• Proceedings of the Korea Database Society Conference
• /
• 1998.09a
• /
• pp.475-505
• /
• 1998

With rapid progresses in information technologies, managing enterprise network resources as a whole becomes more important. Telecommunication Management Network (TMN) has been used to integrate network elements. TMN is complex to develop and manage because it has a centralized management service. Common Object Request Broker Architecture (CORBA) can overcome this complexity by the use of transparent distributed object processing mechanism. Therefore, the main objective of this paper is to integrate TMN service with CORBA. A network management repository is built for this integration. In addition, a prototype that can partially support network management service is implemented to illustrate the usefulness of this repository.

• Proceedings of the KIEE Conference
• /
• 2005.07d
• /
• pp.2771-2773
• /
• 2005

In network human-robot interaction, human can access services of a robot system through the network The communication is done by interacting with the distributed sensors via voice, gestures or by using user network access device such as computer, PDA. The service organization and exploration is very important for this distributed system. In this paper we propose a new agent-based framework to integrate partners of this distributed system together and help users to explore the service effectively without complicated configuration. Our system consists of several robots. users and distributed sensors. These partners are connected in a decentralized but centralized control system using agent-based technology. Several experiments are conducted successfully using our framework The experiments show that this framework is good in term of increasing the availability of the system, reducing the time users and robots needs to connect to the network at the same time. The framework also provides some coordination methods for the human robot interaction system.

• Proceedings of the KIEE Conference
• /
• 2001.05a
• /
• pp.42-45
• /
• 2001

The islanding protection for distributed resources (DR) becomes an important and emerging issue in power system protection since the distributed generator installations are rapidly increasing and most of the installed systems are interconnected with distribution network. In order to avoid the negative impacts on distributed network resulting from islanding operations of DR, it is necessary to detect the loss of mains (LOM) effectively. This paper presents a new LOM detection method using the rate of change in total harmonic distortion (THD) of current. The proposed method effectively detects LOM of the DR unit operating in parallel with the distribution network. We also verified the efficiency of the proposed method using the radial distribution network of IEEE 34 bus model.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.11C
• /
• pp.1040-1045
• /
• 2002

This paper focuses on a hash-based, distributed Wet caching network that eliminates inter-cache communication. An agent program on cache servers, a mapping program on the DNS server, and other components comprised in a distributed Web caching network were modified and developed to implement a so-called "consistent" hashing. Also, a dynamic load balancing algorithm is proposed to address the load-balancing problem that is a key performance issue on distributed architectures. This algorithm effectively balances the load among cache servers by distributing the calculated amount of mapping items that have higher popularity than others. Therefore, this developed network can resolve the imbalanced load that is caused by a variable page popularity, a non-uniform distribution of a hash-based mapping, and a variation of cache servers.

• Journal of Electrical Engineering and Technology
• /
• v.13 no.2
• /
• pp.637-647
• /
• 2018

In this paper, we propose a method to search candidates of network reconfiguration to restore distribution system with distributed energy resources using a level-based tree search algorithm. First, we introduce a method of expressing distribution network with distributed energy resources for fault restoration, and to represent the distribution network into a simplified graph. Second, we explain the tree search algorithm, and introduce a method of performing the tree search on the basis of search levels, which we call a level-based tree search in this paper. Then, we propose a candidate search method for fault restoration, and explain it using an example. Finally, we verify the proposed method using computer simulations.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.55 no.2
• /
• pp.73-77
• /
• 2006

A server is simply a computer that is running software that enables it to serve specific requests from other computers, called 'clients.' Distributed systems are considered by some to be the 'next wave' of computing. A collection of probably heterogeneous distribution systems is transparent to the user so that the system appears as one local machine. This paper is going to search about whole of Client/Server distributed systems environment through network game. This paper presents game by one example of network game. The ladder game uses JAVA and embody to do random every time using Random function and remainder operation repeatedly. Analyze execution principle of network game through this tame and investigate about Client/Server's distributed environment through this.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 1999.10a
• /
• pp.163-175
• /
• 1999

As the size and complexity of network increase, Distributed Systems Management (DSM) will be significant issue within information network in order to increase the high reliability and to improve the flexibility of network management. The OSI management model has several problems. The key problems are that it does not fully address the problems of how to develop communication protocol in support of DSM, and how to classify the management connection criteria. In this paper, to solve first problem described above, this paper propose the connectionless CMIP(Common Management Information Protocol) to accomplish for effectively managing the distributed management system, and indicate its efficiency; this protocol is available to negotiate among the managing systems, handle the dynamic information. To work out second problem, we introduce the connection criteria in the hierarchy of management systems, and finally evaluate the efficiency of a suggested protocol during cooperative negotiation among the managing systems.

• Journal of Internet Computing and Services
• /
• v.5 no.3
• /
• pp.87-98
• /
• 2004

There are 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 and 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 modeling framework using RM-ODP (Reference Model Open Distributed Processing) to manage that network In the form of integrated hierarchy, This paper adopts the object-oriented development methodology with UML (Unified Modeling Language) and designs and implements the HFC network of DOCSIS as an example of the subscriber network.

• Journal of Institute of Control, Robotics and Systems
• /
• v.6 no.10
• /
• pp.911-917
• /
• 2000

As many sensors and actuators are used in various automated systems, the application of network to real-time distributed control system is gaining acceptance in many industries. In order to take advantages of networking, however, the network should be carefully designed to satisfy real-time distributed control. This paper presents an implementation method of closed-loop control using Profibus-FMS. In order to implement a closed-loop control system, we used industrial computers with Profibus-FMS network cards and a DC servo motor. Through various experiments, the step response of the control system with network was compared with the reference response without network.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.2 no.3
• /
• pp.135-149
• /
• 2008

Traditional attack detection schemes based on packets or flows have very high computational complexity. And, network based anomaly detection schemes can reduce the complexity, but they have a limitation to figure out the pattern of the distributed global scale network attack. In this paper, we propose an efficient and fast method for detecting distributed global-scale network attack symptoms in high-speed backbone networks. The proposed method is implemented at the aggregate traffic level. So, our proposed scheme has much lower computational complexity, and is implemented in very high-speed backbone networks. In addition, the proposed method can detect attack patterns, such as attacks in which the target is a certain host or the backbone infrastructure itself, via collaboration of edge routers on the backbone network. The effectiveness of the proposed method are demonstrated via simulation.