• Title/Summary/Keyword: Particle movement

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FRACTAL DIMENSION OF SIMULATED SEDIMENTS (모의류사의 쪽거리 차원)

  • 김형수;윤용남
    • Water for future
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    • v.27 no.3
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    • pp.115-121
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    • 1994
  • Cohesie sediment movement in estuarine systems is strongly affected by the phenomena of aggregation and flocculation. Aggregation is the process where primary particles are clustered together in tightly-packed formations; flocculation is the process where aggregates and single particles are bonded together to form large particle groups of very low specific density. The size, shape and strength of the flocculants control the rate of deposition and the processes of pollutant exchange between suspended sediments and ambient water. In estuarine waters, suspended sediments above the lutocline form the mobile suspension zone while below the lutocline they form the stationary suspension zone. Suspended particles in the mobile zone are generally in a dispersed state and the controlling forces are the Brownian motion and the turbulent flow fluctuations. In the stationary suspension zone, the driving force is the gravity. This paper discusses the settling and particle flocculation characteristics under quiescient flow conditions. Particles are entering the study domain randomly. Particles in the mobile suspension zone are simulated by using the Smoluchowski's model. Flocs created in the mobil suspension zone are moving into the stationary suspension zone where viscosity and drag effects are important. Utilizing the concepts of the maximum Feret's diameter and the Minkowski's sausage logic, the fractal dimension of the flocs within the stationary suspension is estimated and then compared with results obtained by other studies.

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Synthesis and Characterization of Au/TiO2 Nanoparticles with Core-shell Structure (Core-shell 구조의 Au/TiO2 나노 미립자의 합성 및 특성 평가)

  • ;Paul Mulvaney
    • Journal of the Korean Ceramic Society
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    • v.40 no.9
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    • pp.902-908
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    • 2003
  • Au/TiO$_2$ core-shell structure nanoparticles were synthesised by sol-gel process, and the morphology and crystallinity of TiO$_2$ shell were investigated by TEM and UV-Vis. absorption spectrometer. Au/TiO$_2$ core-shell structure nanoparticles could be prepared by the hydrolysis of TOAA (Titanium Oxide Acethylacetonate) in Au colloid ethanol solution with $H_2O$. The thickness of TiO$_2$ shell on the surface of Au particles was about 1 nm. To investigate the crystallinity of TiO$_2$ shell, UV light with 254 nm and radioactive lay of $^{60}$ CO were irradiated on the TiO$_2$ coated Au colloid ethanol solution. The surface plasmon phenomenon of Au nanoparticles appeared only when the radioactive lay was irradiated on the TiO$_2$ coated Au colloid ethanol solution. From these results, it was found that the TiO$_2$ shell was amorphous and the MUA (Mercaptoundecanoic Acid) layer on the Au particle for its dispersion didn't act as an obstacle to disturb the movement of electron onto the surface of Au particle.

Application of Nanoparticles for Materials Recognition Using Peptide Phage Display Technique - Part II: Magnetic Bio-panning Using Fe3O4 Nanoparticles (Peptide phage display 기술을 이용한 나노입자의 materials recognition 응용 - Part II: Fe3O4 나노입자를 이용한 magnetic bio-panning)

  • Lee, Chang-Woo;Kim, Min-Jung;Standaert, R.;Kim, Seyeon;Owens, E.;Yan, Jun;Choa, Yong-Ho;Doktycz, M.;Lee, Jai-Sung
    • Korean Journal of Metals and Materials
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    • v.46 no.3
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    • pp.131-134
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    • 2008
  • The magnetism of$Fe_3O_4$ nanoparticles was applied to magnetic bio-panning process for finding specific sequences against $Fe_3O_4$ crystal phase. Vibrating sample magnetometer (VSM) measurement showed that the coercivity of 30 Oe and the saturation magnetization of 55 emu/g were sufficient in controlling particle movement and magnetizing particles in the media, respectively. This ferrimagnetism of nanoparticles practically enhanced panning efficiency by exaggerating centrifuge step and preventing particle loss. Sequencing results showed that histidine which was commonly found in peptide sequences played an important role in the binding onto $Fe_3O_4$ nanoparticle surface. However, various possible motifs were also observed from several neighboring amino acids of histidine.

Cultural Tunneling Effect: Conceptual adoption & Application in movie industry

  • Roh, Seungkook
    • Asia Marketing Journal
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    • v.16 no.3
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    • pp.77-100
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    • 2014
  • Many researchers have analyzed the relationship between the financial success patterns of a motion picture and many other factors, such as the production cost, marketing, stars, awards, reviews, genre, and rating. Through these studies, many researchers and investors concluded that big budgets to make a blockbuster movie can serve as an insurance policy to meet their ROI; thus the box office is dominated by blockbuster movies. High-budget blockbuster movies are more likely to receive attention because these movies are more recognizable given their high expenses for production and casting. Therefore, audiences choose blockbusters in an effort to reduce the searching cost and to mitigate the possibility of a regrettable choice. This behavior of consumers, in turn, causes distributors to allocate screens for blockbusters, resulting in "concentration of blockbuster consumption." As such, low-budget films cannot easily become popular due to the lack of distribution. Indeed, low-budget films released on a small number of screens often end up becoming dismal failures. However, there are exceptional examples which are contrary to the general idea in the movie industry that a big budget and showings on a large number of screens can guarantee the success of a movie. Although researchers have attempted to analyze the performances of movies with small budgets, such movies are likely to be regarded as outliers and then be entirely discarded, as they are far from the 'three-sigma' range, especially given that previous research methodologies could not explain the financial success of such unique examples. This study attempts to explain the financial success at the box office of low-budget movies by applying the concept of the tunnel effect in quantum mechanics, as the phenomenon found in the movie industry is similar to a particle's movement in quantum physics. The tunneling effect is a phenomenon by which a particle without enough energy to pass over a potential barrier tunnels through it. Adopting the analogy, this study draws a tunneling probability function and cultural constant to forecast other outliers using the Schrödinger equation. Moreover, the study finds that word-of-mouth creates in the movie industry this phenomenon of finding outliers.

Syntactic Structure of English Split Infinitives from the Perspectives of Grammaticalization and Corpus (문법화와 코퍼스의 관점에서 본 영어 분리부정사 통사구조)

  • Kim, Yangsoon
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.3
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    • pp.245-251
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    • 2020
  • From the perspectives of grammaticalization and corpus, the purpose of this study is to examine the motivation of the emergence of the split infinitives in American English and to discuss the justification of the split infinitives based on the corpus empirical data such as COHA and COCA. The formerly ungrammatical split infinitives in the form of [to + adverb + verb] are now definitely grammatical forms in Present Day English (PDE). The corpus-based data confirms the legitimacy of the split infinitives with the empirical reasons like clarifying sentences (i.e., disambiguation) or strongly focused readings. In addition, the split infinitives are natural consequences caused by the grammaticalization of an infinitival particle to and most crucially by the loss of verb movement. When verb movement to T position does not occur in infinitival clauses, the word order results in [to + AdvP + V], thus forming the split infinitives. The split infinitives are no longer a matter of discussion and will continue to increase in both formal and informal contexts as being definitely grammatical forms.

Salt Movement of Soils by Runoff in Green House Area (시설재배지 토양의 유거수에 의한 염류의 이동)

  • Kang, Bo-Koo;Kim, Hyun-Ju;Lee, Kyung-Ja;Kim, Jai-Joung;Hong, Soon-Dal
    • Korean Journal of Environmental Agriculture
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    • v.20 no.2
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    • pp.112-115
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    • 2001
  • Salt accumulation and movement by runoff ware studied in runoff resevior lysimeter constructed in a green house located in the area of Cheongju, Chungbuk province. Average runoff ratio of rainfall within period of this experiment was 58%. The average content of cations lost from field soil by runoff was in the order of $Ca^{2+}(27.12\;mg/L\;)$ > $K^+(9.18\;mg/L)$ > $Mg^{2+}(2.53\;mg/L)$ > $Na^+(1.89\;mg/L)$ and in the care anions $SO_4\;^{2-}(63.38\;mg\;/L)$ > $NO_3\;^-(25.40\;mg/L)$ > $Cl^-(4.19\;mg/L)$ > $PO_4\;^{3-}(3.18\;mg/L)$. Amounts of salt movement by runoff $SO_4\;^{2-}(140.2\;kg/ha)$, $Ca^{2+}(59.9\;kg/ha)$, $NO_3\;^-(56.1\;kg/ha)$, $K^+(20.3\;kg/ha)$, $Cl^-(9.3\;kg/ha)$, $PO_4\;^{3-}(7.0\;kg/ha)$, $Mg^{2+}(5.6\;kg/ha)$ and $Na^+(4.2\;kg/ha)$. The loss amount of $PO_4\;^{3-}$ was the lowest among the anions investigated in this experiment. $P_2O_5$ was accumulated on the soil surface due to strong affinity for the sorption site on the soil particle surface.

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Wind-sand coupling movement induced by strong typhoon and its influences on aerodynamic force distribution of the wind turbine

  • Ke, Shitang;Dong, Yifan;Zhu, Rongkuan;Wang, Tongguang
    • Wind and Structures
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    • v.30 no.4
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    • pp.433-450
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    • 2020
  • The strong turbulence characteristic of typhoon not only will significantly change flow field characteristics surrounding the large-scale wind turbine and aerodynamic force distribution on surface, but also may cause morphological evolution of coast dune and thereby form sand storms. A 5MW horizontal-axis wind turbine in a wind power plant of southeastern coastal areas in China was chosen to investigate the distribution law of additional loads caused by wind-sand coupling movement of coast dune at landing of strong typhoons. Firstly, a mesoscale Weather Research and Forecasting (WRF) mode was introduced in for high spatial resolution simulation of typhoon "Megi". Wind speed profile on the boundary layer of typhoon was gained through fitting based on nonlinear least squares and then it was integrated into the user-defined function (UDF) as an entry condition of small-scaled CFD numerical simulation. On this basis, a synchronous iterative modeling of wind field and sand particle combination was carried out by using a continuous phase and discrete phase. Influencing laws of typhoon and normal wind on moving characteristics of sand particles, equivalent pressure distribution mode of structural surface and characteristics of lift resistance coefficient were compared. Results demonstrated that: Compared with normal wind, mesoscale typhoon intensifies the 3D aerodynamic distribution mode on structural surface of wind turbine significantly. Different from wind loads, sand loads mainly impact on 30° ranges at two sides of the lower windward region on the tower. The ratio between sand loads and wind load reaches 3.937% and the maximum sand pressure coefficient is 0.09. The coupling impact effect of strong typhoon and large sand particles is more significant, in which the resistance coefficient of tower is increased by 9.80% to the maximum extent. The maximum resistance coefficient in typhoon field is 13.79% higher than that in the normal wind field.

Interpretation of Migration of Radionuclides in a Rock Fracture Using a Particle Tracking Method (입자추적법을 사용한 암반균열에서 핵종이동 해석)

  • Chung Kyun Park;Pil Soo Hahn;Douglas J. Drew
    • Nuclear Engineering and Technology
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    • v.27 no.2
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    • pp.176-188
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    • 1995
  • A particle tracking scheme was developed in order to model radionuclide transport through a tortuous flow Held in a rock fracture. The particle tacking method may be used effectively in a heterogeneous flow field such as rock fracture. The parallel plate representation of the single fracture fails to recognize the spatial heterogeneity in the fracture aperture and thus seems inadequate in describing fluid movement through a real fracture. The heterogeneous flow field une modeled by a variable aperture channel model after characterizing aperture distribution by a hydraulic test. To support the validation of radionuclide transport models, a radionuclide migration experiment was performed in a natural fracture of granite. $^3$$H_2O$ and $^{131}$ I are used as tracers. Simulated results were in agreement with experimental result and therefore support the validity of the transport model. Residence time distributions display multipeak curves caused by the fast arrival of solutes traveling along preferential fracture channels and by the much slower arrival of solutes following tortous routes through the fracture. Results from the modelling of the transport of nonsorbing tracer through the fracture show that diffusion into the interconnected pore space in the rock mass has a significant effect on retardation.

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Theoretical Analysis of Chromatographic Peak Asymmetry and Sharpness by the Moment Method Using Two Peptides

  • Choi Du Young;Row Kyung Ho
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.6
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    • pp.495-499
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    • 2004
  • The analyses of peak shapes in chromatography are useful in operating chroma­tographic system. The asymmetry and sharpness of a chromatographic peak are estimated by the reversed-phase adsorption of two standard peptides (angiotensin II bradykinin) on $C_{18}$ In this work, the average particle diameters of $C_{18}$ were 5 and 15 $\mu$m, while the pore sizes were 100 and 300 A. The composition of the mobile phase was $50/50\;vol.\;{\%}$ of a binary mixture of acetonitrile and water with $0.1\%$ TFA, and the particles were packed in a stainless column ($4.6{\times}150$ mm). The third and the fourth central movement were calculated from the chromatographic elution curves by moment analysis. The peak asymmetry was determined by two theoretical calculations: the asymmetry factor by elution peak analysis and skewness with moment analysis. The sharpness was estimated by the fourth central moment. In this work, the most acceptable skewness was calculated when the pore size was 300 A. The large excess was observed on small pore size.

Analgesis of Clearly Reinforced Soil Wall Behavior by Model Test (모형시험에 의한 점성토 보강토벽의 거동분석)

  • 이용안;이재열;김유성
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.11c
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    • pp.85-94
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    • 1999
  • Reinforced Soil Wall has several merits comparing with conventional retaining wall. The conventional method has the limit of wall height, ununiform settlement of the foundation ground, quality assurance of the embankment body, shortening of construction period, economical construction and so on. Basis of previous mentioned things reinforced soil wall is the substitutional method of conventional retaining wall and its necessity is continuously increasing. The embanking material used in reinforced soil wall is generally limited such as a good quality sandy soil, and in many case constructors have to transfer such a good embanking material from far away to construction site. As a result, they would pressed by time and economy. If poor soils could be used embanking material, for example, clayey soil produced in-situ by cutting and excavation, the economical merit of reinforced soil wall would be increased more and more. Likewise, a lot of study about laboratory experimental behavior of reinforced soil wall using a good quality soil is being performed, but is rare study about clayey soil containing much volume of fine particle relatively in korea. In this study, the authors investigated behavior of the geosynthetic reinforced and unreinforced soil walls using clayey soil as embanking material in view of horizontal movement of walls, bearing capacity and reinforcement stress.

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