• Title/Summary/Keyword: hierarchical control

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A New Approach for Hierarchical Optimization of Large Scale Non-linear Systems (대규모 비선형 시스템의 새로운 계층별 최적제어)

  • Park, Joon-Hoon;Kim, Jong-Boo
    • Journal of the Korean Institute of Telematics and Electronics T
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    • v.36T no.2
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    • pp.21-31
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    • 1999
  • This paper presents a new possibility of calculating optimal control for large scale which consist of non-linear dynamic sub-systems using two level hierarchical structures method. And the proposed method is based on the idea of block pulse transformation to simplify the algorithm and its calculation. This algorithm used an expansion around the equilibrium point of the system to fix the second and higher order terms. These terms are compensated for iteratively at the second level by providing a prediction for the states and controls which form of a part of the higher order terms. In this new approach the quadratic penalty terms are not used in the cost function. This allows convergence over a longer time horizon and also provides faster convergence. And the method is applied to the problem of optimization of the synchronous machine. Results show that the new approach is superior to conventional numerical method or other previous algorithm.

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The Effects of Personality Variables and Values on Pro-environmental Product Purchase and Recycling Behaviors

  • Koo, Dong-Mo
    • Journal of Global Scholars of Marketing Science
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    • v.5
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    • pp.171-204
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    • 2000
  • This paper intends to investigate the hierarchical effects of personality variables and values on pro-environmental product purchase and recycling behaviors mediated by 3 factor environmental attitudes. Previous literature review on pro-environmental behaviors has three categories of research trends. The first category generally done during 70's and early 80's is mainly focused on identifying pro-environmental consumer groups. Second stream of studies has focused on the mediating and moderating effects of variables, such as PCE, environmental knowledge, the perceived importance of behavioral consequences etc., on various pro-environmental behaviors. The last and latest trends of literature is focused on hierarchical and interactive effects of variables on behaviors. Following the trends of literature is review of such specific variables as social responsibility, community mindedness, locus of control, values, and environmental attitudes. The result shows that both locus of control and social responsibility have positive effects on two of environmental attitudes, harmony with nature and limits to growth, but community mindedness did not have effects on environmental attitudes. And social belonging value has positive effects on two of environmental attitudes, limits to growth and nature over human, and environmental value has positive effects on the formation of harmony with nature and limits to growth. But self-actualization has negative effects. And it's also suggested the positive effects of environmental attitudes on purchase and recycling behaviors. Specifically, all environmental attitude variables have positive effects on the formation of pro-environmental product purchase and recycling behaviors except in case of the effects of nature over human to recycling. And it's also revealed that pro-environmental product purchase is a preceeding behavior to recycling behavior, which suggest that consumers have to purchase environment friendly and recyclable products in order to engage in effective recycling behavior. Various applications of the results are discussed in the conclusion.

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On Constructing NURBS Surface Model from Scattered and Unorganized 3-D Range Data (정렬되지 않은 3차원 거리 데이터로부터의 NURBS 곡면 모델 생성 기법)

  • Park, In-Kyu;Yun, Il-Dong;Lee, Sang-Uk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.37 no.3
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    • pp.17-30
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    • 2000
  • In this paper, we propose an efficient algorithm to produce 3-D surface model from a set of range data, based on NURBS (Non-Uniform Rational B-Splines) surface fitting technique. It is assumed that the range data is initially unorganized and scattered 3-D points, while their connectivity is also unknown. The proposed algorithm consists of three steps: initial model approximation, hierarchical representation, and construction of the NURBS patch network. The mitral model is approximated by polyhedral and triangular model using K-means clustering technique Then, the initial model is represented by hierarchically decomposed tree structure. Based on this, $G^1$ continuous NURBS patch network is constructed efficiently. The computational complexity as well as the modeling error is much reduced by means of hierarchical decomposition and precise approximation of the NURBS control mesh Experimental results show that the initial model as well as the NURBS patch network are constructed automatically, while the modeling error is observed to be negligible.

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Design of Optimized Fuzzy Cascade Controller Based on HFCGA for Ball & Beam System (볼빔 시스템에 대한 계층적 공정 경쟁 유전자 알고리즘을 이용한 최적 퍼지 Cascade 제어기 설계)

  • Jang, Han-Jong;Oh, Sung-Kwun;Kim, Hyun-Ki
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.2
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    • pp.391-398
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    • 2009
  • In this study, we introduce the design methodology of an optimized fuzzy cascade controller with the aid of hierarchical fair competition-based genetic algorithm(HFCGA) for ball & beam system. The ball & beam system consists of servo motor, beam and ball, and remains mutually connected in line in itself. The ball & beam system determines the position of ball through the control of a servo motor. The displacement change the position of ball leads to the change of the angle of the beam which determines the position angle of a servo motor. Consequently the displacement change of the position of the moving ball and its ensuing change of the angle of the beam results in the change of the position angle of a servo motor. We introduce the fuzzy cascade controller scheme which consists of the outer(1st) controller and the inner(2nd) controller as two cascaded fuzzy controllers, and auto-tune the control parameters(scaling factors) of each fuzzy controller using HFCGA. The inner controller controls the position of lever arm which corresponds to the position angle of a servo motor and the outer controller decides the set-point value of the inner controller. HFCGA is a kind of parallel genetic algorithms(PGAs), and helps alleviate the premature convergence being generated in conventional genetic algorithms (GAs). For a detailed comparative analysis from the viewpoint of the performance results and the design methodology, the proposed method for the ball & beam system which is realized by the fuzzy cascade controller based on HFCGA, is presented in comparison with the conventional PD cascade controller based on serial genetic algorithms.

Hierarchical Power Management Architecture and Optimal Local Control Policy for Energy Efficient Networks

  • Wei, Yifei;Wang, Xiaojun;Fialho, Leonardo;Bruschi, Roberto;Ormond, Olga;Collier, Martin
    • Journal of Communications and Networks
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    • v.18 no.4
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    • pp.540-550
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    • 2016
  • Since energy efficiency has become a significant concern for network infrastructure, next-generation network devices are expected to have embedded advanced power management capabilities. However, how to effectively exploit the green capabilities is still a big challenge, especially given the high heterogeneity of devices and their internal architectures. In this paper, we introduce a hierarchical power management architecture (HPMA) which represents physical components whose power can be monitored and controlled at various levels of a device as entities. We use energy aware state (EAS) as the power management setting mode of each device entity. The power policy controller is capable of getting information on how many EASes of the entity are manageable inside a device, and setting a certain EAS configuration for the entity. We propose the optimal local control policy which aims to minimize the router power consumption while meeting the performance constraints. A first-order Markov chain is used to model the statistical features of the network traffic load. The dynamic EAS configuration problem is formulated as a Markov decision process and solved using a dynamic programming algorithm. In addition, we demonstrate a reference implementation of the HPMA and EAS concept in a NetFPGA frequency scaled router which has the ability of toggling among five operating frequency options and/or turning off unused Ethernet ports.

Factors Affecting Health Promotion Behavior among Workers with High Risk of Metabolic Syndrome: Based on Theory of Planned Behavior (대사증후군 고위험 근로자의 건강증진 행위에 미치는 영향 요인: 계획적 행위 이론 적용)

  • Park, Sungwon;Yang, Sook Ja
    • Research in Community and Public Health Nursing
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    • v.26 no.2
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    • pp.128-139
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    • 2015
  • Purpose: The purpose of this study was to identify factors affecting health promotion behavior among workers with high risk of metabolic syndrome. This study was based on the planned behavior theory. Methods: The participants were 167 workers at high risk of metabolic syndrome. Data were collected using a structured questionnaire. Surveyed variables were attitude, subjective norm, perceived behavioral control, intention, and health promotion behavior. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and hierarchical regression analysis with SPSS/WIN 22.0. Results: Perceived behavioral control affected the intention of health promotion behavior among the workers with high risk of metabolic syndrome. It explained 62% of variance in the intention of health promotion behavior (F=40.09, p<.001). Perceived behavioral control and occupation affected health promotion behavior among the risk workers with high risk of metabolic syndrome. The two factors explained 16% of variance in health promotion behavior (F=4.95, p<.001). Conclusion: The findings of this study suggest that perceived behavioral control is the only factor affecting health promotion behavior when the theory of planned behavior was applied. Therefore, intervention programs for improving health promotion behavior should be focused on strengthening perceived behavioral control.

An Efficient Router Assistance Mechanism for Reliable Multicast (신뢰성 보장을 위한 멀티캐스트에서의 효율적인 라우터 지원)

  • 최종원;최인영
    • Journal of KIISE:Information Networking
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    • v.31 no.2
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    • pp.224-232
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    • 2004
  • To guarantee the reliability in multicast transmission, researches providing reliability through hierarchical control tree which is independent on data channel tree are known to provide high scalability. However, the logical control tree in transport layer constructed without topology information of the corresponding network layer tree may inefficiently use the network resources because the logical control tree is not closely related to the tree topology of the network layer. A router assisted control tree mechanism presented in this paper would improve the efficiency of the link as well as it would remove the replicated data. In addition, it requires to a router a small change which examines the message type of the control tree.

Development and Verification of Zigbee-Based Monitoring and Control System for Electric Heat Tracing (Electric Heat Tracing을 위한 Zigbee 기반 통합 감시제어 시스템의 개발 및 검증)

  • Park, Sung-Woo;Park, Sun-Eng
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.12
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    • pp.1395-1402
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    • 2015
  • An electric heat tracing system manages the temperature of pipes used in a plant. We propose a Zigbee-based wireless system so called the TESCON(: TEmperature Sensing and CONtrol) to monitor and control the electric heat tracing system in an integrated way. Simulations have been done to analyze the performance of the TESCON system. The performance of the TESCON system is validated by obtaining similar results via testbed operation. We also suggest an extension method of the TESCON system based on the hierarchical tree topology by adopting techniques such as network partition, channel reuse and frame aggregation.

The Effects of Self-Acceptance, Social Support and Internal Locus of Control on Speech Anxiety in Elementary School Students (초등학생의 자기수용, 사회적 지지, 내적통제성이 발표불안에 미치는 영향)

  • Kim, Yun-Jeon;Park, Boo-Jin
    • Journal of Families and Better Life
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    • v.30 no.1
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    • pp.41-53
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    • 2012
  • The purpose of this study was to determine how elementary school students' self-acceptance, social support and internal locus of control affect their speech anxiety. A questionnaire survey was distributed to 570 fifth and sixth graders attending 4 elementary schools located in Seoul. A total of 534 surveys were completed and were analyzed with SPSS WIN 12.0 including frequency test, t-test, Pearson's correlations analysis, simultaneous multiple regression and hierarchical multiple regression analysis. The findings of this study are summarized as follows. First, among self-acceptance, social support, internal locus of control and speech anxiety, gender affected speech anxiety. Second, speech anxiety was most affected by self-acceptance, followed by social support, internal locus of control and gender in the order of mention. Third, social support had moderating effects on the relationship between self-acceptance and speech anxiety.

An Analytical Evaluation of 2D Mesh-connected SIMD Architecture for Parallel Matrix Multiplication (2D Mesh SIMD 구조에서의 병렬 행렬 곱셈의 수치적 성능 분석)

  • Kim, Cheong-Ghil
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.10 no.1
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    • pp.7-13
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    • 2011
  • Matrix multiplication is a fundamental operation of linear algebra and arises in many areas of science and engineering. This paper introduces an efficient parallel matrix multiplication scheme on N ${\times}$ N mesh-connected SIMD array processor, called multiple hierarchical SIMD architecture (HMSA). The architectural characteristic of HMSA is the hierarchically structured control units which consist of a global control unit, N local control units configured diagonally, and $N^2$ processing elements (PEs) arranged in an N ${\times}$ N array. PEs are communicating through local buses connecting four adjacent neighbor PEs in mesh-torus networks and global buses running across the rows and columns called horizontal buses and vertical buses, respectively. This architecture enables HMSA to have the features of diagonally indexed concurrent broadcast and the accessibility to either rows (row control mode) or columns (column control mode) of 2D array PEs alternately. An algorithmic mapping method is used for performance evaluation by mapping matrix multiplication on the proposed architecture. The asymptotic time complexities of them are evaluated and the result shows that paralle matrix multiplication on HMSA can provide significant performance improvement.

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