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Textile SIW Rectangular Ring-slot Antennas for Off-body Communication
Vašina, Petr
In this paper, a textile SIW rectangular ring-slot antenna for the ISM frequency band 5.8 GHz is proposed. The antenna radiates a linearly polarized wave with the maximum radiation in the perpendicular direction to the antenna plane. The antenna is fabricated on the soft-shell fabric in the two versions. In the first version, the conductive layers were fabricated by a self-adhesive copper foil. In the second version, the conductive layers were fabricated by the screen printing on a foil ironed on the soft-shell fabric. Experimental results prove that the proposed antenna fabricated by copper foil achieves the impedance bandwidth of 3.1 % for the reflection coefficient less than -10 dB and the gain of 6.91 dBi. While screen printing antenna achieves the impedance bandwidth of 2.93 % for the reflection coefficient less than -10 dB and the gain of 7 dBi, respectively.
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The conductive layers in LTCC
Poledník, Tomáš ; Psota, Boleslav (referee) ; Kosina, Petr (advisor)
The bachelor thesis was focused on a determination of the limits of screen printing and on estabilishing a power loading of layers on LTCC. It describes the print of the conductive themes via the screen-printing method on the substrata. The thesis contains the description of a measuring on the conductive layers, and a processing its results. It was also performed the printing of layers on a corundum ceramics in order to compare the results. From the measured values were formed the graphs, which represent the possibility of the power loading of layers depending on the temperature and on the width of the thick-layer guide.
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Printed insulating interlayrs
Olejníková, Marie ; Zmeškal, Oldřich (referee) ; Dzik, Petr (advisor)
This bachelor thesis deals with preparation and study of printed insulating interlayers based on barium titanate. The composition of ink formulation and method of deposition were investigated. The composition was optimised with the type of added binder. The printing was made using a screen printing method. Characterisation of prepared layers was made using contact profilometry and optical microscopy. Dielectric properties of layers were subsequently analysed using the impedance spektroskopy method.
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Circularly polarized antenna integrated into 3D knitted fabric
Drápal, Ladislav ; Kadlec, Petr (referee) ; Raida, Zbyněk (advisor)
The thesis deals with the circularly polarized planar antenna with a working frequency of 5.8 GHz, which was published in [1]. For the antenna, a numerical model in ANSYS HFSS was created to verify the correctness of published parameters. The antenna [1] is of a relatively complicated geometry. In order to demonstrate sense of this geometry, a numerical model of a circularly polarized patch antenna with a working frequency of 5.8 GHz [2] was created. Simulated parameters of both the circularly polarized antennas were mutually compared. The antenna [1] was shown to exhibit a better directivity and a higher gain in the main lobe direction. Both the antennas were then optimized for the 2.4 GHz operation band and a textile substrate. Simulations showed that the patch antenna exhibits on a lower frequency and a textile substrate a higher gain and a better directivity. Both the antennas were manufactured by using a copper foil. The circularly polarized planar antenna [1] was additionally manufactured by screen printing to achieve better parameters. Measurement showed that the best parameters reach the patch antenna [2]. Planar antennas [1] in the 2.4 GHz frequency band did not meet the expectations by the size and complexity on the textile substrate.
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Microelectrode arrays for mioelectronic
Bráblíková, Aneta ; Vala, Martin (referee) ; Salyk, Ota (advisor)
Organic electronic biosensors are developed as suitable devices that can transform electrochemical processes within the cell membrane into an electronic signal and enable to measure electrical activity of excitable cells and tissues both in vitro and in vivo and thus represent valuable alternative to current cell monitoring methods. In this work we focus on the fabrication of electrophysiological sensors based on organic semiconductors printed by the material printing method. Microelectrode arrays (MEAs) are active components of the device, which can monitore cellular activity and above that stimulating cells with electrical pulses. The proposed platform should be used for cytotoxicity of potential drugs especially on cardiac cells (cardiomyocytes). The experimental part focus on specific production processes of platforms, which were prepared in the laboraty with emphasis on biocompatibility and conductivity of device.
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The influence of a pre-print thick layer paste viscosity on forming of layer
Ondráček, Michal ; Švecová, Olga (referee) ; Klíma, Martin (advisor)
This bachelor thesis deals with the theory of thick film technology and applying these layers. The work also includes basics of liquid rheology, methods of measurement viscosity and ways of mixing liquids. The main aim is to determine the influence of viscosity of thick film pastes for printing quality of the test structure using screen printing, in particular its flatness and sharpness. The aim is also measure the dependence of viscosity thick film pastes on mixing time.
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Optimalization of printing methods of organic semiconducting layers preparation
Ehlich, Jiří ; Vala, Martin (referee) ; Salyk, Ota (advisor)
Electrophysiological biosensors enables a novel way to measure electrical activity of biological structures both in-vitro and in-vivo and represents valuable alternative to current cellular activity measuring methods. Within this work we will be focusing on development of organic semiconductor (PEDOT:PSS) based Organic Electrochemical Transistors (OECTs) and optimization of material printing methods used in their development. These transistors are meant to be able to transfer electrochemical signals within the cell membrane to electrical signal. Such sensors should be used for cytotoxicity testing of chemicals and potential drugs on cardiomyocytes. Main benefits of OECTs are in their higher sensitivity thanks to their ability to locally amplify electric signals, better noise-signal ratio and outstanding biocompatibility. Their development is undemanding and inexpensive due material printing methods and materials processable at room temperatures.
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Printed Biosensor Based on Organic Electrochemical Transistor
Omasta, Lukáš ; Mikula, Milan (referee) ; Boušek, Jaroslav (referee) ; Salyk, Ota (advisor)
Organické elektronické zariadenia sú vyvíjané ako vhodné riešenia senzorov pre bioelektroniku, a to najmä kvôli dobrej biokompatibilite organických polovodičov v nich použitých. Takzvané biosenzory dokážu premeniť elektrochemické procesy na elektronický signál. Matrica takýchto biosenzorov môže simultánne skenovať množstvo biologických vzoriek, alebo rôznych tkanív v živých systémoch. Aktívnou súčasťou zariadenia je organický elektrochemický tranzistor (OECT). V tejto práci je diskutovaný teoretický rámec fungovania takéhoto zariadenia, jeho elektrická charakterizácia, aplikácia v biosenzoroch na báze buniek, spôsoby výroby a aktuálnym stavom techniky v oblasti organickej elektroniky. Experimentálna časť obsahuje konkrétne výrobné postupy vývoja OECT zariadení, ktoré boli použité v našom laboratóriu. Hlavný dôraz sa kladie na schopnosť vyrobených zariadení detekovať reakciu a monitorovať stimuláciu elektrogenných buniek. Za týmto účelom boli vyvinuté matice mikroelektródových OECT zariadení založených na polovodivom polyméri PEDOT:PSS. Tieto boli vyrobené s využitím bežnými tlačiarenských techník (atramentová tlač a sieťotlač) spolu so štandardnými litografickými postupmi. Najnovšie nami vyvinuté zariadenia dosahujú najväčšieho zosílením signálu, g = 2,5 mS a časovú konštantu t = 0,15 s. Tieto zariadenia sú porovnateľné, často dokonca lepšie ako niektoré iné najmodernejšie a plne litograficky pripravené senzory.
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Hot plate with power regulation
Lacika, Marek ; Skácel, Josef (referee) ; Búran, Martin (advisor)
This thesis deals with issues of used hot plates and thick-film technology. The theoretical part of diploma thesis contains a theoretical analysis and description of corresponding technology and usage of materials. The practical part of the thesis focuses on the design of the resulting device, which forms design of the test and optimized hot element, the initial design of the device and the design of models for temperature simulations. Then follows description of the practical realization of the motifs and testing of the created thick-film structure on a ceramic substrate. In the last part are shown simulations of heat transfer in the proposed model of the device.
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Textile waveguide
Pelikán, Michal ; Schejbal, Vladimír (referee) ; Raida, Zbyněk (advisor)
Diploma thesis is focused on manufacturing process of waveguide filter. Thesis is divided to 8 chapters. There is summarized theory of possible execution of waveguide filter, used materials, their influence and risks during production. Then are described possible steps of realization and necessary relations for its design, simulation and also practical realization. At conclusion are summarized, compared and described reached results.
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