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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.
71

Bass Is My Religion: Syncretic Spirituality and Navigating the Potential for Misappropriation Among Participants in Electronic Dance Music Culture

Backfish-White, Daniel 01 January 2021 (has links)
At electronic dance music events in the United States, artists and attendees tend to appropriate religious and spiritual sounds, images, and dress, especially from India but also from elsewhere, to varying degrees. This project explicates the effects of adopting religious symbology, ethos, and atmosphere in the music and culture of EDM, specifically in bass music culture. It argues that although individual participants may adopt aspects of religious traditions in ways they perceive as authentic, the potential for misappropriation still exists. In other words, EDM culture creates opportunities for misappropriation that individual participants navigate in order to construct their own individual forms of spirituality in relation to the live music experience and EDM culture at large. Utilizing a set of seven interviews with individuals who have close ties to the EDM community, this project explores the ways that attendees navigate conversations about cultural appropriation, specifically in the bass music community. A set of common attitudes, opinions, and beliefs forges a syncretic spirituality among these seven interviewees, which inform how these individuals navigate conversations about appropriation in the EDM community. In addition to these seven interviews, three case studies that focus on specific artists who spearhead specific subscenes frame this project: the psychedelic downtempo duo Desert Dwellers, the multiethnic trap artist TroyBoi, and the cult dubstep DJ Bassnectar. Synthesizing ideas by these seven interviews with previous EDM scholarship and specific cases within these communities, I conclude that as artists and attendees negotiate meanings with one another, they must ultimately choose to justify their appropriation, often by claiming a syncretic sense of spirituality, or to avoid association with it entirely.
72

Theoretical And Experimental Investigation Of Residual Stresses In Electric Discharge Machining

Ekmekci, Bulent 01 January 2004 (has links) (PDF)
Electric Discharge Machining (EDM) is a process for eroding and removing material by transient action of electric sparks on electrically conductive materials immersed in a dielectric liquid and separated by a small gap. A spark-eroded surface is a surface with matt appearance and random distribution of overlapping craters. It is mechanically hard and stressed close to ultimate tensile strength of the material and sometimes covered with a network of micro cracks. The violent nature of the process leads a unique structure on the machined surface and generates residual stresses due mainly to the non-homogeneity of heat flow and metallurgical transformations. An extensive experimental study is presented to explore the surface and sub-surface characteristics together with the residual stresses induced by the process. Layer removal method is used to measure the residual stress profile in function of depth beneath. A finite element based model is proposed to determine residual stresses and compared with the experimental results. The residual stress pattern is found to be unchanged with respect to machining parameters. Thus, a unit amplitude shape function representing change in curvature with respect to removal depth is proposed. The proposed form is found as a special form of Gauss Distribution, which is the sum of two Gaussian peaks, with the same amplitude and pulse width but opposite center location that is represented by three constant coefficients. In each case, agreement with the proposed form is established with experimental results. Results have shown that these coefficients have a power functional dependency with respect to released energy.
73

Styly elektronické taneční hudby v rámci české scény / Styles within the Czech scene of electronic dance music

TOMANOVÁ, Šárka January 2012 (has links)
This diploma thesis is focused on the topic of electronic dance music and its genre classification within Czech music scene. The main part of the thesis defines seven primary genres of EDM from the historical and musical perspective, and consequently it divides them into the subgenres that the audience can meet on the Czech dance floors most frequently. Moreover, the thesis describes the origin, evolution as well as the current situation of Czech EDM. The thesis also concerns with the differences among the subgenres by means of the drum pattern notation and sonic samples.
74

Optimalizace řídicích parametrů EDM stroje / Optimization of EDM process control parameters

Prokeš, Tomáš January 2021 (has links)
The dissertation thesis is focused on the optimization of control parameters of an EDM machine; the subject of optimization is cutting speed and surface topography. The first part of the thesis contains a research study on the technology of electrical discharge machining with the attention paid to the optimization methods use for control parameters of this process. The second part of the thesis is focused on real application of knowledge gained from studied sources. Here, a design of experiment aim at optimizing the parameters of the EDM machine is designed and carried on to maximize the cutting speed with the highest possible surface quallity. The result of the work is to build adequate regression models and find the optimal setting of machine control parameters.
75

Drátové elektroerozivní obrábění při výrobě nástrojů pro dřevoobrábění / Wire electrical discharge machining at production of tools for working of wood

Sedláček, Jiří January 2008 (has links)
My thesis is aimed at the application of wire electical discharge machining technology in the production of woodworking tools. All of this in the conditions of Vydona company. There is a theory of machining method plus a well-aranged division of cutter tools for wood in the introduction. The practical part describes in detail the procedur of cutting shaped plate out of tungsten carbide. As a result of the technical and at the same time the economic evaluation is an establishment of hourly rate for machine.
76

Nekonvenční technologie elektroerozivního drátového řezání. / Unconventional Technology of Wire Electrical Discharge Machining.

Svoboda, Jiří January 2010 (has links)
This thesis deals with technology of electric discharge machining with emphasis on application of the principle of material removal on wire cut electric discharge machine. The main part is concentrated on wire cut electric discharge machining in terms of a small tool making shop. The goal of the thesis is to create a wire cut electric discharge machining workplace in the company with a focus on the production of cutting tools. The thesis defines requirements for each component of cutting tools and strategies for their machining. Machining of model part and subsequent technical - economic evaluation is included in the final part.
77

Technologie elektrojiskrového drátového řezání / Technology of wire electrical discharge machining

Brázda, Radim January 2013 (has links)
This master´s thesis deals with unconventional technology of wire electrical discharge machining. There are described the principles and essence of electrical discharge machining and the principles related to wire electrical discharge machining with emphasis on the application of this technology in terms of medium-sized engineering company. There is also described the complete assembly of technolgy wire cutting and machining on wire cutter Excetek V 650. Then in the work there are statistically evaluated parameters precision machined surfaces, specifically to the belt pulley 116-8M-130. At the end of the work there is the technical-economic evaluation that addresses the hourly cost of machining on wire cutter Excetek V 650.
78

Wire Electric Discharge Machining of Curvilinear Swept Surfaces / WEDM of Curvilinear Swept Surfaces

Gabriel, Salomon C. January 2016 (has links)
Fir tree root forms are one way to retain turbine blades in turbine disks. These features are ruled surfaces that span the entire thickness of the disk and are usually machined by broaching. With increasing use of new heat resistant and difficult-to-machine materials, mechanical machining methods exhibit severe problems with tool wear and surface integrity. To mitigate these problems, thermal material removal processes such as Wire Electrical Discharge Machining (WEDM) are being considered in the aerospace industry. Developments in turbine design have led to a root form geometry in the form of an arc across the thickness of the disk in order to decrease the contact stress by increasing the contact area between blade and disk. A curved surface such as this cannot be produced by conventional WEDM as it is not a ruled surface. A novel WEDM process is being developed where an arc shaped curve is formed from an axially moving wire to allow for the production of such curved surfaces. / Thesis / Master of Applied Science (MASc) / Turbine blades are attached to turbine disks with specially shaped, straight slots called Fir Tree Root Forms (FTRF) that can be cut with broaching tools. Broaches wear out quickly because the disk is made of very difficult to cut material and the aerospace industry is starting to use Wire Electric Discharge Machining (WEDM), instead of broaching, to cut these slots since it can easily cut the material used. New turbine disk designs have curved slots, which can not be cut with a straight broach or wire, and a new process is therefore being developed which uses an arc-shaped wire to cut the desired curved shapes.
79

AN EXERGETIC APPROACH TO AIRCRAFT THERMAL MANAGEMENT SYSTEM ANALYSIS AND DESIGN OPTIMIZATION

Marcin Glebocki (13140390) 22 July 2022 (has links)
<p> Design and optimization of aircraft thermal management systems (TMS) is typically conducted by considering a single system architecture at steady-state conditions, using per?formance metrics such as bleed air flow rate, fuel burn flow rate, or total system mass. However, when trying to increase the overall performance of a legacy system or analyzing new system architectures, it can be difficult to identify how individual component or sub?system changes will propagate throughout the overall TMS. In this thesis, new knowledge and tools are presented that will advance the use of exergy-based design techniques for next generation aircraft thermal management systems (TMS). This is motivated by the fact that exergy destruction is a quantity that can be calculated for any subsystem or component, regardless of energy domain or function. The relationship between exergy destruction min?imization (EDM) and conventional design metrics is investigated and quantified. This is performed through the use of a steady-state analysis and by leveraging a high fidelity model of a complex TMS. It is shown that exergy destruction is not only sensitive to individual component parameters in a manner consistent with conventional performance metrics, but that due to its generalizability, it also captures how changes in one subsystem propagate throughout the overall TMS. Specifically, through a design case study, it is shown that minimizing system-wide exergy destruction rate (without an engine model) yields a similar engine fuel burn rate as when fuel burn is minimized directly, but also results in a signif?icantly lower system mass. Building on these results, a transient design and analysis tool for TMS is developed using a graph theoretic approach. The tool is used on a case study of an air cycle machine (ACM) and on an architecture enumeration case study for a notional TMS. The transient exergy-based analysis is shown to provide insight into how efficiently energy is used at a component level, and captures the differences in thermal performance between architectures. </p>
80

Optimisation de l'usinage par le procédé d'électroérosion à fil des alliages de titane et des matériaux composites à base de titane appliqués à l'aéronautique / Optimization of machining by wire electric discharge machining process of the titanium alloys and titanium based composites applied to the aeronautics

Ezeddini, Sonia 17 December 2018 (has links)
L’usinage par électroérosion est un procédé d’enlèvement de matière par fusion, vaporisation et érosion, réservé aux matériaux conducteurs et semi-conducteurs.Il peut être utilisé pour usiner les métaux et alliages, les aciers trempés, les alliages céramiques, les carbures métalliques, certaines céramiques et même des matériaux plus durs tels que le diamant polycristallin. La pièce ainsi chauffée voit ses caractéristiques mécaniques chuter et modifier, ce qui augmente son usinabilité. Les travaux réalisés ont porté sur l'influence de l'usinage par électroérosion à fil sur; l'intégrité de surface, l'usinabilité, la productivité et la précision de procédé, de plusieurs matériaux, tels que, le titane pur, l'alliage de titane Ti-6Al-4V, le composite intermétallique à base Ti-Al, le composite Ti17 et le composite Ti6242.En usinage par électro-érosion à fil, et plus précisément en finition, le procédé est caractérisé par un débit de matière, une largeur de kerf, un durcissement superficiel, une zone affectée thermiquement et un état de surface variant en fonction de plusieurs paramètres tels que, le courant de décharge, le temps d’impulsion, la tension d’amorçage, la vitesse de coupe, la pression d'injection de lubrifiant et la tension de fil.Toutefois, il s’agit d’une étude d’optimisation et de modélisation empirique des conditions de coupe des matériaux composites à base métallique et des alliages de titane, afin de maitriser et d'améliorer l'intégrité de surface usinée, d'augmenter la productivité et de perfectionner la précision du procédé. Par la suite, atteindre les exigences de la qualité et de la sûreté de fonctionnement des pièces aéronautiques.Dans cette étude, on a utilisé des méthodes de type Plan d'expériences, méthode de Taguchi et la Méthodologie des surfaces de réponses pour le calage et le contrôle des paramètres de l’usinage par électroérosion à fil, et ses conditions opératoires. / EDM machining is a process for the removal of material by melting, spraying and erosion, which is reserved for conductive and semiconductor materials.It can be used for machining metals and alloys, hardened steels, ceramic alloys, metal carbides, some ceramics and even harder materials such as polycrystalline diamond. The heated part has its mechanical characteristics drop, which increases its machinability. The work carried out focused on the influence of WEDM machining on surface integrity, machinability, productivity and process precision, of several materials: pure titanium, Ti6Al4V alloy, composite intermetallicTi-Al based, Ti17 composite and Ti6242 composite.In ripping, and more precisely in finishing, the process is characterized by a flow of material,kerf width, surface hardening, heat affected zone and surface condition varying with discharge current, pulse time and voltage, cutting speed, lubricant injection pressure and wire tension.In fact, the machining conditions of metal-based composite materials and titanium alloys have been modeled and optimized to improve machined surface integrity, increase productivity, and improve process accuracy. Subsequently, meet the quality and safety requirements of aeronautical parts.Methods such as Experimental Design, Taguchi and Surface of Response were used for calibration and process control parameters and operating conditions.

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