• Journal of Information Technology Services
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• v.8 no.1
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• pp.193-202
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• 2009

Cloud computing emerges as a new computing paradigm which targets reliable and customizable services. The term builds on decades of research in virtual machine, distributed and parallel computing, utility computing, and more recently networking, web service, and software as a service. In this paper, we provide a seamless connection migration of web services. This is useful for cloud computing environment in which many client terminals have mobility. With the wireless internet facility, those mobile users can move place to place during internet communication. Therefore, we provide solutions to the two major problems in current virtualization based migration: communication failure problems and connection re-establishment. Communication channel flushing by zero window notification helps to resolve the communication failure problems and TCP port inheritance prevents connection re-establishment errors during socket reconstruction. Thus, our web service migration facility is now able to preserve open network connections, and even for server sockets. This is a highly transparent approach, in that we did not Introduce additional messages for channel flushing and did not make any modification to the TCP protocol stack. Experimental results show that the overhead due to connection migration of web services is almost negligible when compared with time to take the conventional web service migration.

• The Transactions of the Korea Information Processing Society
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• v.4 no.9
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• pp.2391-2402
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• 1997

TINA is the Open Networking Architecture which as newly introduced software architecture shares the network managements and the service managements on the Distributed Processing Environment. In this paper, based on the concepts and principles defined up to now, we implement and test the CM(Connection Management) Package included in CM which is one of the six functional areas into which TINA Management Architecture is devided. Before the implementation we learn the basic concepts accepted by the four architectures in TINA, and medelling concept of the CM. The interfaces of eaxh information objects explain the functions of computational objects implemented, and the message flows among the computational objects show the connection setup and release procedures.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.908-911
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• 2004

There are various researches on mobile robot systems. Connection method between server and client of mobile robot system is one of them. In the case of mobile robot system, when connection method between server and client is wireless than wire, applications may be expanded. Also in remote monitoring environment using mobile robot system, we are interested in an effective transmission of the image information between server and client. In this paper, Bluetooth is used for connection method between server and client. One of the major applications of Bluetooth is the cable replacement for mobile and peripheral devices. Using Bluetooth, we propose the control method of mobile robot system. Bluetooth offers fast and reliable transmissions of both voice and data over the globally available 2.4GHz ISM (Industrial, Scientific and Medical) band. It has the advantage of small size, low power and low cost. It has the disadvantage of limited range and limited bandwidth. Also in order to transfer effectively image information between remote site(server) and mobile robot system(client) using Bluetooth, we applied to MPEG-2 and MPEG-4 image compression techniques and the results are compared with each other.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.10
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• pp.1183-1192
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• 1988

In this paper, we describe heuristic information-added morphological dictionary and connection table, and automatic MUNJEUL separation process on the basis of least cost method for efficient morphological analysis. It is simplified the composition of connection and inflective word information by mutually interconnect conjugation table with connection tables. As a result, the applicability of system is increased. Translation dictionary consists of analysis and generation part and, increase the applicability by describing frequently using termination phrase which is extracted statistically as idiom and the procedure directly on the dictionary for the efficiency of analysis process and more natural generation of translation sentence.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1501-1505
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• 2004

The authentication system of high-speed internet in IP-infra is not warm enough to administration of systematic authentication information for user's legalization, connection right and resources allocation in order to both methods of authentication-unauthentication connection system according to transmission method . Also unauthentication connection raises a difficulty condition to user's needs satisfaction in order to a load weighting of system and network and a drop of transmission speed. Accordingly, this study brings forth authentication system construction in a high-speed IP infrastructure using spam sever able to construct the suitable network condition according to unifying authentication-unauthentication system for single authentication system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.200-203
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• 2005

Most of electrical fires are caused by short circuits, overheating of wires, deterioration and incomplete connection of wiring devices. The last two cases are predictable before the occurrence of fire because of its slow progress. In this paper, we have simulated the discharge signals caused by the deterioration and incomplete connection of wiring devices using an aged concent to provide information on the characteristics of discharge signals. From the experimental data, we could characterize the frequency spectrums of the discharge signals depending on the cases. The higher frequency components of the signal are attenuated by the capacitance and inductance of power lines as the measuring point is getting away from the discharges. Main frequency components of the discharge signal are existent at 600 kHz - 1.5 MHz in incomplete connections and at 210 kHz - 8 Mhz in deteriorations of the concent.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.2
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• pp.152-160
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• 2019

In this study, we propose a piping material supply management method using CAD system. The piping materials installed in super large offshore plants have very complicated connection conditions. Therefore, it is very difficult to determine the order of receipt of a large number of installation materials. Therefore, we have developed a system that can automatically check the preparation rate of installation materials prior to the installation process. We have developed an algorithm to obtain connection information among installation items from PDMS system. We have developed an algorithm that can determine the order of installation materials to be installed using the connection information. The order of the installation material is determined by taking into account the constraint conditions for the complete installation of the piping material. We confirm the effectiveness of the developed algorithms in the operating system. This system is also used to manage installation schedules and plan the installation manpower.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.4
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• pp.861-866
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• 2014

The scale of national research and development work is expanded gradually and grows bigger, so necessity of building system rises to guarantee more objective and fairer selection of business and clarity of budget administration according to active progress of convergence between study territories. In the study, standard frame work is suggested for information connection between dissimilarities, and based on this work; the study considers the system for information connection of digital budget accounting system handling budget and accounting of national finance and national science technology knowledge information system that is in charge of result administration and result evaluation of national research and development work, so suggests application plan of standard frame work connected with information solving current state and problems for connection.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.45-57
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• 2005

In this paper, we extend the performance of bidirectional TCP connection over end-to-end network that uses transfer rate-based flow and congestion control. The sharing of a common buffer by TCP packets and acknowledgement has been known to result in an effect called ack compression, where acks of a connection arrive at the source bunched together, resulting in unfairness and degraded throughput. The degradation in throughput due to bidirectional traffic can be significant. Even in the simple case of symmetrical connections with adequate window size, the connection efficiency is improved about 20% for three levels of background traffic 2.5Mbps, 5.0Mbps and 7.5Mbps. Otherwise, the throughput of jitter is reduced about 50% because round trip delay time is smaller between source node and destination node. Also, we show that throughput curve is improved with connection rate algorithm which is proposed for TCP congetion avoidance as a function of aggressiveness threshold for three levels of background traffic 2.5Mbps, 5Mbps and 7.5Mbps. By analyzing the periodic bursty behavior of the source IP queue, we derive estimated for the maximum queue size and arrive at a simple predictor for the degraded throughput, applicable for relatively general situations.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.2948-2957
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• 2000

A broadband access network in B- ISDN subscriber network, plays a role of concentration or multiplexing of various subscribers into a service node. To establish an end-to-end ATM connection, interworking functions between \'B5.2 interface's connection protocol and the signalling protocol, are perfonned at the service node. A sequential interworking model and a parallel interworking model were proposed for these interworking functions. The sequential interworking model proceeds the signalling protocol of network node after the response of VB5.2 interface protocol. On the other hand, the parallel interworking model proceeds the signalling protocol and the VB5.2 interface protocol simultaneously. In this paper, we analyze and simulate above two interworking models in tenns of a connection setup delay and completion ratio, when call requests with eBR and VBR transfer capability arrive at the service node. We observed that the completion ratios of the two interworking models are quite closed. However the connection setup delay of parallel interworking model is improved by about 33% compared with that of the sequential interworking model.