• Title/Summary/Keyword: distributed object

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Industrial Robot Control using the Distributed Adaptive Control Techniques (분산 적응제어 기법을 이용한 산업용 로버트 제어)

  • 정찬수;이상철
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.5 no.1
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    • pp.57-64
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    • 1991
  • The paper considers a distributed adaptive control technique for Industrial Robots which contribute to the factory automation. The control object is to tracking for a desired trajectories under various load conditions, rapidly against load variation. These control techniques divided whole system into subsystems which is controlled with the Nominal and Adaptational controllers. And also the asymptotic stability of these substem was proved. Simulation results shown that the proposed techniques was feasible in spite of nonlinear dynamics of robot manipulator and payload variations.

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Comparisons between Distributed Connections and Centralized Connections of Multimedia Streams for Computer-based Audio-Video Teleconferences (컴퓨터 영상회의 시스템을 위한 분산형과 집중형 스트림 연결 구조 비교)

  • Lee, Gyeong-Hui;Kim, Du-Hyeon;Im, Heon-Gyu;Im, Yeong-Hwan
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.3
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    • pp.591-607
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    • 1996
  • To support various multimedia applications. MuX server produces object-oriented and consistent interfaces for creation, copying, splitting, mixing and interleaving of streams. In this paper, we describes distributed connection structures and centralized connection structures which can be used in building a teleconferencing system using basic objects of MuX and compares merits and demerits of each structure from the viewpoint of multimedia related performance like delay and synchronization.

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Design Issues and QoS Negotiation Protocol Model for Networked Multimedia Systems (네트워크 멀티미디어 시스템 구현 이슈 및 QoS 협상 프로토콜 모델)

  • Lee, Won-Jun
    • The KIPS Transactions:PartC
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    • v.9C no.5
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    • pp.757-764
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    • 2002
  • This Paper describes our experiences with the design and implementation of a networked multimedia information management system in an object-oriented framework for distributed multimedia applications, and an integrated QoS-resource negotiation protocol which has been applied to a video server in our networked multimedia infrastructure. The salient features of our framework to support efficient multimedia streaming are explained. Next the paper explores the challenges faced in integrating the proposed QoS negotiation policy into the framework.

An Abnormal Breakpoint Data Positioning Method of Wireless Sensor Network Based on Signal Reconstruction

  • Zhijie Liu
    • Journal of Information Processing Systems
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    • v.19 no.3
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    • pp.377-384
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    • 2023
  • The existence of abnormal breakpoint data leads to poor channel balance in wireless sensor networks (WSN). To enhance the communication quality of WSNs, a method for positioning abnormal breakpoint data in WSNs on the basis of signal reconstruction is studied. The WSN signal is collected using compressed sensing theory; the common part of the associated data set is mined by exchanging common information among the cluster head nodes, and the independent parts are updated within each cluster head node. To solve the non-convergence problem in the distributed computing, the approximate term is introduced into the optimization objective function to make the sub-optimization problem strictly convex. And the decompressed sensing signal reconstruction problem is addressed by the alternating direction multiplier method to realize the distributed signal reconstruction of WSNs. Based on the reconstructed WSN signal, the abnormal breakpoint data is located according to the characteristic information of the cross-power spectrum. The proposed method can accurately acquire and reconstruct the signal, reduce the bit error rate during signal transmission, and enhance the communication quality of the experimental object.

Implementation of Non-SQL Data Server Framework Applying Web Tier Object Modeling (웹티어 오브젝트 모델링을 통한 non-SQL 데이터 서버 프레임웍 구현)

  • Kwon Ki-Hyeon;Cheon Sang-Ho;Choi Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.4B
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    • pp.285-290
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    • 2006
  • Various aspects should be taken into account while developing a distributed architecture based on a multi-tier model or an enterprise architecture. Among those, the separation of role between page designer and page developer, defining entity which is used for database connection and transaction processing are very much important. In this paper, we presented DONSL(Data Server of Non SQL query) architecture to solve these problems applying web tier object modelling. This architecture solves the above problems by simplifying tiers coupling and removing DAO(Data Access Object) and entity from programming logic. We concentrate upon these three parts. One is about how to develop the DAO not concerning the entity modification, another is automatic transaction processing technique including SQL generation and the other is how to use the AET/MET(Automated/Manual Execute d Transaction) effectively.

Content-based Rate control for Hybrid Video Transmission (혼합영상 전송을 위한 내용기반 율제어)

  • 황재정;정동수
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.8B
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    • pp.1424-1435
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    • 2000
  • A bit-rate controller that can achieve a constant bit rate when coding object-based video sequences is an important part to achieve an adaptation to bit-rate constraints, desired video quality, distribution of bits among objects, relationship between texture and shape coding, and determination of frame skip or not. Therefore we design content-based bit rate controller which will be used for relevant bit-rate control. The implementation is an extension of MPEG-4 rate control algorithm which employs a quadratic rate-quantizer model. The importance of different objects in a video is analyzed and segmented into a number of VOPs which are adaptively bit-allocated using the object-based modelling. Some test sequences are observed by a number of non-experts and interests in each object are analysed. The initial total target bit-rate for all objects is obtained by using the proposed technique. Then the total target bits are jointly analyzed for preventing from overflow or underflow of the buffer fullness. The target bits are distributed to each object in view of its importance, not only of statistical analysis such as motion vector magnitude, size of object shape, and coding distortion of previous frame. The scheme is compared with the rate controller adopted by the MPEG-4 VM8 video coder by representing their statistics and performance.

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Computer Vision-based Continuous Large-scale Site Monitoring System through Edge Computing and Small-Object Detection

  • Kim, Yeonjoo;Kim, Siyeon;Hwang, Sungjoo;Hong, Seok Hwan
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.1243-1244
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    • 2022
  • In recent years, the growing interest in off-site construction has led to factories scaling up their manufacturing and production processes in the construction sector. Consequently, continuous large-scale site monitoring in low-variability environments, such as prefabricated components production plants (precast concrete production), has gained increasing importance. Although many studies on computer vision-based site monitoring have been conducted, challenges for deploying this technology for large-scale field applications still remain. One of the issues is collecting and transmitting vast amounts of video data. Continuous site monitoring systems are based on real-time video data collection and analysis, which requires excessive computational resources and network traffic. In addition, it is difficult to integrate various object information with different sizes and scales into a single scene. Various sizes and types of objects (e.g., workers, heavy equipment, and materials) exist in a plant production environment, and these objects should be detected simultaneously for effective site monitoring. However, with the existing object detection algorithms, it is difficult to simultaneously detect objects with significant differences in size because collecting and training massive amounts of object image data with various scales is necessary. This study thus developed a large-scale site monitoring system using edge computing and a small-object detection system to solve these problems. Edge computing is a distributed information technology architecture wherein the image or video data is processed near the originating source, not on a centralized server or cloud. By inferring information from the AI computing module equipped with CCTVs and communicating only the processed information with the server, it is possible to reduce excessive network traffic. Small-object detection is an innovative method to detect different-sized objects by cropping the raw image and setting the appropriate number of rows and columns for image splitting based on the target object size. This enables the detection of small objects from cropped and magnified images. The detected small objects can then be expressed in the original image. In the inference process, this study used the YOLO-v5 algorithm, known for its fast processing speed and widely used for real-time object detection. This method could effectively detect large and even small objects that were difficult to detect with the existing object detection algorithms. When the large-scale site monitoring system was tested, it performed well in detecting small objects, such as workers in a large-scale view of construction sites, which were inaccurately detected by the existing algorithms. Our next goal is to incorporate various safety monitoring and risk analysis algorithms into this system, such as collision risk estimation, based on the time-to-collision concept, enabling the optimization of safety routes by accumulating workers' paths and inferring the risky areas based on workers' trajectory patterns. Through such developments, this continuous large-scale site monitoring system can guide a construction plant's safety management system more effectively.

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Implementation of Object-oriented Active Rule System in Distributed Environment (분산환경에서 객체지향 능동 규칙 시스템 구현)

  • Go, Goeng-Uk;Yu, Sang-Bong;Kim, Gi-Chang;Cha, Sang-Gyun
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.11
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    • pp.2875-2888
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    • 1999
  • In this paper we present compiler-based active rule system to efficiently maintain spatial integrity constraints in a heterogeneous, distributed environment. Specially, the prototype active rule system presented has been developed as a component of a whole middleware system called SDBC(Spatile DataBase Connectivity). Due to this reason, our active rule system is provided for heterogeneous ODBMSs in a distributed environment and used to define spatial integrity constraints using the active rules in E-C-A(Event-Condition-Action) type. Using this active rule system, an application programmer can free himself from a heavier burden on the integrity maintenance of application objects. In the compiler-based approach, active rules applicable to events raised by a database program are directly inserted into the program in a function type by the preprocessor, and then they are compiled with the application program source codes. One advantage of this approach is that there is no run-time overhead accompanied by monitoring all the database transitions when preprocessed program is executed. This active rule system also provides facilities to manage changed rules and dynamically interpret those rules at run-tuime.

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A framework for distributed analytical and hybrid simulations

  • Kwon, Oh-Sung;Elnashai, Amr S.;Spencer, Billie F.
    • Structural Engineering and Mechanics
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    • v.30 no.3
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    • pp.331-350
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    • 2008
  • A framework for multi-platform analytical and multi-component hybrid (testing-analysis) simulations is described in this paper and illustrated with several application examples. The framework allows the integration of various analytical platforms and geographically distributed experimental facilities into a comprehensive pseudo-dynamic hybrid simulation. The object-oriented architecture of the framework enables easy inclusion of new analysis platforms or experimental models, and the addition of a multitude of auxiliary components, such as data acquisition and camera control. Four application examples are given, namely; (i) multi-platform analysis of a bridge with soil and structural models, (ii) multiplatform, multi-resolution analysis of a high-rise building, (iii) three-site small scale frame hybrid simulation, and (iv) three-site large scale bridge hybrid simulation. These simulations serve as illustrative examples of collaborative research among geographically distributed researchers employing different analysis platforms and testing equipment. The versatility of the framework, ease of including additional modules and the wide application potential demonstrated in the paper provide a rich research environment for structural and geotechnical engineering.

Investigating the Implications of the Connectionist Views of the Concept in Conceptual Learning of Science (연결주의 개념관이 과학 개념학습에 주는 시사점 고찰)

  • 정용재;송진웅
    • Journal of Korean Elementary Science Education
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    • v.23 no.3
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    • pp.251-265
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    • 2004
  • Conceptual teaming has been one of the important issue in science education, and its theory and method has been interacted with the studies of philosophy of science, cognitive science, and cognitive psychology. The last two decades have witnessed a remarkable growth of the study on brain-style computation, i.e. connectionism. This study aimed to investigate the properties of the connectionist views of the concept and its implications in the conceptual learning of science. In connectionist views, a concept was represented as a pattern of activity distributed over many connected units, and a kind of network composed of many sub-concept units. And the 'distributed representation' had the features of the constructivity, the automatically generalization, and the tunability. On the base of these views, it was suggested that (ⅰ) 'Typically-Perceived-Situation', a kind of mental representation rising spontaneously in an individual mind when someone is thinking about any object, should be highlighted, and (ⅱ) the roles of the sub-concept units in formation of concept and the resolution of concept into the sub-concept units should be highlighted. Finally the meanings of these implications in conceptual teaming of science are discussed.

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