• Title/Summary/Keyword: Hub System

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An Empirical Study on Competitiveness of Busan Port on Attracting Transshipment Cargo (부산항 환적화물 분석에 유치를 위한 항만경쟁력 관한 실증연구)

  • Lee, Ki-Woong;Lee, Moon-Kyo;Bang, Hyo-Sik
    • International Commerce and Information Review
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    • v.13 no.1
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    • pp.97-120
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    • 2011
  • Purpose of this study is to define competitiveness and attribution factors of Busan port on attracting high value added business such as transshipment cargo. Research finds condition to become optimal transshipment port comprises both internal and external circumstances. As for the internal circumstance, scale and location of the distripark as well as port facilities and the rates, for the external circumstance, international network and information technology on logistics managements are providing positive effects. Optimal plans to attract transshipment cargo should include, first, development of total logistics management system from port entry to unloading, transportation, processing, loading to departure. Second, assign port as free trade zone under customs law to attract foreign investment and goods traffic through tax exemption. Third, unless it is illegal, government needs to grant substantial freedom to shift capital for the foreign investors which will lead increase in cargo traffic and foreign investment.

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A study on Value and Application of Mobile Harbor in Terms of Coastal Transportation (모바일하버(Mobile Harbor)의 가치와 활용방안에 대한 연구 - 연안운송 중심으로 -)

  • Shin, Chang-Hoon;Jeong, Su-Hyun;Park, Soo-Nam
    • Journal of Navigation and Port Research
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    • v.34 no.3
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    • pp.221-228
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    • 2010
  • As container traffic is increasing, the introduction of mega-vessel has had a significant impact on the ports and terminals business. This movement of container shipping has led to intensely competitive environment among ports, so substantial pressures to develop new container ports or to expand existing ones, have been grown. However, it requires a huge investment, especially cost and time, to overcome environmental, geographical and financial restrictions generated from developing a port. This study addressed the Mobile Harbor, the new concept of marine logistics system as an alternative strategy. We performed an economic analysis on the introduction of the Mobile Harbor in coastal transport sector and also a sensitivity analysis to examine the effects of changing factors related on the economic evaluation. We have examined the value and application of Mobile Harbor as a preliminary study, which may contribute to further studies on the Mobile Harbor.

Stress Analysis of Composite Rotor Blade with Sandwich Structure for Medium Class HAWT (좌굴 및 비선형성을 고려한 중형 수평축 풍력터빈용 샌드위치 복합재 회전날개의 설계 개선에 관한 연구)

  • 공창덕;오동우;방조혁
    • Journal of the Korean Society of Propulsion Engineers
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    • v.2 no.3
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    • pp.1-9
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    • 1998
  • The exhaustion of fossil fuels and serious environmental pollution put the concern about non-po llution energy into the world. On the developments of technology, wind energy has been spotlighted as a non-pollution energy in many countries. This study has carried out the aerodynamic and structural design procedure of the lightweight composite rotor blades with an appropriate aerodynamic performance and structural strength for the 500㎾ medium class wind turbine system. The previous design, which is shell-spar structure, is redesigned to shell-spar- sandwich structure for light weight. Large deformation problem from light weight is examined by non-linear analysis. Local buckling occurred under lower stress than failure stress. The buckling analysis is accomplished to confirm the safety of the composite blade. The stress analysis around pin hole joint part at hub is carried out and it is confirmed that the pin hole is not failed. The results show that the resonance of redesigned blade does not happen in operation range.

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Forecasting Cargo Traffic of Zarubino Port with O/Ds of Jilin Sheng in China (중국 지린성 대상의 자루비노항 경유물동량 전망)

  • An, Guo Shan;Koh, Yong Ki;Noh, Jin Ho
    • International Commerce and Information Review
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    • v.18 no.1
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    • pp.81-105
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    • 2016
  • Recently, master plan on the Far East three provinces in China as well as the Russian Far East coupling with 'Eurasia Initiatives' of our government is doubling its importance. It should take advantage of Zarubino port for the hub of Eurasia Logistics Network. This study forecasts the volume demand and whether the expected items of cargo traffic of Zarubino port with O/Ds for the region including the Far East three provinces in China. Input data and the existing basic unit of Korea were utilized in order to overcome the absence of the relevant information to the region. It was derived by them confined to the industrial complex facility in Jilin Sheng on behalf of the Far East three provinces in China as a pilot study. Suitable for the transport sector as a basis for traditional traffic demand, four-step method for estimating the proposed modifications, complementing methodologies. This study is determined that the contribution to the implications on the region's logistics policies of our government has a commitment with raising awareness of the region's Logistics system.

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A Study about Performance Evaluation of Various NoSQL Databases (다양한 NoSQL 데이터베이스의 성능 평가 연구)

  • Park, Hong-Jin
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.3
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    • pp.298-305
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    • 2016
  • Various NoSQL databases are more excellent to process a large amount of big data than existing relational databases such as MySQL, PostgreSQL and Oracle. Among widely used NoSQL databases, performance of HBase, Cassandra, MongoDB and Redis was comparatively assessed. For distributed processing of a large amount of data, 12 servers were connected through switching hub and Ubuntu was installed as operating system. As for benchmark tool, YCSB was applied. Read and update ratios changed from 50% and 50%, 95% and 5% and finally, 100% and 0% and each of them was assessed as 200,000 commands developed into 1,200,000 commands for each case. Cassandra was most excellent with transaction processing per second while MongoDB was most excellent with the number of processes carried out per unit time.

A Multi-hop Reservation Method for End-to-End Latency Performance Improvement in Asynchronous MAC-based Wireless Sensor Networks (비동기식 MAC프로토콜 기반의 무선 센서 네트워크에서 단대단 시간 지연 성능 향상을 위한 멀티 홉 예약 기법의 제안)

  • Hong, Sung-Hwa;Jung, Suk-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.7
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    • pp.2638-2647
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    • 2010
  • X-MAC reduces transmission delay and energy consumption by using a short preamble instead of the existing long preamble. To solve the problem of X-MAC, this paper proposes a new MAC protocol called Express-MAC. The wireless sensor network is mainly used for the purpose of gathering event data or situation information. Especially, the transmission pattern of the sensor network with the purpose of event detection such as intrusion detection is very intermittent as well as successively occurring when a single event takes place in most cases. By reflecting sensor network's key transmission patterns as above, EX-MAC has used multi-hub path's path reservation system and awake section's transmission time reservation method in data transmission when the first event takes place. The awake time reservation in transmission path has improved successive data transmission's end-to-end delay, and it has also increased efficiency in terms of energy consumption by reducing the preamble length of data transmission and reception node.

Effect of Cargo Employee Recognition of Work Environment on the Job Satisfaction and Organizational Commitment in the Port Industry (부산항 항만하역근로자의 근무환경에 대한 인식이 직무만족과 조직몰입에 미치는 영향)

  • Kim, Tae-Min;Ha, Myung-Shin;Choi, Sung-Kwang
    • Journal of Korea Port Economic Association
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    • v.34 no.4
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    • pp.85-104
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    • 2018
  • Globally, more than 90 percent of all international commerce takes place via sea freight. In terms of container cargo volume, Busan Port is the world's sixth largest port, given its geographical conditions. Regarding geographic advantages, a cargo-working operation that met customers' demand using a 24-hour operating delivery system also contributed to the growth of Busan Port as a global hub. However, research and studies on the working conditions for stevedores are lacking, even though the port industry relies heavily on human resources. Therefore, this study identifies the awareness of the working environment by cargo-working employees at Busan Port and their satisfaction level related to their working environment, such as working two shifts in a 24-hour period.

China Effect and Sea/Air Intermodal Transport in Korea (중국효과와 해상/항공 복합운송)

  • Kim, Chang-Beom
    • Journal of Korea Port Economic Association
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    • v.23 no.2
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    • pp.25-40
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    • 2007
  • The sea/air intermodal transport is a time-saving and cost-saving transport for cargo shipments. In reaction to a recent growth of high value-added products in China, the volume of sea/air intermodal transport in Korean airport has been increasing continuously. This paper treats the situation, the system, and the possibility of sea/air intermodal transport, which are emerging as an alternative to solve the logistics problem related to the increase of international air cargo demand in China. Also, several strategies are considered to develope Korea into intermodal transport hub including the value added logistics activity which will secure the demand of sea/air intermodal transport.

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Proposal of Used Books Shared Platform Service for Small-sized Stores (소규모 점포기반 중고서적 공유플랫폼 서비스 제안)

  • You, Seung-Hee
    • Journal of Digital Convergence
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    • v.17 no.9
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    • pp.89-95
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    • 2019
  • he purpose of this study is to propose a shared platform service that can deal with used books based on small stores. The volume of used book market has more than doubled since the book price system, and large bookstores are actively participating in the used book market. Used book sharing platform is an advanced form of online used book direct trade and can be easily used by installing applications on the user's mobile phone. The second-hand book sharing platform is not a shared platform that creates a huge profit-making enterprise, but a future-oriented shared platform that can benefit all users of the platform. If the shared platform, which is the core of the fourth industrial revolution, is applied to almost all small stores and utilized as a hub for second-hand book transactions, it will establish itself as a more reasonable market for second-hand book transactions.

Validation of a 750 kW semi-submersible floating offshore wind turbine numerical model with model test data, part II: Model-II

  • Kim, Junbae;Shin, Hyunkyoung
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.213-225
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    • 2020
  • Floating Offshore Wind Turbines (FOWT) installed in the deep sea regions where stable and strong wind flows are abundant would have significantly improved energy production capacity. When designing FOWT, it is essential to understand the stability and motion performance of the floater. Water tank model tests are required to evaluate these aspects of performance. This paper describes a model test and numerical simulation for a 750-kW semi-submersible platform wind turbine model-II. In the previous model test, the 750-kW FOWT model-I suffered slamming phenomena from extreme wave conditions. Because of that, the platform freeboard of model-II was increased to mitigate the slamming load on the platform deck structure in extreme conditions. Also, the model-I pitch Response Amplitude Operators (RAO) of simulation had strong responses to the natural frequency region. Thus, the hub height of model-II was decreased to reduce the pitch resonance responses from the low-frequency response of the system. Like the model-I, 750-kW FOWT model-II was built with a 1/40 scale ratio. Furthermore, the experiments to evaluate the performance characteristics of the model-II wind turbine were executed at the same location and in the same environment conditions as were those of model-I. These tests included a free decay test, and tests of regular and irregular wave conditions. Both the experimental and simulation conditions considered the blade rotating effect due to the wind. The results of the model tests were compared with the numerical simulations of the FOWT using FAST (Fatigue, Aerodynamics, Structures, and Turbulence) code from the National Renewable Energy Laboratory (NREL).