• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.812-817
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• 2004

Recently drastic improvement of railway technology has been accompanied by the construction of very high-speed tracks. It should be noticed that Continuously Welded Rail(CWR) has played significant role in technical development of railway and that installation of CWR is now being scheduled on existing lines as well as newly-built lines. In general, interaction between CWR and bridge deck takes place on bridge section and additional axial force and displacement is to be developed owing to temperature and braking/acceleration forces. This interaction is known to be mainly governed by span organizations and arrangements of foot bearings. In common practice, movable bearing is stationed and designed on the assumption that it is not able to transfer the horizontal force of upper decks. However, it is well known that horizontal resistance is developed in movable bearings due to friction and that friction coefficient of movable bearing is ranged from 0.03 to 0.20 depending on the material of bearings and magnitude of reactions. Therefore, it is easily reasoned out that friction of movable bearing can influence the mutual behavior of CWR and bridge decks. Suggested in this study is to investigate the validity and efficiency of friction effect of movable bearings in controlling the axial force and displacement of CWR on continuous railway bridges.

• KIEAE Journal
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• 제12권6호
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• pp.3-10
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• 2012

Small park in the community is a public asset that is commonly used by the residents daily and performs an important role to activate the community. The purpose of this study is to draw a small park plan through community participation. In concrete, this study tries to find out the demand of the residents about their small park plan, observe the changes in their demand in the process of debate and analyze the effect of the residents' participation. Small group workshop method was adopted in the study and three groups were set up and surveys were made in two stages. Two dimensional pictogram cards and three dimensional digital park formation tools were used. The results of workshop study indicated as follows: Firstly, residents wanted to have community farming garden, green house and flower garden to grow plants, natural walls and safe resting facilities. Secondly, individual and diverse opinions presented at first could be converted to common opinions through mutual exchanges of opinions in the process of debates. Thirdly, digital park formation program functioned well as an effective visual tool to draw the attention and quick responses of the residents and to reach an agreement. It is expected that the results of this study show the effectiveness of residents' participation tools in the process of drawing agreements in the community society that requires the residents' demands and agreement and this study will be usefully utilized in planning community spaces with residents' participation hereafter.

• Computers and Concrete
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• 제24권6호
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• pp.513-525
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• 2019

In this work, an experimental research has been performed on Steel Fiber-Steel Reinforced Concrete (SFSRC)specimens subjected to four-point bending tests to evaluate the feasibility of mutual replacement of steel fibers and conventional reinforcement through studying failure modes, load-deflection curves, stiffness of characteristic points, stiffness degradation curves and damage analysis. The variables considered in this experiment included steel fiber volume percentage with and without conventional reinforcements (stirrups or steel fibers) with shear span depth ratios of S/D=2.5 and 3.5. Experimental results revealed that increasing the volume percentage of steel fiber decreased the creation and propagation of shear and bond cracks, just like shortening the stirrups spacing. Higher crack resistance and suturing ability of steel fiber can improve the stability of its bearing capacity. Both steel fibers and stirrups improved the stiffness and damage resistance of specimens where stirrups played an essential role and therefore, the influence of steel fibers was greatly weakened. Increasing S/D ratio also weakened the effect of steel fibers. An equation was derived to calculate the bending stiffness of SFSRC specimens, which was used to determine mid span deflection; the accuracy of the proposed equation was proved by comparing predicted and experimental results.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1382-1387
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• 2004

From the viewpoint of a macro state, there is no thermal boundary resistance (TBR) at an interface if both surfaces at an interface are perfectly contacted. However, recent molecular dynamics (MD) studies reported that there still exists the TDR at the interface in an ideal epitaxial superlttice. Our previous studies suggested the model to predict the TBR not only quantitatively also qualitatively in superlattices. The suggested model was based on the classical theory of a wave reflection, and provided highly satisfactory results for an engineering purpose. However, it was not the complete model because our previous model was derived by considering only the effects from a mass ratio and a potential ratio of two species. The interaction of two species presented by the Lennard-Jones (L-J) potential is governed by the mutual ratio of the masses, the potential well depths, and the diameters. In this study, we performed the preliminary simulations to investigate the effect resulting from the diameter ratio of two species for the completion of our model and confirmed that it was also a ruling factor to the TBR at an interface in superlattices.

• 대한가정학회지
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• 제41권1호
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• pp.59-76
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• 2003

The relationship between adolescent children and parents has a profound effect on not only the adolescents development into healthy adults but also the psychological welfare of the parent. A program focused to improve adolescents relationship with parents has not been developed until now. To achieve the educational goals enhancing mutual understanding, it is more effective to educate both the parents and adolescent children. Thus, this study developed and carried out a program in which adolescent children and mothers, being fully in charge of raising children, participated. The study analyzed the program effects after implementing on 6 pairs of adolescent children and mothers. The results are as follows: 1) adolescent children and mothers placed high values on the fact that they can understand each other well, 2) both parties accepted each other by recognizing the inevitability of the generation gap, and 3) the program gave them a chance to admit that they should try to communicate openly. Most of all, adolescent children could find self-confidence while mothers could collect valuable data essential to raise children and build a new mother's role model adapting to social changes.

• 한국항공운항학회지
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• 제21권3호
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• pp.65-77
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• 2013

A high brand reputation of a airline means the airline is preferred by passengers because of its unique services being even better than others. This is why airline's specialized services are important in that those services would create a new brand value and build up the airline's brand image, being enable to have competitive advantage over other airlines, to provide satisfied services, to have a mutual trust between passengers and the airline and to create customer's loyalty. A-Airline have been trying to give passengers a joy of flight by providing its customized and specialized cabin services out of airlnes' stereo-typed services.Therefore this paper will find out how their satisfaction of the cabin services have a positive impact on customer loyalty through brand image, brand reputation, brand identity and brand attraction. Those services would not only contribute to upgrade A-airline's corporate image but show the way to which the cabin service is heading also.

• 한국재난정보학회 논문집
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• 제8권2호
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• pp.108-118
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• 2012

현재 TBM공법의 적용은 1985년 이래로 점진적으로 증가되고 있는 추세에 있다. 이 연구는 암반터널에서 탁월한 굴진실적을 갖고 있는 TBM공법의 이해와 운영발전을 위해서 TBM공법을 적용한 시공 사례의 시간손실과 TBM 굴진장의 상관관계를 분석하였다. 그리고 분석 결과를 기 분석된 국내, 미국, 일본의 현장 결과치와 비교 분석하여 TBM 굴진에 영향을 주는 요인을 분석하였고, 그 분석결과에 따른 운영개선방안을 제시하였다. 따라서 이 연구에서 제시한 개선방안은 향후 기본계획수립단계에서 TBM공법 적용 시 개략적인 지표로 활용할 수 있을 것으로 사료된다.

• 농촌계획
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• 제22권2호
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• pp.77-87
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• 2016

Targeting people returning to farming and also people preparing for returning to farming, this study analyzed differences in awareness of conflict factors and conflict management focusing on the conflicts experiencing in the process of their movement and settlement process in rural area. In the results, people preparing for returning to farming showed higher awareness of conflicts and also higher necessity of conflict management than people already returning to farming. Also, both groups preferred individual conflict management to structural conflict management. Based on the results like above, the implications can be summarized like below. First, it would be necessary to have programs informing possible conflicts in advance in the process of returning to farming and also relieving psychological anxiety by providing prior-learning to people preparing for returning to farming. Second, it would be necessary to have individual conflict management measures to establish mutual trust and to form community spirit through regular social gatherings between original residents and people returning to farming. Since the effect of conflict management can be maximized only when the structural and individual conflict managements are properly harmonized, it would be necessary to have the structural conflict management which is relatively felt difficult.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2006년도 춘계학술대회
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• pp.54-65
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• 2006

Since the ending of the IMF period, the Korean health industry has experienced a number of changes in its environment such as hospital bankruptcy, enforcement of SDF(Separation of Dispensing and Prescription), opening of the medical market by WHO, evaluation of medical institutions with more than 100 sick beds, and limited approval for medical service advertisement. Furthermore, the concept of medical service has changed from a beneficent and vortical one to a hi lateral and righteous one. These changes in medical service have required medical institutions to provide customers with medical service options and adopt market principles actively, while considering customer satisfaction. Thus, this paper aims to investigate the service quality and service value of medical institutions, to understand the mutual relationship between customer satisfaction and repeat visits, and to suggest better solutions for the improvement of service quality. For future studies, It will be necessary to overcome the limitations of this research and develop proper measurement tools on service quality in the Korean medical system.

• Korea-Australia Rheology Journal
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• 제17권4호
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• pp.165-170
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• 2005

In this study, high intensity ultrasound was employed to induce mechano-chemical degradation during melt mixing of polycarbonate (PC) and a series of styrene-acrylonitrile (SAN) copolymers. It was confirmed that generation of macroradicals of constituent polymers can lead to in-situ copolymer formation by their mutual combination, which should be an efficient path to compatibilize immiscible polymer blends and stabilize their phase morphology in the absence of other chemical agents. Based on the effectiveness of the compatibilization by ultrasound assisted mixing process, we investigated the effects of viscosity ratio of PC and SAN and AN content in SAN on the compatibilization of PC/SAN blends. It was found that effectiveness of compatibilization is optimal when the AN content is in the range of favorable interaction with PC and the viscosity of the matrix is higher than that of the dispersed phase. In addition, changes in the interfacial tension between PC and SAN were assessed by examining relaxation spectra which were obtained from measuring rheological properties of ultrasonically treated blends.