• 제목/요약/키워드: Local rule

검색결과 335건 처리시간 0.018초

국부 변형률 근사를 이용한 원통형 노치시편의 피로균열 발생수명의 예측 (The Prediction of Fatigue Crack Initiation Life of Cylindrical Notch Specimens Using Local Strain Approximation)

  • 임재용;홍성구;이순복
    • 대한기계학회논문집A
    • /
    • 제28권6호
    • /
    • pp.791-798
    • /
    • 2004
  • Fatigue crack initiation lives of round cylindrical notch specimen were investigated. Firstly, local strain approximation methods, such as the modified incremental Neuber's rule and the modified incremental Glinka's equivalent strain energy density(ESED) rule, were used to get multiaxial stress and strain state components at the notch tip. Based on the history of local stress and strain, multiaxial fatigue models were used to obtain fatigue crack initiation lives. Because the solution of Neuber's rule and Glinka's ESED rule make the upper and lower bound of local strain approximations, fatigue crack initiation lives are expected to place between life predictions by two local strain approximations. Experimental data were compared with the fatigue crack initiation life prediction results.

VLSI 게이트 레벨 논리설계 최적화를 위한 Rule-Based 시스템 (A Rule-Based System for VLSI Gate-Level Logic Optimization)

  • 이성봉;정정화
    • 대한전자공학회논문지
    • /
    • 제26권1호
    • /
    • pp.98-103
    • /
    • 1989
  • 본 논문에서는 게이트 레벨에서 논리 최적화를 하기 위한, 새로운 시스템을 제안한다. 본 시스템은 회로의 일부분을 간략화된 등가회로로 대치하는 local transformation을 rule로 표현한 rule-based 시스템이다. 본 시스템에서는 효율적인 패턴매칭을 위해, 'rule의 일반화'와 '국소최적화'를 제안한다. Rule의 일반화는 패턴매칭시 회로탐색을 줄이기 위해 사용되며, 국소최적화는 불필요한 회로탐색을 배제하기 위해 사용된다. 또한, 불필요한 패턴매칭 시도를 줄이기 위해, 회로 패턴의 매칭순서를 rule 기술에 포함시킨다. 또한, 본 시스템을 하드웨어 컴파일러에 의해 생성된 논리회로 최적화에 적용하여, 그 효용성을 보인다.

  • PDF

Local Rule of Đại Việt under the Lý Dynasty: Evolution of a Charter Polity after the Tang-Song Transition in East Asia

  • Momoki, Shiro
    • Asian review of World Histories
    • /
    • 제1권1호
    • /
    • pp.45-84
    • /
    • 2013
  • Empirical research into Đại Việt before the $14^{th}$ century has made little progress since the 1990s. To improve this situation, I here examine how the L$\acute{y}$ dynasty (1009-1226), the first long-lasting dynasty of Đại Việt, established stable local ruleafter the "Tang-Song Transition" in China that changed the entire picture of East Asia (including both Southeast and Northeast Asia). This paper focuses on two issues. First are the local administrative units and their governors. The nature of both higher units like lộ(circuits), phủ and ch$\hat{a}$u (provinces), and basic units like hươg and gi$\acute{a}$p (districts?) will be examined. Second, I examine non-institutional channels of local rule by the imperial family. By combining such administrative and non-administrative means, the L$\acute{y}$ central court enforced a considerably stable local rule for two centuries. Finally, I attempt some preliminary comparisons with the local rule of Goryeo (918-1392) in the Korean peninsula, a polity that shared many features with Đại Việt in the process of localization of the Tang and Song models. I hope this approach of viewing small empires from the standpoint not of their "goal" (modern states) but of their "start" (charter polities), will enrich the discussion of East Asian small empires.

Three-dimensional structural design based on cellular automata simulation

  • Kita, E.;Saito, H.;Tamaki, T.;Shimizu, H.;Xie, Y.M.
    • Structural Engineering and Mechanics
    • /
    • 제23권1호
    • /
    • pp.29-42
    • /
    • 2006
  • This paper describes the design scheme of the three-dimensional structures based on the concept of the cellular automata simulation. The cellular automata simulation is performed according to the local rule. In this paper, the local rule is derived in the mathematical formulation from the optimization problem. The cell density is taken as the design variable. Two objective functions are defined for reducing the total weight of the structure and obtaining the fully stressed structure. The constraint condition is defined for defining the local rule. The penalty function is defined from the objective functions and the constraint condition. Minimization of the penalty function with respect to the design parameter leads to the local rule. The derived rule is applied to the design of the three-dimensional structure first. The final structure can be obtained successfully. However, the computational cost is expensive. So, in order to reduce the computational cost, the material parameters $c_1$ and $c_2$ and the value of the cell rejection criterion (CRC) are changed. The results show that the computational cost depends on the parameters and the CRC value.

인지 통신에서 1차 사용자의 판단 시간을 줄이기 위한 Or 기법의 연구 (A Study of the Or rule to reduce decision time of Primary User at the Cognitive radio)

  • 최문근;공형윤
    • 한국인터넷방송통신학회논문지
    • /
    • 제10권5호
    • /
    • pp.161-166
    • /
    • 2010
  • 기존의 OR 법칙은 각각의 2차 사용자가 검출한 결과 값을 퓨전센터에서 취합하여 1차 사용자의 존재 유무를 판단한다. 따라서 기존의 OR 법칙은 1차 사용자의 존재 유무를 판단하기 위해서 CR 네트워크 내에 존재하는 모든 2차 사용자로부터 검출 결과 값을 취합하여야 했다. 하지만 본 논문을 통해 제안하는 OR 법칙은 2차 사용자의 검출 결과 값에 따라 퓨전센터에서 취합하는 2차 사용자의 검출 결과 값의 수를 조절하여 2차 사용자의 전송 용량을 높일 수 있다. 그리고 본 논문을 통해 제안하는 OR 법칙의 시뮬레이션을 통해 기존의 OR 법칙과 제안하는 OR 법칙의 오 경보 확률, 미 검출 확률을 구하고 전송 용량을 구한다.

Energy and force transition between atoms and continuum in quasicontinuum method

  • Chang, Shu-Wei;Liao, Ying-Pao;Huang, Chang-Wei;Chen, Chuin-Shan
    • Interaction and multiscale mechanics
    • /
    • 제7권1호
    • /
    • pp.543-561
    • /
    • 2014
  • We present a full energy and force formulation of the quasicontinuum method with non-local and local transition elements. Non-local transition elements are developed to transmit inhomogeneity from the atomistic to the continuum regions. Local transition elements are developed to resolve the mathematical mismatch between non-local atoms and the local continuum. The rationale behind these transition elements is provided by analyzing the energy and force transitions between atoms and continuum under the Cauchy-Born rule. We show that breakdown of the Cauchy-Born rule occurs for slaved atoms of local elements within the cutoff of non-local atoms. The inadequacy of the Cauchy-Born rule at the transition region naturally leads to the need of atomistic treatment of transition slaved and transition representative atoms. Such an atomistic treatment together with a full or cutoff sampling allows non-local transition elements containing these transition entities to transmit inhomogeneity. Different force formulations for transition representative atoms and pure local representative atoms allow the local transition elements to resolve non-local and local mismatches. The method presented herein is validated by force calculations in an unstressed perfect crystal as well as an unrelaxed grain boundary model. A nanoindentation simulation in 3D is conducted to demonstrate the accuracy and efficiency of the proposed method.

개미군락시스템에서 수정된 지역 갱신 규칙을 이용한 최적해 탐색 기법 (Optimal solution search method by using modified local updating rule in Ant Colony System)

  • 홍석미;정태충
    • 한국지능시스템학회논문지
    • /
    • 제14권1호
    • /
    • pp.15-19
    • /
    • 2004
  • 개미군락시스템 (Ant Colony System, ACS)은 조합 최적화 문제를 해결하기 위한 기법으로 생물학적 기반의 메타휴리스틱 접근법이다. 지나간 경로에 대하여 페로몬을 분비하고 통신 매개물로 사용하는 실제 개미들의 추적 행위를 기반으로 한다. 최적 경로를 찾기 위해서는 보다 다양한 에지들에 대한 탐색이 필요하다. 기존 개미군락시스템의 지역 갱신 규칙에서는 지나간 에지에 대하여 고정된 페로몬 갱신 값을 부여하고 있다. 그러나 본 논문에서는 방문한 도시간의 거리와 해당 에지의 방문 횟수를 이용하여 페로몬을 부여한다. 보다 많은 정보를 탐색에 활용함으로써 기존의 방법에 비해 지역 최적화에 빠지지 않고 더 나은 해를 찾을 수 있었다.

학습된 지식의 분석을 통한 신경망 재구성 방법 (Restructuring a Feed-forward Neural Network Using Hidden Knowledge Analysis)

  • 김현철
    • 한국정보과학회논문지:소프트웨어및응용
    • /
    • 제29권5호
    • /
    • pp.289-294
    • /
    • 2002
  • 다층신경회로망 구조의 재구성은 회로망의 일반화 능력이나 효율성의 관점에서 중요한 문제로 연구되어왔다. 본 논문에서는 신경회로망에 학습된 은닉 지식들을 추출하여 조합함으로써 신경회로망의 구조를 재구성하는 새로운 방법을 제안한다. 먼저, 각 노드별로 학습된 대표적인 지역 규칙을 추출하여 각 노드의 불필요한 연결구조들을 제거한 후, 이들의 논리적인 조합을 통하여 중복 또는 상충되는 노드와 연결구조를 제거한다. 이렇게 학습된 지식을 분석하여 노드와 연결구조를 재구성한 신경회로망은 처음의 신경회로망에 비하여 월등히 감소된 구조 복잡도를 가지며 일반적으로 더 우수한 일반화 능력을 가지게 됨을 실험결과로서 제시하였다.

복잡계의 세포자동화법을 이용한 뼈의 적응적 재구축에 관한 연구 (A Study of Adaptive Bone Remodeling by Cellular Automata Method)

  • 문병영;박정홍;손권
    • 대한기계학회논문집A
    • /
    • 제27권7호
    • /
    • pp.1103-1109
    • /
    • 2003
  • An adaptive bone remodeling is simulated by using the cellular automata (CA) method. It is assumed that bone tissue consist of bone marrow, osteoclast, osteoblast cell or osteoprogenitor cell. Two types of local rule are adopted; those are the metabolism rule and adaptive bone formation rule. The metabolism rule is based on the interactions of cells and the bone formation rule is based on the adaptation against the mechanical stimulus. The history of load and memory of mechanical stimulus are also considered in the local rules. As a result, the pattern of distribution of the bone tissue is dynamically adequate and it is similar to intact cancellous bone.

규칙에 기초한 마스크 레이아웃 변환 시스템의 설계 및 구현 (Design and Implementation of Rule-based Mask Layout Transformation System)

  • 이재황;전주식
    • 전자공학회논문지A
    • /
    • 제30A권9호
    • /
    • pp.46-58
    • /
    • 1993
  • Owing to the nature of locality in mask layouts, it appears that most mask layout problems can be solved by transforming a part of the given mask layout into a better layout segment continuously toward a global suboptimal solution. This notion of local transformation addresses major weak points of existing mask layout processing systems, which lack both extensibility and unifiability. This paper attempts to elaborate upon developing a new rule-based mask layout transformation system wherein most of the mask layout problems can be solved under the unified framework of local mask layout transformation. The rule-based mask layout transformation system is applicable to various mask layout problems such as net extraction, mask layout compaction, mask layout editing, and design rule checking. The experimental results show that the rule-based expert system approach is an efficient means of solving those mask layout problems, and thus confronting major drawbacks of existing layout processing systems.

  • PDF