• Title/Summary/Keyword: Service link

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Philosophical and Theoretical Perspectives of Five Laws of Libraries and its Influence on the Library Profession: Issues and Challenges

  • Krishnamurthy, M.
    • Journal of the Korean Society for Library and Information Science
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    • v.45 no.4
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    • pp.271-286
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    • 2011
  • The role of information in knowledge society has changed. Library refers to information centre, which is actively involved information collection and promoting use of for the development of individual and society. Modern libraries are the centres of interaction for all interested in accessing information and in participating in the marathon of the present competitive age. Information and a conducive environment of its free flow is a vital tool in all forms of human endeavour. It is the link pin of national development. For a nation to develop it needs to have and provide relevant, updated and adequate information on food security, health, democracy, population, education, family planning, youth empowerment, gender quality, environment etc. The information intermediaries are the persons to modulate these complexities and find match between the information sources and users needs to satisfaction of Ranganathan's law: Books are for use; Every reader his/her book; Every book its reader; Save the time of the reader; Library is a growing organism. The relative importance of these norms in modern context has been evident from experience, study, observations, discussions, etc., and only by scientists and technologists, but also by managers, planners, and policy makers. They recognize the usefulness of information in the performance of their needs information needs. Libraries are therefore proper management, provision and dissemination of such information. It is clearly visible in the contemporary context, that the libraries in the knowledge society are much more than the book depositories This article looks at the theory/practice divide in library and information science and particularly Ranganathan's contributions, basic statements remain as valid in substance if not in expression as -to-day as when they were promulgated, concisely representing the ideal service and organizational philosophy of libraries today.

Analysis of Frequency Sharing Performance using Guard Band and User Device Density in a Urban Environment (도심 환경에서 보호대역과 단말밀도를 이용한 주파수 공유성능 분석)

  • Cho, Ju-Phil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.9
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    • pp.1864-1869
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    • 2012
  • We make an interference analysis to obtain a critical ctiteria for coexisting availability of WLAN and WiBro between adjacent channels can be used in TVWS(TV White Space). To meet this analysis, we set the various transmission parameters including the emission and blocking mask, antenna height and gain, transmission power and bandwidth, channel model etc. And, based on these parameters, we analyze on performances according to a variation of guard band, a number of service user and allowable transmit power of the user operating in the adjacent channels. In this paper, we consider a urban environment and apply a Extended Hata-SRD for WLAN and an interference link and Extended Hata model for WiBro, respectively. With these results, we can see how each system can be shared in an adjacent channel.

A Study on Rate-Based Congestion Control Using EWMA for Multicast Services in IP Based Networks (IP 기반 통신망의 멀티캐스팅 서비스를 위한 지수이동 가중평판을 이용한 전송률기반 폭주제어에 관한 연구)

  • Choi, Jae-Ha;Lee, Seng-Hyup;Chu, Hyung-Suk;An, Chong-Koo;Shin, Soung-Wook
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.1
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    • pp.39-43
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    • 2007
  • In high speed communication networks, the determination of a transmission rate is critical for the stability of a closed-loop network system with the congestion control scheme. In ATM networks, the available bit rate (ABR) service is based on a feedback mechanism, i.e., the network status is transferred to the ABR source by a resource management (RM) cell. RM cells contain the traffic information of the downstream nodes for the traffic rate control. However, the traffic status of the downstream nodes can not be directly transferred to the source node in the IP based networks. In this paper, a new rate-based congestion control scheme using an exponential weighted moving average algorithm is proposed to build an efficient feedback control law for congestion avoidance in high speed communication networks. The proposed congestion control scheme assures the stability of switch buffers and higher link utilization of the network. Moreover, we note that the proposed congestion scheme can flexibly work along with the increasing number of input sources in the network, which results in an improved scalability.

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A Study on the Performance of VPN based on MPLS Networks (MPLS 망을 기반으로 하는 VPN의 성능에 관한 연구)

  • Shin, Tae-Sam;Kim, Young-Beom
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.1
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    • pp.51-57
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    • 2007
  • In this paper we introduce the concept of MPLS-based VPN and propose a scheme for providing VPN services in MPLS networks. Furthermore, we design the control components and the operational procedures and evaluated the performance of traditional VPN implementation methods and MPLS-based VPN. In this scheme it is possible to solve several problems that IP-based VPN pertains via the allocation of VPN ID and virtual space without tunneling, thereby providing effective VPN services. In other words, the MPLS-based VPN scheme uses MPLS networking technology together with the PSTN which can achieve a perfect segregation of user traffic on per-customer basis in a physical link and can guarantee high reliability and security levels. Specially, in the perspective of customers, it can save networking facilities installation and maintenance costs considerably. On the contrary, it possesses some shortcomings in that its deployment tends to be restricted within an ISP's network boundary and it is vulnerable to external security break-ins when going through public networks such as the Internet due to its lack of data encryption capability.

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Traffic characteistics and effective bandwidth estimation for MPEG sources (MPEG 입력 신호원의 트래픽 특성과 효과적 대역폭 추정)

  • 유흥균
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.6
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    • pp.1490-1500
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    • 1996
  • One of the important issues for multimedia communications over ATM netowrks is efficient use of net-work resources since transmitting video at low cost requires high utilization of channel bandwidth. In this paper, we propose an effective bandwidth estimation scheme for MPEG sources in ATM networks. It has been known difficult to allocate effective transmission bandwidth to MPEG sources due to its bursty charactersitics. The MPEG traffic stream can bemodeled using five traffic parameters:service rate, burst load ratio, interburst load ratio, burst period, and interburst period. Using these parameters, a transmission bandwidth for each source can be estimated, and the estimated bandwidth is applied synchronously to reduce the queue size in a buffer. For a simple network modelof a high speed link that multiplexes a number of virtual-circuit connections, simulations on adaptive bandwidth allocation were performed, and the results show that the queueing delay is significantly reduced, when compared to a fixed bandwidth allocation.

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Capacity esitmation of microcell in macro/microcell overlaid W-CDMA WLL system (매크로셀과 마이크로셀이 중첩된 W-CDMA 무선가입자망에서 마이크로셀의 용량 산정)

  • 손성찬;노재성;김수용;조성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.9A
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    • pp.2153-2164
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    • 1998
  • This paper has presented the parameters for the coexistence between two systems in macro/microcell ovelaid W-CDMA WLL (wideband CDMA wireless local loop) and has calculated the capacity of forward/reverse link in microcell. To produce the capacity for analyzing system interference effects, we have shown tables and graphs with the parameters sucyh as RF channel bandwidth of WLL(W), the transmission rate of service message(R), the required signal power to noise power ratio( $E_{b/}$ $N_{0}$) for achieving accepatable error rate, te user number ( $N_{W1}$, $N_{W2}$) of the neighboring system, the signal power to interference power ratio(.GAMMA.$_{C1B}$, .GAMMA.$_{C2B}$) of the neighboring system, the normalized distance(d) between microcell and macrocell base-station, and microcell to macrocell radius ratio ( $R_{d}$). From the results, we have convinced that the capacity of microcell diminishes as increasing the user number ( $N_{W2}$) in macrocell, increasing the microcell radius, and decreasing the normalized distance(d) between microcell and macrocell base-station. Especially, we have known that when $R_{d}$=0.1, $N_{W2}$ must be below 24 at .GAMMA.$_{C2B}$ = 0 dB and below 8 at .GAMMA.$_{C2B}$ = 4 dB for the acceptable capacity raito to be over 80%. Therfore, this paper is usefult to design microcell W-CDMA WLL for accommodating more user number under the interference effects of macrocell W-CDMA WLL and is expected to be reference in power control if base-station.ation.ion.ation.ation.

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Implementation of Mobile Hot-spot Network for Subway Wireless Backhaul Network (모바일 핫스팟 네트워크 기반의 도시철도 무선백홀망 구현)

  • Kim, Dongha;Kim, Ilgyu;Choi, Kyuhyoung
    • Journal of the Korean Society for Railway
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    • v.18 no.3
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    • pp.223-231
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    • 2015
  • This paper proposes a new wireless backhaul technology based on MHN(Mobile Hotspot Network) which uses a wide frequency band of millimeter wave to provide wideband Wi-Fi services for subway passengers. Performance analysis of MHN up and down links, based on data: up and down links structure analysis of physical layer and simulation study of the MHN wireless backhaul link model, show that the proposed MHN-based wireless backhaul network can transmit data at a 1.2Gbps data rate and provide Internet service 100 times faster than that of conventional WiBro-based wireless backhaul networks. These results indicate that the proposed MHN technology is appropriate for subway mobile networks.

A Study on Alternatives for Activating a North Corridor of the Trans Asian Railway according to The Opening of a Cross-Border Freight Railway Service between South and North Korea (남북간 화물열차 개통이후 TAR북부노선 연계.활성화를 위한 대안 연구)

  • Yun, Dong-Hee
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.2303-2315
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    • 2008
  • Finally, Musan-Bongdong section in Kyeong-Ui corridor opened on 11. DEC.2007, which is a historical event, because this connection means the restoration of 56 yrs' disconnection since 1951 and also starting point launching to connect china, Mongolia, Russia for continental railway logistic infrastructure. This is also one of master plans about the northern line in TAR, carried out by UNESCAP, so this study will touch up each country's railway status and the next tasks related with trans-continental railway such as North Korea, Russia, China. Also, this study reveal a mid-long term development strategy to improve the North Korea railroad for a continent rail link and international railroad transportation between China and Russia, and also checks the way of confrontation to the domestic infrastructure for the activation of the continent railway and the north and south, investigates concretely how to establish TAR northern part routes as soon as possible.

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Mediating Effects of Burnout in the Association Between Emotional Labor and Turnover Intention in Korean Clinical Nurses

  • Back, Chi-Yun;Hyun, Dae-Sung;Jeung, Da-Yee;Chang, Sei-Jin
    • Safety and Health at Work
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    • v.11 no.1
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    • pp.88-96
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    • 2020
  • Background: The current lack of the number of nurses and high nurse turnover rate leads to major problems for the health-care system in terms of cost, patient care ability, and quality of care. Theoretically, burnout may help link emotional labor with turnover intention. The purpose of this study was to investigate the mediating effect of burnout in the association between emotional labor and turnover intention in Korean clinical nurses. Methods: Using data collected from a sample of 606 nurses from six Korean hospitals, we conducted a multiple regression analysis to determine the relationships among clinical nurses' emotional labor, burnout, and turnover intention, looking at burnout as a mediator. Results: The results fully and partially support the mediating role of burnout in the relationship between the subfactors of emotional labor and turnover intention. In particular, burnout partially mediated the relationship between emotional disharmony and hurt, organizational surveillance and monitoring, and lack of a supportive and protective system in the organization. In addition, we found that burnout has a significant full mediation effect on the relationship between overload and conflicts in customer service and turnover intention. Although the mediating effect of burnout was significantly associated with the demands and regulation of emotions, no significant effects on turnover intention were found. Conclusion: To reduce nurses' turnover, we recommend developing strategies that target both burnout and emotional labor, given that burnout fully and partially mediated the effects of emotional labor on turnover intention, and emotional labor was directly associated with turnover intention.

An Efficient Algorithm for Finding the Earliest Available Interval on Connection-Oriented Networks (연결 지향 네트워크에서 최초 가용 구간을 찾는 효율적인 알고리즘)

  • Chong, Kyun-Rak
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.3
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    • pp.73-80
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    • 2010
  • The advancement of communication and networking technologies has enabled e-science and commercial application that often require the transport of large volume of data over wide-area network. Schedulable high-bandwidth low-latency connectivity is required to transport the large volume of data. But the public Internet does not provide predictable service performance. Especially, if data providers and users are far away, dedicated bandwidth channels are needed to support remote process efficiently. Currently several network research projects are in progress to develop dedicated connectionsy sA bandwidth scheduler computes an user requested path based on network topology information and link bandwidth allocationsy In this paper, we have proposed an efficient algorithm for finding the earliest time interval when minimum bandwidth and duration are giveny Our algorithm is experimentally compared with the known algorithm.