• Journal of Advanced Research in Ocean Engineering
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• v.4 no.4
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• pp.204-216
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• 2018

A ship repeatedly face free surface under rough sea conditions owing to relative motion with wave encounter. The impact pressure is transferred to the hull structure and causes structural damage. In this study, the bow flare slamming load of a container ship is estimated using computations fluid dynamics (CFD) and prescript formula according to various classifications. It is found that the bow flare slamming load calculated by the formulas of the common structural rule and ABS tends to be similar to the CFD results.

• Journal of the Semiconductor & Display Technology
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• v.18 no.4
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• pp.129-133
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• 2019

In this paper, we developed a system to monitor the storage capacity of suction-type device such as vacuum cleaner or crop harvesters. The monitoring system consists of load cells and a differential pressure sensor which simultaneously monitor the weight and volume of the stock. Since weighing objects stored in storage containers alone cannot fully monitor the level of filling, more accurate monitoring can be achieved by monitoring volume and fusion with weight information. The volume was monitored using a phenomenon in which the flow rate of the inhaled air varies depending on the volume of the object filled in the storage container. In this paper, we developed a system to monitor the storage in three stages: low, medium and high.

• Journal of Korean Port Research
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• v.9 no.2
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• pp.39-49
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• 1995

Recently, the traffic volume has been greatly increased partly because of high growth rate of domestic and world economy, and partly because of increased transhipment demand resulting from the destruction of Kobe port by earthqwake early this year. So, container facilities in Pusan Port are under serious congestion. The congestion costs in connection with container traffic in Pusan Port is estimated to be 29.3 billion won in 1994. In 1995 the situation is still worsening. PECT has continued to grow annually by 35% in cargo handling exceeding more than 31% of the total container volumes handled in Korea. The BOR of container berths in PECT in 1994 is 75% reflecting extreme congestion in container traffic. The reason for such serious congestion in PECT is the shortage of container handling facilities in comparison with ever-increasing cargo traffic. In order to solve the provisional problem, the shortage of handling capacity, a model developed to optimize the operation of PECT is described and demonstrated. The model minimizes total port costs, including the costs of dock labour, facilities and equipment, ship, containers, and cargo. The object of this study is, through the model results, mainly to determine the optimal combination of berths and cranes under various circumstances and to show that total costs per ship or unit of cargo served can be reduced by increasing the number of cranes per berth and berth utilization above present levels. Eventually, the results obtained with this model in PECT suggest that increase to 3 in the number of cranes per existing berth could reduce the need for major investments in berths and even reduce operating costs.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.244-249
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• 2006

This study examined the growth characteristics of broad-leaved container seedlings of Stewartia pseudocamellia, Tilia manshurica and Chionanthus retusus in relation to the raw material properties of the container medium in a green house for 4 months in order to develop optimum container medium for broad-leaved container seedlings. Among the container media used, the high level of the height growth and root collar diameter growth of broad-leaved container seedlings of Stewartia pseudocamellia, Tilia manshurica, Chionanthus retusus was found in the container media with relatively more cocopeat or peatmoss, and the dry matter production of the aerial part and the subterranean part. Also, concerning physiological characteristics, the photosynthetic rate of broad-leaved container seedlings increased in proportion to the volume of cocopeat and peatmoss in the container media. The effect of container media on the growth of broad-leaved container seedlings needs continuous study on the irrigation and fertilization programs along with the study on physiological characteristics including growth characteristics, biomass production and photosynthesis.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.171-178
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• 2002

At the present time, container transportation plays a key role in the international logistics and the efforts to increase the productivity of container logistics become essential for Korean trucking companies to survive in the domestic as well as global competition. This study suggests an approach for determining fleet size for container road transportation with dynamic demand. Usually the vehicles operated by the transportation trucking companies in Korea can be classified into three types depending on the ways how their expenses occur; company-owned truck, mandated truck which is owned by outsider who entrust the company with its operation, and rented vehicle (outsourcing). Armually the trucking companies should decide how many company-owned and mandated trucks will be operated considering vehicle types and the transportation demands. With the forecasted monthly data for the volume of containers to be transported a year, a heuristic algorithm using tabu search is developed to determine the number of company-owned trucks, mandated trucks, and rented trucks in order to minimize the expected annual operating cost The idea of the algorithm is based on both the aggregate production planning (APP) and the pickup-and-delivery problem (PDP). Finally the algorithm is tested for the problem how the trucking company determines the fleet size for transporting containers.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10a
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• pp.263-269
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• 1998

The forecasting of container cargo volumes should be estimated correctly because it has a key roles on the establishment of port development planning, and the decision of port operating system. Container cargo volumes have a dynamic characteristics which was changed by effect of competitive ports. Accordingly forecasting was needed overall approach about competitive port's development, alternation and information. But, until now, traffic forecasting was not executed according to competitive situation, and that was accomplished at the point of unit port. Generally, considering the competition situation, simulation method was desirable at forecasting because system's scale was increased, and the influence power was intensified. In this paper, considering this situation, the objectives can be outlined as follows. 1) Structural model constructs by System dynamics method. 2) Structural simulation model develops according to modelling of competitive situation by expended SD method which included HEP(Hierarchical Fuzzy Process) And actually, effectiveness was verified according to proposed model to major port in northeast asia.

• Journal of Korean Port Research
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• v.11 no.2
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• pp.157-172
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• 1997

To develop the port productivity and effictiveness, the introduction of the On Dock Operating System in Pusan Container Terminals has to be considered and the present Off Dock CY be closed step by step. This work aims to evaluate the needed CY area in Pusan Port under the On Dock Operating System. This researching flow is as follows. Firstly, estimate total sea-borne container cargo volumes in Korea and distribute them to all container terminals according to the past trends and the planned port development. Secondly, estimate the average period and the average tiers stored at On Dock CY in case of On Dock Operating System. Thirdly caculate the needed CY Area to handle the distributed container cargo volume under the On Dock Operating System. Finally, the following results are obtained. (1) In 1998, opening the Gamman Terminal, 827 thousands cubic meters are insufficient. (2) In $2001\sim2004$, the insufficiency of needed CY Area will be maximized and estimated to be 936 thousands cubic meters in 2001. (3) In $2005\sim2011$, opening the Gadu Terminal, the insufficiency of needed CY Area will be decreased and estimated to be 240 thousands cubic meters in 2011.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.439-451
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• 2023

Purpose - Market structure is crucial to identify as it defines the market states for new and existing container ports to perform within a given region. the study aims to compare the major ports in the Bay of Bengal in the context of Chittagong Port. Design/methodology/approach - For this study, the past 9 years of container volume data have been collected and analyzed through the HHI index, BCG matrix and shift effect analysis. Based on the analysis, this study has found that the Chittagong Port is in an oligopoly competitive market structure. Findings - The findings have shown that port in low market share and low growth in very recent years with the moderately concentrated ports HHI index. The shift effect analysis shows that the container volumes shifted from one port to another in the 2019 and 2020 periods. This study is the pioneer study in the Bay of Bengal region to identify the market structure, analyze market share and growth, and analyze the market concentration. Research implications or Originality - Future recommendations for the port authority is to take advantage of geolocation; attract international; tax exemption, faster clearance process, reduced waiting charges; increasing storage and technological machinery; promoting maritime logistics education; promoting Chittagong tourism; collaboration with other countries. Also, this study can be used as basic data for the establishment of a new supply chain between Korea and Southwest Asia for the Korean government and companies.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4096-4101
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• 2023

Radon is a radioactive gas produced from the uranium-238 series. Radon gas affects public health and is the second cause of lung cancer. The study samples were collected from one area of the city of Jazan, southwest of the Kingdom of Saudi Arabia. The influence of engineering and physical parameters on the emanation coefficient of gas and other gas parameters was studied. Parameters for radon were measured using a CR-39 Solid-State Nuclear Track Detector (SSNTD) through a sealed emission container. The results showed that the emanation coefficient was affected directly by the change in the grain size of the soil. All parameters of measured radon gas have the same behavior as the emanation coefficient. The relationship between particle size and emanation coefficient showed a good correlation. The values of the emanation coefficient were inversely affected by the mass of the sample, and the rest of the parameters showed an inverse behavior. The results showed that increasing the volume of the container increases the accumulation of radon sons on the wall of the container, which increases the emission factor. The rest of the parameters of radon gas showed an inverse behavior with increasing container size. The results concluded that changing the engineering and physical parameters has a significant impact on both the emanation coefficient and all radon parameters. The emanation coefficient affects the values of the radiation dose of an alpha particle.

• Korea Trade Review
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• v.44 no.2
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• pp.51-62
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• 2019

This study predicts the future world seaborne trade volume with econometrics methods using 23-year time series data provided by Clarksons. For this purpose, this study uses simple regression analysis, exponential smoothing method and seemingly unrelated regression model (SUR Model). This study is meaningful in that it predicts worldwide total seaborne trade volume and seaborne traffic in four major items (container, bulk, crude oil, and LNG) from 2019 to 2023 as there are few prior studies that predict future seaborne traffic using recent data. It is expected that more useful references can be provided to trade related workers if the analysis period was increased and additional variables could be included in future studies.