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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.
121

Measurement System for Microwave Imaging Towards a Biomedical Application

Petrović, Nikola January 2014 (has links)
Microwave imaging techniques have shown excellent capabilities in various fields such as civil engineering, nondestructive testing, industrial applications, and have in recent decades experienced strong growth as a research topic in biomedical diagnostics. Many research groups throughout the world work on prototype systems for producing images of human tissues in different biomedical applications, particularly breast tumor detection. However, the research community faces many challenges and in order to be competitive to other imaging modalities one of the means is to put emphasis on experimental work. Consequently, the use of flexible and accurate measurement systems, together with the design and fabrication of suitable antennas, are essential to the development of efficient microwave imaging systems. The first part of this thesis focuses on measurement systems for microwave imaging in terms of antenna design and development, robot controlled synthetic array geometries, permittivity measurements, and calibration. The aim was to investigate the feasibility of a flexible system for measuring the fields around an inhomogeneous object and to create quantitative images. Hence, such an aim requires solving of a nonlinear inverse scattering problem, which in turn requires accurate measurements for producing good quality experimental data. The presented solution by design of a flexible measurement system is validated by examination of microwave imaging from experimental data with a breast phantom. The second part of the thesis deals with the research challenges of designing high performance antennas to be placed in direct contact with or in close proximity to the imaged object. The need for novel antenna applicators is envisaged in the framework of the Mamacell measurement system, where the antenna applicators have to be designed and constructed to effectively couple the energy into the imaging object. For this purpose the main constraints and design requirements are a narrow lobe of the antenna, very small near-field effects, and small size. Numerical simulations and modeling shows that the proposed ridged waveguide antenna is capable of fulfilling the design requirements and the performance goals, demonstrating the potential for the future microwave imaging system called Mamacell.
122

Selection Of Light Source And Implementation Of Data Acquisition System Of An Optical Experimental Setup

Reyhanioglu, Erinc 01 January 2004 (has links) (PDF)
The construction of an optical experimental setup is the objective, to measure transmission coefficient of optical components used in plasma investigations. Thus, proper light source either with continuous or line radiation spectrum should be used. In addition, the detectors&rsquo / output signal is recorded on a PC based data recorder after being digitized by an analog to digital converter card.
123

Návrh dataloggeru provozních dat výrobního stroje / Design of datalogger for production machine

Gazda, Ondřej January 2018 (has links)
This thesis describes the design of the data datalogger for collecting the operating data of the machine tool. Dataloggers and data acquisition systems are used in scientific research as well as in the industry for recording and analyzing large amounts of data. The control unit of the proposed system is the National Instruments CompactRIO platform. System software is created in the LabVIEW programming environment and uses both the FPGA circuit and the real-time processor of the control unit. Measured data are stored on the unit and in the database. The measurement status is reported via email.
124

Aquisicao de dados em espectroscopia gama nuclear

BARG FILHO, DAVID 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:04Z (GMT). No. of bitstreams: 1 07068.pdf: 6722891 bytes, checksum: c0a7ba8c3ee901d4a4cb2946b283b9c6 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
125

Aquisicao de dados em espectroscopia gama nuclear

BARG FILHO, DAVID 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:04Z (GMT). No. of bitstreams: 1 07068.pdf: 6722891 bytes, checksum: c0a7ba8c3ee901d4a4cb2946b283b9c6 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
126

Získávání dat z tabletu / Tablet data acquisition

Zvak, Martin January 2010 (has links)
Reliable authorization and authentication is now becoming necessary for many everyday activities such as boarding an aircraft, doing financial transactions etc. This work deals with the possibility of proposing an appropriate method of acquisition, processing and evaluation of data from the tablet itself, focusing on the possibility of obtaining data from the graphics tablet used in conjunction with a personal computer, for the purpose of verifying identity. It contains an overview of biometrics, as independent developing science over the last decades of the 20th century to the present, a summary of the development of a graphics tablet, the current situation, a brief overview of the most popular technologies used in their construction and distribution. Furthermore, it focuses on the design and implementation of appropriate procedures to obtain data provided by the Trust tablet TB - 7300, using available software development kit for the Microsoft Tablet PC, and a comparison of WinForms and WPF model (.NET Framework), with the declaration of suitability for the use of the second one. Last but not least, according to the response from the available set of users, this work focuses on the design of appropriate types of input data, test patterns, method and application for collecting and processing data from the graphic tablet, as well as their use for the verification of the identity of the individual. Ultimately, it is possible to discuss the accuracy of the method on a set of users, its suitability for use and shortcomings. Based on the analysis of the issue, the proposed method can be declared as under-optimal - it is safe, but inaccurate with low stability and repeatability. It is also important to accent that this is just the initial proposal, the use of applications in everyday life is for current phase impossible and the transition from laboratory conditions would require further development and improvement of the process.
127

Návrh a implementace systému pro výměnu statistických informací o síťovém provozu mezi přístupové body WLAN sítě / Design and implementation of a system for exchange of statistic information on network traffic between access points of WLAN network

Lenk, Peter January 2012 (has links)
This thesis explores the possibilities of implementation of methods for data acquisition in wireless access point MikroTik while using virtualized OpenWRT system. First part of the paper contains short introduction into device’s features and extention of the features by virtualizing the operation system. Design and implementation of the scripts for average load of interfaces data acquisition is in the second part of the paper. The next part deals with the transmission of the gathered data and implementation of the proposed programs in C language. The last part of the paper covers the implementation of a complete program to collect, send and receive data with the option of parameters configuration, and automatic acquisition of the configuration.
128

VYTVOŘENÍ PROGRAMU PRO ZÁTĚŽOVÉ ZKOUŠKY EL.MOTORŮ-sběr dat ze systémů teplotních senzorů (RS232,USB,PCI DAQ) a výkonového analyzátoru (GPIB) v LabView / SOFTWARE FOR LOAD TESTS OF EL.MOTORS-data acquisiton from temp.sensors systems (RS232,USB,PCI DAQ) and power analyzer (GPIB) in LabView.

Čípek, Radek January 2011 (has links)
This thesis deals with the creation of a program for collecting data from three optional systems of temperature sensors (RS232, USB and PCI DAQ), torque shaft and a power analyzer (GPIB) in LabVIEW. The implementation of the results to Excel by the automatic periodical writing of the gained data (LabVIEW › Excel).
129

Development of the DAQ System of Triple-GEM Detectors for the CMS Muon Spectrometer Upgrade at LHC

Lenzi, Thomas 19 December 2016 (has links) (PDF)
The Gas Electron Multiplier (GEM) upgrade project aims at improving the performance of the muon spectrometer of the Compact Muon Solenoid (CMS) experiment which will suffer from the increase in luminosity of the Large Hadron Collider (LHC). After a long technical stop in 2019-2020, the LHC will restart and run at a luminosity of 2 10^34 cm^-2 s^-1, twice its nominal value. This will in turn increase the rate of particles to which detectors in CMS will be exposed and affect their performance. The muon spectrometer in particular will suffer from a degraded detection efficiency due to the lack of redundancy in its most forward region. To solve this issue, the GEM collaboration proposes to instrument the first muon station with Triple-GEM detectors, a technology which has proven to be resistant to high fluxes of particles. Within the GEM collaboration, the Data Acquisition (DAQ) subgroup is in charge of the development of the electronics and software of the DAQ system of the detectors.This thesis presents the work of the author as lead developer of the firmware for the front-end and back-end electronics. These developments have been performed from the ground up and designed to transfer data from the analog front-end to the off-detector electronics while offering extensive control and monitoring capabilities. The developed DAQ chain has been tested extensively during two test beam campaigns which provided results on both the stability of the system and the efficiency of the detectors. The results of these campaigns are described in the present thesis. Further characterization of the electronics is also described along with the procedures and tools built to qualify the components for their installation in CMS. Finally, the results of the irradiation tests performed on the on-detector electronics are presented. These allowed us to understand the effects of radiation on the electronic boards used for the GEM upgrade project and the impact that it has on the design of the firmware for CMS.Additionally, the work of the author on a new architecture for DAQ systems is described. The latter uses modified network topologies and novel web technologies to increase the available bandwidth on the network and yield an event-driven system. / Cette thèse de doctorat s'inscrit dans le projet de mise à niveau du spectromètre à muons du Compact Muon Solénoid (CMS) auprès du Large Hadron Collider (LHC). Après un arrêt pour maintenance prévu en 2019-2020, le LHC reprendra son programme de recherche à une luminosité de 2 $ imes$ 10^34 cm^-2 s^-1, soit deux fois sa valeur nominale. Ceci aura pour conséquence d'accroître le taux de particules auquel seront soumis les détecteurs de CMS et d'entraver l'efficacité de détection de ces derniers. Le spectromètre à muons de CMS sera tout particulièrement touché à cause du manque de redondance dans sa partie avant. Afin de palier à ce problème, il est proposé d'installer des détecteurs Gas Electron Multipliers (GEM) dans la première station à muons. La technologie GEM répond aux besoins de CMS en offrant une excellente efficacité de détection à de hauts flux de particules. Au sein de la collaboration GEM, le sous-groupe en charge du système d'acquisition de données (DAQ) doit développer l'électronique et les logiciels de gestion de la chaîne de lecture des détecteurs.Nous présentons ici le travail de l'auteur réalisé en tant que principal développeur du firmware pour l'électronique du système DAQ. Ces développements visent à créer une architecture qui achemine les données depuis l'électronique de lecture du détecteur jusqu'aux systèmes situés dans la zone de comptage, tout en offrant la possibilité de contrôler et surveiller l'ensemble des composants du DAQ. Le système mis en place a été largement testé durant deux campagnes de tests en faisceaux qui ont fourni des informations concernant la stabilité du DAQ ainsi que des mesures de l'efficacité des détecteurs. Nous décrivons également l'ensemble des travaux réalisés afin de caractériser les composants électroniques avant leur installation dans CMS ainsi que les résultats des tests d'irradiation effectués sur l'électronique du détecteur. Ces derniers permettent de mieux comprendre les conséquences des radiations sur le système et de développer des méthodes de mitigation.De plus, le travail de l'auteur sur la création d'une nouvelle architecture de système DAQ est décrit. Cette dernière combine les avancées récentes en terme de technologies web à une topologie de réseaux non-classique afin d'accroître la bande passante disponible et de créer un système réactif. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
130

Design, Implementation and Use of In-Process Sensor Data for Monitoring Broaching and Turning Processes: A Multi - Sensor Approach

Rathinam, Arvinth Chandar 02 June 2013 (has links)
Real-time quality monitoring continues to gain interest within the manufacturing domain as new and faster sensors are being developed. Unfortunately, most quality monitoring solutions are still based on collecting data from the end product. From a process improvement point of view, it is definitely more advantageous to proactively monitor quality directly in the process instead of the product, so that the consequences of a defective part can be minimized or even eliminated. In this dissertation, new methods for in-line process monitoring are explored using multiple sensors. In the first case, a new cutting force-based monitoring methodology was developed to detect out of control conditions in a broaching operation. The second part of this thesis focusses on the development of a test bed for monitoring the tool condition in a turning operation. The constructed test bed includes the combination of multiple sensors signals including, temperature, vibrations, and energy measurements. Here, the proposed SPC strategy integrates sensor data with engineering knowledge to produce quick, reliable results using proven profile monitoring techniques. While, the already existing methods are based on raw process data which requires more features to monitor without any loss of information. This technique is straight forward and able to monitor the process comprehensively with less number of features. Consequently, this also adds to the group of tools that are available for the practitioner. / Master of Science

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