• 제목/요약/키워드: Dispersion behavior

검색결과 491건 처리시간 0.027초

Herding Behavior in Emerging and Frontier Stock Markets During Pandemic Influenza Panics

  • LUU, Quang Thu;LUONG, Hien Thi Thu
    • The Journal of Asian Finance, Economics and Business
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    • 제7권9호
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    • pp.147-158
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    • 2020
  • We apply Return Dispersion Model by calculating CSAD (Cross-sectional standard deviation of return) and State Space Model to identify herding behavior in the period of pandemic (H1N1 and COVID-19). Employing data from TEJ and Data Stream, this paper examines whether the herding behavior is existing in Vietnam and Taiwan stock market, especially during pandemic influenza. We compare the differences in herding behavior between frontier and emerging markets by examining different industries across Vietnam and Taiwan stock market approaches. The results indicate solid evidence for investor herd configuration in the various industries of Vietnam and Taiwan. The herding impact in the industries will be greater than with the aggregate market. The different industries respond differently to influenza pandemic panics through uptrend and downtrend demonstrations. Up to 12 industries were found to have herding in Vietnam, while Taiwan had only 5 of 17 industries classified. Taiwan market, an emerging and herding-level market, has changed due to the impact of changing conditions such as epidemics, but not as strongly as in Vietnam. From there, we see that the disease is a factor that, not only creates anxiety from a health perspective, but also causes psychological instability for investors when investing in the market.

하천 감조부에 있어서 염분의 장기변동에 관한 연구 (Study on the long-term change of Chlorides in the tidal area of river)

  • 김원규
    • 한국환경과학회지
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    • 제3권1호
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    • pp.11-16
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    • 1994
  • Generally, it is difficult to predict water quality in a tidal river, because tidal flows make the transport phenomena more complicated. The purpose of this study is to clarify long-term mass transport in a tidal river through suggestion of simulation model. A simulation model based on a Lagrangian coordinate system, which has the advantage reducing numerical dispersion, was used to calculate changes in concentration of chlorides. Several field surveys were conducted to verify calculated results. Concludingly, long-term behavior of mas transport in a tidal river can be represented using the model.

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Experimental Research of Dispersion-behavior on Heavy Gases Regarding the Influence of Roughness and Slope of Ground in a Wind Tunnel

  • Kim, Jeong-Hun;Sylvius Hartwig
    • 한국산업안전학회:학술대회논문집
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    • 한국안전학회 2003년도 춘계 학술논문발표회 논문집
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    • pp.185-190
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    • 2003
  • 산업체 등에서 사용되고 있는 가스들중에서 일반적인 가스들과는 달리 위험한 가스(heavy gas)들은 누출사고시에 이들 고유한 확산과 계층화(stratification)방식에 의해 높은 위험성을 유발시키고 있다. 이러한 가스의 누출확산사고들과 일반적인 가스누출사고들의 비교는 그 사실들을 증명해주고 있다. 이런 사실에 의해 위험한 가스확산에 대한 실험과 고유특성을 고려한 확산모델의 개발이 여러 관점에서 진행되고 있으며, 이들의 중요성은 이미 세계적으로 의미를 부여하고 있다.(중략)

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자기충전용 ECC를 개발하기 위한 레올로지 특성에 관한 실험 (Rheological control to develop a self-consolidating ECC)

  • 김정수;이정한;김윤용;김진근
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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    • pp.539-540
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    • 2009
  • 이 연구에서는 레올로지 제어를 이용하여 자기충전용 ECC(Engineered Cementitious Composite)를 개발하는데 그 목적을 두었으며, 레올로지 제어를 위하여 시멘트 페이스트에 대한 시멘트와 혼화제(감수제, 증점제)의 흡착정도를 평가하였고, 모르타르에 대하여 자기충전성과 유동특성을 평가하였다.

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유리직물/에폭시 복합재료 보의 내부구조와 충격굽힘진동특성 (Microstructure and Impactive Flexural Vibration Characteristics of Glass-Fabric/Epoxy Composite Beams)

  • 서지웅;최낙삼
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 1999년도 춘계학술발표대회 논문집
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    • pp.53.1-56
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    • 1999
  • The vibration behavior of glass-fabric reinforced plastic(GFRP) composite beams subjected to various transverse impacts has been investigated as a function of fiber orientation and void fraction. Theoretical results of resonant frequency damping coefficient and modal amplitude dispersion using the Euler-beam theory were obtained along with the finite element analysis which were compared with experimental ones Consequently it was shown that the transverse vibration characteristics were largely affected by fiber orientation and void fraction.

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FDTD Simulation of Photonic-Crystal Lasers and Their Relaxation Oscillation

  • Song, G. Hugh;Kim, Soan;Hwang, Kyung-Hwan
    • Journal of the Optical Society of Korea
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    • 제6권3호
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    • pp.87-95
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    • 2002
  • We have developed an finite-difference time-domain program that can analyze photonic devices with gain and/or dispersion. As an example, a two-dimensional photonic-crystal laser is simulated. The simulation can show the relaxation oscillation behavior at extremely high current injection.

NMR Tools to Decipher Dynamic Structure of RNA

  • Lee, Janghyun;Choi, Byong-Seok
    • 한국자기공명학회논문지
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    • 제21권2호
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    • pp.55-62
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    • 2017
  • It is now well established that RNAs exhibit fundamental roles in regulating cellular processes. Many of these RNAs do not exist in a single conformation. Rather, they undergo dynamic transitions among many different conformations to mediate critical interactions with other biomolecules such as proteins, RNAs, DNAs, or small molecules. Here, we briefly review NMR techniques that describe the dynamic behavior of RNA by determining structural, kinetic, and thermodynamic properties.

Phase Behavior of Poly(ethylene-co-norbornene) in $C_6$ Hydrocarbon Solvents: Effect of Polymer Concentration and Solvent Structure

  • Kwon, Hyuk-Sung;Lee, Sang-Ho
    • Macromolecular Research
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    • 제11권4호
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    • pp.231-235
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    • 2003
  • Phase behavior information is necessary for accomplishing homogeneous copolymerization to obtain high yield of copolymers and prevent a fouling problem. Cloud-point data to $160^{\circ}C$ and 1,450 bar are presented for five $C_6$ hydrocarbon solvents, normal hexane, 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane, with poly(ethylene-co-53 mol% norbornene) ($PEN_{53}$). The pressure-concentration isotherms measured for $PEN_{53}$/n-hexane have maximums that range between 5 and 12 wt% $PEN_{53}$. The cloud-point curves for $PEN_{53}$ all have negative slopes that decrease in pressure with temperatures. The single-phase region of $PEN_{53}$ in n-hexane is larger than the regions in 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane. The cloud-point curve of $PEN_{53}$ in 2,2-dimethyl butane is located at higher temperatures and pressures than the curve in 2,3-dimethyl butane due to the reduced dispersion interactions with and limited access of 2,2-dimethyl butane to the copolymer. Similar cloud-point behavior is observed for $PEN_{53}$ in 2-methyl pentane and 3-methyl pentane.

Cast cake rheology of ash-clay

  • Lee, K.G.;Kim, Y.T.;Kim, J.H.
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1997년도 Proceedings of the 12th KACG Technical Meeting and the 4th Korea-Japan EMGS (Electronic Materials Growth Symposium)
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    • pp.41-44
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    • 1997
  • Dispersion and flocculation behaviors of clay-ash powders in a slurry state were examined, and we have systematically investigated the effects of colloid/interfaces variables on slip properties and the rheological behavior of ash-clay slurry. Ash-clay slurries have been characterized on the basis of the time dependent rheology which was done out by the gel-curve test. Gel-curve for the coagulated slip shows interesting rheological behavior which was caused by the formation of the new network structure and the readsoption of the polysilicon hydroxo species on the particle surfaces.

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Molecular Dynamics Simulation of Contact Process in AFM/FFM Surface Observation

  • Shimizu, J.;Zhou, L.;Eda, H.
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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    • pp.61-62
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    • 2002
  • In order to clarify the contact mechanism between specimen surface and probe tip in the surface observation by the AFM (atomic force microscope) or the FFM (friction force microscope), several molecular dynamics simulations have been performed. In the simulation, a 3-dimensional simulation model is proposed where the specimen and the probe are assumed to consist of mono-crystal line copper and a carbon atom respectively and the effect of cantilever stiffness is also taken into considered. The surface observation process on a well-defined Cu{100} is simulated. The influences of cantilever stiffness on the reactive force images and the behavior of probe tip were evaluated. As a resuIt, several phenomena similar to those observed by the actual surface observation experiment, such as double-slip behavior and dispersion in the stick-slip wave period were observed.

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