• 산업기술연구
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• 제43권1호
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• pp.49-55
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• 2023

Cluster tools are extensively employed in various wafer fabrication processes within the semiconductor manufacturing industry, including photo lithography, etching, and chemical vapor deposition. Contemporary fabrication facilities encounter customer orders with technical specifications that are similar yet slightly varied. Consequently, modern fabrications concurrently manufacture two or three different wafer types using a cluster tool to maximize chamber utilization and streamline the flow of wafer lots between different process stages. In this review, we introduce two methods of concurrent processing of multiple wafer types: 1) concurrent processing of multiple wafer types with different job flows, 2) concurrent processing of multiple wafer types with identical job flows. We describe relevant research trends and achievements and discuss future research directions.

• 품질경영학회지
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• 제29권3호
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• pp.138-150
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• 2001

Recently, industrial environments have been drastically changed. Customers require cheaper, better, stronger products more than ever. Thus companies have to satisfy the requirements of customers to be survived in this kind of industrial environments. To cope with these requirements from customers, engineers in industries must accept new paradigm and use some special tools for developing new product. This study has applied a Concurrent Engineering which would be good for shortening of product development period in developing of Full Logic Deck mechanism using in car audio. In this paper, a real case of systematic approach and successful story of Concurrent Engineering application in developing Full Logic Deck mechanism is illustrated.

• 산업공학
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• 제7권3호
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• pp.101-111
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• 1994

• Structural Engineering and Mechanics
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• 제81권3호
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• pp.267-280
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• 2022

Multiscale structure has attracted significant interest due to its high stiffness/strength to weight ratios and multifunctional performance. However, most of the existing concurrent topology optimization works are carried out under deterministic load conditions. Hence, this paper proposes a robust concurrent topology optimization method based on the bidirectional evolutionary structural optimization (BESO) method for the design of structures composed of periodic microstructures subjected to uncertain dynamic loads. The robust objective function is defined as the weighted sum of the mean and standard deviation of the module of dynamic structural compliance with constraints are imposed to both macro- and microscale structure volume fractions. The polynomial chaos expansion (PCE) method is used to quantify and propagate load uncertainty to evaluate the objective function. The effective properties of microstructure is evaluated by the numerical homogenization method. To release the computation burden, the decoupled sensitivity analysis method is proposed for microscale design variables. The proposed method is a non-intrusive method, and it can be conveniently extended to many topology optimization problems with other distributions. Several numerical examples are used to validate the effectiveness of the proposed robust concurrent topology optimization method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권3호
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• pp.965-983
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• 2014

Concurrent behaviors of multithreaded programs cannot be described effectively by automata-based models. Thus, concurrent program intrusion attempts cannot be detected. To address this problem, we proposed the process algebra-based detection model for multithreaded programs (PADMP). We generate process expressions by static binary code analysis. We then add concurrency operators to process expressions and propose a model construction algorithm based on process algebra. We also present a definition of process equivalence and behavior detection rules. Experiments demonstrate that the proposed method can accurately detect errors in multithreaded programs and has linear space-time complexity. The proposed method provides effective support for concurrent behavior modeling and detection.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 1999년도 춘계학술대회 발표논문집
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• pp.135-144
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• 1999

A major concern in Concurrent Engineering is the control and management of workload in a period of process. As a general rule, leveling the peak of workload in a certain period is difficult because concurrent processing is comprised of various processes, including overlapping, paralleling and looping. Therefore, workload management with resource constraints is so beneficial that effective methods to analyze design process This study presents a procedure to transform the IDEF3 process model into the precedence logic network model for more useful assessment of the process. This approach is expected to facilitate resolving resource constrained scheduling problems more systematically in Concurrent Engineering environment.

• Structural Engineering and Mechanics
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• 제76권4호
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• pp.529-540
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• 2020

Concurrent topology optimization of macrostructure and microstructure has attracted significant interest due to its high structural performance. However, most of the existing works are carried out under deterministic conditions, the obtained design may be vulnerable or even cause catastrophic failure when the load position exists uncertainty. Therefore, it is necessary to take load position uncertainty into consideration in structural design. This paper presents a computational method for robust concurrent topology optimization with consideration of load position uncertainty. The weighted sum of the mean and standard deviation of the structural compliance is defined as the objective function with constraints are imposed to both macro- and micro-scale structure volume fractions. The Bivariate Dimension Reduction method and Gauss-type quadrature (BDRGQ) are used to quantify and propagate load uncertainty to calculate the objective function. The effective properties of microstructure are evaluated by the numerical homogenization method. To release the computation burden, the decoupled sensitivity analysis method is proposed for microscale design variables. The bi-directional evolutionary structural optimization (BESO) method is used to obtain the black-and-white designs. Several 2D and 3D examples are presented to validate the effectiveness of the proposed robust concurrent topology optimization method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.145-146
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• 2006

In this paper, when concurrent transmission and diversity reception at each relay are assumed to increase bandwidth efficiency in linear multihop system, we analyze interference due to concurrent transmission and verify it. In the interference-free environment, more diversity sources at each relay result in better performance [1][2]. However, interference degrades BER performance because accumulated and propagated interference power surpasses original data power. Therefore, if we use the result of this paper, we can make bandwidth efficiency increase as well as BER performance good in linear multihop system by considering concurrent transmission with reuse factor and developing the algorithm which determines the number of diversity source.

• 한국정보처리학회논문지
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• 제6권7호
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• pp.1941-1954
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• 1999

본 논문은 ITU-T 통신 처리 시스템용 프로그래밍 언어 CHILL에서 제공되는 병행처리 기능을 적용하기 위한 CHILL 실행시간 지원 시스템(CRS : CHILL Run-time support System)의 설계 및 구현에 관한 연구이다. CHILL은 다른 병행 프로그래밍 언어에 비해 다양한 병행처리 기능들을 제공하고 있기 때문에, CRS의 설계는 병행처리 기능의 인터페이스 규격을 설계한다. CHILL의 병행처리 프리미티브는 프로시듀어 호출 형식으로 사용하도록 라이브러리 방식을 사용하며, CHILL 프로세스의 실행을 병행적으로 제어하기 위해 CHILL 프로그램 구동 루팀 및 문맥 교환부와 CHILL 프로세스 제어부를 구현한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.438-441
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• 2003

건설 산업 대부분의 프로젝트에서 공기지연의 발생은 매우 일반적이나 CPM, Bar Chart와 같은 지연분석 기법들로서는 분석하기 매우 어렵다. CPM과 Bar chart를 이용하는 분석기법들은 동시발생과 생산성 손실 지연을 분석하기에 불충분하기 때문이다. 생산성 손실 지연은 동시발생 지연 분석 및 지연 일수 산정에서 중단으로 인한 지연과 다르게 분석되어야 한다. 본 논문에서는 동시발생 공기지연 분석을 포함하여 생산성을 고려한 공기지연 분석방법에 대하여 논하였다.