• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.4
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• pp.99-106
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• 2012

This study presents estimation method of temperature-dependent thermal conductivity by using solution of inverse heat conduction problem. Time and depth temperature distribution data from full-scale fire test were used for estimating temperature-dependent thermal conductivity on hybrid-fiber reinforced shield tunnel lining. At short heating time, estimated thermal conductivity sharply decreased within $100^{\circ}C$. On the other hand, it reflected thermal properties of concrete and effect of steel fiber at heating time of measured maximum heating temperature. Thus arbitrary time should be determined to estimate temperature-dependent thermal conductivity in time zone of measured maximum heating temperature. Estimated temperature-dependent thermal conductivity is similar to results of other study.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.6
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• pp.1-10
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• 2014

In this study, thirteen reinforced concrete beams, ground granulated blast furnace slag, replacing recycled coarse aggregate with PVA fiber (BSPG series) and recycled coarse aggregate with hybrid fiber ($BSPGR_1$, $BSPGR_2$ series), and standard specimen (BSS) were constructed and tested under monotonic loading. Experimental programs were carried out to improve and evaluate the Structural performance of such test specimens, such as the load-displacement, the failure mode, and the maximum load carrying capacity. All the specimens were modeled in 1/2 scale-down size. Test results showed that test specimens ($BSPGR_1$, $BSPGR_2$ series) was increased the compressive strength by 13%, the maximum load carrying capacity by 4~21% and the ductility capacity by 4~28% in comparison with the standard specimen (BSS). And the specimens ($BSPGR_1$, $BSPGR_2$ series) showed enough ductile behavior and stable flexural failure.

• Journal of Korean Society of Archives and Records Management
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• v.3 no.1
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• pp.111-127
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• 2003

Web-based information resources should be managed and used methodically in the same manner as the paper-based resources are managed and used. It is necessitated by the prevalence of web-based delivery of a variety of information. To develop a web-based digital collection, it is critical to establish a set of standardized evaluation criteria for web-resources. The evaluation criteria needs to include authority, trustworthy, reliability, functionality, relatedness, accessibility, structure, design, user support, and security related matters. However, it is also necessary to have certain flexibility to either emphasize or include particular evaluation criteria to reflect varying characteristics of the web resources especially for the purpose of developing an effective digital collection. In addition, it is essential to review the evaluation criteria with respect to value, demand, duplication prevention, and intellectual property, which are relevant to the web-based digital collection development. Finally, various strategies were suggested as means to develop more effective web-based digital resource collection. These strategies include organizing a selection committee to ensure the objectivity and consistency in web-resource evaluation; developing a model for web-based digital resource collection; sharing new standards, protocols, markups, and metadata with other digital libraries; and developing user-centered digital resource collection.

• Journal of Korean Society of Archives and Records Management
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• v.16 no.3
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• pp.1-30
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• 2016

A collection policy (or a collection development policy) is a document that archival institutions must have to allow them to build their collections legitimately and consistently. Digital archives often lack sustainable financial and systematic supports. Thus, it is especially important for digital archives to have a policy for consistent collection activities. Digital archives have a different set of characteristics from physical records, and these characteristics should be considered in a collection policy. This study was initiated to create such a policy for the No Gun Ri Digital Archive. It reviewed existing literature for collection policies in archives and digital archives. Moreover, it examined several cases of digital archives and their policies to identify the necessary elements as well as the legal and procedural coverages for digital content and services. Furthermore, it studied the unique characteristics of the No Gun Ri incident and the No Gun Ri Digital Archive. Based on such investigation, a collection policy for the No Gun Ri Digital Archive was suggested. It is believed that suggesting a practical collection policy will provide a useful precedent for future digital archive projects.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.135-142
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• 2013

With a rapid growth of hardware and product material industries, evolution of handheld terminal technologies is progressed. Various applications using mobile phone are the major trend in recent smart applications. Especially, interesting applications using camera module in a smartphone are developed continuously, mobile users are able to use various useful mobile applications nowadays. In this paper, we design and implement smartphone app for measuring real size of the shooting object in the image taken by a camera module in a smartphone precisely. We implement 4 different shooting modes for precise measurement of objects and 0 point control module is developed to minimize the differences of shooting images taken by different types and systems of various smartphones. The smartphone app proposed and implemented in this paper is analyzed and evaluated by a simulation study.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.1
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• pp.53-60
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• 2009

Isolated structures use devices such as high damping rubber bearings (HDRB) in order to dramatically reduce the seismic forces transmitted from the substructure to the superstructure. The laminated rubber bearing is the most important structural member of a seismic isolation system. The basic characteristics of rubber bearings have been confirmed through compression tests, compressive shearing tests and creep tests. This paper presents the results and analysis of a 1000hr, ongoing creep test conducted at 7.5MPa, 8.37MPa in our laboratory. The long-term behavior of bridge bearings, such as high-damping rubber bearings, will be discovered through a compression creep test subjected to actual environmental conditions. These tests indicated that the maximum creep deformation is about $0.3{\sim}1.92%$ of total rubber thickness.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.6
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• pp.55-65
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• 2010

The purpose of this experimental study is to evaluate the seismic performance of a 2 story RC shear wall system by the static reversal loading test. The lower 2 stories of the prototype structure were selected, and the specimens of this study were comprised of a T-type wall with an opening. The specimens were reduced to about 60% of the full scale size and were constructed to measure the result of the experimental variable regarding the existence of a lintel beam. To perform this study, the static repeated loading test was performed. According to the existence or absence of a lintel beam, the structural capacities and behavioral differences of the shear wall system were compared. The test results of this study showed that the specimen with a lintel beam underwent the seismic performance with an ultimate strength and ductility capacity better than the specimen without a lintel beam.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.6
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• pp.33-43
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• 2010

This paper deals with the hybrid structural test technique which has been introduced and studied currently in Korea. In this study, a Mini-MOST system which was developed as a part of NEES research was modified and improved to reduce the total simulation time to half of the original system. Using the proposed system together with the 2 dimensional small steel frame specimen, the validity and efficiency of the hybrid test technique is investigated. Even though the hybrid test has been developed as an alternative to the shaking table test and has been studied and applied for a long time in several countries, no attempt has been made to compare it directly with the shaking table test. Therefore, in this study, the hybrid test results are compared with those of the shaking table test as well as with a numerical simulation for the verification of hybrid test. From the comparison and analysis of the test results, it is concluded that the hybrid test can simulate the actual seismic behavior of structural systems very accurately and it can be a good alternative to the shaking table test.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.4
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• pp.647-657
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• 2017

The main purpose of this study is to investigate the static & dynamic behavior of a precast bracket under precast road deck slab of double deck tunnel. In order to improve the construction speed, the field prefabricated bracket to connect the intermediate slab to the precast shield tunnel lining structure has been developed in the 'SPC (Steel Precast Concrete) bracket'. The experiments were performed for the full scale model in order to evaluate the performance of the 'SPC bracket', the structural stability was verified through the FEM analysis. The result of static loading test, no deformations or cracks of the bracket undergo the ultimate load was investigated. In addition, no pulling or deformation of the chemical anchor for fixing the bracket was measured. As a result of dynamic loading test, it was investigated that there is no problem in the chemical anchor for fixing the bracket. FEM analysis showed similar behavior to static load test and it was determined that there is no problem in serviceability and structural safety.

• Journal of the Korea Concrete Institute
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• v.14 no.4
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• pp.492-502
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• 2002

The dapped ends of the Gerber's beam were designed by PCI(Prestressed Concrete Institute) and CPCI(Canadian Prestressed Concrete Institute) methods. The depths of nibs with precast and topping concrete, which were halves of the total beam depth, were 77 cm md 18.2 cm, respectably. Shear tests were performed on four full scale beam ends. All specimens designed by PCI and CPCI methods showed crackings at the re-entrant coner of dap before the 32 ％ of full service design loading, and failed at the load level higher than their design strength but less than their calculated nominal strength. The specimens with increased hanger reinforcement show more effective in development of initial crackings, more ductile in failure with distributed crackings, and failed in higher strength than those of PCI requirement. The tested specimens designed by CPCI method were more ductile in failure than those of the PCI methods.