• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.2
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• pp.65-76
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• 2002

Shin et al. proposed the new hash function with 160-bit output length at PKC'98. This hash function is based on the advantages of the existing hash functions, such as SHA-1, RIPEMD-160, HAVAL, and etc.$^{[1]}$ Recently, Han et al. cryptanalyzed the hash function proposed at PKC'98 and proposed the method finding a collision pair with $2^{-30}$ probability at FSE 2002, supposing that boolean functions satisfy SAC(Strict Avalanche Criterian).$^{[2]}$ This paper improves the method and shows that we can find a collision pair from the original version of the hash function with $2^{-37.13}$ probability through the improved method. And we point out that the problem of the function comes from shift values dependent on message.

• Journal of information and communication convergence engineering
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• v.5 no.2
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• pp.131-135
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• 2007

In this paper, The proposed algorithm consists of three steps. In the first step, TD(Transition Density) calculation has to be performed. a CLB-based CPLD low-power technology mapping algorithm considered a Trade-off is proposed. To perform low-power technology mapping for CPLDs, a given Boolean network has to be represented in a DAG. Total power consumption is obtained by calculating the switching activity of each node in a DAG. In the second step, the feasible clusters are generated by considering the following conditions: the number of inputs and outputs, the number of OR terms for CLB within a CPLD. The common node cluster merging method, the node separation method, and the node duplication method are used to produce the feasible clusters. In the final step, low-power technology mapping based on the CLBs packs the feasible clusters. The proposed algorithm is examined using SIS benchmarks. When the number of OR terms is five, the experiment results show that power consumption is reduced by 30.73% compared with TEMPLA, and by 17.11 % compared with PLA mapping.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.709-711
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• 2005

이 논문에서는 CATIA, PRO-E 등의 CAD에서 3D 모델을 생성할 때 사용하는 파라메트릭 솔리드 모델링 기법에서 일반적으로 사용하는 방법보다 모델링 데이터의 용량을 크게 줄일 수 있는 방법에 대하여 고찰한다. 3D 파라메트릭 솔리드 모델링 기법은 기본적인 상세 솔리드들을 생성하여 부울(Boolean) 연산으로 이들을 조합하여 복잡한 형상(geometric object)을 만드는데 이 과정에서 많은 부울 연산이 수행된다. 그런데 각각의 상세 솔리드들의 크기가 필요 이상으로 크게 만들어 짐으로써 생성된 모델의 데이터 용량이 방대하게 되고 생성시간에도 영향을 미친다. 여기에서는 실무 경험을 바탕으로 처음에 생성된 상세 솔리드의 불필요한 부분을 제거하여 부울 연산에 알맞은 크기로 변경하여 모델링 데이터의 용량을 줄이는 방법을 제안한다.

• Journal of the Korean Society for information Management
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• v.19 no.1
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• pp.47-69
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• 2002

The concept based retrieval model has shown a higher performance than those of the simple matching function method or the P-norm retrieval method introduced to compensate the demerits of the Boolean retrieval model. However. it takes too long to create a semantic-net knowledge base, which is essential in concept exploration. In order to solve such demerits. a method was sought out by creating a distributed knowledge base by subjects to reduce construction time without hindering the performance of retrieval.

• Honam Mathematical Journal
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• v.37 no.2
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• pp.187-205
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• 2015

We discuss the relationship between interval-valued fuzzy ideals and interval-valued fuzzy congruence on a distributive lattice L and show that for a generalized Boolean algebra the lattice of interval-valued fuzzy ideals is isomorphic to the lattice of interval-valued fuzzy congruences. Finally we consider the products of interval-valued fuzzy ideals and obtain a necessary and sufficient condition for an interval-valued fuzzy ideal on the direct sum of lattices to be representable as a direct sum of interval-valued fuzzy ideals on each lattice.

• Honam Mathematical Journal
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• v.42 no.2
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• pp.251-268
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• 2020

In this paper, we estimate the degree of approximation by means of the complete modulus of continuity, the partial modulus of continuity, the Lipschitz-type class and Petree's K-functional for the bivariate Szász-Kantorovich operators based on Brenke-type polynomials. Later, we construct Generalized Boolean Sum operators associated with combinations of the Szász-Kantorovich operators based on Brenke-type polynomials. In addition, we obtain the rate of convergence for the GBS operators with the help of the mixed modulus of continuity and the Lipschitz class of the Bögel continuous functions.

• Journal of the Chungcheong Mathematical Society
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• v.10 no.1
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• pp.43-56
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• 1997

In this paper, we introduce a new class of ${\delta}$-frames and study its properties. To do so, we introduce ${\delta}$-filters, almost Lindel$\ddot{o}$f frames and Lindel$\ddot{o}$f frames. First, we show that a complete chain or a complete Boolean algebra is a ${\delta}$-frame. Next, we show that a ${\delta}$-frame L is almost Lindel$\ddot{o}$f iff for any ${\delta}$-filter F in L, ${\vee}\{x^*\;:\;x{\in}F\}{\neq}e$. Last, we show that every regular Lindelof ${\delta}$-frame is normal and a Lindel$\ddot{o}$f ${\delta}$-frame is preserved under a ${\delta}$-isomorphism which is dense and codense.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.29B no.11
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• pp.56-64
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• 1992

The sum-of-product type MVL (Multiple-valued logic) functions can be directly transformed into the exclusive-sum-of-literal-product(ESOLP) type MVL functions with a substitution of the OR operator with the exclusive-OR(XOR) operator. This paper presents an algorithm that can reduce the number of minterms for the purpose of minimizing the hardware size and the complexity of the circuit in the realization of ESOLP-type MVL functions. In Boolean algebra, the joinable true minterms can form the cube, and if some cubes form a cube-chain with adjacent cubes by the insertion of false cubes(or, false minterms), then the created cube-chain can become a large cube which includes previous cubes. As a result of the cube grouping, the number of minterms can be reduced artificially. Since ESOLP-type MVL functions take the MIN/XOR structure, a XOR circuit and a four-valued MIN/XOR dynamic-CMOS PLA circuit is designed for the realization of the minimized functions, and PSPICE simulation results have been also presented for the validation of the proposed algorithm.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.6
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• pp.43-47
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• 1978

This paper presents a technique for symbolic reliability analysis of a general communication network. All simple paths are determined, then they are easily modified to be mutually disjoint by the specific Boolean expressions. A computer program for Binding all of the simple paths between two terminals is also developed. The examples are given to illustrate the technique.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06c
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• pp.258-261
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• 1994

자연언어 인터페이스는 초보자나 비숙련가의 입장에서는 새로운 시스템의 적응에 있어서 어떤 학습도 필요하지 않다는 장점이 있다. 이 연구에서는 불리언 질의를 처리하는 정보검색 시스템의 자연언어 인터페이스를 구혐하였다. 즉, 한국어 자연언어 질의를 불리언 질의로 변환해주는 시스템이다. 접근 방법은 먼저 자연언어 질의를 구문 해석한 후에, 그 결과인 문자의 의존 구조와 불용어 정보를 사용하여 기본적인 불리언 질의를 만든다음, 시소러스를 이용하여 불리언 질의를 확장한다. 여기에서 사용한 구문 해석 방법은 기존 문법에 기반한 방법이다. 변환 시스템은 SPARC-II 호환기종에서 구현되었으며, 약 5만 단어의 사전을 사용한다. 가공된 120 개의 질의를 대상으로 실험한 결과, 전체 소요시간은 13.5초가 걸렸다. 그리고, 변환된 불리언 연산식중에 110개가 적절하게 변환된 것으로 조사되었다.