• 대한기계학회논문집B
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• 제24권6호
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• pp.852-859
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• 2000

The emission in the exhaust gas from diesel engine is effected by the fuel spray characteristics. The spray of D.I. diesel engine impinges on a piston cavity and a cylinder wall. It is very important to know exactly the distribution and behavior of the spray inside cylinder. The objective of this study is to develop more accurate evaporation model. The EPISO code was used to analyze the flow characteristics in the engine. The Wakil model and the Faeth model are applied to the EPISO code to analyze the behavior of impinging spray. And also experimental and numerical analysis were carried out. The spray behavior characteristics were investigated by changing injection pressure, ambient pressure and temperature. The behavior of impinging spray was strongly effected by the change of ambient pressure and temperature. The effects of evaporation and rebounding droplet should be considered.

• 한국가시화정보학회지
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• 제17권1호
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• pp.10-18
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• 2019

In this study, the temperature behavior of Pulsating Heat Pipe (PHP) according to the diameter change were studied by limiting the diameter change to only the evaporator. To investigate operation of PHP in various heat input, heat input power was increased from 10 to 120 W. The results show operation can be divided into 3 regimes by temperature behavior. Thermal resistance was increased before start-up and decreased with increasing heat input. At 110 W heat input, thermal conductivity of 2 mm PHP was 8 .times higher compare to thermal conductivity of copper. Further, to investigate details of temperature behavior in higher heat input, FFT analysis was conducted. Based on the results, when the deviation of peak frequency in each section is lowest, the thermal resistance has lowest value.

• 대한지역사회영양학회지
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• 제13권1호
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• pp.34-45
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• 2008

For the correct dietary habit and balanced dietary intake of aged people, the nutrition management that fits to the dietary behavior change stage has to be accomplished. In order to do so, in this paper, we chose 175 women that are aged more than 65 years old who are rural long life community residents and surveyed the dietary intake for 2 days including a twice depth interview and the 24 hour recall method. Also, for the sake of our aim, using the transtheoretical model, the dietary behavior change stage group was divided into the contemplation stage group, the preparation stage group, the action stage group and the maintenance stage group. The results are as follows: In the intake amount of protein (p < 0.01), vitamin $B_1$ (p < 0.05) and vitamin $B_6$ (p < 0.05), the intake amount of these nutrients in the action stage group and the maintenance stage group were significantly larger than the intake amount in the contemplation stage group and the preparation stage group. The nutrition evaluation according to the dietary behavior change stage, the ratio of subjects who took insufficient amount of energy, protein, vitamin A, and vitamin C were low as the dietary behavior change stage was upgraded. The subjects of maintenance stage group were most likely to consume vegetables more than once a day, and consume fruits and milk and milk products more than 5 times/week. MAR [13], MAR [10] and MAR [4] of subjects in the action stage group and the maintenance stage group were significantly higher than MAR [13], MAR [10] and MAR [4] of subjects in the contemplation stage group and the preparation stage group (p < 0.001). From the above results, there were differences of nutrient intakes according to the dietary behavior change stage. Therefore, it is considered that the intervention for the dietary behavior motivation induction has to be advanced before accomplishing the individually fitting intervention at the time of nutrient management intervention.

• 대한교통학회지
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• 제35권4호
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• pp.332-347
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• 2017

자율주행기술이 교통류에 미치는 영향을 분석하기 위해서는 자율차와 비자율차 간의 상호작용을 분석하는 것이 중요한 이슈이다. 특히 자율주행기술을 활용한 유용한 서비스 중의 하나인 군집주행은 주변의 비자율 차량의 주행행태에 영향을 미칠 수 있다. 본 연구의 목적은 군집주행 환경에서 비자율차의 차로변경행태 분석하는 것이며, 3단계의 실험 및 조사를 수행하였다. 1단계 영상기반 인지특성 분석을 통해 군집주행 환경에서 어떠한 반응행태를 보일 것인지를 조사하였으며, 2단계 주행시뮬레이션 실험을 통해 비자율차의 차로변경행태를 분석하였다. 차로변경행태를 분석하기 위해 차로변경시간과 교통류의 안전성을 나타낼 수 있는 지표인 가속소음을 이용하였으며, 자율차의 시스템 보급률(Market Penetration Rate, MPR)과 피실험자 인적요소에 따른 비자율차의 주행행태 차이를 비교 분석하였다. 마지막 단계인 NASA-TLX(NASA Task Load Index)를 통해 비자율차 운전자의 작업부하를 평가하였다. 분석결과 군집차량군 주변의 비자율차 운전자는 심리적인 부담감을 느끼며, MPR이 증가할수록 차로변경시간이 길어지고 30-40대 운전자 또는 여성 운전자의 경우 안전성이 낮아지는 것으로 나타났다. 본 연구에서 도출된 결과는 자율차와 비자율차의 상호작용을 반영한 보다 현실성 높은 교통시뮬레이션 실험 시 기초자료로 활용될 수 있고, 이를 기반으로 자율협력주행 환경에서 적용 가능한 교통운영관리전략 수립을 효과적으로 지원할 것으로 기대된다.

• 보건행정학회지
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• 제11권3호
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• pp.121-150
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• 2001

This study was conducted to investigate provider's behavior change after releasing the information on the Cesarean section rate. Claims data filed at the National Health Insurance Corporation was used for this analysis and the focus of this study was the change of cesarean rate after the public disclosure of information. Average rates of the year 1999 and 2000 were compared, on the institutional basis, and range and coefficient of variation were estimated. For the last decade, Cesarean section rate has been increased dramatically. Clinical or demographic factors could not adequately explain the increase. Instead, nonclinical factors, such as financial incentive, physician's convenience, practice characteristics, etc., were more significant in explaining the increasing rate. Providers' behavior was significantly affected by the public release of information: after the release, average rate was decreased by 10.2%, and variations were also decreased. In particular, the extent of decrease was explained mainly by nonclinical factor rather than clinical ones. The results suggest that disseminating practice information to providers and consumers could contribute to reducing unnecessary medical service.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.408-415
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• 1996

This study is aimed to define the behavior of the girder ledge of precast girder-beam joint in rame type precast concrete construction method. The variable of this study is followed : 1) The change of the maximum shear strength depended on the transformation of concrete compressive strength 2) The change of the behavior of ledge depended on the transformation of shear-span ratio 3) The change of maximum shear strength and ductility by the type of reinforcement. The results of this study show the behavior of ledge is affected by shear-span ratio and the maximum shear strength is depended on the concrete compressive strength, reinforcement ratio and effective section area. In addition, through the investigation of the established study, the results of this study suggest the shear friction formula of Raths.

• 교육시설 논문지
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• 제21권3호
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• pp.11-18
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• 2014

This study was carried out to observe movement behavior of students about a change of physical condition in moving space of variation type using simulation technique. The moving pattern of students was checked by SIMULEX program. The width of corridor was adjusted to 2.4m, 3.0m and 3.9m and a flow coefficient of simulation was estimated with the change of width. The wider the width of corridor was, the lower a flow coefficient was, and the difference was large when the width of corridor was narrow. It was also observed that the flow coefficient was relatively high in all types of corridor setup individual locker. Unit occupation area with the change of width was additionally measured, as shown in the results, the occupation density was low when the width of corridor was wide and a stationary time was short.

• Asia pacific journal of information systems
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• 제23권2호
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• pp.87-109
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• 2013

While many surveys show very positive attitudes on the part of consumers towards eco-friendly products, the market share actually reflecting green IT purchases remains low in most countries. The motivations behind green IT purchase behavior are still obscure. Several studies have addressed the question of green IT diffusion from economic and normative viewpoints in an attempt to interpret IT adoption behavior. This study comes at the question from a different angle, namely negative frame, examining threat and coping behaviors using the Ordered Protection Motivation (OPM) model and threat appraisal theory. The results show that attitudes toward fairness and positive change, which are precedents of threat appraisal, play an important role in determining threat appraisal. Perceived threats in the green IT arena include habit change and ecological change. Appraisal for coping with these threats directly affects initial adoption behaviors regarding available green IT, and then indirectly encourages the purchase of new green IT products.

• 지역사회간호학회지
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• 제22권2호
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• pp.173-183
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• 2011

Purpose: This study was to compare the Transtheoretical Model components according to the stage of change in smoking cessation behavior and identify factors associated with preparation to quit smoking among college smokers. Methods: Data were collected from 224 undergraduate students using the self-report questionnaire. The survey variables comprised the stage of change in smoking cessation, self-efficacy, and decisional balance and process of change in smoking cessation. Results: There were significant differences in self-efficacy, cons of smoking, and the process of change according to the stage of change in smoking cessation behavior. Cons of smoking and self liberation were significant factors related to the preparation stage of smoking cessation. Conclusion: Strategies to enhance cons of smoking and self liberation in college smokers will be an important intervention component to prepare and plan smoking cessation in future studies.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 춘계정기학술대회
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• pp.253-260
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• 2001

Understanding and adapting to changes of customer behavior is an important aspect for a company to survive in continuously changing environment. The aim of this paper is to develop a methodology which detects changes of customer behavior automatically from customer profiles and sales data at different time snapshots. For this purpose, we first define three types of changes as emerging pattern, unexpected change and the added / perished rule. Then we develop similarity and difference measures for rule matching to detect all types of change. Finally, the degree of change is evaluated to detect significantly changed rules. Our proposed methodology can evaluate degree of changes as well as detect all kinds of change automatically from different time snapshot data. A case study for evaluation and practical business implications for this methodology are also provided.