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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Machine Learning Applications for Downscaling Groundwater Storage Changes Integrating Satellite Gravimetry and Other Observations

Agarwal, Vibhor January 2021 (has links)
No description available.
332

Fenomén prázdné galerie / The phenomenon of empty gallery

Brožka, Petr January 2015 (has links)
The doctoral thesis deals with the topic of exihibiting of an empty gallery. The problem of the emptiness is presented by using a prism of theory of art, semiotics and phenomenology, more precisely hermeneutics. The matter is in a relation with some remote domains, it tries to give a definition of substance and general rules by exihibiting of the emptiness in a gallery. According to one of the presented propositions the plain emptiness itself comes to be an artwork. By semantics of logic method the text is tryiing to form another proposition about specific emptiness in a gallery that generates artwork naturally. The text tries to reopen the theme of some crucial problems in conceptual art. It presents an explanation of the aplication of conceptual method to general public.
333

Entwicklung wartungsfreier und rein elastisch beanspruchter Gleitlager auf Basis keramischer Werkstoffe

Stentzel, Christian 19 June 2019 (has links)
Die vorliegende Arbeit beschreibt den Einsatz von Hochleistungskeramiken im Bereich der Gleitlagertechnik. Dabei liegt der Fokus auf das keramikgerechte Design, welches die umge-bende Struktur mit einbezieht. Insbesondere die Einbettung aber auch der Bolzen sind durch konstruktive Maßnahmen zu adaptieren, sodass eine möglichst geringe Zugspannung unter Last im keramischen Werkstoff entsteht. Parameterstudien mit Hilfe der FEM erlauben die Aufstellung von Anforderungen an das Design nach dem Kriterium des Spannungsminiums und in Abhängigkeit der Lagergröße und -belastung sowie des verwendeten keramischen Werkstoffes. Eine experimentelle Validierung des keramikgerechten Designs bestätigt eine statische und dynamischer Tragfähigkeit bis mindestens 150 N/mm². Weiterhin wird ein Weg eines fluidfreien und wartungsfreien Tribologiesystems für keramische Werkstoffe aufgezeigt, das einen geringen Reibwert von kleiner 0,1 und einen nicht messbaren Verschleiß aufweist. Optimierungspotenzial besteht hinsichtlich des erreichbaren Gleitweges. Abschließend wird eine Berechnungsvorschrift zur Dimensionierung eines keramischen Gleitlagers gegeben.:Abbildungsverzeichnis VIII Tabellenverzeichnis XI Symbole und Abkürzungen XII 1 Einleitung und Zielsetzung 1 2 Stand der Technik und Wissenschaft 3 2.1 Technische Merkmale und Marktanalyse heutiger Gleitlager 3 2.2 Keramische Werkstoffe 7 2.3 Hochleistungskeramik in hochbeanspruchten Gleitanwendungen sowie Präzisierung der Aufgabenstellung und angewandten Methoden 14 3 Berechnungsmethoden für keramische Werkstoffe 18 3.1 Spannungszustand im keramischen Bauteil 18 3.2 Zulässige Spannung und Sicherheitsbeiwert für keramische Werkstoffe 20 3.3 Lebensdauerbestimmung mittels Messmethoden 24 4 Mechanisches Design eines keramischen Gleitlagers (mechanische Lebensdauer) 26 4.1 Verbindungselement Koppelstange und typische Lastsituationen 26 4.2 Konstruktive Voraussetzungen für eine rein elastische Beanspruchung 27 4.3 Parameterstudien zu konstruktiven Einflussgrößen und deren Auswirkung auf die mechanische Beanspruchung 30 4.3.1 Einfluss der Fertigungsqualitäten des Lagersitzes 31 4.3.2 Einfluss der Gleitlagerbuchsen- und Einbettungssteifigkeit 32 4.3.3 Einfluss der Bolzenballigkeit 36 4.3.4 Einfluss der Einbettungsbauform 36 4.3.5 Einfluss der Lagerbelastung und des Nenndurchmessers 40 4.3.6 Einfluss der Lagerluft 41 4.3.7 Weitere Parameterstudien 42 4.4 Ableitung von Konstruktions- und Werkstoffanforderungen 43 4.5 Experimentelle Festigkeitsuntersuchung 45 4.5.1 Prüfstandsvorrichtungen 46 4.5.2 Proben zur Festigkeitsuntersuchung und Messprogramm 47 4.5.3 Statische und dynamische Tragfähigkeit keramischer Gleitlager 49 5 Design eines fluidfreien und reibwertreduzierten Tribologiesystems (tribologische Lebensdauer) 51 5.1 Allgemeine und keramische Tribologie 53 5.2 Zusammenfassung tribologischer Kennwerte einer Si3N4-Stahl-Paarung 57 5.3 Möglichkeiten zur Reibwert- und Verschleißreduzierung 59 5.4 Experimentelle Analyse des Tribologiesystems 65 5.4.1 Tribologiesystem und Abbruchkriterien 65 5.4.2 Tribologische Proben und Messprogramm 69 5.4.3 Ergebnisse zum Reibwert und zum erzielbaren Gleitweg 74 5.4.4 Verschleißzustände und tribologisches Verhalten 78 5.4.5 Diskussion der tribologischen Ergebnisse 83 6 Berechnungsvorschrift zu rein elastisch beanspruchten Gleitlagerbuchsen nach dem Spannungsminimum 85 7 Zusammenfassung und Diskussion der Ergebnisse 90 8 Ausblick 93 Literaturverzeichnis 95 Anlagenverzeichnis 97 / This paper describes an application of ceramics in the plain bearing technology. The main issue is the specific ceramic design including the surrounding structure. Especially the embedding as well as the bold have to be adapted to minimize the tensile stress of the ceramic in operation. Parametric studies based on FEM allowing to define the design requirements depending on the criteria of minimum stress, size of bearing, bearing load and ceramic material. Experiments verify the ceramic design regarding to a static and dynamic load rating of 150 N/mm². Furthermore an opportunity is shown to create a fluid free and maintenance-free tribology system for ceramics which has a coefficient of friction less than 0,1 and a not measurable wear. The sliding distance limit has to be optimize. In summary it is given a calculation regula-tion to dimension a ceramic plain bearing.:Abbildungsverzeichnis VIII Tabellenverzeichnis XI Symbole und Abkürzungen XII 1 Einleitung und Zielsetzung 1 2 Stand der Technik und Wissenschaft 3 2.1 Technische Merkmale und Marktanalyse heutiger Gleitlager 3 2.2 Keramische Werkstoffe 7 2.3 Hochleistungskeramik in hochbeanspruchten Gleitanwendungen sowie Präzisierung der Aufgabenstellung und angewandten Methoden 14 3 Berechnungsmethoden für keramische Werkstoffe 18 3.1 Spannungszustand im keramischen Bauteil 18 3.2 Zulässige Spannung und Sicherheitsbeiwert für keramische Werkstoffe 20 3.3 Lebensdauerbestimmung mittels Messmethoden 24 4 Mechanisches Design eines keramischen Gleitlagers (mechanische Lebensdauer) 26 4.1 Verbindungselement Koppelstange und typische Lastsituationen 26 4.2 Konstruktive Voraussetzungen für eine rein elastische Beanspruchung 27 4.3 Parameterstudien zu konstruktiven Einflussgrößen und deren Auswirkung auf die mechanische Beanspruchung 30 4.3.1 Einfluss der Fertigungsqualitäten des Lagersitzes 31 4.3.2 Einfluss der Gleitlagerbuchsen- und Einbettungssteifigkeit 32 4.3.3 Einfluss der Bolzenballigkeit 36 4.3.4 Einfluss der Einbettungsbauform 36 4.3.5 Einfluss der Lagerbelastung und des Nenndurchmessers 40 4.3.6 Einfluss der Lagerluft 41 4.3.7 Weitere Parameterstudien 42 4.4 Ableitung von Konstruktions- und Werkstoffanforderungen 43 4.5 Experimentelle Festigkeitsuntersuchung 45 4.5.1 Prüfstandsvorrichtungen 46 4.5.2 Proben zur Festigkeitsuntersuchung und Messprogramm 47 4.5.3 Statische und dynamische Tragfähigkeit keramischer Gleitlager 49 5 Design eines fluidfreien und reibwertreduzierten Tribologiesystems (tribologische Lebensdauer) 51 5.1 Allgemeine und keramische Tribologie 53 5.2 Zusammenfassung tribologischer Kennwerte einer Si3N4-Stahl-Paarung 57 5.3 Möglichkeiten zur Reibwert- und Verschleißreduzierung 59 5.4 Experimentelle Analyse des Tribologiesystems 65 5.4.1 Tribologiesystem und Abbruchkriterien 65 5.4.2 Tribologische Proben und Messprogramm 69 5.4.3 Ergebnisse zum Reibwert und zum erzielbaren Gleitweg 74 5.4.4 Verschleißzustände und tribologisches Verhalten 78 5.4.5 Diskussion der tribologischen Ergebnisse 83 6 Berechnungsvorschrift zu rein elastisch beanspruchten Gleitlagerbuchsen nach dem Spannungsminimum 85 7 Zusammenfassung und Diskussion der Ergebnisse 90 8 Ausblick 93 Literaturverzeichnis 95 Anlagenverzeichnis 97
334

Des pieds de la croix à l’art total : Etude des représentations de l’Eglise et de l’art sacré à travers l’ekphrasis huysmansienne / From the foot of the Cross to Gesamtkunstwerk : A study of Church’s and sacred art’s depictions through Huysmans’s ekphrasis

Batto, Yann January 2023 (has links)
The term "ekphrasis" is indisputably problematic. In fact, depending on which definition one might use ekphrastic processes can either be broad, that is extended to any type of description as it was taught in rhetoric treaties during antiquity, or according to its modern definition circumcised to literary representations of works of art. Since ekphraseis are a key feature of Huysmans's work, this study strives to explore their scope through describing the sacred art in the so-called "catholic novels" Huysmans wrote after his religious conversion and the Church's representation that stems from them. This study focuses on two forms of religious art: the plainchant and the architecture. Based on a broad theoretical frame ranging from ekphrasis and hypotyposis figures of speech to intermediality, the study shows that the medieval Church is considered as quintessentially a pluri-medial entity or as Wolf puts it, a "syncretistic medium". Thus, it seems possible to establish a connection between this image of an ideal Church and the notion of Gesamtkunstwerk. Last but not least, this depiction which arises from Huysmans's work sheds light on a broader societal phenomenon that occurred in the transitional period which was the late 19th century, namely a strong interest in medievalism.
335

Including Amish in Agriculture Planning: Opportunities for Integrating Members of the Amish and Plain Communities into Food and Agriculture Planning in Wayne County, Ohio

Hershberger, Jeremy Edward January 2021 (has links)
No description available.
336

Scalable Detection and Extraction of Data in Lists in OCRed Text for Ontology Population Using Semi-Supervised and Unsupervised Active Wrapper Induction

Packer, Thomas L 01 October 2014 (has links) (PDF)
Lists of records in machine-printed documents contain much useful information. As one example, the thousands of family history books scanned, OCRed, and placed on-line by FamilySearch.org probably contain hundreds of millions of fact assertions about people, places, family relationships, and life events. Data like this cannot be fully utilized until a person or process locates the data in the document text, extracts it, and structures it with respect to an ontology or database schema. Yet, in the family history industry and other industries, data in lists goes largely unused because no known approach adequately addresses all of the costs, challenges, and requirements of a complete end-to-end solution to this task. The diverse information is costly to extract because many kinds of lists appear even within a single document, differing from each other in both structure and content. The lists' records and component data fields are usually not set apart explicitly from the rest of the text, especially in a corpus of OCRed historical documents. OCR errors and the lack of document structure (e.g. HMTL tags) make list content hard to recognize by a software tool developed without a substantial amount of highly specialized, hand-coded knowledge or machine learning supervision. Making an approach that is not only accurate but also sufficiently scalable in terms of time and space complexity to process a large corpus efficiently is especially challenging. In this dissertation, we introduce a novel family of scalable approaches to list discovery and ontology population. Its contributions include the following. We introduce the first general-purpose methods of which we are aware for both list detection and wrapper induction for lists in OCRed or other plain text. We formally outline a mapping between in-line labeled text and populated ontologies, effectively reducing the ontology population problem to a sequence labeling problem, opening the door to applying sequence labelers and other common text tools to the goal of populating a richly structured ontology from text. We provide a novel admissible heuristic for inducing regular expression wrappers using an A* search. We introduce two ways of modeling list-structured text with a hidden Markov model. We present two query strategies for active learning in a list-wrapper induction setting. Our primary contributions are two complete and scalable wrapper-induction-based solutions to the end-to-end challenge of finding lists, extracting data, and populating an ontology. The first has linear time and space complexity and extracts highly accurate information at a low cost in terms of user involvement. The second has time and space complexity that are linear in the size of the input text and quadratic in the length of an output record and achieves higher F1-measures for extracted information as a function of supervision cost. We measure the performance of each of these approaches and show that they perform better than strong baselines, including variations of our own approaches and a conditional random field-based approach.
337

”Därför är det viktigt att ta bort en fästing.” : Förkunskaper och behov av information som förutsätts hos modelläsare i två versioner av en webbtext om fästingbett. / “Therefore, it is important to remove a tick.” : The model readers prior knowledge and information need in two versions of one web text about tick bites.

Fjertorp, Emelie January 2022 (has links)
This study analyzes the semiotic resources in two versions of Vårdguiden's web text about tick bites: one longer version and one in easy Swedish. The aim is to identify and compare the prior knowledge and information need of each versions' model reader. This study is theoretically grounded in social semiotics and health literacy. The method consists of three multimodal text analyzes with ideational, interpersonal and textual sub-analyses.  Both versions presupposing several actual, practical and mental prior knowledge of the model reader. The information need of the versions' model reader is both common and separate. Both versions also presupposing that the model reader needs informing, explanatory, instructive and reassuring messages with a multimodal and multi-sequential presentation. The longer version presupposes more comprehensive prior knowledge and larger information needs. The version in easy Swedish though presupposes some prior knowledge which is not assumed in the longer version. For example, it is prior knowledge of how a tick bite looks like and the prior knowledges which is required when photographic close-ups should be interpreted. The version in easy Swedish also and presupposes larger needs for explanations and instructions. The results hinting what the versions presuppose of the empirical reader and prompting a discussion about how the versions high demands for health literacy can impede the reader friendliness. However, the results show that the versions' design creates possibilities for broad groups to assimilate the content. The study highlights some important challenges which are relevant when texts should be adapted to broad groups. / I studien analyseras två versioner av 1177 Vårdguidens text om fästingbett: en längre version och en version på lätt svenska. Syftet är att identifiera och jämföra de förkunskaper och behov av information som förutsätts hos versionernas modelläsare. Studien är teoretiskt grundad i sociosemiotik och hälsolitteracitet. Metoden består av tre multimodala textanalyser med ideationella, interpersonella och textuella delanalyser. Båda versionerna förutsätter flera faktiska, praktiska och mentala förkunskaper hos modelläsaren. Behoven av information hos versionernas modelläsare är dels gemensamma, dels skilda. Båda versionerna förutsätter att modelläsaren behöver informerande, förklarande, instruerande och lugnande budskap som presenteras multimodalt och multisekventiellt. Den längre versionen förutsätter mer omfattande förkunskaper och större behov av information. Versionen på lätt svenska förutsätter dock några förkunskaper som inte förutsätts i den längre versionen. Det är till exempel förkunskaper om hur ett fästingbett ser ut och de förkunskaper som krävs för att kunna tolka fotografiska närbilder. Versionen på lätt svenska förutsätter även att modelläsaren behöver fler förklaringar och instruerande budskap. Resultaten antyder vad versionerna förutsätter hos de empiriska mottagarna och föranleder en diskussion om hur versionernas höga krav på hälsolitteracitet kan hindra brukarvänligheten. Resultaten visar dock att versionernas utformning ger möjligheter för breda grupper att tillgodogöra sig innehållet. Studien belyser några viktiga utmaningar som är relevanta när texter ska mottagaranpassas till breda grupper. / <p>Uppsatsen ingår i kursen språkrådgivning och textvård magisterkurs, 30 hp.</p>
338

Isotope Analysis on the Great Hungarian Plain: An Exploration of Mobility and Subsistence Strategies from the Neolithic to the Copper Age

Giblin, Julia Irene 27 July 2011 (has links)
No description available.
339

Quantitative Ecological and Taphonomic Patterns in Late Cenozoic Mollusk-Dominated Marine Fossil Assemblages

Barbour Wood, Susan L. 27 June 2006 (has links)
Applications in paleontological research are far from being limited to taxonomic collection and identification. Nor is such research limited to working solely on fossil data. Actualistic paleontology is the study of modern or recent organisms and processes to better understand those of the past. The bulk of this body of research falls under the category of actualistic paleontology, and examines geochronological methods and error biases in dating biological specimens ranging in age from modern to thousands of years old. Although such methods are arguably not perfect, error rates of ± a few hundred to few thousand years can be extremely important when considering ecological relationships among both Holocene taxa and time-averaged paleocommunities, but quite diminished when considering implications on more traditional dating techniques for ancient strata. Regardless, understanding implications of time resolution is important in analyses of and comparisons between any biological dataset. The following chapters are united by quantitative and statistical management of data with varying levels of temporal resolution, and represent four manuscripts that either are in press or soon to be submitted for publication. / Ph. D.
340

Undersökning om implementering av återvunna ullfibrer i mattgarn : En jämförande studie om kvalitetens påverkan av återvunnen ull i mattor / Investigation of implementation of recycled wool fibers in carpet yarn

Ogbekene, Edith, Bergelin, Sandra January 2024 (has links)
Ull är en populär fiber och förekommer ofta i mattproduktion. Med hjälp av livscykelanalyser visar ullen vara en av de fibrerna som ligger i toppen av de material som har högst koldioxidutsläpp. Dock finns det en problematik vid beräkning av miljöpåverkan inom ullproduktionen som kan bidra till ett orättvist resultat. Trots det kvarstår faktumet att det finns förbättringar inom ullproduktionen samt att det är viktigt att ta vara på den ullen som annars skulle gått till förbränning. I samarbete med mattföretaget Rugvista undersöker denna studie hur implementering av 60% återvunna fibrer i mattgarn påverkar kvalitén med en målsätting att få in ull i ett cirkulärt flöde. Genom att undersöka detta spanns ett garn med 60% återvunnen ull och 40% konventionell ull på en E-spinner. Syftet var att garnet skulle nå upp de krav som Rugvista ställer på deras garn. Båda garnerna handvävdes därefter i en tvåskaftsbindning med ett inslagsripsutseende och i samma struktur för de skulle kunna bli jämförda med varandra under samma förutsättningar. Garnerna gick därefter igenom ett dragprovstest och de vävda proverna utsattes för ett modifierad martindaletest. Utifrån dragprovstestet påvisade de tillverkade garnet att de krävdes högre kraft för att nå brottspunkten, då majoriteten av protoypgarnerna klarade en kraft på 3500 cN, vilket var max kraften för Rugvistas garn. Dock gick det att se en större variation på brottpunkten till skillnad från Rugvistas garn som var mer enhetligt i deras resultat. I det modifierade martindaletestet gjordes en visuell bedömning på det vävda proverna efter dem hade blivit utsatta för 15 000 varv. Där påvisades referensmaterialet ett bättre resultat då den bevarade sitt utgångs utseende medan prototypen fick noppbildning redan efter 3000 varv samt släppte ifrån sig betydligt mer fibrer. Slutsatsen av studien blev att utifrån testningen visade prototypen att den inte möter den kvalitén som Rugvista ställer på sina mattor. Utmaningen är den korta fiberlängden hos de återvunna ullfibrerna som lätt lossnar från garnet. Studien visar även att de möjligt att tillverka ett tillräckligt starkt garn för att väva mattor i men att det krävs ytterligare forskning för att produktanpassa det till garnets förutsättningar. / Wool is an admired fiber and is frequently utilized in carpet production. According to life cycle analyses (LCA), wool shows to be one of the fibers that ranks highest in carbon dioxide emissions. However, there are challenges when calculating the environmental impact of wool production that contributes to an unfair result. This does not negate the reality that there are some areas within the wool life cycle that needs enhancement, especially when it comes to the utilization of wool that would otherwise have gone to incineration. This study, conducted in collaboration with the carpet company Rugvista, examines how 60% recycled wool fibers in carpet yarn affects the quality with the aim of getting wool into a circular economy. By investigating this, a yarn with 60% recycled wool and 40% conventional wool was spun on an E-spinner. The objective was to produce a yarn that meets Rugvista's quality standards. Both yarns were later handwoven in a weft-faced plainweave structure to allow for a fair comparison. The yarns underwent a tensile strength test, and the woven samples were subjected to a modified Martindale abrasion test. The results from the tensile test, showed that the manufactured yarns required a higher force to reach the breaking point, as the majority of the prototype yarns could withstand a force of 3500 cN, which was the maximum force for Rugvista's yarns. However, the breaking points of the manufactured yarns had a greater variation, unlike Rugvista's yarn, which demonstrated a more consistent result. In the modified Martindale test, visual assessments of the woven samples were conducted after 15 000 cycles. The reference material, Rugvista’s material, retained its original appearance, while the prototype developed a pilling surface after only 3000 cycles and released a remarkable amount of more fibers. The study concluded that the prototype did not meet Rugvista's quality standards for carpets. The primary challenge is the short fiber length of the recycled wool, which tends to detach from the yarn. While the study demonstrates the possibility of producing sufficiently strong yarn for carpet weaving, further research is necessary to optimize the product according to the yarn's characteristics.

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