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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.
161

Die zeitgenossen und unmittelbaren nachfolger Shakespeares in der Englischen kritik des neunzehnten Jahrhunderts ...

Stolle, Erich, January 1938 (has links)
Inaug.-Diss.--Hamburg. / Lebenslauf. "Literaturverzeichnis: " p. 55-57.
162

Data-Driven, Sparsity-Based Matched Field Processing for Structural Health Monitoring

Harley, Joel B. 01 May 2014 (has links)
This dissertation develops a robust, data-driven localization methodology based on the integration of matched field processing with compressed sensing ℓ1 recovery techniques and scale transform signal processing. The localization methodology is applied to an ultrasonic guided wave structural health monitoring system for detecting, locating, and imaging damage in civil infrastructures. In these systems, the channels are characterized by complex, multi-modal, and frequency dispersive wave propagation, which severely distort propagating signals. Acquiring the characteristics of these propagation mediums from data represents a difficult inverse problem for which, in general, no readily available solution exists. In this dissertation, we build data-driven models of these complex mediums by integrating experimental guided wave measurements with theoretical wave propagation models and ℓ1 sparse recovery methods from compressed sensing. The data-driven models are combined with matched field processing, a localization framework extensively studied for underwater acoustics, to localize targets in complex, guided wave environments. The data-driven matched field processing methodology is then refined, through the use of the scale transform, to achieve robustness to environmental variations that distort guided waves. Data-driven matched field processing is experimentally applied to an ultrasound structural health monitoring system to detect and locate damage in aluminum plate structures.
163

Réalisation de filtres RF à base de cristaux phononiques

Gorisse, Marie 17 November 2011 (has links) (PDF)
Poursuivant l'essor des méta-matériaux micro-ondes et photoniques, les cristaux phononiques, organisations périodiques de matériaux acoustiquement différents présentant notamment des bandes d'arrêt, c'est-à-dire de plages de fréquences pour lesquelles aucun mode ne se propage dans la structure, laissent entrevoir des applications acoustiques hors de portée des technologies existantes. Dans cette thèse, nous visons des réalisations aux fréquences RF afin de viser des applications complémentaires des résonateurs ou des filtres acoustiques largement employés dans le domaine des transmissions sans fil. Nous avons tout d'abord développé un procédé de fabrication simple permettant de réaliser des cristaux phononiques à deux dimensions à l'échelle micrométrique sur membrane piézoélectrique, afin de rendre ces systèmes compatibles avec les composants à ondes de Lamb développés au CEA-LETI pour des applications de filtrage de canal dans des architectures de transmission sans fil faible consommation. Ce procédé a été utilisé pour réaliser des cristaux phononiques, ainsi que des résonateurs à ondes de Lamb, ou à ondes de volume et des structures plus complexes comme par exemple des filtres passe-bande. Une étude paramétrique des composants à ondes de Lamb nous a permis d'affiner notre maîtrise de ces dispositifs, ce qui nous a été utile pour la mise au point des lignes à retard permettant de caractériser les propriétés de transmission acoustique des cristaux phononiques. Du point de vue théorique, un modèle de simulation par éléments finis a été mis en place, dans un premier temps pour dimensionner les structures réalisées et prendre en compte les modifications apportées par la réalisation technologique. Nous avons ensuite réalisé des cristaux phononiques que nous avons caractérisés électriquement et optiquement, en collaboration avec l'Institut FEMTO-ST. Les mesures confirment la présence de bandes d'arrêt, aux fréquences attendues, mais d'une largeur a priori bien supérieure à celle prévue par la simulation. Une étude détaillée des diagrammes de bandes attribue ce phénomène à la présence de bandes sourdes dans le cristal ne pouvant être excitées par les transducteurs utilisés. Cet aspect est d'une importance critique dans le dimensionnement de cristaux phononiques en vue d'une utilisation dans des applications pratiques.
164

Atskirų veislių avių mišrūnų produktyvumo tyrimai / The Research on Hybrid Lambs Productivity after Selective Breeding

Valinčius, Nerijus 19 May 2014 (has links)
Temos aktualumas. Gyvulininkystės sektorius Lietuvoje yra svarbi žemės ūkio sritis. Šio sektoriaus plėtrai šalyje yra palankios gamtinės sąlygos, susiformavusios gyvulių auginimo tradicijos, sukaupta patirtis. Gyvulininkystės sektorius ypač reikšmingas, aprūpinant Lietuvos vartotojus įvairiais maisto produktais bei svarbus Lietuvos eksporto šaltinis. Gyvūninės kilmės produktai taip pat yra svarbi subalansuotos mitybos dalis, - juose gausu žmogaus organizmui reikalingų maisto medžiagų, vitaminų ir mineralų. Gyvulininkystės sektorius yra svarbus maisto pramonei. Mėsos, pieno ir kitų perdirbimo įmonių techninis potencialas sudaro visas galimybes maksimaliai išnaudoti gyvulininkystės sektoriaus išteklius ir sudaryti ekonomines prielaidas šio sektoriaus plėtrai. Daugelio veislių avių genetinis mėsinių savybių potencialas yra aukštas, todėl tinkamai jas panaudojant galima gauti mišrūnus ėriukus, kurie pasižymės ypač geromis mėsinėmis savybėmis ir aukštos biologinės vertės mėsa. Darbo objektas – avių mišrūnai. Darbo tikslas – išanalizuoti Sufolkų ir Vilšyrhornų, Lietuvos juodgalvių ir Vilšyrhornų, Sufolkų ir Kamerūno, Lietuvos juodgalvių ir Kamerūno genotipo mišrūnų ėriukų produktyvumą. Darbo uždaviniai:1. Išanalizuoti ėriavedžių, kergiant jas skirtingų veislių avinais, reprodukcinius rodiklius. 2. Ištirti skirtingo genotipo mišrūnų ėriukų augimo spartą ir mėsines savybes. 3. Ištirti skirtingo genotipo mišrūnų ėriukų mėsos kokybę. 4. Įvertinti skirtingo genotipo mišrūnų ėriukų... [toliau žr. visą tekstą] / The relevance of the topic. Sector of animal husbandry in Lithuania is an important part of agriculture. For the enlargement of this sector there are favourable nature conditions, formed animal growing traditions, accumulated experiences. Sector of animal husbandry is significant in supplying various food products for the Lithuania consumers and an important source for the export. Moreover, products from animal meat are essential part of the healthy balanced diet. Meat contains many various food materials, vitamins and minerals needed for the organism of human being. Furthermore, the sector of animal husbandry is important for the food industry. Technical potential of meat, milk and other product processing companies create all the opportunities for maximizing resources of the animal husbandry sector and to create economical assumptions for the growth of this sector. The potential of meat characteristics of many various sheep’s is high, therefore while using it smartly it is possible to obtain hybrid lambs, which distinguish oneself with exceptionally good meat characteristics and high biological value meat. The object of the thesis is hybrid lambs. The goal of the thesis is to analyze Suffolk (S) and Wiltshire horn (WH), Lithuania black head (LBH) and Wiltshire horn, Suffolk and Cameroon(C), Lithuania black head and Cameroon genotype hybrid lambs productivity. Objectives of the thesis: 1. To analyze ewes reproduction indicators while pairing them with different breed rams... [to full text]
165

NDT Applications for the Assessment of Asphalt Pavements, Plate Thickness, and Steel-Grout Coupling

Wu, Yen Chieh January 2012 (has links)
Nondestructive testing (NDT) uses different wave propagation modes to evaluate the internal structure of materials, revealing internal damage such as corrosion and fracturing that cannot be detected by traditional methods. Civil infrastructures are considered high priority assets in Ontario and Canada because of their value, high consequence of failure, and the continual influence of aging effects. Unexpected failure of infrastructure not only costs more than planned replacements but also results in increased safety risks. The in-situ condition assessment of civil infrastructure is critical for the successful implementation of maintenance and safety programs. Therefore, reliable nondestructive methods of inspection are required for the implementation of economical and efficient maintenance and asset management programs. Continuing technological developments in data collection, acquisition equipment, and data processing techniques have provided useful applications of nondestructive methods in many engineering fields. Among the many applications, this research study examines three applications of nondestructive testing in civil engineering: (1) condition assessment of construction joints in asphalt pavements, (2) average thickness evaluation of steel pipes, and (3) void and debonding detection in grouted steel tanks. The study on asphalt focuses on the improvement of the coupling system between the transducers and the asphalt surface, and the development of a new data processing technique to reduce user input and increase the reliability of the condition assessment of longitudinal joints. The current wavelet transmission coefficient (WTC) method requires user input, making the automatic data processing difficult. In the WTC method, the coupling between the transducers and the asphalt surface requires the use of epoxy and aluminum plates. This procedure is not practical for testing in-service roads. A new coupling mechanism using polyurethane foam to provide a spring action on the transducers and calibrated weights to generate a compression force was developed and showed good results, reducing the testing time by up to 50%. A new and robust data analysis methodology, called instantaneous transmission coefficient (ITC), is proposed based on measured instantaneous frequencies and damping ratios. The main advantage of the ITC procedure is that it can be performed automatically, reducing user input. A laboratory scale asphalt slab is used to evaluate the new methodology. Results show good agreement between the WTC and ITC measurements for both jointed and joint-free areas. The second study investigates the feasibility of the multichannel analysis of surface waves (MASW) technique for the evaluation of the average wall thickness of steel pipes. Electromagnetic NDT methods, such as the eddy current and the remote field testing, are common tools for thickness measurement of conductive materials. However, these methods give only localized results where measurements are made, making the process time consuming and inaccurate for assessing the full cross-sectional area of the pipe. Lamb waves have been used previously in the evaluation of steel pipes; however, the existing techniques require prior calibration to a theoretical wave mode, and their accuracy decreases with the length of the pipe evaluated due to wave attenuation effects. Preliminary results show the capability of the MASW test for providing reliable thickness information. The measured dispersion curves include information of fundamental modes and the higher modes, providing an improved characterization of the medium. Thicknesses between 3.2 mm and 12.7 mm are tested with an error of less than 2%. The third study explores the detection of voids in a steel tank filled with lightweight grout. A joint analysis of surface waves and Lamb waves is used for void detection and the identification of debonding conditions in a laboratory scale model of a steel tank filled with grout. Different configurations of the MASW method are conducted using an instrumented hammer (large wavelengths, 10 cm < λ < 25 cm) and a 50 kHz piezoelectric transmitter (small wavelengths, 5 cm < λ < 9 cm) as sources. The attenuation coefficient computed from the Fourier spectra of the measured signals indicates that the presence of a void has an effect on the propagation of the wave. The comparison between experimental and theoretical dispersion curves show that mainly Lamb waves are generated during the testing of the steel tank; thus, detecting the debonding conditions between the steel plate and the grout. Lamb modes are used successfully for detecting the presence of a void beneath the steel wall. The laboratory measurements are effective in the detection of the void, showing amplitudes up to 50% higher, likely because the deformation of the wall is attenuated by the grout.
166

Byron and "scribbling women" Lady Caroline Lamb, the Brontë sisters, and George Eliot /

Millstein, Denise Tischler. January 1900 (has links)
Thesis (Ph. D.)--Louisiana State University, Baton Rouge, 2007. / Title from document title page.
167

Effect of crossbreeding and reproduction rate on sensory, physical and chemical quality of lamb and mutton

Schmidt, Dewcille 03 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Please refer to fulltext for abstract. / AFRIKAANSE OPSOMMING: Sien asb volteks vir opsomming
168

Estudo da suplementação de ovelhas, idade á desmama e sistemas de terminação de cordeiros machos inteiros sobre a qualidade da carne

Bonagurio, Sarita [UNESP] 07 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-07Bitstream added on 2014-06-13T20:24:29Z : No. of bitstreams: 1 bonagurio_s_dr_botfmvz.pdf: 1804420 bytes, checksum: 9db1235e1aa2ef0e33f2bce2025b1f7f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O experimento teve como objetivo avaliar o efeito da suplementação da ovelha 30 dias antes do parto, a idade à desmama (45 ou 60 dias) de cordeiros machos e o sistema de terminação em confinamento (com dieta completa ou somente feno) e em pasto, sobre perfil de ácidos graxos do tecido muscular. As dietas fornecidas aos animais foram formuladas segundo as recomendações do NRC (1985). O perfil de ácidos graxos foi feito no músculo Tríceps brachii. Os parâmetros de abate foram 30 kg de peso vivo ou 150 dias de idade. Os cordeiros terminados no confinamento, alimentados com feno, foram abatidos pela idade e os demais cordeiros pelo peso vivo. Os ácidos graxos C15:0, C16:0, C17:0, C16:1, C18:1 e C18:3 diferiram entre os sistemas de terminação dos cordeiros. Os cordeiros da dieta completa tiveram maiores valores de C16:0, C16:1 e C18:1, e os cordeiros alimentados com feno e do pasto maiores teores de C18:3. A dieta dos cordeiros alterou o perfil de ácidos graxos. / The objective of this work was to evaluate the effect of sheep supplementation 30 days before parturition, age of male lambs at weaning (45 or 60 days old) and termination system in confinement (with full diet or hay only) and in pasture over the fatty acid profile of the muscle tissue. The diets provided to the animals were formulated as recommended by NRC (1985). The fatty acid profile was performed on Tríceps brachii muscle. Slaughter parameters were 30 kg of live weight or 150 days old. Lambs terminated in confinement, fed with hay, were slaughtered by age and the remaining ones, by live weight. Fatty acids C15:0, C16:0, C17:0, C16:1, C18:1 and C18:3 were different between lambs termination systems. Lambs fed with full diet presented higher C16:0, C16:1 and C18:1 values and the ones fed with hay and grass presented higher C18:3 values. Lambs diet affected the fatty acid profile.
169

Manta de Petrolina - PE: uma alternativa para agregar valor à carne ovina / Manta (Boned and Salted meat) of Petrolina/PE: An Alternative to Adding Value to lamb meat

Pedrosa, Nely de Almeida 20 December 2010 (has links)
Made available in DSpace on 2015-04-17T14:49:46Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1782828 bytes, checksum: 696c70ec90d13fdad0f2e84ca001161c (MD5) Previous issue date: 2010-12-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The manta ovina , a lamb meat product, is produced from the boning, salting and drying of lamb carcasses. It is a typical salted meat product from the region of Submédio do Vale does Rio São Francisco, with reference the city of Petrolina, Pernambuco Brazil. The manta ovina was evaluated in order to obtain information and establish identity patterns and product quality. In the present study was described the process, identified the potential hazards to product safety and evaluated the physicochemical (color, pH, Aw, PPC, FC, moisture, ash, proteins and lipids), microbiological (total and fecal coliforms, halophilic bacteria, Salmonella sp and Staphylococcus aureus) and sensory (appearance, aroma, flavor, texture and overall assessment) quality of manta ovina . The study was performed in three restaurants which are part of the gastronomic complex called Bodódromo , located in the city of Petrolina, in the state of Pernambuco, Brazil. The values of pH (6.22 ± 0.22), water activity (0.97 ± 0.02) moisture (69.86 ± 2.26) and protein (22.23 ± 1.96) classified the manta ovina as a perishable product, and consequently, requiring the use of other preservation methods, such refrigeration, combined with salt. The manta ovina presented 4.14 ± 2.23% fats, and about 60% of minerals (3.19 ± 0.57%) are in the form of chlorides (1.93 ± 0.64). This percentage reflects the use of salt, essential ingredient used during the processing of the product. Losses during the cooking varied significantly (P ≤ 0.05), between 14.8% and 22.4%. The measurement of texture, through instrumental (3.18 ± 0.12 Kgf) and sensory evaluation (7.44) showed that the manta ovina is a soft meat product. In sensory evaluation no significant differences (P ≥ 0.05) were detected among the samples served in the three restaurants. The mean scores were above seven points on a scale ranging from 1 to 9. It showed that the manta ovina is a meat product with appearance, flavor, tenderness and taste that pleased the consumer. Microbiological evaluation indicated the absence of Salmonella; on the other hand, Staphylococcus species showed a count of exceeding the limits prescribed by Brazilian law. This result reinforces the need for implementation and maintenance of hygienic practices to ensure a safety product. It was observed that the process used during the manta ovina preparation, involves the application of a traditional technology, salting, associated with an innovative technique of deboning, which is peculiar in region, resulting in a meat product with characteristic of great potential exploration. The results reveal a similarity in nutritional quality, physical, sensory and microbial mats, showed the similarity of production procedures used in the three restaurants. It reinforces the need to standardize the process and creation of technical regulation of identity and quality for this meat product derived. / A manta ovina, alimento proveniente da desossa, salga e secagem de carcaças de ovinos típico da região do Submédio do Vale do Rio São Francisco, tendo como referência a cidade de Petrolina PE - Brasil, foi avaliada com o objetivo de obter-se informações, que embasam o estabelecimento de padrões de identidade e qualidade deste produto. Na presente pesquisa foi descrito o processo, identificados os perigos potenciais para segurança do produto e avaliada a qualidade físico-química (cor, pH, Aa, PPC, FC, umidade, cinzas, proteínas e lipídeos), microbiológica (coliformes totais e termotolerantes, bactérias halófilas, Salmonella sp e Staphylococcus aureus) e sensorial (aparência, aroma, sabor, textura e avaliação global) de mantas ovinas provenientes de três estabelecimentos produtores em Petrolina - PE. Os valores médios de pH (6,22 ±0,22), atividade de água (0,97±0,02), umidade (69,86±2,26) e proteínas (22,23±1,96) da manta ovina a caracterizam como um produto perecível, sendo necessário o uso de outros métodos de conservação combinados com o sal, como a conservação pelo frio. A manta apresenta 4,14 ± 2,23% de lipídeos e, cerca de 60% dos minerais encontrados (3,19 ±0,57%), estão na forma de cloretos (1,93 ±0,64), estando este fato diretamente associado ao uso do sal, ingrediente indispensável para a elaboração do produto. As perdas por ocasião da cocção variaram significativamente (P≤0,05) entre 14,79 % e 22,39 %. Tanto a avaliação instrumental (3,18±0,12 kgf) quanto a avaliação sensorial (7,44) da textura revelaram que a manta é um produto macio que agrada o consumidor. Na avaliação sensorial não houve diferença significativa (P≥0,05) entre as amostras servidas nos três restaurantes para os atributos sensoriais, cuja pontuação obteve escores médios acima de sete, em escala que variou de 1 a 9, mostrando que a manta é um produto cárneo com aparência, aroma, maciez e sabor que agradam o consumidor. A avaliação microbiológica indicou ausência de Salmonella sp, porém apresentou contagem de Staphylococcus que ultrapassam os limites preconizados pela legislação brasileira, o que reforça a necessidade de aplicação e manutenção de práticas higiênicas que garantam a segurança do produto. Observou-se que o processo envolve a aplicação de uma tecnologia tradicional na região Nordeste, que se utiliza da salga, método milenar de conservação, porém com uma técnica inovadora de desossa peculiar da região, obtendo-se um produto cárneo característico de grande potencial de exploração. Os resultados encontrados revelam a semelhança na qualidade nutricional, física, sensorial e microbiológica das mantas, demonstrando a similaridade dos métodos de produção adotados nos três estabelecimentos estudados, o que fortalece a necessidade de padronização do processo e criação de um regulamento técnico de identidade e qualidade para este produto cárneo derivado.
170

Towards a precise measurement of the He'+ 2S lamb shift

Burrows, Simon Adam January 2001 (has links)
No description available.

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