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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.
1

Die Anfänge der Bekämpfung der IBR-IPV in der Schweiz, insbesondere im Kanton Graubünden /

Egger, Willi. January 1982 (has links)
Diss. vet.-med. Bern, 1982.
2

Ozdravovací program od IBR v rámci Opavského regionu

Kapusňaková, Jiřina January 2010 (has links)
No description available.
3

ZHODNOCENÍ PRŮBĚHU NÁRODNÍHO OZDRAVOVACÍHO PROGRAMU OD IBR VE VYBRANÝCH CHOVECH DVOU OKRESŮ / EVALUATION OF THE NATIONAL IBR ERADICATION PROGRAM IN THE SELECTED FARMS IN TWO REGIONS

INGVORTOVÁ, Miroslava January 2011 (has links)
Infectious bovine rhinotracheitis is a highly contagious respiratory disease caused by the bovine herpesvirus type 1 (BHV-1). This disease causes vast economic losses in cattle breeding, namely in dairy cattle breeds and consequently in the dairy industry. The aim of the thesis was to evaluate the process of the National IBR eradication program since its beginning to the present day. I have collected data mapping the course of five years of the NEP IBR. In the second part of the thesis I have examined six farms in the Český Krumlov region and another six farms in the Tábor region. Then I compared these two regions and evaluated the results.
4

Development of an assessment process for the evaluation of contractor performance measurement baselines

Mushrush, Christopher D. 02 February 2010 (has links)
Master of Science
5

Immediate breast reconstruction in breast cancer patients2018 at the University Hospital of Örebro

Gromelsky Ljungcrantz, Emily January 2020 (has links)
Introduction: To save lives, mastectomy is an essential intervention, but it can also causephysical and psychological trauma. An important step in restoring breast cancer patient’squality of life is to offer reconstruction. Immediate breast reconstruction (IBR) is thealternative that provides highest patient-reported life quality post surgery. However, not allpatients are suitable for the procedure, besides surgical contraindications; both patient’s andsurgeon’s opinion on surgery may influence the frequency.Data from 2016 revealed low frequency of IBR in the County of Örebro, below nationaltargets. Since then, improvement work has been implemented to improve frequency.Aim: To investigate the current frequency of IBR in 2018 and compare with data from 2016.Method: Data on mastectomy and IBR frequency in breast cancer patients was extractedfrom casebooks. Patients with male gender, neoadjuvant radiotherapy and other purposes forsurgery than cancer were excluded. Using SPSS statistics, population characteristics wascompared between IBR and mastectomy alone patients, and with data from 2016.Results: It was evident that the frequency of IBR 2018 (12.66 %) was higher than in 2016(4.85 %), which match our hypothesis. Further, there was no significant difference incharacteristics between the mastectomy alone and IBR group except for “waiting time forsurgery”, “discussion at MDK on IBR” and “age”.Conclusion: IBR surgeries have increased since 2016. Future focus to improve frequencyshould be on shortening the waiting time and addressing patient’s opinion on surgery, asseveral patients declined.
6

Fundamentals of Operation of the Induced Bed Reactor (IBR) Anaerobic Digester

Dustin, Jacob Shaun 01 May 2010 (has links)
The Induced Bed Reactor (IBR) was developed at Utah State University to apply high-rate anaerobic digestion techniques to high solids content substrates. This technology has been successfully implemented at full-scale multiple installations in the United States and Canada as a waste treatment and energy production technology, but the physical processes necessary to further optimize the system were not well understood. Bench scale IBRs were operated as anaerobic digesters at 35°, 45°, and 55° C under three organic loading rates and three corresponding hydraulic retention times. Reactor performance was monitored at steady state for residence time distribution and substrate reduction. The results show that the IBR behaves as a retained biomass reactor with fluid mixing that most closely approximates Completely Stirred Tank Reactor (CSTR) behavior when operated under the study conditions. A compartment real CSTR model, incorporating elements of dead zone and bypass flow, appears to be the most appropriate representation of the data. Mixing is likely due to a combination of energy inputs from thermal gradients induced by heat flux through the reactors and reactor and shear rates induced by gas evolution in the sludge bed.
7

Design and Dynamic Characterization of the OSU Rotor 67 Blisk for Future Damping and Mistuning Studies at Design Speed

Keener, Christopher Brady January 2021 (has links)
No description available.
8

Investigation of a testing approach for trapezoidal crest fastened metal cladding

Stephan, Hendrik Christoffel 03 1900 (has links)
Thesis (MscEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Low-rise buildings with crest fastenedmetal cladding are susceptible to failures in the vicinity of the fasteners during strongwind uplift conditions. These localised failures often lead to the progressive removal of cladding, which can cause disastrous building damage. In South Africa, the current metal cladding design approach is inadequate, since it solely relies upon manufacturer design specifications. These specifications are typically designated as broad design guidelines for the maximum allowable cladding support spacings which are independent from any specified design loads. This research focuses on the investigation of 0.50 mm ISQ550 IBR cladding systems to understand basic cladding behaviour during static wind uplift conditions and to quantify the uplift performance of IBR systems. The research investigation also included the improvement and performance evaluation of a full-scale cladding test method which applies an air-bag loading method to simulate static wind uplift conditions according to the revised SANS 10237:201X code of practice. This thesis may serve as a basis for further cladding research, and the development of suitable standardised metal cladding test methods in South Africa. Several experimental investigation methods and limited finite element analyses (FEA) were used to investigate IBR and the performance of the test methods. Tensile testing was used to determine the material properties of the cladding metal. The full-scale cladding assembly testing was used to investigate the behaviour of IBR and to evaluate the performance of the air-bag test rig. The localised behaviour of the cladding around the fasteners was also investigated with a small cladding subassembly test method. The FEA served as a supplementary investigation for IBR performance evaluation. The experimental investigation confirmed that the static wind uplift resistances of IBR systems are mainly governed by localised deformations of their fastened crests and fastener pull-through failures. The behaviour and performance of IBR systems are heavily dependent on the crest fastening arrangement. IBR systems with every crest fastening demonstrated a considerably higher wind uplift resistance than IBR systems with the standard alternate crest fastening arrangement. The measured fastener loads were independent from span length, whereas the overall uplift resistance of IBR reduced with increased span lengths. Load-span resistance data for 0.50 mm ISQ550 IBR was derived from testing to provide a rational framework for design. The FEA provided a reasonable simulation of IBR subjected to static wind uplift and confirmed the presence of high stress and strain concentrations around the fastener holes which cause fastener pull-through failures. Therefore, FEA can be used as an effective tool to investigate the behaviour of IBR. In conclusion, the air-bag test method used in this research investigation provided an effective method for evaluating the uplift performance of crest fastened metal cladding. However, the air-bag load method is not capable of accurately simulating a true uniformly distributed uplift load. It is recommended that direct air pressure testing be adopted for any further research or commercial testing ofmetal cladding because direct air pressure testing is an effective and proven test method for accurate simulation of static and cyclic wind uplift conditions. / AFRIKAANSE OPSOMMING: Metaalbekleding met kruinvashegting op lae geboue is geneig om te faal by die vashegters tydens toestande van sterkwind-opheffing. As vashegters faal kan bekleding progressief verwyderwordomrampspoedige skade aan die gebou te veroorsaak. Die huidige ontwerpmetode vir metaalbekleding in Suid-Afrika is onvoldoende, aangesien dit slegs gegrond is op vervaardigers se ontwerpspesifikasies. Spesifikasies word gewoonlik verklaar as breë ontwerpriglyne vir die maksimum toelaatbare spasiërings van ondersteunings sonder enige oorwegings vir ontwerpbelastings. Hierdie navorsing fokus dus op 0.50mm ISQ550 IBR metaalbekleding omdie basiese gedrag van bekleding tydens wind-opheffing beter te verstaan en die ophefweerstand van IBR te kwantifiseer vir ontwerpdoeleindes. Verder ondersoek hierdie navorsing ook die verbetering en evaluasie van ’n volskaalse bekledingstoetsmetode wat statiese wind-opheffing naboots met verspreide lugsakbelasting volgens die hersiende SANS 10237:201X gebruikskode. Hierdie proefskrif kan dien as ’n grondslag vir verdere navorsing en die ontwikkeling van geskikte standaard-toetsmetodes vir metaalbekleding in Suid-Afrika. Verskeie eksperimentele toetsmetodes en beperkte eindige-element-analises (EEA) is gebruik om die gedrag van IBR en die toets-opstellings te ondersoek. Trektoetse is gebruik om die meganiese eienskappe van die bekledingsmetaal te bepaal. Volskaalse toets-opstellings is gebruik om die weerstand van IBR te ondersoek en die lugsaktoetsmetode te evalueer. Die gelokaliseerde gedrag van die bekleding rondom die vashegters was ook ondersoek met klein toets-opstellings. EEA het gedien as ’n aanvullende ondersoek om die gedrag van IBR te evalueer. Die eksperimentele ondersoek het bevestig dat die wind-ophefweerstande van IBR-stelsels hoofsaaklik bepaal word deur gelokaliseerde deformasies van die vasgehegde kruine en die vashegters se deurtrekweerstand. Die gedrag en weerstand van IBR-stelsels is ook grootliks afhanklik van die toegepaste vashegtingsmetode. IBR stelsels met vashegting deur elke kruin het ’n hoër ophefweerstand verskaf as IBR-stelsels met die standaard vashegtingsmetode deur elke tweede kruin. Die gemete vashegterbelastings was onafhanklik van die spanlengtes, terwyl die algehele ophefweerstand van IBR verminder het vir langer spanlengtes. Toetsdata is gebruik om ophefweerstande vir 0.50mm ISQ550 IBR oor verskeie spanlengtes af te lei sodat ’n rasionele raamwerk vir ontwerp bewerkstellig kan word. Die EEA het die gedrag van IBR tydens toestande van statiese wind-opheffing redelik goed nageboots en het ook die teenwoordigheid van hoë spannings- en vervormingskonsentrasies rondom die vashegtergate, wat vashegters laat deurtrek, bevestig. Daarom kan EEA as ’n effektiewe instrument gebruik word om die gedrag van IBR te ondersoek. Ten slotte word dit afgelei dat die lugsaktoetsmetode van hierdie navorsingsondersoek ’n effektiewe metode verskaf het vir die gedrag-evaluering van kruinvasgehegte bekleding tydens wind-opheffing. Die lugsaktoetsmetode kan egter nie ’n ware gelykverspreide ophefbelasting naboots nie. Daarom word dit voorgestel dat toetsmetodes wat direkte lugdruk aanwend gebruik moet word vir enige verdere navorsing of kommersiële toetse van metaalbekleding, aangesien dit ’n effektiewe en bevestigde toetsmetode is wat statiese en sikliese opheftoestande akkuraat kan naboots.
9

Bildbaserad rendering : Implementation och jämförelse av två algoritmer

Härdling, Peter January 2010 (has links)
Det här arbetet har gått ut på att jämföra två algoritmer för bildbaserad rendering. Båda algoritmerna använder två bilder som spelats in med formatet MultiView plus depth för att rendera nya mellanliggande vyer av en tredimensionell scen. De tvådimensionella bilderna är kompletterade med djupvärden för varje bildpunkt. Renderingen kan då utföras genom perspektivriktiga transformationer där alla bildpunkters nya positioner projiceras individuellt. I samband med renderingen behöver bland annat mätfel i de ursprungliga bilderna samt skymda partier hanteras. Algoritm I gör det delvis genom utjämning av skarvararna mellan bildernas bidrag till den nya vyn. Algoritm II bygger på att bilderna delas upp i lager där de lager som ansetts vara säkra prioriteras framför lager som har bedömts vara mer riskabla. Algoritmerna har implementerats i Matlab och algoritm II har modifierats genom kompletteringar av dess regler för prioriteringen av lagren till mer komplicerade scener. Algoritm II har visat sig vara bättre på att bevara detaljer i de renderade vyerna och håller en jämnare hastighet vid renderingarna. Den ger även högre och jämnare resultat vid jämförelse med kvalitetsmåttet PSNR men vid jämförelser med MSSIM har den däremot fått något lägre värden. De ytterligare stegen vid renderingen har även ökat renderingstiderna med upp till 40 % jämfört med algoritm I. Författaren ger förslag på områden för fortsatt utveckling av algoritm II. Till exempel bör algoritmen testas vidare för att avgöra om de använda gränsvärdena är generella eller om de måste anpassas till olika scener. / This thesis has been aimed at comparing two algorithms for image-based renderings. Both algorithms uses two images recorded with the MultiView plus depth format, to render new intermediate views of a three-dimensional scene. The two-dimensional images extensions with depth values for each pixel, makes it possible to perform the image warping as perspective projections of all individually pixels to their new positions. During rendering, such as measurement error in the original images and occlusions has to be handled. Algorithm I is partly based on smoothening the joints between the contributions from the two images to the novel view. Algorithm II divides the images into layers, in which layers consid-ered safe has priority over layers that have been defined as more risky. The algorithms have been implemented in Matlab and algorithm II has been modified through additions to the priority rules for the layers to more complex scenes. Algorithm II has proven to be better at preserving the details in the rendered views, and maintains a less varying speed when rendering. It also provides higher and more consistent PSNR values, but in comparison using MSSIM the values are slightly lower. The additional steps have also increased the rendering times by up to 40 % compared to algorithm I. The author suggests areas for further development of algorithm II. For example, the algorithm should be tested further to determine if the used thresholds are general or whether they must be adapted to different scenes.
10

Protection and Cybersecurity of Inverter-Based Resources

Alexander, Brady Steven 14 May 2024 (has links)
Traditionally, power system protection describes detecting, clearing, and locating faults in the power system. Traditional methods for detecting and locating faults may not be sufficient for inverter-based resources (IBR) as the fault response of an IBR differs from the response of a synchronous generator. As the composition of the power grid continues to evolve to integrate more IBRs that employ communication-based control algorithms; the power system is also exposed to cyberattacks. Undetected cyberattacks can disrupt normal system operation causing local outages. Therefore, power system protection must evolve with the changes in the grid to not only detect, locate, and clear faults with IBR generation but also detect and mitigate cyberattacks on IBR controllers. This thesis proposes methods for protecting an IBR-based transmission system from: (i) GPS spoofing cyberattacks on a power sharing controller; (ii) open-circuit faults. The GPS spoofing detection algorithm is a decision tree that enables either the proposed state observer--based mitigation technique or the proposed long short-term memory (LSTM)-based mitigation algorithm. The proposed logic for detecting open-circuit faults addresses each subcategory of open-circuit faults: breaker malfunctions, broken conductors, and series arc faults. PSCAD/EMTDC simulations are performed to test the effectiveness of the proposed methods. / Master of Science / The desire to reduce carbon emissions from electric power generation is resulting in the simultaneous retirement of fossil-fuel-burning electric power generation and increase in the number of renewable energy resources. These renewable energy resources, or inverter-based resources, respond differently to disturbances than traditional generators, and; therefore, require the development of new strategies to improve the disturbance response of an inverter-based resource. Disturbances in the power system can be divided into two types: (i) normal disturbances; (ii) abnormal disturbances. The response of an IBR to normal disturbances is improved with reliable control, further improved with communication, which ensures the stable operation of the power system. The abnormal conditions can also be split into two categories: (i) cyberattacks; (ii) faults. A cyberattack is when an adversary gains access a system with the goal of causing harm. In IBRs, cyberattacks can degrade power quality and lead to local outages. Faults are events that cause a change in the normal current flow in the power system. Undetected faults can cause local outages, lead to forest fires, and personnel injury; therefore, must be detected, located, can cleared in a timely manner. This work explores methods for detecting and mitigating cyberattacks and detecting faults in the presence of inverter-based resources.

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