Ultra-wideband (UWB) communication new technology with ability to share the FCC allocated frequency spectrum, large channel capacity and data rate, simple transceiver architecture and high performance in noisy environments. Such communication advantages have paved the way for emerging wireless technologies such as wireless high definition video streaming, wireless sensor networks and more. This thesis examines orthogonal frequency coded surface acoustic wave (SAW) correlators for use in advanced UWB communication systems. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for UWB spreading of data. The use of OFC spectrally spreads a PN sequence beyond that of CDMA because of the increased bandwidth; allowing for improved correlation gain. The transceiver approach is still very similar to that of the CDMA approach but provides greater code diversity. Use of SAW correlators eliminates many of the costly components that are needed in the IF block in the transmitter and receiver, and reduces much of the signal processing requirements. The OFC SAW correlator device consists of a dispersive OFC transducer and a wideband output transducer. The dispersive filter was designed using seven contiguous chip frequencies within the transducer. Each chip is weighted in the transducer to account for the varying conductance of the chips and to compensate for the output transducer apodization. Experimental correlator results of an OFC SAW correlation filter are presented. The dispersive filter is designed using seven contiguous chip frequencies within the transducer. SAW correlators with fractional bandwidth of approximately 29% were fabricated on lithium niobate (LiNbO3) having a center frequency of 250 MHz and the filter has a processing gain of 49. A coupling of modes (COM) model is used to predict the experimental SAW filter response. Discussion of the filter design, analysis and measurements are presented. Results are shown for operation in a matched filter correlator for use in an UWB communication system and compared to predictions.

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En las últimas dos décadas, han surgido diferentes tecnologías acústicas para aplicaciones biosensoras como alternativas a tecnologías de detección bien establecidas ¿acústicas o ópticas¿ como son la Microbalanza de Cuarzo (QCM, por sus siglas en inglés) y la Resonancia de Plasmón de Superficie (SPR, de sus siglas en inglés). En la primera parte de este documento se revisan dichas tecnologías alternativas para aplicaciones en medio líquido. Como resultado de esta revisión, se determina que los dispositivos de onda acústica superficial Love (LW, de sus siglas en inglés) son los más prometedores y viables para conseguir el principal objetivo de esta Tesis, que es establecer una comparativa en las mismas condiciones entre inmnosensores desarrollados con la tecnología seleccionada en esta tesis y los inmunosensores desarrollados con QCMs de Alta Frecuencia Fundamental (HFF-QCM, por sus siglas en inglés). Después de esta revisión se presenta el estado del arte de los dispositivos LW en su aplicación como biosensores, así como una discusión de las tendencias y retos actuales de este tipo de sensores. Posteriormente se reúne la información más actualizada sobre aspectos de diseño, principios de operación y modelado de estos sensores. Algunos aspectos de diseño son estudiados y probados para establecer el diseño final de los dispositivos LW. Previamente a su fabricación, también se realizan simulaciones para modelar el comportamiento del dispositivo elegido previamente a su fabricación. Posteriormente, se describe la fabricación del dispositivo así como la celda de flujo diseñada para trabajar con el dispositivo en medios líquidos. Adicionalmente, un sistema electrónico de caracterización, previamente validado para sensores QCM, se adapta para sensores LW. Como resultados, se valida el sistema electrónico para caracterizar los sensores LW fabricados y montados en la celda de flujo y, finalmente, se desarrolla un inmunosensor para la detección del pesticida carbaril que se compara con otras tecnologías inmunosensoras. / In the last two decades, different acoustic technologies for biosensors applications have emerged as promising alternatives to other better established detection technologies ¿ acoustic or optic ones- such as traditional Quartz Crystal Microbalance (QCM) and Surface Plasmon Resonance (SPR). The alternative acoustic technologies for in liquid measurements are reviewed in this manuscript. Surface Acoustic Wave (SAW) Love Mode or Love Wave (LW) sensors are determined to be the most promising and viable option to work with for achieving the main aim of this Thesis. Such aim is the development of a LW immunosensor for its comparison with the same application based on High Fundamental Frequency-QCM (HFF-QCM) sensors and under the same conditions. Consequently, the state-of-the-art of LW devices for biosensing is provided and a discussion about the current trends and future challenges of these sensors is presented. In order to start working with suitable LW devices, upto- date information regarding the design aspects, operation principles and modeling of such devices is gathered. Some design aspects are explored and tested to establish the design of the final LW device. Different simulations for modeling the chosen device behavior are carried out before its fabrication. Later, the device fabrication is described. Next, to start working with the fabricated device in liquid media, a flow cell is designed and implemented. In addition, an electronic characterization system, previously validated for QCM sensors, is adapted and tested for the fabricated LW device. As results, the adapted electronic characterization system is validated for LW devices mounted in the fabricated flow cell and, finally, a LW-based immunosensor for the determination of carbaryl pesticide was developed and compared with other immunosensor technologies. / Rocha Gaso, MI. (2013). Analysis, implementation and validation of a Love mode surface acoustic wave device for its application as sensor of biological processes in liquid media [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/32492

Three studies were conducted to better understand the current status of the industry and create a design process and taxonomy. Study 1 assessed current industry usage of dust control technologies and stakeholder perceptions in the concrete and masonry trades. Study 2 was similar but assessed emission control technologies in the asphalt roofing trade. Study 3 used the information from studies 1 and 2 to select a tool for further evaluation. The handheld cutoff concrete saw was chosen. An iterative design process was utilized to evaluate the saw. The design process and subsequent usability inspection engendered a taxonomy, or set of design recommendations can be applied to large handheld powered tools. / Ph. D. / Three studies were conducted to better understand the current perceptions of risks associated with the construction industry and create a process for designing tools that mange the associated risks. Study 1 and Study 2 assessed current industry use of technologies for managing health hazards present when working in the concrete, masonry, and asphalt roofing industries; and the interested party’s perceptions of the industries. Study 3 used the information from Studies 1 and 2 to select a tool for further evaluation. The handheld cut-off concrete saw was chosen. An iterative design process was utilized to evaluate the saw. The design process and subsequent usability test created a set of design recommendations which can be applied to large handheld powered tools. A telephone survey was conducted to assess the concrete, masonry, and asphalt roofing industries. The survey measured decision makers’ perceptions of health hazard control technologies. Finally, it assessed business factors affecting adoption of the control technologies and projects specifying the use of health hazard control technologies. The results show the concrete and masonry industries understand the risks associated with working in the industry and are more likely to adopt health hazard management technologies. The asphalt roofing industry is unsure if they view heated asphalt to be a health hazard and are more resistant to adopting current technologies. There are more projects specifying the use of control technologies in concrete and masonry and a decreasing number of projects are specifying the use of control technologies in asphalt roofing. The business factors for adopting technologies are the same across industries, specifically worker safety and government regulation. Those looking to have an impact on the construction industry should focus on the concrete and masonry industries over asphalt roofing. In the final study, a design process and guidelines were created for large handheld powered equipment. The researcher used an iterative design process whose goal was to better equip industry with a dust control device, specifically a vacuum based system for the gasoline powered handheld cut-off concrete saw. Results from Studies 1 and 2 influenced the direction of the design process. The design did not yield a prototype fit for testing, so the researcher assessed the usability of a commercially available system. The results were transformed into design guidelines for anyone interested in creating better hazard controls for similar power tools. The guidelines created are: have clear symbols, efficiently provide feedback, provide feedback when attaching parts, make attaching parts easy, have efficient design to reduce dangers inherent with the tool, increase visibility, reduce overexposure to dangers, ensure it is easy to move, and enable a wide variety of users to be able to use the saw. The process used to design the prototype can be used to design similar large handheld powered tools. The design process starts with looking at how the tool is currently used, then brings stakeholders together to discuss the problem, then create prototypes, and finally test the prototypes for performance and/or usability which will create the design guidelines.

Muchas personas se preguntan por qué veo películas tan “feas” y siempre respondo lo mismo: “Las veo porque me asustan, se me escarapela el cuerpo; por ende, me gustan. Me gusta la sensación del miedo y de la repugnancia”. Lo que más atrae de estas películas son las emociones diversas que provocan en el espectador. Sin embargo, eso no es lo único que me interesa, sino también los personajes que encarnan estas emociones y, sobre todo, el discurso sobre la justicia y la ambivalencia. La construcción ambivalente los vuelve más complejos y genera en el espectador una explosión de emociones. Parece ser que estas personalidades ficticias tienen un gusto por lo abyecto y eso tiene un motivo. Es por esto que he querido dirigir mi gusto por lo abyecto del discurso de estas películas y por los personajes antihéroes hacia el análisis de una de las sagas que más me ha gustado: Saw. En ella confluye el terror, el gore y lo complejo del personaje antihéroe que tanta acogida ha tenido en los últimos años. Mi trabajo se centra en un análisis de la temática de la justicia cruel y cómo está representada tanto en lo visual como en lo conceptual. En otras palabras, cómo los elementos visuales ayudan a exacerbar la crueldad que se muestra en la justicia del psicópata de Saw; además de indagar más sobre los motivos y las consecuencias que tienen sus actos, implicados también en la explicación de la justicia cruel del personaje.

The symposium “Optimization of wood-based process chains in Eastern Africa” linked research on wood product processing, from the tree grower in the remote rural to the final consumers and markets in the urban centers. Senior and junior researchers from distinguished institutions in Ethiopia, Tanzania, Uganda and Germany jointly participate, were inspiring and learning from each other. The symposium presented a platform to extend the well-established project cooperation with East African towards technological and engineering disciplines as well as energy economics. It served to further develop the just started, DAAD and BMBF-funded project WoodCluster, which was implemented by East African universities and the Institute of International Forestry and Forest Products at TU Dresden. The overall objective of the symposium was to create an interdisciplinary network of scientists with contact to the private sector to further develop and upscale wood-based process chains in decentralized structures, for example based on small scale farm forest enterprises in Africa.:Preface 3 Contents 5 Session 1: Country specific situation analysis 6 Some insights in the wood sector of Ethiopia 6 Optimization of wood-based process chains in eastern Africa 6 Adaption of forest operations to local conditions and social needs 7 Sawmilling industry cluster analysis for sawn wood supply and demand in selected regions of Tanzania 8 Session 2: Innovative technologies for processing of plantation timber 8 Wood properties of fast-growing plantation timber and related processing strategies 8 Innovations in wood processing and in wood products 9 ‘Appropriate’ Technology Options for Timber Production in Uganda’s Plantation Forests 10 Present needs and trends of the woodworking industry 10 Wood in best form: innovative construction materials 11 Browsing for small scale wood processing technology on the trade fair Ligna 11 Project proposal: Integrated Wood Processing Subsidiary 12 Session 3: Innovative technologies for small scale wood based energy systems 12 Pyrolysis of wood: process, technical aspects and efficiency 12 Sustainable Wood Based Energy for Households in Developing Countries: Considering Wood Pellet as a Viable Alternative Household Energy Source in Ethiopia 13 Combined heat-power-charcoal conversion for African rural households: Available advanced models 14 Changing perspectives of German international Cooperation on problems and solutions for wood/bio-mass based energy conversion systems in Africa 15 Analysis of a wood chip gasifier in a thermochemical test area 15 Small Scale Wood Gas Cogeneration: Why, when, where? 16 Session 4: Innovation and technology transfer 16 Upgrading forest cluster and forest value chains for regional development 16 Assessing sustainability of small and micro enterprises 17 Knowledge systems and knowledge transfer 18 Innovation and technology transfer 18 Conclusions 19 Contact details of participants 20

The cutting links on chainsaws needs to be sharpened regularly to retain its sharpness. The most effective way is to use a machine wheel grinder. However, due to high friction there is a high risk of tempering the steel and damaging the sustainability to wear, resulting in a dull cutting edge. In order to develop a grinding method that produces a good result every time, a series of parameters were tested in order to determine which combination of these generated the best grinding results. With all parameters established the results shows that the attributes of each grinding wheel are the main parameter controlling the grinding result. This project investigates the attributes of different grinding wheels and their impact on grinding results. By comparing the energy each grinding wheel uses to perform the same amount of work, each grinding wheels suitability is rated based on its performance.   The calculations and the results from the analyses and tests show which of the grinding wheels performed the work with the lowest amount of increased energy.

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-09-15T18:12:49Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Rodrigo Medeiros da Silva.pdf: 1734954 bytes, checksum: bb3851360da8bd727dad4bc7836a5534 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-09-15T18:13:10Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Rodrigo Medeiros da Silva.pdf: 1734954 bytes, checksum: bb3851360da8bd727dad4bc7836a5534 (MD5) / Made available in DSpace on 2014-09-15T18:13:10Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Rodrigo Medeiros da Silva.pdf: 1734954 bytes, checksum: bb3851360da8bd727dad4bc7836a5534 (MD5) Previous issue date: 2013-11-10 / This study aimed at assessing the carcass and meat traits as well as fatty acid profile of crossbred steers of European or zebu genotypic predominance, finished in feedlot, fed diets with high percentage of concentrate (80%) containing different levels of grounded millet grain as replacement for grounded corn grain (0, 33, 66 and 100%). We allocated in 16 collective pens 45 steers with European predominance and 44 with zebu-predominance, with average initial weight of 317.8 and 320.7 kg, respectively, and average age of 21 month. At the end of the finishing period, we slaughtered six animals of each genetic group, randomly chosen within each level of replacement of corn by millet grain. The experimental design was completely randomized with treatments in a 4x2 factorial arrangement using six replicates. The replacement of corn grain by millet grain did not significantly affect slaughter weight (480.4 kg), hot carcass weight (259.5 kg), carcass yield (54.1%) and subcutaneous fat thickness (3.95 mm). Steers with predominant European genotype showed significantly higher values for slaughter weight (507.6 vs. 453.3 kg), hot carcass weight (269.6 vs. 249.3 kg) and Longissimus dorsi area (65.34 vs 56.83 cm2); however, they had lower carcass yield (53,2 vs. 55,00%). Increasing the proportion of millet in the diet linearly increased the arachidic (C20:0), heneicosanoic (C21:0), linolenic (C18:3 n-3) and di-homo linolenic (C20:3 n-6) fatty acids. European steers meat showed less content of myristic (C14:0), heneicosanoic (C21:0) and linolenic (C18:3 n-6) fatty acids. The total concentration of saturated (45.2%), monounsaturated (41.2%) and polyunsaturated (8.7%) fatty acids and, monounsaturated/saturated (1.09) and polyunsaturated/saturated (0.18) relationship were not affected by the factors studied. Millet grain can be used in replacement of corn grain for finishing steers since it does not change carcass traits of economic interest. The increase in the percentage of millet grain in the diet of European and zebu crossbred steers improves the ratio between n-6/n-3 fatty acids. / Objetivou-se avaliar as características de carcaça, da carne e perfil de ácidos graxos da carne de novilhos inteiros mestiços com predominância genotípica européia ou zebuína, alimentados em confinamento com dietas com elevada proporção de concentrado (80%) contendo diferentes níveis de grão de milheto moído em substituição ao grão de milho moído (0, 33, 66 e 100%). Foram confinados, em 16 baias coletivas, 45 novilhos com predominância genotípica européia e 44 novilhos com predominância genotípica zebuína, com peso médio inicial de 317,8 e 320,7 kg, respectivamente, e 21 meses de idade. Ao final do período de confinamento foram abatidos seis animais de cada grupo genético, escolhidos aleatoriamente dentro de cada nível de substituição do grão de milho pelo de milheto. O delineamento experimental foi o inteiramente casualizado, com os tratamentos em arranjo fatorial 4x2, utilizando seis repetições. A substituição do grão de milho pelo grão de milheto não influenciou significativamente os pesos de abate (480,4 kg), de carcaça quente (259,5 kg), rendimento de carcaça quente (54,1 %) e espessura de gordura subcutânea (3,95 mm). Novilhos com predominância genotípica européia apresentaram valores significativamente superiores para peso de abate (507,6 vs 453,3 kg), peso de carcaça quente (269,6 vs 249,3 kg) e área do músculo Longissimus dorsi (65,34 vs 56,83 cm2), porém, foram inferiores no rendimento de carcaça quente (53,2 vs 55,0 %). O avanço da percentagem do grão de milheto na dieta elevou linearmente a participação dos ácidos graxos araquídico (C20:0), heneicosanóico (C21:0), linolênico (C18:3 n-3) e di-homo linolênico (C20:3 n-6). Novilhos E apresentaram carne com menor (P<0,05) teor de mirístico (C14:0), heneicosanóico (C21:0) e linolênico (C18:3 n-6) do que novilhos Z. A concentração total de ácidos graxos saturados (45,2%), monoinsaturados (41,2%) e poliinsaturados (8,7%) e, a relação monoinsaturados/saturados (1,09) e poliinsaturados/saturados (0,18) não foram alterados pelos fatores estudados. O grão de milheto pode ser utilizado em substituição ao grão de milho, pois não altera as principais características de carcaça de interesse econômico de novilhos terminados em confinamento. O aumento da percentagem de grão de milheto na dieta de novilhos mestiços europeus ou zebuínos melhora a relação entre os ácidos graxos n-6/n-3.

We studied the possibility of achieving an order of magnitude reduction in the energy dissipation needed to write bits in perpendicular magnetic tunnel junctions (p-MTJs) by simulating the magnetization dynamics under a combination of resonant surface acoustic waves (r-SAW) and spin-transfer-torque (STT). The magnetization dynamics were simulated using the Landau-Lifshitz-Gilbert equation under macrospin assumption with the inclusion of thermal noise. We studied such r-SAW assisted STT switching of nanomagnets for both in-plane elliptical and circular perpendicular magnetic anisotropy (PMA) nanomagnets and show that while thermal noise affects switching probability in in-plane nanomagnets, the PMA nanomagnets are relatively robust to the effect of thermal noise. In PMA nanomagnets, the resonant magnetization dynamics builds over few 10s of cycles of SAW application that drives the magnetization to precess in a cone with a deflection of ~45⁰ from the perpendicular direction. This reduces the STT current density required to switch the magnetization direction without increasing the STT application time or degrading the switching probability in the presence of room temperature thermal noise. This could lead to a pathway to achieve energy efficient switching of spin-transfer-torque random access memory (STT-RAM) based on p-MTJs whose lateral dimensions can be scaled aggressively despite using materials with low magnetostriction by employing resonant excitation to drive the magnetization away from the easy axis before applying spin torque to achieve a complete reversal.

Planar two-dimensional (2-D) nanostructured indium oxide (InOx) and one-dimensional (1-D) tin oxide (SnO2) semiconductor metal-oxide layers have been utilised for gas sensing applications. Novel layered Surface Acoustic Wave (SAW) based sensors were developed consisting of InOx/SiOxNy/36°YXLiTaO3, InOx/SiNx/SiO2/36°YXLiTaO3 and InOx/SiNx/36°YXLiTaO3 The 1 µm intermediate layers of silicon oxynitride (SiOxNy), silicon nitride (SiNx) and SiO2/SiNx matrix were deposited on lithium tantalate (36°YXLiTaO3) substrates by r.f. magnetron sputtering, electron-beam evaporation and plasma enhanced chemical vapour deposition (PECVD) techniques, respectively. As a gas sensitive layer, a 100 nm thin layer of InOx was deposited on the intermediate layers by r.f. magnetron sputtering. The targeted gases were ozone (O3) and hydrogen (H2). An intermediate layer has multiple functions: protective role for the interdigital transducers' electrodes as well as an isolating effect from InOx sensing layer, thereby improving the sensor performance. The developed SAW sensors' exhibited high response magnitudes with repeatable, reversible and stable responses towards O3 and H2. They are capable of sensing concentrations as low as 20 parts-per-billion for O3 and 600 parts-per-million for H2. Additionally a conductometric type novel sensing structure of SnO2/36°YX LiTaO3 was also developed by depositing a thin layer of SnO2 nanorods by PECVD. The gas sensing performance exhibited repeatable, reversible, stable responses towards NO2 and CO. The surface morphology, crystalline structure and preferred orientation of the deposited layers were investigated by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). A polycrystalline, oxygen deficient non-stoichiometric InOx with grain sizes of 20-40 nm was revealed. The 1-D nanostructures were characterised by Transmission Electron Microscopy (TEM) showing nanorods with needle-like shape , diameters of 10-20 nm a t the top and 30-40 nm at the base as well as a preferential growth orientation of [ ] on the LiTaO3 substrate. The developed sensors are promising for O3, H2 and CO sensing.