• Title/Summary/Keyword: 액세스

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Design of Radio Interface Protocols for Broadband CDMA Wireless Local Loop and Access Channel Performance Analysis (광대역 CDMA WLL 무선 프로토콜 설계 및 액세스채널의 성능분석)

  • 김영태;박기식;조정호;김광현;이태훈
    • Journal of Korea Multimedia Society
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    • v.2 no.1
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    • pp.47-58
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    • 1999
  • In this paper, we design the radio interface protocols of wideband Wireless Local Loop(WLL) that uses wideband Code Division Multiple Access(CDMA), and propose the random access procedures on access channel and analyze the performance of the channel. The structure of radio interface protocols are designed by three modular parts to meet the requirements of IMT-2000 : radio resource controlling part that depends on the radio resources, connection controlling part that is independent of the radio resources, and application part that supports the interface between different parts and user terminals. In addition, we propose the random access procedures on access channel and analyze the performance of the channel. We assume that both near-far effect and shadow fading can be compensated by open loop power control. We observe that the number of access probes(delay) depend on the initial mobile transmission power and power increment, and the poor estimation of initial mobile transmission power might increase the average number of access probes.

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A Study on the Operational Model for Open Access Based e-Journal Subscription of University Library (대학도서관의 오픈액세스 기반 전자저널 구독을 위한 운영모델 연구)

  • Kang, Jeong Won;Kim, Hyun-Hee
    • Journal of the Korean Society for information Management
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    • v.35 no.3
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    • pp.123-145
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    • 2018
  • In this study, we investigated the problems of existing e-journal subscriptions caused by open access of e-journals faced by university libraries. To solve these problems, we proposed an operational model for open access based subscription. The proposed operational model, which adapts the four concepts of subscription model, system, policy, and operation interpreted according to reality, applies open access on the premise of rational subscription of electronic journals. The proposed operational model was constructed based on national support, comprehensive operation, open access based model, and cooperation system. In particular, it emphasized the need for stable and continuous access to scholarly information through national support policy. The proposed operational model can be used as a basic data for the realization and research of open access in the domestic environment.

Improvement of the access channel algorithm in the CDMA2000 system (CDMA2000시스템에 있어서 액세스채널 알고리즘 개선)

  • Lee Kwang jai;Chun Jong hun;Park Jong an
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.3B
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    • pp.138-143
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    • 2005
  • This paper aims to optimize an access probe algorithm for the CDMA 2000 system. The incremental value of PWR_STEP increases as NUM_STEP as 1dBm±0.2 for access probe of the area with good receiving sensitivity when the mobile station transmits via access channel and does not receive any ACK message. However, for the area with weak receiving sensitivity, according to the algorithm of open-loop power control, the transmitting power amplifier becomes saturated and PWR_STEP incremental value keeps performing access probe to 0dBm±0.2. Therefore interference and battery consumption increases according to the transmission of the mobile station. We have optimized the access probe algorithm according to the receiving sensitivity. We transmit the incremental value of access probe power, with delaying as much RT slot value as indicated by IS-95C standard in case of good receiving sensitivity and with delaying RT+l slot value in case of weak receiving sensitivity. Simulation results showed that the proposed algorithm contributes to decrease of the interference and battery consumption according to the transmitting power of the mobile station and improves the call duration.

Domain Analysis on the Field of Open Access by Co-Word Analysis (동시출현단어 분석 기반 오픈 액세스 분야 지적구조에 관한 연구)

  • Seo, SunKyung;Chung, EunKyung
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.24 no.1
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    • pp.207-228
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    • 2013
  • Due to the advance of scholarly communication, the field of open access has been studied over the last decade. The purpose of this study is to analyze and demonstrate the field of open access via co-word analysis. The data set was collected from Web of Science citation database during the period from January 1998 to July 2012 using the Topic category. A total of 479 journal articles were retrieved and 8,643 noun keywords were extracted from the titles and abstracts. In order to achieve the purpose of this study, network analysis, clustering analysis and multidimensional scaling mapping were used to examine the domain and the sub-domains of open access field. 18 clusters in the network analysis are recognized and 4 clusters are shown in the map of multidimensional scaling. In addition, the centrality analysis in the weighted networks was used to explore the significant keywords in this field. The results of this study are expected to demonstrate and guide the intellectual structure and new approaches of open access field.

A Study on the Difference among Journal Publisher and among the Academic Disciplines of Factors Influencing the Adoption of Open Access (오픈 액세스 수용에 영향을 미치는 요인의 학술지 발행기관별 차이 및 학문분야별 차이에 관한 연구)

  • Ko, Young-Man;Kim, Bo-Ae;Park, Tae-Sik;Lee, Kil-Shin
    • Journal of the Korean Society for Library and Information Science
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    • v.43 no.4
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    • pp.431-449
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    • 2009
  • The purpose of this study was to examine the differences among journal publishers and among academic disciplines on factors influencing the adoption of open access. Through the analysis of previous studies, we identified five such factors: journal publishers' attitudes, ability, confidence, social influence and material resources available for open access. The results show that a significant difference among journal publishers from social influence factor. This result implies that efforts toward journal subscribers to have a positive attitude and material resources are important factors for journal publishers. There was a significant difference among academic disciplines in terms of journal publishers' attitudes and ability factors. The findings of this result imply that academic journals need to share more information about open access and that priority should be given to journals that have the ability to influence the adoption of open access.

File Access Pattern Collection Scheme based on Repetitiveness (반복성을 고려한 파일 액세스 패턴 수집 기법)

  • Hwnag-Bo, Jun-Hyoung;Seok, Seong-U;Seo, Dae-Hwa
    • Journal of KIISE:Computer Systems and Theory
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    • v.28 no.12
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    • pp.674-684
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    • 2001
  • This paper presents the SIC(Size-Interval-Count) prefetching scheme that can record the file access patterns of applications within a relatively small space of memory based on the repetitiveness of the file access patterns. Several knowledge-based prefetching methods were recently introduced, which includes high correctness in predicting future accesses of applications. They records the access patterns of applications and uses recorded access pattern information to predict which blocks will be requested next. Yet, these methods require to much memory space. Accordingly, the proposed method then uses the recorded file access patterns, referred to as "SIC access pattern information", to correctly predict the future accesses of the applications. The proposed prefetching method improved the response time by about 40% compared to the general file system and showed remarkable memory efficiency compared to the previously knowledge-based prefetching methods.

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An Analysis on Current Research Funding and Open Access Status for Science and Technology Articles Published by S University Faculties (이공계 학술논문의 연구비 지원 및 오픈액세스 현황 분석:S대를 중심으로)

  • Shin, Eun-Ja
    • Journal of Information Management
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    • v.41 no.4
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    • pp.1-21
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    • 2010
  • To identify current status of research funding and open access, this study analyzed the data available in science and technology articles had been published by S university's faculty members. The study showed that 71% of the articles funded by their universities or other research sponsors, whereas very few of articles have been self-archived for open access. So, government-sponsored research outputs could not be found in search engine Google Scholar. In developed countries, researchers who have received grants by the public or private sponsors should not only publish articles on scholarly journals but also deposit their digital research outputs in the repositories. Therefore, it is advisable for Korea research sponsors to strengthen and carry out open access mandate related laws. It is very important for universities as well as for their faculties that published articles' impact can be maximized by enabling open access. So, universities may as well construct their repositories and collect the contents with enthusiasm.

Case Study of Usability Evaluation and Improvement Plan for Open Access Academic Publishing Support Interface (오픈액세스 학술출판 지원 인터페이스 사용성 평가 및 개선안 사례 연구)

  • Lee, Jeong-Mee;Hwang, Hyekyong
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.32 no.4
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    • pp.47-66
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    • 2021
  • The goal of this study is to find ways to improve the open access publication support service platform through the usability evaluation of the publishing manager interface among the AccessON journal repository interfaces, which is an open access publication support service platform. Various documents and cases related to open access publishing and usability evaluation in order to answer three research questions: collection of user experience responses of interface, extraction of issues and improvement points, and analysis and derivation of suggestions for other open access publication support service platforms. Responses to the experience of using the publishing manager interface were collected through surveys and focus group interviews. Combining this, it was possible to present the results of the usability evaluation of the AccessON journal repository interface through various numerical information. The results of the usability evaluation made it possible to propose issues and improvements to the AccessON journal repository manager interface, and finally, it was possible to derive suggestions for the open access academic publishing support service platform to be developed later.

The Current State of Foreign Transition to Open Access Journal Publishing in the Field of HSS (해외 인문사회과학 학술지 오픈액세스 전환 동향 연구)

  • Lee, Jae Yun;Joung, Kyoung Hee
    • Journal of the Korean Society for information Management
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    • v.37 no.3
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    • pp.301-326
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    • 2020
  • This study analyzed recent cases of transition to open access(OA) journals in humanities and social sciences(HSS) in foreign countries to find a way to transition to OA journals in Korea. Ling OA and UP led by researchers, OLH and KU led by libraries, S2O led by publishers and L+F model led by funders and libraries were analyzed. Programs by national funding agencies such as the Norwegian Research Council, Canada Social Sciences and Humanities Research Council, Austrian Science Fund, and Swiss Academy of Humanities and Social Sciences were also reviewed. Based on the results of the analyses, this study suggests for transition in Korean HSS field as follows; 1) transitions to open access journals in HSS should be supported at national level 2) the stakeholder in scholarly communications such as the nation, universities, libraries, research funders, scholarly societies etc has their own role in the transition but funders and libraries are the most important in financial support for open access publishing 3) but the financial support for the first stage of the transition should be done at national level 4) and open access journal publishing consortium comprised of libraries and information service institutions in the public sector such as KERIS, KISTI and the national library should be established 5) non commercial publishing platforms for scholarly societies should be developed and distributed.

A New Coeff-Token Decoding Method based on the Reconstructed Variable Length Code Table (가변길이 부호어 테이블의 재구성을 통한 효율적인 Coeff-Token 복호화 방식)

  • Moon, Yong-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.3C
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    • pp.249-255
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    • 2007
  • In general, a large amount of the memory accesses are required for the CAVLC decoding in H.264/AVC. It is a serious problem for the applications such as a DMB and videophone services because the considerable power is consumed for accessing the memory. In order to solve this problem, we propose an efficient decoding method for the coeff-token which is one of the syntax elements of CAVLC. In this paper, the variable length code table is re-designed with the new codewords which are defined by investigating the architecture of the conventional codeword for the coeff_token element. A new coeff_token decoding method is developed based on the suggested table. The simulation results show that the proposed algorithm achieves an approximately 85% memory access saving without video-quality degradation, compared to the conventional CAVLC decoding.