• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11A
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• pp.831-843
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• 2009

In this paper, we propose a new adaptive cooperation scheme with multi-relay nodes which achieves higher performance and spectral efficiency than that of some conventional cooperative schemes. The relay-selection is applied to choose the most potential relay among K ones. Afterward, the instantaneous signal-to-noise ratio (SNR) differences between S-D, S-R and R-D channels are considered for adaptive selection between the direct and the cooperation transmission strategy. In the proposed adaptive protocol, if the direct link is of high quality, the source will transmit to destination directly with all power consumption. Otherwise, the source broadcasts the signal with a lower power and requires the help of the chosen relay if it decodes correctly, else the source will transmit again with remaining power. Firstly, the spectral efficiency is derived by calculating the probability of each mode. Subsequently, the BER performance for the adaptive cooperation scheme is analyzed by considering each event that one of K relays is selected and then making the summation of all. Finally, the numerical results are presented to confirm the performance enhancement offered by the proposed schemes.

• Journal of the Korea Society of Computer and Information
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• v.6 no.3
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• pp.50-55
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• 2001

We review error resilience techniques for real-time video transport over unreliable networks. For error control on the source coding level, each decoder has to make provisions for error detection, resynchronization. and error concealment. and we review techniques suitable for that purpose. Further, techniques are discussed for intelligent processing of acknowledgment information by the coding control to adapt the source coder to the channel. We review and compare error tracking, error confinement. and reference picture selection techniques for channel-adaptive source coding. We review how feedback-based source codings are related with the precompressed video stored on a media server

• JOURNAL OF ELECTRICAL WORLD
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• no.12 s.144
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• pp.42-48
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• 1988

• JOURNAL OF ELECTRICAL WORLD
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• no.11 s.143
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• pp.27-32
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• 1988

• The Research Journal of the Costume Culture
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• v.6 no.4
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• pp.136-148
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• 1998

A apparel retail buyer played an important role in the market by providing apparel products for consumers and acting as an specialist who selected the vendor and decided the apparel product assortment. The purpose of this study was to investigate the relationships among the vendor selection criteria and information sources used by retailers and the satisfaction with store performance. A questionnaire was developed based on the previous studies and pretest. Data were collected from 237 retailers for women's apparel living in Pusan. Results indicated that they didn't significantly relate among the vendor selection criteria, information sources and the satisfaction with store performance except the harmony of buying products and existing products. Only the age and the buying experience showed significance in relation to demographics of apparel retailers among the vendor selection criteria, information sources and the satisfaction with store performance. The information source affected the vendor selection criteria was the street fashion, the apparel of entertainers, the other apparel buyer, and the owner of production. The findings had implications for retailers as well as for researchers.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.310-313
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• 2011

Broadcasting nature of wireless communications makes it possible to apply opportunistic network coding (OPNC) by overhearing transmitted packets from a source to sink nodes. However, it is difficult to apply network coding to the topology of multiple relay and sink nodes. We propose to use relay node selection, which finds a proper node for network coding since the OPNC alone in the topology of multiple relays and sink nodes cannot guarantee network coding gain. The proposed system is a novel combination of wireless network coding and relay selection, which is a key contribution of this paper. In this paper, with the consideration of channel state and potential network coding gain, we propose relay node selection techniques, and show performance gain over the conventional OPNC and a channel-based selection algorithm in terms of average system throughput.

• Journal of information and communication convergence engineering
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• v.12 no.1
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• pp.8-13
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• 2014

We consider the sensor selection problem in large sensor networks where the goal is to find the best set of sensors that maximizes application objectives. Since sensor selection typically involves a large number of sensors, a low complexity should be maintained for practical applications. We propose a geometry-based sensor selection algorithm that utilizes only the information of sensor locations. In particular, by observing that sensors clustered together tend to have redundant information, we theorize that the redundancy is inversely proportional to the distance between sensors and seek to minimize this redundancy by searching for a set of sensors with the maximum average distance. To further reduce the computational complexity, we perform an iterative sequential search without losing optimality. We apply the proposed algorithm to an acoustic sensor network for source localization, and demonstrate using simulations that the proposed algorithm yields significant improvements in the localization performance with respect to the randomly generated sets of sensors.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.6
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• pp.49-56
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• 2007

In this paper, the development of excitation light source is proposed for excitation light of the photodynamic therapy of cancer. Since the selection of the wavelength band of excitation light has an interrelation with fluorescence generation according to the selection of a photosensitizer. This study aims at designing and evaluating light source that can stably generate light with various kinds of wavelengths in order to make possible photodynamic diagnosis using a photosensitizer and diagnosis using auto-fluorescence. The light source device was a Xenon lamp and filter wheel, composed of an optical output control through iris and filters with several wavelength bands. It also makes the inducement of auto-fluorescence possible because it is designed to generate a wavelength band of 380-420nm, 430-480nm, 480-560nm. The transmission part of the light source was developed to enhance the efficiency of light transmission. To evaluate this light source device by KFDA#s technical reference, the characteristics of the light output and wavelength band were found.

• Journal of Haehwa Medicine
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• v.14 no.1
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• pp.15-22
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• 2005

Source : sources used by Qianghuo is Ostericum koreanum Maximowicz, Notopterygium incisum Ting and Notopterygium forbesii Boissier etc. in Korea and China. And we cirulate a Qianghuo dividing Nanqianghuo and Beiqianghuo. Thought source of Korea Qianghuo is different from china's we use a same name. And source of Beiqianghuo has not made clear yet. According to research accomplished 2002, we have to use Nanqianghuo producted at Jinbu in aspect of aspect. but, Beiqianghuo the outside form of Beiqianghuo similar to china so we think that we have to more make clear source of domestic Qianghuo, verify a source Beiqianghuo and re-establish about effects and functions of domestic Qianghuos. Culture : A term of culture is an nearly one year. so to product Qianghuo of good quality, we must plant directly in autumn or raise seedlings and transplant in spring. Processing : To protect turning to brown, Qianghuo are cirulate mostly as the original form without washing in water, To proteet crushing of Qianghuo when we cut off, Qianghuo were cut off after being soaked in water or steamed by heat. So when we wash and cut off, it has to be made processes which have no decreases of medical effects and be suggested a proper index which verify a medical effects. In summury, after harvesting Qianghuo the first washing $\rightarrow$ the first dry $\rightarrow$ selection $\rightarrow$ the second washing $\rightarrow$ the second dry $\rightarrow$ selection $\rightarrow$ cutting off $\rightarrow$ the third dry.

• The KIPS Transactions:PartD
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• v.15D no.6
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• pp.793-802
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• 2008

The development methods which utilize OSSs have been tried as new alternative to solve limits of the previous software developments such as the quality of software, and time and cost of developments. Especially, small and medium companies are suffering from difficulty in applying large-scale development methodology whenever they develop softwares. Therefore, in the current situation that demand for small-scale development methodology is increasing, the methods of utilizing OSSs can become an efficient way to save costs and reduce a development period. Accordingly, analysis of open-source is no fixed procedure or method to utilize open-source for software developments in the field. In this thesis, to solve such problems, we propose the procedures and methods for identifying and selecting suitable open-source, and effective methods for improvement and integration through least modification on the basis of synthesis of existing researches and experiences in development projects. For selection of OSSs, we did identify correct requirements for the software to be developed, investigate the open-source just matching with such requirements, draw a candidate index, establish assessment criteria, and the consequently present a method to select OSSs. And, we deduced the validity and improvement of each detailed activity from practical application to an actual project and assessment.