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Cascaded Models For Articulated Pose Estimation, Benjamin Sapp, Alexander Toshev, Ben Taskar 2010 University of Pennsylvania

Cascaded Models For Articulated Pose Estimation, Benjamin Sapp, Alexander Toshev, Ben Taskar

Departmental Papers (CIS)

We address the problem of articulated human pose estimation by learning a coarse-to-fine cascade of pictorial structure models. While the fine-level state-space of poses of individual parts is too large to permit the use of rich appearance models, most possibilities can be ruled out by efficient structured models at a coarser scale. We propose to learn a sequence of structured models at different pose resolutions, where coarse models filter the pose space for the next level via their max-marginals. The cascade is trained to prune as much as possible while preserving true poses for the final level pictorial structure model ...


Discourse Indicators For Content Selection In Summaization, Annie Louis, Aravind K. Joshi, Ani Nenkova 2010 University of Pennsylvania

Discourse Indicators For Content Selection In Summaization, Annie Louis, Aravind K. Joshi, Ani Nenkova

Departmental Papers (CIS)

We present analyses aimed at eliciting which specific aspects of discourse provide the strongest indication for text importance. In the context of content selection for single document summarization of news, we examine the benefits of both the graph structure of text provided by discourse relations and the semantic sense of these relations. We find that structure information is the most robust indicator of importance. Semantic sense only provides constraints on content selection but is not indicative of important content by itself. However, sense features complement structure information and lead to improved performance. Further, both types of discourse information prove complementary ...


Using Entity Features To Classify Implicit Discourse Relations, Annie Louis, Aravind K. Joshi, Rashmi Prasad, Ani Nenkova 2010 University of Pennsylvania

Using Entity Features To Classify Implicit Discourse Relations, Annie Louis, Aravind K. Joshi, Rashmi Prasad, Ani Nenkova

Departmental Papers (CIS)

We report results on predicting the sense of implicit discourse relations between adjacent sentences in text. Our investigation concentrates on the association between discourse relations and properties of the referring expressions that appear in the related sentences. The properties of interest include coreference information, grammatical role, information status and syntactic form of referring expressions. Predicting the sense of implicit discourse relations based on these features is considerably better than a random baseline and several of the most discriminative features conform with linguistic intuitions. However, these features do not perform as well as lexical features traditionally used for sense prediction.


A Taxonomy-Based Model For Expertise Extrapolation, Delroy H. Cameron, Boanerges Aleman-Meza, Ismailcem Budak Arpinar, Sheron L. Decker, Amit P. Sheth 2010 Wright State University - Main Campus

A Taxonomy-Based Model For Expertise Extrapolation, Delroy H. Cameron, Boanerges Aleman-Meza, Ismailcem Budak Arpinar, Sheron L. Decker, Amit P. Sheth

Kno.e.sis Publications

While many ExpertFinder applications succeed in finding experts, their techniques are not always designed to capture the various levels at which expertise can be expressed. Indeed, expertise can be inferred from relationships between topics and subtopics in a taxonomy. The conventional wisdom is that expertise in subtopics is also indicative of expertise in higher level topics as well. The enrichment of Expertise Profiles for finding experts can therefore be facilitated by taking domain hierarchies into account. We present a novel semantics-based model for finding experts, expertise levels and collaboration levels in a peer review context, such as composing a Program ...


Ranking Documents Semantically Using Ontological Relationships, Boanerges Aleman-Meza, I. Budak Arpinar, Mustafa V. Nural, Amit P. Sheth 2010 Wright State University - Main Campus

Ranking Documents Semantically Using Ontological Relationships, Boanerges Aleman-Meza, I. Budak Arpinar, Mustafa V. Nural, Amit P. Sheth

Kno.e.sis Publications

Although arguable success of today’s keyword based search engines in certain information retrieval tasks, ranking search results in a meaningful way remains an open problem. In this work, the goal is to use of semantic relationships for ranking documents without relying on the existence of any specific structure in a document or links between documents. Instead, real-world entities are identified and the relevance of documents is determined using relationships that are known to exist between the entities in a populated ontology. We introduce a measure of relevance that is based on traversal and the semantics of relationships that link ...


New Bounds For Restricted Isometry Constants, T. Tony Cai, Lie Wang, Guangwu Xu 2010 University of Pennsylvania

New Bounds For Restricted Isometry Constants, T. Tony Cai, Lie Wang, Guangwu Xu

Statistics Papers

This paper discusses new bounds for restricted isometry constants in compressed sensing. Let Φ be an n × p real matrix and A; be a positive integer with k ≤ n. One of the main results of this paper shows that if the restricted isometry constant δk of Φ satisfies δk <; 0.307 then k-sparse signals are guaranteed to be recovered exactly via ℓ1 minimization when no noise is present and k-sparse signals can be estimated stably in the noisy case. It is also shown that the bound cannot be substantially improved. An explicit example is constructed in which δk = k-1/2k-1 <; 0.5, but it is impossible to recover certain k-sparse signals.


Gibbs Rapidly Samples Colorings Of G(N, D/N), Elchanan Mossel, Allan Sly 2010 University of Pennsylvania

Gibbs Rapidly Samples Colorings Of G(N, D/N), Elchanan Mossel, Allan Sly

Statistics Papers

Gibbs sampling also known as Glauber dynamics is a popular technique for sampling high dimensional distributions defined on graphs. Of special interest is the behavior of Gibbs sampling on the Erdős–Rényi random graph G(n, d/n), where each edge is chosen independently with probability d/n and d is fixed. While the average degree in G(n, d/n) is d(1−o(1)), it contains many nodes of degree of order (log n) / (log log n).

The existence of nodes of almost logarithmic degrees implies that for many natural distributions defined on G(n, d/n) such ...


Detecting Simultaneous Change-Points In Multiple Sequences, Nancy Zhang, David O. Siegmund, Hanlee P. Ji, Jun Li 2010 University of Pennsylvania

Detecting Simultaneous Change-Points In Multiple Sequences, Nancy Zhang, David O. Siegmund, Hanlee P. Ji, Jun Li

Statistics Papers

We discuss the problem of detecting local signals that occur at the same location in multiple one dimensional noisy sequences, with particular attention to relatively weak signals that may occur in only a fraction of the sequences. We propose statistics that combine data across sequences and show that they have better power properties and provide a more easily interpreted summary of the data than do procedures based on a separate analysis for each sequence. In particular, we examine the case where the signal is a temporary shift in the mean of independent Gaussian observations. The formulation of the model is ...


Deep Traps In Algan/Gan Heterostructures Studied By Deep Level Transient Spectroscopy: Effect Of Carbon Concentration In Gan Buffer Layers, Z-Q. Fang, B. Claflin, David C. Look, D. S. Green, R. Vetury 2010 Wright State University - Main Campus

Deep Traps In Algan/Gan Heterostructures Studied By Deep Level Transient Spectroscopy: Effect Of Carbon Concentration In Gan Buffer Layers, Z-Q. Fang, B. Claflin, David C. Look, D. S. Green, R. Vetury

Physics Faculty Publications

Electrical properties, including leakage currents, threshold voltages, and deep traps, of AlGaN/GaN heterostructure wafers with different concentrations of carbon in the GaN buffer layer, have been investigated by temperature dependent current-voltage and capacitance-voltage measurements and deep level transient spectroscopy (DLTS), using Schottky barrier diodes (SBDs). It is found that (i) SBDs fabricated on the wafers with GaN buffer layers containing a low concentration of carbon (low-[C] SBD) or a high concentration of carbon (high-[C] SBD) have similar low leakage currents even at 500 K; and (ii) the low-[C] SBD exhibits a larger (negative) threshold voltage than ...


Modeling Acoustic Scattering From The Seabed Using Transport Theory, Jorge Quijano, Lisa M. Zurk 2010 Portland State University

Modeling Acoustic Scattering From The Seabed Using Transport Theory, Jorge Quijano, Lisa M. Zurk

Electrical and Computer Engineering Faculty Publications and Presentations

Radiative Transfer (RT) theory has established itself as an important tool for electromagnetic remote sensing in parallel plane geometries with random distributions of scatterers, and most recently it has also been proposed as a model for the propagation of elastic waves in layered ocean sediments. In this work the capabilities of this model are illustrated, as the RT method is used to predict backscattering strength from laboratory models of random media. The RT model is characterized by its flexibility on accommodating scatterers in a broad variety of sizes, shapes, and acoustic contrast relative to the background media. Additionally, this formulation ...


The Effectiveness Of Vertebrate Passage And Prevention Structures: A Study Of Boeckman Road In Wilsonville, Catherine E. de Rivera, Leslie L. Bliss-Ketchum 2010 Portland State University

The Effectiveness Of Vertebrate Passage And Prevention Structures: A Study Of Boeckman Road In Wilsonville, Catherine E. De Rivera, Leslie L. Bliss-Ketchum

Environmental Science and Management Faculty Publications and Presentations

One of the most obvious impacts roads have on the natural world is direct mortality to individual animals that attempt to cross roads. A less obvious but likely more important impact of roads on many species is habitat fragmentation. The ability for individuals to travel between subpopulations is the key to genetic diversity as well as ultimately the survival of the species. Considering these impacts and management goals to increase habitat connectivity, increased attention has been given to creating road design that reduces wildlife collisions. Most studies, however, have been in other countries or regions and most focus on connectivity ...


Creative Exercises In General Chemistry: A Student-Centered Assessment, Scott E. Lewis, Janet L. Shaw, Kathryn A. Freeman 2010 Kennesaw State University

Creative Exercises In General Chemistry: A Student-Centered Assessment, Scott E. Lewis, Janet L. Shaw, Kathryn A. Freeman

Faculty Publications

Creative exercises (CEs) are a form of assessment in which students are given a prompt and asked to write down as many distinct, correct, and relevant facts about the prompt as they can. Students receive credit for each fact that they include that is related to the prompt and distinct from the other facts they list. With CEs, students have an opportunity to demonstrate their knowledge and the opportunity to select the information that they believe is related to the prompt. In addition, CEs encourage students to connect concepts because any relevant information presented can assist them in completing the ...


Quiescent X-Ray Emission From Cen X-4: A Variable Thermal Component, Edward M. Cackett, Edward F. Brown, Jon M. Miller, Rudy Wijnands 2010 University of Michigan

Quiescent X-Ray Emission From Cen X-4: A Variable Thermal Component, Edward M. Cackett, Edward F. Brown, Jon M. Miller, Rudy Wijnands

Physics and Astronomy Faculty Research Publications

The nearby neutron star low-mass X-ray binary, Cen X-4, has been in a quiescent state since its last outburst in 1979. Typically, quiescent emission from these objects consists of thermal emission (presumably from the neutron star surface) with an additional hard power-law tail of unknown nature. Variability has been observed during quiescence in Cen X-4 on both timescales as short as hundreds of seconds and as long as years. However, the nature of this variability is still unknown. Early observations seemed to show it was all due to a variable hard X-ray tail. Here, we present new and archival observations ...


Relativistic Lines And Reflection From The Inner Accretion Disks Around Neutron Stars, Edward M. Cackett, Jon M. Miller, David R. Ballantyne, Didier Barret, Sudip Bhattacharyya, Martin Boutelier, M. Coleman Miller, Tod E. Strohmayer, Rudy Wijnands 2010 University of Michigan

Relativistic Lines And Reflection From The Inner Accretion Disks Around Neutron Stars, Edward M. Cackett, Jon M. Miller, David R. Ballantyne, Didier Barret, Sudip Bhattacharyya, Martin Boutelier, M. Coleman Miller, Tod E. Strohmayer, Rudy Wijnands

Physics and Astronomy Faculty Research Publications

A number of neutron star low-mass X-ray binaries (LMXBs) have recently been discovered to show broad, asymmetric Fe K emission lines in their X-ray spectra. These lines are generally thought to be the most prominent part of a reflection spectrum, originating in the inner part of the accretion disk where strong relativistic effects can broaden emission lines. We present a comprehensive, systematic analysis of Suzaku and XMM-Newton spectra of 10 neutron star LMXBs, all of which display broad Fe K emission lines. Of the 10 sources, 4 are Z sources, 4 are atolls, and 2 are accreting millisecond X-ray pulsars ...


Shortest Path Computation On Air Indexes, Georgios KELLARIS, Kyriakos MOURATIDIS 2010 Singapore Management University

Shortest Path Computation On Air Indexes, Georgios Kellaris, Kyriakos Mouratidis

Research Collection School Of Information Systems

Shortest path computation is one of the most common queries in location-based services that involve transportation net- works. Motivated by scalability challenges faced in the mo- bile network industry, we propose adopting the wireless broad- cast model for such location-dependent applications. In this model the data are continuously transmitted on the air, while clients listen to the broadcast and process their queries locally. Although spatial problems have been considered in this environment, there exists no study on shortest path queries in road networks. We develop the rst framework to compute shortest paths on the air, and demonstrate the practicality and ...


Compressed Natural Gas (Cng) Transit Bus Experience Survey: April 2009—April 2010, R. Adams, D. B. Horne 2010 Marathon Technical Services

Compressed Natural Gas (Cng) Transit Bus Experience Survey: April 2009—April 2010, R. Adams, D. B. Horne

Publications (T)

The U.S. Department of Energy (DOE) and the National Renewable Energy Laboratory (NREL) commissioned this survey to collect and analyze experiential data from U.S. transit agencies with varying degrees of compressed natural gas (CNG) bus and station experience. This information helps DOE and NREL determine areas of CNG transit bus success and priority areas for which further technical or other assistance might be required to enable success.

Clean Vehicle Education Foundation (CVEF) staff and subcontractors developed a battery of questions and identified 10 transit agencies to represent all U.S. transit agencies that use CNG buses, accounting for ...


Studies Of Insulating Superconductors, Shawna M. Hollen, J C. Joy, Maura Lynch, H Q. Nguyen, M D. Stewart Jr, J Shainline, Aijun Yin, J M. Xu, J M. Valles Jr. 2010 University of New Hampshire - Main Campus

Studies Of Insulating Superconductors, Shawna M. Hollen, J C. Joy, Maura Lynch, H Q. Nguyen, M D. Stewart Jr, J Shainline, Aijun Yin, J M. Xu, J M. Valles Jr.

Physics Scholarship

No abstract provided.


Macroevolutionary Patterns In The Evolutionary Radiation Of Archosaurs (Tetrapoda: Diapsida), S. L. Brusatte, M. J. Benton, G. T. Lloyd, M. Ruta, Steve C. Wang 2010 Swarthmore College

Macroevolutionary Patterns In The Evolutionary Radiation Of Archosaurs (Tetrapoda: Diapsida), S. L. Brusatte, M. J. Benton, G. T. Lloyd, M. Ruta, Steve C. Wang

Mathematics & Statistics Faculty Works

The rise of archosaurs during the Triassic and Early Jurassic has been treated as a classic example of an evolutionary radiation in the fossil record. This paper reviews published studies and provides new data on archosaur lineage origination, diversity and lineage evolution, morphological disparity, rates of morphological character change, and faunal abundance during the Triassic–Early Jurassic. The fundamental archosaur lineages originated early in the Triassic, in concert with the highest rates of character change. Disparity and diversity peaked later, during the Norian, but the most significant increase in disparity occurred before maximum diversity. Archosaurs were rare components of Early ...


Simulations Of Luminescent Solar Concentrators: Effects Of Polarization And Fluorophore Alignment, S. McDowall, B. L. Johnson, David L. Patrick 2010 Western Washington University

Simulations Of Luminescent Solar Concentrators: Effects Of Polarization And Fluorophore Alignment, S. Mcdowall, B. L. Johnson, David L. Patrick

Chemistry

We model the effects of dye molecule alignment on the collection efficiency of luminescent solar concentrators (LSCs). A Monte Carlo model for photontransport in LSC’s is derived and utilized, which incorporates the effects of fluorescent-dye-molecular alignment and the subsequent control over absorption, emission, and propagation properties. We focus on the effects of molecular alignment statistics on photon absorption and subsequent emission, including polarization and propagation direction imparted by dipole direction, to model device light-capture efficiency, defined as the ratio of the amount of light reaching particular slab edges to that incident on a face. We find that modest control ...


Sfa Weather Station-September 2010, Arthur Temple College of Forestry and Agriculture, Stephen F. Austin State University 2010 Stephen F. Austin State University

Sfa Weather Station-September 2010, Arthur Temple College Of Forestry And Agriculture, Stephen F. Austin State University

Weather Station Data

No abstract provided.


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