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Influence of gama prime changes on the heat transport phenomena of a nickel super alloy

Defect and Diffusion Forum 2017年 379卷 1-11页

作者： Koštial, Pavel Jonšta, Petr Kopal, Ivan Jančíková, Zora Koštialová Špička, Ivo Kulová, Tatána Vlčková, Irena Department of Material Engineering Faculty of Metallurgy and Materials Engineering VŠB-Technical University of Ostrava Czech Republic Faculty of Mining and Geology VŠB Institute of Physics Technical University of Ostrava Czech Republic VÍtkovice Heavy Machinery a.s. Czech Republic Department of Automation and Computing in Metallurgy Faculty of Metallurgy and Materials Engineering VŠB-Technical University of Ostrava Czech Republic Faculty of Industrial Technologies in Puchov University of Alexander Dubček in Trenčín Slovakia RMTSC MATERIAL METALLURGICAL RESEARCH Ltd. Remote site Ostrava VÚHŽ a.s. Czech Republic

The paper deals with the influence of microstructural changes of the nickel superalloy (NiS) on heat transport changes in MAR-M247. The dissolving annealing within the temperature interval of 900 - 1240°C and cooling in water has been applied to enhance structural changes. It has been shown that the narrow connection between the γ' phase morphology changes, as well as values of density, thermal conductivity and specific heat capacity. In the dissolving annealing process, the γ' particles change in certain cycles from fine to rough and back to fine one. Obtained results of changes of thermal conductivity, density and specific heat capacity correlate with image analysis and electron microscopy observation. © 2017 Trans Tech Publications, Switzerland.

关键词： Thermal conductivity

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An analytical framework for the study of solid body cooling

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Defect and Diffusion Forum 2017年 370卷 1-18页

作者： Kopal, Ivan Koštial, Pavel Jančíková, Zora Valíček, Jan Harničárová, Marta Alexander Dubček University of Trenčín Faculty of Industrial Technologies Púchov Krasku 491/30 Púchov020 01 Slovakia Institute of Physics Faculty of Mining and Geology VŠB-Technical University of Ostrava 17 listopadu 15/2172 Ostrava708 33 Czech Republic Department of Automation and Computing in Metallurgy Faculty of Metallurgy and Materials Engineering VŠB-Technical University of Ostrava 17 listopadu 15/2172 Ostrava708 33 Czech Republic Institute of Clean Technologies for Mining and Utilization of Raw Materials for Energy Use Faculty of Mining and Geology VŠB-Technical University of Ostrava 17 listopadu 15/2172 Ostrava708 33 Czech Republic RMTVC Faculty of Metallurgy and Materials Engineering VŠB-Technical University of Ostrava 17 listopadu 15/2172 Ostrava708 33 Czech Republic

This paper aims to study the cooling of a solid body. An analytical analysis of a solid body cooling in different regimes is presented, such as a simple first order exponential model, a modified exponential model, a generalized exponential model and the so-called regular temperature regime. The analysis also includes the influence of the dynamically changing relaxation time and we also present the solution of the nonlinear heat equation.

关键词： Cooling

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Temperature dependence of thermal properties of thermoplastic polyurethane-based carbon nanocomposites

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AIP Conference Proceedings 2016年第1期1768卷

作者： Kopal Ivan Koštial Pavol Valíček Jan Harničárová Marta Jančíková Zora 1VŠB-TU Ostrava Faculty of Mining and Geology Institute of Physics 17. listopadu 15 708 33 Ostrava-Poruba Czech republic 2TnUAD of Trenčin Faculty of Industrial Technologies in Puchov Department of Numerical Methods and Computing Modelling I. Krasku 491/30 Slovakia 3VŠB-TU Ostrava Faculty of Metallurgy and Materials Engineering Department of Material Engineering 17. listopadu 15 708 33 Ostrava-Poruba Czech republic 4VŠB-TU Ostrava Institute of Clean Technologies for Mining and Utilization of Raw Materials for Energy Use 17. listopadu 15 708 33 Ostrava-Poruba Czech republic 5VŠB-TU Ostrava Faculty of Metallurgy and Materials Engineering RMTVC 17. listopadu 15 708 33 Ostrava-Poruba Czech republic 6VŠB-TU Ostrava Faculty of Metallurgy and Materials Engineering Department of Automation and Computing in Metallurgy 17. listopadu 15 708 33 Ostrava-Poruba Czech republic

The present work is focused on the analysis of the temperature dependence of thermophysical parameters of polymeric nanocomposites based on a thermoplastic polyurethane matrix filled with different amounts of single-walled carbon nanotubes of high purity. The temperature dependence of thermal conductivity, thermal diffusivity, and specific heat capacity were analysed in a wide temperature range. The regression models of experimental data showed a good agreement with physical models based on the quantum interpretation of thermal transport phenomena in the solid materials above the Debye temperature. The temperature dependences of all three investigated thermophysical parameters showed the secondary relaxation transition that occurred in all tested nanocomposite materials. Moreover, the first-order exponential model for the dependence of investigated thermophysical parameters on the amount of single-walled carbon nanotubes in the thermoplastic polyurethane matrix at standard temperature and pressure has been created.

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Crystallizer's desks surface diagnostics with usage of robotic system

Crystallizer's desks surface diagnostics with usage of robot...

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作者： David, J. Jančíkoyá, Z. Frischer, R. Vrožina, M. VSB-TU Ostrava Department of Automation and Computing in Metallurgy 17. LISTOPADU 15 708 33 Ostrava - PORUBA CZ Czech Republic

Discussed problems are solved in Arcelor Mittal Ostrava a.s. company. VSB-TU Ostrava has its share on this solution in the frame of grant project TIP. The project has several goals, which relate with primary cooling system area in CSCD (Continuous Steel Casting Device). One target is concerned about surface quality of crystallizer's desks, also from point of view of its quality *** terms of project solution was solved a crystallizer's desks defects catalogue and methodology of their evaluation. Also was made methodology for quality evaluation of narrow crystallizer's desks, which are dismantled in maintenance area. There were proposed a laser scanning of the crystallizer's desks surface with usage of Laser sensor. In cooperation with DASFOS CZ, s.r.o. was proposed new method of inner crystallizer's chamber measuring. In this paper are presented partial results of this solution, including first results from prototyped measuring device.

关键词： Quality control

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Alternative methods of power supply for autonomous intelligent wireless sensors

Alternative methods of power supply for autonomous intellige...

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International Carpathian Control Conference (ICCC)

作者： Miroslav Mahdal Renata Wagnerová Robert Frischer Department of Control Systems and Instrumentation VSB-Technical University of Ostrava Ostrava Czech Republic Department of Automation and Computing in Metallurgy VSB-Technical University of Ostrava Ostrava Czech Republic

An intelligent wireless smart sensors leak into many branches in technical diagnostics recently. Need of measurement a record various quantities is still rising. Main focus is aimed to energy saving houses, to large complex with many air conditioning units, to industry, where is need of simple action intervention on many places. Problem coming up, when the building has no sufficient cable infrastructure. Additional costs in many cases discourage from installation of modern smart sensors and action elements and an efficiency of current process can be decreased. The modern intelligent smart sensors working over the 802.15.4 protocol solves these disadvantages. Energy harvesting method perfectly fit for powering these autonomous smart sensors. Main advantage of this approach is lack of any wires. Data transmission is ensured wirelessly in non licensing band 2.4GHz and modern DC-DC converter take over power supply delivery. This converter is able to accept minimum input voltage in order of tens mV. Integration of these technologies is fully autonomous wireless smart sensors working in discontinuous operation without necessity to change or charge supply batteries. To working properly, only few degrees of thermal gradient is sufficient.

关键词： Wireless sensor networks Wireless communication Intelligent sensors Temperature measurement Temperature sensors Energy harvesting

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Design and Realization of Low Cost Discrete PSD Controller for Power Electronics Applications

Design and Realization of Low Cost Discrete PSD Controller f...

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International Conference on Computer Engineering and Applications (ICCEA)

作者： Ondrej Krejcar Michal Tutsch Robert Frischer Ivo Spicka Department of Measurement and Control Faculty of Electrical Engineering and Computer Science VSB-Technical University of Ostrava Ostrava Czech Republic Department of Automation and Computing in Metallurgy Faculty of Metallurgy and Materials Engineering Technical University of Ostrava Ostrava Czech Republic

ISBN: (纸本)9781424460793;9780769539829

Most systems are controlling by common PID controllers. These PID controllers are available in variety possibilities. They are divided by types of controlling systems, by speed of action interference, by complexity, by robustness etc. Most of industrial controllers are very expensive and except of some basic setting they are not offering any other way, how to involve into controlling process. On the other side, developing new analog controller to control simple systems is not reasonable in financial or time issue. That's why we decided to build simple, discrete controller and implement its algorithm into single chip eight bit microcontroller (MCU). This discrete controller - PSD - is characteristic its simplicity and variability. It can control plenty of less complicated systems by a mere change of its characteristic parameters. Thanks to modern approach is possible to create a full-featured controller including power action element on an area equal to 7cm 2 .

关键词： Costs Power electronics Control systems Three-term control Interference Robust control Electrical equipment industry Industrial control Process control Microcontrollers

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Continuous Noninvasive Blood Pressure Measurement by Near Infra Red CCD Camera and Pulse Transmit Time Systems

Continuous Noninvasive Blood Pressure Measurement by Near In...

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International Conference on Computer Engineering and Applications (ICCEA)

作者： Petr Zurek Ondrej Krejcar Marek Penhaker Martin Cerny Robert Frischer Department of Measurement and Control Faculty of Electrical Engineering and Computer Science VSB-Technical University of Ostrava Ostrava Czech Republic Department of Automation and Computing in Metallurgy Faculty of Metallurgy and Materials Engineering Technical University of Ostrava Ostrava Czech Republic

ISBN: (纸本)9781424460793;9780769539829

The need of continuous blood pressure measurement is usable in wide spectrum of applications from physicians practice to home care applications. Many types of blood pressure measurement devices can be bought in electronics shops. All such devices are contact measurement devices which need to be in contact of human body (hand or foot mainly). Secondary they allow only one measurement per several minutes interval (typically ones in 10 minutes). Our goal is to develop a small device for noninvasive continuous measurement of blood pressure. This device must be a small battery powered embedded system which measure a blood pressure during a long time period and send this information remotely to operator's stations. We would like to try two systems of blood pressure monitoring. The first one is system with NIR CCD camera (Near Infra Red), which measure the wide changes of the blood vessels and the second one is system, which measure the pulse transmit time (PTT). At the end we can compare the systems and get information, which system will be a right way to obtain exact continuous blood pressure information.

关键词： Pulse measurements Blood pressure Pressure measurement Time measurement Charge coupled devices Charge-coupled image sensors Biomedical monitoring Battery charge measurement Humans Foot

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Incremental PIC controller with handled limit states and manual settings

Incremental PIC controller with handled limit states and man...

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International Conference on Mechanical and Electronics Engineering (ICMEE)

作者： Ondrej Krejcar Ivo Spicka Robert Frischer Milan Heger Department of Measurement and Control Centre for Applied Cybernetics Technical University of Ostrava Ostrava Czech Republic Department of Automation and Computing in Metallurgy Technical University of Ostrava Ostrava Czech Republic

A proportional-integral-derivative controller (PID controller) is a basic control loop feedback controller widely used in industrial control systems. An “error” value as the difference between a measured output system variable and a desired setpoint is calculated. The controller role is to minimize the error by adjusting the system inputs. For best performance, the PID parameters must be tuned according to the controlled system parameters.

关键词： TV Pulse width modulation Switches Clocks Random access memory Noise Gold

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Simple Discrete Controller with PWM Power Output

Simple Discrete Controller with PWM Power Output

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ICONS International Conference on Systems

作者： Ondrej Krejcar Robert Frischer Ivo Spicka Department of Measurement and Control CAK FEECS VSB-Technical University of Ostrava Ostrava Czech Republic Department of Automation and Computing in Metallurgy VSB-Technical University of Ostrava Ostrava Czech Republic

One of problems of the most common used industrial controllers is in their very expensive price. Moreover, they not offer any other features except some basic ones, how to affect controlling process (e.g. settings of PWM (Pulse Wide Modulation) switching frequency). On the other side, developing of a new analog controller to control a simple system is not reasonable due to financial or time issues. That is the reason why we decided to build a simple, discrete controller and implement its algorithm into a single chip, eight bit microcontroller unit (MCU). Such a discrete PSD controller is characteristic for its simplicity and variability. It can control a plenty of less complicated systems by a simple change of its characteristic parameters. Thanks to modern approach it is possible to create a full-featured controller including power action element on a tiny area equal to 7 cm 2 .

关键词： Pulse width modulation Control systems Automatic control Proportional control Interference Process control Pi control Three-term control Power measurement automation

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Use of accelerometers for material inner defect detection

Use of accelerometers for material inner defect detection

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International Conference on Applied Electronics, AE

作者： Ondrej Krejcar Robert Frischer Department of Measurement and Control Center of Applied Cybernetics Faculty of Electrical Engineering and Computer Science VSB-Technical University of Ostrava Ostrava Czech Republic Department of Automation and Computing in Metallurgy VSB-Technical University of Ostrava Ostrava Czech Republic

This paper deals with a possibility of non-destructive diagnostics of solid objects by software analysis of vibration spectrum by accelerometers. By a use of MATLAB platform, a processing and information evaluation from accelerometer is possible. Accelerometer is placed on the measured object. The analog signal needs to be digitized by a special I/O device to be processed offline with FFT (Fast Fourier Transformation). The power spectrum is then examined by developed evaluating procedures.

关键词： Accelerometers Vibrations Software Conferences Distortion measurement Converters Unified modeling language

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