Quantitative Algebras and a Classification of Metric Monads

Quantitative algebras are $\Sigma$-algebras acting on metric spaces, where operations are nonexpanding. We prove that for finitary signatures $\Sigma$ there is a bijective correspondence between varieties of quantitative algebras and strongly finitary monads on the category $\mathsf{Met}$ of metric spaces. For uncountable cardinals $\lambda$ there is an analogous bijection between varieties of $\lambda$-ary quantitative algebras and strongly $\lambda$-accessible monads. Moreover, we present a bijective correspondence between $\lambda$-varieties of $\Sigma$-algebras as introduced by Mardare, Panangaden and Plotkin and enriched, surjections-preserving $\lambda$-accesible monads on $\mathsf{Met}$. Finally, a bijective correspondence between generalized $\lambda$-ary varieties and enriched $\lambda$-accessible monads on $\mathsf{Met}$ in general is presented

Low-Voltage Circuit-Breaker Behavior under Overload Conditions

This article deals with temperature-rise of current path of modern low-voltage circuit-breaker with rotary contact system at overloads and subsequent experimental verification of selected model. The first part describes optimal setting of input conditions of simulation and mainly transient phenomena at contacts causing dynamic change of contact resistances due to change of total contact force, a new challenge to be solved in this contribution. The second part devotes laboratory measurement on prepared sample of the breaker for verification of transient simulation. These simulations are not only important for understanding of rotary system behavior under overloads, but forms an essential part of R & D process due to the speed-up of optimal current path design. In the end, both the financial costs and time effort could be decreased

Physical and Numerical Difficulties in Computer Modelling of Pellet-Cladding Contact Problems for Burned-Up Fuel

The importance of fuel reliability is growing due to the deregulated electricity market and the demands on operability and availability to the electricity grid of nuclear units. Under these conditions of fuel exploitation, the problems of PCMI (Pellet-Cladding Mechanical Interaction) are very important from the point of view of fuel rod integrity and reliability. Severe loading is thermophysically and mechanically expressed as a greater probability of cladding failure especially during power maneuvering. We have to be able to make a realistic prediction of safety margins, which is very difficult by using computer simulation methods. NRI (Nuclear Research Institute) has recently been engaged in developing 2D and 3D FEM (Finite Element Method) based models dealing with this problem. The latest effort in this field has been to validate 2D r-z models developed in the COSMOS/M system against calculations using the FEMAXI-V code. This paper presents a preliminary comparison between classical FEM based integral code calculations and new models that are still under development. The problem has not been definitely solved. The presented data is of a preliminary nature, and several difficult problems remain to be solved.

Diagnostics of Various Phenomena in LV Devices Under Real Switching Conditions

The article deals with issues to be tackled when performing experiments with low voltage devices under real switching conditions and subsequently discusses various phenomena in an experimental device. The first part describes optimum setting of diagnostic equipment - mainly for optical diagnostic methods. The second part describes some phenomena encountered during switching process under real switching conditions - arc roots movement (cathode and anode spots). These phenomena are not only important for experimental study itself but also form necessary input data for numerical models and their validation

Універсітэт. - № 11 (2114)

PERMON makes use of theoretical results in quadratic programming algorithms and domain decomposition methods. It is built on top of the PETSc framework for numerical computations. This paper describes its fundamental packages and shows their applications. We focus here on contact problems of mechanics decomposed by means of a FETI-type non-overlapping domain decomposition method. These problems lead to inequality constrained quadratic programming problems that can be solved by our PermonQP package.11510

Permutation Entropy and Signal Energy Increase the Accuracy of Neuropathic Change Detection in Needle EMG

Background and Objective. Needle electromyography can be used to detect the number of changes and morphological changes in motor unit potentials of patients with axonal neuropathy. General mathematical methods of pattern recognition and signal analysis were applied to recognize neuropathic changes. This study validates the possibility of extending and refining turns-amplitude analysis using permutation entropy and signal energy. Methods. In this study, we examined needle electromyography in 40 neuropathic individuals and 40 controls. The number of turns, amplitude between turns, signal energy, and “permutation entropy” were used as features for support vector machine classification. Results. The obtained results proved the superior classification performance of the combinations of all of the above-mentioned features compared to the combinations of fewer features. The lowest accuracy from the tested combinations of features had peak-ratio analysis. Conclusion. Using the combination of permutation entropy with signal energy, number of turns and mean amplitude in SVM classification can be used to refine the diagnosis of polyneuropathies examined by needle electromyography

Rotating Gliding Arc: Innovative Source for VOC Remediation

The large-scale plasma treatment of waste gas in industrial or municipal conditions requires high efficiency of plasma conversion process at high processing speed, i.e., large volumetric flow. The integration of the plasma unit into existing systems puts demands on the pipe-system compatibility and minimal pressure drop due to adoption of plasma processing step. These conditions are met at the innovative rotating electrode gliding arc plasma unit described in this article. The system consists of propeller-shaped high voltage electrode inside grounded metallic tube. The design of HV electrode eliminates the pressure drop inside the air system, contrary the plasma unit itself is capable of driving the waste gas at volumetric flow up to 300 m3/hr for 20 cm pipe diameter. In the article the first results on pilot study of waste air treatment will be given for selected volatile organic compounds together with basic characteristic of the plasma unit used

Predictive control of systems with fast dynamics using computational reduction based on feedback control information

Predictive control is a method, which is suitable for control of linear discrete dynamical systems. However, control of systems with fast dynamics could be problematic using predictive control. The calculation of a predictivecontrol algorithm can exceed the sampling period. This situation occurs in case with higher prediction horizons and many constraints on variables in the predictive control. In this contribution, an improving of the classical approach is presented. The reduction of the computational time is performed using an analysis of steady states in the control. The presented approach is based on utilization of information from the feedback control. Then this information is applied in the control algorithm. Finally, the classical method is compared to the presented modification using the time analyses. © Springer International Publishing Switzerland 2015

Thermal Plasma of Electric Arc Discharge Between Composite Cu-Cr Electrsodes: Optical Emission and Electrode Surface Interaction

This work deals with investigations of thermal plasma of electric arc discharge between sintered composite Cu-Cr electrodes, which can be used in electrical contacts of vacuum circuit breakers. Breaking arcs between composite Cu-Cr as well as single-component copper electrodes were used to study the electrical properties, plasma optical emission and electrodes surface modification behavior. In particular, the temporal evolution of plasma emission spectra of electric breaking arcs in air atmosphere was investigated by Optical Emission Spectroscopy (OES). Scanning Electron Microscopy (SEM) with Energy-dispersive X-ray Spectroscopy (EDXS) were applied to analyze the cross-section of working layer of electrodes surface modified by the heat flux from the discharge