Identification and control for heart rate regulation during treadmill exercise

This paper proposes a novel integrated approach for the identification and control of Hammerstein systems to achieve desired heart rate profile tracking performance for an automated treadmill system. For the identification of Hammerstein systems, the pseudorandom binary sequence input is employed to decouple the identification of dynamic linear part from input nonlinearity. The powerful epsilon-insensitivity support vector regression method is adopted to obtain sparse representations of the inverse of static nonlinearity in order to obtain an approximate linear model of the Hammerstein system. An Hinfinity controller is designed for the approximated linear model to achieve robust tracking performance. This new approach is successfully applied to the design of a computer-controlled treadmill system for the regulation of heart rate during treadmill exercise. Minimizing deviations of heart rate from a preset profile is achieved by controlling the speed of the treadmill. Both conventional proportional-integral-derivative (PID) control and the proposed approaches have been employed for the controller design. The proposed algorithm achieves much better heart rate tracking performance.     

Minimax optimal control of uncertain systems with structured uncertainty

This paper considers a minimax control problem for an uncertain system containing structured uncertainties. The uncertainties in this system are assumed to satisfy a certain integral quadratic constraint. For a given initial condition, the minimax optimal controller is constructed by solving a parameter-dependent Riccati equation of the game type. This controller leads to a closed-loop uncertain system which is absolutely stable.     

The Kalman-Yakubovich Lemma for non-stationary systems and its applications

An existence problem for non-stationary Lyapunov functions is considered. This problem is connected according to a certain rule with the linear Hamiltonian system that is called adjoint. We apply this method to obtain conditions of absolute stability and adaptive stabilization for non-linear non-stationary systems.     

Recursive state estimation for uncertain systems with an integralquadratic constraint

This paper considers a robust state estimation problem for a class of uncertain systems where the noise and uncertainty are modeled deterministically via an integral quadratic constraint. The robust state estimation problem involves constructing the set of all possible states at the current time consistent with given output measurements and the integral quadratic constraint     

Pragmatic aspects of the solution of FMS scheduling problems using hybrid dynamical approach

Hybrid Dynamical (or Switched Server) approach is a relatively new direction in the solution of FMS scheduling problems. The theoretical results in this field are promising, but a number of questions should be cleared for practical applications.Some of these are: How to choose demand rates? How to provide the stability of processes in multi-machine group cases? What are the main characteristics of the processes and how to determine the suitable values of the parameters?In relation to the first two questions, proposals are given in the present paper. For demand rates determination, relations giving the upper and lower boundary values are proposed. For multi-machine group processing, the controlled buffer technique was developed. In relation to the others, simulation studies are proposed. Two of the simulation approaches are described in this paper and some demonstration is also given.The simulation results obtained from case studies show that the overlapping production obtained using the hybrid dynamical approach (HDA) are far more effective than batch processing. The decrease of production times may reach 20–30% or more.     

Materials based on highly concentrated ceramic binding suspensions (HCBS). Comparative evaluation of the properties and in-service durability of pocket blocks of intermediate ladles

The Pervouralsk Dinas Plant has developed a technology for and started industrial production of pocket blocks based on bauxite ceramoconcrete for intermediate ladles. The structure and service properties of the blocks are compared with corresponding imported parts. The structure of the imported blocks is characterized by the presence of large (process) pores and the material is impregnated in service, whereas the developed blocks possess a homogeneous fine-capillary structure and are not impregnated in service.     

3D environmental extremum seeking navigation of a nonholonomic mobile robot

A nonholonomic under-actuated robot with bounded control travels in a 3D region. A single sensor provides the value of an unknown scalar field at the current location of the robot. We present a new kinematic control paradigm to drive the robot to the maximizer of the field, which is different from conventionally trying to align the velocity vector with the field gradient. The proposed strategy does not employ gradient estimation and is non-demanding with respect to both computation and motion. Its mathematically rigorous analysis and justification are provided. Simulation results confirm the applicability and performance of the proposed guidance approach.     

Neutral beam dump with cathodic arc titanium gettering

An incomplete neutral beam capture can degrade the plasma performance in neutral beam driven plasma machines. The beam dumps mitigating the shine-through beam recycling must entrap and retain large particle loads while maintaining the beam-exposed surfaces clean of the residual impurities. The cathodic arc gettering, which provides high evaporation rate coupled with a fast time response, is a powerful and versatile technique for depositing clean getter films in vacuum. A compact neutral beam dump utilizing the titanium arc gettering was developed for a field-reversed configuration plasma sustained by 1 MW, 20-40 keV neutral hydrogen beams. The titanium evaporator features a new improved design. The beam dump is capable of handling large pulsed gas loads, has a high sorption capacity, and is robust and reliable. With the beam particle flux density of 5 × 10(17) H∕(cm(2) s) sustained for 3-10 ms, the beam recycling coefficient, defined as twice the ratio of the hydrogen molecular flux leaving the beam dump to the incident flux of high-energy neutral atoms, is ～0.7. The use of the beam dump allows us to significantly reduce the recycling of the shine-through neutral beam as well as to improve the vacuum conditions in the machine.     

Use of the focusing multi-slit ion optical system at RUssian Diagnostic Injector (RUDI)

The upgrade of the diagnostic neutral beam injector RUDI in 2010 was performed to increase the beam density at the focal plane in accordance with the requirements of charge-exchange recombination spectroscopy diagnostics. A new focusing ion-optical system (IOS) with slit beamlets and an enlarged aperture was optimized for 50% higher nominal beam current and reduced angular divergence with respect to the previous multi-aperture IOS version. The upgraded injector provides the beam current up to 3 A, the measured beam divergence in the direction along the slits is 0.35°. Additionally, the plasma generator was modified to extend the beam pulse to 8 s.     

Generation of high charge state metal ion beams by electron cyclotron resonance heating of vacuum arc plasma in cusp trap

A method for generating high charge state heavy metal ion beams based on high power microwave heating of vacuum arc plasma confined in a magnetic trap under electron cyclotron resonance conditions has been developed. A feature of the work described here is the use of a cusp magnetic field with inherent "minimum-B" structure as the confinement geometry, as opposed to a simple mirror device as we have reported on previously. The cusp configuration has been successfully used for microwave heating of gas discharge plasma and extraction from the plasma of highly charged, high current, gaseous ion beams. Now we use the trap for heavy metal ion beam generation. Two different approaches were used for injecting the vacuum arc metal plasma into the trap--axial injection from a miniature arc source located on-axis near the microwave window, and radial injection from sources mounted radially at the midplane of the trap. Here, we describe preliminary results of heating vacuum arc plasma in a cusp magnetic trap by pulsed (400 μs) high power (up to 100 kW) microwave radiation at 37.5 GHz for the generation of highly charged heavy metal ion beams.