• 한국국방경영분석학회지
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• 제18권2호
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• pp.23-43
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• 1992

A Stochastic simulation model for optimal design and evaluation of the integrated weapon systems under the consideration of the RAM (reliability, availability and maintainability) and life cycle cost (LCC) was developped. This model is supposed to satisfy a need regarding the methodology of optimaldesign and performance evaluation for both developpers and users of weapon systems.

• 한국자동차공학회논문집
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• 제24권4호
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• pp.439-446
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• 2016

An in-wheel motor vehicle is a type of car that is equipped with an electric motor for each wheel. It is possible to acquire vehicle stability through a seperate driving torque control per wheel, since it directly generates the driving torque via the wheel motors. However, the vehicle ride comfort and road holding performance worsen depending on the increase of the wheel weights. In order to compensate for the impaired performance, an integrated chassis control system of the rear in-wheel motor vehicle is proposed. The proposed integrated chassis control system is composed of a driving torque control system, a semi-active suspension system, and an ESC system. According to the vehicle dynamic simulation of an in-wheel motor vehicle equipped with the integrated chassis control system, it is found that the system can improve the driving stability, ride comfort, and driving efficiency of the in-wheel motor vehicle.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1992년도 수공학연구발표회논문집
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• pp.443-447
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• 1992

This study describes the strategy for advanced decision support system (ADSS) development for integrated management of water resources and quality in reservoir systems. The developed ADSS consists of database that contain hydrologic data, observed operational data, and data to support specific reservoir operations simulation, optimization models, and water quality models. The optimization model, mass balance simulation model and water quality models are used in a general prototype ADSS, menu driven controlling framework that assists the user to specify and evaluate the alternative operational scenarios at one time. These alternative scenarios are evaluated by the models and the results are compared through the use of a graphical based display system. This graphical based system uses an icon based schematic representation of the system to organize the presentation of the results. The ADSS includes the ability to use monthly or weekly time periods of analysis for the models and it can use monthly historical or stochastically generated inflows.

• 한국시스템다이내믹스연구
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• 제12권3호
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• pp.67-86
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• 2011

This study shows the reduction effect of freight volume by the supply chain redesign for the alliance of distributors with system dynamics simulation. The as-is model is composed of 3 independent companies which one has 3 distribution centers (DCS) and 24 agents, another has 1 dc and 9 agents, the other has 3 DCS and 15 agents each. The to-be model is an integrated logistics model and composed of 1 company having 5 areal DCS and 38 agents. Each agent in the same area is integrated with each other. Two models have same demands but very different result. As a result, the freight volume between DCS and agents is reduced by 33.55%. This case study will be useful to analyze the similar cases about the logistics integration by supply chain redesign.

• 한국시뮬레이션학회논문지
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• 제20권3호
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• pp.19-28
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• 2011

적응적 랜덤 테스팅(ART)은 순수 랜덤 테스팅의 효율성을 개선하기 위해 제안된 방법으로 효과적인 테스트 케이스의 선택을 통해 보다 적은 수의 테스트 케이스로 소프트웨어 내에 존재하는 오류 영역을 찾는 것을 목적으로 한다. 기존의 ART는 하나의 시스템 혹은 유닛에 대한 테스트를 적용 대상으로 하고 있으며, 다양한 접근 방법을 이용해 순수 랜덤 테스팅보다 우수한 성능을 보여 왔다. 하지만 통합 시스템을 구성하는 특정 유닛에 대해 ART를 적용하고자 하는 경우에는 시스템을 구성하는 타 유닛들의 영향으로 인해 기대 이하의 효율성을 보이게 된다. 따라서 본 논문에서는 이와 같은 테스트 환경 대한 ART 적용방법의 하나로, 테스트 대상 유닛에 부여되는 입력 데이터의 분포를 통합 시스템에 대한 제한된 수의 입력을 사용하여 예측하고, 이를 바탕으로 시스템의 입력 도메인 분할 크기를 조절하는 방법을 제안하고 시뮬레이션을 통해 성능을 평가한다. 시뮬레이션 결과, 제안된 방법은 유닛 테스팅에 ART를 적용했을 때와 유사한 수준의 성능으로 통합 시스템 내의 특정 유닛을 테스트 가능하도록 하며, 오류 비율의 변화가 ART의 성능에 미치는 영향 또한 1% 이내 수준으로 안정임을 확인하였다.

• Architectural research
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• 제14권4호
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• pp.117-124
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• 2012

High rise office buildings represent one of the most energy-intensive architectural typologies. The growth of urban population necessitates sustainable high rise towers that lessen environmental impacts and energy consumption. Among various sustainable strategies, the integrated design is long known to be an important process that has great impact on building's sustainability. The framework for this paper is based on the case study of integrated towers that are located in different climate zones. The paper specifically addresses to what extent climate conditions influence the design of a high rise building and what kinds of the climate integrated design has been implemented. Qualitative case studies were carried out using published data and architectural drawing set. The technical work presented in the paper is based on computer simulation that examines the insolation analysis using hourly recorded weather data. The analysis results revealed that the site and building envelope integration and the site and building service systems have shown the most frequently employed in the integrated towers through the implementation of renewable resource integration, high performance envelopes and sustainable building service systems. Internal comfort and further energy saving in the integrated towers are offered through an automatic building management system. Due to the dynamic climate conditions, integration of building systems requires a sophisticated approach to building sustainability.

• 한국전자파학회논문지
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• 제20권9호
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• pp.890-899
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• 2009

차세대 이동 위성 시스템의 주요 서비스중 하나는 멀티미디어 방송 및 멀티캐스팅 서비스가 될 것이다. 이러한 서비스를 효과적으로 제공하기 위해 통합 위성 지장 네트워크가 고려될 수 있다. 본 논문에서는 차세대 이동위성 시스템에 적합한 통합 위성 지상 시스템의 구조를 소개하고, 효율적인 이동 위성 멀티미디어 방송 및 멀티캐스팅 서비스를 제공하기 위한 위성과 지상 보조 장치 간의 협력적 전송 기법들을 제안하였다. 성능 분석 시뮬레이션 결과, 제안한 구조가 시스템 성능을 보다 향상시킬 수 있으며 효과적인 전송을 할 수 있음을 보여준다.

• 한국공간구조학회논문집
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• 제19권2호
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• pp.43-50
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• 2019

A smart connective control system was invented recently for coupling control of adjacent buildings. Previous studies on this topic focused on development of control algorithm for the smart connective control system and design method of control device. Usually, a smart control devices are applied to building structures after structural design. However, because structural characteristics of building structure with control devices changes, a iterative design is required for optimal design. To defeat this problem, an integrated optimal design method for a smart connective control system and connected buildings was proposed. For this purpose, an artificial seismic load was generated for control performance evaluation of the smart coupling control system. 20-story and 12-story adjacent buildings were used as example structures and an MR (magnetorheological) damper was used as a smart control device to connect adjacent two buildings. NSGA-II was used for multi-objective integrated optimization of structure-smart control device. Numerical simulation results show the integrated optimal design method proposed in this study can provide various optimal designs for smart connective control system and connected buildings presenting good control performance.

• 대한교통학회지
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• 제26권6호
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• pp.93-101
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• 2008

무선 통신 장비의 빠른 확산과 함께 교통 분야에도 새로운 시도가 이루어지고 있다. 무선 통신 기술의 하나인 애드혹 네트워크를 차량에 적용한 Vehicular Ad hoc Networks (VANETs)은 주행중인 차량간의 통신을 가능하게 하여 교통 안전, 혼잡 정보 등의 교통 정보 전달에 활용이 검토되고 있다. 하지만, VANET 기술은 아직 연구 수준이고, 실험에 있어 시간과 비용의 한계 때문에 컴퓨터 모의실험에 의존하고 있다. VANET 기반은 교통과 통신의 통합된 환경임에도 불구하고, 이전 연구에서는 한 분야만의 환경을 고려하였거나, 현실적인 통합 환경을 이루지 못하였다. 본 연구에서는 기존 실험의 한계를 극복하기 위하여, 실제 VANET 기반 교통 시스템에서 발생하는 차량의 움직임과 무선 통신 특성을 표현하기 위한 미시적 교통 모의실험 모형과 통신 모의실험 모형을 시 공간적으로 동기화한 모의실험 환경을 설계하였다. 사례 연구로, 실제 도로 및 교통 수요 자료를 사용하여 설계된 모의실험 환경을 적용하였고, 교통 특성과 통신 특성을 잘 반영하는 결과를 얻었다. 향후, 본 연구에서 설계된 모의실험 환경은 VANET 기반 교통 시스템의 다양한 설계에 활용될 것으로 기대된다.

• Nuclear Engineering and Technology
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• 제49권2호
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• pp.295-305
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• 2017

This paper reviews current status of the unified approach known as integrated safety assessment (ISA), as well as the associated SCAIS (simulation codes system for ISA) computer platform. These constitute a proposal, which is the result of collaborative action among the Nuclear Safety Council (CSN), University of Madrid (UPM), and NFQ Solutions S.L, aiming to allow independent regulatory verification of industry quantitative risk assessments. The content elaborates on discussions of the classical treatment of time in conventional probabilistic safety assessment (PSA) sequences and states important conclusions that can be used to avoid systematic and unacceptable underestimation of the failure exceedance frequencies. The unified ISA method meets this challenge by coupling deterministic and probabilistic mutual influences. The feasibility of the approach is illustrated with some examples of its application to a real size plant.