• 제목/요약/키워드: Multiple system

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ART2 신경회로망을 이용한 선형 시스템의 다중고장진단 (Multiple faults diagnosis of a linear system using ART2 neural networks)

  • 이인수;신필재;전기준
    • 제어로봇시스템학회논문지
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    • 제3권3호
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    • pp.244-251
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    • 1997
  • In this paper, we propose a fault diagnosis algorithm to detect and isolate multiple faults in a system. The proposed fault diagnosis algorithm is based on a multiple fault classifier which consists of two ART2 NN(adaptive resonance theory2 neural network) modules and the algorithm is composed of three main parts - parameter estimation, fault detection and isolation. When a change in the system occurs, estimated parameters go through a transition zone in which residuals between the system output and the estimated output cross the threshold, and in this zone, estimated parameters are transferred to the multiple faults classifier for fault isolation. From the computer simulation results, it is verified that when the proposed diagnosis algorithm is performed successfully, it detects and isolates faults in the position control system of a DC motor.

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OFDM 기반 다중 안테나 시스템의 링크레벨 성능검증 - MIMO OFDM vs. Smart Antenna OFDM (Link-level Performance Verification of the Multiple Antenna Systems - MIMO OFDM vs. Smart Antenna OFDM)

  • 박성호;김규현;허주;장경희
    • 한국통신학회논문지
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    • 제31권6A호
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    • pp.563-574
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    • 2006
  • 본 논문에서는 OFDM(Orthogonal Frequency Division Multiplexing) 기반 다중 안테나 시스템의 링크레벨 성능 분석을 위하여 실제 전파 환경과 유사한 특성을 갖는 Ray-tracing 방식 채널의 하나인 SCM(Spatial Channel Model) 채널을 구현한다. 3GPP & 3GPP2 Spatial Channel AHG(Ad-hoc Group)에서 시스템레벨 성능 비교용으로 제안한 SCM 채널을 링크레벨 성능의 비교 분석을 위하여, 본 논문에서는 시스템레벨 채널에 대한 채널 계수 및 파라메터들을 링크레벨 성능 비교용으로 변환하여 구현한다. 모의실험을 통하여 구현한 SCM 채널의 특성을 검증하고, 이를 이용하여 기존의 OFDM 기반 MIMO (Multiple Input Multiple Output) 적용 시스템 및 스마트 안테나 적용 시스템에서의 실제적인 링크레벨 성능을 분석하고, 정확한 비교 검증을 위하여 SCM 채널과 동일한 파라메터를 적용한 I-METRA 채널 및 독립 채널 상황에서의 링크 레벨 성능을 함께 비교 분석한다. MIMO 및 스마트 안테나 적용 시스템에 대하여 여러 채널 환경에서 채널 상관도에 따른 링크레벨 성능을 분석함으로써, 채널 상관도의 영향에 따라 주어진 환경에 적합한 다중 안테나 시스템을 제안한다.

보행장애를 주소로 하는 소뇌형 다계통 위축증 환자의 한방 치료 1례 (A Case Report of Multiple System Atrophy in a Cerebellar Ataxia Patient Suffering from Gait Disturbance Treated with Korean Medicine)

  • 우성진;백경민;장우석
    • 대한한방내과학회지
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    • 제37권5호
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    • pp.806-814
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    • 2016
  • Objective: To describe the effect of Korean medicine on gait disturbance in a patient with multiple system atrophy and cerebellar ataxia. Methods: We observed a 75-year-old female patient who had multiple system atrophy and cerebellar ataxia. The patient was treated with Korean medicine, including acupuncture, moxibustion, and herbal medicine (Yukmijihwang-tang-gamibang and Boyanghwano-tang-gamibang) for 38 days. We evaluated the patient with the Korean version of the Berg Balance Scale (K-BBS), the Unified Multiple System Atrophy Rating Scale (UMSARS), and the Numeric Rating Scale-11 (NRS-11). Results: After treatment, the patient’s symptoms were improved. The K-BBS score increased from 9 to 19, while the UMSARS score decreased from 16 to 12 in Part I, from 15 to 7 in part Ⅱ, and from 4 to 3 in part Ⅳ. The NRS-11 score of gait disturbance decreased from 10 to 5. Conclusions: Korean medicine may be an effective treatment for gait disturbance in multiple system atrophy with cerebellar ataxia.

Maximum Ratio Transmission for Space-Polarization Division Multiple Access in Dual-Polarized MIMO System

  • Hong, Jun-Ki;Jo, Han-Shin;Mun, Cheol;Yook, Jong-Gwan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권8호
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    • pp.3054-3067
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    • 2015
  • The phenomena of higher channel cross polarization discrimination (XPD) is mainly observed for future wireless technologies such as small cell network and massive multiple-input multiple-output (MIMO) system. Therefore, utilization of high XPD is very important and space-polarization division multiple access (SPDMA) with dual-polarized MIMO system could be a suitable solution to high-speed transmission in high XPD environment as well as reduction of array size at base station (BS). By SPDMA with dual-polarized MIMO system, two parallel data signals can be transmitted by both vertically and horizontally polarized antennas to serve different mobile stations (MSs) simultaneously compare to conventional space division multiple access (SDMA) with single-polarized MIMO system. This paper analyzes the performance of SPDMA for maximum ratio transmission (MRT) in time division duplexing (TDD) system by proposed dual-polarized MIMO spatial channel model (SCM) compare to conventional SDMA. Simulation results indicate that how SPDMA utilizes the high XPD as the number of MS increases and SPDMA performs very close to conventional SDMA for same number of antenna elements but half size of the array at BS.

A Multiple-Valued Fuzzy Approximate Analogical-Reasoning System

  • Turksen, I.B.;Guo, L.Z.;Smith, K.C.
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.1274-1276
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    • 1993
  • We have designed a multiple-valued fuzzy Approximate Analogical-Reseaning system (AARS). The system uses a similarity measure of fuzzy sets and a threshold of similarity ST to determine whether a rule should be fired, with a Modification Function inferred from the Similarity Measure to deduce a consequent. Multiple-valued basic fuzzy blocks are used to construct the system. A description of the system is presented to illustrate the operation of the schema. The results of simulations show that the system can perform about 3.5 x 106 inferences per second. Finally, we compare the system with Yamakawa's chip which is based on the Compositional Rule of Inference (CRI) with Mamdani's implication.

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Multiple crack evaluation on concrete using a line laser thermography scanning system

  • Jang, Keunyoung;An, Yun-Kyu
    • Smart Structures and Systems
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    • 제22권2호
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    • pp.201-207
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    • 2018
  • This paper proposes a line laser thermography scanning (LLTS) system for multiple crack evaluation on a concrete structure, as the core technology for unmanned aerial vehicle-mounted crack inspection. The LLTS system consists of a line shape continuous-wave laser source, an infrared (IR) camera, a control computer and a scanning jig. The line laser generates thermal waves on a target concrete structure, and the IR camera simultaneously measures the corresponding thermal responses. By spatially scanning the LLTS system along a target concrete structure, multiple cracks even in a large scale concrete structure can be effectively visualized and evaluated. Since raw IR data obtained by scanning the LLTS system, however, includes timely- and spatially-varying IR images due to the limited field of view (FOV) of the LLTS system, a novel time-spatial-integrated (TSI) coordinate transform algorithm is developed for precise crack evaluation in a static condition. The proposed system has the following technical advantages: (1) the thermal wave propagation is effectively induced on a concrete structure with low thermal conductivity of approximately 0.8 W/m K; (2) the limited FOV issues can be solved by the TSI coordinate transform; and (3) multiple cracks are able to be visualized and evaluated by normalizing the responses based on phase mapping and spatial derivative processes. The proposed LLTS system is experimentally validated using a concrete specimen with various cracks. The experimental results reveal that the LLTS system successfully visualizes and evaluates multiple cracks without false alarms.

Design and Implementation of a SDR-based Digital Filter for CDMA Systems

  • Yu, Bong-Guk;Bang, Young-Jo;Kim, Dae-Ho;Lee, Kyu-Tae;Ra, Sung-Woong
    • Journal of Ubiquitous Convergence Technology
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    • 제2권2호
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    • pp.59-66
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    • 2008
  • In this study, Software Defined Radio (SDR) technology-based digital filterbank architecture applicable to a multiple-channel processing system such as a wireless mobile communication system using Code Division Multiple Access (CDMA) technology is proposed. The technique includes a micro-processor to redesign Finite Impulse Response (FIR) filter coefficients according to specific system information and to download the filter coefficients to one digital Band Pass Filter (BPF) to reconfigure another system. The feasibility of the algorithm is verified by computer simulation and by implementing a multiple-channel signal generator that is reconfigurable to other system profiles, including those of a Wideband Code Division Multiple Access (WCDMA) system and a CDMA system.

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Reliability analysis of an embedded system with multiple vacations and standby

  • Sharma, Richa;Kaushik, Manju;Kumar, Gireesh
    • International Journal of Reliability and Applications
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    • 제16권1호
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    • pp.35-53
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    • 2015
  • This investigation deals with reliability and sensitivity analysis of a repairable embedded system with standby wherein repairman takes multiple vacations. The hardware system consists of 'M' operating and 'S' standby components. The repairman can leave for multiple vacations of random length during its idle time. Whenever any operating unit fails, it is immediately replaced by a standby unit if available. Moreover, governing equations of an embedded system are constructed using appropriate birth-death rates. The vacation and repair time of repairman are exponentially distributed. The matrix method is used to find the steady-state probabilities of the number of failed components in the embedded system as well as other performance measures. Reliability indexes are presented. Further, numerical experiments are carried out for various system characteristics to examine the effects of different parameter. Using a special class of neuro-fuzzy systems i.e. Adaptive Network-based Fuzzy Interference Systems (ANFIS), we also approximate various performance measures. Finally, the conclusions and future research directions are provided.

X-Plane 및 MATLAB/Simulink 기반의 복수무인기 모의실험 시스템 개발 (Implementation of a X-Plane and MATLAB/Simulink based Simulation System for Multiple UAVs)

  • 문상우;오은미;유동일;심현철
    • 제어로봇시스템학회논문지
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    • 제19권5호
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    • pp.442-449
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    • 2013
  • In this paper, a simulation system based on X-Plane and MATLAB/Simulink for multiple UAVs is presented. For the conceptual design of this proposed system, a hierarchical system architecture for multiple UAVs is presented. This architecture has object-oriented data structure which consists of three objects (UAV status, mission and task, and environment) and a hierarchy consisting of four layers (decision making layer, task assignment layer, path and motion planning layer, and collision avoidance layer) is also proposed. In addition, this paper shows a implementation of simulation system based on the proposed system architecture using X-Plane and MATLAB/Simulink. The result of simulation from the developed system in this paper validate capability of application for multiple UAVs in real environment.

A New Approach for Multiple Object Tracking ? Discrete Event based Multiple Object Tracking (DEMOT)

  • Kim, Chi-Ho;You, Bum-Jae;Kim, Hag-Bae;Oh, Sang-Rok
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1134-1139
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    • 2003
  • Tracking is a fundamental technique which is able to be applied to gesture recognition, visual surveillance, tangible agent and so forth. Especially, multiple object tracking has been extensively studied in recent years in order to perform many and more complicated tasks. In this paper, we propose a new approach of multiple object tracking which is based on discrete event. We call this system the DEMOT (Discrete Event based Multiple Object Tracking). This approach is based on the fact that a multiple object tracking can have just four situations - initiation, continuation, termination, and overlapping. Here, initiation, continuation, termination, and overlapping constitute a primary event set and this is based on the change of the number of extracted objects between a previous frame and a current frame. This system reduces computational costs and holds down the identity of all targets. We make experiments for this system with respect to the number of targets, each event, and processing period. We describe experimental results that show the successful multiple object tracking by using our approach.

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