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Low-labour demanding technological procedure of monitoring of stored product beetles using traps with multi-component attractant
Stejskal, Václav ; Aulický, Radek
The aim of the work was to provide pest control, agricultural and food industry practice with information about multi-component monitoring tool for stored product pest beetles. It was evaluated the laboratory efficacy of a new trap „Multi-Insect-Trap“, containing combined pheromone and food attractant for several storage pests species. In small arenas (exposure: 74 hours, 25oC) was tested 6 species of stored product beetles. The efficacy decreased in the following order: Cryptolestes ferrugineus – 100%, Lasioderma serricorne – 100%, Oryzaephilus surinamensis - 70%, Stegobium paniceum - 70%, Sitophilus granarius – 60% and Tribolium castaneum- 40%. The work was supported by projects of Czech ministry of agriculture NAZV QH91146 and Vyzkumný zamer 0002700604.
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Accurate wattmeter for measure power loss in feromagnetic controlled AVR
Smutný, Martin ; Drexler, Petr (referee) ; Roubal, Zdeněk (advisor)
Electronic wattmeters excel in very small (up to negligible) own consumption. The basiccomponents of these devices is the multiplier - a circuit whose output voltage is proportional to the product of input voltage. Wattmeter is a device that contains two coils, one of which is the current coil voltage and the second coil. Current coil is connected in series with the measured electrical circuit and the voltage measuredparallel to the coil circuit. Current flowing through the coil current causes a magnetic field is proportional to the current flowing through the phase shift and. Electromagnetic fields of both coils influence each other in case of measurements in a DC circuit, the resultingdeflection proportional to both voltage and current. When measured in AC electrical powercircuits can be determined using the effective values of current and voltage, and their mutualphase shift. A magnetic induction B can be determined using mean values. An analog multiplier are circuits, that are realized multiplication of two analog signals. They can be made by suitable connection (according to function) discreet parts. Nowadays there are integrated circuits in advance function, whose internal structure is made by complex of circuits with operating ampfliers and other circuits. These circuits have a very high accuracy of arithmetic operation which is mostly better than 1%. The analog multiplier are used in situation, when we need realize multiplication, division, exponentation, square root extraction and logarithmic calculation of analog signals.
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Evaluation of thermo-visco-elastic properties of FKM rubber at shear loading
Janoušek, Jaromír ; Svoboda, Jaroslav ; Pešek, Luděk
In this contribution results of experimental works aimed at the temperature influence on dynamic behaviour of rubber segments VITON (FKM) are summarized, especially the determination of elastomer modulus and loss factor. Two specimens were loaded by static prestress in the normal direction and follow-up track control in the slide. The expression of pressure force was determined. The realized method allowed to reach the pressure force on screws about 20 kN. The course of pressure force and warming of specimen were monitored and evaluated. The processing method was modify for exciting frequency. The visco-elastic parameters were evaluated from measure time course of exciting, response and inner temperature.
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Upbringing of the suckling in the family
BÖHM, Jan
In this study I wanted to put together my imaginations and how the upbringing and evolution of the suckling in the family should look like. On that base the parents should be able to give many stimulations to their child for his healthy evolution. This program should be acceptable to a wide spectrum of the parents universally with a view to time, money and local conditions. In my study I describe the upbringing of the suckling in the family with a view to his optimum evolution based on physical, mental and spiritual health. The first, theoretical part contains knowledge and experience of well-known Czech and foreign specialists who are engaged in those problems. The second, experimental parts brings the pieces of information about the right influence of the child´s upbringings and his gearing to programs of physical and mental evolution and his next life in the family with special care and as follows his putting across the social life. In statistical evaluating I compare all the results which are important for the right evolution of the child. My study wants to show important methods how to bring up the suckling from his first day of being born because it is the main meaning for his future life. At the beginning of each upbringing phase of the suckling it is acceptable to recommend this program to all the parents and it is possible to consult the methods of programs with specialists until they gain control of it themselves.
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Self-concept and sociometrical position in children with learning disabilities
NOVOTNÁ, Lenka
Target od the thesis is to explore the area of social consequences of specific learning disabilities. Specific learning disabilities have undoubtedly impact on academic performance and overall results in the context of school education. Their influence is much wider and we can say that it provides individuals with a specific learning disabilities a negative personal and social consequences. I established the following two hypotheses: I suppose that a group of children with specific learning disabilities will be marked selfconcept lower compared to the control group. I suppose that a group of children with specific learning disabilities will be marked by impaired sociometric position in the classroom compared to the control group. In the theoretical part of the thesis is contained explanations of basic concepts related to learning disabilities. Individual chapters are devoted to specific disorders in general and specifically dyslexia, its causes, incidence, manifestations, and reeducation. The other specific learning disabilities are mentioned in addition to dyslexia. In the second half of the theoretical section, I focus on pupil with dyslexia and his subjective complaints, parents and teachers of pupil with dyslexia, and the consequences of school failure and dyslexia on the individual's life. Practical part of the thesis processes with the research conducted among 24 elementary school students. Research using a variety of test methods for evaluating the impacts and consequences of specific learning disabilities on student self-concept and sociometric position in the classroom. Above 24 pupils were divided into two groups - experimental and control groups, which are compared among themselves.
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Preparation of nanoforms of layered piezoelectric of systems BI2O3-TA(2)O(5)-AO (A=CA,SR,BA)
Štarman, S. ; Matz, V. ; Kváča, Z. ; Mohyla, M. ; Olšák, V. ; Plocek, Jiří ; Vaněk, Přemysl ; Tylš, B.
Based on the known Aurivillius phases types ABi2Ta2O9 and A2BiTaO6 ( A=Ca, Sr, Ba) were supplemented with new compositions of layered tantalates, which resulted the possibility of the existence of a new phase Sr2BiTaO6. Ternary compounds with piezoelectric structure were prepared as nanoforms by solgel reactions of homogeneous acetate Bi, Ta, A and subsequent annealing in a controlled atmosphere. Annealing temperature was determined from DSC curves based on the weight loss and phase transitions. Composition and structure of nanocrystals has been analyzed by X-ray diffraction (XRD), scanning nanomorphology (SEM) and acoustic measurements.
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Compressive Creep Tests of An Aluminium Powder Composite Reinforced by Ceramic Particles
Dvořák, Jiří ; Král, Petr ; Balog, M. ; Simančík, F. ; Sklenička, Václav
The aim of this work is to study of a composite mixture of aluminium powders, to analyze of composite microstructure and mostly to describe the creep behaviour of composite in compression. The experimental material was based on Al powder matrix (Al 99%) about the particle size of less than 200 µm. This powder was mixtured with silicon carbide particles (SiC) having the size about 10 µm. The Al composite powder was prepared via conventional direct hot-extrusion (DE) at temperature 450°C. The microstructural investigations were performed using OM and SEM. It was found that DE process exhibits some breaking of carbide particles to size of range from 0.5 to 5 µm. Creep tests in compression were conducted at temperatures 423 -623 K and at applied stresses in the range from 60 to 100 MPa. Consequently, for an evaluation of controlling creep mechanisms an activation energy of creep and the stress exponent of the creep rate were determined.
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Počáteční chování bubliny páry v přehřáté kapalině
Vejražka, Jiří
The model is based on a simplified law for heat transfer of a growing and moving bubble and on solving the forces acting on this bubble. The model is represented by a system of ordinary differential equations and can be used until the time when bubbles start to wobble. An partially successful (but not convincing) attempt to validate this model by comparison with available experimental data was done. In most cases, the bubble behavior is controlled by a balance of the buoyancy with the added-mass force. In this aspect, the bubble behavior differs considerably from the case of constant-volume bubbles, for which the added-mass force is usually negligible. For the case of spherical bubbles, a simple analytical solutions are provided.
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Inteligent Controller of Active Magnetic Bearing
Turek, Milan ; Čech, Vladimír (referee) ; Ondrůšek, Čestmír (referee) ; Březina, Tomáš (advisor)
The PhD thesis describes control design of active magnetic bearing. Active magnetic bearing is nonlinear unstable system. This means it is not possible to use classic methods of control design for linear time invariant systems. Also methods of nonlinear control design are not universal and theirs application is not easy task. The thesis describes usage of simple nonlinear compensation which linearizes response of active magnetic bearing and allows usage of classic methods of control design for linear time invariant systems. It is shown that CARLA method can significantly improve parameters of designed controller. First part of thesis describes derivation of model of controlled active magnetic bearing and nonlinear compensation which linearizes response of controlled active magnetic bearing on input signal. Following part contains description of methods of state control design methods, selected methods of robust control design and most common methods of artificial intelligence used for control design and implementation. Next part describes hardware of used experimental device and its parameters. It also contains experimental derivation of model of electromagnetic force because the parameters are not available from manufacturer. Last part describes control design of active magnetic bearing. Several different approaches are described here. The approaches vary from completely experimental approach, through using Ziegler-Nichols method, state control design to methods for robust control design. During design is heavily used CARLA method which is very suitable for usage for online learning in real controller due its principle.
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Study of Electronic Control and Real Behavior in Variable Filtering and Oscillating Applications of Modern Active Elements
Šotner, Roman ; Ondráček, Oldřich (referee) ; Martínek,, Pravoslav (referee) ; Petržela, Jiří (advisor)
The thesis deals with electronically adjustable and configurable applications of the modern active elements. In the field there were presented various active elements in applications of the analog filters and oscillators which stem from basic and more or less similar principles of circuit synthesis and design. However, there is not provided study of real behavior in detail and in most cases electronic control of the various parameters in application is not verified. In the precise design of application is very important to identify problematic features and determine how much it influences functionality of the device. In this work several filtering structures based on common and modified synthesis principles (integrator loops) are compared in the view of multifunctionality, configurability, variability, kind of used electronic control and impact of influences of real elements on behavior. There are used standard methods like adjusting of variable transconductance, intrinsic value of current input resistance and not so common method based on variable current gain in design of modified and improved multifunctional filtering circuits. The last method of mentioned control enabled to find quite unique filter which allows continuous electronic change of transfer from band-reject to all-pass filter of the 2nd order without reconnection. It is much simpler than previous and more common integrator loops. Larger part of this work is focused on electronically controllable oscillators mainly on quadrature types. There is presented several very simply and elementary realizations which require minimal number of active and passive elements. There are also slightly or more complicated solutions which remove some drawbacks of mentioned simpler variants. First of all there is given attention on study of real behavior which make obvious different problems with mutual dependence of oscillation condition and oscillation frequency, dependence of produced amplitudes (quadrature types) on parameter which is controlling oscillation frequency, influence of this parameter on oscillation condition, etc. In the framework of this part of the thesis there was introduced a novel modification of current conveyor transconductance amplifier (CCTA) so called current-gain-controlled current conveyor transconductance amplifier (CGCCCTA). Requirements for novel applications in the field of oscillators for newly developed controllable current amplifier and digitally controllable current amplifier (DACA) at the Department of Telecommunication FEEC BUT lead to creation of several chapters of this work where mentioned active elements can be used. The important contribution of this work (for practical approach) is also experimental testing of most of designed circuits and determination of exact design equations and rules which take into account real behavior of circuits and confirm results obtained from experiments.
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