• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.163-168
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• 2001

Punching shear in concrete slabs is a serious problem in certain structural systems, such as flat slab. In this study, mechanical improvement between specimens which are unstrengthened and strengthened with steel plate and fiber panel is experimentally investigated. The strengthened bridge deck specimens had increment of strength and broke down with punching shear failure. Strengthening ratio should be considered to restraint punching failure.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.428-431
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• 2004

Smart structural system is defined as structural system with a certain-level of autonomy relying on the embedded functions of sensors, actuators and processors, that can automatically adjust structural characteristics, in response to the change in external disturbance and environments, toward structural safety and serviceability as well as the extension of structural service life. In this study, carbon and glass hybrid fiber materials were investigated fundamentally for the applicability of self diagnosis in smart concrete structural system as embedded functions of sensors.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.763-768
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• 2000

The purpose of this paper is to predict the flexural strengthening of reinforced concrete beams by the external bonding of carbon fiber reinforced plate(CFRP) to the tension face of the beam. Used computational equation is derived by relation of stress an strain. This equation is applied to four-nondamage beam and tow-preloading beam. Six scale beams were tested to evaluate the strength enhancement provided by the CFRP. And describes the strength enhancement provided to the flexural capacity of reinforced concrete beam by the external bonding of CFRP. An inelastic section analysis procedure was developed that accurately predicts the load displacement response of the retrofitted beams.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.477-480
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• 2004

This paper present test result to develop wedge-type anchor system for external prestressing method with CFRP. The test results indicated that the lower a slope angle and elastic of wedge are, the higher ultimate strengths are for plate types. Bar types showed premature failure because of local high stress in FRP of anchor system. Therefore, to improve the strength for bar types needs further work of strengthening sleeves, slope angles of wedge and materials.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.193-196
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• 2006

Unlike external bonded plate or carbon fiber, the external unbonded strengthening has some advantages in speed and simplicity of installation. It is not required surface preparations and not affected by environmental conditions. A set of six laboratory tests on RC beams strengthened using the technique are reported, results compared with non-strengthened specimens. The main test parameters are the cross-sectional area of the high-tension bar and the distance of stirrups. Test result show that the beams reinforced are superior to reference specimens, especially for the strength and deformation capacity. Also, it is shown that good efficiencies can be achived in shear strength of the beam.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.117-118
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• 2020

The masonry structure is constructed by cement mortar binding material of brick objects and uses reinforced hardware (connected hardware or wall tie) together when building. However, over time, the corrosion of reinforced steel and the deterioration of joint mortar as well as bricks cause the risk of collapse. In particular, when the externally decorated brick wall is installed on the concrete girder for each floor, the angle bracket is not constructed or corroded, the full-layer weight load is applied to the wall of 0.5B, which is an example of full-scale or collapse. The purpose of this study is to provide numerical information on the reinforcement design by experimentally studying the structural performance of concrete reinforcement brackets that reinforce the vertical load of the exterior wall.

• Management & Information Systems Review
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• v.7
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• pp.141-168
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• 2001

The causes that the transparency of Korean accounting information was rated low, a short supply of faithful and transparent accounting information from the limitation of external audit environment must be pointed out. Purpose of the external audit is a expression of the auditors about that financial statements an enterprise made public were appropriately drew up in accordance with the corporate accounting principles from important point of view. Analysis of the audit opinion and so fourth according to 6,541 individual audit reports and introduced to the bill securities forward committee as a subject of external audit according to the raw of corporation external audit show that considerable change to the contents of audit report. This show as it is that uncertainty of future that is now being faced by our enterprise, because corporation which present audit reports since 1997 because of enterprise dishonor and contents of existence probability as a continued enterprise following to general economic crisis after 1998 occupy important position in special matters of audit report. Also, increase in special matters is due to application of the corporate accounting principles revised on December 11, 1998. In 1999, audit opinion under limitation(limitation, incongruity and rejecting opinion) increased greatly according to existence doubt as a continued enterprise, and this is the consequence of strengthening audit to the continues enterprise because of limited enterprise dishonor according to the stagnancy of business activities after 1997. Now financial supervisory service put in effect electromagnetic public announcement system about a project report of listed corporation (including an audit report) keeping pace with a documentary public announcement system as first phase since 1999 and expand to the unlisted corporation from 2000. As electromagnetic public announcement of public announcement documents including audit documents of external audit subject get a duty, approach of external user to the accounting information will be easier. Fixation of this system will make deep and wide analysis to the audit opinion, and this will draw up a plan to reconsider confidence of accounting information.

• PNF and Movement
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• v.21 no.3
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• pp.309-317
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• 2023

Purpose: This study set out to investigate the effects of prone hip extension with knee flexion (PHEKF) exercises according to external load on the thickness of the gluteus maximus (Gmax) and biceps femoris (BF). Methods: Twenty-three healthy men participated in this study. All subjects randomly practiced PHEKF under the burden of external loads created by sandbags (0 kg, 1 kg, and 2 kg). Rehabilitative ultrasound imaging (RUSI) was used to measure the thickness of the Gmax and BF during the PHEKF with different external loads. Results: The thickness of the Gmax was highest during the 2 kg resistance exercise and lowest at 0 kg. The thickness of the Gmax was significantly increased at 1 kg and 2 kg compared to 0 kg and significantly increased at from 1 kg to 2 kg (p < 0.05). The thickness of the biceps femoris was highest at 0 kg and lowest at 2 kg. The thickness of the biceps femoris muscle was significantly reduced at 1 kg and 2 kg compared to 0 kg (p < 0.05), but there was no significant difference between 1 kg and 2 kg (p > 0.05). Conclusion: The thickness of the Gmax was increased by applying PHEKF with a higher external load, whereas the muscle thickness of the biceps femoris decreased. These results suggest that the application of external loads during PHEKF exercises may be an effective method for selective strengthening of the Gmax.

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.2
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• pp.77-86
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• 2020

Nonlinear static analysis and preliminary evaluation were performed in this study to evaluate the seismic performance of unreinforced masonry buildings subjected to various soil conditions based on the revised Korean Building Code. Preliminary evaluation scores and nonlinear static analyses indicated that all buildings were susceptible to collapse and did not reach their target performance. Therefore, retrofit of those building models was carried out through a systematic procedure to determine areas to be strengthened. It was possible to make most building models satisfy performance objectives through the reinforcement alone of damaged external shear walls. However, the application of a preliminary evaluation procedure to retrofit design was found to be too conservative because all the retrofitted building models verified with nonlinear static analysis failed to satisfy performance objectives. Therefore, it is possible to economically retrofit unreinforced masonry buildings through the fortification of external walls if a simple evaluation procedure that can efficiently specify vulnerable parts is developed.

• Journal of Digital Convergence
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• v.8 no.2
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• pp.29-42
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• 2010

To improve the performance of R&D investments, government has taken great efforts for advancing the structure and process in R&D systems. However, due to the drastic internal/external changes in the technological environment and the steady increase of investment scale, the necessity for a innovative approach which accomplishes returns to scale through the utilization of various external resources is emerging. In this regard, open innovation approach can minimize the possibility of government failures by strengthening the absorptive capacity of external resources and enhancing the cooperation and participation of diverse innovative participants within the R&D system. This paper evaluates the previous researches and government policies concerning the performances of government R&D investments, and presents the connectivity between open innovation and its possible contribution to the improvement of R&D investment performances.