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This paper describes the ongoing research on the physical modeling of AssiDoman paper mill in Frovi (Sweden). This project includes the developing of a Modelica base library for thermohydraulic, pulp and paper systems. Up to now, the model includes the wet end part of the paper process, that is the approaching system from the mixing chests to the cyclone systems, the headboxes and the wires.

Pulp and paper mill processes have certain typical features in common with other simulation objects. However, computer simulation can serve as a useful tool in the design and construction of process units and the entire mill, as well as comparison of various production and control strategies of the pulp and paper mill processes. Simulation problems in this area are related to the adjustment of simulation models to mill material balances with many recycles. When the internal behaviour of the processes are considered the lack of sufficiently complete or applicable models sets a limitation on simulation studies.

This paper describes a novel function generator and multiplier using digital-to-analog conversion techniques. The device has been designed and built to supplement the existing analog computer facilities at the University of British Columbia. The function generator and multiplier, basically a digital-to-analog converter, is controlled by one ore two punched paper tapes. The device is capable of generating two independent functions specified by the input tapes, their product, and the product of an external variable and one of the tape inputs. All outputs are in analog form with a maximum range of +/- 100 volts and 0.5 % accuracy. Principle of operation, error analysis, circuit diagrams, photographs and test results are included in the paper to illustrate the operation and application of the device.

The goal of this short paper is to describe one possible use of sketches in computer algebra. We show that sketches are a powerful tool for the description of mathematical structures and for the description of computations.

DARE II is a remarkably fast, on-line, all-digital, block-diagram-based simulation system which adds a convenient and inexpensive simulation console to a PDP-9 computer. Block statements, control logic, tabular functions, and data are entered and edited on a CRT keyboard. Solutions appear on a second CRT display and can be plotted or printed out for report preparation. A fully commented program and solution record can be printed out on a teletype and programs may be stored on punched paper tape to be run again at a later date. The DARE II system can be easily programmed to make optimal use of the computer, generating a much faster program than a FORTRAN compiler.

The aim of this paper is to establish the stability results based on the approach of Linear Matrix Inequality (LMI) for the addressed mathematical model using Caputo–Fabrizio operator (CF operator). Firstly, we extend some existing results of Caputo fractional derivative in the literature to a new fractional order operator without using singular kernel which was introduced by Caputo and Fabrizio. Secondly, we have created a mathematical model to increase Cytoplasmic Incompatibility (CI) in Aedes Aegypti mosquitoes by releasing Wolbachia infected mosquitoes. By this, we can suppress the population density of A.Aegypti mosquitoes and can control most common mosquito-borne diseases such as Dengue, Zika fever, Chikungunya, Yellow fever and so on. Our main aim in this paper is to examine the behaviours of Caputo–Fabrizio operator over the logistic growth equation of a population system then, prove the existence and uniqueness of the solution for the considered mathematical model using CF operator. Also, we check the α -exponential stability results for the system via linear matrix inequality technique. Finally a numerical example is provided to check the behaviour of the CF operator on the population system by incorporating the real world data available in the known literature.

This paper studies the delay-dependent conditions for finite-time extended dissipativity based non-fragile feedback control for neural networks with mixed interval time-varying delays. By applying Jensen’s inequality, an extended Jensen’s double integral inequality, and a free matrix form inequality to the Lyapunov–Krasovskii functional (LKF), delay-dependent conditions are derived and solved by the Matlab control toolbox in terms of linear matrix inequalities (LMIs). By stability criteria, this paper is less conservative than the other works. In addition, we demonstrate the advantage of our obtained methods by five numerical examples. One practical example shows a real-world approach: the quadruple-tank process system (QTPS).