• Journal of the Korean Society of Radiology
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• v.6 no.3
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• pp.217-226
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• 2012

This study examines image quality of medical image after compression using JPEG2000 for AAPM CT Performance Phantom in PACS. The compressed images of 15:1 showed change of 1.93% and 0.81% in the CT number of water and the slice thickness, respectively, compared to the original images. The variation of the uniformity did not give a correlation for each measured area. In noise measurements at compressions of 10:1 and 15:1, changes of 1.47% to 10.99% were observed, respectively. The noise showed incremation tendency as increasing over the compression ratio 15:1, and the noise of 81.68% was measured at a compression of 40:1. CT number, uniformity, slice thickness, spatial resolution and contrast resolution for the compressed images were slightly changed by increasing the compression ratio. However, the noise was seriously changed relatively at the compressed images. Thus the noise was a important factor to determine the compression ration. A compression ratio of 10:1 for the AAPM CT Performance Phantom image was appropriate and could be applied to diagnostic images.

• Journal of Korean Library and Information Science Society
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• v.32 no.2
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• pp.239-267
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• 2001

The reading camp program for mutual reading activities between reader`s advisers and readers which has been played four times in 2000 shows the reaction to reading activities among them as follows. $\circled1$ All of reader`s advisers and readers took an active part in the reading camp program and reader's advisers were more active. $\circled2$ All of participants of the reading camp was satisfied by all of the reading program and especially leaders were affected by daily life of reader`s advisers. $\circled3$ All of participants had an opportunity of reflections on his reading activities and leader`s advisers established their sense of life and sense of values in more affirmative. The reading camp program helped participant to enhance his reading life very much and yet reader`s advisers acquired something more than readers did especially.

• Journal of Korean Society for Quality Management
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• v.31 no.4
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• pp.184-193
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• 2003

PL has been developed centering around England and America. Recently many countries are introducing PL system changing the world a single economic bloc based on the rapid development of Technology and Economy. This paper is studied with related literatures and theses, organizational consulting cases within the framework of the firm as the central operating bodies of PL system. In the past, Some papers about System Integration which was operated as a same Certificate System and enacted in a single organization, was studied and presented. But most of papers was a theoretical study related model and conception. In this situation Government supports PSMS of a single system at government expense to 100­200 companies for improving organizational confrontation ability of PL this year. This paper proposed a design and effect of Integration system model based on the analysis of ISO 9001：2000, KS, PSMS and ISO 14001. The integrated system has the following three distinctions. Firstly, KS is a national establishment, national leading certification and forcing standard. Secondly, ISO 9001：2000 and ISO 14001 are an international organization's establishment, non­official certification and optional standard. Finally, PSMS isn't a national law and forcing matter. And it isn't the concept of certification but the operational system by itself. Also if a lawsuit by defect is happened, it is very dangerous. This paper, which is integrated by four management systems and has many consulting cases, is the first in this department and is different from others. Also If people has the basic knowledge about management system, they can directly connect it to the organizational system according to this paper's guidance. It is very good result in this study because the law of PL is executed now.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.327-330
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• 2001

CDMA2000 1x 기반의 무선 인터넷 서비스가 가능해짐에 따라 무선 멀티 미디어 서비스에 대한 수요가 점점 늘어나고 있다. 화상 전화나 VOD 서비스와 같은 실시간 멀티 미디어 서비스에 사용되는 UDP는 현재의 유선과 무선이 혼합된 망에서는 패킷 전송 주기와 패킷의 크기에 따라 매우 다른 성능을 보여준다. 무선 구간에서 전송 효율을 높이기 위해서는 대역폭과 패킷손실률 그리고 채널의 타임슬롯 시간을 고려해 야 한다. 본 논문에서는 CDMA2000 1x 망에서 망 측정을 통하여 실시간 멀티미디어 전송에 적합한 QoS 인자를 추출하여 이를 개선 향상을 위해서 하고 실시간 멀티 미디어 서비스를 위한 대안을 제시하였다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.1
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• pp.105-113
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• 2005

I investigate whether the efficient ratios used as the proxies of the agency costs maintained by Ang et al.(2000) is significant. Utilizing a sample of 77 manufacturing companies listed on the KOSDAQ from the TS2000 of the KSDA, The results are as follows. Agency costs are found to be decreasing with the ownership share of controlling shareholders and accounting performance becomes higher. But firm value measured by Tobin's Q ratio becomes lower according as the ownership of the controlling shareholders increases. If agency costs decrease in proportion to controlling shareholder's share, firm value should be higher according to the agency theory by Jensen and Meckling(I976). But the results of the empirical test of this study are inconsistent with Jensen and Meckling's(1976). Therefore the following study on the more useful proxies stand for agency costs should be needed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.2A
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• pp.147-156
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• 2004

This paper presents an implementation and performance analysis of an access channel decoder which exploits a diversity gain due to the independent magnitude of received signals energy at each of antenna elements of a smart antenna BTS (Base-station Transceiver Subsystem) operating in CDMA2000 1X signal environment. Proposed access channel decoder consists of a searcher supporting 4 fingers, Walsh demodulator, and demodulator controller. They have been implemented with 5 of 1 million-gate FPGA's (Field Programmable Gate Array) Altera's APEX EP20K1000EBC652 and TMS320C6203 DSP (digital signal processing). The objective of the proposed access channel decoders is to enhance the data retrieval at co]1-site during the access period, for which the optimal weight vector of the smart antenna BTS is not available. Through experimental tests, we confirmed that the proposed access channel decoder exploitng the diversity technique outperforms the conventional one, which is based on a single antenna channel, in terms of detection probability of access probe, access channel failure probability, and $E_{b/}$ $N_{o}$ in Walsh demodulator.r.r.

• The Bulletin of The Korean Astronomical Society
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• v.25 no.2
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• pp.82-82
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• 2000

• Journal of the Korean earth science society
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• v.23 no.1
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• pp.105-111
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• 2002

The observation of the new biotite isograd (chlorite + chloritoid = andalusite + biotite) in the Mungyong coal field requires the modification of Harte and Hudson's (1979) metapelite grid which eliminates the stability field of staurolite + cordierite assemblages. The newly proposed metapelite grid by Ahn and Nakamura (2000) can define more properly the isograd reaction observed from nature. We discuss first topological interrelations between synthetic system (FASHO-, KFASHO-, KFMASH system) on an isobaric section at 2kbar, where phase relations are well constrained. The following discussion is concentrated on the topological relations between stable reactions. At the last, we discuss the petrogenetic significance of the Ahn's petrogenetic grid compared with theoretically computed grids. Ahn's petrogenetic grid is consistent with synthetic and natural system, and is one of the excellent example of KFMASH approximation in metapelite.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.17-20
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• 2000

Over the years of decades, the memory technology has progressed a long, marble way. As we have evidenced from the Intel’s 1Kb DRAM in 1970 to the Gigabit era of 2000’s, the road further ahead towards the Terabit era will be unfolded. The technology once perceived inconceivable is in realization today, and similarly roadblocks as we know of today may become trivial issues for tomorrow. For the inquiring mind, the question is how the “puzzle” of tomorrow’s memory technology is pieced-in today. The process will take place both in evolutionary and revolutionary ways. Among these, note-worthy are the changes in DRAM architecture and the cell process technology. In this paper, some technical approaches will be discussed to bring these aspects into a general overview and a perspective with possibilities for the new memory technology will be presented.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.92-97
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• 2000

An AMR(Adaptive Multi-Rate) speech coding algorithm has been adopted as a standard speech codec for IMT-2000. It is based on the algebraic CELP, and consists of eight speech coding modes having the bit rate from 4.75 kbit/s to 12.2 kbit/s. It also contains the VAD(Voice Activity Detector), SCR (Source Controlled Rate) operation, and error concealment scheme for robustness in a radio channel. The bit rate of AMR is changed on a frame basis depending on the channel condition. In this paper, we introduced AMR speech coding algorithm and performed the real-time implementation using TMS320C6201, i.e., a Texas Instrument's fixed-point DSP. With the ANSI C source code released from ETSI and 3GPP, we convert and optimize the program to make it run in real time using the C compiler and assembly language. It is verified that the decoded result of the implemented speech codec on the DSP is identical with the PC simulation result using ANSI C code for test sequences. Also, actual sound input/output test using microphone and speaker demonstrates its proper real-time operation without distortions or delays.