• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.2
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• pp.213-220
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• 2016

This research aims to develop core technologies for passive carrier (no power in carrier itself) transfer system. The technologies are passive levitation, propulsion, and guidance, which can be great benefits for semiconductor and display manufacturing industries. Passive maglev carrier is necessary to precise position control for quiet and stable transfer operation. However, the structural characteristics of carrier and the installation errors of gap sensors cause the pitch motion. Hence, the controller design in consideration of pitch motion is required. This study deals with the reduction control of carrier pitch motion. PDA controller and PDA controller with pitch control are proposed to compare the pitch angle analysis. The pitch angle and the levitation precision are measured by experiment. Finally, the optimized design of pitch controller is presented and the effects are discussed.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.19 no.1
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• pp.29-37
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• 2011

Last April, Europe was severly damaged as all social and economic activities came to a halt prompted by the cancellation of all flights resulting from volcanic ash. This exemplifies that the meteorology conditions have significant influence on the flights of airplanes. Hence, in this research the influence that the meteorology has on the domestic flights and its characteristics will be examined, and the core meteorological factors that influence flights in each airport will be drawn. In order to do this, statistical analysis on the influence that the meteorology has on flights was carried out in order to analyze the data about flight cancelation and delay and also its cause, primarily based on the Gimpo, Gimhae, and the Jeju airports. As a result, first, the meteorological factors which impact flight cancellation and delay were different among the domestic airports, and second, it was analyzed that fog was the main meteorological factor in the Gimpo airport, strong wind in the Jeju airport, and fog in the Gimhae airport. Third, between the day the flights were cancelled and delayed occurred, and the day that weren't, the fact that there existed a difference among the actual meteorological factors was statistically drawn. With the result of such analysis, meteorological factors pertaining to the cancellation and delay of flights must be considered seperately by each airport and specialized meteorological information must be provided accordingly. Further, when selecting the position of an airport that is to be constructed in the future, implications that there is a definite need for the meteorology effect evaluation based on past meteorology data can be drawn.

• Journal of KIISE
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• v.43 no.11
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• pp.1201-1209
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• 2016

As the use of SNS continues to increase, various related studies have been conducted. According to the effectiveness of the topic model for existing theme extraction, a huge number of related research studies on topic model based analysis have been introduced. In this research, we suggested an automation system to analyze topics of each country and its distribution in twitter by combining world map visualization and issue matching method. The core system components are the following three modules; 1) collection of tweets and classification by nation, 2) extraction of topics and distribution by country based on topic model algorithm, and 3) visualization of topics and distribution based on Google geochart. In experiments with USA and UK, we could find issues of the two nations and how they changed. Based on these results, we could analyze the differences of each nation's position on ISIS problem.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.1-8
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• 2003

Velocity data were acquired at a series of stations in the chordwise direction above a delta wing with leading edge extension, using a triple axis hot film anemometry. Surveys normal to planform yield velocity field data at incidence angle of 24$^{\circ}$and 32$^{\circ}$at a centerline chord Reynolds number of $1.76{\times}10^6$. Experimental results of velocity measurements of mean velocity of three components gave a confidence to quantitative investigate the vortical flow field over a LEX-delta wing with this probe. The present experiments indicated the existence of both wing and LEX vortex where the local mean axial velocity is maximum. It also shown the development of secondary vortex of opposite sign of rotating above the wing surface near the leading edge. The insertion of probe across the flow field was found to have little influence on the position of the vortex core.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.315-324
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• 2009

Public institutions guaranteed exclusive position of core business are likely to be inefficient in management. Past governments made various efforts to innovate public institutions. Participatory government drove innovation of public institutions through Ministry of Planning and Budget, and this innovation policy had problems as followings: shortage of common sense of innovation, lack of understanding of innovation, gradual execution of innovation instead of system innovation for business innovation, lack of consideration of characteristics of various public innovation, overlapping of evaluation system, and nonobjective design of evaluation indicator. MB government has diverse assignments for improvement of these problems as followings: transformation of business mind, voluntary participation of employee, improvement of management system of public institutions, reform of business evaluation system, promotion of internal competition, and construction of performance based business system. What is the most important point for successful reform of public institution is to achieve the support of general public with effective action plan and substantial programs.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.297-306
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• 2010

A city is the space which has a various historical experiment and memories. From these social and cultural environment, regional competitions through the introduction and settlement of a local self-government have been important in city marketing. For city development, a serial activation policies are come and in this process the native history and cultures have recognized as the core tool of cities. For possession of city competition, we have developed the cities' tangible and/or intangible cultural properties and make full use of a attractive asset. The city identity is established and the opportunity of a special space is made. This city identity has been dependent on spending time. We suggest the strategy for the historical and cultural city image through the historical element and the development of program for the promotion of publicity activities. The preservation and application of the modern architectures as the cultural and historical element promote the city image and build the position of city identity. We suggest the city marketing application strategy for the implication on the sustainable reproductive city.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.2
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• pp.1-8
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• 2000

An attempt was made to develop commercially pure titanium frames of glasses with a high-precision laser beam welding machine, in which a resonator with 12kw of the peak power and 200 W of maximum mean power has the capacity of variable in the range of 0.08~10 ms pulse width. In addition the optical fiber beam transmission with 400 ${\mu}{\textrm}{m}$ of the core diameter and a weld chamber to contain specimens in the inert gas atmosphere were also designed and used. In the present study. titanium frames of glasses parts such as temple plus spring hinge. bridge and top bar were experimentally manufactured by utilizing the optimum welding parameters with the optical fiber of GI 400 ${\mu}{\textrm}{m}$, 2.9J energy per pulse, and focussing position for Tee and butt joints. The titanium welded joints with laser beam welding did not reveal any severe weld defects or weld bead appearance except some pores in the weld section.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.3
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• pp.1-9
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• 2009

Through 'Local Theme Science Museum' aid program that is one of emphasis promotion strategic project by 2007 'Science.Technology.Cultural Project Plan', raises status of scientific technique by national core ability because all people expand base that understand and support scientific technique, and forms a social atmosphere which is scientific technique is important which scientific technique can be spread widely on national life and society whole, and proceeds target that expand local science museum facilities by a base of local science culture spreading and popularization. Accordingly, to plan balanced regional development and utilize to an advanced base of local science culture spreading because offer a science culture experience opportunity to local inhabitants, 'Local theme science museum' project is doing for that establish more 100 science museums for national.public.private institution in whole country until 2012 year. Support 39 projects to 2008 from 1999 thereby, in January, 2009, 13 'Local theme science museum' is opened and operated. This study examined arrangement preferentially about 'Science.Technology.Cultural Project Plan' that is background of 'Local theme science museum' project. Since surveying science museum which is on opening and operation at the present and analyzed actual conditions and facilities and investigated specification necessity and direction of 'Local theme science museum'. Hereafter, to seek plan for propriety of project by characteristic and difference of 'Local theme science museum' is purpose of this study. Now, need set and promotion of following specification direction for right activation of proceeding 'Local theme science museum' by each area. First, differentiation of theme and justifiability of building, Second, propriety of site position, Third, maximization of synergy effect by mixing concept of 'Specialized Economic Zone for Regional Developmental Policy' and Ecomuseum's 'Theme center'.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.239-243
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• 2009

A various regional competitions through the introduction and settlement of a local self-government have been important in city marketing. For city developing, a serial activation polices are come and in this process the native history and cultures have recognized as the core tool of cities. For possession of city competition, we have developed the ciies's tangible and/or intangible cultural properties and make full use of a attractive asset. The city identity is estibilished and the opportunity of a special space is made. This city identity has been dependent on spending time. We suggest the strategy for city image through the historical element and the development of program for the promotion of publicity activities. The preservation and application of the modern architectures as the cultural and historical element promote the city image and build the position of city identity. We suggest the city marketing for the implication on the sustainable reproductive city.

• Tunnel and Underground Space
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• v.16 no.6 s.65
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• pp.451-466
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• 2006

Analysis of slope behavior concerning the structural characteristics of field rock mass can be processed by virtue of borehole information of joint orientation and position acquired from DOM drilled core. Anticipated sliding potential of pre-failed rock slope is analyzed and the regional slope instability is investigated by inspecting the hazardous joints and blocks the traces of which is projected on the cut-face. Cross section has been set at the center of rock slope and the traces of both joints and tetrahedral blocks, which potentially can induce the slope failure, are drawn to investigate the failure modes and the triggering mechanism. Automated monitoring system has been established to measure the slope movement and especially, inclinometer has been installed inside DOM borehole to analyze the slope movement by considering the internal rock structure. Algorithms for predicting the slope failure time have been reviewed and the significance of heavy rainfall on the slope behavior has been investigated.