Computer Engineering Commons^™

Quantitative Analysis Of Propagation Characteristics For Mobile Wimax, Pradhumna Shrestha, Puttipong Mahasukhon, Michael Hempel, Tao Ma, Hamid Sharif

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

In wireless networks, careful planning and link budget analysis is required for delivering maximum throughput reliably with minimum overhead. The efficiency of planning and eventual network performance is totally dependent upon the accuracy and quality of data used for analysis. In most studies, computer simulations and analytical models are used for generating such data. However these simulations are limited to many assumptions which are different from the actual implemented hardware, therefore, the data generated are not accurate. In this paper, we analyze the performance of Mobile WiMAX utilizing the empirical data measured from leading WiMAX equipment. We believe this data …

A Study On Energy Efficient Multi-Tier Multi-Hop Wireless Sensor Networks For Freight-Train Monitoring, Puttipong Mahasukhon, Hamid Sharif, Michael Hempel, Ting Zhou, Tao Ma, Pradhumna Shrestha

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

The North American freight railroad industry is trying to leverage wireless sensor networks (WSN) onboard railcars for advanced monitoring and alerting. In railroad environments, freight train WSNs exhibit a linear chain-like topology of significant length. Thus, existing wireless technologies such as the IEEE 802.15.4 communication protocol, based on a star topology, are unable to provide reliable service. The end-to-end communication between nodes generally relies on individual nodes communicating with their respective neighbors to carry the information over multiple hops and deliver it to the preferred destination. The routing performance and reliability significantly degrades with increasing number of hops. We proposed …

A High-Quality Mach-Zehnder Interferometer Fiber Sensor By Femtosecond Laser One-Step Processing, Longjiang Zhao, Lan Jiang, Sumei Wang, Hai Xiao, Yongfeng Lu, Hai-Lung Tsai

Department of Electrical and Computer Engineering: Faculty Publications

During new fiber sensor development experiments, an easy-to-fabricate simple sensing structure with a trench and partially ablated fiber core is fabricated by using an 800 nm 35 fs 1 kHz laser. It is demonstrated that the structure forms a Mach-Zehnder interferometer (MZI) with the interference between the laser light passing through the air in the trench cavity and that in the remained fiber core. The fringe visibilities are all more than 25 dB. The transmission spectra vary with the femtosecond (fs) laser ablation scanning cycle. The free spectral range (FSR) decreases as the trench length increases. The MZI structure is …

A Web Application For Financial Trading Simulation, Li-Chiou Chen, Lixin Tao, Padma Kadiyala

Cornerstone 3 Reports : Interdisciplinary Informatics

No abstract provided.

Pwisegen: Generating Test Cases For Pairwise Testing Using Genetic Algorithms, Pedro Flores, Yoonsik Cheon

Departmental Technical Reports (CS)

Pairwise testing is a combinatorial testing technique that tests all possible pairs of input values. Although, finding a smallest set of test cases for pairwise testing is NP-complete, pairwise testing is regarded as a reasonable cost-benefit compromise among combinatorial testing methods. In this paper we formulate the problem of finding a pairwise test set as a search problem and apply a genetic algorithm to solve it. We also describe an open-source tool called PWiseGen for generating pairwise test sets. According to our experiments, PWiseGen produces competitive results compared with existing pairwise testing tools. Besides, it provides a framework and a …

Towards Optimal Few-Parametric Representation Of Spatial Variation: Geometric Approach And Environmental Applications, Misha Kosheleva, Octavio Lerma, Craig Tweedie

Departmental Technical Reports (CS)

In this paper, we use geometric approach to showthat under reasonable assumption, the spatialvariability of a field f(x), i.e., the expectedvalue F(z)=E[(f(x+z)-f(x))²], has the formF(z)=|Σ g_ij*z_i*z_j|^α.We explain how to find g_ij and αfrom the observations, and how to optimally place sensorsin view of this spatial variability.

Measures Of Deviation (And Dependence) For Heavy-Tailed Distributions And Heir Estimation Under Interval And Fuzzy Uncertainty, Nitaya Buntao, Vladik Kreinovich

Departmental Technical Reports (CS)

Traditionally, in science and engineering, most statistical techniques are based on the assumption that the random variables are normally distributed. For such distributions, a natural characteristic of the "average" value is the mean, and a natural characteristic of the deviation from the average is the variance. However, in many practical situations, e.g., in economics and finance, we encounter probability distributions for which the variance is infinite; such distributions are called heavy-tailed. For such distributions, we describe which characteristics can be used to describe the average and the deviation from the average, and how to estimate these characteristics under interval …

Qos-Aware Fine-Grained Power Management In Networked Computing Systems, Jiayu Gong

Wayne State University Dissertations

Power is a major design concern of today's networked computing systems, from low-power battery-powered mobile and embedded systems to high-power enterprise servers. Embedded systems are required to be power efficiency because most embedded systems are powered by battery with limited capacity. Similar concern of power expenditure rises as well in enterprise server environments due to cooling requirement, power delivery limit, electricity costs as well as environment pollutions.

The power consumption in networked computing systems includes that on circuit board and that for communication. In the context of networked real-time systems, the power dissipation on wireless communication is more significant than …

Autonomous Mobility And Manipulation Of A 9-Dof Wmra, William Garrett Pence

USF Tampa Graduate Theses and Dissertations

The wheelchair-mounted robotic arm (WMRA) is a 9-degree of freedom (DoF) assistive system that consists of a 2-DoF modified commercial power wheelchair and a custom 7-DoF robotic arm. Kinematics and control methodology for the 9-DoF system that combine mobility and manipulation have been previously developed and implemented. This combined control allows the wheelchair and robotic arm to follow a single trajectory based on weighted optimizations. However, for the execution of activities of daily living (ADL) in the real-world environment, modified control techniques have been implemented.

In order to execute macro ADL tasks, such as a "go to and pick up" …

A Dynamic Hierarchical Web-Based Portal, Matthew James Spaulding

USF Tampa Graduate Theses and Dissertations

A dynamic hierarchical web-based portal was created to house a suite of web-based supply chain management applications. The portal was designed in a hierarchical manner to match the structure of large companies. Administrators of the the portal have the ability to form the portal in such a way to mimic the existing structure of their company. Access rights to the applications in the portal may be granted or denied per division and the users of the portal are placed in these divisions based on their duty in the company. In addition, users are granted roles which dictate their ability to …

Dynamic Video Object Detection With Single Ptu Camera, Yun Ye, Song Ci, Yanwei Liu, Hui Tang

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

This paper presents a video object detection method under dynamic background with single PTU (pantilt unit) camera. The overall procedure contains two steps. First the moving object is tracked through interactive Mean Shift estimation and PTU control. Camera angular speed is updated online according to the estimated object position, whereby the object can remain in the center area of the image plane. In the second step, the foreground is detected through background subtraction and shape contour. An adaptive correlation thresholding method is applied to mitigate the detection distortion in boundary areas. Variational level set contour is then applied to further …

Sub Pixel Analysis And Processing Of Sensor Data For Mobile Target Intelligence Information And Verification, Theresa Allen Williams

Doctoral Dissertations

This dissertation introduces a novel process to study and analyze sensor data in order to obtain information pertaining to mobile targets at the sub-pixel level. The process design is modular in nature and utilizes a set of algorithmic tools for change detection, target extraction and analysis, super-pixel processing and target refinement. The scope of this investigation is confined to a staring sensor that records data of sub-pixel vehicles traveling horizontally across the ground. Statistical models of the targets and background are developed with noise and jitter effects. Threshold Change Detection, Duration Change Detection and Fast Adaptive Power Iteration (FAPI) Detection …

The Forest Overlay Network, Logan Stafman

All Computer Science and Engineering Research

Forest is an overlay network designed for large real-time distributed systems. In particular, we’re interested in virtual worlds that provide high-quality interaction over a constantly changing pattern of communication. Forest is suitable for applications in which many entities send data to a large set of constantly changing entities. By using tree-structured channels, we can create logically isolated private networks which support both unicast and multicast routing. In this paper, we will discuss the core components of Forest and measure the performance of the control elements of the network. We will also provide examples of control sequences and the roles played …

Feedback Thermal Control Of Real-Time Systems On Multicore Processors, Yong Fu, Nicholas Kottenstette, Chenyang Lu, Xenofon D. Koutsoukos

All Computer Science and Engineering Research

Real-time systems face significant challenges in thermal management with their adoption of modern multicore processors. While earlier research on feedback thermal control has shown promise in dealing with the uncertainties in the thermal characteristics, multicore processors introduce new challenges that cannot be handled by previous solutions designed for single-core processors. Multicore processors require the temperatures and real-time performance of multiple cores to be controlled simultaneously, leading to multi-input-multi-output (MIMO) control problems with inter-core thermal coupling. Furthermore, current Dynamic Voltage and Frequency Scaling (DVFS) mechanisms only support a finite set of states, leading to discrete control variables that cannot be handled …

Multi-Core Real-Time Scheduling For Generalized Parallel Task Models, Abusayeed Saifullah, Kunal Agrawal, Chenyang Lu, Christopher Gill

All Computer Science and Engineering Research

Multi-core processors over a significant performance increase over single-core processors. Therefore, they have the potential to enable computation-intensive real-time applications with stringent timing constraints that cannot be met on traditional single-core processors. However, most results in traditional multiprocessor real-time scheduling are limited to sequential programming models and ignore intra-task parallelism. In this paper, we address the problem of scheduling periodic parallel tasks with implicit deadlines on multi-core processors. We first consider a synchronous task model where each task consists of segments, each segment having an arbitrary number of parallel threads that synchronize at the end of the segment. We propose …

Results Of An Observational Study On Sketching, Cindy Grimm

All Computer Science and Engineering Research

We present the results of an observational study on sketching. Artists were asked to sketch a small number of objects and comment on how and why they made the marks they did. We summarize these findings, from low-level details on individual marks through the drawing construction order. Based on these observations we provide suggestions for future research directions in 3D sketching.

Flux Balance Analysis Of Dynamic Metabolism In Shewanella Oneidensis Mr-1 Using A Static Optimization Approach, Xueyang Feng, You Xu, Yixin Chen, Yinjie Tang

All Computer Science and Engineering Research

Shewanella bacteria are facultative anaerobes isolated from aquatic and sedimentary environments (Hau and Gralnick 2007) with a broad capacity for reduction of multiple electron receptors (Pinchuk et al. 2009; Serres and Riley 2006), including Fe(III), Mn(IV), sulfur, nitrate, and fumarate. With the accomplishment of complete genome sequencing of several Shewanella bacteria, the general pictures of the carbon metabolism have been revealed (Serres and Riley 2006). metabolism. One of the most physiological methods to decipher the time-variant metabolic regulation is to determine the dynamic distribution of intracellular metabolic fluxes since it reveals the final response of cellular metabolism to genomic, transcriptional …

Energy-Efficient Low Power Listening For Wireless Sensor Networks In Noisy Environments, Mo Sha, Gregory Hackmann, Chenyang Lu

All Computer Science and Engineering Research

Low Power Listening (LPL) is a common MAC-layer technique for reducing energy consumption in wireless sensor networks, where nodes periodically wake up to sample the wireless channel to detect activity. However, LPL is highly susceptible to false wakeups caused by environmental noise being detected as activity on the channel, causing nodes to spuriously wake up in order to receive nonexistent transmissions. In empirical studies in residential environments, we observe that the false wakeup problem can significantly increase a node's duty cycle, compromising the benefit of LPL. We also find that the energy-level threshold used by the Clear Channel Assessment (CCA) …

Hierarchical Scheduling For Multicores With Multilevel Cache Hierarchies, Kunal Agrawal, Jim Sukha

All Computer Science and Engineering Research

Cache-locality is an important consideration for the performance in multicore systems. In modern and future multicore systems with multilevel cache hierarchies, caches may be arranged in a tree of caches, where a level k cache is shared between Pk processors, called a processor group, and Pk increases with k. In order to get good performance, as much as possible, subcomputations that share more data should execute on processors which share a lower-level cache. Therefore, the number of cache misses in these systems depends on the scheduling decisions, and a scheduler is responsible for not just achieving good load-balance and low …

Optimization Of Gene Prediction Via More Accurate Phylogenetic Substitution Models, Ezekiel Maier, Randall H. Brown, Michael R. Brent

All Computer Science and Engineering Research

Determining the beginning and end positions of each exon in each protein coding gene within a genome can be difficult because the DNA patterns that signal a gene’s presence have multiple weakly related alternate forms and the DNA fragments that comprise a gene are generally small in comparison to the size of the genome. In response to this challenge, automated gene predictors were created to generate putative gene structures. N SCAN identifies gene structures in a target DNA sequence and can use conservation patterns learned from alignments between a target and one or more informant DNA sequences. N SCAN uses …