• Title/Summary/Keyword: Sources of variation

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Thin Film Vacuum Process Technology via Chemical Vapor Deposition Methods (화학기상증착법(CVD)을 이용한 진공 박막 공정기술)

  • Hong, Wan-Shick
    • Vacuum Magazine
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    • v.1 no.3
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    • pp.9-13
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    • 2014
  • Vacuum growth of thin films via chemical vapor deposition (CVD) methods has been extensively used in modern semiconductor and flat panel display industries. The CVD processes have a wide range of variation and are categorized according to their working conditions, power sources, precursor materials, and so forth. Basic components and process steps common to all CVD branches are discussed. In addition, characteristics and applications of two major CVD techniques - LPCVD and PECVD - are reviewed briefly.

Chemical Properties of Sediment in Nanakita Estuarine Tidal Flat: Estimation of Sedimentary Organic Matter Origin by Stable Isotope and Fatty Acid

  • Shin, Woo-Seok;Aikawa, Yoshio;Nishimura, Osamu
    • Environmental Engineering Research
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    • v.17 no.2
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    • pp.77-82
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    • 2012
  • The spatial variation of organic matter sources in tidal flat sediment of the Nanakita River estuary, involving Gamo lagoon on the north-east coast of Honshu Island, Japan, was examined using carbon stable isotopes and fatty acid biomarkers. The spatial variation of total organic carbon (TOC) contents and ${\delta}^{13}C$ values were highly variable in between the stations, such as sandy flat (1.3 mg/g, -21.0‰), sand-muddy flat (2.6 mg/g, -21.9‰), and muddy flat (24.9 mg/g, -25.9‰), respectively. Particularly, at the muddy flat, high TOC content and low ${\delta}^{13}C$ value of the sediments indicated that the surface sediment was composed largely of terrestrial organic matter. Whereas, at the sandy flat and sand-muddy flat, the high ratios of diatom and bacteria biomarkers indicated the high contribution of abundant microorganism along with marine organic matter in sediment composition. From these results, it considered that the amount and origin of transported sedimentary organic matter indicated different characteristics in this study stations.

Gage R&R Study on Abdominal Sonography for Measuring Distance from Sangwan (CV13) to Pancreas - A Pilot Study - (복부초음파를 이용한 상완혈(上脘穴)-췌장 수직거리 측정시스템의 재현성 반복성 평가실험-A Pilot Study-)

  • Nam, Dong-Hyun
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.14 no.2
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    • pp.75-84
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    • 2010
  • Objectives: The objective of the current study is to determine whether an ultrasound device system is adequate for measuring distance from Sangwan (CV13) to pancreas. Methods: We recruited 3 healthy young male subjects and 2 sonographers. The each sonographer measured vertical shortest distance from CV13 to pancreas with a ultrasound device three times in random order. Because the total variation could be divided into repeatability, reproducibility and subject-to-subject variation in Gage R&R method, we compared the sources of variation associated with the measurement system with an analysis of variance model. Results & Conclusions: Number of distinct categories is calculated on the basis of standard deviation of subject-to-subject divided by standard deviation of total Gage R&R. If the number of categories is five or more, the measurement system may be acceptable for the analysis of the process. The number of distinct categories of the ultrasound device system for measuring distance from CV13 to pancreas was 6.29. So we concluded that repeatability and reproducibility of the ultrasound device system for measuring distance from CV13 to pancreas was acceptable.

The Effects of Cigarette Component Variability on Filter Ventilation Variability by Monte Carlo Analysis. (재료품 품질의 변동이 필터 공기희석율 변동에 미치는 영향)

  • 김정열;김종열;신창호;정한주
    • Journal of the Korean Society of Tobacco Science
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    • v.22 no.2
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    • pp.151-156
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    • 2000
  • The variability of a ventilated filter cigarette depends on the details of its construction and on the variabilities of its components. Variations in filter ventilation arise from many sources, including variations in tobacco rod pressure drop, filter tip pressure drop, tipping paper permeability, and plugwrap permeability. To reduce the filter ventilation variability, the variability of filter ventilation levels in ventilated cigarettes is studied by Monte Carlo Analysis. For each trials a value is selected for tobacco rod pressure drop, filter tip pressure drop, tipping paper permeability, and plugwrap permeability. These values are selected randomly from a normal distribution based on the target and coefficient of variation for each input variable. The results of this analysis for filter ventilation variation suggest that the variations of filter ventilation are dependent on the details of cigarette designs studied and reducing the variability of any cigarette component will reduce filter ventilation variability. For typical cigarettes, variation in the permeability of tipping paper is usually the most significant contributor to filter ventilation variability. Results of a Monte Carlo Analysis could provide both general insights and specific practical guidance about the design of ventilated filter cigarettes.

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A New Battery Approach to Wind Generation System in Frequency Control Market

  • Nguyen, Minh Y.;Nguyen, Dinh Hung;Yoon, Yong Tae
    • Journal of Electrical Engineering and Technology
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    • v.8 no.4
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    • pp.667-674
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    • 2013
  • Wind power producers face many regulation costs in deregulated environment, which remarkably lowers the value of wind power in comparison with conventional sources. One of these costs is associated with the real-time variation of power output and being paid in frequency control market according to the variation band. This paper presents a new approach to coordination of battery energy storage in wind generation system for reducing the payment in frequency control market. The approach depends on the statistic data of wind generation and the prediction of frequency control market price to determine the optimal variation band which is then kept by the real-time charging and discharging of batteries, ultimately the minimum cost of frequency regulation can be obtained. The optimization problem is formulated as trade-off between the decrease in the regulation payment and the increase in the cost of using battery, and vice versus. The approach is applied to a study case and the results of simulation show its effectiveness.

A Study on the Syntagma & Paradigm by Repetition, Variation and Contrast in Ads

  • Choi, Seong-hoon
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.7 no.9
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    • pp.1-12
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    • 2017
  • This study is the academic work to explore the potential meanings of print advertisements. Linguistic features such as repetition, variation, contrast and phonological structure in the verbal texts of ads can give rise to shades-of-meaning or slight variations in advertising. The language of advertising is not only language in words. It is also a language in images, colors, and pictures. Pictures and words combine to form the advertisement's visual text.. While the words are very important in delivering the sales message, the visual text cannot be ignored in advertisements. Forming part of the visual text is the paralanguage of the ad. Paralanguage is the meaningful behaviour accompanying language, such as voice quality, gestures, facial expressions and touch in speech, and choice of typeface and letter sizes in writing. Foregrounding is the throwing into relief of the linguistic sign against the background of the norms of ordinary language. This paper focuses its discussion on the advertisements within the framework of the paradigmatic and the syntagmatic relationship. The sources of ads have been confined to Malboro. The ads were reselected based on purposive sampling methods.

On the Prediction and Variation of Air Pollutants Concentration in Relation to the Meteorological Condition in Pusan Area (기상조건에 따른 부산지역 대기오염물질 농도변화와 예측에 관한 연구)

  • 정영진;이동인
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.3
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    • pp.177-190
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    • 1998
  • The concentrations of air pollutants In large cities such as Pusan area have been increased every year due to the increasing of fuels consumption at factories and by vehicles as well as the gravitation of the population. In addition to the pollution sources, time and spatial variation of air pollutants concentration and meteorological factors have a great influence on the air pollution problem. Especially , its concentration is governed by wind direction, wind speed, precipitation, solar radiation, temperature, humidity and cloud amounts, etc. In this study, we have analyzed various data of meteorological factors using typical patterns of the air pressure to investigate how the concentration of air pollutants is varied with meteorological condition. Using the relationship between meteorological factors (air temperature, relative humidity, wind speed and solar radiation) and the concentration of air pollutants (SO2, O3) , experimental prediction formulas for their concentration were obtained. Therefore, these prediction formulas at each meteorological factor in a pressure pattern may be roughly used to predict the air pollutants concentration and contributed to estimate the variation of its value according to the weather condition in Pusan city.

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TEMPORAL VARIATION OF HCO+ 1-0 GALACTIC ABSORPTION LINES TOWARD NRAO 150 AND BL LAC

  • Han, Junghwan;Yun, Youngjoo;Park, Yong-Sun
    • Journal of The Korean Astronomical Society
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    • v.50 no.6
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    • pp.185-190
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    • 2017
  • We present observations of $HCO^+$ 1-0 absorption lines toward two extragalactic compact radio sources, NRAO 150 and BL Lac with the Korean VLBI Network in order to investigate their time variation over 20 years by Galactic foreground clouds. It is found that the line shape of $-17kms^{-1}$ component changed marginally during 1993-1998 period and has remained unaltered thereafter for NRAO 150. Its behavior is different from that of $H_2CO$ $1_{10}-1_{11}$, suggesting chemical differentiation on ~ 20 AU scale, the smallest ever seen. On the other hand, BL Lac exhibits little temporal variation for the $HCO^+$ and $H_2CO$ lines. Our observation also suggests that Korea VLBI Network performs reliably in the spectrum mode in that the shapes of the new $HCO^+$ 1-0 spectra are in good agreement with the previous ones to an accuracy of a few percent except the time varying component toward NRAO 150.

A Study on Cyclic Variation by Idling in Gasoline Vehicle (가솔린자동차의 무부하 운전에서 사이클변동에 관한 연구)

  • Han, Sung-Bin;Kim, Sung-Mo
    • Journal of Energy Engineering
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    • v.18 no.3
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    • pp.156-162
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    • 2009
  • Cylinder-pressure based combustion analysis provides a mechanism through which a combustion researcher can understand the combustion process. This paper was to identify the most significant sources of cycle-to-cycle combustion variability in a spark ignition engine at idle. To analyse the cyclic variation in the test engine, the burn parameters are determined on a cycle-to-cycle basis through analysis of the engine pressure data. The burn rate analysis program was used in the analysis of the data. Burn parameters were used to determine the variations in the input parameter-i.e., fuel, air, residual mass, and so on.

Monthly Variation of n-alkanes concentration in PM2.5 of the Anmyeon Island (안면도 대기 중 PM2.5 내 n-alkanes의 월별 농도 분포 특성)

  • Kim, Ki Ae;Lee, Jong Sik;Kim, Eun Sil;Jung, Chang Hoon;Kim, Yong Pyo;Lee, Ji Yi
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.1
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    • pp.166-176
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    • 2018
  • The n-alkanes which are stable compounds in the atmosphere are emitted by anthropogenic sources and biological sources. The goal of this study is to understand characteristics of n-alkane distributions in $PM_{2.5}$ of the Anmyeon Island which is one of background site in Korea. The concentration of n-alkanes in $PM_{2.5}$ was measured at Anmyeon Island for one year from June 2015 to May 2016. The average concentration of total n-alkanes (${\sum}$ n-alkanes) from C20 to C34 was $14.02{\pm}10.26ng\;m^{-3}$ and ranged from 1.77 to $47.65ng\;m^{-3}$. Various diagnostic parameters were used to identify the source. As a result, it is considered that Anmyeon Island had a large influence of biological sources during non-heating period, while the influence of anthropogenic emission during the heating period was significant. Principle Component Analysis (PCA) was performed and yielded three components that accounted for 93.6% of the total variance in n-alkanes. Factor 1, which accounted for 42.3% of the total variance, indicated anthropogenic source including fossil fuel and biomass combustion, while, Factor 3 was interpreted as the biological sources such as plant wax.