• Wind and Structures
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• 제8권2호
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• pp.135-146
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• 2005

Divergent galloping-like motion of a dry inclined cable has been observed in a limited number of experimental studies, which, due to the uncertainties in its onset conditions, has induced serious concerns in the bridge stay cable design. A series of dynamic and static model wind tunnel tests have been carried out to confirm the existence of the phenomenon and clarify its excitation mechanism. The present paper focuses on exploring the spatial flow structure around an inclined cable. The pattern of resultant aerodynamic forces acting at different longitudinal locations of the model and the spatial correlation of the forces are examined. The results lead one step closer in revealing the physical nature of the phenomenon.

• 한국수소및신에너지학회논문집
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• 제11권3호
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• pp.127-136
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• 2000

Molecular dynamics simulations have been carried out to investigate the scattering and penetration properties of hydrogen ions with the normal incident angle to Ni (100) surface. The initial kinetic energies of hydrogen ions range from 100 to 1,600 eV. The simulation results are used to assess the applicabilities of theoretical predictions based on the binary collision approximation, and, in the high kinetic regime, theoretical results for scattering energies were shown to he a good agreement with molecular simulations. The angle dependencies on both scattering and penetration distributions were found in the longitudinal direction, but not in the azimuthal direction except for the high kinetic energy of 1,600 eV.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.250-253
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• 2006

This paper presents experimental studies on investigating the seismic retrofit performance of reinforced concrete circular columns with poor lap-splice details using GFRP wrapping. Four 1/2 scale-down model columns have been tested. The as-built column is expected to suffer brittle failure due to the bond failure of lap-spliced longitudinal reinforcement. The retrofitted columns using GFRP wrapping showed significant improvement of seismic performance.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1923-1929
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• 2003

The present study investigated the microcirculation of blood in the left common artery (LCCA). In order to develop a mathematical model for microcirculation in LCCA, the present study adopted preexisted set of measured morphological data on anatomy, mechanical properties of the coronary vessels, viscosity of blood, the basic laws of physics, and the appropriate boundary conditions. In this study, the statistical distribution of blood pressure, blood flow, and blood volume in the LCCA were determined based on the anatomical branching pattern of the coronary arterial tree and the statistical data of blood vessel dimensions. Our calculations were in good agreement with the previous studies. The present results showed that the mean longitudinal pressure drop profile was function of the vessel order numbers. It was found that the normalized pressure drop was a logarithmic function of the compliance.

• Asia pacific journal of information systems
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• 제12권1호
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• pp.17-44
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• 2002

This study is to propose a framework for analyzing the role of information systems in organizations, and to make an overture it's applicability for empirical studies to be performed in the future. To accomplish these purposes, this study identified major dimensions which can explain the introduction of various applications based on the interviews with IS staffs of a domestic car manufacturing firm, and reviewed the past researches which discussed the roles of information systems regarding those dimensions. From this mixed approach, this study defined the research dimensions to analyze the role of information systems, which are consisted of the purpose of information processing and the scope of information processing. And then, this study performed the longitudinal case study to analyze the role of information systems in organizational growth based on the framework.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.875-880
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• 2001

This paper deals with the free vibrations curved beams with elastic springs. Taking into account the effects of rotatory inertia and shear deformation, differential equations governing the free vibrations of such beams are derived, in which each elastic spring is modeled as a discrete Winkler foundation with very short longitudinal length. Differential equations are solved numerically to calculate natural frequencies and mode shapes. In numerical examples, the circular, parabolic, sinusoidal and elliptic curved members are considered. The parametric studies are conducted and the lowest four frequency parameters are reported in tables and figures as the non-dimensional fonns. Also the typical mode shapes are presented.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.706-711
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• 2005

From the using CWR (Continuously Welded Rail) on steel plate girder bridges without ballast, axial forces are occurred from a temperature on CWR and girders. Because of the additional axial forces, studies in order to CWR and developments of devices are proceeding. The track system of steel plate girder bridges is poor. When CWR is used for the system, the resistance on sleepers is increased from a temperature. So it is increasing an effect on CWR and, for solving the effect, longitudinal forces for buckle are being decreased. It is possible that opposite cases can be happened and it is also compared and studied. Therefore, we present a reasonable model for analyzing CWR within the property of steel plate girder railway bridges in Korea. Furthermore, the results analyzed for stability is compared and evaluated with tests. Finally, a reasonable method for the installation of CWR on bridges without ballast is suggested.

• 응용통계연구
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• 제17권2호
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• pp.185-196
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• 2004

농작물에 기주하는 해충의 밀도추정은 해충종합적 관리(Integrated Pest Management: IPM)의 중요한 연구분야이다. 이는 농약을 살포한다든지 천적을 방사하는 것과 같은 인위적인 방제관리의 성패여부가 해충밀도에 대한 정보에 의존하기 때문이다. 본 연구는 온실장미에서 서식하는 점박이응애의 밀도분포를 일반화 선형혼합모형을 통하여 분석하고 있다. 자료습득이 식물체의 일정 부위에서 반복적으로 이루어 졌기 때문에 경시적 자료분석의 개체특정(Subject-Specific: SS)방법과 모집단평균(Population-Averaged: PA)방법을 모두 사용한 후에,그 결과를 비교, 검토 하였다.

• 가정과삶의질연구
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• 제25권1호
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• pp.59-75
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• 2007

This review synthesizes research during the past 15 years on the family relations of older persons. After discussing two background issues-sociodemographic changes of later life families and the status of the elderly-the following topics are addressed; relationships between aged parents and adult children, couple relationships, grandparents' relationship with their grandchildren and sibling relationships. Family relationships are vital support systems providing emotional and instrumental support in the lives of older persons. Mutual assistance and affection among family members were found to be common characteristics. Although research on family gerontology has increased in quantify, there are feater needs to develop qualitative, longitudinal and theory grounded studies to capture the rich complexity of family life. Other challenges and suggestions for future research on older persons' family relationship are presented.

• 의학교육논단
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• 제16권2호
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• pp.57-66
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• 2014

Burnout research has mostly been performed in human service fields. However, it has recently been expanded to cover diverse settings and even non-occupational samples, such as students. In this study, we defined the construct of academic burnout, which is the burnout experienced by students. Next, we described the concept of academic burnout by introducing measurements for assessing academic burnout. On the basis of the demand-control model (DCM) and effort-reward imbalance model (ERIM), which are the most predominant theoretical burnout models, we described the causal factors and the pathway to experiencing academic burnout symptoms. The ERIM was a more influential model than the DCM when explaining the academic burnout of Korean students. Based on the results of previous longitudinal studies on academic burnout, we recognized emotional exhaustion and academic inefficacy as the initial symptoms of academic burnout. Finally, we discussed the prevention and intervention programs with specific components that should be included in those programs.