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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.
611

Mentální a ontologická simulakra: ne-racionalita a ne-reálno v dílech Philipa K. Dicka / Mental and Ontological Simulacra: Non-Rationality and Non-Reality in Works by Philip K. Dick

Kudrna, David January 2020 (has links)
This thesis offers a model for the underlying architecture of the narrative reality in science-fiction works by Philip K. Dick, arguing that Dick's fictional worlds are grounded in the pervasive metamorphosis - the overarching perception of the shifting - of the narrative fabric operating under the conditions of non-rationality and non-reality. The hyphenated coinages conveniently stand for the paradigms of the reality and mental configurations in PKD subverting the seemingly natural dichotomizing oppositions and hierarchies of the real/unreal and the rational/irrational. Bringing in Gilles Deleuze's ontology of difference, this thesis explains the non-rationality and non-reality of Dick's worlds in Deleuzian terms as, firstly, inducing the perception of fictional reality as realizing the innate potential of being by the perpetual becoming of being in multiplicity and, secondly, engendering - in the vein of Deleuzian simulacra - the impossibility of apprehending and categorizing fictional reality unequivocally. The thesis considers and evaluates the underlying assumptions and claims common to various approaches to the subject of reality in PKD's fictions in order to provide the essential context for the following development of the theoretical basis for non-rationality and non-reality shifting....
612

Liquid Natural Gas : A study of the environmental impact of LNG in comparison to diesel / Flytande Naturgas : En studie om LNG:s klimatpåverkan i jämförelse med diesel

Edfors, Jonas, Bremberg, Robin January 2021 (has links)
Liquefied Natural Gases (LNG) has been an alternative fuel in the marine industry for several years, but lately, the amount of ships that have been powered by methane has increased a lot. Some of the reasons for this is because LNG does not contain any sulfur and releases less nitrogen oxides than traditional maritime fuels. In this essay, LNG will be compared to diesel from an environmental perspective with focus on CO2 emissions and its equivalents. International Maritime Organization (IMO) implemented Energy Efficiency Design Index (EEDI) requirements that adjusts how much CO2 is allowed in the exhaust gas per produced kilowatt-hour (kWh). However, these requirements will increase in intervals in the future, the next one is coming 2022 for specific ship types. The method that is used to compare the fuels is Mole-calculations for LNG as well as diesel, then calculate the amount of carbon dioxide (CO2) and its equivalents they release. The results show that under optimal conditions, LNG was the superior choice. However, the maritime industry might have a problem with the requirements that will be introduced to greenhouse gas (GHG) emissions in 2050. / Flytande Naturgas (LNG) har under flera år funnits som ett alternativt bränsle inom sjöfarten, men på senare tid så har skeppen som drivs av metan ökat markant. En anledning till detta är att LNG innehåller inget svavel samt släpper ut mindre NOX jämfört med traditionella bränslen. I denna uppsats så kommer LNG att jämföras mot diesel ur ett klimatperspektiv med fokus på koldioxidutsläpp och dess ekvivalenter. International Maritime Organisation (IMO) har infört Energy Efficiency Design Index (EEDI) krav som justerar hur mycket CO2 man får släppa ut per kilowattimme (kWh), dessa krav kommer dessutom att öka i flertalet intervaller i framtiden, varav nästa intervall redan sker i 2022 för speciella fartygstyper. Metoden som användes för att jämföra bränslena var att beräkna mol-innehållet för både LNG samt diesel, sen från den beräknade data se hur mycket koldioxid (CO2) inklusive ekvivalenter de släppte ut. Resultatet visade att under optimala förutsättningar så var LNG ett klart bättre alternativ än diesel. Däremot så kan sjöfarten ha ett problem inom framtiden från de krav som berör växthusgaser som kommer att ställas från och med 2050.
613

Asfaltocementový beton / Open-graded asphalt concrete filled with a special cement grout

Hruška, Lukáš January 2012 (has links)
Aim of this thesis is the usage of the open-graded asphalt concrete filled with a special cement grout in the road structures. Thesis defines the main concrete properties and explains related legislation and norms that apply. In addition, laboratory design of asfalt mixtures and a tree kind mortal filler and possibilities of mortal filler pigmentation are dealth with. Finally, thesis evaluates the results from various laboratory tests that were performed on the specimens made from final mixtures.
614

ワイヤレス多機能無線ホルダーシステムを用いた加工現象のモニタと診断に関する研究 / ワイヤレス タキノウ ムセン ホルダー システム オ モチイタ カコウ ゲンショウ ノ モニタ ト シンダン ニカンスル ケンキュウ

松田 亮, Ryo Matsuda 22 March 2019 (has links)
近年,IoTに基づく「つながる工場」に関する技術開発が着目され,日本の次世代の製造業を支えるために,新しい研究開発が求められている.特に機械加工の現場では,異常検知や適応制御のために加工現象を精確かつリアルタイムにモニタできる技術が必要とされている.そこで,マシニングセンタなどの工作機械において,回転工具の加工中に多チャンネルで各種の物理量を切削点近傍にてモニタ可能な無線多機能ホルダを開発し,様々な工具,加工方法を対象にその有効性を示した. / Currently, a smart monitoring technology has been attracting particular attention in the factory automation fields regarding the Internet of things (IoT). Particularly in the machining site, the technology of monitoring the processing phenomenon in precision and real-time is required for abnormality detection or adaptive control. Then, we developed a novel tool holder equipped with a wireless communication function to monitor the tool temperature and vibrating accelerations near the cutting point during a tool rotating operation, and we showed effectiveness for various tools and processing method. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
615

CRYSTAL PLASTICITY OF PENTAERYTHRITOL TETRANITRATE (PETN)

Jennifer Oai Lai (17677422) 24 April 2024 (has links)
<p dir="ltr">We investigate the crystal plasticity and shock response of single crystal and polycrystalline pentaerythritol tetranitrate (PETN) using mesoscale finite element simulations. The model includes the Mie-Grüneisen Equation of State and a single crystal plasticity model. Simulations with single crystals with different orientations are tested using our plasticity model under shock compression to explore shear stress and slip. Parameters regarding the Mie-Grüneisen Equation of State are also verified in various orientations from 0.50 to 1.75 km/s. A polycrystalline PETN sample with varying grain sizes and orientations are subjected to shock loading with impact velocities ranging from 0.25 to 0.75 km/s. We study how differences in shock orientation affect slip and stress in PETN at different shock strengths.</p>
616

SHEAR RHEOMETRY PROTOCOLS TO ADVANCE THE DEVELOPMENT OF MICROSTRUCTURED FLUIDS

Eduard Andres Caicedo Casso (6620462) 15 May 2019 (has links)
<p></p><p>This doctoral dissertation takes the reader through a journey where applied shear rheology and flow-velocimetry are used to understand the mesoscopic factors that control the flow behavior of three microstructured fluids. Three individual protocols that measure relative physical and mechanical properties of the flow are developed. Each protocol aims to advance the particular transformation of novel soft materials into a commercial product converging in the demonstration of the real the chemical, physical and thermodynamical factors that could potentially drive their successful transformation. </p> <p> </p> <p>First, this dissertation introduces the use of rotational and oscillatory shear rheometry to quantify the solvent evaporation effect on the flow behavior of polymer solutions used to fabricate isoporous asymmetric membranes. Three different A-B-C triblock copolymer were evaluated: polyisoprene-<i>b</i>-polystyrene-<i>b</i>-poly(4-vinylpyridine) (ISV); polyisoprene-<i>b</i>-polystyrene-<i>b</i>-poly(<i>N</i>,<i>N</i>-dimethylacrylamide) (ISD); and polyisoprene-<i>b</i>-polystyrene-<i>b</i>-poly(<i>tert</i>-butyl methacrylate) (ISB). The resulting evaporation-induced microstructure showed a solution viscosity and film viscoelasticity strongly dependent on the chemical structure of the triblock copolymer molecules. </p> <p> </p> <p>Furthermore, basic shear rheometry, flow birefringence, and advanced flow-velocimetry are used to deconvolute the flow-microstructure relationships of concentrated surfactant solutions. Sodium laureth sulfate in water (SLE<sub>1</sub>S) was used to replicate spherical, worm-like, and hexagonally packed micelles and lamellar structures. Interesting findings demonstrated that regular features of flow curves, such as power-law shear thinning behavior, resulted from a wide variety of experimental artifacts that appeared when measuring microstructured fluids with shear rheometry.</p> <p> </p> <p>Finally, the successful integration of shear rheometry to calculate essential parameters to be used in a cost-effective visualization technique (still in development) used to calculate the dissolution time of polymers is addressed. The use of oscillatory rheometry successfully quantify the viscoelastic response of polyvinyl alcohol (PVA) solutions and identify formulations changes such as additive addition. The flow behavior of PVA solutions was correlated to dissolution behavior proving that the developed protocol has a high potential as a first screening tool.</p><br><p></p>
617

Shift

Arnold, Amanda Suzanne 03 August 2007 (has links)
The following is a collection of original poetry. The manuscript consists of an introduction explaining influences and style, and four chapters of poems categorized by subject matter: object/nature, writing/creativity, relationships, and family/figures. INDEX WORDS: Poetry, Poem
618

Macroscopic description of rarefied gas flows in the transition regime

Taheri Bonab, Peyman 01 September 2010 (has links)
The fast-paced growth in microelectromechanical systems (MEMS), microfluidic fabrication, porous media applications, biomedical assemblies, space propulsion, and vacuum technology demands accurate and practical transport equations for rarefied gas flows. It is well-known that in rarefied situations, due to strong deviations from the continuum regime, traditional fluid models such as Navier-Stokes-Fourier (NSF) fail. The shortcoming of continuum models is rooted in nonequilibrium behavior of gas particles in miniaturized and/or low-pressure devices, where the Knudsen number (Kn) is sufficiently large. Since kinetic solutions are computationally very expensive, there has been a great desire to develop macroscopic transport equations for dilute gas flows, and as a result, several sets of extended equations are proposed for gas flow in nonequilibrium states. However, applications of many of these extended equations are limited due to their instabilities and/or the absence of suitable boundary conditions. In this work, we concentrate on regularized 13-moment (R13) equations, which are a set of macroscopic transport equations for flows in the transition regime, i.e., Kn≤1. The R13 system provides a stable set of equations in Super-Burnett order, with a great potential to be a powerful CFD tool for rarefied flow simulations at moderate Knudsen numbers. The goal of this research is to implement the R13 equations for problems of practical interest in arbitrary geometries. This is done by transformation of the R13 equations and boundary conditions into general curvilinear coordinate systems. Next steps include adaptation of the transformed equations in order to solve some of the popular test cases, i.e., shear-driven, force-driven, and temperature-driven flows in both planar and curved flow passages. It is shown that inexpensive analytical solutions of the R13 equations for the considered problems are comparable to expensive numerical solutions of the Boltzmann equation. The new results present a wide range of linear and nonlinear rarefaction effects which alter the classical flow patterns both in the bulk and near boundary regions. Among these, multiple Knudsen boundary layers (mechanocaloric heat flows) and their influence on mass and energy transfer must be highlighted. Furthermore, the phenomenon of temperature dip and Knudsen paradox in Poiseuille flow; Onsager's reciprocity relation, two-way flow pattern, and thermomolecular pressure difference in simultaneous Poiseuille and transpiration flows are described theoretically. Through comparisons it is shown that for Knudsen numbers up to 0.5 the compact R13 solutions exhibit a good agreement with expensive solutions of the Boltzmann equation.
619

Studie odpočívky a velkokapacitního záchytného parkoviště pro TIR na dálnici D1 / The Study of the Parking Area on the Motorway D1

Šťastný, Radek January 2013 (has links)
The task of my diploma work is the study of the parking area on the motorway D1 near Vyškov. This place will be connected with the motorway D1 between the present exit Vyškov – West (226) and Vyškov – East (230/1) in the direction to Kroměříž. The parking area (the parking place, the petrol station, the restaurant) and the truckpark will be designed with the reason of the high intensity of cars and lorries on the motorway D1 and with the reason of the lack of the parking places for the lorries.
620

Supraleitung in Gallium-implantiertem Silizium / Superconductivity in gallium-implanted silicon

Skrotzki, Richard 21 July 2016 (has links) (PDF)
Die vorliegende Arbeit beschäftigt sich mit der elektrischen Charakterisierung 10 nm dünner Schichten bestehend aus amorphen Ga-Nanoclustern eingebettet in Ga-dotiertes polykristallines Si. Die Herstellung der Schichten geschieht via Ionen-Implantation in Si-Wafer samt anschließender thermischer Ausheilung. Elektrische Transportmessungen in Magnetfeldern von bis zu 50 T zeigen, dass die Schichten durch Variation der Ausheilparameter zwei strukturelle Supraleiter-Isolator-Übergänge durchlaufen. TEM-gestützte Strukturanalysen decken auf, dass den Übergängen eine Gefügetransformation zugrunde liegt, die das Wechselspiel zwischen supraleitender Cluster-Kopplung und kapazitiver Ladungsenergie sowie dem Ausmaß von thermischen und Quantenfluktuationen beeinflusst. Im supraleitenden Regime (Tc = 7 K) wird ein doppelt reentrantes Phänomen beobachtet, bei dem Magnetfelder von mehreren Tesla in anisotroper Form die Supraleitung begünstigen. Eine qualitative Erklärung gelingt via selbstentwickeltem theoretischen Modell basierend auf Phaseslip-Ereignissen für Josephson-Kontakt-Netzwerke. Für Anwendungen im Bereich der Sensor-Technologie und Quanten-Logik werden die Schichten erfolgreich via Fotolithographie und FIB (focused ion beam) mikro- und nanostrukturiert. Dadurch gelingt die erstmalige Beobachtung des Little-Parks-Effektes in einer Nanostruktur aus amorphem Ga. / The following thesis is devoted to the electrical characterization of 10 nm thin layers consisting of amorphous Ga nanoclusters embedded in Ga-doped polycrystalline Si. The preparation of the layers is realized via ion implantation in Si wafers plus subsequent thermal annealing. Electrical-transport measurements in magnetic fields of up to 50 T show that the layers undergo two structural superconductor-insulator transitions upon variation of the annealing parameters. Structural analyzes based on TEM investigations reveal an underlying transformation of the size and distance of the clusters. This influences the interplay of the superconducting cluster coupling and capacitive charging energy as well as the extent of thermal and quantum fluctuations. In the superconducting regime (Tc = 7 K) a double-reentrant phenomenon is observed. Here, magnetic fields of several Tesla facilitate superconductivity in an anisotropic way. A qualitative explanation is given via a self-developed theoretical model based on phase-slip events for Josephson-junction arrays. With respect to applications regarding sensor technology and quantum logic circuits the layers are successfully micro- and nanostructured via photolithography and FIB. This allows for the first observation of the Little-Parks effect in a nanostructure of amorphous Ga.

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