Search results for "Dynamic model"

Modelling and simulation of several interacting cellular automata

2015

Cellular automata are used for modelling and simulation of many systems. In some applications, the system is formed by a set of subsystems that can be modelled separately, but, in such cases, the existence of interactions between these subsystems requires additional modelling and computer programming. In this paper we propose a modelling methodology for the simulation of a set of cellular automata models that interact with each other. The modelling methodology is described, together with an insight on implementation details. Also, it is applied to a particular cellular automata model, the Sanpile model, to illustrate its use and to obtain some example simulations.

Development, modeling and simulation of test equipment for subsea choke valves

2014

Masteroppgave i mekatronikk MAS 500 Universitetet i Agder 2014 As a step toward being more e_ective and to improve test procedures, GE Oil & Gas wants to develop a workshoptool to automate the testing of Choke Valves. The Choke Valve Workshop Tool (CVWT) main functionis to operate the Hydraulic Stepping Actuator automatically by providing controlled pressure pulses. Electricaland hydraulic equipment will have an interface allowing the test equipment to be connected and used on awide range of Choke Valves. Test results will be transferred and stored automatically based on current need. Adetailed description of the planned CVWT including a complete control system and a Human Machine Interface…

Exploiting Valve Timing for Pneumatic Energy Savings

2018

This research paper aims at addressing solutions that reduce air consumption in generic pneumatic systems used for pick-and-place operations. The investigation considers different system architectures both with a single control valve and two control valves arranged according to an independent metering configuration. Suitable control strategies are then proposed exploiting multiple timings to shut off the non-proportional switching valve(s). The resulting scenarios are experimentally evaluated on a dedicated test-bed. The main conclusion is that reduction of air consumption up to 73% is possible in comparison to the state-of-the-art layout for the reference application. Numerical simulations…

Integrated thermodynamic and electrical modelling of a variable-speed reversible heat pump: analysis of the cooling mode operation

2022

Variable-speed reversible heat pumps are increasingly adopted for space heating and cooling in residential and tertiary sectors. It is recognized that these systems will play a key role in medium- and small-scale 4th generation district heating and cooling networks. Indeed, with the high penetration of intermittent renewable energy sources, such technology could help reduce issues related to the surplus of electricity from renewable energy sources by converting it into heat or cold. To reliably assess the benefits achievable in these emerging applications, it is necessary to develop models which can simulate not only the steady-state operation but also the dynamic response of the system wit…

The influence of the temperature on the liquid–liquid equlibria of the mixture limonene + ethanol + H2O

2004

Abstract In this work, experimental liquid–liquid equilibria (LLE) of the limonene + ethanol + water system are presented. The LLE of this system has been measured at 293.15, 303.15, 313.15 and 323.15 K. The equilibrium data presented are correlated using NRTL and UNIQUAC equations. Finally, the reliability of these models is tested by comparison with experimental results.

Simulating residential changes using an individual-based dynamic model (Mobisim) - An application on the urban agglomeration of Besançon (France)

2012

Predicting human performance in interactive tasks by using dynamic models

2017

The selection of an appropriate sequence of activities is an essential task to keep student motivation and foster engagement. Usually, decisions in this respect are made by taking into account the difficulty of the activities, in relation to the student's level of competence. In this paper, we present a dynamic model that aims to predict the average performance of a group of students at solving a given series of maths problems. The system takes into account both student- and task-related features. This model was built and validated by using the data gathered in an experimental session that involved 64 participants solving a sequence of 26 arithmetic problems. The data collected from the fir…

A procedure for predicting sorption equilibrium in ternary polymer systems from Flory–Huggins binary interaction parameters and the inversion point o…

1989

A procedure has been developed, based on the Flory–Huggins theory as generalized by Pouchlý, which permits the calculation of preferential (λ) and total (Y) sorption coefficients from previous information on the binary interaction parameters, χ, χ, and g12(ϕ10) and on the mixture composition at which the sign of λ inverts. The expressions obtained were applied to 10 cosolvent polymer systems for which experimental values of λ and Y are known. Practically in all the studied systems, the theoretical predictions are in fair accordance with the experimental data.

Temperature dependence of η / s of strongly interacting matter: Effects of the equation of state and the parametric form of ( η / s ) ( T )

2020

We investigate the temperature dependence of the shear viscosity to entropy density ratio η/s using a piecewise linear parametrization. To determine the optimal values of the parameters and the associated uncertainties, we perform a global Bayesian model-to-data comparison on Au+Au collisions at √sNN=200 GeV and Pb+Pb collisions at 2.76 TeV and 5.02 TeV, using a 2+1D hydrodynamical model with the Eskola-Kajantie-Ruuskanen-Tuominen (EKRT) initial state. We provide three new parametrizations of the equation of state (EoS) based on contemporary lattice results and hadron resonance gas, and use them and the widely used s95p parametrization to explore the uncertainty in the analysis due to the c…

Transient stability simulation of a fixed speed wind turbine by Matlab/Simulink

2007

This paper describes the dynamic behavior of a typical fixed speed wind turbine connected to the grid; the model is developed in the simulation tool Matlab/Simulink and created as a modular structure. The pitch control system is used for stabilization of the wind turbine at grid faults. In this way, voltage stability of the system with grid-connected wind turbines can be improved by using blade-angle control for a temporary reduction of the wind turbine power during a short-circuit fault in the grid. This paper shows a new variable control for maintaining of voltage stability, when a three-phase fault is applied close to the wind turbine and cleared by disconnecting the affected line. In th…