• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.19-19
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• 2016

오늘날, 보다 정밀한 대기기상 분석과 정확한 기상 예측을 위해 보편적으로 기상레이더를 활용하고 있다. 지표면과 가까운 저층에서 주로 발생하는 국지성 호우 및 돌발기상에 대한 대응을 위해서는 기상레이더 역시 저층 관측이 수반되어야 한다. 하지만, 국토 대부분이 산악지형으로 이루어진 우리나라에서는 산악지형에 의한 지형클러터와 빔 차폐의 영향을 피하여 원만한 기상관측을 위해 대부분의 기상레이더가 고지대에 설치, 운영되고 있다. 그럼에도 불구하고 낮은 고도각의 레이더 관측 자료에서는 여전히 지형 클러터 및 차폐에 따른 영향으로 인해 자료 품질의 신뢰성이 떨어질 수 밖에 없다. 현재 클러터나 차폐가 발생한 영역에 대해 상위 고도각의 자료를 이용하는 등의 방법으로 보정을 수행하고 있지만 각 고도각 관측 자료들의 시간적 차이가 발생함에 따라 부정확성이 발생할 수 있다는 단점이 있다. 따라서 본 논문에서는 차폐 영역 보정에 대한 처리를 위해 단일 관측자료 만을 이용하는 방법을 적용함으로서 시간적 불일치성에 대한 문제를 해결하고, 초단기 강수예측을 위한 강수에코의 정확한 추적을 위해 레이더 영상에 적응적인 차폐, 클러터 보정 기법을 제안한다. 제안 기법은 강수에코의 형태학적 구조에 기반한 차폐보정을 위해 영상 처리 기법의 한 종류인 모폴로지 기법을 적용함으로써 강수에코의 모양, 크기, 및 구조에 따라 침식 및 팽창 과정을 수행하여 클러터나 차폐로 인해 소실된 강수에코 영역을 보정한다. 실험결과 레이더 강수추정의 정확성 향상을 꾀할 수 있었으며, 강수 추적을 위한 강수에코의 형태학적 복원이 가능함을 확인하였다. 이로부터, 향후 저층관측 레이더 자료의 활용성 증대와 에코 형태에 기반한 강수 추적 알고리즘 개발 및 성능 향상에 활용될 수 있을 것으로 기대한다.

• Korean Journal of Ichthyology
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• v.12 no.4
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• pp.244-249
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• 2000

This study was conducted to obtain data for identification of species among elvers of anguillids, Anguilla japonica and A. anguilla and A. rostrata implanted in Korea for culture. The longer predorsal length and the fewer number of vertebrae distinguished elvers of A. rostracta from those of A. anguilla and A. japonica. A. japonica and A. anguilla were well discriminated each other in the statistical value of preanal length which the former showed shorter distance. It was remarked phylogenetically that the morphological changes according to growth in head and predorsal length of A. rostrata was different from other two species. So the elvers of A. japonica, A. anguilla and A. rostrata culturing in Korea can be distinguished by the vertebral counts, predorsal and preanal length.

• Journal of Applied Biological Chemistry
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• v.55 no.2
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• pp.109-115
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• 2012

The aim of this study was to determine hepatoprotective effects of pig placenta hydrolysates (PLA) on liver damage-induced rats. Sprague Dawley rats were subcutaneously injected with carbon tetrachlorides and divided into 4 groups: negative control (DMSO treated), two PLA treated groups, low dosage of PLA (LPLA; 300 mg/kg body weight) and high dosage of PLA (HPLA; 1000 mg/kg body weight), and silymarin treated group (80 mg/kg body weight). Rats in each group orally received assigned compounds for 3 weeks. For the normal control group vehicle (corn oil) was injected. After 3 weeks, liver and spleen weights were greater in the two PLA and silymarin groups than the negative control group. After bromosulfalein (BSP) treatment, the clearance rates were in the descending order of negative control > LPLA > HPLA = silymarin and serum BSP levels exhibited the opposite trends of the clearance rates. Serum levels of aspartate aminotransferase, alanine aminotransferase, triglyceride, and cholesterol lowered with PLA in a dose-dependent manner. The decrease with HPLA was similar to that with silymarin. In addition, triglyceride, cholesterol, lipid peroxides levels in the liver decreased in HPLA and silymarin compared to the negative control. The liver morphometry was improved in HPLA- or silymarin-treated rats in comparison to the negative control. In conclusion, HPLA administration ameliorated the hepatotoxicity as much as silymarin in rats injected with carbon tetrachlorides.

• Journal of Veterinary Clinics
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• v.27 no.5
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• pp.533-539
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• 2010

Stem cell-based therapy is under intensive investigation to treat acute renal failure (ARF). The purpose of this study was to evaluate available ARF models, and suggest a model appropriate to therapeutic evaluation of the stem cells in preclinical approach by determining the optimum concentration of nephrotoxic agents and duration of ischemia induction. Three different types of available acute kidney injury (AKI) animal models were analyzed using rats: Cisplatin (saline, 5 and 7.5 mg/kg, IP) or glycerol (saline, 8 and 10 ml/kg, IM)-induced nephrotoxicity as toxic models and ischemia-induced (sham, 35 and 45 minutes) nephropathy as an ischemic model. The relevance and applicability to investigate especially the regenerative ability of stem cells were evaluated regarding morphology, renal function and survival at this time point. In the point of renal function, 10 ml glycerol/kg and 7.5 mg cisplatin/kg model in toxic models and 45 min model in ischemia models showed significant decrease for the longer observation time compared to 8 ml glycerol/kg, 5 mg cisplatin/kg and the 35 min ischemia models, respectively. All groups were observed no mortality except 45 min-ischemia model with 50% survival. Histological significant alterations including cast formation in the tubular lumen, tubular necrosis and apoptosis were revealed on the second day in either ischemiaor glycerol-induced models, and on day 5 in cisplatin-induced models. The results indicate that ischemia 35 min-, cisplatin 7.5 mg/kg- and glycerol 10 ml/kg-induced AKI would be ideal animal models to monitor a outcome parameter related to the therapeutic effects on renal function with noninvasive techniques in the same animal at multiple time points. Our findings also suggest that the best time points for the functional or histological interpretation of renal will be on day 2 in both glycerol- and ischemia-induced AKI models and on day 5 in cisplatin-induced AKI.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.256-262
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• 2016

A cyber crime has been evolving, as other crimes have. Beyond physical damages such as financial crimes in the cyber world, it has evolved into psychological forms like cyber-bullying. In today's crimes, measures that consider psychological effects of crimes are highly regarded in that fear of crime is considered as well as visible crimes. Accordingly, cyber bullying, which causes psychological damages, needs to be treated very importantly. Because the characteristics of cyber crime is caused by different circumstances from the real world, measures should be taken in different aspects. Rather than physical damages, which can be found in the conventional crimes, cyber crimes cause psychological damages, so the effect that has on inflicting should be specified. Especially, in the environment that virtual reality is ubiquitous through smart phones, it is very difficult to establish measures by considering all the causes of general cyber crimes. Therefore, this study estimated what affects cyber bullying by focusing on personalized faith factor among social bond theory, which can control cyber crimes. As a result, self-controling faith was verified to have a negative effect on cyber bullying, so faith is a very important factor in personalized environment. Thus, it is suggested that the characteristics of cyber space and education of humanism, which can affect individuals' faith should be emphasized.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1337-1342
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• 2008

This study was conducted to investigate effects of chemical sanitizers on inhibiting foodborne pathogens, such as Listeria monocytogenes (L. monocytogenes), Salmonella Typhimurium (S. Typhimurium), and E scherichia coli O157:H7 (E. coli O157:H7), on cabbages. Cabbages were inoculated with the culture cocktail of pathogens and treated with water, 100 ppm commercial chlorine, and 50, 100, and 200 ppm chlorine dioxide ($ClO_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Treatments with water did not significantly reduce levels of three pathogens whereas other treatments with chemical sanitizers significantly reduced levels of three pathogens. Treatment with 200 ppm $ClO_2$ for 10 min was the most effective at inhibiting pathogens and reduction levels were 1.90, 1.92, and 1.98 log CFU/g for L. monocytogens, S. Typhimurium, and E. coli O157:H7, respectively. Levels of reduction were increased with the increase of $ClO_2$ concentrations. When chemically injured cells were investigated, there were no significant differences on the levels of injured cells between before and after treatment with commercial chlorine and $ClO_2$. These results suggest that $ClO_2$ can be used as an alternative sanitizer for reducing pathogens on fresh produces.

• Tunnel and Underground Space
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• v.17 no.5
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• pp.372-380
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• 2007

Surface damage due to subsidence is an inevitable consequence of underground mining, which may be immediate or delayed for many years. The surface damage due to abandoned underground mine is observed to be two subsidence types such as simple sinkhole or trough formation to a large scale sliding of the ground from with in the subsided area. An evaluation of the risk of a subsidence occurrence is vital in the areas affected by mining subsidence. For a subsidence prediction or a risk evaluation, there has been used various methods using empirical models, profile functions, influence functions and numerical models. In this study, a simple but efficient evaluation method of subsidence hazard is suggested, which is based on a diffusion theory and uses just information about geometry of caving and topography. The diffusion model has an analogous relationship with granular model which can explain a mechanism of subsidence. The diffusion model is applied for the evaluation of subsidence hazard in abandoned metal and coal mines. The model is found to be a simple but efficient tool because it needs information of geometry of caving and gangway and the topography.

• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.686-693
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• 2007

Purpose : Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), is a potent inhibitor of inosine-monophosphate dehydrogenase (IMPDH), a new immunosuppressive drug used. It was reported that MPA protected neurons after excitotoxic injury, induced apoptosis in microglial cells. However, the effects of MPA on hypoxic-ischemic (HI) brain injury has not been yet evaluated. Therefore, we examined whether MPA could be neuroprotective in perinatal HI brain injury using Rice-Vannucci model (in vivo) and in rat brain cortical cell culture induced by hypoxia (in vitro). Methods : Cortical cells were cultured using a 18-day-pregnant Sprague-Dawley (SD) rats and incubated in 1% $O_2$ incubator for hypoxia. MPA ($10{\mu}g/mL$) before or after a HI insult was treated. Seven-day-old SD rat pups were subjected to left carotid occlusion followed by 2 hours of hypoxic exposure (8% $O_2$). MPA (10 mg/kg) before or after a HI insult were administrated intraperitoneally. Apoptosis was measured using western blot and real-time PCR for Bcl-2, Bax, caspase-3. Results : H&E stain revealed increased brain volume in the MPA-treated group in vivo animal model of neonatal HI brain injury. Western blot and real-time PCR showed the expression of caspase-3 and Bax/Bcl-2 were decreased in the MPA-treated group In in vitro and in vivo model of perinatal HI brain injury, Conclusion : These results may suggest that the administration of MPA before HI insult could significantly protect against perinatal HI brain injury via anti-apoptotic mechanisms, which offers the possibility of MPA application for the treatment of neonatal HI encephalopathy.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.142-149
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• 2009

Purpose: We wanted to assess the radiological and clinical results and the prognostic factors after an operation for capitellar fractures associated with/without other injury around the elbow. Materials and Methods: Among the 25 patients (mean age: 49 years-old) who underwent open reduction and internal fixation for capitellar fractures, there were nineteen type 1 fractures and six type 3 fractures. The mean follow up period was 14.8 months. We assessed the factors affecting the radiological and functional results, such as the fracture pattern, the patient age and the surgical approaches. Results: In 24 of 25 patients, bony union was achieved at postoperative 1 year. There were eighteen excellent, four good, two fair and one poor functional results according to the Broberg and Morrey elbow score. The most common type was type 1 and the most common associated injury was lateral condylar fracture. The patients with type 1 fracture rather than the patients with type 3 fracture and the patients who had an extraarticular associated fracture rather than an intraarticular associated fracture had better clinical outcomes. Conclusion: 22 (88%) of the patients were satisfied at the result. The type of capitellar fracture and an associated intraarticular elbow fracture were shown to be important prognostic factors in this study.

• Tuberculosis and Respiratory Diseases
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• v.42 no.2
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• pp.184-205
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• 1995

Background: Pulmonary toxicity by bleomycin has multiple mechanisms including direct tissue toxicity due to oxygen-derived free radicals and indirect toxicity through amplification of pulmonary inflammation. To evaluate the effect of chelators or free radical scavenger to lung damage induced by bleomycin, penicillamine as a copper chelator, deferoxamine as an iron chelator and vitamin E as a free radical scavenger were administered. Methods: Two hundred Wistar rats were divided into five groups: Control, bleomycin treated, bleomycin-penicillamine treated, bleomycin-deferoxamine treated, and bleomycin-vitamin E treated groups. Rats sacrificed on day 1, day 3, day 4, day 7, day 14, and day 28 after treatment. Bronchoalveolar lavage, light microscopic and immunohistologic studies for type I, III, IV collagens, fibronectin, laminin and NBD phallicidin were evaluated. Results: There was a significant increase in the total cell counts of bronchoalveolar lavage on day 1 from all treated animals and vitamin treated group showed an abrupt decrease in total cell counts with decrease of neutrophils on day 3. Bleomycin-vitamin E treated group had the least histologic changes such as pulmonary fibrosis. The alveolar basement membranes were positive for type IV collegen and laminin. Basement membranes of bleomycin, bleomycin-penicillamine, or bleomycin-deferoxamine treated groups were disrupted and fragmented on day 4 or 7. The bleomycin-vitamin E treated group had intact basement membranes until day 28. Conclusion: Bleomycin-induced pulmonary fibrosis was related to the severity of acute injury to oxygen radicals or activation of neutrophils and disruption of basement membrane. Vitamin E seemed to be the most effective antioxidant in the inhibition of bleomycin-induced pulmonary injury and fibrosis.