• 한국지능시스템학회논문지
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• 제10권3호
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• pp.242-251
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• 2000

퍼지관계 개념을 응용한 BK-퍼지정보검색기법은 형태론에 입각하는 기존의 정보검색기법과는 달리 문서와 용어의 상대적 의미에 근거한 정보검색 기법이다. 그러나 BK-퍼지정보검색기법은 높은 시간복잡도(time complexity)의 검색 연산을 내재하고 있어 실제 대용량의 정보 검색은 사실상 불가능하다. 본 논문에서는 BK-퍼지검색정보모델의 시간복잡도를 낮추기 위해, 축소용어집합(reduced term set)을 이용한 개선된 BK-퍼지정보검색모델(A-FIRM)을 제안한다. 개선된 BK-FIRM은 시스템 처리시간과 신뢰도 간 상층점(trade-off)을 제공한다. 축소용어집합은 용어집합의 부분집합으로서 검색결과의 신뢰도와 밀접한 관계를 가진다. 동일한 크기의 축소용어집합이 주어질 때, 보다 적절한 용어들로 구성된 축소용어집합이 보다 나은 검색 신뢰도를 이끈다. 따라서 보다 적절한 축소용어집합 구성을 위한 축소용어집합 추출방법이 요구된다. 본 논문에서는 축소용어집합 추출방법을 크게 무작위 추출, 규칙에 의한 추출, 인간에 의한 직관적 추출 방법으로 구분하고 검색결과의 신뢰도 변화 형태를 분석한다.

• ETRI Journal
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• 제34권2호
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• pp.256-259
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• 2012

The double-base number system has been used in digital signal processing systems for over a decade because of its fast inner product operation and low hardware complexity. This letter proposes an innovative multiplier architecture using hybrid operands. The multiplier can easily be linked to flash analog-to-digital converters or digital systems through a double-base number encoder (DBNE) for realtime signal processing. The design of the DBNE and the multiplier enable faster digital signal processing and require less hardware resources compared to the binary processing method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.999-1000
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• 2006

The LDPC Code is focusing a powerful FEC(Forward Error Correction) codes for 4G Mobile Communication system. LDPC codes are used minimizing channel errors by modeling AWGN Channel as VDSL system. The performance of LDPC code is better than that of turbo code in long code word on iterative decoding algorithm. LDPC code are encoded by sparse parity check matrix. there are decoding algorithms for a LDPC code, Bit Flipping, Message passing, Sum-Product. Because LDPC Codes use low density parity bit, mathematical complexity is low and relating processing time becomes shorten.

• 제어로봇시스템학회논문지
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• 제13권12호
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• pp.1179-1185
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• 2007

This paper presents a new approach to automotive embedded systems development and validation. Recently automotive embedded systems become even more complex and the product life cycle is getting reduced. To overcome these problems AUTOSAR, a standardized software platform and component based approach, was introduced. Model-based approach has been widely applied in the development of embedded systems and has strong benefits such as early validation and automated testing. In this paper cooperative development and validation of AUTOSAR and model-based approach are introduced and automated testing techniques are proposed. With the proposed techniques we can improve complexity management through increased reuse and exchangeability of software module and automated testing is realized.

• 한국시뮬레이션학회논문지
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• 제12권1호
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• pp.59-71
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• 2003

Recently, a multi facility, multi product and multi period industrial problem has been widely investigated in Supply Chain Management (SCM). One of the key issues in the current SCM research area involves reducing both production and distribution costs. The purpose of this study is to determine the optimum quantity of production and transportation with minimum cost in the supply chain network. We have presented a mathematical model that deals with real world factors and constraints. Considering the complexity of solving such model, we have applied the genetic algorithm approach for solving this model using a commercial genetic algorithm based optimizer. The results for computational experiments show that the real size problems we encountered can be solved in reasonable time.

• 한국국방경영분석학회지
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• 제27권1호
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• pp.73-88
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• 2001

Designing high quality products and processes at a low cost is central technological and economic challenge to the engineer. The combination of engineering concepts and statistical implementations offered by Taguchi\`s off-line design technique has proven t be invaluable. By examining some deficiencies in designs from the Taguchi\`s highly fractional, orthogonal main effect plan based on orthogonal arrays, alternative method is proposed. The maximum resolution or the minimum aberration criterion is commonly used for selecting 2$^{n-m}$ fractional designs. We present new high resolution (low aberration) linear graphs to simplify the complexity of selecting designs with desirable statistical properties. The new linear graphs approach shows a substantial improvement over Taguchi\`s linear graphs and other related graphical methods for planning experiment. The new set of linear graphs will allow the experimenter to maintain the simple approach suggested by Taguchi while obtaining the best statistical properties of the resulting design such as minimum aberration as a by-product without dependency on complicated computational algorithm or additional statistical training.g.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.798-803
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• 2005

The increasing complexity of modem products requires the effective management of design knowledge, which partly resides in the product itself on the one hand. On the other hand, a lot of knowledge is gathered and/or generated during the design process, but disappears as the design project concludes. This paper describes a knowledge representation method to accommodate the implicit design knowledge. The method is based on the FBS(Function-Behavior-Structure) model and extends the object ontology with constraint entity. An example to represent the injection mold design knowledge is given to show its applicability.

• 산업융합연구
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• 제4권2호
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• pp.39-55
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• 2006

Pioneer brand and follower brand show differences in their perception of the environmental uncertainty. Market pioneer brand companies think that the environment is relatively simple and doesn't change much, whereas follower bland companies think that the environment is complicated and changes a lot. For market pioneer brand companies, among dynamism on the environment lever, there was less potential for the environment and parts, and government restrictions compared to follower brand companies. Also the complexity of the environment level complicated compared to the follower brand companies in areas such as competition for consumers with rival companies, materials, resources of equipment and parts, government restrictions, and the amount of change of the market's preference of the product.

• Journal of information and communication convergence engineering
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• 제20권1호
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• pp.1-7
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• 2022

Herein, a new space-time block coding technique is proposed for a MIMO 2 × 2 multiple-input multiple output (MIMO) system to minimize the bit error rate (BER) in Rayleigh fading channels with reduced decoding complexity using ZF and MMSE linear detection techniques. The main objective is to improve the service quality of wireless communication systems and optimize the number of antennas used in base stations and terminals. The idea is to exploit the correlation product technique between both information symbols to transmit per space-time block code and their own orthogonal Walsh-Hadamard sequences to ensure orthogonality between both symbol vectors and create a full-rate orthogonal STBC code. Using 16 quadrature amplitude modulation and the quasi-static Rayleigh channel model in the MATLAB environment, the simulation results show that the proposed space-time block code performs better than the Alamouti code in terms of BER performance in the 2 × 2 MIMO system for both cases of linear decoding ZF and MMSE.

• 시스템엔지니어링학술지
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• 제17권2호
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• pp.1-8
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• 2021

This study proposes a systems engineering approach for the development of an advanced planning & scheduling (APS) system for a cosmetic case manufacturing factory. The APS system makes production plans and schedules based on the injection process, which consists of 27 plastic injection machines in parallel to control recommended inventory of products. The system uses machine operation/failure information and defective product/work-in-process tracking information to support intelligent scheduling. Furthermore, a genetic algorithm model is applied to handle the complexity of heuristic rules and machine/quality constraints in this process. As a result of the development, the recommended inventory compliance rate is improved by scheduling the 30-day production plan for 15 main products.