• Title/Summary/Keyword: Terminals

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Design and Performance Analysis of Satellite Terminal Management Protocol in KMILSATCOM (군 위성통신체계 위성단말관리 프로토콜 설계 및 성능분석)

  • Lee, Jong-Seong;Choe, Hyeong-Seok;Hwang, In-Gwan
    • Journal of Satellite, Information and Communications
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    • v.2 no.1
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    • pp.14-20
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    • 2007
  • The Korean Military Satellite Communication System (KMILSATCOM) is composed of military payload of KOREASAT 5 and military satellite terminals. The military satellite terminals communicate with each other in satellite service area. The satellite terminal management system is developed for centralized management of satellite terminals and communications link. The satellite terminal management system dose not use terrestrial networks (i.e. Fiber optic, Microwave) for management because the KMILSATCOM is system for emergency (i.e. war time) and the satellite terminals has to move to operational area, so the management link must use satellite link. The management link is composed of 1 to N communication scheme for one manager and multiple terminals. This paper describes the satellite terminal management protocol architecture and the performance of the protocol of the KMILSATCOM system.

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A Study on Optimized Decision Model for Transfer Crane Operation in Container Terminal (컨테이너터미널 트랜스퍼 크레인의 배정 및 이동경로 최적화 모델)

  • Shin, Jeong-Hoon;Yu, Song-Jin;Chang, Myung-Hee
    • Journal of Navigation and Port Research
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    • v.32 no.6
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    • pp.465-471
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    • 2008
  • As the excessive competition between container terminals has been deepening, not only productivity, but also cost economic of the terminals has been raised. With regard to this, the competitiveness of the terminals is limited because of inefficiency operation of transfer crane(T/C) which needs large amount of energy consumption. Therefore, it is possible that the improvement in the T/C operation leads to saving cost for resources and energy as well as increasing the productivity of the terminals. This study provides 'the K-Means Clustering based Optimized Decision Model for Transfer Crane Operation', referring to 'RFID & RTLS based Port Logistics Initiative' of Ministry of Land, Transportation and Maritime Affairs and estimates the efficiency through simulating.

A Study on Container Terminal Layout and the Productivity of Container Crane During Ship Turnaround Time (컨테이너 터미널 배치 형태와 본선작업 생산성에 대한 연구)

  • Shin, Sung-Ho;Kim, Yeonkook J.
    • Journal of Korea Port Economic Association
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    • v.39 no.1
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    • pp.47-63
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    • 2023
  • In smart ports and port automation, the number of vertically deployed container terminals is growing. The purpose of this study is to analyze the productivity of horizontally arranged and vertically arranged container terminals by comparing the main ship operation time, and to recommend future strategies for increasing the operational efficiency of vertically configured container terminals. To achieve our goal, we chose two terminals representating each type, and collected berth allocation status data from 2018 to 2022. Then we analyzed the data using the Accelerated Failure Time (AFT) model, a parametric survival analysis technique. Under the assumption that the working circumstances of the C/C (Container Crane) are the same, we find that the productivity of on-board work of the vertically placed container terminal is higher than that of the horizontally placed container terminal. Our result also shows that the productivity is reduced during the COVID-19 period and the European ships show lower onboard work time. On the basis of these findings, we propose strategies to improve the productivity of vertical container terminals.

Economic Efficiency of the Korean Container Terminals: A Stochastic Cost Frontier Approach

  • Seokwoo Jake Choi;Gi-Su Kim;BoKyung Kim
    • Journal of Korea Trade
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    • v.26 no.3
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    • pp.23-44
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    • 2022
  • Purpose - Recent issues such as vessel enlargement, strengthening of environmental regulations, and port smartization are expected to increase costs and intensify competition in the port industry. In the new normal era, when external growth has reached its limit, the efficient operation of ports is becoming indispensable for achieving sustainable growth. This study aims to identify the determinants of inefficiency by examining the cost structure and efficiency of container terminals in Korea and furthermore propose the political implications to derive the maximization of efficiency. Design/methodology - This study estimates the cost function of container terminal operators and identifies the efficiency of container terminals using stochastic cost frontier (SCF) in the first stage. In the second step, the SCF results are compared with the data envelopment analysis (DEA). Last, this paper proposes efficiency determinants on container terminal operation to establish appropriate strategies. Out of the 29 container terminal operators in South Korea, 13 operators participated in the survey. The translog cost function was estimated utilizing a total of 116 observations collected over the 2007-2017 period. Findings - Empirical analysis shows that economies of scale exist in Korea's container ports, which provides a rationale for the government's policy to establish the global terminal operator by integrating small terminal operators to enhance competitiveness. In addition, as a result of the determinants analysis, container throughput, weight of direct employment costs, and labour cost share have positive effects on improving cost efficiency, while inefficiency increases as the length of quay increases. More specifically, cost efficiency improves as the proportion of direct employment costs to outsourcing service costs increases. Originality/value - This study contributes to analyzing the inefficiency factors of container terminals through efficiency analysis with respect to a cost function. In addition, this study proposes the practical and political implications, such as establishing a long-term manpower pool, the application of the hybrid liner terminal system, and the construction of a statistical data system, to improve the cost inefficiency of terminal operators.

A Review on Yard Management in Container Terminals

  • Zhen, Lu;Jiang, Xinjia;Lee, Loo Hay;Chew, Ek Peng
    • Industrial Engineering and Management Systems
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    • v.12 no.4
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    • pp.289-304
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    • 2013
  • With advancements of quay side equipments and technologies, the bottleneck of port operations has moved from quay side to yard side. The yard management of a port has significant influences on the competitiveness of a port in the global shipping network. The research area of yard management has attracted a lot of attentions from both the academia and the industrial practitioners. This paper gives a comprehensive review for the studies on the yard management in container terminals. From three aspects, i.e., yard cranes management, yard vehicles management, and yard spaces management, this paper reports the advances in these three areas. Some future directions on the yard management researches are also discussed. The purpose of this paper is to stimulate more practically relevant researches in this emerging area.

Development and Characteristics of an Electronic Starter with Three Terminals for 32Watt Fluorescent Lamps (32Watt 형광등용 3단자 반도체 스타터의 개발 및 특성)

  • Park, Chong-Yeon;Jee, Kwang-Hyeon;Kim, Un-Kwang
    • Journal of Industrial Technology
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    • v.17
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    • pp.175-182
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    • 1997
  • Various types of electronic starter have been developed for the general fluorescent lamps with magnetic-type ballasts. However, the FL032/T8 fluorescent lamp requires higher voltage to discharge the lamp. The general starter with two-terminal is not suitable for the FL032/T8 slim-line type fluorescent for its higher discharge voltage. The suitable starter with three terminals have been studied for the FL032/T8 lamp in this paper. The developed starter have better characteristics in view points of the discharge voltage magnitude. We have proposed and designed the three terminals electronic starter. The proposed starter have been experimented and compaired with the other 2-terminal general starters. By the experimental results, we have concluded that the proposed starter is suitable to the FL032/T8 lamp.

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Load Scheduling Using a Genetic Algorithm in Port Container Terminals (컨테이너 터미날에서의 유전자 해법을 이용한 적하계획법)

  • Kim, Kap-Hwan;Kim, Ki-Young;Ko, Chang-Seong
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.4
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    • pp.645-660
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    • 1997
  • An application of the genetic algorithm(GA) to the loading sequencing problem in port container terminals is presented in this paper. The efficiency of loading operations in port container terminals is highly dependent on the loading sequence of export containers. In order to sequence the loading operation, we hove to determine the route of each container handling equipment (transfer crane or straddle carried in the yard during the loading operation. The route of a container handling equipment is determined in a way of minimizing the total container handling time. An encoding method is developed which keeps intermediate solutions feasible and speeds up the evolution process. We determine the sequence of each individual container which the container handling equipment picks up at each yard-bay as well as the visiting sequence of yard-bays of the equipment during the loading operation. A numerical experiment is carried out to evaluate the performance of the algorithm developed.

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A Model of Evaluating the Efficiency of Container Terminals for Improving Service Quality (서비스 품질 향상을 위한 컨테이너 터미널의 효율성 평가 모형에 관한 연구)

  • 임병학;한윤환
    • Journal of Korean Society for Quality Management
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    • v.32 no.2
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    • pp.77-92
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    • 2004
  • It is difficult but very necessary to measure the productivity of container terminals as logistics service provider. It is meaningful to find the appropriate inputs and outputs of the logistics service delivery systems and to measure the relationship between these inputs and outputs. This study proposes a model of evaluating the efficiency of container terminals. The evaluation consists of three phases. First, DEA(Data Envelopment Analysis) phase, determines the efficiency score and weights of DMUs(Decision Making Unit). This phase performs through four steps : selection of DMU, selection of DEA model, determination of input and output factors, calculation of efficiency score and weights for each DMU. Secondly, CEM (Cross Evaluation Model) phase, is to calculate the cross-efficiency scores of DMUs. This phase performs through three steps: selection of CEM, determination of cross-efficiency score for each DMU and development of cross-efficiency matrix. Finally, average cross-efficiency analysis phase is to compute the average cross-efficiency score. The proposed model discriminates among DMUs and ranks DMUs, whether they are efficient or inefficient.

A Study on Mobile IPv4 Authentication Mechanisms

  • Lim, Jung-Muk;Lim, Hyung-Jin;Chung, Tai-Myoung
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.277-280
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    • 2005
  • With the proliferation of mobile terminals, use of the Internet in mobile environments is becoming more common. To support mobility in these terminals, Mobile IPv4 is proposed and represents the standard in IPv4 environments. Authentication should be mandatory, because mobile terminals can utilize Internet services in any foreign domain. Mobile IPv4 provides symmetric key based authentication using the default HMAC-MD5. However, symmetric key based authentication creates a key distribution problem. To solve this problem, public key based authentication mechanisms have been proposed. In this paper, the performance of each of these mechanisms is evaluated. The results present that, among these mechanisms, partial certificate based authentication has superior performance, and certificate based authentication has the worst performance. Although current public key based authentication mechanisms have lower performance than symmetric key based authentication, this paper presents the possibility that public key based authentication mechanisms may be used for future mobile terminal authentication.

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A Study of Non-PC Device Application Service and A Prospect for Service Platform (Non-PC 형 정보단말 응용서비스 및 서비스 플랫폼 전망)

  • Kim, Dong-Hoon;Bae, Jung-Il;Kim, Su-Jin;Yeon, Seung-Ho
    • 한국정보통신설비학회:학술대회논문집
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    • 2007.08a
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    • pp.100-103
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    • 2007
  • For several ten years, the Internet and IT services have been greatly developed in PC area and with this, new BM and services with terminals like Post-PC and Non-PC types will come into the spotlight in few years. In various fields of service, terminals exclusive to individual service come into the market already, the hardware and the contents used in the terminals are circulating. The communication service providers are very enthusiastic about developing and providing various services in order to overcome the growth limit of existing network connection service. And they think that providing the Non-PC type Information Appliance services will make added values and be sources of making profits in next generation. Hereupon we are going to observe the Non-PC type Information Appliance services, the structure of the service platform that make that services possible, and their prospect.

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