Physical Sciences and Mathematics Commons^™

The Fierce Green Fire: Vol. 2 Issue 10, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

Likelihood Based Population Independent Component Analysis, Ani Eloyan, Ciprian M. Crainiceanu, Brian S. Caffo

Johns Hopkins University, Dept. of Biostatistics Working Papers

Independent component analysis (ICA) is a widely used technique for blind source separation, used heavily in several scientific research areas including acoustics, electrophysiology and functional neuroimaging. We propose a scalable two-stage iterative true group ICA methodology for analyzing population level fMRI data where the number of subjects is very large. The method is based on likelihood estimators of the underlying source densities and the mixing matrix. As opposed to many commonly used group ICA algorithms the proposed method does not require significant data reduction by a twofold singular value decomposition. In addition, the method can be applied to a large …

Corrected Confidence Bands For Functional Data Using Principal Components, Jeff Goldsmith, Sonja Greven, Ciprian M. Crainiceanu

Johns Hopkins University, Dept. of Biostatistics Working Papers

Functional principal components (FPC) analysis is widely used to decompose and express functional observations. Curve estimates implicitly condition on basis functions and other quantities derived from FPC decompositions; however these objects are unknown in practice. In this paper, we propose a method for obtaining correct curve estimates by accounting for uncertainty in FPC decompositions. Additionally, pointwise and simultaneous confidence intervals that account for both model- based and decomposition-based variability are constructed. Standard mixed-model representations of functional expansions are used to construct curve estimates and variances conditional on a specific decomposition. A bootstrap procedure is implemented to understand the uncertainty in …

Biomimetic Broadband Antireflection Gratings On Solar-Grade Multicrystalline Silicon Wafers, Blayne M. Phillips, Peng Jiang, Bin Jiang

Mathematics and Statistics Faculty Publications and Presentations

The authors report a simple and scalable bottom-up technique for fabricating broadband antireflection gratings on solar-grade multicrystalline silicon (mc-Si) wafers. A Langmuir-Blodgett process is developed to assemble close-packed silica microspheres on rough mc-Si substrates. Subwavelength moth-eye pillars can then be patterned on mc-Si by using the silica microspheres as structural template. Hemispherical reflectance measurements show that the resulting mc-Si gratings exhibit near zero reflection for a wide range of wavelengths. Both experimental results and theoretical prediction using a rigorous coupled-wave analysis model show that close-packed moth-eye arrays exhibit better antireflection performance than non-close-packed arrays due to a smoother refractive index …

Experimental Study Of The Role Of Physicochemical Surface Processing On The In Ability Of Mineral Dust Particles, D. Niedermeier, S. Hartmann, T. Clauss, H. Wex, A. Kiselev, R. C. Sullivan, P. J. Demott, M. D. Petters, P. Reitz, J. Schneider, E. Mikhailov, B. Sierau, O. Stetzer, B. Reimann, U. Bundke, R. A. Shaw, A. Buchholz, T. F. Mentel, F. Stratmann

Michigan Tech Publications, Part 1

During the measurement campaign FROST 2 (FReezing Of duST 2), the Leipzig Aerosol Cloud Interaction Simulator (LACIS) was used to investigate the influence of various surface modifications on the ice nucleating ability of Arizona Test Dust (ATD) particles in the immersion freezing mode. The dust particles were exposed to sulfuric acid vapor, to water vapor with and without the addition of ammonia gas, and heat using a thermodenuder operating at 250 °C. Size selected, quasi monodisperse particles with a mobility diameter of 300 nm were fed into LACIS and droplets grew on these particles such that each droplet contained a …

A Representation Of Selected Nonmanual Signals In American Sign Language, Jerry C. Schnepp

College of Computing and Digital Media Dissertations

Computer-generated three-dimensional animation holds great promise for synthesizing utterances in American Sign Language (ASL) that are not only grammatical, but believable by members of the Deaf community. Animation poses several challenges stemming from the massive amounts of data necessary to specify the movement of three-dimensional geometry, and there is no current system that facilitates the synthesis of nonmanual signals. However, the linguistics of ASL can aid in surmounting the challenge by providing structure and rules for organizing the data.

This work presents a first method for representing ASL linguistic and extralinguistic processes that involve the face. Any such representation must …

Time Evolution Of The Reverse Shock In Sn 1006, P. Frank Winkler, Andrew J. S. Hamilton, Knox S. Long, Robert A. Fesen

Dartmouth Scholarship

The Schweizer-Middleditch star, located behind the SN 1006 remnant and near its center in projection, provides the opportunity to study cold, expanding ejecta within the SN 1006 shell through UV absorption. Especially notable is an extremely sharp red edge to the Si II 1260 Å feature, which stems from the fastest moving ejecta on the far side of the SN 1006 shell—material that is just encountering the reverse shock. Comparing Hubble Space Telescope far-UV spectra obtained with the Cosmic Origins Spectrograph in 2010 and with the Space Telescope Imaging Spectrograph in 1999, we have measured the change in this feature …

Application Of Asymptotic Expansions For Maximum Likelihood Estimators' Errors To Gravitational Waves From Inspiraling Binary Systems: The Network Case, Salvatore Vitale, Michele Zanolin

Publications

This paper describes the most accurate analytical frequentist assessment to date of the uncertainties in the estimation of physical parameters from gravitational waves generated by nonspinning binary systems and Earth-based networks of laser interferometers. The paper quantifies how the accuracy in estimating the intrinsic parameters mostly depends on the network signal to noise ratio (SNR), but the resolution in the direction of arrival also strongly depends on the network geometry. We compare results for 6 different existing and possible global networks and two different choices of the parameter space. We show how the fraction of the sky where the one …

Wave-Function Functionals For The Density, Marlina Slamet, Xiao-Yin Pan, Viraht Sahni

Publications and Research

We extend the idea of the constrained-search variational method for the construction of wave-function functionals psi[chi] of functions chi. The search is constrained to those functions chi such that psi[chi] reproduces the density rho(r) while simultaneously leading to an upper bound to the energy. The functionals are thereby normalized and automatically satisfy the electron-nucleus coalescence condition. The functionals psi[chi] are also constructed to satisfy the electron-electron coalescence condition. The method is applied to the ground state of the helium atom to construct functionals psi[chi] that reproduce the density as given by the Kinoshita correlated wave function. The expectation of single-particle …

Nn/Rise-Based Asymptotic Tracking Control Of Uncertain Nonlinear Systems, Qinmin Yang, Sarangapani Jagannathan, Youxian Sun

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel control methodology for the tracking control of a high-order continuous time nonlinear systems with unknown dynamics and external disturbance. the control signal consists of the robust integral of the sign of the error (RISE) feedback signal multiplied with an adaptive gain plus neural network (NN) output. the two-layer NN learns the system dynamics in an online manner while residual reconstruction errors and the external bounded system disturbances are overcome by the RISE signal. Semi-global asymptotic tracking performance is theoretically guaranteed by using the Lyapunov standard method, while the NN weights and all other signals are …

Dc Pulsed Atmospheric Pressure Plasma Jet Image Information, Denis P. Dowling, F T. O'Neill, Vladimir Milosavljevic, Victor J. Law

Articles

This paper presents optical imaging and optical emission spectroscopy (OES) data of an atmospheric-pressure plasma jet. It is shown how the visual information and OES information of the air discharge are related as the blown arc extends from the nozzle (2-4 mm) with a molecular nitrogen rotational temperature on the order of 1700 K and the flowing afterglow beyond this region is dominated by the cooler (300-K) NO-O chemiluminescent reaction that produces NO₂ species.

An Online Model-Based Fault Diagnosis Scheme For Hvac Systems, Balaje T. Thumati, Miles A. Feinstein, James W. Fonda, Alfred Turnbull, Fay J. Weaver, Mark E. Calkins, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a model-based fault detection and isolation (FDI) scheme with online fault learning capabilities is proposed for HVAC systems. an observer comprising of an online approximator in discrete-time (OLAD) and a robust term is used for detection. a fault is detected if the generated detection residual, which is defined as the error between the observer outputs and HVAC system states, exceeds an apriori chosen threshold. the OLAD term in the FD observer learns the fault dynamics online while the robust term guarantees asymptotic estimation of the system states. Subsequent to detection, a fault isolation observer, which comprises of …

A Secure Data Aggregation Based Trust Management Approach For Dealing With Untrustworthy Motes In Sensor Network, Nayot Poolsappasit, Sanjay Madria

Computer Science Faculty Research & Creative Works

Efficient power management is vital for increasing the life of wireless sensor networks (WSN). the main reason is that the radio transmission consumes energy approximately three times comparing to other operations. Thus, techniques such as data aggregation have been widely used in WSN to preserve energy. Despite its appealing and powerful features, data aggregation requires a high level of security as tampering with aggregating data can be suspected due to small bit errors. We propose a comprehensive trust management approach to deal with the potential dishonest and faulty motes in sensor networks. Unlike other trust management approaches, we take into …

Model-Free H∞ Stochastic Optimal Design For Unknown Linear Networked Control System Zero-Sum Games Via Q-Learning, Hao Xu, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, stochastic optimal strategy for unknown linear networked control system (NCS) quadratic zero-sum games related to H∞ optimal control in the presence of random delays and packet losses is solved in forward-in-time manner. This approach does not require the knowledge of the system matrices since it uses Q-learning. the proposed stochastic optimal control approach, referred as adaptive dynamic programming (ADP), involves solving the action dependent Q-function Q (z, u, d) of the zero-sum game instead of solving the state dependent value function J (z) which satisfies a corresponding Game Theoretic Riccati equation (GRE). an adaptive estimator (AE) is …

Artificial Immune System-Based Diagnostics And Prognostics Scheme And Its Experimental Verification, Gary R. Halligan, Balaje T. Thumati, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel fault diagnostics and prediction (FDP) scheme is introduced by using artificial immune system (AIS) as an online approximator for a class of nonlinear discrete-time systems. Traditionally, AIS is considered as an offline tool for fault detection (FD). However, in this paper, AIS is utilized as an online approximator in discrete time (OLAD) along with a robust adaptive term in the proposed fault diagnostics observer. using the fact that the system outputs are alone measurable, an output residual is determined by comparing the observer and system outputs and a fault is detected if this output residual …

Configuration As A Source Of Information, Joseph W. Houpt, Robert D. Hawkins, Ami Eidels, James T. Townsend, Michael J. Wenger

Psychology Faculty Publications

No abstract provided.

Search-Based Fault Localization, Shaowei Wang, David Lo, Lingxiao Jiang, - Lucia, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Many spectrum-based fault localization measures have been proposed in the literature. However, no single fault localization measure completely outperforms others: a measure which is more accurate in localizing some bugs in some programs is less accurate in localizing other bugs in other programs. This paper proposes to compose existing spectrum-based fault localization measures into an improved measure. We model the composition of various measures as an optimization problem and present a search-based approach to explore the space of many possible compositions and output a heuristically near optimal composite measure. We employ two search-based strategies including genetic algorithm and simulated annealing …

2011 Percival Allen Medal Award, Corina Ionescu, Tudor Berza

Studia UBB Geologia

The Association of European Geological Societies (AEGS) connects geological societies all over Europe. In 2006, the AEGS Executive Committee established an award named for Prof. Percival Allen FRS, one of the AEGS's founders. This medal is given biennially to a geoscientist for outstanding achievements in the field of international relations in Earth Sciences. Other than a distinguished record in fostering international relations in geosciences, there are no special eligibility criteria. The Award Committee announces the laureate at the Meetings of AEGS (MAEGS).

Dr. Jens Dieter Becker-Platen from Germany (at MAEGS-15, held in Tallinn 2007) and Dr. Eduardo de Mulder from …

Cloaking Against Thermal Imaging, Maple So

Mathematical Sciences Technical Reports (MSTR)

There has been a lot of recent interest in cloaking and invisibility in the mathematics and science communities, and in fact physically plausible mechanisms have been proposed (some built) for cloaking an object against detection using a variety of electromagnetic methods. The ideas are very general, however, and should allow one to design cloaks that work against other forms of imaging. We examine the possibility of cloaking an object to make it invisible to an observer using thermal energy (heat) as the imaging tool. Specifically, we desire to cloak an object inside a two-dimensional disk by cutting a small hole …

Search For A New Gauge Boson In Electron-Nucleus Fixed-Target Scattering By The Apex Experiment, S. Abrahamyan, Timothy Holmstrom, Jefferson Lab

Chemistry & Physics Faculty Publications

We present a search at the Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α^′ to electrons. Such a particle A^′ can be produced in electron-nucleus fixed-target scattering and then decay to an e⁺e^- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175–250 MeV, found no evidence for an A^′→e⁺e^- reaction, and set an upper limit of α^′/α≃10^-6. Our findings demonstrate that fixed-target searches can explore a new, …

Density Functional Theory Study On The Electronic Structure Of N- And P-Type Doped Srtio3 At Anodic Solid Oxide Fuel Cell Conditions, Suwit Suthirakun, Salai Cheettu Ammal, Guoliang Xiao, Fanglin Chen, Andreas Heyden, Hans-Conrad Zur Loye

Faculty Publications

The electronic conductivity and thermodynamic stability of mixed n-type and p-type doped SrTiO₃ have been investigated at anodic solid oxide fuel cell (SOFC) conditions using density functional theory (DFT) calculations. In particular, constrained ab initio thermodynamic calculations have been performed to evaluate the phase stability and reducibility of various Nb- and Ga-doped SrTiO₃ at synthesized and anodic SOFC conditions. The density of states (DOS) of these materials was analyzed to study the effects of n- and p-doping on the electronic conductivity. In agreement with experimental observations, we find that the transformation from 20% Nb-doped Sr-deficient SrTiO …

Field-Induced Xy And Ising Ground States In A Quasi-Two-Dimensional S=1/2 Heisenberg Antiferromagnet, Yoshimitsu Kohama, Marcelo Jaime, Oscar E. Ayala-Valenzuela, Ross D. Mcdonald, Eun Deok Mun, Jordan F. Corbey, Jamie L. Manson

Chemistry and Biochemistry Faculty Publications

High field specific heat up to 35 T, C-p, and magnetic susceptibility, chi, measurements were performed on the quasi-two-dimensional (2D) Heisenberg antiferromagnet [Cu(pyz)(2)(pyO)(2)](PF6)(2). While no C-p anomaly is observed down to 0.5 K in zero magnetic field, the application of field parallel to the crystallographic ab-plane induces a lambda-like anomaly in C-p, suggesting Ising-type magnetic order. On the other hand when the field is parallel to the c-axis, C-p and chi show evidence of XY-type antiferromagnetism. This dependence upon the field orientation occurs because the extreme two-dimensionality allows the intrinsic (zero field) spin anisotropy to dominate the interlayer coupling, which …

Case Study In Optimal Dosing In Duodenal Ulcer, Karl E. Peace

Biostatistics: Faculty Publications

Georgia Southern University faculty member Karl E. Peace authored "Case Study in Optimal Dosing in Duodenal Eulcer" in Peptic Ulcer Disease.

Organometallic Acene Complexes For Electronics Applications, Ilya Vinogradov

Kaleidoscope

No abstract provided.

Fundamental Properties Of Simple Emergent Feature Processing, Robert D. Hawkins, Joseph W. Houpt, Ami Eidels, James T. Townsend, Michael J. Wenger

Psychology Faculty Publications

No abstract provided.

The Fierce Green Fire: Vol. 2 Issue 9, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

The Polylogarithm And The Lambert W Functions In Thermoelectrics, Muralikrishna Molli, Kamisetty Venkataramaniah, Sree Ram Valluri

Physics and Astronomy Publications

In this work, we determine the conditions for the extremum of the figure of merit, theta², in a degenerate semiconductor for thermoelectric (TE) applications. We study the variation of the function theta² with respect to the reduced chemical potential mu* using relations involving polylogarithms of both integral and nonintegral orders. We present the relevant equations for the thermopower, thermal, and electrical conductivities that result in optimizing theta² and obtaining the extremum equations. We discuss the different cases that arise for various values of r, which depends on the type of carrier scattering mechanism present in the …

Distance Scale Zero Points From Galactic Rr Lyrae Star Parallaxes, G. Fritz Benedict, Barbara E. Mcarthur, Michael W. Feast, Thomas G. Barnes, Thomas E. Harrison, Jacob L. Bean, John W. Menzies, Brian Chaboyer

Dartmouth Scholarship

We present new absolute trigonometric parallaxes and proper motions for seven Population II variable stars—five RR Lyr variables: RZ Cep, XZ Cyg, SU Dra, RR Lyr, and UV Oct; and two type 2 Cepheids: VY Pyx and κ Pav. We obtained these results with astrometric data from Fine Guidance Sensors, white-light interferometers on Hubble Space Telescope. We find absolute parallaxes in milliseconds of arc: RZ Cep, 2.12 ± 0.16 mas; XZ Cyg, 1.67 ± 0.17 mas; SU Dra, 1.42 ± 0.16 mas; RR Lyr, 3.77 ± 0.13 mas; UV Oct, 1.71 ± 0.10 mas; VY Pyx, 6.44 ± 0.23 …

Investigating The Role Of The Internet In Women And Minority Stem Participation: A Case Study Of Two Florida Engineering Programs, Arland Nguema Ndong

USF Tampa Graduate Theses and Dissertations

Despite our awareness of the fascination modern humans have with the Internet, little is known about how and why colleges and universities create and maintain Websites. At the most general level, in this case study, I hypothesize that university Websites serve as communication and marketing tools in attracting students. At the most specific level, I postulate that civil engineering programs with Web pages depicting images of women and minorities would be more successful in recruiting and retaining women and students of color than civil engineering programs with Web pages displaying fewer or no images of women and minorities. The primary …

Calibration Systems And Methods For Infrared Cameras, Russell Granneman, Nuwan Nagahawatte, Richard M. Goeden, Ted Takagi, Robert Ernst, Gary B. Hughes, Joseph Kostrzewa, John Graff, George Speake, Michael Kent, Neela Nalam, Stephen Lyon, Barbara Sharp, Pierre Boulanger, Neil Cutcliffe, Tim Martin, Ted Hoelter

Statistics

Systems and methods directed to calibration techniques for infrared cameras are disclosed. For example, a method of obtaining calibration information for an infrared device includes providing a calibration target adapted to provide a low-emissivity scene; performing a calibration operation on the infrared device to obtain the calibration information; and storing the calibration information.