• 한국산업보건학회지
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• 제33권2호
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• pp.188-205
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• 2023

Objectives: Methanol poisoning accidents in smartphone parts manufacturing facilities were analyzed using a systemic accident analysis method, and the necessity and possibility of the application of this systemic method in the field of occupational health were reviewed. Methods: A STAMP model for accident analysis was created based on the previously published literature. CAST analysis was performed to find the causal factors of the components and between the components. Results: The STAMP model visually showed the abstract and complex system control structure. The CAST analysis results could include all the causal factors from the previously published literature, and presented them holistically. Additional causal factors that were not presented in the literature were found. Conclusions: The holistic accident analysis results in this study will be helpful to establish comprehensive measures to prevent methanol or other chemical poisoning accidents. Therefore, it will be necessary to use systemic accident analysis methods in the field of occupational health.

• 한국안전학회지
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• 제38권3호
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• pp.51-60
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• 2023

Investigation of the cause of the relatively recent building collapse accident in Gwangju revealed a lack of awareness about the safety of the dismantling construction system among stakeholders, in the form of issues such as illegal subcontracting, unauthorized design changes, and insufficient safety supervision. This study was conducted to analyze the safety interactions between the building dismantling construction system and the involved stakeholders and to propose ways to prevent accidents in related institutions and workplaces. AcciMap and STAMP-CAST analysis methods were used to evaluate safety interactions among the various stakeholders participating in building demolition work. Analysis results revealed that the collapse accident during the dismantling work was caused not only by structural causes occurring in the construction stage, but also by various causes throughout the system, such as the dismantling plan preparation stage and the construction permit stage. The results also revealed the need for proper implementation of safety control measures by various stakeholders to prevent collapse accidents during dismantling construction.

• 한국안전학회지
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• 제37권5호
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• pp.42-55
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• 2022

In this study, an accident at an in-house maintenance subcontractor of a manufacturing company was analyzed using representative systemic analysis methods, and the results were compared to determine the socio-technical and organizational structure causal factors. Systemic accident analyses were performed using AcciMap, STAMP-CAST, and a method that utilizes work processing procedures. The causal factors derived from the three methods were classified according to HFACS classification criteria. AcciMap and STAMP-CAST analyses were able to derive legal problems and defects in organizational structure between the company and the subcontractors. The method that utilized the work processing procedures drew the most causal factors of the three methods but showed some limitations in deriving legal and facility-related problems. Most of the causal factors identified through the systemic methods could be classified according to the HFACS classification criteria, except for the legal and organizational structure matters. Socio-technical and organizational problems with a holistic perspective of the company and subcontractors could be found using systemic analysis methods. However, it is necessary to conduct analysis using various methods in order to derive more comprehensive measures to prevent accidents because each analysis method showed some limitations in the derivation or expression of some causal factors. The results of this study can be helpful in selecting and using an appropriate method for accident analysis.

• 한국안전학회지
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• 제36권4호
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• pp.62-70
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• 2021

Representative systematic accident analysis methods proposed so far include AcciMap, STAMP, and FRAM. This study used these three techniques to analyze a fire accident case that occurred during routine manufacturing work in a domestic chemical plant and compared the results. The methods used different approaches to identify the cause of the accident, but they all highlighted similar causal factors. In addition to technical issues, the three accident analysis methods identified factors related to safety education, risk assessment, and the operation of the process safety management system, as well as management philosophy and company culture as problems. The AcciMap and STAMP models play complementary roles because they use hierarchical structures, while FRAM is more effective in analyses centered on human and organizational functions than in technical analyses.

• 정보처리학회논문지D
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• 제8D권2호
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• pp.132-144
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• 2001

방송환경은 서버(server)와 클라이언트간 대역폭이 서버에서 클라이언트쪽으로는 크고 클라이언트에서 서버쪽으로의 대역폭은 상대적으로 많이 작은 비대칭적(asymmetric) 특수한 환경이다. 또한 대부분의 방송 환경 응용시스템들은 클라이언트측에서 발생한 주로 주식 데이터, 교통 정보와 새로운 뉴스와 같은 여러 가지 다양한 정보를 검색하는 읽기전용 즉 질의 거래들을 허락한다. 그러나, 기존의 여러 가지 동시성 제어 기법들은 이러한 특수성을 고려하지 않음으로써 꽤 높은 데이터 경쟁 상태의 방송 환경에 적용될 때 성능 감소가 일어난다. 이 논문에서는 방송환경에서 가장 적절한 OCC/2VTS(Optimistic Concurrency Control based on 2-Version and TimeStamp)를 제안한다. OCC/2VTS는 캐쉬 내에 두 버전을 사용함으로써 타임스탬프 기법으로 클라이언트가 질의 거래를 자체 해결 할 수 있도록 하였다. 질의 거래 시작 후 2번의 무효화 방송을 통해 읽기 연산 대상 데이터 항목의 값이 바뀌지 않는다면 질의 거래가 갱신 거래의 완료와 상관없이 무사히 완료된다. 그 결과 첫째, 서버에게 완료 요구를 위해 정보를 보내는 기회가 감소하고 무효화 보고서 내에 갱신된 최신의 값을 포함하여 클라이언트들에게 방송함으로써 최근 데이터 값을 서버에게 요구하는 기회를 줄여 비대칭적 대역폭을 효율적으로 활용한다. 둘째, 질의 거래의 완료율을 최대한 높여 처리율을 향상시킨다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2007년도 춘계 학술대회논문집
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• pp.153-158
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• 2007

Since the introduction of Nanoimprint in the mid-1990s, Nanoimprint lithography, a low-cost, non-convential method, has been the dominant lithography technology that guarantees high-throughput patterning of nanostructures. Based on the mechanical embossing mechanism, Nanoimprint lithography creates the nanopatterns on the polymer material cast on the substrate. In essence, the process needs nanofabrication equipment for printing with the adequate control of temperature, pressure and control of parallels of the stamp and substrate. This article introduce the possibility and reality of the thermal control on the hot plate using a CFD code. Numerical computation has been conducted for assessing the feasibility of a hot plate($120{\times}120\;mm2$). PID control is adopted to ensure high temperature uniformity in several zones. Parallel experiments have also been performed for verifying thermal performance. Not only show the results the optimum number of thermocouples related to controllers but also suggest that the thermal simulation using a CFD code would be an alternative method to design and develop the thermal control equipment in the financial aspect.