• Earthquakes and Structures
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• 제2권3호
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• pp.233-256
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• 2011

This paper investigates the applicability of newly developed Cu-Al-Mn shape memory alloy (SMA) bars to retrofitting of historical masonry constructions by performing quasi-static tests of half-scale brick walls subjected to cyclic out-of-plane flexure. Problems associated with conventional steel reinforcing bars lie in pinching, or degradation of stiffness and strength under cyclic loading, and in their inability to restrain residual deformations in structures during and after intense earthquakes. This paper attempts to resolve the problems by applying newly developed Cu-Al-Mn SMA bars, characterized by large recovery strain, low material cost, and high machinability, as partial replacements for steel bars. Three types of brick wall specimens, unreinforced, steel reinforced, and SMA reinforced specimens are prepared. The specimens are subjected to quasi-static cyclic loading up to rotation angle enough to cause yielding of reinforcing bars. Corresponding nonlinear finite element models are developed to simulate the experimental observations. It was found from the experimental and numerical results that both the steel reinforced and SMA reinforced specimens showed substantial increment in strength and ductility as compared to the unreinforced specimen. The steel reinforced specimen showed pinching and significant residual elongation in reinforcing bars while the SMA reinforced specimen did not. Both the experimental and numerical observations demonstrate the superiority of Cu-Al-Mn SMA bars to conventional steel reinforcing bars in retrofitting historical masonry constructions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2129_2131
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• 2009

Since Jan. 2004, the Ministry of Construction and Transportation has partly introduced estimation system of historical cost data in order to reflect result cost of construction market to cost estimation for public construction. It is expected that the purpose of the introduction would be evaluated considering the long-term development of domestic construction industry. In article 3, paragraph 4 of the planning criteria of estimated cost of financial regulation related to government contract rule, the profit estimated by historical cost data indicates sales profit and it is calculated by multiplying the sum of direct cost, indirect cost and general overhead by rate of profit. Finally, it is said that rate of profit cannot exceeds 10%. However, there are a lot of constructions for electronic equipment in the electronic construction and the proportion of government furnished material is very high, not like engineering works or constructions. Therefore, as the proportion of material cost over direct cost is relatively lower, if current rate of profit (10%) is applied, there would be a wide difference of cost in the items of profit under the estimation system of historical cost data. This paper was conducted to examine estimation methods of the items of profit under the estimation system of historical cost data and suggest reasonable applications.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 춘계학술대회 논문집 전기설비전문위원
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• pp.155-159
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• 2007

Since Jan. 2004, the Ministry of Construction and Transportation has partly introduced estimation system of historical cost data in order to reflect result cost of construction market to cost estimation for public construction. It is expected that the purpose of the introduction would be evaluated considering the long-term development of domestic construction industry. In article 3, paragraph 4 of the planning criteria of estimated cost of financial regulation related to government contract rule, the profit estimated by historical cost data indicates sales profit and it is calculated by multiplying the sum of direct cost, indirect cost and general overhead by rate of profit. Finally, it is said that rate of profit cannot exceeds 10%. However, there are a lot of constructions for electronic equipment in the electronic construction and the proportion of government furnished material is very high, not like engineering works or constructions. Therefore, as the proportion of material cost over direct cost is relatively lower if current rate of exceeds (10%) is applied, there would be a wide difference of cost in the items of profit under the estimation system of historical cost data. This paper was conducted to examine estimation methods of the items of profit under the estimation system of historical cost data and suggest reasonable applications.

• Wind and Structures
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• 제17권3호
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• pp.345-359
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• 2013

Turkey has been hosted various civilizations throughout centuries and it has become one of the oldest settlements all over the world due to the geographical location. Therefore, it has accommodated innumerable historical structures remain from the past civilizations. Protection and conservation of these historical constructions should be the major points for continuity of history. Crooked minaret is one of between these historical invaluable structures. It is located at the city of Aksaray and it dates back approximately 800 years. The minaret has lost its vertical position in time and bends on the North-West direction. In this study, general information is given about minarets and some restoration recommendations are given for crooked minaret based on performed some finite element structural analyses. These analyses are considered into three cases; 1-Dead loading, 2-Wind loading, and 3-Earthquake loadings. Results from the analyses are discussed detailed and some useful recommendations are given in the end of the study.

• 한국정보처리학회논문지
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• 제5권9호
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• pp.2281-2293
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• 1998

공간상의 지형객체는 토지의 소유주 변경이나 소유주의 신상 변경, 토지의 합병과 분할, 도로의 신설 및 변경에 따른 지형 변경 등과 같은 공간 또는 속성 변화에 의해 공간이력 데이터가 발생한다. 하지만 기존의 GIS(Geographic Information System)는 측정시점에서 지형객체의 스냅샷 정보만을 관리하므로 시간 흐름에 따른 공간이력을 유지할 수 없다. 따라서 이 연구는 공간 데이터베이스의 시간차원 확장을 통하여 시간과 공간을 동시에 지원하는 시공간 데이터베이스 모델과 이력 관리 체계를 설계하고 구현한다. 이 연구의 결과는 GIS 공간 데이터베이스의 시간차원 확장으로 지형객체의 모든 이력정보를 유지 관리할 수 있다.

• 건축역사연구
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• 제32권1호
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• pp.7-20
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• 2023

The construction method of scaffolding structures is different from Mortise and Tenon and bucket arch structure of traditional large woodwork. It forms an independent construction system-fixing nodes with knots, a large number of diagonal braces are used to fix shelves and the structures mostly contain X-shape and triangular shape details. Simple ones include stalls, sheds, rain sheds, altars, lamp racks etc. But the scaffolding with larger scale and more complicated structure are modeled on archways, theatres and other buildings which are used in commercial and festival activities. At present, Macao, Hong Kong, Guangdong, Sichuan, Shanxi and other places in China have retained the custom of using scaffolding structures in important festival activities, but their uses, techniques and building types are slightly different from place to place. Due to building and demolishing at any time, the construction and service cycle is short. As a result, there are almost no physical objects left. We can only deduce the use and technical characteristics of ancient scaffolding skills through the colorful building styles that have been preserved with folk activities in various parts of China, the craftsmanship handed down from generation to generation by the scaffolding guild and artisans, and the description of cultural and historical materials and the mutual corroboration of visual materials.

• Earthquakes and Structures
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• 제11권2호
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• pp.195-215
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• 2016

Rehabilitation of historical unreinforced masonry (URM) buildings is a priority in many parts of the world, since those buildings are a living part of history and a testament of human achievement of the era of their construction. Many of these buildings are still operational; comprising brittle materials with no reinforcements, with spatially distributed mass and stiffness, they are not encompassed by current seismic assessment procedures that have been developed for other structural types. To facilitate the difficult task of selecting a proper rehabilitation strategy - often restricted by international treaties for non-invasiveness and reversibility of the intervention - and given the practical requirements for the buildings' intended reuse, this paper presents a practical procedure for assessment of seismic demands of URM buildings - mainly historical constructions that lack a well-defined diaphragm action. A key ingredient of the method is approximation of the spatial shape of lateral translation, ${\Phi}$, that the building assumes when subjected to a uniform field of lateral acceleration. Using ${\Phi}$ as a 3-D shape function, the dynamic response of the system is evaluated, using the concepts of SDOF approximation of continuous systems. This enables determination of the envelope of the developed deformations and the tendency for deformation and damage localization throughout the examined building for a given design earthquake scenario. Deformation demands are specified in terms of relative drift ratios referring to the in-plane and the out-of-plane seismic response of the building's structural elements. Drift ratio demands are compared with drift capacities associated with predefined performance limits. The accuracy of the introduced procedure is evaluated through (a) comparison of the response profiles with those obtained from detailed time-history dynamic analysis using a suite of ten strong ground motion records, five of which with near-field characteristics, and (b) evaluation of the performance assessment results with observations reported in reconnaissance reports of the field performance of two neoclassical torsionally-sensitive historical buildings, located in Thessaloniki, Greece, which survived a major earthquake in the past.

• 건축역사연구
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• 제22권5호
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• pp.7-22
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• 2013

Gimlyong-sa temple has played an important role of Buddhist culture in Gyeongsangdo Provinces(嶺南地域) in the late Joseon Dynasty as the 31st head temple(本山) in the Japanese occupation. There are lots of architectural documentary records remained nevertheless, most of cultural heritages are destroyed by fire in 1997. There were 85 articles in five kinds of books which contained historical achievements of Gimlyong-sa temple and hermitages(Daeseongam(大成庵), Hwajangam(華藏庵), Yangjinam(養眞庵), Geum seondae(金仙臺), Dosoram(兜率庵), Myeongjeogam(明寂庵)). It is possible to understand the five situational peculiarities in the 17~19th century. At the first, they were compiled in 1914 to around 1930 by Kwon Sangro(權相老) to clarify the historical facts. Second, confirmed the formation process of the foundation narrative. Third, the meaning of Seolseondang(設禪堂), Manseru(萬歲樓) and Hyangnojeon(香爐殿) were recorded, it is possible to look at the concept of people at that time. Fourth, the great masters portraits were enshrined in hermitages, not in Gimlyong-sa temple. It means that a hermitage is not for only self-discipline or living but assembly of religious orders(門派). Fifth, Chimgye(枕溪), the great Buddhist clergy and carpenter of Gimlyong-sa, was nationwide active worker in 19th century because he was also in a charge of investment manager for construction.

• Earthquakes and Structures
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• 제11권4호
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• pp.563-582
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• 2016

The failure mechanism and maximum collapse load of masonry structures may change significantly under static and dynamic excitations depending on their internal arrangement and material properties. Hence, it is important to understand correctly the nonlinear behavior of masonry structures in order to adequately assess their safety and propose efficient strengthening measures, especially for historical constructions. The discrete element method (DEM) can play an important role in these studies. This paper discusses possible collapse mechanisms and provides a set of parametric analyses by considering the influence of material properties and cross section morphologies on the out of plane strength of masonry walls. Detailed modeling of masonry structures may affect their mechanical strength and displacement capacity. In particular, the structural behavior of stacked and rubble masonry walls, portal frames, simple combinations of masonry piers and arches, and a real structure is discussed using DEM. It is further demonstrated that this structural analysis tool allows obtaining excellent results in the description of the nonlinear behavior of masonry structures.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• 제1호
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• pp.176-182
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• 2001

The case for study in this paper is the Main Plan and Management for the Fukutoshin; the restructure of Nishi Shinjuku, This plan was first outlines in 1960, and includes a vast area of 96 ha for redevelopment. It aims to create a totally new center in the city. This was the first case in Japan, and in the world of a plan of these magnitudes. involving urban landscape restructuring from three points: Landscape (open spaces for public use: the Shinjuku Central Park and the surrounding area of the buildings), transport and commercial building developments. The Landscape plan for the green areas was decided in a way to compensate the population of the area and the visitors. As a rule, high-rise building constructions are placed each one in single lots and are surrounded by open spaces and greenery. Pedestrain areas are widened and also connected by bridges in a way to allow free circulation, and interconnection between the constructions and the green areas. Another important factor is the role that Private Corporation, and public interest plays. Joining these two forces has allowed the concretization of this project. This interpolation between public and private roles was an innovation in Japan, and it also the key for the concretion of the project. The historical review of the process and management of this project help us to put into perspective the introduction of new concepts and ideas, which were not related at that time to traditional Japanese Landscaping. Furthermore we are better able to understand the substantial increase in the percentage of land dedicated to green areas in contrast to the typical standards of Japanese cities.