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Laver Farm Feature Extraction From Landsat ETM+ Using Independent Component Analysis

  • Han J. G.;Yeon Y. K.;Chi K. H.;Hwang J. H.
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.359-362
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    • 2004
  • In multi-dimensional image, ICA-based feature extraction algorithm, which is proposed in this paper, is for the purpose of detecting target feature about pixel assumed as a linear mixed spectrum sphere, which is consisted of each different type of material object (target feature and background feature) in spectrum sphere of reflectance of each pixel. Landsat ETM+ satellite image is consisted of multi-dimensional data structure and, there is target feature, which is purposed to extract and various background image is mixed. In this paper, in order to eliminate background features (tidal flat, seawater and etc) around target feature (laver farm) effectively, pixel spectrum sphere of target feature is projected onto the orthogonal spectrum sphere of background feature. The rest amount of spectrum sphere of target feature in the pixel can be presumed to remove spectrum sphere of background feature. In order to make sure the excellence of feature extraction method based on ICA, which is proposed in this paper, laver farm feature extraction from Landsat ETM+ satellite image is applied. Also, In the side of feature extraction accuracy and the noise level, which is still remaining not to remove after feature extraction, we have conducted a comparing test with traditionally most popular method, maximum-likelihood. As a consequence, the proposed method from this paper can effectively eliminate background features around mixed spectrum sphere to extract target feature. So, we found that it had excellent detection efficiency.

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지하수의 라듐/라돈 동시측정을 위한 백그라운드 감마선 제어

  • Lee Gil-Yong;Yun Yun-Yeol;Jo Su-Yeong;Kim Yong-Je
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2005.04a
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    • pp.308-311
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    • 2005
  • [ $^{222}Rn\;and\;^{226}Ra$ ] in groundwater were determined simultaneously using a gamma-spectroscopy. A nitrogen flushing equipment has been used for elimination and stabilization of high and unstable background activity due to the radon and its progenies in counting shield and room. The aim of present work was to control the background activity for simultaneous measurement of radium$(^{226}Ra)$ and radon$(^{222}Rn)$ in groundwater using a gamma-spectrometry. Background activity was about 1.0dps and the standard deviation was about 50%, The background activity could be minimized using nitrogen flushing equipment in the range of 0.1 to 0.5 and the RSD was about 5% at the experimental condition. The detection limit of $^{222}Rn\;and\;^{226}Ra$ in groundwater was 0.5dps/L in the background control method. In most groundwater used in the work, radon activity was more than the detection limit. However, radium activity in some groundwater was less than the detection limit. If the low level radium in groundwater must be measured, preconcentration process such as concentration should be performed before measuring the groundwater.

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AUTONOMIC MECHANISMS OF AN ACUTE STRESS RESPONSE DURING WORD RECOGNITION TASK PERFORMANCE WITH INTENSE NOISE BACKGROUND (백색소음하의 단어재인검사 수행에 따른 자율신경계 스트레스 반응)

  • ;;;Estate Sokhadze
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1999.03a
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    • pp.127-132
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    • 1999
  • Cardiovascular, respiratory and electrodermal responses to acute stress episodes modeled by combined presentation of intense white noise and performance of word recognition task with noise background were studied in 15 college students. Experimental procedure consisted in sessions with white noise, word recognition task presentation with noise background and test with noise background. Recorded physiological variables were analyzed in terms of their sensitivity to detect activation of sympathetic and parasympathetic branches of autonomic nervous system and thus reflect autonomic arousal level during shout-term stress-inducing experimental manipulations. It was shown that performance of effortful mental task with noise background elicited significant physiological responses typical for active coping behavior, namely electrodermal arousal and increased cardiovascular activity. this response profile was more profound as compared to white noise only or attending task in noise background. However, all physiological responses were mostly phasic, without long-term tonic changes, since almost all variables recovered to their initial baseline levels, suggesting that dominant autonomic mechanisms in transient acute stress episodes were of parasympathetic nature (withdrawal in stress with subsequent activation in restoration period), while sympathetic contribution was not long-lasting. Nevertheless, increased number of stressors and their longer exposure may result in higher profile of tonic sympathetic arousal and reduced functional role of vagal mechanisms in autonomic balance regulation.

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A Comparative Analysis of Whole Blood Cadmium by Atomic Absorption Spectrophotometry with a Graphite Furnace (흑연로 원자흡수분광법에 의한 혈액중 카드뮴 정량분석)

  • Park, Jong An;Oh, Hye Jeong;Lee, Jong Hwa
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.6 no.2
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    • pp.301-312
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    • 1996
  • This study was performed to search a optimal analyzing method of cadmium in whole-blood. Cadmium was determined by graphite furnace atomic absorption spectrometry(GFAAS). We investigated the effect of ashing temperature on the absorbance of cadmium in a simple dilution(ten-fold) method with triton X-100 and matrix modifier methods treated with $NH_4H_2PO_4$(1 and 3%) and $Pd(NO_3)_2$(0.00l and 0.005%) as matrix modifier. We also compared the reported reference values of standard blood with values resulted from optimal analyzing conditions of this study. In case of a simple dilution method, when ashing temperature was set at $450^{\circ}C$, the absorbance of sample and background were $0.334{\pm}0.012$ and $1.382{\pm}0.245$, respectively. Background level was higher than the value(0.8) that can be corrected by $D_2$ background correction method. As ashing temperature was rised to $500^{\circ}C$, the absorbance of sample and background were $0.178{\pm}0.008$ and $0.711{\pm}0.223$ respectively. The higher ashing temperature($450^{\circ}C-650^{\circ}C$) was, the lower the absorbance of sample was. In case of a matrix modifier method with $NH_4H_2PO_4$(1 and 3%), when ashing temperature was rised from $500^{\circ}C$ to $650^{\circ}C$, the absorbance of sample slightly changed. The absorbances of sample at $600^{\circ}C$ were $0.230{\pm}0.017$ and $0.137{\pm}0.012$, respectively. These values were larger than that of simple dilution method. But the absorbance of background was higher than the level that can be corrected by $D_2$ method. In case of a matrix modifier method with $Pd(NO_3)_2$(0.001 and 0.005%), the absorbance of sample and background were higher than those of other methods and were stable and reproducible. When ashing temperature was over $550^{\circ}C$, the absorbance of sample was significantly decreased. In case of 0.005% $Pd(NO_3)_2$ carbon residue remained in graphite tube affected the absorbance of sample and background. From these results, We propose that in case of a simple dilution(ten-fold) method with triton X-100 ashing temperature must be maintained below $400^{\circ}C$. In order to diminish the absorbance of background, the alternative method is attenuation of injection volume or multiplication of dilution ratio. We recommend $Pd(NO_3)_2$ than $NH_4H_2PO_4$ as a matrix modifier. In case of a matrix modifier method with $Pd(NO_3)_2$ ashing temperature might be maintained below $550^{\circ}C$.

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Analysis on Students Background Factors Influencing to ICT literacy Level of Elementary and Middle School Students (ICT 리터러시 수준에 영향을 미치는 초·중학생의 배경 요인 분석)

  • Ahn, Seonghun
    • The Journal of Korean Association of Computer Education
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    • v.20 no.4
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    • pp.67-75
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    • 2017
  • This study analyzed the impact of ICT usage on elementary and secondary school students on the result of ICT literacy levels for finding out why most of students were 'normal' or 'basic'. As a result, we found out that the learning action, information searching and leisure action of student using ICT had correlation with ICT literacy level. The higher the rate using ICT for learning, information searching and leisure, the higher the ICT literacy level of student. But the higher the rate using ICT for communication, the lower the ICT literacy level of student. Accordingly, we proposed the policy not to increase simply ICT using of student, but to teach how to use ICT for learning and information searching.

A Study on the Key Competencies of The married female immigrants at work (취업한 여성결혼이민자들의 직업기초능력에 관한 연구)

  • Park, Sin-Young;Yi, Byung-Jun
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.4
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    • pp.973-990
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    • 2013
  • On this study, the survey was conducted for the married female immigrants at work living in the district of Pusan, Changwon and Gimhae in order to analyze the level of the key competencies based on the differences of their ages, their final educational background, the period of their staying in Korea, their Korean language competence, jobs and the employment status in their native countries. As the result of the analysis, firstly, depending on their Korean language competence and jobs, there were meaningful differences among the groups in the aspects of the nine key competencies including communication, numeracy, problem solving, self-management and development, resource use, human relationship, information, technology, and organization skills, with the statistical significance level of .05. Secondly, depending on their final educational background, there were meaningful differences among the groups in the other aspects of eight key competencies except problem solving, with the statistical significance level of .05. Thirdly, depending on the employment status in their native countries, there were meaningful differences among the groups in the aspects of the five competencies including communication, numeracy, problem solving, resource use and organizational skills with the statistical significance level of 0.05. Fourthly, depending on the period of staying in Korea, there is difference only in the aspect of communication. Fifthly, depending on their ages, there were no meaningful differences among the groups.

Effect of Variables Affecting the Self-Sufficiency Perceived by Multicultural Famly in Rural Korea (농촌 다문화가족의 자립에 영향을 미치는 변인 연구)

  • Yang, Soon-Mi
    • Journal of Agricultural Extension & Community Development
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    • v.22 no.1
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    • pp.55-67
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    • 2015
  • This study aimed at identifying theirs relative importance and the factors affecting self-sufficiency in rural multicultural families. The major findings that were drawn from this study were as follows : Frist, the difference in the self-sufficiency level of their family perceived between husband and married immigrant women was not significant. But, in the level of self-sufficiency will, the level perceived by the husband was higher than it of the women significantly. Second, the hierarchical regression analysis showed that the age of the women(${\ss}=.31$) affected most significantly the self-sufficiency in rural multicultural families, followed by the labour morale of the women(${\ss}=.25$), labour morale of the husband(${\ss}=.20$), academic background of the husband(${\ss}=.19$), academic background of the women(${\ss}=.12$), spouse support level of the women toward the husband(${\ss}=.12$). Third, as a result of a hierarchical regression analysis, the self-sufficiency will variables had more explanatory power on it than social-demographic and/or social support variables. In conclusion, based on results of this study, several plans improving self-sufficiency of the rural multicultural family were suggested. Findings of this study may be used as a basic material to establish the policy supporting self-sufficiency in rural multicultural families.

An Effective Moving Cast Shadow Removal in Gray Level Video for Intelligent Visual Surveillance (지능 영상 감시를 위한 흑백 영상 데이터에서의 효과적인 이동 투영 음영 제거)

  • Nguyen, Thanh Binh;Chung, Sun-Tae;Cho, Seongwon
    • Journal of Korea Multimedia Society
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    • v.17 no.4
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    • pp.420-432
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    • 2014
  • In detection of moving objects from video sequences, an essential process for intelligent visual surveillance, the cast shadows accompanying moving objects are different from background so that they may be easily extracted as foreground object blobs, which causes errors in localization, segmentation, tracking and classification of objects. Most of the previous research results about moving cast shadow detection and removal usually utilize color information about objects and scenes. In this paper, we proposes a novel cast shadow removal method of moving objects in gray level video data for visual surveillance application. The proposed method utilizes observations about edge patterns in the shadow region in the current frame and the corresponding region in the background scene, and applies Laplacian edge detector to the blob regions in the current frame and the corresponding regions in the background scene. Then, the product of the outcomes of application determines moving object blob pixels from the blob pixels in the foreground mask. The minimal rectangle regions containing all blob pixles classified as moving object pixels are extracted. The proposed method is simple but turns out practically very effective for Adative Gaussian Mixture Model-based object detection of intelligent visual surveillance applications, which is verified through experiments.

A Technique to Minimize Impurity Signal from Blank Rhenium Filaments for Highly Accurate TIMS Measurements of Uranium in Ultra-Trace Levels

  • Park, Jong-Ho;Choi, In-Hee;Song, Kyu-Seok
    • Mass Spectrometry Letters
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    • v.1 no.1
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    • pp.17-20
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    • 2010
  • As background significantly affects measurement accuracy and a detection limit in determination of the trace amounts of uranium, it is necessary to minimize the impurities in the filaments used for thermal ionization mass spectrometry (TIMS). We have varied the degassing condition such as the heating currents and duration times to reduce the backgrounds from the filaments prepared with zone-refined rhenium tape. The most efficient degassing condition of the heating current and the duration time was determined as 3.5 A and 60 min, respectively. The TIMS measurement combined with the isotope dilution mass spectrometry (IDMS) technique showed that the uranium backgrounds were determined to be in a few fg level from blank rhenium filaments. The background minimized filaments were utilized to measure the uranium isotope ratios of a U030 (NIST) standard sample. The excellent agreement of the measurement with the certified isotope ratios showed that the degassing procedure optimized in this study efficiently reduced the impurity signals of uranium from blank rhenium filaments to a negligible level.

X-ray fluorescence spectrum of the block algorithm to apply the interval threshold method using DWT (DWT를 이용한 형광 X-선 스펙트럼의 interval Threshold를 적용하기 위한 블록화 알고리즘)

  • Yang, Sang-Hoon;Lee, Jae-Hwan;Park, Dong-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.5
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    • pp.2291-2297
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    • 2012
  • X-ray fluorescence sprectrum signal include the continuum. XRF analysis the components of material by the amplitude of peaks. XRF remove the noise and background. To remove the noise, we apply the smoothing filter. And background removal methods applied such as SNIP, Morphology, Threshold methods. In this paper, we applied Threshold using DWT. Interval threshold method divide the some blocks in particular levels. We propose the method that is divided the particular level.