• 한국산학기술학회논문지
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• 제16권5호
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• pp.3071-3080
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• 2015

철도를 통한 승객 및 화물 운송의 수요가 증대함에 따라 철도 교통량 및 혼잡도가 증가하여 이에 따른 사고발생 가능성의 상승과 승객서비스 품질의 저하가 중요한 문제로 부각되고 있다. 이러한 문제들에 대한 해결책의 하나로 철도운영에 이용되는 통신서비스망의 통합을 통한 망의 고품질화가 최근에 많은 주목을 받게 되었다. GSM-R이 그러한 요구에 부응하는 유럽에서 개발된 통합 철도통신망인데, 망 자체의 속도 제한 때문에 다양하고 고품질이 요구되는 철도통신 서비스를 제공하는 데에는 제약이 있음이 알려져 있다. 이에 국내에서는 차세대 통신수단인 LTE 기반의 첨단 철도 통합무선망 구축에 관한 연구가 진행 중에 있다. 하지만 철도 통합무선망 자체에 대한 구축이 이루어진다 해도, 통합 통신망을 운영하고 관리하는 시스템이 필요한데 관련 연구가 미흡하다. 본 연구에서는 구축되는 철도 통합무선망을 위한 망의 운영관리 시스템에 대해 연구하는 것이 목표이다. 이를 위해 모델 기반 접근법을 통해 통신망 운영관리 시스템에 대한 개념설계를 수행하였다. 운영관리 시스템 설계에 있어서 먼저 운영관리의 개념을 명확하게 하는 것이 중요하기 때문에, 유스 케이스 다이어그램을 통해 시스템 컨텍스트 모델을 생성하였다. 또한 운영관리 개념의 명확성을 확보하기 위해서 모델링 표준언어인 SysML을 사용하여 운영 시나리오 모델을 생성하였다. 계속해서 SysML 모델들을 EFFBD 모델로 변환한 후 모델 시뮬레이션 및 검증을 수행하였다. 따라서 본 논문에서 보고된 연구 결과는 향후 운영관리 시스템의 개발 단계에서 상세설계를 진행할 때 기본 토대로 활용될 수 있다.

• 한국철도학회논문집
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• 제10권4호
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• pp.438-443
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• 2007

This paper proposes an integrated SE process for the development of railway systems with safety assessment included. Although the safety assessment process must be performed with SE process properly with good coordination, the interfaces between the two processes have not been clear. Thus, in many of safety critical system developments in Korea, it is difficult to assess safety in proper development phase. The process model proposed in this paper is based on both the concept of system life cycle and the repetitive use of SE process. In each of development phases, appropriate safety assessment methods are described. Also the evaluation of the integrated system incorporating safety factors is described. The resultant process model is expressed by the Enhanced Functional Flow Block Diagram (EFFBD) using a CASE tool. The model also allows timeline analysis for identifying activity flow and data flow, resulting in the effective management of process. In conclusion, the integrated process enable both the SE process and safety assessment process to cooperate with each other from early development phase throughout the whole system life cycle.

• 플랜트 저널
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• 제13권2호
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• pp.39-45
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• 2017

본 논문은 시스템엔지니어링기법을 이용하여 해양플랜트 산업의 소형 유틸리티 장비의 입찰단계에서 사용가능한 FEED 검증 수행모델에 대한 연구이다. 현재 국내 해양플랜트 기자재산업계는 해양플랜트에 진출하면서 프로젝트 수행에 따른 재정적 위험에 직면한 상태이며, 그 주요한 원인으로 기자재업체의 발주처(COMPANY 또는 EPC: Engineering, Procurement and Construction) 로부터 제공받은 FEED 결과물에 대한 검증능력부족으로 조사되었다. 이에 요구사항 분석, 기능, 성능분석 및 물리적아키텍처 구축프로세스를 순차적으로 적용하는 시스템 엔지니어링 기법을 간략화 한 FEED 설계 검증방법을 제안하고 이를 소형 유틸리티 장비(Air Compressor)를 대상으로 기존의 경험에 의존한 검증방법과 개발한 FEED 검증 모델을 적용한 결과를 비교함으로써 개발된 모델의 사용적정성을 검증하였다.

• 한국산업융합학회 논문집
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• 제22권6호
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• pp.785-795
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• 2019

This paper is a study on the modeling of the quantity estimation model for offshore plant Material handling equipment in FEED(Front End Engineering Design) verification stage using system engineering approach which is an engineering design methods. The relevant engineering execution procedure is not systemized although the operation method and Material handling equipment selection with weight and space constraints is a key part of the FEED. Using the system engineering process, the stakeholder requirements analysis process, the system requirements analysis, and the final system architecture design were sequentially performed, and the process developed through the functional development diagram and Requirement traceability matrix (RTM) was verified. In addition, based on the established process, we propose a Material handling quantity estimation model and Quantity calculation verification Table that can be applied at the FEED verification stage and we verify the applicability through case studies.

• 시스템엔지니어링학술지
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• 제14권2호
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• pp.73-82
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• 2018

In this work, a hardware based cryptographic module for the cyber security of nuclear power plant is developed using a system engineering approach. Nuclear power plants are isolated from the Internet, but as shown in the case of Iran, Man-in-the-middle attacks (MITM) could be a threat to the safety of the nuclear facilities. This FPGA-based module does not have an operating system and it provides protection as a firewall and mitigates the cyber threats. The encryption equipment consists of an encryption module, a decryption module, and interfaces for communication between modules and systems. The Advanced Encryption Standard (AES)-128, which is formally approved as top level by U.S. National Security Agency for cryptographic algorithms, is adopted. The development of the cyber security module is implemented in two main phases: reverse engineering and re-engineering. In the reverse engineering phase, the cyber security plan and system requirements are analyzed, and the AES algorithm is decomposed into functional units. In the re-engineering phase, we model the logical architecture using Vitech CORE9 software and simulate it with the Enhanced Functional Flow Block Diagram (EFFBD), which confirms the performance improvements of the hardware-based cryptographic module as compared to software based cryptography. Following this, the Hardware description language (HDL) code is developed and tested to verify the integrity of the code. Then, the developed code is implemented on the FPGA and connected to the personal computer through Recommended Standard (RS)-232 communication to perform validation of the developed component. For the future work, the developed FPGA based encryption equipment will be verified and validated in its expected operating environment by connecting it to the Advanced power reactor (APR)-1400 simulator.

• 품질경영학회지
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• 제41권4호
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• pp.725-735
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• 2013

Purpose: The purpose of this study is to propose an Integrated Safety Evaluation Process (ISEP) that can enhances the safety aspect of the safety-critical system. This process utilizes the advantages of the iterative Systems Engineering process combined with the safety assessment process that is commonly and well defined in many standards and/or guidelines for railway, aerospace, and other safety-critical systems. Methods: The proposed process model is based on the predefined system lifecycle, in each phase of which the appropriate safety assessment activities and the safety data are identified. The interfaces between Systems Engineering process and the safety assessment process are identified before the two processes are integrated. For the integration, the elements at lower level of Systems Engineering process are combined with the relevant elements of safety assessment process. This combined process model is represented as Enhanced Functional Flow Block Diagram (EFFBD) by using CORE(R) that is commercial modelling tool. Results: The proposed model is applied to the lifecycle and management process of the United States aircraft system. The US aircraft systems engineering process are composed of twelve key elements, among which the requirements management, functional analysis, and Synthesis processes are considered for examplenary application of the proposed process. To synchronize the Systems Engineering process and the safety assessment process, the Systems Engineering milestones are utilized, where the US aircraft system has thirteen milestones. Taking into account of the nine steps in the maturity level, the integrated process models are proposed in some phases of lifecycle. The flows of processes are simulated using CORE(R), confirming the flows are timelined without any conflict between the Systems Engineering process and the safety assessment process. Conclusion: ISEP allows the timeline analysis for identifying activity and data flows. Also, the use of CORE(R) is shown to be effective in the management and change of process data, which helps for the ISEP to apply for the development of safety critical system. In this study, only the first few phases of lifecyle are considered, however, the implementation through operation phases can be revised by combining the elements of safety activities regarding those phases.