• New & Renewable Energy
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• v.7 no.2
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• pp.36-42
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• 2011

The wind speed at the altitude around 300 m is much higher and less variable than at the altitude around 80 m which is the same height of the MW class tower turbine's hub height. The wind power density is increased 0.37 W/$m^2$ per meter at the altitude around 6 to 7 km and 0.25 W/$m^2$ per meter at the altitude around 80 to 500 m. There are two types of power generation systems using lifting bodies. The one is that The generator is installed in the ground station and stretched into the lifting body through the tether. The other is that the generator is installed in the lifting body and stretched into the ground station through the tether. Many kinds of lifting bodies are also researched in the world, called kites, wings, single or twin aerostat, and so on. This article introduced the technical development status and the market prospects of the high altitude wind power generation system all over the world in detail.

• Journal of the Korean Society of Systems Engineering
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• v.11 no.1
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• pp.25-31
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• 2015

Under the relevant regulations, it is required to develop a system architecture for the research and development of the information and communication infra system ; however, the national defense architecture development guides and MND-AF, which provide the instructions on the development and utilization of a system architecture, are still limited to the ITA level and merely providing the guidelines for developing the information system centric architecture. Thus, it is evident that we need a suitable architecture development methodology that corresponds to the growing needs for the communication infra system architecture, as well as the general weapon system architecture. Improving a meta-model is the core of improving a architecture framework. It determines a contents of a architecture and it influences a efficiency and a effectiveness of a architecture. The meta-model of the architecture framework must reflect concerns of various stakeholders and provide a traceability among them. Also, it should be easy to develop and use the architecture by securing the feasibility of the logical relationships and eliminating the duplication of the data inside the architecture. It is implemented through the development of the data-centric architecture and achieved through the "Fit-for-purpose" concept.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.541-550
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• 2018

The works of preparing for missile flight test are becoming more complicated. To reduce the amount of waste time along with the complexity of the task, systematic analysis of waste factors should be performed before performing process improvement. The waste factors for missile flight test are first defined using lean-based waste factors. The improvement priorities for the defined waste factors are surveyed. For reliable analysis, AHP is used in questionnaire analysis instead of the existing method with large error. Then weighting and priority for waste factors for level 1 and Level 2 are suggested. Through AHP, we could derive reliable improvement priorities for waste factors. It is analyzed that the biggest cause of waste factors is waiting time and identified as the first item to be considered when establishing improvement plan. In addition, suggestions for improvement measures of waste factors are presented through brainstorming method. Reliable results will be an important factor in process redesign for missile flight test works.

• Journal of the Korean Solar Energy Society
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• v.29 no.5
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• pp.14-19
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• 2009

The 50 kWp grid connected photovoltaic system which was installed at KEPRI site in 1999 has been operated more than 10 years. In order to acquire long term operation characteristics of medium size photovoltaic system, the operation test data related on power generation electricity and capacity factor of 50 kWp system, which have been collected since 1999, were analysed. From the analysing results, 57.7 MWh in annual power generation electricity of 50 kWp photovoltaic system in 1999 has been decreased 49.1 MWh in 2005 and reached 41.9 MWh in 2008. In addition to, the capacity factor of 50 kWp photovoltaic system also showed 13.2 % in 1999, 11.2% in 2005 and finally reached 9.6% in 2008. The operation test data showed a trend of decreasing of generation electricity and capacity factor during the 10 years operation time and we guessed that was caused by solar cell performance degradation and decreasing of PCS system efficiency.

• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.345-353
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• 2010

The purpose of this study was to compare and biomechanical evaluate the effects of three varying functional insoles on the kinematics of the lower extremities and foot pressure distribution during gait. For this 12 subjects participated in this study and each worn the 3 functional insoles during gait which kinematics, kinetics, electromyography and foot pressures were recorded. The function on the first insole was to absorb shock and increase the dynamic stability, the second was a gel type to absorb shock, and the third was to massage the center regions of the foot sole. the results were as follows; the first insole reduced the joints range of motion and reduced muscular fatigue, the second insole reduce the maximum, total and average foot pressures. Finally, the third insole produced larger values for the contact times and contact area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3130-3136
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• 2009

This paper deals with the optimal on-line real time voltage regulation methods in power distribution systems interconnected with the Distributed Generation(DG) systems. In order to deliver suitable voltage to as many customers as possible, the optimal sending voltage should be decided by the effective voltage regulation method by using artificial neural networks to consider the rapid load variation and random operation characteristics of DG systems. The results from a case study show that the proposed method can be a practical tool for the voltage regulation in distribution systems including many DG systems.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.8-14
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• 2011

Recently, a number of large-scale photovoltaic(PV) power generation system has been installed all over the world. Thus, in order to improve the system efficiency, the optimal design of the large-scale PV systems has become an important issue. DC cable loss of PV array is one of the design factors related to the system efficiency. This paper introduces the array design method of a 500kW Photovoltaic power plant. Three types of the PV array are suggested. Also, string cables, sub-array cables and array cables are designed within 1% of voltage drop in the line, and the DC cable losses are analyzed. The results of this paper show that the DC cable loss of large-scale PV array can be reduced by adopting a proper sub-array design method.

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.175-192
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• 2006

The purpose of this study was to analyze the current status and suggest tasks of future directions for development of the Korean Society of Sport Biomechanics(KSSB). KSSB was established in the 22th of Oct.,1988. It is one of the great National Society recognized by the Korean Research Foundation, and consists of almost 350 members over national Sport Biomechanists. Two roles-functions of KSSB are as follows; one is an Independent Society by KSSB, the other is a sub-Society under Korean Alliance for Health, Physical Education, Recreation and Dance(KAHPERD) run by 15 sub-Societies. The 2 great strategies toward all over the world of KSSB were Localization and Globalization. The grand four projects of KSSB in $2005{\sim}2006yrs$ are as followers: 1) The rationalization of organization-operating and decentralization, 2) The international levels of society, 3) The internationalizaton of quality of Korean Journal of Sport Biomechanics, and 4) The presentation award by quarterly and double-movements of members of KSSB. The tasks of future direction for development of KSSB are as followers : The localization and globalization of KSSB( see above as figure 4, table 12, 13, 14).

• The korean journal of orthodontics
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• v.15 no.2
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• pp.175-195
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• 1985

Vertical and horizontal growth occur in the craniofacial complex which ensues continuous changes in facial morphology, until the end of active growth period. Longitudinal study for individual is essential, in the research on growth and development, however, the difficulties in obtaining long term subjects in Korea, the research has been limited. The author analyzed the cephalometric roentgenogrems of 43 boys and 47 girls taken from the ages 6 to 10. The subjects were divided into 3 groups according to SN-MP angle and 2 groups according to gonial angle. In this longitudinal study, 21 variables were measure 4. The obtained results were as follows: 1. SN-MP angle and genial angle had no significant changes in each group with age. 2. With age, facial convexity of hard tissue decreased in all groups, facial angle of hard tissue increased in low SN-MP angle group, but facial convexity of soft tissue had no significant changes in all groups with age. 3. In comparison of high SN-MP angle group and low SN-MP angle group, the former had greater facial convexity and smaller facial angle than the latter. 4. SN-MP angle and the ratio of posterior dental height to anterior dental height had reverse correlation in all groups. 5. High genial angle group revealed larger SN-MP angle, anterior dental height facial convexity, but smaller mandibular length, and the ratio of posterior dental height to anterior dental height compared with low genial angle group.

• KIPS Transactions on Computer and Communication Systems
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• v.4 no.11
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• pp.361-368
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• 2015

In AAGFCS the effective range is regarded as a range for the bullet's speed exceeding the speed of sound to damage the stationary target. Hence the real engagement range might be extended over the effective range for the approaching target since bullet's relative speed to the target increases depending on the approaching speed. However previous TOF equations have good computation accuracy within the effective range only, and they can not be used above that range due to their bad accuracy. We propose an accurate TOF computation method which can be used both within and above the effective range in real time. Some simulation results are shown to demonstrate usefulness of our algorithm for the 30mm projectile.