Background : ROS produced by oxidative stress damaged endothelial cells, and cause a variety of vascular complications. In diabetic hyperglycemia state, ROS increase. The polyol pathway occur in diabetic complications, the excess glucose is absorbed into the polyol pathway when aldose reductase increased, NADPH changes it to sorbitol. Glutathione (GSH) removes ROS. GSH level is reduced by glutathione reductase, using NADPH as an electron donor. Activation of the polyol pathway decrease NADPH, and GSH also reduced. As a result, ROS is increased. In diabetic hyperglycemia state, Glycolysis increases. Effects of increased glycolysis, protein kinase C (PKC) is increased. NAD(P)H oxidase, stimulated by PKC-dependent pathway, increases ROS in the cell. In this study, we measured the ROS scavenging activity of 5 natural products (Lycii fructus, Astragalus membranaceus, Cassia Tora, Polygonatum odoratum, Rubus Coreanus), to confirm the efficacy as diabetic antioxidants. Methods and Results : We extracted 5 natural product by distilled water and ethanol. DPPH radical scavenging activity was significantly higher in Lycii fructus, Rubus coreanus. ABTS radical scavenging activity was better Rubus coreanus, Lycii fructus, Cassia Tora. In addition to, Rubus coreanus, Cassia Tora, Lycii fructus was comparatively higher reducing power activity than other natural products. And total phenolic and flavonoid contents were much higher in Rubus coreanus compared with other extracts. Conclusion : These results suggest that Lycii fructus, Rubus coreanus can be applied as diabetic antioxidant that prevent vascular complications caused by ROS.

Background : Dioscorea quinqueloba(DQ) is a medicinal herb that is used as an alternative therapy for cardiovascular disease and various medical conditions. The objective of this study was to characterize the antioxidant activities of DQ. Methods and Results : The samples were extracted with Distilled water and analyzed for total flavonoid contents, polyphenol contents, DPPH radical scavenging activity, and ABTS radical scavenging activity. H9c2 cardiomyoblast cells were subjected to H2O2, to study the protective effect of DQ on cell viability, and ROS production. The total amounts of polyphenols and flavonoids, which indicate the antioxidant capabillity of water extracts from DQ were 27.21mg/g and 22.95mg/g, respectively. The DQ water extract showed highest antioxidant activity by DPPH and ABTS scavenging activities. The DQ water extract was protected cells against H₂O₂-induced cell death without any cytotoxicity, as determined by the MTT assay. The DQ water extract also was inhibiting production of intracellular ROS. Conclusion : These observations suggest that DQ can use potentially good natural antioxidant in daily life for possible health benefits.

Background : Osteoclasts as multinucleated cells originate from hematopoietic monocyte/ macrophage precursor cell, shows the bone absorption through the commitment, differentiation, fusion, and bone resorption stages by regulation of M-CSF and RANKL. It has been reported a significant negative correlation between the increase of oxidative stress and the bone density, and when RANKL reaction to the osteoclasts precursor cells is mainly generated ROS is due to increased activity of NADPH oxidase1 (NOX1), and these ROS act as a factor which promotes osteoclasts differentiation. Thus, RANKL signaling process is important that excessive osteoclast formation and differentiation inhibited through the regulation of each step. Methods and Results : F3570 ethanol extract showed relatively high activity at in-vitro antioxidant activity. F3570 water extract inhibited ROS generation in RAW 264.7 cells stimulated with H2O2 and RANKL, even at low concentrations. The inhibitory effect of osteoclast differentiation on F3570 water extract was confirmed that shown through NF-κB pathway, MAPK pathway including ERK and JNK. F3570 ethanol extract is considered to be regulated by the p38 MAPK and the other signaling pathway. Also, F3570 both water and ethanol extract were significantly reduced gene expression such as TRAP, calcitonin receptors and integrin β3 of RANKL-induced mature osteoclast in the bone resorption stage. Conclusion : Through this study, F3570 extract revealed an outstanding inhibitory effect and signaling mechanisms in osteoclast differentiation induced by RANKL. These results suggest that F3570 is bone diseases associated with aging or osteoporosis caused by menopause in an aging society is expected to be a superior candidate for the treatment or the prevention

홍차 분말의 첨가량을 0~8%로 달리하여 제조한 스펀지 케이크의 물리·화학적 품질, 항산화 활성 및 소비자 기호도 를 비교하였다. 케이크의 pH와 높이는 홍차 분말의 첨가량 이 증가할수록 유의적으로 감소하였으며(p<0.05), 굽기 손 실률의 경우 홍차 분말의 함량이 증가함에 따라 유의적으로 증가하였다(p<0.05). 경도는 0~4% 시료 간에서는 유의적인 차이는 없었다(p>0.05). 한편 명도(L*)는 붉은색을 띄는 홍 차 분말 고유색의 영향으로 첨가량이 증가할수록 유의적으 로 감소하였고(p<0.05), 적색도(a*)와 유의적으로 증가하였 다. 황색도(b*)의 경우 증가하는 경향을 보였으나, 0~4%, 6~8% 시료 간에 유의적인 차이는 발견되지 않았다 (p>0.05). 항산화 활성을 나타내는 전자공여능과 ABTS 라 디칼 소거능 활성은 홍차분말을 첨가할수록 유의적으로 증가하는 경향이 나타났다(p<0.05). 소비자 기호도 결과 2~4% 첨가군이 색과 부드러움을 제외한 나머지 항목에서 대조군보다 높게 평가되었으며, 따라서 관능품질과 건강기 능성 효과 등을 고려할 때 소비자의 기호를 충족시키기 위한 최적 첨가비율은 2~4%가 가장 적합한 것으로 판단된 다.

This study analyzed fluctuations of ground water level of ground water wells developed in Seongsan watershed of Jeju Island until 2013 using MODFLOW, a numerical analysis model. Ground water level shows greater fluctuations from increase of pump capacity compared to the number of ground water wells. The development of ground water at the top of watershed was found to have direct influence on ground water level. Ground water wells developed until 2013 were used to continue pumping for 50 days, and ground water level of coastal region was reduced below 50% compared to the standard water level. In addition, the range of fluctuation of water level was large in the east coast region, which represents the direction of flow of ground water.

Jeju Island is the highest rain-prone area in Korea that possesses affluent water resources, but future climate changes are predicted to further increase vulnerabilities as resultant of increasing of extreme events and creating spatial-temporal imbalance in water resources. Therefore, this study aimed to provide basic information to establish a proper water resources management plan by evaluating the effects of climate change on water resources using climate change scenario. Direct runoff ratio for 15 years (2000~2014) was analyzed to be 11∼32% (average of 23%), and average direct runoff ratio for the next 86 years (2015∼2100) was found as 28%, showing an increase of about 22% compared to the present average direct runoff ratio (23%). To assess the effects of climate change on long-term runoff, monthly runoff variation of future Gangjeong watershed was analyzed by dividing three time periods as follows: Present (2000∼2030), Future 1 (2031∼2070) and Future 2 (2071∼ 2100). The estimated results showed that average monthly runoff increases in the future and the highest runoff is shown by Future 2. Extreme values has been expected to occur more frequently in the future as compared to the present.

In this study a hybrid energy dissipation device is developed by combining a steel slit damper and linear-slot friction dampers to be used for seismic retrofit of structures. The hybrid damper has an advantage in that friction dampers are activated for small earthquakes or strong wind while slit damper remains elastic, and both friction and slit dampers work simultaneously for strong earthquakes. Cyclic loading tests of the linear-slot friction, slit, and the combined hybrid dampers are carried out to evaluate their seismic energy dissipation capability.

A number of projects for development have been done continuously due to the increase of tourist in Jeju Island. However flood disaster countermeasure due to urbanization is not considered during this development projects. This study is to make basic process for the flood estimation in Han stream of Jeju Island. The variation of stream discharge due the every 5 years' land use change from 1980 to 2005. Data for flood events (rainfall and discharge) were collected for HEC-HMS model. Clark method was used for unit hydrograph analysis. For the estimation of Clark unit hydrograph parameters, Kraven II and Sabol’s empirical equations were applied. The peak discharge increased 9.9~33.67% and total discharge amount increased 12.53~30.21%. Also, time of concentration for peak discharge was reduced by 10 minutes for each event.

Rainfall-runoff model of Jeju Oedo Stream was used to compute the optimal unit hydrograph by HEC-HMS model that reflecting on watershed characteristics. Each rainfall event was comparatively analyzed with the actual flow measurement using Clark, Snyder and SCS synthetic methods for derived unit hydrograph. Subsequently, the null hypothesis was established as p-value for peak flow and peak time of each unit hydrograph by one-way ANOVA(Analysis of variance) was larger than significance level of 0.05. There was no significant difference in peak flow and peak time between different methods of unit hydrograph. As a result of comparing error rate with actual flow measurement data, Clark synthetic unit graph best reflected in Oedo Stream as compared to other methods, and error rate of Clark unit hydrograph was 0.02~1.93% and error rate at peak time was 0∼2.74%.

As occurrence of gradually increasing extreme temperature events in Jeju Island, a hybrid downscaling technique that simultaneously applies by dynamical method and statistical method has implemented on design rainfall in order to reduce flood damages from severe storms and typhoons.As a result of computation, Case 1 shows a strong tendency to excessively compute rainfall, which is continuously increasing. While Case 2 showed similar trend as Case 1, low design rainfall has computed by rainfall in A1B scenario. Based on the design rainfall computation method mainly used in Preventive Disaster System through Pre-disaster Effect Examination System and Basic Plan for River of Jeju Island which are considering climatic change for selecting 50-year and 100-year frequencies. Case 3 selecting for Jeju rain gage station and Case 1 for Seogwipo rain gage station. The results were different for each rain gage station because of difference in rainfall characteristics according to recent climatic change, and the risk of currently known design rainfall can be increased in near future.

In the mountain streams in Jeju Island, strong turbulence and roughness usually made it nearly impossible to utilize most of intrusive instrumentation for streamflow discharge measurements. Instead, a non-intrusive fixed electro-magnetic wave surface velocimetry (fixed EWSV: Kalesto) became alternatively popular in many representative streams to measure stream discharge seamlessly. Currently, Kalesto has shown noteworthy performance with little loss in flood discharge measurements and also has successfully provided discharge for every minute. However, Kalesto has been operated to regard its measured one-point velocity as the representative mean velocity for the given cross-section. Therefore, it could be highly possible to potentially encompass discharge measurements errors. In this study, we analyzed the difference between such Kalesto discharge measurements and other alternative concurrent discharge measurements such as Acoustic Doppler Current Profiler (ADCP) and mobile EWSV which were able to measure velocity in multi-points in the cross-section. Consequently, Kalesto discharge deviated from ADCP discharge in amount of 48% for relatively low flow, and more than 20% difference for high flow compared with mobile EWSV discharge measurements. These results indicated that the one-point velocity measured by Kalesto should be used as a cross-sectional mean velocity, rather it should be accounted for as an index-velocity in conjunction with directly measured cross-sectional mean velocity by using more reliable instrumentations. After inducing Kalesto Discharge Correction Coefficient (KDCC) that actually means relationship between index velocity and cross-sectional mean velocity, the corrected discharge from Kalesto was significantly improved. Therefore, we found that index velocity method should be applied to obtain better accuracy of discharge measurement in case of Kalesto operation.

최근 몇 년간 발생한 대형 화재사고의 경우 특수구조물에 대한 화재가 많으며 화재의 피해가 커진 경우 공통적으로 초기 진압에 어려움이 있었고, 적절한 방재작업을 수행할 장비의 부재가 원인으로 분석된 사례가 많았다. 이와 같은 특수구조물의 화재에 있어서 화재 진압을 위한 접근성이 용이하고 외부에서 화원으로 직접 방수 할 수 있는 기능을 갖춘 특수 방재장비의 도입 및 기술개발의 요구가 컸다. 이에 따라 우리나라의 산업형태에 따른 도시구조, 건축구조 등에 적합하고 기존의 유사 외국 기술이 갖고 있는 기술적 한계점을 극복한 “한국형 원격조정 파괴방수차”를 개발이 요구되었다. 본 연구에서는 목조건물, 문화재, 샌드위치 판넬 구조의 공장 및 창고, 컨테이너 Box, 항공기, 철도차량 등 특수목적 구조물의 화재 발생시 구조물의 외부를 국소파괴하고 내부로 방수노즐을 삽입 후 다량의 물 또는 폼 소화액을 방수하여 효과적인 초기 진압을 수행할 수 있는 소방장비에 대해 원격조정 굴절 붐 구조를 갖는 파괴방수차량의 국산화 설계기술, 제조기술, 하이브리드 타입 파괴방수 모듈의 설계/제작을 통한 굴절 붐 방수탑 통합 기술에 대해 연구하였다. 또한, IT기술을 접목한 노즐 모듈의 자동이송 및 아웃트리거 자동 셋팅 시스템 기술과 설계의 전 과정에 걸쳐 수치해석을 통한 설계검증 기술 그리고 시제품에 대해 자체 평가기준에 따른 성능평가에 대해 연구하였다.

The water resources system of Jeju-do Island entirely depends on groundwater. This study is making a precision observation of baseflow, surface water, water shortage that might be vulnerable to climate change and drought in future. The field observation of baseflow discharges in Akgeuncheon stream has regularly been made with ADCP and ADC and Flowmate every two weeks for twenty-two (22) months (July 8, 2011 to April 27, 2013). This paper represent the results of calculating discharge of a number of hydraulic structures (broad-crested weirs) with comparing and has been calculated more accurate discharges with suitability of different observation methods. The average discharge has been observed 0.851 m3/s, whereas the average ADC and Flowmate is 0.709 m3/s. Meanwhile, stream discharge has been calculated 0.709 m3/s through the broad-crested weir equation. The discharge has calculated with the weir equation greatly changed according to even a small change in the water level. However, it showed a similar trend to one of the observed discharge. Although, in past there were generating errors caused by observers’ strides, vertical and horizontal flow velocity distribution when the average flow velocity had been measured, non-prismatic flow, turbulent flow and others in ADC. This study comes up with the weir equation is more suitable for the characteristics of Jeju-do could be presented through an observations of baseflow discharge.

This study is carried out to propose an empirical equation which can promptly predict the aircraft noise level at a specific point (a receptor) near Jeju international airport by using the information of the flight path data. For this purpose, Analyses of multiple linear regression with the slant distances (SD) calculated from the gate analyses of the flight path data, aircraft noise certification levels with unit of EPNL(effective perceived noise level) and noise levels measured at receptors are performed by SPSS package. From these regression analyses for approach and departure of aircraft, we can propose empirical equations which is statistically significant. The noise levels predicted by these empirical equations are highly correlated the measured data.

본 연구에서는 2013년 영산강과 섬진강 유역에 발생한 강우 및 홍수사상을 평년 및 예년과 비교하여 분석하였다. 분석결과, 6월, 8월∼9월은 평년대비 50% 수준에 그쳤으나, 7월은 장마전선의 영향으로 4일부터 7일까지 유역평균 250mm 강우를 기록하였다. 8월은 작년과 달리 태풍의 직접적인 영향이 없었으나, 23일과 24일에는 유역평균 140mm의 호우가 집중되었다. 강우에 따른 수위 변화를 알아보면 연중 최고수위가 7월 5일에 발생하였고, 이 때에 선암(황룡강), 나주(영산강), 구례2와 송정지점(섬진강)에 홍수주의보가 발령되기도 하였다. 농업용 저수지(광주, 담양, 장성과 나주) 및 다목적 댐(섬진강, 주암, 탐진)의 11월말 수위를 보면 전반적으로 전년에 비하여 낮은 편이었고, 그 중 광주댐은 전년대비 4.60m, 섬진강댐은 9.15m으로 낮은 편이었다.

대추 분말의 첨가량을 0~20%로 달리하여 쿠키를 제조한 후 물리·화학적 품질, 항산화특성 및 소비자 기호도를 비교하였다. pH는 6.69~6.16 범위에서 유의적으로 감소하였고 (p<0.05), 수분함량은 점차적으로 증가하였다. 대추 분말을 첨가할수록 퍼짐성과 손실률은 유의적으로 감소하였고 (p<0.05), 손실률의 경우 5~15% 시료 간에서는 유의적인 차이는 없었다(p>0.05). 한편 명도(L*)는 대추 분말의 첨가량이 증가할수록 유의적으로 감소하였고, 적색도(a*)는 유의적으로 증가하였다(p<0.05). 황색도(b*)는 다소 증가하는 경향을 보였으나, 10~20% 첨가군 사이에 유의적인 차이는 발견되지 않았다(p>0.05). 경도와 DPPH radical 소거능은 유의적으로 증가하였으나(p<0.05), 일부 첨가군 사이에 유의적 차이는 발견되지 않았다(p>0.05). 소비자 선호도 검사 결과, 5% 첨가군이 대부분 높은 평점을 받았지만 대조군과 비교하여 유의적으로 높은 항산화활성이 측정되지 않아, 생리적 활성과 관능적 품질을 고려하면 첨가농도로 5~10% 사이가 적절한 것으로 판단된다.

본 연구는 관행포장과 유기포장에서 절지동물의 군집 구조와 생물다양성을 비교하기 위해 실시되었다. 조사기간 중 채집된 절지동물은 관행포장에서 6,901개체였으며 유기포장에서는 21,871개체로 총 28,718개체였으며 10목 24과 36종으로 동정되었으며 농법별 절지동물 군집을 구성하는 종수는 관행농과 유기농 모두 32종으로 같았고 관행포장에서는 파리목, 유기농에서는 벌목과 톡토기목의 종지수가 높았다. 대만총채벌레(F. intonsa)는 농법에 관계없이 발생밀도가 현저히 높았고 관행포장에서 우점종은 담배나방(H. assulta)이었고 유기포장에서는 줄무늬빗톡토기(H. mediaseta), 파리류 4(Diptera sp. 4) 및 별늑대거미(P. astrigera)였다. 절지동물 군집의 생물다양성은 지표면에서 종다양성이 관행포장에서 유기포장보다 높았으며 통계학적으로 차이가 있었다. 농법간 절지동물의 군집의 유사성은 지표면 및 지상부 식물체에서 활동하는 절지동물 군집은 대체로 농법에 의해 구분되었으며 그 유사도는 각각 34.07%와 26.95%로 비교적 낮아 농법간 이질성이 있었다. 생태학적 기능군의 종지수는 지상부 식물체에서 일반군, 해충군 및 천적군 중 기생포식자군에서 통계학적인 차이가 있었으며, 해충군과 기생포식자군 모두 유기포장에서 높았다. 발생밀도는 지표면에서 천적군 중 포식자군이 유기포장에서 관행포장에 비해 약 2배 정도 높았고 통계학적으로 차이가 있었다. 종다양성은 지상부 식물체에서 일반군과 천적군 중 기생포식자군에서 통계학적인 차이가 있었다. 개별 생태학적 기능군의 농법별 상대적 발생밀도 변동에서 관행포장에서는 해충군의 점유도가 높았고 유기농에서는 분해자군의 점유도가 현저히 높았다. 본 연구결과는 유기농업에서 효율적인 해충관리방안을 구축하는데 있어 유용한 절지동물 군집 정보를 제공할 것으로 사료된다.

Roughness coefficient was computed for review of applicability based on measurement of the representative grain diameter reflecting channel characteristics of Han Stream. After field survey, collection of bed material, and grain analysis on the collected bed material, roughness coefficient was computed using representative grain and existing empirical equation for roughness coefficient. Value of roughness coefficient calculated using equation by Meyer-Peter and Muller (1948) was 0.0417 for upstream, 0.0432 for midstream, and 0.0493 for downstream. As a result of comparing the computed roughness coefficient to other empirical equations for review of applicability, the coefficient was larger in Strickler (1923) equation by 0.006. Smaller coefficient was shown by Planning Report for River Improvement Works. Equation by Garde and Raju (1978) was larger by 0.004, and equations by Lane and Carlson (1953) and by Meyer-Peter and Muller (1948) were larger by 0.001. Such precise roughness coefficient is extremely important when computing the amount of flood in rivers to prevent destruction of downstream embankments and property damages from flooding. Since roughness coefficient is a factor determined by complicated elements and differs according to time and space, continued management of roughness coefficient in rivers and streams is deemed necessary.

Jeju Island, the heaviest raining area in Korea, is a volcanic Island located at the southernmost of Korea, but most streams are of the dry due to its hydrological/geological characteristics different from those of inland areas. Therefore, there are limitations in applying the results from the mainland to the studies on stream run-off characteristics analysis and water resource analysis of Jeju Island. In this study, the SWAT(soil & water assessment tool) model is used for the Hwabuk stream watershed located east of the downtown to calculate the long-term stream run-off rate, and WMS(watershed modeling system) and HEC-HMS(hydrologic modeling system) models are used to figure out the stream run-off characteristics due to short-term heavy rainfall. As the result of SWAT modelling for the long-term rainfall-runoff model for Hwabuk stream watershed in 2008, 5.66% of the average precipitation of the entire basin was run off, with 3.47% in 2009, 8.12% in 2010, and root mean square error(RMSE) and determination coefficient(R2) was 496.9 and 0.87, respectively, with model efficient(ME) of 0.72. From the results of WMS and HEC-HMS models which are short-term rainfall-runoff models, unless there was a preceding rainfall, the runoff occurred only for rainfall of 40mm or greater, and the run-off duration averaged 10～14 hours.

This study was conducted to determine physico-chemical properties and degree of heavy metal contamination of sediments collected at Tongyong channel. From XRF and XRD analyses, all samples consisted of similar oxides and minerals. TOC ranged between 1.73 and 2.79%. Ignition loss ranged between 9.31 and 12.28%. Degree of heavy metal contamination of sediments was performed based on standards proposed by USEPA, Ontario sediment quality guidelines, index of geoaccumulation and total enrichment factor. In summary, sediment T9 was classified as moderately contaminated region based on standards of USEPA, index of geoaccumulation and total enrichment factor. In addition, T7 and T8 were classified as moderately contaminated region based on only USEPA standard. However, concentrations of Cu and Zn of T7 and T8 gradually increased to the level of T9 where it was close to Tongyong harbor. Therefore, the regions of T7, T8 and T9 need to be monitored and if possible required to remediate contaminated sediments.