• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.87-92
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• 2001

Reinforced concrete have defect in durability due to carbonation, freezing and thawing, and penetration of chloride ions with time in spite of superb structure. Especially steel corrosion in concrete due to penetration of chloride ions have result in a marked decline in service life. The principal purpose in this study is to see effect of sacrificial anode cathodic system, one of the electrochemical methods in order to the control of steel corrosion in concrete. There are chloride content in concrete in cracked and no cracked specimen with cathodic protection. To recognize the effect of sacrificial anode cathodic protection, Instant-off potential are measured. We have the excellent effect for control steel corrosion adaption sacrificial anode cathodic system.

• Journal of Chest Surgery
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• v.26 no.9
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• pp.701-704
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• 1993

Four to seven percent of infants born with aortic atresia have a normal-sized left ventricle in association with a ventricular septal defect and a normal mitral valve. In contrast to the more common group of infants with aortic atresia whose left ventricle is hypoplastic, this important subgroup has potential for complete operative correction involving both the right and left ventricle. Our approach was to perform complete repair at one stage. The patient who underwent single-stage repair was discharged from the hospital in good condition. Achieving a physiologically normal circulation simplifies the postoperative management of this condition.

• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.128-135
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• 1998

The paper gives a brief introduction to protonic defects and their chemistry, thermodynamics and transport in oxides. The temperature dependence of the equilibrium concentration of protons is illustrated and compared for different acceptor-doped oxides. The difficulties of saturating as well as emptying the oxides of protons are discussed. In order to illustrate the possibility of lattice relaxation of defects, a conceptual study is made of a case where the enthalpy of dissolution of protons(water) at the cost of oxygen vacancies is assumed dependent on the concentration of vacancies. It is shown how this changes the behavior of hydration curves vs temperature and water vapour pressure. finally, a discussion is given on the water uptake in heavily oxygen deficient oxides; how water uptake may affect order-disorder in the oxygen sublattice and eventually lead to defective, disordered or ordered oxyhydroxides or hydroxides of potential interest as intermediate temperature proton conductions.

• Journal of Korean Neurosurgical Society
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• v.58 no.3
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• pp.294-297
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• 2015

Spinal cord herniation is a rare condition that has become increasingly recognised in the last few years. The authors report a case of idiopathic spinal cord herniation in a 33 year old woman performed with progressive Brown-Sequard syndrome. The diagnosis was made on MR imaging. After repairing the herniation, the patient made a gradual improvement. Potential causes are discussed, including a possible role of dural defect. In conclusion, idiopathic spinal cord herniation is a potentially treatable condition that should be more readily diagnosed that increasing awareness and improved imaging techniques.

• Smart Structures and Systems
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• v.17 no.5
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• pp.795-817
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• 2016

A non-contact, in-situ and non-invasive technique for health monitoring of submerged fiber reinforced polymers (FRP) laminates has been developed using ultrasonic guided waves. A pair of mobile transducers at specific angles of incidence to the submerged FRP specimen was used to excite Lamb wave modes. Lamb wave modes were used for comprehensive inspection of various types of manufacturing defects like air gaps and missing epoxy, introduced during manufacturing of FRP using Vacuum Assisted Resin Infusion Molding (VARIM). Further service induced damages like notches and surface defects were also studied and evaluated using guided waves. Quantitative evaluation of transmitted ultrasonic signal in defect ridden FRPs $vis-{\grave{a}}-vis$ healthy signal has been used to relate the extent of damage in FRPs. The developed technique has the potential to develop into a quick, real time health monitoring tool for judging the service worthiness of FRPs.

• Tribology and Lubricants
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• v.20 no.2
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• pp.102-108
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• 2004

In this paper, friction and wear behaviors between monocrystalline, defect-free copper and carbon on the atomic scale are investigated by using 2-dimensional molecular dynamics simulation. It is assumed that all interatomic forces are given by Morse potential. The deformation of carbon is assumed to be neglected and vacuum condition is also assumed. Average friction and normal forces for various surface conditions, various scratch speeds and scratch depths are obtained from simulations. Changes of wear behaviors for various scratch speeds and surface conditions are investigated by observing snapshots in scratch process. The effects of surface conditions, scratch speeds, and scratch depths on the friction force, normal force, and friction coefficient are also investigated.

• Journal of Applied Reliability
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• v.5 no.2
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• pp.221-239
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• 2005

General chip SMD parts(chip resistance, chip capacitor, chip varistor etc.) are very wide used electronics parts for IT units. But, failure modes are indistinct for these chip parts. In factory and field the failure modes are recognized to accidental failure mode caused by potential defect. In this paper used chip varistor ALT(Accelerate Life Test) test for verify general failure modes in chip SMD parts. Also the results are useful for general chip SMD ALT tests.

• Journal of the Korean Ceramic Society
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• v.36 no.9
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• pp.991-996
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• 1999

Effect of solution property on the weight varation and microstructural change of film was studied by electrophoretic deposition in order to obtain a homogeneous and dense zirconia film. As a result of weight kinetics of film which obtained in alcohol or aqueous solution having different polarity experimental data showed large deviation from theoretical ones calculated by Zhang's kinetic model. It had been shown that the weight affecting factors was largely dependent on properties other than dielectric constant and viscosity of solvent zeta potential appiled field and time. In initial stage a main factor of the drastic weight increase was the capillary drag of porous substrate. The cause of weight decrease with time in aqueous solution after 300 s was attributed to the defect of film by sagging and electrolytic reaction. The electrolyte film which prepared in alcohol solution with good wetting for substrate had better homogeneous and dense microstructure than one in aqueous solution with high surface tension.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1288-1290
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• 2005

We report on the structural and electrical properties of amorphous Yttria-stabilized zirconia (YSZ) thin films which are the potential high-k gate dielectric material of organic thin film transistor (OTFT). To investigate the influence of the oxygen flow rate on the structural and electrical properties of the YSZ films, XRD, XPS, J-E, I-V were carried out in this work. Oxygen vacancies are expected to be the most predominant type of defect in metal-oxide dielectrics. The leakage current density decreased mainly because of the reduction of oxygen vacancies with increasing oxygen flow rate.

• Journal of the Korean Ceramic Society
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• v.38 no.6
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• pp.499-505
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• 2001

The behaviour of ionic compound crystals under combined chemical and externally applied electrical potential gradients is discussed. Firstly, a systematic overview is given. Then a formal analysis follows. The transport equations of the ions and the electric defects predict that even with reversible electrodes demixing, and in particular decomposition of the compound will occur if the applied d.c. current density is sufficiently high. These predictions are illustrated by appropriate experiments. With the help of the solid solution (Me, Fe)O, where Fe-ions are the dilute species, we investigate experimentally the behaviour of a ternary ionic crystal under a d.c. electric current load. All the compounds were placed in a galvanic cell, and the internal reactions which then could be observed were driven by the electric field in this cell. In addition, we discuss the influence of the electric field on the classical solid state reaction AX+BX=ABX$_2$, if again the reaction couple is placed in a galvanic cell.