• Journal of Advanced Navigation Technology
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• v.15 no.5
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• pp.781-788
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• 2011

A sphere-packing problem is to find an arrangement of the spheres to fill as large area of the given space as possible, and covering problems are optimization problems which are dual problems to the packing problems. We generalize the concepts of the weight and the Hamming distance for a binary code to those of Boolean algebra. In this paper, we define a weight and a distance on a Boolean algebra and research some properties of the weight and the distance. Also, we prove the notions of the sphere-packing bound and the Gilbert-Varshamov bound on Boolean algebra.

• Journal of the Korean Society for information Management
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• v.13 no.1
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• pp.173-185
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• 1996

In this paper, we propose four optimizing methods for effectively processing queries in the Booleam information retrieval system ; (i) the short-circuit evaluation scheme used for optimizing logical expressions in programming lan-guages is applied to Boolean queries.(II) use the difference of the number of index word frequencies appearing in the related documents. (IIi) reduce the number of operators in the queries by applying the distribution law in the set theory. (iv) evaluate only once for the repeated expressions in the query. These methods have been implemented and tested in KRISTAL-II system on the UNIX workstation environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4597-4603
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• 2010

A factorization is a very important part of multi-level logic synthesis. The number of literals in a factored form is an estimate of the complexity of a logic function, and can be translated directly into the number of transistors required for implementation. Factored forms are described as either algebraic or Boolean, according to the trade-off between run-time and optimization. A Boolean factored form contains fewer number of literals than an algebraic factored form. In this paper, we present a new method for a Boolean factorization. The key idea is to identify two-cube nonkernel Boolean pairs from given expression. Experimental results on various benchmark circuits show the improvements in literal counts over previous other factorization methods.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2001.05a
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• pp.231-235
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• 2001

순수한 부울 검색 시스템은 문서와 질의 사이의 유사도를 나타내는 문서값을 계산할 수 없기 때문에, 검색된 문서들을 질의를 만족하는 정보에 따라 정렬할 수 없다. 부울 검색 시스템의 이러한 단점을 보완하는 방법으로 MMM 모델, Paice 모델, P-norm 모델이 개발되었다. 본 논문에서는 높은 검색 효과를 제공하는 질의분해 적합성 피드백(QSRF) 모델을 제안한다. 질의 분해 적합성 피드백 모델의 연산 특성이 MMM, Paice, P-norm 모델보다 우수함을 설명하고, 또한 성능 비교를 통하여 이를 입증한다.

• Proceedings of the Korea Association of Information Systems Conference
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• 1997.10b
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• pp.207-213
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• 1997

본 논문은 논리함수의 Module-2 방식에 따라 신경회로망을 구성하고, 구성된 신 경회로망에 의해서 논리함수 XOR을 예를 들어 표현하였다. 논리함수에서 사용된 Module-2 방식은 2치자료를 처리하는 것으로, 논리함수의 대표적인 것이 부울함수(Boole function)이 다. 신경회로망의 입력층에서는 논리함수의 값을 입력하고, 중간층에서는 논리함수의 직교 전개를 이용하고, 출력층에서도 직교전개등을 통하여 최종적인 결과값을 얻는 것이다. 이를 위해서 내적(inner product) 및 norm등을 정의하고, 직교(orthogonal)에 대한 정의를 하였 다. 또한, 부울함수(Boole Function)의 미분에 대한 정의 및 부울함수의 Maclaurin 전개에 대해서도 정의하였다. 본 논문에서 논리함수의 최종적인 출력값은 부울함수의 Maclaurin 전 개에 의해서도 실제적인 값이 출력될 수 있다는 것을 나타내었다.

• Journal of the Korea Computer Industry Society
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• v.8 no.4
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• pp.229-236
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• 2007

A factored form is a sum of products of sums of products, ..., of arbitrary depth. Factoring is the process of deriving a parenthesized form with the smallest number of literals from a two-level form of a logic expression. The factored form is not unique and described as either algebraic or Boolean. A Boolean factored form contains fewer number of literals than an algebraic factored form. In this paper, we present a new method for a Boolean factorization. The key idea is to identify two-cube Boolean subexpressions from given two-level logic expression and to extract divisor/quotient pairs. Then, we derive extended divisor/quotient pairs, where their quotients are not cube-free, from the generated divisor/quotients pairs. We generate quotient/quotient pairs from divisor/quotient pairs and extended divisor/quotient pairs. Using the pairs, we make a matrix to generate Boolean factored form based on a technique of rectangle covering.

• Journal of Korea Port Economic Association
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• v.38 no.3
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• pp.1-13
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• 2022

The Busan-Ulsan-Gyeongsangmando(BuUlGyeong) megacity aims to grow into the second metropolitan area by strengthening the growth and connectivity of the southeast region in Korea. In order to analyze the linkage between port logistics and regional economic development, this study focused on the economic community of BuUlGyeong. The findings are as follows. First, it was found that vessel entry and departure had a positive (+) significant effect on cargo volume. Second, the cargo volume was found to have a preemptive effect on the vessel entry and exit ports and the composite index. Third, the composite Index was found to have a significant positive (+) effect on cargo volume. From the results of the variance decomposition, it can be confirmed that the composite index has a weak impact on ship entry/exit and cargo volume. Based on the above findings, some policy implications are derived. First, regional governments in BuUlGyeong should provide incentives to revitalize the maritime economy such as the expansion of maritime port infrastructure and encouraging investment. Second, since an increase in cargo transport volume at major national ports linked to the BuUlGyeong region has a positive (+) effect on economy. Therefore it is necessary to expand actively port marketing and regular service for the country and ports. Third, investments should be made continuously to expand the marine port infrastructure such as the expansion of facilities so that global shipping companies can continue to call megacities in BuUlGyeong ports for super-large ships and cruises.

• Proceedings of the Korea Contents Association Conference
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• 2018.05a
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• pp.381-382
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• 2018

격자함의 대수와 헤이팅 대수는 부울 대수를 일반화한 논리체계이며 논리적 함의(${\rightarrow}$)를 이항연사자로 갖는 대수적 체계를 갖는다. 본 논문에서는 격자함의 대수와 헤이팅 대수가 서로 다른 대수체계를 갖는다는 것을 예로 보이고, 이들의 차이점을 조사한다. 또한 격자함의 대수, 헤이팅 대수, 그리고 부울 대수의 관계를 알아본다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.3
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• pp.597-604
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• 2001

In conventional boolean retrieval systems, document ranking is not supported and similarity coefficients cannot be computed between queries and documents. The MMM, Paice and P-norm models have been proposed in the past to support the ranking facility for boolean retrieval systems. They have common properties of interpreting boolean operators softly. In this paper we propose a new soft evaluation method for Information retrieval using query splitting relevance feedback model. We also show through performance comparison that query splitting relevance feedback(QSRF) is more efficient and effective than MMM, Paice and P-norm.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.745-751
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• 2004

In conventional boolean retrieval systems, document ranking is not supported and similarity coefficients cannot be computed between queries and documents. The MMM(Max and Min Model), Paice and P-norm models have been proposed in the past to support the ranking facility for boolean retrieval systems. They have common properties of interpreting boolean operators softly In this paper we propose a new soft evaluation method for web Information retrieval using local context analysis feedback model. We also show through performance comparison that local contort analysis feedback is more efficient and effective than MMM, Paice and P-norm.