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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.
61

The Success of Failure Temporal Interpretation and the Glitch Process

Birdsong, Todd Todd 01 August 2015 (has links)
The past is a statement; the future a question. Henri Cartier-Bresson provides us with an interpretation of the “now” with the decisive moment and it is through this lens that I examine the glitch. Like the street photography style that Cartier-Bresson pioneered, the glitch artist role is not to simply create, but lies in inviting and reacting to conditions that will permit art to happen. Similar to the camera’s shutter being triggered, the glitch is initialized in a moment of uncertainty by our analog selves and is revealed to be dissident code that is set free from the pristine constructs of the digital format. As the glitch is an affective event that happens in real time, or in a moment, it can be recorded, captured and documented as a breakthrough of noise separated from the signal. As a culture, we tend to filter out and defend against the noise of the glitch while keeping the myth of perfect signal alive. I would suggest that we welcome the noise as a type of natural wilderness in the machine that reveals the illusion of the digital era and blurs the lines between transcription and transcoding.
62

Využití aktuálního točivého momentu ze sběrnice Can-Bus pro stanovení aktuálního výkonu motoru

Hanuš, Pavel January 2011 (has links)
No description available.
63

Vliv změny předstihu zážehu a směšovacího poměru na výkonové parametry spalovacího motoru

Staněk, Jan January 2011 (has links)
No description available.
64

Living Pedagogical Moments Between Curriculum as Lived and Curriculum as Plan: A Phenomenological Inquiry Into the Tensions of Teacher Education

Knowles, Kelsey January 2015 (has links)
This master’s research is a phenomenological inquiry into the pedagogical moment in teacher education. This phenomenon is explored through a conceptual lens that draws from the phenomenological pedagogical ideals that are intrinsic to the work of both Ted Aoki and Max van Manen. Following a comprehensive outline of the phenomenological methodology that guides this thesis, the pedagogical moment is described in terms of three phases: tension, opening and pulse. The phenomenon is further explored through several sub themes relating to the lifeworld existentials (time, body, space, relation to other). This research intertwines several phenomenological concepts (such as intentionality, embodiment, consciousness, pedagogy, and motion sensitive phenomenology), within the context of one “living” phenomenon as a way of shedding light on what it is like to experience a pedagogical moment from within the tensions of practicum teaching.
65

Moment-rotation behaviour of universal beam to tubular column connections using reverse channel

Li, Xue January 2012 (has links)
Steel tubular structures are becoming more widely used in recent years because of their excellent structural performance as well as appearance. For structures with steel hollow section (SHS) columns and concrete filled tubular (CFT) columns, several types of joint may be used to connect to wide flange beams. The topic of this research is a relatively new type of joint, the 'reverse channel' connection, in which the legs of a channel are welded to the tube thus converting the closed tubular column into an open section for connection purpose. However, since tubular columns have only recently become more popular in frames, there is a lack of research to quantify the moment-rotation characteristics of connections between I beams and tubular columns. A total of eight tests on loaded steel beam to RHS column connections using reverse channel and endplate, up to collapse, were carried out. The objectives of these tests were to investigate the effects of different connection details on connection performance and to provide experimental data for validation of numerical simulations. Validation of numerical modelling was carried out to check accuracy of the numerical simulation model developed using the general finite element package ABAQUS. The validated ABAQUS model was then used to perform various parametric studies to provide insight into structural behaviour. A systematic approach to quantify the load carrying capacity of the reverse channel web and the column face were adopted based on yield line theory. This thesis presents the derivation and validation of the analytical approach. The moment resistance of the whole connection can be obtained by assembling all the components together. A procedure for calculation was proposed to provide feasibility for designer and the analytical results were compared with the test results.
66

Kinematická a kinetická analýza skoků ve sportovní gymnastice / Kinematic and kinetic analysis of artistic gymnastic jumps

Benetková, Hana January 2016 (has links)
Title: Kinematic and kinetic analysis of artistic gymnastic jumps Objectives: The aim of my master thesis is execution of kinematic - kinetic analysis of jumps in artistic gymnastics, processing data, counting force moment, which does the rotation around ventrodorsal axis, means abduction and adduction motion and recount normalized moment (moment share by body weight). Methods: The kinematic - kinetic analysis of jumps in artistic gymnastics was done by using systems Qualysis Motion Capture System and Kistler. Results: We have been researching four different gymnastic jumps in this study. Four healthy individuals underwent the measurement. They have done each jump in free valid times. There was measured abduction moment of knee joint in each jump. Adduction moments were present only in 32 % cases and lot of them hasn't significant value. There was measured abduction moment in bounces in each jump, value of standardized adduction moment wasn't signifiant. There was measured just abduction moments in dismounts of non-rotational jumps. In dismounts of rotational jumps (around longitudinal axes) was measured abduction and also adduction moment. Values of normalized abduction moments were between 0,3 - 11 m2 .s-2 . Values of normalized adduction moments were between 0 - 10 m2 .s-2 . Highest values of...
67

First-Order Hyperbolic-Relaxation Turbulence Modelling for Moment-Closures

Yan, Chao 15 June 2022 (has links)
This dissertation presents a study of hyperbolic turbulence modelling for the Gaussian ten-moment equations. In gaskinetic theory, moment closures offer the possibility of deriving a series of gas-dynamic governing equations from the Boltzmann equation. One typical example, the Gaussian ten-moment model, which takes the form of hyperbolic-relaxation equations, is considered as a competitive model for viscous gas flow when heat transfer effects are negligible. The hyperbolic nature of this model gives it several numerical advantages, compared to the Navier-Stokes equations. However, until this study, the application of the ten-moment equations has been limited to laminar flows, due to the lack of appropriate turbulence models. In this work, the ten-moment equations are, for the first time, Reynolds-averaged. The resulting equations inherit the hyperbolic balance-law form from the original equations with new unknowns, which require approximation by turbulence models. Most of the traditional turbulence models for the Reynolds-averaged Navier-Stokes equations are not perfectly well-suited for the Reynolds-averaged ten-moment equations, because the second-order derivatives presented in these models can break the pure hyperbolic nature of the original model. The relaxation methods are therefore proposed in this project to reform the existing turbulence models. Two relaxation methods, the Chen-Levermore-Liu p-system and Cattaneo-Vernotte models, are used to hyperbolize the Prandtl’s one-equation model, standard k-ε model and Wilcox k-ω model. The hyperbolic versions of these turbulence models are first shown to be equivalent to their original forms. They are then coupled to the Reynolds-averaged ten-moment equations to build the overall hyperbolic governing equations for turbulence flows. An axisymmetric version of Reynolds-averaged ten-moment equations is also derived. A dispersion analysis is conducted for the resulting governing equations, which shows the corresponding dispersive behaviour and stability. The effect of the relaxation parameters is investigated through several numerical tests. All derived turbulence models are applied to solve canonical validation test problems, including two-dimensional planar mixing-layer, free-jet and circular free-jet. The numerical evaluations are analysed and compared against existing experimental measurements.
68

Ductile Design and Predicted Inelastic Response of Steel Moment Frame Buildings for Extreme Wind Loads

Giles, Tyler Eric 29 July 2021 (has links)
Inelastic design methods have been used in seismic design for several years and are well accepted in engineering practice. In contrast, an inelastic wind design method is yet to be developed, in part due to the inherent differences between seismic forces and wind forces. Current wind design practice follows a linear method to find a design windspeed for the location where the structure will be built. Once the design windspeed has been determined, the lateral force resisting system is designed such that it will behave elastically. This study was conducted with the hypothesis that by providing ductility at the material level, member level, and system level it may be possible to use a reduced design force for wind (i.e., a design force reduction that is proportional to a wind response modification factor). A three-story office building that uses steel moment frames as the primary lateral force resisting system was examined to test the hypothesis. Various levels of ductility were included based on ductility requirements for material strength, section stability and system stability originally developed for seismic design. Moment frames were designed for a range of design windspeeds and for three levels of ductility. For each design windspeed, a non-ductile (representing the moment frame as it would be designed by current standards), moderately-ductile and highly-ductile moment frame were developed. A finite element model of the building was made to capture inelastic material behavior and large displacements. The finite element model was subjected to wind loads based on wind tunnel tests data, and the static pushover, vibration, and dynamic responses of the building were evaluated. The performance of each moderately-ductile and highly-ductile moment frame was compared to the performance of each non-ductile frame of a higher design windspeed. The results show that for moderately-ductile moment frames, a wind response modification factor equal to 2 provided a collapse capacity that met or exceeded the collapse capacity of the comparative nonductile moment frame. For highly-ductile moment frames, a wind response modification factor equal to 3 met or exceeded the collapse capacity of the comparative non-ductile moment frame. In many instances, the collapse capacity of the moderately-ductile moment frame was similar to the collapse capacity of the highly-ductile moment frame. Thus, the results indicate that the use of a response modification factor for wind may be viable.
69

Relativistic Energy Correction Of The Hydrogen Atom With An Anomalous Magnetic Moment

Ambogo, David Otieno 17 July 2015 (has links)
The electron is known to possess an anomalous magnetic moment, which interacts with the gradient of the electric field. This makes it necessary to compute its effects on the energy spectrum. Even though the Coulomb Dirac equation can be solved in closed form, this is no longer possible when the anomalous magnetic moment is included. In fact the interaction due to this term is so strong that it changes the domain of the Hamiltonian. From a differential equation point of view, the anomalous magnetic moment term is strongly singular near the origin. As usual, one has to resort to perturbation theory. This, however, only makes sense if the eigenvalues are stable. To prove stability is therefore a challenge one has to face before actually computing the energy shifts. The first stability results in this line were shown by Behncke for angular momenta κ ≥ 3, because the eigenfunctions of the unperturbed Hamiltonian decay fast enough near the origin. He achieved this by decoupling the system and then using the techniques available for second order differential equations. Later, Kalf and Schmidt extended Behncke’s results basing their analysis on the Prüfer angle technique and a comparison result for first order differential equations. The Prüfer angle method is particularly useful because it shows a better stability and because it obeys a first order differential equation. Nonetheless, Kalf and Schmidt had to exclude some coupling constants for κ > 0. This I believe is an artefact of their method. In this study, I make increasing use of asymptotic integration, a method which is rather well adapted to perturbation theory and is known to give stability results to any level of accuracy. Together with the Prüfer angle technique, this lead to a more general stability result and even allows for an energy shifts estimate. Hamiltonians traditionally treated in physics to describe the spin-orbit effect are not self adjoint i.e. they are not proper observables in quantum mechanics. Nonetheless, naive perturbation theory gives correct results regarding the spectrum. To solve this mystery, one has to study the nonrelativistic limit of the Dirac operator. In the second part of this study, I have not only given the higher order correction to the Dirac operator but also shown the effects of the spin-orbit term.
70

Vliv předstihu zážehu na konečné složení spalin

Benáček, Richard January 2017 (has links)
The thesis deals with issues of the internal combustion engines, particularly the influence of ignition time on the parameters of petrol engine. The aim of this study was to determine the influence of the nature of the combustion products on the ignition time. The measurement took place at the Brno engine testing room of ABC Company, a private venture developing turbo-chargers. The measured values were then processed following a beforehand established methodology. The results presented in the following show the influence of ignition time on the production of combustion products and power parameters of petrol engine. This way the results allow optimization according to operational requirements.

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