Physical Sciences and Mathematics | Open Access Articles

Computer Intensive Methods Lecture 9, Shuangge Ma

Shuangge Ma

No abstract provided.

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Service Oriented Architecture, William Osei-Poku

William Osei-Poku

No abstract provided.

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"Implementation Of Quasi-Least Squares With The R Package Qlspack", Jichun Xie, Justine Shults

UPenn Biostatistics Working Papers

Quasi-least squares (QLS) is an alternative method for estimating the correlation parameters within the framework of generalized estimating equations (GEE) that has two main advantages over the moment estimates that are typically applied for GEE: (1) It guarantees a consistent estimate of the correlation parameter and a positive definite estimated correlation matrix, for several correlation structures; and (2) It allows for easier implementation of some correlation structures that have not yet been implemented in the framework of GEE. Furthermore, because QLS is a method in the framework of GEE, existing software can be employed within the QLS algorithm for estimation …

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Cloud Particle Size Distributions Measured With An Airborne Digital In-Line Holographic Instrument, J. P. Fugal, R. A. Shaw

Michigan Tech Publications

Holographic data from the prototype airborne digital holographic instrument HOLODEC (Holographic Detector for Clouds), taken during test flights are digitally reconstructed to obtain the size (equivalent diameters in the range 23 to 1000 μm), three-dimensional position, and two-dimensional image of ice particles and then ice particle size distributions and number densities are calculated using an automated algorithm with minimal user intervention. The holographic method offers the advantages of a well-defined sample volume size that is not dependent on particle size or airspeed, and offers a unique method of detecting shattered particles. The holographic method also allows the volume sample rate …

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Using Timed-Release Cryptography To Mitigate The Preservation Risk Of Embargo Periods, Rabia Haq, Michael L. Nelson

Computer Science Presentations

PDF of a powerpoint presentation from the 2009 ACM/IEEE Joint Conference on Digital Libraries, Austin, Texas, June 15-19, 2009. Also available on Slideshare.

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Computer Intensive Methods Lecture 8, Shuangge Ma

Shuangge Ma

No abstract provided.

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Characterization Of An N2 Flowing Microwave Post-Discharge By Oes Spectroscopy And Determination Of Absolute Ground-State Nitrogen Atom Densities By Talif, Et. Es-Sebbar, Y. Benilan, A. Jolly, M-C. Gazeau

Dr. Et-touhami Es-sebbar

A flowing microwave post-discharge source sustained at 2.45 GHz in pure nitrogen has been investigated by optical emission spectroscopy (OES) and two-photon absorption laser-induced fluorescence (TALIF) spectroscopy. Variations of the optical emission along the post-discharge (near, pink and late afterglow) have been studied and the gas temperature has been determined. TALIF spectroscopy has been used in the late afterglow to determine the absolute ground-state nitrogen atomic densities using krypton as a reference gas. Measurements show that the microwave flowing post-discharge is an efficient source of N (4S) atoms in late afterglow. In our experimental conditions, the maximum N (4S) density …

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Reference: Counter Examples [Bootstrap], Shuangge Ma

Shuangge Ma

No abstract provided.

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On The Existence And Uniqueness Of The Maximum Likelihood Estimators Of Normal And Lognormal Population Parameters With Grouped Data, Jin Xia, Jie Mi, Yan Yan Zhou

Department of Mathematics and Statistics

Lognormal distribution has abundant applications in various fields. In literature, most inferences on the two parameters of the lognormal distribution are based on Type-I censored sample data. However, exact measurements are not always attainable especially when the observation is below or above the detection limits, and only the numbers of measurements falling into predetermined intervals can be recorded instead. This is the so-called grouped data. In this paper, we will show the existence and uniqueness of the maximum likelihood estimators of the two parameters of the underlying lognormal distribution with Type-I censored data and grouped data. The proof was first …

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Nutrient Limitation On Phytoplankton Growth In The Upper Barataria Basin, Louisiana: Microcosm Bioassays, Ling Ren, Nancy N. Rabalais, R. Eugene Turner, Wendy Morrison, Warren Mendenhall

Faculty Publications

The Davis Pond Diversion (DPD) was constructed to divert Mississippi River (MR) water into the Barataria Basin to reduce the salinity in support of wetland restoration on the Louisiana coast. To assess the phytoplankton nutrient limitation in adjacent water systems and potential impacts of DPD, 12 seasonal nutrient-phytoplankton bioassay experiments were conducted from October 2003 to July 2004 using the natural phytoplankton assemblages from freshwater and brackish-water lakes, Cataouatche and Salvador, LA (USA), which receive Mississippi River water from the DPD, and from a nearby freshwater lake, Lac des Allemands, that does not. Dissolved inorganic nitrogen (N), phosphorus (P), and …

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A Context-Aware Approach Based On Self-Organizing Maps To Study Web-Users' Tendencies From Their Behaviour, Luca Longo, Stephen Barrett

Conference papers

In the context of a highly volatile web of uneven quality, the identification of content deemed valuable by end users is of paramount importance. Where page content undergoes rapid change, this issue is particularly challenging. Web browsing activity represents a unique source of context by which the value of web pages can be determined via an assessment of individual user interactions, such as scrolling, clicking, saving and so forth. Over time, this data set forms a pattern of activity which can be mined for meaning. In this paper we present an approach to web content, based on Kohonen mapping, used …

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Analysis And Monetization Of Social Data, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Extending Sparql To Support Spatially And Temporally Related Information, Prateek Jain, Amit P. Sheth, Peter Z. Yeh, Kunal Verma

Kno.e.sis Publications

No abstract provided.

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On The Existence And Uniqueness Of The Maximum Likelihood Estimators Of Normal And Lognormal Population Parameters With Grouped Data, Jin Xia, Jie Mi, Yanyan Zhou

Department of Mathematics and Statistics

Lognormal distribution has abundant applications in various fields. In literature, most inferences on the two parameters of the lognormal distribution are based on Type-I censored sample data. However, exact measurements are not always attainable especially when the observation is below or above the detection limits, and only the numbers of measurements falling into predetermined intervals can be recorded instead. This is the so-called grouped data. In this paper, we will show the existence and uniqueness of the maximum likelihood estimators of the two parameters of the underlying lognormal distribution with Type-I censored data and grouped data. The proof was first …

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A Functional Framework For Content Management, Robert Emer Broadbent

Theses and Dissertations

This thesis proposes a functional framework for content management. This framework provides concepts and vocabulary for analysis and description of content management systems. The framework is derived from an analysis of eight content management systems. It describes forty-five conceptual functions organized into five functional groups. The functionality derived from the analysis of the content management systems is described using the vocabulary provided by the functional framework. Coverage of the concepts in the existing systems is verified. The utility of the framework is validated through the creation of a prototype that implements sufficient functionality to support a set of specific use …

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Novel Cinchona Alkoloid Derived Ammonium Salts As Phase-Transfer Catalysts For The Asymmetric Synthesis Of Beta-Hydroxy Alpha-Amino Acids Via Aldol Reactions And Total Synthesis Of Celogentin C., Bing Ma

Theses and Dissertations

Project I. Cinchona alkaloid-derived quaternary ammonium salts have been successfully used as phase-transfer catalysts, particularly in asymmetric alkylations. Our group applied this type of catalyst in the synthesis of β-hydroxy α-amino acids via aldol reactions and discovered that the Park-Jew catalyst afforded good yields and good enantiomeric excess of the syn diasteromers, but negligible diastereoselectivity. This project was therefore focused on the synthesis of novel cinchonidine-derived catalysts with the Park-Jew catalyst as the lead structure. The C3 position of cinchonidine nucleus was modified to achieve dimers and catalysts possessing electron-deficient alkyne and alkene moieties. Synthesized catalysts were tested in the …

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Fusion Of The Parastrophic Matrix And Weak Cayley Table, Nathan C. Perry

Theses and Dissertations

The parastrophic matrix and Weak Cayley Tables are matrices that have close ties to the character table. Work by Ken Johnson has shown that fusion of groups induces a relationship between the character tables of the groups. In this paper we will demonstrate a similar induced relationship between the parastrophic matrices and Weak Cayley Tables of the fused groups.

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Computer Intensive Methods Lecture 7 (Lab 2), Shuangge Ma

Shuangge Ma

No abstract provided.

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U.S. Law Of The Sea Cruise To Map The Eastern Mendocino Ridge, Eastern Pacific Ocean, James V. Gardner, Mashkoor A. Malik

Center for Coastal and Ocean Mapping

No abstract provided.

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Discrete Variable Methods For Delay-Differential Equations With Threshold-Type Delays, Z. Jackiewicz, Barbara Zubik-Kowal

Mathematics Faculty Publications and Presentations

We study numerical solution of systems of delay-differential equations in which the delay function, which depends on the unknown solution, is defined implicitly by the threshold condition. We study discrete variable numerical methods for these problems and present error analysis. The global error is composed of the error of solving the differential systems, the error from the threshold conditions and the errors in delay arguments. Our theoretical analysis is confirmed by numerical experiments on threshold problems from the theory of epidemics and from population dynamics.

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A Cox-2 Inhibitor Nimesulide Analog Selectively Induces Apoptosis In Her2 Overexpressing Breast Cancer Cells Via Cytochrome C Dependent Mechanisms, Bin Chen, Bin Su, Shiuan Chen

Chemistry Faculty Publications

Epidemiological and animal model studies have suggested that non-steroidal anti-inflammatory drugs (NSAIDs) can act as chemopreventive agents. The cyclooxygenase-2 (COX-2) inhibitor nimesulide shows anti-cancer effect in different type of cancers. In the current study, five breast carcinoma cell lines were used to explore the anti-cancer mechanisms of a nimesulide derivative compound 76. The compound dose dependently suppressed SKBR-3, BT474 and MDA-MB-453 breast cancer cell proliferation with IC50 of 0.9 μM, 2.2 μM and 4.0 μM, respectively. However, it needs much higher concentrations to inhibit MCF-7 and MDA-MB-231 breast cancer cell growth with IC50 at 22.1 μM and 19.6 μM, respectively. …

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Stability And Asymptoticity Of Volterra Difference Equations: A Progress Report, Saber Elaydi

Mathematics Faculty Research

We survey some of the fundamental results on the stability and asymptoticity of linear Volterra difference equations. The method of Ζ-transform is heavily utilized in equations of convolution type. An example is given to show that uniform asymptotic stability does not necessarily imply exponential stabilty. It is shown that the two notions are equivalent if the kernel decays exponentially. For equations of nonconvolution type, Liapunov functions are used to find explicit criteria for stability. Moreover, the resolvent matrix is defined to produce a variation of constants formula. The study of asymptotic equivalence for difference equations with infinite delay is carried …

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Cauchy-Characteristic Patching With Improved Accuracy, Maria Babiuc-Hamilton

Physics Faculty Research

Cauchy-characteristic extractions (CCE) avoids the errors due to extraction at finite worldtube. The Cauchy and the characteristic approaches have complementary strengths and weaknesses. Unification of the two methods is a promising way of combining the strengths of both formalisms.

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The Initial And Final States Of Electron And Energy Transfer Processes: Diabatization As Motivated By System-Solvent Interactions, Joseph E. Subotnik, Robert J. Cave, Ryan P. Steele, Neil Shenvi

All HMC Faculty Publications and Research

For a system which undergoes electron or energy transfer in a polar solvent, we define the diabatic states to be the initial and final states of the system, before and after the nonequilibrium transfer process. We consider two models for the system-solvent interactions: A solvent which is linearly polarized in space and a solvent which responds linearly to the system. From these models, we derive two new schemes for obtaining diabatic states from ab initio calculations of the isolated system in the absence of solvent. These algorithms resemble standard approaches for orbital localization, namely, the Boys and Edmiston–Ruedenberg (ER) formalisms. …

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Comparing Bootstrap And Jackknife Variance Estimation Methods For Area Under The Roc Curve Using One-Stage Cluster Survey Data, Allison Dunning

Theses and Dissertations

The purpose of this research is to examine the bootstrap and jackknife as methods for estimating the variance of the AUC from a study using a complex sampling design and to determine which characteristics of the sampling design effects this estimation. Data from a one-stage cluster sampling design of 10 clusters was examined. Factors included three true AUCs (.60, .75, and .90), three prevalence levels (50/50, 70/30, 90/10) (non-disease/disease), and finally three number of clusters sampled (2, 5, or 7). A simulated sample was constructed for each of the 27 combinations of AUC, prevalence and number of clusters. Estimates of …

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Computer Intensive Methods Lecture 6, Shuangge Ma

Shuangge Ma

No abstract provided.

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Reference: Block Jackknife, Shuangge Ma

Shuangge Ma

No abstract provided.

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Hydrazinecarbothioamide Group In The Synthesis Of Heterocycles, Ashraf A. Aly, Alan B. Brown, Talaatt Ibrahim El-Emary, Ashraf M. Mohamed Ewas, Mohamed Ramadan

Chemistry and Chemical Engineering Faculty Publications

The review summarizes recent literatures dealing with hydrazinecarbothioamide group in thiocarbohydrazides and other derivatives including their physical and chemical properties along with their applications in the synthesis of heterocycles.

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Do All Raindrops Fall At Terminal Speed?, Guillermo Montero-Martinez, Alexander Kostinski, Raymond Shaw, Fernando Garcia-Garcia

Department of Physics Publications

A unique relation between raindrop size and fall speed v_t(D) is assumed throughout atmospheric science. Yet, our speed versus size measurements of millions of drops during natural rainfall events show that many intermediate sized raindrops fall up to an order of magnitude faster than expected. Furthermore, images of drop clusters reveal that these “super‐terminal drops” are differently sized fragments of a recent break‐up, moving with the speed of the parent drop and relaxing towards v_t(D). Additional evidence of the break‐up conjecture includes: (i) positive skewness in the distribution of fall speed deviations, …

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Seismic Observations Of Transient Subglacial Water-Flow Beneath Macayeal Ice Stream, West Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley

All Faculty Scholarship for the College of the Sciences

New seismic observations of harmonic tremors beneath MacAyeal Ice Stream, West Antarctica are reported. Each of the two tremor events that we recorded during a six week period had sustained arrival of 3 Hz energy for approximately 10 minutes. During that time the source location migrated a few kilometers. The harmonic nature of the tremors is interpreted as the result of resonance in subglacial water-filled cracks and conduits. The duration, monochromatic nature, and movement of the tremor indicate that the source mechanism is likely flow in the subglacial water system resulting from the discharge from a small subglacial lake. Our …

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Full-Text Articles in Physical Sciences and Mathematics

Computer Intensive Methods Lecture 9, Shuangge Ma

Shuangge Ma

Service Oriented Architecture, William Osei-Poku

William Osei-Poku

"Implementation Of Quasi-Least Squares With The R Package Qlspack", Jichun Xie, Justine Shults

UPenn Biostatistics Working Papers

Cloud Particle Size Distributions Measured With An Airborne Digital In-Line Holographic Instrument, J. P. Fugal, R. A. Shaw

Michigan Tech Publications

Using Timed-Release Cryptography To Mitigate The Preservation Risk Of Embargo Periods, Rabia Haq, Michael L. Nelson

Computer Science Presentations

Computer Intensive Methods Lecture 8, Shuangge Ma

Shuangge Ma

Characterization Of An N2 Flowing Microwave Post-Discharge By Oes Spectroscopy And Determination Of Absolute Ground-State Nitrogen Atom Densities By Talif, Et. Es-Sebbar, Y. Benilan, A. Jolly, M-C. Gazeau

Dr. Et-touhami Es-sebbar

Reference: Counter Examples [Bootstrap], Shuangge Ma

Shuangge Ma

On The Existence And Uniqueness Of The Maximum Likelihood Estimators Of Normal And Lognormal Population Parameters With Grouped Data, Jin Xia, Jie Mi, Yan Yan Zhou

Department of Mathematics and Statistics

Nutrient Limitation On Phytoplankton Growth In The Upper Barataria Basin, Louisiana: Microcosm Bioassays, Ling Ren, Nancy N. Rabalais, R. Eugene Turner, Wendy Morrison, Warren Mendenhall

Faculty Publications

A Context-Aware Approach Based On Self-Organizing Maps To Study Web-Users' Tendencies From Their Behaviour, Luca Longo, Stephen Barrett

Conference papers

Analysis And Monetization Of Social Data, Amit P. Sheth

Kno.e.sis Publications

Extending Sparql To Support Spatially And Temporally Related Information, Prateek Jain, Amit P. Sheth, Peter Z. Yeh, Kunal Verma

Kno.e.sis Publications

On The Existence And Uniqueness Of The Maximum Likelihood Estimators Of Normal And Lognormal Population Parameters With Grouped Data, Jin Xia, Jie Mi, Yanyan Zhou

Department of Mathematics and Statistics

A Functional Framework For Content Management, Robert Emer Broadbent

Theses and Dissertations

Novel Cinchona Alkoloid Derived Ammonium Salts As Phase-Transfer Catalysts For The Asymmetric Synthesis Of Beta-Hydroxy Alpha-Amino Acids Via Aldol Reactions And Total Synthesis Of Celogentin C., Bing Ma

Theses and Dissertations

Fusion Of The Parastrophic Matrix And Weak Cayley Table, Nathan C. Perry

Theses and Dissertations

Computer Intensive Methods Lecture 7 (Lab 2), Shuangge Ma

Shuangge Ma

U.S. Law Of The Sea Cruise To Map The Eastern Mendocino Ridge, Eastern Pacific Ocean, James V. Gardner, Mashkoor A. Malik

Center for Coastal and Ocean Mapping

Discrete Variable Methods For Delay-Differential Equations With Threshold-Type Delays, Z. Jackiewicz, Barbara Zubik-Kowal

Mathematics Faculty Publications and Presentations

A Cox-2 Inhibitor Nimesulide Analog Selectively Induces Apoptosis In Her2 Overexpressing Breast Cancer Cells Via Cytochrome C Dependent Mechanisms, Bin Chen, Bin Su, Shiuan Chen

Chemistry Faculty Publications

Stability And Asymptoticity Of Volterra Difference Equations: A Progress Report, Saber Elaydi

Mathematics Faculty Research

Cauchy-Characteristic Patching With Improved Accuracy, Maria Babiuc-Hamilton

Physics Faculty Research

The Initial And Final States Of Electron And Energy Transfer Processes: Diabatization As Motivated By System-Solvent Interactions, Joseph E. Subotnik, Robert J. Cave, Ryan P. Steele, Neil Shenvi

All HMC Faculty Publications and Research

Comparing Bootstrap And Jackknife Variance Estimation Methods For Area Under The Roc Curve Using One-Stage Cluster Survey Data, Allison Dunning

Theses and Dissertations

Computer Intensive Methods Lecture 6, Shuangge Ma

Shuangge Ma

Reference: Block Jackknife, Shuangge Ma

Shuangge Ma

Hydrazinecarbothioamide Group In The Synthesis Of Heterocycles, Ashraf A. Aly, Alan B. Brown, Talaatt Ibrahim El-Emary, Ashraf M. Mohamed Ewas, Mohamed Ramadan

Chemistry and Chemical Engineering Faculty Publications

Do All Raindrops Fall At Terminal Speed?, Guillermo Montero-Martinez, Alexander Kostinski, Raymond Shaw, Fernando Garcia-Garcia

Department of Physics Publications

Seismic Observations Of Transient Subglacial Water-Flow Beneath Macayeal Ice Stream, West Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley

All Faculty Scholarship for the College of the Sciences