• Journal of Navigation and Port Research
• /
• v.34 no.3
• /
• pp.243-249
• /
• 2010

The competition between ship management companies is fierce as a result of global trend towards increased specialization. In order for ship management companies to remain competitive, it is necessary to understand the local and global factors and the changing circumstances that impact shipping markets and trade patterns. To better understand these factors, a study and analysis of drawing priority of the competitiveness-evaluation factors of ship management companies was conducted using Analytical Hierarchy Process(AHP) as a method dealing with dicision-making problem. As a consequence of this analysis, it was determined that human resources, both shipboard and land management, were a primary factor in ship management company's competitiveness. Thus, the acquisition and retention of capable staff was a key aspect of assuring a ship management company's competitiveness.

• Journal of Internet Computing and Services
• /
• v.12 no.4
• /
• pp.93-106
• /
• 2011

The Korean mobile telecom market has undergone a sea change since Apple created a new mobile ecosystem with Appstore and iPhone. Many non-telecom operators have been trying hard to come up with new business strategies to gain a competitive edge. The shifting competition landscape requires a new communications policy that can further stimulate the evolving market. This is why countries around the world are upgrading their communications policies: to renew the market foundation and better respond to the ever-changing industry environment. Using the ANP(Analytic Network Process) model, this study identifies policy variables and performs quantitative analysis on their priorities. The analysis results will help prioritize policy variables under the limited amount of resources, and serve as useful guidelines for making mobile ecosystem policies.

• Journal of Korea Port Economic Association
• /
• v.27 no.1
• /
• pp.75-94
• /
• 2011

This paper is concerned about applying the AHP(Analytic Hierarchy Process) for a priority analysis of equipment operation plan to improve productivity of the container terminal in Gwangyang port. In this study, main elements of container terminal are assumed as into yard equipment area, transport equipment area, berth equipment area and C/Center area. A questionnaire is used to collect the opinions of equipment operating department and operational planning department. On the whole, the result of the analyses reveals that the most important area is yard equipment area. Examining each department is responses, equipment operating department preferred the C/Center area to other areas, on the other hand, operational planning department preferred yard equipment area. The result of this study suggests some guidelines for deciding priority of operation plan in the container terminal.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.48 no.1
• /
• pp.33-43
• /
• 2011

This paper proposes a traffic-aware TXOP adjustment algorithm for the IEEE 802.11e networks. In the proposed algorithm the access point (AP) monitors the network traffics periodically and adjusts the TXOP value of the non-QoS traffic in order to improve the network throughput while maintaining the QoS of video and voice applications. The experimental results show that the proposed algorithm outperforms the legacy IEEE 802.11e in terms of the throughput and the fairness.

• Journal of Korea Port Economic Association
• /
• v.26 no.1
• /
• pp.105-130
• /
• 2010

Container terminals in Gwangyang Port are facing in domestically and internationally a lot of changes including opening of Busan New Port and China ports. Compared to new ports, container terminals in Gwangyang Port possess old equipment and facilities. Therefore, in order for Gwangyang Port to maintain its service level and remain competitive, it needs to undergo remodeling to enhance productivity economically. Remodeling activities should be implemented on a continual basis by developing and applying new technologies such as those for gate system, yard system, berth system. In order to review the alternative, we performed questionnaire survey and expert interview. From the results of analysis, we suggested remodeling technology alternatives, priority of remodeling and improvement effect by remodeling introduction stage.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.2
• /
• pp.228-237
• /
• 2021

In those day, the Busan local government had instituted a rule to support and enhance competition as well as improve respect for the ship management industry. This study aims to extract the cause factors to enhance such competition using intuitionistic decision making trial and evaluation laboratory (DEMATEL) and interpretive structural modeling (ISM) methods. First, eight factors were extracted from the specifications in the Ship Management Industry Development Act. Second, the intuitionistic fuzzy number was converted to a crisp number using the standard fuzzy number. Third, the influence relationship was analyzed using DEMATEL, and the priority ranks for the factors are determined using ISM. From the results of the impact relationship analysis, the three main cause factors were determined as improvement of technical ship management capability, improvement of expertise of manpower for onshore management, and improvement of the quality of the Korean seafarer. The priorities under the ISM method, in descending order, were as follows: improvement of the quality of Korean seafarers, improvement of professionalism among the manpower for shore management, improvement of technical ship management capability, improvement of commercial ship management capability, establishment of a comprehensive information system, improvement of the working conditions and employment environment for seafarers, financial support such as overseas orders, and strengthening the availability of foreign seafarers. Therefore, it is necessary to prioritize policy promotion based on these factors, especially the top three, as these have the highest impact.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
• /
• 2002.11a
• /
• pp.281-289
• /
• 2002

전력산업 구조개편 이후 우리나라의 발전시장이 경쟁체제로 전환됨에 따라 원자력발전 사업의 경영 환경이 급변하고 있다. 전력의 안정적 공급이라는 정부 정책 하에 일관되게 추진되어 오던 원자력발전 사업은 원자력 고유의 공공에 대한 안전성을 확보하는 것 이외에도 타 발전원과의 경쟁에서 수익을 창출해야 하는 한편 국가 기간산업으로서의 공익성을 유지하며 국내 원자력 관련 기술 개발을 선도해야 하는 위치로 그 위상이 전환되어야 할 시점에 와 있다.(중략)

• KIPS Transactions on Computer and Communication Systems
• /
• v.5 no.3
• /
• pp.47-54
• /
• 2016

In this paper, we propose a new opportunistic routing scheme based on timed bargaining game. The proposed algorithm effectively formulates the opportunistic routing mechanism as an repeated bargaining model using timed learning method. Additionally, we formulate a new contention window adjusting scheme for reduce collision rate. Simulation results indicate that the proposed scheme has excellent performance than other existing schemes under widely diverse VANET environments.

• Proceedings of the Korean Information Science Society Conference
• /
• 1998.10a
• /
• pp.220-222
• /
• 1998

유선 통신과 다르게 무선 통신은 자원의 한정성이란 매체의 특성을 가지고 있어 다중의 사용자가 다른 QoS를 요구하는 멀티미디어 서비스를 지원하기 위해서는 각각의 서비스에 따른 트래픽에 차별화를 두어 매체 접속을 제어하는 것이 효과적인 방법이 될 것이다. 현재, 음성과 데이터를 통합하여 매체 접속 제어를 하는 패킷 예약 다중 접속 방식은 많은 연구가 이루어진 상태이고, 특히, 멀티미디어 지원을 위해 적응형 패킷 예약 다중 접속(APRMA: Adaptive Packet Peservation Multiple Access)방식의 연구가 진행되었다. 본 논문에서는 멀티미디어 지원을 위한 다른 한가지 방법으로 패킷이 경쟁에 참여할 수 있는 파라미터를 서비스의 종류와 활성중인 슬롯의 수에 따라 조정하여 채널의 효율을 보다 향상시키고 패킷 충돌이 일어날 확률도 감소 시킬 수 있는 우선 순위 기반 적응형 패킷 예약 매체 접속 방법 (APRMA_P : APRMA with Prioroty)을 제시한다. 제안된 APRMA_P의 성능을 분석하기 위해 시뮬레이션을 통해서 체널 효율을 기존의 APRMA와 비교 분석한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06d
• /
• pp.262-265
• /
• 2010

멀티미디어 스트리밍은 인터넷에서 이미 가장 인기있는 서비스가 되었다. 멀티미디어 스트리밍 서비스를 제공하기 위해서는 충분한 대역폭과 딜레이가 유지되어야 한다. 기존의 무선 멀티홉 네트워크는 이러한 요구사항을 만족하기 어렵다. 본 논문에서는 멀티미디어 스트리밍을 보다 좋은 품질로 서비스하기 위해 802.11e를 사용한 Hop Based Priority 테크닉을 제안한다. HBP 테크닉은 패킷이 경로를 따라 이동할때 한홉이 지날때마다 우선순위를 증가시킨다. 그럼으로써 먼저 보낸 패킷과 나중에 보낸 패킷간의 경쟁을 최소화 시키고 먼저 보낸 패킷이 채널을 잡을수 있도록 한다. 이를 모델링을 통해 검증하여 약 43%의 성능 개선 효과가 있음을 확인하였다.