• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.125-132
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• 1998

경량골재 콘크리트의 내구성과 경제성에 대한 인식 부족으로 조경재료나 인공토양 둥 구조부재 이외의 분야에 사용되고 있는 국내 실정에 비해서, 구미 여러나라에서는 고강도 경량골재를 장지간 교량과 고충건물에 사용하고 있다. 경량골재 콘크리트는 구조물의 재료비 단순비교에 있어서도 경제성이 있을 뿐만 아니라, 자중감소로 인한 구조적, 기하학적 장점도 있으며, 또한 고강도 경량골재의 개발로 경량골재가 가지고 있는 여러 문제점을 해소하여 사용성과 내구성에 있어서 보통골재 콘크리트와 큰 차이가 없는 상황이다. 그러나국내에서 생산된 경량골재는 닫힌 공극보다 열린 공극을 많이 내포하고 있어 수분흡수가 많고, 특히, 동결융해에 대한 내구성에 취약한 문제점을 가지고 있다. 본 논문에서는 내동해성 향상을 위해 10종류의 고강도 경량골재 콘크리트 공시체를 제작하여 실리카 흄, 물.시멘트비, AE제, 강섬유 등을 실험 변수로 하여동결융해 실험을 수행하였다. 연구결과 실리카흄, 물.시멘트 비는 어느 정도 내동해성을 향상시키지만 근본적인 해결방안이 되지 못하며, AE제를 첨가한 공시체와 강섬유를 사용한 공시체는 동결융해 내구성 지수가 90%이상으로 측정되어 내동해성을 개선시킬 수 있는 요소로 나타났다.

• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.178-186
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• 2018

Subject classification of thesis units is essential to serve scholarly information deliverables. However, to date, there is a journal-based topic classification, and there are not many article-level subject classification services. In the case of academic papers among domestic works, subject classification can be a more important information because it can cover a larger area of service and can provide service by setting a range. However, the problem of classifying themes by field requires the hands of experts in various fields, and various methods of verification are needed to increase accuracy. In this paper, we try to classify topics using the unsupervised learning algorithm to find the correct answer in the unknown state and compare the results of the subject classification algorithms using the coherence and perplexity. The unsupervised learning algorithms are a well-known Hierarchical Dirichlet Process (HDP), Latent Dirichlet Allocation (LDA) and Latent Semantic Indexing (LSI) algorithm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.19-25
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• 2016

Engineering structures including civil infrastructures require a life-cycle cost and benefit during their service lives. The service life of a structure can be extended through appropriate inspection and maintenance actions. In general, this service life extension requires more life-cycle cost and cumulative benefit. For this reason, structure managers need to make a rational decision regarding the service life management considering both the cost and benefit simultaneously. In this paper, the probabilistic decision tool to determine the optimal service life based on cost-benefit analysis is presented. This decision tool requires an estimation of the time-dependent effective cost-benefit under uncertainty to formulate the optimization problem. The effective cost-benefit is expressed by the difference between the cumulative benefit and life-cycle cost of a deteriorating structure over time. The objective of the optimization problem is maximizing the effective cost-benefit, and the associated solutions are the optimal service life and maintenance interventions. The decision tool presented in this paper can be applied to any deteriorating engineering structure.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.2
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• pp.181-192
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• 2008

A Web-based design automation system for concrete slab bridge has been developed to manage the resultant documents as well as to speed up the repetitive design process. Manipulation of engineering drawings in the Web page is one of the critical functions needed for Web-based design automation. Active Server Pages (ASP) is used to that collects design parameters in the database, and eXtensible Markup Language (XML) and XML-based vector graphics are expected to facilitate the representation of engineering drawings in the Web page. In this paper, we present how we used XML and Scalable Vector Graphics (SVG) to compose engineering drawings and represent them in the Web page. XML Data Island we designed to define drawing components turned out effective in manipulating the engineering drawings in the Web page.

• Journal of Energy Engineering
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• v.29 no.1
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• pp.25-33
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• 2020

Recently, as the mandatory policy of zero energy building is promoted, policies / systems for transition to Zero Energy School are being promoted, but there is no method to systematically analyze and verify the results of energy saving activities for school buildings. For the study of energy performance verification methodology, the current status of related standards was referred to, and the case study of other methodologies was conducted to examine the tools that can analyze the performance in the field. In addition, this study analyzed the current status and characteristics of energy management through domestic school visits. In this paper, we presented various energy saving projects such as air conditioning and heating facilities, lighting, insulation, change operation behavior, and improve operation methods in new and existing school buildings, and M & V methods for verifying energy savings before and after implementation of energy conservation projects.

• Journal of the Korean Society for information Management
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• v.24 no.1 s.63
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• pp.301-319
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• 2007

Nowadays the information environment enables users to access the traditional library collection as well as various digital information resources. In this rapidly changing environment, the use of digital information resources such as web sites, data, and homepages has increased. In this research, highly-cited authors' research outcomes as well as the research outcomes of the people, who cited the highly-cited authors' works, were extracted then compared with information stored in the medical colleges' digital libraries and the academic information portals in the clinical medicine area by using the citation information provided by Essential Science Indicators from ISI Web of knowledge. Out of 10,000 authors,146 people's homepages, which present research outcomes, were analyzed. The research outcomes listed in the homepages included journal papers, monographs, conference proceedings, and lecture notes. About 15% of the journal papers, 32% of the monographs, 48% of the conference proceedings, and 100% of lecture notes were accessible only through the homepages. The research outcomes accessible from the homepages were almost analogous to the ones available through the medical college's digital libraries and the academic information portals. Therefore, the digital library collection will be improved and expanded quantitatively and qualitatively by collecting and using the information in the homepages of the prestigious researchers.

• Journal of Korean Society of Steel Construction
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• v.18 no.4
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• pp.481-490
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• 2006

The actual performance of a building during an earthquake depends on many factors. The prediction of the seismic performance of a new or existing structure is complex, due not only to the large number of factors that need to be considered and the complexity of the seismic response, but also due to the large inherent uncertainties and randomness associated with making these predictions. A central issue of this research is the proper treatment and incorporation of these uncertainties and randomness in the evaluation of structural capacity and response has been adopted in the seismic performance evaluation of steel tall buildings to account for the uncertainties and randomness in seismic demand and capacities in a consistent manner. The basic framework for reliability-based seismic performance evaluation and the key factors for statistical studies were summarized. A total of 36 target structures that represent typical tall steel buildings based on national building code (KBC-2005) were designed for the statistical studies of demand factor s and capacity factors. The incremental dynamic analysis (IDA) approach was examined through the simple steel moment frame building in determination of global drift capacity.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.415-417
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• 2017

국내의 도시화와 중국에서 넘어오는 오염물질에 의하여 대기오염에 대한 피해가 갈수록 커져가고 있다. 하지만 대기오염 집중측정소 6곳에서만 초미세먼지의 구성 성분을 실시간으로 측정하고 있고 그에 대한 자료를 공개하지 않는 것으로 알려져 있다 [1]. 또한 정부는 서비스 개발 및 제공 과정에서 공공성에 대한 고려도 중요하지만, 그것이 얼마나 시민들의 수요나 관심과 결부되어 있는지에 대한 고민도 함께 요구된다. 특히 서울특별시와 같이 대도시에서 거주하는 시민들의 주된 관심사 중 대기오염과 관련한 관심은 지속적으로 높아지고 있다 [2]. 본 논문은 6가지의 센서가 내장된 LED 조형물을 실생활 공간에 배치하고 조형물, 모바일, 웹에서 정보를 실시간으로 제공하는 대기오염 정보 제공 시스템을 제안할 것이다. 일반 대기 측정소와 다른 LED 조형물을 통하여 시민들의 접근성과 편리함을 향상시킬 수 있는 새로운 방식의 대기오염 정보 제공 시스템을 기대해볼 수 있을 것으로 예상된다.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1547-1549
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• 2003

송배전용 설비에 사용되는 옥외 절연물로는 자기질이나 유리질의 애자가 주로 사용되어 왔지만 최근 신소재의 발달로 가볍고 절연성능이 우수한 폴리머 애자가 보편화되기 시작하였다. 폴리머 애자가 자기질 및 유리질의 애자에 비하여 내열성과 내후성이 부족한 것은 사실이지만 절연물이 오염과 습윤된 환경에서 폴리머 애자의 절연성능이 휠씬 우수한 것으로 밝혀지고 있다. 폴리머 애자의 장기성능 예측을 위하여 많은 수단과 측정방법이 연구되어 왔다. 폴리머 애자의 하우징 재료는 내열성, 내후성, 산화안정성, 발수성 및 내오염성 등 절연소재로서 우수한 특성을 가지고 있지만 하우징 표면에서의 방전이 발생될 때 옥외절연물에서의 성능은 하우징 재료의 배합처방에 따라서 많은 차이가 나고 있다. 본 논문에서는 하우징용 소재의 특성을 평가하기 위한 평가방법과 평가결과를 해석하는 기술에 대하여 기술하였다.

• Fire Science and Engineering
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• v.30 no.4
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• pp.141-147
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• 2016

The fire fighting and safety research development program supported by Ministry of Public Safety and Security is composed of fire prevention and alert technology research, special disaster response technology research, and rescue and disaster-field response safety technology research. The principal accomplishment indices of this research program are (1) patent submitting or registration; (2) field test, ensuring performance criteria for commercialization, development of prototype, registration of software, royalty of technology-transfer; (3) the task to be carried out in a published research paper, and number of applied policies; and (4) the study period of task performance of employment and incubated high-technology manpower. Therefore, this study analyzed the performance result of a patent, research paper, and software registration of the fire-fighting and safety R&D program supported by Ministry of Public Safety and Security from 2012 to 2014.