• Title/Summary/Keyword: boolean function

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A Study on the Improvement of Performance of Concept-Based Information Retrieval Model Using a Distributed Subject Knowledge Base (주제별 분산 지식베이스에 의한 개념기반 정보검색시스템의 성능향상에 관한 연구)

  • 노영희
    • 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.

Material feature representation and identification with composite surfacelets

  • Huang, Wei;Wang, Yan;Rosen, David W.
    • Journal of Computational Design and Engineering
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    • v.3 no.4
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    • pp.370-384
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    • 2016
  • Computer-aided materials design requires new modeling approaches to characterize and represent fine-grained geometric structures and material compositions at multiple scales. Recently, a dual-Rep approach was developed to model materials microstructures based on a new basis function, called surfacelet. As a combination of implicit surface and wavelets, surfacelets can efficiently identify and represent planar, cylindrical, and ellipsoidal geometries in material microstructures and describe the distribution of compositions and properties. In this paper, these primitive surfacelets are extended and composite surfacelets are proposed to model more complex geometries. Composite surfacelets are constructed by Boolean operations on the primitives. The surfacelet transform is applied to match geometric features in three-dimensional images. The composition of the material near the identified features can then be modeled. A cubic surfacelet and a v-joint surfacelet are developed to demonstrate the reverse engineering process of retrieving material compositions from material images.

A Method for Computing the Network Reliability of a Computer Communication Network

  • Ha, Kyung-Jae;Seo, Ssang-Hee
    • Proceedings of the Korea Multimedia Society Conference
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    • 1998.10a
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    • pp.202-207
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    • 1998
  • The network reliability is to be computed in terms of the terminal reliability. The computation of a terminal reliability is started with a Boolean sum of products expression corresponding to simple paths of the pair of nodes. This expression is then transformed into another equivalent expression to be a Disjoint Sum of Products form. But this computation of the terminal reliability obviously does not consider the communication between any other nodes but for the source and the sink. In this paper, we derive the overall network reliability which all other remaining nodes. For this, we propose a method to make the SOP disjoint for deriving the network reliability expression from the system success expression using the modified Sheinman's method. Our method includes the concept of spanning trees to find the system success function by the Cartesian products of vertex cutsets.

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Fast Logic Minimization Algorithm for Programmable-Logic-Array Design (PLA 설계용 고속 논리최소화 알고리즘)

  • 최상호;임인칠
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.22 no.2
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    • pp.25-30
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    • 1985
  • This paper proposes an algorithm to simplify Boolean functions into near minimal sum-of-products for Programmable Logic Arrays. In contrast to the conventional procedures, where the execution time depends on the number of variables, the execution time by this procedure depends on the degree of consensus of base minterms. Thus as the number of variables is increased, the difference of CPU time becomes larger using this new Procedure than using other procedures and consequently the executable range of input function increasing. The algorithm has been implemented on CYEER 170-740 and it's results were compared with those using Arvalo's algorithm.

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Implementation of Hybrid Neural Network for Improving Learning ability and Its Application to Visual Tracking Control (학습 성능의 개선을 위한 복합형 신경회로망의 구현과 이의 시각 추적 제어에의 적용)

  • 김경민;박중조;박귀태
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.12
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    • pp.1652-1662
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    • 1995
  • In this paper, a hybrid neural network is proposed to improve the learning ability of a neural network. The union of the characteristics of a Self-Organizing Neural Network model and of multi-layer perceptron model using the backpropagation learning method gives us the advantage of reduction of the learning error and the learning time. In learning process, the proposed hybrid neural network reduces the number of nodes in hidden layers to reduce the calculation time. And this proposed neural network uses the fuzzy feedback values, when it updates the responding region of each node in the hidden layer. To show the effectiveness of this proposed hybrid neural network, the boolean function(XOR, 3Bit Parity) and the solution of inverse kinematics are used. Finally, this proposed hybrid neural network is applied to the visual tracking control of a PUMA560 robot, and the result data is presented.

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End-mill Manufacturing and Developing of Processing Verification via Cutting Simulation (Cutting Simulation을 이용한 End-milling Cutter의 제작 및 가공 검증 기술 개발)

  • Kim J.H.;Kim J.H.;Ko T.J.;Park J.W.;Kim H.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.453-454
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    • 2006
  • This paper describes a processing verification technique for developing about end-milling cutters. Developed software is processing verification module for manufacturing. By using cutting simulation method, we can obtain center points of finding wheel via Boolean operation between a grinding wheel and a cylindrical workpiece. The obtained CL data can be used for calculating NC data. After then, we can simulate by using designed grinding machine and NC data. This research has been implemented on a commercial CAD system by using the API function programming. The operator can evaluate the cutting simulation process and reduce the time of design and manufacturing.

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Performance-Driven Multi-Levelizer for Multilevel Logic Synthesis (다단 논리합성을 위한 성능 구동형 회로 다단기)

  • 이재흥;정정화
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.11
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    • pp.132-139
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    • 1993
  • This paper presents a new performance-driven multi-levelizer which transforms a two-level description into a boolean network of the multilevel structure satisfied with user's costraints, such as chip area, the number of wires and literals, maximum delay, function level, fanin, fanout, etc.. The performance of circuits is estimated by reference to the informations in cell library through the cell mapping phase, and multi-levelization of circuits is constructed by the decomposition using the kernel and factoring concepts. Here, the saving cost of a common subexpression is defined to the sum of area and delay saved, when it is substituted. The experiments with MCNC benchmarks show the efficiency of the proposed method.

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On the Cryptogeaphic Signigicance of Bent Functions (Bent 함수의 암호학적 성질에 관한 고찰)

  • 김광조
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.1 no.1
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    • pp.85-90
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    • 1991
  • After we introduce the properties of bent functions satisfying the SAC(Strict Avalanche Criterion), we made cldar the relationship between two functions, i.e., all Boolean functions satisfying the maximum order SAC. Bant function will be useful to implement cryptographic functions like S-boxes of block cipher, nonlinear combiners, etc. But due to thear 0/1 unbalance and their existence for only even number of input bits, bent functions have some restrictions to use as a building block for constructing bijective cryptographic functions.

Development of smart CAD/CAM system for machining center based on B-Rep solid modeling techniques(l) (A study on the B-Rep solid modeler using half edge data structure) (B-Rep 솔리드모델을 이용한 머시닝센터용 CAD/CAM시스템 개발(I))

  • Yang, Hee-Goo;Kim, Seok-Il
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.3
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    • pp.150-157
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    • 1996
  • In this paper, to develop a smart CAD/CAM system for systematically performing from the 3-D solid shape design of products to the CNC cutting operation of products by a machining center, a B-Rep solid modeler is realized based on the half edge data structure. Because the B-Rep solid modeler has the various capabilities related to the solid definition functions such as the creation operation of primitives and the translational and rotational sweep operation, the solid manipulation functions such as the split operation and the Boolean set operation, and the solid inversion function for effectively using the data structure, the 3-D solid shape of products can be easily designed and constructed. Also, besides the automatic generation of CNC code, the B-Rep solid modeler can be used as a powerful tool for realizing the automatic generation of finite elements, the interfer- ence check between solids, the structural design of machine tools and robots and so on.

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On Near Subtraction Semigroups (Near Subtraction Semigroups에 관한 연구)

  • Yon Yong-Ho;Kim Mi-Suk;Kim Mi-Hye
    • Proceedings of the Korea Contents Association Conference
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    • 2003.05a
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    • pp.406-410
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    • 2003
  • B. M. Schein([1]) considered systems of the form (${\Phi}$; ${\circ}$,-), where ${\Phi}$ is a set of functions closed under the composition "${\circ}$" of functions and the set theoretic subtraction "-". In this structure, (${\Phi}$; ${\circ}$) is a function semigroup and (${\Phi}$;-) is a subtraction algebra in the sense of [1]. He proved that every subtraction semigroup is isomorphic to a difference semigroup of invertible functions. Also this structure is closely related to the mathematical logic, Boolean algebra, Bck-algera, etc. In this paper, we define the near subtraction semigroup as a generalization of the subtraction semigroup, and define the notions of strong for it, and then we will search the general properties of this structure, the properties of ideals, and the application of it.

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