• Title/Summary/Keyword: non-polar

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Source Characterization of Suspended Particulate Matter in Taegu Area, Using Principal Component Analysis Coupled with Multiple Regression (주성분/중회귀분석을 이용한 대구지역 대기중 부유분진의 발생원별 특성평가)

  • 백성옥;황승만
    • Journal of Korean Society for Atmospheric Environment
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    • v.8 no.3
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    • pp.179-190
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    • 1992
  • This study was carried out to characterize sources of atmospheric total suspended particulates (TSP) in urban and sub--urban areas of metropolitan taegu. The sources were tentatively identified by a multivariate technique, i.e. principal component analysis (PCA), and the source contributions to the atmospheric concentrations of TSP were further estimated by stepwise multiple regression analysis. A total of 5 sources was identified in the urban area of Taegu (soil dust resuspension, fuel combustion, secondary aerosol, traffic related aerosol, and refuge burning), while 4 sources were found to be significant in the sub--urban area as following: fuel combustion/secondary aerosol, soil dust resuspension, traffic related aerosol, and wood/agricultural burning. The largest contributor to the atmospheric TSP appeared to be the soil dust resuspension in both areas. The source apportionment of the extractable organic matter (EOM) was also carried out for the Taegu data. The EOM was determined with respect to the solvent polarity, i.e. cyclohexane (non-polar), dichloromethane (semi--polar), and acetone (polar). In addition, the source profiles for the TSP in Taegu area were estimated using a PCA-based algorithm, and the validity was evaluated tentatively by comparing the data in the literature.

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All Sky Camera and Fabry-Perot Interferometer Observations in the Northern Polar Cap

  • Wu Qian;Killeen Timothy L.;Solomon Stanley C.;McEwen Donald J.;Guo, Weiji
    • Ocean and Polar Research
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    • v.24 no.3
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    • pp.237-247
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    • 2002
  • We report all sky camera and Fabry-Perot interferometer (FPI) observations of mesospheric gravity waves and a 12-hour wave at Resolute $(75^{\circ}N)$ and a joint observation of 10-hour wave with Eureka $(80^{\circ}N)$. All sky camera observations showed a low occurrence of mesosphere gravity waves during equinoxes, which is similar to the mid-latitude region. A slightly higher occurrence near solstice appears to indicate that gravity waves are not filtered out by the neutral wind in the winter. The FPI observation of a 12-hour wave showed amplitude variations from day to day. The phase of the wave is mostly stable and consistent with the GSWM prediction in the winter. The phase shifts with season as predicted by the GSWM. Four events of the 12-hour wave were found in spring with amplitudes larger than the GSW predictions. The FPls at Resolute and Eureka also observed a wave with period close to 10 hours. The 10-hour wave maybe the result of the non-linear interaction between the semi-diurnal tide and the quasi-two day wave. Further studies are under way. Overall, the combined Resolute and Eureka observation have revealed some new fractures about the mesospheric gravity wave, tidal wave, and other oscillations.

A Study on Automatic Target Recognition Using SAR Imagery (SAR 영상을 이용한 자동 표적 식별 기법에 대한 연구)

  • Park, Jong-Il;Kim, Kyung-Tae
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.11
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    • pp.1063-1069
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    • 2011
  • NCTR(Non-Cooperative Target Recognition) and ATR(Automatic Target Recognition) are methodologies to identify military targets using radar, optical, and infrared images. Among them, a strategy to recognize ground targets using synthetic aperature radar(SAR) images is called SAR ATR. In general, SAR ATR consists of three sequential stages: detection, discrimination and classification. In this paper, a modification of the polar mapping classifier(PMC) to identify inverse SAR(ISAR) images has been made in order to apply it to SAR ATR. In addition, a preprocessing scheme can mitigate the effect from the clutter, and information on the shadow is employed to improve the classification accuracy.

Extraction of Hydrodynamic Model Parameters for GaAs Using the Monte Carlo Method (Monte Carlo Method에 의한 GaAs의 Hydrodynamic Model Parameter의 추출)

  • Park, Seong-Ho;Han, Baik-Hyung
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.3
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    • pp.63-71
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    • 1990
  • The hydrodynamic model parameters for the submicron GaAs simulation are calculated using the Monte Carlo method. $\Gamma$, L-, and X-valleys are included in the conduction band of GaAs, and polar optic phonon, acoustic phonon, equivalent intervalley, non-equivalent intervalley, ionized impurity, and piezoelectric scattering are taken into account. The velocity-electric field strength curve obtained in this paper is in good agreement with experimental one. We present the results in tabular form so that other participants can make use of them to simulate the submicron GaAs devices by the hydrodynamic model.

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A Study on Iris Recognition by Iris Feature Extraction from Polar Coordinate Circular Iris Region (극 좌표계 원형 홍채영상에서의 특징 검출에 의한 홍채인식 연구)

  • Jeong, Dae-Sik;Park, Kang-Ryoung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.3
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    • pp.48-60
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    • 2007
  • In previous researches for iris feature extraction, they transform a original iris image into rectangular one by stretching and interpolation, which causes the distortion of iris patterns. Consequently, it reduce iris recognition accuracy. So we are propose the method that extracts iris feature by using polar coordinates without distortion of iris patterns. Our proposed method has three strengths compared with previous researches. First, we extract iris feature directly from polar coordinate circular iris image. Though it requires a little more processing time, there is no degradation of accuracy for iris recognition and we compares the recognition performance of polar coordinate to rectangular type using by Hamming Distance, Cosine Distance and Euclidean Distance. Second, in general, the center position of pupil is different from that of iris due to camera angle, head position and gaze direction of user. So, we propose the method of iris feature detection based on polar coordinate circular iris region, which uses pupil and iris position and radius at the same time. Third, we overcome override point from iris patterns by using polar coordinates circular method. each overlapped point would be extracted from the same position of iris region. To overcome such problem, we modify Gabor filter's size and frequency on first track in order to consider low frequency iris patterns caused by overlapped points. Experimental results showed that EER is 0.29%, d' is 5,9 and EER is 0.16%, d' is 6,4 in case of using conventional rectangular image and proposed method, respectively.

Assessment of Non-market Value of Dokdo (독도의 비시장적 가치 평가)

  • Yoo, Seung-Hoon;Lee, Joo-Suk;Chung, Young-Keun
    • Ocean and Polar Research
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    • v.33 no.3
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    • pp.223-233
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    • 2011
  • The Korean government has acknowledged the importance of Dokdo Island and has consequently taken various measures for the effective management of it. There has, however, been little quantitative information about the value of Dokdo Island and this study, therefore, attempts to assess the Islands non-market value. To this end, this study estimated the non-market value by MAUT/CVM. The non-market value estimated by MAUT/CVM includes historic value, military value, ecological value, and geological value. According to the results, the values calculated by the price in market is about 10.37 trillion won and the values estimated by MAUT/CVM is about 1.72 trillion won annually.

Granulosicoccaceae fam. nov., to Include Granulosicoccus antarcticus gen. nov., sp. nov., a Non-phototrophic, Obligately Aerobic Chemoheterotroph in the Order Chromatiales, Isolated from Antarctic Seawater

  • Lee, Ki-Young;Lee, Hong-Kum;Choi, Tae-Hwan;Kim, Kyung-Mi;Cho, Jang-Cheon
    • Journal of Microbiology and Biotechnology
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    • v.17 no.9
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    • pp.1483-1490
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    • 2007
  • A Gram-negative, motile by tuft flagella, obligately aerobic chemoorganoheterotrophic, sphere-form bacterium, designated $IMCC3135^T$, was isolated from the Antarctic surface seawater of King George Island, West Antarctica. The strain was mesophilic, neutrophilic, and requiring NaCl for growth, but neither halophilic nor halotolerant. The 16S rRNA gene sequence analysis indicated that the strain was most closely related to genera of the order Chromatiales in the class Gammaproteobacteria. The most closely related genera showed less than 90% 16S rRNA gene sequence similarity and included Thioalkalispira (89.9%), Thioalkalivibrio (88.0%-89.5%), Ectothiorhodospira (87.9%-89.3%), Chromatium (88.3%-88.9%), and Lamprocystis (87.7%-88.9%), which represent three different families of the order Chromatiales. Phylogenetic analyses showed that this Antarctic strain represented a distinct phylogenetic lineage in the order Chromatiales and could not be assigned to any of the defined families in the order. Phenotypic characteristics, including primarily non-phototrophic, non-alkaliphilic, non-halophilic, and obligately aerobic chemoheterotrophic properties, differentiated the strain from other related genera. The very low sequence similarities (<90%) and distant relationships between the strain and members of the order suggested that the strain merited classification as a novel genus within a novel family in the order Chromatiales. On the basis of these taxonomic traits, a novel genus and species is proposed, Granulosicoccus antarcticus gen. nov., sp. nov., in a new family Granulosicoccaceae fam. nov. Strain $IMCC3135^T\;(=KCCM42676^T=NBRC\;102684^T)$ is the type strain of Granulosicoccus antarcticus.

Long-term Statistical Analysis of the Simultaneity of Forbush Decrease Events at Middle Latitudes

  • Lee, Seongsuk;Oh, Suyeon;Yi, Yu;Evenson, Paul;Jee, Geonhwa;Choi, Hwajin
    • Journal of Astronomy and Space Sciences
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    • v.32 no.1
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    • pp.33-38
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    • 2015
  • Forbush Decreases (FD) are transient, sudden reductions of cosmic ray (CR) intensity lasting a few days, to a week. Such events are observed globally using ground neutron monitors (NMs). Most studies of FD events indicate that an FD event is observed simultaneously at NM stations located all over the Earth. However, using statistical analysis, previous researchers verified that while FD events could occur simultaneously, in some cases, FD events could occur non-simultaneously. Previous studies confirmed the statistical reality of non-simultaneous FD events and the mechanism by which they occur, using data from high-latitude and middle-latitude NM stations. In this study, we used long-term data (1971-2006) from middle-latitude NM stations (Irkutsk, Climax, and Jungfraujoch) to enhance statistical reliability. According to the results from this analysis, the variation of cosmic ray intensity during the main phase, is larger (statistically significant) for simultaneous FD events, than for non-simultaneous ones. Moreover, the distribution of main-phase-onset time shows differences that are statistically significant. While the onset times for the simultaneous FDs are distributed evenly over 24-hour intervals (day and night), those of non-simultaneous FDs are mostly distributed over 12-hour intervals, in daytime. Thus, the existence of the two kinds of FD events, according to differences in their statistical properties, were verified based on data from middle-latitude NM stations.

Evaluation of some indigenous plant extracts for antiimplantation activity in albino rats

  • Pateel, Mallikarjun;Sharanabasappa, Sharanabasappa;Malashetty, Viajykumar B;Patil, Saraswati B;A, Veeranagoud
    • Advances in Traditional Medicine
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    • v.5 no.4
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    • pp.347-351
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    • 2005
  • In the present investigation twelve indigenous medicinal plants have been screened for their antiimplantation activity in albino rats. The plant material was subjected for soxhlation successively and separately from non-polar solvents to polar solvents i.e., petroleum ether benzene and ethanol. Out of these three extracts the petroleum ether extract of seeds of Citrus medica, aerial part of Oxalis corniculata and Tinospora cardifolia have showed maximum antiimplantation activity. Ethanol extract of leaves of Cardiospermum helicacabum, roots of Echinops echinatus, leaves of Melia azedarach, seeds of Momordica charantia and bark of Terminalia bellirica have shown maximum antiimplantation activity amongst the three extracts of each plant material screened. Though all the three extracts of seeds of Annona squamosa and leaves of Zizyphus jujube screened for antiimplantation activity, no extract has showed any loss in implantation. The details of the results obtained are discussed.

A Study on the Analysis of Volatile Flavour of Kimchee (김치 휘발성 향기성분의 분석 방법에 관한 연구)

  • Hawer, Wooderck S.
    • Analytical Science and Technology
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    • v.7 no.1
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    • pp.125-132
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    • 1994
  • Flavours in kimchee are the result of unique combination of various sugars, organic acids and amino acids as well as various volatile organic compounds including sulfur-containing compounds, terpenes, alcohols, and some volatile organic acids. In the experiment for the flavour extracting methods, dynamic headspace(DHS) is more effective for collection of volatile flavour than simultaneous distillation extraction(SDE). The best polarity available at the moment is 5% phenyl methyl poly-siloxane which will separate non-polar, intermediate and polar components with good resolution.

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