• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.7
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• pp.551-556
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• 2018

A lot of hardwares are allocated on the satellite to perform the attitude control. Sun sensor is very important hardware to acquire the initial attitude after separation from launcher and to maintain the safety attitude from the satellite anomaly operation. So the allocation of the sun sensor to acquire the field of view and the attitude control design using it, are critical work in the beginning of development. Number of Sun sensor for GEO-KOMPSAT2 is reduced with respect to COMS due to star tracker usage. The additional sun sensor using COMS heritage is considered. In this paper, it is described the analysis and the results on the method for the safety improvement which is to enlarge the field of view and to consider the harness connection of P/R-side of the sun sensor.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.1995-2003
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• 2014

Power semiconductor devices have been the major backbone for high-power electronic devices. One of important parameters in view of power semiconductor devices often characterize with a high breakdown voltage. Therefore, many efforts have been made, since the development of the Insulated Gate Bipolar Transistor (IGBT), toward having higher level of breakdown voltage, whereby the typical design thereof is focused on the structure using the field ring. In this study, in an attempt to make up more optimized field-ring structure, the characteristics of the field ring were investigated with the use of theoretical arithmetic model and methodologically the design of experiments (DOE). In addition, the IGBT having the field-ring structure was designed via simulation based on the finding from the above, the result of which was also analyzed. Lastly, the current study described the trench field-ring structure taking advantages of trench-etching process having the improved field-ring structure, not as simple as the conventional one. As a result of the simulation, it was found that the improved trench field-ring structure leads to more desirable voltage divider than relying on the conventional field-ring structure.

• Journal of Korean Philosophical Society
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• v.105
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• pp.269-290
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• 2008

The purpose of this paper is to explore the possibility of backwards causation. For study, this paper was divided into four views as follows: The first view was sometimes suggested by the people such as M. Dummett who distinguished observers from behaviors. According to observers' view, backwards causation is impossible, whereas behaviors' view possible. However, in a real or genuine sense, it is incorrect for us to argue for impossibility of backwards causation from the observer aspect. The second view was supported by J. H. Schmidt. He analyzed the possibility of backwards causation in terms of macro and micro level analysis about the causal events. According to micro level analysis, backwards causation is possible, but macro level analysis impossible. Usually the latter makes the former something miraculous. Under the macro level analysis, backwards causation, at first, seems to be miraculous phenomena which belongs to the micro level analysis. The third view had to do with physical equation, and the fourth view physical phenomena, respectively. John Earman argued for the backwards causation by the transformation from Lorentz­-Dirac equation to a second-order integro-differential one in the field of electrodynamic acceleration. His argument was criticized because of his misunderstanding about the relationship between two equations. On the other hand, Phil Dowe defended a version of Reichenbach's own theory about the direction of causation founded on the fork asymmetrical causal relation. However his view was different from Reichenbach's because the former defended the backwards causation model of Bell phenomena in quantum mechanics. On the contrary, Reichenbach put stressed on the priority of cause in the causal process. Subjectivism has recently been defended by H. Price, under the label of perspectivism. According to him, in a certain sense causal asymmetry is not in the world, but is rather a product of our own asymmetric perspective on the world. He also suggested causal net, the symmetry of microphysics, and so on. As mentioned above, there are many kind of suggestions of backwards causation. However none of them replaced objectively the main streams of the direction of causal process. The main stream has been usually defended by pragmatical ground. That is, effects do not precede their causes although causes cannot be without their effects.

• Geophysics and Geophysical Exploration
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• v.19 no.4
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• pp.200-211
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• 2016

To support cross potential array and direct potential array, the array for leakage detection of all kinds of water facilities is proposed and it is named as the D-Lux array. The D-Lux array data are arranged to a coloured matrix and it is called the D-Lux view. Low potential difference of anomalous zone shown in D-Lux view implies the indication of leakage zone. Furthermore, for an intuitive interpretation of D-Lux array, equipotential distribution map is made by using D-Lux and direct potential array data. Equipotential distribution map makes us possible to predict import point, export point and the path of water leakage that we could have not anticipated in D-Lux view and the graphs. The water tank experiment and numerical analysis were carried out as preparatory experiment and the field explorations were conducted at a concrete weir and a fill dam. As a result, effective and specific detection of leakage path was possible for the concrete weir and the fill dam.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.3
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• pp.31-38
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• 2020

The purpose of this study is to compare between professionalism in medical field(doctor) and architectural design field(architect) in Korea through synchronic and diachronic analysis, with basic requirement of expertise and systemicity, attitude requirement of the publicness, and structural requirement of exclusiveness and autonomy. The medical professionalism adapted by Korean government in the early period of modernization evolved from Western's professional expertise is highly divided as economy grew and society changed. In comparison, architecture was divided into architecture, urbanism, landscape, and interior architecture. Additionally, architectural field was subdivided with architectural design, engineering, construction, structure, and facilities, but architectural design focused on generalized education and practice system. From the systematical point of view, architectural design field has changed profoundly from architectural engineering as 5 year undergraduate educational system was introduced with Korean architectural accreditation. The publicness is approved through health service in medical field and safety and the public domain in architectural design field, but in reality the professionals are viewed as economic interest groups. Hence, the professionalism in both fields is required to reinforce ideology and ethics, and to practice concrete measures for publicness. Compared with the unified organization of medical field, architectural design professionalism faces various difficulties in unifying the organization, such as internal competition caused by tightened architect's requirements, along with external problems from architectural design permission demands of construction companies. In medical and architectural design professionalism, with the appearance of consumerism and stricter governmental regulations, the autonomy is weakened. From the result of comparative analysis, Korean medical field became extremely subdivided and specialized in each department, therefore integration of each disease and establishment of centers are proposed as solutions. By contrast, the reinforcement of expertise in architectural design professionalism might be necessary to strengthen autonomy caused by governmental restriction, and to form architectural culture and secure public architecture.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.7 no.1
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• pp.247-262
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• 1994

This study is concerned with analysis of all the reviews published by the reviewing periodicals, The Book Review Culture and The Korean Publishing Journal, from 1991 to 1993. The result of analysis for 736 reviews are followed： 1) The percentage of reviews in the field of philosophy & religion, literature ＆ language, science ＆ technology is lower than the percent-age of books published. But in the field of history and social science the reviewing is proportionately higher than the publishing. 2) Book reviews are prepared by professors, literary reviewers, researchers, and experts in the particular subject field except librarian. 3) Basic elements of reviewing are the career and view point of author, trends of suject field, content, value, omissions, limitations, and format of book, reader's level, etc. Ideal method of book criticism may be summarized as follows： 1) The criterion of book selection are the book's value, the social . demand, and the proportion of titles published. 2) For the unbiased criticism, it should be written by the experienced librarian rather than the experts of particular subject field. 3) Book criticism need to provide not only guide to new books but also interpretation and evaluation about each book for its reader.

• East Asian mathematical journal
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• v.29 no.3
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• pp.293-302
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• 2013

We research properties of ternary numbers and hyperholomorphic functions with values in $\mathbb{C}$(2). We represent reduced quaternion numbers and obtain some propertries in dual reduced quaternion systems in view of Clifford analysis. Moreover, we obtain Cauchy theorems with respect to dual reduced quaternions.

• Journal of Korea Technology Innovation Society
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• v.6 no.2
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• pp.175-190
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• 2003

This paper deals with the methods for selecting the key research areas, which fit for the large, multi-disciplinary, and long-term programs by making use of Technology Cluster Analysis. This method is applied to mano-technology field at the level of national R&D program. 56 nano-technologies are analyzed and grouped into three main clusters based on the survey data from 180 experts. Three main clusters are \circled1 naro-materials related cluster, \circled2 naro-device related cluster, and \circled3 naro-bio related cluster. These three clusters are coincided with the focused areas of nano-technology in Korea. Each cluster is analyzed in view of its competence position.

• 한국가시화정보학회:학술대회논문집
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• 2002.11a
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• pp.51-52
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• 2002

Electro-osmotic flow in a PDMS microchannel of $66{\mu}m\;\times\;200{\mu}m\;\times\;3cm$ has been investigated using a micro PIV system. The field of view was $1056{\mu}m\;\times\;200{\mu}m$ and instantaneous velocity fields were obtained using two-frame cross-correlation method with $64\;\times\;64\;pixels^2$ interrogation window. In this study, we focused on the effect of applied electric field on the variation of internal flow with varying the electric field and seeding particles. The electro-osmotic flow shows a flat velocity profile and the mean velocity is proportional to the applied electric field.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.63-75
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• 2006

The exploration of the spatial structure of a particular urban area, or the analysis of the tendencies of spatial consumption among urbanites, can be a literary-geographical attitude, shifting literary interests toward geography. It may also constitute a field of cultural geography that reads texts as cultural symbols. Based on this kind of attitude, the paper reads the literature of Park Wan So, particularly the popular novels that involve urban and residential spaces of Seoul, as a cultural text that carries a kind of symbolism. It proceeds with the idea that most popular novels reflect the mass phenomena of its times, and that representing real cultural experiences through text, it becomes a means of generalizing the identity shared by the anonymous masses and the characteristics of particular places. Hence the individuality of Park Wan So, who moved to Seoul during the Japanese colonial period and hence forth lived as a middle-class citizen, is inseparable from her literary work. With this attitude and methodology, the paper argues that in the urban space of metropolitan Seoul, the modern ambivalent gaze of the colonial period shifted toward increasingly new value systems, and was replaced by a dichotomous view, and furthermore, that the contents of this dichotomous view has experienced a multivalent transformation through the accumulation of time and the expansion of space.