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Flood Runoff Analysis using Radar Rainfall and Vflo Model for Namgang Dam Watershed (레이더강우와 Vflo모형을 이용한 남강댐유역 홍수유출해석)

  • Park, Jin-Hyeog;Kang, Boo-Sik;Lee, Geun-Sang;Lee, Eul-Rae
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.3
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    • pp.13-21
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    • 2007
  • Recently, very short-term rainfall forecast using radar is required for regional flash flood according to climate change. This research is to evaluate the feasibility of GIS based distributed model using radar rainfall which can express temporal and spatial distribution in actual dam watershed during flood runoff period. Vflo model which was developed Oklahoma university was used as physical based distributed model, and Namgang dam watershed ($2,293km^2$) was applied as study site. Distributed rainfall according to grid resolution was generated by using K-RainVieux, preprocess program of radar rainfall, from JIN radar. Also, GIS hydrological parameters were extracted from basic GIS data such as DEM, land cover and soil map, and used as input data of distributed model(Vflo). Results of this research can provide a base for building of real-time short-term rainfall runoff forecast system according to flash flood in near future.

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Flood Runoff Simulation using Radar Rainfall and Distributed Hydrologic Model in Un-Gauged Basin : Imjin River Basin (레이더 강우와 분포형 수문모형을 이용한 미계측 유역의 홍수 유출모의: 임진강 유역)

  • Kim, Byung-Sik;Bae, Young-Hye;Park, Jung-Sool;Kim, Kyung-Tak
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.3
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    • pp.52-67
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    • 2008
  • Recently, frequent occurrence of flash floods caused by climactic change has necessitated prompt and quantitative prediction of precipitation. In particular, the usability of rainfall radar that can carry out real-time observation and prediction of precipitation behavior has increased. Moreover, the use of distributed hydrological model that enables grid level analysis has increased for an efficient use of rainfall radar that provides grid data at 1km resolution. The use of distributed hydrologic model necessitates grid-type spatial data about target basins; to enhance reliability of flood runoff simulation, the use of visible and precise data is necessary. In this paper, physically based $Vflo^{TM}$ model and ModClark, a quasi-distributed hydrological model, were used to carry out flood runoff simulation and comparison of simulation results with data from Imjin River Basin, two-third of which is ungauged. The spatial scope of this study was divided into the whole Imjin River basin area, which includes ungauged area, and Imjin River basin area in South Korea for which relatively accurate and visible data are available. Peak flow and lag time outputs from the two simulations of each region were compared to analyze the impact of uncertainty in topographical parameters and soil parameters on flood runoff simulation and to propose effective methods for flood runoff simulation in ungauged regions.

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Bibliographical studies on the shashen(Adenophora triphylla var. Japonica Hara.) (사삼(沙蔘)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Shin, Dong Hun;Seo, Young Bae
    • Journal of Haehwa Medicine
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    • v.8 no.2
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    • pp.107-122
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    • 2000
  • As a result of studing on the "shashen(沙蔘)", we could reach conclusions as follows. 1. Shashen is the root of "lunyeshashen(潤葉沙蔘)", "kuoyeshashen(闊葉沙蔘)", and its same generic plants that belong to Companulaceae. In china people has used twenty-four species as a shashen together with other generic plants, in korea sixteen species as a shashen. 2. At first, in the "Shen Nong's Herbal(神農本草經)" it was recorded and then in the "Benchingfengyuan(本經逢原)" divided into "nanshashen(南沙蔘)" and "beishashen(北沙蔘)". Recently, nanshashen called shashen belongs to Companulaceae and have strong efficacies of clearing away heat from lung, resolving phlegm, beishashen belongs to Umbelliferae and have strong efficacies of nourishing stomach, nourishing yin. 3. Shashen is the root of Adenophora stricta Miq., and yangru(羊乳) is that of Codonopsis lauceolata Bentham et Hooker, jini is that of Adenophora remotiflora (SIEBOLD et ZUCCARINI.) MIQUEL. From a efficacious point of view, it is the characteristics that shashen have efficacies of nourishing yin and clearing away heat from lung, supplementing stomach and promoting production of body fluid, resolving phlegm and relieving cough, eliminating pus and abscess, expelling wind and pruritus, jini have those of clearing away heat and toxic material, resolving phlegm and yanru have those of nourishing yin and moistening lung, resolving phlegm and eliminating pus, clearing away heat and toxic material, stimulating milk secretion. 4. After being recorded as "zhimu(知母)" in Shen Nong's Herbal, the alias of shashen was recorded as kuxin(苦心), shimei(識美), huxu(虎須), baishen(白參), zhiqu(志取), wenhu(文虎), baolishen(保利參), paoshen(泡參), jibantui(鷄半腿), yangponai(羊婆妨) and so on. Moreover shashen was named after its characteristics of that it grows well in the sandy soil and as a wushen(五參) with a renshen(人蔘) its form is different from that of wushen but their chief virtues are alike. 5. In the numerous medical books, xinyeshashen(杏葉沙蔘) regarded as nanshashen. It was called as the alias of jini, so I thouhgt that it was wrong xinyeshashen to be regarded as nanshashen. 6. It was used shashen for renshen, renshen was used to treat lung-cold syndrome by its efficacy of tonifying yang and shashen lung-heat syndrome by its efficacy of nourishing yin, the reasons of that because shashen had amount of sap, its properies and flavours of herbs are light and clean. 7. The constituents of shashen were essential oil, starch, shashen-saponin, furocoumarin, xanthotoxin(ammoidin), inulin, sugar, mucus and have efficacies of resolving phlegm, promoting production of body fluid, immunomodulational and antibiotic efficacies. above results indicated that the origin of shashen and substitutional plants was various. Their efficacies are somewhat alike, but there were characteristic efficacies each other. Nowadays they are used together with, so we should know the characteristic efficacies of them and then we using them clinically, more deep discrimination and experimental support shoud be accomplished.

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Studies on the Relation between Tree Injury and Acid Precipitation (수목피해와 산성강하물의 관련성에 관한 연구)

  • 이총규;김종갑;조현서
    • Korean Journal of Environment and Ecology
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    • v.12 no.2
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    • pp.131-137
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    • 1998
  • This study was performed to investigate tree injury with air pollution and acid precipitation in industrial area and rural area. This study analyzed the ion properties of pollutant precipitated in the forest of Ulsan & Onsan area and correlation between S $O_2$concentration in air and the degree of forest decline. pH of industrial area was lower than that of rural area and electrical conductivity and pH had a negative correlation(r=-.7861$^{**}$). Correlation of cation and anion(especially S $O_{4}$$^{2-}$, N $O_{3}$$^{[-10]}$ ) in precipitation and S $O_2$in air was higher in industrial area. In seasonal change, winter and spring were higher. In the analysis of correlation between forest decline and variables of precipitation properties, correlation coefficient was higher by following order: S $O_{4}$$^{2-}$>pH>EC>N $O_{3}$$^{[-10]}$ >S $O_{2}$$^{2-}$>C $l^{[-10]}$ . Regression formula by computation was Y = 5.1007-0.7811 $X_2$(pH) +0.0253 $X_{5}$ (S $O_{4}$$^{2-}$) +0.0275 $X_{6}$ (N $O_{3}$$^{[-10]}$ ). In considering the result of this study, it was predicted that air pollution and acid rain would affect soil acidification and forest decline continuously.y.

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Vegetation Characteristics of Geumnamhonam·Honam Ridge Areas Understood through Quantitative Vegetation Analysis (정량적 식생분석을 통한 금남호남·호남정맥 마루금 일대의 식생 특성)

  • Park, Seok-Gon;Kang, Hyun-Mi
    • Korean Journal of Environment and Ecology
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    • v.34 no.4
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    • pp.304-317
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    • 2020
  • This study conducted selected two sites in Geumnamhonam and four sites in Honam-Jeongmaek for vegetation survey with consideration to the location environment and anthropogenic impacts to investigate the vegetation structures of the Geumnamhonam-Jeongmaek·Honam-Jeongmaek ridge areas. Using TWINSPAN (two-way indicator species analysis), each of the two ridge areas were categorized into seven plant communities. The differential species in the TWINSPAN technique indirectly represent the environmental factors of plant communities, and the community types of the two ridge areas were divided based on environmental factors such as altitudes above sea level, soil moisture, and disturbance. These results were in harmony with the environmental factors of the DCA (detrended correspondence analysis) axis 1. In the low-lying areas of both ridge areas, afforestation tree species such as Pinus rigida and P. thunbergii were in competition with native tree species. As such, in the low-lying areas, artificial vegetation disturbance was severe due to afforestation and development projects. In relatively highland areas, such as upper slopes, and top areas, in the ridge, the vegetation type with the dominance of Quercus mongolica, Q. variabilis, and P. densiflora was preserved well. As for differences between the two ridge areas, communities dominated by Q. mongolica were distributed widely in Geumnamhonam-Jeongmaek because of the altitudes above sea level, and the latitude of this ridge area are higher than those of Honam-Jeongmaek. On the other hand, communities dominated by P. densiflora were distributed along with communities dominated by Q. mongolica, and communities dominated by Q. variabilis appeared in Honam-Jeongmaek because it is adjacent to the south coast. In quantitative vegetation analysis such as TWINSPAN and DCA, changes in species composition and the extracting environmental factors that cause the changes are important. To that end, the removal of accidental emergent species, the establishment of an investigation plan that assumes environmental factors, and the selection of the optimal analytical method suitable for the characteristics of the survey data are necessary.

Development of Site Classification System and Modification of Design Response Spectra considering Geotechnical Site Characteristics in Korea (II) - Development of Site Classification System (국내 지반특성에 적합한 지반분류 방법 및 설계응답스펙트럼 개선에 대한 연구 (II) - 지반분류 개선방법)

  • Yoon, Jong-Ku;Kim, Dong-Soo;Bang, Eun-Seok
    • Journal of the Earthquake Engineering Society of Korea
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    • v.10 no.2 s.48
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    • pp.51-62
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    • 2006
  • In the companion paper (I-Problem Statements of the Current Seismic Design Code), the current Korean seismic design code is required to be modified considering site characteristics in Korea for the reliable estimation of site amplification. In this paper, three site classification methods based on the mean shear wave velocity of the top 30m $V_{S30}$, fundamental site periods $(T_G)$ and bedrock depth were investigated and compared with each other to determine the best classification system. Not enough of a difference in the standard deviation of site coefficients $(F_a\;and\;F_v)$ to determine the best system, and neither is the difference between the average spectral accelerations and the design response spectrum of each system. However, the amplification range of RRS values based on $T_G$ were definitely concentrated on a narrow band than other classification system. It means that sites which have a similar behavior during earthquake will be classified as the same site category at the site classification system based on $T_G$. The regression curves between site coefficients and $T_G$ described the effect of soil non linearity well as the rock shaking intensity increases than the current method based on $V_{S30}$. Furthermore, it is unambiguous to determine sue category based on $T_G$ when the site investigation is performed to shallower depth less than 30m, whereas the current $V_{S30}$ is usually calculated fallaciously by extrapolating the $V_s$ of bedrock to 30m. From the results of this study, new site classification system based on $T_G$ was recommended for legions of shallow bedrock depth in Korea.

Evaluation of Site-Specific Seismic Amplification Characteristics in Plains of Seoul Metropolitan Area (서울 평야 지역에 대한 부지 고유의 지진 증폭 특성 평가)

  • Sun, Chang-Guk;Yang, Dae-Sung;Chung, Choong-Ki
    • Journal of the Earthquake Engineering Society of Korea
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    • v.9 no.4 s.44
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    • pp.29-42
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    • 2005
  • Total 350 borehole profiles were selected from the database of borehole logs in Seoul, for the site-specific seismic evaluation at two 4km${\times}$4km plain areas. Equivalent-linear site response analyses for the selected 350 sites were conducted based on shear wave velocity (Vs) Profiles, which were determined from the N-Vs correlation established using borehole seismic testing results in the inland areas of Korea. Most sites were categorized as site classes C and D based on the mean Vs to 30 m in depth (Vs30) ranging from 250 to 550 m/s. The she periods of the plains in Seoul ranging between 0.1 and 0.4 sec were significantly lower than those of the western US, from which the site coefficients in Korea were derived. For plains in Seoul, the site coefficients, Fa's and Fv's specified in the Korean seismic design guide, underestimate the ground motion in short-period (0.1-0.5 sec) band and overestimate the ground motion in mid-period (0.4-2.0 sec) band, respectively, because ol the differences in the geotechnical conditions between Seoul and the western US, although the Fa's in several sites overestimate the motion due to the base Isolation effect resulted from the soft layer in soil deposit.

Damaged Aspects, Seasonal Fluctuations, and Attractivity of Various Colors on Liriomyza trifolii Burgess (Diptera: Agromyzidae) in Gerbera (거베라에서 아메리카잎굴파리의 가해양상, 발생소장 및 색상별 유인량)

  • 박종대;구용수;최덕수;김상수
    • Korean journal of applied entomology
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    • v.40 no.2
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    • pp.97-103
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    • 2001
  • The rate of gerbera (Gerbera jamesonii Bolus.) leaf damaged by Liriomyza trifolii larvae was lower than that by adults. The adults began to be attracted to yellow sticky trap immediately after transplanting and increased gradually up to early August followed by low population density from middle to late August. In the second year, adults began to be attracted from late April after transplanting and increased abrubtly from middle May and the high density was maintained till early truly. The density decreased, however, from middle July, and then followed by the high density again early September and late October The seasonal fluctuations of larva and pupa were similar to that of adults and the peaks of pupa occurred one week later than that of larvae. Larva infected by parasitoid were observed 4 weeks after transplanting. Parasitism was 65% in average from early July to late August but decreased to 50% from early September. Number of trapped adults was the highest in the yellow sticky trap among the five different colour raps. Catches at 30~60 cm above soil surface were significantly greater than that at 90 cm.

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Soil Micro-arthropods Fauna in Plantations of the Korean White pine (Pinus koraiensis) -1. Composition of Oribatid Mites(Acari: Cryptostigmata)- (잣나무 조림지내 토양미소 절지동물상에 관한 연구 1. 날개응애종의 구성)

  • 권영립;최성식
    • Korean journal of applied entomology
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    • v.31 no.1
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    • pp.10-22
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    • 1992
  • Oribatid mites communities at plantations of the Korean white pine (Pinus koraiensis) were investigated for the composition and distribution at the Sudong area, Namyangju-gun, Kyung-gido, Korea. Oribatid mites collected were classified into 38 families, 64 genera, and 109 species. Among them the eurysphere, stenosphere, and sporosphere species were 35, 49, and 25 species, respectively. The species diversity of oribatid mites increased at sites from 3 years after to 5 years after transplanting and then decreased by afforested years. The dominant species of oribated mites at the surveyed areas were 6 species including Ceratozetes japonicus. Number of dominent species and recessive species decreased by afforested years. However, influential species increased. According to the MGP analysis I, type G was found in all sites. The eurysphere and the sporosphere species were type G. The stenosphere species were type P at an earlier planting stage, type G at a middle planting stage, type M at a latter planting stage. The semieurysphere species were type M. According to the MGP analysis II, site 1, 2, and 4 were type G, but site 3, 5, and 6 were type P.

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Evaluation of Bio-Control Efficacy of Trichoderma Strains against Alternaria alternata Causing Leaf Blight of Ashwagandha [Withania somnifera (L.) Dunal]

  • Rahman, Md. Ahsanur;Rahman, Md. Arifur;Moni, Zakiah Rahman;Rahman, Mohammad Anisur
    • Journal of Forest and Environmental Science
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    • v.36 no.3
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    • pp.207-218
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    • 2020
  • Ashwagandha is an important ancient medicinal crops, being affected with many diseases, among which leaf blight caused by Alternaria alternata has become the constraint resulting in huge yield losses. Continuous usage of chemical methods leads to environment, soil and water pollution. Whereas biological control of diseases is long lasting, inexpensive, eco-friendly and harmless to target organisms. In this context, it is aimed to evaluate five Trichoderma strains viz. Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433 and T. harzianum IMI-392434 as bio-control efficacy against A. alternata and growth promoting effect in Ashwagandha. All the Trichoderma strains had varied antagonistic effects against the pathogen. In dual culture technique, the strain T. harzianum IMI-392433 showed maximum percentage inhibition of mycelial growth (54.89%) followed by T. harzianum IMI-392432 (53.83%), T. harzianum IMI-392434 (48.94%) and T. virens IMI-392430, (43.62%) against the pathogen, while the least inhibition percentage was observed with the T. pseudokoningii IMI-392431 (36.60%). The culture filtrate of the Trichoderma strain, T. harzianum IMI-392433 recorded highest inhibition on the mycelial growth (39.05%) and spore germination (80.77%) of pathogen and the lowest was recorded in T. pseudokoningii IMI-392431 (20.45 and 50%). Moreover, seeds treated with spore suspension of the strain T. harzianum IMI-392433 reduced the percentages of disease severity index significantly. The strain T. harzianum IMI-392433 also significantly increased seed germination %, seedling vigor and growth of Ashwagandha. The correlation matrix showed that root yield per plant of Ashwagandha had significant and positive correlation with plant height (r=0.726⁎⁎), number of leaf (r=0.514⁎⁎), number of primary branch (r=0.820⁎⁎), number of secondary branch (r=0.829⁎⁎), fresh plant weight (r=0.887⁎⁎), plant dry weight (r=0.613⁎⁎), root length (r=0.824⁎⁎), root diameter (r=0.786⁎⁎), root dry weight (r=0.739⁎⁎) and fresh root weight (r=0.731⁎⁎). The significant and negative correlation (r=-0.336⁎⁎) was observed with the root yield and percentages of disease severity index. The study recognized that the T. harzianum IMI-392433 strain performed well in inhibiting the mycelial growth and reduced the percentages of disease severity index of pathogen as well as increased the plant growth in Ashwagandha.