• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.543-548
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• 2003

In this study, a numerical model is developed using axial deformation link elements that can effectively predict the failure behavior of RC type structures. Using this mod 1, numerical analysis was performed to investigate the strengthening effect and failure behavior of structures repaired with a new material. High-Performance Cementitious Composites, which is characterized by its ductility with 5% strain-capacity is used as a repair material. To investigate the validity of developed numerical model, simulations of direct tension specimen and flexural specimen are performed and the results are compared with published ones. The similar analysis is performed for RC beam. Through this study, it is seen that predicted response has a good agreement with the experimental results. Using this verified numerical model, the strengthening effect of repaired with HPCC structure is analyzed through load-displacement curve and failure modes. Also, the same numerical analysis is performed in RC beam repaired with HPCC. The effect of HPCC ductility is estimated for the overall behavior of structures. Based on the results, the fundamental data are suggested for repaired structures with HPCC.

• Steel and Composite Structures
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• v.46 no.6
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• pp.793-804
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• 2023

In this study, cyclic loading tests were conducted to assess the seismic performance of cast-in-place (CIP) concrete-filled hollow core precast concrete columns (HPCC) constructed using steel ducts and rubber tubes. The outer shells of HPCC, with a hollow ratio of 47%, were fabricated using steel ducts and rubber tubes, respectively. Two combinations of shear studs & long threaded bars or cross-deformed bars & V-ties were employed to ensure the structural integrity of the old concrete (outer shell) and new CIP concrete. Up to a drift ratio of 3.8%, the hysteresis loop, yielding stiffness, dissipated energy, and equivalent damping ratio of the HPCC specimens were largely comparable to those of the solid columns. Besides the similarities in cyclic load-displacement responses, the strain history of the longitudinal bars and the transverse confinement of the three specimens also exhibited similar patterns. The measured maximum moment exceeded the predicted moment according to ACI 318 by more than 1.03 times. However, the load reduction of the HPCC specimen after reaching peak strength was marginally greater than that of the solid specimen. The energy dissipation and equivalent damping ratios of the HPCC specimens were 20% and 25% lower than those of the solid specimen, respectively. Taking into account the overall results, the structural behavior of HPCC specimens fabricated using steel ducts and rubber tubes is deemed comparable to that of solid columns. Furthermore, it was confirmed that the two combinations for securing structural integrity functioned as expected, and that rubber air-tubes can be effectively used to create well-shaped hollow sections.

• Journal of Korea Technology Innovation Society
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• v.1 no.3
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• pp.402-418
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• 1998

This study attempts to analysis of the 1'ole and B/C(Benefict/Cost)of National Supported Supercomputing Center in process of the promotion for informatization in Korea. ETRI Supercomputing Center, as National Supported Supercomputing Center, was established in 1967 as a laboratory of KIST(Korea Institute of Science and Technology). ETRI Supercomputer Center have acted a leading role as National HPCC(High Performance Computing and Communication) in Korea. The result of B/C analysis of En Supercomputer Center showed that it is twenty times benefit as many as cost for the last 30 years. As soon as possible, it was Suggested that ETRI Supercomputer Center must be developed as National Supercomputing Center(NSC).

• 한국전산유체공학회:학술대회논문집
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• 2006.05a
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• pp.389-390
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• 2006

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.12
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• pp.46-51
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• 2003

슈퍼컴퓨팅인프라구축사업의 필요성은 슈퍼컴퓨터가 엄밀한 정확도를 요구하는 초미세 반도체 설계, 신물질 설계 및 항공우주 산업분야로부터 거대한 기상정보 예측 등 다양한 첨단과학 분야의 연구개발에 필수 장비라는 사실에서 비롯된다. 세계 각국은 슈퍼컴퓨터를 과학기술 발전과 국가 경쟁력 확보의 전략요소로 인식하여, 슈퍼컴퓨팅, 네트워킹, 첨단 응용 및 가시화장비 등을 상호 연계한 국가(또는 지역별) 슈퍼컴퓨팅 인프라 구축을 강화하고 있다. 미국은 1990년 초부터 HPCC (고성능 컴퓨팅 및 통신) 프로그램에 매년 10억불 규모의 예산을 지속적으로 투자하여 왔다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.4
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• pp.447-454
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• 1998

The recent rapid evolution of the Internet and the increasing interest on the electronic commerce had been driven by the United States Federal Governments as strategic areas. The real meaning and effect of these technological evolution should be understood to find our right direction in current hard IMF environment wisely by analyzing the continual R&D efforts and policies of the US Federal Governments in the Information and Telecommunication areas. The typical R&D projects were the Supercomputer center program launched at 1985, HPCC program at 1992, NII project at 1993, and CIC R&D program at 1996 which were increasing in scale and budget. This paper will explain the overall key R&D efforts and policies of US Federal Governments in the industrial, science and technologies, and Information and Telecommunications areas as well as the background, concepts, and effect of 1996 Telecommunication Act as a deregulation efforts.

• Electronics and Telecommunications Trends
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• v.11 no.4 s.42
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• pp.133-150
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• 1996

미국의 클린턴 행정부는 풍부한 영상 소프트웨어, 정보통신기술에서의 우위성, 고도의 네트워크를 바탕으로 21세기 정보사회에서의 주도권을 확보하기 위하여 노력하고 있다. 특히 냉전체제의 종식으로 인하여 국방분야에서의 여력이 생긴 연구개발 자원을 민생기술중심으로 전환하고 있으며, 국방분야에서 축적된 기술을 민간으로 확산하는 Spin-off 패러다임이 비판을 받으면서 Spin-on 패러다임을 동시에 구사하는 Dual-use전략을 사용하고 있다. 특히 NII구축을 통하여 다음 세기에서의 국가경쟁력을 강화하고, 국민의 삶을 질을 높이기 위한 노력을 선두적으로 추구하고 있는 상황임을 감안할 때, 미국에서의 정보통신기술정책 및 전략방향을 살펴보는 것은 초고속 기반구축사업을 추진하고 있는 우리 실정에 시사되는 바가 크리라 판단된다. 이를 위해서 미국의 정보통신기술 개발체계와 HPCC(High Performance Cumputing and Communications) 프로그램의 기술개발 현황을 중심으로 정보통신기술개발 동향을 분석하고 정보통신기술에 대한 장기적인 연구개발 방향을 분석하고자 한다.

• Journal of Platform Technology
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• v.8 no.2
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• pp.3-9
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• 2020

Big Data is a new concept in the global and local area. This field has gained tremendous momentum in the recent years and has attracted attention of several researchers. Big Data is a data analysis methodology enabled by recent advances in information and communications technology. However, big data analysis requires a huge amount of computing resources making adoption costs of big data technology. Therefore, it is not affordable for many small and medium enterprises. We survey the concepts and characteristics of Big Data along with a number of tools like HADOOP, HPCC for managing Big Data. It also presents an overview of big data like Characteristics of Big data, big data technology, big data management tools etc. We have also highlighted on some challenges and opportunities related to the fields of big data.

• Journal of the Korea Concrete Institute
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• v.20 no.3
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• pp.335-343
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• 2008

In order to improve the workability in erecting Precast Concrete (PC) members and enhance the seismic resistance capacity of the joints in PC moment frames, a new PC column and its construction process are introduced in this paper. This column is manufactured by centrifugal force in keeping the hollow tube inside; the hollow is little bit wide and the grout can be poured from top to bottom after erection at site so that more compact grouting is possible in horizontal joint. The repeated cyclic loading test for four full scaled specimens was conducted to evaluate the seismic resistance capacity of the joint designed by the proposed system. For the continuity of main reinforcements in column, two connecting methods are used in designing specimens; one is to use mechanical connector and other is lab splice. From the cyclic lateral loading test, it was found that the seismic capacity of the developed PC column joint is comparable to that of monolithic joint.