• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.9 s.180
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• pp.2191-2201
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• 2000

End effects due to sectional deformations of thin-walled beams with closed cross section are analysed by a one-dimensional theory. In particular, end effects associated with warping (out of plane m otion) and distortion (in plane motion) are investigated. The exact solutions as a vector form are newly derived to reveal slowly-decaying nature of the end effects in a thin-walled beam loaded by a couple. Several examples of thin-walled beams under various loading conditions indicate that the local end effect zone due to warping and distortion is approximately ten times the typical beam width.

• Journal of the Korean Society of Visualization
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• v.11 no.1
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• pp.22-27
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• 2013

An investigation into the influence of ultrasonic standing wave on the structural behavior of propane/air premixed flame has been made to get a clue to the combustion reaction acceleration and combustion instability. Visualization technique utilizing the Schlieren photography was employed for the observation of structural variation of the flame reaction zone. Evolutionary characteristics of the flame front were caught by the high-speed Schlieren image, through which local flame velocity of the moving front were analyzed in detail.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2258-2270
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• 2008

After rapid running is begun in domestic, problem by the train wind that was not considered at existent train running appeared. If the High-Speed railway business speed rises by 350km/h in the future, is going to become more big issue. This study conducts an experiment that measure in local about KTX train beside Gyeongbu High-Speed railway track about aerodynamics effect that happen by passage of train and analyzed. In case KTX II runs with the 350km/h speed, forecasted effect that get in the simple vertical surfaces parallel to tracks according to distance from rail center. Compared construction size with structural analysis in case do not consider with case that consider the train wind about soundproofing walls representatively. As a result, proposed wind load standard that apply at soundproofing walls design.

• Proceedings of the KSR Conference
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• 2001.05a
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• pp.281-288
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• 2001

In order to evaluate the effect of impact load at support stiffness transition area, the field estimations are performed at the transition zone between earthwork and bridge on test operation of KTX. Due to differential settlement caused by the variations of track support stiffness, large impact forces are investigated. However, the measured values such as wheel load, rail stress, displacement and acceleration in the transition area shows that the stiffness changes in the transition area are not abrupt, and the stiffness in the infra track structure varies continuously. In this experimental study, the parameters influencing safety of transition area are not governed by partial or local stiffness because cumulative passing loads are not sufficient on test operation of KTX.

• Spatial Information Research
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• v.10 no.4
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• pp.515-532
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• 2002

Planning Support System (PSS), an alternative framework of computer-aided planning system combining geographic information system (GIS), urban models, and visualization tools, has been actively researched and applied in many developed countries. This paper introduces a PSS-based land use change model, What if\ulcorner PSS, by applying it to Chongju City, Korea. This model application study used the spatial database, Restricted Development Zone (RDZ), and other hypothetical land supply- and demand-related policies of Chongju City. The collaborative PSS model supported land use planning process by helping users to speedily and easily create and test policy-oriented scenarios. The study found that the fully operational PSS model was readily applicable and useful to Korean local land use planning. The paper discusses the conceptual model framework, data requirement, application process, model output, and practical usage. This study would be considered as a prototypical approach of PSS-based land use plan making for Korean cities.

• Journal of Information Display
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• v.12 no.2
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• pp.77-83
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• 2011

The memory compression algorithm CCC-LCP (color-count-controlled local color palette) reduces flicker in the liquid crystal display (LCD) overdrive. Its compression ratio is 1:5.4 for 10-bit images, with a 33 dB PSNR peak signal-to-noise ratio and with five times flicker reduction compared with the block truncation coding. The authors' two-alternative forced choice subjective tests proposed two new soundness properties, the 'CMP harmlessness' and 'OD non-lost (or OD liveliness)', to clarify the functional interaction between the overdrive functionality OD and the compression functionality CMP. The tests verified that CCC-LCP is practically applicable (at a 1.2H viewing distance threshold) for 42" 37-ppi WXGA TVs.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.615-621
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• 2005

초고속급 속도를 가지는 광대역통신서비스가 본격화됨에 따라 유선을 이용한 서비스뿐만 아니라 무선을 이용한 광대역서비스도 제공되고 있다. 이러한 초고속광대역서비스를 제공하는 무선시스템중 하나인 B-WLL시스템은 시스템 구성상 서비스구간을 유선을 이용하여야 하는 불편함이 있다. 이를 보완하기 위해서 신규수요지역 서비스 Zone에 유비쿼터스 환경의 지역무선 구축을 고려하였고, 이에 2GHz 및 5GHz의 주파수를 이용, 무선랜 구축을 위한 최적의 셀 설계 방안을 제시하였다.

• Journal of Korean Port Research
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• v.12 no.2
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• pp.195-206
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• 1998

By the rapid expansion of containerization and intermodal transportation in international shipping since the 1970's, the larger containerships have emerged and concentrated their calls at a limited number of ports. Moreover, large-scale container terminals have been built to accommodate the ever-larger containerships, and the mordernization of terminal facilities and many developments in information technology etc. have been brought out. Thus, unlimited competition has been imposed on every terminal with neighbouring ports in Japan, Singapore, Hongkong and Taiwan etc. The purpose of this study is to suggest how the container terminal operators cope with unlimited competition between local or foreign terminals. The results are suggested as follows: First, transshipment cargoes, which the added value is high, is to be induced. Second, the function of storage is given on On-Dock Yard. Third, Berth Pool Operation System is to be introduced, especially in Gamman Container Terminal and Kwangyang Container Terminal. Fourth, the cargo handling charges is to be decided by terminal operator.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1997.10a
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• pp.13-19
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• 1997

Foodborne diseases are serious problems throughout the world, because new pathogens have emerged. Nowadays many students eat school lunch provided by school lunch provided by school lunch program. They are threatened by pathogens transmitted by foods. many school children became victims of foodborne diseases. Most foodborne outbreaks were caused by mishandling foods at food service establishments. Food safety practices of school lunch programs in foreign countries were reviewed. Temperature control is the most critical part of keeping the foods safe. In order to prevent foodbrorne diseases in schools, the managers in charge of school lunch program and officials in charge of food safety of local health department try to make sure that foods are out of danger zone of temperature. Prevention of cross contamination, and sanitization of raw foods and utensils are also emphasized by school lunch program managers and health officials.

• Wind and Structures
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• v.4 no.6
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• pp.455-468
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• 2001

This paper presents recent research on the experimental evaluation of wind loads on low buildings and the recommendations provided in the form of traditional codification. These mainly include the wind loads on buildings with geometries different from those examined in previous studies. This is followed by the evaluation of simulated wind loads on low building roofs. The overall application of a recently proposed simulation methodology for codification purposes is discussed in detail. The traditional codification provides for a group of roof geometries a single peak design pressure coefficient for each roof zone considering a nominal worst-case scenario; this may often lead to uneconomical loads. Alternatively, the presented methodology is capable of providing peak pressure coefficients corresponding to specific roof geometries and according to risk levels; this can generate risk consistent and more economical design wind loads for specific roof configurations taking into account, for instance, directional design conditions and upstream roughnesses.