• Wind and Structures
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• 제24권5호
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• pp.465-480
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• 2017

Modelling an equilibrium atmospheric boundary layer (ABL) in computational wind engineering (CWE) and relevant areas requires the boundary conditions, the turbulence model and associated constants to be consistent with each other. Among them, the inflow boundary conditions play an important role and determine whether the equations of the turbulence model are satisfied in the whole domain. In this paper, the idea of modeling an equilibrium ABL through specifying proper inflow boundary conditions is extended to the SST $k-{\omega}$ model, which is regarded as a better RANS model for simulating the blunt body flow than the standard $k-{\varepsilon}$ model. Two new sets of inflow boundary conditions corresponding to different descriptions of the inflow velocity profiles, the logarithmic law and the power law respectively, are then theoretically proposed and numerically verified. A method of determining the undetermined constants and a set of parameter system are then given, which are suitable for the standard wind terrains defined in the wind load code. Finally, the full inflow boundary condition equations considering the scale effect are presented for the purpose of general use.

• Wind and Structures
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• 제18권5호
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• pp.567-598
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• 2014

In this paper, wind induced aerodynamic loads on a standard tall building have been evaluated through large-eddy simulation (LES) technique. The flow parameters of an open terrain were recorded from the downstream of an empty boundary layer wind tunnel (BLWT) and used to prescribe the transient inlet boundary of the LES simulations. Three different numerically generated inflow boundary conditions have been investigated to assess their suitability for LES. A high frequency pressure integration (HFPI) approach has been employed to obtain the wind load. A total of 280 pressure monitoring points have been systematically distributed on the surfaces of the LES model building. Similar BLWT experiments were also done to validate the numerical results. In addition, the effects of adjacent buildings were studied. Among the three wind field generation methods (synthetic, Simirnov's, and Lund's recycling method), LES with perturbation from the synthetic random flow approach showed better agreement with the BLWT data. In general, LES predicted peak wind loads comparable with the BLWT data, with a maximum difference of 15% and an average difference of 5%, for an isolated building case and however higher estimation errors were observed for cases where adjacent buildings were placed in the vicinity of the study building.

• KIEAE Journal
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• 제11권5호
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• pp.55-67
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• 2011

The purpose of this research is to find applicable design characteristics and methods of communal spaces in vertical urban multi-family housing. With this goal, several overseas' multi-family housing projects are selected and their communal spaces are identified. The design characteristics of the communal spaces are analyzed with a special focus on the territories such as an individual unit boundary, building interior and exterior boundary. In terms of the framework for analysis, territoriality, openness, and unique characteristics are reviewed. As a result, the communal spaces are created using various spatial composition methods such as addition, subtraction, connection, extension, accumulation, and isolation. The communal space programs are integrated in plans and sections throughout the buildings. Visual openness and connection with surrounding urban environments are articulated by void spaces, transparent and translucent building materials, green spaces, and applications of graphical images. Communal identities and aesthetics are emphasized by unique building forms and space arrangements. The uses of finish materials, colors, objects, and images add strong characters to the communal spaces. For a further research, it is necessary to combine a design method study with residents' behaviors and community interactions.

• Wind and Structures
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• 제34권5호
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• pp.395-405
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• 2022

Tornado-induced damages to high-rise buildings and low-rise buildings are quite different in nature. Tornado losses to high-rise buildings are generally associated with building envelope failures while tornado-induced damages to low-rise buildings are usually associated with structural or large component failures such as complete collapses, or roofs being torn off. While studies of tornado-induced structural damages tend to focus mainly on low-rise residential buildings, transmission towers, or nuclear power plants, the current rapid expansion of city centers and development of large-scale building complexes increases the risk of tornadoes impacting tall buildings. It is, therefore, important to determine how tornado-induced load affects tall buildings compared with those based on synoptic boundary layer winds. The present study applies an experimentally simulated tornado wind field to the Commonwealth Advisory Aeronautical Research Council (CAARC) building and estimates and compares its pressure coefficient effects against the Atmospheric Boundary Layer (ABL) flow field. Simulations are performed at the Wind Engineering, Energy and Environment (WindEEE) Dome which is capable of generating both ABL and tornadic winds. A model of the CAARC building at a scale of 1:200 for both ABL and tornado flows was built and equipped with pressure taps. Mean and peak surface pressures for TLV flow are reported and compared with the ABL induced wind for different time-averaging. By following a compatible definition of the pressure coefficients for TLV and ABL fields, the resulting TLV pressure field presents a similar trend to the ABL case. Also, the results show that, for the high-rise building model, the mean and 3-sec peak pressures are larger for the ABL case compared to the TLV case. These results provide a way forward for the code implementation of tornado-induced pressures on high-rise buildings.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2005년도 추계학술대회 논문집
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• pp.46-49
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• 2005

Vents at outer walls of a large factory building are very important for natural ventilation. But, if a full-open vent is used, rain comes through the vents. We tried to utilize the natural ventilation effectively using a louver. A 1/120 scale-down building model was placed inside an atmospheric boundary layer simulated in a wind tunnel test section. The effect of louver angle on the ventilation flow inside the factory building was investigated experimentally. Instantaneous velocity fields inside the building model were measured using a 2-frame PIV system with varying the louver angles ($\theta=20^{\circ},\;40^{\circ},\;60^{\circ}$). For the case of $\theta=60^{\circ}$, as the incoming flow into the factory building increases, the inside velocity distribution becomes uniformly.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.167-168
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• 2014

Building destruction can be occurred by decreasing of structural stability and deformation according to fire. Especially, a structural behavior of beam can be shown a slightly difference by beam types. In this paper, an evaluation of the structural stability of beam made of ordinary structural steel designed by fixed and simple boundary condition was done by an analytic method using mechanical properties of SS 400 and an heat transfer theory.

• 한국정보통신학회논문지
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• 제23권11호
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• pp.1343-1350
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• 2019

윤곽선 이미지를 시계열로 변환하는 작업은 빠르고 상호작용 방식이 매우 중요한 대용량 이미지 데이터베이스에서도 윤곽선 매칭 수행을 가능 할 수 있게 만든다. 최근 연구에서는 윤곽선 이미지를 시계열 데이터로 변환하여 부분 노이즈제거를 고려하면서 빠르게 매칭을 수행하려는 시도가 있었다. 본 논문에서는 성능 향상을 위해 임의의 노이즈제거를 위해 임의의 모든 노이즈제거 매개 변수를 고려한 색인 구축 방법을 제안한다. 이는 가능한 모든 노이즈제거 매개 변수에 따른 부분 노이즈제거를 고려해야하기 때문에 어려운 문제이다. 본 논문에서는 다차원 색인인 R*-tree를 사용하여 모든 가능한 노이즈제거 매개 변수에 의한 최소 경계 영역(MBR)을 구성하여 효율적인 단일 생성 알고리즘을 제안한다. 다양한 실험 결과, 제안한 색인 기반 매칭 방법은 검색 성능을 최대 46.6 ~ 4023.6 배나 향상시킨다.

• 한국실내디자인학회논문집
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• 제18권6호
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• pp.176-183
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• 2009

This study was intended to define the spatial concept of the boundary structure of the architectural space as well as evaluate the Hyangdan which well represents the features of Korean traditional building in such a way of reviewing the building structure of Korean traditional residential space. The boundary is categorized into visible boundary and invisible boundary which was also functionally classified into the features of isolating, passing, mediating and overlapping. The major elements comprising the boundary structure was analyzed by the characteristic of the pattern so as to define them as the concept of surrounding, duality, hierarchism, continuity and overlapping. Based on such concepts, a boundary structural characteristics of Hyangdan were reevaluated and outlined as follows. The surrounding feature was seen through the outer side of the structure surrounded, two courtyards and eaves, and a duality showing both the closure of main house and openness of detached house was seen through the characteristics of surrounding structure. And the continuous activities toward the inner room and the empty space to link them in a systematic way and repeatedly aligned rooms reveal the overlapping as continuous and transitional space. And finally, an elevated stylobate demonstrates the hierarchical features of the structure.

• Spatial Information Research
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• 제15권1호
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• pp.53-65
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• 2007

지상라이다는 고정도의 3차원 영상을 제공하고 레이저빔을 현장이나 대상물에 발사하여 짧은 시간에 수백만점의 3차원좌표를 기록할 수 있는 최신 측량장비로서 다양한 응용분야에서 두각을 나타내고 있다 본 연구에서는 지상라이다를 이용한 아파트 건축물의 3차원 경계 추출을 다루었다. 실험측량결과 지상라이다로 아파트건축물의 3차원 경계를 신속하게 추출할 수 있었지만 지상기반시스템이므로 건축물 지붕 그리고 나무, 전주 때문에 건축물 저층부에서는 이것이 쉽지 않았다. 향후 토탈스테이션, 지상라이다, 항공라이다와 항공사진측량과의 결합을 통해 효율적인 3차원공간정보 획득이 가능할 것으로 기대된다.

• 한국실내디자인학회논문집
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• 제19권2호
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• pp.81-89
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• 2010

The problem of defining the relationship between interior space and exterior envelope of a building has long been a challenging task in the field of architecture throughout its history. This research chronologically reviews some of the important turning points in various schools of thoughts concerning construction of exterior envelope, with focus on how they influenced and altered the formation of our interior environment. This research also stipulates on how technological advance in the late 20th century laid grounds for a new type of interior-exterior relations in architecture through creation of flexible and ambiguous boundary conditions. The focus of this qualitative research will be on contemporary works of Japanese architects Toyo Ito, SANAA, and related group of architects who address the issues of transparency, flexible interior layout, buffer zones, structural facade, and neutralized (homogeneous) space that produces spatial quality of non-linear, non-hierarchical, and de-materialized space as a direct alternative to modern principles of space making.