Search results for "Modeling and Simulation"
showing 10 items of 1561 documents
Past, Present and Future of Process Control at Xstrata Nikkelverk
2009
MIC celebrates its 30th anniversary in 2009 and Xstrata Nikkelverk celebrates its 100th anniversary in 2010. Both anniversaries are certainly worth celebrating and with this article Xstrata Nikkelverk salutes MIC at this special occasion. This article is about process control developments at Xstrata Nikkelverk during the last 40 years. We also give an overview of the current status and a view on the current and future trends of process control at the Nikkelverk renery.
daptive Backstepping Control of Nonlinear Hydraulic-Mechanical System Including Valve Dynamics
2010
Published version of an article from the journal: Modeling Identification and Control. Also available from publisher: http://dx.doi.org/10.4173/mic.2010.1.3 The main contribution of the paper is the development of an adaptive backstepping controller for a nonlinear hydraulic-mechanical system considering valve dynamics. The paper also compares the performance of two variants of an adaptive backstepping tracking controller with a simple PI controller. The results show that the backstepping controller considering valve dynamics achieves significantly better tracking performance than the PI controller, while handling uncertain parameters related to internal leakage, friction, the orifice equat…
Finite element analysis of two total knee joint prostheses
2012
Aim of this work is to compare two different total knee prostheses that differ mainly in the shape of the polyethylene (PE) component inserted between the femoral and tibial plates. The best solution between them has been originally reshaped in order to reduce stress peaks. The study procedure has been divided into the following steps. First step is the digitalisation of the shape of the prostheses by means of a 3D laser scanner. The morphology of two prototypes of the prostheses has been acquired by elaborating multiple Moire fringe patterns projected on their surfaces. Second step consisted on the manipulation of these data in a CAD module, that is the interpolation of raw data into NURBS…
Emergent behaviors and scalability for multi-agent reinforcement learning-based pedestrian models
2017
This paper analyzes the emergent behaviors of pedestrian groups that learn through the multiagent reinforcement learning model developed in our group. Five scenarios studied in the pedestrian model literature, and with different levels of complexity, were simulated in order to analyze the robustness and the scalability of the model. Firstly, a reduced group of agents must learn by interaction with the environment in each scenario. In this phase, each agent learns its own kinematic controller, that will drive it at a simulation time. Secondly, the number of simulated agents is increased, in each scenario where agents have previously learnt, to test the appearance of emergent macroscopic beha…
Modeling and simulation of a VCM micromotor and its potential applications
2013
This paper presents the modeling and simulation of a VCM electrostatic micromotor with a new FEM analysis and implementation method, in order to determine the electrical parameters of the model and the generated electrostatic torque. Both the modeling and the simulation have been achieved using several software programs. In particular, the geometric model created with AUTOCAD has been imported to the FEMM program for the finite-element-method analysis. Then, with the LUA and MATLAB simulation programs, the parameters of the model and the related electrostatic torque have been calculated. The results obtained from this work have been compared with those reported in other scientific papers, s…
Validation of portable 2D force binding systems for cross-country skiing
2013
The aim of the present study was to design, construct and scientifically validate a two-dimensional force measurement binding system for cross-country skiing. The system consists of two force measurement bindings. One binding was designed for analysing classic skiing (vertical and anterior–posterior [along the ski] force components) and the other one for skate (freestyle) skiing (vertical and medio-lateral [transverse to the ski] force components). Validation was accomplished using a three-step process: (1) accuracy tests for the sensors in two temperatures, (2) sport-specific imitation jump test on standard force plates in a laboratory and (3) comparing the system against force measurement…
Assessment methods for impact of environmentally friendly entrepreneurship and driving forces to the quality of environment
2002
Environmentally friendly entrepreneurship (further – EFE) is one of the tools for improvement environmental quality. There might be made theoretical approaches, how quantitatively large is the impact of the EFE in changes of the quality of environment. In this field theoretical suggestion is prior to practice, because in the most of countries there is domination of several cases, but it could not be used as overall tendency [8; 10]. Opposite impact to quality of environment might be created by driving forces (driving forces are economical indicators, which stimulate changes in quality of environment) [1] like overcon‐sumption, growth of gross domestic product (further – GDP) etc. The articl…
Nonlinear extended thermodynamics of a dilute nonviscous gas
2002
This paper deals with further developments of a nonlinear theory for a nonviscous gas in the presence of heat flux, which has been proposed in previous papers, using extended thermodynamics. The fundamental fields used are the density, the velocity, the internal energy density, and the heat flux. Using the Liu procedure, the constitutive theory is built up without approximations and the consistence of the model is showed: it is shown that the model is determined by the choice of three scalar functions which must satisfy a system of partial differential equations, which always has solutions. Different changes of field variables are carried out, using different Legendre transformations, passi…
A Simulation-Based Failure Mode Analysis of SARS-CoV-2 Infection Control and Prevention in Emergency Departments
2020
Background Severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19)] outbreak has been declared a global pandemic by the World Health Organization. The COVID-19 pandemic has highlighted problems of sustainable infection prevention and control measures worldwide, particularly the emerging issues with an insufficient supply of personal protective equipment. The aim of this study was to provide an action plan for mitigation of occupational hazards and nosocomial spread of SARS-CoV-2 through a failure mode analysis based on observations during in situ simulations. Methods A multicenter, cross-sectional, observational, simulation-bas…
Smooth and non-smooth traveling wave solutions of some generalized Camassa–Holm equations
2014
In this paper we employ two recent analytical approaches to investigate the possible classes of traveling wave solutions of some members of a recently-derived integrable family of generalized Camassa-Holm (GCH) equations. A recent, novel application of phase-plane analysis is employed to analyze the singular traveling wave equations of three of the GCH NLPDEs, i.e. the possible non-smooth peakon, cuspon and compacton solutions. Two of the GCH equations do not support singular traveling waves. The third equation supports four-segmented, non-smooth $M$-wave solutions, while the fourth supports both solitary (peakon) and periodic (cuspon) cusp waves in different parameter regimes. Moreover, sm…