• 한국CDE학회논문집
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• 제10권6호
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• pp.412-420
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• 2005

The integration of CAD and CAM is critical for computer aided process planning. Recently, STEP has been emerged and utilized as a product data exchange standard format in CAD/CAM areas. The assembly information consists of assembly component relations, assembly features, assembly directions and mating conditions. The purpose of this study is to develop an efficient algorithm to extract assembly information directly from the STEP based files and to generate automatically assembly process plan from the extracted assembly features. The developed algorithms will generate assembly information codes for STEP(AICS). The results from this study can be a reasonable link between design and manufacturing for developing better CAAPP(Computer-Aided Assembly Process Planning) systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 D
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• pp.3163-3165
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• 2000

In code division multiple access systems using all-optical signal processing, the optical multiple access interference by simultaneous multiple users degrades the system performance and eventually can limit the number of active users. To reduce the effect of the interference, error-correction codes are used in 2-dimensional FO-CDMA systems. In this paper we propose a method of applying product code to 2-dimensional FO-CDMA systems. The proposed coding scheme can correct a random error and burst errors with small redundancy to the conventional case. In result we show significant performance enhancement of the system in terms of HER, the number of active users.

• 한국통신학회논문지
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• 제34권3C호
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• pp.322-328
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• 2009

본 논문은 BER 성능을 높인 LDPC 복호를 위한 새로운 SSP 알고리즘을 제안한다. 제안하는 SSP 알고리즘은 추가적인 연산 없이 곱셈 연산과 나눗셈 연산을 덧셈 연산과 뺄셈 연산으로 대체가 가능하다. 제안하는 SSP 알고리즘은 In[tanh(x)] 함수와 $tanh^{-1}[exp(x)]$ 함수를 각각의 양자화 테이블을 사용하여 단순화하기 때문에 연산 복잡도를 줄일 수 있다. 시뮬레이션 결과 제안하는 SSP 알고리즘은 기존의 근사화 SP 알고리즘과 비교하여 BER 성능을 $0.3\;{\sim}\;0.8\;dB$ 향상시킨 것을 보여준다.

• 인터넷정보학회논문지
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• 제6권4호
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• pp.21-35
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• 2005

소프트웨어 제품 라인은 소프트웨어 자산에 존재하는 재구성 가능한 컴포넌트를 구체화하고 미리 정의된 아키텍처를 기반으로 조립함으로써 고품질의 응용 프로그램을 효율적으로 개발하기 위한 패러다임이다. 최근 컴포넌트 기반의 여러 가지 제품 라인 개발 방법론들이 제안되었지만, 가변성 지원 컴포넌트의 구체적인 구현 기술은 제공하지 못하고 있다. 한편, 가변성을 지원하기 위한 여러 가지 구현 기술이 개발되었지만, 이러한 구현 기술은 개발 초기부터 가변성을 고려한 체계적인 분석 및 설계 방법을 제공하지 못한다. 본 논문에서는, UMI 모델링 기법을 확장한 컴포넌트 기반 제품 라인 개발 방법론인 PLUS와 컴포넌트 자동 생성 기법을 결합하여 특정 제품 생산의 효율성을 높이는 기법을 제안한다. 본 논문에서의 컴포넌트는 가변성을 지원하는 구현 부품들이 계층 구조를 이루며 각 구현 부품들은 XSLT 스크립트로 작성된다. 특성 모델에서 선택된 특성들로부터 개발자가 원하는 컴포넌트의 코드가 자동 생성되며, 마이크로웨이브 오븐 제품 라인을 사례 연구로 해서 가변성 지원 컴포넌트의 개발 프로세스를 살펴본다.

• Korean Journal of Mathematics
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• 제9권2호
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• pp.129-131
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• 2001

Let $q=p^{e1}_1{\cdots}p^{em}_m$ be the product of distinct prime elements. In this short paper, we show that the largest value of M such that there exists an ($n$, M, $n-1$) $q$-ary code is $q^2$ if $n-1{\leq}p^{ei}_i$ for all $i$.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1998년도 추계학술대회 논문집
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• pp.166-170
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• 1998

Classification and Coding(C&C) systems as a core of design information management have been accomplished by many studies in terms of design and manufacturing attribute based on Group Technology. Those are very difficult to apply in make-to-order(MTO) manufacturing because the environment of MTO has various characteristics of product, many licensors, engineering change, insufficiency of integrated management system for codes and so on. This paper presents a suitable C&C system to MTO manufacturing which consider management level and drawing.

• 복식문화연구
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• 제15권1호
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• pp.1-12
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• 2007

The purpose of this study is to identify the SPA(Specialty store retailer of Private label Apparel) characteristics and product supply process of Korean casual apparel brands. The research was conducted by questionnaire surveys to 63 casual apparel brands. SPA characteristics of each brand were measured with four SPA characteristic indices: short product supply cycle, spacious retail floor, single brand retail store, and low product price compared to the quality of the product. The 63 apparel brands were grouped by SPA index score. The brands belonged to group H had high index score and brands in group L had low index score. The results of this study showed that the most of the casual apparel brands' products were sold at department stores, especially the brands belonged to group L greatly depended on department stores. Few apparel brands have spacious retail floor. The retail product price of the brands belonged to group H was low price while the product price of the brands belonged to group L was in the medium-high price. The supply time of the new products was short in general. The most brands supplied new styles to the retail floor within 1 to 3 weeks. The information technology was heavily used. The brands belonged to group H highly used information technology including bar codes system, pas data analysis, and inventory control system. The current style trends were analyzed with street fashion and feedback from the shop managers.

• 한국CDE학회논문집
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• 제1권2호
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• pp.87-96
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• 1996

IGES is a file format which has gained widespread use but has certain limitations such as limited information coverage and ambiguous definitions. In order to overcome the limitations of existing neutral file formats, STEP has been developed as a more comprehensive mechanism for product data exchange by ISO. This paper describes a file translation system between IGES and STEP. In this system, three EXPRESS schemata are defined for IGES, STEP and the translation relationship between IGES and STEP. Object codes are generated from the schemata and linked with file access libraries to IGES and STEP files. The translation was verified by visualization and reverse translation. The system developed in this study can easily applied to translate other file formats because the file structure and translation relationship are defined in EXPRESS - a high level information modeling language.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.643-652
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• 2009

This paper presents brief history and a state-of-the-art survey of Life Cycle Cost (LCC) analysis, in particular LCC analysis in the Urban Transit Vehicle, based on a internationl codes and standards related to LCC analysis. A main objective of the LCC analysis is to quantify the total cost of ownership of a product throughout its full life cycle, which includes research and development, construction, operation and maintenance, and disposal. The predicted LCC is useful information for decision making in purchasing a product, in optimizing design, in scheduling maintenance, or in planning overhaul. This paper presents a LCC procedure consisting of seven steps, which are "Problems definition", "Cost elements definition", "System modeling", "Data collection", "Cost profile development", "Evaluation", and "Verification". Sub-activities to be encompassed in the seven steps procedure are described.

• 동력기계공학회지
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• 제18권6호
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• pp.91-98
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• 2014

The purpose of this research is to investigate optimum machining conditions to improve the quality of die using the CAD/CAM system(Power Shape/Power Mill) and 3D printing. Surface roughness is widely used as an index for processing degree of accuracy. The Power Shape was used to model the shape of product. And the model shape is confirmed by 3D printing system(BFB-3000). Also, tool path and NC-codes were generated using Power Mill. Finally, the product was cut using CNC machine(NBS-2025). The cutting time and surface roughness were measured by measuring instrument. And then this process was repeated by changing the conditions to find optimal machining conditions. The surface roughness behavior with regard to specific factors were analyzed. Through this study, the optimal machining condition can be obtained.