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The Origin Of Amino Acids In Lunar Regolith Samples, Jamie E. Elsila, Michael P. Callahan, Jason P. Dworkin, Daniel P. Glavin, Hannah L. Mclain, Sarah K. Noble, Everett K. Gibson Jr.
The Origin Of Amino Acids In Lunar Regolith Samples, Jamie E. Elsila, Michael P. Callahan, Jason P. Dworkin, Daniel P. Glavin, Hannah L. Mclain, Sarah K. Noble, Everett K. Gibson Jr.
Michael Callahan
We analyzed the amino acid content of seven lunar regolith samples returned by the Apollo 16 and Apollo 17 missions and stored under NASA curation since collection using ultrahigh-performance liquid chromatography with fluorescence detection and time-of-flight mass spectrometry. Consistent with results from initial analyses shortly after collection in the 1970s, we observed amino acids at low concentrations in all of the curated samples, ranging from 0.2 parts-per-billion (ppb) to 42.7 ppb in hot-water extracts and 14.5–651.1 ppb in 6 M HCl acid-vapor-hydrolyzed, hot-water extracts. Amino acids identified in the Apollo soil extracts include glycine, d- and l-alanine, d- and l-aspartic …
An Omnibus Nonparametric Test Of Equality In Distribution For Unknown Functions, Alexander Luedtke, Marco Carone, Mark Van Der Laan
An Omnibus Nonparametric Test Of Equality In Distribution For Unknown Functions, Alexander Luedtke, Marco Carone, Mark Van Der Laan
Alex Luedtke
We present a novel family of nonparametric omnibus tests of the hypothesis that two unknown but estimable functions are equal in distribution when applied to the observed data structure. We developed these tests, which represent a generalization of the maximum mean discrepancy tests described in Gretton et al. [2006], using recent developments from the higher-order pathwise differentiability literature. Despite their complex derivation, the associated test statistics can be expressed rather simply as U-statistics. We study the asymptotic behavior of the proposed tests under the null hypothesis and under both fixed and local alternatives. We provide examples to which our tests …
Computerizing Efficient Estimation Of A Pathwise Differentiable Target Parameter, Mark J. Van Der Laan, Marco Carone, Alexander R. Luedtke
Computerizing Efficient Estimation Of A Pathwise Differentiable Target Parameter, Mark J. Van Der Laan, Marco Carone, Alexander R. Luedtke
Alex Luedtke
Frangakis et al. (2015) proposed a numerical method for computing the efficient influence function of a parameter in a nonparametric model at a specified distribution and observation (provided such an influence function exists). Their approach is based on the assumption that the efficient influence function is given by the directional derivative of the target parameter mapping in the direction of a perturbation of the data distribution defined as the convex line from the data distribution to a pointmass at the observation. In our discussion paper Luedtke et al. (2015) we propose a regularization of this procedure and establish the validity …
Capacity Planning With Financial And Operational Hedging In Low‐Cost Countries, Lijian Chen, Shanling Li, Letian Wang
Capacity Planning With Financial And Operational Hedging In Low‐Cost Countries, Lijian Chen, Shanling Li, Letian Wang
Lance (Lijian) Chen
The authors of this paper outline a capacity planning problem in which a risk-averse firm reserves capacities with potential suppliers that are located in multiple low-cost countries. While demand is uncertain, the firm also faces multi-country foreign currency exposures. This study develops a mean-variance model that maximizes the firm’s optimal utility and derives optimal utility and optimal decisions in capacity and financial hedging size. The authors show that when demand and exchange rate risks are perfectly correlated, a risk- averse firm, by using financial hedging, will achieve the same optimal utility as a risk-neutral firm. In this paper as well, …
A Simulation-Based Approach To Solve A Specific Type Of Chance Constrained Optimization, Lijian Chan
A Simulation-Based Approach To Solve A Specific Type Of Chance Constrained Optimization, Lijian Chan
Lance (Lijian) Chen
We solve the chance constrained optimization with convex feasible set through approximating the chance constraint by another convex smooth function. The approximation is based on the numerical properties of the Bernstein polynomial that is capable of effectively controlling the approximation error for both function value and gradient. Thus, we adopt a first-order algorithm to reach a satisfactory solution which is expected to be optimal. When the explicit expression of joint distribution is not available, we then use Monte Carlo approach to numerically evaluate the chance constraint to obtain an optimal solution by probability. Numerical results for known problem instances are …
Re-Solving Stochastic Programming Models For Airline Revenue Management, Lijian Chen, Tito Homem-De-Mello
Re-Solving Stochastic Programming Models For Airline Revenue Management, Lijian Chen, Tito Homem-De-Mello
Lance (Lijian) Chen
We study some mathematical programming formulations for the origin-destination model in airline revenue management. In particular, we focus on the traditional probabilistic model proposed in the literature. The approach we study consists of solving a sequence of two-stage stochastic programs with simple recourse, which can be viewed as an approximation to a multi-stage stochastic programming formulation to the seat allocation problem. Our theoretical results show that the proposed approximation is robust, in the sense that solving more successive two-stage programs can never worsen the expected revenue obtained with the corresponding allocation policy. Although intuitive, such a property is known not …
Ancillary Service Capacity Optimization For Both Electric Power Suppliers And Independent System Operator, Lijian Chen, Dengfeng Sun, Guang Li
Ancillary Service Capacity Optimization For Both Electric Power Suppliers And Independent System Operator, Lijian Chen, Dengfeng Sun, Guang Li
Lance (Lijian) Chen
Ancillary Services (AS) in electric power industry are critical to support the transmission of energy from generators to load demands while maintaining reliable operation of transmission systems in accordance with good utility practice. The ancillary services are procured by the independent system operator (ISO) through a process called the market clearing process which can be modeled by the partial equilibrium from the ends of ISO. There are two capacity optimization problems for both Market participants (MP) and Independent System Operator (ISO). For a market participant, the firm needs to determine the capacity allocation plan for various AS to pursue operating …
Capacity-Driven Pricing Mechanism In Special Service Industries, Lijian Chen, Suraj M. Alexander
Capacity-Driven Pricing Mechanism In Special Service Industries, Lijian Chen, Suraj M. Alexander
Lance (Lijian) Chen
We propose a capacity driven pricing mechanism for several service industries in which the customer behavior, the price demand relationship, and the competition are significantly distinct from other industries. According our observation, we found that the price demand relationship in these industries cannot be modeled by fitted curves; the customers would neither plan in advance nor purchase the service strategically; and the competition would be largely local. We analyze both risk neutral and risk aversion pricing models and conclude the proposed capacity driven model would be the optimal solution under mild assumptions. The resulting pricing mechanism has been implemented at …
Novel Techniques For Enhancing Sensitivity In Static Headspace, Nicholas Snow, G.P Bullock
Novel Techniques For Enhancing Sensitivity In Static Headspace, Nicholas Snow, G.P Bullock
Nicholas A Snow
No abstract provided.
Simultaneous Determination Of Pramoxine Hcl And Benzalkonium Chloride In Wound Care Solutions By Hplc, Panagiotis Tavlarakis, Jonine Greyling, Nicholas Snow
Simultaneous Determination Of Pramoxine Hcl And Benzalkonium Chloride In Wound Care Solutions By Hplc, Panagiotis Tavlarakis, Jonine Greyling, Nicholas Snow
Nicholas A Snow
No abstract provided.
Analysis Of Salvinorin A In Plants, Water, And Urine Using Solid-Phase Microextraction-Comprehensive Two-Dimensional Gas Chromatography–Time Of Flight Mass Spectrometry, Brian Barnes, Nicholas Snow
Analysis Of Salvinorin A In Plants, Water, And Urine Using Solid-Phase Microextraction-Comprehensive Two-Dimensional Gas Chromatography–Time Of Flight Mass Spectrometry, Brian Barnes, Nicholas Snow
Nicholas A Snow
No abstract provided.
Fast Super-Resolution With Affine Motion Using An Adaptive Wiener Filter And Its Application To Airborne Imaging, Russell C. Hardie, Kenneth J. Barnard, Raúl Ordóñez
Fast Super-Resolution With Affine Motion Using An Adaptive Wiener Filter And Its Application To Airborne Imaging, Russell C. Hardie, Kenneth J. Barnard, Raúl Ordóñez
Raúl Ordóñez
Fast nonuniform interpolation based super-resolution (SR) has traditionally been limited to applications with translational interframe motion. This is in part because such methods are based on an underlying assumption that the warping and blurring components in the observation model commute. For translational motion this is the case, but it is not true in general. This presents a problem for applications such as airborne imaging where translation may be insufficient. Here we present a new Fourier domain analysis to show that, for many image systems, an affine warping model with limited zoom and shear approximately commutes with the point spread function …
Research In Mathematics Educational Technology: Current Trends And Future Demands, Shannon O. Driskell, Robert N. Ronau, Christopher R. Rakes, Sarah B. Bush, Margaret L. Niess, David K. Pugalee
Research In Mathematics Educational Technology: Current Trends And Future Demands, Shannon O. Driskell, Robert N. Ronau, Christopher R. Rakes, Sarah B. Bush, Margaret L. Niess, David K. Pugalee
Shannon O.S. Driskell
This systematic review of mathematics educational technology literature identified 1356 manuscripts addressing the integration of educational technology into mathematics instruction. The manuscripts were analyzed using three frameworks (Research Design, Teacher Knowledge, and TPACK) and three supplementary lenses (Data Sources, Outcomes, and NCTM Principles) to produce a database to support future research syntheses and meta-analyses. Preliminary analyses of student and teacher outcomes (e.g., knowledge, cognition, affect, and performance) suggest that the effects of incorporating graphing calculator and dynamic geometry technologies have been abundantly studied; however, the usefulness of the results was often limited by missing information regarding measures of validity, reliability, …
Prospective Teachers' Use Of Representations In Solving Statistical Tasks With Dynamic Statistical Software, Hollylynne Lee, Shannon O. Driskell, Suzanne R. Harper, Keith R. Leatham, Gladis Kersaint, Robin L. Angotti
Prospective Teachers' Use Of Representations In Solving Statistical Tasks With Dynamic Statistical Software, Hollylynne Lee, Shannon O. Driskell, Suzanne R. Harper, Keith R. Leatham, Gladis Kersaint, Robin L. Angotti
Shannon O.S. Driskell
This study examined a random stratified sample (n=62) of prospective teachers' work across eight institutions on three tasks that utilized dynamic statistical software. Our work was guided by considering how teachers may utilize their statistical knowledge and technological statistical knowledge to engage in cycles of investigation. Although teachers did not tend to take full advantage of dynamic linking capabilities, they utilized a large variety of graphical representations and often added statistical measures or other augmentations to graphs as part of their analysis.
Comparing The Model-Simulated Global Warming Signal To Observations Using Empirical Estimates Of Unforced Noise, Patrick T. Brown, Wenhong Li, Eugene C. Cordero, Steven A. Mauget
Comparing The Model-Simulated Global Warming Signal To Observations Using Empirical Estimates Of Unforced Noise, Patrick T. Brown, Wenhong Li, Eugene C. Cordero, Steven A. Mauget
Eugene C. Cordero
The comparison of observed global mean surface air temperature (GMT) change to the mean change simulated by climate models has received much public and scientific attention. For a given global warming signal produced by a climate model ensemble, there exists an envelope of GMT values representing the range of possible unforced states of the climate system (the Envelope of Unforced Noise; EUN). Typically, the EUN is derived from climate models themselves, but climate models might not accurately simulate the correct characteristics of unforced GMT variability. Here, we simulate a new, empirical, EUN that is based on instrumental and reconstructed surface …
Trials Of The Urban Ecologist, Rebecca W. Dolan, Tim Carter, Travis J. Ryan, Carmen M. Salsbury, Thomas E. Dolan, Marjorie Hennessy
Trials Of The Urban Ecologist, Rebecca W. Dolan, Tim Carter, Travis J. Ryan, Carmen M. Salsbury, Thomas E. Dolan, Marjorie Hennessy
Travis J. Ryan
A group of scientists describe some of the obstacles encountered and insights gained while carrying out ecological research in and around the city of Indianapolis.
Quantifying The Basal Conditions Of A Mountain Glacier Using A Targeted Full-Waveform Inversion: Bench Glacier, Alaska, Usa, E. Babcock, J. Bradford
Quantifying The Basal Conditions Of A Mountain Glacier Using A Targeted Full-Waveform Inversion: Bench Glacier, Alaska, Usa, E. Babcock, J. Bradford
John H. Bradford
Glacier dynamics are inextricably linked to the basal conditions of glaciers. Seismic reflection methods can image the glacier bed under certain conditions. However, where a seismically thin layer of material is present at the bed, traditional analyses may fail to fully characterize bed properties. We use a targeted full-waveform inversion algorithm to quantify the basal-layer parameters of a mountain glacier: thickness (d), P-wave velocity (α) and density (ρ). We simultaneously invert for the seismic quality factor (Q) of the bulk glacier ice. The inversion seeks to minimize the difference between the data and a one-dimensional reflectivity algorithm using a gradient-based …
Optimal Ranking Regime Analysis Of Intra- To Multidecadal U.S. Climate Variability. Part I: Temperature, Eugene C. Cordero, Steven A. Mauget
Optimal Ranking Regime Analysis Of Intra- To Multidecadal U.S. Climate Variability. Part I: Temperature, Eugene C. Cordero, Steven A. Mauget
Eugene C. Cordero
The optimal ranking regime (ORR) method was used to identify intradecadal to multidecadal (IMD) time windows containing significant ranking sequences in U.S. climate division temperature data. The simplicity of the ORR procedure’s output—a time series’ most significant nonoverlapping periods of high or low rankings—makes it possible to graphically identify common temporal breakpoints and spatial patterns of IMD variability in the analyses of 102 climate division temperature series. This approach is also applied to annual Atlantic multidecadal oscillation (AMO) and Pacific decadal oscillation (PDO) climate indices, a Northern Hemisphere annual temperature (NHT) series, and divisional annual and seasonal temperature data during …
Optimal Ranking Regime Analysis Of Intra- To Multidecadal U.S. Climate Variability. Part Ii: Precipitation And Streamflow, Steven A. Mauget, Eugene C. Cordero
Optimal Ranking Regime Analysis Of Intra- To Multidecadal U.S. Climate Variability. Part Ii: Precipitation And Streamflow, Steven A. Mauget, Eugene C. Cordero
Eugene C. Cordero
In Part I of this paper, the optimal ranking regime (ORR) method was used to identify intradecadal to multidecadal (IMD) regimes in U.S. climate division temperature data during 1896–2012. Here, the method is used to test for annual and seasonal precipitation regimes during that same period. Water-year mean streamflow rankings at 125 U.S. Hydro-Climatic Data Network gauge stations are also evaluated during 1939–2011. The precipitation and streamflow regimes identified are compared with ORR-derived regimes in the Pacific decadal oscillation (PDO), the Atlantic multidecadal oscillation (AMO), and indices derived from gridded SST anomaly (SSTA) analysis data. Using a graphic display approach …
The Analysis Of Muonium Hyperfine Interaction Measurements Of Thermal Rate Constants For Addition Reactions, Ronald Duchovic, A Wagner, R Turner, D Garner, D Fleming
The Analysis Of Muonium Hyperfine Interaction Measurements Of Thermal Rate Constants For Addition Reactions, Ronald Duchovic, A Wagner, R Turner, D Garner, D Fleming
Ronald J. Duchovic
A new model is developed for the analysis of muon spin relaxation (mu-SR) measurements of muonium (Mu) reaction rates with other chemical species. The kinetics component of the model is specifically developed for addition reactions but can be extended to direct reactions. The polarization component of the model assumes that the adduct formed possesses a single, effective spin precession frequency. The complete model is solved to obtain an analytic expression for the mu-SR signal as a function of time. Both a time-ordered sequence method and a Boltzmann spin equation method give equivalent solutions. These solutions are analyzed under various kinetic …
Teaching College General Chemistry: Techniques Designed To Communicate A Conceptual Framework, Ronald Duchovic
Teaching College General Chemistry: Techniques Designed To Communicate A Conceptual Framework, Ronald Duchovic
Ronald J. Duchovic
General chemistry at the college level is often perceived as a major hurdle by typical undergraduates. Both Freshmen and more advanced students undertake courses in general chemistry either ill-prepared or convinced that the subject matter is beyond their comprehension. With the exception of potential chemistry majors, the vast majority of general chemistry students enter the class simply to satisfy a graduation requirement of their degree program. Consequently, instructors must both communicate an understanding of the subject matter and overcome major barriers to the learning process itself. This paper discusses two techniques which have been utilized for five semesters in general …
Mustard Gas: Its Pre-World War I History, Ronald Duchovic, Joel Vilensky
Mustard Gas: Its Pre-World War I History, Ronald Duchovic, Joel Vilensky
Ronald J. Duchovic
No abstract provided.
Erratum: Theoretical Characterization Of The Potential Energy Surface For H + O2 Ho2* Oh + O. Iii. Computed Points To Define A Global Potential Energy Surface, S Walch, Ronald Duchovic
Erratum: Theoretical Characterization Of The Potential Energy Surface For H + O2 Ho2* Oh + O. Iii. Computed Points To Define A Global Potential Energy Surface, S Walch, Ronald Duchovic
Ronald J. Duchovic
No abstract provided.
A Quasiclassical Trajectory Study Of The Reaction H + O2 Oh + O With The O2 Reagent Vibrationally Excited, Ronald Duchovic, Marla Parker
A Quasiclassical Trajectory Study Of The Reaction H + O2 Oh + O With The O2 Reagent Vibrationally Excited, Ronald Duchovic, Marla Parker
Ronald J. Duchovic
No abstract provided.
Potlib 2001: A Potential Energy Surface Library For Chemical Systems, Ronald Duchovic, Y Volobuev, G Lynch, D Truhlar, T Allison, A Wagner, B Garret, J Corchado
Potlib 2001: A Potential Energy Surface Library For Chemical Systems, Ronald Duchovic, Y Volobuev, G Lynch, D Truhlar, T Allison, A Wagner, B Garret, J Corchado
Ronald J. Duchovic
POTLIB 2001 is a computer program library of global chemical potential energy surface (PES) functions (91 functions in version 1.0) along with test data, a suite of utility programs, and a convenient user interface. The PES programs are written in ANSI standard FORTRAN77 and can be used to determine the Born–Oppenheimer potential energy of chemical systems as a function of the internal coordinates. The accompanying test data allow users to verify local implementations of this library. Finally, the utility programs permit use of this library in conjunction with a variety of chemical dynamics and chemical kinetics computer codes. Interface routines …
Thermal Rate Constants For H + Ch3 Ch4 Recombination. Ii. Comparison Of Experiment And Canonical Variational Transition State Theory, W Hase, S Mondro, Ronald Duchovic, D Hirst
Thermal Rate Constants For H + Ch3 Ch4 Recombination. Ii. Comparison Of Experiment And Canonical Variational Transition State Theory, W Hase, S Mondro, Ronald Duchovic, D Hirst
Ronald J. Duchovic
Canonical variational transition state theory is used to calculate bimolecular rate constants for H + CH, and D + CH, recombination. The calculations are performed on an analytic potential energy surface derived from recent ab initio calculations. Rate constants calculated for this surface are in very good agreement with the experimental values. The H(D)- - -CH3 transitional rocking modes are treated as quantum harmonic oscillators or classical hindered rotors in the calculations. These two treatments give rate constants which agree to within 15%. The variational transition states become tighter as the temperature is increased.
[Erratum] A Correction To The Potlib Library Described In "Potlib 2001: A Potential Energy Surface Library For Chemical Systems": [Computer Physics Communications 144 (2002) 169-187], Ronald Duchovic
Ronald J. Duchovic
No abstract provided.
Venus96: A General Chemical Dynamics Computer Program, W Hase, Ronald Duchovic, X Hu, A Komornicki, K Lim, D-H Lu, G Peslherbe, K Swamy, S Vande Linde, A.J Varandas, H Wang, R Wolf
Venus96: A General Chemical Dynamics Computer Program, W Hase, Ronald Duchovic, X Hu, A Komornicki, K Lim, D-H Lu, G Peslherbe, K Swamy, S Vande Linde, A.J Varandas, H Wang, R Wolf
Ronald J. Duchovic
No abstract provided.
The Fft Method For Determining Semiclassical Eigenvalues: Application To Asymmetric Top Rigid Rotors, Ronald Duchovic, G Schatz
The Fft Method For Determining Semiclassical Eigenvalues: Application To Asymmetric Top Rigid Rotors, Ronald Duchovic, G Schatz
Ronald J. Duchovic
A Fourier transform method for calculating action variables and semiclassical eigenvalues in molecules starting from Cartesian coordinates and momenta is developed and applied to the determination of rotational semiclassical eigenvalues for rigid asymmetric top molecules. The method involves calculating rotational actions by using Fourier representations of the symmetric top action‐angle variables to express the integrals. The question of what is the optimum quantization axis is considered, and it is found that the same primitive semiclassical eigenvalues are obtained independent of which principal axis is used for quantization provided that the replacement J → J+ 1/2 is made. The replacement J …
An Application Of Conventional Transition State `Theory To Compute High--Pressure Limit Thermal Rate Coefficients For The Reaction: H(D) + O2 H(D)O2* Oh(D) + O, Ronald Duchovic, J Pettigrew
An Application Of Conventional Transition State `Theory To Compute High--Pressure Limit Thermal Rate Coefficients For The Reaction: H(D) + O2 H(D)O2* Oh(D) + O, Ronald Duchovic, J Pettigrew
Ronald J. Duchovic
Several ab initio studies have focused on the minimum energy path region of the hydroperoxyl potential energy surface (PES) (J. Chem. Phys. 1988, 88, 6273) and the saddle point region for H-atom exchange via a T-shaped HO2 complex (J. Chem. Phys. 1989, 91, 2373). Further, the results of additional calculations (J. Chem. Phys. 1991, 94, 7068) have been reported which, when combined with the earlier studies, provide a global description (but not an analytic representation) of the PES for this reaction. In this work, information at the stationary points of the ab initio PES is used within the framework of …