• Title/Summary/Keyword: 효율성 향상

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An Analysis on Current Status of and Perception of Subject Specialized Services in Korean Special Libraries (전문도서관의 주제전문서비스 운영 현황과 사서의 인식 분석)

  • Hwang, Jae-Young
    • Journal of Korean Library and Information Science Society
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    • v.42 no.4
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    • pp.137-158
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    • 2011
  • Recently, subject specialized service has been suggested as a solution to overcome a difficulty of library management and to meet the quickly changing needs of library users. Introduction of subject specialized service is raised to be introduced to special libraries and efficient management system is required. However, systematic study on the subject specialized service is very rare. This study investigates and analyzes how subject specialized service is operated in korean special libraries and how subject specialist librarians recognize them. In order to analyzes and investigate, 8 special libraries was selected to survey general management of subject specialized service, recruitment and training issues of subject specialist librarian, their duties and overall evaluation and problem of subject specialized service. Finally the study attempts to suggest development strategies in order to improve subject specialized service in special libraries.

A Study on Yard Operation in Container Terminal (컨테이너 터미널에서의 장치장 운용 계획에 관한 연구)

  • Kim Kap-Hwan;Kim Jae-Joong;Ryu Kwang-Ryel;Park Nam-Kyu;Choi Hyung-Rim;Jeon Su-Min
    • Journal of Intelligence and Information Systems
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    • v.12 no.1
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    • pp.125-137
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    • 2006
  • One of the important tactical problems for the efficient operation of container terminals is to determine the usage of storage space There are two different strategies for stacking containers; mixing strategy, in which outbound containers and inbound containers are mixed in the same block, and segregating strategy, in which outbound containers and inbound containers are stacked in blocks different from each other The performance of space allocation strategies also depends on the types of handling equipment in the yard and the number of handling equipment allocated to each block. A simulation model is developed considering various handling characteristics of yard cranes. Performances of various space and equipment allocation strategies are evaluated by using the simulation model.

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A Study of MIMO FTN Scheme based on Layered Space Time Code using Turbo Code (터보부호를 이용한 계층적 시공간 부호기반 MIMO FTN 전송기법 연구)

  • Park, Gun-Woong;Jung, Ji-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.5
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    • pp.895-901
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    • 2016
  • The next generation wireless and satellite communications require high transmission efficiency and high reliability to provide various services with subscribers. To satisfied these requirements, incorporated MIMO (Multiple Input Multiple Output) system with FTN (Faster Than Nyquist) techniques based on layered space time coded method are considered in the paper. To improve performance, STTC (Space Time Trellis Code) was employed as an inner code. As the same as SISO (Single Input Single Output) system, the outer codes are turbo codes. In receiver side, BCJR algorithm is used for STTC decoding in order to eliminate interferences induced by FTN transmission. They can yield significantly increased the data rates and improved link reliability without additional bandwidth. Therefore, we proposed a new decoding model for MIMO FTN model and confirmed that performance was improved compared to conventional SISO model according to amount of interference for FTN.

A Genetic Algorithm for Network Clustering in Underwater Acoustic Sensor Networks (해양 센서 네트워크에서 네트워크 클러스터링을 위한 유전 알고리즘)

  • Jang, Kil-Woong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.12
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    • pp.2687-2696
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    • 2011
  • A Clustering problem is one of the organizational problems to improve network lifetime and scalability in underwater acoustic sensor networks. This paper propose an algorithm to obtain an optimal clustering solution to be able to minimize a total transmission power for all deployed nodes to transmit data to the sink node through its clusterhead. In general, as the number of nodes increases, the amount of calculation for finding the solution would be too much increased. To obtain the optimal solution within a reasonable computation time, we propose a genetic algorithm to obtain the optimal solution of the cluster configuration. In order to make a search more efficient, we propose some efficient neighborhood generating operations of the genetic algorithm. We evaluate those performances through some experiments in terms of the total transmission power of nodes and the execution time of the proposed algorithm. The evaluation results show that the proposed algorithm is efficient for the cluster configuration in underwater acoustic sensor networks.

Division of Work Regions for Operating the Yard in a Container Terminal (작업 영역 구분을 이용한 컨테이너 터미널의 장치장 운영 전략)

  • Ahn, Eun-Yeong;Park, Tae-Jin;Ryu, Kwang-Ryel
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2007.12a
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    • pp.335-336
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    • 2007
  • This paper propose a heuristic method that divides the block into some work regions to operate stacking cranes efficiently in a automated container terminal where the blocks with non-crossing stacking cranes(SC) are laid out in perpendicular to the quay. Typically, fund over between SCS and trucks occur at each side if the blocks, and each if the landside and seaside SCS is responsible for the jobs that occur at its own side. When a container to be fetched is located far from fund over point, the SC should move a long distance and the interference between the two cranes am occur, which decreases the productivity of the SCS. Therefore, our method divides the block into two exclusive and one shared regions and let the containers located far from their fund over points to be transferred to the shared region by the other side crane before they are carried out. Although simple this method am reduce the crane movement and the interference between the two cranes. Simulation experiment shows that our proposed method significantly improves the productivity if the container terminal than previous heuristic that does not divide work regions.

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Suggestions on Efficient O&M Plan for Improving Users' Satisfaction on the University Dorm Facilities (대학 기숙사 시설의 사용자 만족도 향상을 위한 효율적인 유지보수관리(O&M) 방안 제안)

  • Kim, Min Soo;Kim, Yujin;Kim, Jun Ha
    • Journal of the Korean Institute of Educational Facilities
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    • v.24 no.5
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    • pp.11-18
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    • 2017
  • An university dorm has significant implications in terms of providing residential, living, and learning spaces. With its supportive function, a dorm enables each university to provide higher level of education. The operation & maintenance(O&M) condition of the dorm has a decisive effect on the students' satisfaction. Accordingly, high levels of O&M services should be performed for students. However, Korean dorms are being operated and maintained by their own O&M guidelines without the consideration of spatial characteristics of dorm facilities and the comprehensive and systematic understanding on effective O&M processes. Given the fact that dorm facility can be a crucial factor in determining the entire quality of university and its O&M condition is closely related to the satisfaction of students, it is imperative that we need to pay more attention to the O&M condition and services. Therefore, the main objective of this research is to improve dorm students' satisfaction levels by applying different O&M method, preventive maintenance rather than reactive maintenance which has been performed so far. In ordering for doing it, 'Facility Management(FM) Standard' from KS, 'Facility Performance Indicator(FPI)' from APPA: Leadership in educational facilities and 'Building O&M Inspection Manual' from Korean Ministry of Land, Infrastructure and Transport were analyzed to come up with 15 significant O&M factors. After extracting O&M factors, the survey was conducted to determine importance rate and performance rate of each O&M factor. Using the Important-Performance Analysis(IPA), the priority of 15 O&M factors was established. The result of this research will be helpful for the efficient dorm facility O&M services and for facility managers to appropriately allocate the limited resources and human power.

Construction of an Automatic Instruction-Set Extension System for Efficient ASIP Design (효율적인 ASIP 설계를 위한 자동 인스트럭션 확장 시스템 구축)

  • Hwang, Deok-Ho;Hwang, Sun-Young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38B no.1
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    • pp.1-9
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    • 2013
  • This thesis proposes an automatic instruction extension system that utilizes retargetable compiler, based on MDL, to design an ASIP optimized for application. The proposed system uses information gathered from the application program to find all possible expandable instruction candidates. Expandable instruction candidates acquire the realization characteristics through hardware library. The system chooses instruction set and optimizes processor structure satisfying constraints on the bases of hardware characteristics and increase in execution speed. To confirm the efficiency of the proposed system, automatic instruction extension system was performed using various benchmark applications. The proposed system acquired optimized instruction set and processor structure, which are expanded from the commercial version of ARM9TDMI. Experimental results show that number of execution cycle has been reduced by 33.5% when compared to conventional version of ARM9TDMI, while area has been slightly increased.

An AODV-Based Two Hops Dynamic Route Maintenance in MANET (MANET에서의 AODV 기반 2홉 동적 경로유지 기법 연구)

  • Moon, Dae-Keun;Kim, Hag-Bae
    • The KIPS Transactions:PartC
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    • v.14C no.2
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    • pp.191-198
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    • 2007
  • A mobile ad-hoc network (MANET) is an autonomous, infrastructure-less system that consists of mobile nodes. In MANET, on demand routing protocols are usually used because network topology changes frequently. AODV, which is a representative on demand routing protocol, operates using the routing table of each node that includes next hop of a route for forwarding packets. It maintains the established route if there is not an expiration of route or any link break. In the paper, we propose a partially adaptive route maintenance scheme (AODV-PA) based on AODV, which provides dynamic route modification of initial route for selecting the effective route using not only next hop but also next-hop of next-hop (i.e. 2-hop next node) acquired through route discovery process. In addition, the proposed scheme additionally manages the routing table for preventing exceptional link breaks by route modification using HELLO messages. We use NS 2 for the computer simulation and validate that the proposed scheme is better than general AODV in terms of packet delivery ratio, latency, routing overhead.

Design and Evaluation of Hybrid Tag Interface (하이브리드 태그 인터페이스 디자인 및 평가)

  • 윤형민;이창수;신현구;권오영;손영우;한탁돈
    • Journal of KIISE:Software and Applications
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    • v.31 no.11
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    • pp.1483-1495
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    • 2004
  • Recently, new computing technologies are emerging from various life environments, as a result of the spread of network environments and the advent of new computing devices. This trend in computing technology is called "Ubiquitous computing" and is being developed to provide a convenient lifestyle through the dynamic integration of physical objects and digital information. The hybrid tag interface suggested in this paper is a usage model that integrates widely used image codes and recently applied RFIDs in various applications. On the basis of this concept, we eventually designed five different models such as Dual, Partial, Relative, Rebind and Discrete types according to their interrelation. In this paper, the characteristics of tag interfaces in the form of image codes and RFIDs are analyzed and the hybrid tag interface is proposed here for more efficient and convenient interface.

An Efficient CGI Gateway in the UNIX System (유닉스 시스템에서 효율적인 CGI 게이트웨이)

  • 이형봉
    • Journal of KIISE:Computing Practices and Letters
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    • v.10 no.1
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    • pp.66-74
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    • 2004
  • To get changing data or retrieved information in a web service environment, we need the CGI method in which we designate an executable file and receive the output of the executable file as a document. But the original CGI method has some performance pitfalls caused by the native condition that a process for the requested executable file should be created every time it is requested. Several approaches that make the process as a daemon wholly or partly have been made to solve those problems and they have exclusive strength and weakness. So, many developers are confused when they have to choose which of the CGI methods. We proposed an efficient CGI gateway design called SendFD that the main part of CGI gateway was separated as a daemon and taken over the communication channel by the other small part forked whenever it was requested. Then we testified the efficiency of SendFD styled CGI gateway in real web service environment and it showed about 3% performance improvement compared to the conventional socket pipe method.