• 소성∙가공
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• 제28권4호
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• pp.175-182
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• 2019

In this study, compression process is performed on the seamless E235 pipe using the newly developed compression technology for seamless pipe. Experimental analysis on the heterogeneity of microstructures and mechanical properties of the deformed seamless pipe is conducted. As a result, the correlation between microstructures and mechanical properties are determined. The spatial distribution of effective stress and effective strain developed in the seamless pipe deformed through compression is analyzed using the finite element method (FEM) based on different inner pressure conditions. From the results of the FEM, the impact of the inner pressure on effective stress and effective strain of the seamless pipe deformed through compression can be understood theoretically.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2009년도 추계학술대회
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• pp.1-7
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• 2009

Most industrial accidents occur when the workers' unsafe behavior and the unsafe situation of workplace take place at the same time. Although human's unsafe behavior is indispensable to work field, the evaluation scheme to detect the causes for the accident resulted from human's unsafe behavior and counterplan should be prepared to prevent and reduce accident. To do this, we first classify the specific background factors in terms of human inner factor and environment factor and then develop the AHP (Analytic Hierarchy Process) model to analyze the background factors that affect the worker's unsafe behavior. We also develop a checklist to be able to evaluate the occurrence possibility of individual worker's unsafe behavior.

• 한국지능시스템학회논문지
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• 제19권1호
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• pp.108-114
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• 2009

본 논문에서는 3차원 작업 환경에서 휴머노이드 로봇의 행동 프리미티브를 이용한 행동 계획 방법을 제안하였다. 또한 휴머노이드 로봇이 효과적으로 다양한 작업을 수행하기 위하여 행동 프리미티브를 정의하였다. 행동 프리미티브를 이용함으로써 다양한 장애물을 갖는 복잡한 작업 환경에서 로봇에 장착한 센서로 외부 환경 정보를 받아들이고 이를 이용하여 실시간 대응 및 작업이 가능하도록 하였다. 제안한 행동 계획방법은 임베디드 비전 시스템을 사용한 휴머노이드 로봇을 실제 제작하여 실험을 통해 성능을 검증하였다.

• Structural Engineering and Mechanics
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• 제64권2호
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• pp.195-204
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• 2017

Analytical and experimental studies of the innovative pipe in pipe damper have been recently investigated by the authors. In this paper, by adding lead or zinc infill or slit diaphragm inside the inner pipe, it is tried to increase the equivalent viscous damping ratio improving the cyclic performance of the recently proposed multi-level control system. The damper consists of three main parts including the outer pipe, inner pipe and added complementary damping part. At first plastic deformations of the external pipe, then the internal pipe and particularly the added core and friction between them make the excellent multi-level damper act as an improved energy dissipation system. Several kinds of added lead or zinc infill and also different shapes of slit diaphragms are modeled inside the inner pipe and their effectiveness on hysteresis curves are investigated with nonlinear static analyses using finite element method by ABAQUS software. Results show that adding lead infill has no major effect on the damper stiffness while zinc infill and slit diaphragm increase damper stiffness sharply up to more than 10 times depending on the plate thickness and pipe diameter. Besides, metal infill increases the viscous damping ratio of dual damper ranging 6-9%. In addition, obtained hysteresis curves show that the multi-level control system as expected can reliably dissipate energy in different imposed energy levels.

• 한국정보통신학회논문지
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• 제15권1호
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• pp.169-174
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• 2011

짧은 바깥쪽 탄소 나노튜브를 가진 이중벽 탄소 나노튜브 공진기의 경우, 자유로운 끝은 긴 안쪽 벽의 진동에 중요한 역할을 한다. 짧은 안쪽 탄소 나노튜브를 가진 이중벽 카본 나노튜브 공진기의 경우, 안쪽은 부드러운 코어로 작동하여 기본 주파수가 이들의 길이에 의해 영향을 받는다. 본 논문에서는 서로 다른 길이를 가지고 나노튜브로 구성된 이중벽 탄소 나노튜브 공진기의 주파수 변화를 분석한다. 분석 결과, 안쪽 혹은 바깥쪽 탄소 나노튜브 길이를 제어하는 다양한 주파수 소자를 구현하는데 널리 응용될 수 있을 것으로 판단된다.

• 한국분무공학회지
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• 제19권2호
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• pp.75-81
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• 2014

Swirl flow in the gun type burner has a decisive effect on the stabilization of the flame, improvement of the combustion efficiency, and also a reduction of NOx. This swirl flow is created by the spinner which is inside the airtube that guide the combustion air. Gun type burner has generally the inner devices composed nozzle adapter, spark gap ignitor, and spinner. These inner components change the air flow behavior passing through air tube. Meanwhile, turbulent characteristics of this air flow are important to understand the combustion phenomena in the gun type burner, because the mixture of fuel and air are depended on. However, nearly all of the studies have been analyzed the turbulent flow of simplified combustion formation without the inner devices. So, this study conducted the measurement using by hot-wire anemometer and analyzed turbulent flow characteristics of the swirl flow discharged from the air tube with inner devices. Turbulence characteristics come up in this study were turbulence intensity, kinetic energy and shear stress of the air flow with the change of the distance of axial direction from the exit of the air tube.

• 한국의류학회지
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• 제22권2호
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• pp.267-278
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• 1998

The purpose of this study was to investigate the degree of self-monitoring (SM), the task situation and the appeal type of advertising impact on consumer behavior: in inner wear purchase. Information for the study was obtained with the use of experimental design. the experimental materials for the study were two-type inner wear advertisements (image appeal Ad/product appeal Ad). The subjects were 270, who were randomly sampled women undergraduate students in Korea, and main-test subjects (70 high SM subjects/69 low SM subjects) were assigned to the cells of 2 (self usage/gift-giving)x2 (quality appeal Ad/image appeal Ad). According to the 2x(2$\times$2) mixed factorial design, the level of SM score, the type of task situation score and the level of appeal type of advertising score were compared and tested by analysis of ANOVA. The results of experiment were as follows: 1. Experimental 1. the results showed the product preference on inner wear was the significant 3-way interaction effects among the degree of SM, the task situation, and the appeal type of advertising as well as the significant main effects of the appeal type of advertising. That is, the situation impact differs from the appeal type of advertising according to the degree of SM. 2. Experimental ll. the results showed the purchase intention on inner wear was the significant 2-way interaction effects between the appeal type of advertising and the task situation as well as the significant main effects of the appeal type of advertising and the task situation. That is, there is considerable difference in gift-giving situation rather than in self- usage situation according to the appeal type of advertising.

• 대한가정학회지
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• 제25권2호
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• pp.89-107
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• 1987

This study aimed at providing basis data to understand homemanagement by patterning of the life styles of housewives and by analysing the disposition of homemanagement behavior and characterstics of the behavior pattern to the difference of the life style patterns of housewives. The result can be summarized as follows: 1. By utilizing factor analysis and cluster analysis, the life style types of housewives were classified into 4 types, namely, self-fulness type (28.4%), negative stagnation type (22.7%), fashion-convenience type (23.3%), innovation-urging type (25.6%). 2. The life style types of housewives which were classified, differed significantly according to all of the demographic variables except family size variable. 3. The disposition of homemanagement behavior which were classified into inner-directed type and other-directed type, differed significantly according to the husband's age variable. 4. The patterns of homemanagement behavior which were classified into market pattern and service pattern, differed significantly according to the all of the demographic variables. 5. The disposition and the pattern of homemanagement behavior differed significantly according to the life style types of housewives.

• 콘크리트학회논문집
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• 제17권6호
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• pp.1025-1032
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• 2005

이 연구에서 격막이 설치된 각형 CFT 기둥의 장기거동에 관한 실험과 해석을 수행하였으며, 이를 통해 각형 CFT 기둥의 장기거동에 미치는 격막의 영향을 파악해 보고자 하였다. 격막의 크기에 따라 두 가지, 기둥 길이에 따라 세 가지 변수를 두어 총 6가지의 변수에 대한 실험과 각 실험체에 대한 3차원 유한요소 해석을 수행하였다. 강관과 콘크리트의 계면 거동을 고려한 유한요소 해석은 격막이 설치된 CFT 기둥의 실제 거동을 정확히 모사하였으며, 이를 통해 유한요소 모델링의 정확성이 검증되었다. 실험과 해석 결과로부터 다음과 같은 결론을 얻었다. 격막에 의한 기둥 단부의 구속 효과는 기둥의 길이에 상관없이 CFT 기둥의 단부에서 기둥의 폭만큼 내려간 위치까지이며, 이외의 부분에서 격막 또는 강관에 의한 구속 효과는 나타나지 않았다. 또한 내부 콘크리트 면적의 1/2 이상을 가압할 수 있는 격막이 설치된 각형 CFT 기둥의 장기변형에 의한 축소량은 강관과 콘크리트의 전체 면적을 동시에 가압한 경우의 축소량과 동일하다.

• 디지털융복합연구
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• 제15권11호
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• pp.611-620
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• 2017

이 연구의 목적은 휘트니스센터 지도자의 감정노동과 직무소진 및 직무만족의 관계를 규명하는 것이다. 이를 위해 인천지역 소재 휘트니스센터에서 근무하고 있는 지도자를 모집단으로 설정, 편의표본추출법을 이용하여 총 323명의 자료를 실제 분석에 사용하였다. 분석방법은 빈도분석, 확인적 요인분석, 신뢰도 검증, 구조방정식모형 분석을 실시하였다. 이를 통해 얻어진 결론은 다음과 같다. 이 연구는 휘트니스센터 지도자의 감정노동과 직무소진 및 직무만족의 관계를 실증적으로 구명하는데 목적이 있다. 이에 본 연구결과와 논의를 통해 다음과 같은 결론을 도출하였다. 첫째, 휘트니스센터 지도자의 감정노동 중 내면행위는 직무소진에 부정적인 영향을 미치는 것으로 나타났다. 둘째, 휘트니스센터 지도자의 감정노동 중 표면행위는 직무소진에 긍정적인 영향을 미치는 것으로 나타났다. 셋째, 휘트니스센터 지도자의 직무소진은 직무만족에 부정적인 영향을 미치는 것으로 나타났다. 넷째, 휘트니스센터 지도자의 감정노동 중 내면행위는 직무만족에 긍정적인 영향을 미치는 것으로 나타났다. 다섯째, 휘트니스센터 지도자의 감정노동 중 표면행위는 직무만족에 부정적인 영향을 미치지 않는 것으로 나타났다.