• Title/Summary/Keyword: system identification

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On parameter identification algorithm using VSS theory (가변구조이론에 의한 파라미터 identification 알고리즘)

  • 심귀보;한동균;전홍태
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.927-930
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    • 1992
  • VSS identification approach is based on following concept, i.e. while in sliding motion, the switching of control inputs refects system uncertainites. Therefore, if there exist some operations that make the information form the switiching control inputs be achievable, then the unknown parameters can be actually identification mechanisms which can fully make use of the available information. Two different types of VSS identifiers are taken into consideration. The first type uses adjustable model whose structure is similar to that of identified systems. From the viewpoint of contro, this type of VSS identifiers may be regraded as direct identifier vecause the identified system is handled as an open loop. On the other hand, if the identified system is controlable in the sense of VSS(sliding mode can be generated through chosing control inputs), the second type of VSS identifier, the indirect VSS identifier, can be constructed according to the linerized system strucutre while staying in sliding mode. Therefroe it can be applied to some nonlinear systems which are not linear in parametric space by general identification algorithms, whereas linear in parametric space when sliding mode is existed.

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GMM-Based Maghreb Dialect Identification System

  • Nour-Eddine, Lachachi;Abdelkader, Adla
    • Journal of Information Processing Systems
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    • v.11 no.1
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    • pp.22-38
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    • 2015
  • While Modern Standard Arabic is the formal spoken and written language of the Arab world; dialects are the major communication mode for everyday life. Therefore, identifying a speaker's dialect is critical in the Arabic-speaking world for speech processing tasks, such as automatic speech recognition or identification. In this paper, we examine two approaches that reduce the Universal Background Model (UBM) in the automatic dialect identification system across the five following Arabic Maghreb dialects: Moroccan, Tunisian, and 3 dialects of the western (Oranian), central (Algiersian), and eastern (Constantinian) regions of Algeria. We applied our approaches to the Maghreb dialect detection domain that contains a collection of 10-second utterances and we compared the performance precision gained against the dialect samples from a baseline GMM-UBM system and the ones from our own improved GMM-UBM system that uses a Reduced UBM algorithm. Our experiments show that our approaches significantly improve identification performance over purely acoustic features with an identification rate of 80.49%.

A need-awaring multi-agent approach to nomadic community computing for ad hoc need identification and group formation

  • Choi, Keun-Ho;Kwon, Oh-Byung
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2005.11a
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    • pp.183-192
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    • 2005
  • Recently, community computing has been proposed for group formation and group decision-making. However, legacy community computing systems do not support group need identification for ad hoc group formation, which would be one of key features of ubiquitous decision support systems and services. Hence, this paper aims to provide a multi-agent based methodology to enable nomadic community computing which supports ad hoc need identification and group formation. Focusing on supporting group decision-making of relatively small sized multiple individual in a community, the methodology copes with the following three characteristics: (1) ad hoc group formation, (2) context-aware group need identification, and (3) using mobile devices working in- and out-doors. NAMA-US, an RFID-based prototype system, has been developed to show the feasibility of the idea proposed in this paper.

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A Wireless Optical Identification System Using Solar Cells (솔라 셀을 이용한 무선광 인식 장치)

  • Lee, Seong-Ho
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.5
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    • pp.494-500
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    • 2010
  • In this paper, we newly propose a wireless optical identification system and carried out experiments. A wireless optical identification system consists of a reader and a transponder. The configuration of a reader is the same as that of a transponder, which uses LED light as transmission media and detects the signal light with a solar cell. Optical alignment with a lens is not required because the absorption area of a solar cell is wide and flat, and it is very easy to attach a solar cell on the surface of an object. As the light wavelength does not interfere with radio frequency, a wireless optical identification system shows stable operation. In experiments, we realized a wireless optical identification system that automatically identifies the transponder data at a distance of 1 m using solar cells.

Damage identification of vehicle-track coupling system from dynamic responses of moving vehicles

  • Zhu, Hong-Ping;Ye, Ling;Weng, Shun;Tian, Wei
    • Smart Structures and Systems
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    • v.21 no.5
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    • pp.677-686
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    • 2018
  • The structural responses are often used to identify the structural local damages. However, it is usually difficult to gain the responses of the track, as the sensors cannot be installed on the track directly. The vehicles running on a track excite track vibration and can also serve as response receivers because the vehicle dynamic response contains the vibration information of the track. A damage identification method using the vehicle responses and sensitivity analysis is proposed for the vehicle-track coupling system in this paper. Different from most damage identification methods of vehicle-track coupling system, which require the structural responses, only the vehicle responses are required in the proposed method. The local damages are identified by a sensitivity-based model updating process. In the vehicle-track coupling system, the track is modeled as a discrete point supported Euler-Bernoulli beam, and two vehicle models are proposed to investigate the accuracy and efficiency of damage identification. The measured track irregularity is considered in the calculation of vehicle dynamic responses. The measurement noises are also considered to study their effects to the damage identification results. The identified results demonstrate that the proposed method is capable to identify the local damages of the track accurately in different noise levels with only the vehicle responses.

Survey on the Korean MCS Systems and Development Issues (국내 MCS 시스템 현황 및 발전 방향)

  • Kim, Geon-Ung;Park, Gyei-Kark;Choi, Jo-Cheon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.2019-2029
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    • 2009
  • There are several MCS(Monitoring, Control and Surveillance) systems for maritime safety and security in Korea; VMS (Vessel Monitoring System) that based on the AIS(Automatic Identification System), and the LRIT(Long-Range Identification and Tracking), the Vessel Free Pass System that based on the RFID(Radio Frequency IDentification), the Fisheries Information Network that provided by the National Federation of Fisheries Cooperatives. This paper surveys the fundamental technologies of MCS systems, and compares the role and function of them. It also surveys the development direction of each systems and research topics for cooperation of them.

The Parameter Estimation of DC-DC Converter by System Identification Method (시스템 식별 기법을 이용한 DC-DC 컨버터 파라메터 추정)

  • Jeon, Jin-Hong;Kim, Tae-Jin;Kim, Kwang-Su;Kim, Kwang-Hwa
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.503-506
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    • 2003
  • In this paper, we present the results of parameter estimation for do-dc converter model by system identification. The parameter estimation for dc-dc converter aims at the diagnosis of its operating status. we applied the system identification method for parameter estimation. For verification of estimated parameter, we compare bode plot of estimated system transfer function and measurement results of HP4194 instrument.

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Design of a Hierarchically Structured Gas Identification System Using Fuzzy Sets and Rough Sets (퍼지집합과 러프집합을 이용한 계층 구조 가스 식별 시스템의 설계)

  • Bang, Young-Keun;Lee, Chul-Heui
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.3
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    • pp.419-426
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    • 2018
  • An useful and effective design method for the gas identification system is presented in this paper. The proposed gas identification system adopts hierarchical structure with two level rule base combining fuzzy sets with rough sets. At first, a hybrid genetic algorithm is used in grouping the array sensors of which the measured patterns are similar in order to reduce the dimensionality of patterns to be analyzed and to make rule construction easy and simple. Next, for low level identification, fuzzy inference systems for each divided group are designed by using TSK fuzzy rule, which allow handling the drift and the uncertainty of sensor data effectively. Finally, rough set theory is applied to derive the identification rules at high level which reflect the identification characteristics of each divided group. Thus, the proposed method is able to accomplish effectively dimensionality reduction as well as accurate gas identification. In simulation, we demonstrated the effectiveness of the proposed methods by identifying five types of gases.

Korean Semantic Role Labeling Using Structured SVM (Structural SVM 기반의 한국어 의미역 결정)

  • Lee, Changki;Lim, Soojong;Kim, Hyunki
    • Journal of KIISE
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    • v.42 no.2
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    • pp.220-226
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    • 2015
  • Semantic role labeling (SRL) systems determine the semantic role labels of the arguments of predicates in natural language text. An SRL system usually needs to perform four tasks in sequence: Predicate Identification (PI), Predicate Classification (PC), Argument Identification (AI), and Argument Classification (AC). In this paper, we use the Korean Propbank to develop our Korean semantic role labeling system. We describe our Korean semantic role labeling system that uses sequence labeling with structured Support Vector Machine (SVM). The results of our experiments on the Korean Propbank dataset reveal that our method obtains a 97.13% F1 score on Predicate Identification and Classification (PIC), and a 76.96% F1 score on Argument Identification and Classification (AIC).

A Study on Modeling and Identification for the Magnetic Bearing System (자기 베어링 시스템의 모델링 및 동정에 관한 연구)

  • Shim, S.H.;Kim, C.H.;Yang, J.H.
    • Journal of Power System Engineering
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    • v.5 no.4
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    • pp.44-52
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    • 2001
  • This paper considers a modeling and identification for the MIMO magnetic bearing system. To obtain the nominal plant transfer functions, we have experimented on the frequency response by a closed-loop identification method because the system is unstable essentially. We suggest a method of curve-fitting for obtaining the transfer function from the frequency responses by using the system's modeling structure and two controllers which are different from each other. From the frequency response results, we found the effects of coupling by opposing controllers. And using this effects and the system's modeling structure, we could obtain the transfer functions of which have the same modularized denominators.

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