• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.5
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• pp.10-24
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• 2007

In the dissertation, a power conversion system for fuel cell is composed of a PWM inverter with LC filter in order to convert fuel cell voltage to a single phase 220[V]. In addition, new insulated DC-DC converters are proposed in order that fuel cell voltage is boosted to 380[V]. In this paper, it requires smaller components than existing converters, which makes easy control. The proposed DC-DC converter controls output power by the adjustment of phase-shift width using switch $S_5\;and\;S_6$ in the secondary switch which provides 93-97[%] efficiency in the wide range of output voltage. Fuel cell simulator is implemented to show similar output characteristics to actual fuel cell. Appropriate dead time td enables soft switching to the range where the peak value of excitation current in a high frequency transformer is in accordance with current in the primary circuit. Moreover, appropriate setting to serial inductance La reduces communication loss arisen at light-load generator and serge voltage arisen at a secondary switch and serial diode. Finally, TMS320C31 board and EPLD using PWM switching technique to act a single phase full-bridge inverter which is planed to make alternating current suitable for household

• Journal of Bio-Environment Control
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• v.9 no.4
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• pp.237-243
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• 2000

Agricultural machine is currently operated by man power in the greenhouse, which is oppressively hot and humid, and is for a farmer not to work in comfortable circumstances. In the future, agricultural machine will not have to operate by man power, but it will need do by unmanned power. In order to put into the automatic and unmanned operation of agricultural machine, this system was designed and built to move through the fixed path in the greenhouse. This system was composed of guiders(wires), a limit switch, an operating equipment, its software for automatizing a machine in the greenhouse. The guider was connected between the wall pillars, and the equipment was able to slide over the fixed path made of the guider, by rectilinear and rotational motion. A micro mouse was developed with a stepping motor to calculate on the success rate of its operation with the system As might be expected, this system with the micro mouse was moved the moved the paths with a success rate of 100% on the flat plane surface in our laboratory. However, on the sand plane or the other materials plane, the success rate was not better than 80%. If the micro mouse were well operated, the success rate was would be 100%. Based on the results of this research, this system would be expected to operate well on the path made of a simple wire.

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.1
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• pp.87-90
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• 2013

Purpose: Introducing CR (Computed Radiography) system created a process of printing therapy irradiation images and converting the degree of enlargement. This is to increase job efficiency and contribute to work improvement using a computerized method with home grown software to simplify this process, work efficiency. Materials and Methods: Microsoft EXCEL (ver. 2007) and VISUAL BASIC (ver. 6.0) have been used to make the software. A window for each shield block was designed to enter patients' treatment information. Distances on the digital images were measured, the measured data were entered to the Excel program to calculate the degree of enlargement, and printouts were produced to manufacture shield blocks. Results: By computerizing the existing method with this program, the degree of enlargement can easily be calculated and patients' treatment information can be entered into the printouts by using macro function. As a result, errors in calculation which may occur during the process of production or errors that the treatment information may be delivered wrongly can be reduced. In addition, with the simplification of the conversion process of the degree of enlargement, no copy machine was needed, which resulted in the reduction of use of paper. Conclusion: Works have been improved by computerizing the process of block production and applying it to practice which would simplify the existing method. This software can apply to and improve the actual conditions of each hospital in various ways using various features of EXCEL and VISUAL BASIC which has already been proven and used widely.

• Journal of Korea Multimedia Society
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• v.7 no.3
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• pp.368-376
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• 2004

Currently, the package tools and software development kits of Microsoft's Windows Media Technology provides users an environment to write, distribute and play multimedia contents. However, it is very difficult for common users to create a media streaming content using the Windows Media technology, because of its technical hardship. Therefore, we developed an easy-to-use authoring tool for multimedia streaming content which can be used in the Windows Media Technology environment. Our authoring tool is based on the web page templates by which HTML codes can be generated automatically. Using the existing streaming media authoring tool provided by the Microsoft, users have to code the temporal markers and the event script commands directly to the ASF(Advanced Systems Format) files or ASX (ASF Stream Redirector) format files. We developed an easy-to-use interface for insetting temporal markers and the event script commands to the ASF files by simple mouse clicking and dragging to minimize the effort of users for creating multimedia streaming content. In addition, we implemented an ASX file creation wizard that allows users to create ASX format file without coding ASX tags. We also implemented various web page templates where the ASF files and the ASX files can be embedded by just clicking the corresponding templates. The target web pages can be automatically generated from those templates and previewed directly on the web browser at the time of creation.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.4
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• pp.405-414
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• 2010

According to the statistics of SecurityFocus in 2008, client-side attacks through the Microsoft Internet Explorer have increased by more than 50%. In this paper, we have implemented a behavior-based malicious web page detection system and a blacklist-based malicious web page filtering system. To do this, we first efficiently collected the target URLs by constructing a crawling system. The malicious URL detection system, run on a specific server, visits and renders actively the collected web pages under virtual machine environment. To detect whether each web page is malicious or not, the system state changes of the virtual machine are checked after rendering the page. If abnormal state changes are detected, we conclude the rendered web page is malicious, and insert it into the blacklist of malicious web pages. The malicious URL filtering system, run on the web client machine, filters malicious web pages based on the blacklist when a user visits web sites. We have enhanced system performance by automatically handling message boxes at the time of ULR analysis on the detection system. Experimental results show that the game sites contain up to three times more malicious pages than the other sites, and many attacks incur a file creation and a registry key modification.

• The Korean Journal of Air & Space Law and Policy
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• v.19 no.1
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• pp.37-56
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• 2004

As part of the ongoing global process of airlines forming strategic alliances, Korean Air has become a member of the SkyTeam Alliance, while Asiana has joined the Star Alliance. However, as something akin to the Anti-Trust Immunity(ATI) initiative has not been ratified domestically, these two airlines have seen their roles within these strategic alliances significantly reduced. In keeping with its domestic airline liberalization policy the U.S. government has instituted a mechanism through which foreign airlines that join such strategic alliances with their American counterparts can be exempt from the U.S. antimonopoly law. As a result, U.S. airlines have been able to forge wide ranging cooperative relations with foreign airlines, and thus increased their competitiveness within the air transport industry. This study analyzes the applicability of this Anti-Trust Immunity initiative to the domestic environment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.961-964
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• 2013

Arduino is for design based on open source prototyping platform, artist, designer, hobby activists, etc, i has been designed for all those who are interested in the environment construct. Arduino adventage you can easily create applications hardware, without deep knowledge about the hardware. Configuration of arduino using AVR microcontroller ATmage 168, software to action arduino using arduino program, MATLAB, Processing. Arduino is open source base, you can hardware production directly and using shield additionally, the arduino can be combined. Android is open source. Continue to expand through a combination of hardware, Arduino. It name is shield. Be given to the Arduino Uno board to the main board, the shield extends to the various aspects and help can be equipped with more features. The shield on top of the shield can be combined as a kind of shield and Ethernet shield, motor shield, the shield RFID hardware beyond a simple extension can be configured. In this paper, sortware was used for arduino program, hardware was used for arduino Uno board, the additional shield using RFID shield. Configure the hardware to be compatible with this tag combined the 13.56MHz tag SM130.

• Science of Emotion and Sensibility
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• v.6 no.4
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• pp.15-23
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• 2003

Recently, there have been many attempts to develop BCI (brain computer interface) based on EEG (electroencephalogram). Measurement and analysis of EEG evoked by particular stimulation is important for the design of brain wave pattern and interface of BCI. The purpose of this study is to develop a general-purpose system that measures subject's reaction time after audio-visual stimulation which can work together with any other biosignal measurement systems. The entire system is divided into four modules, which are stimulation signal generation, reaction time measurement, evoked potential measurement and synchronization. Stimulation signal generation module was implemented by means of Flash. Measurement of the reaction time (the period between the answer request and the subject reaction) was achieved by self-made microcontroller system. EEG measurement was performed using the ready-made hardware and software without any modification. Synchronization of all modules was achieved by, first, the black-and-white signals on the stimulation screen synchronized with the problem presentation and the answer request, second, the photodetectors sensing the signals. The proposed method offers easy design of purpose-specific system only by adding simple modules (reaction time measurement, synchronization) to the ready-made stimulation and EEG system, and therefore, it is expected to accelerate the researches requiring the measurement of evoked response and reaction time.

• Journal of the Korea Society for Simulation
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• v.15 no.1
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• pp.35-42
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• 2006

Sensor network, that is an infrastructure of ubiquitous computing, consists of a number of sensor nodes of which hardware is very small. The network topology and routing scheme of the network should be determined according to its purpose, and its hardware and software may have to be changed as needed from time to time. Thus, the sensor network simulator being capable of verifying its behavior and estimating performance is required for better design. Sensor network simulators currently existing have been developed for specific hardwares or operating systems, so that they can only be used for such systems and do not provide any means to estimate the amount of power consumption and program execution time which are major issues for system design. In this study, we develop the sensor network simulator that can be used to design and verify various sensor networks without regarding to types of applications or operating systems, and also has the capability of predicting the amount of power consumption and program execution time. For this purpose, the simulator is developed by using machine instruction-level discrete-event simulation scheme. As a result, the simulator can be used to analyze program execution timings and related system behaviors in the actual sensor nodes in detail. Instruction traces used as workload for simulations are executable images produced by the cross-compiler for ATmega128L microcontroller.

• The KIPS Transactions:PartA
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• v.8A no.4
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• pp.479-488
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• 2001

As the SoC designs complexity constantly increases, the simulation that uses their software models simply takes too much time. To solve this problem, FPGA-based logic emulators have been developed and commonly used in the industry. However, FPGA-based logic emulators are facing with the problems of which not only very low FPGA resource usage rate due to the very limited number of pins in FPGAs, but also the emulation speed getting slow drastically as the complexity of designs increases. In this paper, we proposed a new innovative emulation architecture and its software that has high FPGA resource usage rate and makes the emulation extremely fast. The proposed emulation system has merits to overcome the FPGA pin limitation by pipelined ring which transfers multiple logic signal through a single physical pin, and it also makes possible to use a high speed system clock through the intelligent ring topology. In this topology, not only all signal transfer channels among EPGAs are totally separated from user logic so that a high speed system clock can be used, but also the depth of combinational paths is kept swallow as much as possible. Both of these are contributed to achieve high speed emulation. For pipelined singnals transfer among FPGAs we adopt a few heuristic scheduling having low computation complexity. Experimental result with a 12 bit microcontroller has shown that high speed emulation possible even with these simple heuristic scheduling algorithms.