Network flows in Real-Time (RT) systems need to meet stringent end-to-end deadlines in order for such systems to operate safely and reliably. Today, such systems use custom or domain specific network system designs to meet end-to-end deadlines and other constraints of real-time flows. In this work we explore the design...
There are five main contributions of this dissertation. The first contribution is new closed-form expressions for channel capacity of a new class of channel matrices. The second contribution is the discovery of the structure for optimal binary quantizer and the associated methods for finding an optimal quantizer that maximizes mutual...
Throughput-oriented processors, such as graphics processing units (GPUs), have been increasingly used to accelerate general purpose computing, including machine learning models that are being utilized in numerous disciplines. Thousands of concurrently running threads in a GPU demand a highly efficient memory subsystem for data supply in GPUs. In this dissertation,...
This dissertation proposes the use of advanced time-varying approaches for modeling the dynamics of the multipath channel in wireless communication networks. These advanced time-varying approaches include linear Kalman innovation models in observable block companion form, and neural network-based models. The e˙ectiveness of these type of models is evaluated through three...
The ubiquity of high quality video and proliferation of mobile devices has contributed to an unprecedented rise in video consumption. HTTP, in conjunction with adaptive streaming, has become the de facto mechanism for delivering the vast majority of video as it readily caters to heterogeneous networks and devices. This dissertation...
In this dissertation, we explored multiple coding techniques to reduce energy consumption, improve performance, and secure wireless sensor networks specifically and ad-hoc networks in general. With the introduction of Internet of Things (IoT) and 5G technologies, wireless sensor networks are quickly emerging as an important and key technology in the...
Traditional approaches to streaming H.264 video over a network typically rely on a single method of transport (i.e., reliable or unreliable) and/or use static values for parameters that can have a significant negative impact on the perceptual quality of the received video. This dissertation presents a dynamic method for wireless...
Tree-like patterns are ubiquitous in nature. Botanical trees, river networks, and blood systems are the most well-known examples of complex hierarchical systems met in observations. Interestingly, many of such systems exhibit statistical self-similarity. There are two main types of self-similarity: Horton self-similarity and Tokunaga self-similarity. Although there is an increased...
Modern sensor network applications are often implemented wirelessly in order to lessen installation costs and reduce deployment times. Unfortunately, these wireless sensor network (WSN) nodes must often rely on batteries or energy harvesting techniques in order to sustain their operation and supply the power needed to maintain communication within the...
Artificial Intelligence (AI) planning techniques have been central to automating a gamut of tasks from the mundane route planning and beer production to the ethereal image processing of space-ship images. Of all the planning techniques, hierarchical- decomposition planning has been the technique most employed in industrial-strength planners. Hierarchical-decomposition planning is...
Energy consumption has become a great deal for cloud service providers due to financial as well as environmental concerns. Studies show that cloud servers operate, most of the time, at only between 10% and 50% of their maximal utilizations. These same studies also show that servers that are kept ON...
In this work, we study network coding technique, its relation to random matrices, and their applications to communication systems. The dissertation consists of three main contributions. First, we propose efficient algorithms for data synchronization via a broadcast channel using random network coding. Second, we study the resiliency of network coding...
The widespread use of wireless devices that we have recently been witnessing, such as smartphones, tablets, laptops, and wirelessly accessible devices in general, is causing an unprecedented growth in the required amount of the wireless radio spectrum. On the other hand, the spectrum resource has, for the last several decades,...
IO transactions within a computer system have evolved along with other system components (i.e., CPU, memory, video) from programmed IO (PIO). In current mainstream systems (spanning from HPC to mobile) the IO transactions are CPU-centric descriptor-based DMA transactions. The key benefit is that slower IO devices can DMA write system...
Parallel solutions for two classes of linear programs are
presented. First we parallelized the two-phase revised simplex
algorithm and showed that it is possible to get linear improvement in
performance. The simplex algorithm is the best known algorithm for
solving linear programs, and we claim our result is the best...
Two new medium access protocols for ring type local area networks,
CTR (Concurrent Token Ring) protocol and DRUID (Destination Removal
withoUt Intermediate node Delay) ring protocol, are proposed, designed and
analyzed. A destination partial removal technique is designed and used in
these two protocols to support concurrent message transmission and...
Network coding, as the next generation of data routing protocols, enables each intermediate node in a network to process and encode its received data before forwarding it to the next nodes. Hence, the core idea in network coding is to allow a network to encode the data that is being...
Parallel programming is the major stumbling block preventing the parallel processing industry from quickly satisfying the demand for parallel computer software. This research is aimed at solving some of the problems of software development for parallel computers. ELGDF is a graphical language for designing parallel programs. The goal of ELGDF...
Relational database systems have successfully solved many
business data processing problems. The primary reason of this
success is that the relational data model provides a simple, yet
flexible view of data as tables. In studying VLSI/CAD data, we noticed
that they are often represented in formats similar to relational
tuples....
The practice of literate programming is not widespread because existing literate programming systems have some undesirable characteristics such as programming language and text processor dependence and lack of flexible tools for viewing and manipulation of the source file. This dissertation describes the literate programming system AOPS (Abstraction Oriented Programming System)...
An active object system is a transition-based object-oriented system suitable for the design of various concurrent systems. An AOS consists of a collection of interacting objects, where the behavior of each object is determined by the transition statements provided in the class of that object. A transition statement is a...
We consider the parallelization of Monte Carlo algorithms for analyzing numerical models of charge transport used in semiconductor device physics. Parallel algorithms for the standard k-space Monte Carlo simulation of a three band model of bulk GaAs on hypercube multicomputers are first presented. This Monte Carlo model includes scattering due...
The general problem of application development of interactive GUI applications has been addressed by toolkits, libraries, user interface management systems, and more recently domain-specific application frameworks. However, the most sophisticated solution offered by frameworks still lacks a number of features which are addressed by this research: 1) limited functionality --...
Multiparadigm languages are languages that are designed to support more than one style of programming. Leda is a strongly-typed multiparadigm programming language that supports imperative, functional, object-oriented, and logic programming. The constraint programming paradigm is a declarative style of programming where the programmer is able to state relationships among some...
Reinforcement Learning (RL) is the study of learning agents that improve
their performance from rewards and punishments. Most reinforcement learning
methods optimize the discounted total reward received by an agent, while, in many
domains, the natural criterion is to optimize the average reward per time step. In this
thesis, we...
I introduce a compositional approach to application software development. In this approach, an extended entity-relationship diagram (EERD), which represents the component types and the relationship types within an application domain, is used as a template of executable programs in that application domain. As we use structural active objects as the...
The appropriate separation of concerns is a fundamental engineering principle. A concern, for software developers, is that which must be represented by code in a program; by extension, separation of concerns is the ability to represent a single concern in a single appropriate programming language construct. Advanced separation of concerns...
A distributed system is a network of multiple autonomous computational nodes designed primarily for performance scalability and robustness. The performance of a distributed system depends critically on how tasks and resources are distributed among the nodes. Thus, a main thrust in distributed system research is to design schemes for distributing...
In networked control systems (NCS) information or packets usually flow from a
sensor or a set of sensors to a remotely located controller. Then the controller
processes the received information and sends a series of control commands to the
actuators through a communication network which could be either wireless or...
We investigate a number of techniques for increasing throughput and quality of media applications over wireless networks. A typical media communication application such as video streaming imposes strict requirements on the delay and throughout of its packets, which unfortunately, cannot be guaranteed by the underlying wireless network due inherently to...
Error correction codes (ECCs) have been widely used in communication systems and storage devices. Nowadays, the rapid development of integrated circuit technologies makes feasible the implementation of powerful ECCs such as turbo code and low-density parity-check (LDPC) code. However, these high-performance codes require complex decoding algorithms, resulting in large hardware...
General purpose computer systems have seen increased performance potential through the parallel processing capabilities of multicore processors. Yet this potential performance can only be attained through parallel applications, thus forcing software developers to rethink how everyday applications are designed. The most readily form of Thread Level Parallelism (TLP) within any...
Multiparadigm programming languages are a recent development in the realm of programming languages. A multiparadigm programming language allows the use of multiple, differing programming paradigms without departing from a single, unified linguistic framework. Multiparadigm programming languages are claimed to have benefits to both pedagogy and complex application creation. The beneficial...
Dynamic CMOS circuits are commonly used in high-performance memory arrays to implement wide-NOR logic functions for their read and search operations. This is because dynamic circuits have significantly higher speed and lower area compared to static circuits for performing similar operations. Register File (RF) arrays are located at the top...
In its simplest form, the process of diagnosis is a decision-making process in which the diagnostician performs a sequence of tests culminating in a diagnostic decision. For example, a physician might perform a series of simple measurements (body tem- perature, weight, etc.) and laboratory measurements (white blood count, CT scan,...
Wireless Networks have been widely adopted into a major part of today's network infrastructure. They have become a popular technology to not only expand the coverage of wired networks but also to interconnect a large wireless network, i.e., wireless mesh networks. As they allow more flexible communication than traditional wired-networks...
Low-Density Parity-check (LDPC) codes have attracted considerable attention due to their capacity approaching performance over AWGN channel and highly parallelizable decoding schemes. They have been considered in a variety of industry standards for the next generation communication systems. In general, LDPC codes achieve outstanding performance with large codeword lengths (e.g.,...
Accessing information on the Web has become ingrained into our daily lives, and we seek information from many different sources, including conference and journal publications, personal web pages, and others. Increasingly, web-based information retrieval systems such as web-based search engines, library on-line catalog systems, and subscription-based federated search systems are...
Cryptographic devices leak timing and power consumption information that is easily measurable, radiation of various levels, and more. Such devices also have additional inputs, other than plaintext and keys, like voltage, which can be modified to force the device to produce certain faulty outputs that can be used to reveal...