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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.
101

Guidance in articulation of the elementary and secondary schools

Unknown Date (has links)
"During the last few years many changes have been made in the educational program. These changes have come about through experimentation and study on the part of children and youth, as well as principals, supervisors, teachers, parents, and the members of the entire community"--Introduction. / "August, 1950." / Typescript. / Advisor: H. W. Dean, Professor Directing Paper. / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the Degree of Master of Education under Plan II." / Includes bibliographical references (leaves 47-48).
102

Drag Coefficients for Magnetically Accelerated Spheres

Liang, Jann-Wuu 01 August 1966 (has links)
The objective of this study was to determine the correlation of the drag coefficient of an accelerating sphere in the liquid medium over a range of Reynolds number from 0.1 to 100, 000. A magnetic accelerator was used to obtain an acceleration for the sphere, the data was recorded using a photograph and a digital computer was used to reduce the data.
103

An Experimental Investigation of the Effect of a Constant Body Force Field Upon the Drag Coefficient of a Sphere

Boyack, Brent Evans 30 May 1964 (has links)
The object of this thesis was to present the method and results of an experimental determination and correlation of the drag coefficients of accelerating spheres.
104

FPGA Acceleration of Decision-Based Problems using Heterogeneous Computing

Thong, Jason January 2014 (has links)
The Boolean satisfiability (SAT) problem is central to many applications involving the verification and optimization of digital systems. These combinatorial problems are typically solved by using a decision-based approach, however the lengthy compute time of SAT can make it prohibitively impractical for some applications. We discuss how the underlying physical characteristics of various technologies affect the practicality of SAT solvers. Power dissipation and other physical limitations are increasingly restricting the improvement in performance of conventional software on CPUs. We use heterogeneous computing to maximize the strengths of different underlying technologies as well as different computing architectures. In this thesis, we present a custom hardware architecture for accelerating the common computation within a SAT solver. Algorithms and data structures must be fundamentally redesigned in order to maximize the strengths of customized computing. Generalizable optimizations are proposed to maximize the throughput, minimize communication latencies, and aggressively compact the memory. We tightly integrate as well as jointly optimize the hardware accelerator and the software host. Our fully implemented system is significantly faster than pure software on real-life SAT problems. Due to our insights and optimizations, we are able to benchmark SAT in uncharted territory. / Thesis / Doctor of Philosophy (PhD)
105

Fatigue acceleration of crack growth in medium density polyethylene

Ezzat, Showaib A. January 1993 (has links)
No description available.
106

ACCELERATED CONSTRUCTION DECISION MAKING PROCESS

ARURKAR, TEJAS PRAKASH 02 October 2006 (has links)
No description available.
107

Particle Acceleration Asymmetry in a Reconnecting Nonneutral Current Sheet.

Zharkova, Valentina V., Gordovskyy, Mykola 26 October 2009 (has links)
No / The acceleration of electrons and protons caused by a super-Dreicer electric field directed along the longitudinal component By of the magnetic field is investigated. The three-component magnetic field in a nonneutral current sheet occurring at the top of the reconnecting flaring loops on the charged particle trajectories and energies is considered. Particle trajectories in the reconnecting current sheet (RCS) and their energy spectra at the point of ejection from the RCS are simulated from the motion equation for different sheet thicknesses. A super-Dreicer electric field of the current sheet is found to accelerate particles to coherent energy spectra in a range of 10-100 keV for electrons and 100-400 keV for protons with energy slightly increasing with the sheet thickness. A longitudinal By component was found to define the gyration directions of particles with opposite charges toward the RCS midplane, i.e., the trajectory symmetry. For the ratio By/Bz < 10-6 the trajectories are fully symmetric, which results in particle ejection from an RCS as neutral beams. For the ratio By/Bz > 10-2 the trajectories completely lose their symmetry toward the RCS midplane, leading to the separation of particles with opposite charges into the opposite halves from an RCS midplane and the following ejection into different legs of the reconnecting loops. For the intermediate values of By/Bz the trajectories are partially symmetric toward the midplane, leading to electrons prevailing in one leg and protons in the other.
108

A Computational Study into the Effect of Structure and Orientation of the Red Ear Slider Turtle Utricle on Hair Bundle Stimulus

Davis, Julian Ly 28 December 2007 (has links)
The vestibular system consists of several organs that contribute to ones sense of balance. One set of organs, otoconial organs, have been shown to respond to linear acceleration (1949). Hair bundles (and hair cells), which are the mechano-electric transducers found within otoconial organs, respond to displacement of the overlying otoconial membrane (OM). Structure, position and orientation of the OM within the head may influence the stimulus of hair bundles by changing the deformation characteristics of the OM. Therefore, studying the deformation characteristics of the OM with finite element models presents a unique advantage: the ability to study how different variables may influence the deformation of the OM. Previous OM models have ignored complicated OM geometry in favor of single degree of freedom (De Vries 1951)or distributed parameter models (Grant et al. 1984; Grant and Cotton 1990; Grant et al. 1994). Additionally, OMs have been modeled considering three dimensional geometry (Benser et al. 1993; Kondrachuk 2000; 2001a), however OM layer thicknesses were assumed to be constant. Further, little research has investigated the effect of position and orientation of otoconial organs on the deformation of the OM (Curthoys et al. 1999), due to natural movement of the head. The effect of structure, position and orientation of the utricle of a red ear slider turtle on the stimulation of hair bundles in the OM is investigated here. Using confocal images, a finite element model of the utricle OM is constructed considering its full 3D geometry and varying OM layer thickness. How specific geometric variables, which are missing from other OM models, effect the deformation of the utricle OM is studied. Next, since hair bundles are part of the structure of the OM, their contribution to the deformation of the utricular OM is quantified. Then, using computed tomography of a turtle head and high speed video of turtle feeding strikes, acceleration at the utricle during natural motion is estimated. Finally, the effects of orientation of the utricle in the head on the stimulus of hair bundles within the organ is investigated. In summary, a model and methods are developed through which deformation of the turtle utricle OM through natural movements of the head may be studied. Variables that may contribute to utricle OM deformation are investigated. Utricle OM geometry, hair bundles, position and orientation all play a role in utricle OM deflection and therefore hair bundle stimulus. Their effects are quantified and their roles are discussed in this dissertation. / Ph. D.
109

Vehicle Dynamics Model for Predicting Maximum and Typical Acceleration Rates for Passenger Vehicles

Snare, Matthew C. 27 August 2002 (has links)
Effectively modeling the acceleration behavior of vehicles is an important consideration in a variety of transportation engineering applications. The acceleration profiles of vehicles are important in the geometric design of roadways and are used to model vehicle behavior in simulation software packages. The acceleration profile of the vehicle is also a critical parameter in fuel consumption and emissions models. This paper develops and validates a vehicle dynamics model to predict the maximum acceleration rates of passenger vehicles. The model is shown to be superior to other similar models in that it accurately predicts speed and acceleration profiles in all domains and for a variety of vehicle types. The paper also modifies the model by introducing a reduction factor, which enables the model to predict the typical acceleration patterns for different driver types. The reduction factors for the driving population are shown to follow a normal distribution with a mean of 0.60 and a standard deviation of 0.08. The paper also provides new data sets containing maximum and typical acceleration profiles for thirteen different vehicles and twenty different drivers. / Master of Science
110

An Analysis of Catcher's Mask Performance to Attenuate Head Accelerations

Shain, Kellen Saul 07 May 2010 (has links)
The goals of this study were to measure the ability of catcher's masks to attenuate head accelerations upon impact with a baseball, and to compare these head accelerations to established injury thresholds for concussions. Testing involved using a pneumatic cannon to shoot baseballs at an instrumented (3-2-2-2 accelerometer array) Hybrid III headform (a 50th percentile male head and neck) with and without a catcher's mask on the head. The ball speed was controlled from approximately 26.8 – 35.8 m/s (60 – 80 mph) and regulation NCAA baseballs were used. Peak linear resultant acceleration was 140 – 180 g without a mask and 16 – 30 g with a mask over the range of balls speeds investigated. Peak angular resultant acceleration was 19500 – 25700 rad/sec2 without a mask and 2250 – 3230 rad/sec2 with a mask. The Head Injury Criterion was 93 – 181 without a mask and 3 – 13 with a mask and the Severity index was 110 – 210 without a mask and 3 – 15 with a mask. Catcher's masks reduced head acceleration metrics by approximately 85% when baseballs were impacted with just the headform. Head accelerations with a catcher's mask were substantially lower than contemporary injury thresholds, yet evidence indicates that baseball impacts to the mask still result in concussions. / Master of Science

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