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240 full-text articles. Page 11 of 11.

Sensorchestra: Collaborative Sensing For Symbolic Location Recognition, Heng-Tze Cheng, Feng-Tso Sun, Senaka Buthpitiya, Martin L. Griss 2011 Carnegie Mellon University

Sensorchestra: Collaborative Sensing For Symbolic Location Recognition, Heng-Tze Cheng, Feng-Tso Sun, Senaka Buthpitiya, Martin L. Griss

Martin L Griss

"Symbolic location of a user, like a store name in a mall, is essential for context-based mobile advertising. Existing fingerprint- based localization using only a single phone is susceptible to noise, and has a major limitation in that the phone has to be held in the hand at all times. In this paper, we present SensOrchestra, a col- laborative sensing framework for symbolic location recognition that groups nearby phones to recognize ambient sounds and images of a location collaboratively. We investigated audio and image features, and designed a classifier fusion model to integrate estimates from diff erent phones. We also …


Activity-Aware Mental Stress Detection Using Physiological Sensors, Feng-Tso Sun, Cynthia Kuo, Heng-Tze Cheng, Senaka Buthpitiya, Patricia Collins, Martin Griss 2011 Carnegie Mellon University

Activity-Aware Mental Stress Detection Using Physiological Sensors, Feng-Tso Sun, Cynthia Kuo, Heng-Tze Cheng, Senaka Buthpitiya, Patricia Collins, Martin Griss

Martin L Griss

"Continuous stress monitoring may help users better understand their stress patterns and provide physicians with more reliable data for interventions. Previously, studies on mental stress detection were limited to a laboratory environment where participants generally rested in a sedentary position. However, it is impractical to exclude the effects of physical activity while developing a pervasive stress monitoring application for everyday use. The physiological responses caused by mental stress can be masked by variations due to physical activity. We present an activity-aware mental stress detection scheme. Electrocardiogram (ECG), galvanic skin response (GSR), and accelerometer data were gathered from 20 participants across …


Omnisense: A Collaborative Sensing Framework For User Context Recognition Using Mobile Phones, Heng-Tze Cheng, Senaka Buthpitiya, Feng-Tso Sun, Martin L. Griss 2011 Carnegie Mellon University

Omnisense: A Collaborative Sensing Framework For User Context Recognition Using Mobile Phones, Heng-Tze Cheng, Senaka Buthpitiya, Feng-Tso Sun, Martin L. Griss

Martin L Griss

Context information, including a user’s locations and activities, is indispensable for context-aware applications such as targeted advertising and disaster response. Inferring user context from sensor data is intrinsically challenging due to the semantic gap between low-level signals and high-level human activities. When implemented on mobile phones, more challenges on resource limitations are present. While most existing work focuses on context recognition using a single mobile phone, collaboration among multiple phones has received little attention, and the recognition accuracy is susceptible to phone position and ambient changes. Simply putting a phone in one’s pocket can render the microphone muffled and the …


Room-Level Wi-Fi Location Tracking, Joshua Correa, Ed Katz, Patricia Collins, Martin Griss 2011 Carnegie Mellon University

Room-Level Wi-Fi Location Tracking, Joshua Correa, Ed Katz, Patricia Collins, Martin Griss

Martin L Griss

Context-aware applications for indoor intelligent environments require an appropriately accurate and stable interior positioning system to adapt services to the location of a mobile user or mobile device in a building. Different technologies provide a varying mix of resolution, accuracy, stability and challenges. In this paper we report on our experience using an existing Wi-Fi infrastructure without specialized hardware added to support location tracking. There are several approaches to track the location of Wi-Fi enabled devices within a building such as signal propagation models and signature matching. We found signature matching most effective in our environment. Signature matching is accomplished …


Development Of A Cubesat Payload To Model Particle Dampening In Space: Design And Implementation Of Software For Cp7, Daniel Walker 2010 California Polytechnic State University - San Luis Obispo

Development Of A Cubesat Payload To Model Particle Dampening In Space: Design And Implementation Of Software For Cp7, Daniel Walker

Computer Engineering

The California Polytechnic State University CubeSat student research & development group, PolySat, is currently in a mature development stage of a single unit CubeSat designated CP7. The CP7 mission implements a scientific payload designed to characterize particle dampers in microgravity conditions. When subjected to vibration, the momentum exchanges and frictional forces of the particles create a damping effect that can be optimized to suit a number of applications over a broad frequency and amplitude range. In space based applications, particle dampers would serve as a robust and simple device to eliminate jitter in optical assemblies and other sensitive instrumentation. This …


An Fpga Based Implementation Of The Exact Stochastic Simulation Algorithm, Phani Bharadwaj Vanguri 2010 University of Tennessee, Knoxville

An Fpga Based Implementation Of The Exact Stochastic Simulation Algorithm, Phani Bharadwaj Vanguri

Masters Theses

Mathematical and statistical modeling of biological systems is a desired goal for many years. Many biochemical models are often evaluated using a deterministic approach, which uses differential equations to describe the chemical interactions. However, such an approach is inaccurate for small species populations as it neglects the discrete representation of population values, presents the possibility of negative populations, and does not represent the stochastic nature of biochemical systems. The Stochastic Simulation Algorithm (SSA) developed by Gillespie is able to properly account for these inherent noise fluctuations. Due to the stochastic nature of the Monte Carlo simulations, large numbers of simulations …


Multi-Threshold Cmos Circuit Design Methodology From 2d To 3d, Ross Josiah Thian 2010 University of Arkansas, Fayetteville

Multi-Threshold Cmos Circuit Design Methodology From 2d To 3d, Ross Josiah Thian

Graduate Theses and Dissertations

A new and exciting approach in digital IC design in order to accommodate the Moore's law is 3D chip stacking. Chip stacking offers more transistors per chip, reduced wire lengths, and increased memory access bandwidths. This thesis demonstrates that traditional 2D design flow can be adapted for 3D chip stacking. 3D chip stacking has a serious drawback: heat generation. Die-on-die architecture reduces exposed surface area for heat dissipation. In order to reduce heat generation, a low power technique named Multi-Threshold CMOS (MTCMOS) was incorporated in this work. MTCMOS required designing a power management unit (to control when and which gates …


Asynchronous Mips Processors: Educational Simulations, Robert L. Webb 2010 California Polytechnic State University, San Luis Obispo

Asynchronous Mips Processors: Educational Simulations, Robert L. Webb

Master's Theses

The system clock has been omnipresent in most mainstream chip designs. While simplifying many design problems the clock has caused the problems of clock skew, high power consumption, electromagnetic interference, and worst-case performance. In recent years, as the timing constraints of synchronous designs have been squeezed ever tighter, the efficiencies of asynchronous designs have become more attractive. By removing the clock, these issues can be mitigated. How- ever, asynchronous designs are generally more complex and difficult to debug. In this paper I discuss the advantages of asynchronous processors and the specifics of some asynchronous designs, outline the roadblocks to asynchronous …


Deterministic, Efficient Variation Of Circuit Components To Improve Resistance To Reverse Engineering, Daniel F. Koranek 2010 Air Force Institute of Technology

Deterministic, Efficient Variation Of Circuit Components To Improve Resistance To Reverse Engineering, Daniel F. Koranek

Theses and Dissertations

This research proposes two alternative methods for generating semantically equivalent circuit variants which leave the circuit's internal structure pseudo-randomly determined. Component fusion deterministically selects subcircuits using a component identification algorithm and replaces them using a deterministic algorithm that generates canonical logic forms. Component encryption seeks to alter the semantics of individual circuit components using an encoding function, but preserves the overall circuit semantics by decoding signal values later in the circuit. Experiments were conducted to examine the performance of component fusion and component encryption against representative trials of subcircuit selection-and-replacement and Boundary Blurring, two previously defined methods for circuit obfuscation. …


Performance Evaluation Of A Field Programmable Gate Array-Based System For Detecting And Tracking Peer-To-Peer Protocols On A Gigabit Ethernet Network, Brennon D. Thomas 2010 Air Force Institute of Technology

Performance Evaluation Of A Field Programmable Gate Array-Based System For Detecting And Tracking Peer-To-Peer Protocols On A Gigabit Ethernet Network, Brennon D. Thomas

Theses and Dissertations

Recent years have seen a massive increase in illegal, suspicious, and malicious traffic traversing government and military computer networks. Some examples include illegal file distribution and disclosure of sensitive information using the BitTorrent file sharing protocol, criminals and terrorists using Voice over Internet Protocol (VoIP) technologies to communicate, and foreign entities exfiltrating sensitive data from government, military, and Department of Defense contractor networks. As a result of these growing threats, the TRacking and Analysis for Peer-to-Peer (TRAPP) system was developed in 2008 to detect BitTorrent and VoIP traffic of interest. The TRAPP system, designed on a Xilinx Virtex-II Pro Field …


5 Ghz Band Vehicle-To-Vehicle Channels: Models For Multiple Values Of Channel Bandwidth, Qiong Wu, David W. Matolak, Indranil Sen 2010 University of South Carolina - Columbia

5 Ghz Band Vehicle-To-Vehicle Channels: Models For Multiple Values Of Channel Bandwidth, Qiong Wu, David W. Matolak, Indranil Sen

Faculty Publications

In Sen and Matolak's earlier paper, 5-GHz-band vehicle-to-vehicle (V2V) channel models were presented for channel bandwidths of 5 and 10 MHz. In this paper, we provide additional tapped delay line models for bandwidths of 1, 20, 33.33, and 50 MHz based upon the data used in Sen and Matolak's paper. We provide tables of channel parameters for five types of V2V channel classes and also include example tap correlation coefficients. Root-mean-square delay spread values are summarized, as are values of bandwidth for which the channel frequency correlation takes values of 0.7 and 0.5. As with the results from Sen and …


Pretty Lights, Nicholas (Nick) delMas, Matthew (Matt) Maniaci 2010 California Polytechnic State University - San Luis Obispo

Pretty Lights, Nicholas (Nick) Delmas, Matthew (Matt) Maniaci

Computer Engineering

Digital media players often include a visualization component that allows a user to watch a visualization synchronized to their music or videos. This project uses the visualization plugin API of an existing media playback program (WinAmp) but it displays its visuals using physical LED lights. Instead of outputting visuals to the computer screen, data is sent over USB to a micro controller that runs the LED lights. This project aims to give users a more visceral visual experience than traditional visualizations on the computer screen.


High Power Microwave (Hpm) And Ionizing Radiation Effects On Cmos Devices, Nicholas A. Estep 2010 Air Force Institute of Technology

High Power Microwave (Hpm) And Ionizing Radiation Effects On Cmos Devices, Nicholas A. Estep

Theses and Dissertations

Integrated circuits (ICs) are inherently complicated and made worse by increasing transistor quantity and density. This trend potentially enhances concomitant effects of high energy radiation and local or impressed electromagnetic interference (EMI). The reduced margin for signal error may counter any gain in radiation hardness from smaller device dimensions. Isolated EMI and ionizing radiation studies on circuits have been conducted extensively over the past 30 years. However, little focus has been placed on the combined effects. To investigate the effect of combined EMI and ionizing radiation, two complementary metal oxide semiconductor (CMOS) inverter technologies (CD4069 and SN74AUC1G04) were analyzed for …


Post Silicon Clock Tuning System To Mitigate The Impact Of Process Variation On Performance, Kelageri Nagaraj 2010 University of Massachusetts Amherst

Post Silicon Clock Tuning System To Mitigate The Impact Of Process Variation On Performance, Kelageri Nagaraj

Masters Theses 1911 - February 2014

Optical shrink for process migration, manufacturing process variation and dynamic voltage control leads to clock skew as well as path delay variation in a manufactured chip. Since such variations are difficult to predict in pre-silicon phase, tunable clock buffers have been used in several microprocessor designs. The buffer delays are tuned to improve maximum operating clock frequency of a design. This however shifts the burden of finding tuning settings for individual clock buffers to the test process. In this project, we describe a process of using tester measurements to determine the settings of the tunable buffers for recovery of performance …


Embedded Systems As Datacenters, Robert Iannucci 2009 RAI Laboratory LLC

Embedded Systems As Datacenters, Robert Iannucci

Robert A Iannucci

No abstract provided.


Using A Majority Voting Hardware Method On Weather Information To Increase The Accuracy Of Decision Making Methods, Sanaz Asadinia 2009 University of Arak,Iran

Using A Majority Voting Hardware Method On Weather Information To Increase The Accuracy Of Decision Making Methods, Sanaz Asadinia

Sanaz Asadinia

No abstract provided.


A Hybrid Routing Algorithm Based On Ant Colony And Zhls Routing Protocol For Manet, Marjan Rafsanjani, Sanaz Asadinia, Farzaneh Pakzad 2009 University of Arak,Iran

A Hybrid Routing Algorithm Based On Ant Colony And Zhls Routing Protocol For Manet, Marjan Rafsanjani, Sanaz Asadinia, Farzaneh Pakzad

Sanaz Asadinia

Mobile Ad hoc networks (MANETs) require dynamic routing schemes for adequate performance. This paper, presents a new routing algorithm for MANETs, which combines the idea of ant colony optimization with Zone-based Hierarchical Link State (ZHLS) protocol. Ant colony optimization (ACO) is a class of Swarm Intelligence (SI) algorithms. SI is the local interaction of many simple agents to achieve a global goal. SI is based on social insect for solving different types of problems. ACO algorithm uses mobile agents called ants to explore network. Ants help to find paths between two nodes in the network. Our algorithm is based on …


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