Search results for "Monte Carlo method"
showing 10 items of 1234 documents
Partially Reversible Adsorption of Annexin A1 on POPC/POPS Bilayers Investigated by QCM Measurements, SFM, and DMC Simulations
2005
The kinetics of annexin A1 binding to solid-supported lipid bilayers consisting of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoserine (POPS; 4:1) has been investigated as a function of the calcium ion concentration in the bulk phase. Quartz crystal microbalance measurements in conjunction with scanning force microscopy, fluorescence microscopy, and computer simulations indicate that at a given Ca2+ concentration annexin A1 adsorbs irreversibly on membrane domains enriched in POPS. By contrast, annexin A1 adsorbs reversibly on the POPC-enriched phase, which is composed of single POPS molecules embedded within a POPC matrix. The overall are…
Biologically inspired information processing and synchronization in ensembles of non-identical threshold-potential nanostructures.
2013
Nanotechnology produces basic structures that show a significant variability in their individual physical properties. This experimental fact may constitute a serious limitation for most applications requiring nominally identical building blocks. On the other hand, biological diversity is found in most natural systems. We show that reliable information processing can be achieved with heterogeneous groups of non-identical nanostructures by using some conceptual schemes characteristic of biological networks (diversity, frequency-based signal processing, rate and rank order coding, and synchronization). To this end, we simulate the integrated response of an ensemble of single-electron transisto…
A Simple Monte Carlo Model of a Hot Carrier Cell
2017
In the present work, a simplified model of a hot carrier cell is examined at different energy levels of carrier collection. Incident photons, Monte Carlo generated by employing the ASTM G173–03 data set, are accounted for individually as they interact with the cell. The hot carrier cells are examined in a transient state caused by a flash of photons with AM1.5 spectrum. Excess photon energy is recycled giving a form of thermalization of hot carriers. The sensitivity of contact variables and the device band gap on cell efficiency, has been studied.
Air Traffic, Boarding and Scaling Exponents
2014
The air traffic is a very important part of the global transportation network. In distinction from vehicular traffic, the boarding of an airplane is a significant part of the whole transportation process. Here we study an airplane boarding model, introduced in 2012 by Frette and Hemmer, with the aim to determine precisely the asymptotic power–law scaling behavior of the mean boarding time 〈t b 〉 and other related quantities for large number of passengers N. Our analysis is based on an exact enumeration for small system sizes N ≤ 14 and Monte Carlo simulation data for very large system sizes up to \(N = 2^{16} = 65,536\). It shows that the asymptotic power–law scaling 〈t b 〉 ∝ N α holds with…
Urban runoff modelling uncertainty: Comparison among Bayesian and pseudo-Bayesian methods
2009
Urban stormwater quality modelling plays a central role in evaluation of the quality of the receiving water body. However, the complexity of the physical processes that must be simulated and the limited amount of data available for calibration may lead to high uncertainty in the model results. This study was conducted to assess modelling uncertainty associated with catchment surface pollution evaluation. Eight models were compared based on the results of a case study in which there was limited data available for calibration. Uncertainty analysis was then conducted using three different methods: the Bayesian Monte Carlo method, the GLUE pseudo-Bayesian method and the GLUE method revised by m…
Parallelization of adaptive MC integrators
1997
Monte Carlo (MC) methods for numerical integration seem to be embarassingly parallel on first sight. When adaptive schemes are applied in order to enhance convergence however, the seemingly most natural way of replicating the whole job on each processor can potentially ruin the adaptive behaviour. Using the popular VEGAS-Algorithm as an example an economic method of semi-micro parallelization with variable grain-size is presented and contrasted with another straightforward approach of macro-parallelization. A portable implementation of this semi-micro parallelization is used in the xloops-project and is made publicly available.
Fatigue life estimation for 30CrNiMo8 steel under in- and out-of-phase combined bending and torsion with variable amplitudes
1996
Fatigue life successively calculated according to three criteria of multiaxial fatigue for randomly varying loading is compared with fatigue life obtained by Sanetra and Zenner in testing cylindrical specimens of 30CrNiMo8 steel by in- and out-of-phase bending and torsion with variable amplitudes. The position of the plane of fatigue fracture is determined using the variance method. The histories of equivalent stresses are schematically represented by the Monte Carlo method. Fatigue damage was computed using the Palmgren-Miner hypothesis. The most realistic estimates of fatigue life in the scatter band of the results with a factor of 3 are obtained on the basis of the criterion of maximum t…
Direct evaluation of the equivalent linear damping for TLCD systems in random vibration for pre-design purposes
2014
Abstract Passive control of structural vibrations has received in recent years a great attention from researchers concerned with vibration control. Several types of devices have been proposed in order to reduce the dynamic responses of different kinds of structural systems. Among them, the Tuned Liquid Column Damper (TLCD) proved to be very effective in reducing vibration of structures. Since the increasing use of TLCDs in practical realizations, this paper aims at developing an approximate formulation, by means of a statistical linearization technique, able to estimate the parameters of a structure equipped with a TLCD subjected to random loads for pre-design purposes. Moreover, it is show…
A probabilistic approach to radiant field modeling in dense particulate systems
2016
Radiant field distribution is an important modeling issue in many systems of practical interest, such as photo-bioreactors for algae growth and heterogeneous photo-catalytic reactors for water detoxification.In this work, a simple radiant field model suitable for dispersed systems showing particle size distributions, is proposed for both dilute and dense two-phase systems. Its main features are: (i) only physical, independently assessable parameters are involved and (ii) its simplicity allows a closed form solution, which makes it suitable for inclusion in a complete photo-reactor model, where also kinetic and fluid dynamic sub-models play a role. A similar model can be derived by making us…
Spinodal decomposition of a two-dimensional model alloy with mobile vacancies
1991
Abstract Monte Carlo simulations are performed for the initial stages of phase separation in a model binary alloy (AB), where unmixing is caused by a repulsive energy between atoms of different kind ( e AA = e BB = e ), and a small fraction c v of mobile vacancies is present (typically c v = 0.04.) Unlike previous work, where interdiffusion was modelled in an unrealistic way by direct interchange of A and B atoms for c v = 0, were use the vacancy mechanism of diffusion: A-atoms may jump to vacant sites with a rate Γ A and B-atoms may jump to vacant sites with a rate Γ B , no direct A–B interchange being permitted. It is shown that the overall time-scale on which phase separation proceeds ty…