• Title/Summary/Keyword: VIS

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Some considerations for the analytical approaches to measure atmospheric ammonia: tests on a relative performance of a portable colorimeter against UV/VIS spectrophotometer (대기 중 암모니아 성분의 분석법 연구: UV/VIS 분광계를 이용한 간이비색계의 상대 성능평가)

  • Kim, K.H.;Park, S.Y.;Kim, S.T.
    • Analytical Science and Technology
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    • v.18 no.5
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    • pp.425-430
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    • 2005
  • In this study, we investigated the performance of a portable colorimeter used for the measurements of atmospheric ammonia against the more reliable method like UV/VIS spectrophotometer. For the purpose of this study, we tested a portable colorimeter and UV/VIS spectrophotometer for such basic analytical parameters as detectibility, reproducibility, linearity, and accuracy. According to our study, the performance of the colorimeter was fairly good to show a good agreement with the UV/VIS system. However, the performance of colorimeter suffered from both low and high concentration ranges: it was found to have very poor reproducibility at lower concentration (below $10\mu}g$), while its linear dynamic range was limited at the upper end (e.g., near $100{\mu}g$). If we assume that air samples are collected up to 30 liter, it implies that the colorimeter can be used to measure samples containing NH3 in the range of 500 ppb to 5 ppm (without the aid of diluting technique). Consequently, we recommend the use of such instrument with the awareness of its basic properties pertaining to the fundamental performance (such as its detectable range).

An Analysis on the R&D Productivity and Efficiency of Korea: Focused on Comparison with the OECD Countries (우리나라의 R&D 생산성 및 효율성 분석: OECD 국가와의 비교를 중심으로)

  • Kim, Young-H.;Kim, Sun-G.
    • Journal of Technology Innovation
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    • v.19 no.1
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    • pp.1-27
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    • 2011
  • This paper aims to measure and analyze R&D productivities and efficiencies of 17 major OECD countries including Korea over the 1984-2008 period by using the Malmquist Productivity Index and Data Envelopment Analysis, classifying R&D performance into an output and outcome aspects. It also searches the Korea's current status and characteristics in each R&D stage to enhance Total Factor Productivity (TFP) compared with other developed countries. Our major findings are the followings: (i) Korea's productivity index of R&D input vis-a-vis R&D output is very high (13.39% annual growth rate) compared with those of major advanced countries, whereas the annual average of efficiency index is very low (0.33), i.e. Korea's technical efficiency index has risen to 0.83 at the last time series started at 0.10 point and come up to the level of major advanced countries. (ii) the Korea's productivity index of R&D output vis-a-vis R&D outcome is very low (14.02% annual reduction rate) compared with those of major advanced countries, whereas the annual average of efficiency index is very high (0.22), i.e. Korea's integrated frontier technical efficiency index has dropped to 0.057 at the last time series started at 1.00 point and coming up to the level of major advanced countries. (iii) The productivity of R&D input vis-a-vis R&D outcome is positively correlated with that of R&D output vis-a-vis R&D outcome and the growth of R&D input factors. In a nutshell, it implicates that the effort to take advantage of R&D outputs, namely establishing the diffusion and commercialization system of technical knowledge to the level of developed countries, should be strengthened over that on the growth of R&D investment and output for enhancing R&D productivity and efficiency in Korea.

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Path Analysis of Geometric Psychology type, Positive Psychological Capital, and Communication Competence for University Students (대학생의 도형심리 유형, 긍정심리자본, 의사소통능력 간의 경로분석)

  • Kim, Myoung-Sook;SEO, Ho-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.355-364
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    • 2018
  • The objective of this study is to conduct basic research for the development of programs for improving university students' communication competence. As such, it seeks to determine if positive psychological capital can mediate the relationship between the geometric psychology type and communication competence. To that end, 321 Korean university students were surveyed using a questionnaire, and the data underwent scale reliability analysis, regression analysis, and path analysis. Regression analysis revealed the consistent regression results of variables, including geometric psychology type, positive psychological capital, and communication competence. Path analysis confirmed that positive psychological capital mediated the relationship between the geometric psychology type and communication competence, and the results suggested different patterns according to type of geometric psychology. The circle type mediated the sub-variable resilience vis-a-vis communication competence, and directly influenced the latter. The triangle type mediated the sub-factors of positive psychological capital - self-efficacy and resilience -vis-a-vis communication competence, and thus influencing the latter. The square type mediated the sub-factor of positive psychological capital - self-efficacy - vis-a-vis communication competence, and directly influenced the latter. The S type did not mediate positive psychological capital vis-a-vis communication competence, but directly influenced the latter. Thus, considering the above findings, in order to develop university students communication improvement programs, programs should be developed with the application of positive psychological capital considering geometric psychology type.

The Study on the Role of 3D Animated Pre-visualization in VFX FilmProduction (VFX 영화 제작을 위한 3D animatied Pre-visualization(3D애니메이티드 사전시각화)의 역할에 관한 연구)

  • Park, Sung-Ho
    • Cartoon and Animation Studies
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    • s.51
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    • pp.293-319
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    • 2018
  • Thanks to the advancement of the related technologies and equipment, today's video contents like movies, animations and soap operas are rapidly expanding their expressible cinematic imagination area. In order to fulfill the elevated visual expectations of audiences and realize exciting storytelling and fantastic world, the fusion of different techniques is actively used, and the reality for visual effects and image synthesis is increasing more and more. Accordingly, recent VFX-oriented movies using CG have a much more complicated production process than before. Therefore, the importance of Pre-visualization, aka Pre-vis is becoming bigger in the planning process for sophisticated design. Pre-vis means that the advance visualization for stories or directing ideas in the planning process before starting production of movies or animations. 3D animated Pre-visualization realizing directors' abstract and ambiguous ideas in 3 dimensional environment in advance is, as a powerful means for visual storytelling, briskly used focusing on the VFX film industry on which the present CG is broadly used, and the role of Pre-vis throughout productions has increased compared to the past. The studies, however, on the role and utility of Pre-vis are not enough. Therefore, this study was conducted on the role of Pre-vis used for present VFX movie productions using the examples of 3D animated Pre-visualization production in which the researcher of this study participated. In this study, the role of the Pre-vis that is subdivided presently, is divided into and 3D animatics and their each role is analyzed with the example images. Through this, the characteristics that Pre-vis should have are clarified and the concept of the advantages and utility led by the use of Pre-vis in productions is strengthened. The goal of this study is to induce active uses of Pre-vis throughout productions after forming consensus about the various roles of Pre-vis and their utility.

Development of Nondestructive Sorting Method for Brown Bloody Eggs Using VIS/NIR Spectroscopy (가시광 및 근적외선 전투과 스펙트럼을 이용한 갈색 혈란 비파괴선별 방법 개발)

  • Lee, Hong-Seock;Kim, Dae-Yong;Kandpal, Lalit Mohan;Lee, Sang-Dae;Mo, Changyeun;Hong, Soon-Jung;Cho, Byoung-Kwan
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.1
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    • pp.31-37
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    • 2014
  • The aim of this study was the non-destructive evaluation of bloody eggs using VIS/NIR spectroscopy. The bloody egg samples used to develop the sorting mode were produced by injecting chicken blood into the edges of egg yolks. Blood amounts of 0.1, 0.7, 0.04, and 0.01 mL were used for the bloody egg samples. The wavelength range for the VIS/NIR spectroscopy was 471 to 1154 nm, and the spectral resolution was 1.5nm. For the measurement system, the position of the light source was set to $30^{\circ}$, and the distance between the light source and samples was set to 100 mm. The minimum exposure time of the light source was set to 30 ms to ensure the fast sorting of bloody eggs and prevent heating damage of the egg samples. Partial least squares-discriminant analysis (PLS-DA) was used for the spectral data obtained from VIS/NIR spectroscopy. The classification accuracies of the sorting models developed with blood samples of 0.1, 0.07, 0.04, and 0.01 mL were 97.9%, 98.9%, 94.8%, and 86.45%, respectively. In this study, a novel nondestructive sorting technique was developed to detect bloody brown eggs using spectral data obtained from VIS/NIR spectroscopy.

Measurements of Defects after Machining CFRP Holes Using High Speed Line Scan (고속 라인 스캔 방식을 이용한 CFRP 가공 홀 표면 및 내부 결함 검사)

  • Kim, Teaggyum;Kyung, Daesu;Son, Unchul;Park, Sun-Young
    • Journal of the Korean Society for Precision Engineering
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    • v.33 no.6
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    • pp.459-467
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    • 2016
  • Using a line scan camera and a Galvano mirror, we constructed a high-speed line-scanning microscope that can generate 2D images ($8000{\times}8000pixels$) without any moving parts. The line scanner consists of a Galvano mirror and a cylindrical lens, which creates a line focus that sweeps over the sample. The measured resolutions in the x (perpendicular to line focus) and y (parallel to line focus) directions are both $2{\mu}m$, with a 2X scan lens and a 3X relay lens. This optical system is useful for measuring defects, such as spalling, chipping, delamination, etc., on the surface of carbon fiber reinforced plastic (CFRP) holes after machining in conjunction with adjustments in the angle of LED lighting. Defects on the inner wall of holes are measured by line confocal laser scanning. This confocal method will be useful for analyzing defects after CFRP machining and for fast 3D image reconstruction.

Spectroscopic Studies on the Oxidation of Catechin in Aqueous Solution

  • Bark, Ki-Min;Yeom, Ji-Eun;Yang, Jeong-Im;Yang, Ik-Jun;Park, Chul-Ho;Park, Hyoung-Ryun
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3443-3447
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    • 2011
  • The spectroscopic behavior of catechin (5,7,3',4'-tetrahydroxyflavan-3-ol), has been studied in the presence and the absence of air using UV-vis absorption spectrophotometry and fluorescence spectroscopy. The UV-vis absorption spectrum of catechin shows a very sharp and strong absorption maximum peak at 275 nm in deaerated water. New absorption maximum peaks appeared in aerated water, as well as in basic aqueous solution, caused by the oxidation of catechin. The absorbances in the UV-vis absorption spectrum of catechin decreased when the solution was left in the dark for a long time. The fluorescence emission spectrum of catechin after a long time period differs markedly from that in freshly prepared solution; the fluorescence maxia shifted as time passes after adding catechin to the solutions. When the deaerated basic catechin solutions were left in the dark for a long time, their fluorescence quantum yields were found to be nearly zero. This suggests that the oxidized catechin molecules were seen to have slowly undergone successive chemical reactions in basic buffer solution.

Development of Nondestructive Grouping System for Soil Organic Matter Using VIS and NIR Spectral Reflectance

  • Sung J.H.
    • Agricultural and Biosystems Engineering
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    • v.6 no.1
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    • pp.15-21
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    • 2005
  • This study was conducted to develop a nondestructive grouping system for soil organic matter using visible (VIS) and near infrared (NIR) spectroscopic method. The artificial light was irradiated on the cut soil surface at 15 to 20 cm depths to reduce the errors of light at open field. The reflectance energy from the cut soil surface was measured to group the soil organic matter using VIS/NIR light sensor with narrow band pass filter. From reflectance spectra of soil samples, the sensitive wavelengths for measuring the soil organic matter were selected and compared to previous research results. The grouping system for soil organic matter consisted of light sensor with band pass filter measuring the reflectance energy of the cut soil surface, global positing system (GPS), analog-to-digital (AD) converter, computer and operating software. The regression models to predict the soil organic matter were developed and evaluated. From field test, the accuracies of the developed light sensor system were 81.3% for five-stage grouping of the soil organic matters and 91.0% for three-stages grouping of the soil organic matters, respectively. It could be possible to support the decision making for variable rate applications with the developed grouping system for soil organic matter in precision agriculture.

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Ultraviolet Blocking Material Based on Silver-doped Hydroxyapatite (수산화인회석에 은이 도입된 자외선차단재료)

  • Pyo, Eunji;Kim, Youngyong;Kwon, Ki-Young
    • Applied Chemistry for Engineering
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    • v.27 no.6
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    • pp.669-671
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    • 2016
  • Hydroxyapatite (HAP) was prepared by a hydrothermal synthesis method and also silver was introduced on the surface of HAP through an ion exchange reaction. The crystal phase and morphology of HAP were then evaluated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). In addition, the absorption property of HAP was characterized by diffuse reflectance UV-Vis spectroscopy. The presence of silver nanoparticles on the surface of HAP was also verified by XRD and TEM analysis. Particularly, the silver doped HAP showed an enhanced absorption property in UV-Vis region compared to that of the pristine HAP.

Electrochemical Behaviors of Copper-1-(2-pyridylazo)-2-naphthol Complex in Acetonitrile (아세토니트릴 용매 중에서 Copper-1-(2-pyridylazo)-2-naphthol 착물의 전기화학적 성질)

  • Zun-Ung Bae;Sang-O Oh;Hee-Bong Song;Tae-Myung Park
    • Journal of the Korean Chemical Society
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    • v.37 no.10
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    • pp.888-894
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    • 1993
  • The electrochemical behaviors of copper-1-(2-pyridylazo)-2-naphthol(Cu-PAN) complex in acetonitrile (AN) solution have been investigated by the use of cyclic voltammetry, DC-polarography, controlled potential coulometry and UV-Vis spectroscopy. Cu-PAN complex in acetonitrile exhibit three reduction waves at -1.27 V, -1.64 V and -2.08 V vs. Ag/AgNO$_3$(AN). The numbers of electron involved in each reduction step was calculated with controlled potential coulometry, and reduction product was identified with UV-Vis spectrum. As the result, we proposed the reduction mechanism of the Cu-PAN complex in acetonitrile.

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