• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 464
  • 87
  • 74
  • 64
  • 48
  • 39
  • 16
  • 10
  • 8
  • 5
  • 4
  • 4
  • 3
  • 2
  • 2
  • Tagged with
  • 995
  • 130
  • 84
  • 79
  • 76
  • 71
  • 66
  • 65
  • 63
  • 62
  • 59
  • 58
  • 54
  • 51
  • 48
  • 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.
211

Matematikundervisning som kan stödja matematiskt begåvade elever

Håkansson, Marie, Lembrér, Dorota January 2009 (has links)
Målet med detta arbete är att undersöka hur elever med begåvning i matematik undervisas. Uppsatsen redovisar en studie där två rektorer och fem pedagoger intervjuats utifrån frågorna: Vilka resurser och vilket stöd ges matematiskt begåvade elever? Hur undervisas och upptäcks de? Vilket stöd har lärarna i arbetet med dessa elever? Redovisningen av undersökningens resultat visar att majoriteten av pedagogerna saknar kunskap, resurser och stöd för att undervisa matematiskt begåvade elever. Uppfattningen att undervisningen för matematiskt begåvade elever bör differentieras på olika sätt, ges stöd för i forskning. Dels bör den hastighetsanpassas, dels bör den innehålla berikande uppgifter. Det konstateras även att svensk grundskola saknar strategier för att upptäcka och undervisa dessa elever. / The purpose of this essay is to describe the tuition of pupils gifted in mathematics. A survey was performed; two headmasters and five pedagogues were interviewed with the following questions: What resources and what support are given to mathematically gifted pupils? How are these pupils tutored and discerned? What support have the teachers got in their teaching of these pupils? The result of the survey shows that the majority of the pedagogues lack knowledge, resources and support to tutor mathematically gifted pupils. According to research the tuition of mathematically gifted pupils should be differentiated. It should, partly, be pace adapted, partly, contain enriching tasks. It is also concluded that the Swedish elementary school lack strategies to discern and tutor these pupils.
212

Academic Acceleration In Florida Elementary Schools: A Survey Of Attitudes, Policies, And Practices

Guilbault, Keri 01 January 2009 (has links)
The focus of this research was to provide recent descriptive information about acceleration policies and practices in Florida elementary schools. District, school, and personal demographic variables were investigated to determine the extent to which they affected school-based acceleration options provided for students. Also, school district policies were examined to determine which types of research-based acceleration options were more frequently used and what procedures were in place to guide the decision-making process. Results from this study indicated that extant acceleration policies only included grade skipping and limited procedures for referral, screening and decision-making in the schools. The most common types of acceleration offered in Florida elementary schools were subject acceleration in the Language Arts and Mathematics provided outside of the regular classroom, continuous progress, and curriculum compacting. The most frequently selected reason for not accelerating a student listed by both school principals and district administrators of gifted education programs was concern over a student's social and emotional development. No relationship was found to exist between schools' or principals' personal demographic variables and types of acceleration offered in elementary schools. No relationship was found between elementary school principals' knowledge of gifted learners and the types of acceleration implemented in their schools.
213

Acceleration of Jaccard's Index Algorithm for Training to Tag Damage on Post-earthquake Images

Mulligan, Kyle John 01 June 2018 (has links) (PDF)
There are currently different efforts to use Supervised Neural Networks (NN) to automatically label damages on images of above ground infrastructure (buildings made of concrete) taken after an earthquake. The goal of the supervised NN is to classify raw input data according to the patterns learned from an input training set. This input training data set is usually supplied by experts in the field, and in the case of this project, structural engineers carefully and mostly manually label these images for different types of damage. The level of expertise of the professionals labeling the training set varies widely, and some data sets contain pictures that different people have labeled in different ways when in reality the label should have been the same. Therefore, we need to get several experts to evaluate the same data set; the bigger the ground truth/training set the more accurate the NN classifier will be. To evaluate these variations among experts, which can be considered equal to the task of evaluating the quality of the expert, using probabilistic theory we first need to implement a tool able to compare different images classified by different experts and apply a certainty level to the experts tagged labels. This master's thesis implements this comparative tool. We also decided to implement the comparative tool using parallel programming paradigms since we foresee that it will be used to train multiple young engineering students/professionals or even novice citizen volunteers (“trainees”) during after-earthquake meetings and workshops. The implementation of this software tool involves selecting around 200 photographs tagged by an expert with proven accuracy (“ground truth”) and comparing them to files tagged by the trainees. The trainees are then provided with instantaneous feedback on the accuracy of their damage assessment. The aforementioned problem of evaluating trainee results against the expert is not as simple as comparing and finding differences between two sets of image files. We anticipate challenges in that each trainee will select a slightly different sized area for the same occurrence of damage, and some damage-structure pairs are more difficult to recognize and tag. Results show that we can compare 500 files in 1.5 seconds which is an improvement of 2x faster compared to sequential implementation.
214

Shaking and Balance of a Convertible One- and Two-Cylinder Reciprocating Compressor

Ong, Chin Guan 10 March 2000 (has links)
This research involves the study of a one- and two-cylinder convertible reciprocating Freon compressor for air conditioning or refrigeration purposes. The main concern is the reduction of the vibration (noise) caused during the operation of the compressor. Vibration is a main concern when the compressor is shifted from the one-cylinder operation to the two-cylinder operation mode and the reverse of this shift. The objectives for this research are (1) to investigate the shaking force due to the reciprocating mass at high frequencies, which are up to 4600 Hz (80w) in this research; (2) to determine the dominant force for compressor vibration among the three possible sources of shaking force due to reciprocating mass, impact forces due to clearance at the connecting rod - piston joint, and the z-axis force from the motor torque due to the rotor's conductor rods being skewed at an angle; (3) to minimize the difference in change of kinetic energies when switching between the one- and two-cylinder operating modes of the compressor. The properties of the vibration in one- and two-cylinder operation have been studied and results have been analyzed in terms of kinetic energies generated in different setting of operation of the compressor. Dynamic simulation for the impact force is computed using SIMULINK. The Z-axis force due to the motor is computed. Results indicated that shaking force due to the reciprocating mass is the dominant force for only the first two harmonics (w, 2w). An optimization routine based on Hooke and Jeeves pattern search method is developed and an optimized setting of angle, force, and torque for balancing of the crankshaft to achieve objective (3) is determined. / Master of Science
215

Support for Accessible Bitsliced Software

Conroy, Thomas Joseph 05 March 2021 (has links)
The expectations on embedded systems have grown incredibly in recent years. Not only are there more applications for them than ever, the applications are increasingly complex, and their security is essential. To meet such demanding goals, designers and programmers are always looking for more efficient methods of computation. One technique that has gained attention over the past couple of decades is bitsliced software. In addition to high efficiency in certain situations, including block ciphers computation, it has been used in designs to resist hardware attacks. However, this technique requires both program and data to be in a specific format. This requirement makes writing bitsliced software by hand laborious and adds computational overhead to transpose the data before and after computation. This work describes a code generation tool that produces it from a higher-level description in Verilog. By supporting the synthesis of sequential circuits, this tool extends bitsliced software to parallel synchronous software. This tool is then used to implement a method for accelerating software neural network processing with reduced-precision computation on highly constrained devices. To address the data transposition overhead and to support a hardware attack-resistant architecture, a custom DMA controller is introduced that efficiently transposes the data as it transfers along with dedicated hardware for masking and redundancy generation. In combination, these tools make bitsliced software and its benefits more accessible to system designers and programmers. / Master of Science / Small computers embedded in devices, such as cars, smart devices, and other electronics, face many challenges. Often, they are pushed to their limits by designers and programmers to reach acceptable levels of performance. The increasing complexity of the applications they run compounds with the need for these applications to be secure. The programmers are always looking for better, more efficient methods of doing computations. Over the past two decades bitsliced software has gained attention as a technique that can, in certain situations, be more efficient than standard software. It also has properties that make it useful for designs implementing secure software. However, writing bitsliced software by hand is a laborious task, and the data input to the software needs to be in a specific format. To make writing the software easier, a tool that generates it from the well-known Verilog hardware description language is discussed in this work. This tool is then used to implement a method to accelerate artificial intelligence calculations on highly constrained computers. A custom hardware module is also introduced to speed up the formatting of data for bitsliced processing. In combination, these tools make bitsliced software and its benefits more accessible.
216

Real-time Rendering of Burning Objects in Video Games

Amarasinghe, Dhanyu Eshaka 08 1900 (has links)
In recent years there has been growing interest in limitless realism in computer graphics applications. Among those, my foremost concentration falls into the complex physical simulations and modeling with diverse applications for the gaming industry. Different simulations have been virtually successful by replicating the details of physical process. As a result, some were strong enough to lure the user into believable virtual worlds that could destroy any sense of attendance. In this research, I focus on fire simulations and its deformation process towards various virtual objects. In most game engines model loading takes place at the beginning of the game or when the game is transitioning between levels. Game models are stored in large data structures. Since changing or adjusting a large data structure while the game is proceeding may adversely affect the performance of the game. Therefore, developers may choose to avoid procedural simulations to save resources and avoid interruptions on performance. I introduce a process to implement a real-time model deformation while maintaining performance. It is a challenging task to achieve high quality simulation while utilizing minimum resources to represent multiple events in timely manner. Especially in video games, this overwhelming criterion would be robust enough to sustain the engaging player's willing suspension of disbelief. I have implemented and tested my method on a relatively modest GPU using CUDA. My experiments conclude this method gives a believable visual effect while using small fraction of CPU and GPU resources.
217

Wireless MEMS Accelerometer for Real-Time Small Laboratory Animal Activity Monitoring

Lu, Cheng-Kuan January 2008 (has links)
No description available.
218

The Effect of Variable Gravity on the Cooling Performance of a Partially-Confined FC-72 Spray

Michalak, Travis Edward 29 June 2009 (has links)
No description available.
219

Design, simulation, and modeling of MEMS angular acceleration inertial switch with tunable threshold

Alahmdi, Raed L. 07 1900 (has links)
We present the design and analysis of a new type of MEMS inertia switch with a tunable threshold, which can passively sense angular acceleration. The designs have a big proof mass for inducing rotation due to the angular impacts and also flexible cantilever beams to tune the acceleration threshold. The proposed designs were simulated using COMSOL Multiphysics, analytically modeled, and numerically integrated using MATLAB. The results showed that the acceleration can be tuned from 0 rad/s$^2$ to 65,000 rad/s$^2$ based on the used electrostatic voltage. The designs experience less than 10% overshot for shock durations higher than 20 ms. The rise time was less than 10 ms for all designs when the applied shock duration was less than 30 ms. The designs’ tunabilities were studied and characteristic angular acceleration versus tuning voltage graphs were developed for each design. The tuning voltage varied between the designs where the maximum pull-in voltage was 179 V in Design 2 and the minimum pull-in voltage was 59 V in Design 4.
220

A Search for Axion-like Particles at the Coherent CAPTAIN Mills Experiment

Dunton, Edward C. January 2022 (has links)
While the standard model is enormously successful and internally self consistent, it does not explain a great number of phenomena and is far from a complete theory of particle interactions. Among these missing pieces are a particle theory of dark matter and the Strong CP problem in Quantum Chromodynamics (QCD). A hypothetical axion-like particle (ALP) is a prospective solution to both problems and can be searched for at accelerator produced beam dump experiments. Neutrino detectors can be used for such a search, due to the similar energy regimes and interactions channels of such detections. The Coherent CAPTAIN Mills (CCM) experiment at the Los Alamos Neutron Science Center (LANCSE) has carried out a search for these ALPs across a number of theoretical models, including dark sector variants and the light QCD axion. An initial run with 120 photomultiplier tubes (PMTs) was used to identify 95\% confidence limits placed across parameter space using an engineering run, which identified several paths to improvement for a longer term search to probe the majority of theoretically motivated parameter space.

Page generated in 0.0463 seconds