• Proceedings of the KSR Conference
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• 2008.06a
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• pp.841-848
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• 2008

This paper examined dynamic characteristics of high speed trains using a time varying frequency transform. Fourier transform based methods are frequently used for the calculation of the dynamic characteristics of trains in the frequency domain, but they cannot represent the time-varying characteristics. Therefore it is necessary to examine their characteristics using a time-varying frequency transform. For the examination, the non-stationary vibration of wheelset, bogie, and carbody are measured using accelerometers and stored in a data aquisition system. They are processed with localization of the data by modulating with a window function, and Fourier transform is taken to each localized data, called the short-time Fourier transform. From the processed results, time varying auto-spectral density, cross-spectral density, frequency response, and coherence functions have been calculated. From the analysis, it is confirmed that the time varying frequency transform is a useful method for analyzing the dynamic characteristics of high speed trains.

• Journal of the Korea Society of Computer and Information
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• v.21 no.8
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• pp.1-12
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• 2016

In this paper, we propose a very efficient reversible data hiding algorithm using spatial locality and the surface characteristics of image. Spacial locality and a variety of surface characteristics are present in natural images. So, it is possible to precisely predict the pixel value using the locality and surface characteristics of image. Therefore, the frequency is increased significantly at the peak point of the difference histogram using the precisely predicted pixel values. Thus, it is possible to increase the amount of data to be embedded in image using the spatial locality and surface characteristics of image. By using the proposed reversible data hiding algorithm, visually high quality stego-image can be generated, the embedded data and the original cover image can be extracted without distortion from the stego-image, and the embedding data are much greater than that of the previous algorithm. The experimental results show the superiority of the proposed algorithm.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.5
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• pp.272-277
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• 2006

The present study is devoted to investigate numerically the optical characteristics of multi-layer thin film structures such as $Si/SiO_2\;and\;Ge/Si/SiO_2$ by using the characteristics transmission matrix method. The reflectivity and the absorptivity rate for thin film structures are estimated for different incident angles of rays and various film thicknesses. In addition, the influence of wavelength on optical characteristics related to complex refractive index is examined. It is found that such wave-like characteristics are observed in predicting reflectivities and depends mainly on film thickness. Moreover, the present study predicts the film thickness for ignoring wave interference effects, and it also discusses the fundamental physics behind optical and energy absorption characteristics appearing in multi-layer thin film structures.

• Journal of the Korean Society of Costume
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• v.50 no.7
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• pp.75-96
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• 2000

Modern clothing is approached in the level of art, and it becomes the means of expressing individuality in modern society uniformed by the development of information society. In this modern society, modern men need the recovery of humanity and expectations of handcrafted skills for the succession of tradition culture. Prior to expressing individuality, we should examine our traditional culture and combine it with western culture. Quit started to be used for practical purpose such as life items, but it is expanded to the fields of art. Used in dress and its ornaments design, quilt is often applied to the addition of aesthetic factors or cubic material feelings by transforming its warming effect. Hereby, this study has a purpose to create high value added modern dross and its ornaments design by expressing the modern clothing is approached in the level of art, and it becomes the means of expressing individuality roe-dimensional characteristics of quilt, and applying the color combination and the surface of butterfly wings to dress and its ornaments design. The following are the results of this study. 1. The concept of quilt started for practical purposes, but it is expanded to decoration in modern times, and it is confirmed that quilt can be variously applied to handcrafted modern design. 2. Quilt removes the plane character of textile and it riches the three-dimensional material of dress and its ornaments. Applying these characteristics, the expression of transparent wings were possible with 3 transparent layers of textile. 3. The spledid color of butterfly wings are expressed by coloring oganza and felt, and the various colors of felt showed rich color gradation. 4. The form and pattern of butterfly wings are applied as modeling form and line, and the transformation. repetition and expansion of unit forms determined the form of quilting lines. By designing the characteristics of back wings for the composition line of clothing, the form characteristics of a motif could be emphasized. 5. By using felt, oganza, Damdam yarn and ostritch feathers in expressing butterfly wings, the warm material of Linbun is felt, and the tip hair of wings are expressed by croche techniques using Damdam yarn.

• Journal of Digital Convergence
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• v.9 no.6
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• pp.173-186
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• 2011

In this study, the influence of the CEOs' characteristics on the technology innovation performances of IT venture companies was analyzed. The relation between business performance and the characteristics of CEOs has been dealt with in earlier studies, but most paid attention to financial perspective, and few of these focused on the influence of managers on technology innovation. On the other hand, most of the studies related to the role of managers in technology innovation mainly focused on R&D investment and research infrastructure but did not delve on the characteristics of them in an in-depth way. In this study, the characteristics of CEOs and their technology innovation performances were empirically analyzed based on the results of a recently conducted survey on the IT venture companies. In the analytical aspect, a negative binominal model was applied to solve the over-dispersion problem that often appears in the count variable analysis. As a result, it was found that major, work type, and work experience, among managers' characteristics, have significant influences on managers' technology innovation performances, along with the company's innovation capacity, technological competitiveness, market competition, and support from the government.

• Journal of the Korean housing association
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• v.15 no.1
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• pp.195-204
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• 2004

This study was carried out to understand the architectural characteristics of farmhouse among the commons house. The subject of study are selected the seventeen farmhouse built 50-60 years ago at Hyunri in Munkyung. It was analyzed and classified the architectural characteristics of plan and arrangement at a farmhouse. In conclusing, their farmhouses are appeared the different characteristics in comparison with other area. With the arrangement of building and composition of plan, it was discovered that it connotes an idea of the confucian ideas from separation of the inside and outside space; men and women. Also, it was found that it has become to the rational separation of spaces from location of entrance, division of the outside space(Madang) and arranged space of inside at farmhouse.

• Architectural research
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• v.23 no.3
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• pp.49-54
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• 2021

In contemporary modern architecture, it can be said that Western modern architecture, which has advanced in technology and ideology, is leading the world architecture today. However, because it is pointed out that modern architecture, mainly represented by Western architecture nowadays, is based on the crystal of Western civilization's consumption and capitalist culture, and because it seems not absolute for the eternal sustainable development of the Earth and happiness of Humankind, it is assumed that the new conceptions of Architecture should include the cultural, ecological and environmental characteristics of the region. So because it is thought that the latent characteristics of East Asian architecture including China, Japan and Korea has the advantage of reducing the deficiency of Western modern architecture and contributing to human civilization, this study was written to find a new direction of architecture by finding the differences of architectural characteristics(intrinsic and extrinsic) in the interior of the architectural result through comparison between the Eastern and Western architecture.

• The Research Journal of the Costume Culture
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• v.28 no.2
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• pp.181-198
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• 2020

Using the developed wedding planner selection criteria scale, this study examined whether wedding planner selection criteria differ according to consumer characteristics such as demographic characteristics and wedding preparation behaviors. The main survey for this study was conducted via the Internet with 295 consumers aged 20-30 living in the Seoul metropolitan area. The data collected from the survey processed and analyzed using the statistical programs SPSS 21.0 t-test. Analyzing how wedding planner selection criteria differ according to consumers' demographic characteristics and wedding preparation behaviors, results shown for the wedding planner selection criteria were all four points on average except for individual characteristics and important sub-factors regardless of the consumers' characteristics, and various results were derived depending on the consumers' characteristics. This study has various practical implications in that it verified the difference in wedding planner selection criteria according to consumer characteristics and determined how much money consumers were willing to play for wedding planners. It is recommended that future studies take various approaches to investigate how wedding planner users are satisfied with or place importance on wedding planner services and conduct empirical using the selection criteria developed in this study to compare influential variables that affect behavior intention and willingness to pay according to consumer type.

• Fashion & Textile Research Journal
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• v.11 no.2
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• pp.301-307
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• 2009

The purpose of this study is to investigate the problem and complaint of current flight suit derived with the questionnaires. The survey was carried out to the 137 aviators in Army Aviation School from April to May, 2007. The questionnaires were composed of personal characteristics, usage characteristics, wearing characteristics and free comments. Regard to the questionnaires of usage characteristics, they wore the flight suit over 6 hours a day and over 5 days a week. For wearing convenience item in usage characteristics it was revealed that fitness, ease and the location of pocket were not proper, Also, it showed that the material characteristics(e.g. insulation, absorption, and sensation) for flight suit was not proper. Regard to the questionnaire of wearing characteristics, the most inconvenient part is crotch as the answer on the question of "unfitting part in size" and "inconvenient part when wearing". Free comments for the improvement requests are various size, material, stitch strengthening, pattern modifying, and accessories.

• Land and Housing Review
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• v.11 no.2
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• pp.25-32
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• 2020

This study classified and analyzed characteristics of residents in public rental housing based on data from the 2018 Housing Survey. First, in order to classify the type of public rental housing resident, the criteria were derived through factor analysis based on the satisfaction evaluation index. Next, based on the factor value, the group was classified by type through cluster analysis, and the satisfaction, characteristics of residential households, and characteristics of rental housing types were analyzed for each cluster. As a result of factor analysis, evaluation of housing facilities, accessibility, and residential comfort was selected as the cluster classification criteria, and a total of four clusters were derived through cluster analysis. As a result of analyzing the characteristics of each cluster, it was found that there was a statistically significant difference in the level of residential satisfaction, characteristics of residents, and detailed types of rental housing. The results of this analysis are expected to be used to improve existing public rental housing or develop new types of rental housing to match the characteristics of residential housing for public rental housing. In addition, in the type integration of rental housing currently being promoted, it is necessary to develop a method of providing differentiated services in consideration of the characteristics of tenants as well as the integration of physical housing types.