• Journal of Korean Port Research
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• v.2 no.1
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• pp.75-106
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• 1988

As port transport system consists of subsystems such as navigation system, cargo handling system, storage system, inland transport system, and Management and Information system, the productivity of this system is determined by the minimum level of subsystem. From the viewpoint of elaborating the efficiency of integrated system, it is valuable to determine the optimal level of harbour tug boat which is the most important factor of navigation system. This paper treats the optimal amount of harbour tug boat by simulation, and applied to Pusan port. In the course of simulation, an emperical formula is introduced for determining the Horse Power (HP) of tug boat by the ship's gross tonnage (G/T) refering to the cases of various ports of other countries, that is ; $Y=9.96X^{0.6}+569$. X : The gross tonnage of vessel (G/T). Y : The Horse Power (HP) of tug boat. The results of the simulation are summarized as follows ; 1) In 1987, three or four low-powered harbour tug boats, five mid-powered harbour tug boats and four high-powered harbour tug boats are necessary in the mean level. But, five or seven low-powered harbour tug boats, ten mid-powered harbour tug boats and eight high-powered harbour tug boats are necessary lest delay should occur at all. 2) In 1992, 1lee or four low-powered harbour tug boats, six mid-powered harbour tug boats and seven high-powered harbour tug boats are estimated and be necessary in the mean level.

• Journal of Navigation and Port Research
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• v.42 no.2
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• pp.143-152
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• 2018

Currently, there are very few papers that have examined the efficiency of Vietnamese ports. Of those that have, some of them take into account only a few container ports in Northern Vietnam. Others focus on comparing all types of ports in Vietnam with regard to the differences in efficiency scores when applying different methods to evaluate efficiency. However, there is no paper that specifically analyzes the efficiency of Vietnamese container ports throughout the country or that compares Vietnamese container ports with those of other countries in terms of efficiency. In order to provide more accurate and interesting information for container port authorities, in this study, 21 major Vietnamese container ports and seven major Korean container ports are selected and examined with regard to their levels of efficiency in 2016 using data envelopment analysis (DEA). This paper applies both constant return to scale (CRS) and variable return to scale (VRS) to explore the differences among overall technical efficiency, pure technical efficiency, and scale efficiency of the selected container ports. This study also indicate slacks and sets projections for inefficient ports.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.1
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• pp.72-79
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• 2003

Due to the improvements in circuit design technique and manufacturing technique, complexity of a circuit is growing along with the demand for memories with large capacities. Likewise, as a memory capacity gets larger, testing gets harder and testing cost increases, and testing process in chip development gets larger as well. Therefore, a research on an effective test algorithm to improve the chip yield rate in a short time period is becoming an important task. This paper proposes an effective, March C-algorithm based, test algorithm that can also be applied to a dual-port memory since it considers all the fault types, which can be occurred in a single-port as well as in a dual-port memory, without increasing the test length.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.333-344
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• 1999

Currently many studies on the unmanned gantry crane for the automated container terminal are accomplished. This is needed for the development of large scale, automation, high speed, unmanned system and information system in port facility. In order to do efficient container handling job in port yard, the automated handling system is well adapted to the job environments and all-season weather, In order to realize the automatic and unmanned system for container handling job, the required functions and main structure system are studied. The major problems of operation of the conventional gantry crane are that the vibration of gantry structure body is occurred by operation and that high-speed and precision position-velocity control and the capability to dope to the external disturbances caused by the wind, rain, fog and job environments. In this paper, the fundamental study for establishment of the concept and the dynamic modelling of the major sub system of the unmanned gantry crane is presented. These studies are useful for design and manufacturing of the new concept model of the unmanned gantry crane for efficient operation of the automated container terminal.

• Radiation Oncology Journal
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• v.1 no.1
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• pp.29-36
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• 1983

The treatment of tumors along curved surfaces with stationary electron beams using cone collimation may lead to non-uniform dose distributions due to a varying air gap between the cone surface and patient. For large tumors, more than one port may have to be used in irradiation of the chest wall, often leading to regions of high or low dose at the junction of the adjacent ports. Electron-beam arc therapy may elimination many of these fixed port problems. When treating breast tumors with electrons, the energy of the internal mammary port is usually higher than that of the chest wall port. Bolus is used to increase the skin dose or limit the range of the electrons. We invertiaged the effect of various arc beam parameters in the isodose distributions, and combined into a single arc port for adjacent fixed ports of different electron beam eneries. The higher fixed port energy would be used as the arc beam energy while the beam penetration in the lower energy region would be controlled by a proper thickness of bolus. We obtained the results of following: 1. It is more uniform dose distribution of electron to use rotation than stationary irradiation. 2. Increasing isocenter depth on arc irradiation, increased depth of maximum dose, reduction in surface dose and an increasing penetration of the linear portion of the curve. 3. The deeper penetration of the depth dose curve and higher X-ray background for the smaller field sized. 4. If the isocenter depth increase, the field effect is small. 5. The decreasing arc beam penetration with decreasing isocenter depth and the isocenter depth effect appears at a greater depth as the energy increases. 6. The addition of bolus produces a shift in the penetration that is the same for all depths leaving the shape of the curves unchanged. 7. Lead strips 5 mm thick were placed at both ends of the arc to produce a rapid dose drop-off.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.7
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• pp.1218-1224
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• 2000

A half-height waveguide power combiner is designed and analyzed for Ka-band satellite application. The branch line directional coupler is utilized as a power combiner to achieve high port-to-port isolation and low insertion loss. The half height waveguide is adopted to reduce the volume and mass of a power combiner. In this paper a half height waveguide power combiner is designed and analyzed by FDTD and its performance is compared with that of a full-height waveguide power combiner. The designed half-height combiner having optimum order is manufactured and tested. The measurement shows that the designed half-height power combiner satisfies all the performance requirements (insertion loss less than 0.3 dB, reflection loss more than 20dB, port to port isolation more than 20 dB, and port to port phase difference within 5$^{\circ}$) in the satellite communication frequency band of 20.255 GHz to 21.255 GHz.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1695-1705
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• 2016

With the rapid development of global economic and trade, the ports in the North-east Asia region have developed greatly. In such a fierce competition, how to ascertain right evaluation methods to assess the competitiveness of the ports, and make scientific and rational development strategy for upgrading the overall level of competitiveness of ports in North-east Asia, has become the first task for all the ports for coping with the challenges. As China's sustained economic growth of more than 30 years, the economic power and comprehensive national strength has been changed, China's international status has been greatly improved. Also China has achieved remarkable new results in the construction of peripheral diplomacy, and further has consolidated the relationship of countries along the Silk Road Economic Belt. The strong position of RMB in foreign exchange market and the implementation of the strategy of "area" opening to the outside world accelerated economic belt along the silk road in China to the west open pace. On the basis of the SWOT analysis of the Lianyungang Port, combined with the comprehensive and practical port competitiveness evaluation indicators system and competitiveness evaluation method, calculate the competitiveness level of Lianyungang port in East China, and find out the problems must be solved. The development strategies for Lianyungang port under One Belt One Road were suggested.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.159-164
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• 2020

In this study, the flow analysis of air in the inner side of vehicle due to the position on inlet port of air at car was carried out. Under the comfortable condition as the inlet port in which the air flows, it was possible to confirm that the inlets became the upper and middle sides or the forward side of the vehicle. If the air flow is not evenly distributed within the vehicle, the lower position of the vehicle is the lowest condition among all conditions. The results of this study will help to keep the inner state of the vehicle pleasant by adjusting the location of the inlet to suit the passenger's taste or situation. The design and analysis results of this study can be effectively applied at adjusting the location of the inlet at car. By applying the flow analysis according to the inlet port of air at car, this paper is seen as the convergence study that conforms to aesthetic design.

• Journal of the Korean Institute of Navigation
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• v.23 no.4
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• pp.43-61
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• 1999

To ensure ship's safety and preserve the marine environment from ship, IMO(International Maritime Organization) has been making much efforts. Nevertheless there are still many possibilities threatening ship's safety and the marine environment. Many vessels navigate at sea in lack of standard required by the International Convention relevant to ship's safety and the protection of marine environment. Even though the administration is responsible for perfect and continuous control for safety of ship, it cannot has jurisdiction over ships hoist its flag reasonably at all times. So the Port State has strengthened the Port State Control(PSC) activity as one step of eliminating sub-standard vessels. In the light of the fact that mentioned above, this study deals with PSC activity in Korea and port of Pusan. Total 582 ships, inspected in port of Pusan from 1st January 1998 to 30th September 1999, were analyzed in various aspect and extracted results as follows : \circled1 The inspection rate in Korea was much lower than the other states taking part in Tokyo MOU, \circled2 For flag state, the ships belong to flag of convenience(FOC) had much more deficiencies than non-convenience flag ships, \circled3 For ship type, 39 number of general dry cargo ship were detained at Pusan with serious deficiencies, \circled4 For deficiency item, the items such as life saving appliances, safety in general, navigation, load lines and fire-fighting appliances were occupied over 71.7% of total number of deficiencies, \circled5 In Asia-Pacific region, Korea was one of flags with detention percentages exceeding 3-year(1996~1998) rolling average detention percentage. Average detention rate of Korean vessels was 6.73% which was over 0.24% of average detention rate(6.49%) in Asia-Pacific region. These results may reflect to improve the performance of PSC inspection for foreign vessels and are useful for preparing PSC inspection for ocean-going ships registered in Korea.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.127-136
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• 2017

The aim of this study is using DEA-CCR, BCC, and Malmquist analysis to determine the efficiency and productivity of Korean automobile ports. We analyzed eight Korean automobile port terminals, using the number of workers and size of ports as input variables and the number of processed car as output variables. An efficiency analysis of the eight automobile port terminals for the four-year span from 2013 to 2016 revealed efficiency levels of 1 for the CCR, BCC, and the scales for Ulsan port and the Gwangyang port terminal, indicating efficient operation of the terminals. As a result of benchmarking analysis, Gunsan port 1, 2 terminal, Incheon port, Pyeongtaek Dangjin 2 terminal should benchmark Busan Port and Ulsan Port. Conversely, Malmquist analysis showed a slight increase in the production volume from 2013 to 2015, but a decline to 1 or less from 2015 to 2016. In the case of TECI the technology was confirmed as effective at 1 or more from 2014 to 2015. The TCI value was 0.87 for the period from 2015 to 2016. During this period, the TCI index of all terminals was less than 1.