Řada strojní. 2007, roč. 53 / Mechanical Series. 2007, vol. 53

Permanent URI for this collectionhttp://hdl.handle.net/10084/111972

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Now showing 1 - 20 out of 52 results

The use of artificial neural network for the improvement of quality of steelworks products
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Zimný, Ondřej
This contribution deals with the application of artificial neural networks in metallurgy. There were problems with the forging ingots made of carbon steelbrand grade in accordance with ČSN 11523 standard in the Czech Republic. The problems occurred randomly and independently from the technological procedure. The creation of the new artificial neural networks is based on the data provided by the steelworks company. The data were based on carbon steelbrand grade in accordance with ČSN 11523 standard in the Czech Republic. The new artificial neural network has been created by the computer programme STATISTICA – Neural Network. The artificial neural networks with the best results have been used to create the response graphs and sensitivity analysis. These response graphs represent the influence of the first element on the system. The results of this project indicate that the use of artificial neural networks for predicting defects of ingots in steelworks is very perspective.The problem was solved together with further applications of artificial intelligence in the framework of the grant project GAČR 106/05/2596.
Information and communication technology support successful application of process management in the company
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Wolf, Petr
The author describes the efficient connection of process management together with information and communication technology (below ICT) in the company in this paper. Only companies able to react to the real-world impulses of the volatile environment of the global market and whose management will be able to manage the company at the same time can become successful. Process management supported by well design ICT is the tool that is able to help in such conditions where it is impossible to reach the necessary improvement within the existing process conditions. The modern ICT is the part of the every reengineering effort. The author has the practical experiences with implementation of process management system.
Zigbee wireless modules with smart sensors
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Wojciaszyk, Petr
This paper deals with intelligent instrumentation in wireless networks. The significant parts are created tasks with the wireless technology. These tasks are formed with the Freescale ZigBee modules 13192-EVB or Microchip modules PICDEM Z. The 13192-EVB module includes RS232 and USB (FTDI chip) interface to connect with the PC, ZigBee chip MC13192 for wireless communication, 8-bit microcontroller MC9S08GT60 with A/D converters, switches and LEDs. Programmed additional subroutines are realized on evolutionary board Axiom AXM-0308 mounted with the Freescale MC9S08GB60 (HCS08). The PICDEM Z module includes RS232 interface to connect with the PC, the additional card with the wireless ZigBee chip CC2420, 8-bit microcontroller PIC18LF4620 with A/D converters, switches and LEDs.
Multicriterion modelless PID controller autotuning keeping desired values of control quality indicators
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Vrána, Stanislav; Šulc, Bohumil
The development of the autotuning method presented here was motivated by the demands of industrial practice. Industry prefers to use PID controllers and to make experimental settings on-line. Usually used tuning methods have two disadvantages: interruption or restriction of control function while the controller is being set and the use of Ziegler and Nichols rules, which leads to stable but oscillating responses. The paper describes one way of experimentally obtaining the control quality indicators based on frequency response evaluation and using them in a new optimal controller parameter setting computation procedure without control function interruption.
Controller tuning for integral plus time delay plants
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Vítečková, Miluše; Víteček, Antonín
This paper describes and compares PI and PID analog controllers tuning methods for integration processes with time delay. The integrating plants are frequently encountered in a process industry and their control is often problematic. The uses of the described tuning methods are shown in the example.
An orthogonal neural network for nonlinear function modelling
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Škutová, Jolana;
Neural networks provide one of the means for identification or control of a nonlinear system. Multilayer feedforward network is often used in those areas. Using this kind of neural network may result in premature termination of learning before the network weights reach a global minimum, a small training convergence, an unsuitable weight parameters initialize and the stability for on-line implementation. In this paper, an orthogonal neural networks (ONN) is presented. The ONN’s hidden layer consists of neurons with orthogonal activation function. The ONN have a much higher learning speed than the multilayered feedforward networks.
Remote administration of control systems
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Škuta, Jaromír
This contribution describes a possibility of implementation of external I/O units for real time control of laboratory models. DataLab I/O is used as external I/O unit. This unit includes digital and analog input/output. Control Web 5 components (pid_controler, boolean_controler) are used for control algorithm. These algorithms are applied at the first control layer in industrial PC DataLab PC/LCD. This application communicates with superior level using RS 485 bus. Second and third control level of control are realized by Control Web 2000 system. Access from the Internet is top level of control of this laboratory task.
User feedback on redesigned faculty webpage
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Smutný, Pavel
This contribution describes practical experience from conducting heuristic evaluation and web usability test of a new version of Faculty of Mechanical Engineering, VŠB-TUO Web site. Usability is a quality attribute that assesses how easily visitors can access and use Web sites. The goal of most usability testing is to uncover any problems that users may encounter so those problems can be fixed. Web usability test of the new version of the Faculty of Mechanical Engineering proved that most of the updated structure is clear to users and it has logically constructed information architecture.
Temperature measurement by contact smart sensors
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Smutný, Lubomír
The paper deals with actual state of intelligent temperature sensors. There are characterized standard principles and properties of contact smart temperature transducers with an accent on the new trends in this area. There are described even traditional principles of temperature sensors, further quick developing group of noncontact smart temperature sensors. Briefly there are characterized a knowledge and application experiences from this area obtaining on the Department of Control Systems & Instrumentation VŠB-TUO.
Control design for an MR damper in a driver's seat
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Sapiński, Bogdan
The paper is concerned with identification and control of the magnetorheological (MR) damper recommended for suspended seat applications. It is assumed that the damper force is given by formula proposed by Spencer and the model exhibits the functional dependence of the parameters on the input current. The identified model is applied in control design for an MR damper in a driver’s seat. It is shown that the performance of the feedback system is improved while compared to the open-loop system.
Cable vibration reduction using an attached MR damper
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Sapiński, Bogdan
The paper addresses vibration reduction of a cable with a transversely attached magnetorheological (MR) damper operating in passive and controlled modes. The model of the cable-MR damper system is presented. The control algorithm for MR damper based on optimal viscous damper emulation is described. Numerical data to demonstrate MR capabilities in cable vibration reduction are provided. The efficacy of an MR damper in reducing cable vibrations is confirmed experimentally.
Automated hydraulic device for CEC process engineering
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Pluta, Janusz
The paper presents a prototype automated hydraulic device for cyclic extrusion compression (CEC) process engineering. Presented device is a horizontal double hydraulic press equipped with electrohydraulic control system, designed using proportional technique and microprocessor control. A first part of this paper presents a structure and a working scheme of the device. A second part describes implemented device’s measurement and control circuit. Sample characteristics from extrusion process, recorded during press work, are presented in final part.
Control of the actuator with pneumatic artificial muscles in antagonistic connection
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Piteľ, Ján; Balara, Milan; Boržíková, Jana
The actuator based on pneumatic artificial muscles in antagonistic connection was designed and realized on the author’s workplace. The pneumatic artificial muscles are acting against themselves and resultant position of the actuator is given by equilibrium of their forces according to different pressures in muscles. The pressures in artificial muscles (and in this manner muscles contraction too) are controlled by four solenoid valves (two for muscles filling and two for emptying). On the theoretical and experimental basis the block diagram for position control of the actuator arm (with possible slave velocity control loop) was designed. The new algorithm based on simultaneous pressure control only in one muscle was designed too. This algorithm reduces requirements for control of such actuator.
Parameterization-based control of anisochronic systems using RMS ring
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Pekař, Libor
The contribution brings an engineering acceptable control design approach for so-called anisochronic systems. The method is based on algebraic tools in the ring of RQ-meromorphic functions and it was developed for a wide class of delayed systems. Anisochronic systems (models) include delays also in their dynamics and can be delayed in the conventional input-output sense as well. The control synthesis consists in the solution of the Bèzout identity and Youla-Kučera parameterization resulting in the Smith-like control structure. A final controller can be tuned by a suitable choice of a scalar real parameter. Among many others tuning methods, the equalization method is adopted. Anisochronic models and presented approach is suitable also for high order dynamics approximation and autotuning procedures. First order stable and unstable simulation examples are presented.
Logical control of the laboratory railways model
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Pavlas, Roman
The topic of this paper is focused on description of the laboratory railway model and its control system which is based on PLC automat. On introduction are described main parts of the railway model which is located in department’s laboratory (railway station, depot, works railway, storage track and sections of the railway). In first chapter are shortly described rules of the railway traffic (theory related to safety systems in railway). Also the safety system proposal for modelated railways is here (types of semaphores and their position in model). The second chapter describes tracking control system of this model (PLC system ABB line 800 and its components – central control unit, input/output units, communication units of industrial bus Profibus and power-supply unit) and the methods of its programming (with using of the PC computer and special development software ABB Control Builder). In the next are described algorithms for controlling of traffic on the railway model. In the last part, the possible evolutions of automatic systems are described here (proposal of manually controled panel which will use PLC, visualisation of the tracking traffic, possibilities to control by using of the digital coder/decoder systems etc.).
Optimal Ewma control chart design using selected statistical software
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Noskievičová, Darja
Today there are many statistical software packages wholly or partially specialized in statistical process control methods (SPC). They offer not only classical Shewhart control charts but also advanced methods suitable for non-standard situations when classical Shewhart methods fail. The ability to select the suitable control chart and insert data into the PC program is not sufficient for the effective and correct application of the selected control chart. The PC programs ask for some parameters whose optimal setting determinates correct application of the selected control chart. And information in Helps often is not sufficient. In this paper these problems are analyzed when designing optimal EWMA chart parameters using Statgraphics Plus, version 5.0.
Mathematical models of phenomena at gas blowing into ladle
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Morávka, Jan; Michalek, Karel
The paper describes the physical and cybernetic approach to the task of looking for an appropriate mathematical approximation-regression model of the measured standardised concentration of the tracer at a scale physical model of the casting ladle when blowing the steel by inert gas. The physical approach allows assembling an adequate mathematical model of the processes in the shape of a so-called white box, where the structure of the model are known. The cybernetic approach only draws on the measured inputs and outputs (so-called black box) as well as any additional conditions (so-called grey box) and the structure of the model is chosen according to them. These mathematical models are referred to as empirical models. The paper presents and compares four mathematical models – physically adequate one and three empirical ones.
Software Cosimir Professional - simulation, modelling and programming tool
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Mihalíková, Jana; Líška, Ondrej
Simulation is appropriate toll for effective assimilation system. We're been using programs from advice the COSIMIR®, i.e. the COSIMIR® PLC, the COSIMIR® Robotic and the COSIMIR® Professional. This program is lot software, which are using for simulation, projection, and programming and for virtual reality. COSIMIR® Professional is the industrially tried and tested, extremely high-performance development software for creating 3D simulation systems for automation technology. It combines three tools under one common interface 3D simulation, 3D modelling and robot programming.
A strongly stable implementation of state derivative feedback in system vibration suppression
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) McGahan, Paul; Vyhlídal, Tomáš
The effect of small delays in the state derivative feedback control loop is studied. Such an unusual feedback has proved useful in system vibration suppression, which is used here as a case study example. It is shown that even very small delays at the system inputs can destroy stability of the closed loop system. To prevent such fragility with respect to the delays, the strong stability concept developed for the neutral time delay systems is adopted. It is demonstrated that only such feedback gains can practically be used for which the closed loop system is strongly stable.
Control of model through Intranet/Internet network
(Vysoká škola báňská - Technická univerzita Ostrava, 2007) Mahdal, Miroslav
The laboratory model of tanks, structure and features are described in the paper. Programmable logic controller Mitsubishi FX is used for control of the whole model. Six new functions were programmed for PLC Mitsubishi including functions for operating. All functions were programmed in Melsec Medoc Plus program version 2.1. Human interface SCADA/HMI for visualization within InTouch program, which can be used for control of the system providing that relevant rights are set, was created for the model. Visualization and control of the model were designed and implemented not only within the local network but also through Internet with the help of the industrial information server SuiteVoyager that gathers data and transfers it to clients in the form of web pages. Actual and historical alarm messages are acquired from distributed alarm system of the InTouch application.

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