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Full-Text Articles in Engineering
Spatiotemporal Databases: Models For Attracting Students To Research, Ágnes Bércesné Novák, Peter Revesz, Zsolt Tuza
Spatiotemporal Databases: Models For Attracting Students To Research, Ágnes Bércesné Novák, Peter Revesz, Zsolt Tuza
CSE Conference and Workshop Papers
In higher education professors often make much effort to introduce their students to research. Unfortunately, the present standard database systems curriculum is composed of well-settled subjects that do not lead to research. The challenge is to bring the research frontier closer to students at beginner level. In this paper we describe how it can be done in the area of spatiotemporal databases. We propose a new database systems curriculum and illustrate its benefits by mentioning several highly succsesful student projects in some recent experimental introductory database systems courses that followed the new curriculum.
Vector Dissipativity Theory For Discrete-Time Large-Scale Nonlinear Dynamical Systems, Wassim M. Haddad, Qing Hui, Vijaysekhar Chellaboina, Sergey Nersesov
Vector Dissipativity Theory For Discrete-Time Large-Scale Nonlinear Dynamical Systems, Wassim M. Haddad, Qing Hui, Vijaysekhar Chellaboina, Sergey Nersesov
Department of Electrical and Computer Engineering: Faculty Publications
In analyzing large-scale systems, it is often desirable to treat the overall system as a collection of interconnected subsystems. Solution properties of the large-scale system are then deduced from the solution properties of the individual subsystems and the nature of the system interconnections. In this paper, we develop an analysis framework for discrete-time large-scale dynamical systems based on vector dissipativity notions. Specifically, using vector storage functions and vector supply rates, dissipativity properties of the discrete-time composite large-scale system are shown to be determined from the dissipativity properties of the subsystems and their interconnections. In particular, extended Kalman-Yakubovich-Popov conditions, in terms …
Design And Development Of A Low-Cost High Range Resolution X-Band Radar, Paul C. Cantu
Design And Development Of A Low-Cost High Range Resolution X-Band Radar, Paul C. Cantu
Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research
Synthetic Aperture Radar (SAR) is one of the main tools for microwave remote sensing because of its multi-dimensional high resolution characteristics and the capability to operate in nearly all weather conditions, day and night. The University of Nebraska-Lincoln (UNL) initiated the design and development of a low-cost airborne SAR in January 2001 to support our Airborne Remote Sensing Program. The objectives of this project are separated into various evolutionary stages. This thesis will focus on the initial phase of design and construction of an X-band high range resolution radar (HRR) using basic RF /microwave and digital components. The following stages …
Progress In Spectroscopic Ellipsometry: Applications From Vacuum Ultraviolet To Infrared, James N. Hilfiker, Corey L. Bungay, Ron A. Synowicki, Thomas E. Tiwald, Craig M. Herzinger, Blaine Johs, Greg K. Pribil, John A. Woollam
Progress In Spectroscopic Ellipsometry: Applications From Vacuum Ultraviolet To Infrared, James N. Hilfiker, Corey L. Bungay, Ron A. Synowicki, Thomas E. Tiwald, Craig M. Herzinger, Blaine Johs, Greg K. Pribil, John A. Woollam
Department of Electrical and Computer Engineering: Faculty Publications
Spectroscopic ellipsometry (SE) is a noncontact and nondestructive optical technique for thin film characterization. In the past 10 yr, it has migrated from the research laboratory into the semiconductor, data storage, display, communication, and optical coating industries. The wide acceptance of SE is a result of its flexibility to measure most material types: dielectrics, semiconductors, metals, superconductors, polymers, biological coatings, and even multilayers of these materials. Measurement of anisotropic materials has also made huge strides in recent years. Traditional SE measurements cover the ultraviolet, visible, and near infrared wavelengths. This spectral range is now acquired within seconds with high accuracy …
Optical Communications By Frequency Content Of Femtosecond Laser Pulses, Dennis Alexander, Mark L. Rohlfs
Optical Communications By Frequency Content Of Femtosecond Laser Pulses, Dennis Alexander, Mark L. Rohlfs
Department of Electrical and Computer Engineering: Faculty Publications
A free-space optical communications System is provided capable of transmitting data over long distances through the atmosphere. The communications System according to the present invention comprises an optical transmitter at a first location, the optical transmitter comprising a femtosecond pulsed laser Source for producing a train of femtosecond laser pulses. The optical transmitter further comprises a laser pulse width modulator to provide a pulse width modulated train of femtosecond laser pulses corresponding to the data being transmitted. The communications System further com prises an optical receiver at a Second location for receiving the modulated train of femtosecond laser pulses. The …
Mechanisms Of Photoluminescence From Silicon Nanocrystals Formed By Pulsed-Laser Deposition In Argon And Oxygen Ambient, X. Y. Chen, Yongfeng Lu, Y. H. Wu, B. J. Cho, M. H. Liu, D. Y. Dai, W. D. Song
Mechanisms Of Photoluminescence From Silicon Nanocrystals Formed By Pulsed-Laser Deposition In Argon And Oxygen Ambient, X. Y. Chen, Yongfeng Lu, Y. H. Wu, B. J. Cho, M. H. Liu, D. Y. Dai, W. D. Song
Department of Electrical and Computer Engineering: Faculty Publications
We have investigated the different mechanisms of photoluminescence (PL) of silicon nanocrystals due to the quantum confinement effect (QCE) and interface states. Si nanocrystals were formed by pulsed-laser deposition in inert argon and reactive oxygen gas. The collisions between the ejected species greatly influence the morphology of the Si nanocrystals and cause a transition from a film structure to a porous cauliflower-like structure, as the ambient gas pressure increases from 1 mTorr to 1 Torr. The oxygen content of the Si nanocrystals increases with increasing O2 ambient pressure, and nearly SiO2 stoichiometry is obtained when the O2 …
The Effect Of Plasma Shielding On Dust Particle Interaction In Low Pressure Plasmas, M. E. Marks, P. F. Williams
The Effect Of Plasma Shielding On Dust Particle Interaction In Low Pressure Plasmas, M. E. Marks, P. F. Williams
P. F. (Paul Frazer) Williams Publications
The interaction of charged dust particles in plasma is often modeled assuming a constant charge on each particle with the particle charge determined by requiring zero net current to the particles when they are far apart. In this paper the variation in particle charge is calculated for two-body encounters of dust particles taking into consideration mutual electrostatic shielding and a finite Debye length λD . Results are reported for particle radii between 0.0105λD and 0.349 λD. Work is also calculated as a function of particle separation, and it is shown that dust particle energies greater than …
United States Patent Application Publication: Divide And Conquer System And Method Of Dna Sequence Assembly, Khalid Sayood, Hasan H. Otu
United States Patent Application Publication: Divide And Conquer System And Method Of Dna Sequence Assembly, Khalid Sayood, Hasan H. Otu
Department of Electrical and Computer Engineering: Faculty Publications
The present invention provides a new algorithm for assembling fragments from a long DNA sequence. The algorithm of the invention Solves simultaneously fragment assembly-related problems. Such as the fragment orientation, overlap and layout phases. This is achieved by clustering fragments with respect to their Average Mutual Information (AMI) profiles using the k-means algorithm.
A Shape-Based Approach To Change Detection Of Lakes Using Time Series Remote Sensing Images, Jiang Li, Ram M. Narayanan
A Shape-Based Approach To Change Detection Of Lakes Using Time Series Remote Sensing Images, Jiang Li, Ram M. Narayanan
Department of Electrical and Computer Engineering: Faculty Publications
Shape analysis has not been considered in remote sensing as extensively as in other pattern recognition applications. However, shapes such as those of geometric patterns in agriculture and irregular boundaries of lakes can be extracted from the remotely sensed imagery even at relatively coarse spatial resolutions. This paper presents a procedure for efficiently retrieving and representing shapes of interesting features in remotely sensed imagery using supervised classification, object recognition, parametric contour tracing, and proposed piecewise linear polygonal approximation techniques. In addition, shape similarity can be measured by means of a computationally efficient metric. The study was conducted on a time …