• 한국철도학회논문집
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• 제5권2호
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• pp.125-132
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• 2002

As the public use part of the railway and the road, the railway crossing is important to work properly by two transportation means. Also, It is important to provide the good face of friction on the railway crossing in aspect of protecting the railway crossing accident. Lately, the material of railway crossing panel is the wood, the asphalt, and the steel. As they have a various fault, it was studied to analyze the structural action of the new material, rubber panel. This paper analyzed eigenvalue, stress and displacement by truck passing weight, thermal stress and train moving weight, using the Finite Element Method model

• Nuclear Engineering and Technology
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• 제50권7호
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• pp.1099-1105
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• 2018

How to choose defaults in risk-informed regulations depends on the conservatism implicated in regulatory defaults. Without a universal agreement on the approaches dealing with the conservatism of defaults, however, the desirability of conservatism in regulatory risk analyses has long been controversial. The opponent views it as needlessly costly and irrational, and the proponent as a form of protection against possible omissions or underestimation of risks. Moreover, the inherent ambiguity of risk makes it difficult to set suitable defaults in terms of risk. This paper, the extension of the previous work [1], focuses on the effects of different levels of conservatism implicated in regulatory defaults on the estimates of risk. According to the postulated behaviors of regulated parties and the diversity of interests of regulators, in particular, various measures for evaluating the effect of conservatism in defaults are developed and their properties are explored. In addition, a simple decision model for setting regulatory defaults is formulated, based on the understanding of the effect of conservatism implicated in them. It can help decision makers evaluate the levels of safety likely to result from their regulatory policies.

• International Journal of Internet, Broadcasting and Communication
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• 제14권2호
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• pp.119-128
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• 2022

Recently, due to the development of related technologies for autonomous vehicles, driving work is changing more safely. However, the development of support technologies for level 5 full autonomous driving is still insufficient. That is, even in the case of an autonomous vehicle, the driver needs to drive through forward attention while driving. In this paper, we propose a method to monitor driving tasks by recognizing driver behavior. The proposed method uses pre-trained deep convolutional neural network models to recognize whether the driver's face or body has unnecessary movement. The use of pre-trained Deep Convolitional Neural Network (DCNN) models enables high accuracy in relatively short time, and has the advantage of overcoming limitations in collecting a small number of driver behavior learning data. The proposed method can be applied to an intelligent vehicle safety driving support system, such as driver drowsy driving detection and abnormal driving detection.

• Smart Structures and Systems
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• 제29권3호
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• pp.421-431
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• 2022

Concrete slab cracks monitoring of modern high-speed railway is important for safety and reliability of train operation, to prevent catastrophic failure, and to reduce maintenance costs. This paper proposes a curvature filtering improved crack detection method in concrete slabs of high-speed railway via graph-based anomalies calculation. Firstly, large curvature information contained in the images is extracted for the crack identification based on an improved curvature filtering method. Secondly, a graph-based model is developed for the image sub-blocks anomalies calculation where the baseline of the sub-blocks is acquired by crack-free samples. Once the anomaly is large than the acquired baseline, the sub-block is considered as crack-contained block. The experimental results indicate that the proposed method performs better than convolutional neural network method even under different curvature structures and illumination conditions. This work therefore provides a useful tool for concrete slabs crack detection and is broadly applicable to variety of infrastructure systems.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3320-3325
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• 2023

The scaled water-cooled Reactor Cavity Cooling System (RCCS) experimental facility reproduces a passive safety feature to be implemented in Generation IV nuclear reactors. It keeps the reactor cavity and other internal structures in operational conditions by removing heat leakage from the reactor pressure vessel. The present work uses Flownex one-dimensional thermal-fluid code to model the facility and predict the experimental thermal-hydraulic behavior. Two representative steady-state cases defined by the bulk volumetric flow rate are simulated (Re = 2,409 and Re = 11,524). Results of the cavity outlet temperature, risers' temperature profile, and volumetric flow split in the cooling panel are also compared with the experimental data and RELAP system code simulations. The comparisons are in reasonable agreement with the previous studies, demonstrating the ability of Flownex to simulate the RCCS behavior. It is found that the low Re case of 2,409, temperature and flow split are evenly distributed across the risers. On the contrary, there's an asymmetry trend in both temperature and flow split distributions for the high Re case of 11,524.

• Advances in aircraft and spacecraft science
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• 제10권6호
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• pp.545-554
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• 2023

The widespread introduction of unmanned aircrafts has led to the understanding of the need to organize a common information space for manned and unmanned aircrafts, which is reflected in the Russian Unmanned aircraft system Traffic Management (RUTM) project. The present article deals with the issues of spatial information database (DB) organization, which is the core of RUTM and provides storage of various data types (spatial, aeronautical, topographical, meteorological, vector, etc.) required for flight safety management. Based on the analysis of functional capabilities and types of work which it needs to ensure, the architecture of spatial information DB, including the base of source information, base of display settings, base of vector objects, base of tile packages and also a number of special software packages was proposed. The issues of organization of these DB, types and formats of data and ways of their display are considered in detail. Based on the analysis it was concluded that the optimal construction of the spatial DB for RUTM system requires a combination of different model variants and ways of organizing data structures.

• 한국화재소방학회논문지
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• 제20권3호
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• pp.1-8
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• 2006

본 논문의 목적은 Ethyl Benzene 플랜트의 공정에서 과압 현상이 Column 상부의 반응폭주 및 화재 폭발의 원인이 되기 때문에 안전장치시스템의 신뢰도가 압력방출밸브가 요구하는 안전건전성수준으로 설계되어 있는지를 정량적으로 분석한 것이다. 압력방출밸브의 요구시 실패확률은 일반신뢰도 자료 조사결과를 근거로 하여 안전장치시스템에 대한 안전건전성수준의 목표등급을 SIL3으로 설정하였고, 이에 대한 PFD를 1.00E-3에서 1.00E-4로 결정하였다. 신뢰도 모델의 구축 및 결함수 분석기법을 이용하여 SIS의 요구시 실패확률에 대한 정량화를 수행한 결과 SIS에 대한 PFD는 Benzene Prefractionator Column, Benzene Column, EB Column에 대해 각각 8.97E-04, 5.37E-04, 5.37E-04로 계산되었다. 따라서 SIS의 신뢰도가 SIL3 등급에 요구되는 안전건전성수준으로 설계되어 있다고 판단되며 컨트롤밸브에 대한 6개월 주기의 Partial Stroke Test가 수행될 경우 각 Column의 SIS는 약 $22{\sim}27%$의 신뢰도 향상이 기대된다.

• 한국재난정보학회 논문집
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• 제19권1호
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• pp.161-172
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• 2023

건설근로자에게 강의식으로 전달하는 안전교육은 집중도와 몰입도에 한계가 있으므로 전달력과 흥미가 떨어진다. 교육을 통하여 불안전한 행동을 개선하고, 안전사고를 예방하기 위해서는 체험식 교육으로 패러다임을 전환할 필요가 있다. 연구목적: 체험식 안전교육은 건설근로자가 위험을 더 빠르게 인지하고, 응급대처 능력향상과 사전·사후 학습전이 효과성을 검증하므로 건설근로자 사고 예방에 기여하고, 체험교육이 건설근로자 안전한 행동 유도에 미치는 영향 연구가 목적이다. 연구방법:실제 건설 현장과 동일 작업환경으로 구성된 체험시설을 경험한 종사자들의 설문으로 안전체험교육 사전·사후에 대한 의견조사와 학습전이 성과에 대해서 조작적 정의와 변수측정도구를 계획하고, 연구가설을 설정하였다. 연구결과: 구조방정식 모형을 통하여 경로분석 하였으며, 베이지안 이론과 MC 시뮬레이션 분석법으로 척도목표 기술통계량 및 척도입력 기술통계량에서 의도된 안전(A), 불안전(B)의 하위영역 비(非) 체험 교육, 체험식 교육의 평균, 표준편차, 최소·최대 값을 통해서 건설근로자 행동 변화를 확인하고 가설을 증명하였다. 결론: 건설근로자들에게 참여동기가 유발되어야 교육의 효과와 산업재해가 감소된다.

• 대한인간공학회지
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• 제26권2호
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• pp.45-59
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• 2007

The operating tasks of overhead crane have caused undue stress to the operators from physical, mental, and environmental workload. Existing workload assessment models for musculoskeletal disorders such as OWAS, RULA, and QEC have limited applicability to the crane operating tasks because they focus mainly on physical factors and do not consider the relative importance of each factor. The present study was to develop a workload assessment model customized to overhead crane operation, following a systematic process: (1) analyzing task characteristics, (2) selecting workload factors, (3) developing assessment methods, (4) establishing action levels, and (5) computerizing the assessment model. Based on literature review, worksite survey, and focus group interview, 4 physical factors (awkward posture, static posture, repetitive motion, and excessive force), 6 mental factors (visual demand, auditory demand, task complexity and difficulty, time urgency, work schedule related stress, and safety related stress), and 4 environmental factors (noise, vibration, dust, and temperature) were selected and their rating scales and relative weights were determined. Then, based on the workload assessment results of 8 overhead cranes operated at different workplaces, the action levels of each factor category were established. Finally, the crane operation assessment model was computerized for effective analysis and report preparation. The present approach is applicable to develop a customized workload assessment model for an operating task under consideration.

• International Journal of Computer Science & Network Security
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• 제21권3호
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• pp.21-30
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• 2021

Economic transformations have led to an increase in the role of creative assets and their central role in public life. Changes in creative activity have led to a change in the organization of the work of institutes engaged in the training of specialists, in particular teachers of labor education. Methods and approaches to training determine the development of creative industries, being the basis for models of professional training of future teachers of labor training. The purpose of an article was to develop a modern model of professional training of future teachers of labor training based on the concept of creative economy. The methodology is based on the concepts of holistic craft and creative economy. Based on the integration of pedagogical learning models "Craft as design and problem-solving", "Craft as skill and knowledge building", "Craft as product-making" and "Craft as self-expression" developed and experimentally confirmed the conceptual model of professional training of future teachers of labor training. The proposed model forms a practitioner with professional, technical, digital and creative skills who is able to transfer the experience to students. The training course "Creativity and creative thinking" has been developed. The model provided for the development of a course based on the strategy of developing professional creativity, flexibility, improvisation, openness, student activity, joint practice, student-oriented approach. The practical value implies the adaptation of the developed model of professional training of future teachers of labor education during the training of teachers in higher education, which is confirmed in the experiment.