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175,364 full-text articles. Page 3628 of 4568.

How Pearls Are Made: A New Perspective, Otto Vogl 2011 University of Massachusetts - Amherst

How Pearls Are Made: A New Perspective, Otto Vogl

Otto Vogl

No abstract provided.


Topic Models For Taxonomies, Anton Bakalov, Andrew McCallum, Hanna M. Wallach, David Minmo 2011 University of Massachusetts - Amherst

Topic Models For Taxonomies, Anton Bakalov, Andrew Mccallum, Hanna M. Wallach, David Minmo

Andrew McCallum

Concept taxonomies such as MeSH, the ACM Computing Classification System, and the NY Times Subject Headings are frequently used to help organize data. They typically consist of a set of concept names organized in a hierarchy. However, these names and structure are often not sufficient to fully capture the intended meaning of a taxonomy node, and particularly non-experts may have difficulty navigating and placing data into the taxonomy. This paper introduces two semi-supervised topic models that automatically augment a given taxonomy with many additional keywords by leveraging a corpus of multi-labeled documents. Our experiments show that users find the topics ...


Health Insurance Coverage, Medical Expenditure And Coping Strategy: Evidence From Taiwan, Shuangge Ma 2011 Yale University

Health Insurance Coverage, Medical Expenditure And Coping Strategy: Evidence From Taiwan, Shuangge Ma

Shuangge Ma

No abstract provided.


Picosecond Rotationally Resolved Stimulated Emission Pumping Spectroscopy Of No, Chakree Tanjaroon, Scott Reeve, Alan Ford Ford, W. Dean Murray, Kevin Lyon, Bret Yount, Dan Britton, William Burns, Susan D. Allen, J. Bruce Johnson 2011 Kettering University

Picosecond Rotationally Resolved Stimulated Emission Pumping Spectroscopy Of No, Chakree Tanjaroon, Scott Reeve, Alan Ford Ford, W. Dean Murray, Kevin Lyon, Bret Yount, Dan Britton, William Burns, Susan D. Allen, J. Bruce Johnson

Scott Reeve

No abstract provided.


A Study Of Heating And Cooling Of The Ism In Ngc 1097 With Herschel-Pacs And Spitzer-Irs, P. Beirão, L. Armus, G. Helou, P. N. Appleton, J.-D. T. Smith, K. V. Croxall, E. J. Murphy, D. A. Dale, B. T. Draine, M. G. Wolfire, K. M. Sandstrom, G. Aniano, A. D. Bolatto, B. Groves, B. R. Brandl, E. Schinnerer, A. F. Crocker, J. L. Hinz, H.-W. Rix, R. C. Kennicutt, Daniela Calzetti, A. Gil de Paz, G. Dumas, M. Galametz, K. D. Gordon, C.-N. Hao, B. Johnson, J. Koda, O. Krause, T. van der Laan, A. K. Leroy, Y. Li, S. E. Meidt, J. D. Meyer, N. Rahman, H. Roussel, M. Sauvage, S. Srinivasan, L. Vigroux, F. Walter, B. E. Warren 2011 University of Massachusetts - Amherst

A Study Of Heating And Cooling Of The Ism In Ngc 1097 With Herschel-Pacs And Spitzer-Irs, P. Beirão, L. Armus, G. Helou, P. N. Appleton, J.-D. T. Smith, K. V. Croxall, E. J. Murphy, D. A. Dale, B. T. Draine, M. G. Wolfire, K. M. Sandstrom, G. Aniano, A. D. Bolatto, B. Groves, B. R. Brandl, E. Schinnerer, A. F. Crocker, J. L. Hinz, H.-W. Rix, R. C. Kennicutt, Daniela Calzetti, A. Gil De Paz, G. Dumas, M. Galametz, K. D. Gordon, C.-N. Hao, B. Johnson, J. Koda, O. Krause, T. Van Der Laan, A. K. Leroy, Y. Li, S. E. Meidt, J. D. Meyer, N. Rahman, H. Roussel, M. Sauvage, S. Srinivasan, L. Vigroux, F. Walter, B. E. Warren

Daniela Calzetti

NGC 1097 is a nearby Seyfert 1 galaxy with a bright circumnuclear starburst ring, a strong large-scale bar and an active nucleus. We present a detailed study of the spatial variation of the far infrared (FIR) [CII]158um and [OI]63um lines and mid-infrared H2 emission lines as tracers of gas cooling, and of the polycyclic aromatic hydrocarbon (PAH) bands as tracers of the photoelectric heating, using Herschel-PACS, and Spitzer-IRS infrared spectral maps. We focus on the nucleus and the ring, and two star forming regions (Enuc N and Enuc S). We estimated a photoelectric gas heating efficiency ([CII]158um ...


Scene Text Recognition With Bilateral Regression, Jacqueline Feild, Erik G. Learned-Miller 2011 University of Massachusetts - Amherst

Scene Text Recognition With Bilateral Regression, Jacqueline Feild, Erik G. Learned-Miller

Erik G Learned-Miller

This paper focuses on improving the recognition of text in images of natural scenes, such as storefront signs or street signs. This is a difficult problem due to lighting conditions, variation in font shape and color, and complex backgrounds. We present a word recognition system that addresses these difficulties using an innovative technique to extract and recognize foreground text in an image. First, we develop a new method, called bilateral regression, for extracting and modeling one coherent (although not necessarily contiguous) region from an image. The method models smooth color changes across an image region without being corrupted by neighboring ...


Momentum Budget Of The Migrating Diurnal Tide In The Whole Atmosphere Community Climate Model At Vernal Equinox, Xian Lu, Alan Z. Liu, Han-Li Liu, Jie Yue 2011 University of Colorado at Boulder

Momentum Budget Of The Migrating Diurnal Tide In The Whole Atmosphere Community Climate Model At Vernal Equinox, Xian Lu, Alan Z. Liu, Han-Li Liu, Jie Yue

Alan Z Liu

No abstract provided.


Subsurface Facies Analysis Of The Late Cambrian Mt. Simon Sandstone In Western Ohio (Midcontinent, U.S.A.), James E. Evans 2011 Bowling Green State University - Main Campus

Subsurface Facies Analysis Of The Late Cambrian Mt. Simon Sandstone In Western Ohio (Midcontinent, U.S.A.), James E. Evans

James E. Evans

No abstract provided.


Three-Dimensional Structural Evolution And Kinematics Of The Piedemonte Llanero, Central Llanos Foothills, Eastern Cordillera, Colombia, Obi Egbue, James N. Kellogg 2011 University of South Carolina

Three-Dimensional Structural Evolution And Kinematics Of The Piedemonte Llanero, Central Llanos Foothills, Eastern Cordillera, Colombia, Obi Egbue, James N. Kellogg

James N Kellogg

The Piedemonte Llanero is a wedge duplex zone in the Llanos foothills on the eastern flank of the Eastern Cordillera of Colombia. It is located northeast of the Cusiana and Cupiagua hydrocarbon fields. The area is characterized by a series of moderate to high-angle duplexes with east-southeast verging thin-skinned and thick-skinned tectonics.We present a structural model constrained by 2-D and 3-D seismic reflection data, surface geology, and well data. The structural analysis is based on backward modeling (kinematic restoration) and forward modeling using transfer-flexural slip and fault slip fold algorithms. The structures are significantly tighter in the northern segment ...


Mapping Lava Flows From Nyamuragira Volcano (1967-2011) With Satellite Data And Automated Classification Methods, Elisabet Head, Ann L. MacLean, Simon A. Carn 2011 Eastern Illinois University

Mapping Lava Flows From Nyamuragira Volcano (1967-2011) With Satellite Data And Automated Classification Methods, Elisabet Head, Ann L. Maclean, Simon A. Carn

Elisabet Head

The volume, location and extent of historical lava flows are important when assessing volcanic hazards, as well as the productivity or longevity of a volcanic system. We use a Landsat/Hyperion/ALI dataset and automated classification methods to map lava flows at Nyamuragira volcano (1967-2011) in the Democratic Republic of the Congo. The humid tropical climate ofNyamuragira is advantageous because its lava flows are emplaced onto heavily forested flanks, resulting in strong contrast between lava and vegetation, which contributes to efficient flow mapping. With increasing age, there is an increase in Landsat band-4 reflectance, suggesting lava flow revegetation with time ...


The Source Counts Of Submillimetre Galaxies Detected At 1.1 Mm, K. S. Scott, Grant W. Wilson, I. Aretxaga, J. E. Austermann, E. L. Chapin, J. S. Dunlop, H. Ezawa, M. Halpern, B. Hatsukade, D. H. Hughes, R. Kawabe, S. Kim, K. Kohno, J. D. Lowenthal, A. Montaña, K. Nakanishi, T. Oshima, D. Sanders, D. Scott, N. Scoville, Y. Tamura, D. Welch, M. S. Yun, M. Zeballos 2011 University of Massachusetts - Amherst

The Source Counts Of Submillimetre Galaxies Detected At 1.1 Mm, K. S. Scott, Grant W. Wilson, I. Aretxaga, J. E. Austermann, E. L. Chapin, J. S. Dunlop, H. Ezawa, M. Halpern, B. Hatsukade, D. H. Hughes, R. Kawabe, S. Kim, K. Kohno, J. D. Lowenthal, A. Montaña, K. Nakanishi, T. Oshima, D. Sanders, D. Scott, N. Scoville, Y. Tamura, D. Welch, M. S. Yun, M. Zeballos

Grant Wilson

The source counts of galaxies discovered at sub-millimetre and millimetre wavelengths provide important information on the evolution of infrared-bright galaxies. We combine the data from six blank-field surveys carried out at 1.1 mm with AzTEC, totalling 1.6 square degrees in area with root-mean-square depths ranging from 0.4 to 1.7 mJy, and derive the strongest constraints to date on the 1.1 mm source counts at flux densities S(1100) = 1-12 mJy. Using additional data from the AzTEC Cluster Environment Survey to extend the counts to S(1100) ~ 20 mJy, we see tentative evidence for an enhancement ...


Quest For Cosmos Submillimeter Galaxy Counterparts Using Carma And Vla: Identifying Three High-Redshift Starburst Galaxies, V. Smolčić, F. Navarrete, M. Aravena, O. Ilbert, M. S. Yun, K. Sheth, M. Salvato, H. J. McCracken, Diener C., I. Aretxaga, D. A. Riechers, A. Finoguenov, F. Bertoldi, P. Capak, D. Hughes, A. Karim, E. Schinnerer, N. Z. Scoville, Grant Wilson 2011 University of Massachusetts - Amherst

Quest For Cosmos Submillimeter Galaxy Counterparts Using Carma And Vla: Identifying Three High-Redshift Starburst Galaxies, V. Smolčić, F. Navarrete, M. Aravena, O. Ilbert, M. S. Yun, K. Sheth, M. Salvato, H. J. Mccracken, Diener C., I. Aretxaga, D. A. Riechers, A. Finoguenov, F. Bertoldi, P. Capak, D. Hughes, A. Karim, E. Schinnerer, N. Z. Scoville, Grant Wilson

Grant Wilson

We report on interferometric observations at 1.3 mm at 2"-3" resolution using the Combined Array for Research in Millimeter-wave Astronomy (CARMA). We identify multi-wavelength counterparts of three submillimeter galaxies (SMGs; F(1mm)>5.5 mJy) in the COSMOS field, initially detected with MAMBO and AzTEC bolometers at low, ~10"-30", resolution. All three sources -- AzTEC/C1, Cosbo-3 and Cosbo-8 -- are identified to coincide with positions of 20 cm radio sources. Cosbo-3, however, is not associated with the most likely radio counterpart, closest to the MAMBO source position, but that further away from it. This illustrates the need for ...


A Relative Entropy Rate Method For Path Space Sensitivity Analysis Of Stationary Complex Stochastic Dynamics, Yannis Pantazis, Markos Katsoulakis 2011 University of Massachusetts - Amherst

A Relative Entropy Rate Method For Path Space Sensitivity Analysis Of Stationary Complex Stochastic Dynamics, Yannis Pantazis, Markos Katsoulakis

Markos Katsoulakis

We propose a new sensitivity analysis methodology for complex stochastic dynamics based on the relative entropy rate. The method becomes computationally feasible at the stationary regime of the process and involves the calculation of suitable observables in path space for the relative entropy rate and the corresponding Fisher information matrix. The stationary regime is crucial for stochastic dynamics and here allows us to address the sensitivity analysis of complex systems, including examples of processes with complex landscapes that exhibit metastability, non-reversible systems from a statistical mechanics perspective, and high-dimensional, spatially distributed models. All these systems exhibit, typically non-Gaussian stationary probability ...


A Discriminative Hierarchical Model For Fast Coreference At Large Scale, Michael Wick, Sameer Singh, Andrew McCallum 2011 University of Massachusetts - Amherst

A Discriminative Hierarchical Model For Fast Coreference At Large Scale, Michael Wick, Sameer Singh, Andrew Mccallum

Andrew McCallum

Methods that measure compatibility between mention pairs are currently the dominant approach to coreference. However, they suffer from a number of drawbacks including difficulties scaling to large numbers of mentions and limited representational power. As the severity of these drawbacks continue to progress with the growing demand for more data, the need to replace the pairwise approaches with a more expressive, highly scalable alternative is becoming increasingly urgent. In this paper we propose a novel discriminative hierarchical model that recursively structures entities into trees. These trees succinctly summarize the mentions providing a highly-compact information-rich structure for reasoning about entities and ...


Maa*: A Heuristic Search Algorithm For Solving Decentralized Pomdps, Daniel Szer, Francois Charpillet, Shlomo Zilberstein 2011 University of Massachusetts - Amherst

Maa*: A Heuristic Search Algorithm For Solving Decentralized Pomdps, Daniel Szer, Francois Charpillet, Shlomo Zilberstein

Shlomo Zilberstein

We present multi-agent A* (MAA*), the first complete and optimal heuristic search algorithm for solving decentralized partially-observable Markov decision problems (DEC- POMDPs) with finite horizon. The algorithm is suitable for computing optimal plans for a cooperative group of agents that operate in a stochastic environment such as multi-robot coordination, network traffic control, or distributed resource allocation. Solving such problems effectively is a major challenge in the area of planning under uncertainty. Our solution is based on a synthesis of classical heuristic search and decentralized control theory. Experimental results show that MAA* has significant advantages. We introduce an anytime variant of ...


Modeling Dependence Using Skew T Copulas: Bayesian Inference And Applications, Michael S. Smith, Quan Gan, Robert Kohn 2011 Melbourne Business School

Modeling Dependence Using Skew T Copulas: Bayesian Inference And Applications, Michael S. Smith, Quan Gan, Robert Kohn

Michael Stanley Smith

[THIS IS AN AUGUST 2010 REVISION THAT REPLACES ALL PREVIOUS VERSIONS.]

We construct a copula from the skew t distribution of Sahu, Dey & Branco (2003). This copula can capture asymmetric and extreme dependence between variables, and is one of the few copulas that can do so and still be used in high dimensions effectively. However, it is difficult to estimate the copula model by maximum likelihood when the multivariate dimension is high, or when some or all of the marginal distributions are discrete-valued, or when the parameters in the marginal distributions and copula are estimated jointly. We therefore propose a ...


Impact Of Illness And Medical Expenditure On Household Consumptions: A Survey In Western China, Shuangge Ma 2011 Yale University

Impact Of Illness And Medical Expenditure On Household Consumptions: A Survey In Western China, Shuangge Ma

Shuangge Ma

No abstract provided.


Unsupervised Joint Alignment And Clustering Using Bayesian Nonparametrics, Marwan Mattar, Allen Hanson, Erik G. Learned-Miller 2011 University of Massachusetts - Amherst

Unsupervised Joint Alignment And Clustering Using Bayesian Nonparametrics, Marwan Mattar, Allen Hanson, Erik G. Learned-Miller

Erik G Learned-Miller

Joint alignment of a collection of functions is the process of independently transforming the func- tions so that they appear more similar to each other. Typically, such unsupervised alignment al- gorithms fail when presented with complex data sets arising from multiple modalities or make re- strictive assumptions about the form of the func- tions or transformations, limiting their general- ity. We present a transformed Bayesian infinite mixture model that can simultaneously align and cluster a data set. Our model and associated learning scheme offer two key advantages: the optimal number of clusters is determined in a data-driven fashion through the ...


On Some 2-Adic Properties Of A Recurrence Involving Stirling Numbers, Tamas Lengyel 2011 Occidental College

On Some 2-Adic Properties Of A Recurrence Involving Stirling Numbers, Tamas Lengyel

Tamas Lengyel

We analyze some 2 adic properties of the sequence defined by the recurrence Z(1) =1; Z(n) = n−1 k=1 S(n, k) Z(k), n ≥ 2, which counts the number of ultra-dissimilarity relations, i.e., ultra-metrics on an n-set. We prove the 2 adic growth property v2 (Z(n) ≥ log 2 n - 1) and present conjectures on the exact values.


Identification Of Gene-Environment Interactions In Cancer Prognosis Studies Using Penalization, Shuangge Ma 2011 Yale University

Identification Of Gene-Environment Interactions In Cancer Prognosis Studies Using Penalization, Shuangge Ma

Shuangge Ma

High-throughput cancer studies have been extensively conducted, searching for genetic risk factors independently associated with prognosis beyond clinical and environmental risk factors. Many studies have shown that the gene-environment interactions may have important implications. Some of the existing methods, such as the commonly adopted single-marker analysis, may be limited in that they cannot accommodate the joint effects of a large number of genetic markers or use ineffective marker identification techniques. In this study, we analyze cancer prognosis studies, and adopt the AFT (accelerated failure time) model to describe survival. A weighted least squares approach, which has the lowest computational cost ...


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