Master's Theses (2009 -)

Hybrid Coupler Implemented as a Phase Shifter

John P. Vitale — Wed, 20 Feb 2013 11:26:47 PST

Phase shifters are two-port microwave devices which take an input signal and output a phase shifted version of the signal. These devices can be used in phased antenna arrays, frequency translators, and IQ modulator/demodulator systems. The goal for this work is to construct a hybrid coupler phase shifter which will provide a 90 degree phase shift to a signal with a center frequency of 1800 MHz over a 5% bandwidth. This work is novel because the hybrid coupler phase shifter has not been extensively studied. Some papers have provided rough guidelines for constructing these shifters, but there is little exploration of performance. This work uses RF Sim as a simulation tool to provide design analysis, and experimental work was performed in the RF laboratory at the Marquette University College of Engineering. The basis for the design of the phase shifter comes from idealized design guidelines found in white papers. Realistic effects inherent in the design are shown in the final results. Updated simulation results are provided which provide compensation for these effects to achieve the desired performance.

Simulator Centered Design: Abstracting the Operating Environment on Radio Controlled Airplane Autopilot Development

David A. VanKampen — Wed, 20 Feb 2013 11:21:13 PST

Software development for applications used in high-risk and high-reliability environments is a difficult task. Testing in areas where failure could mean loss of equipment or damage to the environment becomes an implausible option. Testing in a simulated environment presents itself as a viable solution to this problem. One issue found when using simulators is they often have complex communication interfaces. After the simulator is no longer needed, the time spent developing the interface is lost. Simulator Centered Design addresses this by re-using simulator interfaces to make the real environment appear the same to the application as the simulator makes the environment appear. This thesis tests this theory by supplying an interface platform for a radio controlled airplane based around the X-Plane simulator interface.

Quantitative Analysis of Methangenic Community in Anaerobic Digesters and its Response to Freeze Drying and Exposure to Oxygen

Keerthi Cherukuri — Wed, 20 Feb 2013 11:18:16 PST

Methanogens are integral to carbon cycling, catalyzing the production of methane and carbon dioxide, both potent greenhouse gases. Methane is produced in a wide variety of highly reduced anaerobic environments, as well as by degradation of organic compounds in industrial and municipal wastewater. This process is carried out by the concerted activity of an interdependent microbial community, composed of Bacteria and Archaea, the later including methanogens which complete the final step and produce methane and carbon dioxide. Methanogenesis is often the rate limiting step and is sensitive to processing imbalances. Therefore, an understanding of the microbial community structure and dynamics in anaerobic process is a basic requirement to optimize anaerobic digestion for increased renewable energy production. To examine the relationship between methane production and methanogen community structure, quantitative polymerase chain reaction (qPCR) was used to quantify the total methanogen community (mcrA gene) as well as specific genera (16S rRNA gene) in biomass from industrial scale digesters. Results from this study revealed that there was a positive correlation between methane production and mcrA and Methanospirillum transcripts. It was also found that reactors not dominated by any particular genus, but those that had a balanced community of hydrogenotrophic and aceticlastic methanogens had a higher capacity to resist organic overload and produce methane. One of the major problems faced in anaerobic digestion process is its inherent instability and sensitivity to frequent exposure to oxygen. qPCR analyses of 16S rRNA revealed that Methanoculleus had significantly lower activity, while Methanospirillum and Methanosaeta had significantly higher activity at higher oxygen concentrations. Finally, this study also presents the use of freeze drying as a viable method for preserving anaerobic methanogenic biomass. qPCR with 16S rRNA genus specific primers revealed that methanogens varied in their ability to tolerate the process of freeze drying. Methanospirillum had the highest 16S rRNA transcripts before and after drying, followed by Methanosaeta and Methanoculleus. Therefore, the data obtained from this study helps to determine the identity of desirable organisms and community architecture in relation to digester performance, exposure to oxygen and low temperature desiccation encountered during preservation by freeze drying.

Real Time Control Framework Using Android

Aaron Pittenger — Wed, 20 Feb 2013 11:12:13 PST

One potential application for a smartphone-type device is a flight management and control computer for an unmanned aerial vehicle (UAV). The hardware employed in most smartphones and tablets has the capabilities necessary to fly an air vehicle without user interaction. The user can pre-program in a flight plan and the smartphone will do the rest. In the past, this real time control application has been done using many separate sensor packages and processors, but never on a single, stand-alone device. Also, capabilities such as the high definition camera present on most smartphones can take photographs and store them on the phone for retrieval later. This opens many potential markets for a device of this nature. Farmers that have large properties could use this to see if their fences are broken. The general public could use the application to take aerial views of their properties. Law enforcement could be an application for this project; to map out house fires or other potentially harmful situations before lives are put at stake. The real challenge with using a smartphone as a flight management and control computer is the real time control of the aircraft. In order to accomplish real time control, the computer must have the sensors necessary for real-time control, a fast processor, capable of running a periodic process at frequencies greater than 10Hz (the faster the better) and the ability to read the sensor input and act on it during the time slice given for that process. With a multi-threaded, embedded, real-time operating system, this typically is not a problem (given a fast enough processor and enough inputs for all the sensor data). Doing the same type of calculations and control on a consumer product made to run many applications at the same time is difficult. This thesis will demonstrate how a real time control process was implemented on an Android phone.

Three-Dimensional Biomechanical Model of Wrist Dynamics during Tasks of Daily Living

Patrick Roscher — Wed, 20 Feb 2013 11:09:12 PST

An understanding of wrist dynamics during functional movements is required to better diagnose and treat wrist injury and disease. Currently, there is a lack of upper extremity (UE) models that combine both the motions and resulting forces that occur in the wrist during daily activities. The purpose of this study is to create a three-dimensional (3D) model of the upper extremity that describes kinematics and wrist kinetics during functional activities. A model of this type could benefit clinical diagnosis, treatment, and follow-up care of orthopaedic and neurological disorders of the wrist. The created dynamic wrist model was used to test ten normal subjects during seven tasks (flexion/extension, radial/ulnar deviation, pronation/supination, hammering, jar opening, door-opening, and isometric pushing). Primary and secondary wrist motions were described for each task, as well as tri-axial forces and moments at the wrist for jar opening, door-opening, and isometric push tasks. These data were stratified by gender to demonstrate the model’s capacity to compare populations. Data were analyzed and showed that there were very few significant differences between male and female populations. This model demonstrates potential for clinical use for pre- and post-treatment assessment and initial wrist function baseline assessment.

Powered Transtibial Prosthetic Device Control System Design, Implementation and Testing

Jinming Sun — Wed, 20 Feb 2013 10:49:48 PST

A powered lower limb prosthesis, which consists of a four bar mechanism, a torsional spring and a brushed DC motor, was previously designed and fabricated. To regulate the motor power input, a two level controller was proposed and built. The control algorithm includes a higher level finite state controller and lower level PID controllers. To implement the control system, a digital signal processor (DSP) control board and MATLAB Simulink were used to realize the higher level control and a DC motor controller was used to realize the lower level PID control. Sensors were selected to provide the required feedback. The entire control system was implemented on a convenient to carry backpack. Amputee subject testing was performed to obtain some experimental verification of the design. The results showed that the control system performed consistently with the designed control algorithm and did assist in the amputee’s walking. Compared to a currently available powered prosthesis, this control is simple in structure and able to mimic the nonlinear behavior of the ankle closely.

Manna from the Glossy Pulpit: Food Advertising in Women's Magazines

Kira-Lynn Reeves — Wed, 20 Feb 2013 10:45:07 PST

Women’s magazines reach millions of readers each month, and have been the subject of many academic inquires from media effects studies to feminist analyses. While many studies have investigated female readers’ experience with these texts, or examined the advertising content of women’s magazines, little research to date has focused on food advertising. This liberal feminist critique explores the experience of reading the 2011 issues of the three popular women’s magazines, Glamour, SELF, and Family Circle. Using Stern’s (1996) textual analysis method for advertisements, this study examines how food advertisements in women’s magazines encourage women to think about food and eating. Food advertisements tend to align with the overall narrative constructed by the magazine in which they appear: food is accessorized in Glamour advertisements as a means for enhancing one’s life; in SELF, food is presented as both fuel and reward for exercising; and in Family Circle, food represents a mother’s love and a woman’s realm as the family’s grocery shopper, meal planner, and primary cook. Food takes on multiple meanings through advertising and frequently suggests that a woman’s food choices are indicative of her worth, personality, or success as a mother, for example. Possible interpretations and implications of these food advertising observations are explored.

Investigating a Horizontal Helical Antenna for use in the Phantom Monopole Configuration

Mattison LeMieux — Wed, 20 Feb 2013 10:39:41 PST

Recently, the phantom monopole configuration was successfully simulated using wire loop antennas. The wire loop antennas have an undesirable input impedance, making them difficult to match and implement. A new type of antenna that has a more desirable impedance while still maintaining the same near magnetic field and far field radiation pattern is investigated in this work. The research done focuses on a horizontally placed helical antenna. There is little research done on a horizontally placed helical antenna so several different parameters of this antenna were investigated. A normal mode helical antenna was chosen because of its size and impedance. A helical antenna is an electrically small antenna, like the wire loop antenna, with an improved impedance compared to the wire loop. The work done included computer simulation and physical construction of the helical antenna. The physical testing was done in order to support and verify the computer modeling of the phantom monopole. Through testing and simulation, it is shown here that a horizontally placed helical antenna provides an alternative to the wire loop antenna originally investigated. By placing the helical antenna horizontally, the near magnetic field and far field radiation pattern mimic the original wire loop configuration. The phantom monopole is recreated using a new type of antenna that has an improved input impedance.

Repair and Strengthening of Bridge Substructures

Steven W. Ainge — Wed, 20 Feb 2013 10:35:59 PST

Deterioration of bridge substructures has been a serious concern throughout Wisconsin. Concrete, steel and timber members all require distinct repair methods which not only address the true causes of deterioration, but protect the member from future damage. Utilizing repair techniques that merely address the effect of the deterioration has proven costly and unreliable. Understanding the relationship between cost and service life of modern repair methods can help maintenance engineers make informed decisions that will maximize efficacy. A survey was sent to 90 maintenance engineers throughout the United States to determine the efficacy and cost of common repair methods. Unique repair procedures were also investigated based on the results of the survey. Eight bridges throughout the Southeast and Southwest regions of WisDOT were documented. These bridges displayed varying stages of deterioration as well as typical repair methods. By evaluating these bridges it was determined that the damage caused by deicing chemicals is extensive and varying. Expansion joint degradation has accounted for a large portion of deterioration throughout Wisconsin’s bridge infrastructure. Documentation indicating how long repairs had been in place gave the research team an estimate for longevity of repairs in Wisconsin. Repair methods were documented and analyzed for concrete, timber, steel and scour. They were considered for their longevity, relevance in Wisconsin’s climate, ease of completion and cost. Further organization highlighted repairs based on specific substructure element relevance, in an attempt to address unique deterioration by substructure member. After the repairs were analyzed, three separate decision matrices were created in order to compare differing repair methods. Decision matrices were created for concrete repairs, pile repairs and scour repairs. The pile repair decision matrix was created in lieu of separate timber and steel decision matrices, since those materials are typically only used for piles of modern substructures. These decision matrices can be used to design appropriate substructure repairs which will be both cost-effective and durable.

Electroluminescence from ZnO Nanostructure Synthesizes between Nanogap

Cheng Jiang — Wed, 20 Feb 2013 10:12:18 PST

This thesis presents the investigation of a nanoscale light-emitting diode (LED) device. The nanoscale LED has a great potential to be used as a light source for biomedical screening and fluorescence lifetime spectroscopy. It can also be developed to a single photon emitter for the application of quantum computing. The nano-LED has the electrical structure of a metal-semiconductor-metal (MSM) junction. The MSM junction has been formed on the nanogap device that is fabricated on a SOI wafer by optical lithography and KOH solution silicon etching. The Ni evaporated on the surface of the nanogap device performs the metal contact for the junction. The ZnO made by evaporation and thermal oxidation of Zn serves as the semiconductor part to realize efficient excitonic emission. Photon emission phenomenon has been observed when bias is applied to the nano-LED device. The measured IV curve has confirmed the junction structure. The electroluminescence spectrum of the light has been obtained by using monochromator and CCD camera. The spectrum shows broad visual band wavelengths that are believed to result from some intrinsic defects of ZnO. The electroluminescence mechanisms are explained by the recombination of electrons and holes injected through thermionic emission, field emission, and thermionic-field emission.

Development and Performance of a Sparsity-Exploiting Algorithm for Few-View Single Photon Emission Computed Tomogrpahy (SPECT) Reconstruction

Paul Arthur Wolf — Wed, 20 Feb 2013 10:08:27 PST

Single Photon Emission Computed Tomography (SPECT) provides noninvasive images of the distribution of radiotracer molecules. Dynamic Single Photon Emission Computed Tomography provides information about tracer uptake and washout from a series of time-sequence images. Stationary ring-like multi-camera systems are being developed to provide rapid dynamic acquisitions with high temporal sampling. Reducing the number of cameras reduces the cost of such systems but also reduces the number of views acquired, limiting the angular sampling of the system. Novel few-view image reconstruction methods may be beneficial and are being investigated for the application of dynamic SPECT. A sparsity-exploiting algorithm intended for few-view Single Photon Emission Computed Tomography (SPECT) reconstruction is proposed and characterized. The reconstruction algorithm phenomenologically models the object as piecewise constant subject to a blurring operation. To validate that the reconstruction algorithm closely approximates the true object when the object model is known and the system is modeled exactly, projection data were generated from an object assuming this model and using the system matrix. Monte Carlo simulations were performed to provide more realistic data of a phantom with varying smoothness across the field of view. For all simulations, reconstructions were performed across a sweep of the two primary design parameters: the blurring parameter and the weighting of the total variation (TV) minimization term. A range of noise and angular sampling conditions were also investigated. Maximum-Likelihood Expectation Maximization (MLEM) reconstructions were performed to provide a reference image. Spatial resolution, accuracy, and signal-to-noise ratio were calculated and compared for all reconstructions. The results demonstrate that the reconstruction algorithm very closely approximates the true object under ideal conditions. While this reconstruction technique assumes a specific blurring model, the results suggest that the algorithm may provide high reconstruction accuracy even when the true blurring parameter is unknown. In general, increased values of the blurring parameter and TV weighting parameters reduced noise and streaking artifacts, while decreasing spatial resolution. The reconstructed images demonstrate that the reconstruction algorithm introduces low-frequency artifacts in the presence of noise, but eliminates streak artifacts due to angular undersampling. Further, as the number of views was decreased from 60 to 9 the accuracy of images reconstructed using the proposed algorithm varied by less than 3%. Overall, the results demonstrate preliminary feasibility of a sparsity-exploiting reconstruction algorithm which may be beneficial for few-view SPECT.

Analysis of the Detection of Organophosphate Pesticides in Aqueous Solutions Using Polymer-Coated SH-SAW Sensor Arrays

Tian Newman — Wed, 20 Feb 2013 10:03:28 PST

The shear horizontal surface acoustic wave (SH-SAW) device was investigated as a micro-chemical sensor for the direct, rapid and in-situ monitoring of chemical contaminants in groundwater and wastewater. The chemical contaminants of interest are organo-phosphate-based compounds (parathion, parathion-methyl, and paraoxon). The polymers used as partially chemically selective coatings are 2,2’-diallylbisphenol A - 1,1,3,3,5,5-hexamethyltrisiloxane (BPA-HMTS), and 2,2’-diallylbisphenol A- polydimethylsiloxane (BPA-PDMS), polyepichlorohydrin (PECH). The experimental results indicate that the analyte/polymer interaction is a result of mass loading and viscoelastic changes in the polymer. BPA-HMTS, BPA-PDMS, and PECH have the highest to lowest sensitivity towards parathion, parathion-methyl, and paraoxon respectively. The polymers tested at a thickness of 0.5μm show a higher (up to 20 kHz) response than the 0.25μm-thick polymers due to a more pronounced effect of mass loading and modulus change. The response times of the polymers from fast to slow are PECH, BPA-PDMS, and BPA-HMTS, and the order for the analytes is paraoxon, parathion-methyl, and parathion respectively. An array of sensors consisting of devices with different coatings and thicknesses is designed to increase sensor selectivity, which provides a specific pattern for each analyte. Based on visual pattern recognition, analyte identification is performed, using radial plots with the frequency shift and response times of BPA-HMTS, BPA-PDMS, and PECH at a thickness of 0.5μm as input parameters. The concentration of the unknown sample is determined using an algorithm that computes the unknown sample’s distance from the points of the known pattern in the three-dimensional space of the steady-state frequency shifts of the three 0.5μm-thick polymer coatings. The probability of the unknown pattern being identical to the known pattern can be determined by a level of confidence. The sensor is tested for stability, sensitivity, and reproducibility via subjection to a real life application simulation. The sensor is exposed to different interferents such as pH levels of 6.2, 7.0, and 8.0 and red clay. The sensor response to the analytes is shown to be unaffected by the presence of these interferents.

Biomechanical Model of Pediatric Upper Extremity Dynamics During Wheelchair Mobility

Alyssa J. Paul — Tue, 19 Feb 2013 14:59:35 PST

Biomechanical analysis has been used by many to evaluate upper extremity (UE) motion during human movement, including during the use of assistive devices such as crutches and walkers. However, few studies have been conducted to examine the upper extremity kinetics during wheelchair mobility, specifically within the pediatric population. In 2000, 90% of wheelchair users (1.5 million people) in the United States were manual wheelchair users, requiring the use of their upper body to maneuver the wheelchair as well as perform other activities of daily living. Among children under the age of 18, the wheelchair was the most used assistive mobility device at 0.12% of the USA population (about 88,000 children). Of these children, 89.9% (79,000) use manual wheelchairs. Associated with the leading causes of assistive mobility device usage in children and adolescents, are severe cases of osteogenesis imperfecta (OI), cerebral palsy (CP), myelomeningocele (MM) and spinal cord injury (SCI). Once confined to a wheelchair, the upper extremities must take over the responsibilities of the lower extremities, including mobility and other activities of daily living. For many individuals who are wheelchair-bound since childhood, pain and other pathological symptoms present by their mid to late 20’s. Due to increased life expectancy and continual wheelchair use, these injuries may cause the user to have reduced, or loss of, independent function as they age, further decreasing quality-of-life. Better knowledge of upper extremity dynamics during wheelchair propulsion can improve understanding of the onset and propagation of UE pathologies. This may lead to improvements in wheelchair prescription, design, training, and long-term/transitional care. Thereby, pathology onset may be slowed or prevented, and quality of life restored. In order to better understand and model the UE joints during wheelchair mobility three main goals must be accomplished:

1. Create an upper extremity kinematic model including: additional segments, more accurate representations of segments and joint locations, consideration of ease of use in the clinical setting with children.

2. Create the corresponding kinetic model to determine the forces and moments occurring at each joint.

3. Implement the model and collect preliminary data from children with UE pathology.

The Effect of Primary Air Distribution on Emissions from a Natural Gas Water Heater

Hao Wang — Tue, 19 Feb 2013 14:54:20 PST

The NOx emissions of a 40,000 BTU/hr (11.7kW) natural gas water heater are studied at different primary equivalence ratios (Φ). CO emission, O2 content in the flue gas and other related parameters are measured to assess the potential for NOx emission reductions with relatively modest changes in current burner and combustion chamber designs. In addition, N2 is introduced into the primary fuel and air flow to simulate flue gas recirculation (FGR) in order to estimate what benefit such a strategy might provide. NOx concentration in the exhaust decreases from 84 ppm to 34 ppm (at 3% dry O2) when the primary equivalence ratio is decreased from 4.8 to 1.3. The flame structure also varies with primary equivalence ratio. When Φ is lower than 2.1, the flame starts to show a highly unsteady structure, and NOx emissions fluctuate at this range of Φ. However, the observed NOx emissions decrease with a decreasing Φ indicates a potential method of significant NOx reduction in natural gas water heaters if the flame could be stabilized. Introducing 10 standard liters per minute (SLPM) N2 (15% of the primary air at Φ=3) into the primary fuel and air flow further decreases NOx emission levels by 20% to 29%, which indicates that flue gas recirculation (FGR) may be a viable method of reducing NOx of natural gas water heaters using on pancake burners.

Modeling and Control of a Doubly-Fed Induction Generator for Wind Turbine-Generator Systems

Xin Jing — Tue, 19 Feb 2013 14:43:33 PST

Wind energy plays an increasingly important role in the world because it is friendly to the environment. During the last decades, the concept of a variable-speed wind turbine (WT) has been receiving increasing attention due to the fact that it is more controllable and efficient, and has good power quality. As the demand of controllability of variable speed WTs increases, it is therefore important and necessary to investigate the modeling for wind turbine-generator systems (WTGS) that are capable of accurately simulating the behavior of each component in the WTGS. Therefore, this thesis will provide detailed models of a grid-connected wind turbine system equipped with a doubly-fed induction generator (DFIG), which includes the aerodynamic models of the wind turbine, the models of the mechanical transmission system, the DFIG models and the three-phase two-level PWM voltage source converter models. In order to obtain satisfying output power from the WTGS, control strategies are also necessary to be developed based on the previously obtained WTGS models. These control schemes include the grid-side converter control, the generator-side converter control, the maximum power point tracking control and the pitch angle control. The grid-side converter controller is used to keep the DC-link voltage constant and yield a unity power factor looking into the WTGS from the grid-side. The generator-side converter controller has the ability of regulating the torque, active power and reactive power. The maximum power point tracking control is used to provide the reference values for the active power at the stator terminals. The pitch angle control scheme is used to regulate the pitch angle and thus keep the output power at rated value even when the wind speed experiences gusts. Various studies in the literature have reported that two-level converters have several disadvantages compared with three-level converters. Among the disadvantages are high switching losses, high dv/dt, and high total harmonic distortion (THD). Hence, the models and field oriented control schemes for three-level neutral-point-clamped (NPC) converters are also investigated and applied to a WTGS. Besides, an advanced modulation technology, namely, space vector PWM (SVPWM), is also investigated and compared to traditional sinusoidal PWM in a WTGS.

Biomechanical Evaluation of an Optical System for Quantitative Human Motion Analysis

Jeffrey D. Kertis — Tue, 19 Feb 2013 14:36:56 PST

An eight-camera Optitrack motion capture system was evaluated by performing static, linear dynamic, and angular dynamic calibrations using marker distances associated with upper and lower extremity gait and wheelchair models. Data were analyzed to determine accuracy and resolution within a defined capture volume using a standard Cartesian reference system. Two additional cameras along with AMASS and Visual3D (C-Motion, Inc., Germantown, MD) biomechanical modeling software were used to determine joint kinematics at the pelvis, hip, knee, and ankle of ten control subjects (mean age 21.5 ± 1.65 years). The same data were processed through Nexus (Vicon Motion Systems, Oxford, England) modeling software. The joint angle data was statistically compared between the two systems using a variance components model which determined the variability between maximum, minimum, and range values. Static accuracy ranged from 99.31% to 99.90%. Static resolution ranged from 0.04 ± 0.15 mm to 0.63 ± 0.15 mm at the 0.05 level of significance. The dynamic accuracy ranged from 94.82% to 99.77 %, and dynamic resolution ranged from 0.09 ± 0.26 mm to 0.61 ± 0.31 mm at the 0.05 level of significance. These values are comparable to those reported for a standard Vicon 524 (Vicon Motion Systems, Oxford, England) motion analysis system. Gait cycle maximum, minimum, and range values showed no significant difference when comparing Visual3D and Nexus at the pelvis, hip, and knee. Significant differences were seen at the tibia (rotation) and foot due to foot model variations between the two systems. The results support application of the lower cost Optitrack cameras and Visual3D software for 3D kinematic assessment of lower extremity motion during gait. Additional potential applications supported by these findings include other lower extremity models, assisted ambulation, and wheelchair mobility.

The Peers Intervention: Social Anxiety, Physiological Regulation, and Core Autistic Symptoms in Adolescents with Autism

Kirsten A. Schohl — Tue, 19 Feb 2013 14:28:21 PST

There have been very few effective interventions developed that have focused on improving social skills in adolescents with autism spectrum disorders (ASD), however, the need is persistent. This study aimed to evaluate the effectiveness of the Program for the Enrichment and Education of Relational Skills (PEERS: Laugeson, Frankel, Mogil, & Dillon, 2009). PEERS focuses on improving friendship quality and social skills among adolescents, ages 11-15 years, with higher-functioning ASD. This study included 47 participants, who were randomly assigned to two groups. Assessment measures utilized parent report and adolescent self-report at pre- and post-treatment. In addition, respiratory sinus arrhythmia (RSA) was measured at both pre-and post-treatment in order to assess adolescents’ physiological arousal. Results revealed, in comparison to the waitlist control group, that the experimental treatment group significantly improved their knowledge of PEERS concepts and friendship skills, increased in their amount of get-togethers, and displayed less autistic symptoms as reported by parents, from pre-to post-PEERS. RSA was found to significantly decrease over time in both groups, contrary to expectations. This study greatly adds to the minimal literature regarding social skills interventions for adolescents with ASD, as well as suggests further avenues for understanding the complex effect of intervention on physiology in ASD.

Relationship of Facebook Usage to Team Identification

Caitlin Moyer — Mon, 10 Sep 2012 07:22:31 PDT

This study examines the relationship of Facebook usage with sports team identification using Wann's (2006c) "Team Identification-Social Psychological Health Model" to help identify individuals' needs, or motives, for connecting with the team via Facebook as well as with the team itself. To the extent that the team's Facebook presence is believed to fulfill certain needs for an individual, connecting with a team via Facebook was expected to result in higher levels of team identification with that team. Thus, by determining the uses and gratifications that individuals glean from connecting with the team via the social networking site, marketers may be able to determine how to positively impact fans' levels of team identification and ultimately, discretionary spending on the team. This study also begins to explore the relationships of Facebook use and team identification to consumption behavior in the form of game attendance and merchandise purchase. A Facebook usage survey of 571 individuals on the Milwaukee Brewers Baseball Club's email list, combined with the Sport Spectator Identification Scale designed to measure team identification, was conducted to test hypotheses based on these propositions. The analyses performed on the results of the survey indicated significant positive correlations between gratifications sought from the Milwaukee Brewers Facebook page and intention to visit the page; intended and past use of the Milwaukee Brewers Facebook page and team identification; and team identification and consumption behaviors. This study also established a reliable and valid set of measures of the antecedents to team identification.

The Impact of Additional Weather Inputs on Gas Load Forecasting

Bo Pang — Mon, 10 Sep 2012 07:22:29 PDT

Real-Time Transport of Internet Telephony Service Utilizing Embedded Resource-Constrained Systems

Kyle Persohn — Mon, 10 Sep 2012 07:22:27 PDT