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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Konstrukce naklápěcího otočného stolu / Design of tilting rotary table

Hanzlík, Aleš January 2011 (has links)
The aim of this thesis is the design of the rotary tilting table controlled the fourth and fifth axis for CNC centrum.První part includes the search for pivotally tilting tables. The second part includes the choice of technical paremetrů pivotally tilting table for selected CNC center, design of possible options , selection of appropriate options, design of the selected option.
62

Detecting Anomalous Behavior in Radar Data

Rook, Jayson Carr 01 June 2021 (has links)
No description available.
63

Enviromentální vědeckotechnický park v Zábřehu / Enviromental Science & Technology Park in Zábřeh

Kratochvílová, Šárka January 2009 (has links)
Diploma project develops the intention to build up an ecological project based on renewable resources utilization of energy and materials recycling in Zábřeh. The study is engaged in possible area extension and tries to divide it into functional zones, when zone of main production remains the same (already elaborated project) and the zone of extension where there is settled production storages, alt.production hall extension. Third zone, so-called green zone, is developed in more detail. The green zone is a belt of plot separating the production area from second-class road nr.315, and also creates entrance gateway and lungz of the whole area. The green belt is conceived as a sojourn park with water elements(biotopes, lake, water basin), which is intersected by wooden footbridge, that connects object of multifunction pavilion and office building and ends at articifial island, or more precisely as a torso in the lake waters, symbolizing the science, which´s end is far away for human beings. The footbridge is also an axis between planned science-technological centres for the direct processing of waste materials. Administration building and pavilion are conceived as a „second nature“, purely human artifact, whih is also clearly expressed in „non-natural“ materials used. Their concept tries to saturate client´s requests and use the renewable resources of energy with observance of building biology principles (author´s request) at the same time.
64

Ett multifunktionellt leksakskök för en hållbar konsumtion : Hur produktdesign kan bidra till en mer hållbar konsumtion genom att skapa multifunktionella leksakskök för barn / A multifunctional toy kitchen for sustainable consumption : How product design can contribute to a more sustainable consumption by creating a multifunctional toy kitchen for children

Persson, Elida January 2024 (has links)
Studien utgår ifrån design för hållbar utveckling och användarcentrerad design för att besvara frågeställningen: Hur kan man med hjälp av produktdesign bidra till en mer hållbar konsumtion genom att skapa multifunktionella leksakskök för barn? Frågan undersöks utifrån multifunktionell design. Syftet är att göra det enklare för konsumenter att konsumera hållbart. Designbidraget ger barn ett användbart leksakskök som kan användas till flera ändamål. Kunskapsbidraget bidrar med kunskap om hur man kan designa hållbara leksaker med fokus på multifunktion. Genom workshop med användare samt intervjuer med föräldrar och experter undersöks vilka kriterier som designbidraget måste uppnå. Vidare genereras idéer genom brainstorming och prototypande. Efter en återkoppling med användarna väljs ett designförslag ut som utvecklas, utvärderas och förfinas. Slutligen presenterar studien ett designbidrag som är ett förslag på utformning för att besvara frågeställningen. Designbidraget är ett multifunktionellt leksakskök som med samma ursprungliga resurser kan omvandlas till en bil eller koja, utifrån användarnas önskemål. Studiens slutsats är att integration av flera lekar i en leksak gör det möjligt att optimera resursanvändningen. / The study is based on design for sustainability and user-centered design to answer the research question: How can product design contribute to a more sustainable consumption by creating a multifunctional toy kitchen for children? Research is carried out through a multifunctional design perspective. The aim is to make it easier for consumers to consume sustainably. The design contribution gives children a useful toy kitchen that can be used for several purposes. The contribution of knowledge brings knowledge about designing sustainable toys with a focus on multifunction. Through workshops with users as well as interviews with parents and experts, it is determined which criteria’s the final design contribution must meet. Furthermore, ideas are generated through brainstorming and prototyping. After feedback with the users, a design proposal is selected which is further developed, evaluated and refined. Finally, the study presents a design contribution which is an alternative on how to answer the research question. The design contribution is a multifunctional toy kitchen which, with the same original resources, can be transformed into a car or hut, based on the users’ desires. The conclusion of the study is that integration of several different plays in one toy makes it possible to optimize the use of resources.
65

Studies on Multifrequensy Multifunction Electrical Impedance Tomography (MfMf-EIT) to Improve Bio-Impedance Imaging

Bera, Tushar Kanti January 2013 (has links) (PDF)
Electrical Impedance Tomography (EIT) is a non linear inverse problem in which the electrical conductivity or resistivity distribution across a closed domain of interest is reconstructed from the surface potentials measured at the domain boundary by injecting a constant sinusoidal current through an array of surface electrodes. Being a non-invasive, non-radiating, non-ionizing, portable and inexpensive methodology, EIT has been extensively studied in medical diagnosis, biomedical engineering, biotechnology, chemical engineering, industrial and process engineering, civil and material engineering, soil and rock science, electronic industry, defense field, nano-technology and many other fields of applied physics. The reconstructed image quality in EIT depends mainly on the boundary data quality and the performance of the reconstruction algorithm used. The boundary data accuracy depends on the design of the practical phantoms, current injection method and boundary data measurement process and precision. On the other hand, the reconstruction algorithm performance is highly influenced by the mathematical modeling of the system, performance of the forward solver and Jacobian computation, inverse solver and the regularization techniques. Hence, for improving the EIT system performance, it is essential to improve the design of practical phantom, instrumentation and image reconstruction algorithm. As the electrical impedance of biological materials is a function of tissue composition and the frequency of applied ac signal, the better assessment of impedance distribution of biological tissues needs multifrequency EIT imaging. In medical EIT, to obtain a better image quality for a complex organ or a body part, accurate domain modelling with a large 3D finite element mesh is preferred and hence, the computation speed becomes very expensive and time consuming. But, the high speed reconstruction with improved image quality at low cost is always preferred in medical EIT. In this direction, a complete multifrequency multifunction EIT (MfMf-EIT) system is developed and multifrequency impedance reconstruction is studied to improve the bioimpedance imaging. The MfMf-EIT system consists of an MfMf-EIT instrumentation (MfMf-EITI), high speed impedance image reconstruction algorithms (IIRA), a Personal Computer (PC) and a number of practical phantoms with EIT sensors or electrodes. MfMf-EIT system and high speed IIRA are studied tested and evaluated with the practical phantoms and the multifrequency impedance imaging is improved with better image quality as well as fast image reconstruction. The MfMf-EIT system is also applied to the human subjects and the impedance imaging is studied for human body imaging and the system is evaluated. MfMf-EIT instrumentation (MfMf-EITI) consists of a multifrequency multifunction constant current injector (MfMf-CCI), multifrequency multifunction data acquisition system (MfMf DAS), a programmable electrode switching module (P-ESM) and a modified signal conditioner blocks (M-SCB) or data processing unit (DPU). MfMf-CCI, MfMf-DAS, P-ESM and M-SCBs are interfaced with a LabVIEW based data acquisition program (LV-DAP) controlled by a LabVIEW based graphical user interface (LV-GUI). LV-GUI controls the current injection and data acquisition with a user friendly, fast, reliable, efficient measurement process. The data acquisition system performance is improved by the high resolution NIDAQ card providing high precision measurement and high signal to noise ratio (SNR). MfMf-EIT system is developed as a versatile data acquisition system with a lot of flexibilities in EIT parameter selection that allows studying the image reconstruction more effectively. MfMf-EIT instrumentation controls the multifrequency and multifunctioned EIT experimentation with a number of system variables such as signal frequency, current amplitude, current signal wave forms and current injection patterns. It also works with either grounded load CCI or floating load CCI and collects the boundary data either in grounded potential form or differential form. The MfMf-EITI is futher modified to a battery based MfMf-EIT (BbMfMf-EIT) system to obtain a better patient safety and also to improve the SNR of the boundary data. MfMf-EIT system is having a facility of injecting voltage signal to the objects under test for conducting the applied potential tomography (APT). All the electronic circuit blocks in MfMf-EIT instrumentation are tested, evaluated and calibrated. The frequency response, load response, Fast Fourier Transform (FFT) studies and DSO analysis are conducted for studying the electronic performance and the signal quality of all the circuit blocks. They are all evaluated with both the transformer based power supply (TBPS) and battery based power supply (BBPS). MfMf-DAS, P-ESM and LV-DAP are tested and evaluated with digital data testing module (DDTM) and practical phantoms. A MatLAB-based Virtual Phantom for 2D EIT (MatVP2DEIT) is developed to generate accurate 2D boundary data for assessing the 2D EIT inverse solvers and its image reconstruction accuracy. It is a MATLAB-based computer program which defines a phantom domain and its inhomogeneities to generate the boundary potential data by changing its geometric parameters. In MatVP2DEIT, the phantom diameter, domain discretization, inhomogeneity number, inhomogeneity geometry (shape, size and position), electrode geometry, applied current magnitude, current injection pattern, background medium conductivity, inhomogeneity conductivity all are set as the phantom variables and are chosen indipendently for simulating different phantom configurations. A constant current injection is simulated at the phantom boundary with different current injection protocols and boundary potential data are calculated. A number of boundary data sets are generated with different phantom configurations and the resistivity images are reconstructed using EIDORS (Electrical Impedance Tomography and Diffuse Optical Tomography Reconstruction Software). Resistivity images are evaluated with the resistivity parameters and contrast parameters estimated from the elemental resistivity profiles of the reconstructed impedance images. MfMf-EIT system is studied, tested, evaluated with a number of practical phantoms eveloped with non-biological and biological materials and the multifrequency impedance imaging is improved. A number of saline phantoms with single and multiple inhomogeneities are developed and the boundary data profiles are studied and the phantom geometry is modified. NaCl-insulator phantoms and the NaCl-vegetable phantoms with different inhomogeneity configurations are developed and the multifrequency EIT reconstruction is studied with different current patterns, different current amplitudes and different frequencies using EIDORS as well as the developed IIRAs developed in MATLAB to evaluate the phantoms and MfMf-EIT system. Real tissue phantoms are developed with different chicken tissue backgrounds and high resistive inhomogeneities and the resistivity image reconstruction is studied using MfMf-EIT system. Chicken tissue phantoms are developed with chicken muscle tissue (CMTP) paste or chicken tissue blocks (CMTB) as the background mediums and chicken fat tissue, chicken bone, air hole and nylon cylinders are used as the inhomogeneity to obtained different phantom configurations. Resistivity imaging of all the real tissue phantoms is reconstructed in EIDORS and developed IIRAs with different current patterns, different frequencies and the images are evaluated by the image parameters to assess the phantoms as well as the MfMf-EIT system. Gold electrode phantoms are developed with thin film based flexible gold electrode arrays for improved bioimpedance and biomedical imaging. The thin film based gold electrode arrays of high geometric precision are developed on flexible FR4 sheet using electro-deposition process and used as the EIT sensors. The NaCl phantoms and real tissue phantoms are developed with gold electrode arrays and studied with MfMf-EIT system and and the resiulsts are compared with identical stainless steel electrode phantoms. NaCl phantoms are developed with 0.9% NaCl solution with single and multiple insulator or vegetable tissues as inhomogeneity. Gold electrode real tissue phantoms are also developed with chicken muscle tissues and fat tissues or other high resistive objects. The EIT images are reconstructed for the gold electrode NaCl phantoms and the gold electrode real tissue phantoms with different phantom geometries, different inhomogeneity configurations and different current patterns and the results are compared with identical SS electrode phantoms. High speed IIRAs called High Speed Model Based Iterative Image Reconstruction (HSMoBIIR) algorithms are developed in MATLAB for impedance image reconstruction in Electrical Impedance Tomography (EIT) by implementing high speed Jacobian calculation techniques using “Broyden’s Method (BM)” and “Adjoint Broyden’s Method (ABM)”. Gauss Newton method based EIT inverse solvers repeatitively evaluate the Jacobian (J) which consumes a lot of computation time for reconstruction, whereas, the HSMoBIIR with Broyden’s Methods (BM)-based accelerated Jacobian Matrix Calculators (JMCs) provides the high speed schemes for Jacobian (J) computation which is integrated with conjugate gradient scheme (CGS) for fast impedance reconstruction. The Broyden’s method based HSMoBIIR (BM-HSMoBIIR) and Adjoint Broyden’s method based HSMoBIIR (ABM-HSMoBIIR) algorithm are developed for high speed improved impedance imaging using BM based JMC (BM-JMC) and ABM-based JMC (ABM-JMC) respectively. Broyden’s Method based HSMoBIIR algorithms make explicit use of secant and adjoint information that can be obtained from the forward solution of the EIT governing equation and hence both the BM-HSMoBIIR and ABM-HSMoBIIR algorithms reduce the computational time remarkably by approximating the system Jacobian (J) successively through low-rank updates. The impedance image reconstruction is studied with BM-HSMoBIIR and ABM-HSMoBIIR algorithms using the simulated and practical phantom data and results are compared with a Gauss-Newton method based MoBIIR (GNMoBIIR) algorithm. The GNMoBIIR algorithm is developed with a Finite Element Method (FEM) based flexible forward solver (FFS) and Gauss-Newton method based inverse solver (GNIS) working with a modified Newton-Raphson iterative technique (NRIT). FFS solves the forward problem (FP) to obtain the computer estimated boundary potential data (Vc) data and NRIT based GNIS solve the inverse problem (IP) and the conductivity update vector [Δσ] is calculated by conjugate gradient search by comparing Vc measured boundary potential data (Vm) and using the Jacobian (J) matrix computed by the adjoint method. The conductivity reconstruction is studied with GNMoBIIR, BM-HSMoBIIR and ABM-HSMoBIIR algorithms using simulated data a practical phantom data and the results are compared. The reconstruction time, projection error norm (EV) and the solution error norm (Eσ) produced in HSMoBIIR algorithms are calculated and compared with GNMoBIIR algorithm. Results show that both the BM-HSMoBIIR and ABM-HSMoBIIR algorithms successfully reconstructs the conductivity distribution of the domain under test with its proper inhomogeneity and background conductivities for simulation as well as experimental studies. Simulated and practical phantom studies demonstrate that both the BM-HSMoBIIR and ABM-HSMoBIIR algorithms accelerate the impedance reconstruction by more than five times. It is also observed that EV and Eσ are reduced in both the HSMoBIIR algorithms and hence the image quality is improved. Noise analysis and convergence studies show that both the BM-HSMoBIIR and ABM-HSMoBIIR algorithms works faster and better in noisy conditions compared to GNMoBIIR. In low noise conditions, BM-HSMoBIIR is faster than to ABM-HSMoBIIR algorithm. But, in higher noisy environment, the ABM-HSMoBIIR is found faster and better than BM-HSMoBIIR. Two novel regularization methods called Projection Error Propagation-based Regularization (PEPR) and Block Matrix based Multiple Regularization (BMMR) are proposed to improve the image quality in Electrical Impedance Tomography (EIT). PEPR method defines the regularization parameter as a function of the projection error contributed by the mismatch (difference) between the data obtained from the experimental measurements (Vm) and calculated data (Vc). The regularization parameter in the reconstruction algorithm gets modified automatically according to the noise level in measured data and ill-posedness of the Hessian matrix. The L-2 norm of the projection error is calculated using the voltage difference and it is used to find the regularization parameter in each iteration in the reconstruction algorithm. In BMMR method, the response matrix (JTJ) obtained from the Jacobian matrix (J) has been partitioned into several sub-block matrices and the highest eigenvalue of each sub-block matrices has been chosen as regularization parameter for the nodes contained by that sub-block. The BMMR method preserved the local physiological information through the multiple regularization process which is then integrated to the ill-posed inverse problem to make the regularization more effective and optimum for all over the domain. Impedance imaging with simulated data and the practical phantom data is studied with PEPR and BMMR techniques in GNMoBIIR and EIDORS and the reconstructed images are compared with the single step regularization (STR) and Modified Levenberg Regularization (LMR). The projection error and the solution error norms are estimated in the reconstructions processes with PEPR and the BMMR methods and the results are compared with the errors estimated in STR and modified LMR techniques. Reconstructed images obtained with PEPR and BMMR are also studied with image parameters and contrast parameters and the reconstruction performance with PEPR and BMMR are evaluated by comparing the results with STR and modified LMR. PEPR and BMMR techniques are successfully implemented in the GNMoBIIR and EIDORS algorithms to improve the impedance image reconstruction by regularizing the solution domain in EIT reconstruction process. As the multifrequency EIT is always preferred in biological object imaging for better assessments of the frequency dependent bioimpedance response, multifrequency impedance imaging is studied with MfMf-EIT system developed for biomedical applications. MfMf-EIT system is studied, tested and evaluated with practical phantoms suitably developed for multifrequency impedance imaging within a wide range of frequency. Different biological materials are studied with electrical impedance spectroscopy (EIS) and a number of practical biological phantoms suitable for multifrequency EIT imaging are developed. The MfMf-EIT system is studied, tested and evaluated at different frequency levels with different current patterns using a number of NaCl phantoms with single, multiple and hybrid vegetable tissue phantoms as well as with chicken tissue phantoms. BbMfMf-EIT system is also studied and evaluated with the multifrequency EIT imaging using the developed biological phantoms. The developed MfMf-EIT system is applied on human body for impedance imaging of human anatomy. Impedance imaging of human leg and thigh is studied to visualize the muscle and bone tissues using different current patterns and different relative electrode positions. Ag/AgCl electrodes are attached to the leg and thigh using ECG gel and the boundary data are collected with MfMf-EIT EIT system by injecting a 1 mA and 50 kHz sinusoidal constant current with neighbouring and opposite current injection patterns. Impedance images of the femur bone of the human thigh and the tibia and fibula bones of the human leg along with the muscle tissue backgrounds are reconstructed in EIDORS and GNMoBIIR algorithms. Reconstructed resistivity profiles of bone and muscles are compared with the resistivity data profiles reported in the published literature. Impedance imaging of leg and thigh is studied with MfMf-EIT system for different current patterns, relative electrode positions and the images are evaluated to assess the system reliability. Battery based MfMf-EIT system (BbMfMf-EIT) is also studied for human leg and thigh imaging and it is observed that MfMf-EIT system and BbMfMf-EIT system are suitable for impedance imaging of human body imaging though the BbMfMf-EIT system increases the patiet safety. Therefore, the developed MfMf-EIT and BbMfMf-EIT systems are found quite suitable to improve the bio-impedance imaging in medical, biomedical and clinical applications as well as to study the anatomical and physiological status of the human body to diagnose, detect and monitor the tumors, lesions and a number of diseases or anatomical abnormalities in human subjects.
66

Konstrukční návrh lineární osy pro multifunkční obráběcí centrum / Design of linear axis for heavy machine tool

Dostál, Martin January 2021 (has links)
This diploma thesis is concerned with providing a construction proposal of a linear axis X for multifunctional machining center. Moreover, this work presents characterisations of machining centers, overview of manufacturers, list of main construction components used in the linear axis, their evaluation, assessment of various options for construction, which are then explained further. These detailed construction methods include calculations with the subsequent choice of feed system component. Ultimately, final evaluation of chosen option is provided as well. Another section of this thesis is also an economical assessment and 3D model alongside with mechanical drawing.
67

Multifunkční display pro pozemní zdroj / Multifunction display for ground power supply

Kincl, Zdeněk January 2009 (has links)
The aim of this thesis was to design a concept and circuit for multifunction display. This unit is used in ground power supply for preflighting preparation of army helicopters. Multifunction display measures voltages and currents of AC and DC generators, teperatures of cooling air and fuel quantity. Display indicates a operational and fault states of ground power supply. The main element of multifunction display is 32-bit microprocessor from the manufacturer NXP, family ARM7. All information are displaying on graphic vacuum fluorescent display GU256x128.
68

Víceúčelová sportovní hala / Multifunction sports hall

Nacházel, Jakub January 2014 (has links)
This master’s thesis deals with the design documentation multifunction sports hall. The building is situated in the region in the Vysočina village Humpolec, cadastral district Humpolec. The building is designed as a prefabricated skeleton, where the vertical load-bearing structures are designed from the prefabricated skeleton of PREFA BRNO and filling and partition walls of the structural system POROTHERM and BTB fittings. Horizontal structures are formed by the supporting elements prefabricated skeleton system of PREFA BRNO and ceiling panels SPIROLL. The main single-storey multifunction hall is roofed with wooden trusses of curved from glued laminated timber and purlins carrying roof deck. The other part of the building is covered with flat single-ply roofs. The building is divided into a main single-storey multifunction sports hall and an outbuilding with facilities for athletes and spectators about two floors above ground and a third technical floor. The building is solved as barrier-free.
69

Design výukové konzole / Design of education board

Hadáček, Milan January 2008 (has links)
The aim of my diploma thesis is to blueprint a design of multi-functional educational console. The dissertation contains several variant studies, color drawings and concrete shape execution. It entails a certain development in the area of positioning and multi-functional appliances. The thesis itself deals with the concrete shape execution of multi-touch educational console as well as seat in the form of gym ball. Short video cut from the area of interactive media forms a part of my work too.
70

Dynamické vlastnosti osy C pro multifunkční soustružnické centrum / Dynamic Behaviours of the C Axis Drive for Multifunction Cutting Center

Křepela, Jan January 2011 (has links)
his Disertation thesis involves the creating of the simulation model of the C axis drive over mentioned machine and them verification on the prototype of this machine. C axis is controlled with position feedback. Simulation model was created before the realisation of the machine prototype for the preliminary identification of the dynamic behaviours in the working cycles and them opportunity of the realisation this conception. C axis is constructed with worm gear and is controlled with help of Master-Slave drive. This torque drive eliminates the production backlash in the worm gear. The multifunction turning center, where is used this C axis, is determinate for heavy duty roughing cutting of the forged peaces, where is problem with dynamic stability of the cutting process. Simulation model includes the problems with multi-body mass system, friction on the worm gear, self locking, damping on the worm gear and the optimization of the parametrs for many regulators. Simulation model was verified on the prototype of the machine. Achieved results bring the new knowledge, which are used for simulation complicated machine nodes and this knowledge is used for research and developing of the similar mechatronics system.

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