• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.481-484
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• 2011

최근 철도는 미래의 핵심교통수단이자 저탄소 녹색성장을 대표하는 교통수단으로 주목받고 있다. 그 중 자기부상열차는 바퀴 마찰에 따른 소음 진동 분진이 없는 차세대 교통수단이며, 이를 지지하는 구조물(교량)은 열차의 운행 안정성(동적거동)을 고려한 설계가 필요하다. 또한, 상부 구조물은 자기부상열차의 연행이동등분포하중을 지지하며, 이러한 하중조건을 갖는 차량이 운행할 때 상부 구조물은 설계기준사항들을 만족해야한다. 도시형 자기부상철도 토목구조물 설계기준에 의하면 도시형 자기부상철도의 운행 안정성(동적거동)을 평가하기 위한 항목들로 대상 구조물의 고유진동수, 승차감을 고려한 연직처짐 등이 요구된다. 따라서, 본 연구에서는 자기부상열차의 실 열차하중을 고려하여 연행이동등분포하중으로 철도교량의 동적거동을 검토하였으며, 설계기준을 적용하여 대상 철도 교량의 운행 안정성을 평가하였다.

• Journal of Biosystems Engineering
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• v.24 no.6
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• pp.523-530
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• 1999

자기공명영상 (MRI)기법은 최근에 그의 이용 분야가 식품공학 및 농학 분야까지 확대되고 있다. 이 연구에서는 MRI의 기본 원리를 알아보고 어떤 요인들이 자기공명영상의 명암을 결정하는지 알아 보았다. MRI를 이용하여 비파괴적인 방법으로 농축산물의 내부 구조 영상을 얻고 이로부터 토마토의 내부 공동, 감자의 공동병, 사과와 파파야의 멍, 버찌씨의 유무, 망고와 감자의 벌레에 의한 손상, 망고와 마늘의 내부 결함, 키위의 성숙도에 따른 변화, 그리고 소고기의 내부 구조 둥을 판별할 수 있음을 알아 보았으며 농축산물의 품질을 결정짓는 이러한 내부 요인들이 어떻게 자기공명영상을 형성하는지 알아 보았다. 대상 시료에 따라 적당한 자기공명영상 인자(TR과 TE)를 선택하여야 한다. 또한 특정 인자를 강조하기 위해서는 최적의 자기공명영상 인자를 선택하여야 한다.

• Proceedings of the KSMRM Conference
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• 1999.11a
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• pp.17-18
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• 1999

최근까지 복부 자기공명영상은 간의 국소병변의 특성을 규명하는 데 가장 많이 사용되어 왔다고 할 수 있다. 그러나, 자기공명영상의 기법과 장비의 발달로 인해 그 적응증이 더욱 확대되어 가는 추세에 있고 , 특히 자기공명담췌관촬영술의 도입과 발전은 복부 자기공명영상의 적응증을 한층 넓히는 데 크게 기여하고 있다. 이와 함께, 2차원 또는 3차원 경사에코기법과 조영제를 병용하여 호흡정지 상태에서 자기공명혈관촬영상을 얻을 수 있게 되어 자기공명담췌관촬영술과 혈관촬영술을 복합하여 다양한 담췌관질환을 평가하는 데 이용하는 빈도가 증가하고 있다. 이 강의 에서는 최근에 널리 사용되는 자기공명담췌혈관촬영술 또는 역동적 역상과의 복합적 사용의 유용성을 돌아보고자 한다.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.267-280
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• 2016

The purpose of this study was to examine the effects of adolescent victimization on human rights consciousness and the mediating effects of depression and evaluation on their own human rights among adolescents. A total of 3,662 middle school student data from '2014 Korean Children and Youth Human Rights Survey' were used for the study. This study analysed a hypothesized research model using structural equation modeling. The main findings on structural model are as follows: First, victimization did not have a direct influence on human rights consciousness but had an indirect effect through a mediating role of evaluation on their own human rights. Secondly, victimization were related to human rights consciousness through double mediating paths of depression and evaluation on their own human right. Finally, human rights education, a control variable, had an indirect effect on human rights consciousness through self-evaluation on human rights. The results of this study suggest some implications for practical intervention and further research on the relation between adolescent victimization and human rights consciousness.

• Korean journal of communication and information
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• v.36
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• pp.254-286
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• 2006

The purpose of the present study is to examine how visitors of personal web sites evaluate self presentation styles. We hypothesized that visitors' gender, self construals, and self esteem would influence the evaluation (likeability and perceived competence) of the self presentation styles (bragging or positive presentation). The hypothesized models were tested with structural equation modeling. Gender differences among the constructs were also examined through latent mean analysis. The results revealed that females tended to have higher interdependent self construal than males. And the male and the female students showed higher likeability toward the self presentations of the other gender. Regarding perceived competence, women and men perceived the other gender more competent, and especially, women perceived men's bragging presentation more competent. Self construals and self esteem, however, did not show any significant effects, which were inconsistent with the results of the previous studies conducted with offline self presentation styles. One of the main implications of this study is that visitors' gender, among other things, is the most infueltial factor in perceiving and evaluating others' self presentation through personal web sites.

• Investigative Magnetic Resonance Imaging
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• v.5 no.2
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• pp.98-107
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• 2001

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.67-73
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• 2020

In this study, the self-healing performance of mortar beams containing self-healing materials was evaluated through experiments. Normal mortar beams and self-healing mortar beams were used In the experiments. The self-healing performance was evaluated by comparing the mortar compressive strength, member strength, and self-healing effects of cracks. The experimental results showed that the compressive strength of mortar containing self-healing material was smaller than that of normal mortar, but the ratio of 118 days compressive strength to 28 days compressive strength was the same. The member strength tended to increase with increasing curing period. In normal mortar specimens, the member strength did not recover even if the curing period increased, but the strength of the self-healing mortar specimens tended to recover as reaction products were produced. The crack width tended to decrease after the healing periods in both specimens, but the reaction product was observed only in the self-healing mortar specimens.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.5A
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• pp.441-450
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• 2006

Recently, with the exponential growth of the number of Internet users, IP traffic which occupies more than 90 percent of the entire Internet traffic affects significantly to the performance of networks. Therefore, the design of the self-similar traffic generator reflected the feature of IP traffic is very important to design the networks efficiently and evaluate the performance of it correctly. In this paper, we design the self-similar traffic generator using OPNET. In order to implement the self-similar characteristics, ON-OFF sources with Pateto distribution are employed and aggregated. The designed self-similarity traffic generator is evaluated and verified with R/S plot, variance time(VT) plot under the various offered loads and the number of sources. It is expected that the designed self-similar traffic generator can be put to practical use when wire or wireless networks is designed and verified as well as it can be useful to decide the specific parameter value for Internet traffic modeling.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.701-711
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• 2022

This study tried to examine the relationship between superior leadership and emotional support from co-workers on task performance through performance evaluation fairness and self-efficacy in order to find factors that affect the task performance of a company in an uncertain market environment. For this purpose, 500 copies of questionnaire data were collected from corporate employees, and the research hypothesis was verified using Smart PLS 3.0. As a result of the study, superior leadership and emotional support from co-workers showed a positive (+) effect individually on the fairness of employee performance evaluation, Performance evaluation fairness showed a positive (+) effect on self-efficacy. Through this study, it was found that the fairness and self-efficacy of the performance evaluation accepted by employees affects work performance, providing a theoretical foundation for subsequent researchers. Practical implications are suggested to inspire employees to take on a challenge by managing them properly. In future research, based on the results of this study, various studies are needed on the factors that an organization must have for task performance.

• Journal of the Korean Chemical Society
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• v.65 no.6
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• pp.455-467
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• 2021

The purpose of this study was to investigate the impact of negotiation-based peer and self-assessment activities on science-gifted students' modeling and students' perceptions of the impact of these assessment activities on modeling. For this purpose, 92 students in the 11th grade of a science high school, in a metropolitan city, were selected to conduct peer assessment, self-assessment, and science writing activities with four topics of Advanced Chemistry. The students' modeling was analyzed in terms of 'structuring scientific concepts', 'logic', 'multiple representations' and 'communication'. Based on the results, the mean scores of modeling increased for each element of evaluation according to the progress of assessment activities. Students' responses in the survey and interviews showed that students perceived the results of student assessment activities as valid, students also recognized the benefit of these assessment activities by referring to the assessment results before their next writing assignment.