Physical Sciences and Mathematics Commons^™

An Object-Oriented Framework For Userland Filesystem Development, George K. Thiruvathukal, Joseph P. Kaylor, Konstantin Läufer

George K. Thiruvathukal

Userland filesystems (also known as virtual/installable filesystems) represent a promising direction for interfacing the traditional filesystem concept to specific domain instances (e.g. finance, bioinformatics, astronomy, photo sharing services, etc.) One might initially be inclined to think of filesystems as “old school” or “so 1980s” but their use remains an established practice in computational science and in many business domains, owing to the stability of filesystems interfaces and the continued perception of having great overall performance. While the promise of building one’s own userland filesystems is great, the approach has seen little adoption, owing to the complexity of working with low-level …

Gendered Jobs And The New Gender Gap, George K. Thiruvathukal, Jon Ross

George K. Thiruvathukal

This presentation discusses how to address 21st Century employment challenges by dismantling gender-specific barriers to entry. We take an interdisciplinary approach by focusing on areas such as education, public policy, culture, and media (among others).

Coarsening In High Order, Discrete, Ill-Posed Diffusion Equations, Catherine Kublik

Catherine Kublik

We study the discrete version of a family of ill-posed, nonlinear diffusion equations of order 2n. The fourth order (n=2) version of these equations constitutes our main motivation, as it appears prominently in image processing and computer vision literature. It was proposed by You and Kaveh as a model for denoising images while maintaining sharp object boundaries (edges). The second order equation (n=1) corresponds to another famous model from image processing, namely Perona and Malik's anisotropic diffusion, and was studied in earlier papers. The equations studied in this paper are high order analogues of the Perona-Malik equation, and like the …

Algorithms For Area Preserving Flows, Catherine Kublik, Selim Esedoglu, Jeffrey A. Fessler

Catherine Kublik

We propose efficient and accurate algorithms for computing certain area preserving geometric motions of curves in the plane, such as area preserving motion by curvature. These schemes are based on a new class of diffusion generated motion algorithms using signed distance functions. In particular, they alternate two very simple and fast operations, namely convolution with the Gaussian kernel and construction of the distance function, to generate the desired geometric flow in an unconditionally stable manner. We present applications of these area preserving flows to large scale simulations of coarsening.

An Implicit Interface Boundary Integral Method For Poisson’S Equation On Arbitrary Domains, Catherine Kublik, Nicolay M. Tanushev, Richard Tsai

Catherine Kublik

We propose a simple formulation for constructing boundary integral methods to solve Poisson’s equation on domains with smooth boundaries defined through their signed distance function. Our formulation is based on averaging a family of parameterizations of an integral equation defined on the boundary of the domain, where the integrations are carried out in the level set framework using an appropriate Jacobian. By the coarea formula, the algorithm operates in the Euclidean space and does not require any explicit parameterization of the boundaries. We present numerical results in two and three dimensions.

Lyapunov Functionals That Lead To Exponential Stability And Instability In Finite Delay Volterra Difference Equations, Catherine Kublik, Youssef Raffoul

Catherine Kublik

We use Lyapunov functionals to obtain sufficient conditions that guarantee exponential stability of the zero solution of the finite delay Volterra difference equation. Also, by displaying a slightly different Lyapunov functional, we obtain conditions that guarantee the instability of the zero solution. The highlight of the paper is the relaxing of the condition |a(t)| < 1. Moreover, we provide examples in which we show that our theorems provide an improvement of some recent results.

Bioactive Surface Modification Of Metal Oxides Via Catechol-Bearing Modular Peptides: Multivalent-Binding, Surface Retention, And Peptide Bioactivity, Wen Tang, Gina Policastro, Geng Hua, Kai Guo, Chrys Wesdemiotis, Gary Doll, Matthew Becker

Gary L. Doll

A series of multivalent dendrons containing a bioactive osteogenic growth peptide (OGP) domain and surface-binding catechol domains were obtained through solid phase synthesis, and their binding affinity to hydroxyapatite, TiO2, ZrO2, CeO2, Fe3O4 and gold was characterized using a quartz crystal microbalance with dissipation (QCM-d). Using the distinct difference in binding affinity of the bioconjugate to the metal oxides, TiO2-coated glass slides were selectively patterned with bioactive peptides. Cell culture studies demonstrated the bioavailability of the OGP and that OGP remained on the surface for at least 2 weeks under in vitro cell culture conditions. Bone sialoprotein (BSP) and osteocalcein …

Detection And Counting Of Micro Scale Particles And Pollen Using A Multi-Aperture Coulter Counter, Ashish Jagtiani, Jiang Zhe, Jun Hu, Joan Carletta

Joan Carletta

We demonstrate a high throughput, all-electronic Coulter-type sensor with four sensing microapertures to detect and count micro-scale particles. Four particle samples are utilized for this study: polymethacrylate particles 40 µm and 20 µm in diameter, Juniper Scopulorum (Rocky Mountain Juniper) pollen and Cottonwood pollen particles. The two types of pollen particles are roughly 20 µm in diameter. The particles are mixed with deionized water and forced to pass through the microapertures. Voltage pulses across all four apertures are recorded and analysed. Results demonstrate that the sensor can detect and count particles through its four sensing apertures simultaneously. Thus, the counting …

Some Issues In Unsupervised Feature Selection Using Similarity., Partha Pratim Kundu Dr.

Doctoral Theses

Pattern recognition is what humans do most of the time, without any conscious effort, and fortunately excel in. Information is received through various sensory organs, processed simultaneously in the brain, and its source is instantaneously identified without any perceptible effort. The interesting issue is that recognition occurs even under non-ideal conditions, i.e., when information is vague, imprecise or incomplete. In reality, most human activities depend on the success in performing various pattern recognition tasks. Let us consider an example. Before boarding a train or bus, we first select the appropriate one by identifying either the route number or its destination …

Precision Measurement Of The Longitudinal Double-Spin Asymmetry For Inclusive Jet Production In Polarized Proton Collisions At √S=200 Gev, James K. Adkins, Renee H. Fatemi, Suvarna Ramachandran, Grant D. Webb, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, D. Arkhipkin, E. C. Aschenauer

Physics and Astronomy Faculty Publications

We report a new measurement of the midrapidity inclusive jet longitudinal double-spin asymmetry, A_LL, in polarized pp collisions at center-of-mass energy √s=200  GeV. The STAR data place stringent constraints on polarized parton distribution functions extracted at next-to-leading order from global analyses of inclusive deep-inelastic scattering (DIS), semi-inclusive DIS, and RHIC pp data. The measured asymmetries provide evidence at the 3σ level for positive gluon polarization in the Bjorken-x region x>0.05.

First Measurement Of The Polarization Observable E In The P→(Γ→,Π+)N Reaction Up To 2.25 Gev, Clas Collaboration, R.A. Badui, Lei Guo

Department of Physics

First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction γ p→π+n, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant deviations are observed, particularly in the high-energy region where high-Lmultipoles contribute. The data have been included in new multipole analyses …

Synthesis And Characterization Of A Family Of Air-Stable Ferrocene- And Ruthenocene-Containing Primary, Secondary, And Tertiary Phosphines, Amir Rabiee Kenaree, Tyler J. Cuthbert, Stephanie M. Barbon, Paul D. Boyle, Elizabeth R. Gillies, Paul J. Ragogna, Joe Gilroy

Chemistry Publications

The synthesis and characterization of a family of air-stable primary, secondary, and tertiary phosphines containing all possible combinations of ethylferrocene and ethylruthenocene substituents are reported. Each phosphine was characterized by ¹H, ¹³C, and ³¹P NMR spectroscopy, IR and UV-vis absorption spectroscopy, mass spectrometry, and elemental analysis. With the exception of primary ethylruthenocene phosphine 8a, all of the title compounds have been studied by single crystal X-ray crystallography. Ferrocene-containing phosphines showed maximum absorption at wavelengths of ca. 440 nm and qualitatively reversible oxidation waves in their cyclic voltammograms with intensities scaling to the number of ferrocene units …

Yinyang Bipolar Quantum Geometry And Bipolar Quantum Superposition Part Ii—Toward An Equilibrium-Based Analytical Paradigm Of Quantum Mechanics And Quantum Biology, Wen-Ran Zhang, Francesco Marchetti

Department of Computer Science Faculty Publications

In Part I of this paper, YinYang bipolar quantum agent (BQA), bipolar quantum geometry (BQG) and 2-dimensional generic bipolar quantum superposition are introduced with a geometrical and logical exposition of Dirac 3-polarizer experiment. While the exposition qualifies BQG as a geometry of light, it is shown in this paper that the logical exposition can be extended to an analytical paradigm of quantum mechanics and quantum biology. It is shown that BQG as the geometry of light is also the geometry of Nature with a logical unification of matter and antimatter atoms into a bipolar quantum cellular automaton (BQCA) through multidimensional …

Yinyang Bipolar Quantum Geometry And Bipolar Quantum Superposition Part I—A Background Independent Geometrical And Logical Exposition Of Dirac 3-Polarizer Experiment, Wen-Ran Zhang, Francesco Marchetti

Department of Computer Science Faculty Publications

Bipolar quantum agent (BQA), bipolar quantum geometry (BQG) and bipolar dynamic logic (BDL) are introduced based on bipolar complementarity – a logical extension to Niels Bohr’s particle-wave YinYang duality principle. Complete geometrical background independence is proposed and BQG is proven completely background independent which leads to the notion of bipolar quantum superposition – an equilibrium-based logical approach to superposition. It is shown that the logical linearity of BDL can be unified with the physical nonlinearity of bipolar dynamic equilibrium. It is proven that a single polarized photon as a BQA can be logically channeled through the three polarizers in Dirac’s …

Synthesis And Electrochemical Performance Of Mn3O4/Graphene Composites, Shan-Shan Yang, Qian Zhang, Xiong-Gui Lin, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

The Mn₃O₄/Graphene composites were synthesized by hydrothermal method with the in-situ redox reaction of graphene oxide (GO) and manganese acetate (Mn(Ac)₂). The phase structures and morphologies of the materials were characterized by XRD, SEM and TEM. The XPS and IR techniques were used for studying the residual function groups of reduced graphene oxide (RGO). The electrochemical performances of the hybrids were tested in a coin cell. Results showed that the composites prepared with the addition of ammonia water (RM-A) have better performance. The graphenes in RM-A were better-reduced and the Mn3O4 particles were much …

Broadband Sum-Frequency Generation Spectroscopic Invstigations Of Thiocyanate On Polycrystalline Au Electrode In Alkaline Solutions, Mei Xu, Jing-Jing Wang, Zhi-Chao Huangfu, Ng Ying Wa, Yu-Han He, Zhao-Hui Wang

Journal of Electrochemistry

Broadband sum frequency generation (BB-SFG) spectroscopy has been used to investigating the potential-dependent adsorption behaviors of thiocyanate ions on polycrystalline Au electrode in alkaline solutions. During the positive scan, a change in the Stark slope (dω_C-N/dE) for C—N stretching mode can be observed in the range of -1.1 V ~ 0.2 V (vs. SCE), which implies that the orientation of adsorbed thiocyanate ions at Au electrode surface changes from N-bound (dω_C-N/dE=45 cm^-1·V^-1) form to S-bound (dω_C-N/dE = 16.2 cm^-1·V^{-1 …}

Effect Of Adsorption Potential On Co Oxidation At Au@Pt Nanoparticles Electrodes, A Surface Enhanced Raman Spectroscopic Study, Pu Zhang, Yi Wei, Yong-Li Zheng, Yan-Xia Chen, Zhong-Qun Tian

Journal of Electrochemistry

The adsorption/oxidation of CO on the 55 nm Au@0.7 nm Pt nanoparticles electrode in both potentiodynamic and potentiostatic modes were investigated by surface enhanced Raman spectroscopy in a thin layer electrochemical flow cell under controlled mass transport, with the aim of clarifying the origin CO oxidation at lower electrode potentials (in current pre-wave region of corresponding cyclic voltammograms). Our results demonstrated that the CO oxidation kinetics differed significantly from the three kinds of different CO adsorption history, with almost no CO oxidation current in the pre-peak potential region after 0.35 V_RHE CO adsorption with or without subsequent holding the …

Structural And Dynamic Studies Of Spinel Lini0.5Mn1.5O4Cathode Material During Initial Charge/Discharge Processes, Qin Wang, Li-Li Zhou, Chong-Heng Shen, Qi Wang, Ling Huang, Jun-Tao Li, Shi-Gang Sun

Journal of Electrochemistry

The spinel LiNi_0.5Mn_1.5O₄ material was synthesized by co-precipitation method with NaOH as a precipitant. The structure and morphology of the as-prepared LiNi_0.5Mn_1.5O₄ materials were characterized by means of XRD、FTIR and SEM. The results indicated that the material belonged to space group and consisted of octahedral particles with the sizes of 3 ~ 6 μm. Electrochemical tests showed the first discharge specific capacity of 121.5 mAh·g^-1 at 0.1C. After 150 cycles, about 99% of reversible capacity was retained for the LiNi_0.5Mn_1.5O₄ material. A combining potentiostatic …

Synthesis, Structure And Electrochemical Performance Of Na2Mnsio4/C Cathode Material For Na-Ion Batteries, Shou-Ding Li, Jiang-Huai Guo, Yong Xie, Jin-Xiao Mi, Yong Yang

Journal of Electrochemistry

As a promising cathode material for sodium ion batteries, pure phase Na₂MnSiO₄/C nanocomposite was successfully synthesized by a sol-gel method with a citric acid as a complex agent. The as prepared material was characterized by XRD, FTIR, SEM and TEM techniques. XRD and Rietveld refinement results indicated that the sample was indexed as monoclinic structure with space group of Pn. It was observed by SEM and TEM that the obtained product consisted of micro-scaled secondary particles, which were composed of NaMnSiO4 nanocrystallites and amorphous carbon network. More importantly, the uniform carbon network in the nanocomposite …

Electrochemical Removal Of Low Concentration Pb(Ii) From Aqueous Solution Based On Ppy/Α-Zrp/Ptcf Electrode, Ru-Yi Chen, Peng-Le Zhang, Sen-Liang Liao, Zhong-De Wang, Xiao-Gang Hao

Journal of Electrochemistry

A novel organic-inorganic hybrid film consisting of polypyrrole/α-zirconium phosphate (PPy/α-ZrP) was prepared in an aqueous phase by cyclic voltammetry method. It was proved by FT-IR, XRD and XPS characterizations that the electroactive PPy/α-ZrP hybrid film was synthesized successfully. The PPy/α-ZrP film electrode prepared on a porous three-dimensional carbon felt (PTCF) was used for removal of a low concentration of Pb(II) ions from an aqueous solution by electrochemically switched ion exchange (ESIX). A quick uptake and release rate of Pb(II) onto the film electrode was obtained by adjusting redox state of the hybrid film. The removal efficiency and adsorption capacity of …

Mechanism Study On The Electrocatalytic Oxidation Of Acetylene To Oxalic Acid, Xiu-Li Song, Rui-Long Jia, Wen-Yan Dong, Zhen-Hai Liang

Journal of Electrochemistry

A new method of electrocatalytic synthesis oxalic acid from acetylene was explored and the synthesized oxalic acid was characterized by Ultraviolet-visible spectrophotometry (Uv-vis) and Infrared spectroscopy (IR). First-principles calculations were carried out to examine the adsorption of acetylene over the Pt(111) surface. The electrocatalytic oxidation behavior of acetylene has been investigated on a Pt electrode by cyclic voltammetry (CV) and steady-state polarization in Na₂SO₄ solution. The formation mechanism of oxalic acid in the Na₂SO₄ solution was proposed and the transfer coefficients of the reaction were calculated. The results show that acetylene molecule tends to …

Reaction Mechanisms Study Of Pb Electrodes In Sulfuric Acid And Sodium Sulfate Solutions By Eqcm, Xian-Ping Zou, Zong-Xuan Kang, Yu-Lan Huang, Dong Shu, Ya-Yun Zhong, Jun-Nan Hao, Yu-Qing Liao

Journal of Electrochemistry

Surface reaction processes of Pb electrodes were investigated in H₂SO₄ and Na₂SO₄ solutions by LSV, CV and EQCM. The results in the voltammogram and the mass change curve of the Pb electrode indicated that the oxide products of lead included PbSO4 and PbO·PbSO₄ in sulfuric acid solution with a positive-going potential scan from -1.0 V to -0.4 V and then PbO·PbSO₄ transformed into PbSO₄. However, the oxide product of lead was only PbSO₄ in sodium sulfate solution. The experimental results revealed that the acid solution is necessary for the …

Preparation And Enhanced Rate Capability Of Spinel Limn1.9Al0.1O3.95F0.05, Jun-Yan Hu, Meng-Meng Wang, Hong-Tao Liu

Journal of Electrochemistry

Spinel LiMn_1.9Al_0.1O_3.95F_0.05 cathode materials with good crystallinity were synthesized by a sol-gel process followed with a high-temperature solid reaction. The effects of partial substitution of Al for Mn, and F for O on the structure and the electrochemical performance were investigated. The results showed that LiMn_1.9Al_0.1O_3.95F_0.05 exhibited the same crystalline state as LiMn₂O₄, but much better electrochemical stability at higher rate cycling. As a result, LiMn_1.9Al_0.1O_3.95F_0.05 could maintain stable electrochemical lithium storage even suffering from …

Generalized Inclusion-Exclusion, Mike W. Ghesquiere

Electronic Thesis and Dissertation Repository

Sets are a foundational structure within mathematics and are commonly used as a building block for more complex structures. Just above this we have functions and sequences before an explosion of increasingly specialized structures. We propose a re-hanging of the tree with hybrid sets (that is, signed multi-sets), as well hybrid functions (functions with hybrid set domains) joining the ranks of sequences and functions. More than just an aesthetic change, this allows symbolic manipulation of structures in ways that might otherwise be cumbersome or inefficient. In particular, we will consider simplifying the product and sum of two piecewise functions or …

On The Estimation Of Intracluster Correlation For Time-To-Event Outcomes In Cluster Randomized Trials, Sumeet Kalia

Electronic Thesis and Dissertation Repository

Cluster randomized trials (CRTs) involve the random assignment of intact social units rather than independent subjects to intervention groups. Time-to-event outcomes often are endpoints in CRTs where the intracluster correlation coefficient (ICC) serves as a descriptive parameter to assess the similarity among outcomes in a cluster. However, estimating the ICC in CRTs with time-to-event outcomes is a challenge due to the presence of censored observations. The ICC is estimated for two CRTs using the censoring indicators and observed outcomes.

A simulation study explores the effect of administrative censoring on estimating the ICC. Results show that the ICC estimators derived from …

Tungsten Carbide/Carbon Electrode Material Synthesized By Block Copolymer Template Method, Xiao-Ling Lang, Ye-Kun Jiang, Mei-Qin Shi, Ling-Zhi Kang, Chun-An Ma

Journal of Electrochemistry

At present, one of the major hurdles for commercialization of system with direct methanol fuel cell (DMFC) is still the requirement of a significant amount of platinum (Pt) catalyst to achieve an acceptable power density. Pt and Pt-based metals are expensive due to limited supplies. In order to find the catalyst alternative to the Pt metal, we selected tungsten carbide (WC) and its composites as the study object. We synthesized WC with carbon materials as the suitable support to modify the electronic structure and to increase the specific surface area of WC. In this study, tungsten carbide/carbon (WC/C) was prepared …

Sodium Difluoro(Oxalato)Borate As An Electrolyte Additive To Improve The Electrochemical Performance Of Graphite Anode, Yang-Yang Yao, Dong-Dong Liu, Li Wang, Xiang-Ming He, Jian-Jun Li, Ding Zhang

Journal of Electrochemistry

The fast development in applications of Li-ion batteries (LiBs) in daily life urges for better electrochemical performance of LiBs, which can be promoted by adding appropriate electrolyte additives. This work studied the effect of NaDFOB as the additive on a common electrolyte formula (1 mol·L^-1 LiPF₆ in EC+DMC+EMC, 1:1:1 by volume). Analysis methods such as CV, EIS and SEM were adopted to study electrochemical performance of experimental battery and interface profiles. It was revealed that the reversible charge-discharge capacity and cycling performance of graphite anode had been dramatically improved. In addition, the cycling performance of graphite anode at …

The Journal Of Electrochemistry Award 2015

Journal of Electrochemistry

No abstract provided.

Preparation And Characterization Of Carbon Supported Pd-Sb Composite Nanocatalysts For Formic Acid Electrooxidation, Long-Long Wang, Xiao-Lu Cao, Ya-Jun Wang, Jin-Hao Ping, Qiao-Xia Li

Journal of Electrochemistry

Palladium is considered as an efficient anode catalyst with high catalytic activity for electrooxidation of formic acid. To further improve the catalytic activity and stability, alloying or surface modification with Sb is an effective way. In this work, the well dispersed carbon supported Pd-Sb composite nanocatalysts (Pd-Sb/C) were synthesized by traditional impregnation reduction method with trisodium citrate as the complexing agent, sodium borohydride as the reducing agent. The morphologies of Pd-Sb/C and the effects of molar ratio of Pd to Sb on the electrocatalytic properties of Pd-Sb/C for HCOOH electrooxidation were studied. The XRD and XPS analyses on the as-prepared …

Effect Of Carbon Nanotubes On Anodic Properties Of Ti/Ru-Ir-Sn Oxides, Feng Lian, Yong-Lei Xin, Bo-Jiang Ma, Li-Kun Xu

Journal of Electrochemistry

The Ru-Ir-Sn metal oxide anodes coated on titanium (Ti/Ru-Ir-Sn) were prepared by thermal decomposition. The effects of amounts of carbon naotubes (CNTs) on anodic properties were studied by TGA, SEM, EDS, cyclic voltammetry, EIS, polarization measurements and accelerated life test. The thermogravimetric analysis and EDS spectrum data showed that the high temperature oxidation decomposition of CNTs did not take place under the condition of the sintering temperature of 470 ℃, and the CNTS still existed in the anode coating in an element form. Compared with the contrast samples, the surface crack of the coating increased, but remained typical morphology. Adding …