• Title/Summary/Keyword: current trace

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The Current Statues and Cause of Dietary Supplement Use in Elite Athletes (우수선수들의 운동영양 보조물 이용 현황과 원인)

  • Kim, Jong-Kyu;Lee, Nam-Ju;Lee, Mi-Sook
    • 한국체육학회지인문사회과학편
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    • v.51 no.3
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    • pp.427-435
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    • 2012
  • The purpose of this review study is to examine current status of dietary supplement use to enhance athletic performance capacity in elite athletes based upon anti-doping education, sports type, athletic performance capacity, gender, and age. Several previous review studies have focused on the biochemistry characteristics and intake incidence of dietary supplements and those studies have not showed enough evidence of the reason why elite athletes usually take dietary supplements. Anti-doping education may increase the incidence of dietary supplement use in elite athletes because of increasing expertise of dietary supplements. It would be expected that increased incidence of long-term dietary supplement use may induce positive effects on the body having potential effects on athletic performance capacity, although a trace of nutrients may not directly effect on the outcome of the game. Moreover, it seems that the difference of dietary supplement use based upon gender and age may come from sports type and the difference of dietary supplement intake reason may come from health and body condition maintenance rather than athletic performance capacity when considering dietary supplement use items based upon intake reasons. Most elite athletes consume at least over 2 dietary supplement items in a long period of time rather than 1 dietary supplement item in a short period of time; however, the scientific evidence of dietary supplement use seems to be insufficient. Therefore, further experimental approach studies concerning dietary supplement effects would be needed.

Introduction of a New Method for Total Organic Carbon and Total Nitrogen Stable Isotope Analysis of Dissolved Organic Matter in Aquatic Environments (수환경 내 용존성 유기물질의 총 유기탄소 및 총 질소 안정동위원소 신규 분석법 소개)

  • Si-yeong Park;Heeju Choi;Seoyeon Hong;Bo Ra Lim;Seoyeong Choi;Eun-Mi Kim;Yujeong Huh;Soohyung Lee;Min-Seob Kim
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.339-347
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    • 2023
  • Dissolved organic matter (DOM) is a key component in the biogeochemical cycling in freshwater ecosystem. However, it has been rarely explored, particularly complex river watershed dominated by natural and anthropogenic sources, such as various effluent facility and livestock. The current research developed a new analytical method for TOC/TN (Total Organic Carbon/Total Nitrogen) stable isotope ratio, and distinguish DOM source using stable isotope value (δ13C-DOC) and spectroscopic indices (fluorescence index [FI] and biological index [BIX]). The TOC/TN-IR/MS analytical system was optimized and precision and accuracy were secured using two international standards (IAEA-600 Caffein, IAEA-CH-6 Sucrose). As a result of controlling the instrumental conditions to enable TOC stable isotope analysis even in low-concentration environmental samples (<1 mgC L-1), the minimum detection limit was improved. The 12 potential DOM source were collected from watershed, which includes top-soils, groundwater, plant group (fallen leaves, riparian plants, suspended algae) and effluent group (pig and cow livestock, agricultural land, urban, industry facility, swine facility and wastewater treatment facilities). As a result of comparing characteristics between 12 sources using spectroscopic indices and δ13C-DOC values, it were divided into four groups according to their characteristics as a respective DOM sources. The current study established the TOC/TN stable isotope analyses system for the first time in Korea, and found that spectroscopic indices and δ13C-DOC are very useful tool to trace the origin of organic matter in the aquatic environments through library database.

Studies on the Water Quality of Urban Streams in Daegu City (대구시(大邱市) 도시하천(都市河川)의 수질조사(水質調査) 연구(硏究))

  • Lee, Jyung Jae;Park, Byoung Yoon;Choi, Jyung
    • Current Research on Agriculture and Life Sciences
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    • v.6
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    • pp.99-104
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    • 1988
  • Water polution status of urban streams in Daegu city were observed to provide the basic information for the effective purification of urban sewage and the conservation of Keumho river. Periodically, pH, DO, COD, nitrate and phosphate of water were investigated at Yee cheon, B$\ddot{o}$m$\ddot{o}$ cheon, Chilsung cheon, Dalseo cheon and Kongdan cheon. The results were as follows. 1) The ranges of average values of analyzed components for 12 months at six sampling sites were pH 7.3-8.2, DO trace-6.5ppm, COD 20.4-116.9ppm, T-N 23.2-31.7ppm, $NH_4$-N 18.3-27.7ppm, $NO_2$-N 0.08-1.89ppm, $NO_3$-N 0.19-1.51ppm, $PO_4$-P 2.50-17.28ppm. 2) At Kongdan cheon, the most heavily polluted site, average values of components were pH 8.2, DO trace, COD 116.9ppm, T-N 23.2ppm, $NH_4$-N 18.3ppm, $NO_2$-N 1.89ppm, $NO_3$-N 1.51ppm, $PO_4$-P 17.28ppm. 3) The values of pH, DO, COD, T-N and $NH_4$-N at winter urban streams were higher than those at summer urban streams. And the values of $NO_2$-N and $PO_4$-P were more or less higher at summer urban streams.

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Introduction of Kjeldahl Digestion Method for Nitrogen Stable Isotope Analysis (δ15N-NO3 and δ15NNH4) and Case Study for Tracing Nitrogen Source (Kjeldahl 증류법을 활용한 질산성-질소 및 암모니아성-질소 안정동위원소비 분석 및 질소오염원 추적 사례 연구)

  • Kim, Min-Seob;Park, Tae-Jin;Yoon, Suk-Hee;Lim, Bo-La;Shin, Kyung-Hoon;Kwon, Oh-Sang;Lee, Won-Seok
    • Korean Journal of Ecology and Environment
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    • v.48 no.3
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    • pp.147-152
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    • 2015
  • Nitrogen (N) loading from domestic, agricultural and industrial sources can lead to excessive growth of macrophytes or phytoplankton in aquatic environment. Many studies have used nitrogen stable isotope ratios to identify anthropogenic nitrogen in aquatic systems as a useful method for studying nitrogen cycle. In this study to evaluate the precision and accuracy of Kjeldahl processes, two reference materials (IAEA-NO-3, N-1) were analyzed repeatedly. Measured the ${\delta}^{15}N-NO_3$ and ${\delta}^{15}N-NH_4$ values of IAEA-NO-3 and IAEA-N-1 were $4.7{\pm}0.2$‰ and $0.4{\pm}0.3$‰, respectively, which are within recommended values of analytical uncertainties. Also, we investigated spatial patterns of ${\delta}^{15}N-NO_3$ and ${\delta}^{15}N-NH_4$ in effluent plumes from a waste water treatment plant in Han River, Korea. ${\delta}^{15}N-NO_3$ and ${\delta}^{15}N-NH_4$ values are enriched at downstream areas of water treatment plant suggesting that dissolved nitrogen in effluent plumes should be one of the main N sources in those areas. The current study clarifies the reliability of Kjeldahl analytical method and the usefulness of stable isotopic techniques to trace the contamination source of dissolved nitrogen such as nitrate and ammonia.

Chemical Age Dating of Zircon and Monazite by E1ectron Microprobe (전자현미분석기를 이용한 저어콘 및 모나자이트의 화학적 연대 측정법)

  • 이석훈
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.179-189
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    • 2001
  • The determination of trace concentration of U, Th and Pb was carried out for chemical dating of zircon and monazite by electron microprobe. Detection limit and error range should be considered to measure characteristic X-rays of M-line from those minerals, which are low in the ionization of atom and low peak intensity in the spectrum. The element of U, Th and Pb were simultaneously measured with 3 spectrometers equipped with PET crystal to reduce a total counting time and error due to drift of instrumental operating condition. Detection limit could be improved from increase of the peak/background ratio through adjusting pulse height analyzer about 1000 mv baseline. Under permissible maximum analytical conditions, theoretical detection limit of U, Th and Pb is down to 30 ppm (99% confidence level). The analytical result was maintained at a relative error $\pm$10% ($2{\sigma}$) in 800 ppm Pb, $\pm$5% ($2{\sigma}$) in 2330 ppm U and $\pm$10% ($2{\sigma}$) in dating from a single measurement of zircon at 15 keV and 100 nA. However, for the precise dating of zircon and monazite, if it is considered a 3 $\mu\textrm{m}$ spatial resolution, <100 ppm ($3{\sigma}$) detection limit and <$\pm$10% ($2{\sigma}$) relative error, optimum analytical conditions are given as 15~20 keV accelerating voltage, 100~200 nA beam current and 300~1200 sec total counting time. To reduce material damage by high current, there is need to be up to 3~5 $\mu\textrm{m}$ of electron beam diameter, or to use arithmetic average of multiple measuring at a shorter counting time. A younger or relatively low concentration rocks can be dated chemically by lower detection limit and improved precision resulted from increase of current and measuring time.

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2-D/3-D Seismic Data Acquisition and Quality Control for Gas Hydrate Exploration in the Ulleung Basin (울릉분지 가스하이드레이트 2/3차원 탄성파 탐사자료 취득 및 품질관리)

  • Koo, Nam-Hyung;Kim, Won-Sik;Kim, Byoung-Yeop;Cheong, Snons;Kim, Young-Jun;Yoo, Dong-Geun;Lee, Ho-Young;Park, Keun-Pil
    • Geophysics and Geophysical Exploration
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    • v.11 no.2
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    • pp.127-136
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    • 2008
  • To identify the potential area of gas hydrate in the Ulleung Basin, 2-D and 3-D seismic surveys using R/V Tamhae II were conducted in 2005 and 2006. Seismic survey equipment consisted of navigation system, recording system, streamer cable and air-gun source. For reliable velocity analysis in a deep sea area where water depths are mostly greater than 1,000 m and the target depth is up to about 500 msec interval below the seafloor, 3-km-long streamer and 1,035 $in^3$ tuned air-gun array were used. During the survey, a suite of quality control operations including source signature analysis, 2-D brute stack, RMS noise analysis and FK analysis were performed. The source signature was calculated to verify its conformity to quality specification and the gun dropout test was carried out to examine signature changes due to a single air gun's failure. From the online quality analysis, we could conclude that the overall data quality was very good even though some seismic data were affected by swell noise, parity error, spike noise and current rip noise. Especially, by checking the result of data quality enhancement using FK filtering and missing trace restoration technique for the 3-D seismic data inevitably contaminated with current rip noises, the acquired data were accepted and the field survey could be conducted continuously. Even in survey areas where the acquired data would be unsuitable for quality specification, the marine seismic survey efficiency could be improved by showing the possibility of noise suppression through onboard data processing.

Methodology for Vehicle Trajectory Detection Using Long Distance Image Tracking (원거리 차량 추적 감지 방법)

  • Oh, Ju-Taek;Min, Joon-Young;Heo, Byung-Do
    • International Journal of Highway Engineering
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    • v.10 no.2
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    • pp.159-166
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    • 2008
  • Video image processing systems (VIPS) offer numerous benefits to transportation models and applications, due to their ability to monitor traffic in real time. VIPS based on a wide-area detection algorithm provide traffic parameters such as flow and velocity as well as occupancy and density. However, most current commercial VIPS utilize a tripwire detection algorithm that examines image intensity changes in the detection regions to indicate vehicle presence and passage, i.e., they do not identify individual vehicles as unique targets. If VIPS are developed to track individual vehicles and thus trace vehicle trajectories, many existing transportation models will benefit from more detailed information of individual vehicles. Furthermore, additional information obtained from the vehicle trajectories will improve incident detection by identifying lane change maneuvers and acceleration/deceleration patterns. However, unlike human vision, VIPS cameras have difficulty in recognizing vehicle movements over a detection zone longer than 100 meters. Over such a distance, the camera operators need to zoom in to recognize objects. As a result, vehicle tracking with a single camera is limited to detection zones under 100m. This paper develops a methodology capable of monitoring individual vehicle trajectories based on image processing. To improve traffic flow surveillance, a long distance tracking algorithm for use over 200m is developed with multi-closed circuit television (CCTV) cameras. The algorithm is capable of recognizing individual vehicle maneuvers and increasing the effectiveness of incident detection.

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The Current Quality Control and State of Scorched Particles in Infant formula in Korea (한국 조제분유의 초분 관리 실태 및 현황)

  • Jeon, Jeong-Wook;Juhn, Seok-Lak;Chun, Ho-Nam;Yun, Sung-Seob
    • Journal of Dairy Science and Biotechnology
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    • v.25 no.1
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    • pp.55-60
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    • 2007
  • Contents of scorched particles in infant formula were studied to provide a scientific evidence for standardization of Food Regulation in Korea. The specification of scorched particles in infant formula in Korea was satisfied with CODEX, USDA and so on. But food regulations for scorched particles in baby food are not mentioned in Korea. Nowadays social interests of scorched particles in infant formula are being increased in the respect of safety for baby food. The composition and contents of scorched particles were analyzed with Scanning Electron Microscope-Energy Dispersive X-ray Spectrometer(SEM-EDS) and Inductively Coupled Plasma Mass Spectrometer(ICP-MS). The results indicate that the scorched particles consist Ca, Na, Fe, Mg and trace elements derived from the ingredient of infant formula. Infant formula are composed of milk, skimmed milk, whey, mixed vegetable oils, minerals and vitamins. These results also show that the contents of scorched particles of infant formula in Korea are little or similar level to those reported in other countries. In general, heavy metals derived from scorched particle are originally used as a source of minerals in infant formula. And it has been thought that they doesn't effect on Provisional Tolerable Weekly Intake set by FAO/WHO for contents and composition of scorched particles.

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Validation of ICP-MS method for trace level analysis of Pb in plasma (혈장 중 극미량 납 분석을 위한 ICP-MS 분석법 검증)

  • Lee, Sung-Bae;Kim, Yong-Soon;Lee, Yong-Hoon;Ahn, Byung-Joon;Kim, Nam-Soo;Lee, Byung-Kook;Shin, Ho-Sang
    • Analytical Science and Technology
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    • v.28 no.5
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    • pp.309-316
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    • 2015
  • The analytical method of lead in plasma by ICP-MS was validated after securing environment within class 1,000 classification. We tested specificity and accuracy of within-run and between-run. According to measurement of the amount of suspended particulates in a clean room, 0.3~62 particles were detected in 0.3 µm size while 0.0~28.3 particles were observed in 0.5 µm size. Total suspended particulates met required environment with up to 90.3 particles. The MDL (Method detection limit) of the sample which has been fabricated using fetal bovine serum (FBS) blank was 1.77 ng/L, and LOQ (Limit of quantification) was 5.55 ng/L. The slope, intercept and correlation coefficient of the calibration curve were y=1.09×10−3x+4.88×10−2 and r=0.9999, which showed good correlation. The specificity, within-run and between-run accuracy satisfied the standard at more than 50 ng/L. The average lead concentration in plasma of the general people, current workers and retired workers was 55.4 ng/L, 440 ng/L, and 132 ng/L.

The Role of Archive as cultural memory in the age of Big Data (빅 데이터 시대 문화적 기억 보존소로서의 영상 아카이브의 역할)

  • Cho, Byung-Chul;Yuk, Hyun-Seung
    • Journal of Digital Convergence
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    • v.12 no.2
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    • pp.1-10
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    • 2014
  • Recently, the value and the status of the digital archives that are built individually in the crossroads of oblivion and memory are due to big data has attracted attention globally is confusing. Video data that contains the cultural memory of the digital archive, such as culture, art, life, society, and social conditions of the time, it is a cultural heritage of national common expressed. Also, it remains a trace of history from the various media just like magazines, books, painting, photography, and film. Digital archive system is one of the best research results of media convergence and it has also a good opportunity to take full advantage of the new opportunities and cultural assets. The collection of infinite information of big data in perspective transient that exist at the same time compatibility of big data, it is trying to dismantle the cultural memory of us. It was asserted that must meet the criteria which can correspond to via the new digital era, will be applied to preserve the traditional media. The current image archive is necessary to accommodate proper two different directions.