Control of Zeros and Poles in Problems of Synthesis of Regulation Systems. Part I. Compensation Approach

A highly important place in the theory and practice of automatic systems occupy the problems of synthesis of automatic regulation systems (ARS) based on the requirements for the dynamic quality of regulation processes. For class of linear stationary ARS such requirements are imposed upon the type and parameters of its transition characteristic which is uniquely determined by its transfer function (TF). In this connection the setting of problem of ARS synthesis with desired TF, corresponding to the given amplification coefficient, zeros and poles of the synthesized system is regularity. The given problem is worth while to call as the control problem of zeros and poles of ARS. In the present paper consists into two parts, the questions of control of zeros and poles ARS, which are important for engineering applications are considered. A critical analysis of the known compensation and compensation-modal regulation schemes is given. And also the new circuit solutions combining the functionality possibilities of compensation and modal approaches are proposed. The first part of the article the effect of compensation of zeros and poles of control objects in ARS is analyzed. The understanding of this effect gives the representation of the system of canonical structure of R. Kalman, according to which the compensation of zeros and poles of object does not mean their physical liquidation. As a result of compensation, they become the poles of its unobservable and unmanageable parts, which will be tell upon the regulation processes in the conditions of disturbances of the state of control object. The given effect and its negative results are clearly detected in the classical method of constructing of controllers on a priori given (desired, reference) TF of closed ARS. The influence of the factor of non-minimal phase zeros on the dynamics of control systems is studied. The effect of negative ejection in the transition characteristic of the system is described and its quantitative assessment is given for the case of a single real right zero. In the second part of the article the well-known methods for ARS synthesis with desired TF, based on use of polynomial calculus apparatus are considered and analyzed. New compensatory modal methods which may be of interest in engineering applications are proposed.

Dynamics of a Moulding Cooling at Injection of Plastics

For a regulation of moulding cooling time course in a mould it is necessary to derive an equation of the mould temperature dependence on the moulding temperature as the equation of the regulation system. Amplitude, phase and transition characteristic are for R=1 and P=1 identical as for the action quantity. Amplitude, phase and transition characteristic of the action quantity and the control of the regulation circuit at use of the proportional regulator show that the circuit is stable a periodic. From the amplitude, phase and transition characteristic of the regulation circuit defect it is seen that the defect in the regulation circuit is relatively fast lowered. From the mentioned conclusions it is seen that the moulding cooling in the mould at injection of plastics with the proportional regulator introduces the regulation with relatively favourable regulation properties.

Electronic Structure Tuning and Interface Charge Transfer in Hybrid Graphene/Titania and Adatom/Graphene/Titania: First Principles Calculations

Firstly, density functional calculation was employed to evaluate the electronic structure of graphene/TiO2(100) composite. The results demonstrated that lattice mismatch between graphene and the titania surface brought about apparent modification to the crystal structure and electronic structure of graphene. Additionally, graphene adsorbed with several different adatoms were combined with the titania surface. The effects of the adatoms on the electronic structure and electron transition characteristic of the complex of adatom/graphene/TiO2(100) were evaluated. The results indicated that the adatoms of B and Al shifted the DOS minimum of graphene to the lower energy side of the Fermi level while N, S, F, Pt and Au caused the opposite effect. The adatoms of Pd, Cr and Mn exhibited no obvious effect on the electron transition characteristic of the composite but effectively introduced midgap states. The results demonstrated that adatom/graphene/titania hybrid composite would exhibit excellent potential for photocatalytic application.

The Liquid-Solid Phase Transition Characteristic and Protein Binding Property of Composite Cryogel with Embedded Cellulose Beads

Poly (hydroxyethyl methacrylate)-based composite cryogel with embedded macroporous cellulose beads (pHEMA-CB cryogel) could be of interest as chromatographic medium for bioseparation applications. In this work, liquid-solid phase transition characteristic of the suspension mixture containing HEMA, poly (ethylene glycol) diacrylate (PEGDA), ammonium persulfate (APS),N,N,N',N'-tetramethylethylenediamine (TEMED) and cellulose beads for the production of pHEMA-CB composite cryogel was investigated to reveal the solvent crystallization process occurring in the column. Freezing curves were obtained and the values of initial solvent crystallization temperatureTcand the freezing point temperatureTmcwere estimated. Protein binding property of the pHEMA-CB cryogel grafted with (vinylbenzyl) trimethylammonium chloride (VBTAC) was measured and discussed.

CROSSOVER FROM CHIRAL SUSCEPTIBILITY IN QED3

In the framework of truncated Dyson–Schwinger equation for fermion propagator, we investigate the chiral susceptibility with the rise of temperature in QED3, while it demonstrates a phase transition characteristic in the chiral limit and illustrates a crossover beyond chiral limit in this Abelian system.