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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.
151

Den Digitala Framgången : Skillnaden på Två Fiol Plug-ins

Netzler, Philip January 2021 (has links)
Digitala instrument och digitala medel gör det idag lätt att skapa musik med hjälp avdatorn. Men hur långt har dessa virtuella instrument kommit? Denna uppsats jämför tvåolika fiolsimuleringar (Plug-ins) mot varandra, utifrån en riktig inspelad fiol somreferens. Uppsatsen ämnar undersöka vilken av dessa som upplevs som bäst och mestrealistisk. Detta bedöms utifrån tre personer som spelar klassiska instrument och hararbetat med musik på olika sätt, samt att de fortfarande är verksamma inom musiken.Dessa personer har jobbat eller jobbar som instrumentlärare för klassiska instrumentsamt det de själva utövat eller fortfarande utövar musik i form av orkester osv. Dentidigare forskningen visar på att simuleringar har fått bra resultat men att det fortfarandefinns mycket förbättringar att göra. För att få fram empirin spelades en riktig fiol in, föratt sedan användas som referens till två simuleringar av samma melodi och spelsätt iden mån det var möjligt att åstadkomma. Sedan sammanställdes ett lyssningstest somvar ett så kallat dubbelblindtest, där de tre deltagarna jämförde dessa två mot varandrautifrån referensen. Efter detta gjordes intervjuer där de fick svara mer djupgående påfrågor som reflekterar de svar de lämnat vid lyssningstestet. Resultatet visar att dessatvå fungerar att ha i bakgrunden medan en riktig fiol har fokuset som solo instrument.Det framkommer att simuleringarna saknar vissa övertoner och att en viss botten ochfärg som medföljer ett riktigt instrument saknas. Däremot så var alla tre öppna för att dekan användas i bakgrunden till skivinspelningar eller liknande.
152

Nonlinear Constrained Component Optimization of a Plug-in Hybrid Electric Vehicle

Yildiz, Emrah Tolga 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Today transportation is one of the rapidly evolving technologies in the world. With the stringent mandatory emission regulations and high fuel prices, researchers and manufacturers are ever increasingly pushed to the frontiers of research in pursuit of alternative propulsion systems. Electrically propelled vehicles are one of the most promising solutions among all the other alternatives, as far as; reliability, availability, feasibility and safety issues are concerned. However, the shortcomings of a fully electric vehicle in fulfilling all performance requirements make the electrification of the conventional engine powered vehicles in the form of a plug-in hybrid electric vehicle (PHEV) the most feasible propulsion systems. The optimal combination of the properly sized components such as internal combustion engine, electric motor, energy storage unit are crucial for the vehicle to meet the performance requirements, improve fuel efficiency, reduce emissions, and cost effectiveness. In this thesis an application of Particle Swarm Optimization (PSO) approach to optimally size the vehicle powertrain components (e.g. engine power, electric motor power, and battery energy capacity) while meeting all the critical performance requirements, such as acceleration, grade and maximum speed is studied. Compared to conventional optimization methods, PSO handles the nonlinear constrained optimization problems more efficiently and precisely. The PHEV powertrain configuration with the determined sizes of the components has been used in a new vehicle model in PSAT (Powertrain System Analysis Toolkit) platform. The simulation results show that with the optimized component sizes of the PHEV vehicle (via PSO), the performance and the fuel efficiency of the vehicle are significantly improved. The optimal solution of the component sizes found in this research increased the performance and the fuel efficiency of the vehicle. Furthermore, after reaching the desired values of the component sizes that meet all the performance requirements, the overall emission of hazardous pollutants from the PHEV powertrain is included in the optimization problem in order to obtain updated PHEV component sizes that would also meet additional design specifications and requirements.
153

Powertrain Sizing and Energy Usage Adaptation Strategy for Plug-in Hybrid Electric Vehicles

Chanda, Soumendu 12 May 2008 (has links)
No description available.
154

Modeling, Simulation & Implementation of Li-ion Battery Powered Electric and Plug-in Hybrid Vehicles

Mantravadi, Siva Rama Prasanna 15 August 2011 (has links)
No description available.
155

Understanding Performance--Limiting Mechanisms in Li-ION Batteries for High-Rate Applications

Thorat, Indrajeet Vilasrao 29 April 2009 (has links) (PDF)
This work presents novel modeling and experimental techniques that provide insight into liquid-phase mass transport and electron transfer processes in lithium-ion batteries. These included liquid-phase ionic mass transport (conduction and diffusion), lithium diffuion in the solid phase and electronic transport in the solid phase. Fundamental understanding of these processes is necessary to efficiently design and optimize lithium-ion batteries for different applications. To understand the effect of electrode structure on the electronic resistance of the cathode, we tested power performance of cathodes with combinations of three different carbon conductivity additives: vapor-grown carbon fibers (CF), carbon black (CB) and graphite (GR). With all other factors held constant, cathodes with a mixture of CF+CB were found to have the best power-performance, followed by cells containing CF only and then by CB+GR. Thus, the use of carbon fibers as conductive additive was found to improve the power performance of cells compared to the baseline (CB+GR). The enhanced electrode performance due to the fibers also allows an increase in energy density while still meeting power goals. About one-third of the available energy was lost to irreversible processes when cells were pulse-charged or discharged at the maximum rate allowed by voltage-cutoff constraints. We developed modeling and experimental techniques to quantify tortuosity in electrolyte-filled porous battery structures (separator and active-material film). Tortuosities of separators were measured by two methods, AC impedance and polarization-interrupt, which produced consistent results. The polarization-interrupt experiment was used similarly to measure effective electrolyte transport in porous films of cathode materials, particularly films containing lithium iron phosphate. An empirical relationship between porosity and the tortuosity of the porous structures was developed. Our results demonstrate that the tortuosity-dependent mass transport resistance in porous separators and electrodes is significantly higher than that predicted by the oft-used Bruggeman relationship. To understand the dominant resistances in a lithium battery, we developed and validated a model for lithium iron phosphate cathode. In doing so we considered unique physical features of this active material. Our model is unusual in terms of the range of experimental conditions for which it is validated. Various submodel and experimental techniques were used to find physically realistic parameters. The model was tested with different discharge rates and thicknesses of cathodes, in all cases showing good agreement, which suggests that the model takes into account physical realities with different thicknesses. The model was then used to find the dominant resistance for the tested cathodes. The model suggests that the inter-particle contact resistance between carbon and the active-material particles was a dominant resistance for the tested cathodes.
156

Software supported hazards identification for Plug & produce systems

Mosa, Waddah January 2022 (has links)
This work proposed a new automated hazard identification (AHI) approach for Pluge&Produce systems. After going through related standards and research works, the required inputs for automated hazard identification were determined. Then, software was presented to demonstrate using these inputs to perform AHI. This software can identify the resource and the emergent hazards. A new approach for identifying the emerging hazards was proposed.This approach uses the concepts of skill types and lookup tables to cover the wide variety of possible hazards when resources work together. Then display all identified hazards in a Hazard Identification Table (HIT). The proposed HIT is designed to support the persons working in risk reduction by drastically reducing the time needed for hazard identification and preparing them to proceed to the next steps in risk analyses.
157

The little engine that could: Characterization of noncanonical components in the speed-variable flagellar motor of the symbiotic soil bacterium Sinorhizobium meliloti

Sobe, Richard Charles 07 June 2022 (has links)
The bacterial flagellum is a fascinating corkscrew-shaped macromolecular rotary machine used primarily to propel bacterial cells through their environment via the conversion of chemical potential energy into rotational power and thrust. Flagella are the principal targets of complex chemotaxis systems, which allow microbes to navigate their habitats to locate favorable conditions and avoid harmful ones by continuous sampling of environmental compounds and cues. Flagella serve as surface and temperature sensors, mediators of host cell adherence by bacterial pathogens and symbionts alike, and important virulence factors for disease-causing microbes. They play several essential roles in accelerating the foundational stages of biofilm formation, during which bacteria build highly intricate microbial communities with increased resistance to predation and environmental assaults. Flagellum-mediated chemotaxis has broad and impactful implications in fields of bioremediation, targeted drug delivery, bacterial-mediated cancer therapy and diagnostics, and cross-kingdom horizontal gene transfer. While the core structural and functional components of flagella have been well characterized in the closely related enteric bacteria, Escherichia coli and Salmonella typhimurium, major departures from this paradigm have been identified in other diverse species that merit further investigation. Many bacteria employ additional reinforcement modules to surround and stabilize their more powerful flagellar motors and provide increased contact points in the inner membrane, the peptidoglycan sacculus, and, in Gram-negative bacteria, the outer membrane. Additionally, the soil-dwelling bacterium Sinorhizobium meliloti exhibits marked distinctions in the regulation, structure, and function of its navigation systems. S. meliloti is a nitrogen-fixing symbiont of the agronomically valuable leguminous plant, Medicago sativa Lucerne, and uses its coupled chemotaxis and flagellar motility systems to search for host plant roots to colonize. Following root colonization, the bacterium converts to a nitrogen-fixing factory for the plant and the combined influences of this symbiosis can quadruple the yields of the host. This dissertation is aimed at delivering a thorough representative overview of the processes facilitating bacterial flagellum-mediated chemotaxis and motility. Chapter 1 describes the interplay between chemotaxis and flagellar motility pathways as well as the structure, function, and regulation of these systems in several model bacteria. Particular emphasis is placed on the comparison of flagellar systems from the soil-dwelling legume symbiont, Sinorhizobium meliloti with other model systems, and a brief introduction is provided for its primary counterpart, the agronomically valuable legume, Medicago sativa, more commonly referred to as alfalfa. Chapter 2 embodies the first report of a flagellar system to require two copies of a protein known as FliL for its function. FliL is found in all bacterial flagellar systems reported to date but is only essential for some to drive motility. The more conserved copy of the protein has retained the title of FliL and several experiments to assay the proficiency of flagellar motor function revealed that in the absence of FliL swimming is essentially abolished as is the presence of flagella on the cell body. Flagellar motor activity and swimming proficiency of mutants lacking the FliL-paralog MotF was nearly as abysmal as those without FliL but flagellation was essentially normal indicating distinct roles for the two proteins. FliL is implicated in initial stator recruitment to the motor while MotF was found to serve as a power or speed modulator. A model to accommodate and explain the roles of these proteins in the flagellar motor of S. meliloti is provided. Chapter 3 links a never-before characterized flagellar protein, currently named Orf23, to a role in promoting maximum swimming velocity and perhaps stator alignment with the rotor in a peptidoglycan-dependent manner. The loss of LdtR, a transcriptional regulator of peptidoglycan-modification genes, caused defects in swimming motility that are restored only by removal of Orf23 or by replacing a nonpolar glycine with a polar serine in the periphery of stator units. Bioinformatics analyses, immunoblotting, and membrane topology reporter assays revealed that Orf23 is likely embedded in the inner membrane and that the remainder of the protein extends into the periplasm. Building on findings from Chapter 2, Orf23 is anticipated to influence stator positioning through interactions with MotF, FliL, and/or stator units directly. The chapter is concluded with the description of future experiments aimed to more thoroughly characterize Orf23. Altogether, this work increases the depth and breadth of knowledge regarding the composition and function of the speed-variable bacterial flagellar motor. We have identified several components required for stator incorporation and function, as well as an accessory component that improves stator performance. A wise society will draw inspiration from these fascinating and powerful machines to inform new technologies to achieve modern goals including targeted drug delivery, bioremediation, and perhaps one day our own exploration. / Doctor of Philosophy / Bacteria are small autonomous single-celled organisms capable of existing and thriving in highly diverse environments. Motility is achieved by these organisms in various ways, but the most common approach is to produce one or more corkscrew-shaped propeller systems known as flagella that are constructed upon and anchored within the wall of the bacterial cell. Rotation of these propellers relies on power converters known as stators to transform the flow of ions down self-produced gradients into useful rotational energy. This process can be likened to the way that the stored energy of water behind a dam can be harnessed and used to power hydroelectric generators. While the core components of flagellar motors are well conserved and understood among distantly related bacteria, billions of years of evolution and refinement of additional structures have allowed bacteria to accommodate swimming in diverse habitats with e.g. low nutrient availability or high viscosity. Here we describe the discovery and characterization of additional components in the flagellar motor system of the soil-dwelling bacterium Sinorhizobium meliloti to navigate soil environments. We report the first identification of a flagellar motor that requires two copies of a pervasive flagellar motor protein known as FliL and have named the more distinct version of the protein MotF. We found that FliL is required for the power converter components to install into the motor and that MotF is necessary to activate them. Next, we identify another motor component, Orf23, that is dispensible for motility but appears to be required to achieve maximum swimming velocity and may serve to shift the motor into a "higher gear". We find that disruption of a regulator of cell wall modification systems leads to defects in motility that are only restored when Orf23 is removed or when the power converter is modified. Ideas are proposed for how FliL, MotF, and Orf23 are integrated into the motor and may contribute to stator function. An advanced understanding of the mechanisms governing flagellar motor structure and function will provide avenues for the improvement of bacteria-based agricultural improvements, development of optimized bacteria-mediated drug delivery systems, bioremediation techniques, and more.
158

Design of an Integrated Battery Charging System for both Wired and Wireless Charging for Battery Electric and Hybrid Vehicles

Elshaer, Mohamed A. January 2020 (has links)
No description available.
159

Understanding the Material Flow Path of the Friction Stir Weld Process

Sanders, Johnny Ray 13 May 2006 (has links)
In the friction stir welding (FSW) process, heat and mechanical work are coupled to produce a solid state weld. The process variables are pin tool rotation speed, translational weld speed, and downward plunge force. The strain-temperature history of a metal element at each point on the cross-section of the weld is determined by the process variables plus the individual flow path taken by the particular filament of metal flowing around the tool and ending on that point. The strain-temperature history determines the properties of a metal filament on the weld cross-section. To control the mechanical properties, the strain-temperature history must be carefully controlled. Indirect estimates of the flow paths and the strain-temperature histories of filaments comprising friction stir welds can be made from a model, if the model provides sufficient information. This paper describes experimental marker studies designed to trace the metal flow streamlines as influenced by variations in the process parameters.
160

M-CSF and GM-CSF induce human monocytes to express either pro- or anti-angiogenic factors

Eubank, Tim January 2003 (has links)
No description available.

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