Computer Engineering Commons^™

Coordinated Control And Estimation Of Multiagent Systems With Engineering Applications, Housheng Su, Michael Z.Q. Chen, Qing Hui, Wei Zhang, Fanglai Zhu

Department of Electrical and Computer Engineering: Faculty Publications

Recently, coordinated control and estimation problems have attracted a great deal of attention in different fields especially in biology, physics, computer science, and control engineering. Coordinated control and estimation problems have prominent characteristics of distributed control, local interaction, and self-organization. Research on multiagent coordinated control and estimation problems not only helps better understand the mechanisms of natural collective phenomena but also benefits the applications of cyberphysical systems.

This special issue focuses on theoretical and technological achievements in cooperative multiagent Systems. It contains twenty-six papers, the contents of which are summarized below.

A Performance Study Of Genetic Algorithm-Assisted Beamforming In Distributed Cognitive Radio Networks, Andrew Minturn

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

Cognitive Radio (CR) is a technology that has gained much interest recently due to the increasing scarcity of the radio frequency spectrum. Large portions of the radio frequency spectrum are licensed to users who then have exclusive access to the bandwidth, and unlicensed bands can be a challenge to use due to interference from unlicensed users. Despite the seeming scarcity, tests of bands allocated by the Federal Communications Committee (FCC) to licensed and unlicensed user have shown that many are underutilized and often unoccupied by the user to whom they are licensed. CR aims to exploit this unused spectrum and …

A Comparative Study Of Generalized Arc-Consistency Algorithms, Olufikayo S. Adetunji

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

In this thesis, we study several algorithms for enforcing Generalized Arc­-Consistency (GAC), which is the most popular consistency property for solving Constraint Satisfaction Problems (CSPs) with backtrack search. The popularity of such algorithms stems from their relative low cost and effectiveness in improving the performance of search. Virtually all commercial and public- domain constraint solvers include some implementation of a generic GAC algorithm. In recent years, several algorithms for enforcing GAC have been proposed in the literature that relies on increasingly complex data structures and mechanisms to improve performance. In this thesis, we study, assess, and compare a basic algorithm …

Stable And Metastable Nanowires Displaying Locally Controllable Properties, Eli A. Sutter, Peter Werner Sutter

Department of Electrical and Computer Engineering: Faculty Publications

(57) ABSTRACT Vapor-liquid-solid growth of nanowires is tailored to achieve complex one-dimensional material geometries using phase diagrams determined for nanoscale materials. Segmented one-dimensional nanowires having constant composition dis play locally variable electronic band structures that are deter mined by the diameter of the nanowires. The unique electrical and optical properties of the segmented nanowires are exploited to form electronic and optoelectronic devices. Using gold-germanium as a model system, in situ transmis sion electron microscopy establishes, for nanometer-sized Au Ge alloy drops at the tips of Ge nanowires (NWs), the parts of the phase diagram that determine their temperature dependent equilibrium …

Designing A Bayer Filter With Smooth Hue Transition Interpolation Using The Xilinx System Generator, Zhiqiang Li, Peter Revesz

CSE Conference and Workshop Papers

This paper describes the design of a Bayer filter with smooth hue transition using the System Generator for DSP. We describe and compare experimentally two different designs, one based on a MATLAB implementation and the other based on a modification of the Bayer filter using bilinear interpolation.

A Game-Theoretic Analysis Of The Nuclear Non-Proliferation Treaty, Peter Revesz

CSE Conference and Workshop Papers

Although nuclear non-proliferation is an almost universal human desire, in practice, the negotiated treaties appear unable to prevent the steady growth of the number of states that have nuclear weapons. We propose a computational model for understanding the complex issues behind nuclear arms negotiations, the motivations of various states to enter a nuclear weapons program and the ways to diffuse crisis situations.

Estimating The Flight Path Of Moving Objects Based On Acceleration Data, Peter Revesz

CSE Conference and Workshop Papers

Inertial navigation is the problem of estimating the flight path of a moving object based on only acceleration measurements. This paper describes and compares two approaches for inertial navigation. Both approaches estimate the flight path of the moving object using cubic spline interpolation, but they find the coefficients of the cubic spline pieces by different methods. The first approach uses a tridiagonal matrix, while the second approach uses recurrence equations. They also require different boundary conditions. While both approaches work in O(n) time where n is the number of given acceleration measurements, the recurrence equation-based method can be easier updated …

Cubic Spline Interpolation By Solving A Recurrence Equation Instead Of A Tridiagonal Matrix, Peter Revesz

CSE Conference and Workshop Papers

The cubic spline interpolation method is proba- bly the most widely-used polynomial interpolation method for functions of one variable. However, the cubic spline method requires solving a tridiagonal matrix-vector equation with an O(n) computational time complexity where n is the number of data measurements. Even an O(n) time complexity may be too much in some time-ciritical applications, such as continuously estimating and updating the flight paths of moving objects. This paper shows that under certain boundary conditions the tridiagonal matrix solving step of the cubic spline method could be entirely eliminated and instead the coefficients of the unknown cubic polynomials …

A Comparative Study Of Underwater Robot Path Planning Algorithms For Adaptive Sampling In A Network Of Sensors, Sreeja Banerjee

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Monitoring lakes, rivers, and oceans is critical to improving our understanding of complex large-scale ecosystems. We introduce a method of underwater monitoring using semi-mobile underwater sensor networks and mobile underwater robots in this thesis. The underwater robots can move freely in all dimension while the sensor nodes are anchored to the bottom of the water column and can move only up and down along the depth of the water column. We develop three different algorithms to optimize the path of the underwater robot and the positions of the sensors to improve the overall quality of sensing of an area of …

Expected Cost Penalty Due To Deviation From Security-Constrained Dispatch, Veravut Dheraprasart

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

This thesis introduces and evaluates a new index called ”Expected Cost Penalty Due to Deviation From Security Constrained Dispatch” (ECP_SCD) for interconnected power systems planning. This index represents the optimal operating cost of the system taking into account the uncertainties such as random failure of generating units, transformer, and transmission lines in interconnected power systems. The significance of this index is that it represents the minimum operating cost for a contingency event and can be used for contingency screening (ranking). This index also indicates the impact of equipment reliability on the average cost penalty of all contingency events. Moreover, this …

A Methodology And Tool For Concurrent Fault Injection, Zhongyin Zhang

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

As the speed of microprocessors tails off, utilizing multiple processing cores per chip is becoming a common way for developers to achieve higher performance. However, writing concurrent programs can be a big challenge because of common concurrency faults. Because concurrency faults are hard to detect and reproduce, traditional testing techniques are not suitable. New techniques are needed, and these must be assessed. A typical method for assessing testing techniques is to embed faults in programs using mutation tools, and assess the ability of techniques to detect these. Although mutation testing techniques can be used to represent common faults, approaches for …

Performance Analysis Of Mobile Ad-Hoc Routing Protocols By Varying Mobility, Speed And Network Load, Nilotpal Sarmah

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

One of the most promising network that has emerged from the technology world is the mobile ad-hoc network or MANET. It is a type of multi-hop network. Wireless by nature, MANETs do not have a specific network infrastructure. It is a collection of wireless mobile devices that communicate with each other without the help of any third party backbone like a base-station or a router. It can be hard to imagine how every node in this type of network communicate with one another without having a router. In MANETs, nodes change locations with time, configure themselves and get the information …

Growth Of Graphene Films And Graphene Patterns, Yongfeng Lu, Wei Xiong, Yunshen Zhou

Department of Electrical and Computer Engineering: Faculty Publications

Large area graphene can be fabricated by depositing carbon and catalytic metal thin film(s) on a substrate, heating the carbon and the catalytic metal, and forming graphene on the substrate. The catalytic metal is evaporated during the heating process. The catalytic metal can be, for example, nickel, cobalt, or iron.

Measuring Autonomy And Solving General Stabilization Problems With Multi-Agent Systems, Rasheed A. Rajabzadeh

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Many distributed complex problems address a particular form of resource scheduling where proper resource management can cut costs by stabilizing a set of stochastic fluctuating parameters. Wireless sensor network communication, supply chain management, stock trading, intelligent traffic management, and smart grid systems are examples of these problems. Among the various solutions, a common strategy often used to address this type of problems is fluctuation reduction via resource buffering combined with load shifting. Respectively, stable wireless communication, demand for supplies, liquidity, traffic speed, and power demand reduce cost and can be achieved by properly managing sensor data buffers, warehouses, capital, distance …

Thickness Determination Of Few-Layer Hexagonal Boron Nitride Films By Scanning Electron Microscopy And Auger Electron Spectroscopy, P. Sutter, E. Sutter

Department of Electrical and Computer Engineering: Faculty Publications

We assess scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) for thickness measurements on few-layer hexagonal boron nitride (h-BN), the layered dielectric of choice for integration with graphene and other two-dimensional materials. Observations on h-BN islands with large, atomically flat terraces show that the secondary electron intensity in SEM reflects monolayer height changes in films up to least 10 atomic layers thickness. From a quantitative analysis of AES data, the energy-dependent electron escape depth in h-BN films is deduced. The results show that AES is suitable for absolute thickness measurements of few-layer h-BN of 1 to 6 layers.

Self-Organizing Microstructures Orientation Control In Femtosecond Laser Patterning On Silicon Surface, Pengjun Liu, Lan Jiang, Jie Hu, Shuai Zhang, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Self-organizing rippled microstructures are induced on silicon surface by linearly polarized femtosecond laser pulses. At a near threshold fluence, it is observed that ripple orientation is co-determined by the laser polarization direction and laser scanning parameters (scanning direction and scanning speed) in surface patterning process. Under fixed laser polarization, the ripple orientation can be controlled to rotate by about 40° through changing laser scanning parameters. In addition, it is also observed that the ripple morphology is sensitive to the laser scanning direction, and it is an optimal choice to obtain ordered ripple structures when the angle between laser scanning and …

Human Brain Networks: Spiking Neuron Models, Multistability, Synchronization, Thermodynamics, Maximum Entropy Production, And Anesthetic Cascade Mechanisms, Wassim H. Haddad, Qing Hui, James M. Bailey

Department of Electrical and Computer Engineering: Faculty Publications

Advances in neuroscience have been closely linked to mathematical modeling beginning with the integrate-and-fire model of Lapicque and proceeding through the modeling of the action potential by Hodgkin and Huxley to the current era. The fundamental building block of the central nervous system, the neuron, may be thought of as a dynamic element that is “excitable”, and can generate a pulse or spike whenever the electrochemical potential across the cell membrane of the neuron exceeds a threshold. A key application of nonlinear dynamical systems theory to the neurosciences is to study phenomena of the central nervous system that exhibit nearly …

Ultimate Codes: Near-Optimal Mds Array Codes For Raid-6, Zhijie Huang, Hong Jiang, Chong Wang, Ke Zhou, Yuhong Zhao

CSE Technical Reports

As modern storage systems have grown in size and complexity, RAID-6 is poised to replace RAID-5 as the dominant form of RAID architectures due to its ability to protect against double disk failures. Many excellent erasure codes specially designed for RAID-6 have emerged in recent years. However, all of them have limitations. In this paper, we present a class of near perfect erasure codes for RAID-6, called the Ultimate codes. These codes encode, update and decode either optimally or nearly optimally, regardless of what the code length is. This implies that utilizing these codes we can build highly efficient and …

S-Code: Lowest Density Mds Array Codes For Raid-6, Zhijie Huang, Hong Jiang, Ke Zhou, Yuhong Zhao, Chong Wang

CSE Technical Reports

RAID, a storage architecture designed to exploit I/O parallelism and provide data reliability, has been deployed widely in computing systems as a storage building block. In large scale storage systems, in particular, RAID-6 is gradually replacing RAID-5 as the dominant form of disk arrays due to its capability of tolerating concurrent failures of any two disks. MDS (maximum distance separable) array codes are the most popular erasure codes that can be used for implementing RAID-6, since they enable optimal storage efficiency and efficient encoding and decoding algorithms. In this paper, we propose a new class of MDS array codes called …

Invariant Inferring And Monitoring In Robotic Systems, Hengle Jiang

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

System monitoring can help to detect abnormalities and avoid failures. Crafting monitors for today’s robotic systems, however, can be very difficult due to the systems’ inherent complexity and its rich operating environment.

In this work we address this challenge through an approach that automatically infers system invariants and synthesizes those invariants into monitors. This approach is inspired by existing software engineering approaches for automated invariant inference, and it is novel in that it derives invariants by observing the messages passed between system nodes and the invariants types are tailored to match the spatial, time, temporal, and architectural attributes of robotic …

Anisotropy Modulations Of Femtosecond Laser Pulse Induced Periodic Surface Structures On Silicon By Adjusting Double Pulse Delay, Weina Han, Lan Jiang, Xiaowei Li, Qingsong Wang, Hao Li, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

We demonstrate that the polarization-dependent anisotropy of the laser-induced periodic surface structure (LIPSS) on silicon can be adjusted by designing a femtosecond laser pulse train (800 nm, 50 fs, 1 kHz). By varying the pulse delay from 100 to 1600 fs within a double pulse train to reduce the deposited pulse energy, which weakens the directional surface plasmon polarition (SPP)-laser energy coupling based on the initial formed ripple structure, the polarization-dependent geometrical morphology of the LIPSS evolves from a nearly isotropic circular shape to a somewhat elongated elliptical shape. Meanwhile, the controllable anisotropy of the two-dimensional scanned-line widths with different …

Power Management In The Cluster System, Leping Wang

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

With growing cost of electricity, the power management of server clusters has become an important problem. However, most previous researchers have only addressed the challenge in traditional homogeneous environments. Considering the increasing popularity of heterogeneous and virtualized systems, this thesis develops a series of efficient algorithms respectively for power management of heterogeneous soft real-time clusters and a virtualized cluster system. It is built on simple but effective mathematical models. When deployed to a new platform, the software incurs low configuration cost because no extensive performance measurements and profiling are required. Built upon optimization, queuing theory and control theory techniques, our …

Processing Of Monolayer Materals Vlanterfacial Reactions, Peter Werner Sutter, Eli Anguelova Sutter

Department of Electrical and Computer Engineering: Faculty Publications

A method of forming and processing of graphene is disclosed based on exposure and selective intercalation of the partially graphene-covered metal Substrate with atomic or molecular intercalation species such as oxygen (O) and nitrogen oxide (NO). The process of intercalation lifts the strong metal carbon coupling and restores the characteristic Dirac behav ior of isolated monolayer graphene. The interface of graphene with metals or metal-decorated substrates also provides for controlled chemical reactions based on novel functionality of the confined space between a metal Surface and a graphene sheet.

Volunteered Geographical Information: An Alternative Solution For Overcoming The Chasm Between Stormwater Management And Community Participation, Yanfu Zhou

Community and Regional Planning Program: Theses and Student Projects

It is a dramatic challenge to promote public engagement in stormwater management and green infrastructure initiatives. When traditional outreach approaches made important influence on public engagement, their limitations are also obvious. With the development of Web 2.0 technology, Volunteered Geographic Information (VGI) has been emerging as one of the most important user-generated geographic contents. The crowdsourcing data that generated by volunteers through geo-web, smartphones, and other geo-devices provides invaluable mass data for decision-making. VGI can provide a better understanding of planning issues and other challenges. The research aims to develop a mobile information platform to allow citizens to report the …

Decaf: A New Event Detection Logic For The Purpose Of Fusing Delineated-Continuous Spatial Information, Kerry Q. Hart

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Geospatial information fusion is the process of synthesizing information from complementary data sources located at different points in space and time. Spatial phenomena are often measured at discrete locations by sensor networks, technicians, and volunteers; yet decisions often require information about locations where direct measurements do not exist. Traditional methods assume the spatial phenomena to be either discrete or continuous, an assumption that underlies and informs all subsequent analysis. Yet certain phenomena defy this dichotomy, alternating as they move across spatial and temporal scales. Precipitation, for example, appears continuous at large scales, but it can be temporally decomposed into discrete …

Variable Bounds Analysis Of A Climate Model Using Software Verification Techniques, Peter Revesz, Robert Woodward

CSE Conference and Workshop Papers

Software verification techniques often use some approximation method that identifies the limits of the possible range of values that variables in a computer program can take during execution. Current climate models are complex computer programs that are typically iterated time-step by time-step to predict the next value of the climate-related variables. Because these iterative methods are necessarily computed only for a fixed number of iterations, they are unable to answer many long-range questions that may be posed regarding climate change, for example, whether there are natural fluctuations or whether a tipping point is reached after which there is no return …

Dnn: A Distributed Namenode Filesystem For Hadoop, Ziling Huang

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

The Hadoop Distributed File System (HDFS) is the distributed storage infrastructure for the Hadoop big-data analytics ecosystem. A single node, called the NameNode of HDFS stores the metadata of the entire file system and coordinates the file content placement and retrieval actions of the data storage subsystems, called DataNodes. However the single NameNode architecture has long been viewed as the Achilles' heel of the Hadoop Distributed file system, as it not only represents a single point of failure, but also limits the scalability of the storage tier in the system stack. Since Hadoop is now being deployed at increasing scale, …

Using A Uav To Effectively Prolong Wireless Sensor Network Lifetime With Wireless Power Transfer, Jinfu Leng

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Wireless sensor networks are widely used for everything from border security to monitoring waterway pollution. Supplying energy for long term deployment is a main challenge in the applications of wireless sensor networks, as batteries are the primary energy source. Current wireless sensor networks deployed for long periods either require additional infrastructure, such as solar panels, or periodic maintenance. Our research lab has proposed a novel solution that uses a micro unmanned aerial vehicle (UAV) to wirelessly charge the sensor nodes and prolong the sensor network lifetime. Recent studies have shown that significant power can be transferred wirelessly over medium distances. …

Security Analysis Of Phasor Measurement Units In Smart Grid Communication Infrastructures

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

Phasor Measurement Units (PMUs), or synchrophasors, are rapidly being deployed in the smart grid with the goal of measuring phasor quantities concurrently from wide area distribution substations. By utilizing GPS receivers, PMUs can take a wide area snapshot of power systems. Thus, the possibility of blackouts in the smart grid, the next generation power grid, will be reduced. As the main enabler of Wide Area Measurement Systems (WAMS), PMUs transmit measured values to Phasor Data Concentrators (PDCs) by the synchrophasor standard IEEE C37.118. IEC 61850 and IEC 62351 are the communication protocols for the substation automation system and the security …

Analysis, Optimization, And Implementation Of A Uav-Based Wireless Power Transfer System, Andrew Mittleider

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Wireless power transfer is rapidly advancing in its ability to efficiently transfer power to a variety of devices.

As the efficiency increases, more applications for these systems arise. Since magnetic resonant wireless power transfer can only transfer a small amount of power, most current applications only focus on powering low-powered devices.

Wireless Sensor Networks are composed of many low-powered nodes which currently require human interaction to remain powered. We propose recharging a low-powered Wireless Sensor Network (WSN) with a magnetic resonant wireless power transfer system attached to a quadrotor Unmanned Aerial Vehicle (UAV).

This thesis addresses three main challenges with …