• Earthquakes and Structures
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• v.6 no.1
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• pp.71-87
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• 2014

Interaction between closely-spaced buildings subject to earthquake induced strong ground motions, termed in the literature as "seismic pounding", occurs commonly during major seismic events in contemporary congested urban environments. Seismic pounding is not taken into account by current codes of practice and is rarely considered in practice at the design stage of new buildings constructed "in contact" with existing ones. Thus far, limited research work has been devoted to quantify the influence of slab-to-slab pounding on the inelastic seismic demands at critical locations of structural members in adjacent structures that are not aligned in series. In this respect, this paper considers a typical case study of a "new" reinforced concrete (R/C) EC8-compliant, torsionally sensitive, 7-story corner building constructed within a block, in bi-lateral contact with two existing R/C 5-story structures with same height floors. A non-linear local plasticity numerical model is developed and a series of non-linear time-history analyses is undertaken considering the corner building "in isolation" from the existing ones (no-pounding case), and in combination with the existing ones (pounding case). Numerical results are reported in terms of averages of ratios of peak inelastic rotation demands at all structural elements (beams, columns, shear walls) at each storey. It is shown that seismic pounding reduces on average the inelastic demands of the structural members at the lower floors of the 7-story building. However, the discrepancy in structural response of the entire block due to torsion-induced, bi-directionally seismic pounding is substantial as a result of the complex nonlinear dynamics of the coupled building block system.

• International Journal of High-Rise Buildings
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• v.6 no.3
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• pp.227-235
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• 2017

This paper describes some of the challenges for structural design of a mid-story seismic isolated high-rise building, which is located near Tokyo station, completed in 2015. The building is a mixed-use complex and encompasses three volumes: one substructure including basement and lower floors, and a pair of seismic isolated superstructures on the substructure. One is a 136.5m high Main Tower (office use), and the other is a 98.5 m high South Tower (hotel use). The seismic isolation systems are arranged in the $3^{rd}$ floor of the Main Tower and $5^{th}$ floor of the South Tower, so that we call this isolation system as the mid-story seismic isolation. The primary goal of the structural design of this building was to secure high seismic safety against the largest earthquake expected in Tokyo. We adopted optimal seismic isolation equipment simulated by dynamic analysis to minimize building damage. On the other hand, wind-induced vibration of a seismic isolated high-rise building tends to be excited. To reduce the vibration, the following strategies were adopted respectively. In the Main Tower with a large wind receiving area, we adopted a mechanism that locks oil dampers at the isolation level during strong wind. In the South Tower, two tuned mass dampers (TMDs) are installed at the top of the building to control the vibration. In addition, our paper will also report the building performance evaluated for wind and seismic observation after completion of the building. In 2016, an earthquake of seismic intensity 3 (JMA scale) occurred twice in Tokyo. The acceleration reduction rate of the seismic isolation level due to these earthquakes was approximately 30 to 60%. These are also verified by dynamic analysis using observed acceleration data. Also, in April 2016, a strong wind exceeding the speed of 25m/s occurred in Tokyo. On the basis of the record at the strong wind, we confirmed that the locking mechanism of oil damper worked as designed.

• Korean Journal of Construction Engineering and Management
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• v.10 no.1
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• pp.69-77
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• 2009

Recently, a research of the urban regeneration has been performed very actively. This is one of the efforts to resolve various social and economic problems coming from the existing deteriorated building and facilities by new urban development or redevelopment. However, an urban regeneration has a characteristic to be unable to ensure the project performance due to the exposed numerous risks coming from the various and complex stake-holders, and its mega sizes. This paper proposes the method of risk performance index in order to improve an efficiency of performance measurement expanding to the risk view point from the existing integrated cost/schedule performance measurement. A risk performance index is compatible with the existing EVMS, and can make the performance measurement in 3 dimensions of the integrated cost/schedule/risk with 18 sub-indexes and variables.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.4 s.111
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• pp.11-21
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• 2005

The purpose of this study was to analyze and evaluate landscape characteristics by classification of landscapes in Chuncheon. A system was developed to convert images taken with a fish-eye lens to panoramic pictures. Landscape characteristics were analyzed by appearance rate and area distribution rate of landscape elements on panorama picture. Landscape characteristics were analyzed according to the number of times landscape elements appeared and the amount of area that each element occupied in the panoramic picture. Each panoramic picture was classified into five types based on these landscape element factors. Landscape evaluation was carried out using dynamic images converted from picture by fish-eye lens. The results of this study can be summarized as follows. The urban landscape can be characterized by four essential factors: interconnectedness, nature, urban centrality and landscape scale. Five types of landscapes were determined: detached residential building landscape (type 1), street landscape with various elements (type 2), street landscape in the center of a city (type 3), landscape of housing complex (type 4), and landscape of green space (type 5). Type 5 had the highest degree of landscape satisfaction and the landscape satisfaction increased with the number of appearances of natural elements. The amount of peen space had a high relation with a landscape satisfaction.

• Land and Housing Review
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• v.2 no.3
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• pp.259-268
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• 2011

Space extension and the increase of the number of households are helpful to raise business value of the remodeling through the renovation of apartment houses that is required by residents of new cities and large-scaled apartment. However, in the case of accepting this demand, it could have a bad influence on the landscape of a complex in terms of the structure of apartment houses and the safety of construction and urban planning, and a problem occurs in the aspect of fairness for reconstruction. For the study, the current status related to the remodeling system through laws, related articles since 2000 and research data was analyzed. In addition, the individual quantitative analysis was conducted in the four aspects to judge whether households expansion for remodeling is plausible:1) Statistical data to comprehend the changes of population and social structure 2) Survey data of floor space index and the building-to-land ratio of new cities at the intial stage for the review of the effect of architectural planning and urban environment 3) Surveys of experts on structural safety in order to judge whether the demand of expansion is accepted or not. 4) Quantitative analysis of each item to compare fairness with reconstruction. Therefore, this study is intended to understand problems of the remodeling system that is currently operated. Moreover, it will be further reviewed that the expansion of households is feasible through the permission of expansion and it will be discussed that the revitalization of the apartment remodeling has a positive impact on the residential environment.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.2
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• pp.32-41
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• 2001

The purpose of this study is to assess naturalness of each and use type for Daegu and provide the basic data for urban green space planning. The results are as follows: 1) As a result of periodic analysis, It is known that in the 1400´s that the rate of a-/oligo-/meso-hemeroby was over 90% of that area, in which naturalness was very high. By the 2020´s, the population will increase to about 3,500,000 and the occupation rae of meat-and poly-hemeroby, where naturalness is very low, is expected to increase rapidly. 2) The recent land uses of Daegu are divided ito 17 types. In the survey of a occupation rate of each land use type, a forest are occupies 48.8% of the entire area. The military installation zone is lowest with 0.07%. 3) Investigation of a dominant hemeroby grade in each land use type showed that the urban complex area in characterized by meta-hemeroby : and the space for pavement and building construction where naturalness is lowest. On the other hand, oligo-hemeroby that is worth being preserved was surveyed to be dominant in woodlands and natural forests. 4) In the analysis of hemeroby mapping in the process of a green space planning, it is clear that hemeroby will be used a s a tool that assesses the suitability for recreation activity of each sample case. For example, it enables a poly-hemeroby region to be utilized as a near-natural recreation area including $\beta$-and $\alpha$-euhemeroby region in Daegu. Besides, hemeroby can provide basic data to make a value judgement of each sample case with a view to preservation of nature.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.3
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• pp.74-90
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• 2010

The objectives of this paper are to introduce the GIS based resource circulation information, and to identify additional(or potential) industrial symbiosis based on existing industrial symbiosis and linkage-pair of industry by material. The resource circulation information contains information of the reuse of materials, water, and energy for all manufacturing companies in Ulsan Metropolitan City. The information can further be classified into the three steps -- input information(raw materials), flow information (products), and output information (by-products). The survey data from 3,768 industries and institutions in Ulsan Metropolitan area were collected and built into the GIS to analyze the mechanism of the industrial symbiosis. The results of this study strongly suggest that there are some additional industrial symbioses using by-products(materials, steam, waste water) and further efforts should be given to make them more effective. We expect that the methodology of building the resource circulation information of this study can be helpful to other local governments that try to build similar system.

• Journal of Radiation Protection and Research
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• v.32 no.1
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• pp.1-8
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• 2007

A model for radiological dose assessment in an urban environment, METRO-K has been developed. Characteristics of the model are as follows ; 1) mathematical structures are simple (i.e. simplified input parameters) and easy to understand due to get the results by analytical methods using experimental and empirical data, 2) complex urban environment can easily be made up using only 5 types of basic surfaces, 3) various remediation measures can be applied to different surfaces by evaluating the exposure doses contributing from each contamination surface. Exposure doses contributing from each contamination surface at a particular location of a receptor were evaluated using the data library of kerma values as a function of gamma energy and contamination surface. A kerma data library was prepared fur 7 representative types of Korean urban buildings by extending those data given for 4 representative types of European urban buildings. Initial input data are daily radionuclide concentration in air and precipitation, and fraction of chemical type. Final outputs are absorbed dose rate in air contributing from the basic surfaces as a function of time following a radionuclide deposition, and exposure dose rate contributing from various surfaces constituting the urban environment at a particular location of a receptor. As the result of a contaminative scenario for an apartment built-up area, exposure dose rates show a distinct difference for surrounding environment as well as locations of a receptor.

• Land and Housing Review
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• v.14 no.3
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• pp.93-106
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• 2023

This study attempted to simulate changes in the thermal environment according to the type of apartment complex in Korea using CFD techniques and evaluate the thermal environment by type of apartment. First, apartment complex types in the 2000s and 2010s were referred from previous studies and four types of apartment complex were extracted from. Second, the layout of the apartment complex and temperature changes were analyzed by the direction of wind inflow. Third, a standardized model was created from each type using tower type, plate type, and mixed driving. Last, CFD simulations were performed by setting up the inflow of wind from a total of eight directions. The temperature was relatively low in the type consisting of only the tower type and the type of placing the tower type in the center of the complex, regardless of the direction of the wind. It was due to the good inflow of wind from these types to the inside of the complex. It can be interpreted because wind flows easily into the complex in these types. The findings showed that wind flow and resulting temperature distribution patterns differed depending on the building type and complex layout type, confirming the need for careful consideration of the complex layout in the early design stage. The results are expected to be used as basic data for creating a sustainable residential environment in the early design stage of apartment complexes in the future.

• Advances in Computational Design
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• v.3 no.4
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• pp.319-338
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• 2018

High-performing architecture should be designed by taking into account the mutual dependency between the new building and the local context. The performative architecture plays an important role to avert any unforeseen failures after the building has been built; particularly ones related to the microclimate impacts that affect the human comfort. The use of the concept of solar envelopes helps designers to construct the developable mass of the building design considering the solar access and the site obstruction. However, the current analysis method using solar envelopes lack in terms of integrating the detailed information of the existing context during the simulation process. In architectural design, often the current site modelling not only absent in preserving the complex geometry but also information on the surface characteristics. Currently, the emerging applications of point clouds offer a great possibility to overcome these limitations, since they include the attribute information such as XYZ as the position information and RGB as the color information. This study particularly presents a comparative analysis between the manually built 3D models and the models generated from the point cloud data. The modelling comparisons focus on the relevant factors of solar radiation and a set of simulation to calculate the performance indicators regarding selected portions of the models. The experimental results emphasize an introduction of the design approach and the dataset visibility of the 3D existing environments. This paper ultimately aims at improving the current architectural decision of support environment means, by increasing the correspondence between the digital models for performance analysis and the real environments (context of design) during the conceptual design phase.