• 제목/요약/키워드: Information access

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An Improved Contention Access Mechanism for FPRP to Increase Throughput

  • Yang, Qi;Zhuang, Yuxiang;Shi, Jianghong
    • ETRI Journal
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    • 제35권1호
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    • pp.58-68
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    • 2013
  • Five-phase reservation protocol (FPRP) is a contention-based media access control protocol for wireless ad hoc networks. FPRP uses a five-phase reservation process to establish slot assignments based on time division multiple access. It allows a node to reserve only one slot in an information frame. Once a node has reserved a slot, it will cease contending for other slots. As a result, there may be less contending nodes in the remaining slots, so the time slots in an information frame are not fully used by FPRP. To improve time slot utilization, this paper proposes an improved pseudo-Bayesian algorithm, based on which an improved contention access mechanism for FPRP is proposed, in which nodes are allowed to contend for more than one slot in a reservation frame according to a certain probability/priority. Simulation results indicate that the proposed mechanism performs better than FPRP in time slot utilization and hence the network throughput under various scenarios.

A Distributed Medium Access Control Protocol for Cognitive Radio Ad Hoc Networks

  • Joshi, Gyanendra Prasad;Kim, Sung Won;Kim, Changsu;Nam, Seung Yeob
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권1호
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    • pp.331-343
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    • 2015
  • We propose a distributed medium access control protocol for cognitive radio networks to opportunistically utilize multiple channels. Under the proposed protocol, cognitive radio nodes forecast and rank channel availability observing primary users' activities on the channels for a period of time by time series analyzing using smoothing models for seasonal data by Winters' method. The proposed approach protects primary users, mitigates channel access delay, and increases network performance. We analyze the optimal time to sense channels to avoid conflict with the primary users. We simulate and compare the proposed protocol with the existing protocol. The results show that the proposed approach utilizes channels more efficiently.

Adaptively Secure Anonymous Identity-based Broadcast Encryption for Data Access Control in Cloud Storage Service

  • Chen, Liqing;Li, Jiguo;Zhang, Yichen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제13권3호
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    • pp.1523-1545
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    • 2019
  • Cloud computing is now a widespread and economical option when data owners need to outsource or share their data. Designing secure and efficient data access control mechanism is one of the most challenging issues in cloud storage service. Anonymous broadcast encryption is a promising solution for its advantages in the respects of computation cost and communication overload. We bring forward an efficient anonymous identity-based broadcast encryption construction combined its application to the data access control mechanism in cloud storage service. The lengths for public parameters, user private key and ciphertext in the proposed scheme are all constant. Compared with the existing schemes, in terms of encrypting and decrypting computation cost, the construction of our scheme is more efficient. Furthermore, the proposed scheme is proved to achieve adaptive security against chosen-ciphertext attack adversaries in the standard model. Therefore, the proposed scheme is feasible for the system of data access control in cloud storage service.

Biometric System(fingerprint Reader)을 이용한 Access Control System 구현에 관한 연구 (The implementation of Access Control System using Biometric System)

  • 김광환;김영길
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2003년도 춘계종합학술대회
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    • pp.439-442
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    • 2003
  • 본 연구에서는 생체인식(Biometric)을 이용하여 Access Control System을 구현하였다. Biometric 는 생체 인식 또는 생체 측정학으로 사람의 생체적, 행동적 특성을 이용하여 개인을 식별하는 학문 또는 기술이다. Access Control System은 개인을 식별 출입과 근태, 개인 관리, 보안 둥에 사용하는 System으로 Biometric System과 접목으로 편리성과 보안성에서 탁월한 효과를 발휘할 수 있다. 본 연구에서 제안한 시스템은 기존의 RF Card System에 Wiegand(Data format) Signal 출력으로 기존 RF Card Reader대신 Access Control (Security) System을 구성할 수 있도록 설계되었고 컴퓨터와 RS-232, RS-422 또는 Tcp/Ip로 구성되어 Software상에서 임베이디드 System을 Control 할 수 있게 되어 있다.

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생체인식 시스템을 이용한 Access Control System 구현에 관한 연구 (The implementation of Access Control System using Biometric System)

  • 김광환;김영길
    • 한국정보통신학회논문지
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    • 제8권2호
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    • pp.494-498
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    • 2004
  • 본 연구에서는 생체인식(Biometric)을 이용하여 Access Control System을 구현하였다. Biometrics는 생체인식 또는 생체 측정학으로 사람의 생체적, 행동적 특성을 이용하여 개인을 식별하는 학문 또는 기술이다. Access Control System은 개인을 식별 출입과 근태, 개인 관리, 보안 등에 사용하는 System으로 Biometric System과 접목으로 편리성과 보안성에서 탁월한 효과을 발휘할 수 있다. 본 연구에서 제안한 시스템은 기존의 RF Card System에 Wiegand(Data format) Signal 출력으로 기존 RF Card Reader대신 Access Control (Security) System을 구성할 수 있도록 설계되었고 컴퓨터와 RS-232, RS-422 또는 TCP/IP 로 구성되어 Software상에서 임베이디드 System을 Control 할 수 있게 되어 있다.

미래도서관에서의 소장(ownership)과 접근(access)의 문제 (Problems on ownership and access in future librarty)

  • 양재한
    • 한국도서관정보학회지
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    • 제25권
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    • pp.19-50
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    • 1996
  • The purpose of this paper is to study on ownership and access in future library. For this purpose, this is criticized about recognition regarding future library of Library and Information Science researchers in Korea. And, this is reviewed the present stages of collection development and a role of future books, future libraries and future librarians in Korea. The result of this study is known unrealistic reality analysis and forecast surrounding future library discourse and at the same time that following Western model is not fit for future library in Korea. This study is proposed resolving of problems to access based on physical collection in future library.

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디지털 격차 : 대전지역 초등학생을 중심으로 (Digital Divide: Elementary school students in Taejon, Korea)

  • 최종인;오광록;박현아
    • 한국기술혁신학회:학술대회논문집
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    • 한국기술혁신학회 2000년도 추계 학술대회(The 2000 Autumn Conference of korea Technology Inovation Society)(한국기술혁신학회)
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    • pp.5-24
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    • 2000
  • Access to computers and the internet and the ability to effectively use this technology are becoming increasingly important for full participation in Korea′s economic, education, and social life. In recent years, access to computers and internet has exploded. Unfortunately, there is strong evidence of "digital divide"-gap between those individual and communities that have access to these information technology and those who don′t. This research focus on the elementary school students in Taejon, Korea. We found that there is digital divide among children and also different result between access to information technology and use of contents to information technology.

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

  • 이정미;황혜경
    • 한국비블리아학회지
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    • 제32권4호
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    • pp.47-66
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    • 2021
  • 본 연구는 오픈액세스 출판지원 서비스 플랫폼인 AccessON 학술지 리포지터리 인터페이스 중 관리자 인터페이스의 사용성 평가를 통해 오픈액세스 출판지원 서비스 플랫폼의 개선방안을 모색하고자 하는 연구이다. 인터페이스의 사용경험 응답 수집, 이를 통한 이슈 및 개선점 도출, 타 오픈액세스 출판지원 서비스 플랫폼을 위한 제안사항 분석 및 도출이라는 세 가지 연구 질문에 대한 응답을 위해 오픈액세스 출판 및 사용성 평가에 관련된 각종 문헌과 사례같은 선행연구를 검토하였으며, 설문조사와 포커스그룹 인터뷰를 통해 관리자 인터페이스 사용경험에 대한 응답을 수집하였다. 이를 종합하여 AccessON 학술지 리포지터리 인터페이스의 사용성 평가 결과를 각종 수치정보를 통해 제시할 수 있었다. 사용성 평가의 결과는 AccessON 학술지 리포지터리 관리자 인터페이스의 이슈 및 개선점을 제안가능하게 하였으며 최종적으로 이후 개발될 오픈액세스 학술출판지원 서비스 플랫폼을 위한 제안사항을 도출할 수 있었다.

PPP를 사용한 BlueTooth LAN접근 프로파일의 구현 방법 (Implementation of BlueTooth LAN Access Profile Using PPP)

  • 박우현;유인태
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2001년도 봄 학술발표논문집 Vol.28 No.1 (A)
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    • pp.154-156
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    • 2001
  • 본 논문에서는 현재 무선으로의 전환에서 중요한 기술인 BlueTooth를 사용한 LAN access point에 대하여 연구하여 다른 모든 무선으로의 대안들 보다 블루투스가 우월함을 소개한다. 이를 위하여 블루투스 프로토콜 전체 스택에 대해서 살펴보고 Axis의 Linux LAN Access Profile을 응용하여 Windows로의 이식을 고안하고 이에 필요한 함수들을 제안한다. 또한 Windows로의 이식에 있어서 필요한 기술인 NDIS를 살펴본다. 아울러 Profile을 응용한 LAN Access Profile을 구현한 LAN Access Point를 구현한 후, 결론에서 불루투스 차기버전으로의 이식 문제와 RTOS로의 이식을 고려해본다.

Assessment and Support Measures of Academic Journals in the National Open Access Platform AccessON

  • Hyekyong Hwang;Eun Jee Lee;Wan Jong Kim;Jin Ho Park
    • Journal of Information Science Theory and Practice
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    • 제12권3호
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    • pp.75-88
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    • 2024
  • This study aims to assess the maturity of Korean open access (OA) journals using the OA infrastructure provided by the Korea Institute of Science and Technology Information, and develop necessary strategies for future improvement. The assessment model consists of three dimensions, 12 items, and 24 sub-items. The importance of the three dimensions (A: OA policy establishment and disclosure, B: OA sustainability, and C: Journal openness quality) was differentiated by the Analytic Hierarchy Process, and the maturity stages were divided into five levels (Entry, Growth1, Growth2, Maturity1, and Maturity2). The assessment was carried out twice for 100 academic journals. The results indicated that the proportion of journals at or above the Growth1 level increased by 11% to reach 83% during the second assessment phase, which could be owing to the learnings of the first assessment. Following expert consultations on the assessment results, three support measures were identified to activate OA. The first includes OA promotion and education activities, which involve creating standard regulations and guidelines, and advancing educational activities for societies that are either preparing for or currently implementing OA. The second involves providing support for technical aspects, such as identifiers, XMLization, and copyright management, through peer review and OA publishing platforms. The third includes collaborative activities to enhance journal evaluations and the recognition criteria for researchers' achievements in OA journals, and fostering cooperation with national and research and development institutions for financial support.