• 한국수자원학회논문집
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• 제34권1호
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• pp.91-103
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• 2001

본 연구에서는 지표면유출과 하천유출의 실시간 연계를 통하여 하천 각 구간에서의 수위와 유량을 예측하는 수리학적 홍수추적 모형을 개발하였다. 주로 유역의 지형특성에 따라 결정되는 수문곡선의 형상을 반영하여 홍수 유출량 산정방법을 개선하였으며, 침투과정을 고려하여 강우초가 첨두유량의 과다산정을 제거하였다. 지표면유출의 하천유입을 연속방정식에 반영하여 여러 단면에서의 유입이 용이하였으며, 이는 강우의 급격한 변이에서도 수치적 안정을 가져다 주었다. 폭우시 양양 남대천 유역에서 현장 관측을 실시하였으며, 관측자료에 적용하여 개발된 모형의 현장 적용성과 신뢰성을 확보하였다.

• Water Engineering Research
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• 제6권4호
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• pp.179-187
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• 2005

This paper introduces the Cheonggye-cheon restoration project. The restoration project aims to revive the 600-year-old city of Seoul by recovering the historical heritage, guaranteeing safety from the deteriorated covering structures, creating the environment-friendly space, and revitalizing the neglected city centers. In order to understand the current hydrological cycle of the Chenggye-cheon watershed, the annual water balance of the region was calculated using the observed data including precipitation, runoff, water supply and sewage, and the changes in the groundwater level. The $2001{\sim}2002$ data were used to calibrate the WEP, and the $2003{\sim}2004$ data were used to verify the WEP. The calibration and validation results for the flood hydrograph how a reasonable value (at Majanggyo station, the R2 for the calibration period was 0.9, and that for the validation period was 0.7). According to the annual water balance of the Cheonggye-cheon watershed for 2004, the amount of surface runoff, infiltration, and evapotranspiration was 1,097mm, 216mm and 382mm, respectively, for an annual precipitation of 1,499mm. The application results from WEP, a distributed hydrological model, provide more detailed information of the watershed, and the model will be useful for improving the hydrological cycle in urban watershed.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.99-105
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• 2001

The purpose of this study is to investigate the effects of pending depth treatment on water balance in paddy fields. The pending depth treatments were very shallow, shallow and deep. The experimental plots were three $80m{\times}25m$ rectangular plots. Daily values of rainfall amount, pending depth, irrigation water, drainage water, evapotranspiration, infiltration, and piezometeric head were measured in the field. The pending depth was continuously observered by water level logger during the growing season. The ET was measured in 1m diameter PVC lysimeters. Irrigation water volume was measured by 75m pipe flow meter and the drainage water volume was measured by 25mm and 75mm pipe flow meters and a recording Parshall fulume. PVC pipe piezometers with 12mm diameter were used. The results of the water balance showed that irrigation water of 881.1mm, 735.4mm, and 532.6mm in very shallow, shallow, and deep pending, respectively. The effective rainfall was 182.6mm(44.6%), 254.7mm(62.2%), and 188.6mm(46.0%) in very shallow, shallow, and deep pending, respectively. The results show that the shallow pending depth looks the best of the three treatments.

• 한국대기환경학회지
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• 제24권3호
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• pp.321-328
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• 2008

The number of patient with allergic asthma and atopy have increased in the cities of Korea steadily. In order to elucidate the primary factor, we investigated whether the house dust particles collected from an apartment of the middle classes has promoting effects of allergen-related airway inflammation and airway hyperresponsiveness. Mice were treated with 0.1 mL of 1 mg/mL of house dust particles suspension by intratracheal instillation once weekly for 10 weeks combined with ovalalbumin (OVA) sensitization. Intratracheal instillation of house dust particles and OVA sensitization caused an increase in the level of serum L-lactate dehydrogenase (LDH), immunoglobulun-E (IgE) and histamine, and an elevation in respiratory resistance. It also enhanced infiltration of eosinophils in the bronchoalveolar lavage fluid (BALF) of mice, IgE and eotaxin expression in blood, and T helper type 2 cell derived cytokine levels such as of interleukin (IL)-4, IL-13 and IL-5 in the BALF. However, it did not influence T helper type 1 cytokine such as interferon-gamma in the BALF. These results indicate that house dust particles elevate allergen-related airway inflammation and airway hyperresponsiveness in mice and may play an important role in the aggravation of asthma and atopy in Korea.

• Environmental Analysis Health and Toxicology
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• 제25권2호
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• pp.121-129
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• 2010

This study was carried out to investigate whether asian yellow sand dust (AS) has promoting effects of allergen-related airway inflammation and airway hyperresponsiveness, because the number of patient with allergic asthma and atopy, and with chronic bronchial inflammation and pneumonia have increased steadily in the cities of Korea. The appearance of AS collected was all round and flat, and the diameter was mostly below about 5 ${\mu}m$. When mice were treated with AS suspension by intratracheal instillation combined with ovalalbumin(OVA) sensitization chronically, the level of serum L-lactate dehydrogenase (LDH), IgE and histamine, and respiratory resistance was increased. Intratracheal instillation of AS and OVA also enhanced infiltration of eosinophils in the bronchoalveolar lavage fluid (BALF), IgE and eotaxin expression, and T helper type 2 cell derived cytokines of interleukin (IL)-4, IL-13 and IL-5 as major contributors to allergy and asthma. These results indicate that AS elevates allergen-related airway inflammation and airway hyperresponsiveness in mice and may play an important role in the aggravation of respiratory diseases in Korea.

• 대한수의학회지
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• 제16권1호
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• pp.97-103
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• 1976

In order to clarify the histopathological changes resulting from nitrate poisoning, rabbits were experimentally poisoned by the oral administration of $KNO_3$ or $NaNO_2$ and examined clinically and histopathologically. In addition, the quantitative changes of glycogen level in hepatic cells were histochemically observed. The results obtained were summarized as follows: 1. Clinical symptoms observed from the acute cases which died within 2 hours after the administration were severe cyanosis of visible mucosa, frequent urination, and dyspnea. However, in chronic cases administrated daily with $KNO_3$ for 43, 50 and 74 days respectively, no marked symptoms were observed. 2. Macroscopic changes observed in acute cases were severe methemoglobinemia, cloudy swelling of hepatic cells, hemorrhage and hyperemia of gastric mucosa, and hyperemia of other organs. In chronic cases there were marked hyperemia, dark-red coloring and increasing of consistency in liver and kidney, and swelling of spleen. 3. Microscopic changes observed in acute cases were hemorrhage and hyperemia of various organs, cloudy swelling and centrilobular necrosis of hepatic cells and necrosis of convoluted tubular epithelium in kidney. In chronic cases there were round cell infiltration of the interlobular connective tissue and epithelial proliferation of interlobular bile ducts in the liver, and necrosis of the convoluted tubular epithelium and proliferation of interstitial connective tissue in kidney, thickening of alveolar septa of lungs, activated hemopoiesis of bone marrow, and myeloid metaplasia of sqlenic pulp. 4. Glycogen storage in liver cells was decreased in acute cases, on the contrary, increased in chronic cases.

• IMMUNE NETWORK
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• 제14권5호
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• pp.249-254
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• 2014

Allergic asthma is a chronic pulmonary inflammatory disease characterized by reversible airway obstruction, hyperresponsiveness and eosinophils infiltration. Toll-like receptors (TLRs) signaling are closely associated with asthma and have emerged as a novel therapeutic target in allergic disease. The functions of TLR3 and TLR4 in allergic airway inflammation have been studied; however, the precise role of TIR-domain-containing adapter-inducing interferon-${\beta}$ (TRIF), the adaptor molecule for both TLR3 and TLR4, is not yet fully understood. To investigate this, we developed a mouse model of OVA-induced allergic airway inflammation and compared the severity of allergic airway inflammation in WT and $TRIF^-/^-$ mice. Histopathological assessment revealed that the severity of inflammation in airway inflammation in TRIF-deficient mice was comparable to that in WT mice. The total number of cells recovered from bronchoalveolar lavage fluid did not differ between WT and TRIF-deficient mice. Moreover, TRIF deficiency did not affect Th1 and Th2 cytokine production in lung tissue nor the level of serum OVA-specific IgE, $IgG_1$ and $IgG_{2c}$. These findings suggest that TRIF-mediated signaling may not be critical for the development of allergic airway inflammation.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.970-979
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• 2006

Construction of underground structure requires higher standard of planning and design specifications than in surface construction. However, high construction cost and difficult working environment limit design level and construction quality. One of the most sensitive factors to be considered are infiltration and external pore-water pressures. Development of pore-water pressure may accelerate leakage and cause deterioration of the lining. In this paper, the development of pore-water pressure and its potential effect on the linings are investigated using physical model tests. A simple physical equipment model with well-defined hydraulic boundary conditions was devised. The deterioration procedure was simulated by controlling both the permeability of filters and flowrate. Development of pore-water pressure was monitored on the lining using pore pressure measurement cells. Test results identified the mechanim of pore-water pressure development on the tunnel lining which is the effect of deterioration of drainage system. The laboratory tests were simulated using coupled numerical method, and shown that the deterioration mechanism can be reproduced using coupled numerical modelling method.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.271-271
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• 2010

$BaTiO_3$(BT) has high permittivity so that has been applied to dielectric and insulator materials in 3D system-level package integration. In order to achieve excellent performance of device, the BT layer should be highly dense. In this study, BT thick films were prepared by the inkjet printing method. And these films were cured at $280^{\circ}C$ after infiltration of polymer resin. As a result, we have successfully fabricated not only the inkjet-printed hybrid BT film but also metal-insulator-metal(MIM) capacitor without sintering process. Changes in the dielectric constant of BT hybrid film with particle size and packing density were investigated. The dielectric constant was increased with increasing packing density and particle size. Further, the BT hybrid film using two different size particles had even higher packing density and dielectric constant.

• 대한의생명과학회지
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• 제10권4호
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• pp.447-452
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• 2004

This study was designed to investigate the effect of Codonopsis lanceolata extracts on carbon tetrachloride (CCl₄)­induced hepatotoxicity in rats fed high, medium or low fat diet. The liver weight was increased not by the level of fat in diet but by administration of CCl₄. Activities of serum aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were significantly increased by CCl₄, the activities of AST and alanine aminotransferase (ALT) were significantly decreased in case of CCl₄ treatment with C. lanceolata extracts. In high fat diet with CCl₄ administration, the content of total lipid in liver was significantly increased, which was significantly decreased by the administration of C. lanceolata extracts. Administration of C. lanceolata water extracts remarkably prevented the tissue injury such as lipid degeneration, infiltration of inflanunatory cells and necrosis caused by CCl₄, but those methanol extracts did not affect histopathological changes of the liver as water extract. The data suggest that intake of C. lanceolata extracts would prevent lipid accumulation and hepatotoxicity induced by high fat diet and CCl₄ abministratim, and the water extract of C. lanceolata is supposed to be more effective than those methanol extract.