The reasons for these delays lay in the implementation of the production process as well as in issues that have been overlooked or underestimated beforehand in strategic planning and system design. This is the beginning of the managerial process of structuring, evaluating and deciding options for designing the operating system (see footnote 7), thus providing the framework for operations. Questions and uncertainty about answers are also good indicators of the complexity of the scene.
5 The case was developed during the development of the SIMAS proposal (Simulation as a Service), FP7 FoF-ICT-2013.7.1. In real-time horizons, “optimal” solutions are expected to be valid, i.e. feasible (feasible) and compliant (admissible): given the disadvantages of significant delays, successful attempts to keep the system running are likely to cost the most in most cases. -effective alternative. And in the case of the implementation of a new product, the learning curves are also important when, for example, MGS / Iacobuccy has to deliver a first batch of 20 IHUs - a new product - within 2 months.
The situational (problem-oriented) theory of society, which was developed by heterogeneous actors, contains the knowledge they acquired in the process of investigating the problem situation. Based on this knowledge, actors develop an ontological model of the situation.
Rudnev Inductoheat Inc.,
Usually, the initial temperature of the workpiece before induction heating is uniform and corresponds to the ambient temperature. When the frequency is too high, an induced current is concentrated within a thin surface layer compared to the diameter of the billet requiring long heating times that in progressive induction heating require a longer heating line. It is important that the maximum temperature anywhere inside the billet does not exceed a certain level, ensuring that no areas of the billet are overheated and that "hot shorting" and "burning" of the steel do not occur.
Considering that pyrometers can only reliably measure billet surface temperature at specific locations, there is always a danger of "missing" overheating of the local and/or underground areas. In most publications on progressive induction heating of workpieces, it is strongly recommended to have a graded (profiled) power distribution along the induction line by putting more current at the beginning of the line. Since the system puts more energy into the ingot at the beginning of the heating line, too much energy penetrates into the subsurface area of the ingot in cases where the line runs slowly.
Considering that pyrometers can only reliably measure billet surface temperature, there is always a danger of "missing" an occurrence of subsurface overheating. Many of the advantages of the modular design are due to the ability to control each coil individually.
OPTIMAL CONTROL
OF SYSTEMS WITH THE DISTRIBUTED PARAMETRES ОПТИМАЛЬНОЕ УПРАВЛЕНИЕ СИСТЕМАМИ
С РАСПРЕДЕЛЁННЫМИ ПАРАМЕТРАМИ
Model assumptions
Due to harmonic EM field and induced currents, the Lorentz force can be decomposed into a stable and harmonic part that oscillates with double frequency. Due to larger inertia times for melting compared to the EM field time scale (?/(2B) > 50 Hz), only the stable part of the Lorentz force is considered. Let us consider the non-dimensional frequency Zˆ, which shows the relationship between the induced and external EM field, and the magnetic Reynolds number Rem, which gives the relationship between the generated flow and the external EM field.
Assuming that there is no free charge in the system and displacement currents (no EM wave radiation) are neglected, the reduced Maxwell equation system in combination with simplified Ohm's law (no EM field generation by the flow) is used for harmonic analysis in ANSYS Classic and the Lorentz force distribution in the melt at a certain point in time a free surface shape is obtained. In the HD portion of the calculation, the Navier-Stokes equation for incompressible fluid is solved in ANSYS Fluent.
Model technical implementation
The calculated quasi-steady flow pattern (0 - 55 cm/s) and the density distribution of the Lorentz force (0 - 2.5 MN/m3), as well as the shape of the meniscus in comparison with the experimental data of the meniscus height above the initial planar free surface are shown in Figure 1, b–d. Experimental measurements are marked by the taps, while the vertical lines of the taps correspond to the measurement errors due to the turbulence and mean flow instability that caused free surface fluctuations. The calculated meniscus agrees well with the experiment and the discrepancies obtained are below the measurement error. Regardless of whether the meniscus height is comparable to the initial filling, these experiments cannot demonstrate the similarity between the actual and calculated meniscus shapes.
Therefore, we used experimental measurements of strongly expressed meniscus shapes to further verify the model. a) b) c) d).
Quasi 3D calculation of steady state free surface shape in IFCC
Analytic verification of free surface oscillation period in ICF
In the regions where the magnetic field lines split on the surface of incidence (regions of singularity) the minimum of the Lorentz force is expected due to the small component of the magnetic field parallel to the free surface. Meanwhile, the maximum of the Lorentz force is obtained at the end of the drop due to the largest field intensity and the dominant field component along the free surface. The following distribution of the Lorentz force contributes to the extension of the drop along the magnetic field lines.
In the meantime, the length of the droplet is limited due to the diameter of the quartz tube, the distance between inductor coils or yoke ends. To increase the weight of the floating EM droplets, it is considered to install additional orthogonal horizontal EM field through the technical realization shown in Figure 8. Both inductor coil pairs are supplied with an alternating current of the same frequency and two marginal coil pairs. cases are considered: the phase shift between coaxial coil pairs is @ = 0 and @ = ¢/2. a) b) Figure 8 – (a) - experimental setup [6] and (b) - numerical model of melting EM levitation.
3D numerical results are obtained of the Lorentz force and steady flow on trap cross sections in a dual-frequency EM levitation furnace (Figure 10). fLor, kN/m3 a) . v, m/s b). From the distribution of the Lorentz force it can be clearly noted that in particular orthogonal, non-interacting EM fields with two frequencies, the undesirable singularity of force in the regions with separation of EM field lines is reduced, thus obtaining smaller droplet sizes in the xy -right. The stability of the quasi-stable shape over time, the flat bottom of the drop and a “square” profile in the xy plane correlate well with the experiment.
Current research was carried out with financial support from the ESF project of the University of Latvia, contract no. The main steps of the algorithm include creating the geometry of the induction heating system, mesh generation, description of input data, electromagnetic and thermal analysis. Some results for the simulation of heating of steel cylindrical billets were obtained and compared with results based on FLUX model simulation.
Give a proof of the convexity and compactness of the reachable set of a linear interval dynamical system. This paper focuses on the application of a promising method for quasi-optimal control of process heating/cooling of inhomogeneous media. Heating/cooling can be done using the outer and inner boundaries of a given area of the medium.
An approach to the construction of a soft controller based on a modal representation of a device with distributed parameters is analyzed. Based on this model, a distributed system for automatic control of the temperature of the polymer melt in the dosing zone was synthesized.
MODELLING AND CONTROL
ON COMPLEX STRUCTURED SYSTEMS МОДЕЛИРОВАНИЕ И УПРАВЛЕНИЕ
В СЛОЖНОСТРУКТУРИРУЕМЫХ СИСТЕМАХ
The article deals with the analysis and generalized estimation of the comparative effectiveness of research, the impact of multi-criteria ranking of scientific articles, the disclosure of promising research areas in a large research institution. The method of assessment of a state of the difficult technical systems, based on information on the area boundary about the working capacity presented in an analytical view on the basis of using logical R–functions, is considered. The paper is devoted to the reduction of nonlinear discrete time system with slow and fast variables.
The decomposition algorithm is based on geometric approach and properties of slow and fast invariant manifolds. Presented algorithm makes it possible to create the appropriate in the sense of mean-square criterion models. The proposed method for dynamic object modeling based on the non-parametric estimation of linear and non-linear parts of the system.
The paper describes the structure of an Integrated Customer Service Center (ICSC), its control model and a formal description of the ICSC structural and parametric optimization problem. The article deals with the problem of improving personal performance and the analysis of the characteristics and patterns of its functioning. For this purpose, cognitive linear and non-linear models of creative personality are built.
The creative personality is considered a system triad whose output parameter is the degree of activity obtained in the interaction of all its concepts. Method based on step-by-step mathematical methods using expert processing procedures under conditions of discrepancy and ambiguity. The problem of management is considered by projects dealing with dynamic change of the characteristics of the organizational system.
The general management problem is divided by projects into dynamic scheduling and incentive problems. Algorithms of social transfers and taxation in the dynamic model of the macroeconomic system are considered. The experimental results of the described algorithms affecting the socio-economic indicators of the macroeconomic model have been produced.
