• Earthquakes and Structures
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• 제9권4호
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• pp.875-891
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• 2015

Earthquake can occur anywhere in the world and it is essential to design important members in special structures based on maximum possible forces that can be produced in them under severe earthquake. In addition, since the earthquake is an accidental phenomena and there are no similar earthquakes, therefore the possibility of strong earthquakes should be taken into account in earthquake-resistant design of important structures. Based on this viewpoint, finding the critical acceleration which maximizes internal forces is an essential factor in structural design. This paper proposes critical excitation method to compute the critical acceleration in design of important members in special structures. These critical accelerations are computed so that the columns' internal shear force at the base of the structure at each time step is maximized under constraints on ground motion. Among computed critical accelerations (of each time step), the one which produces maximum internal shear force is selected. A numerical example presents to show the efficiency of critical excitation method in determining the maximum internal shear force and base moment under variety of constraints. The results show that these method can be used to compute the resonant earthquake which have large enough effective duration of earthquake strong motion (between 12.86 sec to 13.38 sec) and produce the internal shear force and base moment for specific column greater than the same value for selected earthquakes in constructing the critical excitation (for different cases about 2.78 to 1.29 times the San Fernando earthquake). Therefore, a group of them can be utilized in developing the response spectrum for design of special structures.

• International Journal of Advanced Culture Technology
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• 제7권2호
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• pp.83-92
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• 2019

The purpose of this study is to reduce the costs required to proactively prevent the turnover intention by the results of personality type of locus of control. which is the behavioral outcome of the members of the organization. Based on this problem consciousness, the present study focused on the personal characteristics of the members of the organization in the enterprise. Among the individual characteristics, the intentions, which are distinct from others, are called personality, Focusing on the locus of control among these types of characteristics of the organization members, the study about how these control positions affect their job involvement and their turnover intention. The results validated in this study are summarized as follows. Among the personality types of the organization's members, internals are found to have higher job involvement than externals. In addition, it was found that internals among the personality types of the members of the organization lower the meaning of turnover intention than external member. In order to overcome uncertain management environment and create and sustain a competitive advantage in the organization, management has a weight-oriented trend and Increasing job involvement in organizational members and lowering their turnover intention will lead to continued productivity, among other things, important management items that managers and managers should pursue. Given these aspects, it is deemed necessary to analyze the personality aspects of the members of the organization and to transform and manage a new management mindset that leads to the enhancement of the personality as an internal rather than an external one and the task immersion of the members of the organization based on it.

• 보건의료산업학회지
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• 제9권1호
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• pp.31-39
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• 2015

This study was undertaken to investigate the effectiveness of a hospital organization targeting both hospital administrative staff members and internal/external customers under a rapidly changing organizational environment, where the effect of creative behavior on passion about one's job was controlled with the participation of 55 people from two larger general hospitals, with 103 people from four general hospitals, with 51 people from eight regular hospitals. Thus, data from a total 209 people were collected. The creative behavior of hospital administrative staff members working for general hospitals and larger general hospitals significantly affected job engagement, showing that 'Relevant knowledge, maintaining status, and application appetite' were higher than the scores of 'new knowledge pursuit activities.' However, a weaker relationship between creative behavior and job engagement was found in medical institutions than for hospitals.

• 한국컴퓨터정보학회논문지
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• 제23권7호
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• pp.73-80
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• 2018

There are various organizations in modern society, in which people have direct and indirect relationships. Internal structure of these organizations can be analyzed by the relationships which are officially pressed on the media. However, this task will be difficult when the media information is strictly limited, though the necessity of analyzing organization structure remains. In this study, we try to estimate the influence of North Korea's core members by using PageRank centrality to supplement the limitation of previous SNA analysis methods. Experimental results show that we can show and predict NK's power shifts more efficiently.

• 한국게임학회 논문지
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• 제10권4호
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• pp.49-61
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• 2010

본 논문의 목적은 MMORPG의 길드 시스템이 사용자 커뮤니티 활성화에 영향을 미치는가를 실증분석하는 것이다. 이를 위해 본 논문은 온라인 게임 '군주'의 사용자 2,876명을 대상으로 설문조사를 실시, 이를 분석하였다. 연구 결과 MMORPG의 길드에 소속되어 있는 사용자는 소속되지 않은 사용자에 비해 사회적 지원이 더 활발하게 이루어지고 있음을 확인 할 수 있었다. 특히 길드 내적 사회적 지원이 길드 외적 사회적 지원보다 더 커뮤니티 활성화에 기여하는 것으로 드러났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.313-316
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• 2006

Externally prestressed structures have many advantages such as easy prestressing control and visible maintenance. Flexural strength of externally prestressed concrete members can be calculated by analysis of internal indeterminacy, which is different from internally prestressed concrete members. However, it needs nonlinear analysis considering member stiffness at strength limit state. Thus most of design codes proposed approximate methods which are empirical, based on test results. To reduce difference between accurate analysis and approximate design methods, many experiments and studies are continued. Since most of the experiments are single span beams. In order to adapt of continuous beam it needs further investigation for the continuous beam. In this study, we carried out externally prestressed 2-span concrete beam test to find out the flexural behavior and strength of externally prestressed concrete members.

• Smart Structures and Systems
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• 제15권3호
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• pp.523-541
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• 2015

Structural health monitoring of steel truss bridge based on changes in modal properties was investigated in this study. Vibration measurements with five sensors were conducted at an existing Warren truss bridge with partial fractures in diagonal members before and after an emergency repair work. Modal properties identified by the Eigensystem Realization Algorithm showed evidences of increases in modal damping due to the damage in diagonal member. In order to understand the dynamic behavior of the bridge and possible mechanism of those increases in modal damping, theoretical modal analysis was conducted with three dimensional frame models. It was found that vibrations of the main truss could be coupled internally with local vibrations of diagonal members and the degree of coupling could change with structural changes in diagonal members. Additional vibration measurements with fifteen sensors were then conducted so as to understand the consistency of those theoretical findings with the actual dynamic behavior. Modal properties experimentally identified showed that the damping change caused by the damage in diagonal member described above could have occurred in a diagonal-coupled mode. The results in this study imply that damages in diagonal members could be detected from changes in modal damping of diagonal-coupled modes.

• Structural Engineering and Mechanics
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• 제77권6호
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• pp.745-751
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• 2021

Concrete filled double skin tubular members (CFDST) consist of double concentric circular or square steel tubes with concrete filled between the two steel tubes. The CFDST members, having a hollow section inside the internal tube, are generally lighter than ordinary concrete filled steel tubular members (CFT) which have a solid cross-section. Therefore, when the CFDST members are applied to bridge piers, reduction of seismic action can be expected. The present study aims to investigate, experimentally, the behavior of CFDST stub columns with double concentric square steel tubes filled with concrete (SS-CFDST) when working under centric compression. Two test parameters, namely, inner-to-outer width ratio and outer square steel tube's width-to-thickness were selected and outer steel tube's width-to-thickness ratio ranging from 70 to 160 were considered. In the results, shear failure of the concrete fill and local buckling of the double skin tubes having largest inner-to-outer width ratio were observed. A method to predict axial loading capacity of SS-CFDST is also proposed. In addition, the load capacity in the axial direction of stub column test on SS-CFDST is compared with that of double circular CFDST. Finally, the biaxial stress behavior of both steel tubes under plane stress is discussed.

• 대한기관윤리심의기구협의회지
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• 제1권1호
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• pp.5-21
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• 2019

Purpose: Institutional review board (IRB) classifies risks of clinical trials into less than minimal risk, minor increase over minimal risk, and more than minimal risk. Based on classification and evaluation for risk, IRB decides whether permitting consent exemption or asking additional protection for clinical research subject or not. The purpose of this study is to analyze how IRB members evaluate minimal risk by sending questionnaire survey with 12 predetermined scenarios. Methods: IRB members and researchers (pediatrician, gastroenterologist, neurologist, and neurosurgeon) in 11 different hospitals were asked to answer survey questions via email or online. We analyzed the differences of answers among several subgroups in each predetermined scenarios. Result: Responders were 212 personnel(110 researchers and 102 IRB members) from 11 centers. There were significant differences between IRB members and researchers in response such as blood sampling, skin prick test, one time catheterization in a girl, spinal tapping in child, non-enhance MRI in child, non-enhance MRI with chrolal hydrate in a child, spinal tapping without anesthesia in adult, bioequivalence test, gastric endoscopy, and non-enhance CT. significant differences between medical IRB members and non-medical members were also revealed in one time catheterization in a girl, spinal tapping in a child, non-enhance MRI in a child, bioequivalence test. Depending on researchers' department, they responded differently in several questionnaires as well. Conclusions: We have found that IRB members and researchers evaluate the risks differently. Researchers compared to IRB members, medical IRB members compared to non-medical members answered less than minimal risk in many cases. In assessing and evaluating the risks associated with the study, medical IRB members answered predetermined scenarios as less dangerous compared to non-medical IRB members. Difference among researchers where also revealed significantly. Researchers answered predetermined scenarios as less dangerous compare to other department researchers, especially in predetermined scenarios containing procedures they are familiar with.

• 지식경영연구
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• 제22권3호
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• pp.1-16
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• 2021

공기업이 경영실적평가에 효과적으로 대응하고 지속적으로 발전하기 위해서는 내부성과관리가 필수적이다. 본 연구는 내부성과평가제도의 효과성과 수용성에 대한 구성원의 인식이 조직몰입에 미치는 영향을 확인함으로써, 효율적 성과관리에 대한 시사점을 모색하고자 하였다. 이를 위해 A 공기업 구성원 208명의 유효응답을 획득하고 다중회귀분석을 통해 가설을 검증하였다. 분석결과 내부성과평가에 대한 '성과평가효과성'과 '성과평가수용성'은 '조직몰입'에 긍정적 영향을 미치고 있지만, '성과보상차등'이 '조직몰입'에 미치는 영향은 유의하지 않았다. 또한 통제변수 중 '나이'와 '직군'은 '조직몰입'에 부(-)의 영향을 미치는 것으로 나타났다. 향후 일반화가 가능한 연구를 위해 다양한 공기업을 대상으로 한 추가연구가 필요할 것으로 판단된다.