• Journal of Korean Neurosurgical Society
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• v.64 no.2
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• pp.289-296
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• 2021

Objective : Though the operating microscope (OM) has been the standard optical system in neurosurgery, a new technology called three-dimensional (3D) exoscope has emerged as an alternative. Herein, two types of 3D exoscopes for brain tumor surgery are presented. In addition, the advantages and limitations compared with the OM are discussed. Methods : In the present study, 3D exoscope VOMS-100 or VITOM 3D was used in 11 patients with brain tumor who underwent surgical resection; the Kinevo 900 OM was used only in emergency. After completion of all surgeries, the participants were surveyed with a questionnaire regarding video image quality on the display monitor, handling of equipment, ergonomics, educational usefulness, 3D glasses, and expectation as a substitute for the OM. Results : Among 11 patients, nine patients underwent neurosurgical resection with only 3D exoscope; however, two patients required additional aid with the OM due to difficulty in hemostasis. Regarding video image quality, VITOM 3D was mostly equivalent to the OM, but VOMS-100 was not. However, both 3D exoscopes showed advantages in accessibility of instruments in the surgical field and occupied less space in the operating theater. Differences in ergonomics and educational usefulness between the exoscopes were not reported. Respondents did not experience discomfort in wearing 3D glasses and thought the exoscopes could be currently, and in the future, used as a substitute for the OM. Conclusion : Although many neurosurgeons are not familiar with 3D exoscopes, they have advantages compared with the OM and similar image quality. Exoscopes could be a substitute for OM in the future if some limitations are overcome.

• Journal of Convergence for Information Technology
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• v.9 no.2
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• pp.115-120
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• 2019

Chinese xian-xia films is a new genre that occurred through the fusion of the genre of martial arts and fantasy. This study analyzed the development of xian-xia films and the space aesthetics of xian-xia films through the miseenscene of the journey to the west films. In particular, the space for xian-xia in the films is divided into the human, urinary, heaven world and the space of conflict. It looks like the fantastic Middle Earth that Tolkien presented, however it is discriminatory in that it shows a highly Chinese appearance and overlapping world centered on the natural environment (the world of Mountains and Livers), such as mountains, deserts, caves, and grasslands, which usually appears in traditional martial arts history. Resently, the boom of journey to the west films is regarded as the change of the Chinese film industry under the influence of the development of IP (Intellectual Property) industry and the western fantasy genre in the 21st century China. This change marks the birth of the new Chinese fantasy "xian-xia" genre with the spirit of the present era that transcends the original world of journey to the west through the hybridization of the genre.

• Korean Institute of Interior Design Journal
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• v.14 no.6 s.53
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• pp.3-11
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• 2005

With development of digital technology and build-up of global network in the 21st century, Korea has recklessly accepted Western information and culture in recent years, thus causing damages to out identity. In the situation, restoration and development of traditions in a modern way will contribute to the creation of contemporary interiors. This study has analyzed and assessed the process through which traditional decorative elements have applied to contemporary interior decorations over the past ten years with a view to identify the trend of expressing traditional elements in comtemporary interiors. Designs that have applied traditional elements in a transfigure expression method amounted to 77 pieces, accounting for $43\%$ of the total investigated 178 designs, which was followed by 48 designs ($27\%$) of metaphor expression method and 39 designs ($22\%$) of symbol expression method, which express the tradition as interpreted by the designer. Designs that have adopted direct expression method amounted to no more than 14 pieces, accounting only for $8\%$ of the total designs. This result suggests that transformative, metaphoric and symbolic expressions that simplify or transform the original forms we more frequently used In the applications of traditional elements to modern interiors rather than directive expression that reproduces the original form as it was.

• International Journal of Aeronautical and Space Sciences
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• v.4 no.1
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• pp.53-62
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• 2003

In this study, nonlinear aeroelastic characteristics of an supersonic missile wing with strong shock interferences are investigated. The missile wing model has a freeplay structural nonlinearity at its pitch axis. To practically consider the effects of freeplay structural nonlinearity, the fictitious mass method is applied to structural vibration analysis based on finite element method. Nonlinear aerodynamic flows with unsteady shock waves are also considered in supersonic flow regions. To solve the nonlinear aeroelastic governing equations including the freeplay effect, a modal-based coupled time-marching technique based on the fictitious mass method is used in the time-domain. Various aeroelastic computations have been performed for the nonlinear wing structure model. Linear and nonlinear aeroelastic analyses have been conducted and compared with each other in supersonic flow regions. Typical nonlinear limit cycle oscillations and phase plots are presented to show the complex vibration phenomena with simultaneous fluid-structure nonlinearities.

• Journal of Digital Contents Society
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• v.14 no.2
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• pp.179-189
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• 2013

With the rapid development of information technology in 21st century, networks are being used with various devices. Most human actions are processed through cyber space, and it is no longer separate from daily life; it has changed into one of the most important aspects of human life. Unfortunately, in cyber space, certification method has not only technical problems, but also ethological problems. Many users seemed to use the same password throughout several sites. And for a long period they refused to change it or made a small change from the earlier password. This research aims to discuss general factors of choosing and using passwords within information security through statistical analysis.

• Aerospace Engineering and Technology
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• v.7 no.1
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• pp.91-98
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• 2008

Since the 1st space race between the United States and Soviet Union during the 1960s, we are competing 2nd space race to occupy the Lunar territory. Since the United States announced to construct the Lunar Base by the end of 2020, ED, Japan, and China launched Lunar explorers successfully. Even India is planning to launch a Lunar explorer in 2008. Korean government also announced that the Korea will launch first Lunar explorer in 2020. In this research Lunar mission trajectory design which will be fundamental data for Lunar mission with variable low thrust and Lunar mission trajectory which has a similar mission specification to SMART-1 are presented.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.6
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• pp.623-633
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• 2020

As the time spent in indoor space has increased, the demand for services targeting indoor spaces also continues to increase. To provide indoor spatial information services, the construction of indoor spatial information should be done first. In the study, a method of generation IndoorGML, which is the international standard data format for Indoor space, from existing BIM data. The characteristics of IFC objects were investigated, and objects that need to be converted to IndoorGML were selected and classified into objects that restrict the expression of Indoor space and internal passages. Using the proposed method, a part of data set provided by the BIMserver github and the IFC model of the 21st Century Building in University of Seoul were used to perform experiments to generate PrimalSpaceFeatures of IndoorGML. As a result of the experiments, the geometric information of IFC objects was represented completely as IndoorGML, and it was shown that NavigableBoundary, one of major features of PrimalSpaceFeatures in IndoorGML, was accurately generated. In the future, the proposed method will improve to generate various types of objects such as IfcStair, and additional method for automatically generating MultiLayeredGraph of IndoorGML using PrimalSpaceFeatures should be developed to be sure of completeness of IndoorGML.

• The Journal of the Korea Contents Association
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• v.10 no.9
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• pp.421-431
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• 2010

Sustainable development is the main stream of urban development in 21st century. Also, in contemporary cultural space, it is the pivotal paradigm that the development of culture complex and mixture of cultural space, educational facilities, information technology and public space. So, the purpose of this paper lies in presentation for building culture complex belt for innovation city. For this purpose, this paper has reviewed the developmental trend of cultural facilities, has analyzed cultural environment of Naju city, has set the vision and the strategy for Naju innovation city up, and finally has suggested and planned the method of culture complex belt for sustainable new town development.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.541-549
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• 2003

A basic experimental study was conducted in order to find the optimum combustion control technology to decrease the thermal NO$_{x}$, by applying the catalytic combustion method with natural gas. NO$_{x}$ emission increased with increasing space velocity due to temperature rising in the furnace. In order to overcome the low resistance to high temperature, secondary air was supplied to the CST combustor. The following secondary fuel formed combustible mixture in part, which resulted in steep increase of the exiting temperature of the 2nd catalyst bed. It led to the more generator of NO$_{x}$, 30∼60% of the 1 st catalyst bed. It might be due to the potential increase of thermal NO$_{x}$.

• Journal of the Korean Mathematical Society
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• v.32 no.2
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• pp.363-370
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• 1995

A famous result of Chow and Robbins [8] asserts that if ${X_n, n \geq 1}$ are independent and identically distributed (i.i.d.) random variables with $E$\mid$X_1$\mid$ = \infty$, then for each sequence of constants ${M_n, n \geq 1}$ either $$ (1) lim inf_{n\to\infty} $\mid$\frac{M_n}{\sum_{j=1}^{n}X_j}$\mid$ = 0 almost certainly (a.c.) $$ or $$ (2) lim sup_{n\to\infty}$\mid$\frac{M_n}{\sum_{j=1}^{n}X_j}$\mid$ = \infty a.c. $$ and thus $P{lim_{n\to\infty} \sum_{j=1}^{n}X_j/M_n = 1} = 0$. Note that both (1) and (2) may indeed prevail.