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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.
31

Podpora výuky systémů elektrické požární signalizace / Support for instruction in electric fire alarm systems

Macinka, Jiří January 2008 (has links)
The master’s thesis „Support for instruction in electric fire alarm system” describes principles and engineering solution of electric fire alarm system. It is background for activity task about EPS for students in VUT in Brno. It illustrates how to act on this task and configuration fire panel and components EPS with the support of software FSP 5000. The practice contains proposal EPS with support in fire system designer.
32

Validation of the Fluorescence Polarization Assay (FPA) for the diagnosis of Bovine Brucellosis

Skosana, Banele Irene 03 1900 (has links)
Abstracts in English and Zulu / Fluorescence polarization assay (FPA), a serological assay, was validated as an alternative test for the rapid and cost-effective diagnosis of bovine brucellosis, with the aim of improving the control of brucellosis in South Africa. The FPA is anticipated to distinguish between vaccinated and infected cattle, circumventing the challenge associated with the tests that are currently used. Positive cattle serum samples (n =420) confirmed by Complement Fixation Test were tested in conjunction with serum samples (n = 446) from non-infected cattle initially tested on Rose Bengal Test, CFT and compared with FPA. The optimum cut-off value that offers the highest diagnostic sensitivity (Dsn) and diagnostic specificity (Dsp) was determined as 87 mP with the use of ROC analysis. The Dsn and Dsp of FPA using this cut-off value was calculated at 99.09% - 100% and 68.09%- 76.61% respectively with a 95% confidence interval (cl). The area under curve (AUC) was calculated at 0.9842 with a 95% standard error (S.E) of 0.005532 with positive and negative likelihood ratio (+LR) (-LR) at 3.643 and 1.002, respectively. The FPA was found to be as effective as CFT and should be considered because of its accuracy and other advantages such as speed, high throughput and the objectivity of the interpretation of results that can be obtained electronically by the (PHERAstar) machine. The test should be included in routine serological diagnosis for brucellosis. / I- Fluorescence polarization assay (i-FPA) ukuhlolwa kwe-serological okuqinisekiswe njengenye indlela yokuhlola ukuxilongwa okusheshayo nengabizi kwe-bovine brucellosis, okuzokwenza ngcono ukulawulwa kwe-brucellosis eNingizimu Afrika. Ngaphezu kwalokho, i-FPA kulindeleke ukuthi yehlukanise phakathi kwezinkomo ezigonyiwe nezithelelekile futhi lokhu kuzonciphisa inselelo ehambisana nokuhlolwa esetshenziswa njengamanje. Amasampula amahle avumayo we-serum ezinkomo (n = 420) aqinisekiswa yi-CFT ahlolwe ngokuhlangana namasampula e-serum (n = 446) avela ezinkomeni ezingathelelekile ezahlolwa kuqala ku-RBT, CFT futhi kuqhathaniswa ne-FPA. Inani elinqunyiwe elikhulu elinikezela ukuzwela okuphezulu kokuxilonga (i-Dsn) kanye nokucaciswa kokuxilongwa (i-Dsp) kunqunywe njenge-87 mP kusetshenziswa ukuhlaziywa kwe-ROC. I-Dsn ne-Dsp ye-FPA esebenzisa leli nani elisikiwe libalwe ngama-99.09% - 100% no-68.09% - 76.61% ngokulandelana kwesikhathi sokuzethemba esingu-95% (cl). Indawo engaphansi kwe-Curve noma ijika thizeni (i-AUC) ibalwe ku-0.9842 enephutha elingu-95% elijwayelekile (SE) lika- 0.005532 elinezilinganiso ezinhle nezimbi ze-likehood (+ LR) (-LR) ngo-3.643 no- 1.002, ngokulandelana. I-FPA isebenza njenge-CFT futhi kufanele ibhekwe ngenxa yokunemba eneqiniso kwayo nezinye izinzuzo ezifana nejubane lokuthola imiphumela kanye nenhloso yokuchazwa kwemiphumela engatholakala ngomshini wekhomphuyitha (PHERAstar), i-FPA kufanele ifakwe ekuhlolweni okuvamile ngokujwayelekile kwe-serological ye-brucellosis. / Agriculture and  Animal Health / M. Sc. (Agriculture)
33

On millimeter and submillimeter wave focal plane arrays implemented with MEMS waveguide switches

Frid, Henrik January 2017 (has links)
This thesis presents research towards enabling micromachined millimeter and submillimeter wave focal plane arrays (FPAs). The FPAs operate under the following principle: a switch network consisting of microelectromechanical (MEMS) switches, integrated with micromachined waveguides, is used to feed an array of antenna elements, located in the focal plane of a high-gain quasi-optical system. Hence, it is possible to switch between a set of narrow beams in different directions. Such beam steering systems are needed for future millimeter and submillimeter wave imaging and communication systems. The contributions to future MEMS-switchable FPAs presented here are organized in three papers, as described below. Paper I presents a criterion on the spacing between adjacent FPA elements which results in -3 dB overlap between the switched beams, for the special case when an extended hemispherical dielectric lens is used as the optical system. A key step towards this criterion is a closed-form relation between the scan angle and the FPA element's position, which results in an expression for the effective focal length of extended hemispherical lenses. A comparison with full-wave simulations demonstrates an excellent agreement with the presented theoretical results. Finally, it is shown that the maximum feasible FPA spacing when using an extended hemispherical lens is about 0.7 wavelengths. Paper II presents a numerical study of silicon-micromachined planar extended hemispherical lenses, with up to three matching regions used to reduce internal reflections. The effective permittivity of the matching regions is tailor-made by etching periodic holes in the silicon wafer. The optimal thickness and permittivity of the matching regions were determined using TRF optimization, in order to yield the maximum wide-band aperture efficiency and small side-lobes. We introduce a new matching region geometry, referred to as shifted-type matching regions, and it is demonstrated that using three shifted-type matching regions results in twice as large aperture efficiency as compared to using three conventional concentric-type matching regions. Paper III presents a submillimeter-wave single-pole single-throw (SPST) 500-750 GHz MEMS waveguide switch, based on a MEMS-reconfigurable surface inserted between two waveguide flanges. A detailed design parameter study is carried out to select the best combination of the number of horizontal bars and vertical columns of the MEMS-reconfigurable surface, for achieving a low insertion loss in the transmissive state and a high isolation in the blocking state. A method is presented to model the non-ideal electrical contacts between the vertical cantilevers of the MEMS surface, with an excellent agreement between the simulated and measured isolation. It is shown that the isolation can be improved by replacing an ohmic contact by a new, capacitive contact. The measured isolation of the switch prototype is better than 19 dB and the measured insertion loss is between 2.5 and 3 dB. / Denna avhandling presenterar forskning som syftar till att möjliggöra fokalplans-gruppantenner (FPAs) för våglängder i millimeter och submillimeterområdet. Principen för en sådan FPAs funktion är följande: ett nätverk bestående av mikroelektromekaniska (MEMS) switchar, används för att välja mellan de olika antenn-elementen i en gruppantenn, som placerats i fokalplanet av ett optiskt system. Därmed blir det möjligt att välja från en uppsättning av smala lober i olika riktningar. Sådana lob-styrningssystem behövs för framtida radar- och kommunikationssystem i millimeter och submillimeterområdet. Resultaten är uppdelade i tre vetenskapliga artiklar, som beskrivs nedan. I den första artikeln (Paper I) presenteras ett villkor för avståndet mellan närliggande FPA-element som resulterar i -3 dB överlappning mellan de switchade loberna, för specialfallet då en förlängd hemisfärisk lins används som optiskt system. Det viktigaste steget mot att hitta detta villkor är att bestämma en analytisk relation mellan avsökningsvinkeln och FPA-elementens position. Detta resulterar i ett uttryck för den effektiva fokallängden för denna typ av lins. En utmärkt överensstämelse har funnits mellan dessa relationer och simuleringar. Slutligen visas det att de största möjliga FPA-avstånden för en förlängd hemisfärisk lins är ungefär 0.7 våglängder, vilket uppnås för linser med låg permittivitet. I den andra artikeln (Paper II) presenteras en numerisk studie av plana förlängda hemisfäriska linser, som kan produceras från en kiselskiva. Linserna har upp till tre matchningsregioner, som används för att reducera interna reflektioner. Den effektiva permittiviteten av de matchande regionerna skräddarsys genom etsning av periodiska hål i kiselskivan. Den optimala tjockleken och permittiviteten av de matchande regionerna har bestämts med hjälp av TRF-optimering, för att ge maximal bredbandig direktivitet och minimala sidlober. En ny geometri introduceras för matchningsregionerna, som vi kallar matchningsregioner av skiftad typ. Vi visar att användning av tre matchningsregioner av skiftad typ resulterar i en dubbelt så hög apertur-effektivitet, jämfört med att använda tre konventionella matchningsregioner av koncentrisk typ. I den tredje artikeln (Paper III) presenteras en MEMS-switch för rektangulära vågledare, för frekvensområdet 500-750 GHz. Baserat på en designparameterstudie har den bästa kombinationen av antalet horisontella rader och vertikala kolumner hos den MEMS-konfigurerbara ytan valts ut, för att uppnå låga förluster i det öppna tillståndet och hög isolation i det blockerande tillståndet. I artikeln presenteras en metod för att modellera icke-perfekta elektriska kontakter mellan de fixerade och de rörliga delarna i MEMS-ytan. Denna metod uppvisar en utmärkt överensstämmelse mellan den simulerade och den uppmätta isolationen. Vi visara att isolationen kan förbättras med hjälp av en ny typ av kapacitiv kontakt. Den uppmätta isolationen hos den presenterade switch-prototypen är högre än 19 dB, och den uppmätta förlusten är mellan 2.5 och 3 dB. / <p>QC 20161206</p>
34

FTIR-ATR spectroscopic and FTIR-FPA microscopic investigations on panel board production processes using Grand fir (Abies grandis (Douglas ex D. Don) Lindl.) and European beech (Fagus sylvatica L.) / FTIR-ATR spektroskopische und FTIR-FPA mikroskopische Untersuchungen an Produktionsprozessen von Holzwerkstoffplatten aus Küstentanne (Abies grandis) und Rotbuche (Fagus sylvatica L.)

Müller, Günter Stefan 06 June 2008 (has links)
No description available.
35

Polymer-silica Hybrids for Separation of CO2 and Catalysis of Organic Reactions

Silva Mojica, Ernesto 15 May 2014 (has links)
No description available.

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