• Title/Summary/Keyword: Scale complexity

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[ $H_{\infty}$ ] Control for a Class of Singularly Perturbed Nonlinear Systems via Successive Galerkin Approximation

  • Kim, Young-Joong;Lim, Myo-Taeg
    • International Journal of Control, Automation, and Systems
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    • v.5 no.5
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    • pp.501-507
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    • 2007
  • This paper presents a new algorithm for the closed-loop $H_{\infty}$ control of a class of singularly perturbed nonlinear systems with an exogenous disturbance, using the successive Galerkin approximation (SGA). The singularly perturbed nonlinear system is decomposed into two subsystems of a slow-time scale and a fast-time scale in the spirit of the general theory of singular perturbation. Two $H_{\infty}$ control laws are obtained to each subsystem by using the SGA method. The composite control law that consists of two $H_{\infty}$ control laws of each subsystem is designed. One of the purposes of this paper is to design the closed-loop $H_{\infty}$ composite control law for the singularly perturbed nonlinear systems via the SGA method. The other is to reduce the computational complexity when the SGA method is applied to the high order systems.

Inferences Frequently Used in Earth Science

  • Kim, Chan-Jong
    • Journal of the Korean earth science society
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    • v.23 no.2
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    • pp.188-193
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    • 2002
  • Various research methods have been used in science depending on the various contexts. This implies that certain methods or inferences may be more frequently used in earth science. The purpose of the study are to explore the contexts of earth science, and the inferences frequently used in earth science. The context earth science research is quite different from that of other areas of natural science in terms of its time scale, space scale, accessibility, complexity, and controllability. The purpose of earth science research is twofold: historical and causal. The inferences frequently used in earth science are abduction and prediction. Abductive inferences go from the resulting state to controlling state. Predictive inferences go from hypothesis to expected data.

A Study on Scale-Invariant Features Extraction and Distance Measurement for Localization of Mobile Robot (이동로봇의 위치 추정을 위한 스케일 불변 특징점 추출 및 거리 측정에 관한 연구)

  • Jung, Dae-Seop;Jang, Mun-Suk;Ryu, Je-Goon;Lee, Eung-Hyuk;Shim, Jae-Hong
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.625-627
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    • 2005
  • Existent distance measurement that use camera is method that use both Stereo Camera and Monocular Camera, There is shortcoming that method that use Stereo Camera is sensitive in effect of a lot of expenses and environment variables, and method that use Monocular Camera are big computational complexity and error. In this study, reduce expense and error using Monocular Camera and I suggest algorithm that measure distance, Extract features using scale Invariant features Transform(SIFT) for distance measurement, and this measures distance through features matching and geometrical analysis, Proposed method proves measuring distance with wall by geometrical analysis free wall through feature point abstraction and matching.

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METALLIC INTERFACES IN HARSH CHEMO-MECHANICAL ENVIRONMENTS

  • Yildiz, Bilge;Nikiforova, Anna;Yip, Sidney
    • Nuclear Engineering and Technology
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    • v.41 no.1
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    • pp.21-38
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    • 2009
  • The use of multi scale modeling concepts and simulation techniques to study the destabilization of an ultrathin layer of oxide interface between a metal substrate and the surrounding environment is considered. Of particular interest are chemo-mechanical behavior of this interface in the context of a molecular-level description of stress corrosion cracking. Motivated by our previous molecular dynamics simulations of unit processes in materials strength and toughness, we examine the challenges of dealing with chemical reactivity on an equal footing with mechanical deformation, (a) understanding electron transfer processes using first-principles methods, (b) modeling cation transport and associated charged defect migration kinetics, and (c) simulation of pit nucleation and intergranular deformation to initiate the breakdown of the oxide interlayer. These problems illustrate a level of multi-scale complexity that would be practically impossible to attack by other means; they also point to a perspective framework that could guide future research in the broad computational science community.

Required Video Analytics and Event Processing Scenario at Large Scale Urban Transit Surveillance System (도시철도 종합감시시스템에서 요구되는 객체인식 기능 및 시나리오)

  • Park, Kwang-Young;Park, Goo-Man
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.3
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    • pp.63-69
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    • 2012
  • In this paper, we introduced design of intelligent surveillance camera system and typical event processing scenario for urban transit. To analyze video, we studied events that frequently occur in surveillance camera system. Event processing scenario is designed for seven representative situations(designated area intrusion, object abandon, object removal in designated area, object tracking, loitering and congestion measurement) in urban transit. Our system is optimized for low hardware complexity, real time processing and scenario dependent solution.

Research on a Streamlined Software Project Management Model for Small-sized Software Enterprises (소규모 소프트웨어 업체를 위한 간략화 된 프로젝트 관리 모델에 관한 연구)

  • Lee, Jeong-Eun;Park, Ju-Chull
    • IE interfaces
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    • v.21 no.2
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    • pp.198-208
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    • 2008
  • Effective management of a project is a crucial issue to software companies. There are various international standards, such as CMM, ISO9000, and SPICE, applied to project management. But, small scale companies have some difficulties in accepting those standards because of its complexity and enormous manpower requirements. This study proposes a project management approach streamlining the CMM by which a small scale software company can perform the tasks with ease. A prototype system has also been developed to show the capability of the proposed model.

An Exploratory Study on Common Information System Implementation Efficiency Among Overseas Subsidiaries of a Multinational Corporation (다국적 기업의 해외 자회사간 공용 정보시스템 구현 효율성에 관한 탐색적 연구)

  • Kim, Do-Yeong;Kim, Young-Gul;Lee, Gil-Hyung
    • Asia pacific journal of information systems
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    • v.9 no.2
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    • pp.117-132
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    • 1999
  • Common system deployment is one of the global information systems strategies of a multinational corporation for large-scale development that can provide economies of scale and optimal use of scarce technical expertise. But while the same (headquarter) team implements the same system, the resulting efficiencies of those projects differ widely among the subsidiaries. This paper focuses on the differences between the efficiencies of these implementation projects. Eight prepropositions about the factors causing the differences have been developed from the previous research. These prepropositions are explored through a case study on the twelve overseas subsidiaries of a multinational electronic corporation headquartered in Korea. We found that three factors(autonomy of subsidiary, complexity of task, experience level of users) have strong relevant relationships and two factors(level of subsidiary country, level of process formality) have partial relevant relationships with the implementation outcome.

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WLSD: A Perceptual Stimulus Model Based Shape Descriptor

  • Li, Jiatong;Zhao, Baojun;Tang, Linbo;Deng, Chenwei;Han, Lu;Wu, Jinghui
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.12
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    • pp.4513-4532
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    • 2014
  • Motivated by the Weber's Law, this paper proposes an efficient and robust shape descriptor based on the perceptual stimulus model, called Weber's Law Shape Descriptor (WLSD). It is based on the theory that human perception of a pattern depends not only on the change of stimulus intensity, but also on the original stimulus intensity. Invariant to scale and rotation is the intrinsic properties of WLSD. As a global shape descriptor, WLSD has far lower computation complexity while is as discriminative as state-of-art shape descriptors. Experimental results demonstrate the strong capability of the proposed method in handling shape retrieval.

Clustering Algorithm of Hierarchical Structures in Large-Scale Wireless Sensor and Actuator Networks

  • Quang, Pham Tran Anh;Kim, Dong-Seong
    • Journal of Communications and Networks
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    • v.17 no.5
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    • pp.473-481
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    • 2015
  • In this study, we propose a clustering algorithm to enhance the performance of wireless sensor and actuator networks (WSANs). In each cluster, a multi-level hierarchical structure can be applied to reduce energy consumption. In addition to the cluster head, some nodes can be selected as intermediate nodes (INs). Each IN manages a subcluster that includes its neighbors. INs aggregate data from members in its subcluster, then send them to the cluster head. The selection of intermediate nodes aiming to optimize energy consumption can be considered high computational complexity mixed-integer linear programming. Therefore, a heuristic lowest energy path searching algorithm is proposed to reduce computational time. Moreover, a channel assignment scheme for subclusters is proposed to minimize interference between neighboring subclusters, thereby increasing aggregated throughput. Simulation results confirm that the proposed scheme can prolong network lifetime in WSANs.

Design of Morphological Filter for Image Processing (영상처리용 Morphological Filter의 하드웨어 설계)

  • 문성용;김종교
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.10
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    • pp.1109-1116
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    • 1992
  • Mathematical morphology, theoretical foundation for morphological filter, is very efficient for the analysis of the geometrical characteristics of signals and systems and is used as a predominant tool for smoothing the data with noise. In this study, H/W design of morphological filter is implemented to process the gray scale dilation and the erosion in the same circuit and to choose the maximum and minimum value by a selector, resulting in their education of the complexity of the circuit and an architecture for parallel processing. The structure of morphological filter consists of the structuring-element block, the image data block, the control block, the ADD block, the MIN/MAX block, etc, and is designed on an one-chip for real time operation.

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