• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.1-20
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• 2009

A survey to pallet users was conducted in an aspect of the efficiency and benefit. The questionnaire identified the preference about the main variables such as price, size, conformity, material, which are the criteria of the users' choice. staffs in the capital region was selected as respondents and Cluster Analysis and Simulations was carried out with Conjoint Analysis. The result shows that the variables of material and conformity between facilities and products were more important than the variable of size. The respondents prefer the pallets with a various range of products because warehouses should keep a range of products under various condition of temperature. In accordance, the companies that provide a pallet pool service should set up individual marketing strategy by a type of customers so as to maximize the competitiveness in domestic or international markets. Furthermore, supplying standardized pallets should be consistent with the standardization not for individual logistics units, but for whole logistic systems. To achieve this, it requires the compatibility amongst a range of logistics activity participants by their characteristics.

• Fire Science and Engineering
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• v.33 no.4
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• pp.112-120
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• 2019

Benzene is a class 4 hazardous material according to the Act on the Safety Control of Hazardous Substances. This study qualitatively evaluated the damage size of a "toxic" accident and "pool fire" accidents based on benzene in a virtual scenario of a fire and leakage accident during unloading at a port facility. The KORA program was used as an evaluation method, which is supported as a universal program by the National Institute of Chemical Safety. The range of damage effects of a benzene-induced fire and leakage accident was predicted. In the case of toxic damage range, the accident's damage effect range for the "worst case scenario" was reduced by up to 5.11% with a decrease in the size of the leakage hole. In the case of the leakage time, the damage effect range increased to 145.12% with a 10 min leakage time compared to that of a 5 min leakage time and went up to 20 min (212.29%) with a 20 min leakage time. In the case of pool-fire-induced damage, the damage effect range by radiant heat in the "worst case scenario" was 228.8 m in radius from the center of the handling facility. In the "alternative scenario," the damage effect range by radiant heat was reduced by up to 8.26% compared to that in the "worst case scenario" since the size of the leakage hole was decreased by reducing the cross-sectional area of the pipe.

• Journal of IKEEE
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• v.9 no.1 s.16
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• pp.19-30
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• 2005

Packet classification is defined as the action to match the packet with a set of predefined rules. One of classification is to use Ternary Content Addressable Memory hardware search engine that has faster than other algorithmic methods. However, TCAM has some limitations. One of them is that TCAM can not perform range matching efficiently. A range has to be expanded into prefixes to fit the boundary. In general, the number of expansion could be up to 2w-2, where w is the width of the field. For example, if two range fields with 16 bits are used, there could be up to $30\;{\times}\;30\;=\;900$ expansions for a single rule. In this paper, we describe the novel algorithm for converting range matching rules into TCAM entry efficiently. The number of maximum entry is 2w-4 when using the algorithm. Furthermore, it has also benefit about the negation range. In the result of experimentation, the new scheme practically reduces 14 percent in case that searched fields are source port and destination port number.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.239-244
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• 2004

A range of problems rave risen as the results of the obligated charter service. Constant lack of operation improvement compared to regular routes and lower quality service are results of business practice by the service providers. lherefore, this study executed an actual research using AHP to present a method for improvement by investigating remote island clnrter service providers. Result shows tint the desirable method is to implement operation evaluation system to induce service providers to consistently put efforts on the operating system development.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.101-103
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• 2000

Research for the synthesis of high-temperature polymers by the photochemical method has been carrying out. The use of cheap and available compounds (viz. benzene, its alkyl, aryl and halogen substitutes, furan and maleic anhydride) subject to ultra violet irradiation resulted in a single stage quantitative yield of about 40 new polymers: polyimide films, enamel insulation, molding materials. At present experimental & industrial lots of wire have been produced. Polymer insulation possesses temperature exploitation range (from -l00$^{\circ}C$ to +300$^{\circ}C$ ) without significant changing of properties. As a result, new polyimide lacquers for production of a wide number of technical articles, such as polyimide films, fibres, enamel-wires, press-materials have been synthesized. An application field of the polyimides in membrane technology, printing plate and optic electronics manufactures has been outlined.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.219-225
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• 2000

The major movement block of the containers have range between apron and designation points on yard in container terminal. The yard tractor operated by human takes charge of its movement in conventional container terminal. In automated container terminal, AGV(Automated Guided Vehicle) has charge of the yard tractor's role and the navigation path is ordered from upper level control system. The automated container terminal facilities must have the docking system to guide landing line to have high speed travelling and precision positioning. The general method for docking system uses the vision system with CCD camera, infra red, and laser. This paper describes the detection of AGV's position and orientation using laser slit beam to develop docking system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.17-20
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• 2000

This study is about a retrograde triple well employed in the Cell tr. of next DRAM and flash memory. triple well structure is formed deep n-well under the light p-well using MeV ion implantation. MeV P implanted deep n-well was observed to show greatly improved characteristics of electrical isolation and soft error. Junction leakage current, however, showed a critical behavior as a function of implantation and annealing conditions. {311} defects were observed to be responsible for the leakage current. {311} defects were generated near the R$\sub$p/ (projected range) region and grown upward to the surface during annealing. This is study on the defect behavior in device region as a function of implantation and annealing conditions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.305-307
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• 2016

The purpose of this paper is to determine the optimal values of the gain parameters used in the tracking module for a highly dynamic warship. The algorithm of the tracking module uses the ${\alpha}-{\beta}-{\gamma}$ filter to compute accurate estimates and update the state variables, that is, positions, velocity and acceleration. The filtering coefficients ${\alpha}$, ${\beta}$ and ${\gamma}$ are determined from set values of the damping parameter, ${\xi}$. Optimization is achieved by plotting a range of the damping parameter ${\xi}$ against the corresponding residual error and then selecting the best value of ${\xi}$ with the minimum residual error. Optimal values of the smoothing coefficients are subsequently computed from the selected damping parameter, ${\xi}$.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.16
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• pp.245-264
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• 2001

This study aims to evaluate and compare the service quality level of major container ports in Asia. Seven factors are used to evaluate the port service qualities; informational assistance, location, processing speed, facilities, port operation, costs, and user convenience. Ten ports are selected as a sample; Singapore, Kobe, Osaka, Kaohsiung, Hong Kong, Shanghai, Tianjin, Busan, Kwangyang and Inchon. ANOVA and Duncan's multiple range test are used to analyze the survey data. The empirical results shows that, in general, Korean ports provides poorer service qualities than Singapore, Hong Kong, Kobe, and Osaka. Furthermore, the service quality levels of Korean ports are similar to or no better than Chinese ports.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.459-464
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• 2004

In this paper, an autonomous navigation system for autonomous guided vehicles (AGVs) operated in an automated container terminal is designed. The navigation system is based on the sensors detecting the range and bearing. The navigation algorithm used is an interacting multiple model (IMM) algorithm to detect other AGVs and avoid other obstacles using informations obtained from multiple sensors. As models to detect other AGVs (or obstacles), two kinematic models are derived： Constant velocity model for linear motion and constant speed turn model for curvilinear motion. For constant speed turn model, an unscented Kalman filter (UKF) is used because of drawbacks of the extended Kalman filter (EKF) in nonlinear system. The suggested algorithm reduces the root mean squares error for linear motions, while it can rapidly detect possible turning motions.