Search results for "Simulation."
showing 10 items of 4779 documents
Novel nanocrystalline cores for EMI suppression in cables: characterization methodology and performance study
2021
El control de las interferencias electromagnéticas (EMI) en dispositivos electrónicos es un problema cada vez mayor al que se enfrentan los diseñadores para garantizar que los dispositivos cumplan con los requisitos de compatibilidad electromagnética (EMC) para operar simultáneamente sin inferir entre sí. Este hecho se debe a la tendencia hacia una mayor integración de componentes, la reducción del tamaño y grosor de las placas de circuito impreso (PCB) y la miniaturización de las carcasas de los dispositivos. Además, otros factores como el empleo de frecuencias de conmutación más altas en los convertidores de potencia y las velocidades de datos de comunicación en los circuitos digitales. C…
Tackling wicked problems in performance management and governance of public health: an empirical analysis of COVID-19 vaccination strategies
2023
PurposePublic health strategies and activities are intrinsically complex. According to the literature, this “wickedness” depends on the different interests and expectations of the stakeholders and the community, the fragmented governance of the related services and the challenges in measuring and assessing public health outcomes. Existent performance measures and management systems for public health are not designed to cope with wickedness since they are mainly focused on inputs and outputs, neglecting broader outcomes because of their long-term impact and the poor accountability of results. This research aims to tackle this shortfall by adopting a dynamic performance management (DPM) appro…
Evaluation des simulations spatiales
2006
The general topic is the evaluation of prospective scenarios for urban planning, especially for the management of urban built up areas. Several models of land-use and land-cover change (LUCC), based on different assumptions, allow producing realistic simulations of urban growth. Three ways can be distinguished for measuring the quality of modelings: 1. The choice of a model and its calibration; 2. The validation (showing if results are realistic); 3. The evaluation (showing if results respect defined planning goals). Measurement methods must be associated to these three steps.
An Automata-Based Cardiac Electrophysiology Simulator to Assess Arrhythmia Inducibility
2022
Personalized cardiac electrophysiology simulations have demonstrated great potential to study cardiac arrhythmias and help in therapy planning of radio-frequency ablation. Its application to analyze vulnerability to ventricular tachycardia and sudden cardiac death in infarcted patients has been recently explored. However, the detailed multi-scale biophysical simulations used in these studies are very demanding in terms of memory and computational resources, which prevents their clinical translation. In this work, we present a fast phenomenological system based on cellular automata (CA) to simulate personalized cardiac electrophysiology. The system is trained on biophysical simulations to re…
Design, Synthesis and Biological Evaluation of Novel Pyrazolo[1,2,4]triazolopyrimidine Derivatives as Potential Anticancer Agents
2021
Three novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations…
Quantification of intracranial contribution to rheoencephalography by a numerical model of the head
2000
Abstract Objectives : Partial contributions of intracranial and extracranial circulation to rheoencephalography (REG) remain uncertain. The main goal of this work is to determine theoretically the capability of REG techniques to reflect intracranial blood flow. Methods : Head and current injection electrodes were computationally modeled to assess REG sensitivity to brain and scalp conductivity changes. Data obtained were related to tissue perfusions to calculate the partial contribution of cerebral blood perfusion to REG I, REG II and monopolar REG and to assess their amplitudes. Results : When REG I and monopolar REG were used, the theoretical maximum of intracranial contribution was reach…
Structural organization of surfactant aggregates in vacuo: a molecular dynamics and well-tempered metadynamics study
2015
Experimental investigations using mass spectrometry have established that surfactant molecules are able to form aggregates in the gas phase. However, there is no general consensus on the organization of these aggregates and how it depends on the aggregation number and surfactant molecular structure. In the present paper we investigate the structural organization of some surfactants in vacuo by molecular dynamics and well-tempered metadynamics simulations to widely explore the space of their possible conformations in vacuo. To study how the specific molecular features of such compounds affect their organization, we have considered as paradigmatic surfactants, the anionic single-chain sodium …
Numerical Simulation of the Kinetics of Radical Decay in Single-Pulse High-Energy Electron-Irradiated Polymer Aqueous Solutions
2019
A new method for the numerical simulation of the radiation chemistry of aqueous polymer solutions is introduced. The method makes use of a deterministic approach combining the conventional homogeneous radiation chemistry of water with the chemistry of polymer radicals and other macromolecular species. The method is applied on single-pulse irradiations of aqueous polymer solutions. The speciation of macromolecular species accounts for the variations in the number of alkyl radicals per chain, molecular weight, and number of internal loops (as a consequence of an intramolecular radical-radical combination). In the simulations, the initial polymer molecular weight, polymer concentration, and do…
Momentum-dependent interfacial tension in polymer solutions
2002
A model for the interface between a concentrated and a very dilute polymer solution is studied by Monte Carlo simulations at temperatures below the Theta temperature (in bad solvent conditions). The wave-number–dependent interfacial tension γ(q) is extracted from an analysis of the capillary wave amplitudes. It is shown that γ(q) decreases monotonically with q2, while no evidence is found for the predicted increase γ(q) ∝ κq2 with a positive bending rigidity κ of the interface at large q. Consequences for the interpretations of simulations and experiments on interfacial widths are briefly discussed.