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Full-Text Articles in Physical Sciences and Mathematics

Incremental And Decremental Svm For Regression, Honorius Gâlmeanu, Lucian Mircea Sasu, Rǎzvan Andonie Dec 2016

Incremental And Decremental Svm For Regression, Honorius Gâlmeanu, Lucian Mircea Sasu, Rǎzvan Andonie

All Faculty Scholarship for the College of the Sciences

Training a support vector machine (SVM) for regression (function approximation) in an incremental/decremental way consists essentially in migrating the input vectors in and out of the support vector set with specific modification of the associated thresholds. We introduce with full details such a method, which allows for defining the exact increments or decrements associated with the thresholds before vector migrations take place. Two delicate issues are especially addressed: the variation of the regularization parameter (for tuning the model performance) and the extreme situations where the support vector set becomes empty. We experimentally compare our method with several regression methods: the …


Size And Site Dependence Of The Catalytic Activity Of Iridium Clusters Towards Ethane Dehydrogenation, Yingbin Ge, Hao Jiang, Russell Kato, Prasuna Gummagatta Nov 2016

Size And Site Dependence Of The Catalytic Activity Of Iridium Clusters Towards Ethane Dehydrogenation, Yingbin Ge, Hao Jiang, Russell Kato, Prasuna Gummagatta

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This research focuses on optimizing transition metal nanocatalyst immobilization and activity to enhance ethane dehydrogenation. Ethane dehydrogenation, catalyzed by thermally stable Irn (n = 8, 12, 18) atomic clusters that exhibit a cuboid structure, was studied using the B3LYP method with triple-ζ basis sets. Relativistic effects and dispersion corrections were included in the calculations. In the dehydrogenation reaction Irn + C2H6 → H−Irn−C2H5 → (H)2−Irn−C2H4, the first H-elimination is the rate-limiting step, primarily because the reaction releases sufficient heat to facilitate …


Plate Boundary Observatory And Related Networks: Gps Data Analysis Methods And Geodetic Products, Thomas A. Herring, Timothy I. Melbourne, Mark H. Murray, Michael A. Floyd, Walter M. Szeliga, Robert W. King, David A. Phillips, Christine M. Puskas, Marcelo Santillan, Lei Wang Oct 2016

Plate Boundary Observatory And Related Networks: Gps Data Analysis Methods And Geodetic Products, Thomas A. Herring, Timothy I. Melbourne, Mark H. Murray, Michael A. Floyd, Walter M. Szeliga, Robert W. King, David A. Phillips, Christine M. Puskas, Marcelo Santillan, Lei Wang

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The Geodesy Advancing Geosciences and EarthScope (GAGE) Facility Global Positioning System (GPS) Data Analysis Centers produce position time series, velocities, and other parameters for approximately 2000 continuously operating GPS receivers spanning a quadrant of Earth’s surface encompassing the high Arctic, North America, and Caribbean. The purpose of this review is to document the methodology for generating station positions and their evolution over time and to describe the requisite trade-offs involved with combination of results. GAGE GPS analysis involves formal merging within a Kalman filter of two independent, loosely constrained solutions: one is based on precise point positioning produced with the …


A Direct, Early Stage Guanidinylation Protocol For The Synthesis Of Complex Aminoguanidine-Containing Natural Products, Christopher E. Malmberg, Stephen Chamberland Sep 2016

A Direct, Early Stage Guanidinylation Protocol For The Synthesis Of Complex Aminoguanidine-Containing Natural Products, Christopher E. Malmberg, Stephen Chamberland

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The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important structural element found in many complex natural products and pharmaceuticals. Owing to the continual discovery of new guanidinecontaining natural products and designed small molecules, rapid and efficient guanidinylation methods are of keen interest to synthetic and medicinal organic chemists. Because the nucleophilicity and basicity of guanidines can affect subsequent chemical transformations, traditional, indirect guanidinylation is typically pursued. Indirect methods commonly employ multiple protection steps involving a latent amine precursor, such as an azide, phthalimide, or carbamate. By …


Superconducting And Normal State Properties Of The Systems La1−Xmxpt4ge12 (M=Ce,Th), K. Huang, D. Yazici, Benjamin D. White, I. Jeon, A. J. Breindel, N. Pouse, M. B. Maple Sep 2016

Superconducting And Normal State Properties Of The Systems La1−Xmxpt4ge12 (M=Ce,Th), K. Huang, D. Yazici, Benjamin D. White, I. Jeon, A. J. Breindel, N. Pouse, M. B. Maple

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Electrical resistivity, magnetization, and specific heat measurements were performed on polycrystalline samples of the filled-skutterudite systems La1xMxPt4Ge12 (M = Ce and Th). Superconductivity in LaPt4Ge12 was quickly suppressed with Ce substitution and no evidence for superconductivity was found down to 1.1 K for x > 0.2. Temperature-dependent specific heat data at low temperatures for La1xCexPt4Ge12 show a change from powerlaw to exponential behavior, which may be an indication for multiband superconductivity in LaPt4Ge12. …


Advances In Mobile Video Networking, Qi Wang, Guojun Wang, Chrisos Grecos, Ansgar Gerlicher Aug 2016

Advances In Mobile Video Networking, Qi Wang, Guojun Wang, Chrisos Grecos, Ansgar Gerlicher

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Video applications have been increasingly dominating worldwide mobile network traffic in the last years. The growing popularity of smart phones and other mobile devices, on demand and surveillance video services, multimedia social networking, the latest advances in video coding and transmission, and the significant increase in mobile network capacity have all contributed to this global phenomenon. Both challenges and opportunities have emerged in multiple research disciplines involving video signal processing, 4G such as LTE (Long Term Evolution) and even 5G mobile networks, mobile cloud computing, Big Visual Data, mobile user experience, and so on. Research in these leading-edge areas has …


Super-Intelligence Challenges And Lossless Visual Representation Of High-Dimensional Data, Boris Kovalerchuk Jul 2016

Super-Intelligence Challenges And Lossless Visual Representation Of High-Dimensional Data, Boris Kovalerchuk

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Fundamental challenges and goals of the cognitive algorithms are moving super-intelligent machines and super-intelligent humans from dreams to reality. This paper is devoted to a technical way to reach some specific aspects of super-intelligence that are beyond the current human cognitive abilities. Specifically the proposed technique is to overcome inabilities to analyze a large amount of abstract numeric high-dimensional data and finding complex patterns in these data with a naked eye. Discovering patterns in multidimensional data using visual means is a long-standing problem in multiple fields and Data Science and Modeling in general. The major challenge is that we cannot …


Comparison Of Formulations Of Applied Tasks With Intervals, Fuzzy Sets And Probability Approaches, Boris Kovalerchuk, Vladik Kreinovich Jul 2016

Comparison Of Formulations Of Applied Tasks With Intervals, Fuzzy Sets And Probability Approaches, Boris Kovalerchuk, Vladik Kreinovich

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The focus of this paper is to clarify the concepts of solutions in linear equations in interval, probabilistic and fuzzy sets setting for real word tasks. There is a fundamental difference between formal definitions of the solutions and physically meaningful concept of solution in applied tasks when equations have uncertain components. For instance, a formal definition of the solution in terms of Moore interval analysis can be completely irrelevant for solving a real world task. We show that formal definitions must follow meaningful concept of the solution in the real world. The paper proposed several formalized definitions of the concept …


Using Wastewater-Based Epidemiology To Estimate Drug Consumption—Statistical Analyses And Data Presentation, Caleb J. Banta-Green, Alex J. Brewer, Christoph Ort, Dennis R. Helsel, Jason R. Williams, Jennifer A. Field Jun 2016

Using Wastewater-Based Epidemiology To Estimate Drug Consumption—Statistical Analyses And Data Presentation, Caleb J. Banta-Green, Alex J. Brewer, Christoph Ort, Dennis R. Helsel, Jason R. Williams, Jennifer A. Field

All Faculty Scholarship for the College of the Sciences

Aim

Analysis of wastewater samples can be used to assess population drug use, but reporting and statistical issues have limited the utility of the approach for epidemiology due to analytical results that are below the limit of quantification or detection. Unobserved or non-quantifiable—censored—data are common and likely to persist as the methodology is applied to more municipalities and a broader array of substances. We demonstrate the use of censored data techniques and account for measurement errors to explore distributions and annual estimates of the daily mean level of drugs excreted per capita.

Measurements

Daily 24-hour composite wastewater samples for 56 …


Gps Constraints On Interplate Locking Within The Makran Subduction Zone, Elyse Frohling, Walter Szeliga Apr 2016

Gps Constraints On Interplate Locking Within The Makran Subduction Zone, Elyse Frohling, Walter Szeliga

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The Makran subduction zone is one of the last convergent margins to be investigated using space-based geodesy. While there is a lack of historical and modern instrumentation in the region, a sparse sampling of continuous and campaign measurements over the past decade has allowed us to make the first estimates of convergence rates. We combine GPS measurements from 20 stations located in Iran, Pakistan and Oman along with hypocentral locations from the International Seismological Centre to create a preliminary 3-D estimate of the geometry of the megathrust, along with a preliminary fault-coupling model for the Makran subduction zone. Using a …


Investigation Of Superconducting And Normal-State Properties Of The Filled-Skutterudite System Prpt4ge12−Xsbx, I. Jeon, K. Huang, D. Yazici, N. Kanchanavatee, Benjamin D. White, P.-C. Ho, S. Jang, N. Pouse, M. B. Maple Mar 2016

Investigation Of Superconducting And Normal-State Properties Of The Filled-Skutterudite System Prpt4ge12−Xsbx, I. Jeon, K. Huang, D. Yazici, N. Kanchanavatee, Benjamin D. White, P.-C. Ho, S. Jang, N. Pouse, M. B. Maple

All Faculty Scholarship for the College of the Sciences

We report a study of the superconducting and normal-state properties of the filled-skutterudite system PrPt4Ge12−xSbx . Polycrystalline samples with Sb concentrations up to x = 5 were synthesized and investigated by means of x-ray diffraction, electrical resistivity, magnetic susceptibility, and specific heat measurements. We observed a suppression of superconductivity with increasing Sb substitution up to x = 4, above which no signature of superconductivity was observed down to 140 mK. The Sommerfeld coefficient, γ , of superconducting specimens decreases with increasing x up to x = 3, suggesting that superconductivity may depend on the …


Twentieth-Century Warming Preserved In A Geladaindong Mountain Ice Core, Central Tibetan Plateau, Yulan Zhang, Shichang Kang, Bjorn Grigholm, Yongjun Zhang, Susan Kaspari, Uwe Morgenstern, Jiawen Ren, Dahe Qin, Paul A. Mayewski, Qianggong Zhang, Zhiyuan Cong, Mika Sillanpää, Margit Schwikowski, Feng Chen Mar 2016

Twentieth-Century Warming Preserved In A Geladaindong Mountain Ice Core, Central Tibetan Plateau, Yulan Zhang, Shichang Kang, Bjorn Grigholm, Yongjun Zhang, Susan Kaspari, Uwe Morgenstern, Jiawen Ren, Dahe Qin, Paul A. Mayewski, Qianggong Zhang, Zhiyuan Cong, Mika Sillanpää, Margit Schwikowski, Feng Chen

All Faculty Scholarship for the College of the Sciences

High-resolution δ18O records from a Geladaindong mountain ice core spanning the period 1477-1982 were used to investigate past temperature variations in the Yangtze River source region of the central Tibetan Plateau (TP). Annual ice-core δ18O records were positively correlated with temperature data from nearby meteorological stations, suggesting that the δ18O record represented the air temperature in the region. A generally increasing temperature trend over the past 500 years was identified, with amplified warming during the 20th century. A colder stage, spanning before the 1850s, was found to represent the Little Ice Age with colder …