• 조명전기설비학회논문지
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• 제24권5호
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• pp.55-61
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• 2010

PLC 제어 시스템은 SFC 언어를 사용하여 설계할 경우, SFC 언어를 사용하면 제어의 흐름을 이해하기 쉽고, 유지보수가 용이하며 프로그램의 기술성이 뛰어나다. SFC 언어는 단일 시퀀스, 선택 시퀀스, 병렬 시퀀스로 나누어지며, 선택 시퀀스로 프로그래밍 하면 단일 시퀀스로 프로그램할 때보다 메모리의 크기가 커져야 한다. 본 논문에서는 선택 시퀀스의 기능을 단일 시퀀스로 구현하여 메모리의 크기를 줄여서 메모리의 효율을 향상시키는 방법을 제시하고, 실례를 통해 타당성을 확인하였다.

• 한국자동차공학회논문집
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• 제15권6호
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• pp.170-176
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• 2007

It is time to prepare the phaseout of R134a, the current refrigerant, in automotive air conditioning system because the EC deadline has been coming with new platform vehicles in 2011 and all vehicles by 2017. Until now a high-pressure carbon dioxide($CO_2$) system is the leading replacement of R134a in European auto-makers but there is no firm agreement in the world automotive market. Recently three new fluids have been announced as the possibilities from Honeywell, DuPont and INEOS Fluor. The new alternative refrigerant should meet the requirements like non flammable, non toxic, no ozone depletion effect and low GWP(under 150 to meet EC regulation). The objectives of this paper are to review the fluid H from Honeywell, the more possible alternative refrigerant in 3 new fluids, compare the properties of R134a & fluid H and see the possibility as a replacement of R134a. In this experimental paper we ran and reviewed the cooling performance data in the bench system, the vehicle and the field test. We found the possibility of fluid H system to meet the R134a system performance with some hardware modifications but agreed that it is still needed to study about the long term safety, environmental effects, material compatibilities and so on.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1999년도 추계학술대회 논문집
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• pp.63-69
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• 1999

The research trend of the simulation optimization has been focused on exploring continuous decision variables. Yet, the research in discrete decision variable area has not been fully studied. A new research trend for optimizing discrete decision variables ha just appeared recently. This study, therefore, deals with a discrete simulation method to get the system evaluation criteria required for designing a complex probabilistic discrete event system and to search the effective and reliable alternatives to satisfy the objective values of the given system through a on-line, single run with the short time period. Finding the alternative, we construct an algorithm which changes values of decision variables and a design alternative by using the stopping algorithm which ends the simulation in a steady state of system. To avoid the loss of data while analyzing the acquired design alternative in the steady state, we provide background for estimation of an auto-regressive model and mean and confidence interval for evaluating correctly the objective function obtained by small amount of output data through simulation with the short time period. In numerical experiment we applied the proposed algorithm to (s, S) inventory system problem with varying Δt value. In case of the (s, S) inventory system, we obtained good design alternative when Δt value is larger than 100.

• 수산해양교육연구
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• 제25권2호
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• pp.301-306
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• 2013

In this paper, cycle performance analysis of two-stage compression and two-stage expansion refrigeration system using alternative freon refrigerants is presented to offer the basic design data for the operating parameters of the system. Alternative freon refrigerant for freon refrigerant R22 were used as working fluids in this study. The operating parameters considered in this study included evaporation temperature, condensation temperature, subcooling degree, superheating degree, and mass flow rate ratio of inter-cooler. The main results were summarized as follows : The COP of two-stage compression and two-stage expansion refrigeration system increases with the increasing subcooling degree and mass flow rate ratio of inter-cooler, but decreases with the increasing evaporating temperature, condensing temperature and superheating degree. Therefore, subcooling degree, mass flow rate ratio of inter-cooler of two-stage compression and two-stage expansion refrigeration system using alternative freon refrigerants have an effect on COP of this system.

• 정보처리학회논문지B
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• 제12B권3호
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• pp.323-328
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• 2005

본 연구는 보완 대체 통신을 위한 문장생성에 관한 것이다. 문장생성의 목적은 언어생활이 불편한 사람들을 위한 보완 대체 통신에 사용하기 위해서이다. 보완 대체 통신은 사용자가 원하는 문장을 만들어 음성으로 출력해주는 시스템이다. 문장을 생성하기 위해서 어휘 정보를 보완대체 통신의 개념에 맞도록 변형하여 도입하였고, 어휘정보는 동사에 연결될 수 있는 명사와 조사로 이루어져 있다. 어휘정보를 이용하여 시스템을 구현하였고, 구현된 시스템으로 문장생성의 효용을 측정하였다. 구축된 시스템은 올바른 문장의 생성과 저장, 검색, 어휘입력의 기능을 갖는다.

• 한국건축시공학회지
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• 제8권1호
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• pp.97-102
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• 2008

The report of the Korean Board of Audit and Inspection(BAI) on May 2007 indicates the problems of Life Cycle Cost (LCC) analysis and evaluation in the Design-Build(Turn-Key) and alternative bidding system. The point which the report indicates is that the cost estimation system for LCC analysis has nothing in common each other and there's no consistency among the repair cycle and ratio per facilities parts. For solving these problems, BAI demands the establishment of the guidelines for LCC analysis and evaluation from the competent authority Korean Ministry of Construction And Transportation(MOCT). The objective of this study is to develop the improvement directions for LCC analysis and evaluation which are suitable to the public construction projects especially for the Design-Build and alternative bidding system in Korea. For this study, the LCC related raws and regulations, LCC analysis guidelines of public cooperations, actual condition of LCC analysis and evaluation which include, the elements of LCC, the estimation rules of the initial cost and the maintenance cost, the analysis standards of time value of money, etc. are investigated to provide the improvement directions for LCC analysis and evaluation.

• 한국시뮬레이션학회논문지
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• 제25권4호
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• pp.1-12
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• 2016

항공기 엔진부품을 생산하는 제조산업은 전통적인 주문형 제조방식을 따르며, 다품종 소량생산시스템이다. 또한 생산공장의 배치는 유사한 기능을 가지는 병렬 기계들이 공정별 배치 형태로 구성되어 있고 조립공정이 포함되는 Hybrid Job Shop이다. 더 나아가 다양한 대체장비를 가지고 있으며, 공정 경로도 다양하고, 조립공정도 포함되어 있다. 이와 같은 복잡한 시스템의 생산능력을 검증하기 위해서는 시뮬레이션이 가장 우수한 방법이며, 정확한 모델의 개발을 위해 고도의 시뮬레이션 모델링기술이 필요하다. 이 논문에서는 위에서 언급한 복잡한 특성을 가진 생산시스템을 효과적으로 모델링하기 위한 방법론을 소개하고, 실제 항공기부품 생산업체를 대상으로 시뮬레이션 연구를 수행한 사례에 대해 소개한다.

• 한국중재학회지:중재연구
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• 제19권3호
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• pp.199-217
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• 2009

During the urbanization progresses, apartments such as the house of commons, representing our homes are situated in space. However, many consumer problems of our country's apartment house are caused by the government's failure of housing policy and consumer dispute resolution system In this study, apartment house and alleviate consumer disputes relating to in proactive ways to improve the government's housing policy was presented. At the same time, since the revision of Consumer Fundamental Act on collective alternative dispute resolution system has proposed scheme, this occurred after a dispute to resolve the dispute can be more efficient ways.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1998년도 The Korea Society for Simulation 98 춘계학술대회 논문집
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• pp.50-55
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• 1998

In this paper we use discrete simulation method to get the criteria of system evaluation required in the case of designing the complicated probabilistic event system having discrete probabilistic variables and to search the effective and reliable alternatives to satisfy the objective value of the given system through on-line, single run within the short time period. If we find the alternative we construct the algorithm which change values of decision variables and determining alternative by using the stopping algorithm which end the simulation in the steady state of system. In order to prevent the loss of data when we analyze the acquired design alternative in the steady state we provide the background of the estimation of the autoregressive model and mean and confidence interval for evaluating correctly the objective function obtained by the small amount of output data through the short time period simulation.

• Steel and Composite Structures
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• 제20권5호
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• pp.1133-1153
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• 2016

In this article, an additive performance ratio method using structural analysis of both 2D and 3D is introduced to mitigate the complexity of work evaluating structural performances of numerous steel outrigger alternatives in multi-story buildings, especially high-rise buildings. The combined structural analysis process enables to be the design of economic, safe, and as constructional demanding structures by exploiting the advantages of steel, namely: excellent energy dissipation and ductility. First the approach decides the alternative of numerous steel outriggers by a simple 2D analysis module and then the alternative is evaluated by 3D analysis module. Initial structural analyses of outrigger types are carried out through MIDAS Gen 2D modeling, approximately, and then the results appeal structural performance and lead to decide some alternative of outrigger types. ETABS 3D modeling is used with respect to realization and evaluation of exact structural behaviors. The approach reduces computational burden in compared to existing concepts such as full 3D analysis methods. The combined 2D and 3D tools are verified by cycle and displacement tests including comprehensive nonlinear dynamic simulations. The advantages and limitations of the Additive Performance Ratio Approach are highlighted in a case study on a high rise steel-composite building, which targets at designing the optimized alternative to the existing original outrigger for lateral load resisting system.