• Title/Summary/Keyword: sampling points

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A Numerical Study of Low Grazing Angle Backscattering from Random Rough Surfaces (不規則 粗面에서 저입사각 후방산란에 관한 수치해석)

  • Kwang-Yeol Yoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.6
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    • pp.590-598
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    • 2002
  • We have numerically analyzed the electromagnetic wave scattering from randomly rough dielectric surfaces by using the finite volume time domain (FVTD) method. We have then shown that the present method yields a reasonable solution even at low-grazing angle (LGA). It should be noted that the number of sampling points per wavelength should be increased when more accurate numerical results are required, which fact makes the computer simulation impossible at LGA for a stable result. However, when the extrapolation is used for calculating the scattered field, an accurate result can be estimated. If we want to obtain the ratio of backscattering between the horizontal and vertical polarization, we do not need the large number of sampling points. The results are compared with the experimental data.

Characterization of Illegally Dumped Wastes in Riversides of Nakdong River (낙동강 중류 고수부지내 매립폐기물 특성 연구)

  • Kim, Youngsug;Choi, Boram;Lee, Wontae;Kang, Sungwon;Ahn, Kwangho;Lee, Taeyoon
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.9
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    • pp.21-25
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    • 2011
  • This study was performed to evaluate characteristics of illegally dumped wastes in the riversides of Nakdong river found during dredging of Nakdong river. Precise classification of the wastes found in the riversides is essential to proper treatment of the wastes. We tried to determine whether these wastes contained toxic compounds and stabilized. Wastes were found at 27 sampling points out of 159 segments investigated and these wastes were not classified as toxic wastes. In addition, clay soils were found at 60 sampling points, and these soils were not classified as wastes. Thus, these soils are thought to be recycled as construction materials. Some samples were not stabilized, which means biodegradation was still progressed in these areas.

Implementation of a Vehicle Speed Measurement System Using Image Processing (영상처리에 의한 차량속도 계측 시스템 구현)

  • Park Hyeong taek;Yun Tae won;Hwang Byong won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4C
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    • pp.276-282
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    • 2005
  • These studies developed system as well as its algorithm which can measure traffic flow and vehicle speed on the highway as well as road by using industrial television(ITV) system. This algorithm used the real time processing of dynamic images. The processing algorithm of dynamic images is developed and proved its validity by frame grabber. Frame grabber can process the information of a small number of sample points only instead of the whole pixel of the images. In the techniques of this algorithm, we made approximate contour of vehicle by allocating sampling points in cross-direction of image, and recognized top of contour of vehicle. Applying these technique, we measured the number of passing vehicles of one lane as well as multilane. Speed of each vehicle is measured by computing the time difference between a pair of sample points on two sample Points lines.

Measurement Algorithm of Vehicle Speed Using Real-Time Image Processing (영상의 실시간 처리에 의한 차량 속도의 계측 알고리즘)

  • Seo, Jeong-Goo;Lee, Jeong-Goo;Yun, Tae-Won;Hwang, Byong-Won
    • Journal of Advanced Navigation Technology
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    • v.9 no.1
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    • pp.10-18
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    • 2005
  • These studies developed system as well as its algorithm which can measure traffic flow and vehicle speed on the highway as well as road by using industrial television(ITV) system. This algorithm used the real time processing of dynamic images. The processing algorithm of dynamic images is developed and proved its validity by frame grabber. Frame grabber can process the information of a small number of sample points only instead of the whole pixel of the images. In the techniques of this algorithm, we made approximate contour of vehicle by allocating sampling points in cross-direction of image, and recognized top of contour of vehicle. Applying these technique, we measured the number of passing vehicles of one lane as well as multilane. Speed of each vehicle is measured by computing the time difference between a pair of sample points on two sample points lines.

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GEOMETRY OF SATELLITE IMAGES - CALIBRATION AND MATHEMATICAL MODELS

  • JACOBSEN KARSTEN
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.182-185
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    • 2005
  • Satellite cameras are calibrated before launch in detail and in general, but it cannot be guaranteed that the geometry is not changing during launch and caused by thermal influence of the sun in the orbit. Modem satellite imaging systems are based on CCD-line sensors. Because of the required high sampling rate the length of used CCD-lines is limited. For reaching a sufficient swath width, some CCD-lines are combined to a longer virtual CCD-line. The images generated by the individual CCD-lines do overlap slightly and so they can be shifted in x- and y-direction in relation to a chosen reference image just based on tie points. For the alignment and difference in scale, control points are required. The resulting virtual image has only negligible errors in areas with very large difference in height caused by the difference in the location of the projection centers. Color images can be related to the joint panchromatic scenes just based on tie points. Pan-sharpened images may show only small color shifts in very mountainous areas and for moving objects. The direct sensor orientation has to be calibrated based on control points. Discrepancies in horizontal shift can only be separated from attitude discrepancies with a good three-dimensional control point distribution. For such a calibration a program based on geometric reconstruction of the sensor orientation is required. The approximations by 3D-affine transformation or direct linear transformation (DL n cannot be used. These methods do have also disadvantages for standard sensor orientation. The image orientation by geometric reconstruction can be improved by self calibration with additional parameters for the analysis and compensation of remaining systematic effects for example caused by a not linear CCD-line. The determined sensor geometry can be used for the generation? of rational polynomial coefficients, describing the sensor geometry by relations of polynomials of the ground coordinates X, Y and Z.

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Observations of Variations in Soil Organic Carbon and Carbon Dioxide in the Constructed Wetland at Goheung Bay (고흥만 인공습지의 토양유기탄소와 이산화탄소 변동 관측)

  • Kang, Dong-Hwan;Kim, Sung-Soo;Kwon, Byung-Hyuk;Kim, Il-Kyu
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.1
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    • pp.58-67
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    • 2008
  • Seasonal variations in carbon dioxide in the air and soil organic carbon in the sediments were monitored at the constructed wetland formed by reclamation work at Goheung Bay. Sediment sampling in the constructed wetland and carbon dioxide measurement in the air were conducted on June 16 and August 23, 2007. Sediments in the constructed wetland were sampled at 11 different points (June 16) and 14 points (August 23), while carbon dioxide in the air was measured at 13 points (June 16) and 15 points (August 23). Water content and organic carbon in the sampled sediments were analyzed in the laboratory. Water content of the sediments was higher than that of general soil, and the variation between June and August was not evident. The amounts of organic carbons in the sediments sampled on August 23 were higher than those sampled on June 16. Also, there was more organic carbon in the sediments sampled at the field of reeds than in the pure wetland area. Daily maximum variation in carbon dioxide in the air was higher on June 16, but the amount of carbon dioxide in the air was greater on August 23. The results of the study suggest that organic carbon in the sediments and carbon dioxide in the air were greater in summer (August 23) than in spring season (June 16) in the constructed wetland at Goheung Bay.

Speciation and Leaching Potential of Heavy Metals in Sediments of Nakdong River (낙동강 퇴적물 내 중금속 존재 형태 및 용출 가능성)

  • Hwang, Kyung-Yup;Park, Seong-Yeol;Baek, Won Suk;Jung, Je-Ho;Kim, Young-Hun;Shin, Won Sik;Lee, Nam Joo;Hwang, Inseong
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.1
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    • pp.113-122
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    • 2007
  • Experimental studies were performed to investigate speciation and leaching potential of heavy metals(Cu, Cd, Pb Zn, Ni) in ten sediment samples collected from Nakdong River. Acid Volatile Sulfide (AVS) and Simultaneously Extractable Metals (SEM) measurements were used to estimate heavy metals that can be leached under anaerobic conditions. Sequential Extraction Procedure (SEP) and Toxicity Characteristic Leaching Procedure (TCLP) were used to characterize speciation and leaching potential of heavy metals under aerobic conditions. The results show that total concentrations of Cu, Zn and Ni were relatively high in the sediments from points Seongseo industrial complex stream (upper stream) (D), Seongseo industrial complex stream (midstream) (E), Dalseo stream (F), and Nakdong river estuary (J), and that Cd concentrations were higher in all sampling points except for Goriung Bridge (G) and Soosan Bridge (H). SEM and AVS analyses reveal that samples from points Ilsun Bridge (A), Namgumi Bridge (C), and Soosan Bridge (H) have potential of heavy metals leaching, although leachable concentrations are relatively low. The leaching potential of heavy metals in other points was low because of higher concentrations of AVS than SEM. SEP results show that more than 50% of Cu, Zn and Ni were present in residual fraction, which means these metals are less amenable to leaching in anaerobic conditions. On the other hand, more than 50% of Pb and Cd were extracted during the first through third step of the SEP, which means substantial fraction of these metals can be leached upon changing of redox conditions. TCLP tests predict that leaching potential of heavy metals was generally low, which is consistent with the results obtained by AVS and SEM measurements.

Preparation of Ice at Home and Consumer's Demand for Auto Icemaker in Refrigerator (가정에서의 냉장고를 이용한 제빙 실태와 제빙 설비 개선에 대한 요구도 조사)

  • Lee, Young-Mee;Jang, Jeong-Ock
    • Journal of the East Asian Society of Dietary Life
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    • v.7 no.2
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    • pp.211-220
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    • 1997
  • This study was investigated about preparation of ice at home and developing points which met consumer's demand that was focused on auto icemaker. According to purposive quota sampling method, residences in Seoul and Kyunggi-do area were selected and interviewed by trained interviewer at August 1995. The results were as follows: 66.3% of respondent usually prepared ice in ice-making container of refrigerator and used when they needed. 85% of them used ice in summer and seldomly used in other seasons. Boiling water with barley was major drinking water(45.6%), and broiled or purified tap water was used to make ice(38.6%) commonly. Numbers of ice-making container were two(66.0%). Above 50% of respondents replied that they felt off-flavor in ice usually. After felt off-flavor, 54.7% of respondent threw away the ice, some of them used off-flavored ice after treatment to washing with water. 64.9% of respondents thought that the origins of off-flavor was the flavor of refrigerator itself. The consumer's expectation of developing points were as follows. The most priority of developing points was to make ice quickly, the next was to develop auto ice maker and ice storage container, to make different size of ice. Less expected points were to make more clear ice and large volume of ice in one time. The recognition about auto ice maker was slightly low(35% of respondents), but 67% of them wanted to develop auto ice maker.

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SAVITZKY-GOLAY DERIVATIVES : A SYSTEMATIC APPROACH TO REMOVING VARIABILITY BEFORE APPLYING CHEMOMETRICS

  • Hopkins, David W.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1041-1041
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    • 2001
  • Removal of variability in spectra data before the application of chemometric modeling will generally result in simpler (and presumably more robust) models. Particularly for sparsely sampled data, such as typically encountered in diode array instruments, the use of Savitzky-Golay (S-G) derivatives offers an effective method to remove effects of shifting baselines and sloping or curving apparent baselines often observed with scattering samples. The application of these convolution functions is equivalent to fitting a selected polynomial to a number of points in the spectrum, usually 5 to 25 points. The value of the polynomial evaluated at its mid-point, or its derivative, is taken as the (smoothed) spectrum or its derivative at the mid-point of the wavelength window. The process is continued for successive windows along the spectrum. The original paper, published in 1964 [1] presented these convolution functions as integers to be used as multipliers for the spectral values at equal intervals in the window, with a normalization integer to divide the sum of the products, to determine the result for each point. Steinier et al. [2] published corrections to errors in the original presentation [1], and a vector formulation for obtaining the coefficients. The actual selection of the degree of polynomial and number of points in the window determines whether closely situated bands and shoulders are resolved in the derivatives. Furthermore, the actual noise reduction in the derivatives may be estimated from the square root of the sums of the coefficients, divided by the NORM value. A simple technique to evaluate the actual convolution factors employed in the calculation by the software will be presented. It has been found that some software packages do not properly account for the sampling interval of the spectral data (Equation Ⅶ in [1]). While this is not a problem in the construction and implementation of chemometric models, it may be noticed in comparing models at differing spectral resolutions. Also, the effects on parameters of PLS models of choosing various polynomials and numbers of points in the window will be presented.

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The Odd Pair Family's Dietary management in rural, Korea - Comparison with the Pair Family - (농촌거주 외짝가족의 식생활관리 -부부가족과의 비교-)

  • Rhie Seung Gyo;Chung Kum Ju;Won Hyang Rye
    • The Korean Journal of Community Living Science
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    • v.16 no.1
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    • pp.89-103
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    • 2005
  • Recently the rural Korea has been remarkedly changed of family and social value in accordance with the development of industry. The lower economic class made by social economic growth is widespread with increasing aged, specially odd pair family in rural. The purpose of this study was to investigate to help and keep improve health of rural lower economic class, family system by comparing and analyzing the dietary management, between pair and odd pair family, and to get the data helpful the right guidance for rural. The subjects 1870 collected in 9 provinces by sampling with probability proportional to size (PPS). Questionnaire about dietary habit, food cultivation, production and preservation survey was conducted by trained interviewers. The main results were as follows : 1) The characteristics of odd pair families, head of household was female(77%), over 65 years(84.9%), small family(1.76 persons) and lower education(male 7.5 years, female 3.1 years) status. 2) As the states of diets of odd pair family, having breakfast(87.1 %) but one or two kinds of side dishes(31.3 %) only possible to guess lower status of food intake balance. Nutritional supplements(21. 7 %) was lower than that of paired family. 3) The aspects of dietary habit of odd pair family, no instant foods(70.7%), no snack(38.4%) no dine out(69.2%) were common. 4) Dietary habit scores were 7.78 points of odd pair family compared 8.34 points of paired family. 5) Food purchase place of odd pair family was market(44.2%) but super-market(42.7%) of paired family. 6)In odd pair family, seldom traditional dish preparation(62.0%) but prepared winter kimchi(81.9%), comparing seldom traditional dish(38.6%) and winter kimchi(96.4%) in paired family. 7)The food cultivation state was surveyed, pepper( 42.2 %) and chinese cabbage( 43.9 %) were consumed after cultivation, but sesame(59.4%), bean sprout(90.2%), tofu(92.8%) and egg(93.3%) were consumed by purchase in odd pair family.8) Food cultivation score of odd pair family was 2.98/12points significantly lower than 4.50/12 points of paired family(p<0.01). 9) At the status of fermentation food production in odd pair family, Duenjang(72.1 %) and Gochujang(69.7%) Kanjang(68.3%) Kimchi(82.1 %) and Meju(68.3%) were high rate of production, but more frequently producted in pair family. 10) The score of fermentation food production of odd pair family was 8.57/12points but significantly lower than 10.24/12 points of pair family(p<0.0001). 11) Food preservation score 0.48/6 points in odd pair family was not significantly different than that of pair family(1.07/6points).

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