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Measurement of permitivity and dissipation factor of water
Zimáková, Jana ; Zatloukal, Miroslav (referee) ; Špinka, Jiří (advisor)
This master `s thesis deals about the dielectric properties of water. It describes the basic chemical and physical properties of water and its distribution in terms of structure. It also describes the basic parameters of distilled water, deionized and superclean. In the chapter number 5 described the behavior of dielectrics in an electric field, determining the dipole moment by Claus-Mossotti 'equation, measurement of permittivity and loss factor. Practical part is consists of the design of the electrode systém, of measuring the water quality and evaluation of measured data
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Set possible causes for capacity loss of capacitors
Fabiánek, Marcel ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This thesis deals with formation of defects on through-hole capacitors. Process of wave soldering and its steps are described in the first part. The listing and description of possilble defects caused by wave soldering is followed after the first part. There are several sources of potential causes of capacity loss and a separate chapter to these causes. The last part contains a proposal of testing individual potencional causes. Their purpose is to reveal the root causes of formation of the defects and then the practical solution is described.
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IoT Manual Soldering Station and Technology Aspects
Němec, Ivo ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This thesis explores the Internet of Things, its applicability in soldering stations and its possible benefits in terms of quality control of the manual soldering process. The thesis summarizes the basic description of IoT, its historical development, possible threats and today's implementation in various devices. Furthermore, the principle of soldering stations and the IoT features implemented in them are described. Last but not least, possible benefits of IoT applicability in soldering stations are presented, such as services to make the manual soldering process more traceable and controllable.
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Electrical properties of the skin
Hellová, Miriam ; Čudek, Pavel (referee) ; Špinka, Jiří (advisor)
This work deals with the electrical properties of human skin, the possibilities of measuring its impedance, and the design of suitable electrodes for measurement. Various equivalent circuits for human skin were used, and phenomena that occur at the wet electrode-electrolyte interface, which significantly affect the measurement, were described. A description of the function of a dry planar electrode and its design for verification measurements were performed. Control measurements were performed using a EVAL-AD5933EBZ development kit in a frequency range of 5 kHz to 100 kHz at three different locations on the human body; the results were plotted in the form of the absolute value of the impedance and its phase. The accuracy of the measured values was verified by comparing the results with other works using a different electrode type. The main result of this work was to verify the possibility of using the geometry of a dry planar electrode in combination with an easily accessible evaluation board for simple diagnostic applications.
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Dielectric Elastomers
Fiala, Vojtěch ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
The thesis contains extensive theoretical information and consist of several parts, where in the first part of the text are specified mainly general knowledges about electroactive polymers (EAP) and their different types. In this part, the reader should get a basic view of the issues and realize sense of these materials. The following text is more specifically addressed on one group of electrical EAPs called dielectric elastomers (DE). Introduction to DE is conceived comprehensively, that means from general information and principles of function to specific and deeper information. For example in the text are included information about individual materials and differences between them, particular application areas, etc. Above all, the text focuses on the fields of sensorics and energy generation.
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Manual Soldering Station - Evaluation of Selected Parameters
Němec, Ivo ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This semestral work deals with the investigation of different principles of heating elements control in soldering stations and the influence of lead-free solder alloy on the life of soldering tips. The thesis summarizes the description of the sub-elements of the soldering stations and explains their functions. The defects of the soldering tips due to the use of lead-free solder alloys are also described. Last but not least, European directives governing the use of lead-free solder alloys in electronic and electrical products are mentioned.
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Test Equipment for Solder Joint Strength Measuring
Čechák, Ondřej ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This master thesis introduces the problematics of the tensile strength of soldered joints and the correlative mathematical formulas and the use of mentioned problematics in the technology of die shear/pull machines designed for the solder joint tensile strength measurement. It explains the importance and reasons for the use of this technology. The emphasis is then laid on the design and construction innovations of the current laboratory manual shear/pull measuring machine, its semi-automation and the possibility of utilizing the innovated system in a laboratory class of a subject on FEEC BUT.
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SnBi Solder Paste and Influence of Reactive Nanoparticles
Rychlý, Ivo ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This work deals with effects of nanoparticles, mainly copper and silver, on properities of lead-free solder pastes. It describes basic tests done on solder pastes according to IPC-TM-650 standards. In practical section this work focuses on the preparation of Sn-Bi solder paste and the measuring of viscosity. After that different concentrations of silver copper alloy nanoparticles are added to the SnBi solder paste. These solder pastes are tested by the IPC standarts and mechanical and resistive tests are done on printed circuit boards where the effects of mixed in nanoparticles are observed.
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