• Title/Summary/Keyword: media-source

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Spatial moment analysis of multispecies contaminant transport in porous media

  • Natarajan, N.;Kumar, G. Suresh
    • Environmental Engineering Research
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    • v.23 no.1
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    • pp.76-83
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    • 2018
  • Spatial moment analysis has been performed on the concentration of the first species in a multispecies solute transport in porous media. Finite difference numerical technique was used in obtaining the solute concentration. A constant continuous source of contaminant was injected at the inlet of the domain. Results suggest that the decaying of solute mass increases as the magnitude of mean fluid velocity increases. The dispersion coefficient is highly time dependent under decaying of solutes with a complex behavior of mixing of solutes. The solute mobility and mixing varies non-linearly with time during its initial period, while the same ceases with higher decay rates of the first species much faster.

Construction of Scientific Impact Evaluation Model Based on Altmetrics

  • Li, Jiapei;Shin, Seong Yoon;Lee, Hyun Chang
    • Journal of information and communication convergence engineering
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    • v.15 no.3
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    • pp.165-169
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    • 2017
  • Altmetrics is an emergent research area whereby social media is applied as a source of metrics to evaluate scientific impact. Recently, the interest in altmetrics has been growing. Traditional scientific impact evaluation indictors are based on the number of publications, citation counts and peer reviews of a researcher. As research publications were increasingly placed online, usage metrics as well as webometrics appeared. This paper explores the potential benefits of altmetrics and the deep relationship between each metrics. Firstly, we found a weak-to-medium correlation among the 11 altmetrics and visualized such correlation. Secondly, we conducted principal component analysis and exploratory factor analysis on altmetrics of social media, divided the 11 altmetrics into four feature sets, confirming the dispersion and relative concentration of altmetrics groups and developed the altmetrics evaluation model. We can use this model to evaluate the scientific impact of articles on social media.

Penetration depth and Wave Propagation in Random Media (무질서한 매질에서 침투깊이와 파동 전파)

  • Kim, Ki-Jun;Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.23 no.1
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    • pp.70-76
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    • 2006
  • The influence of fluorophor, scatterer, absorber in turbid materials by light scattering were interpreted for the scattered fluorescence intensity and wavelength, it is studied the molecular property by laser induced fluorescence spectroscopy. It can be found that the effects of optical property are penentrated in scattering media by the optical $parameters({\mu}s$, ${\mu}a$, ${\mu}t$, ${\gamma}$, ${\rho})$. The value of scattering coefficient ${\mu}s$ is large appeared by means of the increasing particles of scattering, it can be found that the slope appears exponentially as a function of distance from laser source to detector. It may also utilize in designing the best model for oil chemistry, laser medicine and application of medical engineering.

Quantifying Influence in Social Networks and News Media

  • Yun, Hong-Won
    • Journal of information and communication convergence engineering
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    • v.10 no.2
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    • pp.135-140
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    • 2012
  • Massive numbers of users of social networks share various types of information such as opinions, news, and ideas in real time. As a new form of social network, Twitter is a particularly useful information source. Studying influence can help us better understand the role of social networks. The popularity of social networks like Twitter is primarily measured by the number of followers. The number of followers in Twitter and the number of users exposed to news media are important factors in measuring influence. We chose Twitter and the New York Times as representative media to analyze the influence and present an empirical analysis of these datasets. When the correlation between the number of followers in Twitter and the number of users exposed to the New York Times is computed, the result is moderately high. The correlation between the number of users exposed to the New York Times and the number of sections including the users on it, was found to be very high. We measure the normalized influence score using our proposed expression based on the two correlation coefficients.

Effects of Dietary Fructan on Cecal Enzyme Activities in Rats

  • Kang, Soon-Ah;Chun, Uck-Han;Jang, Ki-Hyo
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.6
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    • pp.582-586
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    • 2005
  • In this Study, we have attempted to determine the effects of dietary fructose polymers (fructan), high molecular-weight ${\beta}-(2,6)-linked$ levan, and low-molecular-weight ${\beta}-(2,1)-linked$ inulin, on two intestinal enzymes $({\beta}-glucuronidase\;and\;{\beta}-glucosidase)$. As a preliminary experiment, when intestinal microflora were cultured in anaerobic media harboring levan or its oligosaccharides, bacterial cell growth was observed in the levanoligosaccharide-supplemented media, but not in the levan-supplemented media, indicating that levan's size is important for the utilization by intestinal bacteria of levan as an energy Source. In our animal study, the intake of a levan-rich diet was determined to significantly attenuate the activity of the harmful enzyme $({\beta}-glucuronidase$, but d id not affect the activity of ${\beta}-glucosidase$.

Multimedia Synchronization Scenario Method for Synchronization Anomaly (동기이상을 위한 멀티미디어 동기시나리오방법)

  • 전병호;김태균
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.31A no.9
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    • pp.44-52
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    • 1994
  • When a constructed multimedia application system transfers a various media of which quality of service is different, a previously constituted synchronization at source site generates the synchronization anomaly that the synchronization relation is broken by a delay or a data loss at destination. To solve the synchronization anomaly, we propose the “Multimedia synchronization scenario method : MSSM” which defines as one(1) event all objects generated at multimedia application and creates the optimal scenario of multimedia presentation under temporal constraints. The characteristics of MSSM can minimize the delay effect, guarantee the media stream continuity for preventing the media stretch, and provide the synchronization information to a user and/or a system. After deciding a synchronization possibility. MSSM confirm user its information. If there is a synchronization possibility. MSSM products optimal multimedia presentation scenario, and can present multimedia adaptively.

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A Study on the Synthesis of TE and TM Scattering Patterns of One-Dimensional Inhomogeneous Dielectric Media (일차원 비균질 유전매질의 TE 및 TM 산란패턴 합성에 관한 연구)

  • Nam, June-Seok;Jun, Sang-Jae;Jeon, Hoo-Dong;Jung, Jun-Sik;Park, Eui-Joon
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2003.11a
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    • pp.69-73
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    • 2003
  • In this paper, a synthesis method for the desired scattering pattern is presented when illuminating by TE-polarized and TM-polarized plane waves to arbitrary dielectric material. It is considered that the one-dimensional dielectric media are inhomogeneously distributed with continuously varying dielectric constants. Accordingly the desired patterns and the corresponding source distributions are inversely transformed by the proposed algorithm which are based on the one-dimensional inverse scattering problem. Some bandstop spatial filter are illustrated for applications.

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버섯 배지를 이용한 tyrosinase 저해제 발효

  • Jung, Sung-Won;Han, Dae-Seok;Kim, Seok-Joong;Chun, Moon-Jin
    • Microbiology and Biotechnology Letters
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    • v.24 no.2
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    • pp.227-233
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    • 1996
  • Tyrosinase is an enzyme which catalyzes an enzymatic browning of some foods and in vivo synthesis of melanin. In order to produce natural and edible inhibitor of the enzyme which is expected to have whitening effect on melanogenesis, a microorganism was selected from fermented foods. It was named as NU-7, and cultured in mushroom (Lentinus edodes, Shiitake) media. Optimal media to produce tyrosinase inhibitor was formulated by varing nitrogen or carbon content. If glucose content was in a range of 3-20% and ammonium sulfate was in a range of 0-0.25%, production of inhibitor was independent of cell mass. Addition of ammonium sulfate as a nitrogen source had little effect on inhibitor production. Production of inhibitor (Y) was proportionally related to shiitake content (X) with a regression equation of Y= -0.96X$^{2}$ + 13.07X + 14.43 (R = 0.96). These results indicate that shiitake and glucose are necessary for the production of tyrosinase inhibitor. In the analysis of mycotoxin in culture broth, aflatoxin was not detected, suggesting that it would be probably edible.

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A Study on the windowing structure DMB contents (DMB전용콘텐츠의 창구화에 관한 연구)

  • Yoon, Hong Keun
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.4 no.1
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    • pp.89-104
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    • 2008
  • The aim of this study is to analyze the distribution structure of exclusive digital muti-media broadcasting's contents. This study takes into distribution wether exclusive contents create an additional window being serviced to other media. And it investigates how the contents work in window through analysis of programming table and interview with programming editors of each DMB service company. The window effect is a same notion to the one source multi use. In the film industry, window means a movie distribution that a film can be on one after the other starting the cinema, DVD, local cable channel, and terrestrial television. The key point of this paper is how to new media, DMB, creates its additional window and changes the existing window structure.

A study on Alkalophilic Bacteria Producing $\beta$-Galactosidase. -Isolations and Cultural Characteristics (I)- ($\beta$-Galactosidase를 생산하는 호알카리성 세균에 관한 연구 -균주의 분리 및 배양조건 (I)-)

  • Yun, Seong-Sik;Min, Do-Sik;Yu, Ju-Hyeon
    • The Korean Journal of Food And Nutrition
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    • v.1 no.2
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    • pp.68-75
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    • 1988
  • A strain of alkalophilic Bacillus sp. YS-309 has been isolated from domestic soil. It belongs to genus Bacillus from its morphological and biochemical characteristics. The strain grows better in the alkaline media rather than in the neutral media. The optimum pH and temperature for growth were observed at 8.5 and 4$0^{\circ}C$, respectively. Glucose, lactose and maltose were appeared as good carbon source but soluble starch and fructose were utilized uneffectively for growth. Concentrations of lactose had affected both the cellular growth and the enzyme productions. The maximum growth and the highest enzyme productions were obtained at 0.5%(w/e) of lactose added in the media. B-Galactosidase from Bacillus sp. YS-309 was produced inducibly into the cell and total enzyme activities per ml were gradually decreased when the concentration of glucose increased.

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