• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.160-169
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• 2003

Pantograph of high speed rolling stock is one of the key components that transfer of associated technologies was blocked fundamentally from advanced nations. In this study, main technologies related to development of prototype pantograph installed on prototype test train developed according to the project "Development of high speed railway technology" are presented. Status of current korean technologies is explained by presenting developed technologies and applications during the past 6 years from concept design to test and evaluation.

• Advances in aircraft and spacecraft science
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• 제2권3호
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• pp.329-343
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• 2015

This study aimed to observe the effect of a novel concept (referred to as the flap extension) implemented on the leading edge of the flap of a three element high lift device. The high lift device, consisting of a flap, main element and slat is designed around an Airbus research profile for sufficient take off and landing performance of a large commercial aircraft. The concept is realised on the profile and numerically optimised to achieve an optimum geometry. Two different optimisation approaches based on Genetic Algorithm optimisations are used: a zero order approach which makes simplifying assumptions to achieve an optimised solution: as well as a direct approach which employs an optimisation in ANSYS DesignXplorer using RANS calculations. Both methods converge to different optimised solutions due to simplifying assumptions. The solution to the zero order optimisation showed a decreased stall angle and decreased maximum lift coefficient against angle of attack due to early stall onset at the flap. The DesignXplorer optimised solution matched that of the baseline solution very closely. The concept was seen to increase lift locally at the flap for both optimisation methods.

• 시스템엔지니어링학술지
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• 제11권2호
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• pp.61-73
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• 2015

The early-phase naval ship design demands requirements synthesis rather than design synthesis, which conducts engineering design for several domains on a detailed level. Requirements synthesis focuses on creating a balanced set of required operational capabilities satisfying user's needs and concept of operations. Requirements are evolved from capability based languages to function based language by statistical exploration and engineering design which are derived in the following order: concept alternative, concept baseline, initial baseline and functional baseline. The early-phase naval ship design process can be divided into three passes: concept definition, concept exploration and concept development. Main activities and outcomes in each pass are shortly presented. Concept definition is the first important step that produces a concept baseline through extensive design space exploration promptly. Design space exploration applies a statistical approach to explore design trends of existing ships and produce feasible design range corresponding to concept alternative. It further helps naval systems engineers and operational researchers by inducing useful responses to user and stakeholders' questions at a sufficient degree of confidence and success in the very early ship design. The focus of this paper is on the flow of design space exploration, and its application to a high-speed patrol craft. The views expressed in this paper are those of the authors, and do not reflect the official policy or rule of the Navy.

• 대한지구과학교육학회지
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• 제6권2호
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• pp.145-151
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• 2013

The aim of this research is clarify the relationship between concept understanding degree about the environment and environmental sensitivity and heighten understanding of environmental education target to pre-service elementary teacher. The subjects of this study are science education intensive course 65 students of B educational university. Concept understanding degree about the environment was separately investigated by 'the definition of environmental education', 'Write The positive concept of the natural environment education and briefly describe.''The negative concept of the natural environment education and briefly describe'. Next clarify the relationship between concept understanding degree about the environment and environmental sensitivity target to pre-service elementary teacher. Based on these results, propose an alternative to cultivate pre-service elementary teacher's knowledge about environmental education. Degree of understanding of the concept environmental education research results are as follows. First, Cognition degree about definition of environmental education of pre-service elementary teacher is correctly recognized generally. Second, They do not think deeply about natural environment when it comes to the positive concept of the natural environment of pre-service elementary teacher. Third, They have only a little interest in natural environment when it comes to the negative concept of the natural environment of pre-service elementary teacher. Correlation research results of degree of understanding of the concept of environmental and environmental sensitivity are as follows. High understanding degree of environmental education is high environmental sensitivity. Heighten environmental sensitivity of pre-service elementary teacher will be sustainable environmental education so education is necessary for environmental Sensitivity training.

• 한국과학교육학회지
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• 제24권5호
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• pp.937-945
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• 2004

이 연구에서는 이미 해결한 단일개념으로만 구성된 복합개념상황에서 학생들의 문제해결력과 정신용량의 관계를 알아보았다. 과학적 개념이나 원리 하나만 알면 풀 수 있는 문제를 단일개념상황으로 정의하였고 단일개념상황을 2개 이상 결합하여 만든 문제를 복합개념상황으로 정의하였다. 청주시 소재 일반계 고등학교 2학년 학생 152명을 대상으로 정신용량에는 유의미한 차이가 나타나지 않았다. 그러나 이미 해결한 단일개념상황들의 결합으로 만들어 전 복합개념상황의 문제해결에 있어서는 정신용량이 작은 집단에서만 실패한 학생들이 나타났으며 문제해결에 실패한 학생들의 정신용량이 문제해결에 성공한 학생들의 정신용량보다 낮았다. 이러한 연구 결과 단일개념상황은 해결할 수 있으면서 이와 관련된 복합개념상황의 해결에 실패한 이유의 하나를 문제해결자의 정신용량이 작기 때문이라고 볼 수 있다.

• 가정과삶의질연구
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• 제26권3호
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• pp.1-14
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• 2008

The purpose of the study was to examine the internet purchase behavior of items and self-assessment according to self-concept of elementary school students. The data were collected from 716 elementary school students by a self-administered questionnaire. Frequencies and means, Cronbach's Alpha, factor analysis, t-test, Pearson's correlation analysis, cross-tabulation analysis, cluster Analysis were conducted by SPSSWIN 12.0. The results from this study were as follows; First, from self-concept measurements, 4 factors(affective, social, schooling, Family self-concept) were extracted through factor analysis. Second, the subjects were classified into 3 clusters as self-concept types(high self-concept, middle self-concept, low self-concept) through cluster analysis. Third, the significant variables affecting internet purchase behaviors of items included grade, allowance, rank in class, the number of hours on the internet. As the self-concept gets higher, the frequence of the impulsive purchase and imitation purchases gets lower. In the contrary, as the self-concept gets higher, the self-assessment on the impulse purchases and imitation purchases also gets higher. In combination, these results suggest that irrational purchase behaviors were protected by positive self-concept, therefore it is important that children have positive a self-concept.

• 한국과학교육학회지
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• 제17권3호
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• pp.333-343
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• 1997

The purpose of the present study was to investigate an appropriate instructional model in order to remedy students' misconception. As hypotheses of this study, three instructional models, cognitive conflicting, hypothesis testing, and learning cycle models, on biological 'osmosis' concept were tested in 176 high school students. Results of the present study are as follows: 1. All groups used one of three instructional models showed a statistically significant improvement in conceptual change on the 'osmosis' concept between before and after the instruction. In addition, the three hypothesized instructional models were more effective in conceptual change than a traditional expository instruction. 2. There was a statistically significant difference among three experimental groups. Cognitive conflicting model and hypothesis testing model was more effective than learning cycle models. 3. An interviewing after instruction showed that students who had scientific concept on the 'osmosis' through the instruction could effectively apply the concept to other context more than students who had no scientific concept through instruction. The present study indicated that instructional model play an important role on students' conceptual change in science classroom. According to the result of this study, the instruction emphasizing students' active participation in class and scientific reasoning process is more appropriate to remedy misconception that the instruction using students' passive participation in class and expository teaching procedure. This study also indicated that students' concept acquired through instruction is one of important factors to apply it to other context.

• 한국과학교육학회지
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• 제24권2호
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• pp.246-257
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• 2004

본 연구에서는 소화 개념을 주제로 고등학생들의 개념 분화 유형이 어떤 것이 있으며, 이 개념 분화 유형의 각각의 특징은 무엇인지 알아보고자 하였다. 이를 위하여 124명의 고등학생들이 수업 전후에 개념도를 작성하였고, 이 중 19명을 표집하여 인터뷰, 간단한 쪽지 시험을 실시하였다. 학생들이 작성한 개념도, 인터뷰 내용, 쪽지시혐의 결과는 학생들의 개념 분화 유형을 추출하기 위해 분석되었다. 소화 개념에서 개념 분화 유형은 3가지로 구분되었는데, 첫째 유형은 나열형이라고 할 수 있다. 이 유형에 속하는 학생들은 개념도의 작성에서 개념보다는 사례들을 많이 제시하고 있으며, 개념들 사이의 위계 관계가 분명하지 않고, 개념들 사이의 관계성을 파악하는 데 어려움을 보였다. 두 번째 유형은 순서형이라고 부를 수 있는데 이 학생들은 학습의 순서에 따라 개념도를 작성하는 특징을 보였으며, 위계형보다 덜 조직화된 개념도를 작성하였다. 세 번째 유형은 개념의 위계에 따라 개념도를 작성하는데 위계형이라고 할 수 있으며 위계 형성의 정도는 차이가 많았다. 이들 세 가지 유형에 속하는 학생들은 수업 후에 모두 개념도를 보다 정교화 시켰으며, 순서형은 순서형과 위계형이 혼합된 유형 또는 나열형과 순서형이 혼합된 유형으로 바뀌는 사례가 많았으나 다른 유형에 속한 학생들은 개념 유형이 거의 변화되지 않았다. 이러한 연구 결과를 비춰볼 때 나열형에 속하는 학생들이 순서형이나 위계형으로 전환할 수 있도록 도와줄 수 있는 도구들과 효과적인 수업 전략의 개발이 필요하리라고 본다.

• 보건교육건강증진학회지
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• 제3권1호
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• pp.43-55
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• 1985

The recent problems of adolescents are leading us to amphasize school mental health program. Therefore, for the first step of that program, this study was attempted to find out the students' daily life stress, their adaptation beharior to resolve that stress, and their self-concept which has an effect on that beharior, to analyze the relationship among those three variables, and to provide basic data which help maintain and promote students' adaptability and mental health. The subjects were 4 classes each grade, 743 students who were chosen as a sample subject among the total of 3,250 students of a junior girls' school in Seoul by stratified sampling method. The Oquestionnair surrey was done from April 1, 1985 to April 6, 1985. The instruments were (1) a part of Junghoon chois' perceptual Orientation Scale for measuring self-perception of students, (2) Rosenberg's Questionnair for measuring students' evaluation of self-esteem, (3) modified Bell's Adoptive Behavior Questionnair, and (4) the Measuring scale for stress developed by the investigator. The collected data were analyzed by using descriptive statistics, x²-test, t-test, ANOVA, and Pearsons' Correlation. The results are summarized as follows: 1. The range of mean score of self-concept, stress, and adaptation beharior is 1-5 respectively. The mean score of self concept was 3.45. The mean score of stress was 2.53, and the degree of stress was in order of the problem of study and grade marks, girl friend, appearance, and relaxation. The subjects preferred effective long-term adaptation method (Mean=2.81) to ineffective short-term adaptation method. (Mean=2.47) 2. The self-concept had the highest degree when students were 1st grade, in good health condition, taking high grade marks, both parents existing, fathers' educational level being above college, and being in high economic status. The degree of stress was significantly high when students were 3rd grade, in poor health condition, having low grade marks, being in poor economic status, and fathers' educational level being under elimentary school. In relation with adaptation method, 1st grade students used more sbort-term and long-term method, and when students had high grade marks, being in high economic status. they used more long-term adaptation behavior. 3. Two Hypotheses of this research were tested: Hypothesis 1. "The higher the students' self-concept is, the more they use long-term adaptation method." was accepted. (r=.2482, p<.01) (t=-4.99, p<.001) Hypothesis 2. "The higher the students' stress is, the more they use short-term adaptation method." was accepted. (r=.2897, p<.01) (t= -7.51, p<.001) In conclusion, a person in charge of school health can help students to adapt effectively by planning and implementing methods which highten their self-concept and lower their stress. But because the correlation among self-concept, stress and adaptation behavior was at a low level, I think that the study, which confirm the relationship of those three variables, is needed.

• 간호행정학회지
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• 제14권3호
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• pp.287-296
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• 2008

Purpose: This study is descriptive survey to offer basic data of nursing management practice as identify the relationship between Professional Self-Concept, Organizational Commitment and Job satisfaction, whom nurses work general hospitals less than 250 beds. Methods: The subjects in this study were random sampling 320 nurse who worked in 9 general hospital in G city that had less than 250 beds, data was collected from 10 to 30 in Apr, 2007. The data were analyzed using descriptive statistics, Pearson‘s correlation, t-test, ANOVA, Scheffe test. Results: Level of Professional Self-Concept of nurses was average 2.60 point, level of Organizational Commitment of nurses showed 2.83 point, level of Job Satisfaction of nurses showed 2.73 point. There was a statistically significant difference at Professional Self-Concept of nurses as general characteristics showed a marriage state, position, work place, clinical career. There was a statistically significant difference at Organizational Commitment of nurses as general characteristics showed a marriage state, position, clinical career. There was a statistically significant difference at Job Satisfaction of nurse as general characteristics showed a marriage state, position, clinical career. There were highest correlation Organizational Commitment with Job Satisfaction(r=.536, p<.001), also high correlation Organizational Commitment with Professional Self-Concept(r=.478, p<.001). And there were high correlation Job Satisfaction with Professional Self-Concept(r=.422, p<.001). Conclusions: As integrate of the study result showed the Professional Self-Concept had correlation to Organizational Commitment and Job Satisfaction, specially as relation those valuables with general characteristics of subjects, it strongly need to develop educational program for improving Professional Self-Concept with supporting of variety administration for developing human resource for nurses who are not married, low position in hospital, short career, or worked in inpatient wards.