Faculty Research & Creative Scholarship 2019: M-N

Journal Title: IEEE Internet of Things Journal

Abstract: Smart City is a key component in Internet of Things (IoTs), so it has attracted much attention. The emergence of Mobile Crowd Sensing (MCS) systems enables many smart city applications. In an MCS system, sensing tasks are allocated to a number of mobile users. As a result, the sensing related context of each mobile user plays a significant role on service quality. However, some important sensing context is ignored in the literature. This motivates us to propose a Context-aware Multi-Armed Bandit (C-MAB) incentive mechanism to facilitate quality-based worker selection in an MCS system. We evaluate a worker’s service quality by its context (i.e., extrinsic ability and intrinsic ability) and cost. Based on our proposed C-MAB incentive mechanism and quality evaluation design, we develop a Modified Thompson Sampling Worker Selection (MTS-WS) algorithm to select workers in a reinforcement learning manner. MTS-WS is able to choose effective workers because it can maintain accurate worker quality information by updating evaluation parameters according to the status of task accomplishment. We theoretically prove that our C-MAB incentive mechanism is selection efficient, computationally efficient, individually rational, and truthful. Finally, we evaluate our MTS-WS algorithm on simulated and real-world datasets in comparison with some other classic algorithms. Our evaluation results demonstrate that MTS-WS achieves the highest cumulative utility of the requester and social welfare.
Author: Liran Ma, Associate Professor, Computer Science

Journal Title: IEEE Transactions on Vehicular Technology

Abstract: In this paper, we consider a centralized cooperative cognitive radio network (CCRN), where a primary base station sends a message to a primary user (PU). Meanwhile, a secondary user transmitter (SU-Tx) acts as a friendly jammer that sends jamming signals (artificial noise) to protect the transmitted message from a potential eavesdropper (Eve). However, the SUTx may not be completely honest in sending jamming signals for selfish reasons, i.e., it may be untrusted. To select a trustworthy SU-Tx as a friendly jammer, we adopt the concept of trust degree as a selection criterion. We investigate the trust degree’s influence on the secrecy performance of a CCRN in cases of perfect channel state information (CSI) and statistical CSI, respectively. In the case of perfect CSI, the accurate expected secrecy rate is derived to evaluate the secrecy performance. In the case of statistical CSI, we calculate the probabilities of the transmission and secrecy outage events, and the secrecy performance is evaluated in terms of effective secrecy throughput. In both cases, we obtain the target trust degree thresholds based on the target secrecy performance thresholds, respectively. Next, we investigate how to calculate the trust degree of each SU-Tx and establish a trust degree list of all SU-Txs. Finally, according to the trust degree list and the target trust degree thresholds, we can select a trustworthy SU-Tx as a friendly jammer in both two cases. A comprehensive simulation study is carried out to validate our secrecy performance analyses and the trust degree management.
Author: Liran Ma, Associate Professor, Computer Science

Originally published in print in October 2010; Audio version published in 2018
Journal Title: Texas Monthly

Synopsis: In partnership with Texas Monthly, Katy Vine's "Just Desserts" is now available as an audio download, where the length and timeliness of a podcast meets the high-quality production of a full-length audio program. Mr. and Mrs. Jenkins led a perfectly adequate middle class life in Corsicana, Texas. Mr. Jenkins, Sandy, worked as an accountant at Collin Street Bakery, world-famous for their fruitcakes. Kay, Mrs. Jenkins, was the more outgoing of the two, the one that friends and neighbors actually noticed and didn't mind talking to. Feelings of adequacy and invisibility weighed on Sandy, and were only compounded by his admiration of boss bakery owner Bob McNutt, a man who reminded him daily that others were respected and were living more luxurious lives than he. One day, Sandy decided to seize a bit of that respect and finer life he admired so much in McNutt for himself. With just a bit of manipulation of the bakery's accounts, Sandy wrote the first of many checks in the company's name to pay for the life of luxury he envisioned was his right. Combining a quintessential tale of living above one's means with the addiction of committing a crime time and again without getting caught, Katy Vine delivers the hard-to-imagine story of the Jenkinses and their mysterious rise through Corsicana society.
Narrator: Lydia Mackay, Assistant Professor, Theatre

Game Description: Smite is a free-to-play, third-person multiplayer online battle arena (MOBA) video game developed and published by Hi-Rez Studios for Microsoft Windows, macOS, PlayStation 4, Nintendo Switch, and Xbox One.[5] In Smite, players control a god, goddess, or other mythological figure and take part in team based combat, using abilities and tactics against other player-controlled gods and non-player-controlled minions.
Voice of Hera: Lydia Mackay, Assistant Professor, Theatre

Journal Title: International Journal of Leadership in Education

Abstract: In this study, graduate students enrolled in an instructional supervision course were taught solution-focused strategies and applied them as they engaged in a clinical supervision cycle with a practicing classroom teacher. Qualitative methods, including in-depth interviews and analysis of written clinical supervision reports, yielded five primary themes: view positively, letting the teacher lead, solution-focused techniques used, confident and need for practice. Although additional research in this area is warranted, this work suggests the use of solution-focused conferencing strategies may aid novice instructional supervisors in helping to promote teacher reflection and improve teachers’ classroom decision-making.
Author: Marla McGhee, Associate Professor, Educational Leadership; Director of the Center for Public Education

Description: Dr. McKinney’s “Service-Learning in the Latino Community” class has performed hundreds of hours of community service outreach, while working to practice their own Spanish language skills. Some of the local community partners these students have worked with include Iglesia San Miguel, International Newcomer Academy, and M.L. Phillips Elementary School. These photobooks document this amazing partnership.
Author: Mary McKinney, Senior Instructor, Spanish and Hispanic Studies

Journal Title: Energy

Abstract: The proliferation of grid-dependent, zero-energy buildings in a region will alter the diurnal electric power demand to a U-shaped demand curve that limits the role of base-load power plants and the flexibility of the electric grid to meet the power demand. Zero-energy buildings that are also grid-independent (GIB-ZEBs) ensure that carbon emissions are curtailed and that the electricity grid will retain its flexibility to make appropriate use of large, base-load power production units. Such buildings incorporate a reliable system for energy storage that supplies the needed energy when the renewable energy source does not. This paper offers a detailed analysis of the power needs, the seasonal energy usage, and the seasonal energy storage requirements of two GIB-ZEBs. The first is located in the South-West part of the USA, where the air-conditioning demand is very high and the second in the North, where the heating demand is very high and the irradiance/insolation is less. Hydrogen storage and battery storage systems were considered for the energy storage requirements of the buildings. Calculations for the two buildings include: the hourly electric power and total energy demand of the building throughout the year; the hourly energy production by a system of photovoltaics; the hourly energy storage needed throughout the year; the photovoltaics area requirements; the overall capacity and seasonal use of the energy storage system needed; and the effects of the various components and systems performance on the power production and storage parameters.
Author: Efstathios E. Michaelides, W.A. "Tex" Moncrief Jr. Founding Chair of Engineering

Journal Title: Energy Conversion and Management

Abstract: Because of their Global Climate Change contributions, it is desirable to reduce the amount of the global CO2 emissions. One of the ways to accomplish this is the substitution of coal with renewable energy sources, most notably wind and solar. However, the availability of wind energy and of insolation does not follow the diurnal and annual demand patterns of electric power. The large-scale substitution of coal with wind and solar significantly shifts the demand for the rest of the power producing units. When the contribution of wind and solar exceeds approximately 25% of the total annual energy produced, there are time periods within a year when excess electricity is produced that must be wasted/dissipated. This presents a severe constraint for the substitution of coal-generated electricity with renewables. At such production levels diurnal or seasonal storage of energy becomes necessary and hydrogen storage offers the best alternative. Based on the hourly, electricity demand of a region in North Texas, which has very high availability of wind and solar energy and is considered prime region for renewables, extensive calculations are made for: (a) the solar and wind rated power that are necessary for the substitution of part or all the power currently supplied by a coal-fired power plant; and (b) the storage requirements for this substitution. Significant seasonal and diurnal energy storage, on the order of 250,000 m3, is required for the total substitution of coal in the region. The calculations also reveal that the substitution of coal with the renewable energy sources may be optimized for minimum energy storage capacity.
Author: Efstathios E. Michaelidesa, W.A. "Tex" Moncrief Jr. Founding Chair of Engineering

Journal Title: Athenaeum Review

Author: Darren J. N. Middleton, John F. Weatherly Professor of Religion; Director, MLA Program Religion

Journal Title: Intégrité

Author: Darren J. N. Middleton, John F. Weatherly Professor of Religion; Director, MLA Program Religion

Journal Title: Early Christianity

Abstract: In the Hellenism of the turn of the common era, τάξις, with its cognate notions and grammatical forms, constitutes a commonplace, understood generally as the “sequenced arrangement” necessary for rhetorical effectiveness. Mark’s Gospel is presented as rhetorically deficient because it lacks such a properly configured arrangement. By contrast, Matthew’s Gospel exhibits a commendable rhetorical narrative production, however difficult it may be for an audience to interpret its Hebrew/Aramaic. Eusebius defends Mark, nevertheless, by invoking the “living and enduring voice” of Peter that resonates clearly enough despite the din of Mark’s dis-organized whole. Matthew is pulled in by Eusebius as a ‘QED’ from “one from those early days,” viz., Papias, to authenticate Mark, not to show Matthew “therefore” needing or intending to improve upon Mark’s inadequacies. In fact, Mark’s basic plot ‘from Galilee to Jerusalem to the cross and raising up,’ as sounded through the voice of Peter, vouchsafes this incipient ‘synoptic’ pattern that will generate the distinctive ‘synoptic family’ of Mark, Matthew, and Luke. It is telling, if not ironic, that in drawing upon John “the elder’s” defense of Mark’s “arrangement,” Eusebius’s apologetic is, finally, an attempt to underwrite Mark within the rubric of Hellenistic narrative rhetoric.
Author: David Paul Moessner, A. A. Bradford Chair and Professor of Religion

Description: David Moessner proposes a new understanding of the relation of Luke's second volume to his Gospel to open up a whole new reading of Luke's foundational contribution to the New Testament. For postmodern readers who find Acts a 'generic outlier, ' dangling tenuously somewhere between the 'mainland' of the evangelists and the 'Peloponnese' of Paul--diffused and confused and shunted to the backwaters of the New Testament by these signature corpora--Moessner plunges his readers into the hermeneutical atmosphere of Greek narrative poetics and elaboration of multi-volume works to inhale the rhetorical swells that animate Luke's first readers in their engagement of his narrative. In this collection of twelve of his essays, re-contextualized and re-organized into five major topical movements, Moessner showcases multiple Hellenistic texts and rhetorical tropes to spotlight the various signals Luke provides his readers of the multiple ways his Acts will follow "all that Jesus began to do and to teach" (Acts 1:1) and, consequently, bring coherence to this dominant block of the New Testament that has long been split apart. By collapsing the world of Jesus into the words and deeds of his followers, Luke re-configures the significance of Israel's "Christ" and the "Reign" of Israel's God for all peoples and places to create a new account of 'Gospel Acts, ' discrete and distinctively different than the "narrative" of the "many" (Luke 1:1). Luke the Historian of Israel's Legacy combines what no analysis of the Lukan writings has previously accomplished, integrating seamlessly two 'generically-estranged' volumes into one new whole from the intent of the one composer. For Luke is the Hellenistic historian and simultaneously 'biblical' theologian who arranges the one "plan of God" read from the script of the Jewish scriptures--parts and whole, severally and together--as the saving 'script' for the whole world through Israel's suffering and raised up "Christ," Jesus of Nazareth. In the introductions to each major theme of the essays, this noted scholar of the Lukan writings offers an epitome of the main features of Luke's theological 'thought, ' and, in a final Conclusions chapter, weaves together a comprehensive synthesis of this new reading of the whole.
Author: David Paul Moessner, A. A. Bradford Chair and Professor of Religion

Description: The chapters in this volume represent the latest thinking on the development and exploration of unconventional energy resources in the U.S., Canada, Australia, Europe, Russia, Asia Pacific, Middle East, Latin America, and Africa and shed light on its potential and future prospects in these respective regions. The diversity of thinking about the “shale revolution” is also evident in our case studies. Throughout many countries in Europe for example, there is a strong preference for investment in renewable sources of energy over the fossil fuels. In addition to environmental concerns, the falling price of renewables, have also made them more attractive financially. Consequently, global investment in renewables is outpacing that of fossil fuel two to one. Watching this trend, in 2017, the Chinese government has pledged to invest $360 billion on renewable energy. This would make China the largest investor in development of renewables in the world. Other obstacles to development of shale oil and gas in other parts of the world include, lack of adequate shale resources (Africa), the abundance of conventional energy resources (Middle East and North Africa), high cost of production (Russia, China, Japan) and political opposition to hydraulic fracturing (France and Poland). Despite these sentiments the economic imperatives (providing employment) also play a significant role in determining the future prospects for unconventional energy resources globally.
Editor: Ken Morgan, Retired Professor, Geological Sciences

Journal Title: Scientific Reports

Abstract:Graphene oxide (GO), the most common derivative of graphene, is an exceptional nanomaterial that possesses multiple physical properties critical for biomedical applications. GO exhibits pH-dependent fluorescence emission in the visible/near-infrared, providing a possibility of molecular imaging and pH-sensing. It is also water soluble and has a substantial platform for functionalization, allowing for the delivery of multiple therapeutics. GO physical properties are modified to enhance cellular internalization, producing fluorescent nanoflakes with low (<15%) cytotoxicity at the imaging concentrations of 15 μg/mL. As a result, at lower flake sizes GO rapidly internalizes into HeLa cells with the following 70% fluorescence based clearance at 24 h, assessed by its characteristic emission in red/near-IR. pH-dependence of GO emission is utilized to provide the sensing of acidic extracellular environments of cancer cells. The results demonstrate diminishing green/red (550/630 nm) fluorescence intensity ratios for HeLa and MCF-7 cancer cells in comparison to HEK-293 healthy cells suggesting a potential use of GO as a non-invasive optical sensor for cancer microenvironments. The results of this work demonstrate the potential of GO as a novel multifunctional platform for therapeutic delivery, biological imaging and cancer sensing.
Author: Anton V. Naumov, Assistant Professor, Physics & Astronomy

Journal Title: Nano Research

Abstract: In this work, we utilize a bottom-up approach to synthesize nitrogen self-doped graphene quantum dots (NGQDs) from a single glucosamine precursor via an eco-friendly microwave-assisted hydrothermal method. Structural and optical properties of as-produced NGQDs are further modified using controlled ozone treatment. Ozone-treated NGQDs (Oz-NGQDs) are reduced in size to 5.5 nm with clear changes in the lattice structure and ID/IG Raman ratios due to the introduction/alteration of oxygen-containing functional groups detected by FTIR and further verified by EDX showing increased atomic/weight percentage of oxygen atoms. Along with structural modifications, GQDs experience decrease in UV-visible absorption coupled with progressive enhancement of visible (up to 16 min treatment) and NIR (up to 45 min treatment) fluorescence. This allows fine-tuning optical properties of NGQDs for solar cell applications yielding controlled emission increase, while controlled emission quenching was achieved by either blue laser or thermal treatment. Optimized Oz-NGQDs were further used to form a photoactive layer of solar cells with a maximum efficiency of 2.64% providing a 6-fold enhancement over untreated NGQD devices and a 3-fold increase in fill factor/current density. This study suggests simple routes to alter and optimize optical properties of scalably produced NGQDs to boost the photovoltaic performance of solar cells.
Author: Anton V. Naumov, Assistant Professor, Physics & Astronomy

Journal Title: Journal of Pure and Applied Algebra

Abstract: Let A be the local ring at a point of a normal complex variety with completion R=Aˆ. Srinivas has asked about the possible images of the induced map ClA→ClR over all geometric local normal domains A with fixed completion R. We use Noether–Lefschetz theory to prove that all finitely generated subgroups are possible in some familiar cases. As a byproduct we show that every finitely generated abelian group appears as the class group of the local ring at the vertex of a cone over some smooth complex variety of each positive dimension.
Author: Scott Nollet, Professor, Mathematics