• Journal of the Korean GEO-environmental Society
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• v.25 no.2
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• pp.5-14
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• 2024

Reinforced concrete bridge decks are the first to be damaged by vehicle loads and rain infiltration. Concrete deterioration primarily occurs owing to the corrosion of rebars and other metal components by chlorides used for snow and ice melting. The structural condition and concrete deterioration of the bridge decks within the pavement were evaluated using ground-penetrating radar (GPR) survey data. To evaluate concrete deterioration in bridges, it is necessary to develop GPR data analysis techniques to accurately identify deteriorated locations and rebar positions. GPR exploration involves the acquisition of reflection and diffraction wave signals due to differences in radar wave propagation velocity in geotechnical media. Therefore, a full-waveform inversion (FWI) method was developed to evaluate the deterioration of reinforced concrete bridge decks by estimating the radar wave propagation velocity in geotechnical media using GPR data. Numerical experiments using a GPR velocity model confirmed the deterioration phenomena of bridge decks, such as concrete delamination and rebar corrosion, verifying the applicability of the developed technology. Moreover, using the synthetic GPR data, FWI facilitates the determination of rebar positions and concrete deterioration locations using inverted velocity images.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.664-667
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• 2004

It may have to establish the definite standard for performance evaluation basis about cementitious waterproofing material in job site that applied the method of construction formed cement waterproof course on concrete surface In present paper shows the effective selection method of waterproof layer of optimum thickness for economic performance as evaluating of the need thickness on waterproof property of penetrating waterproofing material.

• Journal of Trauma and Injury
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• v.25 no.3
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• pp.94-96
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• 2012

Duodenal injuries following a blunt or penetrating trauma are uncommon and account for just 3% to 5% of all abdominal injuries. About 22% of all duodenal injuries are caused by blunt trauma. An overlooked injury or delayed diagnosis of duodenal injury may lead to increased mortality and morbidity. We report two cases of a duodenal injury following blunt abdominal trauma.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.525-528
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• 2011

Noise emitted by driving cars affects our daily life, penetrating wherever man lives or works. There are three types of possible sound emitting processes that are aerodynamic sources, air pumping and tire vibration. In this paper, a theoretical model has been studied to describe the sound radiation by the surface vibration of running tires and experimental verification has been conducted to evaluate sound radiation characteristic due to tire vibration.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.980-986
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• 2004

So far systematic and reliable methods for the investigation of track substructure (ballast and subgrade) are not developed yet. This study presents the applicability of GPR (Ground Penetrating Radar) and PBS (Portable Ballast Sampler) to the evaluation of railway trackbed conditions. Including FWD (Falling Weight Deflectometer) often used to evaluate the subsurface conditions of pavement, the standard system for assessing trackbed conditions will be developed in the future.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.401-404
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• 1989

Some magnetic probes for theta-pinch experiment have been constructed. Methods of building the coil, conecting it to the oscilloscope, shielding and enclosing the probe are discribed. Such a probe has been used to measure the magnetic flux penetrating it within theta - pinched plasmas.

• 한국지구물리탐사학회:학술대회논문집
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• 2006.06a
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• pp.31-34
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• 2006

Laboratory experiment of polarimetric GPR measurement was conducted for the purpose of estimating subsurface inhomogeneity. Tow realization of inhomogeneous subsurface media were made by burying stone objects of different dimensions in homogeneous dry sand. Polarization ratio of cross polarization to co polarization data were examined to find their obviously distinguishable behavior.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.209-216
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• 2003

• Journal of Chest Surgery
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• v.27 no.3
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• pp.255-258
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• 1994

I have experienced with 6 cases traumatic injury of diaphragm from May 1991 to October 1993 at the Youngdong Hospital in Tonghae. This cases included 4 penetrating injuries and 2 nonpenetrating injuries. Associated injuries occurred 4 cases and 2 cases occurred stomach herniation. All cases, operative treatment were done. Result of this treatment cases were good. Complications included 1 early death and only 1 wound infection. Cause of death was related to associated injury.

• Journal of Chest Surgery
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• v.28 no.12
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• pp.1197-1200
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• 1995

Since diaphragmatic injuries are difficult to diagnose, those that missed may present with latent symptoms.Delayed diaphragmatic hernia is very rare and occurs commonly after penetrating or blunt trauma. Recently we had experience with two cases of delayed diaphragmatic hernia after left nephrectomy.They were operated by herniolysis and closure of diaphragm using prosthetic patch[Dura, Dacron through the left thoracotomy. Postoperative courses were uneventful.