• Structural Engineering and Mechanics
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• 제45권4호
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• pp.543-568
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• 2013

This study explores the floor micro-vibrations induced by the automated guided vehicles (AGVs) in liquid-crystal-display (LCD) factories. The relationships between moving loads and both the vehicle weights and speeds were constructed by a modified Kanai-Tajimi (MKT) power spectral density (PSD) function whose best-fitting parameters were obtained through a regression analysis by using experimental acceleration responses of a small-scale three-span continuous beam model obtained in the laboratory. The AGV induced floor micro-vibrations under various AGV weights and speeds were then assessed by the proposed regressional MKT model. Simulation results indicate that the maximum floor micro-vibrations of the target LCD factory fall within the VC-B and VC-C levels when AGV moves at a lower speed of 1.0 m/s, while they may exceed the acceptable VC-B level when AGV moves at a higher speed of 1.5 m/s. The simulated floor micro-vibration levels are comparable to those of typical LCD factories induced by AGVs moving normally at a speed between 1.0 m/s and 2.0 m/s. Therefore, the numerical algorithm that integrates a simplified sub-structural multi-span continuous beam model and a proposed regressional MKT moving force model can provide a satisfactory prediction of AGV-induced floor micro-vibrations in LCD factories, if proper parameters of the MKT moving force model are adopted.

• 한국구조물진단유지관리공학회 논문집
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• 제9권1호
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• pp.197-204
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• 2005

다목적 바닥 레벨조인트는 레일의 레벨링과 조립이 용이하고 조인트에서 변형 흡수가 가능한 공법으로 최근 국내에서 개발되었다. 앞서 수행된 연구결과를 통하여 본 공법의 구성부재인 지지대, 레일, 그리고 레일+지지대의 구조적 특성은 만족스런 결과를 얻을 수 있었다. 따라서 본 연구에서는 콘크리트를 타설한 바닥 레벨조인트의 변형흡수 능력을 평가하기 위해 인장 또는 압축변형을 유발시킨 실험적 연구를 실시하였다. 또한 다목적 바닥 레벨 조인트를 설치한 대상구조물을 선정하여 해석적 연구를 수행함으로서 다목적 바닥 레벨 조인트의 변형성능을 정량적으로 파악하였다. 실험과 해석연구를 통하여 다목적 바닥 레벨조인트는 요구되는 변형수요에 비하여 충분한 변형흡수 능력을 확보하고 있는 것으로 나타나났다.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2002년도 추계학술발표대회
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• pp.301-306
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• 2002

In Japan, the vacancy rates of office buildings have been at high in big cities since 1992. This problem is especially acute in Tokyo, where it is estimated that over 2.27 million square meters of office floor area will be oversupplied in 2003: big urban redevelopment projects will be completed in 2003. Under these circumstances, International Cooperative Research and Development on Sustainable Urban Management by Conversion of Buildings, called “SUMCOB”, has been carried out. This research aims to regenerate urban areas by converting redundant offices into flats, although instances of conversion are still very few in Japan. This paper introduces part of current results by SUMCOB, and discusses legal problems with conversion and basic capacity of vacant offices in Tokyo. It has been confirmed that there are no constraints concerned with Real Estate Registration Law (although it requires the change of the registration after conversion). and City Planning Law. However, some criteria are incompatible with Building Standard Law and Fire Service Law if the use of the building is changed from offices to flats. Typical incompatibility between offices and flats is lightening. If the buildings do not satisfy criteria for flats, the cost of renovation works for conversion will increase. To examine the basic capacity of vacant office buildings for conversion, field surveys in Tokyo have carried out at three areas: Kodenmacho (Chuo-ku), Toranomon (Minato-ku), and Iwamonocho (Chiyoda-ku). They are typical office areas that are included in center core of Tokyo. In Chuo-ku, the oldest commercial area in Tokyo, textile merchants have been located their headquarters. In Minato-ku, many rental office buildings have been located and several large scale redevelopments are advancing. Chiyoda-ku includes Marunouchi area, which is the prime office area in Japan. Thirty percent of the buildings in survey areas suffer from over twenty percent vacant floor rate, and fifty five percent were constructed before 1990. Especially most of buildings over forty percent vacant floor rate were constructed in 1980s. Vacant office problems haven't been seen in old buildings in Tokyo yet. The number of dwelling units made from office space will influence the conversion scheme. Seventy percent of the office buildings in survey areas have floor area of less than two hundred square meters. If they have been subdivided into two bedrooms type or three bedrooms type, the number of dwelling units in a floor would be less than three. The difficulty of conversion planning derives from frontage size, depth size, and their proportion. The five categories are proposed to grasp actual requirements for converting offices into flats.

• 한국실내디자인학회논문집
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• 제23권2호
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• pp.12-20
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• 2014

The purpose of this study is to analyze the general patterns of the floor plans and space of Usonian house which designed by Frank Lloyd Wright. this thesis can be summarized as follows : 1) F.L.Wright's houses mostly used simple geometric shapes as the basis for most of his architectural designs. In his early works, his typical floor plans were square or rectangular shapes, which gradually were transformed into various kinds of shape to make the adjustment of location of the site and shape. 2) The general patterns of floor plans of his U-houses were L-shaped or straight shaped using a $4{\times}4$ grid system. Most of U-houses consisted of 3 space: living room, workspace(Kitchen) & dining, and bedroom. Among them, a workspace worked as core role in each house. 3) Even though solid wall is the opposite concept of the transparent glass but most U-houses were designed to have solid walls on one side to provide a gallery space(to secure habitability of resident) and transparent glass walls used on the other side to connect between interior space and natural space of exterior. 4) The cantilever have not been used before Usonian house but F.L.Wright used it which take charge of functions as transfer space between inside space and outside space. 5) F.L.Wright saw the nature as a truth, so he thought the interior space would be natural and all houses must be able to adjust to the natural environment.

• 한국시뮬레이션학회논문지
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• 제25권3호
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• pp.41-51
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• 2016

본 연구는 보행자의 물리적 특성(크기, 모양, 자세 등)을 적용한 개선된 플로어 필드 모델(Floor field model; FFM)을 소개하고, 개선된 모델과 널리 알려진 다른 피난시뮬레이션 모델과의 비교를 통해 FFM의 한계점 파악 및 개선된 모델의 특징을 분석하고자 한다. FFM은 셀룰라 오토마타(Cellular automata)를 이용한 대표적 미시적 관점 보행 모델이지만 보행자의 크기, 모양, 자세 등의 물리적 특성을 세밀하게 반영하지 않는다. 이로 인해 보행자들 간의 충돌, 마찰 등의 현상을 모델링하기 어려우며 결과적으로 다른 모델들과 비교하였을 경우에 매우 짧은 대피 시간을 산출하고 있다. 본 연구는 물리적 현상을 반영할 수 있는 개선된 FFM을 제시하며, 개선된 모델과 기존 FFM, 시뮬렉스(Simulex), 패스파인더(Pathfinder) 등 다른 모델들과의 비교 실험을 수행하였다. 실험은 실제 캠퍼스 건물의 일부 공간을 대상으로 진행되었으며, 대피 인원의 변화에 따른 대피 양상의 비교와 각 출구별 대피 양상의 비교가 수행되었다. 이를 통해 FFM에서는 반영되지 않던 물리적 현상들이 개선된 모델에서는 상용 모델 수준으로 적용되는 점과 특히 시뮬렉스와 유사한 형태의 대피 양상을 보임을 확인하였다.

• 제어로봇시스템학회논문지
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• 제14권12호
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• pp.1294-1301
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• 2008

Under passive RFID environment, this paper presents a new localization of a mobile robot traversing over the floor covered with tags, which is superior to existing methods in terms of estimation performance and cost effectiveness. Basically, it is assumed that a mobile robot is traveling along a series of straight line segments, each segment at a certain constant velocity, and that the number of tags sensed by a mobile robot at each sampling instant is at most one. First, for a given line segment with known starting point, the velocity and position of a mobile robot is estimated using the spatial and temporal information acquired from the traversed tag. Some discussions are made on the validity of the basic assumptions and the localization for the initial segment with unknown starting point. Second, for a given tag distribution density, the optimal tag arrangement is considered to reduce the position estimation error as well as to make easy the tag attachment on the floor. After reviewing typical tag arrangements, the pseudorandom tag arrangement is devised inspired from the Sudoku puzzle, a number placement puzzle. Third, through experiments using our passive RFID localization system, the validity and performance of the mobile robot localization proposed in this paper is demonstrated.

• Steel and Composite Structures
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• 제28권3호
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• pp.319-329
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• 2018

The field around additional cutout of the floor beam web in orthotropic bridge deck was subjected to high stress concentration, especially the weld toe between floor beam and U shaped rib and the free edge of the additional cutout. Based on different considerations, different geometrical parameters of additional cutout were proposed in European, American and Japanese specifications, and there remained remarkable differences among them. In this study, considering influence of out-of-plane deformation of floor beam web and U shaped rib, parameter analysis for additional cutout under typical load cases was performed by fine finite element method. The influence of additional cutout shape and height to the stress distribution around the additional cutout were investigated and analyzed. Meanwhile, the static and fatigue test on this structure details was carried out. The stress distribution was consistent with the finite element analysis results. The fatigue property for additional cutout height of 95mm was slightly better than that of 61.5 mm.

• 한국실내디자인학회논문집
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• 제22권1호
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• pp.274-282
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• 2013

This study aims to investigate planning characteristics of common and living space in the dormitory buildings on campus in Chungcheong province. A document research method was used to analyze and classified into floor-plan, zoning and area. Also site visits were conducted at 8 dormitory buildings of 4 universities, and drawings were collected and compared for this research. The results of this study were as follows; 1)Most floor plans of public spaces had corridor types and integrated public space types. The typical floorplan of living space was 2person-1bedroom and apartment type which shared livingroom, bathroom, restroom and shower between bedrooms. The living space type of dormitory buildings was more complex and growth in size. Unit community combined 2-4person per 1bedroom in floor plan can help student with identity and affiliated formation. 2)The types of the spatial composition in public spaces were devided into three zones; study, living and administrative zones such as seminar room, public bathroom and storage, etc. This results shows that various types of public space for the improvement of community of small group has recently become more important than basic sanitary space in public space of dormitory buildings on campus.

• 한국산학기술학회논문지
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• 제8권3호
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• pp.620-626
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• 2007

본 연구는 셋백에 관한 예비조사를 통하여 셋백의 정의와 셋백발생의 배경 및 기능 등을 파악하고 셋백 사례들에 대한 분석의 틀을 물리적인 특성, 주요 발생 요인, 그리고 셋백유형의 세 가지 범주로 나누어 각 범주별 분석 항목들과 산정식들을 제시함으로써 셋백에 관한 분석의 체계를 마련하고자 하였다. 또한 이를 서울지역 초고층 주거건물의 사례들에 적용하여 기존 사례들에서 이루어진 셋백의 특징들과 한계점을 제시하였다.

• 한국지진공학회논문집
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• 제24권4호
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• pp.179-187
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• 2020

Seismic qualification of equipment including piping is performed by using floor response spectra (FRS) or in-structure response spectra (ISRS) as the earthquake input at the base of the equipment. The amplitude of the FRS may be noticeably reduced when obtained from coupling analysis because of interaction between the primary structure and the equipment. This paper introduces a method using a modal synthesis approach to generate the FRS in a coupled primary-secondary system that can avoid numerical instabilities or inaccuracies. The FRS were generated by considering the dynamic interaction that can occur at the interface between the supporting structure and the equipment. This study performed a numerical example analysis using a typical nuclear structure to investigate the coupling effect when generating the FRS. The study results show that the coupling analysis dominantly reduces the FRS and yields rational results. The modal synthesis approach is very practical to implement because it requires information on only a small number of dynamic characteristics of the primary and the secondary systems such as frequencies, modal participation factors, and mode shape ordinates at the locations where the FRS needs to be generated.