• Journal of the Korean Society for Aviation and Aeronautics
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• v.12 no.2
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• pp.43-58
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• 2004

Up-to-date cargo transport system, CVO(Commercial Vehicle Operations) is the system to manage efficiently cargo distribution as providing at real time the information of cargo location and situation through ITS and GPS technology. In this paper, we proposed the Gate Automation System of harbors among AEI/AVI. To implement his system, we use the DSRC/RFID(Dedicated Short Range Communication / Radio Frequency IDentification) which adopts an wireless communication between RSE(Road-side Equipment) and OBE(on-Board Equipment) on a vehicle. When constructing the Gate automation system of harbors, the business application ability are reviewed practically and the logistics facilities to be constructed in the near future may use this project results according to the international standard and it could help complete integrated logistics system.

• The KIPS Transactions:PartA
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• v.10A no.5
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• pp.513-518
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• 2003

The quantity of container transportation of the world habors is constantly increasing by 8.8 per year until 2011. Present port facilities will not satisfy it. So facility expansion is necessary. Because the processing cost in the harbor becomes to 30% of total transportation expense, major pors inthe world are making an effort in the automation facilities to solve the problems of higher labor costs and indufficient labor and to maximize the efficiency of the work and use of the land. Especially, the automation of the gate, which is the place of cargo's appearance and disappearance, the node which creates the information, is now rising as the important issue. In this study suggest more efficient design for port gate automation. First, calculate scale of gate complex, and compare of 1 step gate and 2 step, and optimal design for automated operation method of gate process.

• Journal of Power Electronics
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• v.15 no.5
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• pp.1402-1408
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• 2015

A MOSFET's gate driver based on magnetic coupling is investigated. The gate driver can meet the demands in applications for wide range of duty cycles and high frequency. Fully galvanic isolation can be realized, and no auxiliary supply is needed. The driver is insensitive to the leakage inductor of the isolated transformer. No gate resistor is needed to damp the oscillation, and thus the peak output current of the gate driver can be improved. Design of the driving transformer can also be made more flexible, which helps to improve the isolation voltage between the power stage and the control electronics, and aids to enhance the electromagnetic compatibility. The driver's operation principle is analyzed, and the design method for its key parameters is presented. The performance analysis is validated via experiment. The disadvantages of the traditional magnetic coupling and optical coupling have been conquered through the investigated circuit.

• Journal of Navigation and Port Research
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• v.41 no.3
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• pp.119-126
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• 2017

As container vessels get larger, container terminals are also likely to grow. The problem that arises is that the growing volume should be handled in the same amount of time as before. Container terminals are introducing an automation system in order to overcome the limitations of existing manual methods and to continuously reduce operating expenses. Because, Manual handling of carrying containers gate in and out of terminals causes inaccurate data, which results in confusion. An alternative is for containers to be labeled with barcodes that can be scanned into a system with a scanner, but this takes quite a long time and is inconvenient. A RFID system, also known as a gate automation system, can solve these problems by reducing the time of gate management with a technology that detects number identification plates, helping operators more efficiently perform gate management work. Having said that, with this system, when container damage is detected, gate operators make and keep documents manually. These documents, which are insufficient evidence in proving container damage, result in customer claims. In addition, it is difficult for gate operators and other workers to manage containers, exposing them to danger and accidents. This study suggests that if an automation system is introduced at gates, containers can be managed by a video storage system in order to better document damage The video system maintains information on container damage, allowing operators the ability to search for videos they need upon customer request, also allowing them to be better prepared for customer claims. In addition, this system reduces necessary personnel and risk of accidents near gates by integrating a wide range of work.

• Advances in nano research
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• v.15 no.3
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• pp.263-275
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• 2023

The electron transport properties of Y-type zigzag branched carbon nanotubes (CNTs) are of great significance for micro and nano carbon-based electronic devices and their interconnection. Based on the semi-empirical method combining tight-binding density functional theory and non-equilibrium Green's function, the electron transport properties between the branches of Y-type zigzag branched CNT are studied. The results show that the drain-source current of semiconducting Y-type zigzag branched CNT (8, 0)-(4, 0)-(4, 0) is cut-off and not affected by the gate voltage in a bias voltage range [-0.5 V, 0.5 V]. The current presents a nonlinear change in a bias voltage range [-1.5 V, -0.5 V] and [0.5 V, 1.5 V]. The tangent slope of the current-voltage curve can be changed by the gate voltage to realize the regulation of the current. The regulation effect under negative bias voltage is more significant. For the larger diameter semiconducting Y-type zigzag branched CNT (10, 0)-(5, 0)-(5, 0), only the value of drain-source current increases due to the larger diameter. For metallic Y-type zigzag branched CNT (12, 0)-(6, 0)-(6, 0), the drain-source current presents a linear change in a bias voltage range [-1.5 V, 1.5 V] and is symmetrical about (0, 0). The slope of current-voltage line can be changed by the gate voltage to realize the regulation of the current. For three kinds of Y-type zigzag branched CNT with different diameters and different conductivity, the current-voltage curve trend changes from decline to rise when the branch of drain-source is exchanged. The current regulation effect of semiconducting Y-type zigzag branched CNT under negative bias voltage is also more significant.

• Journal of Power Electronics
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• v.18 no.1
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• pp.23-33
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• 2018

Silicon Carbide (SiC) MOSFET belongs to the family of wide-band gap devices with inherit property of low switching and conduction losses. The stable operation of SiC MOSFET at higher operating temperatures has invoked the interest of researchers in terms of its application to high power density (HPD) power converters. This paper presents a performance study of SiC MOSFET based two-phase interleaved boost converter (IBC) for regulation of avionics bus voltage in more electric aircraft (MEA). A 450W HPD, IBC has been developed for study, which delivers 28V output voltage when supplied by 24V battery. A gate driver design for SiC MOSFET is presented which ensures the operation of converter at 250kHz switching frequency, reduces the miller current and gate signal ringing. The peak current mode control (PCMC) has been employed for load voltage regulation. The efficiency of SiC MOSFET based IBC converter is compared against Si counterpart. Experimentally obtained efficiency results are presented to show that SiC MOSFET is the device of choice under a heavy load and high switching frequency operation.

• Journal of the Korea Society of Computer and Information
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• v.6 no.2
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• pp.58-64
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• 2001

The quantity of container transportation of the world harbors is constantly increasing by 8.8％ per year until 2011. present port facilities will not satisfy it. So facility expansion is necessary. Because the processing cost in the harbor becomes to 30％ of total transportation expense, major ports in the world are making an effort in the automation facilities to solve the problems of higher labor costs and insufficient labor and to maximize the efficiency of the work and use of the land. Especially, the automation of the gate, which is the place of cargo's appearance and disappearance, the node which creates the information. is now rising as the important issue. In this study suggests more efficient design for port gate automation.

• The Journal of the Korea Contents Association
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• v.6 no.2
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• pp.1-8
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• 2006

In this paper, we address to develop a port container management system using RFID, which is one of the main technologies in ubiquitous. Our system is designed and implemented based on the following technologies: a port gate automation using RFID for container identification, web programming for both communication of the gate and deposit/delivery of a container, and wireless embedded router technology for both port container network platform and cram terminals. The developed system using RFID will be expected to use in main part of the port logistic management system aimed to the intelligent port.

• Journal of Korean Port Research
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• v.14 no.3
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• pp.313-319
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• 2000

In this paper, we proposed the model of wireless communication for ACTS using DSRC and the DSRC system for T/C. The proposed wireless communication model is how to join with DSRC and other wireless communication in port. The DSRC system for T/C is the first application to the unit of port Facilities Automation on stacking area. The DSRC system is communicated between OBE and RSE using 5.8Hz ISM band frequency. The previous works of DSRC applications are gate automation. In these cases, the road trackers are difficult to obtain information of the port in the stacking area. So we used the DSRC for the wireless communication for the port Facilities Automation. Using DSRC, the load trackers obtain more information in the port and contacts to ITS on back-roads of port. The proposed communication system is serviced to reelection of port statistics.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.1
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• pp.49-54
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• 1995

Three types of floating-type automatic inlet were developed for the purpose of reduc- ing farmer's working hours required for water management and saving irrigation water. The point of automation is to use a float within the inlet which is floated and sinked by the ponding depth of paddy field, Thus opens and closes the control gate of irrigation. Suitability of each inlet may depend on production cost, applicability to paddy field condi- tions, and feasibility to farmers, etc. The first model was composed of three parts : chamber for irrigation control gate, chamber for float controlled by ponding depth, and connection bar between the two parts. It was designed to open and close the control gate gradually as the ponding depth drops and rises to a certain level. The second model was designed to improve the weak point of the first model which is the imperfect-closing of gate when it approaches to the end of ir- rigation. A switch-spring was equipped above the connection bar for perfect opening and closing of gate when the ponding depth reaches to a certain level. The third model was designed by combining the two chambers, that is, cut in halves the inlet volume of the above two models. Magnets were equipped above the float for perfect opening and closing gate. The functional experiment for three developed inlets was successfully carried out and the rating curves were derived.