• Journal of Communications and Networks
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• 제16권3호
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• pp.280-292
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• 2014

This article presents a novel cooperative spectrum sharing (CSS) scheme. The primary transmitter transmits a complex Quadrature amplitude modulation (QAM) signal in the first phase, and CSS occurs in the second phase. The secondary transmitter with the largest forwarding channel gain among the nodes that successfully decode the primary signal in the first phase is selected for CSS. This selected node employs a pulse-amplitude modulation (PAM) signal for primary information message (IM) instead of the QAM signal, and it employs a modified PAM signal for the secondary IM. The proposed modified PAM signal depends on the amplitude of the primary PAM signal. This method results in no mutual interference and negligible primary interference constraint and allows a higher degree of exploitation of spatial diversity, thus enabling increase in secondary power to improve primary transmission. The outage performance is enhanced in both the primary and secondary systems. The critical region, in which the primary outage performance is enhanced with the proposed CSS scheme, can be adjusted and widened by varying either the modulation cooperation sharing factor or the number of secondary transmitters.

• 한국식품조리과학회지
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• 제22권2호
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• pp.250-257
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• 2006

Foodservice industry and distribution business could make mutual prpgress when they join forces in responding to environmental uncertainty in an efficient manner. The purpose of this study was to examine the relational characteristics of domestic food service businesses and distribution firms in conjunction with the distribution channels and ensuing conflicts between them, to present possible alternatives on and how they should communicate with each other to achieve a satisfactory result. The relational characteristics and ensuing conflicts of food service businesses and distribution firms appeared to be significantly characterized by incongruities of target, role and perception. The types of relational characteristics that were triggered by the disagreement of roles and perception combined to decrease the intensity of the relational commitment. A satisfactory transactional relationship served to ease their conflicts caused by perceptual disagreement, and the soos of conflicts that were rooted in the discord of roles and of perception that increased the degree of relational commitment. As for relational performance, relational commitment, satisfaction with distribution channel and satisfaction with suppliers allowed them to maintain their relationship on a long-term basis.

• 대한전자공학회논문지SP
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• 제40권5호
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• pp.322-331
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• 2003

HDTV(high-definition television)와 개인용 컴퓨터와 같은 다양한 매체의 발전에 따라 비월주사(interlaced scanning) 방식의 신호와 순차주사(progressive scanning) 방식의 신호 상호간의 변환에 대한 요구가 점점 늘어나고 있으며, 특히 비월주사 방식을 순차주사 방식으로 바꾸어주는 순차주사화(deinterlacing)가 활발히 연구되고 있다. 이러한 추세에 따라 본 논문에서는 부화소 단위의 움직임 정보를 이용한 순차주사화 알고리즘을 제안한다 이를 위해 움직임 추정과정에서 발생하는 부정확한 부화소 단위의 움직임 정보에 대하여 모델링하였다. 또한 집합이론(set-theory)에 근거하여 어떠한 사전 정보 없이 정규화값(regularization parameter)을 결정하여 영상들간의 부정확한 움직임에 의해 발생하는 에러를 최소화하였다. 본 논문에서 제안된 알고리즘은 실험을 통하여 검증 할 수 있었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권1호
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• pp.374-395
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• 2017

Users quite often experience volatile channel conditions which negatively influence multimedia transmission. HTTP adaptive streaming has emerged as a new promising technology where the video quality can be adjusted to variable network conditions. Nevertheless, the new technology does not remain without drawbacks. As it has been observed, multiple video players sharing the same network link have often problems with achieving good efficiency and stability of play-out due to a mutual interference and competition among video players. Our investigation indicates that there may be another cause for under-performance of the streamed video. In an emulated environment, we implemented three algorithms of adaptive video play-out based on bandwidth or buffer assessment. As we show, traffic generated by players employing the same or similar play-out strategies is positively correlated and synchronised (clustered), whereas traffic originated from different play-out strategies shows negative or no correlations. However, when some of the parameters of the play-out strategies are randomised, the correlation and synchronisation diminish what has a positive impact on the smoothness of the traffic and on the video quality perceived by end users. Our research shows that non-correlated traffic flows generated by play-out strategies improve efficiency and stability of streamed adaptive video.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권11호
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• pp.5610-5624
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• 2017

A novel scheme based on polarization modulation and the weighted fractional Fourier transform (PM-WFRFT) is proposed in this paper to enhance the physical layer security of dual-polarized satellite systems. This scheme utilizes the amplitude and phase of the carrier as information-bearing parameters to transmit the normal signal and conceals the confidential information in the carrier's polarization state (PS). After being processed by WFRFT, the characteristics of the transmit signal (including amplitude, phase and polarization state) vary randomly and in nearly Gaussian distribution. This makes the signal very difficult for an eavesdropper to recognize or capture. The WFRFT parameter is also encrypted by a pseudo-random sequence and updated in real time, which enhances its anti-interception performance. Furthermore, to prevent the polarization-based impairment to PM-WFRFT caused by depolarization in the wireless channel, two components of the polarized signal are transmitted respectively in two symbol periods; this prevents any mutual interference between the two orthogonally polarized components. Demodulation performance in the system was also assessed, then the proposed scheme was validated with a simulated dual-polarized satellite system.

• 안보군사학연구
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• 통권3호
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• pp.169-196
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• 2005

The point of Bush administraion’s foreign policy is to support the promotion and stability of Democracy in Iraq and counter terrorism and spread of WMD with his strong propulsive force caused by his reelection. In such an environment, there are his leadership, his team, himself, Kim Jung Il, and a new understanding of North Korea after September 11 as the effective factors of Bush administration’s policy toward Pyongyang. Bush administration’s foreign policy of North Korea also shows the process of North Korea’s nuclear weapon program and the future scenario of the Korean Peninsula with "the persistence of solving North Korea’s nuclear weapon program such as the method having done in Lybia", "the holding unconditional talks with Pyongyang, and "the continual concerns with human rights in North Korea." The purpose of Bush administration’s foreign policy of North Korea is to make North Korea do not support terrorism rather than remove the nuclear weapon in North Korea. The process of outlining South Korea’s policy toward North Korea must be considered for "national interest" with reasonable analyses not just hopes For this, South Korea must access systematically human rights of North Korea, prepare projects for a daring approach on North Korea, and strengthen South Korea’s defense ability toward North Korea with deep alliance with U.S and systematize the mutual understanding channel between U.S and South Korea. In conclusion, South Korea must try to get specific methods and practices about Bush administration’s foreign policy of North Korea with national wisdom

• 수면정신생리
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• 제8권1호
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• pp.67-71
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• 2001

Independent Component Analysis (ICA) is a blind source separation method using unsupervised learning and mutual information theory created in the late eighties and developed in the nineties. It has already succeeded in separating eye movement artifacts from human scalp EEG recording. Several characteristic sleep waves such as sleep spindle, K-complex, and positive occipital sharp transient of sleep (POSTS) can be recorded during sleep EEG recording. They are used as stage determining factors of sleep staging and might be reflections of unknown neural sources during sleep. We applied the ICA method to sleep EEG for sleep waves separation. Eighteen channel scalp longitudinal bipolar montage was used for the EEG recording. With the sampling rate of 256Hz, digital EEG data were converted into 18 by n matrix which was used as a original data matrix X. Independent source matrix U (18 by n) was obtained by independent component analysis method ($U=W{\timex}X$, where W is an 18 by 18 matrix obtained by ICA procedures). ICA was applied to the original EEG containing sleep spindle, K-complex, and POSTS. Among the 18 independent components, those containing characteristic shape of sleep waves could be identified. Each independent component was reconstructed into original montage by the product of inverse matrix of W (inv(W)) and U. The reconstructed EEG might be a separation of sleep waves without other components of original EEG matrix X. This result (might) demonstrates that characteristic sleep waves may be separated from original EEG of unknown mixed neural origins by the Independent Component Analysis (ICA) method.

• 품질경영학회지
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• 제21권1호
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• pp.1-10
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• 1993

The original purpose to introduce the system for quality certification by ISO 9000 series to our nation is basically promote the civilization interchanges among the various nations. we can't help regarding that the free trade is well performed to only a party and region to an agreement, but existed the possibility of being taken advantage of a means to the exclusive limiting import on the other regions. Under the considering the above situation, this study suggest that, the usuable policies of our domestic manufacturing corporations for acquiring the certification for the quality assurance of ISO 9000 series are as followings : 1) Using the civil and national diplomatic channel for the mutual assurance among the authorized agency of certification. 2) Gradually decreasing the difference between ISO 9000 and our nation in quality certification and solving the some problems as organizing the related research center. 3) In the post management of certified corporations, intentionally performing by using the authorized national agency from the ISO Headquarter and continuously reforming the related laws and regulations standardizing around the ISO series.

• 셀메드
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• 제13권6호
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• pp.8.1-8.4
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• 2023

The purpose of this study is to suggest that activities consisting of sympathy and gratitude are the way to healing. In our team's Hope World (希望世上), we changed the lyrics of GunbamTaryeong, which Koreans know the most, to create a healing Taryeong. The iterative refrain changed to "It's nice, it's hope, it's a good world for everyone." "The Wind Blows, Spring Has Come, The Moon Is Bright" will be the beginning of each chapter in GunbamTaryeong. It looks like a bright lyric, but it also shows both sides. All members participated in changing the lyrics, harmonizing the lyrics and rhythm, preparing props, playing musical instruments, and exciting performances. Therefore, it can be said that it is the story of healing where everyone is together. The song of Hope World is a real Taryeong that heals those who plan together, sing together, play musical instruments together. It's a "hope-Taryeong (希望打令)" who dreams of a "everyone good world." It's a Taryeong that lingers in my mouth and comes to mind. In this way, activities consisting of mutual cooperation and love doubled gratitude and sympathy for each other, and we think healing was achieved in the process. In this study, we suggest that sympathy and gratitude are perhaps the first steps towards healing. The Hope World Song (希望世上歌) is available on our channel YouTube (https://youtu.be/hgPiD4g2-iM).

• Nuclear Engineering and Technology
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• 제55권7호
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• pp.2432-2437
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• 2023

Methodology for suppressing or recovering the distorted spectra, which may occur due to mutual non-uniformity and nonlinear response when a multi-detector is simultaneously operated for gamma spectroscopy, is presented with respect to its applicability to stabilization of spectra having the non-identical feature using modified full spectrum reallocation method. The modified full-spectrum reallocation method is extended to provide multiple coefficients that describe the gain drift for multi-division of the spectrum and they were incorporated into an optimization process utilizing a random sampling algorithm. Significant performance improvements were observed with the use of multiple coefficients for solving partial peak dislocation. In this study, our achievements to confirm the stabilization of spectrum having differences in moments and modify the full spectrum reallocation method provide the feasibility of the method and ways to minimize the implication of the non-linear responses normally associated with inherent characteristics of the detector system. We believe that this study will not only simplify the calibration process by using an identical response curve but will also contribute to simplifying data pre-processing for various studies as all spectra can be stabilized with identical channel widths and numbers.