• 한국지반신소재학회논문집
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• 제20권4호
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• pp.151-163
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• 2021

본 논문에서는 초속경 복합매트를 이용하여 비탈면 보강 시 비탈면 안정해석에 대한 내용을 다루었다. 최근 지구온난화에 따른 기상이변으로 태풍, 집중호우 등에 의해 철도 성토 노반 비탈면 유실로 열차 운행이 제한되고 있다. 또한 복구 비용보다 피해액이 증가하고 있으며 유실로 인한 작업환경 저하로 작업자들의 안전이 우려되고 있다. 이를 위해 기존에 다양한 비탈면 보호공법이 개발되었지만 철도 현장 특성상 중장비의 투입이 곤란하여 적용이 곤란한 실정이다. 따라서 본 연구에서는 시공기면 확보가 용이하여 시공성 및 작업 안정성을 증대시키며 집중호우 시 재유실 방지 및 식생생장을 원천적으로 차단하여 유지보수 비용을 절감할 수 있는 초속경 복합매트를 적용한 비탈면 안정해석을 실시하였다. 해석 결과 초속경 복합매트의 적용시 안전율 증가가 확인되었지만 초속경 복합매트의 두께에 따른 안전율 증가는 미미한 것으로 확인되었다.

• Wind and Structures
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• 제35권4호
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• pp.269-285
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• 2022

The pressure-mitigating effects of a high-speed train passing through a tunnel with a partially reduced cross-section are investigated via the numerical approach. A compressible, three-dimensional RNG k-ε turbulence model and a hybrid mesh strategy are adopted to reproduce that event, which is validated by the moving model test. Three step-like tunnel forms and two additional transitions at the tunnel junction are proposed and their aerodynamic performance is compared and scrutinized with a constant cross-sectional tunnel as the benchmark. The results show that the tunnel step is unrelated to the pressure mitigation effects since the case of a double-step tunnel has no advantage in comparison to a single-step tunnel, but the excavated volume is an essential matter. The pressure peaks are reduced at different levels along with the increase of the excavated earth volume and the peaks are either fitted with power or logarithmic function relationships. In addition, the Arc and Oblique-transitions have very limited gaps, and their pressure curves are identical to each other, whereas the Rec-transition leads to relatively lower pressure peaks in C_Pmax, C_Pmin, and ΔC_P, with 5.2%, 4.0%, and 4.1% relieved compared with Oblique-transition. This study could provide guidance for the design of the novel railway tunnel.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.247-253
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• 2004

For the preparation of KTX operation and electrifying the conventional line, many accidental fatalities were occurred in recent year. In order to improve track worker safety as low as possible, risk assessments are carried out in this study. As an input of risk assessment 5-year accident data were analyzed into frequency and fatality. As a result risk of track worker based on equivalent fatality is derived.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.511-518
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• 1999

Though not very often, a train accident can cause large number of fatality. As a result, public concern about its safety is increasing nowadays. Tn this paper, the structural crashworthiness of Korean High Speed Train trailer was examined through FE analysis. Crash analyses on energy absorbing part and safety zone were carried out to determine each section force. Rollover analysis was performed to observe the amount of intrusion in the passenger's area in case of rollover accident.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.307-311
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• 2007

In the case of the railway bridges, uplift forces were occurred at the edge of the segments when vehicular loads were applied. These forces made the compressive and tensile forces occur in the fastening system. Therefore, the structural analysis was performed to investigate the safety of fastening system which was modeled as one directional spring element. In this case, the stiffness of the spring element was obtained from experimental study which was conducted by compressive load. For that reason, to perform rational and exact structural analysis, the translational stiffness of the fastening system obtained from the experimental study applied the tensile load and the rotational stiffness should be considered because it was occurred the tensile force as well as the compressive force in fastening system. In this study, an elastic and inelastic experimental study was performed for six specimens. The translational stiffness along the vertical axis of rail and the rotational stiffness along the strong axis of rail were investigated. Also structural behavior of the fastening system was analyzed.

• The Journal of Asian Finance, Economics and Business
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• 제9권9호
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• pp.271-281
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• 2022

The objectives of the research are to study the effects of emotional intelligence (EI), reward management (RM), and occupational health and safety (OHS), on employee performance (EP) within a Thai motor service and repair firm. Starting in January 2022 through the end of March 2022, the researchers used simple random sampling techniques to select 88 employees for the case study. The research instrument was a questionnaire with an IOC value between 0.67-1.00 and a reliability value α of 0.78. Survey participants were asked to contribute their opinions to a five-level opinion survey which was hosted on Google Forms. Descriptive statistics analysis (mean and standard deviation) and multiple linear regression analysis were done using SPSS for Windows version 21. The results showed that employee opinions concerning EI, RM, OHS, and EP were at a high level, with the three hypotheses testing showing statistical significance (p ≤ 0.01). The decision coefficients (R²) all revealed relationship strength with RM = 0.861, OHS = 0.853, and EI = 0.731.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.744-747
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• 2004

This paper presents a strength evaluation of a tilling bogie frame for the Korean tilting train, The tilting bogies of the tilting train are subjected to different loading conditions compared with the bogie of the conventional railway vehicles because of the carboloy tilting on curves. We classified the load cases as two categories such as non-tilting case and tilting case. For the two categories. we have carried out structural analysis of the bogie frame to evaluate the strength of the frame. And then, we modified the shape and thickness for the weak areas of the bogie frame to ensure structural safety.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.577-583
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• 2007

In railway business plan, operations require a strategic and sustained level of planned investment to ensure assets are fit for purpose over the whole of their planned life. Therefore it is essential that operator can confidently plan and predict capital investment requirements over a number of years. This research addresses that how the London Underground apply a systematic risk based approach to their health and safety planning and investment decision making. Through this case study, we investigate the elements of management system that includes arrangements for the ongoing identification of hazards, assessment of risks and the implementation necessary control measures. Risk based business planning processes are also addressed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.311-319
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• 2011

Track accompanies the process that track alignment by traffic loads is changed. A change of track alignment affects the running safety and riding comfort of train. This is called a track irregularity. The most important task in maintaining the track is to manage these track irregularity within quality parameters. Today, track maintenance of urban transit is enforcing immediate maintenance about section exceeding a safety standard by applying track recording data got through Integrated Measurement. This method is advantage of being easy of the maintenance assesment in case of the running safety, but is disadvantage of being difficult in case of the riding comfort of train. In this study, we propose track irregularity deviation of each track system depending on the time series and present about utilization plans of the Track Irregularity Progress Rate.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1998-2004
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• 2003

Numerical study were performed to analyze for fire safety in railway tunnel with forced ventilation vents. For the condition of train fires with heat release rate of 30 MW, unsteady three dimensional analysis were carried out to investigate the effects of smoke movements, the heat transfer and $CO_2$ concentrations and in double track tunnel with two vents. Among three operation modes of forced ventilations at two vents, the exhaust-exhaust mode of the vent represents the best performance for the evacuation of passengers to avoid the fire.