• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.12
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• pp.622-628
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• 2005

This paper is given a full detail of mathematical analyses of input current and output voltage for a novel active type power factor correction (PFC) converter. These are compared with harmonics components of input current for a conventional PFC converter. The proposed PFC converter is constructed in using a new loss-less snubber circuit to achieve a soft switching of control device. Also the proposed converter for discontinuous conduction mode (DCM) eliminates the complicated circuit control requirement and reduces the size of components. The input current waveform in the proposed converter is got to be a sinusoidal form of discontinuous pulse in proportion to magnitude of ac input voltage under the constant duty cycle switching. Therefore, input power factor is nearly unity and the control method is simple. Particularly, the stored energy of loss-less snubber capacitor is recovered with input side and increases input current from resonant operation. The result is that input power factor of the proposed converter is higher than that of conventional PFC converter. Some simulative results on computer and experimental results are included to confirm the validity of the analytical results.

• Journal of architectural history
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• v.3 no.2 s.6
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• pp.91-110
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• 1994

This paper is one of Korean towns in the period of Korean-Modern, which play an important role in shaping the present cities of Korea. In the concrete, this study deals with the urban form of the Japanese Concession at Womsan where is the second Open Port in Korea. By the way, both of the Open Port and the Concession were the town that not exist before the period of Korean-Modern, and the town that symbolize the historical characters of the period of Korean-Modern. On this study, it is intended to analyze the situations of establishment, the process of the urban form, and the meanings of Concession, from 1880 to 1910, the period when had been kept up the nature of the Concession mainly. The Japanese Concession at Wonsan was urged it's establishment by Japan Government that is conscious of the purpose of foreign trade and military importance. But, it was slow in progress of developing town because of the distance from the capital 'Han Yang', today we called it Seoul, and lack of the background towns. However, after both the wars of 1895 and 1904, Japanese residents were incresed and urban aspects were advanced. The urban form of Japanese Concession was devided two territories by the natural circumstances, so that was made a difference on the period of the development. And finally, it had double axis on the form of district. Furthermore, by increasing of residence, it was occured that new Japanese resident arwa was occupied and expanded illegally between the road which is toward the existing Korean village 'Womsan-Jin(元山津)'. This indeed is the illegal extension of the Japanese Concession at Wonsan. Conclusively, Concession fumed out the primary factor that Korean towns are altered with the heterogeneous ones in the period of Korean-Modern.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.6
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• pp.814-820
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• 2000

Statement of Problem. Commonly used classification systems do not inform for dentists the dimension of the available bone at a potential implant site although regarding a variety of morphologic and pathophysiologic aspects using schematic graphs. However, for the implantologist the availability of bone substance is most important independent whether it concerns the jaw basis or the alveolus. Purpose of Study. The present article refers to a new evaluation form, to analyze the available bone with regard to optional immediate loading site by site. According to a new systematic implant planning concept will be presented in two case reports. Results. The feasibility of the classification for planning and documentation of immediately loaded implants is presented in two case reports. Conclusion. The factor of bone support for immediate functional stability is important in dental implantology. The new systematic implant planning helps to systematically estimate the dimension (ASCIi classification) of the alveolus site by site to evaluate the possibility of immediate loading. The Gottingen classification thus aids to determine the degree of stability that can be expected for the planned solution.

• Korean Journal of Metals and Materials
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• v.46 no.4
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• pp.241-248
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• 2008

Gas turbine blades serviced for a period are usually repaired for reuse via "rejuvenation processes" including fluoride ion cleaning, brazing or welding, and recoating. Among these processes, the welding process is applied to rebuilt damaged parts of the blade in which welding materials being mostly Ni base superalloy are supplied in the form of powder or wire. When powder is used in the welding process, the uniform supply of powder is a very important factor for the uniformity of welding. According to our experience, the uniformity was very poor with the powder supply system only utilizing pressurized air flow. A new powder supply system was developed in which powder is supplied via air flow and simultaneously mechanically. The welding uniformity was much improved with this new system. In this study, the microstructure and mechanical properties of welded parts obtained from several kinds of powder using the new powder supply system were characterized.

• Journal of KIISE:Software and Applications
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• v.34 no.7
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• pp.667-680
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• 2007

The bio-data processing is used for a suitable purpose with bio-signals, which are obtained from human individuals. Recently, there is increasing demand that the bio-data has been widely applied to various applications. However, it is often that the number of data within each class is limited and the number of classes is large due to the property of problem domain. Therefore, the conventional pattern recognition systems and classification methods are suffering form low generalization performance because the system using the lack of data is influenced by noises of that. To solve this problem, we propose a modified additive factor model for bio-data generation, with two factors; the class factor which affects properties of each individuals and the environment factor such as noises which affects all classes. We then develop a classification system through defining a new similarity function using the proposed model. The proposed method maximizes to use an information of the class classification. So, we can expect to obtain good generalization performances with robust noises from small number of datas for bio-data. Experimental results show that proposed method outperforms significantly conventional method with real bio-data.

• Archives of design research
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• v.18 no.2 s.60
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• pp.211-218
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• 2005

As digital Information equipment is new arrival, new paradigm such as 'function exist but form don't' is needed in the field of design. Therefore, the activity of design is focused on the relationship of human and machine against visual form. For that reason, it is involved emotional factor in the relationship and studied on new field, the emotional interlace. The goal of this paper is to suggest the way of emotional interface on searching multimedia data. The main target of paper is effect sound and human's step and the main way of research is visualization after measuring and analyzing numerically similarity level among emotion-words. This paper suggests the theoretical bad(ground such as personal opinion, the character of auditory information and human's step and case studies on the emotion research. The experimental content about sound is fueled from my previous research and the main experimental content about human's step is made with regression-expression to substitute Quantification method 1 for value about stimulation. The realistic prototype to apply the research result will is suggested on the next research after studying the search environment.

• Journal of Sasang Constitutional Medicine
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• v.31 no.1
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• pp.65-78
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• 2019

Objectives This study aims to investigate how the Korean disease-related vocabulary is established or changed when it is translated into French or English. Through this, we examine changes in the meaning of diseases and the ecosystem of disease-related vocabulary in transition period of $19^{th}$ to $20^{th}$ century. Methods Korean disease-related vocabulary are extracted from a total of 148,000 Korean headwords included in our corpus of three bilingual dictionaries. Among them, the scope of analyisis is limited to group of vocabularies that include a high frequency words, disease(病) and symptom(症). Results The first type of change is the emergence of a neologism. In this case, coexistence of existing vocabulary and new words is observed. The second change is the appearance of loan words written in Hangul. The third is the case where the interpretation of meaning is changed while maintaining the word form. Finally, the fourth change is that the orthographic variants are displayed while maintaining the meaning of the existing vocabulary. Discussion Disease-related vocabulary increased greatly between 1897 and 1931. The increasing factor of vocabulary was the emergence of coined words, compound words and the influx of foreign words. The Korean language and the Western language made a new lexical form in order to introduce a new unknown concept to the Korean. We could also confirm that the way in which English word expanded its semantic field by modifying the way of representing the meaning of Korean Disease-related vocabulary.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.171-178
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• 2020

Amid public's growing interest on garden and more leisure time of modern life-style, there is an effort by the government to utilize forest as public garden. In order to utilize forests as pubic garden, a new concept of "Forest Garden" should be defined and introduced first. Furthermore, introducing a new concept requires academically analyzing values of a new concept before a new concept is widely used. Thus, we aimed to clarify the concept of forest garden by conducting Delphi technique research and factor-analysis of survey results. More specifically, delphi technique research was conducted to extract composition elements and explanation elements of forest garden. Factor analysis was conducted on the top 25 elements and 5 values were extracted as a result. They are form, scenery, ecology, history/cuture and usefulness which are essential values required of forest garden. Forest garden should have all of 5 values and be capable of function as both forest and garden which would also need continuous maintenance. We believe this study is the first one to establish definition of forest garden and more specific and realistic definitions need to be built through continuous research, 000 experiment and on-site evaluation. We also believe that this study will serve as foundation for further efforts in building forest garden in various space and in defining proper concept of forest garden.

• Korea Science and Art Forum
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• v.20
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• pp.227-241
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• 2015

As time is rapidly changing, the culture to represent an era is getting more subdivided and complex. Due to cultural diversity, the influence, cause, characteristics which could be understood in individual field centered by space in the past cannot be understood now only by the viewpoint of one field, and it has become difficult to predict and correspond to the change of the future. With the development of information and knowledge delivery system, various cultural contents to form a space are being created and lapsed, but there are a lot of parts which cannot be explained or understood by only one point of view. To inspect these situation, this study is aimed to draw the cultural and technical causes that became the influence with Suwon Hwaseong, a traditional space with historical superiority, analyze the key factors that became the main factor to form the space, and consider the importance of the related factors. Suwon Hwaseong is a new town formed by the order of King Jeongjo. Suwon Hwaseong at that time was a space with the will and effort of many people who dreamed a new era, and it has a meaning of varoius time ans space as historical facts and cultural values as well as the progress and development of scientific technology. The unstructured data technique which is applied as the method of analysis in this study can be said to be a new value judgement and viewpoint in interpreting the space. Therefore, this study is a new trial to provide a frame for multilaterally interpreting the various traditional space and culture of Korea from the past to the present.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.189-199
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• 1998

The system for optical tolerances of completion spectacles was made to sum of the accumulated error - the circumstances on composing prescription, the visual-distance, the tilting angle, the losing of a temple, the vertex distance, the axis of toric lens and the sloping of lens etc. It was given by the relation of allowed values size(T) and power(D), $T=T_0e^{-aD}$. Here, $T_0$ is the size of allowed values of plane-lens with power is 0 and ${\alpha}$ is the factor of allowed values. In case of being adopted to new form s tolerance corresponding to RAL 915, for the tolerance is large direction, the factor of allowed values ${\alpha}$ is $0.166(T_0=5.90)$ and for the tolerance is small direction, the factor of allowed values ${\alpha}$ is $0.166(T_0=2.95)$.