Computer Sciences Commons^™

Theoretical Triple-Differential Cross Sections Of A Methane Molecule By A Proper-Average Method, Hari Chaluvadi, C. G. Ning, Don H. Madison

Physics Faculty Research & Creative Works

For the last few years, our group has calculated cross sections for electron-impact ionization of molecules using the molecular three-body distorted-wave approximation coupled with the orientation-averaged molecular orbital (OAMO) approximation. This approximation was very successful for calculating ionization cross sections for hydrogen molecules and to a lesser extent nitrogen molecules. Recently we used the approximation to calculate single ionization cross sections for the 1t₂ state of methane (CH₄) and we found major discrepancies with the experimental data. Here we investigate the validity of the OAMO approximation by calculating cross sections that have been properly averaged over all …

A Uniform Database Of Teleseismic Shear Wave Splitting Measurements For The Western And Central United States, Kelly H. Liu, Ahmed Elsheikh, Awas Lemnifi, Uranbaigal Purevsuren, Melissa Ray, Hesham Refayee, Bin B. Yang, Youqiang Yu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We present a shear wave splitting (SWS) database for the western and central United States as part of a lasting effort to build a uniform SWS database for the entire North America. The SWS measurements were obtained by minimizing the energy on the transverse component of the PKS, SKKS, and SKS phases. Each of the individual measurements was visually checked to ensure quality. This version of the database contains 16,105 pairs of splitting parameters. The data used to generate the parameters were recorded by 1774 digital broadband seismic stations over the period of 1989-2012, and represented all the available data …

New Pod Error Expressions, Error Bounds, And Asymptotic Results For Reduced Order Model Of Parabolic Pdes, John R. Singler

Mathematics and Statistics Faculty Research & Creative Works

The derivations of existing error bounds for reduced order models of time varying partialdi erential equations (PDEs) constructed using proper orthogonal decomposition (POD) haverelied on bounding the error between the POD data and various POD projections of that data.Furthermore, the asymptotic behavior of the model reduction error bounds depends on theasymptotic behavior of the POD data approximation error bounds. We consider time varyingdata taking values in two di erent Hilbert spacesHandV, withVH, and prove exactexpressions for the POD data approximation errors considering four di erent POD projectionsand the two di erent Hilbert space error norms. Furthermore, the exact error expressions …

Seismic Anisotropy And Subduction-Induced Mantle Fabrics Beneath The Arabian And Nubian Plates Adjacent To The Red Sea, Ahmed A. Elsheikh, Stephen S. Gao, Kelly H. Liu, Abdelnasser A. Mohamed, Youqiang Yu, Raafat E. Fat-Helbary

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

For most continental areas, the mechanisms leading to mantle fabrics responsible for the observed anisotropy remain ambiguous, partially due to the lack of sufficient spatial coverage of reliable seismological observations. Here we report the first joint analysis of shear-wave splitting measurements obtained at stations on the Arabian and Nubian Plates adjacent to the Red Sea. More than 1100 pairs of high-quality splitting parameters show dominantly N-S fast orientations at all 47 stations and larger-than-normal splitting times beneath the Afro-Arabian Dome (AAD). The uniformly N-S fast orientations and large splitting times up to 1.5 s are inconsistent with significant contributions from …

Service Discovery Protocols For Constrained Machine-To-Machine Communications, Berta Carballido Villaverde, Rodolfo De Paz Alberola, Antonio J. Jara, Szymon Fedor, Sajal K. Das

Computer Science Faculty Research & Creative Works

An emerging trend in many applications is to use resource-constrained wireless devices for machine-to-machine (M2M) communications. The observed proliferation of wireless embedded systems is expected to have a significant impact on future M2M applications if the services provided can be automatically discovered and accessed at runtime. In order to realize the decoupling of M2M applications and services, energy efficient service discovery mechanisms must be designed so as to minimize human intervention during configuration and management phases. However, many traditional service discovery protocols cannot be applied to wireless constrained devices because they introduce too much overhead, fail in a duty-cycled environment …

Computational Study Of The Rovibrational Spectrum Of Co₂-Cs₂, James Corgan Brown, Xiao-Gang Wang, Tucker Carrington Jr., Garry S. Grubbs, Richard Dawes

Chemistry Faculty Research & Creative Works

A new intermolecular potential energy surface, rovibrational transition frequencies, and line strengths are computed for CO₂-CS₂. the potential is made by fitting energies obtained from explicitly correlated coupled-cluster calculations using an interpolating moving least squares method. the rovibrational Schrödinger equation is solved with a symmetry-adapted Lanczos algorithm and an uncoupled product basis set. All four intermolecular coordinates are included in the calculation. in agreement with previous experiments, the global minimum of the potential energy surface (PES) is cross shaped. the PES also has slipped-parallel minima. Rovibrational wavefunctions are localized in the cross minima and the slipped-parallel …

Phonon Density Of States And Anharmonicity Of Uo₂, Judy W. Pang, Aleksandr V. Chernatynskiy, Bennett C. Larson, William J. Buyers, Douglas L. Abernathy, Kenneth J. Mcclellan, Simon R. Phillpot

Physics Faculty Research & Creative Works

Phonon density of states (PDOS) measurements have been performed on polycrystalline UO₂ at 295 and 1200 K using time-of-flight inelastic neutron scattering to investigate the impact of anharmonicity on the vibrational spectra and to benchmark ab initio PDOS simulations performed on this strongly correlated Mott insulator. Time-of-flight PDOS measurements include anharmonic linewidth broadening, inherently, and the factor of ~7 enhancement of the oxygen spectrum relative to the uranium component by the increased neutron sensitivity to the oxygen-dominated optical phonon modes. The first-principles simulations of quasiharmonic PDOS spectra were neutron weighted and anharmonicity was introduced in an approximate way by …

Seismic Anisotropy And Mantle Flow Beneath The Northern Great Plains Of North America, Bin B. Yang, Stephen S. Gao, Kelly H. Liu, Ahmed A. Elsheikh, Awad A. Lemnifi, Hesham A. Refayee, Youqiang Yu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A diverse set of tectonic features and the recent availability of high-quality broadband seismic data from the USArray and other stations on the northern Great Plains of North America provide a distinct opportunity to test different anisotropy-forming mechanisms. A total of 4138 pairs of well-defined splitting parameters observed at 445 stations show systematic spatial variations of anisotropic characteristics. Azimuthally invariant fast orientations subparallel to the absolute plate motion (APM) direction are observed at most of the stations on the Superior Craton and the southern Yavapai province, indicating that a single layer of anisotropy with a horizontal axis of symmetry is …

Receiver Function Constraints On Crustal Seismic Velocities And Partial Melting Beneath The Red Sea Rift And Adjacent Regions, Afar Depression, Cory A. Reed, Sattam Almadani, Stephen S. Gao, Ahmed A. Elsheikh, Solomon Cherie, Mohamed G. Abdel Salam, Allison K. Thurmond, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Afar Depression is an ideal locale for the investigation of crustal processes involved in the transition from continental rifting to oceanic spreading. To provide relatively high resolution images of the crust beneath the Red Sea rift (RSR) represented by the Tendaho graben in the Afar Depression, we deployed an array of 18 broadband seismic stations in 2010 and 2011. Stacking of about 2300 receiver functions from the 18 and several nearby stations along the ~200 km long array reveals an average crustal thickness of 22 ± 4 km, ranging from ~17 km near the RSR axis to 30 km …

Ensuring Energy Efficient Coverage For Participatory Sensing In Urban Streets, Adnan Khan, Sk Kajal Arefin Imon, Sajal K. Das

Computer Science Faculty Research & Creative Works

Participatory sensing is an approach to data collection for monitoring different scenarios with the help of smartphone sensors. As more and more sensors are being added to smartphones, monitoring a wide range of scenarios has become possible with participatory sensing. An important issue in such participatory sensing application is the coverage of the collected data that reflects how well the data samples represent the monitored area. In the traditional approach, the data collection process is assisted by a server that knows the location of the participating devices and selects the necessary ones to cover the monitored area efficiently. However, for …

Criticality And Quenched Disorder: Harris Criterion Versus Rare Regions, Thomas Vojta, José A. Hoyos

Physics Faculty Research & Creative Works

We employ scaling arguments and optimal fluctuation theory to establish a general relation between quantum Griffiths singularities and the Harris criterion for quantum phase transitions in disordered systems. If a clean critical point violates the Harris criterion, it is destabilized by weak disorder. At the same time, the Griffiths dynamical exponent z' diverges upon approaching the transition, suggesting unconventional critical behavior. In contrast, if the Harris criterion is fulfilled, power-law Griffiths singularities can coexist with clean critical behavior, but z' saturates at a finite value. We present applications of our theory to a variety of systems including quantum spin chains, …

Role Of Electron Saddle Swaps In The Photon Spectra Following Li³⁺ Charge-Exchange Collisions With H*(N = 2), Na(3s), Na*(3p), And Li(2s) Targets, Sebastian Otranto, R. Hoekstra, Ronald E. Olson

Physics Faculty Research & Creative Works

The role of electron saddle swaps in collisions of bare Li with metastable hydrogen and alkali-metal atoms is investigated by means of the classical trajectory Monte Carlo method. In particular, we show that oscillations as a function of collision energy in the photon spectra resulting from charge exchange are directly related to the number of potential-saddle crossings that a receding electron can achieve during a given reaction. The range of impact energies spanned is 0.01-50 keV/amu, an area of interest for diagnostic purposes in tokamak nuclear fusion power reactors.

Model-Free Q-Learning Over Finite Horizon For Uncertain Linear Continuous-Time Systems, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel optimal control over finite horizon has been introduced for linear continuous-time systems by using adaptive dynamic programming (ADP). First, a new time-varying Q-function parameterization and its estimator are introduced. Subsequently, Q-function estimator is tuned online by using both Bellman equation in integral form and terminal cost. Eventually, near optimal control gain is obtained by using the Q-function estimator. All the closed-loop signals are shown to be bounded by using Lyapunov stability analysis where bounds are functions of initial conditions and final time while the estimated control signal converges close to the optimal value. The simulation …

Event-Based Optimal Regulator Design For Nonlinear Networked Control Systems, Avimanyu Sahoo, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel stochastic event-based near optimal control strategy to regulate a networked control system (NCS) represented as an uncertain nonlinear continuous time system. An online stochastic actor-critic neural network (NN) based approach is utilized to achieve the near optimal regulation in the presence of network constraints, such as, network induced time-varying delays and random packet losses under event-based transmission of the feedback signals. The transformed nonlinear NCS in discrete-time after the incorporation the delays and packet losses are utilized for the actor-critic NN based controller design. To relax the knowledge of the control coefficient matrix, a NN …

Neural Network-Based Adaptive Optimal Consensus Control Of Leaderless Networked Mobile Robots, Haci Mehmet Guzey, Hao Xu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel neural network (NN)-based optimal adaptive consensus control scheme is introduced in this paper for networked mobile robots in the presence of unknown robot dynamics. Throughout the paper, two NNs are used. The unknown formation dynamics of each robot is identified by using the first NN. The second NN is utilized to approximate a novel value function derived in this paper as a function of augmented error vector, which is comprised of the regulation and consensus-based formation errors of each robot. A novel near optimal controller is developed by using approximated value function and identified formation dynamics. The Lyapunov …

Mapreduce-Based Restmd: Enabling Large-Scale Sampling Tasks With Distributed Hpc Systems, Praveenkumar Kondikoppa, Richard Platania, Seung Jong Park, Tom Keyes, Jaegil Kim, Nayong Kim, Joohyun Kim, Shuju Bai

Computer Science Faculty Research & Creative Works

A novel implementation of Replica Exchange Statistical Temperature Molecular Dynamics (RESTMD), belonging to a generalized ensemble method and also known as parallel tempering, is presented. Our implementation employs the MapReduce (MR)-based iterative framework for launching RESTMD over high performance computing (HPC) clusters including our test bed system, Cyber-infrastructure for Reconfigurable Optical Networks (CRON) simulating a network-connected distributed system. Our main contribution is a new implementation of STMD plugged into the well-known CHARMM molecular dynamics package as well as the RESTMD implementation powered by the Hadoop that scales out in a cluster and across distributed systems effectively. To address challenges for …

Wireless Ad Hoc Networks Connectivity Assessment And Relay Node Deployment, Maggie Xiaoyan Cheng, Yi Ling, Brian M. Sadler

Computer Science Faculty Research & Creative Works

We consider the network connectivity problem in a wireless ad hoc network. Network connectivity is measured by the conductance of the network, also called the Cheeger constant of the graph. A partition algorithm based on this measure is developed that divides the network at the bottleneck area. After the network is bisected, a relay node may be deployed between the two parts to increase the conductance of the network. The relay node deployment problem is formulated as an integer linear program to maximize the number of connections between the nodes on the two sides of the cut, and then a …

Smart And Cooperative Sensor Networks, Hongke Zhang, Sy Yen Kuo, Sajal K. Das, Mikael Gidlund

Computer Science Faculty Research & Creative Works

No abstract provided.

An Access Point To Device Association Technique For Optimized Data Transfer In Mobile Grids, Ansuman Banerjee, Himadri Sekhar Paul, Arijit Mukherjee, Pubali Datta, Sajal K. Das

Computer Science Faculty Research & Creative Works

In a mobile grid computing framework where mobile devices are used as computing resources, minimizing the task offloading time remains an important issue. A task is an independent unit of execution consisting of a input data volume for execution and optionally a target-specific executable. We consider a mobile grid infrastructure where mobile devices are connected via Wi-Fi network and the grid infrastructure has a set of tasks (i.e. a set of data volumes) to be transferred to a subset of the mobile devices. In a Wi-Fi network, mobile devices usually associate themselves to the access points (APs) having the strongest …

Mapreduce Based Parallel Suffix Tree Construction For Human Genome, Umesh Chandra Satish, Praveenkumar Kondikoppa, Seung Jong Park, Manish Patil, Rahul Shah

Computer Science Faculty Research & Creative Works

Genome indexing is the basis for many bioinformatics applications. Read mapping (sequence alignment) is one such application where the goal is to align millions of short reads against reference genome. Several tools are available for read mapping which rely on different indexing techniques to expedite the alignment process. However, many of these contemporary alignment programs are sequential, memory intensive and cannot be easily scaled for larger genomes. Suffix tree is one of the most widely used data structures for indexing strings (genomes). Building a scalable suffix-tree based tool is particularly challenging due to the difficulties involved in parallel construction of …

Secure K-Nearest Neighbor Query Over Encrypted Data In Outsourced Environments, Yousef Elmehdwi, Bharath K. Samanthula, Wei Jiang

Computer Science Faculty Research & Creative Works

For the past decade, query processing on relational data has been studied extensively, and many theoretical and practical solutions to query processing have been proposed under various scenarios. With the recent popularity of cloud computing, users now have the opportunity to outsource their data as well as the data management tasks to the cloud. However, due to the rise of various privacy issues, sensitive data (e.g., medical records) need to be encrypted before outsourcing to the cloud. In addition, query processing tasks should be handled by the cloud; otherwise, there would be no point to outsource the data at the …

Intelligent Management Systems For Energy Efficiency In Buildings: A Survey, Alessandra De Paola, Marco Ortolani, Giuseppe Lo Re, Giuseppe Anastasi, Sajal K. Das

Computer Science Faculty Research & Creative Works

In recent years, reduction of energy consumption in buildings has increasingly gained interest among researchers mainly due to practical reasons, such as economic advantages and long-term environmental sustainability. Many solutions have been proposed in the literature to address this important issue from complementary perspectives, which are often hard to capture in a comprehensive manner. This survey article aims at providing a structured and unifying treatment of the existing literature on intelligent energy management systems in buildings, with a distinct focus on available architectures and methodology supporting a vision transcending the well-established smart home vision, in favor of the novel Ambient …

Content Distribution In Delay-Tolerant Networks Using Social Context, Roy Cabaniss, Sanjay Madria

Computer Science Faculty Research & Creative Works

Wireless communication technologies have given rise to the development of Delay Tolerant Networks, a collection of devices that route data opportunistically. These networks can be used to distribute data, such as news articles, advertisements, and media, to interested clients. To deliver content efficiently, the Social Content Distribution (SCD) schema collects social context data and request patterns. Nodes then are designated as mobile repositories, or throw boxes, which house large content stores. Clients request specific articles from nearby repositories. Which nodes will request data can be predicted based on request and social patterns, so the SCD schema can fulfill content requests …

Sensor Authentication In Collaborating Sensor Networks, Jake Bielefeldt, Sriram Chellappan

Computer Science Faculty Research & Creative Works

In this paper, we address a new security problem in the realm of collaborating sensor networks. By collaborating sensor networks, we refer to the networks of sensor networks collaborating on a mission, with each sensor network is independently owned and operated by separate entities. Such networks are practical where a number of independent entities can deploy their own sensor networks in multi-national, commercial, and environmental scenarios, and some of these networks will integrate complementary functionalities for a mission. In the scenario, we address an authentication problem wherein the goal is for the Operator Oi of Sensor Network Si to correctly …

Qos Aware Geographic Opportunistic Routing In Wireless Sensor Networks, Long Cheng, Jianwei Niu, Jiannong Cao, Sajal K. Das, Yu Gu

Computer Science Faculty Research & Creative Works

QoS routing is an important research issue in wireless sensor networks (WSNs), especially for mission-critical monitoring and surveillance systems which requires timely and reliable data delivery. Existing work exploits multipath routing to guarantee both reliability and delay QoS constraints in WSNs. However, the multipath routing approach suffers from a significant energy cost. In this work, we exploit the geographic opportunistic routing (GOR) for QoS provisioning with both end-to-end reliability and delay constraints in WSNs. Existing GOR protocols are not efficient for QoS provisioning in WSNs, in terms of the energy efficiency and computation delay at each hop. To improve the …

Concurrent Transmission Scheduling For Wpans With Adaptive Data Rate, Maggie X. Cheng, Quanmin Ye, Lin Cai

Computer Science Faculty Research & Creative Works

We consider the maximum throughput scheduling problem in a millimeter-wave wireless personal area network in which users can use adaptive modulation and coding schemes to change their data rates. The scheduling problem is to map transmissions to time slots so that the total throughput is maximized. Due to the ultra-wide bandwidth of the mm Wave band, bad scheduling tends to waste significant channel resource. It is worth the effort to consider a more sophisticated scheduling scheme than the simple serial TDMA scheme. The challenge is that the achieved data rate of one flow is limited by the interference from other …

Sensor Cloud: A Cloud Of Virtual Sensors, Sanjay Madria, Vimal Kumar, Rashmi Dalvi

Computer Science Faculty Research & Creative Works

Newer models for interacting with wireless sensors such as Internet of Things and Sensor Cloud aim to overcome restricted resources and efficiency. The Missouri S&T (science and technology) sensor cloud enables different networks, spread in a huge geographical area, to connect together and be employed simultaneously by multiple users on demand. Virtual sensors, which are at the core of this sensor cloud architecture, assist in creating a multiuser environment on top of resource-constrained physical wireless sensors and can help in supporting multiple applications. © 1984-2012 IEEE.

Privacy And Trustworthiness Management In Moving Object Environments, Sashi Gurung

Doctoral Dissertations

"The use of location-based services (LBS) (e.g., Intel's Thing Finder) is expanding. Besides the traditional centralized location-based services, distributed ones are also emerging due to the development of Vehicular Ad-hoc Networks (VANETs), a dynamic network which allows vehicles to communicate with one another. Due to the nature of the need of tracking users' locations, LBS have raised increasing concerns on users' location privacy. Although many research has been carried out for users to submit their locations anonymously, the collected anonymous location data may still be mapped to individuals when the adversary has related background knowledge.

To improve location privacy, in …

Access Control Delegation In The Clouds, Pavani Gorantla

Masters Theses

"Current market trends need solutions/products to be developed at high speed. To meet those requirements sometimes it requires collaboration between the organizations. Modern workforce is increasingly distributed, mobile and virtual which will incur hurdles for communication and effective collaboration within organizations. One of the greatest benefits of cloud computing has to do with improvements to organizations communication and collaboration, both internally and externally. Because of the efficient services that are being offered by the cloud service providers today, many business organizations started taking advantage of cloud services. Specifically, Cloud computing enables a new form of service in that a service …

Evolving Decision Trees For The Categorization Of Software, Jasenko Hosic

Masters Theses

"Current manual techniques of static reverse engineering are inefficient at providing semantic program understanding. An automated method to categorize applications was developed in order to quickly determine pertinent characteristics. Prior work in this area has had some success, but a major strength of the approach detailed in this thesis is that it produces heuristics that can be reused for quick analysis of new data. The method relies on a genetic programming algorithm to evolve decision trees which can be used to categorize software. The terminals, or leaf nodes, within the trees each contain values based on selected features from one …