• Journal of Advanced Marine Engineering and Technology
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• v.28 no.4
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• pp.603-610
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• 2004

Time delays are included in most of actual systems, and some of which are shown as time varying. To analyze the time varying time delay system in the time domain. a useful delay module to express the function as a tool is much helpful to get corresponding outputs under given conditions. A method is proposed here to design the algorithm of time delay module for simulation or control purposes, including the problems of initializing and reallocating data in buffer. After classifying the time varying time delay into the distributed mode and lumped mode, an object to describe delay module is configured and tested under the defined input signal and given time delay variation. The simulation results show that the output of module matches reasonably with the case of real system.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.6
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• pp.23-37
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• 2004

Since java thread is an object which is treated as independent process within one execution space in the multiprocessing environment, we can use it for independent process of parallel processing. Using thread and synchronization mechanism of java enables us to write parallel application program easily. Therefore, a lot of results are exist which is apply the feature of java that support parallel processing to the distributed computing environment. In this paper, we introduce a system of environment that support parallel execution of thread which is included in legacy java program. The system named TORB(Transparent Object Request Broker) enables us parallel execution of legacy java program after simple converting process, since it support the feature of programming transparency. TORB is extended version of distributed programming tool that is published by our research team. And it had only typical distributed processing feature that is execute a specified function at the specified computer.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.1
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• pp.74-79
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• 2006

In this paper, we present a technique for distributed media object live streaming using RMI and JMF. Then, we handle technique that simplify complex control of distributed objects using RMI and do one-to-many live streaming in network environment that do not support multicast using JMF. It can separate transmission and control to use RMI and JMF based on Java. Consequently the technique is available in development of multimedia service application that is independent to platform.

• IE interfaces
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• v.15 no.1
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• pp.10-19
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• 2002

New trends such as electronic commerce, virtual organizations, e-business applications, etc. increase the dependence of production management on information software systems and contribute to the needs for global, distributed object systems. This paper presents a component based approach for production management systems under the multi-tier distributed information system architecture using UML(Unified Modeling Language), CORBA(Common Object Request Broker Architecture) and XML(eXtensible Markup Language) technologies, and propose rules for mapping a UML class diagram to a XML DTD (Document Type Definition). And we adapt it to the prototype system implementation. The components are implemented by CORBA and we use XML messages for the information exchange between components.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.5 no.1
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• pp.46-51
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• 2005

Intelligent Space(ISpace) is the space where many intelligent devices, such as computers and sensors, are distributed. According to the cooperation of many intelligent devices, the environment, it is very important that the system knows the location information to offer the useful services. In order to achieve these goals, we present a method for representing, tracking and human following by fusing distributed multiple vision systems in ISpace, with application to pedestrian tracking in a crowd. And the article presents the integration of color distributions into particle filtering. Particle filters provide a robust tracking framework under ambiguity conditions. We propose to track the moving objects by generating hypotheses not in the image plan but on the top-view reconstruction of the scene. Comparative results on real video sequences show the advantage of our method for multi-object tracking. Simulations are carried out to evaluate the proposed performance. Also, the method is applied to the intelligent environment and its performance is verified by the experiments.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3340-3349
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• 1999

Supporting object group on distributed object system give merits such as load balancing, fault tolerance and high availability. In this paper, we describe a CORBA ORB that has been designed to support object group based on active replication. The ORB supports the operational model in which it uses the IIOP for communication between client and server and total ordered multicast protocol for consistency control among group members. And through extension of ORB, it provides functions required for support of object group. Since it provides transparency of object replication, the ORB is interoperable with the existing CORBA products. It make possible for existing server application to be easily extended to application supporting object group as adding interface functions which should be used for building applications is minimized. A prototype is implemented, and performance of the replicated object group is tested and compared with a single object invocation.

• The Journal of Information Technology and Database
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• v.7 no.1
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• pp.17-26
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• 2000

To provide highly available services in the distributed object system, it is required to support the object group. The state machine approach and primary-backup approach are proposed as two representative approaches for support of object group. The primary-backup approach does not only give merits such as transparency of object group and non-deterministic execution but also require less resource than state machine approach. This paper describes an extension of CORBA that is required to support of the primary-backup object group. In this paper, the state of backup is synchronized with primary through the atomic multicast protocol whenever the request of client is executed at primary. As a result, it does not require message logging and check pointing. The object group of this paper also provides fast response time in case of failure of the primary since it makes primary election unnecessary. And through an extension of IDL, it makes possible to avoid consistency control depending on characteristic of application. A prototype has been implemented and the performance of object group has been compared with a single object invocation.

• The Journal of Society for e-Business Studies
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• v.4 no.1
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• pp.145-157
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• 1999

The challenge is to maximize the time-to-market benefits of concurrent engineering while maintaining control of data and distributing it automatically to the people who need it when they need it. The way PDM systems cope with this challenge is that master data is held only once in a secure vault where its integrity can be assured and all changes to it monitored, controlled and recorded. The structure of PDM is various from vendor, but they have common module. That is PDM and it is most important. The goal is to design the workflow in PDM using object-oriented modeling method. The past methods have concentrated on the flow between workflow engine and agent, but this paper will focus on task. We will model task as individual object. This paper uses OMT(Object Modeling Technique) by James Rumbaugh for base modeling tool and uses DCOM(Distributed Component Object Model) for base ORB(Object Request Broker). Research object is to design the static object model, to design state change by dynamic model and to design data transition by functional model.

• The Transactions of the Korea Information Processing Society
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• v.4 no.11
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• pp.2721-2731
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• 1997

Distributed programming can be greatly simplified by language support for distributed communication. Many web-browsers now offer some form of active objects and the number and types of them are growing daily in interesting and innovative ways. Java applets are well known as one kind of active object related to web-browser. This paper focuses in distributed active objects which is one kind of active objects that can communicate with other active objects located in different machines across the Internet. Java RMI and CORBA IDL are two major programming environments for distributed active objects which are non compatible with each other. To make discussion concrete, we introduce a single application as implemented on two environments : the HORM, adopting RMI mechanism, and the OrbixWeb2.0.1, adopting CORBA specification, respectively. Binding, inheritance, polymorphism, object passing and callbacks across the machine boundary in distributed programming environments are issued. The results show that some differences in the implementation of distributed active objects can have a significant impact on how distributed applications are structured. The comparison between two implementations on the programming environments will be the basis for building the translation system between HORB to OrbixWeb and vice versa.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.5
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• pp.1400-1420
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• 2012

Object detection and tracking using visual sensors is a critical component of surveillance systems, which presents many challenges. This paper addresses the enhancement of object detection and tracking via the combination of multiple visual sensors. The enhancement method we introduce compensates for missed object detection based on the partial detection of objects by multiple visual sensors. When one detects an object or more visual sensors, the detected object's local positions transformed into a global object position. Local and global information exchange allows a missed local object's position to recover. However, the exchange of the information may degrade the detection and tracking performance by incorrectly recovering the local object position, which propagated by false object detection. Furthermore, local object positions corresponding to an identical object can transformed into nonequivalent global object positions because of detection uncertainty such as shadows or other artifacts. We improved the performance by preventing the propagation of false object detection. In addition, we present an evaluation method for the final global object position. The proposed method analyzed and evaluated using case studies.