• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.1-8
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• 2003

In locations where the cost of concrete is relatively high or in situations where the weight of concrete members has to be kept to a minimum, it may be more economical to use hollow reinforced concrete vertic al members. Hollow reinforced concrete colun-ms with a low axial load, a moderate longitudinal steel percentage and a reasonably thick wall were found to perform in a ductile manner at the flexural strength, similar to solid columns. Hollow reinforced concrete columns with a high axial load, a high longitudinal steel percentage, and a thin wall were found, however, to behave in a brittle manner at the flexural strength, since the neutral axis is forced to occur away from the inside face of the tube towards the section centroid and, as a result, crushing of concrete occurs near the unconfined inside face of the section. If, however, a steel tube is placed near the inside face of a circular hollow column, the column can be expected not to fail in a brittle manner through the disintegration of the concrete in the compression zone. A design recommendation and example through the moment-curvature analysis program for curvature ductility are herein presented. A theoretical moment-curvature analysis for reinforced concrete columns, indicating the available flexural strength and ductility, can be conducted, providing that the stress-strain relation for the concrete and steel are known. In this paper, a unified stress-stain model for confined concrete by Mander is developed foi members with circular sections.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2006.05a
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• pp.211-216
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• 2006

교통주제도는 건설교통부와 한국교통연구원이 ${\ulcorner}$국가교통DB구축사업${\lrcorner}$의 일환으로 제작한 것으로, 국토지리정보원의 NGIS 수치지도(축척 1:5,000)를 기반으로 하여 현장조사 및 문헌조사를 통해 갱신, 보완하여 교통 분야의 활용에 적합하도록 구축한 GIS 수치지도이다. 교통주제도는 현장조사와 문헌조사를 통해 수집된 자료를 기반으로 구축되며 이중 교통시설물조사는 문헌자료(준공도로현황 등)를 참고하여 산정된 조사대상에 대하여 GPS 조사시스템을 활용, 도형 및 속성정보를 취득하는 것을 말한다. 조사항목은 도형정보(노드, 링크) 및 속성정보(차선수, 도로번호 등)이며 GPS 조사시스템과 조사원장(도면)을 이용하여 조사한다. 교통시설물조사와 문헌자료조사를 통해 수집된 자료는 단위도엽(1:5,000기준)별로 교통주제도에 반영되며 최종적으로 전국단위의 통합자료로 구축된다 교통주제도는 사용목적과 축척기준에 따라 단순화되며 이를 교통주제도 레벨이라 한다. 교통주제도의 레벨은 총 4단계로 구분되며 현재 레벨2에서 레벨4까지 구축되고 있다. 교통분석용 네트워크는 교통시설투자계획, 수요분석, 타당성 평가와 같은 교통분야의 연구를 수행하기 위해 반드시 필요한 자료이다. 교통분석용 네트워크는 교통주제도보다 더 단순화된 도로망 모델로서 구성요소는 노드(시점, 종점, 죤 센트로이드)와 링크(도로망, 센트로이드 커넥터)이며 도로의 기하구조보다는 논리적 구조(방향성, 노드/링크 연결성 등)에 중점을 둔 데이터이다 교통분석용 네트워크는 교통주제도의 도형과 속성정보를 기반으로 하며 각종 통계자료(도로교통량통계연보 등)를 활용, 구축된다. 교통분석용 네트워크는 구축시점에 따라 현재 및 장래 네트워크로 구분되며 장래 네트워크는 기준년도부터 2031년까지 5년 단위로 계획된 장래도로를 반영하여 구축된다. 교통주제도 및 교통분석용 네트워크는 국가교통DB구축사업을 통해 구축된 자료로서 교통체계효율화법 제9조의4에 따라 공공기관이 교통정책 및 계획수립 등에 활용할 수 있도록 제공하고 있다. 건설교통부의 승인절차를 거쳐 제공하며 활용 후에는 갱신자료 및 활용결과를 통보하는 과정을 거치도록 되어있다. 교통주제도는 국가의 교통정책결정과 관련분야의 기초자료로서 다양하게 활용되고 있으며, 특히 ITS 노드/링크 기본지도로 활용되는 등 교통 분야의 중요한 지리정보로서 구축되고 있다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.12A
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• pp.2000-2011
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• 2001

In this Paper, we convert conventional low speed(1x, 6x) DVD systems designed by analog PLL(Phase Locked Loop) into digital PLL to operate at high speed systems flexibly, and present optimal DPLL model in high speed(20x) DVD systems. Especially, we focused on the design of DPLL that can overcome channel effects such as bulk delay, sampling clock frequency offset and asymmetry phenomenon in high speed DVD systems. First, the modified Early-Late timing error detector as digital timing recovery scheme is proposed. And the four-sampled compensation algorithm using zero crossing point as asymmetry compensator is designed to achieve high speed operation and strong reliability. We show that the proposed timing recovery algorithm provides enhanced performances in jitter valiance and SNR margin by 4 times and 3dB respectively. Also, the new four-sampled zero crossing asymmetry compensation algorithm provides 34% improvement of jitter performance, 50% reduction of compensation time and 2.0dB gain of SNR compared with other algorithms. Finally, the proposed systems combined with asymmetry compensator and DPLL are shown to provide improved performance of about 0.4dB, 2dB over the existing schemes by BER evaluation.

• Korean Journal of Social Welfare
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• v.67 no.3
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• pp.253-280
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• 2015

This study reconsiders the concept of publicness by raising a question about the problems which the recent marketization of social services in South Korea. The existing perspective on publicness, however, is insufficient to account for the entire Long-term care market because only public organizations have publicness. Accordingly, this study presents 'integrated publicness', particularly 'dimensional publicness' and 'normative publicness'. A disproportional stratified sampling procedure was used to consider ownership. A merged dataset combining surveys from 248 Long-term Care facilities and on-line resources was used and analyzed by multiple regression, negative binomial regression and multiple imputation analysis. The analysis results suggest as follows. First, ownership publicness appeared more effective in the overall. Second, the regulations on the government funding did not show effective, and the regulation on evaluation system showed the effect. Third, professionalization of normative publicness showed a negative effect on service structure and showed a positive effect on service process. Lastly, user of free services whose public accountability was identified to be effective on service structure and outcome. These findings suggest that not only existing ownership but also dimensional publicness and normative publicness showed an effect on service quality. In this respect, this is important as the performance produced by empirical models of integrated publicness, in this situation that the outcome of marketization is insignificant.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.1-18
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• 2009

A series of three-dimensional numerical simulations using a generalized multidimensional hydrodynamic dispersion numerical model is performed to simulate effectively and to evaluate quantitatively impacts of urbanization on density-dependent groundwater flow and salt transport in a coastal aquifer system, Suyeong-Gu, Busan, Korea. A series of steady-state numerical simulations of groundwater flow and salt transport before urbanization with material properties of geologic formations, which are established by numerical modeling calibrations considering all the urbanization factors, is performed first without considering all the urbanization factors. A series of transient-state numerical simulations of groundwater flow and salt transport after urbanization is then performed considering the urbanization factors individually and all together. Finally, the results of both numerical simulations are compared with each other and analyzed. The results of the numerical simulations show that density-dependent groundwater flow, salt transport, and seawater intrusion in the coastal aquifer system are intensively and extensively impacted by the urbanization factors. Especially, these urbanization factors result in the changes of the total groundwater volume and salt mass in the coastal aquifer system. However, such impacts of each urbanization factor are not spatially uniform but locally different.

• The Journal of the Korea Contents Association
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• v.11 no.10
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• pp.257-266
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• 2011

The establishment of Culture Technology Institute is now under discussion. In case of advanced countries (including USA, Japan and EU) practices market-oriented policies in the area of culture and entertainment industry. Therefore it is hard to find out Government-funded Institute which Korea could benchmark. In this situation, there are many different opinions about its organizational structure, size of organization and budget, and when the institute should be established. This study proposed a Consolidated-Decentralized model as a proper organizational structure after evaluating 4 different models based on 4 criterion. And based on results produced by the model developed for our research, this study suggested proposals that the number of research personnel and the size of budget should be larger than 300 persons and 1200 billion won respectively. However, the establishment of institute should be decided by not only economic factor but also various factors such as political element, externality, private company investment and effect on production inducement etc. If new institute focused on different area from ETRI, then the time and size of the institute could be decided by the result of policy analysis.

• The KIPS Transactions:PartD
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• v.12D no.7 s.103
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• pp.1049-1064
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• 2005

The demands of increasingly complicated software have led to the proliferation of object-oriented design methodologies in embedded systems. To execute a system designed with objects in target hardware, a task set should be derived from the objects, representing how many tasks reside in the system and which task processes which event arriving at an object. The derived task set greatly influences the responsiveness of the system. Nevertheless, it is very difficult to derive an optimal task set due to the discrepancy between objects and tasks. Therefore, the common method currently used by developers is to repetitively try various task sets. This paper proposes Scenario-based Implementation Synthesis Architecture (SISA) to solve this problem. SISA encompasses a method for deriving a task set from a system designed with objects as well as its supporting development tools and run-time system architecture. A system designed with SISA not only consists of the smallest possible number of tasks, but also guarantees that the response time for each event in the system is minimized. We have fully implemented SISA by extending the ResoRT development tool and applied it to an existing industrial PBX system. The experimental results show that maximum response times were reduced $30.3\%$ on average compared to when the task set was derived by the best known existing methods.

• Information Systems Review
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• v.4 no.2
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• pp.191-208
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• 2002

In the area of new millennium of twenty first century, one of the urgent and critical research issues in commerce area is the regenerating of new business opportunities from the high value added perspectives. With this motivation, in this paper, we create new on-line e-businesses with the speed of lightning their affiliated supply, finance and business communities - which are involved in more and more tightly connected, open trading - we find that we need to deal with hundreds of business collaborative partners, millions of buyers and sellers while we have to face incompatible IT systems. Challenges of new business opportunities linking multi-enterprise data and processes cost effectively, reliably and securely in real time remains an open area in e-business. This challenge we shall describe as the problem of synchronization of multiple enterprise collaborative e-business opportunities (production related), value (finance related), business (operations related) in new business opportunity and infrastructure integrated all together over the off-line and online basis. It brings a new e-commerce opportunities infrastructure into this profitable challenge: by extracting and tracking new business information, new trends in the events of e-business processes. The transformation of the traditional commerce into this type of electronic based commerce can be interpreted as new Cultural Revolution. The revolution will be a new paradigm crossing over the geographical, and organizational zone, restructuring enterprise business process infrastructure.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.199-207
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• 2006

Recent global warming seems to be dramatic and has influenced forest ecosystems. Changes in phonology of biota, species distribution range shift and catastrophic climatic disasters due to recent global warming have been observed during the last century. Korean forests located mainly in the temperate zone also have been experienced climatic change impacts including shifting of leafing and flowering phonology, changes in natural disasters and forest productivity, However, little research has been conducted on the impact of climate change on forest ecosystems in Korea which is essential to assess the impact and extent of adaptation. Also there is a shortage in basic long-term data of forest ecosystem processes. Careful data collection and ecological process modeling should be focused on characteristic Korean forest ecosystems which are largely complex terrain that might have hindered research activities. An integrative ecosystem study which covers forest dynamics, biological diversity, water and carbon flux and cycles in a forest ecosystem and spatial and temporal dynamics modeling is introduced. Global warming effects on Korean forest ecosystems are reviewed. Forestry activity and the importance of forest ecosystems as a dynamic carbon reservoir are discussed. Forest management options and challenges for future research, impact assessment, and preparation of mitigating measures in Korea are proposed.

• Archives of design research
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• v.11 no.1
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• pp.173-184
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• 1998

This study deals with the visual quality in the future urban landscape and architectural environment, and as such, aims to identify a scientific and objective aesthetic and visual quality from the perspective of empirical aesthetics. The empirical aesthetics provides a framework that can be utilized in understanding human perception, consciousness, and behavior and a way to categorize the visual quality and to explain and predict its effect. The study examines various theories on environmental perception, cognition, and some new approaches to environmental aesthetics, and tries to present aesthetic properties that can be applied to environmental design. First, the aesthetic experience in visual perception can be defined as a combined effect of psychobiological properties and human activity, i.e. an interaction between the formal and symbolic signs in environment and the conceptual framework of man. The effect of visual quality differs and varies a great deal, depending on the sociocultural, personal and collective value system, so it is hard to define it in absolute terms. Second, the impact of visual quality and its aesthetic effect has to do with pleasure, preference, the aptitude for survival, and self regulation. Third, aesthetics is one of the areas that can benefit a great deal from an interdisciplinary approach. and an empirical study such as this can be used as a basis for design, planning, and evaluation.