The numerical modelling in plasma physics as well as in microwave devices or accelarator technology, requires highly accurate charged particle beam simulations, which have to be in particular well adapted to the geome...
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ISBN:
(纸本)0889864691
The numerical modelling in plasma physics as well as in microwave devices or accelarator technology, requires highly accurate charged particle beam simulations, which have to be in particular well adapted to the geometrical complexity of real devices. Moreover, in order to be able to select between several issues in the design of high power microwave devices, we were led to prospect new techniques to numerically approach realistic 3-D geometries. In order to take into account the 3-D effects, we have investigated a numerical method for solving the 3-D time dependent Vlasov-Maxwell equations on unstructured meshes, based on a conforming finite element formulation. We present some numerical results obtained on 3-D devices.
This paper provides a novel modelling approach to nonlinear system modelling. This model is based on modal series model of nonlinear systems and it is very beneficial for nonlinear system identification since it intro...
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ISBN:
(纸本)0889864691
This paper provides a novel modelling approach to nonlinear system modelling. This model is based on modal series model of nonlinear systems and it is very beneficial for nonlinear system identification since it introduces a linear and several Hammerstein subsystems for the main nonlinear system. Therefore, identification problem of a nonlinear system reduces to identification of a linear subsystem and several Hammerstein subsystems that all have the same linear block and the structure of their nonlinear blocks are distinct. In order to identify the proposed model, an algorithm based on linear subspace identification methods has been proposed. simulations are used to evaluate the results of what argued in this paper.
Among the stages of a simulation project life cycle the model development phase is the longest. Two major reasons for the lengthiness are the lack of understanding of the system by the modeller and the difficulty in p...
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ISBN:
(纸本)0889864691
Among the stages of a simulation project life cycle the model development phase is the longest. Two major reasons for the lengthiness are the lack of understanding of the system by the modeller and the difficulty in programming. Many researchers have tried to accelerate the process mainly by improving the programming efficiency. However these approaches do not guarantee that the model developed in a shorter time is the model which represents the actual physical model. Under the proposed approach a software tool will allow the modeller to develop a conceptual model of the system in the user domain independently of any simulation language. Once the conceptual model is finalized it is automatically translated into the computer simulation model. This will reduce the time needed to produce a valid model as well as to verify the developed computer model.
In project management practice there are several consolidated methodologies that can be applied to help managers: ranging from PERT to CPM and from S curve analysis to complex software application the field of researc...
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In project management practice there are several consolidated methodologies that can be applied to help managers: ranging from PERT to CPM and from S curve analysis to complex software application the field of research seems to be completely explored. Unfortunately in common practice no one of the mentioned technique can be applied easily since the level of detail requested for applying such methodologies is simply too high to be adopted, the resulting practice is, generally, left to the Project Office initiative resulting approximation and lack of control among raising costs. In order to give a formal approach to the problem the authors proposes a simulation based approach in which critical process are top down modeled resulting in a general improvement of the control effectiveness. In the paper this new methodology is described and applied to a real industrial case as well as results discussed.
In this paper, an experimental optimal mechanical ventilation system, consists of the Human Respiratory Control Simulator, second version of ventilation apparatus MV2, an artificial lung, and the Analysis Plus!™ monit...
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ISBN:
(纸本)0889864691
In this paper, an experimental optimal mechanical ventilation system, consists of the Human Respiratory Control Simulator, second version of ventilation apparatus MV2, an artificial lung, and the Analysis Plus!™ monitoring interface, was implemented and simulated. The ventilation device MV2 is interfaced by a data acquisition card and driven by the optimal airflow profile that was optimized by the simulator. In an earlier design MV1 which was restricted due to some elements, it was found that the optimized airflow profile couldn't be achieved thoroughly. The MV2 was implemented to improve the system errors and to complete the active mode of control through the entire respiratory cycle. The fulfillment of current integrated system is expected to close the gap between experimental apparatus and future clinical needs. Furthermore, an intelligent feedback controller for any ventilator is essentially needed in further studies.
Particle migration and cake formation in a centrifugal filter basket under various rotating speeds are simulated using a Lagrangian-Eulerian model. The velocities and trajectories of particle in the filter basket are ...
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ISBN:
(纸本)0889864691
Particle migration and cake formation in a centrifugal filter basket under various rotating speeds are simulated using a Lagrangian-Eulerian model. The velocities and trajectories of particle in the filter basket are analyzed based on the Newton's second law of motion and the hindered settling theory. The variations of the interfaces between clear liquid, suspension and filter cake during a filtration are then simulated. The simulated results of particle concentration profiles in the filter basket show that a uniform concentration exists in the middle region of the filter basket during the centrifugal filtration with a low rotating speed. The sedimentation effect of particles may result in a heterogeneous filter cake. More larger particles deposit in the region near the filter medium, while finer particles deposit near the cake surface. An increase in the rotating speed leads to a more heterogeneous cake. The effect of rotating speed on the particle size distribution in cake is also discussed.
Built from a need for modelling cognitive processes, a modular neural network is designed as the "brain" of a virtual robot moving in a prey-predator environment. The robot decides its path from the animals ...
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Built from a need for modelling cognitive processes, a modular neural network is designed as the "brain" of a virtual robot moving in a prey-predator environment. The robot decides its path from the animals it identifies around. Both a parallel implementation of distributed processes and a temporal coding of spiking neurons allow the robot to develop multimodal' perception with attentional mechanisms and to react in real-time to its dynamic environment.
The case of submarine rendez-vous where a high-manoeuvrability AUV should meet a submarine platform for energy, samples and data service is considered. The AUV has a set of thrusters. It is difficult to know how to ac...
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ISBN:
(纸本)0889864691
The case of submarine rendez-vous where a high-manoeuvrability AUV should meet a submarine platform for energy, samples and data service is considered. The AUV has a set of thrusters. It is difficult to know how to activate the thrusters for the rendez-vous operation. A simulation is developed to consider several scenarios, with submarine obstacles, and to solve the control problem. Genetic algorithms are used to determine the best AUV trajectory from surface to the final state, and to obtain the best control planning, using the thrusters, for path following along the trajectory. This paper describes the problem and the solution in simulation. Several scenarios are considered, and the solutions are presented. The simulation system will be used for programming a real AUV before diving.
A new concept for model of spin (in contrast to traditional electron as rotating ball) has been developed. On the basis of this concept we can describe and interpret not only processes from quantum mechanics, but also...
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ISBN:
(纸本)0889865248
A new concept for model of spin (in contrast to traditional electron as rotating ball) has been developed. On the basis of this concept we can describe and interpret not only processes from quantum mechanics, but also from cosmology. This concept might be useful for GUT as well, because spin like property of matter described here, is alternative concept to superstrings.
Ergonomics is an interdisciplinary area that integrates technical, medical and fundamental sciences. As in other sciences, scientific development in ergonomics, formerly based on the conventional iteration of the &quo...
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ISBN:
(纸本)0889864691
Ergonomics is an interdisciplinary area that integrates technical, medical and fundamental sciences. As in other sciences, scientific development in ergonomics, formerly based on the conventional iteration of the "theory-experimentation" dyad, is being replaced the iteration of the "theory-experimentation-simulation" triad, simulation meaning experimentation done using a mathematical model implemented in a computer software environment. What simulation methods are used in ergonomics, and what is their scope of application? This paper is an attempt to address this question. And since the essence of ergonomics lies in analysing the mutual relationships between man and machine, the main focus is on the modelling of man. In view of the degree of the problem's complexity, the authors of the paper believe that the particular type of the machine linked with man in such a relationship must be likewise taken into account. Such "machines" include technical means of transport (road and rail vehicles, aircraft). The paper analyses the following simulation models of man: anthropometrical models, biomechanical models (including original proprietary biomechanical models), heuristic models (including proprietary models). One important process in the development of simulation models is their identification and verification. This process can take on a different character depending on the type of the model.
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