• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1624-1626
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• 1999

PD in defect of solid insulation system is very harmful since It often leads to deterioration of insulation by the combined action of the discharge ions bombarding the surface and the action of chemical compounds that are formed by the discharge. PD can indicate incipient failure, so it has been used to determine degradation of insulation. In this paper. we investigated PD in defects of solid insulation by using statical method and classified PD patterns with surface discharge, electrical tree and void discharge by using Kohonen network. we used peak charge, average discharge power, average discharge current, repetition rate, skewness, kurtosis, QN of the max pulse height vs. repetition rate $H_q(n)$ for analysis and classification.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.3
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• pp.289-297
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• 2004

Emissions of volatile organic compounds and odors from various industrial processes not only pollute surrounding life environments, but also lead to the deterioration of the working environments, causing various industrial health and business problems. These pollutants are usually stimulating, irritating, malodorous and sometimes carcinogenic, Which should be reduced in the pollutants formation, stage, but the practical processes do not allow This paper describes the major sources of VOC and odors, and their sampling/analysis methods. Furthermore, various removal technologies for these pollutants are suggested, which particularly include the characteristics of the catalytic and scrubber/carbon filter combined process, and even process design technologies.

• Journal of Chest Surgery
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• v.27 no.9
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• pp.793-797
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• 1994

Constrictive pericarditis is often accompanied with ~brothorax and deterioration of cardiac, hemodynamic functions. Surgical relief of fibrous peel causes remarkable improvement in pulmonary, cardiac, hemodynamic function, and subjective symptoms. We experienced 4 cases of constrictive pericarditis combined with bilateral ~brothorax after bilateral pleural effusion caused by tuberculosis and non-specific inflammation. Pleural decortication and pericardiectomy were done at the same time through anterolateral thoracotomy with sternal transection[3 patients] and median sternotomy incision[l patient]. Low cardiac output was the most common complication. With left anterolateral thoracotomy, we could prevent the hypotension from massive retraction for dissecting by median sternotomy, which was good for dissecting from anterior wall of left ventricle to posterior wall of left ventricle and surrounding phrenic nerve. It was enough to dissect the portion being through hard to dissect, right atrium, SVC and IVC.

• Journal of Korean Neurosurgical Society
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• v.42 no.1
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• pp.49-52
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• 2007

The authors report a unique case of unilateral Moyamoya disease with a rare combination of arteriovenous malformation (AVM) who presented with intracerebral hemorrhage (ICH). A 50-year-old man suffered from sudden onset of mental deterioration and right hemiparesis. Brain computed tomography (CT) showed intracerebral hemorrhage on left thalamus. Brain CT angiography and cerebral digital subtraction angiography (DSA) revealed AVM combined with unilateral moyamoya disease involving left middle cerebral artery (MCA) and choroid plexus in left lateral ventricle. Intraventricular hemorrhage and hydrocephalus were managed conservatively. A rare case of unilateral Moyamoya disease accompanied by a cerebral arteriovenous malformation is described and discussed with review of pertinent literature.

• Journal of Chest Surgery
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• v.51 no.4
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• pp.283-285
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• 2018

A 73-year-old woman who underwent combined bioprosthetic mitral valve replacement, tricuspid ring annuloplasty, and coronary artery bypass grafting 12 years previously visited our clinic due to aggravated dyspnea caused by structural valve deterioration of the mitral prosthesis. Because aortic or femoral artery cannulation and cross-clamping would have a high risk of stroke owing to severe calcification of the ascending aorta and ilio-femoral vessels, and because there was a risk of redo sternotomy due to the patent bypass grafts, a comprehensive approach including axillary artery cannulation, a minimally invasive right thoracotomy approach, and a clampless hypothermic fibrillatory arrest technique was used during redo mitral valve replacement.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.241-244
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• 2006

The basic prediction model was constructed to obtain optimal maintenance method for concrete structure under marine environment by exploring the mechanism of mono and combined deterioration in lab. This model was planned to be upgraded with data acquired from several exposure specimens under same environment as structures. The computer program developed to give useful guidance observer would be improved. Several repair materials and repair construction methods applied to exposure specimens will be tested for its performance of prohibit salt attack and freezing & thawing action during experimental period about ten years. All of these data could be available to complete the prediction system. The manager will be able to use the system for optimal maintenance of marine concrete structures.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.5-8
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• 2006

In this study, various fundamental experiments including durability and time-dependent deformation are performed to compile a database for a utilization of high-strength concrete for PSC bridges. In the mix design, concrete strength at early age when prestressing forces are introduced to the PSC member and slumpflow suitable for pumping of concrete are considered to make a concrete fit for PSC bridges. The main parameters investigated are the kinds and replacement ratios of mineral admixtures and low-heat cement. Experimental tests on durability include penetration of chloride ions, freezing-thawing, combined deterioration, and simple adiabatic temperature rise test. In addition, time-dependent deformation such as creep, drying and autogenous shrinkage, which is particularly important factor in the design and construction of PSC bridges, is tested and analyzed.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.735-738
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• 2005

Most concrete is recently made of an aggregate which is properly absorbed, and carried in it in order to do capability at every fields. We have been close to demand new capability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate. Therefore, For solving the problems we apply to a packing method for using dried materials. That is to say it is a kind of making into an instant. In this study, There is a purpose to present fundamental data, comparing and analyzing a phenomenon about aggregate's absorption following the rate of adding water, for using existing materials.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.90-93
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• 2003

The most common deteriorating processes of concrete structures in the world-wide are carbonation and chloride ion. In this paper, chloride profiles of carbonated concrete is predicted to considering two layer composite model, which is based on Fick's 2nd law. From the experimental result on combined deterioration of chloride and carbonation, it was examined that high chloride concentration was built up to 3-5㎜ over depth from carbonation depth. The analytical modeling of chloride diffusion, which was based on the Fick's 2nd law of diffusion, was suggested to depict the relative influence of the carbonation depth.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.493-496
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• 2003

Most concrete is recently made of an aggregate which is properly absorbed, and carried in it in order to do capability at every fields. We have been close to demand new capability of high flowing and enduring for specific concretes. That is difficult to cope with claiming the efficiency on deterioration from lack of a high quality aggregate. Therefore, for solving the problems we apply to a packing method for using dried materials. That is to say it is a kind of making into an instant. In this study, There is a purpose to present fundamental data, comparing and analyzing a phenomenon about aggregate absorption following the rate of adding water, for using existing materials.