• Journal of Astronomy and Space Sciences
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• v.1 no.1
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• pp.41-53
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• 1984

Photoelectric observations of the close eclipsing binary system CW Cep, which is well known of its apsidal motion, were made on 20 nights during August and November in 1983 using two 61cm reflectors at the Sobaeksan Observing Station of Korean National Astronomical Observatory and I1san Observing Station of Yonsei University Observatory. Standardized new light curves in UBV system are presented with a total of 1,422 individual observations. For the corrections of regional and instrumental differences, same standard stars were observed at the two observatories. Four new times of minimum light were determined with the method of Kwee and van Woerden(1956). With all of the collected times of minima, apsidal motion of this system was checked, but the O-C values calculated by the light elements of Nha(1975) and Soderhjelm (1976) did not coincide well with new times of minima. New light elements which satisfy most times of minima better, and are deduced the apsidal period derived by the new light elements turns out to be 43 years, somewhat longer than those of values previously known.

• Advances in concrete construction
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• v.4 no.3
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• pp.173-194
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• 2016

This paper consists in a study of a new contructive sequence of road viaducts with Movable Scaffolding System (MSS) using numerical tools based on finite element method (FEM). Traditional and new sequences are being used in Spain to build viaducts with MSS. The new sequence permits an easier construction of one span per week but implies some other issues related to the need of two prestressing stages per span. In order to improve the efficiency of the new sequence by reducing the number of prestressing stages per span, two solutions are suggested in this study. Results show that the best solution is to introduce the 100% of the prestressing force at the self-supporting core in order to improve the road viaduct construction with movable scaffolding system by reducing execution time without increasing economic costs.

• Journal of the Korean Solar Energy Society
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• v.26 no.2
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• pp.43-51
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• 2006

New renewable energy information becomes one of the greatest issues all over the world because of serious environment problems and limited fossil resources. The new renewable energy source information system is treated seriously for efficient management and distribution as dealing with these energy problems. However, it is difficult to manage and utilize new renewable energy information because gathering and surveying information is progressed individually in each research field. Therefore this paper will establish ISP(Information Strategy Planning) and propose the basic management system based-on GIS to analyze new renewable energy such as solar energy, wind power, small hydro, biomass, geothermal etc. and build the integration management system. The proposed integration management system can provide spatial analysis using thematic map, data search, data import/export and interpolation about users' queries.

• Journal of Service Research and Studies
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• v.12 no.3
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• pp.115-133
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• 2022

This study was conducted to design a new human model and education system for the sustainable life of mankind. Human society is facing a crisis. This study presents a comprehensive plan as the final version of the servicism study. Since the problems of human society are all human problems, research was conducted focusing on the new human and education system. Modern society is markedly different from the existing society in terms of time, space, and humanity, and the leading role of individuals is increased due to the increase in literacy, which can lead to breakdown and ground breaking in an instant. As the value of growth and freedom is increasing, technological innovation is accelerating, and industries and enterprises are growing significantly, so new technologies and industries may put human society at great risk. This study comprehensively diagnosed these problems in the current human society. The problems related to human and education were presented in depth while analyzing and synthesizing the problems presented in the existing servicism studies. The necessary and sufficient conditions for a new system to solve the problems raised were derived. And a system that satisfies these conditions was derived and presented. The new system was named servicism human and education system as a system based on the service philosophy. The structure, operation model, and implementation plan of the new system were presented. The basic structure is a human view that recognizes both reason and irrationality, an education system in which intelligence education and virtue education are balanced, and an education system in which human effort and the values of unwieldy nature are respected. A new education system needs to be put into operation along with the improvement of modern ideology and the compensation system for efforts. Since this study presented a macroscopic direction, further studies are needed to further refine this study.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.859-864
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• 2015

This paper analyzes the impact of Plug-in Electric vehicles(PEVs) on power demand and voltage change when PEVs are connected to the domestic distribution system. Specifically, it assesses PEVs charging load by charging method in accordance with PEVs penetration scenarios, its percentage of total load, and voltage range under load conditions. Concretely, we develop EMTDC modelling to perform a voltage distribution analysis when the PEVs charging system by their charging scenario was connected to the distribution system under the load condition. Furthermore we present evaluation algorithm to determine whether it is possible to adjust it such that it is in the allowed range by applying ULTC when the voltage change rate by PEVs charging scenario exceed its allowed range. Also, detailed analysis of the impact of PEVs on power distribution system was carried out by calculating existing electric power load and additional PEVs charge load by each scenario on new-town in Korea to estimate total load increases, and also by interpreting the subsequent voltage range for system circuits and demonstrating conditions for countermeasures. It was concluded that total loads including PEVs charging load on new-town distribution system in Korea by PEVs penetration scenario increase significantly, and the voltage range when considering ULTC, is allowable in terms of voltage tolerance range up to a PEVs penetration of 20% by scenario. Finally, we propose the charging capacity of PEVs that can delay the reinforcement of power distribution system while satisfying the permitted voltage change rate conditions when PEVs charging load is connected to the power distribution system by their charging penetration scenario.

• Journal of information and communication convergence engineering
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• v.5 no.4
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• pp.358-361
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• 2007

We report on a new type dc-dc converter design that combines the advantage of dc ripple noise elimination and high efficiency. As potential low cost solar cells, DSC module and the panel's system efficiency and stability are still critical problems to the way of marketing. In this study, a new three-step dc-dc converter scheme with the phase-shift-carrier technology is proposed to apply for solar power system. We have achieved power conversion efficiency around 94.88%.

• Journal of Korean Library and Information Science Society
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• v.23
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• pp.439-469
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• 1995

The purpose of this study is to develop a new domestic (national) law classification scheme with universality. An underlying reason for the development of this scheme reset upon the fact that Civil law system, Common law system, Socialistic law system have had difficulties each other and that current classification scheme covering three law systems have not been still in existence. From the comparative discussion of classification schemes that are the representative of each law system, a new national law classification scheme with universality was designed. If law classification scheme have been completeness, this new scheme must be combined with jurisprudence and international law classification scheme which was developed already.

• IE interfaces
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• v.19 no.3
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• pp.181-189
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• 2006

This study introduces an overall framework for RFID applications in product lifecycle management(PLM). PLM is a new strategic approach to manage product related information efficiently over the whole product lifecycle. Recently, with emerging technologies such as radio frequency identification(RFID), global positioning system(GPS), and wireless communication, PLM provides a new environment that enables us to gather and analyze product lifecycle information, and make decisions on several issues without spatial and temporal constrains. However, a PLM system just provides us with new opportunities to gain the PLM system, first and foremost, it is necessary to look into its overall framework in the viewpoint of hardware, software, and business model. For this purpose, in this study, first, we introduce the technical framework of the new PLM environment with the concept of extended RFID system, called product embedded information device(PEID). Then, for each lifecycle phase such as beginning of life(BOL), middle of life(MOL), and end of life(EOL), we explore several research problems that become highlighted under the new PLM environment.

• Journal of Biosystems Engineering
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• v.41 no.2
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• pp.67-74
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• 2016

Purpose: Many tractors have adopted the horizontal control system designed to maintain the three-point mounted implements in horizontal position when they are tilted sideways. The control system rotates the implement in the opposite direction to the inclination of rear axle of the tractor. However, the current control system was found to have poor performance in accuracy and response. A new control system was therefore developed to improve the performance. Methods: The new control system was designed to get the response of the implement to be started earlier by using the tilt information from the front axle of the tractor. By this approach, the rotation of the implement can be adjusted as required to make it horizontal at the expected time, even though the response is slow. The optimal values of the control parameters for the new system were determined by computer simulation and validated by a performance test conducted with an obstacle of 120 mm height on a flat concrete surface. The performance of the control system was evaluated by the root mean square error (RMSE) of the rotation angle of the implement with respect to the actual inclination of the rear axle. Results: The new control system reduced the RMSE of the current control system by 44.6% indicating a high performance improvement. The inclination of the front axle was easily obtained from a sensor mounted on the front axle of the tractor and used as input to the new control system. Conclusions: The method of getting the response of the implement to be started earlier by utilizing the inclination information of the front axle can be applied to improve the performance of the current control system at least cost.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.196-202
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• 2009

Study from Yogyakarta earthquake reconstruction program, cast-in-place wall using fix-size formwork system (Old-CIP) has offered a good alternative for house construction. A simulation has also confirmed that this system using mortar as the main material can provide cheapest cost and lowest total man power compared to conventional wall construction technique: brick or mortar-block wall. This paper presents the new wall construction technique: full size cast-in-place wall (New-CIP). The detail of how this new technique implemented is described. In addition, considering that material and labor cost in one area is different to others, cost analysis for different resources prices and wages of three cities are taken into a simulation. The analysis is aimed to distinguish the implementation feasibility of New-CIP system compared to the four common wall systems. Finally, its implementation resistance is also discussed.