• Journal of Conservation Science
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• v.20
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• pp.43-54
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• 2007

The Muryangsa temple five-storied stone pagoda (Treasure No. 185) was geographically located in the area of the Baekje Kingdom. The architectural style of the Muryangsa temple five-storied stone pagoda is the pagoda at the early Goryeo Dynasty that was succeeded technique of the Baekje Kingdom and form of the Shilla Kingdom. Because this pagoda is located outside during old time that it received serious petrological and biological weathering in rock blocks and occurred the center subsidence in the upper capstone. This study executed ground stability interpretation in order to know what central subsidence in the upper capstone occurred for soft ground. The ground stability interpretation used seismic survey, electrical resistivity survey and GPR survey by non-destructive method. As the result, the ground appeared in the condition which is good. Specially, high resistance zone appeared from electric resistivity survey which come to seem with ground reinforcement harden. Consequently, central subsidence condition in the upper capstone is not by the instability of ground, and is judged with the thing by the structure instability in rock blocks over the upper capstone. This will be applied basic data with the long-term monitoring or preservation countermeasure of the pagoda.

• Corrosion Science and Technology
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• v.7 no.5
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• pp.259-264
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• 2008

A national consultative project entitled "corrosion cost survey in China and preventive strategies" was funded by the Chinese Academy of Engineering in 1998. Soon afterwards, an expert group was organized jointly by the Institute of Metal Research, CAS and Chinese Society of Corrosion and Protection. The report on corrosion cost survey in China was published in 2003. According to this report the overall annual corrosion cost in China estimated by the Uhlig Method and Hoar Method at 1997-2001 was found to be 200.7 billion Yuan RMB and 228.8 billion Yuan RMB respectively, which is equivalent to 2% of the gross national product of China. However the total cost of corrosion including the direct and indirect cost was estimated to be more than 500 billion Yuan RMB per year in China. Among them, corrosion cost of infrastructure ranked in first comparing with other sectors. Although corrosion costs in some sectors, such as electric power, petrochemical, oil pipeline and railway in China has reduced in the past years, significant losses are still being encountered in most sectors of industries and cost-effective methods have not always been implemented. Both successful and unsuccessful cases in corrosion control and corrosion management were collected. As the investment in capital construction continues increasing rapidly in China, the maintenance and life extension of the infrastructures will become a big issue. The preventive strategies have been suggested

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.3
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• pp.81-91
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• 2012

The world has been replacing fast fossil fuels vehicles with electric vehicles(EVs) to cope with climate change. The government set a goal which EVs will be substitute at least 10% of the domestic small vehicles with EVs until 2020, and will try to build electric charging infrastructures in apartments with the revision the law of 'the housing construction standards'. In apartments the EVs charging infrastructure and parking space is, essential to accomplish the goal. But the studies on EVs demand are few. In this study, we predicted that the demand for EVs using time-series analysis of statistical data, survey results for apartments residents in the metropolitan area. As a result, the ratio of the EVs appeared to be 6~21% for the total vehicles in a rental apartments for the years 2020, 21~39% in apartments for sales. For the EVs, the maximum power required for 1,000 households in rental apartment is predicted to be about 4200 kwh on a daily basis, while the maximum power in the apartment for sales is predicted to be 7800kwh.

• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.147-154
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• 2023

In this paper, we propose a barrier-free course route navigation service named "Theme Road" aimed at improving the mobility and convenience for elderly electric wheelchair users with walking disabilities. To achieve this goal, we conducted a user survey through shadowing and in-depth interviews to gather insights on the challenges experienced by elderly electric wheelchair users. We identified potential solutions for each inconvenience through co-creation workshops, resulting in a set of design considerations and app functionalities. Using persona development and service scenarios, we designed and implemented the "Theme Road" service as a dedicated navigation application for barrier-free course navigation. Unlike conventional route navigation and mapping services, our study stands out by offering a unique approach that combines recommended destinations and safe routes based on experiential analysis from elderly electric wheelchair users.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.2
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• pp.139-155
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• 2016

Present paper introduces the recent advances in space launch vehicle technologies. A brief survey is given for the space development programs in civil sector with their business model and key technologies. Advances in key technologies were reviewed in detail with more emphasis on the electric pump cycle engine for low cost high performance small launch vehicle, Electron, under development by Rocketlab Ltd., since their contributions would give good lessons for rocket scientists.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.657-665
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• 1991

Although orthogonal function is introduced in control theory in early 1970's, it is not perfect. Since the concept of integral operator by Chen and Hsiao in mid 1970's, orthogonal function (for example Walsh, Block-pulse, Haar, Laguerre, Legendre, Chebychev etc) has been widely applied In system's analysis and identification, model reduction, state estimation, optimal control, signal processing, image processing, EEG, and ECG etc. The reason why Walsh Functions introduces in control theory is that as integral of Walsh function is also developed in Walsh orthogonal function, if we transfer give system into integral equation and introduce Walsh function. We can know that system's characteristic by algebraical expression. This approach is based on least square error and that result is expressed as computer calculation and partly continuous constant value which is easy to apply. Such a Walsh function has been actively studied in USA, TAIWAN, INDO, CHINA, EUROPE etc and in domestic, author has studied it for 10 years since it was is introduced in 1982. This paper is consider the that author has studied for 10 years and Walsh function's efficiency.

• Economic and Environmental Geology
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• v.30 no.5
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• pp.451-458
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• 1997

The horizontal magnetic dipole as well as electrical dipole was adopted as a source to compute one-dimensional electromagnetic field behavior in controlled source magnetotellurics. he Cagniard impedances due to horizontal magnetic dipole source, especially phases, showed better frequency characteristics than those due to electric one. The magnetic dipole is inferior to the electric dipole in the point of relatively weak transmitting power at low frequency. But considering high resistivity charateristics of Korean geology, the magnetic dipole source is recommended for the survey up to depth of 500 m. A vector CSMT was introduced to get more reliable data in the area of two- or three-dimensional structures. A software and interpretation technique using polarization ellipses were developed. The technique was tested by synthetic data, which provided theoretical basis of the methodology. Although CSMT has inevitable limitation of investigation depth due to practically possible source-receiver separation, we proposed to use the technique developed in this paper where MT is not available, for example, in extremely noisy area or for shallow target.

• Archives of design research
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• v.19 no.3 s.65
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• pp.19-30
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• 2006

This study was carried out to present design guidelines for developing electric bikes which could be used for more users regardless of gender and age. Through a survey with 336 male and female respondents in Seoul aged between 10s and 70 years or older, the convenience of bicycle use and image preference by gender and age were investigated. To evaluate convenience of bicycle use, the 7 principles of universal design made by Universal Design Center were customized to fit for accessing bicycles. The following are results of statistical analysis on 301 valid data: (1) of the 7 principles, conventional bicycles were identified to be the most inconvenient in principle 6(low physical effort), followed by in principle 5(tolerance for error) and 7(size and space for approach and use). Women appeared to feel more inconvenience than men in all evaluation criteria while using bicycles. The relation between the convenience of use and users' age was not identified. (2) Preferred images by bicycle users turned out to be those of 'simple' and 'light.' By gender, male preferred more 'technical' and 'dynamic' images than female. By age, users in their 10s-20s preferred more 'individual' image than 70 years or older.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1916-1924
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• 2017

Fossil oil, as the main energy of transportation, is destined to be exhausted. The electrification of transportation is a sustainable solution to the energy crisis, since electric power could be acquired from the inexhaustible sun, wind and water. Among all the problems that hinder the development of Electric Vehicle (EV) industry, charging issue might be the most prominent one. In this paper, the service process of a charging station with Battery Energy Storage System (BESS) is analyzed by means of $Cram{\acute{e}}r$ - Lundberg model which has been intensively utilized in ruin theory. The service quality is proposed in two dimensions: the service efficiency and the service reliability. The arrival rate and State of Charge (SOC) upon arrival are derived from 2009 National Household Travel Survey (NHTS). The simulations are performed to show how the service quality is determined by the system parameters such as the number of servers, the service rate, the initial capacity, the charge rate and the maximum waiting time. At last, the economic analysis of the system is conducted and the best combination of the system parameters are given.

• Journal of Distribution Science
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• v.18 no.9
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• pp.31-43
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• 2020

Purpose: This study examined a comprehensive model for assessing the success probability of electric vehicle (EV) commercialization in the Korean market. The study identified three risks associated with successful commercialization which were technology, social, policy, environmental, and consumer risk. Research design, methodology: The assessment of the riskiness was represented by a Bayes belief network, where the probability of success at each stage is conditioned on the outcome of the preceding stage. Probability of success in each stage is either dependent on input (i.e., investment) or external factors (i.e., air quality). Initial input stages were defined as the levels of investment in product R&D, battery technology, production facilities and battery charging facilities. Results: Reasonable levels of investment were obtained by expert opinion from industry experts. Also, a survey was carried out with 78 experts consisting of automaker engineers, managers working at EV parts manufacturers, and automobile industry researchers in government think tanks to obtain the conditional probability distributions. Conclusion: The output of the model was the likelihood of success - expressed as the probability of market acceptance - that depended on the various input values. A model is a useful tool for understanding the EV industry as a whole and explaining the likely ramifications of different investment levels.