The aim of this work deals with the design and manufacture of a device for mixing of magnetic beads in solution by magnetic field. It is based on my previous bachelor thesis, where the device was created for one microtube (one sample). In this following work, the three improved variants for mixing and separation of 96 samples at one time were designed. The first variant of device, derived from functional prototype from bachelor thesis, was manufactured. First, the magnetic circuit and power converter were designed. Subsequently, the device was manufactured just for one microtube due to functionality testing. The third variant was realized only experimentally, the construction was designed in CAD program, and individual parts were created using 3D printer. As an alternative solution, which should be the compromise among electromagnetic and mechanical stirring, additional prototype was manufactured using 3D printer and CNC instrument. This prototype utilizes neodymium magnets and a stepper motor. The capability of magnetic beads mixing in solution was verified.

This master's thesis focuses on the utilization of an artificially created weak magnetic field for navigation in 3D space. The theoretical part of this work deals with the general properties of the magnetic field and with its description. The next section of the theoretical part contains an overview of measuring principles for magnetic field measurements. Based on various types of measuring principles, the thesis elaborates on commercially available miniature sensors for magnetic field measurement with a measuring range up to 10 mT. The work focuses mainly on the magnetoresistive principle and fluxgate sensors. Furthermore, the theoretical part contains descriptions of methods for modeling the magnetic field of simple permanent magnets and various magnet assemblies. Lastly, the theoretical part involves a patent search of devices used for locating magnets that are installed in an intramedullary nail, which is used in intramedullary stabilization used on fractures of human bones. By locating the magnet in the nail, it is possible to precisely determine the position of the mounting holes. The practical part of the thesis deals with the analysis of magnetic field behavior in the vicinity of various magnetic assemblies, which were modeled in COMSOL Multiphysics using the finite element method. The models were created with the aim of analysing the behaviour of the magnetic field in the vicinity of the magnets and at the same time to find possible analytical functions that could be used to determine the position of the magnet in space relative to the probe. The result of this work is an analysis of various assemblies, which contains graphs of different dependencies and prescription of polynomial functions that approximate these dependencies. Another part of the thesis is the design of a probe that serves to locate the magnetic target. The work describes two possible methods of localization. For the differential method, a user interface in LabVIEW was created. The probe based on this method is fully capable of locating the magnet in the 2D plane. The state space search method is described only in theory.

This thesis deals with the problem of practical application of FDTD technique for simulation of image formation in coherence controlled holographic microscope. Various ways for obtaining scattering matrices are explored in detail and the optimal technique based on a rigorous calculation of the far field is proposed. The scattering matrix, containing information about the observed sample, is subsequently used in analytic calculation of holographic signal; two levels of approximation of pupil function are also evaluated. The results are compared with a traditional approach based on Rytov approximation resulting in specification of the parameter domain where the approximation is applicable. Based on the simulations of the microscope, the dependence of axial resolution on apertures of the objective and the condenser and sensitivity of the signal to changes of refractive index of the sample is also studied.

V minul©m stolet­ byl vynaloen znaÄn vzkum na pochopen­, jak jsou vizuln­ informace kdovny neurln­mi populacemi a jejich obvody. Celkov obraz, kter vyplynul z tohoto sil­, naznaÄuje, e vizuln­ informace jsou nejprve zpracovny sloitmi obvody v s­tnici a nslednÄ peneseny do vy­ch mozkovch struktur. Ukazuje se, e s­tnice i mozek si vyvinuly pozoruhodnÄ sofistikovan© vpoÄty pro extrakci tÄchto informac­. FunkÄn­ studie tÄchto neuronln­ch transformac­ byly provdÄny pomoc­ elektrofyziologickch nebo zobrazovac­ch technik. Tyto techniky omezovaly analzu prostorovch specializac­ s­tnice, a to buÄ poÄtem dostupnch elektrod (v elektrofyziologii) nebo velikost­ zorn©ho pole (FOV) (v zobrazovac­ch experimentech). Pro ukzku â zznamy aktivit gangliovch bunÄk s­tnice (RGC) byly omezeny na relativnÄ malou oblast (~ 200 x 200 um2) za pouit­ nejmodernÄj­ch zobrazovac­ch technik. Ve sv© diplomov© prci jsem prozkoumal novÄ vyvinutou metodu vyu­vaj­c­ FOV, kter je 40krt vÄt­ ve srovnn­ s FOV konvenÄn­ch optickch metod, co mi umoilo pekonat toto technick© omezen­. Prce vyu­v tuto novou zobrazovac­ metodu k prozkoumn­ populaÄn­ch charakteristik smÄrovÄ selektivn­ch gangliovch bunÄk (DSGC) v s­tnic­ch my­. Replikac­ ji znmch populaÄn­ch vzorc jsme verifikovali, e nae nov zobrazovc­ metoda funguje. Prce dle zkoum Äinky pomocnch ltek pro zven­ m­ry infekce RGCs. Tyto pomocn© ltky tak mohou potencilnÄ usnadnit nezaujat© zaznamenvn­ aktivit RGCs. Prce nav­c pedstavuje nov stimul pro inspekci receptivn­ch pol­ (RF) RGCs. Tento nov stimul pekonv konvenÄn­ stimuly pou­van© v souÄasnch studi­ch jak v rozlien­ vyprodukovan©ho RF, tak v nezbytn©m Äase prezentace stimulu a otev­r tak dvee pro nsleduj­c­ studie, kter© mohou poprv© popsat distribuÄn­ vzorce receptivn­ch poli nap­Ä s­tnic­ a zlepit tak klasifikaci bunÄÄnch t­d.

Výpočetní tomografie je nástroj pro nedestruktivní inspekci vzorků, který je běžně používán v mnoha oblastech průmyslu a výzkumu. Některé tomografické přístroje umožňují snímání obrazů s prostorovým rozlišením pod jeden mikrometr. Zorné pole takovýchto přístrojů bývá malé, v rozsahu jednotek milimetrů či méně. Tím jsou omezeny rozměry vzorků, což je značně limitující. Toto omezení lze překonat pomocí různých technik pro rozšíření zorného pole. Jedna takováto dříve publikovaná metoda byla v této práci upravena a implementována pro přístroj Rigaku Nano3DX. Tato technika téměř zdvojnásobuje zorné pole přístroje bez nutnosti většího detektoru. Implementovaný přístup byl testován pomocí umělých i skutečných dat, a jeho účinnost byla zhodnocena subjektivně i objektivně, pomocí vizuální kontroly a metrik kvality obrazu. Hodnocení je převážně založeno na srovnání obrazů rekonstruovaných pomocí této metody s obrazy získanými pomocí většího detektoru. Implementovaná technika rozšíření zorného pole poskytuje věrné rekonstrukce vzorku, srovnatelné se zmíněnými protějšky.

This thesis describes types and parameters of memories used in communication engineering. The memory is a device which is able to record and to save information for the certain period of time. The memory is used in computers, measuring devices, consumer electronics etc. Main parameters of the memory are capacity, data stream speed, price of bit and time of memory cycle. The first part of this thesis deals with two types of memory – external and internal. External memories are removable media such as discs and magnetic tapes used for information saving and data backup for longtime period. Inner memories – in the form of semiconductive components – are mostly attached to the main panel. There are two types of inner memories – RAM (random access memory) and ROM (read only memory). The memories could be further divided according to their dependence on feeding used for memory saving. Types of memories used in switching exchanges are also mentioned in this part. The next part discusses the scheme of T switch for the first level of European PDH E1. The space switch and the time switch T belongs to switches used in digital switching exchange. In this part, the T switch, in particular the switch TR with controlled reading and the switch TW with controlled writing are described into details such as its parameters and methods of control. Furthermore, the calculation of call memory and control memory extant in E1 and E2 hierarchy are presented as well as the memory reading time and writing time of T switch in E1 and E2 hierarchy. The result of this thesis is a design of digital switching field animation that consists of four T switches. All operations, which are used in building linking of digital switching field, are shown in this animation.

This thesis concludes a description of construction and functions of Electronically commutated motors. The main target is modelling of thermal field of Electronically commutated motors. For modelling was chosen Ansys Workbench setting with CAD geometry. There was a measurement for verifying result of simulation, and its proof is described in my thesis. This project also concludes comparison of results from simulation itself and results obtained from measuring thermal profile of EC motor.

This work presents development system LabVIEW and the possibility to create virtual measuring devices. Particular realization of virtual measuring device within the frame of this work is applied on measurement of basic characteristics of claw-pole alternator. The structure and the principle of function of this alternator is described in brief. Created virtual measurement device is described in detail. The entire block scheme, that is the source code for LaBVIEW development system, is attached only in electronic form. The printed version contains front panel of the device and almost all the structures of block scheme.

This work deals with simple fluxmeter which is able, together with other device, to show hysteresis loop. Hysteresis loop is a graphic expression of dependence of magnetic induction on intensity of magnetic field. Oscilloscope is used to display the hysteresis loop. This device is fully sufficient for the display. The measured objects are solenoids from various kinds of materials with the same shape. The main aim of this work is the design, realization and description of the fluxmeter. The fluxmeter consists of several partial blocks. The first one, on which this work is focused, is signal generator which is able to generace different kinds of signal. The generated signal comes on primary winding of solenoid where a magnetic field on a given intensity rises. An amplifier is used to obtain the sufficient intensity. Next thing this work is focused on is the design of the integrator which is necessary for the correct function of the fluxmeter. As suggested, there is shown the block diagram of linking of individual parts. There are described the measured results at the end of this work.

The work deals with n-channel system enabling many sample analysis at sort time from sensor array using electrochemical methods. The 8x12 sensor arrays are formed from 3 electrodes system created on PCB which can be used for heavy metal analysis and toxic substances determination. The control unit switches each 3 electrode sensor to 8 channel precise potentiostat which was designed for electrochemical analysis with current sensitivity below 10 pA. The potentiostat can synchronize with control unit. Developed system is able to measure up to eight single inputs and may be simply converted to measure other nonchemical values. Measured data will be sent to user-friendly application in computer and analyzed or saved consequently.