• The Transactions of the Korea Information Processing Society
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• v.2 no.1
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• pp.12-22
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• 1995

When we integrate schema of distributed local databases, we mean entity integration as central concept of schema integration, and semantic of entity affects several factors. Thus the schema integration in distributed database environment starts from definition of domain relation among entity types of local schemas. Moreover, the domain relation defined by designer needs some works for confidence and validation of schema integration system. But this work was not presented in previous integration system. In this paper, we define object oriented integration for schema integration of local databases in distributed system environment, present models to verify validation on its integration, and implement the validation system.

• Journal of Korea Multimedia Society
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• v.10 no.12
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• pp.1679-1686
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• 2007

In this paper, we introduce the sharable and reusable learning objects which are suitable for XML Web services in e-learning systems. These objects are extracted from the principles of pedagogical paradigms for reusable learning units. We call them LIO (Learning Item Object) objects. Existing models, such as Web-hosted and ASP-oriented service model, are difficult to cooperate and integrate among the different kinds of e-learning systems. So we developed the LIO objects that are suitable for XML Web services. The reusable units that are extracted from pedagogical paradigms are tutorial item, resource, case example, simulation, problems, test, discovery and discussion. And these units correspond to the LIO objects in our learning object model. As a result, the proposed model is that learner and instruction designer should increase the power of understanding about learning contents that are based on pedagogical paradigms. By using XML Web services, this guarantees the integration and interoperation of the different kinds of e-learning systems in distributed environments and so educational organizations can expect the cost reduction in constructing e-learning systems.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.6
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• pp.958-965
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• 2002

Current research for software architecture views and models a software system as a set of components and connectors. Components are abstractions of system level computational entities. Connectors are abstractions of components interrelationships. In this paper, we focus on connectors for the JavaBeans-based systems that are built using object integration technologies like CORBA. We present connector model in JavaBeans-based system for object-oriented component integration. We start with a discussion of related work of software architecture research and object-oriented modeling that focuses on the description of component collaborations. We propose connectors as transferable abstractions of system level component interconnection and inter-operation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.291-294
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• 2001

This Current research for software architecture views and models a software system as a set of components and connectors. Components are ions of system level computational entities, connectors are ions of component interrelationships. In his paper, we focus attention on connectors for the Java Beans-based systems that are built using object integration technologies like CORBA. We present connector model in lava Beans-based system for object-oriented component integration. We start with a discussion of related work of software architecture research and of Object-Oriented modeling that focuses on the description of component collaborations. We propose connectors as transferable ions of system level component interconnection and inter-operation. Connectors are architectural ions of component coordination in the architecture of a system only. Connectors describe a collaboration rationale for component adaptations, which are then modeled in the concrete architecture of a system.

• Proceedings of the CALSEC Conference
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• 1999.07b
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• pp.563-574
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• 1999

In CALS/EC environment, there are geographically dispersed heterogeneous databases and various applications. Integrated database environment provides transparent access mechanism for heterogeneous and distributed databases and interoperability between applications in various platforms. Because elements exist geographically in integrated database environment, directory service is necessary for providing unique access mechanism for elements. In this paper, we design a directory service using CORBA based access interface and object-oriented DIB model for accessing transparently to elements and interoperability with other information system.

• Journal of Korea Multimedia Society
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• v.7 no.2
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• pp.283-291
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• 2004

Internet Service Subscribers Network has a new role of providing the various multimedia services to the home. However, there exist several types of distributed subscribers network using Asymmetric Digital Subscriber Line (ADSL), Very high-bit rate Digital Subscriber Line (VDSL), and Data Over Cable Service Interface Specifications (DOCSIS). The efficient and concentrated network management of those several distributed subscribers networks with resources require the general information model of network, which has abstract and conceptional managed objects independent of type of network and its equipment to manage the integrated subscriber network. This paper presents the general Internet subscribers network model of the managed object to manage that network in the form of integrated hierarchy This paper adopts the object-oriented development methodology with UML and designs and implements the integrated subscribers NMS of cable data network and VDSL network as examples of the subscriber networks.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.7 no.3
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• pp.79-94
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• 1997

OMG (Object Management Group) published a security service specification, called CORBA (Common Object Request Broker Architecture) security reference model because the integration of security and object-oriented techniques was critical for successful deployment of distributed object systems. The CORBA security reference model treats access control as an implementation independent semantic concept but has incomplete semantics of the access control function. Because of such imcompleteness it is difficult for the system administrator and the CORBA security implementor to have the same understanding for the meaning of access control in the CORBA security. We propose a formal model for access control the CORBA security using the formal description language, which is called Z language based on typed set theory. The proposed model provides concrete semantics of the access control function to both the system administrator and the implementor.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.10 no.2
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• pp.101-106
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• 2010

We propose an approach to estimate the real-time moving trajectory of an object in this paper. The object's position is obtained from the image data of a CCD camera, while a state estimator predicts the linear and angular velocities of the moving object. To overcome the uncertainties and noises residing in the input data, a Extended Kalman Filter(EKF) and neural networks are utilized cooperatively. Since the EKF needs to approximate a nonlinear system into a linear model in order to estimate the states, there still exist errors as well as uncertainties. To resolve this problem, in this approach the Kohonen networks, which have a high adaptability to the memory of the inputoutput relationship, are utilized for the nonlinear region. In addition to this, the Kohonen network, as a sort of neural network, can effectively adapt to the dynamic variations and become robust against noises. This approach is derived from the observation that the Kohonen network is a type of self-organized map and is spatially oriented, which makes it suitable for determining the trajectories of moving objects. The superiority of the proposed algorithm compared with the EKF is demonstrated through real experiments.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.6
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• pp.602-613
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• 2001

Recently, the computing has developing in distributed object computing environment for supporting a programming paradigm of distributed application requiring interoperability between heterogeneous clients and servers. It involves the complex networking and the object-oriented technologies for various multimedia application service. In this paper, we construct the real-time object group platform for solving the difficulties of managements of distributed objects and the real-time constraints by requiring for real-time service supporting of applications in distributed computing environment. The existing researches are being tried to only improving the performance of systems by using real-time CORBA itself, or modifying the part of CORBA compliance. Hence, we design a new model of real-time object group platform that can support the real-time requirement without modifying the ORB. The structure of our real-time object group analyzed and defined the requirement about object management and real-time application service sides. And the role of the components of real-time object group is divided into 2 classes for reducing the side effect of interoperability between management and service. Also, we considered how to transparently express the parameters of real-time properties for clients and developers of server's service objects. If the expression of real-time parameters is transparent, then the developer can easily extend the real-time parameters simply and flexibly. Therefore, in this paper we defined the role of components of platform and described functions of each component and designed and then implemented the real-time object group platform. Finally, we showed the execution procedures of implemented our platform for verifying the functionality.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.2
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• pp.120-134
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• 2000

In this paper we present a Distributed Object oriented Virtual computing Environment, called DOVE which consists of autonomous distributed objects interacting with one another via method invocations based on a distributed object model. DOVE appears to a user logically as a single virtual computer for a set of heterogeneous hosts connected by a network as if objects in remote site reside in one virtual computer. By supporting efficient parallelism, heterogeneity, group communication, single global name service and fault-tolerance, it provides a transparent and easy-to-use programming environment for parallel applications. Efficient parallelism is supported by diverse remote method invocation, multiple method invocation for object group, multi-threaded architecture and synchronization schemes. Heterogeneity is achieved by automatic data arshalling and unmarshalling, and an easy-to-use and transparent programming environment is provided by stub and skeleton objects generated by DOVE IDL compiler, object life control and naming service of object manager. Autonomy of distributed objects, multi-layered architecture and decentralized approaches in hierarchical naming service and object management make DOVE more extensible and scalable. Also,fault tolerance is provided by fault detection in object using a timeout mechanism, and fault notification using asynchronous exception handling methods