Computer and Systems Architecture Commons^™

The Changing Patterns Of Internet Usage, Christopher S. Yoo

Federal Communications Law Journal

Symposium: Essays from Time Warner Cable's Research Program on Digital Communications.

The Challenge Of Increasing Broadband Capacity, Dale N. Hatfield

Federal Communications Law Journal

Symposium: Essays from Time Warner Cable's Research Program on Digital Communications.

Data Routing In Multicore Processors Using Dimension Increment Method, Arpita H. Kadakia

UNLV Theses, Dissertations, Professional Papers, and Capstones

A Deadlock-free routing algorithm can be generated for arbitrary interconnection network using the concept of virtual channels but the virtual channels will lead to more complex algorithms and more demands of NOC resource.

In this thesis, we study a Torus topology for NOC application, design its structure and propose a routing algorithm exploiting the characteristics of NOC. We have chosen a typical 16 (4 by 4) routers Torus and propose the corresponding route algorithm. In our algorithm, all the channels are assigned 4 different dimensions (n0,n1,n2 & n3). By following the dimension increment method, we break the dependent route circles, …

Dynamic Distributed Programming And Applications To Swap Edge Problem, Feven Z. Andemeskel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Link failure is a common reason for disruption in communication networks. If communication between processes of a weighted distributed network is maintained by a spanning tree T, and if one edge e of T fails, communication can be restored by finding a new spanning tree, T’. If the network is 2-edge connected, T’ can always be constructed by replacing e by a single edge, e’, of the network. We refer to e’ as a swap edge of e.

The best swap edge problem is to find the best choice of e’, that is, that e which causes the new spanning …

Wireless Sensing Without Sensors: An Experimental Study Of Motion/Intrusion Detection Using Rf Irregularity, Wei Qi Lee, Winston K. G. Seah, Hwee-Pink Tan, Zexi Yao

Research Collection School Of Computing and Information Systems

Motion and intrusion detection are often cited as wireless sensor network (WSN) applications with typical configurations comprising clusters of wireless nodes equipped with motion sensors to detect human motion. Currently, WSN performance is subjected to several constraints, namely radio irregularity and finite on-board computation/energy resources. Radio irregularity in radio frequency (RF) propagation rises to a higher level in the presence of human activity due to the absorption effect of the human body. In this paper, we investigate the feasibility of monitoring RF transmission for the purpose of intrusion detection through experimentation. With empirical data obtained from the Crossbow TelosB platform …

Electroencephalogram Artifact Removal Using A Wavelet Neural Network, Hoang-Anh T. Nguyen

Electrical & Computer Engineering Theses & Dissertations

A wavelet neural network (WNN) technique rs developed for electroencephalogram (EEG) artifact removal without electrooculographic (EOG) recordings. The algorithm combines the universal approximation characteristics of neural networks and the time/frequency property of wavelet, where the neural network was trained on a simulated dataset with known ground truths. The contribution of this thesis is two-fold. First, many EEG artifact removal algorithms, including regression based methods, require reference EOG signals, which are not always available. To remove EEG ai1ifacts, a WNN tries to learn the characteristics of the artifacts first and does not need reference EOG signals once trained. Second, WNNs are …

Knowledge-Based Decision Support In Department Of Defense Acquisitions, Clifton L. Hicks

Theses and Dissertations

Despite numerous reform efforts over the past 30 years, acquisition programs in the Department of Defense (DoD) continue to experience cost overruns and schedule delays. One contributing factor is the decision-making process used by defense officials. The General Accounting Office (GAO) has stated that ‘poor program outcomes are the lack of widespread adoption of a knowledge-based acquisition process within DoD despite polices that support such a process. A knowledge-based business case at the outset of each program would alleviate overpromising on cost, schedule, and performance and would empower program managers.’ Effective decision-making for acquisition programs is very important. It not …

Hardware Implementation Of Real-Time Operating System’S Thread Context Switch, Deepak Kumar Gauba

Boise State University Theses and Dissertations

Increasingly, embedded real-time applications use multi-threading. The benefits of multi-threading include greater throughput, improved responsiveness, and ease of development and maintenance. However, there are costs and pitfalls associated with multi-threading.

In some of hard real-time applications, with very precise timing requirements, multi-threading itself becomes an overhead cost mainly due to scheduling and contextswitching components of the real-time operating system (RTOS). Different scheduling algorithms have been suggested to improve the overall system performance. However, context-switching still consumes much of the processor’s time and becomes a major overhead cost especially for hard real-time embedded systems.

A typical RTOS context switch consumes 50 …

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 …

Informatics And Natural Computation: Final Report, Francis T. Marchese

Cornerstone 3 Reports : Interdisciplinary Informatics

The purpose of this grant is to develop an interdisciplinary course in Informatics and Natural Computation that would service undergraduate computer, natural, and physical science majors. Informatics is the science of information, the practice of information processing, and the engineering of information systems. Informatics studies the structure, algorithms, behavior, and interactions of natural and artificial systems that store, process, access and communicate information. Natural computing refers to a collection of disciplines that unite nature with computing in three distinct ways:

1. Nature serves as a source of inspiration for the development of computational tools or systems that are used for …

Scan Loss Pattern Synthesis For Adaptive Array Ground Stations, William C. Barott, Mary Ann Ingram, Paul G. Steffes

Publications

We present several techniques for maximizing the contact time between low Earth orbiting satellites (LEOs) and a ground station (GS). The GS comprises an adaptive array of electronically steered space-fed lenses (SFLs). Each SFL is manufactured as a low-cost printed circuit with the result that it exhibits scanning loss. By differently orienting the boresights of the SFLs in the adaptive array, the SFL's scanning losses can be made to optimally complement the path loss of the LEO, thereby reducing the cost of the GS while maximizing the download capacity of the satellite link. The optimization, implemented with a genetic algorithm …

Comparing Discrete Simulation And System Dynamics: Modeling An Anti-Insurgency Influence Operation, Wayne Wakeland, Una E. Medina

Complex Systems Faculty Publications and Presentations

This paper contrasts the tradeoffs of modeling the same dynamic problem at a micro scale and at a macro scale of analysis: discrete system simulation (DS) versus continuous system simulation or system dynamics (SD). Both are employed to model the influence of entertainment education on terrorist system decay, with implications for field application. Each method optimizes different design, scope/scale, data availability/accuracy, parameter settings, and system sensitivities. Whether the research served by the computer model is applied or theoretical, DS tends to be useful for understand low-level individual unit/step influences on system change over time, whereas SD tends to shine when …

System Dynamics Implementation Of An Extended Brander And Taylor-Like Easter Island Model, Takuro Uehara, Yoko Nagase, Wayne Wakeland

Complex Systems Faculty Publications and Presentations

We provide a system dynamics implementation of a dynamic ecological economics model. Dynamic economic models are often constrained to use functions, such as the Cobb-Douglas function, chosen “conveniently” to allow for analytic solutions. The C-D function, however, suffers from its fixed elasticity that does not allow for the substitutability between man-made capital and natural capital to change, which is vital for economic sustainability. Using system dynamics removes this constraint and enables more realistic ecological economics models containing functions not amenable to analytic solution. The base model is the natural resource and population growth model developed by Brander and Taylor (1998) …

Developing A Hybrid Virtualization Platform Design For Cyber Warfare And Simulation, Kyle E. Stewart

Theses and Dissertations

Virtualization is a technique used to model and simulate the cyber domain, as well as train and educate. Different types of virtualization techniques exist that each support a unique set of benefits and requirements. This research proposes a novel design that incorporates host and network virtualization concepts for a cyber warfare training platform. At the host level, hybrid virtualization combines full and operating system virtualization techniques in order to leverage the benefits and minimize the drawbacks of each individual technique. Network virtualization allows virtual machines to connect in flexible topologies, but it also incurs additional processing overhead. Quantitative analysis falls …

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 …

A Dynamically Configurable Log-Based Distributed Security Event Detection Methodology Using Simple Event Correlator, Justin M. Myers

Theses and Dissertations

Log event correlation is an effective means of detecting system faults and security breaches encountered in information technology environments. Centralized, database-driven log event correlation is common, but suffers from flaws such as high network bandwidth utilization, significant requirements for system resources, and difficulty in detecting certain suspicious behaviors. This research presents a distributed event correlation system which performs security event detection, and compares it with a centralized alternative. The comparison measures the value in distributed event correlation by considering network bandwidth utilization, detection capability and database query efficiency, as well as through the implementation of remote configuration scripts and correlation …

Mission Assurance: A Review Of Continuity Of Operations Guidance For Application To Cyber Incident Mission Impact Assessment (Cimia), Brian L. Hale

Theses and Dissertations

Military organizations have embedded information technology (IT) into their core mission processes as a means to increase operational efficiency, improve decision-making quality, and shorten the sensor-to-shooter cycle. This IT-to-mission dependence can place the organizational mission at risk when an information incident (e.g., the loss or manipulation of a critical information resource) occurs. Non-military organizations typically address this type of IT risk through an introspective, enterprise-wide focused risk management program that continuously identifies, prioritizes, and documents risks so an economical set of control measures (e.g., people, processes, technology) can be selected to mitigate the risks to an acceptable level. The explicit …

Ultrasonic Shark-Tag Locator System For Iver2 Auv, Nathaniel Garcia

Computer Engineering

The purpose of this project is to develop a system for tracking an ultrasonic underwater transmitter that can be integrated into an IVER2 AUV to allow it to follow and monitor tagged sharks in the ocean for scientific research.

The system consists of a four main components including a shark-tag, two hydrophones, a filter/amplifier & threshold detector circuit, and a microcontroller.

This project, while not completing field testing and integration with the IVER2, is a proof of concept of a system that utilizes passive sonar to determine a bearing from the system to a shark-tag transmitter. Additionally, it devised several …

Max Flow Spill Code Placement Algorithm Implemented In Gcc 4.4.3, Stephen Robert Beard

Computer Engineering

The placement of spill code plays an important role in the register allocator of an optimizing compiler. Many computer architectures possess a register linkage convention that dictates which registers are preserved across function calls and which are not. This project addresses the problem of optimizing spill code that is associated with register linkage conventions.

This algorithm was created by Dr. Chris Lupo and is described in the paper Beyond Register Allocation: a Novel Algorithm for Spill-Code Placement. The algorithm was implemented for GCC 2.5.7 for a PA-RISC architecture [4]. The work in this project will involve porting the existing code …

Rfid Asset Tracking And Digital Check-Out System, Jeffrey (Jeff) Migliore

Computer Engineering

An asset tracking and digital check-out system was developed using Radio Frequency Identification (RFID) and a Single Board Computer (SBC). A RFID reader was used as a check point to process transactions. The RFID reader was attached to the SBC via USB. The SBC is integrated into a network via Ethernet and hosts a web graphical user interface (GUI) frontend for users to view transactions and query availability of assets. A MYSQL database was used for the backend storage of data.

Specifically, this system was designed to track tool assets. Many modern companies have employees sharing limited resources. The common …