• 제목/요약/키워드: 3D-Var

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Variational Data Assimilation for Optimal Initial Conditions in Air Quality Modeling

  • Park, Seon-Ki
    • Journal of Korean Society for Atmospheric Environment
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    • 제19권E2호
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    • pp.75-81
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    • 2003
  • Variational data assimilation, which is recently introduced to the air quality modeling, is a promising tool for obtaining optimal estimates of initial conditions and other important parameters such as emission and deposition rates. In this paper. two advanced techniques for variational data assimilation, based on the adjoint and quasi-inverse methods, are tested for a simple air quality problem. The four-dimensional variational assimilation (4D-Var) requires to run an adjoint model to provide the gradient information in an iterative minimization process, whereas the inverse 3D-Var (I3D-Var) seeks for optimal initial conditions directly by running a quasi -inverse model. For a process with small dissipation, I3D-Vu outperforms 4D-Var in both computing time and accuracy. Hybrid application which combines I3D-Var and standard 4D-Var is also suggested for efficient data assimilation in air quality problems.

제주도 비자림에서의 세포성 점균의 분포 및 비자열매 추출액의 성장 효과에 관한 연구 (A Study on the Distribution and the Effect of Torreya Fruit Extract on Cellular Slime Molds in Torreya Forest of Cheju Island)

  • 최선영;장남기
    • 아시안잔디학회지
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    • 제10권3호
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    • pp.187-194
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    • 1996
  • Dictyostelid cellular slime molds were isolated from soils and harks of the subtropical forest of Torreya nucifera in Cheju island. The results were as follows: Polysphondylium pallidum,Dictyostelium purpureum, D. mucoroides, D. aureo-stipes var. aureo-stipes, D. flavidum, D. miniutum, P.violaceu m, D. monocrhasioides. D. brefeldianum, D. polvcephalum. D. areum var. areum, P. tenuissimum, D. fasciculatum. In this forest, P. pallidum and D. purpureum were occurred dominantly, and D. mucoroides and D. aureo-stipes var, aureo-stipes were the second dominant. It was distinguished that D. purpureum was much more cornmonly found than the other forests. Cellular slime molds from the barks of the tree heights of 1,3 and 5m were occured 7, 3 and 2 species respectively. Torreya fruit extract affected on the growth of D. aureo-stipes var. aureo-stipes and D. flavidum but not on D. purpureum and D. mucoroides. Key words: Cellular slime mold, Torreya forest, Torreya fruit extract.

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Dubautia속(屬) 3종(種) 식물(植物)의 엽육조직(葉肉組織) 미세구조(微細構造) 비교연구(比較硏究) (Comparison of Foliar Ultrastructure of 3 Dubautia species)

  • 김인선
    • Applied Microscopy
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    • 제24권4호
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    • pp.13-31
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    • 1994
  • 피자식물내 엽육조직 미세구조연구의 일환으로 형태해부학적으로 매우 다른 특성을 지닌 국화과 Dubautia속 식물 3종(Dubautia scabra var. leiophylla, D. knudsenii, D. scabra var. leiophylla, D. knudsenii)의 엽육조직이 연구되었다. 부모종 엽육조직의 형태해부학적 특성과 그들의 잡종 엽육조직세포의 분화 정도를 추정하기 위하여 palisade mesophyll내의 chloroplasts, microbodies, mitochondria 및 grana내의 thylakoid membrane system, phytoferritin-like structures, plastoglobuli와 starch grain 등 엽록체 내부의 초미세구조 형질들을 중점적으로 비교 분석하였다. 잡종의 엽육조직세포들은 형태해부학적 엽육형질 및 thylakoidal membrane system 등의 형질에서 부모종 엽육조직의 중간적 특성 (intermediacy)을 나타내어 전형적인 bilateral inheritage를 보여주었으며, thylakoid membrane number/granum, phytoferritin-like structures, starch grain의 분포 등에서는 어느 한 부모종 형질과 더 유사하게 관찰되었다. 미소체 및 미토콘드리아는 대체로 비슷한 양상으로 관찰되었고 phytoferritin-like structures는 국화과 식물 엽록체내에서 처음 보고되는 미세구조이다.

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Flavonoids from the Leaves of Betula platyphylla var. latifolia

  • Lee, Min-Won
    • 생약학회지
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    • 제25권3호
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    • pp.199-203
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    • 1994
  • Chemical examination of the leaves of Betula platyphylla var. latifolia has led to the isolation and characterization of five flavonoid glycosides including two C-glucosyl flavonoids. The structures of these compounds were elucidated as myricetin $3-O-{\alpha}-_L-rhamnoside$ (myricitrin), $quercetin-3-O-{\beta}-_D-glucopyranoside$ (isoquercitrin), $quercetin-3-O-{\beta}-_D-glucopyranoside$ (hyperoside), $nalingenin-6-C-{\beta}-_D-glucopyranoside$ (hemiphloin) and $aromadendrin-6-C-{\beta}-_D-glucopyranosidre(6-C-glucosyldihydrokaempferol)$ on the basis of physico-chemical and spectroscopic evidences.

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하천(곡릉천,안양천)변 토양에서 세포성 점균의 분포 및 토양 환경요인의 영향 (The Distribution of Dictyostelids Cellular Slime Molds in Gokneung and Anyang Streamside and Effects of Environmental Factors on Its Distribution)

  • 권혜련;장남기
    • 아시안잔디학회지
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    • 제10권3호
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    • pp.195-211
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    • 1996
  • Dictyostelids cellular slime molds were isolated from the soils of Gokneung and Anyang streamside in Korea. The fifteen species including two undescrihed species were identified. These were as follows ; Dictyostelium macrocephalurn D. sphaerocephalum, D. aureum var. aureum, D.mucoroides, D. minutum, Polyspondyium pallidum. D. giganteum, P. violaceum. D. purpureum. D.brefeldianum, D. flavidum, D. mucoroides var. storoniferum, D. septentrionalis, D. aureum var. luteolum,D. aureo-stipes var. aureo-stipes. D. macrocephalum was the dominant species. and D. sphaerocephalum. D. aureum var. avreum were relatively common. D. mucoroides var. storoniferum, D. septentrionalis were the undescrihed species in Korea. In the soils of streamside, dominant species was shifted by D. macrosephalum, D. sphaerocephalum. which were rare in the forest soils. The total clones per gram of streamside soils were greater than that of forest soils, whereas the number of species in streamside was smaller than the in forest soils. As a result, the ratio of the number of clones to species was very high in the soils of streamside, Environmental factors of soil pH, water content, organic content, total nitrogen and total phosphorus made a effect differently on the cellular slime molds community. Key words: Cellular slime molds, D. macrocephalum, D. sphaerocephalum, Shift of dominant species, Environmental factors.

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자외선(UV)-B 조사에 의한 아위느타리버섯(Pleurotus eryngii var. ferulae) 자실체의 비타민 D2 함량 증가 (Ultraviolet (UV)-B Irradiation Increased Vitamin D2 Contents in the Fruit Bodies of Pleurotus eryngii var. ferulae)

  • 노재영;박상돈
    • 미생물학회지
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    • 제49권2호
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    • pp.191-194
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    • 2013
  • 아위느타리버섯(P. eryngii var. ferulae)의 비타민 $D_2$ (ergocalciferol) 함량 증강을 위하여 아위느타리버섯 자실체에 자외선(UV)-B파장(280-320 nm)을 조사하였다. 비타민 $D_2$ (ergocalciferol)의 증가된 함유량은 HPLC (Waters 1525, USA) 분석으로 확인하였다. 비타민 $D_2$ 함량은 3분($21.6KJ/m^2$) 처리시 $3.5{\mu}g/g$, 5분($36KJ/m^2$) 처리시 $6.02{\mu}g/g$으로 자외선을 조사하지 않은 대조군 $0.01{\mu}g/g$에 비교하여 높은 증가를 나타내었다. 이와 함께 큰느타리버섯(P. eryngii)은 대조군 $0.09{\mu}g/g$, 3분 처리시 $2.75{\mu}g/g$, 5분 처리시 $5.21{\mu}g/g$으로 나타났다. 표고버섯(L. edodes)은 대조군 $0.02{\mu}g/g$, 3분 처리시 $3.02{\mu}g/g$, 5분 처리시 $3.78{\mu}g/g$으로 나타났다. 느타리버섯(P. ostreatus)은 대조군 $0.19{\mu}g/g$, 3분 처리시 $9.63{\mu}g/g$, 5분 처리시 $11.60{\mu}g/g$으로 나타났다. 느타리버섯(P. ostreatus)의 비타민 $D_2$ 함량이 아위느타리버섯, 큰느타리버섯과 표고버섯 보다 높았으나 비타민 $D_2$ 함량 증가율은 아위느타리버섯이 월등히 높았다.

한약 "구맥(瞿麥)"의 생약학적 연구 (Pharmacognostical Studies on the Chinese Crude Drug 'Gu Maig')

  • 정지형;정애영;박종희
    • 생약학회지
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    • 제30권3호
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    • pp.320-327
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    • 1999
  • 'Gu Maig(瞿麥)' is one of the Chinese crude drugs used mainly to cure a diuretic, gonorhoea and menostasis, etc. With regard to the botanical origin of 'Gu Maig', it has been considered to be Dianthus spp. of Caryophyllaceae, but there has not been studied pharmacognostically. To clarify the botanical origin of the "Gu Maig", the morphological and anatomical characteristics of the leaves and stems of Dianthus species growing in Korea, i.e. D. sinensis, D. superbus var. longicalycinus, D. repens, D. morii, D. superbus var. speciosus were compared. As a result, it was determined that 'Gu Maig' was the whole plant body of Dianthus sinensis and D. superbus var. longicalycinus.

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꽃치자 지하부의 식물화학적 성분 (Phytochemical Compounds from the Underground Parts of Gardenia jasminoides var. radicans Makino)

  • 문형인;오좌섭;김종식;진배준;지옥표
    • 생약학회지
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    • 제33권1호통권128호
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    • pp.1-4
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    • 2002
  • The phytochemical study of the underground parts of Gardenia jasminoides var. radicans Makino (Rubiaceae) led to the isolation of five coumarins. On the basis of spectroscopic evidences, the structures of these compounds were charaterized as ferulic acid(l), 5,8-di-(3-methyl-2,3-dihydroxybutyloxylpsoralen)(2), skimmin(3), uracil(4), $3-0-{\alpha}-D-glucopyranosyl-(1{\rightarrow}4)-{\beta}-D-glucopyranosyloxypeucedanin$ hydrates(5), respectively.

Two Cyanidin compound from the Fruits of Acanthopanax divaricatus var. albeofructus

  • Hahn, Dug-Ryong;Park, Seon-Jin
    • Natural Product Sciences
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    • 제16권3호
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    • pp.198-201
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    • 2010
  • Acanthopanax divaricatus var. albeofructus is one of the indigenous medicinal plant and the fruits of Acanthopanax spp. used as a remedial for "wipe out evil wind". Two anthocyanin were isolated from the fruits of Acanthopanax divaricatus var. albeofructus. Their structures were elucidated as cyanidin 3-lathyroside (1) and cyanidin 3-galactoside (2) by chemicophysical and spectroscopic analysis. And also, four chemical, syringin, chlorogenic acid, caffeic acid and acanthoside D were identified. Both anthocyanide were isolated for the first time from Acanthopanax species. cyanidin 3-lathyroside is one of the rare anthocyanin in natural resources.

Constituents of the Herb of Isodon excisus var. coreanus

  • Kim, Ho-Kyoung;Whang, Wan-Kyunn;Kim, Il-Hyuk
    • Archives of Pharmacal Research
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    • 제20권3호
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    • pp.291-296
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    • 1997
  • The studies were carried out to evaluate the constituents in the aerial part of Isodon excisus var. coreanus (Labiatae). From the aqueous fraction of methanol extract, compound I (${\alpha}$-[[3-(3, 4-dihydroxyphenyl)-1-oxo-2-propenyl]oxy]-3,4-dihydroxy-benzenepropanoic acid), compound II (9-methyl-dihydroferulic acid-4-O-.betha.-D-glucopyranosyl $(1{\rightarrow}2)$-${\alpha}$-L- rhamnopyranosyl (1.rarw.4)-.betha.-D-glucopyranoside), compound III (ent-7.alpha., 11${\alpha}$,15.betha.-trihydroxy-kaur-16-en-1-O-.betha.-D-glucopyranoside) and compound IV ($2{\alpha}$,3${\beta}$,$7{\alpha}$,23-tetrahydroxy-olean-12 -en-28-oic acid 28-O-${\beta}$-D-glucopyranoside) were isolated and identified on the basis of their physicochemical and spectroscopic evidences[IR, FAB(-)MS,$^{1}H-NMR,$$^{13}C-NMR,$$ HMQC$$^{1}H-^{1}H $COSY and HMBC (Heteronuclear Multiple Bond Connectivity)]. Especially, New compounds II and III were named Isodonin A and Isodonin B respectively.

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