• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.5
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• pp.521-526
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• 2020

Airfield pavements, such as runways and taxiways, are essential for smooth take-off and landing of fixed-wing aircraft and are the most important installation for the military to carry out air operations during wartime. Therefore, in wartime, it is necessary to reduce the damage to these installations and repair them in the shortest possible time. Recently, the pattern of attack is changing from the use of conventional high explosive which is to create large craters to the use of multiple warheads weapon system which is to effectively attack enemy's airfields but unrelated to accuracy. Hence in this study, through identifying the specification and composition of multiple warheads weapon system, we checked the protection performance and damage patterns of the pavement when explosion occurred on the installed military runway and taxiway by the multiple warheads weapon system. And The multiple warheads weapon systems is able to cause extensive damage but the destructive power of each warhead is not as great, so I would like to propose an airfield pavement design plan for minimal protection against such attacks.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.1102-1109
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• 1993

This paper describes the research and development of Walking Tractors and Tillage Implements for Phase I (1991-1992) . The project consists of : (1) the study and need for the development of the walking tractors for Thailand and other Southeast Asian countries ; (2) the comparison in the use of the walking tractors and their transmission systems that are made in Thailand and aborad : and (3) the design of future walking tractors for Asian farmers in developing countries. The design of the walking tractors is concentrated to provide the ease to farmers, especially the elderly and female which will play an important role in the future agriculture of Thailand due to the lack of manpower. In addition , the design of the walking tractors is also aiming for small-scale farmers, the majority that have limited land capital. The walking tractors consist of several components but the most important one is the " Transmission System" . Thus, the research is concentrated in the devel pment an design of the a new transmission system. The new machine , currently developed, is named after the Chulalongkron University as " Chular Walking Tractor " , model SPJS -60. The tractor uses a 6-7 horsepower diesel engine with three forward gears and one reverse gear. The tractor also uses the latest gearing technology so called planetary gearing system with steering clutches system that never been used in any earlier model. The advantages of the planetary gearing system are : (1) the final drive gear can be small, and can be designed to provide higher strength with less wearing resistance, (2) the system eliminates a shaft which is used in other systems, thus reduces the weight and the manufacturing cost . Furthermore, the Chular Walking Tractor has an additional power take off shaft that can be used or linked with other standard agricultural implements.

• Journal of Advanced Navigation Technology
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• v.19 no.5
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• pp.458-463
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• 2015

This paper suggests detection system for the movement of patient on bed based on IEEE802.15.4 by using pressure pad and guard sensor. The system is designed to detect ordinary activities of patients on bed as well as patients' falling from the bed while sleeping at night. The node that is installed at bed sends data to gather when the pressure pad and sensor of guard detect patients' activities and falling. These data sent to gather are transmitted to monitor at help desk by TCP/IP communication. To remove unnecessary data that occurred due to switch chattering during tossing and turning, timer of MCU is used. Also, Communication module can change transmission power to apply this system to various environments of hospital room. Therefore, the nurse can take care of patients on bed in real time with data about patients' conditions.

• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.511-518
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• 2016

RAPCON non only controls landing/take-off procedures but also approaching air traffics within 60-70 NM range of air force base. This paper, first of all, tries to research the failure rate per operation hours, mean time between failure (MTBF) of RAPCON according to six blocks such as interrogator, receiver, power unit, display unit, data process unit and antenna. In addition, this paper estimates the maintenance cost over next 10 months based on 50 monthly maintenance cost data. Considering the maintenance cost data from RAPCON which has been used over designed service life span, it is no doubt the forecasted data proved the monthly cost would go up incrementally during the rest of economic life of the facility. Such research result is also proven to be the same with the result of bathtub curve data during operating life.

• Health Policy and Management
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• v.18 no.4
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• pp.85-110
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• 2008

In this study, we explore the long-term demand forecasting of high-price medical equipments based on logistic and Bass diffusion model. We analyze the specific pattern of each equipment's diffusion curve by interpreting the parameter estimates of Bass diffusion model. Our findings are as follows. First, ultrasonic imaging system, CT are in the stage of maturity and so, the future demands of them are not too large. Second, medical image processing unit is between growth stage and maturity stage and so, the demand is expected to increase considerably for two or three years. Third, MRI is in the stage of take-off and Mammmography X-ray system is in the stage of maturity but, estimates of the potential number of adopters based on logistic model is considerably different to that based on Bass diffusion model. It means that additional data for these two equipments should be collected and analyzed to obtain the reliable estimates of their demands. Fourth, medical image processing unit have the largest q value. It means that the word-of-mouth effect is important in the diffusion of this equipment. Fifth, for MRI and Ultrasonic system, q/p values have the relatively large value. It means that collective power has an important role in adopting these two equipments.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.6
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• pp.468-477
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• 2014

In this research, how a solar powered HALE (high altitude long endurance) UAV (Unmanned Aerial Vehicle) can climb and reach mission altitude, 18km, starting from the ground using only solar energy. A glider type aircraft was assumed as a baseline configuration which has wing area of $35.98m^2$ and aspect ratio of 25. Configuration parameters, lift and drag coefficients were calculated using OpenVSP and XFLR5 that are NASA open source programs, and climb flights were predicted through energy balance between available energy from solar power and energy necessary for a climb flight. Minimum time climb flight was obtained by minimizing flight velocities at each altitude and total time and total energy consumption to reach the mission altitude were predicted for different take off time. Also, aircraft moving distances due to westerly wind and flight speed were calculated.

• The Korean Journal of Financial Management
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• v.1 no.1
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• pp.119-131
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• 1985

Although Korea is short of capital technology, and natural resources, she has achieved an outstanding progress by the export-drive policies by Korean government and the creative endeavor of Korean firms. As a result of that, Korean economy and enterprises are in the same file of newly industrialized countries and Korea is ready for an economic take-off as a developed country. But in the early 1980s, each country strengthens protective trade theory and resources nationalism, and this has a great influence on the field of international trade environment. In spite of that, to continue the same high development as that of the past. Korea must try to secure and find export markets, solve trade barriers, make sure of the long-term security of resources, develop technology, and strengthen economic cooperations. To satisfy these desires by 2000s, we must try to make Korean enterprises have the global competitive power and them grow strongly among world wide firm through capital and technology accumulated during the passed years, and to do so, there must be a foreign production and marketing management, too, this can be achieved only through foreign overseas direct investment. This investment has various forms, to say, verifical integrated, horizontal integrated. conglomerate integrated forms, and the amount of investment in each country from 18 century to today reaches 500 billion dollars. This investment is done by strategic, behavioral economic, and financial motives. So I am going to approach the fields of like these; in spite of the differences among political, economical, caltural, and social systems, and many risk compared with domestic enterprises, why do Korean firms witsh to transfer the productive facilities to overseas countries and run them there? What is the comparative advantage of foreign direct investment compared with domestic investment ?. why is the factor of comparative advantage transferred through foreign direct investment?, what is the motive of foreign overseas direct investment?, and last the ownership-specific factors and the theory of internalization, and the location specific factors were analysed chiefly. But in consideration of the given condition in Korea, Korean overseas direct investment must be propelled rationally on the basis of the above mentioned theory.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.589-597
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• 2015

Wave energy harvesting system using OWC(Oscillating Water Column) and MB (Movable Body) attached at the caisson breakwater was studied. This system was suggested to maximize wave energy extraction using resonant phenomena of oscillating water column and buoy in wave channel (Park et al., 2014). Not only incident waves but also reflected waves from the breakwater can be used as sources of exciting force for harvesting wave energy efficiently. Using Galerkin finite model based on the linear wave theory (Park, 1991), the performance of the system was evaluated for various damping ratios of power take off system. Numerical results show that the proposed system is excellent in efficiency compared with that of conventional system and the performance of the system is governed by the resonance of oscillating water column in the wave channel. In addition, the additional efforts to minimize viscous damping was found to be necessary because viscous damping occurring in the channel and around the moving buoy is significant in generation efficiency.

• Journal of Astronomy and Space Sciences
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• v.19 no.3
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• pp.215-224
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• 2002

This paper describes EGSE design for the small satellite such like KOMPSAT-2 satellite. Recent design trend of small satellite and EGSE is to take short development time and less cost. For this purpose, the design for KOMPSAT-2 satellite and EGSE are not much modified from KOMPSAT-1 heritage. It means that it is able to be accommodated the verified hardware and software modules used in KOMPSAT-1 satellite program if possible. The objective of EGSE is to provide hardware and software for efficient electrical testing of integrated KOMPSAT-2 satellite in three general categories. (1) Simulators for ground testing (e.g. solar-simulation power, earth scenes, horizons and sun sensor). (2) Ground station type satellite data acquisition and processing test sets. (3) Overall control of satellite using hardline datum. In KOMPSAT (KOrea Multi-Purpose SATellite) program, KOMPSAT-2 EGSE was developed to support satellite integration and test activities. The KOMPSAT-2 EGSE was designed in parallel with satellite design. Consequently, the KOMPSAT-2 EGSE was based on the KOMPSAT-1 heritage since the spacecraft design followed the heritage. The KOMPSAT-2 baseline was elaborated by taking advantage of experience from KOMPSAT-1 program. The EGSE of KOMPSAT-2 design concept is generic modular design with preference in part selection with commercial off-the-shelf which were proven from KOMPSAT-1 programs, flexible/user friendly operational environment (graphical interface preferred), minimized new design and self test capability.

• Journal of the Korea Furniture Society
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• v.27 no.3
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• pp.203-210
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• 2016

According to the research on the gender ratio of furniture design courses at universities, female students account for 70 to 80 percent of the total enrollments. Likewise, other design courses reveal the similar trend. Even though female students want to build up their career in the furniture design or related fields, the figure is not so high. There is a trend that many female designers tend to take time off or quite their jobs after their marriage for that reasons such as pregnancy, childbirth, the upbringing of children and so on. The study also shows that women with higher education feel more difficult to resume their careers after being left from economic activity for a long period; this results in the lower figure of women involved in the specialized jobs than men. In particular, the furniture companies avoid hiring old female designers because they believe that younger candidates are more capable of learning the latest style; therefore, it has become harder for the job seeks to win the competition in the job market. The data released by Statistics Korea in 2015 shows that there was the higher increase in female employees than the figure of the male workers, compared to the previous year. As it can be seen, female workforce was emerged as the new growth power; Nevertheless, the working environment and conditions haven't meet the demands from women despite the gradual rise of female job seekers inspired by their wish to achieve self-realization, gender equality. To conclude, this is to suggest the plans for the foundation and management of small-scale carpentry studios so that women, who have a degree in furniture design studies and wish to resume their careers after their long breaks, start their own carpentry studios so as to reach self-realization and feel satisfied with their work while earning their livelihoods.