Monte Carlo simulation of long-time percolation diffusion on lattices above the threshold

1996 ◽  
Vol 29 (24) ◽  
pp. 7959-7964 ◽  
Author(s):  
O J Poole ◽  
D W Salt
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Long Time

THE INFLUENCE OF A CRITICAL SIZE ON THE SCALING BEHAVIOR OF CLUSTERS COALESCENCE

1999 ◽  
Vol 13 (18) ◽  
pp. 2397-2404 ◽  
Author(s):  
GUOCE ZHUANG ◽  
XIAOBIN ZHU ◽  
WEI WANG
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Cluster Size ◽  
Critical Size ◽  
Simulation Method ◽  
Monte Carlo Simulation Method ◽  
Critical Cluster ◽  
Cluster Aggregation ◽  
Long Time ◽  
Average Size

By introducing a critical cluster size N c , the irreversible and reversible cluster–cluster aggregation are studied with Monte Carlo simulation method. In a long time limit the average size of cluster <S>∞ reaches its stationary value which depends on the critical size N c and the breakup constant k. Our results indicate that in the presence of critical size the critical exponent y, which is defined as <S(k,∞)>~k-y, increases as the critical size increases and is lower than the value of (α+ξ+2)-1, where the exponents α and ξ associate with the detachment and attachment of clusters.

Monte Carlo simulation on the diffusion of polymer in narrow periodical channels

2017 ◽  
Vol 31 (21) ◽  
pp. 1750144 ◽  
Author(s):  
Ying-Cai Chen ◽  
Yan-Li Zhou ◽  
Chao Wang
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Diffusion Process ◽  
Energy Landscape ◽  
Diffusion Constant ◽  
Channel Interaction ◽  
Physical Mechanisms ◽  
Part Formula ◽  
Projected Length ◽  
Long Time

Diffusion of polymer in narrow periodical channels, patterned alternately into part [Formula: see text] and part [Formula: see text] with the same length [Formula: see text], was studied by using Monte Carlo simulation. The interaction between polymer and channel [Formula: see text] is purely repulsive, while that between polymer and channel [Formula: see text] is attractive. Results show that the diffusion of polymer is remarkably affected by the periodicity of channel, and the diffusion constant [Formula: see text] changes periodically with the polymer length [Formula: see text]. At the peaks of [Formula: see text], the projected length of polymer along the channel is an even multiple of [Formula: see text], and the diffusion of polymer in periodical channel is nearly the same as that of polymer in homogeneous channel. While at the valleys of [Formula: see text], the projected length of polymer is an odd multiple of [Formula: see text], and polymer is in a trapped state for a long time and it rapidly jumps to other trapped regions during the diffusion process. The physical mechanisms are discussed from the view of polymer–channel interaction energy landscape.

Prediction of the variability of noise emissions from construction sites using Monte-Carlo simulation

2021 ◽  
Vol 263 (5) ◽  
pp. 1373-1379
Author(s):  
Dave Davis
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Simulation Method ◽  
Construction Site ◽  
Construction Sites ◽  
Noise Sources ◽  
Worst Case ◽  
Time Period ◽  
Long Time ◽  
Energy Average

Noise emissions from construction sites are inherently unsteady. Noise emissions vary due to many causes, including the noise sources frequently changing in location, orientation, the types of activities they perform, and the acoustic shielding due to structures and/or terrain. The noise that arrives at receivers from construction site equipment can fluctuate over all time scales, from seconds to hours, days, months or years. Prediction of noise levels typically assumes either a "worst-case" approach in which all noise sources are assumed to be operating simultaneously, or by predicting an "energy-average" (Leq) level over a long time period. In the latter case, an energy-average (Leq) noise level is predicted at receivers, based on the anticipated percentage utilisation of the various noise sources on the construction site - that is, the fraction of time that each item of equipment is operating or not during the averaging time period. This paper presents a method that may be used to estimate the variability of noise emissions from the site and the corresponding noise immissions at receivers using the Monte-Carlo simulation method. Using this method, the expected minimum, maximum, percentiles and energy-average (Leq) noise immission levels at receivers can be predicted.

Electron Scattering in Solids

1990 ◽  
Vol 48 (2) ◽  
pp. 4-5
Author(s):  
Ryuichi Shimizu ◽  
Ze-Jun Ding
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Angular Distribution ◽  
Elastic Scattering ◽  
Electron Scattering ◽  
Cross Sections ◽  
Expansion Method ◽  
Electron Excitation ◽  
Partial Wave Expansion ◽  
Backscattered Electrons

Monte Carlo simulation has been becoming most powerful tool to describe the electron scattering in solids, leading to more comprehensive understanding of the complicated mechanism of generation of various types of signals for microbeam analysis.The present paper proposes a practical model for the Monte Carlo simulation of scattering processes of a penetrating electron and the generation of the slow secondaries in solids. The model is based on the combined use of Gryzinski’s inner-shell electron excitation function and the dielectric function for taking into account the valence electron contribution in inelastic scattering processes, while the cross-sections derived by partial wave expansion method are used for describing elastic scattering processes. An improvement of the use of this elastic scattering cross-section can be seen in the success to describe the anisotropy of angular distribution of elastically backscattered electrons from Au in low energy region, shown in Fig.l. Fig.l(a) shows the elastic cross-sections of 600 eV electron for single Au-atom, clearly indicating that the angular distribution is no more smooth as expected from Rutherford scattering formula, but has the socalled lobes appearing at the large scattering angle.

Determination of Stoichiometry of GaAs Component in (Gaas)Ge Epitaxially Grown Thin Films by Electron Microprobe X-Ray Analysis

1990 ◽  
Vol 48 (2) ◽  
pp. 264-265
Author(s):  
D. R. Liu ◽  
S. S. Shinozaki ◽  
R. J. Baird
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Compound Semiconductors ◽  
Energy Dispersive Analysis ◽  
X Ray ◽  
Metastable Alloys ◽  
Lower Voltage

The epitaxially grown (GaAs)Ge thin film has been arousing much interest because it is one of metastable alloys of III-V compound semiconductors with germanium and a possible candidate in optoelectronic applications. It is important to be able to accurately determine the composition of the film, particularly whether or not the GaAs component is in stoichiometry, but x-ray energy dispersive analysis (EDS) cannot meet this need. The thickness of the film is usually about 0.5-1.5 μm. If Kα peaks are used for quantification, the accelerating voltage must be more than 10 kV in order for these peaks to be excited. Under this voltage, the generation depth of x-ray photons approaches 1 μm, as evidenced by a Monte Carlo simulation and actual x-ray intensity measurement as discussed below. If a lower voltage is used to reduce the generation depth, their L peaks have to be used. But these L peaks actually are merged as one big hump simply because the atomic numbers of these three elements are relatively small and close together, and the EDS energy resolution is limited.

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