• Journal of KIISE:Computer Systems and Theory
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• v.33 no.3
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• pp.193-204
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• 2006

In most existing distributed Web systems, incoming requests are distributed to servers via Domain Name System (DNS). Although such systems are simple to implement, the address caching mechanism easily results in load unbalancing among servers. Moreover, modification of the DNS is necessary to load considering the server's state. In this paper, we propose a new dynamic load balancing method using dynamic DNS update and round-robin mechanism. The proposed method performs effective load balancing without modification of the DNS. In this method, a server can dynamically be added to or removed from the DNS list according to the server's load. By removing the overloaded server from the DNS list, the response time becomes faster. For dynamic scheduling, we propose a scheduling algorithm that considers the CPU, memory, and network usage. We can select a scheduling policy based on resources usage. The proposed system can easily be managed by a GUI-based management tool. Experiments show that modules implemented in this paper have low impact on the proposed system. Furthermore, experiments show that both the response time and the file transfer rate of the proposed system are faster than those of a pure Round-Robin DNS.

• Journal of KIISE:Software and Applications
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• v.35 no.9
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• pp.538-546
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• 2008

It has limits that system administrator deals with many problems occurred in systems because computing environments are increasingly complex. It is issued that systems have an ability to recognize system's situations and adapt them by itself in order to resolve these limits. But it requires much experiences and knowledge to build the Self-Adaptive System. The difficulty that builds the Self-Adaptive System has been problems. This paper proposes a technique that generates automatically the codes of the Self-Adaptive System in order to make the system to be built more easily. This Self-Adaptive System resolves partially the problems about ineffectiveness of the exceeded usage of the system resource that was previous research's problem and incorrect operation that is occurred by external factors such as virus. In this paper, we applied the proposed approach to the file transfer module that is in the video conferencing system in order to evaluate it. We compared the length of the codes, the number of Classes that are created by the developers, and development time. We have confirmed this approach to have the effectiveness.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.213-229
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• 2005

Nuclides in radioactive wastes are assumed to be transported in the geosphere by groundwater and probably discharged into the biosphere. Quantitative evaluation of doses to human beings due to nuclide transport in the geosphere and through the various pathways in the biosphere is the final step of safety assessment of the radioactive waste repository. To calculate the flux to dose conversion factors (DCFs) for nuclides appearing at GBIs with their decay chains, a template ACBIO which is an AMBER case file based on mathematical model for the mass transfer coefficients between the compartments has been developed considering material balance among the compartments in biosphere and then implementing to AMBER, a general and flexible software tool that allows to build dynamic compartment models. An illustrative calculation with ACBIO is shown.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.140-145
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• 2007

The Lambda Networking is emerging to provide the high bandwidth stably for advanced applications such as a large file transfer in High Energy Physics and an Uncompressed HDTV streaming. The User Controlled LightPath(UCLP) is a software to facilitate the Lambda Networking. The UCLP is scalable as using Web Services to define and manage network resources. In this paper, we describe how we deployed the UCLP into KREONet2 and GLORIAD-KR. We also present that the original UCLP creates only a link-level APN due to a SONET technology. As employing a Virtual LAN (VLAN) of the layer2 technology in the UCLP, we can efficiently create a network-level APN.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.126-133
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• 2015

According to the traditional precedent, if a beneficiary who completed a provisional registration as a result of reservation of trade which is a fraudulent act, then assigned the right acquired by the provisional registration to the third party who has no information of the process, and let the third party complete an additional registration transfer the provisional registration, and if the third party completed the main registration on the foundation of the provisional registration, the beneficiary cannot be the other party of the litigation requesting for the cancellation of registration of the provisional registration. As the result, an apprehension that the duty to recovery of the beneficiary could easily be acquitted of a charge has existed. But, it is considered as desirable that the judicial decision judged that the court recognized the qualification of the defendant as appropriate at this case, with a different view from the precedent, and then the defendant can file the litigation against the beneficiary, requesting for cancellation of the reservation of trade which is a fraudulent act.

• Journal of Korean Library and Information Science Society
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• v.37 no.4
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• pp.371-389
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• 2006

The purpose of this study is to induce a librarian to construct databases lawfully and the user with a copyright and the fair use. Based on information from web sites, the domestic medical libraries(32) were investigated for analyzing how to deal with copyright problems. The results show that only 28% of the medical libraries provide users with information on copyright at their web site. The terminology used was different among libraries. 44.4% of the libraries use 'copyright law' and 33.3% 'copyright' The terminology appeared at the 'notice' menu and 'library guidance' menu. The detail part of copyright contents was shown at 'the data copy and transmission', 'full text DB use', 'thesis and dissertation service', 'FAX/file transfer', 'Image(Ariel)', and 'interlibrary loan'. In general, there was a necessity to the correct understanding of the copyright and fair use.

• Journal of the Korea Society of Computer and Information
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• v.10 no.5 s.37
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• pp.313-322
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• 2005

In this paper, we implement and verify performance monitor for parallel signal processing system, using DSP Starter Kit(DSK) of which the basic Processor is TMS302C6711 chip. The key ideas of this performance monitor is, using Real Time Data Exchange(RTDX) for the Purpose of real-time data transfer and function of DSP/BIOS, the ability to measure the Performance measure like DSP workload, memory usage, and bridge traffic. In the simulation, FFT, 2D FFT, Matrix Multiplication, and Fir Filter, which are widely used DSP algorithms, have been employed. Using performance monitor and Code Composer Studio from Texas Instrument(Tl) , the result has been recorded according to different frequencies, data sizes, and buffer sizes for a single wave file. The accuracy of our performance monitor has been verified by comparing those recorded results.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.519-521
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• 2011

NFC is enable communication between wireless davice within a distance of 10cm, one type of non-contanct short-range wireless communicaton using 13.56MHz frequency band. This is one type of RFID technology which include file transfer, contactless payment and RFID. NFC technology is standardized in 2003 already, it received much attention recently because NFC is announced full support in Android 2.3. And as APPLE is announced that have plan to monunt in iphone 5,mobile payment system is expected to change. Already SAMSUNG is launched NEXUS S mounted NFC chip and announced NFC chip will be mount GALAXY S2 LG Electronics is statemented NFC chip will be mount on smart phone that will realese this year. In this study, will announce about analysis for NFC technology and recently trend and used case.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1B
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• pp.1-12
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• 2002

In the multimedia CDMA mobile communication service, it is required to support various applications, such as voice, video, file transfer, e-mail, and Internet access, with guaranteed QoS. In the mixed traffic environment ,which consists of voice, stream data, and packet data, we analyze the network where preemptive priority is granted to delay-intolerant voice service and a buffer is offered to delay-tolerant stream data service. And, for best-effort packet data service, the access control by transmission permission probability is applied to obtain prominent throughput. To analyze the multimedia CDMA mobile communication system, we build a 2-dimensional markov chain model about prioritized-voice and stream data services and accomplish numerical analysis in combination with packet data traffic based on residual capacity equation.

• Journal of Broadcast Engineering
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• v.25 no.5
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• pp.655-664
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• 2020

Free viewpoint image synthesis technology is one of the important technologies in the MPEG-I (Immersive) standard. RVS (Reference View Synthesizer) developed by MPEG-I and in use in MPEG group is a DIBR (Depth Information-Based Rendering) program that generates an image at a virtual (intermediate) viewpoint from multiple viewpoints' inputs. RVS uses the mesh surface method based on computer graphics, and outperforms the pixel-based ones by 2.5dB or more compared to the previous pixel method. Even though its OpenGL version provides 10 times speed up over the non OpenGL based one, it still shows a non-real-time processing speed, i.e., 0.75 fps on the two 2k resolution input images. In this paper, we analyze the internal of RVS implementation and modify its structure, achieving 34 times speed up, therefore, real-time performance (22-26 fps), through the 3 key improvements: 1) the reuse of OpenGL buffers and texture objects 2) the parallelization of file I/O and OpenGL execution 3) the parallelization of GPU shader program and buffer transfer.