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Large Force Range Mechanically Adjustable Dampers for Heavy Vehicle ApplicationsBurke, William Churchill Taliaferro 08 July 2010 (has links)
Semi-active dampers utilizing various working principles have been developed for a variety of vehicles. These semi-active dampers have been designed to resolve the ride and handling compromise associated with conventional passive dampers, and increase vehicle stability. This thesis briefly reviews existing semi-active damper designs, including but not limited to MR dampers, before presenting two new prototype semi-active hydraulic dampers. Both prototype dampers are designed to provide a large force range while maintaining easily controllable valve characteristics.
The first of these dampers served primarily as a proof of concept and a means of understanding the dynamics of a disc valve housed inside the main piston. The valve design is presented, along with other information concerning the fabrication of the Initial Prototype damper. Test results are presented and analyzed, and a second iteration of the valve is designed. The Final Prototype damper is a scaled up version of the initial design, with refinements made in piston geometry, internal disc profile, and dynamic seals. This large force range damper is tested and results are compared with existing MR dampers. The Final Prototype damper provides a significantly larger force range when compared with typical MR dampers. Finally, to conclude this research, the vehicle dynamics implications of the Final Prototype damper are discussed and recommendations for further study are made. / Master of Science
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Electrochemical assessment and service-life prediction of mechanically stabilized earth walls backfilled with crushed concrete and recycled asphalt pavementEsfeller, Michael Watts, Jr. 02 June 2009 (has links)
A Mechanically Stabilized Earth (MSE) wall is a vertical grade separation that
uses earth reinforcement extending laterally from the wall to take advantage of earth
pressure to reduce the required design strength of the wall. MSE wall systems are often
prefabricated to reduce construction time, thus improving constructability when
compared with conventionally cast-in-place reinforced wall systems. However, there is a
lack of knowledge for predicting the service-life of MSE retaining wall systems when
recycled backfill materials such as Recycled Asphalt Pavement (RAP) and Crushed
Concrete (CC) are used instead of Conventional Fill Material (CFM). The specific
knowledge missing is how these recycled materials, when used as backfill in MSE wall
systems, affects the corrosion rate of the reinforcing strips. This work addresses this
knowledge gap by providing recommendations for MSE wall systems backfilled with CC
or RAP, and provides a guide to predict the service-life based on corrosion rate test data
obtained from embedding steel and galvanized-steel earth reinforcing strips embedded in
MSE wall systems backfilled with CC, RAP, and CFM. Experimental data from samples
emulating MSE wall systems with steel and galvanized-steel reinforcing strips embedded
in CC and RAP were compared to samples with strips embedded in CFM. The results of
the testing provide data and methodologies that may, depending on the environmental
exposure conditions, justify the use of RAP and CC for the construction of MSE walls. If
these backfill materials are obtained from the construction site, this could provide a
significant cost savings during construction.
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Avaliação de características de qualidade e propriedades funcionais da carne mecanicamente separada de frango tratada com diferentes taxas de dose de radiação ionizante e uso de antioxidantes. / Evaluation of quality characteristics and functional properties of mechanically deboned chicken meats treated with different dose of rates of ionizing radiation and use of antioxidants.Brito, Poliana de Paula 15 August 2012 (has links)
A Carne Mecanicamente separada de Frango (CMSF) pode apresentar elevada carga microbiana, como consequência da contaminação durante o processamento ou falhas durante o processo de evisceração. O processo de irradiação é aceito como uma das mais efetivas tecnologias, quando comparada às técnicas convencionais de preservação, por reduzir a contaminação de microrganismos patogênicos e deterioradores. A irradiação provoca alterações químicas no alimento, uma das principais causas da deterioração da qualidade de produtos cárneos crus ou cozidos, durante o armazenamento refrigerado ou congelado. O objetivo deste estudo foi de avaliar os efeitos de diferentes taxas de dose de radiação ionizante sobre a produção de Substancias Reativas ao Ácido Tiobarbitúrico (TBARS), a cor, as características microbiológicas e sensoriais da CMSF adicionada ou não de antioxidantes, ao longo do armazenamento refrigerado, bem como a avaliação das propriedades funcionais. / The mechanically deboned chicken meat (MDCM) can have a high microbial load, as a result of contamination during processing or failure during the evisceration. The irradiation process is accepted as one of the most effective technologies when compared to conventional techniques of preservation, to reduce contamination of pathogens and spoilage. Irradiation causes chemical changes in food, a major cause of deterioration of quality of raw or cooked meat products during refrigerated storage, frozen. The objective of this study was to evaluate the effects of different dose rates of ionizing radiation on the production of Thiobarbituric Acid Reactive Substances (TBARS), color, microbiological and sensory characteristics of MDCM added or not of antioxidants during storage cooled, and the evaluation of functional properties.
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Coherent and Dissipative Transport in Metallic Atomic-Size ContactsDai, Zhenting 15 November 2006 (has links)
Thin-film niobium mechanically controlled break junctions and resistively shunted niobium mechanically-controlled break junctions were developed and successfully microfabricated. Using these devices, high-stability atomic size contacts were routinely produced and investigated both in the normal and superconducting states. Investigations of the two-level conductance fluctuations in the smallest contacts allowed the calculation of their specific atomic structure. Embedding resistive shunts close to the superconducting atomic-sized junctions affected the coherence of the electronic transport. Finally, point contact spectroscopy measurements provide evidence of the interaction of conduction electrons with the mechanical degrees of freedom of the atomic-size niobium contacts.
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Hybrid microfluidic cooling and thermal isolation technologies for 3D ICsZhang, Yue 08 June 2015 (has links)
A key challenge for three dimensional (3D) integrated circuits (ICs) is thermal management. There are two main thermal challenges in typical 3D ICs. First, in the homogeneous integration with multiple high-power tiers, an effective cooling solution that scales with the number of dice in the stack is needed. Second, in the heterogeneous integration, an effective thermal isolation solution is needed to ‘protect’ the low-power tier from the high-power tier. This research focuses to address these two thermal challenges through hybrid microfluidic cooling and thermal isolation technologies.
Within-tier microfluidic cooling is proposed and demonstrated to cool a stack with multiple high-power tiers. Electrical thermal co-analysis is performed to understand the trade-offs between through silicon via (TSV) parasitics and heat sink performance. A TSV-compatible micropin-fin heat sink is designed, fabricated and thermally characterized in a single tier, and benchmarked with a conventional air-cooled heat sink. The designed heat sink has a thermal resistance of 0.269 K·cm2/W at a flow rate of 70 mL/min. High aspect ratios TSVs (18:1) are integrated in the micropin-fins. Within-tier microfluidic cooling is then implemented in 3D stacks to emulate different heating scenarios, such as memory-on-processor and processor-on-processor.
Air gap and mechanically flexible interconnects (MFIs) are proposed for the first time to decrease the vertical thermal coupling between high-power (e.g. processor) and low-power tiers (e.g. memory or nanophotonics). A two-tier testbed with the proposed thermal isolation technology is designed, fabricated and tested. Compared with conventional 3D integration approach, thermal isolation technology helps reduce the temperature at a fixed location in the low-tier by 12.9 °C. The resistance of a single MFI is measured to be 46.49 mΩ.
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Design of a Mechanically Controllable Break Junction to Measure Quantum Conductance of GoldSaaty, Kara January 2013 (has links)
A mechanically controllable break junction setup was designed, constructed and characterized. The mechanically controllable break junction technique is commonly used for measurement of quantum conductance of metals and single molecule conductance. The technique relies on resistance to external vibrations disrupting the atomic or molecular junctions formed and should be in a low electronic noise environment. Through a series of experiments the setup was found to have high mechanical stability and low electronic noise. The quantum conductance of gold was measured repeatedly and a histogram was plotted showing good agreement with the literature. The results indicate that with modifications, the setup can be used to measure the conductance of single molecule junctions and single molecule thermoelectric properties.
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10Ni-0.1C鋼の加工熱処理中に生じる動的相変態に関する研究 / Dynamic Ferrite Transformation Behavior in 10Ni-0.1C Steel during Thermo-Mechanically Controlled Process趙, 立佳 23 March 2015 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第18987号 / 工博第4029号 / 新制||工||1620 / 31938 / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 辻 伸泰, 教授 白井 泰治, 教授 松原 英一郎 / 学位規則第4条第1項該当
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Nutritive Evaluation of Mechanically-Pressed Canola (Brassica napus L.) Meal for Broiler ChickensBryan, Dervan D S L 19 July 2013 (has links)
Mechanically pressed Brassica napus L. meals’ digestibility nutritional compositions were evaluated with digestibility studies. Two growth trials were conducted identifying the meals’ maximum dietary inclusion level in broiler chicken diets. Heat reduced nutrient digestibility of mechanically pressed black canola meal (MPBCM). Meals with higher residual oil had higher AMEn. Enzyme addition did not affect MPBCM AMEn but increased standardized ileal amino acid digestibility (SIAAD) of meal with high residual oil. Carbohydrase increased AMEn of mechanically pressed yellow canola meal (MPYCM) while lipase generally improved SIAAD. MPBCM with 12 and 17% residual oil can be fed up 15% in the starter and grower diets but at 10% in finisher diet. Mechanically pressed black canola meal (MPYCM) with 12% residual oil should be fed in the starter and finisher diets at 10% and 15% in grower diet. Meal with 17% residual oil should be fed only at 10% in finisher diet. / Masters Thesis
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Instruments for Scoring Pain, Non-Pain Related Distress, Analgesia, and Sedation in Pediatric Mechanically Ventilated Patients and their Efficacy and Effectiveness in Practice: A Systematic ReviewDorfman, Tamara L. Unknown Date
No description available.
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The Role of Mechanically Gated Ion Channels in Dorsal Closure During Drosophila MorphogenesisHunter, Ginger January 2012 (has links)
<p>Physical forces play a key role in the morphogenesis of embryos. As cells and tissues change shape, grow, and migrate, they exert and respond to forces via mechanosensitive proteins and protein complexes. How the response to force is regulated is not completely understood. </p><p>Dorsal closure in Drosophila is a model system for studying cell sheet forces during morphogenesis. We demonstrate a role for mechanically gated ion channels (MGCs) in dorsal closure. Microinjection of GsMTx4 or GdCl<sub>3</sub>, inhibitors of MGCs, blocks closure in a dose-dependent manner. UV-mediated uncaging of intracellular Ca<super>2+</super> causes cell contraction whereas the reduction of extra- and intracellular Ca<super>2+</super> slows closure. Pharmacologically blocking MGCs leads to defects in force generation via failure of actomyosin structures during closure, and impairs the ability of tissues to regulate forces in response to laser microsurgery.</p><p>We identify three genes which encode candidate MGC subunits that play a role in dorsal closure, <italic>ripped pocket</italic>, <italic>dtrpA1</italic>, and <italic>nompC</italic>. We find that knockdown of these channels either singly or in combination leads to defects in force generation and cell shapes during closure. </p><p>Our results reveal a key role for MGCs in closure, and suggest a mechanism for the coordination of force producing cell behaviors across the embryo.</p> / Dissertation
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