• 제목/요약/키워드: Computational Logic

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Rule 선택 기법을 사용한 Type-1 Fuzzy Logic Controller의 연산 효율성 향상 (Enhancement of Computational Efficiency for Type-1 Fuzzy Logic Controller Using Rule Selection Method)

  • 조정우;박귀태
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1879_1880
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    • 2009
  • 본 논문에서는 제어상황에 따라 Type-1 Fuzzy Logic Controller가 선택적으로 rule을 사용하도록 rule 선택 알고리즘을 제안 한다. 그리고 이를 통해 연산 효율성을 높이는 방법에 관해 논한다. Type-1 Fuzzy Logic Controller는 기존의 제어기에 비해 설계하기 쉽고 성능이 더 뛰어나다. 그러나 제어 변수가 많아질수록 rule의 개수가 늘어나 연산량이 증가하게 된다. 연산량이 많아지면 고성능의 컴퓨터에서는 실시간 연산에 문제가 없으나 산업용 micro controller에서는 실시간 연산을 구현하는데 한계가 발생한다. 본 논문에서는 Type-1 Fuzzy Logic System의 논리구조에 근거하여 Type-1 Fuzzy Logic Controller의 연산량을 감소시킬 수 있는 알고리즘을 제안한다. 제안한 알고리즘은 제어상황에 따라 필요한 rule들만 선택적으로 제어값 도출을 위한 연산에 관여하도록 한다. Matlab 시뮬레이션을 통해 제안한 알고리즘의 유용성과 연산량을 실험하였다. 실험대상은 2륜 이동로봇으로 하였고 step 응답과 전/후진 시 결과를 관찰하였다. 실험 결과 제안한 알고리즘이 기존의 Type-1 Fuzzy Logic Controller에 비해 제어상황에 따라 필요한 rule들만 선택적으로 사용하는 것을 확인하였다. 결과적으로 연산 효율성이 향상되었다.

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SPIN HALF-ADDER IN 𝓑3

  • HASAN KELES
    • Journal of Applied and Pure Mathematics
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    • 제5권3_4호
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    • pp.187-196
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    • 2023
  • This study is about spin half add operations in 𝓑2 and 𝓑3. The burden of technological structures has increased due to the increase in the use of today's technological applications or the processes in the digital systems used. This has increased the importance of fast transactions and storage areas. For this, less transactions, more gain and storage space are foreseen. We have handle tit (triple digit) system instead of bit (binary digit). 729 is reached in 36 in 𝓑3 while 256 is reached with 28 in 𝓑2. The volume and number of transactions are shortened in 𝓑3. The limited storage space at the maximum level is storaged. The logic connectors and the complement of an element in 𝓑2 and the course of the connectors and the complements of the elements in 𝓑3 are examined. "Carry" calculations in calculating addition and "borrow" in calculating difference are given in 𝓑3. The logic structure 𝓑2 is seen to embedded in the logic structure 𝓑3. This situation enriches the logic structure. Some theorems and lemmas and properties in logic structure 𝓑2 are extended to logic structure 𝓑3.

직관 실험 및 코퍼스를 바탕으로 한 의미 중의성 해소 계산 모형 연구 (A Study on the Computational Model of Word Sense Disambiguation, based on Corpora and Experiments on Native Speaker's Intuition)

  • 김동성;최재웅
    • 인지과학
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    • 제17권4호
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    • pp.303-321
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    • 2006
  • 본 논문은 의미 중의성 해소에 대한 화자의 직관의 계산 모형에 대한 연구로 Harris (1964)의 '분포가설'에 근거하여 핵심어와 공기하는 어휘들에 대한 분포적 정규성을 포착하는 언어 직관의 계산 모형을 제안한다. 이를 위해 분포적 정규성에 대한 화자의 처리 계산 모형을 파악하기 위하여 심리언어학적 실험을 실시하고 그 결과를 분석한다. 계산 모형으로는 논리 모형, 확률 모형, 그리고 확률 추론 모형의 세가지 모형이 설정되었다. 실험은 두 가지로 구성되었다. 첫 번째는 100만 어절 코퍼스에서 추출된 문장을 화자 직관으로 의미를 식별하는 실험이었다. 이 실험에서는 응답간 일치도가 98%로 나왔다. 두 번째 실험은, 제한된 환경에서 실험자의 반응을 관찰하기 위한 것으로, 분열문이라는 환경을 통해 핵심어와 공기어사이의 의미 관계를 살펴보았다. 또한 100만 어절 코퍼스에서 관찰된 수치와 실험에서 관찰된 관찰치사이의 상관성을 피어슨의 상관계수로 측정하였다. 그러한 측정 결과 실제 코퍼스에서 관찰되는 현상은 논리모형과 상관성이 있었고, 제한된 환경에서 실시한 결과는 확률 모형과 상관성이 있었다. 이 실험결과는 논리 모형이 우선적으로 의미 분류에 관여하나, 만약 논리 모형이 적용되지 않을 경우 확률 모형이 관여함을 보여 준다. 아울러 의미 결정 모형의 관점에서는 논리 모형이 정확하게 직관모형을 예측할 수 있었고, 확률추론 모형도 직관모형을 근사치에 가깝게 예측할 수 있었다.

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How has belief modality contributed to formal semantics?

  • Tojo, Satoshi
    • 한국언어정보학회:학술대회논문집
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    • 한국언어정보학회 2007년도 정기학술대회
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    • pp.42-53
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    • 2007
  • Looking back the history of formal treatment of linguistics, we cannot disregard the contribution of possible world semantics. Intensional logic of Montague semantics, DRT (Discourse Representation Theory), mental space, and situation theory are closely related to or compared with the notion of possible world. All these theories have commonly clarified the structure of belief context or uncertain knowledge, employing hypothesized worlds. In this talk, I firstly brief the pedigree of these theories. Next, I will introduce the recent development of modal logic for the representation of (i) knowledge and belief and (ii) time, in which belief modality is precisely discussed together with the accessibility among possible worlds. I will refer to BDI (belief-desire-intention) logic, CTL (computational tree logic), and sphere-based model in belief revision. Finally, I will discuss how these theories could be applied to the further development of analyses of natural language.

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Logic circuit design for high-speed computing of dynamic response in real-time hybrid simulation using FPGA-based system

  • Igarashi, Akira
    • Smart Structures and Systems
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    • 제14권6호
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    • pp.1131-1150
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    • 2014
  • One of the issues in extending the range of applicable problems of real-time hybrid simulation is the computation speed of the simulator when large-scale computational models with a large number of DOF are used. In this study, functionality of real-time dynamic simulation of MDOF systems is achieved by creating a logic circuit that performs the step-by-step numerical time integration of the equations of motion of the system. The designed logic circuit can be implemented to an FPGA-based system; FPGA (Field Programmable Gate Array) allows large-scale parallel computing by implementing a number of arithmetic operators within the device. The operator splitting method is used as the numerical time integration scheme. The logic circuit consists of blocks of circuits that perform numerical arithmetic operations that appear in the integration scheme, including addition and multiplication of floating-point numbers, registers to store the intermediate data, and data busses connecting these elements to transmit various information including the floating-point numerical data among them. Case study on several types of linear and nonlinear MDOF system models shows that use of resource sharing in logic synthesis is crucial for effective application of FPGA to real-time dynamic simulation of structural response with time step interval of 1 ms.

A Semantic Network Approach to PPO (Products, Processes, Organizations/Resources) Modeling for PDM Systems

  • Hyo-Won Suh;Heejung Lee;Seungchul Ha
    • 한국CDE학회논문집
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    • 제4권3호
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    • pp.238-246
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    • 1999
  • The modeling method to support product development processes (PDP) must have certain characteristics including the ability to represent multiple viewpoints of the product development and integrate with currently available analysis and design methods based on CE concept. This paper describes the reference model to support multiple viewpoints (PPO: Products, Processes, and Organizations/Resources viewpoints) of the product development processes, from which each model (Products model, Processes model, and Organizations/Resources model) can be extracted, as well as produces PPO data schema. This reference model has associative relationships among the products, processes, and organizations/resources. To allow the extensibility to support design evolution, we propose structured dat representation methods using semantic network, which can be constructed through first-order logic. The product development processes is so represented by specifying entities and semantic relationships among them hat he appropriate information can be accessed and all of the relevant attributes about the entities can be retrieved simultaneously.

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제품개발을 위한 온톨로지 기반 지식 프레임워크 (Ontology-based Knowledge Framework for Product Development)

  • 서효원;이재현
    • 한국CDE학회논문집
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    • 제11권2호
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    • pp.88-96
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    • 2006
  • This paper introduces an approach to ontology-based framework for knowledge management in a product development domain. The participants in a product life cycle want to share the product knowledge without any heterogeneity. However, previous knowledge management systems do not have any conceptual specifications of their knowledge. We suggest the three levels of knowledge framework. First level is an axiom, which specifies the semantics of concepts and relations. Second level is a product development knowledge map. It defines the common domain knowledge which domain experts agree with. Third level is a specialized knowledge for domain, which includes three knowledge types; expert knowledge, engineering function and data-analysis-based knowledge. We propose an ontology-based knowledge framework based on the three levels of knowledge. The framework has a uniform representation; first order logic to increase integrity of the framework. We implement the framework using prolog and test example queries to show the effectiveness of the framework.

CPC 환경을 위한 Product 온톨로지 기반 의미 공유 접근법 (An Approach to Semantic Mapping using Product Ontology for CPC Environment)

  • 김경영;서효원
    • 한국CDE학회논문집
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    • 제9권3호
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    • pp.192-202
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    • 2004
  • This paper introduces an approach to semantic mapping using Product ontology for CPC environment. In CPC environment, it is necessary that the participants in a product life cycle should share the same understanding about the semantic of product terms. For example, they should know that although 'COMPONENT' and 'ITEM' are different word-expressions, they could have the same meaning. In order to handle such terms in the information system, it is desirable that the system automatically recognizes that the terms have the same semantics. Serving this purpose, we described an ontology design methodology using first order logic, knowledge interchange format, and knowledge engineering process. In our approach, we investigated domain knowledge of the Bill Of Material, and then designed Product ontology of it. Based on the ontology, we described syntactic translation, semantic translation, and semantic mapping procedure with an example.

공작기계의 유연 다물체 동역학 및 제어기 연계해석 (Coupled Flexible Multi-Body Dynamics and Controller Analysis of Machine Tool)

  • 김동만;김동현;박강균;최현철
    • 한국생산제조학회지
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    • 제19권3호
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    • pp.307-312
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    • 2010
  • In this study, advanced computational technique for mechatronic analysis has been developed for the efficient design and test of typical machine tool models. Flexible multi-body dynamic (FMBD) analysis method combined with motion controller including control logics is used to simulate typical operation conditions. The present FMBD machine tool model is composed of flexible column structure, rigid body spindle, vertical motion guide (arm) and screw elements. Driving motor clement with rotating degree-of-freedom is interconnected and governed by the designed Matlab Simulink control logic, and then the position of the spindle is feedback into the control logic. It is practically shown from the results that the investigation of designed machine tools with controller can be effectively conducted and verified.

Logical 모델을 활용한 자동차 차체 조립 라인의 시뮬레이션 적용을 위한 방안 연구 및 적용 (A Study and Application of Methodology for Applying Simulation to Car Body Assembly Line using Logical Model)

  • 구락조;박상철;왕지남
    • 한국CDE학회논문집
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    • 제14권4호
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    • pp.225-233
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    • 2009
  • The objective of this paper is to examine a construction method and verify PLC logic using the logical modeling and simulation of a virtual plant has complex manufacturing system and the domain of application is car body assembly line of automotive industrial operated by PLC Program. The proposed virtual plant model for the analysis of the construction method consists of three types of components which are virtual device, intermediary transfer and controller is modeled by logical model but it the case of the verification of PLC program, HMI and PLC logic in the field substitute for the controller. The implementation of the proposed virtual plant model is conducted PLC Studio which is an object-oriented modeling language based on logical model. As a result, proposed methods enable 3D graphics is designed in the analysis step to use for verification of PLC program without special efforts.