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Cortical Underconnectivity Coupled With Preserved Visuospatial Cognition In Autism: Evidence From An Fmri Study Of An Embedded Figures Task, Saudamini Damarla, Timothy A. Keller, Rajesh K. Kana, Vladimir L. Cherkassky, Diane L. Williams, Nancy J. Minshew, Marcel Adam Just 2009 Carnegie Mellon University

Cortical Underconnectivity Coupled With Preserved Visuospatial Cognition In Autism: Evidence From An Fmri Study Of An Embedded Figures Task, Saudamini Damarla, Timothy A. Keller, Rajesh K. Kana, Vladimir L. Cherkassky, Diane L. Williams, Nancy J. Minshew, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Bent-Core Liquid Crystal Elastomers, Rafael Verduzco, Paul Luchette, Seung Ho Hong, John Harden, Elaine DiMasi, Peter Palffy-Muhoray, S. Michael Kilbey II, Jim T. Gleeson, Antal Jákli 2009 Kent State University - Kent Campus

Bent-Core Liquid Crystal Elastomers, Rafael Verduzco, Paul Luchette, Seung Ho Hong, John Harden, Elaine Dimasi, Peter Palffy-Muhoray, S. Michael Kilbey Ii, Jim T. Gleeson, Antal Jákli

Peter Palffy-Muhoray

Liquid crystal (LC) elastomers with bent-core side-groups incorporate the properties of bent-core liquid crystals in a flexible and self-supporting polymer network. Bent-core liquid crystal elastomers (BCEs) with uniform alignment were prepared by attaching a reactive bent-core LC to poly(hydrogenmethylsiloxane) and crosslinking with a divinyl crosslinker. Phase behavior studies indicate a nematic phase over a wide temperature range that approaches room temperature, and thermoelastic measurements show that these BCEs can reversibly change their length by more than a factor of two upon heating and cooling. Small-angle X-ray scattering studies reveal multiple, broad low-angle peaks consistent with short-range smectic C order ...


Nearest Neighbor Based Collection Ocr, Pramod Sankar K., C. V. Jawahar, R. Manmatha 2009 University of Massachusetts - Amherst

Nearest Neighbor Based Collection Ocr, Pramod Sankar K., C. V. Jawahar, R. Manmatha

R. Manmatha

Conventional optical character recognition (OCR) systems operate on individual characters and words, and do not normally exploit document or collection context. We describe a Collection OCR which takes advantage of the fact that multiple examples of the same word (often in the same font) may occur in a document or collection. The idea here is that an OCR or a reCAPTCHA like process generates a partial set of recognized words. In the second stage, a nearest neighbor algorithm compares the remaining word-images to those already recognized and propagates labels from the nearest neighbors. It is shown that by using an ...


Population Annealing With Weighted Averages: A Monte Carlo Method For Rough Free-Energy Landscapes, Jonathan Machta 2009 University of Massachusetts Amherst

Population Annealing With Weighted Averages: A Monte Carlo Method For Rough Free-Energy Landscapes, Jonathan Machta

Jonathan Machta

The population annealing algorithm introduced by Hukushima and Iba is described. Population annealing combines simulated annealing and Boltzmann weighted differential reproduction within a population of replicas to sample equilibrium states. Population annealing gives direct access to the free energy. It is shown that unbiased measurements of observables can be obtained by weighted averages over many runs with weight factors related to the free-energy estimate from the run. Population annealing is well suited to parallelization and may be a useful alternative to parallel tempering for systems with rough free-energy landscapes such as spin glasses. The method is demonstrated for spin glasses.


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 the 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 gravito-inertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA ...


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

Andrew Kae

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 ...


Determining Rates Of Virus Production In Aquatic Systems By The Virus Reduction Approach,, M.G. Weinbauer, J.M. Rowe, Steven Wilhelm 2009 University of Tennessee, Knoxville

Determining Rates Of Virus Production In Aquatic Systems By The Virus Reduction Approach,, M.G. Weinbauer, J.M. Rowe, Steven Wilhelm

Steven Wilhelm

The reduction approach to assess virus production and the prokaryotic mortality by viral lysis stops new infection by reducing total virus abundance (and thus virus–host contacts). This allows for easy enumeration of viruses that originate from lysis of already infected cells due to the decreased abundance of free virus particles. This reoccurrence can be quantified and used to assess production and cell lysis rates. Several modifications of the method are presented and compared. The approaches have great potential for elucidating trends in virus production rates as well as for making generalized estimates of the quantitative effects of viruses on ...


Asymptotic Behavior Of The Finite-Size Magnetization As A Function Of The Speed Of Approach To Criticality, Richard S. Ellis, Jonathan Machta, Peter Tak-Hun Otto 2009 University of Massachusetts - Amherst

Asymptotic Behavior Of The Finite-Size Magnetization As A Function Of The Speed Of Approach To Criticality, Richard S. Ellis, Jonathan Machta, Peter Tak-Hun Otto

Richard S. Ellis

The main focus of this paper is to determine whether the thermodynamic magnetization is a physically relevant estimator of the finite-size magnetization. This is done by comparing the asymptotic behaviors of these two quantities along parameter sequences converging to either a second-order point or the tricritical point in the mean-field Blume–Capel model. We show that the thermodynamic magnetization and the finite-size magnetization are asymptotic when the parameter α governing the speed at which the sequence approaches criticality is below a certain threshold α0. However, when α exceeds α0, the thermodynamic magnetization converges to 0 much faster than the finite-size ...


Binary Tidal Disruption Radius, Eric Addison 2009 Utah State University

Binary Tidal Disruption Radius, Eric Addison

Eric Addison

An expression for the tidal disruption radius of a binary system is calculated.


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.


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.


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.


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