• Journal of the Korean Society for information Management
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• v.10 no.1
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• pp.31-52
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• 1993

This study compared the retrieval effectiveness of conventional Boolean and fuzzy set retrieval strategies through a retrieval experiment. The recall ratio of fuzzy set retrieval is 75%, higher than the 60% of Boolean retrieval. On the other hand, the precision ratio of fuzzy set retrieval is 69%, a little bit lower than the 73% of Boolean retrieval.

• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.4
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• pp.141-149
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• 1998

One of the difficulties in using the current Boolean-based information retrieval systems is that it is hard for a user, especially a novice, to formulate an effective Boolean query. One solution to this problem is to let the system formulate a query for a user from his relevance feedback documents in this research, an intelligent query reformulation mechanism based on ID3 is proposed and the sensitivity of its retrieval effectiveness, i.e., recall, precision, and E-measure, to various input settings is analyzed. The parameters in the input settings is the number of relevant documents. Experiments conducted on the test set of Medlars revealed that the effectiveness of the proposed system is in fact sensitive to the number of the initial relevant documents. The case with two or more initial relevant documents outperformed the case with one initial relevant document with statistical significances. It is our conclusion that formulation of an effective query in the proposed system requires at least two relevant documents in its initial input set.

• The Journal of Information Technology
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• v.9 no.3
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• pp.27-32
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• 2006

If is interested and create rule between it in item that association rules buys, by negative association rules is interested to item that do not buy, it is attempt to do data Maining more effectively. It is difficult that existent methods to find negative association rules find one part of rule, or negative association rules because use more complicated algorithm than algorithm that find association rules. Therefore, this paper presents method to create negative association rules by simpler process using Boolean Analyzer that use dependency between items. And as Boolean Analyzer through an experiment, show that can find negative association rules and more various rule through comparison with other algorithm.

• The Journal of Korean Association of Computer Education
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• v.15 no.1
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• pp.65-72
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• 2012

Generally, a logic function has many factored forms. The problem of finding more compact factored form is one of the basic operations in logic synthesis. In this paper, we present a new method for factoring Boolean functions to assist in educational logic designs. Our method for factorization is to implement two-cube Boolean division with supports of an expression. The number of literals in a factored form is a good estimate of the complexity of a logic function. Our empirical evaluation shows the improvements in literal counts over previous other factorization methods.

• Journal of applied mathematics & informatics
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• v.7 no.1
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• pp.269-278
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• 2000

A Boolean function generates a binary sequence which is frequently used in a stream cipher. There are number of critical concepts which a Boolean function, as a key stream generator in a stream cipher, satisfies. These are nonlinearity, correlation immunity, balancedness, SAC(strictly avalanche criterion), PC(propagation criterion) and so on. In this paper, we present the algorithms for generating random nonlinear combining functions satisfying given correlation immune order and nonlinearity. These constructions can be applied for designing the key stream generators. We use Microsoft Visual C++6.0 for our program.

• Bulletin of the Korean Mathematical Society
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• v.44 no.4
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• pp.721-729
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• 2007

In this paper, we have characterizations of idempotent matrices over general Boolean algebras and chain semirings. As a consequence, we obtain that a fuzzy matrix $A=[a_{i,j}]$ is idempotent if and only if all $a_{i,j}$-patterns of A are idempotent matrices over the binary Boolean algebra $\mathbb{B}_1={0,1}$. Furthermore, it turns out that a binary Boolean matrix is idempotent if and only if it can be represented as a sum of line parts and rectangle parts of the matrix.

• Korean Journal of Computational Design and Engineering
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• v.10 no.3
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• pp.151-161
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• 2005

This paper describes the parting and Boolean operations for a pseudo-solid model of a plastic part, and their application to injection mold design. Here, a pseudo-solid model means a sheet model that looks like a solid model, but its boundary is not closed. When a solid model created in a different CAD system is imported through a standard data exchange file format, in most cases, a pseudo-solid model may be created due to tolerance or some other problems. However, most existing mold design systems based on solid modeling kernels require a complete part solid model. Therefore, mold designers have to do time-consuming healing operations to convert a pseudo-solid to solid. To eliminate or reduce the healing pre-process for mold design, in this paper, we proposed the parting and Boolean Operations on pseudo-solid part models. This paper also describes their detailed implementation and a case study.

• Journal of the Korean Society for information Management
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• v.18 no.2
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• pp.7-30
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• 2001

The characteristics of the short document representatives and short queries of OPAC systems need the different ranking algorithms from IR systems. This study tested and analyzed the effectiveness of four sorting schemes and four ranking algorithms and the six effectiveness measurements for the ranked Boolean OPAC systems. The sorting by publication year was better but without significant difference. The cover density ranking was significantly better than the frequency-based ranking of the Fuzzy or DNF models. The simple effectiveness measurement based on the average rank of relevant documents retrieved was as good as the others and better than the precision P.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.5
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• pp.1785-1800
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• 2014

In 2011, Chen and Wu proposed their method of sharing n secret images to n+1 shadow images through the concept of a Boolean-based Visual Secret Sharing (VSS) method. However, the shadow images produced by this method are not equally important. If the participant who owns an important shadow image does not want to cooperate with other participants, most secret images can not be reconstructed. In the proposed method, the relationship between the shadows images and secret images are designed in a circular way mostly. Each shadow image only relates to two secret images. This means that if one participant refuses to cooperate with other participants, there are only two secret images which can not be reconstructed. Moreover, our proposed method only needs to produce n shadow images and n secret images can be shared to them.

• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.1-8
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• 1997

The main purpose of the Boolean equivalence problem is to verify that two Boolean expressions have the same functionality. Simulation has been extensively used as the standard method for the equivalence problem. Obviously, the number of tests required to perform a satisfactory coverage grows exponentially with the number of input variables. However, formal methods as opposed to simulation are getting more attention from the community. We propose a new algorithm called the Cover-Merge Algorithm based on a derivational method using the concept of cover and merge for the equivalence problem and investigate its theoretical aspects. Because of the difficulty of the problem, we emphasize simplification techniques in order to reduce the search space or problem size. Heuristics based on types of merges are developed to speed up the derivation process by allowing simplifications. In comparison with widely used technique called Binary Decision Diagram or BDD, the algorithm proposed outperforms BDD in nearly all cases of input including standard benchmark problems.