• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권5호
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• pp.2015-2028
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• 2016

In this paper, we propose a sum transmission rate maximization based cooperative spectrum sharing protocol with quality-of-service (QoS) support for both of the primary and secondary systems, which exploits the situation when the primary system experiences a weak channel. The secondary transmitter ST_b which provides the best performance for the primary and secondary systems is selected to forward the primary signal. Specifically, ST_b helps the primary system achieve the target rate by using a fraction of its power to forward the primary signal. As a reward, it can gain spectrum access by using the remaining power to transmit its own signal. We study the secondary user selection and optimal power allocation such that the sum transmission rate of primary and secondary systems is maximized, while the QoS of both primary and secondary systems can be guaranteed. Simulation results demonstrate the efficiency of the proposed spectrum sharing protocol and its benefit to both primary and secondary systems.

• Journal of Communications and Networks
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• 제16권2호
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• pp.140-145
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• 2014

In this paper, we propose an anti-interference cooperative spectrum sharing strategy for cognitive system, in which a secondary system can operate on the same spectrum of a primary system. Specifically, the primary system leases a fraction of its transmission time to the secondary system in exchange for cooperation to achieve the target rate. To gain access to the spectrum of the primary system, the secondary system needs to allocate a fraction of bandwidth to help forward the primary signal. As a reward, the secondary system can use the remaining bandwidth to transmit its own signal. The secondary system uses different bandwidth to transmit the primary and its own signal. Thus, there will be no interference felt at primary and secondary systems. We study the joint optimization of time and bandwidth allocation such that the transmission rate of the secondary system is maximized, while guaranteeing the primary system, as a higher priority, to achieve its target transmission rate. Numerical results show that the secondary system can gain significant improvement with the proposed strategy.

• 한국문헌정보학회지
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• 제33권1호
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• pp.145-160
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• 1999

학술정보는 1차자료와 2차자료의 2가지로 구분할 수 있다. 1차자료는 학술정보 그 자체이고 2차자료는 색인, 초록, 서지 등과 같은 1차자료를 찾아볼 수 있는 길잡이이다. 2차자료에 수록된 정기간행물의 중복된 점과 범위를 이전에 연구한 자료와 금번 조사한 자료를 비교 검토하였으며 문헌정보학분야 2차자료 Library and Information Science Abstract (LISA) : Library Literature (LL) : Information Science Abstract (ISA) 등 3가지의 주요 2차자료를 비교 분석한 결과 문헌정보학 관계 자료선정 및 장서개발 정책에 영향을 미칠 수 있음을 제시 하고있다.

• 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.

• 한국컴퓨터정보학회논문지
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• 제21권3호
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• pp.17-23
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• 2016

In this paper, we propose a model of the collaborative authoring tool and its implementation results. In the 'collaborative authoring and automatic distribution system,' users can create eBooks by using partial works (primary and edited sources) on the basis of copyright information registered by the primary author. The Collaborative Authoring Tool is a part of "the collaborative authoring and automatic distribution system" developed through research on "the development of key technologies of social work protection and content mashup tools" as an R&D project granted by the Korea Copyright Commission from 2013. In the collaborative authoring and automatic distribution system, authors of primary sources such as images, audio clips and video clips for eBooks can register them together with the copyright information; users can edit the primary sources to produce secondary sources and in turn register the secondary sources on the system; and users can create and distribute eBooks by using the sources registered in the system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권3호
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• pp.273-288
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• 2010

In this paper, we propose a cooperative multi-relay scheme for a secondary system to achieve spectrum access along with a primary system. In the primary network, a primary transmitter (PT) transmits the primary signal to a primary receiver (PR). In the secondary network, N secondary transmitter-receiver pairs (ST-SR) selected by a centralized control unit (CCU) are ready to assist the primary network. In particular, in the first time slot, PT broadcasts the primary signal to PR, which is also received by STs and SRs. At STs, the primary signal is regenerated and linearly combined with the secondary signal by assigning fractions of the available power to the primary and secondary signals respectively. The combined signal is then broadcasted by STs in a predetermined order. In order to achieve diversity gain, STs, SRs and PT will combine received replicas of the primary signal, using selection combining technique (SC). We derive the exact outage probability for the primary network as well as the secondary network. The simulation results are presented to verify the theoretical analyses.

• East Asian mathematical journal
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• 제29권1호
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• pp.101-107
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• 2013

We consider a cognitive network with a primary and a secondary channel. Primary users have higher priority on the usage of the primary channel, and secondary users are allowed to opportunistically access the primary channel at times when the channel is not occupied by primary users. The secondary channel is dedicated only to secondary users. An analytical model is presented to obtain the performance of an opportunistic spectrum access using both the primary and secondary channels, and is validated by simulations.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1429-1432
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• 2007

We fabricated white organic light emitting diodes(WOLED) having two complementary and three primary colors with emission layers of DPVBi / MADN : DCM2-0.5% and DPVBi / $Alq_3$ / MADN : DCM2-1.5%, respectively. WOLED using three primary colors shows broad electroluminescence including green emission peak at 510nm while optical properties of the two complementary WOLED was higher current efficiency of 6.2 cd/A than 4.9 cd/A of three primary color WOLED. The maximum luminescence of WOLED with two complimentary color was $15200cd/m^2$ along with luminous efficiency 6.2cd/A, as achieving stable white color coordinates for both of WOLEDs at (0.33 , 0.33) almost.

• 한국컴퓨터정보학회논문지
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• 제24권9호
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• pp.143-150
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• 2019

In recent years, interest in internet primary bank has increased in South Korea, and marketing strategies for the success of the bank are needed. The purpose of this study is to analyze the effect of bank choice attributes on satisfaction and behavioral intention of Internet primary bank users. A convenience sampling was used and a structural equation of AMOS 20.0 was used for hypothesis testing. The results of the study are as follows. First, information, transaction, and communication of the choice attributes have positive effects on satisfaction. Second, information, transaction, and communication of the choice attributes have positive effects on behavioral intention. Third, satisfaction has a positive effect on behavioral intention. The theoretical and practical implications and limitations of the research are presented in the conclusion.

• Acta Via Serica
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• 제3권2호
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• pp.151-160
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• 2018

There is a variety of opinions about the first translation activities within the Turkic Empire. It is widely believed that some Buddhist sutras were translated into the Turkic language in the period of Taspar Qagan (572-581). This theory is based on certain arguments: Some Turks practiced Buddhism, Buddhist monks translated sutras in the center of the Turkic Empire, Taspar brought sutras from China and had them translated, and the monarch of Northern Qi had a sutra translated and sent to Taspar. However, in my opinion, these arguments lack credibility. This article, which is based on primary Chinese sources, will question the likelihood of such translation activities having occurred. Some Chinese records for these claims exist: Da Tang Nei Dian Lu (大唐內典錄) and Xu Gao Seng Chuan (續高僧傳) by the Buddhist monk Jinagupta and the records of Hui Lin in Sui Shu (隋書) and Wen Xian Tong Kao (文獻通考). These are known as "primary sources." Secondary sources, namely contemporary history and language studies, such as those in books and articles, must be based on primary sources. It can be seen that claims relating to the first Turkic translation activities at the time of Taspar are mainly derived from secondary sources, and that the arguments in these secondary sources vary. Sometimes researchers make suppositions on the existence of information that is not referred to in primary sources. However, this is not normal practice. If a researcher relies on unknowns for the evidence of information existing, it can cause false information, ideas and anachronisms to be created. It is important that primary sources, such as the Chinese sources mentioned above, be translated correctly in language and history studies. If only a word is mistranslated, very different results may occur. Mistranslating or misinterpreting a primary source allows conclusions to be reached that are not supported by dissemination of information from primary sources. This can mislead experts and result in information that is not correct being considered as being true. As well as helping to prevent such misinterpretations occurring, another aim of this paper is to question the interpretations of the first Turkic translations in contemporary studies on history and language. The origin of such assessments will be explored and the validity of that information will be examined.