제약이 있는 차량 수 배송 문제는 기존의 차량 배송 문제에서 더욱 진보된 형태의 문제이다. 많은 연구가 있어왔지만, 이러한 형태의 문제들은 NP-hard 형태의 문제이므로 meta-heuristic 기법들이 많이 사용되었다. 유전자 알고리즘에 비해 타부 서치 기법이 많이 사용되었는데, 이는 시간대 제약이 있는 차량 수 배송 문제의 경우 유전자 알고리즘의 근간인 염색체 형태로 표현하기가 쉽지 않기 때문이다. 이에 본 논문에서는 시간대 제약이 있는 차량 수 배송 문제를 다수의 차량을 사용하는 Grouping Genetic Algorithms을 적용하여 이러한 어려움을 해결하였다. 또한, 기존의 유전자 알고리즘들은 초기 해 집단을 임의 선택 방식으로 구성하였지만, 초기 해 집단 구성을 heuristic 기법을 사용하여 적합도 함수 값이 좋은 해들로 구성하여 기존에 사용된 알고리즘들과 성능을 비교 분석하고자 한다.

• Journal of The Korean Association For Science Education
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• v.39 no.5
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• pp.625-635
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• 2019

Students are exposed to many visual representations in various visual cultures. Infographics combining visual representations and writing can effectively convey information. Also it can be efficient ways for teachers to focus on important contents. Students can use infographics as a method directly to organize information. Therefore, the infographics that students use both writings and images directly and visually will be more effective on elementary school science classes than the workbook. Classes are guided with the same scientific inquiry and experiment written on the science textbook. The experimental group students organized scientific inquiry by infographics, while the comparison group students still used the workbook. First, the types of infographics are determined by what students want to explain. Based on learning objectives, students used the right type of infographics to effectively convey their focus on information. Second, the infographics organizing activities used in the classes had a significant effect on students' academic achievement. Also, the infographics organizing classes are positively associated to science-related attitudes, including such+ as 'Leisure Interest in Science', 'Adoption of Scientific Attitudes', and 'Attitude to Scientific Inquiry'. Third, visual tendency and classroom treatments had no interactions, but the experimental group had a positive impact regardless of student's characteristics. Fourth, experimental group showed positive attitudes toward to students' perception of infographics. Since some of students had difficulties organizing information in infographics, further research is required to enable students to reduce their burden in application of infographics.

• Korean Journal of Ichthyology
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• v.22 no.1
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• pp.56-60
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• 2010

The Cobitis hankugensis-Iksookimia longicorpa complex from Korea has been presumed to be a unisexual lineage, originating from C. hankugensis and I. longicorpa and having almost all females. Recently, it was confirmed that the complex consisted of one diploid and two triploid complexes. From observation of their oocyte envelopes, three forms could be classified: a villous projection in I. longicorpa, a granular one in C. hankugensis and two triploid complexes, and a granule with villous one in the diploid complex. Even within the same granular projection, they showed specific features in length and density number from each other. These architectures are first observed in cobitid complexes and may playa role in identification of diploids and triploids.

• KIISE Transactions on Computing Practices
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• v.21 no.1
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• pp.40-45
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• 2015

Online social networks(OSN) are very popular nowadays. As OSNs grows, the commercial markets are expanding their social commerce by applying Influence Maximization. However, in reality, there exist more than two players(e.g., commercial companies or service providers) in this same market sector. To address the Influence Maximization problem between adversaries, we first introduced Influence Maximization against the social adversaries' problem. Then, we proposed an algorithm that could efficiently solve the problem efficiently by utilizing social network properties such as Betweenness Centrality, Clustering Coefficient, Local Bridge and Ties and Triadic Closure. Moreover, our algorithm performed orders of magnitudes better than the existing Greedy hill climbing algorithm.