Selection of Parameters of Current Collection Systems of Turbo-Generators to be Monitored by Means of Technical Diagnostics

In this article the choice of parameters of the current collection systems is substantiates, which must be monitored by technical means. It is shown that such parameters are the intensity of the sparking under brushes, uniformity of current distribution on parallel brushes, vibrations and runout slip rings and the state of their surface. For monitoring these parameters Ecotech Ltd (Pskov) develops a hardware-software complex. Complex consists of the following devices: - device to monitor the intensity of sparking, - device for measuring the current of brushes, - device for measuring vibrations and runout, - device for exploring the surface of rotating slip rings. Development of hardware-software complex is supported by the Foundation for Assistance to Small Innovative Enterprises in the scientific and technical field

A Case Study on Investigation of Component Age Dependent Reliability Models - EC JRC Network on Use of Probabilistic Safety Assessments (PSA) for Evaluation of Aging Effects to the Safety of Energy Facilities - Task 4

The report presents the results of a case study on "Investigation of component age dependent reliability models" implemented by INPE and JRC IE in the frame of EC JRC Ageing PSA Network Task 4 activities. Several cases of Generalized Linear Model were proposed and investigated for the cases of continues and discrete data. The Fisher Chi-2 minimization approach was applied for goodness of fit test and parameters elaboration. Finally, uncertainty analysis was done for estimated parameters and model extrapolations. The results were analyzed and compared with other approaches.JRC.F.4-Nuclear design safet

Compressed sensing quantum process tomography for superconducting quantum gates

We apply the method of compressed sensing (CS) quantum process tomography (QPT) to characterize quantum gates based on superconducting Xmon and phase qubits. Using experimental data for a two-qubit controlled-Z gate, we obtain an estimate for the process matrix $\chi$ with reasonably high fidelity compared to full QPT, but using a significantly reduced set of initial states and measurement configurations. We show that the CS method still works when the amount of used data is so small that the standard QPT would have an underdetermined system of equations. We also apply the CS method to the analysis of the three-qubit Toffoli gate with numerically added noise, and similarly show that the method works well for a substantially reduced set of data. For the CS calculations we use two different bases in which the process matrix $\chi$ is approximately sparse, and show that the resulting estimates of the process matrices match each ther with reasonably high fidelity. For both two-qubit and three-qubit gates, we characterize the quantum process by not only its process matrix and fidelity, but also by the corresponding standard deviation, defined via variation of the state fidelity for different initial states.Comment: 16 pages, 11 figure

Optimizing OpenGL programs

У статті проаналізовано напрями оптимізації програм OpenGL через використання атласів. Розглянуто роль взаємодії та рендерингу об’єктів.The article analyzes the directions for optimizing OpenGL programs through the use of atlases. The role of interaction and rendering of objects is considered

The Comparison of Direct and Indirect Methods for Determining the Magnetocaloric Parameters in the Heusler Alloy Ni50Mn34.8In14.2B

The magnetocaloric properties of the Ni50Mn34.8In14.2B Heusler alloy have been studied by direct measurements of the adiabatic temperature change (ΔTAD(T,H)) and indirectly by magnetization (M(T,H)), differential scanning calorimetry, and specific heat (C(T,H)) measurements. The presence of a first-order ferromagnetic-paramagnetic transition has been detected for Ni50Mn34.8In14.2B at 320 K. The magnetocaloric parameters, i.e., the magnetic entropy change (ΔSM = (2.9-3.2) J/kgK) and the adiabatic temperature change (ΔTAD = (1.3-1.52) K), have been evaluated for ΔH = 1.8 T from CP(T,H) and M(T,H) data and from direct ΔTAD(T,H) measurements. The extracted magnetocaloric parameters are comparable to those of Gd

Giant field-induced adiabatic temperature changes in In-based off-stoichiometric Heusler alloys

Direct measurements of the adiabatic temperature change (ΔTAD) of Ni50Mn35In14.5B0.5 have been done using an adiabatic magnetocalorimeter in a temperature range of 250-350 K, and with magnetic field changes up to ΔH = 1.8 T. The initial susceptibility in the low magnetic field region drastically increases with temperature starting at about 300 K. Magnetocaloric effects parameters, adiabatic temperature changes, and magnetic entropy changes were found to be a linear function of H2/3 in the vicinity of the second order transitions (SOT), whereas the first order transitions do not obey the H2/3 law due to the discontinuity of the transition. The relative cooling power based on the adiabatic temperature change for a magnetic field change of 1.8 T has been estimated. Maximum values of ΔTAD = −2.6 K and 1.7 K were observed at the magnetostructural transition (MST) and SOT for ΔH = 1.8 T, respectively. The observed ΔTAD at the MST exceeds the ΔTAD for Ni50Mn35In14X with X = In, Al, and Ge by more than 20% and is larger than the Gd based Heusler alloys