• Journal of Korean Society for Atmospheric Environment
• /
• v.17 no.1
• /
• pp.85-96
• /
• 2001

The objective of this study is to develop the water spraying which can effectively by applied to the control or suppression of the fugitive dust generated from the scrap metal handling area at the Port of Inchon. As a first step toward this goal, we carried out some preliminary analyses on the chemical composition, physical shape, and particle size distribution of the sample dust. Next, to quantitatively investigate the effect of adding surfactants to the spraying water on the wettability of the sample dust, the Standard Sink Test was carried out for four different surfactants and at six different concentrations using the surfactants considered in this study. Results of from the preliminary analysis indicated that the main chemical component consisting of the sample dust is Goethite(FeO(OH)) and that the particles smaller than 10 ${\mu}{\textrm}{m}$ in geometric diameter occupy about 36% of the sample dust in mass. This result implies that the fugitive dust generated from the scrap metal handling area at the Port of Inchon should affect the environment nearby more than we have expected. This is because of relatively large mass percentage of the small metal particles less than 10${\mu}{\textrm}{m}$ in geometric diameter, what we may call respirable particles. As for the results of the Standard Sink Test, higher surfactant concentration tends to result in the higher wettability of the sample dust for the surfactants considered in this study, which in turn ensures the high particle collection efficiency of the droplets generated from the water spraying system. Based upon this preliminary results, studies to develop more sophisticated scaled model for dynamic test in underway and the effort to find the best surfactants as well as the optimum operating conditions are being made at the same time.

• Journal of the Society of Naval Architects of Korea
• /
• v.43 no.5 s.149
• /
• pp.560-567
• /
• 2006

FPSO and shuttle tanker are connected to each other by a mooring hawser and a loading hose through which cargo oil is off-loaded. Even in mild sea-state. environmental loads can cause unstable large drift motions between two vessels in tandem off-loading operations, which may result in collision incidents. Accordingly. the analysis on the relative motion between two vessels due to the environmental loads should be investigated in initial design stage. In this study, the low speed maneuvering equation is employed to simulate nonlinear motions of FPSO and shuttle tanker. Low frequency wave drift forces including hydrodynamic interactions between two vessels are evaluated by near field approaches. Current loads are determined by mathematical model of MMG and wind loads are calculated by employing the wind spectrum according to the guidelines of API-RP2A. Mooring forces produced by turret mooring lines and a flexible hawser are modeled quasi-statically by catenary equations. The effect of environmental loads that affect nonlinear motion is investigated through variation in their magnitudes and the nonlinear motions between FPSO and shuttle tanker are simulated under wave, current and wind in time domain.

• Journal of Korea Society of Industrial Information Systems
• /
• v.12 no.2
• /
• pp.37-48
• /
• 2007

In order to become a mega hub port, major ports all over the world are making every effort to enhance their productivity through efficiency of internal operation and introduction of the state-of-the-art technologies. They are not only installing various kinds of high-technology equipments but also introducing advanced technologies for the development of an effective gate system. Recently thanks to the appearance of RFID (radio frequency identification) and OCR (optical character recognition) technology, major container terminals are stewing up the automation of truck and container identification at the container luminal gate. This study aim to develop an automated gate system for identification task based on RFID and OCR technology. It will make mn effective gate operations in a container terminal.

• Journal of Navigation and Port Research
• /
• v.29 no.10 s.106
• /
• pp.847-852
• /
• 2005

In order to evaluate the safety of navigation at sea and the safety of mooring on berthing, it is necessary that the wave and wind induced ship dynamic motion should be measured in real time domain for the validity of theoretical evaluation method such as sea-keeping performance and safety of mooring. In this paper, the basic design of sensors is discussed and some system configurations were shown. The developed system mainly consists of 4 kinds of sensors such as three-dimensional accelerator, two-dimensional tilt sensor, azimuth sensor and two displacement sensors. Using this measuring system, it can be obtained the 6 degrees of freedom of ship dynamic motions at sea and on berthing such as rolling, pitching, yawing, swaying, heaving, surging under the certain external forces.

• Journal of Korea Port Economic Association
• /
• v.24 no.2
• /
• pp.265-287
• /
• 2008

This paper studies the economic effects of port-liquid freight by focusing on Ulsan port and its regional economic effects. The direct industrial effects of port-liquid freight are analysed to be an increase in about 1billion dollars' worth of production of the regional port-logistic industry, an increase in about 0.22billion dollars' worth of value-added of the industry, and the creation of about 2,600 employment in the industry. Including the indirect effects, the total effects on Ulsan regional economy are estimated to be an increase in about 1.9billion dollars worth of production, an increase in about 0.51billion dollars' worth of value-added and an increase in about 6,442 employment.

• Journal of Korea Multimedia Society
• /
• v.12 no.11
• /
• pp.1671-1679
• /
• 2009

The existing subjects of supply chain management, which link business firms to customers, have focused on forward logistics such as acquisition of low and subsidiary parts, manufacturing, distribution and sales. Consequently, it is emphasized that supply chain management has to be a sustainable business activity. Nevertheless, capabilities of reverse supply chain management for domestic companies are still relatively limited compared to advanced foreign companies. For this reason, this study aims to develop the service platform, which provides information on return, retrieval, abolish and recycling using RFID, includes information on packing, placement, loading and unloading and transportation of the goods. In order to achieve the purpose of this study, the research previous studies and analyze achieved diverse cases on reverse logistics, review the present state, and propose service platform application to manage reverse supply chain which will be applied.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.18 no.1
• /
• pp.35-42
• /
• 2006

Recently, the harbor function is being reconsidered with the viewpoint of logistics, and various efforts are given to enhance the harbor performance agglomerating all procedures of stevedoring, treatment and background transportation of freight. The harbor performance largely depends on the efficient combination of the engineering part of harbor construction and the forthcoming logistics part. It may thus be anticipated in the future that the design concept of harbor construction will be transferred to a comprehensive consideration integrating both engineering and logistics parts to maximize the ultimate harbor operational performance. In the present study, various indicators for assessing a modem container terminal performance are presented far the purpose of helping harbor engineers understand the fundamental logistics through container handling operations. The indicators are compared, analyzed and compiled, by referring to the practical cases of Busan and Gwangyang ports as an illustration.

• 한국방재학회:학술대회논문집
• /
• 2011.02a
• /
• pp.53-53
• /
• 2011

최근에 세계화, 무역자유화에 따른 컨테이너 물동량이 증가하고 있다. 그에 발맞추어 초대형 컨테이너선이 등장하게 되고 신개념, 고효율의 항만인프라의 도입이 요구되고 있다. 이런 배경에 따라 최근에 국내외에서 부유식 안벽에 관한 기술 개발 및 연구가 더욱 필요한 상황이다. 부유식 안벽은 이동가능한 부유식 구조로 기존 항만의 확장 또는 신규 항만 건설시 환경문제를 최소화하고 기항, 선박수 및 선박의 크기에 따른 안벽 배열을 최적화 할 수 있어 항만 기능을 고도화함으로써 녹색항만을 구현하는데 많은 기여를 하게 될 것이다. 특히 컨테이너선의 양현하역과 환적이 가능하게 되어 컨테이너 터미널의 화물처리능력을 확대할 수 있을 뿐 아니라 기항선박의 체류시간을 최소화 할 수 있는 장점이 있다. 또한, 우리나라는 삼면이 바다로 크고 작은 항만들이 해안선을 따라 위치하고 있다. 이러한 항만들을 안전하게 보호하기 위한 방파제는 항만 기본시설인 외곽시설 중의 가장 중요한 구조물이다. 국내에 설치된 방파제는 대부분 사석이나 케이슨을 이용한 중력식 방파제로써 해저에 고정되어 해수면상으로 건설되므로 항내 외 해수교환을 차단하여 항내 수질악화를 초래할 뿐만 아니라 수심에 따라 막대한 건설비용이 소요된다. 따라서 친환경적이고 경제적인 새로운 형식의 방파제에 대한 연구 및 개발이 필요한 실정이다. 그 중 하나의 대안인 부유식 방파제는 공사기간이 짧고 비교적 수심에 대한 제약이 없는 것이 특징이다. 또한 해수의 원활한 흐름이 가능하기 때문에 중력식 방파제에 비해 경제적이며, 환경적 측면에서 큰 장점이 있다. 하지만 아직까지 부유식 방파제에 대한 국내 및 해외에서의 연구는 이론적인 해석을 중심으로 이루어져 부유식 방파제 실용화를 위한 많은 연구가 수행되어야 할 것으로 판단된다. 본 연구에서는 부유식 안벽 내에서 정온도를 효과적으로 유지하기 위하여 부유식 방파제를 설치하고 소파성능과 부유식 안벽내의 영향성을 수리모형실험을 통해 분석하였다.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.13 no.2
• /
• pp.83-90
• /
• 2010

The hydrodynamic interaction of two floating bodies in waves freely floating or connected by a rigid link is studied by using a boundary element method in the frequency-domain. The exact two-body hydrodynamic coefficients of added mass, wave damping and exciting force are calculated from the radiation-diffraction potential solution of the improved Green integral equation associated with the free surface Green function. The irregular frequencies in the conventional Green integral equation make it difficult to predict the physical resonance of the fluid in the gap between two bodies floating side by side. However, the improved Green integral equation employed in this study is free of irregular frequencies and always yields the exact solution of the multi-body radiation-diffraction potential boundary value problem. The 6 degree-of-freedom motions of two bodies freely floating side by side or connected parallel by a rigid link have been calculated for the incident wave frequencies ranging from 0.1 to 5 radians per second in head, left and right bow quartering seas. The 6-component load of the rigid link have also been presented.

• Journal of Intelligence and Information Systems
• /
• v.15 no.3
• /
• pp.137-150
• /
• 2009

This paper proposes the hybrid heuristic method to apply the opportunity time to solve the vehicle routing and scheduling problem with time constraints(VRSPTW). The opportunity time indicates the idle time which remains after the vehicle performs the unloading service required by each customer's node. In this proposed heuristic, we add the constraints to VRSPTW model for the opportunity time. We also obtain the initial solution by applying the cost evaluation function to the insertion strategy considering the opportunity time. In addition, we improve the former result by applying the opportunity time to the tabu search strategy by swapping the customer's node. Finally, we suggest the construction strategies of initial routing which can efficiently acquire the nearest optimal solution from various types of data in terms of geographical condition, scheduling horizon and vehicle capacity. Our experiment show that our heuristic can get the nearest optimal solution more efficiently than the Solomon's I1 heuristic.