Search results for " modeling"
showing 10 items of 2411 documents
Continuum constitutive laws to describe acoustic attenuation in glasses
2020
International audience; Nowadays metamaterials are at the focus of an intense research as promising for thermal and acoustic engineering. However, the computational cost associated to the large system size required for correctly simulating them imposes the use of finite-elements simulations, developing continuum models, able to grasp the physics at play without entering in the atomistic details. Still, a correct description should be able to reproduce not only the extrinsic scattering sources on waves propagation, as introduced by the metamaterial microstructure, but also the intrinsic wave attenuation of the material itself. This becomes dramatically important when the metamaterial is made…
Wavelength-flattened directional couplers for mirror-symmetric interferometers
2005
In the context of guided optics, we derive, analytically and geometrically, a rigorous general criterion to design wavelength insensitive interferometers with mirror symmetry, which are needed for wavelength multiplexing/demultiplexing. The criterion is applied to a practical case, resulting in an interferometer that works on a band wider than 70 nm.
Scaling of non-Markovian Monte Carlo wave-function methods
2004
We demonstrate a scaling method for non-Markovian Monte Carlo wave-function simulations used to study open quantum systems weakly coupled to their environments. We derive a scaling equation, from which the result for the expectation values of arbitrary operators of interest can be calculated, all the quantities in the equation being easily obtainable from the scaled Monte Carlo simulations. In the optimal case, the scaling method can be used, within the weak coupling approximation, to reduce the size of the generated Monte Carlo ensemble by several orders of magnitude. Thus, the developed method allows faster simulations and makes it possible to solve the dynamics of the certain class of no…
On the existence of kinetic equations
1974
The existence of the Boltzmann equation and its generalizations is studied by analysing the order of magnitude of their terms. As a consequence we conclude that the reduced distribution functions are not analytic in the density.
Physiologically-Based Pharmacokinetic/Pharmacodynamic Model of MBQ-167 to Predict Tumor Growth Inhibition in Mice
2020
MBQ-167 is a dual inhibitor of the Rho GTPases Rac and Cdc42 that has shown promising results as an anti-cancer therapeutic at the preclinical stage. This drug has been tested in vitro and in vivo in metastatic breast cancer mouse models. The aim of this study is to develop a physiologically based pharmacokinetic/pharmacodynamic (PBPK-PD) model of MBQ-167 to predict tumor growth inhibition following intraperitoneal (IP) administration in mice bearing Triple Negative and HER2+ mammary tumors. PBPK and Simeoni tumor growth inhibition (TGI) models were developed using the Simcyp V19 Animal Simulator. Our developed PBPK framework adequately describes the time course of MBQ-167 in each of the mo…
Odd haemoglobins in odd-toed ungulates: Impact of selected haemoglobin characteristics of the white rhinoceros (Ceratotherium simum) on the monitorin…
2019
Background Due to the current poaching crisis in Africa, increasing numbers of white rhinoceroses (Ceratotherium simum) require opioid immobilisation for medical interventions or management procedures. Alarmingly, the results of both blood gas analysis and pulse oximetry regularly indicate severe hypoxaemia. Yet, the recovery of the animals is uneventful. Thus, neither of the techniques seems to represent the real oxygenation level. We hypothesized that unusual haemoglobin characteristics of this species interfere with the techniques developed and calibrated for the use in human patients. Methods Haemoglobin was isolated from blood samples of four adult, white rhinoceroses. Oxygen dissociat…
The impact of grain size on the efficiency of embedded SIMD image processing architectures
2004
Pixel-per-processing element (PPE) ratio-the amount of image data directly mapped to each processing element-has a significant impact on the area and energy efficiency of embedded SIMD architectures for image processing applications. This paper quantitatively evaluates the impact of PPE ratio on system performance and efficiency for focal-plane SIMD image processing architectures by comparing throughput, area efficiency, and energy efficiency for a range of common application kernels using architectural and workload simulation. While the impact of grain size is affected by the mix of executed instructions within an application program, the most efficient PPE ratio often does not occur at PE…
<title>Spectral/spatial integration effects on information extraction from multispectral data: multiresolution approaches</title>
1995
New techniques for information extraction from multispectral data require physical modeling to understand the energy transfer at the atmosphere/surface interface and to develop appropriate inversion procedures, in combination with advanced processing techniques. A multi-step procedure is proposed in this work: the first step implies a binary decision about the second step to be applied in each case. If the pixel is considered as being a `pure' pixel, through a spectral/spatial classification procedure based on multiresolution techniques, then numerical inversion techniques, based on a multiple-scattering reflectance model, are used to extract parameters representing specific surface propert…
Accentuating the Positive, Eliminating the Negative? Relationship Maintenance as a Predictor of Two-Dimensional Relationship Quality
2012
In this study, relationship maintenance and its connections with positive and negative relationship quality were examined among Finnish parents (N = 177 women and 153 men; i.e., partners from 150 couples and 27 women and 3 men whose partner did not participate in the study). Relationship maintenance was measured using Stafford, Dainton, and Haas's (2000) version of the RMSM and two-dimensional relationship quality using Fincham and Linfield's (1997) PANQIMS. Structural equation modeling was utilized to analyze paired data. Women were found to report more relationship maintenance behaviors than their partners. The results showed further that relationship maintenance was connected with both p…
Czy Nysius huttoni (Hemiptera: Heteroptera: Lygaeidae), gatunek obcy dla Europy, może mieć w Polsce sprzyjające warunki do bytowania?
2020
Nysius huttoni, the species endemic to New Zealand, is regarded as a pest which feeding can seriously reduce crop establishment in forage brassicas. It was discovered for the first time in Europe in 2002 (the Netherlands) and has spread in several European countries (Belgium, France, United Kingdom, Germany). Although detailed data on the natural spread of N. huttoni is lacking, it can theoretically be transported over long distances with infested plants, and is often found on apple and kiwi fruit packages exported from New Zealand. The species was hitherto not reported from Poland, therefore its potential geographic distribution was modelled using maximum entropy (Max-Ent) in order to pred…