Physical Sciences and Mathematics Commons^™

An Analysis Of Constructive Network Formation Models, Gary Fredericks

Theses and Dissertations

We study a family of network formation models to determine how payment rules affect the final network topologies that emerge. In our model a set of nodes starts out without any edges and the nodes must pay for the creation of edges using one of several different payment mechanisms. Example payment mechanisms include one node paying for the whole edge, and the cost being shared equally between the two nodes. We show how the set of networks formed by some payment rules are subsets of those formed by other rules. We also perform extensive empirical tests on networks of up …

Walkcompass: Finding Walking Direction Leveraging Smartphone's Inertial Sensors, Nirupam Roy

Theses and Dissertations

Determining moving direction with smartphone's inertial sensors is a well known problem in the field of location service. Compass alone cannot solve this problem because smartphone's compass cannot achieve high accuracy. Moreover GPS is not suitable in indoor scenario. Another well known approach is dead-reckoning but dead-reckoning needs to know phones initial orientation and over time it keeps accumulating errors and after some time the estimation becomes to noisy to use. To overcome these limitations, we propose a solution called WalkCompass which is specially designed for pedestrians keeping in mind the variation of force during normal human walk. Therefore the …

3d Grain Segmentation In Superalloy Images Using Multichannel Edge-Weighted Centroidal Voronoi Tessellation Based Methods, Yu Cao

Theses and Dissertations

Accurate grain segmentation on 3D superalloy images is very important in materials science and engineering. From grain segmentation, we can derive the underlying superalloy grains' micro-structures, based on which many important physical, mechanical and chemical properties of the superalloy samples can be evaluated. However, grain segmentation is usually a very challenging problem since: 1) even a small 3D superalloy sample may contain hundreds of grains; 2) carbides and noises may degrade the imaging quality; and 3) the intensity within a grain may not be homogeneous. In addition, the same grain may present different appearances, i.e. intensities, under different microscope settings. …

Accelerating Short Read Mapping Using A Dsp Based Coprocessor, Shaun I. Gause

Theses and Dissertations

Advances in next generation sequencing technologies have allowed short reads to be generated at an increasing rate, shifting the bottleneck of the sequencing process to the short read mapping computations. High costs and extended processing times drive researchers to pursue more efficient solutions with an overall goal of a short read mapping architecture capable of processing short reads as they are generated. Digital signal processors have shown high performance capabilities while maintaining low power consumption in a wide field of applications. This thesis explores the use of a DSP accelerated exact match short read mapping algorithm, focusing on a performance …

Plc Code Vulnerabilities Through Scada Systems, Sidney E. Valentine, Jr.

Theses and Dissertations

Supervisory Control and Data Acquisition (SCADA) systems are widely used in automated manufacturing and in all areas of our nation's infrastructure. Applications range from chemical processes and water treatment facilities to oil and gas production and electric power generation and distribution. Current research on SCADA system security focuses on the primary SCADA components and targets network centric attacks. Security risks via attacks against the peripheral devices such as the Programmable Logic Controllers (PLCs) have not been sufficiently addressed.

Our research results address the need to develop PLC applications that are correct, safe and secure. This research provides an analysis of …

Accelprint:Accelerometers Are Different By Birth, Sanorita Dey

Theses and Dissertations

This paper submits a hypothesis that smartphone accelerometers possess unique fingerprints. We believe that the fingerprints arise from hardware imperfections during the sensor manufacturing process, causing every sensor chip to respond differently to the same motion stimulus. The differences in responses are subtle enough that they do not affect most of the higher level functions computed on them. Nonetheless, upon close inspection, these fingerprints emerge with consistency, and can even be somewhat independent of the stimulus that generates them. Measurements and classification on 80 standalone accelerometer chips, 25 Android phones, and 2 tablets, show precision and recall upward of 96%, …

Multi-Label Segmentation Propagation For Materials Science Images Incorporating Topology And Interactivity, Jarrell Waggoner

Theses and Dissertations

Segmentation propagation is the problem of transferring the segmentation of an image to a neighboring image in a sequence. This problem is of particular importance to materials science, where the accurate segmentation of a series of 2D serial-sectioned images of multiple, contiguous 3D structures has important applications. Such structures may have prior-known shape, appearance, and/or topology among the underlying structures which can be considered to improve segmentation accuracy. For example, some materials images may have structures with a specific shape or appearance in each serial section slice, which only changes minimally from slice to slice; and some materials may exhibit …