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176,352 full-text articles. Page 4551 of 4555.

Sustainable Agriculture Bibliography, Matt Bogard 2009 Western Kentucky University

Sustainable Agriculture Bibliography, Matt Bogard

Matt Bogard

An annotated bibliography related to the sustainability of biotechnology and pharmaceutical technologies used in modern agriculture.


Information Cost Tradeoffs For Augmented Index And Streaming Language Recognition, Amit Chakrabarti, Graham Cormode, Ranganath Kondapally, Andrew McGregor 2009 University of Massachusetts - Amherst

Information Cost Tradeoffs For Augmented Index And Streaming Language Recognition, Amit Chakrabarti, Graham Cormode, Ranganath Kondapally, Andrew Mcgregor

Andrew McGregor

This paper makes three main contributions to the theory of communication complexity and stream computation. First, we present new bounds on the information complexity of AUGMENTED-INDEX. In contrast to analogous results for INDEX by Jain, Radhakrishnan and Sen [J. ACM, 2009], we have to overcome the significant technical challenge that protocols for AUGMENTED-INDEX may violate the “rectangle property” due to the inherent input sharing. Second, we use these bounds to resolve an open problem of Magniez, Mathieu and Nayak [STOC, 2010] that asked about the multi-pass complexity of recognizing Dyck languages. This results in a natural separation between the standard ...


The Genomics Education Partnership: Successful Integration Of Research Into Laboratory Classes At A Diverse Group Of Undergraduate Institutions, Elizabeth Shoop, et al 2009 Macalester College

The Genomics Education Partnership: Successful Integration Of Research Into Laboratory Classes At A Diverse Group Of Undergraduate Institutions, Elizabeth Shoop, Et Al

Elizabeth Shoop

No abstract provided.


Optimizing Semantic Coherence In Topic Models, D. Mimno, H. Wallach, E. Talley, M. Leenders, Andrew McCallum 2009 University of Massachusetts - Amherst

Optimizing Semantic Coherence In Topic Models, D. Mimno, H. Wallach, E. Talley, M. Leenders, Andrew Mccallum

Andrew McCallum

Large organizations often face the critical challenge of sharing information and maintaining connections between disparate subunits. Tools for automated analysis of document collections, such as topic models, can provide an important means for communication. The value of topic modeling is in its ability to discover interpretable, coherent themes from unstructured document sets, yet it is not unusual to find semantic mismatches that substantially reduce user confidence. In this paper, we first present an expert-driven topic annotation study, undertaken in order to obtain an annotated set of baseline topics and their distinguishing characteristics. We then present a metric for detecting poor-quality ...


Anhang: Auszüge Aus Dem Späteren Leben Von Professor Dr. Otto Vogl, Otto Vogl 2009 University of Massachusetts - Amherst

Anhang: Auszüge Aus Dem Späteren Leben Von Professor Dr. Otto Vogl, Otto Vogl

Otto Vogl

No abstract provided.


Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin McCollum 2009 Portland State University

Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin Mccollum

Gin McCollum

Human off-vertical axis rotation (OVAR) in the dark typically produces perceived motion about a cone, the amplitude of which changes as a function of frequency. This perception is commonly attributed to the fact that both OVAR and the conical motion have a gravity vector that rotates about the subject. Little-known, however, is that this rotating-gravity explanation for perceived conical motion is inconsistent with basic observations about self-motion perception: (a) that the perceived vertical moves toward alignment with the gravitoinertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA not ...


Gibbs Sampling For A Bayesian Hierarchical General Linear Model, Alicia A. Johnson, Galin L. Jones 2009 University of Minnesota - Twin Cities

Gibbs Sampling For A Bayesian Hierarchical General Linear Model, Alicia A. Johnson, Galin L. Jones

Alicia A. Johnson

No abstract provided.


Spectroscopic Confirmation Of Two Lyman Break Galaxies At Redshift Beyond 7, E. Vanzella, L. Pentericci, A. Fontana, A. Grazian, M. Castellano, K. Boutsia, S. Cristiani, M. Dickinson, S. Gallozzi, E. Giallongo, Mauro Giavalisco, R. Maiolino, A. Moorwood, D. Paris, P. Santini 2009 University of Massachusetts - Amherst

Spectroscopic Confirmation Of Two Lyman Break Galaxies At Redshift Beyond 7, E. Vanzella, L. Pentericci, A. Fontana, A. Grazian, M. Castellano, K. Boutsia, S. Cristiani, M. Dickinson, S. Gallozzi, E. Giallongo, Mauro Giavalisco, R. Maiolino, A. Moorwood, D. Paris, P. Santini

Mauro Giavalisco

We report the spectroscopic confirmation of two Lyman break galaxies at redshift > 7. The galaxies were observed as part of an ultra-deep spectroscopic campaign with FORS2 at the ESO/VLT for the confirmation of z~7 ``z--band dropout'' candidates selected from our VLT/Hawk-I imaging survey. Both galaxies show a prominent emission line at 9735A and 9858A respectively: the lines have fluxes of ~ 1.6-1.2 x 10^(-17) erg/s/cm2 and exhibit a sharp decline on the blue side and a tail on the red side. The asymmetry is quantitatively comparable to the observed asymmetry in z ~ 6 ...


Traveling Wave Solutions For A Nonlocal Reaction-Diffusion Model Of Influenza A Drift, Joaquin Riviera, Yi Li 2009 Wright State University - Main Campus

Traveling Wave Solutions For A Nonlocal Reaction-Diffusion Model Of Influenza A Drift, Joaquin Riviera, Yi Li

Yi Li

In this paper we discuss the existence of traveling wave solutions for a nonlocal reaction-diffusion model of Influenza A proposed in Lin et. al. (2003). The proof for the existence of the traveling wave takes advantage of the different time scales between the evolution of the disease and the progress of the disease in the population. Under this framework we are able to use the techniques from geometric singular perturbation theory to prove the existence of the traveling wave.


Science Drivers And Requirements For An Advanced Technology Large Aperture Space Telescope (Atlast): Implications For Technology Development And Synergies With Other Future Facilities, Marc Postman, Tom Brown, Kenneth Sembach, Mauro Giavalisco, Wesley Traub, Karl Stapelfeldt, Daniela Calzetti, William Oegerle, R. Michael Rich, Phillip Stahl, Jason Tumlinson, Matt Mountain, Rémi Soummer, Tupper Hyde 2009 University of Massachusetts - Amherst

Science Drivers And Requirements For An Advanced Technology Large Aperture Space Telescope (Atlast): Implications For Technology Development And Synergies With Other Future Facilities, Marc Postman, Tom Brown, Kenneth Sembach, Mauro Giavalisco, Wesley Traub, Karl Stapelfeldt, Daniela Calzetti, William Oegerle, R. Michael Rich, Phillip Stahl, Jason Tumlinson, Matt Mountain, Rémi Soummer, Tupper Hyde

Mauro Giavalisco

The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8-meter to 16-meter UVOIR space observatory for launch in the 2025-2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astronphysics, including "Is there life elsewhere in the Galaxy?" We present a range of science drivers that define the main performance requirements for ATLAST (8 to 16 milliarcsec angular resolution, diffraction limited imaging at 0.5 {\mu}m wavelength, minimum collecting area of 45 square meters, high sensitivity to light wavelengths from 0.1 {\mu}m to 2.4 {\mu}m, high stability ...


Resource-Bounded Information Extraction: Acquiring Missing Feature Values On Demand, Pallika Kanani, Andrew McCallum, Shaohan Hu 2009 University of Massachusetts - Amherst

Resource-Bounded Information Extraction: Acquiring Missing Feature Values On Demand, Pallika Kanani, Andrew Mccallum, Shaohan Hu

Andrew McCallum

We present a general framework for the task of extracting specific information ``on demand'' from a large corpus such as the Web under resource-constraints. Given a database with missing or uncertain information, the proposed system automatically formulates queries, issues them to a search interface, selects a subset of the documents, extracts the required information from them, and fills the missing values in the original database. We also exploit inherent dependency within the data to obtain useful information with fewer computational resources. We build such a system in the citation database domain that extracts the missing publication years using limited resources ...


Rollout Sampling Policy Iteration For Decentralized Pomdps, Feng Wu, Shlomo Zilberstein, Xiaoping Chen 2009 University of Massachusetts - Amherst

Rollout Sampling Policy Iteration For Decentralized Pomdps, Feng Wu, Shlomo Zilberstein, Xiaoping Chen

Shlomo Zilberstein

We present decentralized rollout sampling policy iteration (DecRSPI)--a new algorithm for multiagent decision problems formalized as DEC-POMDPs. DecRSPI is designed to improve scalability and tackle problems that lack an explicit model. The algorithm uses Monte-Carlo methods to generate a sample of reachable belief states. Then it computes a joint policy for each belief state based on the rollout estimations. A new policy representation allows us to represent solutions compactly. The key benefits of the algorithm are its linear time complexity over the number of agents, its bounded memory usage and good solution quality. It can solve larger problems that ...


Symmetries Of The Central Vestibular System: Forming Movements For Gravity And A Three-Dimensional World, Gin McCollum, Douglas A. Hanes 2009 Portland State University

Symmetries Of The Central Vestibular System: Forming Movements For Gravity And A Three-Dimensional World, Gin Mccollum, Douglas A. Hanes

Gin McCollum

Intrinsic dynamics of the central vestibular system (CVS) appear to be at least partly determined by the symmetries of its connections. The CVS contributes to whole-body functions such as upright balance and maintenance of gaze direction. These functions coordinate disparate senses (visual, inertial, somatosensory, auditory) and body movements (leg, trunk, head/neck, eye). They are also unified by geometric conditions. Symmetry groups have been found to structure experimentally-recorded pathways of the central vestibular system. When related to geometric conditions in three-dimensional physical space, these symmetry groups make sense as a logical foundation for sensorimotor coordination.


Improving State-Of-The-Art Ocr Through High-Precision Document-Specific Modeling, Andrew Kae, Gary B. Huang, Carl Doersch, Erik G. Learned-Miller 2009 University of Massachusetts - Amherst

Improving State-Of-The-Art Ocr Through High-Precision Document-Specific Modeling, Andrew Kae, Gary B. Huang, Carl Doersch, Erik G. Learned-Miller

Erik G Learned-Miller

Optical character recognition (OCR) remains a difficult problem for noisy documents or documents not scanned at high resolution. Many current approaches rely on stored font models that are vulnerable to cases in which the docu- ment is noisy or is written in a font dissimilar to the stored fonts. We address these problems by learning character models directly from the document itself, rather than using pre-stored font models. This method has had some success in the past, but we are able to achieve substantial improve- ment in error reduction through a novel method for creating nearly error-free document-specifictraining data and ...


Constructing Skill Trees For Reinforcement Learning Agents From Demonstration Trajectories, George Konidaris, Scott Kuindersma, Andrew Barto, Roderic Grupen 2009 University of Massachusetts - Amherst

Constructing Skill Trees For Reinforcement Learning Agents From Demonstration Trajectories, George Konidaris, Scott Kuindersma, Andrew Barto, Roderic Grupen

Roderic Grupen

We introduce CST, an algorithm for constructing skill trees from demonstration trajectories in continuous reinforcement learning domains. CST uses a change-point detection method to segment each trajectory into a skill chain by detecting a change of appropriate abstraction, or that a segment is too complex to model as a single skill. The skill chains from each trajectory are then merged to form a skill tree. We demonstrate that CST constructs an appropriate skill tree that can be further refined through learning in a challenging continuous domain, and that it can be used to segment demonstration trajectories on a mobile manipulator ...


A Closer Look At The Relative Age Effect In The National Hockey League, Vittorio Addona, P. A. Yates 2009 Macalester College

A Closer Look At The Relative Age Effect In The National Hockey League, Vittorio Addona, P. A. Yates

Vittorio Addona

No abstract provided.


Learning From A Single Demonstration: Motion Planning With Skill Segmentation, Scott Kuindersma, George Konidaris, Roderic Grupen, Andrew Barto 2009 University of Massachusetts - Amherst

Learning From A Single Demonstration: Motion Planning With Skill Segmentation, Scott Kuindersma, George Konidaris, Roderic Grupen, Andrew Barto

Roderic Grupen

We propose an approach to control learning from demonstration that first segments demonstration trajectories to identify subgoals to solve the overall task. Using this approach, we show that a mobile robot is able to solve a combined navigation and manipulation task robustly after observing only a single successful trajectory.


The 1905 Einstein Equation In A General Mathematical Analysis Model Of Quasars, Byron E. Bell 2009 DePaul University and Columbia College Chicago

The 1905 Einstein Equation In A General Mathematical Analysis Model Of Quasars, Byron E. Bell

Byron E. Bell

No abstract provided.


Gis @ Ut Libraries, Allison Roberts 2009 University of Tennessee - Knoxville

Gis @ Ut Libraries, Allison Roberts

Allison Roberts

Information handout/poster for GIS services at UT


Joint Feature Selection And Classification For Taxonomic Problems Within Fish Species Complexes, Yixin Chen, Shuqing Huang, Huimin Chen, Henry L. Bart 2009 University of Mississippi

Joint Feature Selection And Classification For Taxonomic Problems Within Fish Species Complexes, Yixin Chen, Shuqing Huang, Huimin Chen, Henry L. Bart

Huimin Chen

It is estimated that 90% of the world’s species are yet to be discovered and described. The main reason for the slow pace of new species description is that the science of taxonomy can be very laborious. To formally describe a new species, taxonomists have to manually gather and analyze data from large numbers of specimens and identify the smallest subset of external body characters that uniquely diagnose the new species as distinct from all its known relatives. In this paper, we present an automated feature selection and classification scheme using logistic regression with controlled false discovery rate to ...


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