• Journal of Biomedical Engineering Research
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• v.16 no.3
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• pp.359-366
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• 1995

The parameter, B/A, quantifies nonlinearity of the pressure-density relationship of propagation medium. This study investigated quantitative evaluation technique for healing fractured bones using this ultrasonic nonlinear parameter, B/A, obtained by the second harmonic amplitude method. A series of fundamental experiments were performed on cylinder phantoms made of aluminium, which demonstrated potential capability of nonlinear parameter B/A in the diagnosis of healing fractured bones using ultrasound.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.6
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• pp.625-630
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• 2007

Fractures of the mandibular condyle are account for between 26% and 57% of all mandibular fractures. Clinicians should decide how to treat the fractured condyle with many factors considered. Many surgical methods have been developed to reduction of fractured condyle and it' s internal fixation. In open reduction of fractured condylar neck and subcondyle, retromandibular approach offers a safe and effective approach for direct fixation due to easy access and low surgical morbidity.

• Journal of the Korean Mathematical Society
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• v.38 no.4
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• pp.723-761
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• 2001

The objects of this paper are to formulated a model for the transport of a chain of radioactive waste products in a fractured porous medium, to devise an effective and efficient numerical method for approximating the solution of the model, and to demonstrated the convergence of the numerical method. The formulation begins from a model in an unfractured (single porosity) medium, passes through a double porosity model in a fractured medium, and ends with a modified single porosity model that takes the relevant time scales of the flow and the nuclear decay.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.132-135
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• 2001

To understand and compare tracer transport in fractured and porous media. multiple tracer tests were conducted in Wonju and Uiwang sites. The target media were fractured in Wonju site and porous in Uiwang site. It was known that groundwater flow for the two hydrogeologic systems could be represented using a EPM approach. However, the tracer transport in the two aquifer systems was greatly different. In this study, we analyzed the different tracer transport behavior in the two systems, from which our understanding of the tracer dispersion was greatly enhanced. we used bromide and chloride as tracers.

• 한국지구물리탐사학회:학술대회논문집
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• 2003.11a
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• pp.150-155
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• 2003

Fractures in the form of micro cracks are commonly found in natural rocks. A rock behaves in a complex way due to fracture; in particular, the anisotropic strength of a rock material is significantly influenced by the presence of these fractures. Therefore, it is essential to understand the failure mechanism of a fractured rock. In this study, a fractured rock is formulated in terms of fabric tensor based on geometric and mechanical simplifications. In this way, position, density and shape of fractures can be determined by the fabric tensor so that rocks containing multi-fractures can successfully be modeled. Also an index to evaluate the degree of anisotropy of a fractured rock is proposed. Hence, anisotropic strength of a rock containing fractures under uniaxial compression condition is estimated through a series of numerical analyses for the multi-fractured model. Numerical investigations are carried out by varying the fracture angle from $0^{\circ}\;to\;90^{\circ}$ and relationship between uniaxial compression strength and the degree of anisotropy is investigated. By comparing anisotropic strength of numerical analysis with analytic solution, this study attempts to understand the failure mechanism of rock containing fractures.

• Nuclear Engineering and Technology
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• v.44 no.1
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• pp.79-88
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• 2012

Migration tests were performed with conservative tracers in a fractured zone that had a single fracture of about 2.5 m distance at the KURT. To interpret the migration of the tracers in the fractured rock, a solute transport model was developed. A two dimensional variable aperture channel model was adopted to describe the fractured path and hydrology, and a particle tracking method was used for solute transport. The simulation tried not only to develop a migration model of solutes for open flow environments but also to produce ideas for a better understanding of solute behaviours in indefinable fracture zones by comparing them to experimental results. The results of our simulations and experiments are described as elution and breakthrough curves, and are quantified by momentum analysis. The main retardation mechanism of nonsorbing tracers, including matrixdiffusion, was investigated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.104-105
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• 2008

According to previous report, aged sleeves of old transmission line showed several defaulted installation patterns, which is biased or corrosive-fractured of steel sleeve installed cases. The latter case occupied almost 25 percent of investigated aged sleeves. These defects can cause serious accidents such as rapid increasing of sag or falling out of overhead conductor from sleeves. This paper studies thermal properties and tension for ACSR conductor in case of fractured steel sleeve model. The detailed results were presented in the text.

• Journal of Haehwa Medicine
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• v.8 no.1
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• pp.727-738
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• 1999

Sintongchugoetang(CTCOT) is one of the importent prescription that has been used in oriental medicine(yyilimgaechak) for helling fractured condition. The study was done to evaluate effects of CTCOTwater extract on the tibia fractured rats. The result were obtained as follows : 1. In the change of X-ray, experimental group was significantly effected than control. 2. In the changes of body weight, experimental group was decreased than control. 3. In the change of Ca, P and ALP(alkaline phosphatase) on serum, all experimental group was not significant. 4. In the change of bone tissue, experimental group was was significantly effected than control in callus formation and maturity. From above results, CTCOT was had significant effects on the helling of fractured in rats, so it is expected to clinical application.

• Journal of Haehwa Medicine
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• v.8 no.1
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• pp.675-687
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• 1999

Gamigungguitang(GMGGT) and GamigungguitangGaNokyong(GMGGTN) are one of the importent prescription that has been used in oriental medicine(dongyyibangjehak) for helling fractured condition. The study was done to evaluate effects of GMGGT and GMGGTN water extract on the tibia fractured rats. The result were obtained as follows : 1. In the change of X-ray, all experimental group was significantly effected than control. 2. In the changes of body weight, all experimental group was decreased than control. 3. In the change of Ca, P and ALP(alkaline phosphatase) on serum, all experimental group was not significant. 4. In the change of bone tissue, all experimental group was was significantly effected than control in callus formation and maturity. From above results GMGGT and GMGGTNBSH were had significant effects on the helling of fractured in rats, so it is expected to clinical application.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3390-3397
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• 2022

Among the different techniques available, nuclear methods, including gamma-gamma logging tools, are of special importance. Though the real environment which surrounds the drilled borehole is a complex fractured medium which the fluid can flow through the porosities, simulation studies generally use the traditional model of a homogeneous mixture of formation and the liquid. Considering a previously published study, which shows that modeling of fluid flow in fractured reservoirs and simulating the formation as an inhomogeneous fractured medium leads to different results compared with those of homogeneous mixture, here we study the effect of the presence of drilling fluid (mudcake) on the response of the detectors in both the models. To study this effect, a typical gamma-gamma logging tool was modeled by using the MCNPX Monte Carlo code. The results show that the responses of the detectors in the mixture model in the presence of various thicknesses of mudcake are sensitive to the density of the formation material. However, this effect is not notable in the inhomogeneous fractured medium. These results emphasize the importance of the model employed for simulation of the medium in gamma-gamma well-logging.