• 한국생산제조학회지
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• 제26권4호
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• pp.436-440
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• 2017

This study evaluated the design and structural integrity of a three-axle bogie frame in a railway freight car through a numerical analysis and an experimental evaluation. A three-axle bogie frame, which supports the weight of the car body and load, is required to transport heavier cargo because two-axle vehicles have structural limitations. Therefore, this study performed a structural analysis and static load tests to evaluate the design and structural integrity of a three-axle bogie frame. The results obtained from the numerical analysis were compared to those of the experiments. For the bogie frame used in the experiments, a failure evaluation was performed using non-destructive methods. The numerical analysis and experimental evaluation were satisfactory for the structural integrity evaluation.

• 한국공간구조학회논문집
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• 제23권1호
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• pp.77-84
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• 2023

In this study, the performance evaluation of the RC frame specimen (RV2) which was strengthened by a steel frame and a steel damper with the lateral deformation prevention details proceeded. The comparison objects are bare frame specimen (BF), RV2 and AWD, where AWD is a specimen reinforced with steel damper and aramid fiber sheets. In the evaluation of envelope curve, stiffness degradation, and energy dissipation capacity, RV2 was evaluated to have excellent capacity as a whole. To evaluate the strengthening effect of the steel frame based on the maximum strength and energy dissipation capacity, it was evaluated to have a 38% of the RV2's capacity.

• 한국안전학회지
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• 제28권3호
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• pp.1-5
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• 2013

In order to evaluate fatigue endurance for an MTB(mountain bike) frame, FEM(finite element method) analysis was performed. For evaluating the fatigue endurance of the MTB frame, the S-N data for Al-6061 fillet weldment were compared with the stress analysis results through FEM analysis of the frame. Three loading condition, pedalling, horizontal and vertical loading conditions were considered for fatigue endurance evaluation. Horizontal loading(+1200 N) condition was found to be the most severe to the frame. The maximum von Mises stress of the frame under horizontal loading(+1200 N) condition was determined 294 MPa through FEM analysis of the frame. Conclusively, on the basis of fatigue strength of 200 MPa at the number of cycles of 50,000, the MTB frame has an improper safety factor of approximately 0.25, suggesting that this frame needs reinforcement.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.609-614
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• 2010

In this paper, the structural integrity and fatigue strength for the bogie frame of Monorail being developed in domestic was evaluated. Presently, the standard of evaluation for the bogie frame of monorail was not regulated. Therefore, the evaluation of the structural integrity and fatigue strength for the bogie frame was performed on the basis of the UIC 615-4 standard. The structural integrity of the designed bogie frame was evaluated by displacement and Von-Mises stress under each load conditions. And the fatigue strength was evaluated by combined main in-service load conditions specified at UIC 615-4 standard and it was compared with result of fatigue analysis using winLIFE v3.1 with the function of batch processing. The results shows that the structural integrity and fatigue strength of the designed bogie frame was satisfied, and the fatigue analysis using batch processing was more effective than conventional fatigue analysis using combined load conditions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.378-383
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• 2008

Bogie frame of the locomotive is an important structural member for the support of vehicle loading. A lot of study has been carried out for the prediction of the structural integrity of the bogie frame in experimental and theoretical domains. The objective of this paper is to estimate the structural integrity of the bogie frame. Strength analysis has been performed by finite element analysis. From these analysis, stress concentration areas were investigated. For evaluation of the loading conditions, dynamic stress were measured by using strain gage. It has been found that the stress and strain due to the applied loads were multi-axial condition according to the location of strain gage. The fatigue strength evaluations of the bogie frame are performed to investigate the effect of the multi-axial load through the employment of the critical plane approach.

• Structural Engineering and Mechanics
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• 제27권6호
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• pp.671-682
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• 2007

The probability and the reliability-based seismic performance evaluation procedure proposed in the FEMA-355F was applied to a reinforced concrete moment frame building in this study. For the FEMA procedure, which was originally developed for steel moment frame structures, to be applied to other structural systems, the capacity should be re-defined and the factors reflecting the uncertainties related to capacity and demand need to be determined. To perform the evaluation procedure a prototype building was designed per IBC 2003, and inelastic dynamic analyses were conducted applying site-specific ground motions to determine the parameters for performance evaluation. According to the analysis results, distribution of the determined capacities turned out to be relatively smaller than that of the demands, which showed that the defined capacity was reasonable. It was also shown that the prototype building satisfied the target performance since the determined confidence levels exceeded the objectives for both local and global collapses.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2004년도 춘계 학술대회 발표논문집
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• pp.235-238
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• 2004

Frame erasures cause speech quality degradation in wireless communication networks or packet networks. The degradation becomes worse when consecutive frame erasures occur. Speech coders have a frame erasure concealment(FEC) mechanism to compensate for frame erasures. It is meaningful to evaluate the performance of FEC mechanisms for frame erasures that occur in communications networks. In this paper, various frame erasures are designed. And the FEC algorithms of speech coders are evaluated and analyzed with the Perceptual Evaluation of Speech Quality(PESQ). It is found that the performances vary in accordance with frame erasure types, frame erasure rates, and utterance lengths.

• 한국철도학회논문집
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• 제8권4호
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• pp.321-329
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• 2005

This paper has established the strength evaluation procedure of the bogie frame for the Korean tilting train that is being developed in KRRI, In order to establish the strength evaluation procedure, firstly, the loading conditions imposed on the tilting train were investigated. In addition, the static and fatigue strength of the bogie frame has been evaluated. In order to derive the dynamic loads according to the carbody tilting, the load redistribution effect by carbody tilting, the unbalanced lateral acceleration effect by high-speed curving and the tilting actuator force effect have been considered. Multi-body dynamic analyses have been carried out to evaluate the tilting load cases and the strength analysis has been performed by finite element analyses. From this study, the structural safety of the bogie frame could be ensured.

• 한국콘텐츠학회논문지
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• 제18권3호
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• pp.354-360
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• 2018

정보통신기술의 발달로 최근 컴퓨터 기술의 발달은 교수자, 학습자들 모두에게 새로운 방식의 교육개념과 교육시스템의 도입을 촉진해왔다. 이에 본 연구는 21세기의 새로운 기술요구에 따라 강조되고 있는 인식론적 프레임(Epistemic Frame)에 대한 이론적 모형 구축과 이를 평가할 수 있는 핵심 평가문항을 구축함을 목적으로 한다. 구체적으로는 첫째, 인식론적 프레임 이론적 모형을 도메인 분석을 통하여 구축한다. 둘째, 구축된 이론적 모형의 구성요소들을 평가할 수 있는 평가요소들을 개발하고자 한다. 마지막으로 개발된 평가문항을 요인분석과 Cronbach's alpha분석을 통하여 타당도와 신뢰도를 평가하였다. 연구 결과로는 컴퓨터를 활용하여 학습할 수 있는 인식적 프레임의 이론 모형제시하고, 이를 평가할 수 있는 평가문항들의 타당도와 신뢰도를 실증적 통계적 분석을 통하여 결과를 제시하였다. 본 연구는 컴퓨터를 활용하여 다양한 영역에서 인식론적 프레임이 적용된 교육프로그램을 개발하는 연구자 및 실무자들에게 유용한 정보를 제공할 것으로 기대된다.

• 한국언론정보학보
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• 제71권
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• pp.274-298
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• 2015

이 연구는 프레임 개념과 편향성 개념을 통합적으로 연결해 재난 사고 뉴스의 정치사회적 의미를 해석했다. 국내 언론이 세월호 침몰 사고라는 특수한 재난 사고의 문제 정의, 원인 해석, 도덕적 평가, 그리고 사후 처방을 제시하는 과정에 어떤 프레임을 더 편향되게 배치했는지를 이론적으로 검정해 보았다. 또한 프레임의 편향성이 정치적 이념을 달리하는 보수 신문과 진보 신문 간에 어떤 차이가 있는지 비교 분석해 보았다. 내용 분석 결과를 제시하면 다음과 같다. 첫째, 세월호 사고 진단 프레임에서는 전체적으로 파편화>개인화>권위무질서>극화의 순으로 편향되어 있었다. <조선일보>는 파편화 편향성이, 한겨레는 권위무질서 편향성이 상대적으로 컸다. 둘째, 사고 평가에서는 책임 프레임>도덕적 프레임>문제 해결 프레임>사고 원인 프레임의 순으로 편향되어 나타났다. <조선일보>는 책임 프레임, 도덕적 프레임 편향적으로 사고를 평가했다. <한겨레>는 책임 프레임, 문제 해결 프레임 편향성이 두드러졌다. 셋째, 책임 소재 프레임에서는 정부>개인>조직의 순으로 편향되어 제시됐다. <조선일보>는 정부와 개인의 책임 편향성을 드러낸 반면에, <한겨레>는 상대적으로 정부에 책임을 더 강조하면서 조직에 대한 책임 편향성도 보였다. 넷째, 문제 해결 프레임에서는 전체적으로 주제적 프레임과 일화적 프레임 편향성이 엇비슷한 수준으로 나타났다. <조선일보>는 일화적 프레임으로, <한겨레>는 주제적 프레임으로 더 편향화하는 차이를 보였다. 세월호 사고의 평가와 해석에 대한 언론의 프레임 편향성과 함께 이념적 차이에 따른 언론 간의 편향성 차이를 사회적 맥락 차원에서 토론했다.