BULLETIN
BULLETIN
of the Yugoslav Simulation Society
Vol. 2, No. 1, June 2000
The main activity of the YSS in the year 2000 is organisation of the Small Systems Simulation Symposium, SSSS2000. This issue of the Bulletin of the YSS is devoted to that forthcoming event. We had responses as expected and we are glad to express the Program committee’s opinion that very high level research papers were submitted. The symposium will take place at the Faculty of Electronic Engineering, University of Ni{, Yugoslavia, on 04-05 September, 2000. Interested readers may find more information at http://yss.elfak.ni.ac.yu. We are looking forward to meeting any interested colleague.
By Slobodan Mijalkovi},
Delft University, The Nederlands
Abstract. It is well known that the standard displacement-based finite element approach to viscoelastic stress analysis in microfabrication technology is susceptible to the volumetric locking and highly oscillatory pressure solutions. As an effective remedy for these problems, a new finite element approach based on separate weak statements for the displacement and pressure is proposed in this paper. Apart from the various existing techniques, the proposed approach is inherently free from the constraints imposed on the selection of discrete approximation spaces and permits a robust and stable discretization based on piecewise linear Galerkin elements. The accuracy and stability of the proposed methodology has been tested in numerical experiments involving stress analysis problems from microfabrication deposition and native film growing processes.
By Zoran S. Nikoli},
University of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
Abstract. In this paper, the time-temperature dependent intergranular impedance model based on intergranular capacitance model and kinetics model is defined. The relations between the most dominant electrical parameters (capacitance and conductance) of the intergranular micro-capacitors, and diffusion equations are established.
By Mirko Jakovljevi} a, Petar A. Fotiub, @eljko Mr~aricac, Van~o Litovskic, Helmut Dettera
a Technical University of Vienna, Institute for Precision Engineering, A-1040 Vienna, Austria
b Technical University of Vienna, Institute for Applied Mechanics, A-1040 Vienna, Austria
c University of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
Conclusions. The examination of the best possible principles for employing all aspects of the electro-thermal microsystem simulation and modeling in a single analogue simulator environment is necessary for fast and reliable simulation in rapid prototyping. It proposes the system-level simulation of different aspects of electro-thermal interactions with other governing physical domains and subsystems, if necessary. The application of analogue simulator with analogue hardware description languages and mixed analogue/digital simulation seems to be promising for this class of engineering problems. The reliability and accuracy of system-level modeling rise with the number of respective factors taken into account. The need for mixed abstraction (multi-level) modeling cannot be underestimated in novel designs, due to controllable complexity of the system-level modeling and support of both, top-down and bottom-up modeling techniques.
By Mahamane Kadera, Michel Lencznera and @eljko Mr~aricab
aEquipe de Mathématiques de Besançon, UMR 6623, Université de Franche-Comté, 16, Route de Gray, F-25030 Besançon Cedex, France
bUniversity of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
Abstract. This paper focuses on the design of distributed control related to distributed mechanical systems. The sensors and actuators are assumed to be numerous and periodically distributed. The problem addressed in this paper is: “ Can we find a way to approximate an optimal control law with a distributed electronic circuit”. Solutions to this problem are proposed in the framework of vibration control using piezoelectric actuators and sensors.
By R.I. Dampera, R.L.B. Frencha and T.W. Scuttb
aImage, Speech and Intelligent Systems Research Group,
Department of Electronics and Computer Science, University of Southampton,
Southampton SO17 1BJ, UK.
bCore
Design Ltd., 55 Ashbourne Road,
Derby DE22 3FS, UK
Abstract. This paper describes the Hi-NOON neural simulator, originally conceived as a general-purpose, object-oriented software system for the simulation of small system of biological neurons, as an aid to the study of links between neurophysiology and behaviour in lower animals. As such, the artificial neurons employed were spiking in nature: to effect an appropriate compromise between computational complexity and biological realism, modelling was at the transmembrane potential level of abstraction. Further, since real neural systems incorporate different types of neurons specialised to somewhat different function, the software was written to accommodate a nonhomogeneous population of neurons. The efficacy of the simulator is illustrated with respect to some recent applications to situated system studies.
By @eljko Mr~arica, Dejan Maksimovi}, Aleksandar Tasi} and Van~o Litovski
University of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
Abstract. Alecsis behavioural simulator and its mixed-signal hardware description language AleC++ form an open simulation environment, where electronic circuits and nonelectrical systems can be analysed. This paper describes some of the features of AleC++ language , namely those that are not in accordance to IEEE standard for VHDL and VHDL-AMS, but are very useful for modeling of complex systems.
By Tihomir R. Ili} a, Kristijan M. Zarkovi} a, Van~o B. Litovskia and Robert I. Damperb
a University of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
bImage, Speech and Intelligent Systems Research Group,
Department of Electronics and Computer Science, University of Southampton,
Southampton SO17 1BJ, UK.
Abstract. In this paper, an idea of modelling dynamic properties of liner electronic circuit by neural network is presented. The aim is that system modelling is simple, so that the simulation time stays in reasonable limits. A neural network is used to black-box model circuit under consideration in time domain. Constraints and limitation of this approach are presented.
By Predrag Petkovi} and Srdjan Djordjevi}
University of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
Abstract. This paper presents a new approach to symbolic analysis of large circuits. We propose a procedure based on matrix-determinant method for circuit function extraction when circuit equations are given by MNA method. The comparison with two other simulator techniques is given using a benchmark example. The overall time reduction in comparison with circuit function extraction in fully expanded form is 25 times.
By Predrag Petkovi} a, Ebrahim Bushehrib, Sr|an Milenkovi} a, Van~o Litovskia
a University of Ni{, Faculty of Electronic Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
bMicroelectronics Centre, Middlesex University, London, UK
Abstract. A functional level simulation as a part of DS modulator (DSM) desing is presented. Parameters that control noise shaping of DSM are describe in details. As desing objective we consider SFDR, stability and sensitivity on mismatch noise.
By Vladimir D. @ivkovi}, Milun S. Jevti}
University of Ni{, Faculty of Electronic
Engineering, Department of Electronics, 18000 Ni{, Yugoslavia
Abstract. Object oriented real-time systems modeling methodology is presented in this paper. The principles of object oriented software-design of real-time systems are described. This methodology answers two main time-critical programmers problems: (1) How to analyze and design concurrent system (like real-time one) and decrease the number of iterations during the software-development process, e.g. to make programming phase straightforward and to make every system-detail known before writing a single line of program code; (2) How to translate object-oriented software-design of real-time system into the real software, which is essentially non-object-oriented.
By Mark Zwolinski
University of Southampton, Dept. of Electronic and Computer Science, UK
Conclusion. A novel algorithm for analogue fault simulation has been described. While the savings in CPU time for the small example circuit given are relatively slight, it has been shown that the technique is valid and that savings are possible. By extending the algorithm to cover larger circuits, substantial savings should be possible.
Monday, September 04
9.30 Registration
10.00 Opening session
Simulation of microelectronic and microelectromechanical systems
10.30 S. Mijalkovi}
A New Finite Element Approach to Stress Analysis inMicrofabrication Technology
11.00 Z. Nikoli}
Simulaton of Intergranular Impedance as a Function of Diffuson Processes
11.30 M. Jakovljevi}, P.Fotiu, @.Mr~arica, V.Litovski, H.Detter
Electro-Thermal Simulation of Microsystems with Mixed Abstraction Modeling
12.00 M. Kader, M. Lenczner, @.Mr~arica
Distributed Control Based on Distributed Electronic Cicuits. Aplication to Vibration Control
12.30 Lunch
Advanced modelling of small systems
14.00 R. Damper, R. French, T. Scutt
The Hi-Noon Neural Simulator and its Applications
14.30 @. Mr~arica, D. Maksimovi}, A. Tasi}, V. Litovski
Some Features of Analogue and Mixed-Signal HDL AleC++
15.00 T.Ili}, K. Zarkovi}, V. Litovski, R. Damper
ANN Application in Modelling of Dynamic Linear Circuit
15.30 P. Petkovi}, S. Djordjevi}
A Hierarchical Approach to Large Circuit Symbolic Simulation
19.00 Symposium dinner
Tuesday, September 05
Simulation and realisation of small systems
10.00 P. Petkovi}, E. Bushehri, S. Milenkovi}, V. Litovski
A High Level Simulation for DS Modulator Design
10.30 V. @ivkovi}, M. Jevti}
An Object Oriented Approach to the Modelling of the Real-Time Systems
11.00 M. Zwolinski
Analogue Fault Simulation Using Device Latency
11.30 Round Table: Simulation of small systems and the role of SSSS.
12.30 Closing the symposium
13.00 Lunch
14.00 Sightseeing tour: Ni{ trough centuries.