• Journal of Chest Surgery
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• 제22권4호
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• pp.609-619
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• 1989

During aortic valve surgery, cardioplegic solution is delivered through direct cannulation of both coronary ostia. Since this approach may cause an intimal injury leading to acute dissection or late ostial stenosis, this study was undertaken to evaluate myocardial protective effect of retrograde perfusion of cardioplegia [RCSP <% RRAP] in 18 clinical cases, which were compared with antegrade perfusion of cardioplegia in 27 clinical cases. This study were investigated 1] cease and return of electromechanical activity after cardioplegia infusion 2] the myocardial temperature during operation 3] the aortic cross clamping time and total bypass time 4] frequency of DC shock for defibrillation 5] need for inotropic drugs after operation 6] electrocardiographic evidence of myocardial infarction or ventricular arrhythmia after operation 7] the enzymes activity during preoperative and postoperative period as an evaluation of myocardial ischemic injury and 8] operative mortality rate The combination of retrograde cardioplegia and topical cooling with ice slush yielded promptly hypothermia of myocardium and shorter aortic cross-clamping time compared with antegrade cardioplegia [P < 0.05]. The temperature of the interventricular septum was maintained below 20oC by continuous perfusion or intermittent perfusion of cold blood cardioplegia and other results were no statistically significant difference between the two methods [P >0.05]. This technique provides clear operative field and avoids some serious complications which are caused by coronary ostial cannulation. These results suggested that the retrograde perfusion of cardioplegia is a simple, safe, and effective means of myocardial protection during open heart surgery.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.34-36
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• 2006

In this paper, we will treat the diagnosis problem to accurately determine fault types. The judgement of fault types is accomplished by observing the cluster newly formed with faults and clustering the input current waveforms to intrinsically show the conditions with the dignet that is a clustering algorithm. The types of input current waveforms are, however, constrained during normal operation, though it considers the load character. In case of faults. new clusters are generated outside the clusters. which appear during normal operation, because the input current waveforms of the induction motor are generated by the type which is not observed in case of faults. The diagnosis about the types of faults is essential to building a fault tree about the induction motor, and it removes the causes of the faults using a fuzzy logic. We, first, constitute a fault tree, which connects with the parts and the entire system of the induction motor, and investigate fault modes which can be generated from the fault tree and the relationship of the cause and the effect of each part (of the motor). Also, we distinguish the faults of each part by means of inducing the said of fuzzy relation equations encapsulating the relationship of the fault modes and each part.

• 한국의류학회지
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• 제37권7호
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• pp.837-851
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• 2013

This study investigates the relationship between dystopian ideas and fashion since the $20^{th}$ century and examines the social meaning of fashion influenced by dystopian ideas. From the 1900s to the 1950s, the idea of dehumanization by authoritarian governments and technology gave rise to fashion for freedom and self-introspection, which includes surrealistic fashion and beat style. In the 1980s and 1990s, a society marked by monopolistic power and the hi-tech control of humans was regarded as dystopia. It influenced a fashion that expressed dehumanization by hi-tech means such as cyberpunk style and designs that depicted or used electronic elements. The ongoing fear of ecological disaster since the late $20^{th}$ century also influenced designers to present collections concerned with environmental problems. Designers have created designs with printed messages on environmental issues or designs that express environmental devastation, and protective designs that use hi-tech fabrics or mechanical devices. Fashion influenced by dystopian ideas expressed contemporary fears, provided a critical view of society through defamiliarization, and sought problem-solving actions and alternatives to change or cope with the dystopian situation. Dystopian fashion gave society a chance to face contemporary problems and pursue a better society.

• Journal of Microbiology and Biotechnology
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• 제14권6호
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• pp.1333-1337
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• 2004

Oxidants such as hydrogen peroxide are powerful inducers of cell damage, ageing, and apoptosis. Since clusterin, a 75-80 kDa mammalian glycoprotein, is frequently found to be inducible in apoptotic cells and tissues, this study inquired into whether this would be a protective mechanism against further cell death. The aim was to find out whether overexpression of clusterin could protect cells from oxidant­induced stress and apoptosis. To clarify this issue, we generated and analyzed stable cell lines expressing fusion proteins of a rat clusterin with an enhanced green fluorescent protein (EGFP). When treated with varying concentrations of hydrogen peroxides, clusterin transfectants indeed showed increased resistance to apoptosis and exhibited a much higher survival rate than mock-transfected cells. On the other hand, neither intracellular re-distribution nor local concentration of clusterin-EGFP was observed, which leaves the question open about its anti-apoptotic mechanism. In conclusion, the overexpression of clusterin provides a means for protecting cells against oxidative stress and subsequent cell death.

• 열처리공학회지
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• 제4권4호
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• pp.1-14
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• 1991

In PECVD(Plasma-Enhanced Chemical Vapor Deposition) process, titanium nitride is thin and its adhesion is poor for the protective coatings. Therefore it has been studied that intermediate layer forms between substrate and TiN thin film. Using R.F. plasma nitriding, nitride layer was first formed, then TiN thin film coated by PECVD. The chemical composition of the coatings has been characterized using AES, EDS and their crystallographic structure by means of XRD. Mechanical properties such as microhardness and film adhesion have also been determined by vickers hardness test, scratch test and indentation test. As a result, there was no difference in chemical composition and structure between the TiN deposition only and the composite of TiN deposition on nitrided steel. It was found that nitrided substrate increased the hardness of TiN coatings and was beneficial in preventing the plastic deformation in the substrate. Therefore the effective load bearing capacity of the TiN coatings on nitrided steel was increased and their adhesion was improved as well. According to the results of this study, the processes that lead to the formation of composite layers characterized by good working properties, i.e., high microhardness, adhesion and resistance to deformation.

• 한국주조공학회지
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• 제33권3호
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• pp.127-133
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• 2013

The influences of a small amount of CaO addition on the microstructure and corrosion behavior of AZ81 casting alloy have been investigated by means of optical microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, immersion and electrochemical tests. The added CaO led to the refinement of ${\alpha}$-Mg grains and the decrease in ${\beta}$ precipitate content by the formation of an $Al_2Ca$ phase. The AZ81-CaO alloy had a better corrosion resistance than the AZ81 alloy. The microstructural characterization on the corroded surface revealed that the enhanced corrosion resistance of the CaO-containing alloy may well be ascribed to the increased barrier effect of precipitates formed more continuously along the grain boundaries and the incorporation of Al and Ca elements into the corrosion film, by which it became more protective.

• 대한간호학회지
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• 제29권3호
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• pp.688-699
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• 1999

This study was to find out the perceptions of toward death and caring behavior of lay persons in one community : One Island in Puan County, Chonbuk. The methodology of this study was ethnography. For this study, the fieldwork was conducted from October 1997 to July 1998. Data collected by in-depth interview and participant observations. The participants consisted fo were 17 persons of both sexes. The key informants were four specific people. The result of this study is as follows ; The people perceived two different kinds of death. Normal death, which means death from old age. The person was respected as an ancestor God and was believed to exist forever with their offspring. Abnormal death was regarded as negative, many had fears toward this kind of death. The causes of abnormal death were supernatural phenomena and had absolute holy meanings. Whether death was good or bad, the death was not personal, but collective events as family or community affairs and was interpreted as death and birth for their offsprings. Funeral rites were family-centered and/or com munity-centered. They did normal procedures for normal deaths for abnormal deaths, there were many protective ceremonies(BuJungMagi : the prevention of the taboo of uncleanliness) for the remaining people. These ceremonies combined confucism and shamanism. Caring behavior for dying persons was ruled as community-centered, reciprocal and reality-centered principles.

• Archives of Pharmacal Research
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• 제21권5호
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• pp.508-513
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• 1998

The hepatoprotective effect of DA-9601, a quality-controlled extract of artemisisa asiatica, on liver damage induced by acetaminophen (APAP) and carbon tetrachloride ($CCI_{4}$) was investigated by means of serum-biochemical, hepatic-biochemical, and histopathological examinations. Doses of Da-9601 (10, 30, or 100 mg/kg) were administered intragastrically to each rat on three consecutive days i.e. 48 h, 24 h and 2 h before a single administration of APAP (640 mg/kg, i.p.) or $CCI_{4}$ (2 ml/kg, p.o.). Four h and 24 h after hepatotoxin treatment, the animals were sacrificed for evaluation of liver damage. Pretreatment of Da-9601 reduced the elevation of serum ALT, AST. LDH and histopathological changes such as centrilobular necrosis, vacuolar degeneration and inflammatory cell infiltration dose-dependently. Da-9601 also prevented APAP- and $CCI_{4}$-induced hepatic glutathione (GSH) depletion and $CCI_{4}$-induced increase of hepatic malondialdehyde (MDA), a parameter of lipid peroxidation, in a chemically induced liver injury by complex mechanisms which involve prevention of lipid peroxidation and preservation of hepatic GSH.

• 소성∙가공
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• 제8권3호
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• pp.295-295
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• 1999

In the present study, the corrosion behavior of AZ91D as-cast alloy was investigated form the viewpoint of the distribution aspect of precipitate ($Mg_{17}Al_{12}$) and the variation of Al concentration in the Mg-rich matrix. The dendrite arm spacing (DAS) of an as-cast specimen was measured as a function of degree which describes the distribution aspect of the precipitate, and the salt spray test was conducted for various grain-sired specimens fur 20 days. The dendrite arm spacing increased as the grain size increased to about 150㎛, but a constant value is indicated when the grain size exceeds that range. Although the relationship between the corrosion rate and grain size is of a nonlinear type, the linear trend between the corrosion rate and the dendrite arm spacing is maintained for the overall range of dendrite arm spacing. Since the precipitate in the as-cast alloy is discontinuously distributed, this linear relationship means that the variation of Al-solute concentration in the Mg-rich matrix has a more potent effect than the protective action of the precipitate on the corrosion behavior of an as-cast alloy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.488-490
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• 2001

A dispered power system means a little bit of small power generation equipment located near the power-damend areas. Due to no power supply line, such a power source is very favorable for the decrease in loss of electric power supply, in comparison to the giantly focused power source, Because of small power source, this power source also corresponds promptly to the variation of power demend. On the basis of energy saving, environmental reservation, and utilization of natural or unused energy, solar power plants can be introduced into the residence section of cities and small water or wind-power plants near the urban areas. In case of Korea, some wind farm have been introduced into Cheju island, Condensed introduction of several small power sources into an used distribution line may, however, result in a big problem, it is, therefore, necessary that protective-cooporative plans between power quality and distribution line should be introduced for efficient utilization of KEPCO distribution system.