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Milica, Samardžić. "Vremensko i prostorno rasprostranjivanje zagađivača u slivu Velike Morave." Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2013. http://dx.doi.org/504.5(043.3).
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Na osnovu podataka o hidrološkim i parametrima kvaliteta sa 28 mernih profila u slivuVelike, Južne i Zapadne Morave od 2000. do 2009. godine, u radu je analizirano prostorno ivremensko rasprostranjivanje zagađujućih materija duž analiziranih vodotoka, kao i uticajpoznatih izvora zagađenja na kvalitet vode u vodotocima. U cilju ocene mogućnostipredviđanja vrednosti nekih od parametara kvaliteta u analiziranim vodotocima, statističkomanalizom obuhvaćeni su podaci sa 5 mernih profila, za koje su postavljeni modeli regresioneanalize za predikciju sadržaja rastvorenog kiseonika, koncentracije suspendovanih materija,koncentracije orto-fosfata, vrednosti HPK i vrednosti BPK5, a na osnovu vrednosti proticaja ivremenske komponente – meseca u godini u kome je vršeno merenje.On the basis of data on hydrological and water quality parameters from 28 measure points inthe river basins of Velika Morava, Južna Morava and Zapadna Morava, during ten yearsperiod from 2000. to 2009., this work analyzes spatial and temporal dispersal of pollutantsalong the observed watercourses, as well as the effect of known sources of pollution to thewater quality. In order to estimate the possibility for predicting of some water qualityparameters (concentration of dissolved oxygen, concentration of suspended matters,concentration of o-phosphates, COD and BOD5) values, based on value of flow and timecomponent (month of the year in which the measurement was performed), for 7 measurepoints there are defined statistical regression models.
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Ross, Martin James. "Investigation into Catalytic Metallodrugs that Target Hepatitis C IRES RNA: Development, Characterization, and Mechanism." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440421045.
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Prokopetc, Kristina. "Precise Mapping for Retinal Photocoagulation in SLIM (Slit-Lamp Image Mosaicing)." Thesis, Université Clermont Auvergne (2017-2020), 2017. http://www.theses.fr/2017CLFAC093/document.
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Cette thèse est issue d’un accord CIFRE entre le groupe de recherche EnCoV de l’Université Clermont Auvergne et la société Quantel Medical (www.quantel-medical.fr). Quantel Medical est une entreprise spécialisée dans le développement innovant des ultrasons et des produits laser en ophtalmologie. Cette thèse présente un travail de recherche visant à l’application du diagnostic assisté par ordinateur et du traitement des maladies de la rétine avec une utilisation du prototype industriel TrackScan développé par Quantel Medical. Plus précisément, elle contribue au problème du mosaicing précis de l’image de la lampe à fente (SLIM) et du recalage automatique et multimodal en utilisant les images SLIM avec l’angiographie par fluorescence (FA) pour aider à la photo coagulation pan-rétienne naviguée. Nous abordons trois problèmes différents.Le premier problème est lié à l’accumulation des erreurs du recalage en SLIM., il dérive de la mosaïque. Une approche commune pour obtenir la mosaïque consiste à calculer des transformations uniquement entre les images temporellement consécutives dans une séquence, puis à les combiner pour obtenir la transformation entre les vues non consécutives temporellement. Les nombreux algorithmes existants suivent cette approche. Malgré le faible coût de calcul et la simplicité de cette méthode, en raison de sa nature de ‘chaînage’, les erreurs d’alignement s’accumulent, ce qui entraîne une dérive des images dans la mosaïque. Nous proposons donc d’utilise les récents progrès réalisés dans les méthodes d’ajustement de faisceau et de présenter un cadre de réduction de la dérive spécialement conçu pour SLIM. Nous présentons aussi une nouvelle procédure de raffinement local.Deuxièmement, nous abordons le problème induit par divers types d’artefacts communs á l’imagerie SLIM. Ceus-sont liés à la lumière utilisée, qui dégrade considérablement la qualité géométrique et photométrique de la mosaïque. Les solutions existantes permettent de faire face aux blouissements forts qui corrompent entièrement le rendu de la rétine dans l’image tout en laissant de côté la correction des reflets spéculaires semi-transparents et reflets des lentilles. Cela introduit des images fantômes et des pertes d’information. En outre, les méthodes génériques ne produisent pas de résultats satisfaisants dans SLIM. Par conséquent, nous proposons une meilleure alternative en concevant une méthode basée sur une technique rapide en utilisant une seule image pour éliminer les éblouissements et la notion de feux spéculaires semi-transparents en utilisant les indications de mouvement pour la correction intelligente de reflet de lentille.Finalement, nous résolvons le problème du recalage multimodal automatique avec SLIM. Il existe une quantité importante de travaux sur le recalage multimodal de diverses modalités d’image rétinienne. Cependant, la majorité des méthodes existantes nécessitent une détection de points clés dans les deux modalités d’image, ce qui est une tâche très difficile. Dans le cas de SLIM et FA ils ne tiennent pas compte du recalage précis dans la zone maculaire - le repère prioritaire. En outre, personne n’a développé une solution entièrement automatique pour SLIM et FA. Dans cette thèse, nous proposons la première méthode capable de recolu ces deux modalités sans une saisie manuelle, en détectant les repères anatomiques uniquement sur une seule image pour assurer un recalage précis dans la zone maculaire. (...)This thesis arises from an agreement Convention Industrielle de Formation par la REcherche (CIFRE) between the Endoscopy and Computer Vision (EnCoV) research group at Université Clermont Auvergne and the company Quantel Medical (www.quantel-medical.fr), which specializes in the development of innovative ultrasound and laser products in ophthalmology. It presents a research work directed at the application of computer-aided diagnosis and treatment of retinal diseases with a use of the TrackScan industrial prototype developed at Quantel Medical. More specifically, it contributes to the problem of precise Slit-Lamp Image Mosaicing (SLIM) and automatic multi-modal registration of SLIM with Fluorescein Angiography (FA) to assist navigated pan-retinal photocoagulation. We address three different problems.The first is a problem of accumulated registration errors in SLIM, namely the mosaicing drift.A common approach to image mosaicking is to compute transformations only between temporally consecutive images in a sequence and then to combine them to obtain the transformation between non-temporally consecutive views. Many existing algorithms follow this approach. Despite the low computational cost and the simplicity of such methods, due to its ‘chaining’ nature, alignment errors tend to accumulate, causing images to drift in the mosaic. We propose to use recent advances in key-frame Bundle Adjustment methods and present a drift reduction framework that is specifically designed for SLIM. We also introduce a new local refinement procedure.Secondly, we tackle the problem of various types of light-related imaging artifacts common in SLIM, which significantly degrade the geometric and photometric quality of the mosaic. Existing solutions manage to deal with strong glares which corrupt the retinal content entirely while leaving aside the correction of semi-transparent specular highlights and lens flare. This introduces ghosting and information loss. Moreover, related generic methods do not produce satisfactory results in SLIM. Therefore, we propose a better alternative by designing a method based on a fast single-image technique to remove glares and the notion of the type of semi-transparent specular highlights and motion cues for intelligent correction of lens flare.Finally, we solve the problem of automatic multi-modal registration of FA and SLIM. There exist a number of related works on multi-modal registration of various retinal image modalities. However, the majority of existing methods require a detection of feature points in both image modalities. This is a very difficult task for SLIM and FA. These methods do not account for the accurate registration in macula area - the priority landmark. Moreover, none has developed a fully automatic solution for SLIM and FA. In this thesis, we propose the first method that is able to register these two modalities without manual input by detecting retinal features only on one image and ensures an accurate registration in the macula area.The description of the extensive experiments that were used to demonstrate the effectiveness of each of the proposed methods is also provided. Our results show that (i) using our new local refinement procedure for drift reduction significantly ameliorates the to drift reduction allowing us to achieve an improvement in precision over the current solution employed in the TrackScan; (ii) the proposed methodology for correction of light-related artifacts exhibits a good efficiency, significantly outperforming related works in SLIM; and (iii) despite our solution for multi-modal registration builds on existing methods, with the various specific modifications made, it is fully automatic, effective and improves the baseline registration method currently used on the TrackScan
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Sentmanat, Martin Lamar. "Design and evaluation of a slit die rheometer to study wall slip." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61100.
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Extrudate distortion is a problem that often limits production rates in certain commercial processes such as film blowing and it has been suggested that slip in the die land plays an important role in this phenomena. It has been hypothesized that during slip flow in a die neither the wall shear stress nor the slip velocity is constant along the length of the die. For this reason, a slit die rheometer was developed to monitor directly the shear stress distribution of a molten polyethylene by means of two shear stress transducers mounted at different axial locations along the length of the slit. Previous transducers used at McGill do not perform well at high pressures. Therefore, a new disk-bar shear stress transducer was designed for use at high pressure. However, experimental evaluation of the slit die rheometer suggests that the large pressure gradient present in the slit affects the operation of this transducer. It is hypothesized that the pressure gradient across the active face of the shear stress transducer and the disk element impose a torque opposite to that of the applied shear stress on the active face. This pressure gradient effect was unanticipated because no shear stress transducer has ever been used in a pressure driven flow. Before the research on wall slip can proceed a new shear stress transducer that is unaffected by either high pressure or large pressure gradients must be developed. Possible ways of meeting this need are proposed.
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Lazar, Lazić. "Tamiš i vodoprivredni problemi Potamišja u Jugoslaviji." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 1996. https://www.cris.uns.ac.rs/record.jsf?recordId=114389&source=NDLTD&language=en.
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Prvim delom rada su obuhvaćene opšte karakteristike sliva Tamiša i njegovog toka. Tamiš u našoj zemlji ima sve karakteristike ravničarske reke. Izvire ispod vrha Semenik u Rumuniji, a ušće mu se nalazi kod Pančeva. Generalno tok Tamiša ima oblik polukruga okrenutog ka severu. Ukupna dužina Tamiša iznosi 340 km, dok u našoj zemlji on ima dužinu od 118 km. Sliv Tamiša u Jugoslaviji obuhvata delove srednjeg i južnog Banata, a prostire se preko 7 geomorfoloških celina, na površini od 1528,5 km2. Posle obrade režima vodostaja se može konstatovati da Tamiš ima pojavu visokih voda u aprilu, a zatim u maju, a najnižih u oktobru i septembru. Prema tome on pripada centralno-evropskoj varijanti, pluvio-nivalnog režima. Drugi deo ovog rada je posvećen vodoprivrednim karakteristikama i problemima Potamišja. Ono u celini ima površinu od 1.194,7 km2, sa 121.596 stanovnika (popis 1991). Na ovom području nalazimo 20 naselja, od kojih samo Pančevo ima karakter gradskog naselja. Bitne karakteristike Potamišja se sastoje u njegovom depopulacionom karakteru i slaboj privrednoj razvijenosti sa dominacijom agrara. Ovaj prostor se odlikuje izvođenjem kompleksnih regulacionih radova tokom poslednjih 250 godina. Regulacije su obavile korenite promene u hidrogeografiji i geografskom pejzažu Potamišja. Pomenimo samo neke: skraćivanje toka Tamiša u Jugoslaviji za 79 km, prokopavanje Karašca, izgradnja 3 ustave na Tamišu i 1 na Karašcu i dr. Na području Potamišja se nalazi 18 sistema za odvodnjavanje, čija ukupna površina iznosi skoro 1000 km2 i 10 sistema za navodnjavanje površine od 4.340 ha. Potamišje se može nazvati "ribljim eldoradom". Uz postojanje 7 ribnjaka, planirana je njihova izgradnja na još 16 lokacija. Ova privredna grana mogla bi imati značajnu ulogu u popravljanju lošeg privrednog stanja ovog područja. Potamišje ima relativno bogate turističke potencijale, koji još nisu iskorišćeni. Postojeći motivi bi se najbolje ogledali u razvoju nautičkog, ribolovnog i rekreacionog turizma. Važno je napomenuti da bi razvoj turizma podstakao i razvoj drugih privrednih grana.The abstract has been processed with OCR optical text recognition technology.In the first part of dissertation there is general characteristics of Tamiš basin and his flow. In Yugoslavia Tamiš river has the all characteristic of the rivers in the plains. The spring of Tamiš river is under top of Semenic in Romania and its mouth of river is near Pančevo. In generally, flow of Tamiš has a shape of semicircle turn to north. Whole length of Tamiš river is 340 km, while in Yugoslavia its length amount 118 km.Tamiš basin in Yugoslavia include parts of middle and south Banat, spreading over 7 geomorphologic entity on the surface area of 1528,5 km2.After investigation of waterlevel regime it could be conclude that Tamiš river has the appearance of high level water in April and May, until the low level water has the appearance in October and September. Toward this, Tamiš river belong to the central-European variant of pluvio-nival regime.The second part is turn to watereconomy characteristic and problems of Potamišje region. Potamišje has the total square area of 1.194,7 km2, with 121.596 habitants (census 1991). There is 20 settlements, from which, only Pančevo has character of town. Important characteristic of Potamišje region is his depopulation character and weak development of economy with domination of agrar.Distinction of Potamišje region is complex regulations in the last 250 years. Regulations were done significant changes on hydrogeography and geographical landscape of Potamišje. Let mention some of: shortened of the Tamiš flow for 79 km, digged out the canal Karašac, built three dams on Tamiš river, and one on Karašac.In this region there are 18 system for drainage, which total square area amount almost 1.000 km2 and 10 system for irrigation with square area of 4.340 ha.The other name for Potamišje can be "fish eldorado". There are 7 fish-pond, and on the other 16 location were planed there build.Potamišje has, relatively, rich tourists potentials, which are not developed. Existing motives are appropriate for developing of nautic, fishing and recreation tourism.
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Saša, Petrović. "Karakterizacija kompozitnih nosioca flekso štamparskih formi i njihov uticaj na kvalitet štampe kartonske ambalaže." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=115003&source=NDLTD&language=en.
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U disertaciji je izvršena karakterizacija sliv nosioca fleksoštamparskih formi i predstavljena su istraživanja uticaja promenemehaničkih i adhezivnih svojstava slivova na parametre kvalitetaštampe kartonske ambalaže. Korišćene su dve grupe samolepljivihslivova (potpuno novi i slivovi korišćeni za štampu 5.000.000 mmaterijala). Ciljevi istraživanja su povećanje predvidivosti ikonstantnosti kvaliteta štampanog proizvoda i procesa proizvodnjekartonske ambalaže, formiranje preporuka za upotrebu slivovarazličitih svojstava i nivoa eksploatisanosti i otkrivanje u kojimfazama i kojim procesima dolazi do promena svojstava slivova.Research presented in this dissertation includes characterization offlexographic sleeves and the study of the influence of the changes inmechanical and adhesive properties of the sleeves on print qualityparameters of the cardboard packaging. Two groups of self-adhesive sleeveswere used (entirely new and sleeves used for printing of 5.000.000 m ofmaterial). Aims of the research are the increase in predictability and stabilityof the printed product quality and the production process of cardboardpackaging, forming of the recommendations for the use of sleeves withdifferent properties and levels of exploitation, as well as defining the phasesand processes responsible for the changes in sleeve properties.
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Ratko, Bajčetić. "Идентификација доминантних учесника у партиципативном моделу одлучивања у водопривреди." Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=101333&source=NDLTD&language=en.
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Сложеност процеса доношења одлука у водопривреди лежи у чињеници да су проблеми који се решавају често слабо структурирани, због чега је неопходно њихово учвршћивање хеуристичким техникама до нивоа када се проблем може решити применом математичких модела вишекритеријумске оптимизације и анализе.Групно доношење одлука у водопривреди није новост у свету, али коначнаг одређења методологије у овој области још увек нема. Постојање конфликата између различитих страна, заинтересованих за проблематику водопривреде, између врста коришћења вода, као и самих корисника вода указује на сложеност проблемтике. Сложеност увећава постојање великог броја алтернатива, које треба вредновати према великом броју критеријума.Методологија избора учесника у доношењу одлука у водопривреди и одређивања њихових међусобних значаја, који је предложена у дисертацији, заснована је на коришћењу техника стратегијског менаџмента, прогностичких метода, гласачких метода, метода вишекритеријумске анализе и оптимизације и ГИС технологијама.Досадашњи систем управљања водним ресурсима у Србији има слабости јер није у довољној мери заснован на корисничким захтевима, а свака промена захтева обично доводи до дуготрајне процедуре за измену статуса корисника, или измену квалитативних и квантитативних захтева у односу на водне ресурсе.Развијени партиципативни модел, који подрзумева дефинисање конзистентног поступка за избор учесника у процесу управљања сливом, као и одређивање њихових међусобних односа и значаја, у садашњим условима и условима пуне изграђености Регионалног хидросистема демонстриран је на примеру слива реке Криваје.Слив Криваје одабран је због вишеструке сложености водопривредне проблематике, јер је вишенаменски, вишекориснички, са поделама надлежности, како локалних самоуправа, тако и водопривредне делатности. Такође, Криваја је прекогранични водоток, што проблематику усложњава и у међудржавном, ресурсном, економском и политичком смислу. Методологија приказана у дисертацији примењива је и на друге сливове, 'оптерећене' вишенаманским, вишекорисничким конфликтима, као и конфликтима надлежности.Основна карактеристика модела је конзистентна структуираност, модул консензусног одлучивања у конфликтним и хазардним условима и употреба савремених математичко-компјутерских метода и модела и информационих технологија који, поред осталог, синергијски указују на доминантне учеснике у процесу одлучивања.Složenost procesa donošenja odluka u vodoprivredi leži u činjenici da su problemi koji se rešavaju često slabo strukturirani, zbog čega je neophodno njihovo učvršćivanje heurističkim tehnikama do nivoa kada se problem može rešiti primenom matematičkih modela višekriterijumske optimizacije i analize.Grupno donošenje odluka u vodoprivredi nije novost u svetu, ali konačnag određenja metodologije u ovoj oblasti još uvek nema. Postojanje konflikata između različitih strana, zainteresovanih za problematiku vodoprivrede, između vrsta korišćenja voda, kao i samih korisnika voda ukazuje na složenost problemtike. Složenost uvećava postojanje velikog broja alternativa, koje treba vrednovati prema velikom broju kriterijuma.Metodologija izbora učesnika u donošenju odluka u vodoprivredi i određivanja njihovih međusobnih značaja, koji je predložena u disertaciji, zasnovana je na korišćenju tehnika strategijskog menadžmenta, prognostičkih metoda, glasačkih metoda, metoda višekriterijumske analize i optimizacije i GIS tehnologijama.Dosadašnji sistem upravljanja vodnim resursima u Srbiji ima slabosti jer nije u dovoljnoj meri zasnovan na korisničkim zahtevima, a svaka promena zahteva obično dovodi do dugotrajne procedure za izmenu statusa korisnika, ili izmenu kvalitativnih i kvantitativnih zahteva u odnosu na vodne resurse.Razvijeni participativni model, koji podrzumeva definisanje konzistentnog postupka za izbor učesnika u procesu upravljanja slivom, kao i određivanje njihovih međusobnih odnosa i značaja, u sadašnjim uslovima i uslovima pune izgrađenosti Regionalnog hidrosistema demonstriran je na primeru sliva reke Krivaje.Sliv Krivaje odabran je zbog višestruke složenosti vodoprivredne problematike, jer je višenamenski, višekorisnički, sa podelama nadležnosti, kako lokalnih samouprava, tako i vodoprivredne delatnosti. Takođe, Krivaja je prekogranični vodotok, što problematiku usložnjava i u međudržavnom, resursnom, ekonomskom i političkom smislu. Metodologija prikazana u disertaciji primenjiva je i na druge slivove, 'opterećene' višenamanskim, višekorisničkim konfliktima, kao i konfliktima nadležnosti.Osnovna karakteristika modela je konzistentna struktuiranost, modul konsenzusnog odlučivanja u konfliktnim i hazardnim uslovima i upotreba savremenih matematičko-kompjuterskih metoda i modela i informacionih tehnologija koji, pored ostalog, sinergijski ukazuju na dominantne učesnike u procesu odlučivanja.
The complexity of the decision-making process in water management lies in the fact that problems, to be solved, are often poorly structured, making it necessary to strenghten them by heuristic techniques to the level where problem can be solved by using mathematical models of multi-criteria optimization and analysis.Group decision-making in water management is not unknown, but the final determination of methodology in this area is still missing.The existence of conflicts between the various parties interested in the issue of water management, between a type of water use and water users themselves, indicates the complexity of the problems. The complexity increases the presence of a large number of alternatives that must be evaluated against a number of criteria.The methodology of selection of participants in decision-making in water management and determining their mutual importance; importance of each one among the others; importance of each of them among the group; importance of each of participants, which is presented in the dissertation, is based on the use of techniques of strategic management, forecasting methods, the voting methods, multi-criteria analysis and optimization, and GIS technologies.The current system of water resources management in Serbia has a weakness because it is not sufficiently based on user requirements, and any requirement’s change usually leads to time-consuming procedures for changing the status of users, or alteration of qualitative and quantitative requirements in relation to water resources.Developed participatory model, which implies defining a consistent procedure for the selection of participants in the river basin management, as well as determining their relationships and importance in current terms and conditions of the full construction of the Regional hydro system, has been demonstrated on the example of the basin of the Krivaja river.Confluence Krivaja has been chosen because of multiple complexities of water management issues, its multipurpose, multi-user, the division of responsibilities among local self-governments, as well as water management work. Also, Krivaja is cross-border watercourse, which complicates the issue in the interstate, resource, economic and political sense. The methodology presented in the dissertation is also applicable to other basins 'loaded' by multipurpose and multi-user conflicts, as well as conflicts of jurisdiction.The basic characteristic of the model is consistent structure, the module of consensual decision-making in conflict and hazardous conditions, and the use of modern mathematical-computerized methods and models, as well as information technologies which, among other things, the synergistic indicate the dominant participants in the decision-making process.
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Vodička, Radek. "Rozpoznávání izolovaných slov." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220658.
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Main purpose of the thesis is to study the processes and methods of isolated words recognition. In the theoretical part a basic principals are explained. The practical part is about the program creating using these principles in practice. For isolated words recognition Hidden Markov Models (HMM) are used, for obtaining decision symptoms cepstral analysis is chosen.
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Wiedeman, Christopher William. "The Carnal Slip." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd_retro/167.
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The thesis exhibit installed at VCU's Anderson Gallery was carried out using still imagery (a photograph), moving imagery (recorded video, live video), constructed objects and a delineated space. It was an experiment dealing with how one comes to know the world by virtue of one's physical activity within it. It was most importantly a work that required the viewer's participation in order to become "complete".
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Fortier, Alicia Elena. "Numerical Simulation of Hydrodynamic Bearings with Engineered Slip/No-Slip Surfaces." Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4929.
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The no-slip boundary condition is the foundation of traditional lubrication theory. It says that fluid adjacent to a solid boundary has zero velocity relative to that solid surface. For most practical applications the no-slip boundary condition is a good model for predicting fluid behavior. However, recent experimental research has found that for special engineered surfaces the no-slip boundary condition is not applicable. Measured velocity profiles suggest that slip is occurring at the interface. In the present study, it is found that judicious application of slip to a bearings surface can lead to improved bearing performance.
The focus of this thesis is to analyze the effect an engineered slip/no-slip surface could have on hydrodynamic bearing performance. A heterogeneous pattern is applied to the bearing surface in which slip occurs in certain regions and is absent in others. Analysis is performed numerically for both plane pad slider bearings and journal bearings. The performance parameters evaluated for the bearings are load carrying capacity, side leakage rate and friction force. Fluid slip is assumed to occur according to the Navier relation and the effect of a critical value for slip onset is considered.
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Kaneda, Heitaro. "Detection of Active Low Slip-Rate Strike-Slip Faults and Their Paleoseismicity." 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/147787.
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Smith, Elizabeth Therese. "Slip table dynamic behavior." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/49941.
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Hack, Thorsten. "Stick-slip piezoelectric actuators." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624403.
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Møller, Christian Nicolai. "Scanning slit 3D displays." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613824.
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Jadrníček, Zbyněk. "Shlukování slov podle významu." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2015. http://www.nusl.cz/ntk/nusl-234899.
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This thesis is focused on the problem of semantic similarity of words in English language. At first reader is informed about theory of word sense clustering, then there are described chosen methods and tools related to the topic. In the practical part we design and implement system for determining semantic similarity using Word2Vec tool, particularly we focus on biomedical texts of MEDLINE database. At the end of the thesis we discuss reached results and give some ideas to improve the system.
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Strachota, Tomáš. "Automatické navrhování klíčových slov." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-237243.
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This thesis surveys theoretical background for automatic keyword suggestion system. It contains overview of current statistical term recognition methods and methods for evaluation of automatic term recognition systems. Based on the known approach the thesis specifies possible enhancements. It explores unifying keywords using thesauri, input text filtering and correction of word forms.
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Vacek, Matěj. "Pragmatický lematizátor českých slov." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-192440.
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This thesis is focused on lemmatizing of nouns and adjectives. It is based on morphology of Czech language. The goal is to create a lemmatizer which can stem words with success rate 90% (at least). At the same time the lemmatizer should be very easy, it should consist as little rules as possible. Lemmatizer will be created to work with real estate adverts, especially houses for sale. In this thesis there will be made an analysis of specific characters of this area. Lemmatizer will be created according to results of this analysis. Lemmatizer was written in Java. Only three types of rules were used and generally the lemmatizer created correct stems in 96.4% of all words.
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Xu, Guoda, John M. Bartha, Stuart McNamee, Larry Rheaume, and Allen Khosrowabadi. "OPTICAL SLIP-RING CONNECTOR." International Foundation for Telemetering, 1999. http://hdl.handle.net/10150/607336.
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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, NevadaCurrent ground-based tracking systems at the DoD test and training ranges require transmission of a variety of signals from rotating platform to fixed control and process center. Implementation of commercial off the shelf (COTS) solution for transmitting high-speed, multiple-channel data signals over a rotational platform prompt the development of an advanced electro-optic hybrid rotating-to-fixed information transmission technology. Based on current demand, an Air Force-sponsored Small Business Innovative Research (SBIR) contract has been awarded to Physical Optics Corporation (POC) to modify existing tracking mounts with a unique electro-optic hybrid rotary joint (EOHRJ). The EOHRJ under current development is expected to provide the following features: 1) include a specially designed electrical slip-ring, which is able to accommodate hundreds of transmission channels, including electrical power, control, feedback, and low-speed data signals; 2) include an optical fiber slip-ring which, by incorporating with electrical time division mulitplexing (TDM) and optical wavelength division multiplexing (WDM) technologies, is able to provide multiple channel, high data rate (over gigabits per second), and bi-directional signal transmission; and 3) is designed to be reliable for harsh environmental operation, adaptive to stringent size requirement, and accommodating to existing electrical and mechanical interfaces. Besides the military use, other possible commercial applications include on board monitoring of satellite spinners, surveillance systems, instrumentation and multi spectral vision systems, emergency/medical instruments, remote sensing, and robotics.
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Mak, Hong-man Herman, and 麥匡文. "Effective slip due to Stokes flow through channels with patterned stick-slip walls." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B47153970.
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This thesis comprises studies of two problems on Stokes flows through (i) a plane microchannel, and (ii) a microscale circular capillary tube, of which the walls are superhydrophobic surfaces featuring micro- or nano-patterns. In the first problem, an analytical study on longitudinal and transverse flows through a plane microchannel, which is made up of a periodic array of ribs and grooves on the upper and lower walls, is performed. This study focuses not only on the Cassie state, but also on the state whereby the liquid is allowed to penetrate the grooves between the ribs. These grooves are filled with inviscid gas and this periodic array gives rise to heterogeneous boundary conditions for the flow. Partial-slip and shear-free conditions are applied on the solid–liquid interface and the liquid–gas interface, respectively. Using the methods of eigenfunction expansions and domain decomposition, semi-analytical models are developed for four different settings. Two of them correspond to longitudinal flow with in-phase and 180-out-of-phase alignments of ribs between the upper and lower walls. The other two are for transverse flow with the in-phase and out-of-phase wall alignments. These models enable the effective slip lengths, normalized by half the pitch of the pattern, to be deduced as functions of the channel height, the microscopic or intrinsic partial slip length, the depth of liquid penetration, and the width of the grooves or the shear-free area fraction of the liquid-gas interface. Numerical calculations are performed to examine effects of these parameters on the effective slip length. The effect of the phase of alignment of ribs is appreciable when the surface is in the Cassie state and the channel height is sufficiently small. In-phase alignment yields a larger effective slip length in longitudinal flow. In sharp contrast, out-of-phase alignment is preferable in transverse flow. In the case involving penetration, a larger liquid penetration can give rise to a larger slip length in a thin channel.
In the second problem, an analytical study on flow through a microscale circular tube, of which the wall is patterned with a periodic array of spots or holes, is performed. Void region is filled with inviscid gas and patterns of circular and square shapes are considered. For simplicity, liquid penetration into the cavities is not considered, and hence the focus is on the Cassie state. No-slip and shear-free conditions are applied on the solid–liquid interface and the liquid–gas interface, respectively. By the methods of eigenfunction expansions and point collocation, a semi-analytical model is established. The effective slip length, normalized by the tube radius, is found as a function of the pitch of the pattern in the streamwise direction, the number of periodic units in the circumferential direction, and the solid fraction. Comparisons with some proposed scaling laws, varying pitch, solid fraction and tube size are performed. Large slip length is produced by arranging small circular no-slip spots with large separation in the streamwise direction. In some situations, spots and holes can be replaced by parallel stripes to increase the slip length.published_or_final_version
Mechanical Engineering
Master
Master of Philosophy
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Amey, Ruth Mary Joy. "The fractal nature of fault slip and its incorporation into earthquake slip inversions." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/22137/.
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In order to understand how earthquakes nucleate, propagate and terminate it is essential to understand the properties and stress conditions of the surfaces upon which earthquakes occur. Fault surfaces control frictional properties and by measuring exhumed faults we can better understand earthquake propagation and how this may be linked to fault structure. In order to forecast areas of a fault likely to be at risk from future failure it is necessary to accurately model the slip that occurs during each measured earthquake. In recent years many lines of evidence suggest that fault surfaces and earthquake slip show fractal properties. This includes high resolution scans of fault surfaces, observations of coseismic surface slip and analysis of published slip distributions. In this thesis I investigate how fault structure may affect the fractal properties of fault surface roughness, by investigating the along-strike changes in properties of the Campo Felice fault in the Italian Apennines. I then incorporate observations of fractal properties into earthquake slip inversions through a new form of regularisation, which I develop using Bayesian methods. Through this I aim to improve our understanding of the surfaces upon which earthquakes occur, how this links to fault structure and to improve our coseismic slip models, that provide the basis of stress models and hazard analysis. Fault surfaces displaying fractal properties mean that there is a power-law relationship between the topography of a fault and the wavelength of this topography: the magnitude of height fluctuations depends upon the scale at which they are observed. Whilst many studies have investigated fault roughness properties, here I present the first study of how fault roughness varies along the strike of a fault. I use terrestrial laser scans and laser profilometer scans at 14 locations along the length of the Campo Felice normal fault in the Italian Apennines, as well as a scan encompassing several hundred meters along the length of the fault. These scans show that the Campo Felice fault displays fractal properties over at least six orders of magnitude perpendicular to slip and at least three orders of magnitude parallel to slip. But, contrary to previous findings on other faults, I find that the Hurst parameter, which controls the fractal nature of the fault surface, changes considerably and unpredictably along the length of the fault, even between observations tens of metres apart. I suggest that this variability may be due to the variation of slip vector along the length of the fault, as is frequently observed in earthquakes. This variability could, additionally, be linked to fault asperities halting or impeding rupture, such that some areas of the fault experience more earthquakes, or experience different stress conditions during the same earthquake. I also find that the magnitude of topography displayed by Campo Felice fault is low compared to previous studies, suggesting it may be at risk of larger earthquakes. Observations of fractal fault surfaces suggest that earthquake slip should be fractal too. By using geodetic data taken at the surface before and after an earthquake we can perform slip inversions to give a model of how much slip occurred underground, on the fault surface. This is routinely performed for large, continental earthquakes. Due to noise and lack of data these inversions are frequently regularised to produce a stable solution, but the standard regularisation techniques have little physical basis. I incorporate fractal properties of earthquake slip into slip inversions by introducing a new regularisation technique: von Karman regularisation. I use a Bayesian method to fully explore parameter space and better understand uncertainties on the model parameters. From synthetic tests I find that this regularisation performs comparably, if not better, than other frequently used methods upon both fractal and Laplacian input slip distributions. Using InSAR (Interferometric Synthetic Aperture Radar) and GPS (Global Positioning System) data from the 2014 Mw 6.0 Napa Valley earthquake, I invert for slip using a two-segment fault model. I find that the choice of regularisation changes the location and magnitude of slip, which could have important implications for stress transfer and our understanding of the so-called shallow slip deficit. Through its incorporation of fractal properties, von Karman regularisation represents a more physical regularisation of earthquake slip along a fault plane. However, some bias can be introduced by incorrectly choosing the length and width of the fault plane. If a fault plane is too large, the regularisation can cause slip smearing, particularly at depth where the model is poorly constrained by the data, in order to improve the von Karman probability. To eliminate this bias I modify my Bayesian inversion scheme to solve for the size of the fault plane during the inversion, along with slip, rake and a hyperparameter controlling slip variance. This makes the inversion trans-dimensional, and aims to reduce the bias caused by an incorrect model. I apply it to the Mw 6.2 Central Tottori earthquake, Japan, using InSAR and GNSS (Global Navigation Satellite System) data. My model shows that the earthquake ruptured most of the seismogenic zone, in contrast to seismological studies. My results in this thesis further confirm that fault surface roughness shows fractal properties, and that fault structure may play an important role in the exact relationship between fault topography and the lengthscale of observation. Further investigation of exhumed fault surfaces can help inform earthquake models, including earthquake slip inversions, particularly if an earthquake were to occur on a fault upon which surface roughness measurements had already been taken. By incorporating observed fractal properties into earthquake slip inversions I aim to introduce less bias than other, less physical regularisations. With the European Space Agency's new satellites Sentinel-1a/b providing regular observations of the Earth's deforming regions, we are in a position to model earthquake slip better than ever before. I hope that by incorporating more realistic observations and using Bayesian methods to fully understand uncertainties, we can produce better, more realistic models. These models help our understanding of earthquakes, and, most importantly, earthquake hazard.
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Boutareaud, Sébastien. "Slip-weakening mechanisms at high slip-velocities : insights from analogue and numerical modellings." Besançon, 2007. http://www.theses.fr/2007BESA2030.
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Cette thèse vise à étudier les propriétés thermo-poro-mécaniques de roches de faille, à partir de l’analyse structurale et microstructurale d’une faille aujourd’hui à l’affleurement et à partir d’expériences menées en laboratoire, en vue de déterminer les processus qui contrôlent l'efficacité de deux mécanismes responsables de d’affaiblissement cosismiques : la pressurisation thermique et le mécanisme d’affaiblissement par drainage. L'étude de terrain a été conduite sur deux affleurements appartenant à une faille décrochante potentiellement active appartenant au système de failles du Chugoku occidental (Japon) : la faille d’Usukidani. Le travail expérimental a quant à lui été mené dans le laboratoire de déformation des roches de l'Université de Kyoto. Les résultats majeurs de ce travail sont exposés ci- dessousThis thesis aims at studying the thermo-poro-mechanical properties of fault rock materials by means of field analysis of an exhumed fault and laboratory experiments, in order to determine the processes responsible of the efficiency of two thermally-activated slip-weakening mechanisms: the thermal pressurization and the moisture-drained weakening mechanism. The field study was conducted on well-exposed outcrops of a potentially active strike-slip fault that belongs to the Western Chugoku fault system (Japan): the Usukidani fault. The experimental work was conducted in the rock deformation laboratory at Kyoto University. The primary results of this research are exposed below
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Saxena, Pawan. "Slip casting of silicon nitride." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=56974.
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Slip casting is a well established technique for the manufacture of traditional ceramic bodies, such as clays and whitewares. It combines complex shaping with high green densities, resulting in low shrinkage and good densification behaviour.This method, however, has received little attention in the field of engineering ceramics especially with regard to silicon nitride. Commercial fabrication of silicon nitride, a major contender for high temperature applications due to its excellent thermomechanical properties, has been confined to hot pressing. This is an expensive process and has geometrical limitations.
Slip casting, followed by sintering, has been identified as a potentially economical alternative fabrication method, however a number of parameters have to be optimized before a good slip cast silicon nitride body can be made. The aim of the present work is to control parameters such as pH, viscosity and deflocculation in order to form dense, homogeneous, slip cast silicon nitride bodies.
A detailed investigation of the rheological properties of Si$ sb3$N$ sb4$ and careful control of processing parameters, made it possible to produce slip cast Si$ sb3$N$ sb4$ bodies having up to 97% TD on sintering. Mechanical strength values obtained by slip casting were compared with those obtained by die-pressing. Strength values of the slip cast material was limited by iron inclusions entrained in processing.
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Sander, R. "Modelling of slit die extrusion." Thesis, Swansea University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638761.
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The present work is concerned with the investigation of the slit die extrusion of molten polymers, and a systematic strategy is developed for the modelling of its major aspects. The objective is to provide a fundamental understanding of the flow phenomena within such a die, coupled with thermal and mechanical interaction of melt and die body, and to provide user friendly software for analysis and design. Isothermal, non-Newtonian flow in the large aspect ratio channels of such dies is modelled using a Hele-Shaw formulation. The pressure field in the die causes a change of the flow channel dimensions, and hence alters the melt distribution. An experimental technique is applied to determine this die body deflection in a 1.3m commercial die; it is found to be substantial. Modelling of the die deformation using a commercial 3-D finite element package is described, with the load being based on a pressure field previously determined in the undeflected flow channel geometry. Prompted by unsatisfactory results, an algorithm is developed to evaluate the die body deflection iteratively, by coupling a 2-D thick plate analysis with the Hele-Shaw flow analysis, resulting in significantly improved results. Modelling of the conjugate melt flow/die heat transfer problem on the die cross-section is also carried out. Viscous heat generation, conduction and convection energy transport in the melt coupled with heat conduction in the die body are considered, together with the influence of electrical die heating and heat losses from the die surfaces by convection and radiation. Conclusions are drawn on thermal aspects of die design and operation. A graphical user interface embedded in Microsoft Windows is developed for a number of finite element codes, facilitating their use by non-specialists, and providing graphical displays of results. An outline of the operation of the complete package is described, including a convenient contouring algorithm.
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Kienhöfer, Frank Werner. "Heavy vehicle wheel slip control." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609594.
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Matička, Jiří. "Extrakce klíčových slov z dokumentů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236533.
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This thesis pursues an automated extraction of keywords from documents. Its goal is to design and implement an application which will be able to extract an appropriate set of keywords related to the contents of the document. The major requirements for the application are speed and accuracy. That is why the first part of the thesis talks about already developed principles and a detailed classification based on various criteria. The second part is focused on choosing and a thorough functional describing of one of the methods which should have been used for extracting the keywords. The next parts contain a detailed draft of the application and its implementation. Finally, the last chapter is particularly important due to testing the application on a group of text documents and evaluating final results of the extraction process.
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Adamson, Alan, and Albert Berdugo. "Helicopter Slip Ring Replacement System." International Foundation for Telemetering, 2010. http://hdl.handle.net/10150/604271.
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ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, CaliforniaMost helicopter programs require the acquisition of parameters from the rotating systems. Historically, these systems made use of electromechanical slip rings for the transfer of power, control, and data from within the helicopter's cabin to the rotating hardware. Slip rings are primarily used in dedicated instrumentation vehicles and are not commonly used in production platforms that may require instrumentation of the rotating systems for in-service load and fatigue monitoring. Additionally, the use of slip rings requires time and money to integrate the hardware and equipment into the aircraft in order to perform rotor data acquisition. The time needed to perform modifications to transmissions and drive trains plays a big factor in the increased costs of aircraft development. Less intrusive installations would minimize the need for mechanical changes and would improve the time needed to install the instrumentation. This paper describes a wireless system approach to perform the test without the slip ring, and provides performance data that validates this new method of instrumenting unobtrusively to save time and money without sacrificing data integrity.
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Sperry, Ryan Aaron. "Characterization of Slip Activity in the Presence of Slip Bands Using Surface-Based Microscopy Techniques." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8680.
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Further understanding of mesoscale slip mechanics is crucial to future development of polycrystalline metals with improved performance. The research contained within this thesis aims to characterize localized mesoscale slip on slip bands further through two studies. First, a comprehensive comparison of slip system identification techniques was carried out to further validate each method as well as compare advantages and disadvantages of each. Second, slip bands in the presence of grain boundaries were studied to better characterize the dislocation content and behavior. In the first study, the use of SEM-DIC, AFM, ECCI, and HR-EBSD to characterize slip-system activity was assessed on the same material volume of Ti-7Al. This study presents a robust comparison of the various methods for the first time, including an assessment of their advantages and disadvantages, and how they can be used effectively in a complementary manner. The analysis of the different approaches was carried out in a blind manner independently at three different universities. A Ti-7Al specimen was deformed in uniaxial tension to approximately 3% axial strain, and the active slip systems were independently identified using (i) trace analysis; (ii) in-SEM digital image correlation, (iii) observations of residual dislocations from ECCI, and (iv) long-range rotation gradients through HR-EBSD, with consistent trace identification in all cases. Displacement data from AFM was used to augment the SEM-DIC displacement data by providing complementary out of plane displacement information. Furthermore, short-range dislocation gradients (measured by DIC) provided insight into the residual geometrically necessary dislocation (GND) content, and was consistent with the GND content extracted from EBSD data and ECCI images, confirming the presence of residual GNDs on the dominant slip systems resulting in visible slip bands. These approaches can be used in tandem to provide multi-modal information on slip band identification, strain and orientation gradients, out-of-plane displacements, and the presence of GNDs and SSDs, all of which can be used to inform and validate the development of dislocation-based crystal plasticity and strain gradient models. In the second study, shear strain profiles along slip bands in a modified Rolls-Royce nickel superalloy (RR1000) were analyzed for a tensile sample deformed by 2%. The strain increased with distance away from a grain boundary (GB), with maximum shear strain towards the center of the grain, indicating that dislocation nucleation generally occurred in the grain interior. The strain gradients in the neighborhood of the GBs were quantified and generally correlated with rotation about the active slip system line direction. This leads to an ability to determine the active slip system in these regions. The dislocation spacing and pileup stresses were inferred. The dislocation spacing closely follows an Eshelby analytical solution for a single ended pileup of dislocations under an applied stress. The distribution of pileup stress values for GBs of a given misorientation angle follows a log-normal distribution, with no correlation between the pileup stress and the GB misorientation angle. Furthermore, there is no observed correlation between various transmissivity factors and slip band pileup stress. Hence it appears that the obstacle strength of any of the observed GBs is adequate to facilitate the dislocation pileups present in the slip bands. However, slip band transmission does correlate with transmissivity factors, with the current study focusing on the Luster and Morris m'-factor. Observation of strain profiles of transmitted bands indicate dislocation nucleation locations.
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Grandin, Sara, and Anna Pettersson. "Fastighetsmäklare - mycket slit och dåliga villkor?" Thesis, University of Gävle, Department of Business Administration and Economics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-584.
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Fastighetsmäklare har ett rykte att de tjänar mycket pengar utan att anstränga sig. Stämmer detta eller är det bara en bild som media skapat? Med den bakgrunden valde vi att titta närmare på vilka lönesystem för fastighetsmäklare som finns i branschen. Med avgränsning till privatbostadsmarknaden och Stockholm-Uppsala regionen.
Syftet är att öka kunskapen om olika lönesystem för fastighetsmäklare på privatbostadsmarknaden.
Vi har även tittat på hur det fungerar med sjukpenning, föräldrapenning och a-kassa. Sedan har vi valt att titta på hur en mer traditionell lön ser ut och vilka förmåner utöver lön som kan förekomma.
Vi har genomfört två intervjuer angående hur en traditionell eller ”normal” lön fungerar samt fyra intervjuer med fastighetsmäklare angående lönesystem för fastighetsmäklare.
Real estate agents have a reputation of making a lot of money without any effort. Is this true or is it just a picture painted by the media? With this in mind we have decided to take a closer look at different systems for how real estate agents get their salary. We have decided to narrow our thesis down to real estate agents who are operating in the Uppsala-Stockholm region with residential sales.
The purpose of this thesis is to increase the knowledge about different systems for salaries for real estate agents who are working with residential sales.
What happens if you get sick, if you become a parent or if you loose your employment are questions that we discuss.
We have interviewed real estate agents and asked them about their terms for salary. We have also looked at how a more traditional salary works.
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Frylmark, Daniel, and Stefan Johnsson. "Automatic Slip Control for Railway Vehicles." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1765.
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In the railway industry, slip control has always been essential due to the low friction between the wheels and the rail. In this master’s thesis we have gathered several slip control methods and evaluated them. These evaluations were performed in Matlab-Simulink on a slip process model of a railway vehicle. The objective with these evaluations were to show advantages and disadvantages with the different slip control methods.
The results clearly show the advantage of using a slip optimizing control method, i.e. a method that finds the optimal slip and thereby maximizes the use of adhesion. We have developed two control strategies that we have found superior in this matter. These methods have a lot in common. For instance they both use an adhesion observer and non-linear gain, which enables fast optimization. The difference lies in how this non-linear gain is formed. One strategy uses an adaptive algorithm to estimate it and the other uses fuzzy logic.
A problem to overcome in order to have well functioning slip controllers is the formation of vehicle velocity. This is a consequence of the fact that most slip controllers use the velocity as a control signal.
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Williams, Cheri Lynne. "Egyptian Red Slip Pottery at Aila." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-08172009-104842/.
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The Roman Aqaba Project, an archaeological investigation of a Roman port on the Red Sea in southern Jordan, recovered over 500 sherds of Egyptian Red Slip Ware (ERS). This included both ERS A (presumably from the Aswan region of Upper Egypt) and ERS B (from various production centers along the Nile valley). ERS was the second most common imported fine ware found at Aila from the Late Roman and Byzantine periods (3rd through early 7th centuries A.D.), trailing far behind African Red Slip Ware (from Tunisia) but easily exceeding imports of Cypriote Red Slip and Phocaean Red Slip (from the Aegean). The most striking fact about the ERS at Aila is its chronological distribution. In most parts of Palestine and Jordan ERS appears in quantity only in the late 6th and 7th centuries. But at Aila both ERS A and ERS B wares begin appearing in securely attested 3rd century contexts and are most common in the 4th century, long before their appearance in the remainder of the Levant, generally in late 6th and 7th centuries.
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Ranvik, Arne. "Slip Prediction Based on Manipulator Motion." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-26705.
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Predicting slip during robotic manipulation is of interest for a variety of appli-cations. Especially applications where weak grasps are applied. In this thesis, amodel for predicting slip for a two fingered grasping scenario is considered. Otherthan model parameters, the only measurements or sensor information assumed isof the manipulator joints. Soft objects that deform substantially under appliedforces are especially interesting in terms of frictional behaviour. A soft ball wasused as a test object and parameters for friction and deformation was experimen-tally determined. By grasping and moving the ball with an industrial manipulator,slip and object loss was induced in order to compare these observations againstmodel predictions.It was found that the models prediction of slip was reasonable when compared tothe observations. However, the model could not be fully tested and validated be-cause the simple geometry of the test object did not excite any frictional behaviourfrom the soft characteristics.
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Nibur, Kevin Andrew. "Nanoindentation slip steps and hydrogen embritlement." Online access for everyone, 2005. http://www.dissertations.wsu.edu/Dissertations/Summer2005/k%5Fnibur%5F071305.pdf.
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Klusák, Martin. "Zvuk v celovečerním filmu beze slov." Master's thesis, Akademie múzických umění v Praze.Filmová a televizní fakulta. Knihovna, 2013. http://www.nusl.cz/ntk/nusl-172875.
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The main goal of this thesis is to describe the unofficial genre of films without speech and to analyze principles of the use of sound and film language in such films.
Initial chapters speak generally about the phenomenon of feature nonverbal cinema with the focus on its historical development and general film language.
The middle part presents, and briefly describes chosen films without speech, and suggests their sorting into sub-genres.
The last, vastest part of the work, is an analytic study of various approaches to reduce speech generally throughout film. This part leads into the final theoretical description of soundtrack in films without speech.
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Krotký, Jan. "Dekodér pro systém detekce klíčových slov." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218176.
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The essay presents the basic characteristics of human speech recognition, describes systems for the detection of key words and further deals with the proposal of each decoder blocks divided into three chapters. The first one describes the operations that are performed before the signal distribution of the framework and the segmentation. The second chapter describes the calculation of short-term energy, the number of zero passes and self-correlative, prediction and Mel-frequency cepstral coefficients. The third chapter, which describes the design of the block decoder, describes the method of dynamic time destruction and the method based on hidden Markov model. The final part of the essay describes decoders working with a speech and a proposal for a simple decoder working with isolated words, which was based issued and tested based on the preceding chapters.
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Zemánek, Tomáš. "Detekce klíčových slov v mluvené řeči." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229642.
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This thesis is aimed on design keyword detector. The work contains a description of the methods that are used for these purposes and design of algorithm for keyword detection. The proposed detector is based on the method of DTW (Dynamic Time Warping). Analysis of the problem was performed on the module programmed in ANSI C, which was created within the thesis. The results of the detector were evaluated using the metrics WER (word error rate) and AUC (area under curve).
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Pfeifer, Václav. "Detekce klíčových slov v řečových signálech." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-233599.
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Speech processing systems have been developed for many years but the integration into devices had started with the deployment of the modern powerful computational systems. This dissertation thesis deals with development of the keyword detection system in speech data. The proposed detection system is based on the Large Margin and Kernel methods and the key part of the system is phoneme classifier. Two hierarchical frame-based classifiers have been proposed -- linear and non-linear. An efficient training algorithm for each of the proposed classifier have been introduced. Simultaneously, classifier based on the Gaussian Mixture Models with the implementation of the hierarchical structure have been proposed. An important part of the detection system is feature extraction and therefor all algorithms were evaluated on the current most common feature techniques. A part of the thesis technical solution was implementation of the keyword detection system in MATLAB and design of the hierarchical phoneme structure for Czech language. All of the proposed algorithms were evaluated for Czech and English language over the DBRS and TIMIT speech corpus.
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Kyjovský, Marek. "Extrakce klíčových slov z vědeckých článků." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2010. http://www.nusl.cz/ntk/nusl-237148.
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The main goal of this thesis is to explore basic methods which is using for extraction of important words from articles. After that try to understand character of using keywords from the available set of testing English articles. Based on these findings, try to design and to implement a system which is using this methods. Then created system testing on the real English articles and after that try to analyse results.
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Havelková, Simona. "Vliv slev na nákupní chování zákazníků." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-197440.
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The master's thesis deals with promotional discounts of retail chains focusing on a description of factors that affect customers in selection of a shopping place to purchase food and beverages and identifies the level of influence of promotional discounts on purchase decisions. This thesis is divided into two parts. The theoretical part contains fundamental resources, that are enriched by findings of foreign case studies. It focuses on consumers behavior and purchase decisions emphasizing the influence of prices and special offers. The practical part consists of secondary research of current trends in shopping behavior of Czech consumers, primary analysis of the action flyers and research focused on describing the attitudes of consumers towards the retail chains and identifying the impact of promotional discounts on purchasing food products. The recommendations for marketing activities of retail chains are formulated based on the results of the analysis.
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Battye, Robin Antony. "Repulsive signaling from the Drosophila midline requires slit function : repellent signaling through robo1 requires the slit LRR /." *McMaster only, 2000.
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Schmalzle, Gina Marie. "The Earthquake Cycle of Strike-Slip Faults." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/177.
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An earthquake is a mechanism of stress release along plate boundaries due to relative motion between the Earth's lithospheric blocks. The period in which stresses are accruing across the plate boundary is known as the interseismic portion of the earthquake cycle. This dissertation focuses on interseismic portion of the earthquake cycle to extract characteristics of fault, shear zone and rock properties. Global Positioning System (GPS) data are used to observe the pattern of deformation across two primarily strike-slip fault systems: the Carrizo Segment of the San Andreas Fault (SAF) and the Eastern California Shear Zone (ECSZ). Two sets of GPS data are processed, analyzed and applied to analytic and numerical models describing the interseismic behavior of the earthquake cycle. The Carrizo segment is mature (i.e., had many earthquakes) and has juxtaposed terrains with varying rock properties laterally across the fault system. Lateral variations in rock properties affect the pattern of deformation around strike-slip faults and affect how surrounding rock deforms and if not considered may bias the interpretation of the faulted system. The Carrizo segment separates Franciscan terrain northeast of the fault from Salinian block to the southwest. GPS data are well fit to a model with a 15-25 km weak zone northeast of the Carrizo segment. The long-term slip rate estimated on the SAF is 34-38 mm/yr, with 2-4 mm/yr accommodated on faults to the west. The viscosity for the combined lower crust/upper mantle is estimated at 2-5x10^19 Pa s. This model is consistent with the distribution of rock type and corresponding laboratory data on their material properties, paleoseismic, seismic and magnetotelluric data. The ECSZ is a young (<10 >Myr) system of strike-slip faults including the Owens Valley - Airport Lake, Panamint Valley - Ash Hill - Hunter Mountain and Death Valley - Furnace Creek fault systems. The ECSZ study concentrates on fault evolution by finding the current position of maximum shear across the shear zone and estimating fault rates. Geologic studies suggest that the Death Valley - Furnace Creek fault system on eastern end of the ECSZ was the primary accommodator of slip early in the ECSZ history. This study suggests that the current locus of shear has shifted westward, and resides in the center of the ECSZ under the Panamint Valley - Ash Hill -Hunter Mountain fault system. The model dependent estimated geodetic rate of the Ash Hill - Panamint Valley -Hunter Mountain fault system (4.91-6.11 mm/yr) is faster than geologic estimates (1.6 - 4 mm/yr). The result is interpreted as a simplification of the ECSZ with time, combined with progressive westward migration of deformation. The best estimate for a combined rate across the shear zone is 10 mm/yr (20% of total Pacific-North America motion). The summation of rates obtained by this study is 49 mm/yr, well within estimates obtained by previous studies using independent techniques.
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Lloyd, Jeffrey Townsend. "Implications of limited slip in crystal plasticity." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34808.
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To better understand consequences of classical assumptions regarding deformation mechanisms at the mesoscale, experimental observations of mesoscale deformation are presented. In light of actual micrographics of deformed polycrystals, the Von Mises criterion which states that 5 independent plastic deformation sources are needed at each material point to satisfy compatibility is studied, and the consequences of violating this assumption are presented through comprehensive parametric studies. From these studies, it can be concluded that not only are 5 independent plastic deformation sources not needed or observed at each point, but if less than 5 sources are allowed to be active a new physical understanding of a mechanism for kinematic hardening emerges. Furthermore, for enhanced subgrain rotation and evolution the Von Mises criterion must be violated. The second focus of this work is looking at studies, experiments, and models of mesoscale deformation in order to better understand controlling deformation length scales, so that they can be fed into a combined top-down, bottom-up, non-uniform crystal plasticity model that captures the variability provided by the mesoscale during deformation. This can in turn be used to more accurately model the heterogeneity provided by the response of each grain. The length scale intuited from insight into mesoscale deformation mechanisms through observation of experiments and analytical models is the free slip line length of each slip system, which informs non-uniform material parameters in a crystal plasticity model that control the yielding, hardening, and subsequent softening of each individual slip system. The usefulness of this non-uniform multiscale crystal plasticity model is then explored with respect to its ability to reproduce experimentally measured responses at different strain levels for different size grains. Furthermore, a "Mantle-Core" type model which combines both the non-uniform material parameter model and the limited slip model is created, in which the majority of plastic deformation is accommodated near the grain boundary under multi-slip, and uniform plastic deformation occurs in the bulk dominated by double or triple slip. These models are compared for similar levels of hardening, and the pole figures that result from their deformation are compared to experimental pole figures. While there are other models that can capture the heterogeneity introduced by mesoscale deformation at the grain scale, this combined top-down, bottom-up multiscale crystal plasticity model is by far one of the most computationally efficient as the heterogeneity of the mesoscale is does not emerge by introducing higher order terms, but rather by incorporating the heterogeneity into a simple crystal plasticity formulation. Therefore, as computational power increases, this approach will be among the first that will be able to perform accurate polycrystal level modeling while retaining the heterogeneity introduced by non-local mesoscale deformation mechanisms at the sub-grain scale.
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Yin, Lan 1969. "GPS based positioning with cycle slip detection." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79206.
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This thesis is concerned with development and implementation of an efficient and numerically reliable positioning algorithm based on the combination of code pseudorange (C/A) and carrier phase (L1) measurements with cycle slip detection.In GPS a typical technique for kinematic position estimation is relative positioning where two receivers are used, one receiver is stationary and its exact position is known, the other is roving and its position is to be estimated. We describe the physical situation and give the mathematical model based on the difference of the measurements at the stationary and roving receivers. The model we consider combines both code pseudorange and carrier phase measurements. We then present: a recursive least squares approach for position estimation. We take full account of the structure of the problem to make our algorithm efficient, and use orthogonal transformations to ensure numerical reliability of the algorithm.
At each epoch, possible cycle slips must be detected, otherwise it may significant deteriorate the positioning accuracy. A cycle slip detection method based on the higher-order difference technique, one of typical techniques for cycle slip detection, is developed and incorporated into the preprocess of our positioning algorithm.
Finally, real data testing for our positioning algorithm and cycle slip detection algorithm are performed. The results suggest our algorithms are very effective.
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Smillo, Fabricio. "Wall slip and spurt of molten polymer." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81570.
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A Monsanto Automatic Capillary Rheometer and a sliding plate rheometer were used to study the spurt phenomenon and to discover whether it is the result of a system instability or a material property. The capillary rheometer has been the only instrument able to operate at spurt stresses up to present time, because capillary rheometers operate at shear stresses that are out of the range of rotational shear rheometers. However, a sliding plate rheometer can generate shear stresses in the spurt range. A comparative study using two linear polybutadiene samples at 50°C was carried out using these two rheometers. Special attention was paid to the evaluation of the actual pressure drop in the capillary in order to determine the true shear stress at the wall. It was found that spurt occurs only in the capillary rheometer. In other words, the flow curve generated by the sliding plate rheometer is continuous in the shear stress range where spurt is observed in the capillary rheometer. Slip velocities were determined using data from the two rheometers, and the slip velocities for the post-slip capillary flow all fall on the smooth curve based on sliding plate data, provided that the pressure drop in the capillary, and not the overall driving pressure, is used to calculate the wall shear stress.
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Breguet, Jean-Marc Breguet Jean-Marc. "Actionneurs "stick and slip" pour micro-manipulateurs /." [S.l.] : [s.n.], 1998. http://library.epfl.ch/theses/?display=detail&nr=1756.
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Lai, Derek. "Crack shear-slip in reinforced concrete elements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ62951.pdf.
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Smith, Jonathan Hurndall. "Stick-slip vibration and is constitutive laws." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304168.
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Qiu, Hui. "Slip and edge effect in complete contacts." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:d4ea2006-5a87-46c6-be0d-2a4c55b272da.
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The general problem of an anticrack, present in a simple domain and subject to general remote loading is solved using distributed line forces, acting as strain nuclei, along the line of the anticrack. Subsequently, both dislocations and point forces are used as strain nuclei to achieve mixed boundary value conditions. The influence function for a pair of forces applied to the faces of a semi-infinite notch is found and finally this is used to find the true closure length and interfacial contact pressure. When a sharp-edged indenter is pressed into a half plane material in the half-plane is displaced and 'laps around' the edges of the punch, possibly making contact with the side faces. This phenomenon is quantified within (coupled) half-plane theory, and applied first to an idealised indenter having the cross section of a trapezium, and then to a semi-infinite indenter. The latter allows an asymptotic form to be found which, through a generalised stress intensity factor may be collocated into the edge of any notionally sharp-edged indentation problem. The effect of surface strains on the local slip angle, when an infinite cylinder is slid skew-wise across an elastically similar half-plane is found. It is shown that local frictional orthogonality is not completely consistent with global orthogonality. The problems of a square-ended and an almost square-ended rigid punch sliding with both plane and anti-plane velocity components are studied. It is shown that, for a truly complete contact, if the contacting body is incompressible, convection effects are absent. Introducing either: (a) local rounding or (b) finite compressibility of the contacting body into the problem introduces convection, giving rise to an inconsistency between the global and local requirement of the orthogonal friction law. The state of stress in a three-quarter-plane undergoing antiplane shear deformation is studied, due to the presence of a screw dislocation along one of the projection lines extending from the free surfaces. A simple, accurate formula for the state of stress along the line is found, providing a useful kernel for the solution of crack and contact edge slip problems. The state of stress induced in an axi-symmetric solid formed from a half-space and a bonded semi-infinite rod, by a family of ring dislocations of arbitrary Burgers vector is found. Particular care is given to the interaction between the Cauchy singularity near the dislocation core and the geometric singularity at the rod/half-space junction. Torsional contact between a semi-infinite elastic rod with square ends and an elastically similar half-space was then solved using the ring dislocations as influence functions. This provides an excellent illustration of the imposition of orthogonality condition for a complete contact.
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Sainoki, Atsushi. "Dynamic modelling of mining-induced fault-slip." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123291.
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In deep hard rock mines where high stress conditions take place, rockbursts are serious problems because rockbursts could result in severe damage to mine openings. It is widely recognized that mining activities could reactivate faults in underground mines. The reactivation of faults could then cause fault-slip. More importantly, fault-slip gives rise to seismic waves, which inflict severe damage to mine openings. Because the generation and propagation of seismic waves are dynamic phenomena, fault-slip needs to be also dealt with as a dynamic phenomenon. Both of the static and dynamic behaviour of faults should be examined, considering the effects of mining activities on the faults, in order to estimate the damage induced by the seismic waves First, a literature review is conducted. The review has revealed that although a number of dynamic and static friction laws have been proposed, the friction laws have been rarely employed for the simulation of fault-slip in underground mines. The review has also revealed that most of the simulations have been conducted in static conditions. In this thesis, dynamic modelling of mining-induced fault-slip is presented using a mine-wide model encompassing a fault. Furthermore, a case study of Garson Mine, Sudbury, Canada is carried out. A parametrical study with a mine-wide 3D model has led to the following conclusions: (a) mining depth, friction angle of the fault, and fault locations exert a large influence on the maximum relative shear displacements on the fault, while the dilation angle and stiffness of the fault do not, (b) maximum slip rates appear to increase with the maximum slip. Results obtained from the numerical analysis employing Barton's shear strength model have shown that fault surface roughness strongly affects the intensity of seismic waves and seismically radiated energy. The results imply that fault-slip occurring on faults with rough surfaces could become more violent. The effect of stope production blasts on a nearby fault is also examined. The results obtained from the analysis have indicated that performing stope production blasts in timed sequence could induce a larger seismic event on the fault than triggering the blasts simultaneously. Dynamic analysis considering the collision and unloading of fault surface asperities is also conducted. It is found that the release of normal stress due to fault unloading has a large influence on the intensity of seismic waves. The effect of slip-weakening distance on seismic source parameters of fault-slip is also investigated. The study has indicated that slip rates and seismically radiated energy are significantly affected by the slip-weakening distance, while seismic moment appears not to be susceptible to the slip-weakening distance in a case of local fault-slip.Back analysis of fault-slip to estimate the physical and mechanical properties of shear/fracture zones is carried out for Garson Mine. The back analysis is conducted with respect to moment magnitude and peak particle velocities recorded by seismic monitoring systems. Fault surface roughness and a dynamic friction angle have been calibrated. Afterwards, the calibrated values are validated with peak ground acceleration. Through the study, a methodology to calibrate the physical and mechanical properties of faults by means of ground motion due to seismic waves arising from fault-slip as well as seismic source parameters of the fault-slip has been developed.Dans les mines profondes ou des contraintes élevées se produisent, les coups de terrain sont un problème car les ils peuvent endommager les ouvertures minières. Il est largement reconnu que les activités minières peuvent réactiver des failles dans les mines sous-terraines. La réactivation de ces failles peut entrainer un glissement de faille. Surtout, le glissement de faille fait naitre des ondes sismiques qui infligent des dégâts sérieux quand elles frappent la surface des ouvertures minières. La génération et la propagation des ondes sismiques sont des phénomènes dynamiques. Il s'ensuit donc que le glissement de faille doit être traité comme un phénomène dynamique Le comportement dynamique ainsi que le comportement statique des failles doit être examiné en considérant les effets des activités minières pour estimer les dégâts causés par les ondes sismiques.Premièrement, un examen de la documentation est effectué. L'examen a révélé que même si un nombre de lois statiques et dynamiques de frottement ont été proposés, ces lois de frottement ont été peu employés pour simuler les glissements de faille que se déroulent dans les mines sous-terraines. La revue a aussi révélé que la majorité des simulations ont été conduites en conditions statiques. Dans cette thèse, la modélisation dynamique d'un glissement de faille induit par des activités minières est présentée. Le modèle englobe l'entièreté d'une mine. En plus, une étude de cas pour la mine Garson à Sudbury, au Canada, est effectuée.Une étude paramétrique avec un modèle de mine en trois dimensions mène aux conclusions suivantes: (a) la profondeur d'exploitation minière, l'angle de friction de la faille, et la position de la faille ont une grande influence sur les déplacement relatifs en cisaillement d'une faille, tandis que l'angle de dilation de la faille et la dureté ont peu d'effet, (b) le taux de glissement maximal augmente en fonction du glissement absolu. Les résultats obtenus du modèle numérique dans lequel le modèle de résistance au cisaillement de Barton est implémenté ont démontré que la rugosité de la surface de la faille affecte grandement l'intensité des ondes sismiques qui émanent du glissement de faille et l'énergie sismique propagée. Les résultats impliquent qu'un glissement de faille survenant à une faille rugueuse est plus violent. L'effet produit par un sautage de production sur une faille proche est aussi examiné en considérant plusieurs séquences de sautage. Les résultats de l'analyse indiquent qu'un sautage de production exécuté selon une séquence temporelle peut induire un plus grand événement sismique qu'un sautage simultané. Une analyse dynamique tenant compte la collision et le déchargement d'une faille est aussi conduite. Il est démontré que le relâchement de la contrainte normale à la faille a une grande influence sur l'intensité des ondes sismiques. L'effet de la distance d'affaiblissement de faille due glissement sur les paramètres sismiques est aussi examiné L'étude indique que le taux de glissement et l'énergie sismique émanée sont significativement affectés par la distance d'affaiblissement de faille, tandis que le moment sismique n'est pas susceptible à la distance d'affaiblissement dans le cas ou le glissement de faille se déroule seulement dans une zone limitée. Pour estimer l'effet des propriétés physiques et mécaniques de la zone de cisaillement, une analyse régressive est exécutée pour la mine Garson. L'analyse est conduite selon la magnitude du moment et la vitesse de crête des particules. La rugosité de la surface de la faille et l'angle de friction dynamique sont étalonnés. Ensuite, les paramètres étalonnés sont validés par rapport à l'accélération maximale du terrain. À travers l'étude, une méthodologie pour étalonner les propriétés physiques et mécaniques de la faille selon l'étude du mouvement du terrain due aux ondes sismiques émanant d'un glissement de faille est développé.
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Shaw, Graham David. "New techniques in astronomical multi-slit spectroscopy." Thesis, Durham University, 1993. http://etheses.dur.ac.uk/5643/.
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LDSS-2 is a low dispersion survey spectrograph for the William Herschel Telescope. It was constructed to meet an increasing demand for large scale statistical surveys of stellar and galactic populations. This thesis describes its design, construction and installation, together with additional research concerning the fabrication of multi-slit aperture masks.LDSS-2 has a similar optical system to its predecessor LDSS-1, but it can hold greater numbers of aperture masks, filters and grisms, and its control system is fully automated. This is expected to improve its observing efficiency and allow LDSS-2 to be run as a common-user instrument. A range of instrument characterisation tests were performed, and they confirmed that LDSS-2 is capable of meeting its astronomical objectives. Its peak efficiency with the medium-blue grism was found to be 20.4% at 5915A with half-power points at 4135A and 7225A.Six different types of aperture mask were investigated, of which two (photochemically etched and mechanically milled) were tested using LDSS- 2. Work was begun towards the development of laser-cut masks, including the procurement of a 16W carbon dioxide laser and a motorised X-Y table. At present, mechanically milled masks offer the best compromise between cost, lead time, flexibility and quality for an instrument such as LDSS-2. Movable-slit masks may be preferred if access to the focal plane is restricted, but at present they are limited to lower multiplex gains. Laser-cut masks appear to offer the most potential for development in the immediate future, but liquid crystal masks may also become competitive in the longer term.
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Webber, Mark. "Instability of fluid flows, including boundary slip." Thesis, Durham University, 2007. http://etheses.dur.ac.uk/2308/.
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We investigate the onset of instability in a variety of fluid models, and present results and details of their computation in each case. The fluid models we consider are: convection in the setting of the Navier-Stokes equations with boundary slip; Poiseuille-type solutions of the Navier-Stokes equations, again with boundary slip; Poiseuillfe-type solutions of the Green-Naghdi and dipolar fluid equations. In Chapter two we examine the onset of thermal convection in a thin fluid layer, with slip boundary conditions at the top and bottom surfaces of the layer. We show that non-zero boundary conditions do not affect the classical steady state solution, and the principle of exchange of stabilities still applies. It is seen that boundary slip reduces the critical Rayleigh number at which convection begins, below that found in the setting of no-slip boundary conditions. The next two chapters concern the transition to turbulence of pressure driven flow in a microchannel, at the boundaries of which the fluid obeys slip boundary conditions. In Chapter three we perform linear and nonlinear stability analyses for this flow, and show that we do not have exchange of stabilities for such flows. In Chapter four we perform a linear stability analysis for channel flow in the case when the fluid viscosity is a function of temperature. We show that for pressure driven flow in the plane, boundary slip stabilizes the flow. In Chapter five we develop a model of thread-annular flow, in which we believe boundary slip to be an important part. As well as our development of the model, we present previously unpublished results on the linear stability of thread-annular flow to non-axisymmetric disturbances. Some surprising behaviour is observed in the neutral curves, including behaviour missed by the computations of previous authors. Finally, we use Chapter six to discuss two alternative fluid models: the Green- Naghdi equations and the dipolar equations. We find Poiseuille flow type solutions in both of these settings, and perform linear stability analyses. These fluid models are systems of fourth order differential equations, and we show that the fourth order derivative terms dominate the stability of the flow.