• 제목/요약/키워드: Cellular Automaton

검색결과 36건 처리시간 0.027초

원심주조를 이용한 2종 알루미늄의 접합에 대한 연구 (A Study on the Joining of Different Al Alloys by Centrifugal Casting)

  • 장영수;이문형;문준영;홍준표
    • 한국주조공학회지
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    • 제27권6호
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    • pp.237-242
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    • 2007
  • To improve the quality of the product and the cost efficiency, the joining of A356 alloy to an Al-18wt%Si alloys has been performed by centrifugal casting. The influence of the mold preheating temperature, the pouring temperature and the rotational velocity of the mold on the microstructures of the shell in the centrifugal casting was investigated using the experimental and simulation methods. In the present study, the cellular automaton (CA) technique and the finite volume method (FVM) were adopted to simulate the evolution of the macro structures and to calculate the temperature profiles, respectively. The evolution of the microstructures was also simulated using a modified cellular automaton (MCA) model. The optimal rotational speed of the mold for obtaining the sound shape of the shell was estimated experimentally to be over 1200 rpm. For the uniform microstructure, the outer shell needs to be cast with higher preheated mold temperature and lower pouring temperature, and the melt was poured at lower temperature in the inner shell. In order to obtain the sound shape of the joining, the different materials were poured simultaneously.

Cellular Automaton법을 이용한 주물의 응고조직 시뮬레이션에의 적용 (Application of Solifidification Grain Structure Simulation for the Casting by Cellular Automaton Method)

  • 조인성
    • 한국주조공학회지
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    • 제21권1호
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    • pp.41-47
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    • 2001
  • 본 연구에서는 FDM법과 CA법을 결합하여 주물의 응고조직성장 예측 프로그램을 개발하였다. 새로운 농도장 분포 알고리즘을 개발하고, 이 결과를 1차원 해석해와 비교하였으며, 이를 2차원 응고조직 및 농도계산에 적용하였다. 3차원 응고조직 예측 해석연구를 통하여 복잡한 형상의 주물에 적용 하였으며, turbine blade형상의 응고조직 시뮬레이션을 통하여 인출속도가 응고조직에 미치는 영향에 대하여 조사하였고, 원하는 주조조업변수를 본 시뮬레이션에 의하여 결정할 수 있으리라 생각된다.

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Using a Cellular Automaton to Extract Medical Information from Clinical Reports

  • Barigou, Fatiha;Atmani, Baghdad;Beldjilali, Bouziane
    • Journal of Information Processing Systems
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    • 제8권1호
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    • pp.67-84
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    • 2012
  • An important amount of clinical data concerning the medical history of a patient is in the form of clinical reports that are written by doctors. They describe patients, their pathologies, their personal and medical histories, findings made during interviews or during procedures, and so forth. They represent a source of precious information that can be used in several applications such as research information to diagnose new patients, epidemiological studies, decision support, statistical analysis, and data mining. But this information is difficult to access, as it is often in unstructured text form. To make access to patient data easy, our research aims to develop a system for extracting information from unstructured text. In a previous work, a rule-based approach is applied to a clinical reports corpus of infectious diseases to extract structured data in the form of named entities and properties. In this paper, we propose the use of a Boolean inference engine, which is based on a cellular automaton, to do extraction. Our motivation to adopt this Boolean modeling approach is twofold: first optimize storage, and second reduce the response time of the entities extraction.

ON GROUP ORDERS OF SOME CELLULAR AUTOMATA

  • Kim, Jae-Gyeom
    • Korean Journal of Mathematics
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    • 제18권4호
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    • pp.357-368
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    • 2010
  • In this note, we will characterize group orders of hybrid CA configured with rules 60 and 195 and that configured with rules 102 and 153.

생물막 성장에 대한 세균의 초기 분포영향을 나타내는 셀룰라오토마톤 모델 (Cellular Automaton Models Revealing Effects of Initial Bacterial Distribution on Biofilm Growth)

  • 이상희;최경희;전태수
    • 생태와환경
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    • 제37권3호통권108호
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    • pp.297-303
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    • 2004
  • 수서 생태계에서 생물막 성장을 고찰하기 위해 2차원 셀룰라오토마톤 (CA) 모델을 구현하였다. 영양물 농도와 연계하여 CA의 단순한 지역 규칙을 세균 개체군의 성장을 나타내는데 적용하였다. 초기 세균 분포는 낮은 영양물 농도에서 개체군 크기와 생물막 형태를 결정하는데 중요한 역할을 하였다. 집중분포에서는 균일분포나 마구잡이분포에 비해 개체군 크기가 느리게 증가하였다. 반면 공극률은 다른 초기 분포에 비해 균일분포에서 높게 나타나는 경향을 보였다.

Continuity of directional entropy for a class of $Z^2$-actions

  • Park, Kyewon-K.
    • 대한수학회지
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    • 제32권3호
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    • pp.573-582
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    • 1995
  • J.Milnor[Mi2] has introduced the notion of directional entropy in his study of Cellular Automata. Cellular Automaton map can be considered as a continuous map from a space $K^Z^n$ to itself which commute with the translation of the lattice $Z^n$. Since the space $K^Z^n$ is compact, map S is uniformly continuous. Hence S is a block map(a finite code)[He]. (S is said to have a finite memory.) In the case of n = 1, we have a shift map, T on $K^Z$, and a block map S and they together generate a $Z^2$ action.

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패턴 인식을 위한 진화 셀룰라 분류기 (Evolvable Cellular Classifiers for Pattern Recognition)

  • Ju, Jae-ho;Shin, Yoon-cheol;Hoon Kang
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2000년도 춘계학술대회 학술발표 논문집
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    • pp.236-240
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    • 2000
  • A cellular automaton is well-known for self-organizing and dynamic behaviors in the field of artificial life. This paper addresses a new neuronic architecture called an evolvable cellular classifier which evolves with the genetic rules (chromosomes) in the non-uniform cellular automata. An evolvable cellular classifier is primarily based on cellular programing, but its mechanism is simpler because it utilizes only mutations for the main genetic operators and resembles the Hopfield network. Therefore, the desirable hi t-patterns could be obtained through evolutionary processes for just one individual agent. As a result, an evolvable hardware is derived which is applicable to classification of bit-string information.

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Real-Time Stochastic Optimum Control of Traffic Signals

  • Lee, Hee-Hyol
    • Journal of information and communication convergence engineering
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    • 제11권1호
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    • pp.30-44
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    • 2013
  • Traffic congestion has become a serious problem with the recent exponential increase in the number of vehicles. In urban areas, almost all traffic congestion occurs at intersections. One of the ways to solve this problem is road expansion, but it is difficult to realize in urban areas because of the high cost and long construction period. In such cases, traffic signal control is a reasonable method for reducing traffic jams. In an actual situation, the traffic flow changes randomly and its randomness makes the control of traffic signals difficult. A prediction of traffic jams is, therefore, necessary and effective for reducing traffic jams. In addition, an autonomous distributed (stand-alone) point control of each traffic light individually is better than the wide and/or line control of traffic lights from the perspective of real-time control. This paper describes a stochastic optimum control of crossroads and multi-way traffic signals. First, a stochastic model of traffic flows and traffic jams is constructed by using a Bayesian network. Secondly, the probabilistic distributions of the traffic flows are estimated by using a cellular automaton, and then the probabilistic distributions of traffic jams are predicted. Thirdly, optimum traffic signals of crossroads and multi-way intersection are searched by using a modified particle swarm optimization algorithm to realize real-time traffic control. Finally, simulations are carried out to confirm the effectiveness of the real-time stochastic optimum control of traffic signals.

Inversion of Spread-Direction and Alternate Neighborhood System for Cellular Automata-Based Image Segmentation Framework

  • Lee, Kyungjae;Lee, Junhyeop;Hwang, Sangwon;Lee, Sangyoun
    • Journal of International Society for Simulation Surgery
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    • 제4권1호
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    • pp.21-23
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    • 2017
  • Purpose In this paper, we proposed alternate neighborhood system and reverse spread-direction approach for accurate and fast cellular automata-based image segmentation method. Materials and Methods On the basis of a simple but effective interactive image segmentation technique based on a cellular automaton, we propose an efficient algorithm by using Moore and designed neighborhood system alternately and reversing the direction of the reference pixels for spreading out to the surrounding pixels. Results In our experiments, the GrabCut database were used for evaluation. According to our experimental results, the proposed method allows cellular automata-based image segmentation method to faster while maintaining the segmentation quality. Conclusion Our results proved that proposed method improved accuracy and reduced computation time, and also could be applied to a large range of applications.