• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.809-812
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• 2005

In this work, a new method for extracting substrate parameters of RF MOSFETs based on 3-port measurement is presented using device simulation. A T-type substrate resistance network is used. 3-port Y-parameter analyses were performed on the equivalent circuit of RF MOSFETs. All the components in the RF MOSFETs when the device is turned off were extracted directly from the 3-port device simulation data. The small-signal output admittance $Y_{22}$ can be well modeled up to 40 GHz. From the 3-port simulation and modeling results, it was verified that the proposed equivalent circuit and parameter extraction method was more accurate than the single substrate resistance model.

• 한국해양공학회지
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• 제30권3호
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• pp.177-185
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• 2016

In this study, the model developed by Hong (2012) was modified to describe the consecutive docking/undocking situation and was also applied to investigate the effect on seawater circulation in Busan port by consecutive docking/undocking at the connecting bridge of Busan port. Numerical experiments for various docking/undocking cases were performed by dumping the initial concentration within Busan Port and indicated that the concentration in Busan port becomes steady state without numerical wiggles after sufficient time (at least 20 or 30 days). In addition, it was found that the seawater circulation under ship docking was slightly reduced in comparison with that under ship undocking, and the approach time to the target concentration under all the docking cases increased in comparison with the undocking case.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 춘계학술대회논문집
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• pp.47-56
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• 2000

In this study, as the preliminary step for developing an unmanned vehicle to deliver a container-box, we designed and implemented Automatic Guided Vehicle(AGV) Simulator for the purpose of Port Facilities Automation. It is preferable to research the intelligent AGV for delivery all day long. For complementing AGV simulator driving, we used multiple-sensor systems with vision, ultrasonic, IR and adapted the high-speed wireless LAN that satisfies the IEEE 802.11 Standard for bi-directional communication between main processor in AGV and Host computer. Here, we mounted on bottom frame in AGV Pentium-III processor, which combine and compute the information from each sensor system and control the AGV driving, and used the 80C196KC micro-controller to control the actuating and steering motors.

• 한국항공운항학회지
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• 제15권4호
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• pp.38-44
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• 2007

This paper describes the structural safety of solid fuel in the Hybrid Rocket Motor (HRM). Hybrid rocket combustion has the distinct regression characteristics which include the process of thermal pyrolysis and fuel vaporization. Most of all, this regression characteristics would structurally affect the strength of the fuel having a multi-port configuration, and even may cause the breaking from the fuel grain. This problem would probably influence the performance and operating safety of HRM. Therefore, for the safe operation of HRM, the critical port radius which determines the structurally safe region was discussed from the heat analysis of the solid fuel.

• 한국정보시스템학회:학술대회논문집
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• 한국정보시스템학회 2001년도 추계학술대회 발표논문집:차세대 전상거래 시대의 비즈니스전략
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• pp.14-30
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• 2001

At present, EDI system is indispensable process in Port and e-logis industry. Using EDI system service has been variably applicable Client/Server system base on 2-Tier, Web EDI and skill oriented distribution object. Up to date, EDI System has been Closed. Moreover it raised several points on User. For settling the problem, A study make progress with Web EDI system, XML/EDl system, distribution object technology based on 3-Tier. This Study produce several EDI system and Service. With a Result of study as the central figure, All kinds of System and Service make a comparative study synthetically in port and e-logis industry. As a result of Study, this paper make an Model Construction Planning for estimating the Port EDI System.

• 한국항만학회지
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• 제14권2호
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• pp.199-207
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• 2000

In this study, as the preliminary step for developing an unmanned vehicle to deliver a container-box, we designed and implemented Automatic Guided Vehicle(AGV) Simulator for the purpose of Port Facilities Automation. It is preferable to research the intelligent AGV for delivery all day long. For complementing AGV simulator driving, we used multiple-sensor systems with vision, ultrasonic, IR and adapted the high-speed wireless LAN that satisfies the IEEE 802.11 Standard for bi-directional communication between main processor in AGV and Host computer. Here, we mounted on bottom frame in AGV Pentium-III processor, which combine and compute the information from each sensor system and control the AGV driving, and used the 80C196KC micro-controller to control the actuating and steering motors.

• Journal of Power Electronics
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• 제19권5호
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• pp.1278-1288
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• 2019

A DC-DC Non-Isolated Three-Port Cuk-Cuk (NI-TPCC) converter for interfacing renewable energy sources (RESs) such as Fuel Cell (FC) and Photovoltaic (PV) energy with a DC load is presented in this paper. It features single-stage power conversion from both of the input ports to the load port. The proposed NI-TPCC converter is designed based on the classical Cuk converter. The operational modes and power flow are analyzed in the continuous conduction mode (CCM), and the relationships among the port voltages are derived. Continuous currents in all three ports with less ripple enhance the performance of a fuel cell and its operating life. Furthermore, the output inductor is shared with both of the input ports, which reduces the number of active and passive components. The effectiveness of the designed NI-TPCC converter has been validated through simulation and experimental results.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2010년도 춘계학술대회
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• pp.448-452
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• 2010

전통적인 항로표지는 등광(등명기)에 의존하여 항로 및 위험물을 표시함으로써 통항선박의 안전을 확보하여 왔으나, 울산항을 비롯한 전국 무역항에서 입지조건이 유리한 항만배후단지가 개발됨에 따라 항만배후광이 증가하였고 항로표지의 야간시인성이 현격하게 떨어지는 현상이 발생하였다. 또한, 전국 무역항에서는 채선율 저감을 통한 항만 운영율 향상을 위하여 야간 입출항 제한규모를 단계적으로 상향하고 있어 이에 대비한 통항선박의 안전확보방안 마련이 시급히 요구되고 있는 실정이다. 이에 항행원조시설인 등대 및 등표 등에 등탑직적조명방식(LED논네온 등)을 비롯한 고광력 등명기 등이 적용되었고, 상대적으로 시인성이 떨어지는 등부표에는 시인성 향상과 선위결정이 용이하도록 LED발광번호판을 개발하여 적용한 결과, 항만 이용자들로부터 호평을 받고 있으며 앞으로도 항만배후광 극복을 위한 항로표지의 발전은 계속되어야 할 것이다.

• Journal of Chest Surgery
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• 제48권6호
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• pp.387-392
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• 2015

Background: The aim of this study was to evaluate the feasibility of single-port video-assisted thoracic surgery (VATS) in the treatment of secondary spontaneous pneumothorax (SSP). Methods: Twenty-four patients who were scheduled to undergo single-port VATS for SSP were studied. The medical records of the patients were retrospectively reviewed. The mean follow-up duration was $26.1{\pm}19.8$ months. In order to evaluate the feasibility of single-port VATS for SSP, the postoperative results of single-port VATS (n=15) in patients with emphysema were compared with those of emphysematous patients who underwent three-port VATS (n=15) during the study period. Results: Single-port VATS was feasible in 19 of 24 patients (79.2%), while an additional port was needed in five patients. In the single-port VATS patients, the median operation time, duration of chest tube drainage, and hospital stay were 84.0 minutes, one day, and two days, respectively. Postoperative complications included prolonged chest tube drainage for more than five days (n=1), wound infection (n=1), and vocal fold palsy (n=1). No recurrence of pneumothorax was observed during the follow-up period. The median operation time, duration of chest tube drainage, and hospital stay of the emphysematous patients who underwent single-port VATS were shorter than those who underwent three-port VATS group (p<0.05 for all parameters). Conclusion: Single-port VATS proved to be a feasible procedure in the treatment of patients with secondary spontaneous pneumothorax.

• 한국항해학회지
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• 제11권1호
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• pp.39-65
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• 1987

Since the middle of 1950's, containerization has been rapidly spread over the world in virtue of great merits providing to interensts, and the fundamental changes in port management and prot operations are resulted. As the container terminal is a complex system which is consisted of various subsystems, the treatment for improving the productivity is required in a comprehensive fashion, both in each of its parts and as an integrated system. This paper aims to make an intensive analysis of the Busan Container Terminal system, especially focusing on its subsystems such as ship operation system, storage system and transfer system. First of all, the intrinsic capacity of various subsystems is calculated and it is checked whether the current operation is being performed effectively through the formal analysis. Secondly, the suggestion is presented to improve the operation by considering the throughput that the port of Busan will have to accept in the near future. The results are as follows; 1) As the inefficiency is due to the imbalance between various subsystems at Busan terminal, transfer equipment level must be up to 31% for straddle carrier and 67% transfer crane above all. 2) The yard capacity must be increased by reducing the free dwell time of containers in order to accept the traffic volume smoothly in the near future. 3) The better way to reduce the port congestion is to change berthing rule from the FIFP to the Pre-allocated system by considering the ship arrival pattern.