• Journal of Energy Engineering
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• v.15 no.3 s.47
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• pp.174-180
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• 2006

The trend and outlook of energy supply and demand have an crucial effect on not only energy sector but also korean economy due to the rapid change of energy environments with continuous high oil price such as dubai crude oil price of above $60 a barrel. Specifically, korea is the 9th largest energy consuming nation in the world and the 97 percentages of energy import totally depends on the import of energy resources in korea. Korean economy is influenced directly by the trend and outlook of world energy on account of that. Moreover, Should korea be the annex 1 country having responsibility for reducing its greenhouse gas emissions to 1990 levels by the year 2000, in 2013, The effectuation of united nations framework convention on climate change will affect korean economy severely. In this study, we analyze the supply and demand of primary energy resources such as petroleum, coal, and natural gas. we then suggest the optimal alternatives of energy technology development that play an important part, which will be a temporary bridge, in going forward with hydrogen economy in the aspects of energy policy.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.4
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• pp.1-9
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• 2009

This paper investigates inelastic lateral-torsional buckling of stepped beams subjected to uniformly distributed load and end moments. A three-dimensional finite-element program ABAQUS (2007) and a regression program MINITAB(2006) were used to analytically develop new design equation for singly and doubly stepped beams with simple boundary condition. The flanges of the smaller cross-section in the stepped beams were fixed at 30.48 by 2.54 cm, whereas the width and thickness of the flanges of the larger cross-section varied. The web thickness and height of the beams were kept at 1.65 cm and 88.9 cm, respectively. The ratios of the flange thickness, flange width, and stepped length of beam are considered with analytical parameters. Two groups of 27 cases and 36 cases, respectively, were analyzed for doubly and singly stepped beams in the inelastic buckling range. The combined effects of residual stresses and geometrical imperfection on inelastic lateral-torsional buckling of beams are considered. The distributions of residual stress of the cross-section is same as shown in Pi and Trahair (1995) and the initial geometric imperfection of the beam is set by central displacement equal to 0.1% of the unbraced length of beam. The comparisons between results from proposed equations and the results from finite element analyses were presented in this paper. The maximum differences of two results are of 13% for the doubly stepped beam and 10% for the singly stepped beam. The proposed equations definitely improve current design methods for the inelastic lateral-torsional buckling problem and increase efficiency in building and bridge design.

• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.623-630
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• 2007

Grouting materials are used for the unification of superstructural and substructural body like bridge seat (shoe) or machinery pedestal and e.t.c by filling their intercalary voids. Accordingly, grouting materials have been developed and used mainly with products of high strength because those materials are constructed specially in a part receiving large or impact load. In this situation, the structural body constructed by grouting materials with high stiffness-centered (caused by high strength) products is apt to cause brittle failure when receiving over a limit stress and to cause cracks according to cumulative fatigue by continuous and cyclic load. In addition, grouting materials are apt to cause cracks by using too much rapid hardening agents that give rise to high heat of hydration to maintain high strength at early age. In this study, to overcome these problems, cement type grouting materials including powder of waste tire and resin as elastic materials which aim to be more stable construction and to be improvement of mother-body's unification are developed and endowed with properties of high toughness and high durability add to existing properties of high flowability, non-shrinkage and high strength. Besides, this study contribute to of for green construction materials for being possible recycling industrial waste like waste tire and flyash. On the whole, seven type mixing conditions are tested and investigated to choose the best mixing condition.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1295-1302
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• 2013

The structural deformed shape is important information to structural analysis. If the sufficient measuring points are secured at the structural monitoring system, reasonable and accurate structural deformation shapes can be obtained and structural analysis is possible using this deformation. However, the accurate estimation of the global structural shapes might be difficult if sufficient measuring points are not secure under cost limitations. In this study, SFSM-LS algorithm, the economic and effective estimation method for the structural deformation shapes with limited displacement measuring points is developed and suggested. In the suggested method, the global structural deformation shape is determined by the superposition of the pre-investigated structural deformed shapes obtained by preliminary FE analyses, with their optimum weight factors which lead minimization of the estimate errors. 2-span continuous bridge model is used to verify developed algorithm and parametric studies are performed. By the parametric studies, the characteristics of the estimation results obtained by the suggested method were investigated considering essential parameters such as pre-investigated structural shapes, locations and numbers of displacement measuring points. By quantitative comparison of estimation results with the conventional methods such as polynomial, Lagrange and spline interpolation, the applicability and accuracy of the suggested method was validated.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.5
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• pp.38-48
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• 2010

Adverse weather (e.g. strong winds, snow and ice) will probably appear as a more serious and frequent threat to road traffic than in clear climate. Another consequence of climate change with a natural disastrous on road traffic is respond to traffic accident more the large and high-rise bridge zone, tunnel zone, inclined plane zone and de-icing zone than any other zone, which in turn calls for continuous adaption of monitoring procedures. Accident mitigating measures against this accident category may consist of intense winter maintenance, the use of road weather information systems for data collection and early warnings, road surveillance and traffic control. While hazard from reduced road friction due to snow and ice may be eliminated by snow removal and de-icing measures, the effect of strong winds on road traffic are not easily avoided. The purpose of the study described here, was to design of amber information the relationship between traffic safety, weather, user information on road weather and driving conditions in local-scale Geographic. The most applications are the optimization of the amber information definition, improvements to road surveillance, road weather monitoring and improved accuracy of user information delivery. Also, statistics on wind gust, surface condition, vehicle category and other relevant parameters for wind induced accidents provide basis for traffic control, early warning policies and driver education for improved road safety at bad weather-exposed locations.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.2 s.54
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• pp.231-242
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• 2009

The baseline distribution of a structure represents the statistical distribution of dynamic response feature from the healthy state of the structure. Generally, damage-sensitive dynamic response feature of a structure manifest themselves near the tail of a baseline statistical distribution. In this regard, some researchers have paid attention to extreme value distribution for modeling the tail of a baseline distribution. However, few researches have been conducted to theoretically understand the extreme value distribution from a perspective of statistical damage assessment. This study investigates the asymptotic convergence of domain of attraction in extreme value distribution through parameter estimation, which is needed for reliable statistical damage assessment. In particular, the asymptotic convergence of a domain of attraction is quantified with respect to the sample size out of which each extreme value is extracted. The effect of the sample size on false positive alarms in statistical damage assessment is quantitatively investigated as well. The validity of the proposed method is demonstrated through numerically simulated acceleration data on a two span continuous truss bridge.

• Land and Housing Review
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• v.3 no.1
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• pp.59-68
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• 2012

The current land development cost price system is classified as the creating land by construction price and composition changes that occur sporadically in the process of completion at the source of the factors by incurred cost price. Housing for land cost price system is a lack of objectivity which scheme of the such a gap due to the land in accordance construction and incurred cost price system so far. Therefore, in order to increase the objectivity of costing the costing of predictable surprises should be reflected in the process. Under such a background, this study defined the effective differential ratio as the predictable, estimated them for various characteristics of each business district to reflect. For this, set the properties category of five types to attributes and making the complex category and Look-up table. Which result of model validation is showed a high reliability. Therefore, Continuous accumulation of material in the future, when them to reflect the construction cost, will contribute to the bridge the gap the construction cost between incurred them.

• Journal of KIISE:Databases
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• v.33 no.6
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• pp.578-589
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• 2006

Owing to the proliferation of Radio Frequency Identification (RFID) technologies which is being watched as a core technology of ubiquitous computing, applications which offer convenience to people using RFID technologies are more and more increased. To easily develop these applications, a middleware system which acts as a bridge between RFID hardware and application is essential. In this paper, we propose a novel XML-based RFID middleware system called UbiCore (Ubiquitous Core). UbiCore has following features: First, UbiCore employs its own query language called XQueryStream (XQuery for Stream Data) which is originated from XQuery. Second, UbiCore has the preprocessing phase called pre-filtering prior to query evaluation and reuses the intermediate result of previous evaluation to speed up the processing of RFID tag data stream. Third, UbiCore supports query on both continuously generated stream data and archived historical data. And last, UbiCore offers a distinct markup language called Context-driven Service Markup Language (CSML) to easily specify the linking information between context and service.

• Journal of the Korean Society for Library and Information Science
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• v.55 no.4
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• pp.245-266
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• 2021

In this study, in order to practice the social inclusion of libraries, the related policies currently announced in the 3rd Comprehensive Library Development Plan were examined, and the current status of tasks promoted by central administrative agencies and metropolitan and provincial libraries was examined based on these policies. As a result, first, in terms of active information welfare realization, various programs and services are being implemented to bridge the knowledge and information gap, but it seems that the scope of the target should be expanded in the future, cooperation with related organizations, and infrastructure improvement. Second, in terms of expanding the openness of the space, the expansion of the open space as an open space and the application of universal design are being performed. In the future, it seems that the scope of universal design application should be expanded in consideration of budget investment for continuous space reconstruction and diversity of users. Third, in terms of linking services across boundaries, services and programs are provided to infants and toddlers, children, women, the elderly, the underprivileged, job seekers, and multicultural families. In the future, it seems that the improvement of the service system for the expansion of inclusive services in libraries should precede, and cooperation between related ministries should be made to provide differentiated services. Finally, it is expected that future policy-making tasks for social inclusion should be considered not only for books, programs, and spaces, but also for librarians' education, establishment of cooperative networks with related organizations, and marketing for services and programs.

• Journal of Korea Port Economic Association
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• v.35 no.1
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• pp.139-162
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• 2019

In the case of Korea, policy support for shipping companies is limited, and the financial support should address the scale and period of support. Comprehensive measures are needed to boost the chances of reviving the industry. In order to secure competitiveness, the shipping companies need to make continuous efforts, prepare for the future by strengthening environmental regulations, and ensure that they have the ability to be flexible in their responses. The shipbuilding industry witnessed some improvement last year amid severe recession, but reforms are needed to address external and internal structural problems; further, to gain the characteristics of future leading industries, it is necessary to secure core technologies, as well as differentiated and specialized industrial competitiveness among rival countries through joint government intervention and joint R&D investment. Taking these steps will ensure that it has environment-friendly vessels and economic shipbuilding capabilities. The competitiveness of Busan Port should enable the utilization of the geopolitical characteristics of East Asia and contribute to: regional economic revitalization; development of its status as hub port; and securing the position of developed countries in East Asian logistics. For this purpose, it is necessary to establish a strategy to: expand the usability of shipowners/carriers; improve the quality of port operations; improve the portability of the smart system; expand the port of mega-ocean carriers; speed up port operations; and create low-cost ports. The establishment of a network of four countries will also require long-term global linkages. For example, there is a need to establish a logistics network between Eurasia and the European region, which will use the Russian Land Bridge System, as well as that of China.