• Journal of Mechanical Science and Technology
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• 제19권7호
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• pp.1503-1516
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• 2005

Mean flow and turbulence properties of developing turbulent flows in a 90 degree square bend with span-wise rotation are measured by a hot-wire anemometer. A slanted wire is rotated into 6 orientations and the voltage outputs from them are combined to obtain the mean velocity and the Reynolds stress components. Combined effects of the centrifugal and Coriolis forces due to the curvature and the rotation of the bend on the mean motion and turbulence structures are investigated experimentally. Results show that the two body forces can either enhance or counteract each other depending on the flow direction in the bend.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.170-177
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• 2004

A single degree of freedom system and transmissibility are key concepts in many problems of vibration isolation. In order to apply this approach, however, several assumptions must be satisfied, which are often not realistic. In this paper, an approach using vibration power flow is introduced to deal with vibration isolations in a more practical way. Procedures of this approach and some results of research are presented. Difficulties in this method are also discussed.

• 한국물환경학회지
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• 제28권6호
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• pp.933-942
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• 2012

The purpose of this study is to evaluate the degree of waterbody impairment according to the flow conditions and present to the appropriate water quality improvement alternatives using observed water quality and flow for Total Maximum Daily Load (TMDL) implementation at 39 unit watersheds the nakdong river basin. Observed water quality data for 7 years are divided into five cumulative flow frequency group and comparing the each observed water quality data and TMDL Target water quality (TWQ) the last evaluate the water quality is impaired group. We found that the cumulative flow frequency group-specific the average excess rate of V group was the highest (32.86%), followed by the IV group (26.04%), group III (23.36%), II group (22.67%), I group (20.70%), the degree of impaired waterbody tended to be inversely proportional to the flow rate. Resulted from cumulative flow frequency group of impaired water quality assessment, 13 unit watersheds are impaired from a group IV and group V affected by point sources. Therefore, improvement of sewage discharge and the initial composition of the riparian buffer zone are needed. Nakbon F, Namkang D and Namkang E within 13 unit watersheds are impaired from group II and III affected by non-point sources. Therefore, application of Best Management Practices (BMPs) is needed for these watersheds. Evaluation of impaired waterbody using Cumulative flow frequency group is able to determine the extent of the judgment to TWQ exceeded by the flow conditions and helps proper setting Standard flow and planning pollutant reduction for TMDL.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.29-34
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• 1996

In the present paper, the flow distribution in the hot air drying chamber of a sizing machine was numerically analyzed with respect to the geometries of the intake duct to obtain the more uniform flow distribution in the chamber. The result shows that the velocity distribution in the inlet of the chamber was significantly dependent on the the geometry of the intake duct. The degree of the non-uniformity in the chamber was reduced as the incident angle of the intake duct became to be smaller.

• 마케팅과학연구
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• 제12권
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• pp.59-75
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• 2003

본 연구는 Hoffman and Novak(1996)을 중심으로 마케팅 분야에서 연구되기 시작하는 flow 개념을 인터넷 환경에서 소비자들의 구매의도 관련변수를 중심으로 하여 지각된 위험, 관여도와 서비스품질에 어떠한 영향을 미치며 더 나아가 구매의도에 미치는 영향력을 파악하고자 연구를 진행하였다. 본 연구의 구체적인 목적은 첫째, 선행연구를 기초로 전자상거래에서 flow 개념을 이해하기 위해 기존의 flow 관련 연구를 살펴보고, 숙련도와 도전감으로 분류한다. 둘째, flow개념이 지각위험, 관여도 더 나아가 구매의도와의 상호관계를 정립하여 이를 모형화하고 검증한다. 즉, flow의 구성 요인인 숙련도, 도전감에 있어서 지각된 품질, 지각된 위험과 관여도와의 영향관계를 파악하고 구매의도와의 영향관계를 알아보고자한다. 따라서 본 연구에서는 인터넷 환경에서 소비자의 구매행동을 파악하고 특히 어떤 요인들이 소비자들의 구매의도를 결정짓는지를 알아보기 위하여 최근에 연구되고 있는 flow개념이라는 이론적 틀에 바탕을 두어 소비자 구매의도 결정요인들을 분석하고자 한다. 연구 결과, 숙련도와 도전감이 높울수록 관여도와 지각된 품질은 증가하고 숙련도는 도전감보다 지각된 위험에 부의 영향을 미치며, 지각된 품질은 관여도와 구매의도에, 지각된 위험은 구매의도에, 관여도는 구매의도에 유의한 영향을 미치는 것으로 나타났다.

• 대한통합의학회지
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• 제4권1호
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• pp.65-72
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• 2016

Purpose : This study was carried out to find out the relationship between emotion intelligence, learning flow and career stress of nursing students and influence factors for career stress. Methods : This study targeted 197 university students in their freshman-senior year attending College of Nursing located in P Metropolitan City. For collected data, real numbers and percentage, mean and standard deviation and multiple regression analysis were carried out by using PASW 21.0 program and the correlation between emotion intelligence, learning flow and career stress was analyzed with Pearson's correlation coefficients. Results : Emotional self-awareness(M=3.80, SD =.71), clear goals(M=3.39, SD=.90) and school environment stress(M=2.97, SD=.96) were found to be high in the degree of emotion intelligence, learning flow and career stress of the subjects. The relationship between emotion intelligence and learning flow showed a positive correlation(r=.489, p<.01) in the correlation between emotion intelligence, learning flow, career stress and emotion intelligence showed a negative correlation with career stress(r=-.204, p<.01). Emotion intelligence and learning flow show that career stress is predicted significantly (${\beta}$ =-.15, p < .01) and explained a career stress variate as 18%(F = 24.5, p < .01). Conclusion : Emotion intelligence of nursing students was found to be very influential on the degree of learning flow or career stress. Based on the results of this study, replication studies on emotion intelligence and career stress are needed and the development of intervention programs to increase emotion intelligence is needed.

• 멤브레인
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• 제4권3호
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• pp.142-151
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• 1994

역삼투 공정을 농축공정에 이용하기 위해 향류식 역삼투 나권형 모듈을 고안, 제작하여 염수의 농축실험을 수행하였다. 역삼투 분리의 배제도와 농축도의 관계를 고찰한 결과, 배제유량에 대한 투과유량의 비가 양쪽 관계의 중요한 매개 변수이며, 반사계수 값에 따라, 역삼투막의 배제도와 농축도가 Spiegler-Kedem 식의 경향을 따른다. 향류식 역삼투 공정은 일반 역삼투 농축 공정에 비해 농축의 장애 요소인 삼투압차를 효과적으로 저하시키는 효과가 있으며 농축도가 상대적으로 우수하였다. 향류식 나권형 모듈의 수치모사 결과 농축공정의 농축도 증가를 위해서는 모듈의 지름보다 모듈의 길이를 늘리는 것이 유리함을 알 수 있었다.

• 산업기술연구
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• 제26권B호
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• pp.83-92
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• 2006

A probabilistic analysis model. one of reliability analysis methods introducing the concept of variables, was developed to investigate the uncertainty of dominant factors influencing the degree of consolidation in the radial consolidation theories. Based on the developed probabilistic analysis model, sensitivity study of those factors was performed to find their trends of affecting the degree of consolidation in the vertical drain method. Various radial consolidation theories, proposed by Barron(1948), Hansbo(1979), Yoshikuni(1979) and Onoue(1988), were used for this parametric study with the influencing factors such as size of smear zone, reduction ratio of permeability in the smear zone, discharge capacity, permeability for horizontal flow and coefficient of consolidation for horizontal flow. As results of this sensitivity study, for the given consolidation theory, contribution of each factor to the degree of consolidation was figure out and compared to each other. For the given value of each factor, the sensitivity to the degree of consolidation in the various theories was evaluated and their applicability and limitations were assessed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2632-2637
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• 2007

Rotary performance and flow resistance induced by each element in suction nozzle of a vacuum cleaner with a double-blade rotary fan are investigated numerically and its relation with flow-induced noise and rotary performance is examined. Flow resistance and vorticity in suction nozzle are calculated and it is found that they are closely related with flow-induced noise. Gap between double blades, adoption of cross-flow fan, enlargement of flow inlet area, and optimization of blade number are tested for noise reduction. Finally, the effects of each method are verified experimentally. It is found that several combinations of the proposed methods can be adopted for noise reduction although the degree of reduction is not much.

• 한국지반환경공학회 논문집
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• 제13권6호
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• pp.59-66
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• 2012

본 연구의 목적은 다양한 경사를 가진 비탈면에서 토석류의 거동과 메카니즘을 평가하는 것이다. 수치모의는 질량보존 및 운동량 보존에 관한 방정식에 기초하여 유한차분법을 이용하여 수행되었다. 토석류 유동 메카니즘은 토석류, 소류집합유동, 소류이동 등의 3가지 형태로 나눌 수 있다. 우선 하류부에서 공급유량의 변화에 따른 직선 사면과 2단 경사 사면에 대한 유량, 유동심, 토사체적 농도를 조사하였다. 공급유량이 적을수록 토석류가 도달한 직후에만 유량과 유동심의 상승이 있었고, 이후 감소하는 경향을 나타내지만, 공급유량의 증가로 인해 유량과 유동심의 곡선이 불안정하면서 높게 나타났다. RMS비 비교 결과 2단 경사 비탈면이 직선 비탈면보다 유량과 유동심이 적게 나타난 것을 확인하였다. 둘째, 2단 경사 비탈면에서 하류부의 경사각도 변화에 따른 유량, 유동심, 토사체적 농도를 조사하였다. 하류부 경사각도 $14^{\circ}$와 $16^{\circ}$사이의 유량과 유동심 곡선의 밴드폭이 다른 각도 사이보다 크게 나타났으며, 10초 이후에는 높은 값의 파동이 지속된다는 것을 확인하였다.