• 품질경영학회지
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• 제30권4호
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• pp.58-67
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• 2002

Since the inception of off-line quality control, it has drawn a particular attention from research community and it has been implemented in a wide variety of industries mainly due to its extensive applicability to numerous real situations. Emphasizing design issues rather than control issues related to manufacturing processes, off-line quality control has been recognized as a cost-effective approach to quality improvement. It mainly consists of three design stages: system design, parameter design, and tolerance design which are implemented in a sequential manner. Utilizing experimental designs and optimization techniques, off-line quality control is aimed at achieving product performance insensitive to external noises by reducing process variability. In spite of its conceptual soundness and practical significance, however, off-line quality control has also been criticized to a great extent due to its heuristic nature of investigation. In addition, it has also been pointed out that the process optimization procedures are inefficient. To enhance the current practice of off-line quality control, this study proposes an integrated optimization model by utilizing a well-established statistical tool, so called response surface methodology (RSM), and a tolerance - cost relationship.

• 한국정보기술학회논문지
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• 제16권12호
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• pp.115-125
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• 2018

2015 개정 교육과정의 핵심은 성취평가제의 적용과 확산으로서 학생들의 학업 성취 평가에서 있어서 경쟁적인 상대평가에서 벗어나 학생들이 각각의 평가기준에 따라 어느 정도의 학업 성취를 달성하였는가를 평가하는 것이다. 이를 위해서는 교수학습 설계와 수행 및 평가 프로세스를 통합 관리할 수 있는 평가기준 및 성취수준 지원 시스템이 필요하다. 본 논문에서는 교육과정의 성취기준 자료, 수업설계 자료, 학습내용 자료, 평가설계 자료, 평가결과분석 자료 및 피드백 자료들을 연계할 수 있는 통합 데이터모델을 설계하고 이에 기반한 성취평가 지원 시스템을 설계한다. 설계한 통합 데이터 모델을 기반으로 학습자 대쉬보드 웹페이지 프로토타입을 구현하고 학생평가지원포털과의 검색 기능을 비교함으로써 제안한 모델의 퀄리티를 평가하였다.

• 한국습지학회지
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• 제13권3호
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• pp.593-602
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• 2011

지난 반세기 동안의 무분별한 개발로 인하여 하구역 생태 환경은 심각하게 훼손되었다. 이를 관리하기 위한 전 지구적 요구는 증대되고 있으나 효율적으로 관리할 수 있는 시스템은 부재한 실정이다. 따라서 본 연구에서는 기관별로 산재된 하구역 생태 환경 데이터를 통합하여 하구역을 효과적으로 관리할 수 있는 통합 DB관리시스템을 개발고자 하였다. 이를 위해 2010년 영산강 하구역을 대상으로 실시한 모니터링 DB와 공간 데이터 표출에 우수한 GIS DB를 통합하여 시스템 개발에 적용하였다. 시스템의 개발환경은 VisualBasic.NET과 지도기반의 공간 분석을 위한 ArcObjects 컴포넌트를 이용하였다. 또한 데이터의 활용을 높이기 위하여 사용자 요구분석을 통한 GUI(Graphical User Interface)의 구성, 모니터링 DB의 표출방안, 레이어의 우선순위, 모듈단위 기능 등을 정의하였고, 최종적으로 정의된 내용을 바탕으로 시스템을 개발하였다. 본 연구에서 개발된 통합 DB관리시스템은 영산강의 현 생태 환경을 파악할 수 있으며, 사용자에게 효율적인 공유 및 관리환경을 지원할 것으로 예측된다. 향후에는 모델링 시스템과 연계하여 미래 하구역 생태 환경의 종합적인 진단 및 신뢰성 있는 예측이 가능할 것으로 기대된다.

• Nuclear Engineering and Technology
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• 제54권8호
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• pp.2828-2839
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• 2022

This study developed a safety assessment tool for geological disposal systems called APro, a systemically integrated modeling system based on modularizing and coupling the processes which need to be considered in a geological disposal system. Thermal, hydraulic, chemical, canister failure, radionuclide release and transport processes were considered in the current version of APro. Each of the unit processes in APro consists of a single Default Module, and several Alternative Modules which can increase the flexibility of the model. As an initial stage of developing the modularization concept and modeling interface, the Default Modules of each unit process were described, with one Alternative Module of chemical process. The computation part of APro is mainly a MATLAB workspace controlling COMSOL and PHREEQC, which are coupled by an operator splitting scheme. The APro model domain is a stylized geological disposal system employing the Swedish disposal concept (KBS-3 type), but the repository layout can be freely adjusted. In order to show the applicability of APro to the total system performance assessment of geological disposal system, some sample simulations were conducted. From the results, it was confirmed that coupling of the thermal and hydraulic processes and coupling of the canister failure and the radionuclide release processes were well reflected in APro. In addition, the technical connectivity between COMSOL and PHREEQC was also confirmed.

• Management Science and Financial Engineering
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• 제11권1호
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• pp.1-24
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• 2005

The results of a study of the coordination effect in stocking and promotional markdown policies for a supply chain consisting of a retailer and a discount outlet (DCO) are reported here. We assume that the product is sold in two consecutive periods: the Normal Sales Period (NSP) and the subsequent Promotional Markdown Sales Period (PSP). We first study an integrated supply chain in which managers in the two periods design a common system so as to jointly decide the stocking quantities, markdown time schedule, and markdown price to maximize mutual profit. Next, we consider a decentralized supply chain. An uncoordinated contract is designed in which decisions are decentralized to optimize the individual party's objective function. Here, three sources of system inefficiencies cause the decentralized system to earn a lower expected system profit than that in the integrated supply chain. The three sources are as follows: in the decentralized system the retailer tends to (1) stock less, and (2) keep a longer sales period, and the DCO tends to (3) stock fewer leftovers inventories and charge a higher markdown price. Finally, a numerical experiment is provided to compare the coordinated model with the uncoordinated model to explore factors that make coordination an effective approach.

• Industrial Engineering and Management Systems
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• 제15권4호
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• pp.403-431
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• 2016

The objective of this study is to integrate the business, maintenance and production processes of a manufacturing system by incorporating errors. First, the required functions are estimated according to the historical data. The system activities are simulated by Visual SLAM software and the required outputs are obtained. Several outputs including lead times in different dimensions, total cost and production rates are computed through simulation. Finally, data envelopment analysis (DEA) is utilized in order to select the best option between the defined scenarios due to the multi-criteria feature of the problem. This is the first study in which the lead times, cost and production rates are simultaneously considered in the integrated system imposed of business, maintenance and production processes by incorporating errors. In the current study, the major bottlenecks of the system being studied are identified and suggested different strategies to improve the system and make the best decision.

• 한국자동차공학회논문집
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• 제20권6호
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• pp.117-125
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• 2012

This paper describes a model-based software development methodology for AUTOSAR-ready light software architecture(AUTOSAR-Lite). The proposed methodology briefly represents an application software modeling technique using Matlab/Simulink. Using the proposed technique, application software architecture elements (e.g. software components, runnables, and interfaces) and functional behaviors can be designed in a single modeling environment. From the designed model, the codes of application software is automatically generated using Real-Time Workshop Embedded Coder. The generated application software is easily integrated with hand-coded basic software using the proposed method. In order to evaluate the proposed methodology, a diesel engine management system for a passenger car was employed as a case study. Based on the methodology, 8 atomic software components and 52 runnables are successfully developed, and they are evaluated by engine experiments. From this case study, AUTOSAR compatible model-based application software was successfully developed, and the effectiveness of the proposed methodology was evaluated.

• 한국CDE학회논문집
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• 제13권1호
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• pp.36-44
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• 2008

This paper proposes a modeling and simulation process of a panel production line (PPL) in a shipyard. The panel production line is an assembly process to produce a main panel of a flat block and a curved block. In this paper, its activity analysis is carried out using expression of IDEF0, and its process is qualitatively and quantitatively analyzed and modeled by Petri Nets. A commercial discrete event simulation tool, $QUEST^{TM}$, is used for virtual PPL and simulation. The modeling results by Petri Net are mapped to elements of the simulation tool. Finally, an integrated simulation environment of PPL is implemented in order to efficiently utilize the virtual PPL model. With the help of IDEF0 and Petri Nets, we could systematically analyze and describe the PPL process that are characterized as being concurrent, asynchronous, distributed, parallel, nondeterministic, and/or stochastic. Also, the dynamic and concurrent activities of a PPL system were able to be simulated. A timing concept can be included into the Petri nets model to evaluate performance and dependability issues of the system.

• 한국정보과학회논문지:소프트웨어및응용
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• 제28권1호
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• pp.14-25
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• 2001

XML은 다양하게 응용할 수가 있어 여러 분야에서 널리 사용되고 있다. 그러나 이러한 응용들에 대해서 통합적으로 관리해 주는 시스템은 제안된 바 없어, 각각의 응용에 대해 별개의 언어로 사용되고 있다. 따라서, 본 논문은 XML의 다양한 응용 중에 웹을 기반으로 하는 대표적인 응용인 SMIL, RDF, WIDL에 대해, 이들의 DTD와 문서 인스턴스를 통합하여 객체 모델링을 하고자 한다. 각 XML 응용에 대해 객체 모델링 규칙과 알고리즘을 통합할 수 있는 시스템을 제안한다. 이를 통해 XML 종류에 상관없이 웹 기반 XML 응용의 구조를 쉽게 파악할 수 있으므로 문서 생성을 용이하게 하며, 객체지향 스키마를 쉽게 생성할 수 있으므로 객체지향 데이터베이스 문서관리의 기반이 될 것이다.

• 대한안전경영과학회지
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• 제11권2호
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• pp.137-144
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• 2009

EPCIS(EPC Information Services) system is a core component of EPCglobal Architecture Framework offering information of the freights, the time of awareness and the location of awareness on the EPCglobal Network. The role of EPCIS is to exchange information based on EPC. There are four kinds of event data which are object event data, aggregation event data, quantity event data, and transaction event data. These EPCIS events data are stored and managed in EPCIS repository. This study suggest the quantitative modeling about total number of EPCIS event data under the assumption to aware the RFID tags of items, cases(boxes), vehicles(carriers, forklifts, auto guided vehicles, rolltainers) at a time on the reading points. We also estimate the number of created EPCIS event data by the suggested quantitative modeling under scenario of process in the integrated logistics center based on RFID system And this study compare the TO-BE model with the AS-IS model about the total sizes of created EPCIS event data using the simulation, in which we suggested the TO-BE model as the development of the repository by skipping the overlapped records.