• Journal of Environmental Science International
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• v.17 no.6
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• pp.679-687
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• 2008

In this study, we implemented landslide distribution of Jeju Island using ANN and GIS, respectively. To do this, we first get the counter line from 1:2,5000 digital map and use this counter line to make the DEM. for the evaluate the land slide susceptibility. Next, we abstracted slop map and aspect map from the DEM and get the land use map using ISODATA classification method from Landsat 7 images. In the computation processes of landslide analysis, we make the class to the soil map, tree diameter map, Isohyet map, geological map and so on. Finally, we applied the ANN method to the landslide one and calculated its weighted values. GIS results can be calculated by using Acrview program and produced Jeju landslide susceptibility map by usign Weighted Overlay method. Based on our results, we found the relatively weak points of landslide ware concentrated to the top of Halla mountains.

• Journal of Environmental Science International
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• v.17 no.1
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• pp.19-27
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• 2008

Artichoke extracts are widely used alone or in association with other herbs for embittering alcoholic and soft drinks and to prepare herbal teas or herbal medicinal products in Viet Nam. The objective of this paper was a screening of flavonoids and total phenolic compounds content in the parts of artichoke (Cynara scolymus L.) as flowers, leaves, roots, trunks, stumps, The total phenolic compounds and flavonoids in the parts of artichoke were extracted among 3 extraction methods as methanol extraction (EM1), mixing methanol and water method (EM2) and water extraction method (EM3). Total phenolic compounds and flavonoids were determined by UV/VIS, HPLC techniques. The apigenin 7-O-glucosides, cynarin, narirutin, gallic acid, caffeic acid were found as the main flavonoids constituents in all parts of artichoke. It showed that value of total phenolic compounds and flavonoids by EM3 were higher than that of total phenolic compounds and flavonoids by EM1 and EM2. Furthermore, the results of this study revealed that total phenolic compounds and flavonoids, obtained by these convenient extraction methods, may show the quick efficacy of artichoke in all respects of their quality and quantity.

• Journal of Environmental Science International
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• v.20 no.5
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• pp.581-587
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• 2011

Industrial natural ventilation systems consist of gravity ventilator, the high/low windows and doors. Especially, the high windows play an important role in the industrial natural ventilation systems. Generally speaking, industrial high windows are divided into 3 types; louver type, $45^{\circ}$ open type and $90^{\circ}$ open type. This study was numerically and experimentally conducted. Three types of windows were tested to know the ventilation characteristics and estimate the ventilation efficiencies. Numerically, computational fluid dynamics software (AIR PAK Ver. 2.0) was used to observe the flow characteristics inside the industrial building and the concentration contours generated by the tracer gas method. Experimentally, the flow visualization technique and the tracer gas method were applied with the model building to characterize the flow pattern inside the model building and to estimate the ventilation efficiencies with the different windows. It was found that $90^{\circ}$ open type window was most effective for the discharge of pollutants from the industrial building. On the other hand, the louver type window was found to be less effective than any other windows.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1447-1454
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• 2010

In this study, the detection limits of lower fatty acids in air were investigated by using Dynamic SPME(Solid Phase Micro-Extraction), i.e. improved Head Space - SPME method(HS-SPME). This Dynamic SPME, called SPDE(Solid Phase Dynamic Extraction), is the analytical method for volatile compounds in air with the extraction by using a stainless steel needle of which inner surface is coated with adsorption material and following the gas chromatographic analysis by inserting the needle into a injection port of GC and subsequently, desorption of the volatile compounds into a gas-chromatographic column. Extraction was carried out by passing the sample air through the needle with a suction pump which has been used for a detection tube. The result of measurement for the 6 lower fatty acids showed that the detection limits ranged from 0.10 ppm to 0.44 ppm and the linear correlation coefficients were over 0.99. Relative standard deviations obtained from 5 analytical repetition of a ca. 1.6 ppm standard mixture were in the range of 1.87%~2.47%. This method has been shown to be a adequate for the measuring C2~C5 fatty acids in air in the concentrations of over several hundreds ppb.

• Journal of Environmental Science International
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• v.20 no.10
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• pp.1347-1355
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• 2011

In Jeju island, runoff has frequently happened when the rainfall depth is over a threshold value. To simulated this characteristic rainfall-runoff model structure has to be modified. In this study, the TRSM (Threshold Runoff Simulation Method) was developed to overcome the limitations of SWAT in applying to the hydrologic characteristics of Jeju island. When the precipitation and soil water are less than threshold value, we revised the SWAT routine not to make surface/lateral or groundwater discharge. For Hancheon watershed, the threshold value was set as 80% of soil water through the analysis of rainfall-runoff relationship. Through the simulation of test watershed, it was proven that TRSM performed much better in simulating pulse type stream flow for the Hancheon watershed.

• Journal of Environmental Science International
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• v.18 no.12
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• pp.1427-1436
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• 2009

The purpose of this study was to explain community structure for actual vegetation and their environment variables in Anmyeon Island. Samples were collected for 106 plots using ZM phytosociology method and coincidence method. Actual vegetation were classified into three vegetations types(forest vegetation type, maritime vegetation type, lake vegetation type) and eleven community units. Pourthiaea villosa community in forest vegetation type was divided into 5 groups such as Carpinus coreana group, Pinus rigida group, Chamaecyparis obtusa group, Castanea crenata group and Typical group. Maritime vegetation type was divided into 3 communities, such as Vitex rotundifolia community, Koelreuteria paniculata community and Suaeda japonica community. V. rotundifolia community was subdivided into 2 groups, Rosa rugosa group and Diodia teres group. K. paniculata community was subdivided into 2 groups, Grewia biloba var. parviflora group and Typical group. Lake vegetation type was divided into 1 community, Nelumbo nucifera community. And it was entirely classified into 11 community units.

• Journal of Environmental Science International
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• v.15 no.9
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• pp.855-864
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• 2006

This study introduces a method to eliminate formaldehyde and benzene, toluene from indoor air by means of a photocatalytic oxidation reaction. In the method introduced, for the good performance of the reaction, the effect and interactions of the $TiO_2$ catalyst and ultraviolet in photocatalytic degradation on the reaction area, dosages of catalysts, humidity and light should be precisely examined and controled. Experiments has been carried out under various intensities of UV light and initial concentrations of formaldehyde, benzene and toluene to investigate the removal efficiency of the pollutants. Reactors in the experiments consist of an annular type Pyrex glass flow reactor and an 11W germicidal lamp. Results of the experiments showed reduction of formaldehyde, benzene and toluene in ultraviolet $/TiO_2/$ activated carbon processes (photooxidation-photocatalytic oxidation-adsorption processes), from 98% to 90%, from 98% to 93% and from 99% to 97% respectively. Form the results we can get a conclusion that a ultraviolet/Tio2/activated carbon system used in the method introduced is a powerful one for th treatment of formaldehyde, benzene and toluene of indoor spaces.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.335-342
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• 2008

This study based on electro-coagulation & oxidation reaction is applied to wastewater treatment. Electro-oxidation reaction is used to remove cyanide(CN) which is contained in plating wastewater. Cyanide is transferred by gases such as $NH_3,\;NO_x,\;CO_2$. Analysis result and removal efficiency of Cyanide which is contained in heavy metal wastewater of plating plant, are shown as following paragraph. In electrode arrangement experiment, removal efficiency of carbon electrode(-)/STS316L electrode(+) arrangement method is superior to carbon electrode(-)/carbon electrode(+) arrangement method. Removal efficiencies of cyanide in different HRT such as 30 min, 45 min, 60 min, 75 min and 90 min are 85.5%, 93.1%, 98.0%, 98.7% and 99.4% respectively in carbon electrode(-)/STS316L electrode(+) arrangement method. Finally we can estimate the critical point at HRT of 60 min which the variation of removal efficiency is decreased and HRT to obtain removal efficiency of less than 1 mg/LCN is minimum 90 min.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.1061-1068
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• 2011

Evapotranspiration is one of the important elements related water cycle and there is many kind of measurement method of evapotranspiration today. This study developed mini lysimeter for the purpose of direct measurement of evapotranspiration and installed on 5th, July, 2010 at the field of MRI which located at Tsukuba, Ibaraki, Japan for continuous measurement and understand relation between evapotranspiration and meteorological elements expecially radiation elements. And compared the evapotranspiration data of lysimeter with Bowen Ratio Method. The result of this study is as follows; There is high related with solar radiation and evapotranspiration with $R^2$=0.947. and 46 % of solar radiation converted into evapotranspiration during clear 5 days. In net radiation also highly related with evapotranspiration, we can derive evapotranspiration is mainly controlled by radiation energy in clear days. From the 104 days data, there is only 9 % difference between Bowen Ratio Method and evapotranspiration of lysimeter which was developed from this study is very useful to estimate evapotranspiration at field site with simple and high accuracy. High accuracy and resolution measurement of evapotranspiration by lysimeter can give a chance further study of meteorological phenomena of on ground expecially in night time condensation which means abnormal energy flow.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.119-124
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• 2003

An effective grafting method for jujube nursery trees was developed to shorten the operation time, improve the percentage of "takes" and shoot emergence, and form the better graft union. Out of 7 grafting methods the splice, modified scion Ono graft and the bark graft showed relatively short operation time during the grafting operation comparing to the modified rootstock Ono graft or the chip budding. Among these methods, the bark graft demonstrated 100% "takes", but the modified scion Ono graft or the standard Ono graft showed 58.3% of "takes". The percentages of the vegetative shoot emergence were 100% fir the bark graft, 70% f3r the modified scion Ono graft and lower emergence percent for the rest grafting methods. The union tissue formation for the modified scion Ono graft, the bark graft, or the whip-and-tongue graft was significantly larger than the standard Ono graft or the splice graft. In a close examination of the cross sectional areas of the graft union formation through the microscope, the bark graft was superior, the standard Ono graft was inferior and rest of the grafting methods were intermediate.ing methods were intermediate.