• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.171-174
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• 1990

When load areas on a feeder are deenergized due to faults,operaters need to identify nelghboring feeders, try to restore customers and minimize out-of-service areas. These cases include knowledge of system states and various constraints such as voltage drop. This paper concerns the load transfer infault restoration. Also, it is considered the operating constraints such as line current capacity, relay trip current, transformer capacity, voltage drop and line loss. The expert system is able to propose the optimal load transfer method by anallzing system states and considering constraints.

• Journal of Chest Surgery
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• v.11 no.4
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• pp.422-427
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• 1978

Alterations in the serum and urine potassium were studied in twenty patients who underwent open heart surgery in National Medical Center during the period from Jan.1978 to June 1978. There were twelve cases congenital heart disease and eight acquired heart disease. Rigg-Kyvsgaad mark IV roller pump and Polystan bubble oxygenator were used in all patients. Hemodilution was carried out by priming the oxygenator with Hartmann`s solution. Measurements were made of the serum electrolyte, gas analysis and twenty four hour urine electrolytes. During the bypass, the serum potassium decreased Significantly from 4.2?.47 to 3.6?. 72 mEq. per liter. [p<0.05] Fifty seven miliequivalant of potassium chloride were added during operation-urine potassium was higher in the diuretic group than in the non diuretic group. Plasma potassium level in the diuretic group was more significantly reduced than nondiuretic group. In this series large amount of urine potassium loss was noted on the day of operation, the first and second post operative day.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.19 no.2
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• pp.139-142
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• 2016

The coexistence of Wilson disease with Alport syndrome has not previously been reported. The diagnosis of Wilson disease and its ongoing monitoring is challenging when associated with an underlying renal disease such as Alport syndrome. Proteinuria can lead to low ceruloplasmin since it is among serum proteins inappropriately filtered by the damaged glomerulus, and can also lead to increased urinary loss of heavy metals such as zinc and copper. Elevated transaminases may be attributed to dyslipidemia or drug induced hepatotoxicity. The accurate diagnosis of Wilson disease is essential for targeted therapy and improved prognosis. We describe a patient with a diagnosis of Alport syndrome who has had chronic elevation of transaminases eventually diagnosed with Wilson disease based on liver histology and genetics.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2008.04a
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• pp.23-30
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• 2008

Mitochondria biogenesis requires a coordination of two genomes, nuclear DNA (nDNA) and mitochondrial DNA (mtDNA). Disruption of mitochondria function leads to a loss of mitochondrial membrane potential and ATP generating capacity and consequently results in chronic degenerative diseases including insulin resistance, metabolic syndrome and neurodegenerative diseases. Although PPAR-${\gamma}$ coactivator-$1{\alpha}$ (PGC-$1{\alpha}$) was discovered as a central regulator of mitochondria biogenesis and a transcriptional co-activator of nuclear respiratory factor (NRF) and mitochondrial transcription factor A (Tfam), the expressions of PGC-$1{\alpha}$, NRF and Tfam were not significantly altered in tissues showing abnormal mitochondria functions. This observation suggests that there should be another regulator(s) for mitochondria function. Here, we demonstrate microRNAs (miRNAs) can modulate mitochondria function. Overexpression of microRNA dissipated mitochondrial membrane potential and increased ROS production in vitro and in vivo. It will be discussed the target of microRNA and its role in metabolic syndrome.

• Journal of Chest Surgery
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• v.26 no.10
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• pp.749-752
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• 1993

The 26 patients were randomly selected among patients who underwent valve replacement from February 1992 through September 1993 at National Medical Center. They were divided into two groups, one control group[n=13], the other aprotinin group[n=13]. The aprotinin group recieved 15000 KIU/kg aprotinin in the CPB priming volume and 35000 KIU/kg aprotinin intravenously during operation. We checked preoperative and postoperative hemoglobin, platelet, prothrombin time, activated partial thromboplastin time, creatinine phosphokinase and lactic dehydrogenase. There was no difference in the patient`s above clinical parameters between both groups. The platelet count in both groups decreaced after operation. These findings demonstrated that the effectiveness of aprotinin was not associated with platelet number but probably associated with a protection of platelet function and a prevention of hyperfibrinolysis. The intraoperative and postoperative blood loss and requirement of blood were significantly reduced in aprotinin group.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.1
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• pp.54-59
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• 2010

After the advent of B787(Boeing Co.), a civil aircraft using composite materials more than 50% of it total structural weight for weight savings，best performances and efficiencies, various endeavors to develop and apply the state of art of structural health monitoring(SHM) technologies for composite aircraft have been made for many years. Despite their plentiful advantages composite aircraft structures are susceptible to the hidden or barely visible impact damages(BVID) and excessive loads that if unchecked may lead to lower structural integrity, loss of operational performance and finally a sudden catastrophic failure of the aircraft structure. In this paper background of SHM technology and relevant technologies for application of SHM technology to the composite aircraft in the near future and requirements for certification of SHM system are shortly presented.

• Korean Journal of Hydrosciences
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• v.2
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• pp.39-59
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• 1991

Scour at bridge pier is a complicated three-dimensional problem involving interaction of fluld force on movable aid nonuniformily distributed sand grains. Although several analytical solution approaches, experimental research and field investigations for scout at piers have been conducted, no comprehensive and universally acceptable solution is so far available. Even though many methods and equations for predicting scour at piers are available in the literature, hydraulic and/or bridge design engineers are often at a loss over which method or equation is applicable for the specific bridge sites. To provide better understanding about scour phenomena and better predicting of scour at piers, intensive research is conducted through comprehensive review of published literature. Based on the research the state-of-the-art of pier scour prediction for design application is provided as a design guide for practicing engineers in this field. Recommendations for applying aggradation and degradation, contraction scour, and local scour prediction methods or equations are suggested. It is hoped that this paper may provide good information for the prediction of scour at piers.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.7
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• pp.23-32
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• 2004

A spatial simulation model for rural and urban sprawl phenomena was developed with GIS and cellular automata techniques. The model finds out built-up areas invading toward rural areas required for development of existing urban area. Probability of land use change for optimizing the development area was determined using a land suitability analysis method interfaced with GIS methods, based on several criteria in terms of geographic and accessibility factors such as slope of land and distance from city center. Weighting values of the criteria were quantified by an analytic hierarchy process method. For model applicability test, the parameters of criteria were calibrated based on the changes in time series land use data of the test city for 1986, 1996, and 2000, which were classified by remote sensing techniques. Simulated and observed areas in land use maps for city shape of 1996 showed good similarities with each other through a morphology verification method. The model enabled us to evaluate the spatial expansion phenomena of cities considering boundary conditions, and also to simulate land use planning for rural areas in urban fringe.

• Journal of the Korea Furniture Society
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• v.13 no.1
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• pp.27-37
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• 2002

This study was investigated with the surface properties such as physical and accelerated tests of wood-based floorings. In physical test, hardness and abrasion resistance values of laminate floorings were higher than those of others. The center line average surface roughness($R_a$) of imported laminate flooring was highest value($1.34{\mu}m$) and that of imported solid wood flooring was lowest value($0.62{\mu}m$). In cold resistance and moist heat resistance, no defects were found on the surface of all flooring (crack, blistering, peeling, and gloss loss etc.) after testing. Wet-cold-dry cycle test showed that plywood flooring appeared some cracks. In accelerated weathering test, color difference increased with increasing Xenon arc light irradiation

• The Academic Congress of Korean Shoulder and Elbow Society
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• 2002.10a
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• pp.7-7
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• 2002

Historically, the decision to perform a hemiarthroplasty (HHR) versus a total shoulder arthroplasty (TSA) is based on the status of the glenoid and the status of the soft tissues (rotator cuff). In disease processes where the glenoid articular cartilage is relatively well preserved such as avascular necrosis and complex proximal humerus fractures, most orthopaedists recommend performing a HHR while preserving the native glenoid articular surface. At the other end of the spectrum, if the glenoid has excessive bone loss or is unreconstructible, a HHR is the preferred procedure. In patients who have deficient so(t-tissues (rotator cuff) such as rotator cuff tear arthropathy and, occasionally, rheumatoid arthritis, a HHR is the procedure of choice. The indications for HHR in osteoarthritis remain somewhat controversial. There is mounting evidence that performing a HHR for osteoarthritis is inferior to TSA. Recent developments, or 'third generation techniques and materials', in shoulder arthroplasty are expected to improve the longevity of TSA, particularly the glenoid component. In addition, newer designs of reverse-ball prostheses are entering the market with promising early results in patients with deficient rotator cuff mechanisms.