Frontopolar cortex mediates abstract integration in analogy.

Science.gov (United States)

Green, Adam E; Fugelsang, Jonathan A; Kraemer, David J M; Shamosh, Noah A; Dunbar, Kevin N

2006-06-22

Integration of abstractly similar relations during analogical reasoning was investigated using functional magnetic resonance imaging. Activation elicited by an analogical reasoning task that required both complex working memory and integration of abstractly similar relations was compared to activation elicited by a non-analogical task that required complex working memory in the absence of abstract relational integration. A left-sided region of the frontal pole of the brain (BA 9/10) was selectively active for the abstract relational integration component of analogical reasoning. Analogical reasoning also engaged a left-sided network of parieto-frontal regions. Activity in this network during analogical reasoning is hypothesized to reflect categorical alignment of individual component terms that make up analogies. This parieto-frontal network was also engaged by the complex control task, which involved explicit categorization, but not by a simpler control task, which did not involve categorization. We hypothesize that frontopolar cortex mediates abstract relational integration in complex reasoning while parieto-frontal regions mediate working memory processes, including manipulation of terms for the purpose of categorical alignment, that facilitate this integration.

Regularity effect in prospective memory during aging

Directory of Open Access Journals (Sweden)

Geoffrey Blondelle

2016-10-01

Full Text Available Background: Regularity effect can affect performance in prospective memory (PM, but little is known on the cognitive processes linked to this effect. Moreover, its impacts with regard to aging remain unknown. To our knowledge, this study is the first to examine regularity effect in PM in a lifespan perspective, with a sample of young, intermediate, and older adults. Objective and design: Our study examined the regularity effect in PM in three groups of participants: 28 young adults (18–30, 16 intermediate adults (40–55, and 25 older adults (65–80. The task, adapted from the Virtual Week, was designed to manipulate the regularity of the various activities of daily life that were to be recalled (regular repeated activities vs. irregular non-repeated activities. We examine the role of several cognitive functions including certain dimensions of executive functions (planning, inhibition, shifting, and binding, short-term memory, and retrospective episodic memory to identify those involved in PM, according to regularity and age. Results: A mixed-design ANOVA showed a main effect of task regularity and an interaction between age and regularity: an age-related difference in PM performances was found for irregular activities (older < young, but not for regular activities. All participants recalled more regular activities than irregular ones with no age effect. It appeared that recalling of regular activities only involved planning for both intermediate and older adults, while recalling of irregular ones were linked to planning, inhibition, short-term memory, binding, and retrospective episodic memory. Conclusion: Taken together, our data suggest that planning capacities seem to play a major role in remembering to perform intended actions with advancing age. Furthermore, the age-PM-paradox may be attenuated when the experimental design is adapted by implementing a familiar context through the use of activities of daily living. The clinical

Regularized maximum correntropy machine

KAUST Repository

Wang, Jim Jing-Yan; Wang, Yunji; Jing, Bing-Yi; Gao, Xin

2015-01-01

In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

Regularized maximum correntropy machine

KAUST Repository

Wang, Jim Jing-Yan

2015-02-12

In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

Visual mismatch negativity indicates automatic, task-independent detection of artistic image composition in abstract artworks.

Science.gov (United States)

Menzel, Claudia; Kovács, Gyula; Amado, Catarina; Hayn-Leichsenring, Gregor U; Redies, Christoph

2018-05-06

In complex abstract art, image composition (i.e., the artist's deliberate arrangement of pictorial elements) is an important aesthetic feature. We investigated whether the human brain detects image composition in abstract artworks automatically (i.e., independently of the experimental task). To this aim, we studied whether a group of 20 original artworks elicited a visual mismatch negativity when contrasted with a group of 20 images that were composed of the same pictorial elements as the originals, but in shuffled arrangements, which destroy artistic composition. We used a passive oddball paradigm with parallel electroencephalogram recordings to investigate the detection of image type-specific properties. We observed significant deviant-standard differences for the shuffled and original images, respectively. Furthermore, for both types of images, differences in amplitudes correlated with the behavioral ratings of the images. In conclusion, we show that the human brain can detect composition-related image properties in visual artworks in an automatic fashion. Copyright © 2018 Elsevier B.V. All rights reserved.

Semantic Neighborhood Effects for Abstract versus Concrete Words.

Science.gov (United States)

Danguecan, Ashley N; Buchanan, Lori

2016-01-01

Studies show that semantic effects may be task-specific, and thus, that semantic representations are flexible and dynamic. Such findings are critical to the development of a comprehensive theory of semantic processing in visual word recognition, which should arguably account for how semantic effects may vary by task. It has been suggested that semantic effects are more directly examined using tasks that explicitly require meaning processing relative to those for which meaning processing is not necessary (e.g., lexical decision task). The purpose of the present study was to chart the processing of concrete versus abstract words in the context of a global co-occurrence variable, semantic neighborhood density (SND), by comparing word recognition response times (RTs) across four tasks varying in explicit semantic demands: standard lexical decision task (with non-pronounceable non-words), go/no-go lexical decision task (with pronounceable non-words), progressive demasking task, and sentence relatedness task. The same experimental stimulus set was used across experiments and consisted of 44 concrete and 44 abstract words, with half of these being low SND, and half being high SND. In this way, concreteness and SND were manipulated in a factorial design using a number of visual word recognition tasks. A consistent RT pattern emerged across tasks, in which SND effects were found for abstract (but not necessarily concrete) words. Ultimately, these findings highlight the importance of studying interactive effects in word recognition, and suggest that linguistic associative information is particularly important for abstract words.

Task-relevant information is prioritized in spatiotemporal contextual cueing.

Science.gov (United States)

Higuchi, Yoko; Ueda, Yoshiyuki; Ogawa, Hirokazu; Saiki, Jun

2016-11-01

Implicit learning of visual contexts facilitates search performance-a phenomenon known as contextual cueing; however, little is known about contextual cueing under situations in which multidimensional regularities exist simultaneously. In everyday vision, different information, such as object identity and location, appears simultaneously and interacts with each other. We tested the hypothesis that, in contextual cueing, when multiple regularities are present, the regularities that are most relevant to our behavioral goals would be prioritized. Previous studies of contextual cueing have commonly used the visual search paradigm. However, this paradigm is not suitable for directing participants' attention to a particular regularity. Therefore, we developed a new paradigm, the "spatiotemporal contextual cueing paradigm," and manipulated task-relevant and task-irrelevant regularities. In four experiments, we demonstrated that task-relevant regularities were more responsible for search facilitation than task-irrelevant regularities. This finding suggests our visual behavior is focused on regularities that are relevant to our current goal.

From mind to matter: neural correlates of abstract and concrete mindsets

Science.gov (United States)

Liberman, Nira; Maril, Anat

2014-01-01

Much work in the field of social cognition shows that adopting an abstract (vs concrete) mindset alters the way people construe the world, thereby exerting substantial effects across innumerable aspects of human behavior. In order to investigate the cognitive and neural basis of these effects, we scanned participants as they performed two widely used tasks that induce an abstracting vs concretizing mindsets. Specifically, participants: (i) indicated ‘why’ perform certain activities (a task that involves abstraction) or ‘how’ the same activities are performed (a task that involves concretization) and (ii) generated superordinate categories for certain objects (a task that involves abstraction) or subordinate exemplars for the same objects (a task that involves concretization). We conducted a conjunction analysis of the two tasks, in order to uncover the neural activity associated with abstraction and concretization. The results showed that concretization was associated with activation in fronto-parietal regions implicated in goal-directed action; abstraction was associated with activity within posterior regions implicated in visual perception. We discuss these findings in light of construal-level theory’s notion of abstraction. PMID:23482624

Manifold regularized multitask learning for semi-supervised multilabel image classification.

Science.gov (United States)

Luo, Yong; Tao, Dacheng; Geng, Bo; Xu, Chao; Maybank, Stephen J

2013-02-01

It is a significant challenge to classify images with multiple labels by using only a small number of labeled samples. One option is to learn a binary classifier for each label and use manifold regularization to improve the classification performance by exploring the underlying geometric structure of the data distribution. However, such an approach does not perform well in practice when images from multiple concepts are represented by high-dimensional visual features. Thus, manifold regularization is insufficient to control the model complexity. In this paper, we propose a manifold regularized multitask learning (MRMTL) algorithm. MRMTL learns a discriminative subspace shared by multiple classification tasks by exploiting the common structure of these tasks. It effectively controls the model complexity because different tasks limit one another's search volume, and the manifold regularization ensures that the functions in the shared hypothesis space are smooth along the data manifold. We conduct extensive experiments, on the PASCAL VOC'07 dataset with 20 classes and the MIR dataset with 38 classes, by comparing MRMTL with popular image classification algorithms. The results suggest that MRMTL is effective for image classification.

Manifold Regularized Reinforcement Learning.

Science.gov (United States)

Li, Hongliang; Liu, Derong; Wang, Ding

2018-04-01

This paper introduces a novel manifold regularized reinforcement learning scheme for continuous Markov decision processes. Smooth feature representations for value function approximation can be automatically learned using the unsupervised manifold regularization method. The learned features are data-driven, and can be adapted to the geometry of the state space. Furthermore, the scheme provides a direct basis representation extension for novel samples during policy learning and control. The performance of the proposed scheme is evaluated on two benchmark control tasks, i.e., the inverted pendulum and the energy storage problem. Simulation results illustrate the concepts of the proposed scheme and show that it can obtain excellent performance.

Abstract Cauchy problems three approaches

CERN Document Server

Melnikova, Irina V

2001-01-01

Although the theory of well-posed Cauchy problems is reasonably understood, ill-posed problems-involved in a numerous mathematical models in physics, engineering, and finance- can be approached in a variety of ways. Historically, there have been three major strategies for dealing with such problems: semigroup, abstract distribution, and regularization methods. Semigroup and distribution methods restore well-posedness, in a modern weak sense. Regularization methods provide approximate solutions to ill-posed problems. Although these approaches were extensively developed over the last decades by many researchers, nowhere could one find a comprehensive treatment of all three approaches.Abstract Cauchy Problems: Three Approaches provides an innovative, self-contained account of these methods and, furthermore, demonstrates and studies some of the profound connections between them. The authors discuss the application of different methods not only to the Cauchy problem that is not well-posed in the classical sense, b...

HIERARCHICAL REGULARIZATION OF POLYGONS FOR PHOTOGRAMMETRIC POINT CLOUDS OF OBLIQUE IMAGES

Directory of Open Access Journals (Sweden)

L. Xie

2017-05-01

Full Text Available Despite the success of multi-view stereo (MVS reconstruction from massive oblique images in city scale, only point clouds and triangulated meshes are available from existing MVS pipelines, which are topologically defect laden, free of semantical information and hard to edit and manipulate interactively in further applications. On the other hand, 2D polygons and polygonal models are still the industrial standard. However, extraction of the 2D polygons from MVS point clouds is still a non-trivial task, given the fact that the boundaries of the detected planes are zigzagged and regularities, such as parallel and orthogonal, cannot preserve. Aiming to solve these issues, this paper proposes a hierarchical polygon regularization method for the photogrammetric point clouds from existing MVS pipelines, which comprises of local and global levels. After boundary points extraction, e.g. using alpha shapes, the local level is used to consolidate the original points, by refining the orientation and position of the points using linear priors. The points are then grouped into local segments by forward searching. In the global level, regularities are enforced through a labeling process, which encourage the segments share the same label and the same label represents segments are parallel or orthogonal. This is formulated as Markov Random Field and solved efficiently. Preliminary results are made with point clouds from aerial oblique images and compared with two classical regularization methods, which have revealed that the proposed method are more powerful in abstracting a single building and is promising for further 3D polygonal model reconstruction and GIS applications.

Prior knowledge regularization in statistical medical image tasks

DEFF Research Database (Denmark)

Crimi, Alessandro; Sporring, Jon; de Bruijne, Marleen

2009-01-01

The estimation of the covariance matrix is a pivotal step inseveral statistical tasks. In particular, the estimation becomes challeng-ing for high dimensional representations of data when few samples areavailable. Using the standard Maximum Likelihood estimation (MLE)when the number of samples ar...

Embedded interruptions and task complexity influence schema-related cognitive load progression in an abstract learning task.

Science.gov (United States)

Wirzberger, Maria; Esmaeili Bijarsari, Shirin; Rey, Günter Daniel

2017-09-01

Cognitive processes related to schema acquisition comprise an essential source of demands in learning situations. Since the related amount of cognitive load is supposed to change over time, plausible temporal models of load progression based on different theoretical backgrounds are inspected in this study. A total of 116 student participants completed a basal symbol sequence learning task, which provided insights into underlying cognitive dynamics. Two levels of task complexity were determined by the amount of elements within the symbol sequence. In addition, interruptions due to an embedded secondary task occurred at five predefined stages over the task. Within the resulting 2x5-factorial mixed between-within design, the continuous monitoring of efficiency in learning performance enabled assumptions on relevant resource investment. From the obtained results, a nonlinear change of learning efficiency over time seems most plausible in terms of cognitive load progression. Moreover, different effects of the induced interruptions show up in conditions of task complexity, which indicate the activation of distinct cognitive mechanisms related to structural aspects of the task. Findings are discussed in the light of evidence from research on memory and information processing. Copyright © 2017 Elsevier B.V. All rights reserved.

Impulsivity and related neuropsychological features in regular and addictive first person shooter gaming.

Science.gov (United States)

Metcalf, Olivia; Pammer, Kristen

2014-03-01

Putative cyber addictions are of significant interest. There remains little experimental research into excessive use of first person shooter (FPS) games, despite their global popularity. Moreover, the role between excessive gaming and impulsivity remains unclear, with previous research showing conflicting findings. The current study investigated performances on a number of neuropsychological tasks (go/no-go, continuous performance task, Iowa gambling task) and a trait measure of impulsivity for a group of regular FPS gamers (n=25), addicted FPS gamers (n=22), and controls (n=22). Gamers were classified using the Addiction-Engagement Questionnaire. Addicted FPS gamers had significantly higher levels of trait impulsivity on the Barratt Impulsiveness Scale compared to controls. Addicted FPS gamers also had significantly higher levels of disinhibition in a go/no-go task and inattention in a continuous performance task compared to controls, whereas the regular FPS gamers had better decision making on the Iowa gambling task compared to controls. The results indicate impulsivity is associated with FPS gaming addiction, comparable to pathological gambling. The relationship between impulsivity and excessive gaming may be unique to the FPS genre. Furthermore, regular FPS gaming may improve decision making ability.

Progressive image denoising through hybrid graph Laplacian regularization: a unified framework.

Science.gov (United States)

Liu, Xianming; Zhai, Deming; Zhao, Debin; Zhai, Guangtao; Gao, Wen

2014-04-01

Recovering images from corrupted observations is necessary for many real-world applications. In this paper, we propose a unified framework to perform progressive image recovery based on hybrid graph Laplacian regularized regression. We first construct a multiscale representation of the target image by Laplacian pyramid, then progressively recover the degraded image in the scale space from coarse to fine so that the sharp edges and texture can be eventually recovered. On one hand, within each scale, a graph Laplacian regularization model represented by implicit kernel is learned, which simultaneously minimizes the least square error on the measured samples and preserves the geometrical structure of the image data space. In this procedure, the intrinsic manifold structure is explicitly considered using both measured and unmeasured samples, and the nonlocal self-similarity property is utilized as a fruitful resource for abstracting a priori knowledge of the images. On the other hand, between two successive scales, the proposed model is extended to a projected high-dimensional feature space through explicit kernel mapping to describe the interscale correlation, in which the local structure regularity is learned and propagated from coarser to finer scales. In this way, the proposed algorithm gradually recovers more and more image details and edges, which could not been recovered in previous scale. We test our algorithm on one typical image recovery task: impulse noise removal. Experimental results on benchmark test images demonstrate that the proposed method achieves better performance than state-of-the-art algorithms.

Stochastic abstract policies: generalizing knowledge to improve reinforcement learning.

Science.gov (United States)

Koga, Marcelo L; Freire, Valdinei; Costa, Anna H R

2015-01-01

Reinforcement learning (RL) enables an agent to learn behavior by acquiring experience through trial-and-error interactions with a dynamic environment. However, knowledge is usually built from scratch and learning to behave may take a long time. Here, we improve the learning performance by leveraging prior knowledge; that is, the learner shows proper behavior from the beginning of a target task, using the knowledge from a set of known, previously solved, source tasks. In this paper, we argue that building stochastic abstract policies that generalize over past experiences is an effective way to provide such improvement and this generalization outperforms the current practice of using a library of policies. We achieve that contributing with a new algorithm, AbsProb-PI-multiple and a framework for transferring knowledge represented as a stochastic abstract policy in new RL tasks. Stochastic abstract policies offer an effective way to encode knowledge because the abstraction they provide not only generalizes solutions but also facilitates extracting the similarities among tasks. We perform experiments in a robotic navigation environment and analyze the agent's behavior throughout the learning process and also assess the transfer ratio for different amounts of source tasks. We compare our method with the transfer of a library of policies, and experiments show that the use of a generalized policy produces better results by more effectively guiding the agent when learning a target task.

The Temporal Dynamics of Regularity Extraction in Non-Human Primates

Science.gov (United States)

Minier, Laure; Fagot, Joël; Rey, Arnaud

2016-01-01

Extracting the regularities of our environment is one of our core cognitive abilities. To study the fine-grained dynamics of the extraction of embedded regularities, a method combining the advantages of the artificial language paradigm (Saffran, Aslin, & Newport, [Saffran, J. R., 1996]) and the serial response time task (Nissen & Bullemer,…

Annotation of regular polysemy and underspecification

DEFF Research Database (Denmark)

Martínez Alonso, Héctor; Pedersen, Bolette Sandford; Bel, Núria

2013-01-01

We present the result of an annotation task on regular polysemy for a series of seman- tic classes or dot types in English, Dan- ish and Spanish. This article describes the annotation process, the results in terms of inter-encoder agreement, and the sense distributions obtained with two methods...

Converting One Type-Based Abstract Domain to Another

DEFF Research Database (Denmark)

Gallagher, John Patrick; Puebla, German; Albert, Elvira

2006-01-01

The specific problem that motivates this paper is how to obtain abstract descriptions of the meanings of imported predicates (such as built-ins) that can be used when analysing a module of a logic program with respect to some abstract domain. We assume that abstract descriptions of the imported....... We develop a method which has been applied in order to generate call and success patterns from the Ciaopp assertions for built-ins, for any given regular type-based domain. In the paper we present the method as an instance of the more general problem of mapping elements of one abstract domain...

Generalized Bregman distances and convergence rates for non-convex regularization methods

International Nuclear Information System (INIS)

Grasmair, Markus

2010-01-01

We generalize the notion of Bregman distance using concepts from abstract convexity in order to derive convergence rates for Tikhonov regularization with non-convex regularization terms. In particular, we study the non-convex regularization of linear operator equations on Hilbert spaces, showing that the conditions required for the application of the convergence rates results are strongly related to the standard range conditions from the convex case. Moreover, we consider the setting of sparse regularization, where we show that a rate of order δ 1/p holds, if the regularization term has a slightly faster growth at zero than |t| p

Multiple graph regularized protein domain ranking.

Science.gov (United States)

Wang, Jim Jing-Yan; Bensmail, Halima; Gao, Xin

2012-11-19

Protein domain ranking is a fundamental task in structural biology. Most protein domain ranking methods rely on the pairwise comparison of protein domains while neglecting the global manifold structure of the protein domain database. Recently, graph regularized ranking that exploits the global structure of the graph defined by the pairwise similarities has been proposed. However, the existing graph regularized ranking methods are very sensitive to the choice of the graph model and parameters, and this remains a difficult problem for most of the protein domain ranking methods. To tackle this problem, we have developed the Multiple Graph regularized Ranking algorithm, MultiG-Rank. Instead of using a single graph to regularize the ranking scores, MultiG-Rank approximates the intrinsic manifold of protein domain distribution by combining multiple initial graphs for the regularization. Graph weights are learned with ranking scores jointly and automatically, by alternately minimizing an objective function in an iterative algorithm. Experimental results on a subset of the ASTRAL SCOP protein domain database demonstrate that MultiG-Rank achieves a better ranking performance than single graph regularized ranking methods and pairwise similarity based ranking methods. The problem of graph model and parameter selection in graph regularized protein domain ranking can be solved effectively by combining multiple graphs. This aspect of generalization introduces a new frontier in applying multiple graphs to solving protein domain ranking applications.

Abstracts: NRC Waste Management Program reports

Energy Technology Data Exchange (ETDEWEB)

Heckman, R.A.; Minichino, C.

1979-11-01

This document consists of abstracts of all reports published by the Nuclear Regulatory Commission (NRC) Waste Management Program at Lawrence Livermore Laboratory (LLL). It will be updated at regular intervals. Reports are arranged in numerical order, within each category. Unless otherwise specified, authors are LLL scientists and engineers.

Abstracts: NRC Waste Management Program reports

International Nuclear Information System (INIS)

Heckman, R.A.; Minichino, C.

1979-11-01

This document consists of abstracts of all reports published by the Nuclear Regulatory Commission (NRC) Waste Management Program at Lawrence Livermore Laboratory (LLL). It will be updated at regular intervals. Reports are arranged in numerical order, within each category. Unless otherwise specified, authors are LLL scientists and engineers

Implicit learning out of the lab: the case of orthographic regularities.

Science.gov (United States)

Pacton, S; Perruchet, P; Fayol, M; Cleeremans, A

2001-09-01

Children's (Grades 1 to 5) implicit learning of French orthographic regularities was investigated through nonword judgment (Experiments 1 and 2) and completion (Experiments 3a and 3b) tasks. Children were increasingly sensitive to (a) the frequency of double consonants (Experiments 1, 2, and 3a), (b) the fact that vowels can never be doubled (Experiment 2), and (c) the legal position of double consonants (Experiments 2 and 3b). The latter effect transferred to never doubled consonants but with a decrement in performance. Moreover, this decrement persisted without any trend toward fading, even after the massive amounts of experience provided by years of practice. This result runs against the idea that transfer to novel material is indicative of abstract rule-based knowledge and suggests instead the action of mechanisms sensitive to the statistical properties of the material. A connectionist model is proposed as an instantiation of such mechanisms.

Analysis of Logic Programs Using Regular Tree Languages

DEFF Research Database (Denmark)

Gallagher, John Patrick

2012-01-01

The eld of nite tree automata provides fundamental notations and tools for reasoning about set of terms called regular or recognizable tree languages. We consider two kinds of analysis using regular tree languages, applied to logic programs. The rst approach is to try to discover automatically...... a tree automaton from a logic program, approximating its minimal Herbrand model. In this case the input for the analysis is a program, and the output is a tree automaton. The second approach is to expose or check properties of the program that can be expressed by a given tree automaton. The input...... to the analysis is a program and a tree automaton, and the output is an abstract model of the program. These two contrasting abstract interpretations can be used in a wide range of analysis and verication problems....

Learning regularization parameters for general-form Tikhonov

International Nuclear Information System (INIS)

Chung, Julianne; Español, Malena I

2017-01-01

Computing regularization parameters for general-form Tikhonov regularization can be an expensive and difficult task, especially if multiple parameters or many solutions need to be computed in real time. In this work, we assume training data is available and describe an efficient learning approach for computing regularization parameters that can be used for a large set of problems. We consider an empirical Bayes risk minimization framework for finding regularization parameters that minimize average errors for the training data. We first extend methods from Chung et al (2011 SIAM J. Sci. Comput. 33 3132–52) to the general-form Tikhonov problem. Then we develop a learning approach for multi-parameter Tikhonov problems, for the case where all involved matrices are simultaneously diagonalizable. For problems where this is not the case, we describe an approach to compute near-optimal regularization parameters by using operator approximations for the original problem. Finally, we propose a new class of regularizing filters, where solutions correspond to multi-parameter Tikhonov solutions, that requires less data than previously proposed optimal error filters, avoids the generalized SVD, and allows flexibility and novelty in the choice of regularization matrices. Numerical results for 1D and 2D examples using different norms on the errors show the effectiveness of our methods. (paper)

Multiple graph regularized protein domain ranking

KAUST Repository

Wang, Jim Jing-Yan

2012-11-19

Background: Protein domain ranking is a fundamental task in structural biology. Most protein domain ranking methods rely on the pairwise comparison of protein domains while neglecting the global manifold structure of the protein domain database. Recently, graph regularized ranking that exploits the global structure of the graph defined by the pairwise similarities has been proposed. However, the existing graph regularized ranking methods are very sensitive to the choice of the graph model and parameters, and this remains a difficult problem for most of the protein domain ranking methods.Results: To tackle this problem, we have developed the Multiple Graph regularized Ranking algorithm, MultiG-Rank. Instead of using a single graph to regularize the ranking scores, MultiG-Rank approximates the intrinsic manifold of protein domain distribution by combining multiple initial graphs for the regularization. Graph weights are learned with ranking scores jointly and automatically, by alternately minimizing an objective function in an iterative algorithm. Experimental results on a subset of the ASTRAL SCOP protein domain database demonstrate that MultiG-Rank achieves a better ranking performance than single graph regularized ranking methods and pairwise similarity based ranking methods.Conclusion: The problem of graph model and parameter selection in graph regularized protein domain ranking can be solved effectively by combining multiple graphs. This aspect of generalization introduces a new frontier in applying multiple graphs to solving protein domain ranking applications. 2012 Wang et al; licensee BioMed Central Ltd.

Multiple graph regularized protein domain ranking

KAUST Repository

Wang, Jim Jing-Yan; Bensmail, Halima; Gao, Xin

2012-01-01

Background: Protein domain ranking is a fundamental task in structural biology. Most protein domain ranking methods rely on the pairwise comparison of protein domains while neglecting the global manifold structure of the protein domain database. Recently, graph regularized ranking that exploits the global structure of the graph defined by the pairwise similarities has been proposed. However, the existing graph regularized ranking methods are very sensitive to the choice of the graph model and parameters, and this remains a difficult problem for most of the protein domain ranking methods.Results: To tackle this problem, we have developed the Multiple Graph regularized Ranking algorithm, MultiG-Rank. Instead of using a single graph to regularize the ranking scores, MultiG-Rank approximates the intrinsic manifold of protein domain distribution by combining multiple initial graphs for the regularization. Graph weights are learned with ranking scores jointly and automatically, by alternately minimizing an objective function in an iterative algorithm. Experimental results on a subset of the ASTRAL SCOP protein domain database demonstrate that MultiG-Rank achieves a better ranking performance than single graph regularized ranking methods and pairwise similarity based ranking methods.Conclusion: The problem of graph model and parameter selection in graph regularized protein domain ranking can be solved effectively by combining multiple graphs. This aspect of generalization introduces a new frontier in applying multiple graphs to solving protein domain ranking applications. 2012 Wang et al; licensee BioMed Central Ltd.

Comparative analysis of gradient-field-based orientation estimation methods and regularized singular-value decomposition for fringe pattern processing.

Science.gov (United States)

Sun, Qi; Fu, Shujun

2017-09-20

Fringe orientation is an important feature of fringe patterns and has a wide range of applications such as guiding fringe pattern filtering, phase unwrapping, and abstraction. Estimating fringe orientation is a basic task for subsequent processing of fringe patterns. However, various noise, singular and obscure points, and orientation data degeneration lead to inaccurate calculations of fringe orientation. Thus, to deepen the understanding of orientation estimation and to better guide orientation estimation in fringe pattern processing, some advanced gradient-field-based orientation estimation methods are compared and analyzed. At the same time, following the ideas of smoothing regularization and computing of bigger gradient fields, a regularized singular-value decomposition (RSVD) technique is proposed for fringe orientation estimation. To compare the performance of these gradient-field-based methods, quantitative results and visual effect maps of orientation estimation are given on simulated and real fringe patterns that demonstrate that the RSVD produces the best estimation results at a cost of relatively less time.

Manifold regularized multitask feature learning for multimodality disease classification.

Science.gov (United States)

Jie, Biao; Zhang, Daoqiang; Cheng, Bo; Shen, Dinggang

2015-02-01

Multimodality based methods have shown great advantages in classification of Alzheimer's disease (AD) and its prodromal stage, that is, mild cognitive impairment (MCI). Recently, multitask feature selection methods are typically used for joint selection of common features across multiple modalities. However, one disadvantage of existing multimodality based methods is that they ignore the useful data distribution information in each modality, which is essential for subsequent classification. Accordingly, in this paper we propose a manifold regularized multitask feature learning method to preserve both the intrinsic relatedness among multiple modalities of data and the data distribution information in each modality. Specifically, we denote the feature learning on each modality as a single task, and use group-sparsity regularizer to capture the intrinsic relatedness among multiple tasks (i.e., modalities) and jointly select the common features from multiple tasks. Furthermore, we introduce a new manifold-based Laplacian regularizer to preserve the data distribution information from each task. Finally, we use the multikernel support vector machine method to fuse multimodality data for eventual classification. Conversely, we also extend our method to the semisupervised setting, where only partial data are labeled. We evaluate our method using the baseline magnetic resonance imaging (MRI), fluorodeoxyglucose positron emission tomography (FDG-PET), and cerebrospinal fluid (CSF) data of subjects from AD neuroimaging initiative database. The experimental results demonstrate that our proposed method can not only achieve improved classification performance, but also help to discover the disease-related brain regions useful for disease diagnosis. © 2014 Wiley Periodicals, Inc.

Regularized Regression and Density Estimation based on Optimal Transport

KAUST Repository

Burger, M.

2012-03-11

The aim of this paper is to investigate a novel nonparametric approach for estimating and smoothing density functions as well as probability densities from discrete samples based on a variational regularization method with the Wasserstein metric as a data fidelity. The approach allows a unified treatment of discrete and continuous probability measures and is hence attractive for various tasks. In particular, the variational model for special regularization functionals yields a natural method for estimating densities and for preserving edges in the case of total variation regularization. In order to compute solutions of the variational problems, a regularized optimal transport problem needs to be solved, for which we discuss several formulations and provide a detailed analysis. Moreover, we compute special self-similar solutions for standard regularization functionals and we discuss several computational approaches and results. © 2012 The Author(s).

Generalization Performance of Regularized Ranking With Multiscale Kernels.

Science.gov (United States)

Zhou, Yicong; Chen, Hong; Lan, Rushi; Pan, Zhibin

2016-05-01

The regularized kernel method for the ranking problem has attracted increasing attentions in machine learning. The previous regularized ranking algorithms are usually based on reproducing kernel Hilbert spaces with a single kernel. In this paper, we go beyond this framework by investigating the generalization performance of the regularized ranking with multiscale kernels. A novel ranking algorithm with multiscale kernels is proposed and its representer theorem is proved. We establish the upper bound of the generalization error in terms of the complexity of hypothesis spaces. It shows that the multiscale ranking algorithm can achieve satisfactory learning rates under mild conditions. Experiments demonstrate the effectiveness of the proposed method for drug discovery and recommendation tasks.

Abstract Word Definition in Patients with Amnestic Mild Cognitive Impairment

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Kim, Soo Ryon; Baek, Min Jae; Kim, HyangHee

2015-01-01

The aims of this study were to investigate concrete and abstract word definition ability (1) between patients with amnestic mild cognitive impairment (aMCI) and normal adults and (2) between the aMCI subtypes (i.e., amnestic single-domain MCI and amnestic multidomain MCI; asMCI and amMCI) and normal controls. The 68 patients with aMCI (29 asMCI and 39 amMCI) and 93 age- and education-matched normal adults performed word definition tasks composed of five concrete (e.g., train) and five abstract nouns (e.g., jealousy). Task performances were analyzed on total score, number of core meanings, and number of supplementary meanings. The results were as follows. First, the aMCI patients scored significantly poorer than the normal controls in only abstract word definition. Second, both subtypes of aMCI performed worse than the controls in only abstract word definition. In conclusion, a definition task of abstract rather than concrete concepts may provide richer information to show semantic impairment of aMCI. PMID:26347214

Abstract Word Definition in Patients with Amnestic Mild Cognitive Impairment

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Soo Ryon Kim

2015-01-01

Full Text Available The aims of this study were to investigate concrete and abstract word definition ability (1 between patients with amnestic mild cognitive impairment (aMCI and normal adults and (2 between the aMCI subtypes (i.e., amnestic single-domain MCI and amnestic multidomain MCI; asMCI and amMCI and normal controls. The 68 patients with aMCI (29 asMCI and 39 amMCI and 93 age- and education-matched normal adults performed word definition tasks composed of five concrete (e.g., train and five abstract nouns (e.g., jealousy. Task performances were analyzed on total score, number of core meanings, and number of supplementary meanings. The results were as follows. First, the aMCI patients scored significantly poorer than the normal controls in only abstract word definition. Second, both subtypes of aMCI performed worse than the controls in only abstract word definition. In conclusion, a definition task of abstract rather than concrete concepts may provide richer information to show semantic impairment of aMCI.

Knowledge acquisition for temporal abstraction.

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Stein, A; Musen, M A; Shahar, Y

1996-01-01

Temporal abstraction is the task of detecting relevant patterns in data over time. The knowledge-based temporal-abstraction method uses knowledge about a clinical domain's contexts, external events, and parameters to create meaningful interval-based abstractions from raw time-stamped clinical data. In this paper, we describe the acquisition and maintenance of domain-specific temporal-abstraction knowledge. Using the PROTEGE-II framework, we have designed a graphical tool for acquiring temporal knowledge directly from expert physicians, maintaining the knowledge in a sharable form, and converting the knowledge into a suitable format for use by an appropriate problem-solving method. In initial tests, the tool offered significant gains in our ability to rapidly acquire temporal knowledge and to use that knowledge to perform automated temporal reasoning.

Higher order total variation regularization for EIT reconstruction.

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Gong, Bo; Schullcke, Benjamin; Krueger-Ziolek, Sabine; Zhang, Fan; Mueller-Lisse, Ullrich; Moeller, Knut

2018-01-08

Electrical impedance tomography (EIT) attempts to reveal the conductivity distribution of a domain based on the electrical boundary condition. This is an ill-posed inverse problem; its solution is very unstable. Total variation (TV) regularization is one of the techniques commonly employed to stabilize reconstructions. However, it is well known that TV regularization induces staircase effects, which are not realistic in clinical applications. To reduce such artifacts, modified TV regularization terms considering a higher order differential operator were developed in several previous studies. One of them is called total generalized variation (TGV) regularization. TGV regularization has been successively applied in image processing in a regular grid context. In this study, we adapted TGV regularization to the finite element model (FEM) framework for EIT reconstruction. Reconstructions using simulation and clinical data were performed. First results indicate that, in comparison to TV regularization, TGV regularization promotes more realistic images. Graphical abstract Reconstructed conductivity changes located on selected vertical lines. For each of the reconstructed images as well as the ground truth image, conductivity changes located along the selected left and right vertical lines are plotted. In these plots, the notation GT in the legend stands for ground truth, TV stands for total variation method, and TGV stands for total generalized variation method. Reconstructed conductivity distributions from the GREIT algorithm are also demonstrated.

The Role of Representations in Executive Function: Investigating a Developmental Link Between Flexibility and Abstraction

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Maria eKharitonova

2011-11-01

Full Text Available Young children often perseverate, engaging in previously correct, but no longer appropriate behaviors. One account posits that such perseveration results from the use of stimulus-specific representations of a situation, which are distinct from abstract, generalizable representations that support flexible behavior. Previous findings supported this account, demonstrating that only children who flexibly switch between rules could generalize their behavior to novel stimuli. However, this link between flexibility and generalization might reflect general cognitive abilities, or depend upon similarities across the measures or their temporal order. The current work examined these issues by testing the specificity and generality of this link. In two experiments with three-year-old children, flexibility was measured in terms of switching between rules in a card-sorting task, while abstraction was measured in terms of selecting which stimulus did not belong in an odd-one-out task. The link between flexibility and abstraction was general across (1 abstraction dimensions similar to or different from those in the card-sorting task and (2 abstraction tasks that preceded or followed the switching task. Good performance on abstraction and flexibility measures did not extend to all cognitive tasks, including an IQ measure, and dissociated from children’s ability to gaze at the correct stimulus in the odd-one-out task, suggesting that the link between flexibility and abstraction is specific to such measures, rather than reflecting general abilities that affect all tasks. We interpret these results in terms of the role that developing prefrontal cortical regions play in processes such as working memory, which can support both flexibility and abstraction.

Argument structure and the representation of abstract semantics.

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Javier Rodríguez-Ferreiro

Full Text Available According to the dual coding theory, differences in the ease of retrieval between concrete and abstract words are related to the exclusive dependence of abstract semantics on linguistic information. Argument structure can be considered a measure of the complexity of the linguistic contexts that accompany a verb. If the retrieval of abstract verbs relies more on the linguistic codes they are associated to, we could expect a larger effect of argument structure for the processing of abstract verbs. In this study, sets of length- and frequency-matched verbs including 40 intransitive verbs, 40 transitive verbs taking simple complements, and 40 transitive verbs taking sentential complements were presented in separate lexical and grammatical decision tasks. Half of the verbs were concrete and half were abstract. Similar results were obtained in the two tasks, with significant effects of imageability and transitivity. However, the interaction between these two variables was not significant. These results conflict with hypotheses assuming a stronger reliance of abstract semantics on linguistic codes. In contrast, our data are in line with theories that link the ease of retrieval with availability and robustness of semantic information.

Argument structure and the representation of abstract semantics.

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Rodríguez-Ferreiro, Javier; Andreu, Llorenç; Sanz-Torrent, Mònica

2014-01-01

According to the dual coding theory, differences in the ease of retrieval between concrete and abstract words are related to the exclusive dependence of abstract semantics on linguistic information. Argument structure can be considered a measure of the complexity of the linguistic contexts that accompany a verb. If the retrieval of abstract verbs relies more on the linguistic codes they are associated to, we could expect a larger effect of argument structure for the processing of abstract verbs. In this study, sets of length- and frequency-matched verbs including 40 intransitive verbs, 40 transitive verbs taking simple complements, and 40 transitive verbs taking sentential complements were presented in separate lexical and grammatical decision tasks. Half of the verbs were concrete and half were abstract. Similar results were obtained in the two tasks, with significant effects of imageability and transitivity. However, the interaction between these two variables was not significant. These results conflict with hypotheses assuming a stronger reliance of abstract semantics on linguistic codes. In contrast, our data are in line with theories that link the ease of retrieval with availability and robustness of semantic information.

UNFOLDED REGULAR AND SEMI-REGULAR POLYHEDRA

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IONIŢĂ Elena

2015-06-01

Full Text Available This paper proposes a presentation unfolding regular and semi-regular polyhedra. Regular polyhedra are convex polyhedra whose faces are regular and equal polygons, with the same number of sides, and whose polyhedral angles are also regular and equal. Semi-regular polyhedra are convex polyhedra with regular polygon faces, several types and equal solid angles of the same type. A net of a polyhedron is a collection of edges in the plane which are the unfolded edges of the solid. Modeling and unfolding Platonic and Arhimediene polyhedra will be using 3dsMAX program. This paper is intended as an example of descriptive geometry applications.

Fractional Regularization Term for Variational Image Registration

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Rafael Verdú-Monedero

2009-01-01

Full Text Available Image registration is a widely used task of image analysis with applications in many fields. Its classical formulation and current improvements are given in the spatial domain. In this paper a regularization term based on fractional order derivatives is formulated. This term is defined and implemented in the frequency domain by translating the energy functional into the frequency domain and obtaining the Euler-Lagrange equations which minimize it. The new regularization term leads to a simple formulation and design, being applicable to higher dimensions by using the corresponding multidimensional Fourier transform. The proposed regularization term allows for a real gradual transition from a diffusion registration to a curvature registration which is best suited to some applications and it is not possible in the spatial domain. Results with 3D actual images show the validity of this approach.

Multiple graph regularized nonnegative matrix factorization

KAUST Repository

Wang, Jim Jing-Yan

2013-10-01

Non-negative matrix factorization (NMF) has been widely used as a data representation method based on components. To overcome the disadvantage of NMF in failing to consider the manifold structure of a data set, graph regularized NMF (GrNMF) has been proposed by Cai et al. by constructing an affinity graph and searching for a matrix factorization that respects graph structure. Selecting a graph model and its corresponding parameters is critical for this strategy. This process is usually carried out by cross-validation or discrete grid search, which are time consuming and prone to overfitting. In this paper, we propose a GrNMF, called MultiGrNMF, in which the intrinsic manifold is approximated by a linear combination of several graphs with different models and parameters inspired by ensemble manifold regularization. Factorization metrics and linear combination coefficients of graphs are determined simultaneously within a unified object function. They are alternately optimized in an iterative algorithm, thus resulting in a novel data representation algorithm. Extensive experiments on a protein subcellular localization task and an Alzheimer\\'s disease diagnosis task demonstrate the effectiveness of the proposed algorithm. © 2013 Elsevier Ltd. All rights reserved.

Human visual system automatically represents large-scale sequential regularities.

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Kimura, Motohiro; Widmann, Andreas; Schröger, Erich

2010-03-04

Our brain recordings reveal that large-scale sequential regularities defined across non-adjacent stimuli can be automatically represented in visual sensory memory. To show that, we adopted an auditory paradigm developed by Sussman, E., Ritter, W., and Vaughan, H. G. Jr. (1998). Predictability of stimulus deviance and the mismatch negativity. NeuroReport, 9, 4167-4170, Sussman, E., and Gumenyuk, V. (2005). Organization of sequential sounds in auditory memory. NeuroReport, 16, 1519-1523 to the visual domain by presenting task-irrelevant infrequent luminance-deviant stimuli (D, 20%) inserted among task-irrelevant frequent stimuli being of standard luminance (S, 80%) in randomized (randomized condition, SSSDSSSSSDSSSSD...) and fixed manners (fixed condition, SSSSDSSSSDSSSSD...). Comparing the visual mismatch negativity (visual MMN), an event-related brain potential (ERP) index of memory-mismatch processes in human visual sensory system, revealed that visual MMN elicited by deviant stimuli was reduced in the fixed compared to the randomized condition. Thus, the large-scale sequential regularity being present in the fixed condition (SSSSD) must have been represented in visual sensory memory. Interestingly, this effect did not occur in conditions with stimulus-onset asynchronies (SOAs) of 480 and 800 ms but was confined to the 160-ms SOA condition supporting the hypothesis that large-scale regularity extraction was based on perceptual grouping of the five successive stimuli defining the regularity. 2010 Elsevier B.V. All rights reserved.

Regular exercise is associated with emotional resilience to acute stress in healthy adults

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Emma eChilds

2014-05-01

Full Text Available Physical activity has long been considered beneficial to health and regular exercise is purported to relieve stress. However empirical evidence demonstrating these effects is limited. In this study, we compared psychophysiological responses to an acute psychosocial stressor between individuals who did, or did not, report regular physical exercise. Healthy men and women (N=111 participated in two experimental sessions, one with the Trier Social Stress Test (TSST and one with a non-stressful control task. We measured heart rate, blood pressure, cortisol and self-reported mood before and at repeated times after the tasks.Individuals who reported physical exercise at least once per week exhibited lower heart rate at rest than non-exercisers, but the groups did not differ in their cardiovascular responses to the TSST. Level of habitual exercise did not influence self-reported mood before the tasks, but non-exercisers reported a greater decline in positive affect after the TSST in comparison to exercisers. These findings provide modest support for claims that regular exercise protects against the negative emotional consequences of stress, and suggest that exercise has beneficial effects in healthy individuals. These findings are limited by their correlational nature, and future prospective controlled studies on the effects of regular exercise on response to acute stress are needed.

Analytic semigroups and optimal regularity in parabolic problems

CERN Document Server

Lunardi, Alessandra

2012-01-01

The book shows how the abstract methods of analytic semigroups and evolution equations in Banach spaces can be fruitfully applied to the study of parabolic problems. Particular attention is paid to optimal regularity results in linear equations. Furthermore, these results are used to study several other problems, especially fully nonlinear ones. Owing to the new unified approach chosen, known theorems are presented from a novel perspective and new results are derived. The book is self-contained. It is addressed to PhD students and researchers interested in abstract evolution equations and in p

The Evolution of Frequency Distributions: Relating Regularization to Inductive Biases through Iterated Learning

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Reali, Florencia; Griffiths, Thomas L.

2009-01-01

The regularization of linguistic structures by learners has played a key role in arguments for strong innate constraints on language acquisition, and has important implications for language evolution. However, relating the inductive biases of learners to regularization behavior in laboratory tasks can be challenging without a formal model. In this…

Changes in prefrontal neuronal activity after learning to perform a spatial working memory task.

Science.gov (United States)

Qi, Xue-Lian; Meyer, Travis; Stanford, Terrence R; Constantinidis, Christos

2011-12-01

The prefrontal cortex is considered essential for learning to perform cognitive tasks though little is known about how the representation of stimulus properties is altered by learning. To address this issue, we recorded neuronal activity in monkeys before and after training on a task that required visual working memory. After the subjects learned to perform the task, we observed activation of more prefrontal neurons and increased activity during working memory maintenance. The working memory-related increase in firing rate was due mostly to regular-spiking putative pyramidal neurons. Unexpectedly, the selectivity of neurons for stimulus properties and the ability of neurons to discriminate between stimuli decreased as the information about stimulus properties was apparently present in neural firing prior to training and neuronal selectivity degraded after training in the task. The effect was robust and could not be accounted for by differences in sampling sites, selection of neurons, level of performance, or merely the elapse of time. The results indicate that, in contrast to the effects of perceptual learning, mastery of a cognitive task degrades the apparent stimulus selectivity as neurons represent more abstract information related to the task. This effect is countered by the recruitment of more neurons after training.

Cued Memory Reactivation During SWS Abolishes the Beneficial Effect of Sleep on Abstraction.

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Hennies, Nora; Lambon Ralph, Matthew A; Durrant, Simon J; Cousins, James N; Lewis, Penelope A

2017-08-01

Extracting regularities from stimuli in our environment and generalizing these to new situations are fundamental processes in human cognition. Sleep has been shown to enhance these processes, possibly by facilitating reactivation-triggered memory reorganization. Here, we assessed whether cued reactivation during slow wave sleep (SWS) promotes the beneficial effect of sleep on abstraction of statistical regularities. We used an auditory statistical learning task, in which the benefit of sleep has been firmly established. Participants were exposed to a probabilistically determined sequence of tones and subsequently tested for recognition of novel short sequences adhering to this same statistical pattern in both immediate and delayed recall sessions. In different groups, the exposure stream was replayed during SWS in the night between the recall sessions (SWS-replay group), in wake just before sleep (presleep replay group), or not at all (control group). Surprisingly, participants who received replay in sleep performed worse in the delayed recall session than the control and the presleep replay group. They also failed to show the association between SWS and task performance that has been observed in previous studies and was present in the controls. Importantly, sleep structure and sleep quality did not differ between groups, suggesting that replay during SWS did not impair sleep but rather disrupted or interfered with sleep-dependent mechanisms that underlie the extraction of the statistical pattern. These findings raise important questions about the scope of cued memory reactivation and the mechanisms that underlie sleep-related generalization. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Graph Regularized Auto-Encoders for Image Representation.

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Yiyi Liao; Yue Wang; Yong Liu

2017-06-01

Image representation has been intensively explored in the domain of computer vision for its significant influence on the relative tasks such as image clustering and classification. It is valuable to learn a low-dimensional representation of an image which preserves its inherent information from the original image space. At the perspective of manifold learning, this is implemented with the local invariant idea to capture the intrinsic low-dimensional manifold embedded in the high-dimensional input space. Inspired by the recent successes of deep architectures, we propose a local invariant deep nonlinear mapping algorithm, called graph regularized auto-encoder (GAE). With the graph regularization, the proposed method preserves the local connectivity from the original image space to the representation space, while the stacked auto-encoders provide explicit encoding model for fast inference and powerful expressive capacity for complex modeling. Theoretical analysis shows that the graph regularizer penalizes the weighted Frobenius norm of the Jacobian matrix of the encoder mapping, where the weight matrix captures the local property in the input space. Furthermore, the underlying effects on the hidden representation space are revealed, providing insightful explanation to the advantage of the proposed method. Finally, the experimental results on both clustering and classification tasks demonstrate the effectiveness of our GAE as well as the correctness of the proposed theoretical analysis, and it also suggests that GAE is a superior solution to the current deep representation learning techniques comparing with variant auto-encoders and existing local invariant methods.

Auditory temporal preparation induced by rhythmic cues during concurrent auditory working memory tasks.

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Cutanda, Diana; Correa, Ángel; Sanabria, Daniel

2015-06-01

The present study investigated whether participants can develop temporal preparation driven by auditory isochronous rhythms when concurrently performing an auditory working memory (WM) task. In Experiment 1, participants had to respond to an auditory target presented after a regular or an irregular sequence of auditory stimuli while concurrently performing a Sternberg-type WM task. Results showed that participants responded faster after regular compared with irregular rhythms and that this effect was not affected by WM load; however, the lack of a significant main effect of WM load made it difficult to draw any conclusion regarding the influence of the dual-task manipulation in Experiment 1. In order to enhance dual-task interference, Experiment 2 combined the auditory rhythm procedure with an auditory N-Back task, which required WM updating (monitoring and coding of the information) and was presumably more demanding than the mere rehearsal of the WM task used in Experiment 1. Results now clearly showed dual-task interference effects (slower reaction times [RTs] in the high- vs. the low-load condition). However, such interference did not affect temporal preparation induced by rhythms, with faster RTs after regular than after irregular sequences in the high-load and low-load conditions. These results revealed that secondary tasks demanding memory updating, relative to tasks just demanding rehearsal, produced larger interference effects on overall RTs in the auditory rhythm task. Nevertheless, rhythm regularity exerted a strong temporal preparation effect that survived the interference of the WM task even when both tasks competed for processing resources within the auditory modality. (c) 2015 APA, all rights reserved).

Does semantic impairment explain surface dyslexia? VLSM evidence for a double dissociation between regularization errors in reading and semantic errors in picture naming

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Sara Pillay

2014-04-01

adjacent posterior inferior temporal gyrus (blue in figure 1. In contrast, semantic errors during picture naming (red and pink in figure 1 and impaired performance on the semantic matching task (yellow and pink in figure 1 were correlated with more anterior temporal lobe damage and with inferior frontal gyrus involvement. There was substantial overlap between lesion correlates for the two explicit semantic tasks (pink in figure 1, but none between these areas and those correlated with regularization errors. This double dissociation is difficult to accommodate in terms of a common impairment underlying semantic deficits and regularization errors. Lesions in relatively anterior temporal regions appear to produce semantic deficits but not regularization errors, whereas more posterior temporal lesions produce regularization errors but not explicit semantic errors. One possibility is that this posterior temporal region stores whole word representations that do not include semantic information. Alternatively, these representations may include highly abstract and word-specific semantic information useful for computing phonology but not for more complex semantic tasks.

Task-based statistical image reconstruction for high-quality cone-beam CT

Science.gov (United States)

Dang, Hao; Webster Stayman, J.; Xu, Jennifer; Zbijewski, Wojciech; Sisniega, Alejandro; Mow, Michael; Wang, Xiaohui; Foos, David H.; Aygun, Nafi; Koliatsos, Vassilis E.; Siewerdsen, Jeffrey H.

2017-11-01

Task-based analysis of medical imaging performance underlies many ongoing efforts in the development of new imaging systems. In statistical image reconstruction, regularization is often formulated in terms to encourage smoothness and/or sharpness (e.g. a linear, quadratic, or Huber penalty) but without explicit formulation of the task. We propose an alternative regularization approach in which a spatially varying penalty is determined that maximizes task-based imaging performance at every location in a 3D image. We apply the method to model-based image reconstruction (MBIR—viz., penalized weighted least-squares, PWLS) in cone-beam CT (CBCT) of the head, focusing on the task of detecting a small, low-contrast intracranial hemorrhage (ICH), and we test the performance of the algorithm in the context of a recently developed CBCT prototype for point-of-care imaging of brain injury. Theoretical predictions of local spatial resolution and noise are computed via an optimization by which regularization (specifically, the quadratic penalty strength) is allowed to vary throughout the image to maximize local task-based detectability index ({{d}\\prime} ). Simulation studies and test-bench experiments were performed using an anthropomorphic head phantom. Three PWLS implementations were tested: conventional (constant) penalty; a certainty-based penalty derived to enforce constant point-spread function, PSF; and the task-based penalty derived to maximize local detectability at each location. Conventional (constant) regularization exhibited a fairly strong degree of spatial variation in {{d}\\prime} , and the certainty-based method achieved uniform PSF, but each exhibited a reduction in detectability compared to the task-based method, which improved detectability up to ~15%. The improvement was strongest in areas of high attenuation (skull base), where the conventional and certainty-based methods tended to over-smooth the data. The task-driven reconstruction method presents a

Perceptual, semantic and affective dimensions of experience of abstract and representational paintings

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Marković Slobodan

2011-01-01

Full Text Available In this study the difference between representational and abstract paintings in judgments on perceptual, semantic and affective dimensions was investigated. Two groups of participants judged the sets of representational and abstract paintings on three groups of dimensions: perceptual (Form, Color, Space and Complexity, semantic (Illusion-Construction of Reality, Expression, Ideology and Decoration, and affective (Hedonic Tone, Arousal, Relaxation and Regularity. The results have shown that representational paintings have higher judgments on the perceptual dimensions of Form and Complexity, the semantic dimension of the Illusion of Reality (the opposite pole of the Construction of Reality, and the affective dimension of Regularity. On the other hand, abstract paintings have higher judgments on the perceptual dimension of Color, the semantic dimensions of Construction of Reality (the opposite pole of the Illusion of Reality and Expression, and the affective dimension Arousal. A discriminant analysis indicated that all three sets of dimensions are relatively good predictors of the classification of representational and abstract paintings (61-100%. The results suggest that the subjective categorization of paintings is generally based on the recognizability of pictorial content (representational vs. abstract, but some formal or stylistic properties play a role in the categorization, as well: some expressionistic representational paintings were classified in an abstract category, and some geometrically abstract paintings were classified as representational.

Imaginal, semantic, and surface-level processing of concrete and abstract words: an electrophysiological investigation.

Science.gov (United States)

West, W C; Holcomb, P J

2000-11-01

Words representing concrete concepts are processed more quickly and efficiently than words representing abstract concepts. Concreteness effects have also been observed in studies using event-related brain potentials (ERPs). The aim of this study was to examine concrete and abstract words using both reaction time (RT) and ERP measurements to determine (1) at what point in the stream of cognitive processing concreteness effects emerge and (2) how different types of cognitive operations influence these concreteness effects. Three groups of subjects performed a sentence verification task in which the final word of each sentence was concrete or abstract. For each group the truthfulness judgment required either (1) image generation, (2) semantic decision, or (3) evaluation of surface characteristics. Concrete and abstract words produced similar RTs and ERPs in the surface task, suggesting that postlexical semantic processing is necessary to elicit concreteness effects. In both the semantic and imagery tasks, RTs were shorter for concrete than for abstract words. This difference was greatest in the imagery task. Also, in both of these tasks concrete words elicited more negative ERPs than abstract words between 300 and 550 msec (N400). This effect was widespread across the scalp and may reflect activation in a linguistic semantic system common to both concrete and abstract words. ERPs were also more negative for concrete than abstract words between 550 and 800 msec. This effect was more frontally distributed and was most evident in the imagery task. We propose that this later anterior effect represents a distinct ERP component (N700) that is sensitive to the use of mental imagery. The N700 may reflect the a access of specific characteristics of the imaged item or activation in a working memory system specific to mental imagery. These results also support the extended dual-coding hypothesis that superior associative connections and the use of mental imagery both contribute

A test of the symbol interdependency hypothesis with both concrete and abstract stimuli.

Science.gov (United States)

Malhi, Simritpal Kaur; Buchanan, Lori

2018-01-01

In Experiment 1, the symbol interdependency hypothesis was tested with both concrete and abstract stimuli. Symbolic (i.e., semantic neighbourhood distance) and embodied (i.e., iconicity) factors were manipulated in two tasks-one that tapped symbolic relations (i.e., semantic relatedness judgment) and another that tapped embodied relations (i.e., iconicity judgment). Results supported the symbol interdependency hypothesis in that the symbolic factor was recruited for the semantic relatedness task and the embodied factor was recruited for the iconicity task. Across tasks, and especially in the iconicity task, abstract stimuli resulted in shorter RTs. This finding was in contrast to the concreteness effect where concrete words result in shorter RTs. Experiment 2 followed up on this finding by replicating the iconicity task from Experiment 1 in an ERP paradigm. Behavioural results continued to show a reverse concreteness effect with shorter RTs for abstract stimuli. However, ERP results paralleled the N400 and anterior N700 concreteness effects found in the literature, with more negative amplitudes for concrete stimuli.

Multi-level meta-workflows: new concept for regularly occurring tasks in quantum chemistry.

Science.gov (United States)

Arshad, Junaid; Hoffmann, Alexander; Gesing, Sandra; Grunzke, Richard; Krüger, Jens; Kiss, Tamas; Herres-Pawlis, Sonja; Terstyanszky, Gabor

2016-01-01

In Quantum Chemistry, many tasks are reoccurring frequently, e.g. geometry optimizations, benchmarking series etc. Here, workflows can help to reduce the time of manual job definition and output extraction. These workflows are executed on computing infrastructures and may require large computing and data resources. Scientific workflows hide these infrastructures and the resources needed to run them. It requires significant efforts and specific expertise to design, implement and test these workflows. Many of these workflows are complex and monolithic entities that can be used for particular scientific experiments. Hence, their modification is not straightforward and it makes almost impossible to share them. To address these issues we propose developing atomic workflows and embedding them in meta-workflows. Atomic workflows deliver a well-defined research domain specific function. Publishing workflows in repositories enables workflow sharing inside and/or among scientific communities. We formally specify atomic and meta-workflows in order to define data structures to be used in repositories for uploading and sharing them. Additionally, we present a formal description focused at orchestration of atomic workflows into meta-workflows. We investigated the operations that represent basic functionalities in Quantum Chemistry, developed the relevant atomic workflows and combined them into meta-workflows. Having these workflows we defined the structure of the Quantum Chemistry workflow library and uploaded these workflows in the SHIWA Workflow Repository.Graphical AbstractMeta-workflows and embedded workflows in the template representation.

SATURATED ZONE FLOW AND TRANSPORT MODEL ABSTRACTION

International Nuclear Information System (INIS)

B.W. ARNOLD

2004-01-01

The purpose of the saturated zone (SZ) flow and transport model abstraction task is to provide radionuclide-transport simulation results for use in the total system performance assessment (TSPA) for license application (LA) calculations. This task includes assessment of uncertainty in parameters that pertain to both groundwater flow and radionuclide transport in the models used for this purpose. This model report documents the following: (1) The SZ transport abstraction model, which consists of a set of radionuclide breakthrough curves at the accessible environment for use in the TSPA-LA simulations of radionuclide releases into the biosphere. These radionuclide breakthrough curves contain information on radionuclide-transport times through the SZ. (2) The SZ one-dimensional (I-D) transport model, which is incorporated in the TSPA-LA model to simulate the transport, decay, and ingrowth of radionuclide decay chains in the SZ. (3) The analysis of uncertainty in groundwater-flow and radionuclide-transport input parameters for the SZ transport abstraction model and the SZ 1-D transport model. (4) The analysis of the background concentration of alpha-emitting species in the groundwater of the SZ

Object-oriented programming with gradual abstraction

DEFF Research Database (Denmark)

Nørmark, Kurt; Thomsen, Lone Leth; Thomsen, Bent

2013-01-01

We describe an experimental object-oriented programming language, ASL2, that supports program development by means of a series of abstraction steps. The language allows immediate object construction, and it is possible to use the constructed objects for concrete problem solving tasks. Classes...... restrictive. As a central mechanism, weakly classified objects are allowed to borrow methods from each other. ASL2 supports class generalization, as a counterpart to class specialization and inheritance in mainstream object-oriented programming languages. The final abstraction step discussed in this paper...

Abstract spatial concept priming dynamically influences real-world actions

Directory of Open Access Journals (Sweden)

Sarah M Tower-Richardi

2012-09-01

Full Text Available Experienced regularities in our perceptions and actions play important roles in grounding abstract concepts such as social status, time, and emotion. Might we similarly ground abstract spatial concepts in more experienced-based domains? The present experiment explores this possibility by implicitly priming abstract spatial terms (north, south, east, west and then measuring participants’ hand movement trajectories while they respond to a body-referenced spatial target (up, down, left, right in a verbal (Exp. 1 or spatial (Exp. 2 format. Results from two experiments demonstrate temporally-dynamic and prime-biased movement trajectories when the primes are incongruent with the targets (e.g., north – left, west – up. That is, priming abstract coordinate directions influences subsequent actions in response to concrete target directions. These findings provide the first evidence that abstract concepts of world-centered coordinate axes are implicitly understood in the context of concrete body-referenced axes; critically, this abstract-concrete relationship manifests in motor movements, and may have implications for spatial memory organization.

"Plug-and-play" edge-preserving regularization

DEFF Research Database (Denmark)

Chen, Donghui; Kilmer, Misha E.; Hansen, Per Christian

2014-01-01

In many inverse problems it is essential to use regularization methods that preserve edges in the reconstructions, and many reconstruction models have been developed for this task, such as the Total Variation (TV) approach. The associated algorithms are complex and require a good knowledge of large...... cosine transform.hence the term "plug-and-play" . We do not attempt to improve on TV reconstructions, but rather provide an easy-to-use approach to computing reconstructions with similar properties....

Identifying beneficial task relations for multi-task learning in deep neural networks

DEFF Research Database (Denmark)

Bingel, Joachim; Søgaard, Anders

2017-01-01

Multi-task learning (MTL) in deep neural networks for NLP has recently received increasing interest due to some compelling benefits, including its potential to efficiently regularize models and to reduce the need for labeled data. While it has brought significant improvements in a number of NLP...

A test of the symbol interdependency hypothesis with both concrete and abstract stimuli

Science.gov (United States)

Buchanan, Lori

2018-01-01

In Experiment 1, the symbol interdependency hypothesis was tested with both concrete and abstract stimuli. Symbolic (i.e., semantic neighbourhood distance) and embodied (i.e., iconicity) factors were manipulated in two tasks—one that tapped symbolic relations (i.e., semantic relatedness judgment) and another that tapped embodied relations (i.e., iconicity judgment). Results supported the symbol interdependency hypothesis in that the symbolic factor was recruited for the semantic relatedness task and the embodied factor was recruited for the iconicity task. Across tasks, and especially in the iconicity task, abstract stimuli resulted in shorter RTs. This finding was in contrast to the concreteness effect where concrete words result in shorter RTs. Experiment 2 followed up on this finding by replicating the iconicity task from Experiment 1 in an ERP paradigm. Behavioural results continued to show a reverse concreteness effect with shorter RTs for abstract stimuli. However, ERP results paralleled the N400 and anterior N700 concreteness effects found in the literature, with more negative amplitudes for concrete stimuli. PMID:29590121

Regular Breakfast and Blood Lead Levels among Preschool Children

Directory of Open Access Journals (Sweden)

Needleman Herbert

2011-04-01

Full Text Available Abstract Background Previous studies have shown that fasting increases lead absorption in the gastrointestinal tract of adults. Regular meals/snacks are recommended as a nutritional intervention for lead poisoning in children, but epidemiological evidence of links between fasting and blood lead levels (B-Pb is rare. The purpose of this study was to examine the association between eating a regular breakfast and B-Pb among children using data from the China Jintan Child Cohort Study. Methods Parents completed a questionnaire regarding children's breakfast-eating habit (regular or not, demographics, and food frequency. Whole blood samples were collected from 1,344 children for the measurements of B-Pb and micronutrients (iron, copper, zinc, calcium, and magnesium. B-Pb and other measures were compared between children with and without regular breakfast. Linear regression modeling was used to evaluate the association between regular breakfast and log-transformed B-Pb. The association between regular breakfast and risk of lead poisoning (B-Pb≥10 μg/dL was examined using logistic regression modeling. Results Median B-Pb among children who ate breakfast regularly and those who did not eat breakfast regularly were 6.1 μg/dL and 7.2 μg/dL, respectively. Eating breakfast was also associated with greater zinc blood levels. Adjusting for other relevant factors, the linear regression model revealed that eating breakfast regularly was significantly associated with lower B-Pb (beta = -0.10 units of log-transformed B-Pb compared with children who did not eat breakfast regularly, p = 0.02. Conclusion The present study provides some initial human data supporting the notion that eating a regular breakfast might reduce B-Pb in young children. To our knowledge, this is the first human study exploring the association between breakfast frequency and B-Pb in young children.

Old Romanian pluralized mass and abstract nouns

Directory of Open Access Journals (Sweden)

Gabriela Pană Dindelegan

2017-09-01

Full Text Available The analysis of a rich old Romanian corpus shows that the ‘pluralization’ of mass and abstract nouns is extremely frequent in old Romanian. The semantic effects of pluralization are similar for mass and abstract nouns, consisting in the creation of denotative and/or connotative semantic variants. Of the plural endings, –uri is specialized for the pluralization of mass nouns in Daco-Romanian. The evolution of the ending –uri illustrates the specific process by which a grammatical (plural morpheme is converted into a lexical morpheme (the so-called ‘lexical plurals’. ‘Lexical plurals’ have isolated occurrences in other Romance languages, but they have not reached the spread and regularity they display in Romanian.

Relationship between abstract thinking and eye gaze pattern in patients with schizophrenia

Science.gov (United States)

2014-01-01

Background Effective integration of visual information is necessary to utilize abstract thinking, but patients with schizophrenia have slow eye movement and usually explore limited visual information. This study examines the relationship between abstract thinking ability and the pattern of eye gaze in patients with schizophrenia using a novel theme identification task. Methods Twenty patients with schizophrenia and 22 healthy controls completed the theme identification task, in which subjects selected which word, out of a set of provided words, best described the theme of a picture. Eye gaze while performing the task was recorded by the eye tracker. Results Patients exhibited a significantly lower correct rate for theme identification and lesser fixation and saccade counts than controls. The correct rate was significantly correlated with the fixation count in patients, but not in controls. Conclusions Patients with schizophrenia showed impaired abstract thinking and decreased quality of gaze, which were positively associated with each other. Theme identification and eye gaze appear to be useful as tools for the objective measurement of abstract thinking in patients with schizophrenia. PMID:24739356

ESPR 2015. Abstracts

International Nuclear Information System (INIS)

2015-01-01

The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.

ESPR 2015. Abstracts

Energy Technology Data Exchange (ETDEWEB)

NONE

2015-05-10

The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.

Regularity theorem for functions that are extremal to Paley inequality ...

African Journals Online (AJOL)

Regularity theorem for functions that are extremal to Paley inequality. Seid Mohammed. Abstract. In this paper we study the asymptotic behavior of functions that are extremal to the inequality introduced by Paley (1932) via a normal family of subharmonic functions. SINET: Ethiopian Journal of Science Volume 24, No.

Diverse Regular Employees and Non-regular Employment (Japanese)

OpenAIRE

MORISHIMA Motohiro

2011-01-01

Currently there are high expectations for the introduction of policies related to diverse regular employees. These policies are a response to the problem of disparities between regular and non-regular employees (part-time, temporary, contract and other non-regular employees) and will make it more likely that workers can balance work and their private lives while companies benefit from the advantages of regular employment. In this paper, I look at two issues that underlie this discussion. The ...

Abstract decomposition theorem and applications

CERN Document Server

Grossberg, R; Grossberg, Rami; Lessmann, Olivier

2005-01-01

Let K be an Abstract Elementary Class. Under the asusmptions that K has a nicely behaved forking-like notion, regular types and existence of some prime models we establish a decomposition theorem for such classes. The decomposition implies a main gap result for the class K. The setting is general enough to cover \\aleph_0-stable first-order theories (proved by Shelah in 1982), Excellent Classes of atomic models of a first order tehory (proved Grossberg and Hart 1987) and the class of submodels of a large sequentially homogenuus \\aleph_0-stable model (which is new).

Communication and Agreement Abstractions for Fault-Tolerant Asynchronous Distributed Systems

CERN Document Server

Raynal, Michel

2010-01-01

Understanding distributed computing is not an easy task. This is due to the many facets of uncertainty one has to cope with and master in order to produce correct distributed software. Considering the uncertainty created by asynchrony and process crash failures in the context of message-passing systems, the book focuses on the main abstractions that one has to understand and master in order to be able to produce software with guaranteed properties. These fundamental abstractions are communication abstractions that allow the processes to communicate consistently (namely the register abstraction

Algorithm-Dependent Generalization Bounds for Multi-Task Learning.

Science.gov (United States)

Liu, Tongliang; Tao, Dacheng; Song, Mingli; Maybank, Stephen J

2017-02-01

Often, tasks are collected for multi-task learning (MTL) because they share similar feature structures. Based on this observation, in this paper, we present novel algorithm-dependent generalization bounds for MTL by exploiting the notion of algorithmic stability. We focus on the performance of one particular task and the average performance over multiple tasks by analyzing the generalization ability of a common parameter that is shared in MTL. When focusing on one particular task, with the help of a mild assumption on the feature structures, we interpret the function of the other tasks as a regularizer that produces a specific inductive bias. The algorithm for learning the common parameter, as well as the predictor, is thereby uniformly stable with respect to the domain of the particular task and has a generalization bound with a fast convergence rate of order O(1/n), where n is the sample size of the particular task. When focusing on the average performance over multiple tasks, we prove that a similar inductive bias exists under certain conditions on the feature structures. Thus, the corresponding algorithm for learning the common parameter is also uniformly stable with respect to the domains of the multiple tasks, and its generalization bound is of the order O(1/T), where T is the number of tasks. These theoretical analyses naturally show that the similarity of feature structures in MTL will lead to specific regularizations for predicting, which enables the learning algorithms to generalize fast and correctly from a few examples.

Cospectral Graphs and Regular Orthogonal Matrices of Level 2

NARCIS (Netherlands)

Abiad Monge, A.; Haemers, W.H.

2012-01-01

Abstract: For a graph Γ with adjacency matrix A, we consider a switching operation that takes Γ into a graph Γ' with adjacency matrix A', defined by A' = QtAQ, where Q is a regular orthogonal matrix of level 2 (that is, QtQ = I, Q1 = 1, 2Q is integral, and Q is not a permutation matrix). If such an

Benefits of regular aerobic exercise for executive functioning in healthy populations.

Science.gov (United States)

Guiney, Hayley; Machado, Liana

2013-02-01

Research suggests that regular aerobic exercise has the potential to improve executive functioning, even in healthy populations. The purpose of this review is to elucidate which components of executive functioning benefit from such exercise in healthy populations. In light of the developmental time course of executive functions, we consider separately children, young adults, and older adults. Data to date from studies of aging provide strong evidence of exercise-linked benefits related to task switching, selective attention, inhibition of prepotent responses, and working memory capacity; furthermore, cross-sectional fitness data suggest that working memory updating could potentially benefit as well. In young adults, working memory updating is the main executive function shown to benefit from regular exercise, but cross-sectional data further suggest that task-switching and post error performance may also benefit. In children, working memory capacity has been shown to benefit, and cross-sectional data suggest potential benefits for selective attention and inhibitory control. Although more research investigating exercise-related benefits for specific components of executive functioning is clearly needed in young adults and children, when considered across the age groups, ample evidence indicates that regular engagement in aerobic exercise can provide a simple means for healthy people to optimize a range of executive functions.

Spectral Regularization Algorithms for Learning Large Incomplete Matrices.

Science.gov (United States)

Mazumder, Rahul; Hastie, Trevor; Tibshirani, Robert

2010-03-01

We use convex relaxation techniques to provide a sequence of regularized low-rank solutions for large-scale matrix completion problems. Using the nuclear norm as a regularizer, we provide a simple and very efficient convex algorithm for minimizing the reconstruction error subject to a bound on the nuclear norm. Our algorithm Soft-Impute iteratively replaces the missing elements with those obtained from a soft-thresholded SVD. With warm starts this allows us to efficiently compute an entire regularization path of solutions on a grid of values of the regularization parameter. The computationally intensive part of our algorithm is in computing a low-rank SVD of a dense matrix. Exploiting the problem structure, we show that the task can be performed with a complexity linear in the matrix dimensions. Our semidefinite-programming algorithm is readily scalable to large matrices: for example it can obtain a rank-80 approximation of a 10(6) × 10(6) incomplete matrix with 10(5) observed entries in 2.5 hours, and can fit a rank 40 approximation to the full Netflix training set in 6.6 hours. Our methods show very good performance both in training and test error when compared to other competitive state-of-the art techniques.

Poisson image reconstruction with Hessian Schatten-norm regularization.

Science.gov (United States)

Lefkimmiatis, Stamatios; Unser, Michael

2013-11-01

Poisson inverse problems arise in many modern imaging applications, including biomedical and astronomical ones. The main challenge is to obtain an estimate of the underlying image from a set of measurements degraded by a linear operator and further corrupted by Poisson noise. In this paper, we propose an efficient framework for Poisson image reconstruction, under a regularization approach, which depends on matrix-valued regularization operators. In particular, the employed regularizers involve the Hessian as the regularization operator and Schatten matrix norms as the potential functions. For the solution of the problem, we propose two optimization algorithms that are specifically tailored to the Poisson nature of the noise. These algorithms are based on an augmented-Lagrangian formulation of the problem and correspond to two variants of the alternating direction method of multipliers. Further, we derive a link that relates the proximal map of an l(p) norm with the proximal map of a Schatten matrix norm of order p. This link plays a key role in the development of one of the proposed algorithms. Finally, we provide experimental results on natural and biological images for the task of Poisson image deblurring and demonstrate the practical relevance and effectiveness of the proposed framework.

STRUCTURE OPTIMIZATION OF RESERVATION BY PRECISE QUADRATIC REGULARIZATION

Directory of Open Access Journals (Sweden)

KOSOLAP A. I.

2015-11-01

Full Text Available The problem of optimization of the structure of systems redundancy elements. Such problems arise in the design of complex systems. To improve the reliability of operation of such systems of its elements are duplicated. This increases system cost and improves its reliability. When optimizing these systems is maximized probability of failure of the entire system while limiting its cost or the cost is minimized for a given probability of failure-free operation. A mathematical model of the problem is a discrete backup multiextremal. To search for the global extremum of currently used methods of Lagrange multipliers, coordinate descent, dynamic programming, random search. These methods guarantee a just and local solutions are used in the backup tasks of small dimension. In the work for solving redundancy uses a new method for accurate quadratic regularization. This method allows you to convert the original discrete problem to the maximization of multi vector norm on a convex set. This means that the diversity of the tasks given to the problem of redundancy maximize vector norm on a convex set. To solve the problem, a reformed straightdual interior point methods. Currently, it is the best method for local optimization of nonlinear problems. Transformed the task includes a new auxiliary variable, which is determined by dichotomy. There have been numerous comparative numerical experiments in problems with the number of redundant subsystems to one hundred. These experiments confirm the effectiveness of the method of precise quadratic regularization for solving problems of redundancy.

Towards a guideline for selecting the appropriate abstraction level for building systems simulation

NARCIS (Netherlands)

Trcka, M.; Hensen, J.L.M.

2006-01-01

Each modeler meets a challenging task of abstracting the relevant physical behavior of the system to be modeled. What physical phenomena are important for the particular simulation task and what models to use are the questions that need to be answered every time when performing a simulation task.

Coordinate-invariant regularization

International Nuclear Information System (INIS)

Halpern, M.B.

1987-01-01

A general phase-space framework for coordinate-invariant regularization is given. The development is geometric, with all regularization contained in regularized DeWitt Superstructures on field deformations. Parallel development of invariant coordinate-space regularization is obtained by regularized functional integration of the momenta. As representative examples of the general formulation, the regularized general non-linear sigma model and regularized quantum gravity are discussed. copyright 1987 Academic Press, Inc

Statistical learning is constrained to less abstract patterns in complex sensory input (but not the least).

Science.gov (United States)

Emberson, Lauren L; Rubinstein, Dani Y

2016-08-01

The influence of statistical information on behavior (either through learning or adaptation) is quickly becoming foundational to many domains of cognitive psychology and cognitive neuroscience, from language comprehension to visual development. We investigate a central problem impacting these diverse fields: when encountering input with rich statistical information, are there any constraints on learning? This paper examines learning outcomes when adult learners are given statistical information across multiple levels of abstraction simultaneously: from abstract, semantic categories of everyday objects to individual viewpoints on these objects. After revealing statistical learning of abstract, semantic categories with scrambled individual exemplars (Exp. 1), participants viewed pictures where the categories as well as the individual objects predicted picture order (e.g., bird1-dog1, bird2-dog2). Our findings suggest that participants preferentially encode the relationships between the individual objects, even in the presence of statistical regularities linking semantic categories (Exps. 2 and 3). In a final experiment we investigate whether learners are biased towards learning object-level regularities or simply construct the most detailed model given the data (and therefore best able to predict the specifics of the upcoming stimulus) by investigating whether participants preferentially learn from the statistical regularities linking individual snapshots of objects or the relationship between the objects themselves (e.g., bird_picture1-dog_picture1, bird_picture2-dog_picture2). We find that participants fail to learn the relationships between individual snapshots, suggesting a bias towards object-level statistical regularities as opposed to merely constructing the most complete model of the input. This work moves beyond the previous existence proofs that statistical learning is possible at both very high and very low levels of abstraction (categories vs. individual

Assessment of abstract reasoning abilities in alcohol-dependent subjects: an fMRI study

International Nuclear Information System (INIS)

Bagga, Deepika; Singh, Namita; Singh, Sadhana; Modi, Shilpi; Kumar, Pawan; Bhattacharya, D.; Garg, Mohan L.; Khushu, Subash

2014-01-01

Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance. (orig.)

Assessment of abstract reasoning abilities in alcohol-dependent subjects: an fMRI study

Energy Technology Data Exchange (ETDEWEB)

Bagga, Deepika; Singh, Namita; Singh, Sadhana; Modi, Shilpi; Kumar, Pawan [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Centre, Delhi (India); Bhattacharya, D. [Base Hospital, Department of Psychiatry, Delhi Cantt (India); Garg, Mohan L. [Panjab University, Department of Biophysics, Chandigarh (India); Khushu, Subash [Institute of Nuclear Medicine and Allied Sciences (INMAS), NMR Research Centre, Delhi (India); INMAS, DRDO, NMR Research Centre, Delhi (India)

2014-01-15

Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance. (orig.)

Do fights prohibit helping? : the influence of task interdependence and conflict norms on helping behavior during task conflict

NARCIS (Netherlands)

Rispens, S.

2009-01-01

Abstract: Purpose – The purpose of this paper is to examine the effects of group conflict norms and task interdependence on individuals' willingness to help others under conditions of task conflict to better understand how group characteristics influence individual helping behavior.

Total variation regularization for fMRI-based prediction of behavior

Science.gov (United States)

Michel, Vincent; Gramfort, Alexandre; Varoquaux, Gaël; Eger, Evelyn; Thirion, Bertrand

2011-01-01

While medical imaging typically provides massive amounts of data, the extraction of relevant information for predictive diagnosis remains a difficult challenge. Functional MRI (fMRI) data, that provide an indirect measure of task-related or spontaneous neuronal activity, are classically analyzed in a mass-univariate procedure yielding statistical parametric maps. This analysis framework disregards some important principles of brain organization: population coding, distributed and overlapping representations. Multivariate pattern analysis, i.e., the prediction of behavioural variables from brain activation patterns better captures this structure. To cope with the high dimensionality of the data, the learning method has to be regularized. However, the spatial structure of the image is not taken into account in standard regularization methods, so that the extracted features are often hard to interpret. More informative and interpretable results can be obtained with the ℓ1 norm of the image gradient, a.k.a. its Total Variation (TV), as regularization. We apply for the first time this method to fMRI data, and show that TV regularization is well suited to the purpose of brain mapping while being a powerful tool for brain decoding. Moreover, this article presents the first use of TV regularization for classification. PMID:21317080

Rhetorical Variation across Research Article Abstracts in Environmental Science and Applied Linguistics

Science.gov (United States)

Saeeaw, Supachai; Tangkiengsirisin, Supong

2014-01-01

Abstract is of a pivotal genre in scientific communication, assisting not only highly selective readers with judgment of the pertinent articles but also researchers in disseminating new knowledge and intellectual discoveries. Difficult yet challenging, however, is the task of writing effective abstracts particularly among non-English speaking…

Selection of regularization parameter for l1-regularized damage detection

Science.gov (United States)

Hou, Rongrong; Xia, Yong; Bao, Yuequan; Zhou, Xiaoqing

2018-06-01

The l1 regularization technique has been developed for structural health monitoring and damage detection through employing the sparsity condition of structural damage. The regularization parameter, which controls the trade-off between data fidelity and solution size of the regularization problem, exerts a crucial effect on the solution. However, the l1 regularization problem has no closed-form solution, and the regularization parameter is usually selected by experience. This study proposes two strategies of selecting the regularization parameter for the l1-regularized damage detection problem. The first method utilizes the residual and solution norms of the optimization problem and ensures that they are both small. The other method is based on the discrepancy principle, which requires that the variance of the discrepancy between the calculated and measured responses is close to the variance of the measurement noise. The two methods are applied to a cantilever beam and a three-story frame. A range of the regularization parameter, rather than one single value, can be determined. When the regularization parameter in this range is selected, the damage can be accurately identified even for multiple damage scenarios. This range also indicates the sensitivity degree of the damage identification problem to the regularization parameter.

Universal Regularizers For Robust Sparse Coding and Modeling

OpenAIRE

Ramirez, Ignacio; Sapiro, Guillermo

2010-01-01

Sparse data models, where data is assumed to be well represented as a linear combination of a few elements from a dictionary, have gained considerable attention in recent years, and their use has led to state-of-the-art results in many signal and image processing tasks. It is now well understood that the choice of the sparsity regularization term is critical in the success of such models. Based on a codelength minimization interpretation of sparse coding, and using tools from universal coding...

The relationship between regular sports participation and vigilance in male and female adolescents.

Science.gov (United States)

Ballester, Rafael; Huertas, Florentino; Yuste, Francisco Javier; Llorens, Francesc; Sanabria, Daniel

2015-01-01

The present study investigated the relationship between regular sport participation (soccer) and vigilance performance. Two groups of male and female adolescents differentiated in terms of their sport participation (athletes, n = 39, and non-athletes, n = 36) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In the other session, participants completed the Psychomotor Vigilance Task (PVT) to evaluate their vigilance performance. Perceived arousal prior to the task and motivation toward the task were also measured in the PVT session. The results revealed that athletes had better cardiovascular fitness and showed better performance in the PVT. However, correlation analyses did not show any significant relationship between cardiovascular fitness and performance in the PVT. Athletes showed larger scores in motivation and perceived arousal measures with respect to non-athletes, although, once again, these variables were not correlated with PVT performance. Gender differences were observed only in the Leger test, with males showing greater fitness level than females. The major outcome of this research points to a positive relationship between regular sport participation and vigilance during adolescence. This relationship did not seem to be influenced by gender, perceived arousal, motivation toward the task or cardiovascular fitness. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between physical activity and cognitive functioning.

The Risky Path to a Followership Identity: From Abstract Concept to Situated Reality

DEFF Research Database (Denmark)

Larsson, Magnus; Nielsen, Mie Femø

2017-01-01

. The findings reveal the risks of misidentifying the task at hand, of being too authoritative, and of claiming too much knowledge. Also, our analyses highlight that leader and follower roles remain abstract in workplace interactions and, instead, people focus more on negotiated, task-oriented, practical...

Imbalance of positive and negative links induces regularity

International Nuclear Information System (INIS)

Kamal, Neeraj Kumar; Sinha, Sudeshna

2011-01-01

Research highlights: → We consider the behaviour of a random weighted network with chaotic neuronal dynamics at the nodes. → We investigate the effect of the balance of positive and negative links on dynamical regularity. → We find that when the connections are predominantly excitatory or inhibitory, one obtains a spatiotemporal fixed point. → However, when the links are balanced, the chaotic nature of the nodal dynamics of the uncoupled case is preserved. → Further we observe that larger network size leads to greater spatiotemporal regularity. - Abstract: We investigate the effect of the interplay of positive and negative links, on the dynamical regularity of a random weighted network, with neuronal dynamics at the nodes. We investigate how the mean J-bar and the variance of the weights of links, influence the spatiotemporal regularity of this dynamical network. We find that when the connections are predominantly positive (i.e. the links are mostly excitatory, with J-bar>0) the spatiotemporal fixed point is stable. A similar trend is observed when the connections are predominantly negative (i.e. the links are mostly inhibitory, with J-bar<0). However, when the positive and negative feedback is quite balanced (namely, when the mean of the connection weights is close to zero) one observes spatiotemporal chaos. That is, the balance of excitatory and inhibitory connections preserves the chaotic nature of the uncoupled case. To be brought to an inactive state one needs one type of connection (either excitatory or inhibitory) to dominate. Further we observe that larger network size leads to greater spatiotemporal regularity. We rationalize our observations through mean field analysis of the network dynamics.

Task conflict and proactive control: A computational theory of the Stroop task.

Science.gov (United States)

Kalanthroff, Eyal; Davelaar, Eddy J; Henik, Avishai; Goldfarb, Liat; Usher, Marius

2018-01-01

The Stroop task is a central experimental paradigm used to probe cognitive control by measuring the ability of participants to selectively attend to task-relevant information and inhibit automatic task-irrelevant responses. Research has revealed variability in both experimental manipulations and individual differences. Here, we focus on a particular source of Stroop variability, the reverse-facilitation (RF; faster responses to nonword neutral stimuli than to congruent stimuli), which has recently been suggested as a signature of task conflict. We first review the literature that shows RF variability in the Stroop task, both with regard to experimental manipulations and to individual differences. We suggest that task conflict variability can be understood as resulting from the degree of proactive control that subjects recruit in advance of the Stroop stimulus. When the proactive control is high, task conflict does not arise (or is resolved very quickly), resulting in regular Stroop facilitation. When proactive control is low, task conflict emerges, leading to a slow-down in congruent and incongruent (but not in neutral) trials and thus to Stroop RF. To support this suggestion, we present a computational model of the Stroop task, which includes the resolution of task conflict and its modulation by proactive control. Results show that our model (a) accounts for the variability in Stroop-RF reported in the experimental literature, and (b) solves a challenge to previous Stroop models-their ability to account for reaction time distributional properties. Finally, we discuss theoretical implications to Stroop measures and control deficits observed in some psychopathologies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Human visual system automatically encodes sequential regularities of discrete events.

Science.gov (United States)

Kimura, Motohiro; Schröger, Erich; Czigler, István; Ohira, Hideki

2010-06-01

For our adaptive behavior in a dynamically changing environment, an essential task of the brain is to automatically encode sequential regularities inherent in the environment into a memory representation. Recent studies in neuroscience have suggested that sequential regularities embedded in discrete sensory events are automatically encoded into a memory representation at the level of the sensory system. This notion is largely supported by evidence from investigations using auditory mismatch negativity (auditory MMN), an event-related brain potential (ERP) correlate of an automatic memory-mismatch process in the auditory sensory system. However, it is still largely unclear whether or not this notion can be generalized to other sensory modalities. The purpose of the present study was to investigate the contribution of the visual sensory system to the automatic encoding of sequential regularities using visual mismatch negativity (visual MMN), an ERP correlate of an automatic memory-mismatch process in the visual sensory system. To this end, we conducted a sequential analysis of visual MMN in an oddball sequence consisting of infrequent deviant and frequent standard stimuli, and tested whether the underlying memory representation of visual MMN generation contains only a sensory memory trace of standard stimuli (trace-mismatch hypothesis) or whether it also contains sequential regularities extracted from the repetitive standard sequence (regularity-violation hypothesis). The results showed that visual MMN was elicited by first deviant (deviant stimuli following at least one standard stimulus), second deviant (deviant stimuli immediately following first deviant), and first standard (standard stimuli immediately following first deviant), but not by second standard (standard stimuli immediately following first standard). These results are consistent with the regularity-violation hypothesis, suggesting that the visual sensory system automatically encodes sequential

Subcortical processing of speech regularities underlies reading and music aptitude in children

Science.gov (United States)

2011-01-01

Background Neural sensitivity to acoustic regularities supports fundamental human behaviors such as hearing in noise and reading. Although the failure to encode acoustic regularities in ongoing speech has been associated with language and literacy deficits, how auditory expertise, such as the expertise that is associated with musical skill, relates to the brainstem processing of speech regularities is unknown. An association between musical skill and neural sensitivity to acoustic regularities would not be surprising given the importance of repetition and regularity in music. Here, we aimed to define relationships between the subcortical processing of speech regularities, music aptitude, and reading abilities in children with and without reading impairment. We hypothesized that, in combination with auditory cognitive abilities, neural sensitivity to regularities in ongoing speech provides a common biological mechanism underlying the development of music and reading abilities. Methods We assessed auditory working memory and attention, music aptitude, reading ability, and neural sensitivity to acoustic regularities in 42 school-aged children with a wide range of reading ability. Neural sensitivity to acoustic regularities was assessed by recording brainstem responses to the same speech sound presented in predictable and variable speech streams. Results Through correlation analyses and structural equation modeling, we reveal that music aptitude and literacy both relate to the extent of subcortical adaptation to regularities in ongoing speech as well as with auditory working memory and attention. Relationships between music and speech processing are specifically driven by performance on a musical rhythm task, underscoring the importance of rhythmic regularity for both language and music. Conclusions These data indicate common brain mechanisms underlying reading and music abilities that relate to how the nervous system responds to regularities in auditory input

Subcortical processing of speech regularities underlies reading and music aptitude in children.

Science.gov (United States)

Strait, Dana L; Hornickel, Jane; Kraus, Nina

2011-10-17

Neural sensitivity to acoustic regularities supports fundamental human behaviors such as hearing in noise and reading. Although the failure to encode acoustic regularities in ongoing speech has been associated with language and literacy deficits, how auditory expertise, such as the expertise that is associated with musical skill, relates to the brainstem processing of speech regularities is unknown. An association between musical skill and neural sensitivity to acoustic regularities would not be surprising given the importance of repetition and regularity in music. Here, we aimed to define relationships between the subcortical processing of speech regularities, music aptitude, and reading abilities in children with and without reading impairment. We hypothesized that, in combination with auditory cognitive abilities, neural sensitivity to regularities in ongoing speech provides a common biological mechanism underlying the development of music and reading abilities. We assessed auditory working memory and attention, music aptitude, reading ability, and neural sensitivity to acoustic regularities in 42 school-aged children with a wide range of reading ability. Neural sensitivity to acoustic regularities was assessed by recording brainstem responses to the same speech sound presented in predictable and variable speech streams. Through correlation analyses and structural equation modeling, we reveal that music aptitude and literacy both relate to the extent of subcortical adaptation to regularities in ongoing speech as well as with auditory working memory and attention. Relationships between music and speech processing are specifically driven by performance on a musical rhythm task, underscoring the importance of rhythmic regularity for both language and music. These data indicate common brain mechanisms underlying reading and music abilities that relate to how the nervous system responds to regularities in auditory input. Definition of common biological underpinnings

Making Sense of Abstract Algebra: Exploring Secondary Teachers' Understandings of Inverse Functions in Relation to Its Group Structure

Science.gov (United States)

Wasserman, Nicholas H.

2017-01-01

This article draws on semi-structured, task-based interviews to explore secondary teachers' (N = 7) understandings of inverse functions in relation to abstract algebra. In particular, a concept map task is used to understand the degree to which participants, having recently taken an abstract algebra course, situated inverse functions within its…

Business process model abstraction : a definition, catalog, and survey

NARCIS (Netherlands)

Smirnov, S.; Reijers, H.A.; Weske, M.H.; Nugteren, T.

2012-01-01

The discipline of business process management aims at capturing, understanding, and improving work in organizations by using process models as central artifacts. Since business-oriented tasks require different information from such models to be highlighted, a range of abstraction techniques has been

Brain imaging study of the acute effects of Delta9-tetrahydrocannabinol (THC) on attention and motor coordination in regular users of marijuana.

Science.gov (United States)

Weinstein, Aviv; Brickner, Orit; Lerman, Hedva; Greemland, Mazal; Bloch, Miki; Lester, Hava; Chisin, Roland; Mechoulam, Raphael; Bar-Hamburger, Rachel; Freedman, Nanette; Even-Sapir, Einat

2008-01-01

Twelve regular users of marijuana underwent two positron emission tomography (PET) scans using [18F] Fluorodeoxyglucose (FDG), one while subject to the effects of 17 mg THC, the other without THC. In both sessions, a virtual reality maze task was performed during the FDG uptake period. When subject to the effects of 17 mg THC, regular marijuana smokers hit the walls more often on the virtual maze task than without THC. Compared to results without THC, 17 mg THC increased brain metabolism during task performance in areas that are associated with motor coordination and attention in the middle and medial frontal cortices and anterior cingulate, and reduced metabolism in areas that are related to visual integration of motion in the occipital lobes. These findings suggest that in regular marijuana users, the immediate effects of marijuana may impact on cognitive-motor skills and brain mechanisms that modulate coordinated movement and driving.

Design and Validation of HABTA: Human Attention-Based Task Allocator (Extended Abstract)

NARCIS (Netherlands)

Maanen, P.P. van; Koning, L. de; Dongen, C.J.G. van

2008-01-01

Several challenges can be identified for work on future naval platforms. Information volumes for navigation, system monitoring, and tactical tasks will increase as the complexity of the internal and external environment also increases. The trend of reduced manning is expected to continue as a result

Incorporating Language Structure in a Communicative Task: An Analysis of the Language Component of a Communicative Task in the LINC Home Study Program

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Lenchuk, Iryna

2014-01-01

The purpose of this article is to analyze a task included in the LINC Home Study (LHS) program. LHS is a federally funded distance education program offered to newcomers to Canada who are unable to attend regular LINC classes. A task, in which a language structure (a gerund) is chosen and analyzed, was selected from one instructional module of LHS…

Overview of the ID, EPI and REL tasks of BioNLP Shared Task 2011

Directory of Open Access Journals (Sweden)

Pyysalo Sampo

2012-06-01

Full Text Available Abstract We present the preparation, resources, results and analysis of three tasks of the BioNLP Shared Task 2011: the main tasks on Infectious Diseases (ID and Epigenetics and Post-translational Modifications (EPI, and the supporting task on Entity Relations (REL. The two main tasks represent extensions of the event extraction model introduced in the BioNLP Shared Task 2009 (ST'09 to two new areas of biomedical scientific literature, each motivated by the needs of specific biocuration tasks. The ID task concerns the molecular mechanisms of infection, virulence and resistance, focusing in particular on the functions of a class of signaling systems that are ubiquitous in bacteria. The EPI task is dedicated to the extraction of statements regarding chemical modifications of DNA and proteins, with particular emphasis on changes relating to the epigenetic control of gene expression. By contrast to these two application-oriented main tasks, the REL task seeks to support extraction in general by separating challenges relating to part-of relations into a subproblem that can be addressed by independent systems. Seven groups participated in each of the two main tasks and four groups in the supporting task. The participating systems indicated advances in the capability of event extraction methods and demonstrated generalization in many aspects: from abstracts to full texts, from previously considered subdomains to new ones, and from the ST'09 extraction targets to other entities and events. The highest performance achieved in the supporting task REL, 58% F-score, is broadly comparable with levels reported for other relation extraction tasks. For the ID task, the highest-performing system achieved 56% F-score, comparable to the state-of-the-art performance at the established ST'09 task. In the EPI task, the best result was 53% F-score for the full set of extraction targets and 69% F-score for a reduced set of core extraction targets, approaching a level

Processing SPARQL queries with regular expressions in RDF databases

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Cho Hune

2011-03-01

Full Text Available Abstract Background As the Resource Description Framework (RDF data model is widely used for modeling and sharing a lot of online bioinformatics resources such as Uniprot (dev.isb-sib.ch/projects/uniprot-rdf or Bio2RDF (bio2rdf.org, SPARQL - a W3C recommendation query for RDF databases - has become an important query language for querying the bioinformatics knowledge bases. Moreover, due to the diversity of users’ requests for extracting information from the RDF data as well as the lack of users’ knowledge about the exact value of each fact in the RDF databases, it is desirable to use the SPARQL query with regular expression patterns for querying the RDF data. To the best of our knowledge, there is currently no work that efficiently supports regular expression processing in SPARQL over RDF databases. Most of the existing techniques for processing regular expressions are designed for querying a text corpus, or only for supporting the matching over the paths in an RDF graph. Results In this paper, we propose a novel framework for supporting regular expression processing in SPARQL query. Our contributions can be summarized as follows. 1 We propose an efficient framework for processing SPARQL queries with regular expression patterns in RDF databases. 2 We propose a cost model in order to adapt the proposed framework in the existing query optimizers. 3 We build a prototype for the proposed framework in C++ and conduct extensive experiments demonstrating the efficiency and effectiveness of our technique. Conclusions Experiments with a full-blown RDF engine show that our framework outperforms the existing ones by up to two orders of magnitude in processing SPARQL queries with regular expression patterns.

Hessian regularization based non-negative matrix factorization for gene expression data clustering.

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Liu, Xiao; Shi, Jun; Wang, Congzhi

2015-01-01

Since a key step in the analysis of gene expression data is to detect groups of genes that have similar expression patterns, clustering technique is then commonly used to analyze gene expression data. Data representation plays an important role in clustering analysis. The non-negative matrix factorization (NMF) is a widely used data representation method with great success in machine learning. Although the traditional manifold regularization method, Laplacian regularization (LR), can improve the performance of NMF, LR still suffers from the problem of its weak extrapolating power. Hessian regularization (HR) is a newly developed manifold regularization method, whose natural properties make it more extrapolating, especially for small sample data. In this work, we propose the HR-based NMF (HR-NMF) algorithm, and then apply it to represent gene expression data for further clustering task. The clustering experiments are conducted on five commonly used gene datasets, and the results indicate that the proposed HR-NMF outperforms LR-based NMM and original NMF, which suggests the potential application of HR-NMF for gene expression data.

Imagining the truth and the moon: an electrophysiological study of abstract and concrete word processing.

Science.gov (United States)

Gullick, Margaret M; Mitra, Priya; Coch, Donna

2013-05-01

Previous event-related potential studies have indicated that both a widespread N400 and an anterior N700 index differential processing of concrete and abstract words, but the nature of these components in relation to concreteness and imagery has been unclear. Here, we separated the effects of word concreteness and task demands on the N400 and N700 in a single word processing paradigm with a within-subjects, between-tasks design and carefully controlled word stimuli. The N400 was larger to concrete words than to abstract words, and larger in the visualization task condition than in the surface task condition, with no interaction. A marked anterior N700 was elicited only by concrete words in the visualization task condition, suggesting that this component indexes imagery. These findings are consistent with a revised or extended dual coding theory according to which concrete words benefit from greater activation in both verbal and imagistic systems. Copyright © 2013 Society for Psychophysiological Research.

The persistence of the attentional bias to regularities in a changing environment.

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Yu, Ru Qi; Zhao, Jiaying

2015-10-01

The environment often is stable, but some aspects may change over time. The challenge for the visual system is to discover and flexibly adapt to the changes. We examined how attention is shifted in the presence of changes in the underlying structure of the environment. In six experiments, observers viewed four simultaneous streams of objects while performing a visual search task. In the first half of each experiment, the stream in the structured location contained regularities, the shapes in the random location were randomized, and gray squares appeared in two neutral locations. In the second half, the stream in the structured or the random location may change. In the first half of all experiments, visual search was facilitated in the structured location, suggesting that attention was consistently biased toward regularities. In the second half, this bias persisted in the structured location when no change occurred (Experiment 1), when the regularities were removed (Experiment 2), or when new regularities embedded in the original or novel stimuli emerged in the previously random location (Experiments 3 and 6). However, visual search was numerically but no longer reliably faster in the structured location when the initial regularities were removed and new regularities were introduced in the previously random location (Experiment 4), or when novel random stimuli appeared in the random location (Experiment 5). This suggests that the attentional bias was weakened. Overall, the results demonstrate that the attentional bias to regularities was persistent but also sensitive to changes in the environment.

Regularization Techniques for Linear Least-Squares Problems

KAUST Repository

Suliman, Mohamed

2016-04-01

Linear estimation is a fundamental branch of signal processing that deals with estimating the values of parameters from a corrupted measured data. Throughout the years, several optimization criteria have been used to achieve this task. The most astonishing attempt among theses is the linear least-squares. Although this criterion enjoyed a wide popularity in many areas due to its attractive properties, it appeared to suffer from some shortcomings. Alternative optimization criteria, as a result, have been proposed. These new criteria allowed, in one way or another, the incorporation of further prior information to the desired problem. Among theses alternative criteria is the regularized least-squares (RLS). In this thesis, we propose two new algorithms to find the regularization parameter for linear least-squares problems. In the constrained perturbation regularization algorithm (COPRA) for random matrices and COPRA for linear discrete ill-posed problems, an artificial perturbation matrix with a bounded norm is forced into the model matrix. This perturbation is introduced to enhance the singular value structure of the matrix. As a result, the new modified model is expected to provide a better stabilize substantial solution when used to estimate the original signal through minimizing the worst-case residual error function. Unlike many other regularization algorithms that go in search of minimizing the estimated data error, the two new proposed algorithms are developed mainly to select the artifcial perturbation bound and the regularization parameter in a way that approximately minimizes the mean-squared error (MSE) between the original signal and its estimate under various conditions. The first proposed COPRA method is developed mainly to estimate the regularization parameter when the measurement matrix is complex Gaussian, with centered unit variance (standard), and independent and identically distributed (i.i.d.) entries. Furthermore, the second proposed COPRA

The relationship between regular sports participation and vigilance in male and female adolescents.

Directory of Open Access Journals (Sweden)

Rafael Ballester

Full Text Available The present study investigated the relationship between regular sport participation (soccer and vigilance performance. Two groups of male and female adolescents differentiated in terms of their sport participation (athletes, n = 39, and non-athletes, n = 36 took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In the other session, participants completed the Psychomotor Vigilance Task (PVT to evaluate their vigilance performance. Perceived arousal prior to the task and motivation toward the task were also measured in the PVT session. The results revealed that athletes had better cardiovascular fitness and showed better performance in the PVT. However, correlation analyses did not show any significant relationship between cardiovascular fitness and performance in the PVT. Athletes showed larger scores in motivation and perceived arousal measures with respect to non-athletes, although, once again, these variables were not correlated with PVT performance. Gender differences were observed only in the Leger test, with males showing greater fitness level than females. The major outcome of this research points to a positive relationship between regular sport participation and vigilance during adolescence. This relationship did not seem to be influenced by gender, perceived arousal, motivation toward the task or cardiovascular fitness. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between physical activity and cognitive functioning.

A Variance Minimization Criterion to Feature Selection Using Laplacian Regularization.

Science.gov (United States)

He, Xiaofei; Ji, Ming; Zhang, Chiyuan; Bao, Hujun

2011-10-01

In many information processing tasks, one is often confronted with very high-dimensional data. Feature selection techniques are designed to find the meaningful feature subset of the original features which can facilitate clustering, classification, and retrieval. In this paper, we consider the feature selection problem in unsupervised learning scenarios, which is particularly difficult due to the absence of class labels that would guide the search for relevant information. Based on Laplacian regularized least squares, which finds a smooth function on the data manifold and minimizes the empirical loss, we propose two novel feature selection algorithms which aim to minimize the expected prediction error of the regularized regression model. Specifically, we select those features such that the size of the parameter covariance matrix of the regularized regression model is minimized. Motivated from experimental design, we use trace and determinant operators to measure the size of the covariance matrix. Efficient computational schemes are also introduced to solve the corresponding optimization problems. Extensive experimental results over various real-life data sets have demonstrated the superiority of the proposed algorithms.

The Role of Personality in a Regular Cognitive Monitoring Program.

Science.gov (United States)

Sadeq, Nasreen A; Valdes, Elise G; Harrison Bush, Aryn L; Andel, Ross

2018-02-20

This study examines the role of personality in cognitive performance, adherence, and satisfaction with regular cognitive self-monitoring. One hundred fifty-seven cognitively healthy older adults, age 55+, completed the 44-item Big-Five Inventory and were subsequently engaged in online monthly cognitive monitoring using the Cogstate Brief Battery for up to 35 months (M=14 mo, SD=7 mo). The test measures speed and accuracy in reaction time, visual learning, and working memory tasks. Neuroticism, although not related to cognitive performance overall (P>0.05), was related to a greater increase in accuracy (estimate=0.07, P=0.04) and speed (estimate=-0.09, P=0.03) on One Card Learning. Greater conscientiousness was related to faster overall speed on Detection (estimate=-1.62, P=0.02) and a significant rate of improvement in speed on One Card Learning (estimate=-0.10, Pconscientiousness were observed. Participants volunteering for regular cognitive monitoring may be quite uniform in terms of personality traits, with personality traits playing a relatively minor role in adherence and satisfaction. The more neurotic may exhibit better accuracy and improve in speed with time, whereas the more conscientious may perform faster overall and improve in speed on some tasks, but the effects appear small.

ABSTRACTION OF DRIFT SEEPAGE

International Nuclear Information System (INIS)

Wilson, Michael L.

2001-01-01

Drift seepage refers to flow of liquid water into repository emplacement drifts, where it can potentially contribute to degradation of the engineered systems and release and transport of radionuclides within the drifts. Because of these important effects, seepage into emplacement drifts is listed as a ''principal factor for the postclosure safety case'' in the screening criteria for grading of data in Attachment 1 of AP-3.15Q, Rev. 2, ''Managing Technical Product Inputs''. Abstraction refers to distillation of the essential components of a process model into a form suitable for use in total-system performance assessment (TSPA). Thus, the purpose of this analysis/model is to put the information generated by the seepage process modeling in a form appropriate for use in the TSPA for the Site Recommendation. This report also supports the Unsaturated-Zone Flow and Transport Process Model Report. The scope of the work is discussed below. This analysis/model is governed by the ''Technical Work Plan for Unsaturated Zone Flow and Transport Process Model Report'' (CRWMS MandO 2000a). Details of this activity are in Addendum A of the technical work plan. The original Work Direction and Planning Document is included as Attachment 7 of Addendum A. Note that the Work Direction and Planning Document contains tasks identified for both Performance Assessment Operations (PAO) and Natural Environment Program Operations (NEPO). Only the PAO tasks are documented here. The planning for the NEPO activities is now in Addendum D of the same technical work plan and the work is documented in a separate report (CRWMS MandO 2000b). The Project has been reorganized since the document was written. The responsible organizations in the new structure are the Performance Assessment Department and the Unsaturated Zone Department, respectively. The work plan for the seepage abstraction calls for determining an appropriate abstraction methodology, determining uncertainties in seepage, and providing

Toward an implicit measure of emotions: ratings of abstract images reveal distinct emotional states.

Science.gov (United States)

Bartoszek, Gregory; Cervone, Daniel

2017-11-01

Although implicit tests of positive and negative affect exist, implicit measures of distinct emotional states are scarce. Three experiments examined whether a novel implicit emotion-assessment task, the rating of emotion expressed in abstract images, would reveal distinct emotional states. In Experiment 1, participants exposed to a sadness-inducing story inferred more sadness, and less happiness, in abstract images. In Experiment 2, an anger-provoking interaction increased anger ratings. In Experiment 3, compared to neutral images, spider images increased fear ratings in spider-fearful participants but not in controls. In each experiment, the implicit task indicated elevated levels of the target emotion and did not indicate elevated levels of non-target negative emotions; the task thus differentiated among emotional states of the same valence. Correlations also supported the convergent and discriminant validity of the implicit task. Supporting the possibility that heuristic processes underlie the ratings, group differences were stronger among those who responded relatively quickly.

Task-based detectability in CT image reconstruction by filtered backprojection and penalized likelihood estimation

Energy Technology Data Exchange (ETDEWEB)

Gang, Grace J. [Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5G 2M9, Canada and Department of Biomedical Engineering, Johns Hopkins University, Baltimore Maryland 21205 (Canada); Stayman, J. Webster; Zbijewski, Wojciech [Department of Biomedical Engineering, Johns Hopkins University, Baltimore Maryland 21205 (United States); Siewerdsen, Jeffrey H., E-mail: jeff.siewerdsen@jhu.edu [Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5G 2M9, Canada and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 (United States)

2014-08-15

Purpose: Nonstationarity is an important aspect of imaging performance in CT and cone-beam CT (CBCT), especially for systems employing iterative reconstruction. This work presents a theoretical framework for both filtered-backprojection (FBP) and penalized-likelihood (PL) reconstruction that includes explicit descriptions of nonstationary noise, spatial resolution, and task-based detectability index. Potential utility of the model was demonstrated in the optimal selection of regularization parameters in PL reconstruction. Methods: Analytical models for local modulation transfer function (MTF) and noise-power spectrum (NPS) were investigated for both FBP and PL reconstruction, including explicit dependence on the object and spatial location. For FBP, a cascaded systems analysis framework was adapted to account for nonstationarity by separately calculating fluence and system gains for each ray passing through any given voxel. For PL, the point-spread function and covariance were derived using the implicit function theorem and first-order Taylor expansion according toFessler [“Mean and variance of implicitly defined biased estimators (such as penalized maximum likelihood): Applications to tomography,” IEEE Trans. Image Process. 5(3), 493–506 (1996)]. Detectability index was calculated for a variety of simple tasks. The model for PL was used in selecting the regularization strength parameter to optimize task-based performance, with both a constant and a spatially varying regularization map. Results: Theoretical models of FBP and PL were validated in 2D simulated fan-beam data and found to yield accurate predictions of local MTF and NPS as a function of the object and the spatial location. The NPS for both FBP and PL exhibit similar anisotropic nature depending on the pathlength (and therefore, the object and spatial location within the object) traversed by each ray, with the PL NPS experiencing greater smoothing along directions with higher noise. The MTF of FBP

Multi-task Vector Field Learning.

Science.gov (United States)

Lin, Binbin; Yang, Sen; Zhang, Chiyuan; Ye, Jieping; He, Xiaofei

2012-01-01

Multi-task learning (MTL) aims to improve generalization performance by learning multiple related tasks simultaneously and identifying the shared information among tasks. Most of existing MTL methods focus on learning linear models under the supervised setting. We propose a novel semi-supervised and nonlinear approach for MTL using vector fields. A vector field is a smooth mapping from the manifold to the tangent spaces which can be viewed as a directional derivative of functions on the manifold. We argue that vector fields provide a natural way to exploit the geometric structure of data as well as the shared differential structure of tasks, both of which are crucial for semi-supervised multi-task learning. In this paper, we develop multi-task vector field learning (MTVFL) which learns the predictor functions and the vector fields simultaneously. MTVFL has the following key properties. (1) The vector fields MTVFL learns are close to the gradient fields of the predictor functions. (2) Within each task, the vector field is required to be as parallel as possible which is expected to span a low dimensional subspace. (3) The vector fields from all tasks share a low dimensional subspace. We formalize our idea in a regularization framework and also provide a convex relaxation method to solve the original non-convex problem. The experimental results on synthetic and real data demonstrate the effectiveness of our proposed approach.

The Neural Correlates of Abstract and Concrete Words: Evidence from Brain-Damaged Patients

OpenAIRE

Papagno, Costanza; Martello, Giorgia; Mattavelli, Giulia

2013-01-01

Neuropsychological and activation studies on the neural correlates of abstract and concrete words have produced contrasting results. The present study explores the anatomical substrates of abstract/concrete words in 22 brain-damaged patients with a single vascular lesion either in the right or left hemisphere. One hundred and twenty (60 concrete and 60 abstract) noun triplets were used for a semantic similarity judgment task. We found a significant interaction in word type × group since left ...

Affective priming using facial expressions modulates liking for abstract art.

Science.gov (United States)

Flexas, Albert; Rosselló, Jaume; Christensen, Julia F; Nadal, Marcos; Olivera La Rosa, Antonio; Munar, Enric

2013-01-01

We examined the influence of affective priming on the appreciation of abstract artworks using an evaluative priming task. Facial primes (showing happiness, disgust or no emotion) were presented under brief (Stimulus Onset Asynchrony, SOA = 20 ms) and extended (SOA = 300 ms) conditions. Differences in aesthetic liking for abstract paintings depending on the emotion expressed in the preceding primes provided a measure of the priming effect. The results showed that, for the extended SOA, artworks were liked more when preceded by happiness primes and less when preceded by disgust primes. Facial expressions of happiness, though not of disgust, exerted similar effects in the brief SOA condition. Subjective measures and a forced-choice task revealed no evidence of prime awareness in the suboptimal condition. Our results are congruent with findings showing that the affective transfer elicited by priming biases evaluative judgments, extending previous research to the domain of aesthetic appreciation.

Affective priming using facial expressions modulates liking for abstract art.

Directory of Open Access Journals (Sweden)

Albert Flexas

Full Text Available We examined the influence of affective priming on the appreciation of abstract artworks using an evaluative priming task. Facial primes (showing happiness, disgust or no emotion were presented under brief (Stimulus Onset Asynchrony, SOA = 20 ms and extended (SOA = 300 ms conditions. Differences in aesthetic liking for abstract paintings depending on the emotion expressed in the preceding primes provided a measure of the priming effect. The results showed that, for the extended SOA, artworks were liked more when preceded by happiness primes and less when preceded by disgust primes. Facial expressions of happiness, though not of disgust, exerted similar effects in the brief SOA condition. Subjective measures and a forced-choice task revealed no evidence of prime awareness in the suboptimal condition. Our results are congruent with findings showing that the affective transfer elicited by priming biases evaluative judgments, extending previous research to the domain of aesthetic appreciation.

“Bear-ly” learning: Limits of abstraction in black bear cognition

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Jennifer Vonk

2018-02-01

Full Text Available We presented two American black bears (Ursus americanus with a serial list learning memory task, and one of the bears with a matching-to-sample task. After extended training, both bears demonstrated some success with the memory task but failed to generalize the overarching rule of the task to novel stimuli. Matching to sample proved even more difficult for our bear to learn. We conclude that, despite previous success in training bears to respond to natural categories, quantity discriminations, and other related tasks, that bears may possess a cognitive limitation with regards to learning abstract rules. Future tests using different procedures are necessary to determine whether this is a limit of bears’ cognitive capacities, or a limitation of the current tasks as presented. Future tests should present a larger number of varying stimuli. Ideally, bears of various species should be tested on these tasks to demonstrate species as well as individual differences.

Advantages and disadvantages of intraoperative language tasks in awake surgery: a three-task approach for prefrontal tumors.

Science.gov (United States)

Rofes, A; Spena, G; Miozzo, A; Fontanella, M M; Miceli, G

2015-12-01

Multidisciplinary efforts are being made to provide surgical teams with sensitive and specific tasks for language mapping in awake surgery. Researchers and clinicians have elaborated different tasks over time. A fair amount of work has been directed to study the neurofunctional correlates of some of these tasks, and there is recent interest in their standardization. However, little discussion exists on the advantages and disadvantages that each task poses from the perspective of the cognitive neuroscience of language. Such an approach may be a relevant step to assess task validity, to avoid using tasks that tap onto similar processes, and to provide patients with a surgical treatment that ensures maximal tumor resection while avoiding postoperative language deficits. An understanding of the language components that each task entails may also be relevant to improve the current assessments and the ways in which tasks are administered, and to disentangle neurofunctional questions. We reviewed 17 language mapping tasks that have been used in awake surgery. Overt production tasks have been a preferred choice over comprehension tasks. Tasks tapping lexico-semantic processes, particularly object-naming, maintain their role as gold standards. Automated speech tasks are used to detect speech errors and to set the amplitude of the stimulator. Comprehension tasks, reading and writing tasks, and tasks that assess grammatical aspects of language may be regularly administered in the near future. We provide examples of a three-task approach we are administering to patients with prefrontal lesions. We believe that future advances in this area are contingent upon reviewing gold standards and introducing new assessment tools.

Working memory and the control of action: evidence from task switching.

Science.gov (United States)

Baddeley, A; Chincotta, D; Adlam, A

2001-12-01

A series of 7 experiments used dual-task methodology to investigate the role of working memory in the operation of a simple action-control plan or program involving regular switching between addition and subtraction. Lists requiring switching were slower than blocked lists and showed 2 concurrent task effects. Demanding executive tasks impaired performance on both blocked and switched lists, whereas articulatory suppression impaired principally the switched condition. Implications for models of task switching and working memory and for the Vygotskian concept of verbal control of action are discussed.

Distance-regular graphs

NARCIS (Netherlands)

van Dam, Edwin R.; Koolen, Jack H.; Tanaka, Hajime

2016-01-01

This is a survey of distance-regular graphs. We present an introduction to distance-regular graphs for the reader who is unfamiliar with the subject, and then give an overview of some developments in the area of distance-regular graphs since the monograph 'BCN'[Brouwer, A.E., Cohen, A.M., Neumaier,

Are factors related to dual-task performance in people with Parkinson's disease dependent on the type of dual task?

Science.gov (United States)

Strouwen, Carolien; Molenaar, Esther A L M; Keus, Samyra H J; Münks, Liesbeth; Heremans, Elke; Vandenberghe, Wim; Bloem, Bastiaan R; Nieuwboer, Alice

2016-02-01

Impaired dual-task performance significantly impacts upon functional mobility in people with Parkinson's disease (PD). The aim of this study was to identify determinants of dual-task performance in people with PD in three different dual tasks to assess their possible task-dependency. We recruited 121 home-dwelling patients with PD (mean age 65.93 years; mean disease duration 8.67 years) whom we subjected to regular walking (control condition) and to three dual-task conditions: walking combined with a backwards Digit Span task, an auditory Stroop task and a Mobile Phone task. We measured dual-task gait velocity using the GAITRite mat and dual-task reaction times and errors on the concurrent tasks as outcomes. Motor, cognitive and descriptive variables which correlated to dual-task performance (p task gait velocity and executive function, tested by the alternating intake test, was significantly associated with gait velocity during the Digit Span (R(2) = 0.65; p task (R(2) = 0.62; p task. Age was a surplus determinant of gait velocity while using a mobile phone. Single-task gait velocity and executive function as measured by a verbal fluency switching task were independent determinants of dual-task gait performance in people with PD. In contrast to expectation, these factors were the same across different tasks, supporting the robustness of the findings. Future study needs to determine whether these factors predict dual-task abnormalities prospectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Contextual analysis of Biology and Chemistry academic graphical abstracts

Directory of Open Access Journals (Sweden)

Cristiane Salete Florek

2016-10-01

Full Text Available http://dx.doi.org/10.5007/1984-8412.2016v13n3p1363 The Graphical Abstract (GA is a non-regular discursive practice held in the academic context, and that, when occurs, coexists with the academic abstract (AA in the table of contents of scientific journals, and in HTML versions of academic articles, materializing by the combination of the verbal and visual semiotics. In this paper, in the light of the Critical Analysis genres (MEURER, 2002; BHATIA, 2004; MOTTA-ROTH, 2006, 2008, which allow us to study a text based on the investigation of its context’s critical research, we present the results of the contextual analysis of GAs in the areas of Biology and Chemistry. This analysis was done by: i interviews with researchers of the investigated areas; and ii documentary analysis. Results show that, in general, GA: i is highlighted by presenting an advertising nature, which seeks to attract the reader’s attention; ii: summarizes the topic and the main findings of scientific research; and iii does not replace the academia abstract (AA.

SAR image regularization with fast approximate discrete minimization.

Science.gov (United States)

Denis, Loïc; Tupin, Florence; Darbon, Jérôme; Sigelle, Marc

2009-07-01

Synthetic aperture radar (SAR) images, like other coherent imaging modalities, suffer from speckle noise. The presence of this noise makes the automatic interpretation of images a challenging task and noise reduction is often a prerequisite for successful use of classical image processing algorithms. Numerous approaches have been proposed to filter speckle noise. Markov random field (MRF) modelization provides a convenient way to express both data fidelity constraints and desirable properties of the filtered image. In this context, total variation minimization has been extensively used to constrain the oscillations in the regularized image while preserving its edges. Speckle noise follows heavy-tailed distributions, and the MRF formulation leads to a minimization problem involving nonconvex log-likelihood terms. Such a minimization can be performed efficiently by computing minimum cuts on weighted graphs. Due to memory constraints, exact minimization, although theoretically possible, is not achievable on large images required by remote sensing applications. The computational burden of the state-of-the-art algorithm for approximate minimization (namely the alpha -expansion) is too heavy specially when considering joint regularization of several images. We show that a satisfying solution can be reached, in few iterations, by performing a graph-cut-based combinatorial exploration of large trial moves. This algorithm is applied to joint regularization of the amplitude and interferometric phase in urban area SAR images.

LL-regular grammars

NARCIS (Netherlands)

Nijholt, Antinus

1980-01-01

Culik II and Cogen introduced the class of LR-regular grammars, an extension of the LR(k) grammars. In this paper we consider an analogous extension of the LL(k) grammars called the LL-regular grammars. The relation of this class of grammars to other classes of grammars will be shown. Any LL-regular

Contributions of Lateral and Orbital Frontal Regions to Abstract Rule Acquisition and Reversal in Monkeys

Science.gov (United States)

La Camera, Giancarlo; Bouret, Sebastien; Richmond, Barry J.

2018-01-01

The ability to learn and follow abstract rules relies on intact prefrontal regions including the lateral prefrontal cortex (LPFC) and the orbitofrontal cortex (OFC). Here, we investigate the specific roles of these brain regions in learning rules that depend critically on the formation of abstract concepts as opposed to simpler input-output associations. To this aim, we tested monkeys with bilateral removals of either LPFC or OFC on a rapidly learned task requiring the formation of the abstract concept of same vs. different. While monkeys with OFC removals were significantly slower than controls at both acquiring and reversing the concept-based rule, monkeys with LPFC removals were not impaired in acquiring the task, but were significantly slower at rule reversal. Neither group was impaired in the acquisition or reversal of a delayed visual cue-outcome association task without a concept-based rule. These results suggest that OFC is essential for the implementation of a concept-based rule, whereas LPFC seems essential for its modification once established. PMID:29615854

Verbal Working Memory Is Related to the Acquisition of Cross-Linguistic Phonological Regularities.

Science.gov (United States)

Bosma, Evelyn; Heeringa, Wilbert; Hoekstra, Eric; Versloot, Arjen; Blom, Elma

2017-01-01

Closely related languages share cross-linguistic phonological regularities, such as Frisian -âld [ͻ:t] and Dutch -oud [ʱut], as in the cognate pairs kâld [kͻ:t] - koud [kʱut] 'cold' and wâld [wͻ:t] - woud [wʱut] 'forest'. Within Bybee's (1995, 2001, 2008, 2010) network model, these regularities are, just like grammatical rules within a language, generalizations that emerge from schemas of phonologically and semantically related words. Previous research has shown that verbal working memory is related to the acquisition of grammar, but not vocabulary. This suggests that verbal working memory supports the acquisition of linguistic regularities. In order to test this hypothesis we investigated whether verbal working memory is also related to the acquisition of cross-linguistic phonological regularities. For three consecutive years, 5- to 8-year-old Frisian-Dutch bilingual children ( n = 120) were tested annually on verbal working memory and a Frisian receptive vocabulary task that comprised four cognate categories: (1) identical cognates, (2) non-identical cognates that either do or (3) do not exhibit a phonological regularity between Frisian and Dutch, and (4) non-cognates. The results showed that verbal working memory had a significantly stronger effect on cognate category (2) than on the other three cognate categories. This suggests that verbal working memory is related to the acquisition of cross-linguistic phonological regularities. More generally, it confirms the hypothesis that verbal working memory plays a role in the acquisition of linguistic regularities.

Evidence for the Modulation of Sub-Lexical Processing in Go No-Go Naming: The Elimination of the Frequency x Regularity Interaction

Science.gov (United States)

Cummine, Jacqueline; Amyotte, Josee; Pancheshen, Brent; Chouinard, Brea

2011-01-01

The Frequency (high vs. low) x Regularity (regular vs. exception) interaction found on naming response times is often taken as evidence for parallel processing of sub-lexical and lexical systems. Using a Go/No-go naming task, we investigated the effect of nonword versus pseudohomophone foils on sub-lexical processing and the subsequent Frequency x…

Graded effects of regularity in language revealed by N400 indices of morphological priming.

Science.gov (United States)

Kielar, Aneta; Joanisse, Marc F

2010-07-01

Differential electrophysiological effects for regular and irregular linguistic forms have been used to support the theory that grammatical rules are encoded using a dedicated cognitive mechanism. The alternative hypothesis is that language systematicities are encoded probabilistically in a way that does not categorically distinguish rule-like and irregular forms. In the present study, this matter was investigated more closely by focusing specifically on whether the regular-irregular distinction in English past tenses is categorical or graded. We compared the ERP priming effects of regulars (baked-bake), vowel-change irregulars (sang-sing), and "suffixed" irregulars that display a partial regularity (suffixed irregular verbs, e.g., slept-sleep), as well as forms that are related strictly along formal or semantic dimensions. Participants performed a visual lexical decision task with either visual (Experiment 1) or auditory prime (Experiment 2). Stronger N400 priming effects were observed for regular than vowel-change irregular verbs, whereas suffixed irregulars tended to group with regular verbs. Subsequent analyses decomposed early versus late-going N400 priming, and suggested that differences among forms can be attributed to the orthographic similarity of prime and target. Effects of morphological relatedness were observed in the later-going time period, however, we failed to observe true regular-irregular dissociations in either experiment. The results indicate that morphological effects emerge from the interaction of orthographic, phonological, and semantic overlap between words.

Auditory Stimulus Processing and Task Learning Are Adequate in Dyslexia, but Benefits from Regularities Are Reduced

Science.gov (United States)

Daikhin, Luba; Raviv, Ofri; Ahissar, Merav

2017-01-01

Purpose: The reading deficit for people with dyslexia is typically associated with linguistic, memory, and perceptual-discrimination difficulties, whose relation to reading impairment is disputed. We proposed that automatic detection and usage of serial sound regularities for individuals with dyslexia is impaired (anchoring deficit hypothesis),…

Retrieval-based Face Annotation by Weak Label Regularized Local Coordinate Coding.

Science.gov (United States)

Wang, Dayong; Hoi, Steven C H; He, Ying; Zhu, Jianke; Mei, Tao; Luo, Jiebo

2013-08-02

Retrieval-based face annotation is a promising paradigm of mining massive web facial images for automated face annotation. This paper addresses a critical problem of such paradigm, i.e., how to effectively perform annotation by exploiting the similar facial images and their weak labels which are often noisy and incomplete. In particular, we propose an effective Weak Label Regularized Local Coordinate Coding (WLRLCC) technique, which exploits the principle of local coordinate coding in learning sparse features, and employs the idea of graph-based weak label regularization to enhance the weak labels of the similar facial images. We present an efficient optimization algorithm to solve the WLRLCC task. We conduct extensive empirical studies on two large-scale web facial image databases: (i) a Western celebrity database with a total of $6,025$ persons and $714,454$ web facial images, and (ii)an Asian celebrity database with $1,200$ persons and $126,070$ web facial images. The encouraging results validate the efficacy of the proposed WLRLCC algorithm. To further improve the efficiency and scalability, we also propose a PCA-based approximation scheme and an offline approximation scheme (AWLRLCC), which generally maintains comparable results but significantly saves much time cost. Finally, we show that WLRLCC can also tackle two existing face annotation tasks with promising performance.

Conceiving Education: The Creative Task before Us

Science.gov (United States)

Laverty, Megan J.

2014-01-01

Philosophers of education regularly undertake the challenging task of defining their field and what it is they do. John White and Harvey Siegel are no exception: Siegel categorizes philosophy of education as a branch of philosophy, and White responds that philosophers of education would do better to adopt a Deweyan perspective. White claims that…

High Neuromagnetic Activation in the Left Prefrontal and Frontal Cortices Correlates with Better Memory Performance for Abstract Words

Science.gov (United States)

Chen, Tzu-Ching; Lin, Yung-Yang

2012-01-01

The present study aimed to clarify the spatiotemporal characteristics of memory processing for abstract and concrete words. Neuromagnetic responses to memory encoding and recognition tasks of abstract and concrete nouns were obtained in 18 healthy adults using a whole-head neuromagnetometer. During memory encoding, abstract words elicited larger…

Automatic Probabilistic Program Verification through Random Variable Abstraction

Directory of Open Access Journals (Sweden)

Damián Barsotti

2010-06-01

Full Text Available The weakest pre-expectation calculus has been proved to be a mature theory to analyze quantitative properties of probabilistic and nondeterministic programs. We present an automatic method for proving quantitative linear properties on any denumerable state space using iterative backwards fixed point calculation in the general framework of abstract interpretation. In order to accomplish this task we present the technique of random variable abstraction (RVA and we also postulate a sufficient condition to achieve exact fixed point computation in the abstract domain. The feasibility of our approach is shown with two examples, one obtaining the expected running time of a probabilistic program, and the other the expected gain of a gambling strategy. Our method works on general guarded probabilistic and nondeterministic transition systems instead of plain pGCL programs, allowing us to easily model a wide range of systems including distributed ones and unstructured programs. We present the operational and weakest precondition semantics for this programs and prove its equivalence.

Single neurons in prefrontal cortex encode abstract rules.

Science.gov (United States)

Wallis, J D; Anderson, K C; Miller, E K

2001-06-21

The ability to abstract principles or rules from direct experience allows behaviour to extend beyond specific circumstances to general situations. For example, we learn the 'rules' for restaurant dining from specific experiences and can then apply them in new restaurants. The use of such rules is thought to depend on the prefrontal cortex (PFC) because its damage often results in difficulty in following rules. Here we explore its neural basis by recording from single neurons in the PFC of monkeys trained to use two abstract rules. They were required to indicate whether two successively presented pictures were the same or different depending on which rule was currently in effect. The monkeys performed this task with new pictures, thus showing that they had learned two general principles that could be applied to stimuli that they had not yet experienced. The most prevalent neuronal activity observed in the PFC reflected the coding of these abstract rules.

Estimating Demand and Cross-Price Elasticity for Very Low Nicotine Content (VLNC) Cigarettes Using a Simulated Demand Task.

Science.gov (United States)

Tucker, Megan R; Laugesen, Murray; Grace, Randolph C

2017-03-03

Very Low Nicotine Content (VLNC) cigarettes might be useful as part of a tobacco control strategy, but relatively little is known about their acceptability as substitutes for regular cigarettes. We compared subjective effects and demand for regular cigarettes and Very Low Nicotine Content (VLNC) cigarettes, and estimated cross-price elasticity for VLNC cigarettes, using simulated demand tasks. 40 New Zealand smokers sampled a VLNC cigarette and completed Cigarette Purchase Tasks to indicate their demand for regular cigarettes and VLNC cigarettes at a range of prices, and a cross-price task indicating how many regular cigarettes and VLNC cigarettes they would purchase at 0.5x, 1x, and 2x the current market price for regular cigarettes, assuming the price of VLNC cigarettes remained constant. They also rated the subjective effects of the VLNC cigarette and their usual-brand regular cigarettes. Cross-price elasticity for VLNC cigarettes was estimated as 0.24 and was significantly positive, indicating that VLNC cigarettes are partially substitutable for regular cigarettes. VLNC cigarettes were rated as less satisfying and psychologically rewarding than regular cigarettes, but this was unrelated to demand or substitutability. VLNC cigarettes are potentially substitutable for regular cigarettes. Their availability may reduce tobacco consumption, nicotine intake and addiction; making it easier for smokers to quit. VLNC cigarettes share the behavioural and sensory components of smoking whilst delivering negligible levels of nicotine. Although smokers rated VLNCs as less satisfying than regular cigarettes, smokers said they would increase their consumption of VLNCs as the price of regular cigarettes increased, if VLNCs were available at a lower price. This suggests that VLNCs are partially substitutable for regular cigarettes. VLNCs can be part of an effective tobacco control strategy, by reducing nicotine dependence and improving health and financial outcomes for smokers

An iterative method for Tikhonov regularization with a general linear regularization operator

NARCIS (Netherlands)

Hochstenbach, M.E.; Reichel, L.

2010-01-01

Tikhonov regularization is one of the most popular approaches to solve discrete ill-posed problems with error-contaminated data. A regularization operator and a suitable value of a regularization parameter have to be chosen. This paper describes an iterative method, based on Golub-Kahan

Regularization of the double period method for experimental data processing

Science.gov (United States)

Belov, A. A.; Kalitkin, N. N.

2017-11-01

In physical and technical applications, an important task is to process experimental curves measured with large errors. Such problems are solved by applying regularization methods, in which success depends on the mathematician's intuition. We propose an approximation based on the double period method developed for smooth nonperiodic functions. Tikhonov's stabilizer with a squared second derivative is used for regularization. As a result, the spurious oscillations are suppressed and the shape of an experimental curve is accurately represented. This approach offers a universal strategy for solving a broad class of problems. The method is illustrated by approximating cross sections of nuclear reactions important for controlled thermonuclear fusion. Tables recommended as reference data are obtained. These results are used to calculate the reaction rates, which are approximated in a way convenient for gasdynamic codes. These approximations are superior to previously known formulas in the covered temperature range and accuracy.

Some tasks of the IBTE | Ruud | Zede Journal

African Journals Online (AJOL)

Some tasks of the IBTE. H Ruud. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms ...

Low-level radioactive waste from commercial nuclear reactors. Volume 3. Bibliographic abstracts of significant source documents. Part 1. Open-literature abstracts for low-level radioactive waste

International Nuclear Information System (INIS)

Bowers, M.K.; Rodgers, B.R.; Jolley, R.L.

1986-05-01

The overall task of this program was to provide an assessment of currently available technology for treating commercial low-level radioactive waste (LLRW), to initiate development of a methodology for choosing one technology for a given application, and to identify research needed to improve current treatment techniques and decision methodology. The resulting report is issued in four volumes. Volume 3 of this series is a collection of abstracts of most of the reference documents used for this study. Because of the large volume of literature, the abstracts have been printed in two separate parts. Volume 3, part 1 presents abstracts of the open literature relating to LLRW treatment methodologies. Some of these references pertain to treatment processes for hazardous wastes that may also be applicable to LLRW management. All abstracts have been limited to 21 lines (for brevity), but each abstract contains sufficient information to enable the reader to determine the potential usefulness of the source document and to locate each article. The abstracts are arranged alphabetically by author or organization, and indexed by keyword

Low-level radioactive waste from commercial nuclear reactors. Volume 3. Bibliographic abstracts of significant source documents. Part 1. Open-literature abstracts for low-level radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Bowers, M.K.; Rodgers, B.R.; Jolley, R.L.

1986-05-01

The overall task of this program was to provide an assessment of currently available technology for treating commercial low-level radioactive waste (LLRW), to initiate development of a methodology for choosing one technology for a given application, and to identify research needed to improve current treatment techniques and decision methodology. The resulting report is issued in four volumes. Volume 3 of this series is a collection of abstracts of most of the reference documents used for this study. Because of the large volume of literature, the abstracts have been printed in two separate parts. Volume 3, part 1 presents abstracts of the open literature relating to LLRW treatment methodologies. Some of these references pertain to treatment processes for hazardous wastes that may also be applicable to LLRW management. All abstracts have been limited to 21 lines (for brevity), but each abstract contains sufficient information to enable the reader to determine the potential usefulness of the source document and to locate each article. The abstracts are arranged alphabetically by author or organization, and indexed by keyword.

The-Abstraction-Hierarchy-based Mobile PC Display Design for NPP Maintenance

International Nuclear Information System (INIS)

Kim, In; Kim, Bo Gyung; Seong, Poong Hyun; Ha, Jun Su

2010-01-01

Recently, the importance of effective maintenance in nuclear power plants (NPPs) has been emphasized and research into effective maintenance by adopting mobile maintenance aids (MMAs) have been attempted. For improved and effective use of an MMA display design method based on abstraction hierarchy (AH) is proposed and its design considerations are discussed in this study. Six levels of abstraction hierarchy are proposed in this paper to classify the maintenance information. By classifying and organizing maintenance information using AH, maintenance information can be used effectively by users with either high or low levels of expertise. When information classification has been finished, the information for MMA design is selected and designed. With the considerations of MMA design analysis and guidelines, AH-based MMA is designed for the maintenance tasks. An experiment is conducted using the AH-based MMA in order to estimate the effectiveness of the proposed method for the maintenance tasks and to identify design considerations to enhance the proposed MMAs. The result indicated that an AH-based manual was more effective than a conventional manual in terms of task completion time and number of errors. The workload for the AH-based manual was estimated less than the conventional manual for subjects with low level of expertise. As the level of expertise increases, subjects tended to follow more abstract information while the number of navigations decreased. It is believed that when mobile devices become pervasive in NPP maintenance fields, AH-model applied MMAs can be used as an effective maintenance supporting tool

Written Spelling to Dictation: Sound-To-Spelling Regularity Affects Both Writing Latencies and Durations

Science.gov (United States)

Delattre, Marie; Bonin, Patrick; Barry, Christopher

2006-01-01

The authors examined the effect of sound-to-spelling regularity on written spelling latencies and writing durations in a dictation task in which participants had to write each target word 3 times in succession. The authors found that irregular words (i.e., those containing low-probability phoneme-to-grapheme mappings) were slower both to…

Regular Expression Pocket Reference

CERN Document Server

Stubblebine, Tony

2007-01-01

This handy little book offers programmers a complete overview of the syntax and semantics of regular expressions that are at the heart of every text-processing application. Ideal as a quick reference, Regular Expression Pocket Reference covers the regular expression APIs for Perl 5.8, Ruby (including some upcoming 1.9 features), Java, PHP, .NET and C#, Python, vi, JavaScript, and the PCRE regular expression libraries. This concise and easy-to-use reference puts a very powerful tool for manipulating text and data right at your fingertips. Composed of a mixture of symbols and text, regular exp

Verbal Working Memory Is Related to the Acquisition of Cross-Linguistic Phonological Regularities

Directory of Open Access Journals (Sweden)

Evelyn Bosma

2017-09-01

Full Text Available Closely related languages share cross-linguistic phonological regularities, such as Frisian -âld [ͻ:t] and Dutch -oud [ʱut], as in the cognate pairs kâld [kͻ:t] – koud [kʱut] ‘cold’ and wâld [wͻ:t] – woud [wʱut] ‘forest’. Within Bybee’s (1995, 2001, 2008, 2010 network model, these regularities are, just like grammatical rules within a language, generalizations that emerge from schemas of phonologically and semantically related words. Previous research has shown that verbal working memory is related to the acquisition of grammar, but not vocabulary. This suggests that verbal working memory supports the acquisition of linguistic regularities. In order to test this hypothesis we investigated whether verbal working memory is also related to the acquisition of cross-linguistic phonological regularities. For three consecutive years, 5- to 8-year-old Frisian-Dutch bilingual children (n = 120 were tested annually on verbal working memory and a Frisian receptive vocabulary task that comprised four cognate categories: (1 identical cognates, (2 non-identical cognates that either do or (3 do not exhibit a phonological regularity between Frisian and Dutch, and (4 non-cognates. The results showed that verbal working memory had a significantly stronger effect on cognate category (2 than on the other three cognate categories. This suggests that verbal working memory is related to the acquisition of cross-linguistic phonological regularities. More generally, it confirms the hypothesis that verbal working memory plays a role in the acquisition of linguistic regularities.

From Abstract Art to Abstracted Artists

Directory of Open Access Journals (Sweden)

Romi Mikulinsky

2016-11-01

Full Text Available What lineage connects early abstract films and machine-generated YouTube videos? Hans Richter’s famous piece Rhythmus 21 is considered to be the first abstract film in the experimental tradition. The Webdriver Torso YouTube channel is composed of hundreds of thousands of machine-generated test patterns designed to check frequency signals on YouTube. This article discusses geometric abstraction vis-à-vis new vision, conceptual art and algorithmic art. It argues that the Webdriver Torso is an artistic marvel indicative of a form we call mathematical abstraction, which is art performed by computers and, quite possibly, for computers.

2-regularity and 2-normality conditions for systems with impulsive controls

Directory of Open Access Journals (Sweden)

Pavlova Natal'ya

2007-01-01

Full Text Available In this paper a controlled system with impulsive controls in the neighborhood of an abnormal point is investigated. The set of pairs (u,μ is considered as a class of admissible controls, where u is a measurable essentially bounded function and μ is a finite-dimensional Borel measure, such that for any Borel set B, μ(B is a subset of the given convex closed pointed cone. In this article the concepts of 2-regularity and 2-normality for the abstract mapping Ф, operating from the given Banach space into a finite-dimensional space, are introduced. The concepts of 2-regularity and 2-normality play a great role in the course of derivation of the first and the second order necessary conditions for the optimal control problem, consisting of the minimization of a certain functional on the set of the admissible processes. These concepts are also important for obtaining the sufficient conditions for the local controllability of the nonlinear systems. The convenient criterion for 2-regularity along the prescribed direction and necessary conditions for 2-normality of systems, linear in control, are introduced in this article as well.

Manipulating Objects and Telling Words: A Study on Concrete and Abstract Words Acquisition

Science.gov (United States)

Borghi, Anna M.; Flumini, Andrea; Cimatti, Felice; Marocco, Davide; Scorolli, Claudia

2011-01-01

Four experiments (E1–E2–E3–E4) investigated whether different acquisition modalities lead to the emergence of differences typically found between concrete and abstract words, as argued by the words as tools (WAT) proposal. To mimic the acquisition of concrete and abstract concepts, participants either manipulated novel objects or observed groups of objects interacting in novel ways (Training 1). In TEST 1 participants decided whether two elements belonged to the same category. Later they read the category labels (Training 2); labels could be accompanied by an explanation of their meaning. Then participants observed previously seen exemplars and other elements, and were asked which of them could be named with a given label (TEST 2). Across the experiments, it was more difficult to form abstract than concrete categories (TEST 1); even when adding labels, abstract words remained more difficult than concrete words (TEST 2). TEST 3 differed across the experiments. In E1 participants performed a feature production task. Crucially, the associations produced with the novel words reflected the pattern evoked by existing concrete and abstract words, as the first evoked more perceptual properties. In E2–E3–E4, TEST 3 consisted of a color verification task with manual/verbal (keyboard–microphone) responses. Results showed the microphone use to have an advantage over keyboard use for abstract words, especially in the explanation condition. This supports WAT: due to their acquisition modality, concrete words evoke more manual information; abstract words elicit more verbal information. This advantage was not present when linguistic information contrasted with perceptual one. Implications for theories and computational models of language grounding are discussed. PMID:21716582

Gait disorders in the elderly and dual task gait analysis: a new approach for identifying motor phenotypes.

Science.gov (United States)

Auvinet, Bernard; Touzard, Claude; Montestruc, François; Delafond, Arnaud; Goeb, Vincent

2017-01-31

Gait disorders and gait analysis under single and dual-task conditions are topics of great interest, but very few studies have looked for the relevance of gait analysis under dual-task conditions in elderly people on the basis of a clinical approach. An observational study including 103 patients (mean age 76.3 ± 7.2, women 56%) suffering from gait disorders or memory impairment was conducted. Gait analysis under dual-task conditions was carried out for all patients. Brain MRI was performed in the absence of contra-indications. Three main gait variables were measured: walking speed, stride frequency, and stride regularity. For each gait variable, the dual task cost was computed and a quartile analysis was obtained. Nonparametric tests were used for all the comparisons (Wilcoxon, Kruskal-Wallis, Fisher or Chi 2 tests). Four clinical subgroups were identified: gait instability (45%), recurrent falls (29%), memory impairment (18%), and cautious gait (8%). The biomechanical severity of these subgroups was ordered according to walking speed and stride regularity under both conditions, from least to most serious as follows: memory impairment, gait instability, recurrent falls, cautious gait (p < 0.01 for walking speed, p = 0.05 for stride regularity). According to the established diagnoses of gait disorders, 5 main pathological subgroups were identified (musculoskeletal diseases (n = 11), vestibular diseases (n = 6), mild cognitive impairment (n = 24), central nervous system pathologies, (n = 51), and without diagnosis (n = 8)). The dual task cost for walking speed, stride frequency and stride regularity were different among these subgroups (p < 0.01). The subgroups mild cognitive impairment and central nervous system pathologies both showed together a higher dual task cost for each variable compared to the other subgroups combined (p = 0.01). The quartile analysis of dual task cost for stride frequency and stride regularity

The method of abstraction in the design of databases and the interoperability

Science.gov (United States)

Yakovlev, Nikolay

2018-03-01

When designing the database structure oriented to the contents of indicators presented in the documents and communications subject area. First, the method of abstraction is applied by expansion of the indices of new, artificially constructed abstract concepts. The use of abstract concepts allows to avoid registration of relations many-to-many. For this reason, when built using abstract concepts, demonstrate greater stability in the processes. The example abstract concepts to address structure - a unique house number. Second, the method of abstraction can be used in the transformation of concepts by omitting some attributes that are unnecessary for solving certain classes of problems. Data processing associated with the amended concepts is more simple without losing the possibility of solving the considered classes of problems. For example, the concept "street" loses the binding to the land. The content of the modified concept of "street" are only the relations of the houses to the declared name. For most accounting tasks and ensure communication is enough.

Implicit Regularization for Reconstructing 3D Building Rooftop Models Using Airborne LiDAR Data

Directory of Open Access Journals (Sweden)

Jaewook Jung

2017-03-01

Full Text Available With rapid urbanization, highly accurate and semantically rich virtualization of building assets in 3D become more critical for supporting various applications, including urban planning, emergency response and location-based services. Many research efforts have been conducted to automatically reconstruct building models at city-scale from remotely sensed data. However, developing a fully-automated photogrammetric computer vision system enabling the massive generation of highly accurate building models still remains a challenging task. One the most challenging task for 3D building model reconstruction is to regularize the noises introduced in the boundary of building object retrieved from a raw data with lack of knowledge on its true shape. This paper proposes a data-driven modeling approach to reconstruct 3D rooftop models at city-scale from airborne laser scanning (ALS data. The focus of the proposed method is to implicitly derive the shape regularity of 3D building rooftops from given noisy information of building boundary in a progressive manner. This study covers a full chain of 3D building modeling from low level processing to realistic 3D building rooftop modeling. In the element clustering step, building-labeled point clouds are clustered into homogeneous groups by applying height similarity and plane similarity. Based on segmented clusters, linear modeling cues including outer boundaries, intersection lines, and step lines are extracted. Topology elements among the modeling cues are recovered by the Binary Space Partitioning (BSP technique. The regularity of the building rooftop model is achieved by an implicit regularization process in the framework of Minimum Description Length (MDL combined with Hypothesize and Test (HAT. The parameters governing the MDL optimization are automatically estimated based on Min-Max optimization and Entropy-based weighting method. The performance of the proposed method is tested over the International

Implicit Regularization for Reconstructing 3D Building Rooftop Models Using Airborne LiDAR Data.

Science.gov (United States)

Jung, Jaewook; Jwa, Yoonseok; Sohn, Gunho

2017-03-19

With rapid urbanization, highly accurate and semantically rich virtualization of building assets in 3D become more critical for supporting various applications, including urban planning, emergency response and location-based services. Many research efforts have been conducted to automatically reconstruct building models at city-scale from remotely sensed data. However, developing a fully-automated photogrammetric computer vision system enabling the massive generation of highly accurate building models still remains a challenging task. One the most challenging task for 3D building model reconstruction is to regularize the noises introduced in the boundary of building object retrieved from a raw data with lack of knowledge on its true shape. This paper proposes a data-driven modeling approach to reconstruct 3D rooftop models at city-scale from airborne laser scanning (ALS) data. The focus of the proposed method is to implicitly derive the shape regularity of 3D building rooftops from given noisy information of building boundary in a progressive manner. This study covers a full chain of 3D building modeling from low level processing to realistic 3D building rooftop modeling. In the element clustering step, building-labeled point clouds are clustered into homogeneous groups by applying height similarity and plane similarity. Based on segmented clusters, linear modeling cues including outer boundaries, intersection lines, and step lines are extracted. Topology elements among the modeling cues are recovered by the Binary Space Partitioning (BSP) technique. The regularity of the building rooftop model is achieved by an implicit regularization process in the framework of Minimum Description Length (MDL) combined with Hypothesize and Test (HAT). The parameters governing the MDL optimization are automatically estimated based on Min-Max optimization and Entropy-based weighting method. The performance of the proposed method is tested over the International Society for

Implicit learning of non-linguistic and linguistic regularities in children with dyslexia.

Science.gov (United States)

Nigro, Luciana; Jiménez-Fernández, Gracia; Simpson, Ian C; Defior, Sylvia

2016-07-01

One of the hallmarks of dyslexia is the failure to automatise written patterns despite repeated exposure to print. Although many explanations have been proposed to explain this problem, researchers have recently begun to explore the possibility that an underlying implicit learning deficit may play a role in dyslexia. This hypothesis has been investigated through non-linguistic tasks exploring implicit learning in a general domain. In this study, we examined the abilities of children with dyslexia to implicitly acquire positional regularities embedded in both non-linguistic and linguistic stimuli. In experiment 1, 42 children (21 with dyslexia and 21 typically developing) were exposed to rule-governed shape sequences; whereas in experiment 2, a new group of 42 children were exposed to rule-governed letter strings. Implicit learning was assessed in both experiments via a forced-choice task. Experiments 1 and 2 showed a similar pattern of results. ANOVA analyses revealed no significant differences between the dyslexic and the typically developing group, indicating that children with dyslexia are not impaired in the acquisition of simple positional regularities, regardless of the nature of the stimuli. However, within group t-tests suggested that children from the dyslexic group could not transfer the underlying positional rules to novel instances as efficiently as typically developing children.

Feature selection and multi-kernel learning for adaptive graph regularized nonnegative matrix factorization

KAUST Repository

Wang, Jim Jing-Yan

2014-09-20

Nonnegative matrix factorization (NMF), a popular part-based representation technique, does not capture the intrinsic local geometric structure of the data space. Graph regularized NMF (GNMF) was recently proposed to avoid this limitation by regularizing NMF with a nearest neighbor graph constructed from the input data set. However, GNMF has two main bottlenecks. First, using the original feature space directly to construct the graph is not necessarily optimal because of the noisy and irrelevant features and nonlinear distributions of data samples. Second, one possible way to handle the nonlinear distribution of data samples is by kernel embedding. However, it is often difficult to choose the most suitable kernel. To solve these bottlenecks, we propose two novel graph-regularized NMF methods, AGNMFFS and AGNMFMK, by introducing feature selection and multiple-kernel learning to the graph regularized NMF, respectively. Instead of using a fixed graph as in GNMF, the two proposed methods learn the nearest neighbor graph that is adaptive to the selected features and learned multiple kernels, respectively. For each method, we propose a unified objective function to conduct feature selection/multi-kernel learning, NMF and adaptive graph regularization simultaneously. We further develop two iterative algorithms to solve the two optimization problems. Experimental results on two challenging pattern classification tasks demonstrate that the proposed methods significantly outperform state-of-the-art data representation methods.

Influence of regular proprioceptive and bioenergetic physical activities on balance control in elderly women.

Science.gov (United States)

Gauchard, Gérome C; Gangloff, Pierre; Jeandel, Claude; Perrin, Philippe P

2003-09-01

Balance disorders increase considerably with age due to a decrease in posture regulation quality, and are accompanied by a higher risk of falling. Conversely, physical activities have been shown to improve the quality of postural control in elderly individuals and decrease the number of falls. The aim of this study was to evaluate the impact of two types of exercise on the visual afferent and on the different parameters of static balance regulation. Static postural control was evaluated in 44 healthy women aged over 60 years. Among them, 15 regularly practiced proprioceptive physical activities (Group I), 12 regularly practiced bioenergetic physical activities (Group II), and 18 controls walked on a regular basis (Group III). Group I participants displayed lower sway path and area values, whereas Group III participants displayed the highest, both in eyes-open and eyes-closed conditions. Group II participants displayed intermediate values, close to those of Group I in the eyes-open condition and those of Group III in the eyes-closed condition. Visual afferent contribution was more pronounced for Group II and III participants than for Group I participants. Proprioceptive exercise appears to have the best impact on balance regulation and precision. Besides, even if bioenergetic activity improves postural control in simple postural tasks, more difficult postural tasks show that this type of activity does not develop a neurosensorial proprioceptive input threshold as well, probably on account of the higher contribution of visual afferent.

Naming a Lego world. The role of language in the acquisition of abstract concepts.

Science.gov (United States)

Granito, Carmen; Scorolli, Claudia; Borghi, Anna Maria

2015-01-01

While embodied approaches of cognition have proved to be successful in explaining concrete concepts and words, they have more difficulties in accounting for abstract concepts and words, and several proposals have been put forward. This work aims to test the Words As Tools proposal, according to which both abstract and concrete concepts are grounded in perception, action and emotional systems, but linguistic information is more important for abstract than for concrete concept representation, due to the different ways they are acquired: while for the acquisition of the latter linguistic information might play a role, for the acquisition of the former it is instead crucial. We investigated the acquisition of concrete and abstract concepts and words, and verified its impact on conceptual representation. In Experiment 1, participants explored and categorized novel concrete and abstract entities, and were taught a novel label for each category. Later they performed a categorical recognition task and an image-word matching task to verify a) whether and how the introduction of language changed the previously formed categories, b) whether language had a major weight for abstract than for concrete words representation, and c) whether this difference had consequences on bodily responses. The results confirm that, even though both concrete and abstract concepts are grounded, language facilitates the acquisition of the latter and plays a major role in their representation, resulting in faster responses with the mouth, typically associated with language production. Experiment 2 was a rating test aiming to verify whether the findings of Experiment 1 were simply due to heterogeneity, i.e. to the fact that the members of abstract categories were more heterogeneous than those of concrete categories. The results confirmed the effectiveness of our operationalization, showing that abstract concepts are more associated with the mouth and concrete ones with the hand, independently from

Naming a Lego world. The role of language in the acquisition of abstract concepts.

Directory of Open Access Journals (Sweden)

Carmen Granito

Full Text Available While embodied approaches of cognition have proved to be successful in explaining concrete concepts and words, they have more difficulties in accounting for abstract concepts and words, and several proposals have been put forward. This work aims to test the Words As Tools proposal, according to which both abstract and concrete concepts are grounded in perception, action and emotional systems, but linguistic information is more important for abstract than for concrete concept representation, due to the different ways they are acquired: while for the acquisition of the latter linguistic information might play a role, for the acquisition of the former it is instead crucial. We investigated the acquisition of concrete and abstract concepts and words, and verified its impact on conceptual representation. In Experiment 1, participants explored and categorized novel concrete and abstract entities, and were taught a novel label for each category. Later they performed a categorical recognition task and an image-word matching task to verify a whether and how the introduction of language changed the previously formed categories, b whether language had a major weight for abstract than for concrete words representation, and c whether this difference had consequences on bodily responses. The results confirm that, even though both concrete and abstract concepts are grounded, language facilitates the acquisition of the latter and plays a major role in their representation, resulting in faster responses with the mouth, typically associated with language production. Experiment 2 was a rating test aiming to verify whether the findings of Experiment 1 were simply due to heterogeneity, i.e. to the fact that the members of abstract categories were more heterogeneous than those of concrete categories. The results confirmed the effectiveness of our operationalization, showing that abstract concepts are more associated with the mouth and concrete ones with the hand

Developing communicative competence through thinking tasks

DEFF Research Database (Denmark)

Maslo, Elina

Developing communicative competence through thinking tasks - Experimenting with Thinking Approach in Danish as Second Language ClassroomSession on Innovations in the classroom, a presentation. Abstract for the conference Creativity & Thinking Skills in Learning, teaching & Management. Riga 19......-20 September 2014 Elina Maslo, Aarhus University, Department of Education, elma@edu.au.dk Summary: The goal of this presentation is to present some of the experiences with thinking tasks in the Danish language classroom, conducted in the Nordplus Nordic Language Project “Problem solving tasks for learning...... of Danish as second and foreign language in transformative learning spaces”. Two teachers have developed and tried out some thinking tasks in their classrooms, with the aim to foster the development of students´ communicative competence. The learning processes from two classrooms will be analysed...

The geometry of continuum regularization

International Nuclear Information System (INIS)

Halpern, M.B.

1987-03-01

This lecture is primarily an introduction to coordinate-invariant regularization, a recent advance in the continuum regularization program. In this context, the program is seen as fundamentally geometric, with all regularization contained in regularized DeWitt superstructures on field deformations

Regular expression containment

DEFF Research Database (Denmark)

Henglein, Fritz; Nielsen, Lasse

2011-01-01

We present a new sound and complete axiomatization of regular expression containment. It consists of the conventional axiomatiza- tion of concatenation, alternation, empty set and (the singleton set containing) the empty string as an idempotent semiring, the fixed- point rule E* = 1 + E × E......* for Kleene-star, and a general coin- duction rule as the only additional rule. Our axiomatization gives rise to a natural computational inter- pretation of regular expressions as simple types that represent parse trees, and of containment proofs as coercions. This gives the axiom- atization a Curry......-Howard-style constructive interpretation: Con- tainment proofs do not only certify a language-theoretic contain- ment, but, under our computational interpretation, constructively transform a membership proof of a string in one regular expres- sion into a membership proof of the same string in another regular expression. We...

Supersymmetric dimensional regularization

International Nuclear Information System (INIS)

Siegel, W.; Townsend, P.K.; van Nieuwenhuizen, P.

1980-01-01

There is a simple modification of dimension regularization which preserves supersymmetry: dimensional reduction to real D < 4, followed by analytic continuation to complex D. In terms of component fields, this means fixing the ranges of all indices on the fields (and therefore the numbers of Fermi and Bose components). For superfields, it means continuing in the dimensionality of x-space while fixing the dimensionality of theta-space. This regularization procedure allows the simple manipulation of spinor derivatives in supergraph calculations. The resulting rules are: (1) First do all algebra exactly as in D = 4; (2) Then do the momentum integrals as in ordinary dimensional regularization. This regularization procedure needs extra rules before one can say that it is consistent. Such extra rules needed for superconformal anomalies are discussed. Problems associated with renormalizability and higher order loops are also discussed

Robust visual tracking via structured multi-task sparse learning

KAUST Repository

Zhang, Tianzhu

2012-11-09

In this paper, we formulate object tracking in a particle filter framework as a structured multi-task sparse learning problem, which we denote as Structured Multi-Task Tracking (S-MTT). Since we model particles as linear combinations of dictionary templates that are updated dynamically, learning the representation of each particle is considered a single task in Multi-Task Tracking (MTT). By employing popular sparsity-inducing lp,q mixed norms (specifically p∈2,∞ and q=1), we regularize the representation problem to enforce joint sparsity and learn the particle representations together. As compared to previous methods that handle particles independently, our results demonstrate that mining the interdependencies between particles improves tracking performance and overall computational complexity. Interestingly, we show that the popular L1 tracker (Mei and Ling, IEEE Trans Pattern Anal Mach Intel 33(11):2259-2272, 2011) is a special case of our MTT formulation (denoted as the L11 tracker) when p=q=1. Under the MTT framework, some of the tasks (particle representations) are often more closely related and more likely to share common relevant covariates than other tasks. Therefore, we extend the MTT framework to take into account pairwise structural correlations between particles (e.g. spatial smoothness of representation) and denote the novel framework as S-MTT. The problem of learning the regularized sparse representation in MTT and S-MTT can be solved efficiently using an Accelerated Proximal Gradient (APG) method that yields a sequence of closed form updates. As such, S-MTT and MTT are computationally attractive. We test our proposed approach on challenging sequences involving heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that S-MTT is much better than MTT, and both methods consistently outperform state-of-the-art trackers. © 2012 Springer Science+Business Media New York.

The Neural Mechanisms Underlying Internally and Externally Guided Task Selection

Science.gov (United States)

Orr, Joseph M.; Banich, Marie T.

2013-01-01

While some prior work suggests that medial prefrontal cortex (MFC) regions mediate freely chosen actions, other work suggests that the lateral frontal pole (LFP) is responsible for control of abstract, internal goals. The present study uses fMRI to determine whether the voluntary selection of a task in pursuit of an overall goal relies on MFC regions or the LFP. To do so, we used a modified voluntary task switching (VTS) paradigm, in which participants choose an individual task to perform on each trial (i.e., a subgoal), under instructions to perform the tasks equally often and in a random order (i.e. the overall goal). In conjunction, we examined patterns of activation in the face of irrelevant, but task-related external stimuli that might nonetheless influence task selection. While there was some evidence that the MFC was involved in voluntary task selection, we found that the LFP and anterior insula (AI) were crucial to task selection in the pursuit of an overall goal. In addition, activation of the LFP and AI increased in the face of environmental stimuli that might serve as an interfering or conflicting external bias on voluntary task choice. These findings suggest that the LFP supports task selection according to abstract, internal goals, and leaves open the possibility that MFC may guide action selection in situations lacking in such top-down biases. As such, the current study represents a critical step towards understanding the neural underpinnings of how tasks are selected voluntarily to enable an overarching goal. PMID:23994316

Early positivity signals changes in an abstract linguistic pattern.

Directory of Open Access Journals (Sweden)

Júlia Monte-Ordoño

Full Text Available The extraction of abstract structures from speech (or from gestures in the case of sign languages has been claimed to be a fundamental mechanism for language acquisition. In the present study we registered the neural responses that are triggered when a violation of an abstract, token-independent rule is detected. We registered ERPs while presenting participants with trisyllabic CVCVCV nonsense words in an oddball paradigm. Standard stimuli followed an ABB rule (where A and B are different syllables. Importantly, to distinguish neural responses triggered by changes in surface information from responses triggered by changes in the underlying abstract structure, we used two types of deviant stimuli. Phoneme deviants differed from standards only in their phonemes. Rule deviants differed from standards in both their phonemes and their composing rule. We observed a significant positivity as early as 300 ms after the presentation of deviant stimuli that violated the abstract rule (Rule deviants. The amplitude of this neural response was correlated with participants' performance in a behavioral rule learning test. Differences in electrophysiological responses observed between learners and non-learners suggest that individual differences in an abstract rule learning task might be related to how listeners select relevant sources of information.

Regular use of aspirin and pancreatic cancer risk

Directory of Open Access Journals (Sweden)

Mahoney Martin C

2002-09-01

Full Text Available Abstract Background Regular use of aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs has been consistently associated with reduced risk of colorectal cancer and adenoma, and there is some evidence for a protective effect for other types of cancer. As experimental studies reveal a possible role for NSAIDs is reducing the risk of pancreatic cancer, epidemiological studies examining similar associations in human populations become more important. Methods In this hospital-based case-control study, 194 patients with pancreatic cancer were compared to 582 age and sex-matched patients with non-neoplastic conditions to examine the association between aspirin use and risk of pancreatic cancer. All participants received medical services at the Roswell Park Cancer Institute in Buffalo, NY and completed a comprehensive epidemiologic questionnaire that included information on demographics, lifestyle factors and medical history as well as frequency and duration of aspirin use. Patients using at least one tablet per week for at least six months were classified as regular aspirin users. Unconditional logistic regression was used to compute crude and adjusted odds ratios (ORs with 95% confidence intervals (CIs. Results Pancreatic cancer risk in aspirin users was not changed relative to non-users (adjusted OR = 1.00; 95% CI 0.72–1.39. No significant change in risk was found in relation to greater frequency or prolonged duration of use, in the total sample or in either gender. Conclusions These data suggest that regular aspirin use may not be associated with lower risk of pancreatic cancer.

Regularization by External Variables

DEFF Research Database (Denmark)

Bossolini, Elena; Edwards, R.; Glendinning, P. A.

2016-01-01

Regularization was a big topic at the 2016 CRM Intensive Research Program on Advances in Nonsmooth Dynamics. There are many open questions concerning well known kinds of regularization (e.g., by smoothing or hysteresis). Here, we propose a framework for an alternative and important kind of regula......Regularization was a big topic at the 2016 CRM Intensive Research Program on Advances in Nonsmooth Dynamics. There are many open questions concerning well known kinds of regularization (e.g., by smoothing or hysteresis). Here, we propose a framework for an alternative and important kind...

Regular Single Valued Neutrosophic Hypergraphs

Directory of Open Access Journals (Sweden)

Muhammad Aslam Malik

2016-12-01

Full Text Available In this paper, we define the regular and totally regular single valued neutrosophic hypergraphs, and discuss the order and size along with properties of regular and totally regular single valued neutrosophic hypergraphs. We also extend work on completeness of single valued neutrosophic hypergraphs.

Brain network response underlying decisions about abstract reinforcers.

Science.gov (United States)

Mills-Finnerty, Colleen; Hanson, Catherine; Hanson, Stephen Jose

2014-12-01

Decision making studies typically use tasks that involve concrete action-outcome contingencies, in which subjects do something and get something. No studies have addressed decision making involving abstract reinforcers, where there are no action-outcome contingencies and choices are entirely hypothetical. The present study examines these kinds of choices, as well as whether the same biases that exist for concrete reinforcer decisions, specifically framing effects, also apply during abstract reinforcer decisions. We use both General Linear Model as well as Bayes network connectivity analysis using the Independent Multi-sample Greedy Equivalence Search (IMaGES) algorithm to examine network response underlying choices for abstract reinforcers under positive and negative framing. We find for the first time that abstract reinforcer decisions activate the same network of brain regions as concrete reinforcer decisions, including the striatum, insula, anterior cingulate, and VMPFC, results that are further supported via comparison to a meta-analysis of decision making studies. Positive and negative framing activated different parts of this network, with stronger activation in VMPFC during negative framing and in DLPFC during positive, suggesting different decision making pathways depending on frame. These results were further clarified using connectivity analysis, which revealed stronger connections between anterior cingulate, insula, and accumbens during negative framing compared to positive. Taken together, these results suggest that not only do abstract reinforcer decisions rely on the same brain substrates as concrete reinforcers, but that the response underlying framing effects on abstract reinforcers also resemble those for concrete reinforcers, specifically increased limbic system connectivity during negative frames. Copyright © 2014 Elsevier Inc. All rights reserved.

Neural Correlates of Task Cost for Stance Control with an Additional Motor Task: Phase-Locked Electroencephalogram Responses

Science.gov (United States)

Hwang, Ing-Shiou; Huang, Cheng-Ya

2016-01-01

With appropriate reallocation of central resources, the ability to maintain an erect posture is not necessarily degraded by a concurrent motor task. This study investigated the neural control of a particular postural-suprapostural procedure involving brain mechanisms to solve crosstalk between posture and motor subtasks. Participants completed a single posture task and a dual-task while concurrently conducting force-matching and maintaining a tilted stabilometer stance at a target angle. Stabilometer movements and event-related potentials (ERPs) were recorded. The added force-matching task increased the irregularity of postural response rather than the size of postural response prior to force-matching. In addition, the added force-matching task during stabilometer stance led to marked topographic ERP modulation, with greater P2 positivity in the frontal and sensorimotor-parietal areas of the N1-P2 transitional phase and in the sensorimotor-parietal area of the late P2 phase. The time-frequency distribution of the ERP primary principal component revealed that the dual-task condition manifested more pronounced delta (1–4 Hz) and beta (13–35 Hz) synchronizations but suppressed theta activity (4–8 Hz) before force-matching. The dual-task condition also manifested coherent fronto-parietal delta activity in the P2 period. In addition to a decrease in postural regularity, this study reveals spatio-temporal and temporal-spectral reorganizations of ERPs in the fronto-sensorimotor-parietal network due to the added suprapostural motor task. For a particular set of postural-suprapostural task, the behavior and neural data suggest a facilitatory role of autonomous postural response and central resource expansion with increasing interregional interactions for task-shift and planning the motor-suprapostural task. PMID:27010634

The generative power of weighted one-sided and regular sticker systems

Science.gov (United States)

Siang, Gan Yee; Heng, Fong Wan; Sarmin, Nor Haniza; Turaev, Sherzod

2014-06-01

Sticker systems were introduced in 1998 as one of the DNA computing models by using the recombination behavior of DNA molecules. The Watson-Crick complementary principle of DNA molecules is abstractly used in the sticker systems to perform the computation of sticker systems. In this paper, the generative power of weighted one-sided sticker systems and weighted regular sticker systems are investigated. Moreover, the relationship of the families of languages generated by these two variants of sticker systems to the Chomsky hierarchy is also presented.

Enrichment Effects of Gestures and Pictures on Abstract Words in a Second Language.

Science.gov (United States)

Repetto, Claudia; Pedroli, Elisa; Macedonia, Manuela

2017-01-01

Laboratory research has demonstrated that multisensory enrichment promotes verbal learning in a foreign language (L2). Enrichment can be done in various ways, e.g., by adding a picture that illustrates the L2 word's meaning or by the learner performing a gesture to the word (enactment). Most studies have tested enrichment on concrete but not on abstract words. Unlike concrete words, the representation of abstract words is deprived of sensory-motor features. This has been addressed as one of the reasons why abstract words are difficult to remember. Here, we ask whether a brief enrichment training by means of pictures and by self-performed gestures also enhances the memorability of abstract words in L2. Further, we explore which of these two enrichment strategies is more effective. Twenty young adults learned 30 novel abstract words in L2 according to three encoding conditions: (1) reading, (2) reading and pairing the novel word to a picture, and (3) reading and enacting the word by means of a gesture. We measured memory performance in free and cued recall tests, as well as in a visual recognition task. Words encoded with gestures were better remembered in the free recall in the native language (L1). When recognizing the novel words, participants made less errors for words encoded with gestures compared to words encoded with pictures. The reaction times in the recognition task did not differ across conditions. The present findings support, even if only partially, the idea that enactment promotes learning of abstract words and that it is superior to enrichment by means of pictures even after short training.

Enrichment Effects of Gestures and Pictures on Abstract Words in a Second Language

Directory of Open Access Journals (Sweden)

Claudia Repetto

2017-12-01

Full Text Available Laboratory research has demonstrated that multisensory enrichment promotes verbal learning in a foreign language (L2. Enrichment can be done in various ways, e.g., by adding a picture that illustrates the L2 word’s meaning or by the learner performing a gesture to the word (enactment. Most studies have tested enrichment on concrete but not on abstract words. Unlike concrete words, the representation of abstract words is deprived of sensory-motor features. This has been addressed as one of the reasons why abstract words are difficult to remember. Here, we ask whether a brief enrichment training by means of pictures and by self-performed gestures also enhances the memorability of abstract words in L2. Further, we explore which of these two enrichment strategies is more effective. Twenty young adults learned 30 novel abstract words in L2 according to three encoding conditions: (1 reading, (2 reading and pairing the novel word to a picture, and (3 reading and enacting the word by means of a gesture. We measured memory performance in free and cued recall tests, as well as in a visual recognition task. Words encoded with gestures were better remembered in the free recall in the native language (L1. When recognizing the novel words, participants made less errors for words encoded with gestures compared to words encoded with pictures. The reaction times in the recognition task did not differ across conditions. The present findings support, even if only partially, the idea that enactment promotes learning of abstract words and that it is superior to enrichment by means of pictures even after short training.

On a correspondence between regular and non-regular operator monotone functions

DEFF Research Database (Denmark)

Gibilisco, P.; Hansen, Frank; Isola, T.

2009-01-01

We prove the existence of a bijection between the regular and the non-regular operator monotone functions satisfying a certain functional equation. As an application we give a new proof of the operator monotonicity of certain functions related to the Wigner-Yanase-Dyson skew information....

Noninvasive technique for measurement of heartbeat regularity in zebrafish (Danio rerio embryos

Directory of Open Access Journals (Sweden)

Cheng Shuk

2009-02-01

Full Text Available Abstract Background Zebrafish (Danio rerio, due to its optical accessibility and similarity to human, has emerged as model organism for cardiac research. Although various methods have been developed to assess cardiac functions in zebrafish embryos, there lacks a method to assess heartbeat regularity in blood vessels. Heartbeat regularity is an important parameter for cardiac function and is associated with cardiotoxicity in human being. Using stereomicroscope and digital video camera, we have developed a simple, noninvasive method to measure the heart rate and heartbeat regularity in peripheral blood vessels. Anesthetized embryos were mounted laterally in agarose on a slide and the caudal blood circulation of zebrafish embryo was video-recorded under stereomicroscope and the data was analyzed by custom-made software. The heart rate was determined by digital motion analysis and power spectral analysis through extraction of frequency characteristics of the cardiac rhythm. The heartbeat regularity, defined as the rhythmicity index, was determined by short-time Fourier Transform analysis. Results The heart rate measured by this noninvasive method in zebrafish embryos at 52 hour post-fertilization was similar to that determined by direct visual counting of ventricle beating (p > 0.05. In addition, the method was validated by a known cardiotoxic drug, terfenadine, which affects heartbeat regularity in humans and induces bradycardia and atrioventricular blockage in zebrafish. A significant decrease in heart rate was found by our method in treated embryos (p p Conclusion The data support and validate this rapid, simple, noninvasive method, which includes video image analysis and frequency analysis. This method is capable of measuring the heart rate and heartbeat regularity simultaneously via the analysis of caudal blood flow in zebrafish embryos. With the advantages of rapid sample preparation procedures, automatic image analysis and data analysis, this

Structure-Based Low-Rank Model With Graph Nuclear Norm Regularization for Noise Removal.

Science.gov (United States)

Ge, Qi; Jing, Xiao-Yuan; Wu, Fei; Wei, Zhi-Hui; Xiao, Liang; Shao, Wen-Ze; Yue, Dong; Li, Hai-Bo

2017-07-01

Nonlocal image representation methods, including group-based sparse coding and block-matching 3-D filtering, have shown their great performance in application to low-level tasks. The nonlocal prior is extracted from each group consisting of patches with similar intensities. Grouping patches based on intensity similarity, however, gives rise to disturbance and inaccuracy in estimation of the true images. To address this problem, we propose a structure-based low-rank model with graph nuclear norm regularization. We exploit the local manifold structure inside a patch and group the patches by the distance metric of manifold structure. With the manifold structure information, a graph nuclear norm regularization is established and incorporated into a low-rank approximation model. We then prove that the graph-based regularization is equivalent to a weighted nuclear norm and the proposed model can be solved by a weighted singular-value thresholding algorithm. Extensive experiments on additive white Gaussian noise removal and mixed noise removal demonstrate that the proposed method achieves a better performance than several state-of-the-art algorithms.

Convergence and fluctuations of Regularized Tyler estimators

KAUST Repository

Kammoun, Abla

2015-10-26

This article studies the behavior of regularized Tyler estimators (RTEs) of scatter matrices. The key advantages of these estimators are twofold. First, they guarantee by construction a good conditioning of the estimate and second, being a derivative of robust Tyler estimators, they inherit their robustness properties, notably their resilience to the presence of outliers. Nevertheless, one major problem that poses the use of RTEs in practice is represented by the question of setting the regularization parameter p. While a high value of p is likely to push all the eigenvalues away from zero, it comes at the cost of a larger bias with respect to the population covariance matrix. A deep understanding of the statistics of RTEs is essential to come up with appropriate choices for the regularization parameter. This is not an easy task and might be out of reach, unless one considers asymptotic regimes wherein the number of observations n and/or their size N increase together. First asymptotic results have recently been obtained under the assumption that N and n are large and commensurable. Interestingly, no results concerning the regime of n going to infinity with N fixed exist, even though the investigation of this assumption has usually predated the analysis of the most difficult N and n large case. This motivates our work. In particular, we prove in the present paper that the RTEs converge to a deterministic matrix when n → ∞ with N fixed, which is expressed as a function of the theoretical covariance matrix. We also derive the fluctuations of the RTEs around this deterministic matrix and establish that these fluctuations converge in distribution to a multivariate Gaussian distribution with zero mean and a covariance depending on the population covariance and the parameter.

Convergence and fluctuations of Regularized Tyler estimators

KAUST Repository

Kammoun, Abla; Couillet, Romain; Pascal, Frederic; Alouini, Mohamed-Slim

2015-01-01

This article studies the behavior of regularized Tyler estimators (RTEs) of scatter matrices. The key advantages of these estimators are twofold. First, they guarantee by construction a good conditioning of the estimate and second, being a derivative of robust Tyler estimators, they inherit their robustness properties, notably their resilience to the presence of outliers. Nevertheless, one major problem that poses the use of RTEs in practice is represented by the question of setting the regularization parameter p. While a high value of p is likely to push all the eigenvalues away from zero, it comes at the cost of a larger bias with respect to the population covariance matrix. A deep understanding of the statistics of RTEs is essential to come up with appropriate choices for the regularization parameter. This is not an easy task and might be out of reach, unless one considers asymptotic regimes wherein the number of observations n and/or their size N increase together. First asymptotic results have recently been obtained under the assumption that N and n are large and commensurable. Interestingly, no results concerning the regime of n going to infinity with N fixed exist, even though the investigation of this assumption has usually predated the analysis of the most difficult N and n large case. This motivates our work. In particular, we prove in the present paper that the RTEs converge to a deterministic matrix when n → ∞ with N fixed, which is expressed as a function of the theoretical covariance matrix. We also derive the fluctuations of the RTEs around this deterministic matrix and establish that these fluctuations converge in distribution to a multivariate Gaussian distribution with zero mean and a covariance depending on the population covariance and the parameter.

Abstract Level Parallelization of Finite Difference Methods

Directory of Open Access Journals (Sweden)

Edwin Vollebregt

1997-01-01

Full Text Available A formalism is proposed for describing finite difference calculations in an abstract way. The formalism consists of index sets and stencils, for characterizing the structure of sets of data items and interactions between data items (“neighbouring relations”. The formalism provides a means for lifting programming to a more abstract level. This simplifies the tasks of performance analysis and verification of correctness, and opens the way for automaticcode generation. The notation is particularly useful in parallelization, for the systematic construction of parallel programs in a process/channel programming paradigm (e.g., message passing. This is important because message passing, unfortunately, still is the only approach that leads to acceptable performance for many more unstructured or irregular problems on parallel computers that have non-uniform memory access times. It will be shown that the use of index sets and stencils greatly simplifies the determination of which data must be exchanged between different computing processes.

Pyrcca: regularized kernel canonical correlation analysis in Python and its applications to neuroimaging

OpenAIRE

Natalia Y Bilenko; Jack L Gallant; Jack L Gallant

2016-01-01

In this article we introduce Pyrcca, an open-source Python package for performing canonical correlation analysis (CCA). CCA is a multivariate analysis method for identifying relationships between sets of variables. Pyrcca supports CCA with or without regularization, and with or without linear, polynomial, or Gaussian kernelization. We first use an abstract example to describe Pyrcca functionality. We then demonstrate how Pyrcca can be used to analyze neuroimaging data. Specifically, we use Py...

Abstract quantum computing machines and quantum computational logics

Science.gov (United States)

Chiara, Maria Luisa Dalla; Giuntini, Roberto; Sergioli, Giuseppe; Leporini, Roberto

2016-06-01

Classical and quantum parallelism are deeply different, although it is sometimes claimed that quantum Turing machines are nothing but special examples of classical probabilistic machines. We introduce the concepts of deterministic state machine, classical probabilistic state machine and quantum state machine. On this basis, we discuss the question: To what extent can quantum state machines be simulated by classical probabilistic state machines? Each state machine is devoted to a single task determined by its program. Real computers, however, behave differently, being able to solve different kinds of problems. This capacity can be modeled, in the quantum case, by the mathematical notion of abstract quantum computing machine, whose different programs determine different quantum state machines. The computations of abstract quantum computing machines can be linguistically described by the formulas of a particular form of quantum logic, termed quantum computational logic.

Stochastic analytic regularization

International Nuclear Information System (INIS)

Alfaro, J.

1984-07-01

Stochastic regularization is reexamined, pointing out a restriction on its use due to a new type of divergence which is not present in the unregulated theory. Furthermore, we introduce a new form of stochastic regularization which permits the use of a minimal subtraction scheme to define the renormalized Green functions. (author)

Abstract Representations of Object-Directed Action in the Left Inferior Parietal Lobule.

Science.gov (United States)

Chen, Quanjing; Garcea, Frank E; Jacobs, Robert A; Mahon, Bradford Z

2018-06-01

Prior neuroimaging and neuropsychological research indicates that the left inferior parietal lobule in the human brain is a critical substrate for representing object manipulation knowledge. In the present functional MRI study we used multivoxel pattern analyses to test whether action similarity among objects can be decoded in the inferior parietal lobule independent of the task applied to objects (identification or pantomime) and stimulus format in which stimuli are presented (pictures or printed words). Participants pantomimed the use of objects, cued by printed words, or identified pictures of objects. Classifiers were trained and tested across task (e.g., training data: pantomime; testing data: identification), stimulus format (e.g., training data: word format; testing format: picture) and specific objects (e.g., training data: scissors vs. corkscrew; testing data: pliers vs. screwdriver). The only brain region in which action relations among objects could be decoded across task, stimulus format and objects was the inferior parietal lobule. By contrast, medial aspects of the ventral surface of the left temporal lobe represented object function, albeit not at the same level of abstractness as actions in the inferior parietal lobule. These results suggest compulsory access to abstract action information in the inferior parietal lobe even when simply identifying objects.

Control processes through the suppression of the automatic response activation triggered by task-irrelevant information in the Simon-type tasks.

Science.gov (United States)

Kim, Sanga; Lee, Sang Ho; Cho, Yang Seok

2015-11-01

The congruency sequence effect, one of the indices of cognitive control, refers to a smaller congruency effect after an incongruent than congruent trial. Although the effect has been found across a variety of conflict tasks, there is not yet agreement on the underlying mechanism. The present study investigated the mechanism underlying cognitive control by using a cross-task paradigm. In Experiments 1, 2, and 3, participants performed a modified Simon task and a spatial Stroop task alternately in a trial-by-trial manner. The task-irrelevant dimension of the two tasks was perceptually and conceptually identical in Experiment 1, whereas it was perceptually different but conceptually identical in Experiment 2. The response sets for both tasks were different in Experiment 3. In Experiment 4, participants performed two Simon tasks with different task-relevant dimensions. In all experiments in which the task-irrelevant dimension and response mode were shared, significant congruency sequence effects were found between the two different congruencies, indicating that Simon-type conflicts were resolved by a control mechanism, which is specific to an abstract task-irrelevant stimulus spatial dimension. Copyright © 2015 Elsevier B.V. All rights reserved.

The impact of the inclusion of students with handicaps and disabilities in the regular education science classroom

Science.gov (United States)

Donald, Cathey Nolan

This study was conducted to determine the impact of the inclusion of students with handicaps and disabilities in the regular education science classroom. Surveys were mailed to the members of the Alabama Science Teachers Association to obtain information from teachers in inclusive classrooms. Survey responses from teachers provide insight into these classrooms. This study reports the results of the teachers surveyed. Results indicate multiple changes occur in the educational opportunities presented to regular education students when students with handicaps and disabilities are included in the regular science classroom. Responding teachers (60%) report omitting activities that formerly provided experiences for students, such as laboratory activities using dangerous materials, field activities, and some group activities. Also omitted, in many instances (64.1%), are skill building opportunities of word problems and higher order thinking skills. Regular education students participate in classes where discipline problems related to included students are reported as the teachers most time consuming task. In these classrooms, directions are repeated frequently, reteaching of material already taught occurs, and the pace of instruction has been slowed. These changes to the regular classroom occur across school levels. Many teachers (44.9%) report they do not see benefits associated with the inclusion of students with special needs in the regular classroom.

Spatial Programming for Industrial Robots Through Task Demonstration

OpenAIRE

Jens Lambrecht; Martin Kleinsorge; Martin Rosenstrauch; Jörg Krüger

2013-01-01

Abstract We present an intuitive system for the programming of industrial robots using markerless gesture recognition and mobile augmented reality in terms of programming by demonstration. The approach covers gesture-based task definition and adaption by human demonstration, as well as task evaluation through augmented reality. A 3D motion tracking system and a handheld device establish the basis for the presented spatial programming system. In this publication, we present a prototype toward ...

Learning and transfer of category knowledge in an indirect categorization task.

Science.gov (United States)

Helie, Sebastien; Ashby, F Gregory

2012-05-01

Knowledge representations acquired during category learning experiments are 'tuned' to the task goal. A useful paradigm to study category representations is indirect category learning. In the present article, we propose a new indirect categorization task called the "same"-"different" categorization task. The same-different categorization task is a regular same-different task, but the question asked to the participants is about the stimulus category membership instead of stimulus identity. Experiment 1 explores the possibility of indirectly learning rule-based and information-integration category structures using the new paradigm. The results suggest that there is little learning about the category structures resulting from an indirect categorization task unless the categories can be separated by a one-dimensional rule. Experiment 2 explores whether a category representation learned indirectly can be used in a direct classification task (and vice versa). The results suggest that previous categorical knowledge acquired during a direct classification task can be expressed in the same-different categorization task only when the categories can be separated by a rule that is easily verbalized. Implications of these results for categorization research are discussed.

Consistency of performance of robot-assisted surgical tasks in virtual reality.

Science.gov (United States)

Suh, I H; Siu, K-C; Mukherjee, M; Monk, E; Oleynikov, D; Stergiou, N

2009-01-01

The purpose of this study was to investigate consistency of performance of robot-assisted surgical tasks in a virtual reality environment. Eight subjects performed two surgical tasks, bimanual carrying and needle passing, with both the da Vinci surgical robot and a virtual reality equivalent environment. Nonlinear analysis was utilized to evaluate consistency of performance by calculating the regularity and the amount of divergence in the movement trajectories of the surgical instrument tips. Our results revealed that movement patterns for both training tasks were statistically similar between the two environments. Consistency of performance as measured by nonlinear analysis could be an appropriate methodology to evaluate the complexity of the training tasks between actual and virtual environments and assist in developing better surgical training programs.

Effective field theory dimensional regularization

International Nuclear Information System (INIS)

Lehmann, Dirk; Prezeau, Gary

2002-01-01

A Lorentz-covariant regularization scheme for effective field theories with an arbitrary number of propagating heavy and light particles is given. This regularization scheme leaves the low-energy analytic structure of Greens functions intact and preserves all the symmetries of the underlying Lagrangian. The power divergences of regularized loop integrals are controlled by the low-energy kinematic variables. Simple diagrammatic rules are derived for the regularization of arbitrary one-loop graphs and the generalization to higher loops is discussed

Effective field theory dimensional regularization

Science.gov (United States)

Lehmann, Dirk; Prézeau, Gary

2002-01-01

A Lorentz-covariant regularization scheme for effective field theories with an arbitrary number of propagating heavy and light particles is given. This regularization scheme leaves the low-energy analytic structure of Greens functions intact and preserves all the symmetries of the underlying Lagrangian. The power divergences of regularized loop integrals are controlled by the low-energy kinematic variables. Simple diagrammatic rules are derived for the regularization of arbitrary one-loop graphs and the generalization to higher loops is discussed.

Evidence for cross-script abstract identities in learners of Japanese kana.

Science.gov (United States)

Schubert, Teresa; Gawthrop, Roderick; Kinoshita, Sachiko

2018-05-07

The presence of abstract letter identity representations in the Roman alphabet has been well documented. These representations are invariant to letter case (upper vs. lower) and visual appearance. For example, "a" and "A" are represented by the same abstract identity. Recent research has begun to consider whether the processing of non-Roman orthographies also involves abstract orthographic representations. In the present study, we sought evidence for abstract identities in Japanese kana, which consist of two scripts, hiragana and katakana. Abstract identities would be invariant to the script used as well as to the degree of visual similarity. We adapted the cross-case masked-priming letter match task used in previous research on Roman letters, by presenting cross-script kana pairs and testing adult beginning -to- intermediate Japanese second-language (L2) learners (first-language English readers). We found robust cross-script priming effects, which were equal in magnitude for visually similar (e.g., り/リ) and dissimilar (e.g., あ/ア) kana pairs. This pattern was found despite participants' imperfect explicit knowledge of the kana names, particularly for katakana. We also replicated prior findings from Roman abstract letter identities in the same participants. Ours is the first study reporting abstract kana identity priming (in adult L2 learners). Furthermore, these representations were acquired relatively early in our adult L2 learners.

Abstract knowledge versus direct experience in processing of binomial expressions.

Science.gov (United States)

Morgan, Emily; Levy, Roger

2016-12-01

We ask whether word order preferences for binomial expressions of the form A and B (e.g. bread and butter) are driven by abstract linguistic knowledge of ordering constraints referencing the semantic, phonological, and lexical properties of the constituent words, or by prior direct experience with the specific items in questions. Using forced-choice and self-paced reading tasks, we demonstrate that online processing of never-before-seen binomials is influenced by abstract knowledge of ordering constraints, which we estimate with a probabilistic model. In contrast, online processing of highly frequent binomials is primarily driven by direct experience, which we estimate from corpus frequency counts. We propose a trade-off wherein processing of novel expressions relies upon abstract knowledge, while reliance upon direct experience increases with increased exposure to an expression. Our findings support theories of language processing in which both compositional generation and direct, holistic reuse of multi-word expressions play crucial roles. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

A unified software framework for deriving, visualizing, and exploring abstraction networks for ontologies

Science.gov (United States)

Ochs, Christopher; Geller, James; Perl, Yehoshua; Musen, Mark A.

2016-01-01

Software tools play a critical role in the development and maintenance of biomedical ontologies. One important task that is difficult without software tools is ontology quality assurance. In previous work, we have introduced different kinds of abstraction networks to provide a theoretical foundation for ontology quality assurance tools. Abstraction networks summarize the structure and content of ontologies. One kind of abstraction network that we have used repeatedly to support ontology quality assurance is the partial-area taxonomy. It summarizes structurally and semantically similar concepts within an ontology. However, the use of partial-area taxonomies was ad hoc and not generalizable. In this paper, we describe the Ontology Abstraction Framework (OAF), a unified framework and software system for deriving, visualizing, and exploring partial-area taxonomy abstraction networks. The OAF includes support for various ontology representations (e.g., OWL and SNOMED CT's relational format). A Protégé plugin for deriving “live partial-area taxonomies” is demonstrated. PMID:27345947

Learning SAS’s Perl Regular Expression Matching the Easy Way: By Doing

Science.gov (United States)

2015-01-12

Doing 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Paul Genovesi 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...regex_learning_tool allows both beginner and expert to efficiently practice PRX matching by selecting and processing only the match records that the user is interested...perl regular expression and/or source string. The regex_learning_tool allows both beginner and expert to efficiently practice PRX matching by

Hierarchical regular small-world networks

International Nuclear Information System (INIS)

Boettcher, Stefan; Goncalves, Bruno; Guclu, Hasan

2008-01-01

Two new networks are introduced that resemble small-world properties. These networks are recursively constructed but retain a fixed, regular degree. They possess a unique one-dimensional lattice backbone overlaid by a hierarchical sequence of long-distance links, mixing real-space and small-world features. Both networks, one 3-regular and the other 4-regular, lead to distinct behaviors, as revealed by renormalization group studies. The 3-regular network is planar, has a diameter growing as √N with system size N, and leads to super-diffusion with an exact, anomalous exponent d w = 1.306..., but possesses only a trivial fixed point T c = 0 for the Ising ferromagnet. In turn, the 4-regular network is non-planar, has a diameter growing as ∼2 √(log 2 N 2 ) , exhibits 'ballistic' diffusion (d w = 1), and a non-trivial ferromagnetic transition, T c > 0. It suggests that the 3-regular network is still quite 'geometric', while the 4-regular network qualifies as a true small world with mean-field properties. As an engineering application we discuss synchronization of processors on these networks. (fast track communication)

75 FR 76006 - Regular Meeting

Science.gov (United States)

2010-12-07

... FARM CREDIT SYSTEM INSURANCE CORPORATION Regular Meeting AGENCY: Farm Credit System Insurance Corporation Board. ACTION: Regular meeting. SUMMARY: Notice is hereby given of the regular meeting of the Farm Credit System Insurance Corporation Board (Board). Date and Time: The meeting of the Board will be held...

Extended abstracts Fall 2012 automorphisms of free groups

CERN Document Server

Lustig, Martin; Ventura, Enric

2014-01-01

This volume features seventeen extended conference abstracts corresponding to selected talks given by participants at the CRM research program “Automorphisms of Free Groups: Algorithms, Geometry and Dynamics”, which took place at the Centre de Recerca Matemàtica in Barcelona in fall 2012. Most of them are short articles giving preliminary presentations of new results not yet published in regular research journals. The articles are the result from a direct collaboration among active researchers in the area after working in a dynamic and productive atmosphere. The book is intended for established researchers in the area of Group Theory, as well as for PhD and postdoc students who wish to learn more about the latest advances in this active area of research.

General inverse problems for regular variation

DEFF Research Database (Denmark)

Damek, Ewa; Mikosch, Thomas Valentin; Rosinski, Jan

2014-01-01

Regular variation of distributional tails is known to be preserved by various linear transformations of some random structures. An inverse problem for regular variation aims at understanding whether the regular variation of a transformed random object is caused by regular variation of components ...

Temporal abstraction and temporal Bayesian networks in clinical domains: a survey.

Science.gov (United States)

Orphanou, Kalia; Stassopoulou, Athena; Keravnou, Elpida

2014-03-01

Temporal abstraction (TA) of clinical data aims to abstract and interpret clinical data into meaningful higher-level interval concepts. Abstracted concepts are used for diagnostic, prediction and therapy planning purposes. On the other hand, temporal Bayesian networks (TBNs) are temporal extensions of the known probabilistic graphical models, Bayesian networks. TBNs can represent temporal relationships between events and their state changes, or the evolution of a process, through time. This paper offers a survey on techniques/methods from these two areas that were used independently in many clinical domains (e.g. diabetes, hepatitis, cancer) for various clinical tasks (e.g. diagnosis, prognosis). A main objective of this survey, in addition to presenting the key aspects of TA and TBNs, is to point out important benefits from a potential integration of TA and TBNs in medical domains and tasks. The motivation for integrating these two areas is their complementary function: TA provides clinicians with high level views of data while TBNs serve as a knowledge representation and reasoning tool under uncertainty, which is inherent in all clinical tasks. Key publications from these two areas of relevance to clinical systems, mainly circumscribed to the latest two decades, are reviewed and classified. TA techniques are compared on the basis of: (a) knowledge acquisition and representation for deriving TA concepts and (b) methodology for deriving basic and complex temporal abstractions. TBNs are compared on the basis of: (a) representation of time, (b) knowledge representation and acquisition, (c) inference methods and the computational demands of the network, and (d) their applications in medicine. The survey performs an extensive comparative analysis to illustrate the separate merits and limitations of various TA and TBN techniques used in clinical systems with the purpose of anticipating potential gains through an integration of the two techniques, thus leading to a

Sleep Spindles in the Right Hemisphere Support Awareness of Regularities and Reflect Pre-Sleep Activations.

Science.gov (United States)

Yordanova, Juliana; Kolev, Vasil; Bruns, Eike; Kirov, Roumen; Verleger, Rolf

2017-11-01

The present study explored the sleep mechanisms which may support awareness of hidden regularities. Before sleep, 53 participants learned implicitly a lateralized variant of the serial response-time task in order to localize sensorimotor encoding either in the left or right hemisphere and induce implicit regularity representations. Electroencephalographic (EEG) activity was recorded at multiple electrodes during both task performance and sleep, searching for lateralized traces of the preceding activity during learning. Sleep EEG analysis focused on region-specific slow (9-12 Hz) and fast (13-16 Hz) sleep spindles during nonrapid eye movement sleep. Fast spindle activity at those motor regions that were activated during learning increased with the amount of postsleep awareness. Independently of side of learning, spindle activity at right frontal and fronto-central regions was involved: there, fast spindles increased with the transformation of sequence knowledge from implicit before sleep to explicit after sleep, and slow spindles correlated with individual abilities of gaining awareness. These local modulations of sleep spindles corresponded to regions with greater presleep activation in participants with postsleep explicit knowledge. Sleep spindle mechanisms are related to explicit awareness (1) by tracing the activation of motor cortical and right-hemisphere regions which had stronger involvement already during learning and (2) by recruitment of individually consolidated processing modules in the right hemisphere. The integration of different sleep spindle mechanisms with functional states during wake collectively supports the gain of awareness of previously experienced regularities, with a special role for the right hemisphere. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].

The Neural Correlates of Abstract and Concrete Words: Evidence from Brain-Damaged Patients

Directory of Open Access Journals (Sweden)

Giorgia Martello

2013-08-01

Full Text Available Neuropsychological and activation studies on the neural correlates of abstract and concrete words have produced contrasting results. The present study explores the anatomical substrates of abstract/concrete words in 22 brain-damaged patients with a single vascular lesion either in the right or left hemisphere. One hundred and twenty (60 concrete and 60 abstract noun triplets were used for a semantic similarity judgment task. We found a significant interaction in word type × group since left temporal brain-damaged patients performed significantly better with concrete than abstract words. Lesion mapping of patients with predominant temporal damage showed that the left superior and middle temporal gyri and the insula were the areas of major overlapping, while the anterior portion of the left temporal lobe was generally spared. Errors on abstract words mainly concerned (although at a non-significant level semantically associate targets, while in the case of concrete words, coordinate targets were significantly more impaired than associate ones. Our results suggest that the left superior and middle temporal gyri and the insula are crucial regions in processing abstract words. They also confirm the hypothesis of a semantic similarity vs. associative organization of concrete and abstract concepts.

Development of abstract mathematical reasoning: the case of algebra.

Science.gov (United States)

Susac, Ana; Bubic, Andreja; Vrbanc, Andrija; Planinic, Maja

2014-01-01

Algebra typically represents the students' first encounter with abstract mathematical reasoning and it therefore causes significant difficulties for students who still reason concretely. The aim of the present study was to investigate the developmental trajectory of the students' ability to solve simple algebraic equations. 311 participants between the ages of 13 and 17 were given a computerized test of equation rearrangement. Equations consisted of an unknown and two other elements (numbers or letters), and the operations of multiplication/division. The obtained results showed that younger participants are less accurate and slower in solving equations with letters (symbols) than those with numbers. This difference disappeared for older participants (16-17 years), suggesting that they had reached an abstract reasoning level, at least for this simple task. A corresponding conclusion arises from the analysis of their strategies which suggests that younger participants mostly used concrete strategies such as inserting numbers, while older participants typically used more abstract, rule-based strategies. These results indicate that the development of algebraic thinking is a process which unfolds over a long period of time. In agreement with previous research, we can conclude that, on average, children at the age of 15-16 transition from using concrete to abstract strategies while solving the algebra problems addressed within the present study. A better understanding of the timing and speed of students' transition from concrete arithmetic reasoning to abstract algebraic reasoning might help in designing better curricula and teaching materials that would ease that transition.

Continuum-regularized quantum gravity

International Nuclear Information System (INIS)

Chan Huesum; Halpern, M.B.

1987-01-01

The recent continuum regularization of d-dimensional Euclidean gravity is generalized to arbitrary power-law measure and studied in some detail as a representative example of coordinate-invariant regularization. The weak-coupling expansion of the theory illustrates a generic geometrization of regularized Schwinger-Dyson rules, generalizing previous rules in flat space and flat superspace. The rules are applied in a non-trivial explicit check of Einstein invariance at one loop: the cosmological counterterm is computed and its contribution is included in a verification that the graviton mass is zero. (orig.)

Regularization design for high-quality cone-beam CT of intracranial hemorrhage using statistical reconstruction

Science.gov (United States)

Dang, H.; Stayman, J. W.; Xu, J.; Sisniega, A.; Zbijewski, W.; Wang, X.; Foos, D. H.; Aygun, N.; Koliatsos, V. E.; Siewerdsen, J. H.

2016-03-01

Intracranial hemorrhage (ICH) is associated with pathologies such as hemorrhagic stroke and traumatic brain injury. Multi-detector CT is the current front-line imaging modality for detecting ICH (fresh blood contrast 40-80 HU, down to 1 mm). Flat-panel detector (FPD) cone-beam CT (CBCT) offers a potential alternative with a smaller scanner footprint, greater portability, and lower cost potentially well suited to deployment at the point of care outside standard diagnostic radiology and emergency room settings. Previous studies have suggested reliable detection of ICH down to 3 mm in CBCT using high-fidelity artifact correction and penalized weighted least-squared (PWLS) image reconstruction with a post-artifact-correction noise model. However, ICH reconstructed by traditional image regularization exhibits nonuniform spatial resolution and noise due to interaction between the statistical weights and regularization, which potentially degrades the detectability of ICH. In this work, we propose three regularization methods designed to overcome these challenges. The first two compute spatially varying certainty for uniform spatial resolution and noise, respectively. The third computes spatially varying regularization strength to achieve uniform "detectability," combining both spatial resolution and noise in a manner analogous to a delta-function detection task. Experiments were conducted on a CBCT test-bench, and image quality was evaluated for simulated ICH in different regions of an anthropomorphic head. The first two methods improved the uniformity in spatial resolution and noise compared to traditional regularization. The third exhibited the highest uniformity in detectability among all methods and best overall image quality. The proposed regularization provides a valuable means to achieve uniform image quality in CBCT of ICH and is being incorporated in a CBCT prototype for ICH imaging.

Geometric continuum regularization of quantum field theory

International Nuclear Information System (INIS)

Halpern, M.B.

1989-01-01

An overview of the continuum regularization program is given. The program is traced from its roots in stochastic quantization, with emphasis on the examples of regularized gauge theory, the regularized general nonlinear sigma model and regularized quantum gravity. In its coordinate-invariant form, the regularization is seen as entirely geometric: only the supermetric on field deformations is regularized, and the prescription provides universal nonperturbative invariant continuum regularization across all quantum field theory. 54 refs

Improved prediction of drug-target interactions using regularized least squares integrating with kernel fusion technique

Energy Technology Data Exchange (ETDEWEB)

Hao, Ming; Wang, Yanli, E-mail: ywang@ncbi.nlm.nih.gov; Bryant, Stephen H., E-mail: bryant@ncbi.nlm.nih.gov

2016-02-25

Identification of drug-target interactions (DTI) is a central task in drug discovery processes. In this work, a simple but effective regularized least squares integrating with nonlinear kernel fusion (RLS-KF) algorithm is proposed to perform DTI predictions. Using benchmark DTI datasets, our proposed algorithm achieves the state-of-the-art results with area under precision–recall curve (AUPR) of 0.915, 0.925, 0.853 and 0.909 for enzymes, ion channels (IC), G protein-coupled receptors (GPCR) and nuclear receptors (NR) based on 10 fold cross-validation. The performance can further be improved by using a recalculated kernel matrix, especially for the small set of nuclear receptors with AUPR of 0.945. Importantly, most of the top ranked interaction predictions can be validated by experimental data reported in the literature, bioassay results in the PubChem BioAssay database, as well as other previous studies. Our analysis suggests that the proposed RLS-KF is helpful for studying DTI, drug repositioning as well as polypharmacology, and may help to accelerate drug discovery by identifying novel drug targets. - Graphical abstract: Flowchart of the proposed RLS-KF algorithm for drug-target interaction predictions. - Highlights: • A nonlinear kernel fusion algorithm is proposed to perform drug-target interaction predictions. • Performance can further be improved by using the recalculated kernel. • Top predictions can be validated by experimental data.

Improved prediction of drug-target interactions using regularized least squares integrating with kernel fusion technique

International Nuclear Information System (INIS)

Hao, Ming; Wang, Yanli; Bryant, Stephen H.

2016-01-01

Identification of drug-target interactions (DTI) is a central task in drug discovery processes. In this work, a simple but effective regularized least squares integrating with nonlinear kernel fusion (RLS-KF) algorithm is proposed to perform DTI predictions. Using benchmark DTI datasets, our proposed algorithm achieves the state-of-the-art results with area under precision–recall curve (AUPR) of 0.915, 0.925, 0.853 and 0.909 for enzymes, ion channels (IC), G protein-coupled receptors (GPCR) and nuclear receptors (NR) based on 10 fold cross-validation. The performance can further be improved by using a recalculated kernel matrix, especially for the small set of nuclear receptors with AUPR of 0.945. Importantly, most of the top ranked interaction predictions can be validated by experimental data reported in the literature, bioassay results in the PubChem BioAssay database, as well as other previous studies. Our analysis suggests that the proposed RLS-KF is helpful for studying DTI, drug repositioning as well as polypharmacology, and may help to accelerate drug discovery by identifying novel drug targets. - Graphical abstract: Flowchart of the proposed RLS-KF algorithm for drug-target interaction predictions. - Highlights: • A nonlinear kernel fusion algorithm is proposed to perform drug-target interaction predictions. • Performance can further be improved by using the recalculated kernel. • Top predictions can be validated by experimental data.

Bypassing the Limits of Ll Regularization: Convex Sparse Signal Processing Using Non-Convex Regularization

Science.gov (United States)

Parekh, Ankit

Sparsity has become the basis of some important signal processing methods over the last ten years. Many signal processing problems (e.g., denoising, deconvolution, non-linear component analysis) can be expressed as inverse problems. Sparsity is invoked through the formulation of an inverse problem with suitably designed regularization terms. The regularization terms alone encode sparsity into the problem formulation. Often, the ℓ1 norm is used to induce sparsity, so much so that ℓ1 regularization is considered to be `modern least-squares'. The use of ℓ1 norm, as a sparsity-inducing regularizer, leads to a convex optimization problem, which has several benefits: the absence of extraneous local minima, well developed theory of globally convergent algorithms, even for large-scale problems. Convex regularization via the ℓ1 norm, however, tends to under-estimate the non-zero values of sparse signals. In order to estimate the non-zero values more accurately, non-convex regularization is often favored over convex regularization. However, non-convex regularization generally leads to non-convex optimization, which suffers from numerous issues: convergence may be guaranteed to only a stationary point, problem specific parameters may be difficult to set, and the solution is sensitive to the initialization of the algorithm. The first part of this thesis is aimed toward combining the benefits of non-convex regularization and convex optimization to estimate sparse signals more effectively. To this end, we propose to use parameterized non-convex regularizers with designated non-convexity and provide a range for the non-convex parameter so as to ensure that the objective function is strictly convex. By ensuring convexity of the objective function (sum of data-fidelity and non-convex regularizer), we can make use of a wide variety of convex optimization algorithms to obtain the unique global minimum reliably. The second part of this thesis proposes a non-linear signal

Using Tikhonov Regularization for Spatial Projections from CSR Regularized Spherical Harmonic GRACE Solutions

Science.gov (United States)

Save, H.; Bettadpur, S. V.

2013-12-01

It has been demonstrated before that using Tikhonov regularization produces spherical harmonic solutions from GRACE that have very little residual stripes while capturing all the signal observed by GRACE within the noise level. This paper demonstrates a two-step process and uses Tikhonov regularization to remove the residual stripes in the CSR regularized spherical harmonic coefficients when computing the spatial projections. We discuss methods to produce mass anomaly grids that have no stripe features while satisfying the necessary condition of capturing all observed signal within the GRACE noise level.

Task-related Interactions between Kindergarten Children and their Teachers: The Role of Emotional Security

OpenAIRE

Thijs, Jochem T.; Koomen, Helma M.Y.

2008-01-01

This study examined the emotional security of kindergarten children in dyadic task-related interactions with their teachers. In particular, it examined the interrelations between security, task behaviours (persistence and independence), social inhibition, and teachers’ support. Participants were 79 kindergartners (mean age = 69.7 months) and their 40 regular teachers. Children were selected to approach a normal distribution of social inhibition. Children and teachers were filmed during a dyad...

Physical and Chemical Environmental Abstraction Model

International Nuclear Information System (INIS)

Nowak, E.

2000-01-01

As directed by a written development plan (CRWMS M and O 1999a), Task 1, an overall conceptualization of the physical and chemical environment (P/CE) in the emplacement drift is documented in this Analysis/Model Report (AMR). Included are the physical components of the engineered barrier system (EBS). The intended use of this descriptive conceptualization is to assist the Performance Assessment Department (PAD) in modeling the physical and chemical environment within a repository drift. It is also intended to assist PAD in providing a more integrated and complete in-drift geochemical model abstraction and to answer the key technical issues raised in the U.S. Nuclear Regulatory Commission (NRC) Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE) Revision 2 (NRC 1999). EBS-related features, events, and processes (FEPs) have been assembled and discussed in ''EBS FEPs/Degradation Modes Abstraction'' (CRWMS M and O 2000a). Reference AMRs listed in Section 6 address FEPs that have not been screened out. This conceptualization does not directly address those FEPs. Additional tasks described in the written development plan are recommended for future work in Section 7.3. To achieve the stated purpose, the scope of this document includes: (1) the role of in-drift physical and chemical environments in the Total System Performance Assessment (TSPA) (Section 6.1); (2) the configuration of engineered components (features) and critical locations in drifts (Sections 6.2.1 and 6.3, portions taken from EBS Radionuclide Transport Abstraction (CRWMS M and O 2000b)); (3) overview and critical locations of processes that can affect P/CE (Section 6.3); (4) couplings and relationships among features and processes in the drifts (Section 6.4); and (5) identities and uses of parameters transmitted to TSPA by some of the reference AMRs (Section 6.5). This AMR originally considered a design with backfill, and is now being updated (REV 00 ICN1) to address

Full Text Searching and Customization in the NASA ADS Abstract Service

Science.gov (United States)

Eichhorn, G.; Accomazzi, A.; Grant, C. S.; Kurtz, M. J.; Henneken, E. A.; Thompson, D. M.; Murray, S. S.

2004-01-01

The NASA-ADS Abstract Service provides a sophisticated search capability for the literature in Astronomy, Planetary Sciences, Physics/Geophysics, and Space Instrumentation. The ADS is funded by NASA and access to the ADS services is free to anybody worldwide without restrictions. It allows the user to search the literature by author, title, and abstract text. The ADS database contains over 3.6 million references, with 965,000 in the Astronomy/Planetary Sciences database, and 1.6 million in the Physics/Geophysics database. 2/3 of the records have full abstracts, the rest are table of contents entries (titles and author lists only). The coverage for the Astronomy literature is better than 95% from 1975. Before that we cover all major journals and many smaller ones. Most of the journal literature is covered back to volume 1. We now get abstracts on a regular basis from most journals. Over the last year we have entered basically all conference proceedings tables of contents that are available at the Harvard Smithsonian Center for Astrophysics library. This has greatly increased the coverage of conference proceedings in the ADS. The ADS also covers the ArXiv Preprints. We download these preprints every night and index all the preprints. They can be searched either together with the other abstracts or separately. There are currently about 260,000 preprints in that database. In January 2004 we have introduced two new services, full text searching and a personal notification service called "myADS". As all other ADS services, these are free to use for anybody.

Regularized image denoising based on spectral gradient optimization

International Nuclear Information System (INIS)

Lukić, Tibor; Lindblad, Joakim; Sladoje, Nataša

2011-01-01

Image restoration methods, such as denoising, deblurring, inpainting, etc, are often based on the minimization of an appropriately defined energy function. We consider energy functions for image denoising which combine a quadratic data-fidelity term and a regularization term, where the properties of the latter are determined by a used potential function. Many potential functions are suggested for different purposes in the literature. We compare the denoising performance achieved by ten different potential functions. Several methods for efficient minimization of regularized energy functions exist. Most are only applicable to particular choices of potential functions, however. To enable a comparison of all the observed potential functions, we propose to minimize the objective function using a spectral gradient approach; spectral gradient methods put very weak restrictions on the used potential function. We present and evaluate the performance of one spectral conjugate gradient and one cyclic spectral gradient algorithm, and conclude from experiments that both are well suited for the task. We compare the performance with three total variation-based state-of-the-art methods for image denoising. From the empirical evaluation, we conclude that denoising using the Huber potential (for images degraded by higher levels of noise; signal-to-noise ratio below 10 dB) and the Geman and McClure potential (for less noisy images), in combination with the spectral conjugate gradient minimization algorithm, shows the overall best performance

The use of assistive technology resources for disabled children in regular schooling: the teachers’ perception

Directory of Open Access Journals (Sweden)

2012-12-01

Full Text Available The national School Census revealed that 702,603 disabled people were enrolled in regular educationin 2010. The use of assistive technology resources in the school context has been indicated to favor the executionof tasks and the access to educational content and school environments and, consequently, help disabledindividuals’ learning. However, there are few studies showing the impact of these resources in the educationprocess of children with physical disabilities. The aim of this study was to identify, from the teacher’s viewpoint,the contributions and difficulties in the use of technology resources with students with cerebral palsy, focusingon those with severe motor impairment, attending regular education. The study included five teachers of these students who were using assistive technology resources in the execution of writing and/or communicationassignments. Semi-structured interviews were conducted and data were analyzed following the CollectiveSubject Discourse (CSD technique. Results indicated that assistive technology resources are already includedin regular schools and that they have brought contributions to the education process of children with cerebralpalsy in regular class; nevertheless, they are being implemented without systematization, monitoring and/orpartnerships. The study pointed to the need to consider the opinions and requirements of the people involved inthe context where the use of technology is inserted.

Concept of Triangle: Examples of Mathematical Abstraction in Two Different Contexts

Directory of Open Access Journals (Sweden)

Farida Nurhasanah

2017-02-01

Full Text Available In attempt to explain how students learning geometry in concept of triangle, this study explore the learning process of students and the process of solving geometry problems in the topic of triangle.  As known as one of the domain in school of mathematics, geometry has abstract notions to be learnt so that all those notions cannot be just transferred into students’ mind like a bunch of information that should be memorized. Students need to construct those concepts during their learning process. This process of knowledge construction can be considered as an abstraction process. This study aimed to qualitatively compare students’ abstraction process who learn topic of triangle in conventional method of teaching and in van Hiele model of teaching aided by Geometers’ sketchpad. Subjects of this study were junir high school students in grade 7. Based on the aims of this study, this is a qualitative study with grounded theory design. Data were collected through classroom observation, test, and task-based interview. Results of the study show that theoretical abstraction processes tend to dominate classrom with conventional method of teaching while classroom with van Hiele model of teaching aided by Geometers’ sketchpad accommodated empirical abstraction process of the students

Some approximating formulae to the solution of an abstract evolution problem

International Nuclear Information System (INIS)

Ngongo, M.E.

1991-12-01

We consider discrete semigroups of operators associated with the first two primary sub-families of A-acceptable Norsett's rational approximations to e q , S 1 (γ;q) and S 2 (γ;q) with q is an element of C and γ a real parameter, and construct approximating formulae to the solution of an abstract evolution problem. The study of convergence is reduced to exploiting previous fundamental results of the author for this class of semigroups and this results, for associated numerical schemes, in a convergence independent of the regularity of the data of the problem. (author). 17 refs, 3 tabs

Awareness of Knowledge or Awareness of Processing? Implications for Sleep-Related Memory Consolidation

OpenAIRE

Yordanova, Juliana; Kolev, Vasil; Verleger, Rolf

2009-01-01

The present study assessed the effects of awareness at encoding on off-line learning during sleep. A new framework is suggested according to which two aspects of awareness are distinguished: awareness of task information, and awareness of task processing. The number reduction task (NRT) was employed because it has two levels of organization, an overt one based on explicit knowledge of task instructions, and a covert one based on hidden abstract regularities of task structure (implicit knowled...

Grounding abstractness: Abstract concepts and the activation of the mouth

Directory of Open Access Journals (Sweden)

Anna M Borghi

2016-10-01

Full Text Available One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth. While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts.

Regularities of Multifractal Measures

Indian Academy of Sciences (India)

First, we prove the decomposition theorem for the regularities of multifractal Hausdorff measure and packing measure in R R d . This decomposition theorem enables us to split a set into regular and irregular parts, so that we can analyze each separately, and recombine them without affecting density properties. Next, we ...

Adaptive Regularization of Neural Classifiers

DEFF Research Database (Denmark)

Andersen, Lars Nonboe; Larsen, Jan; Hansen, Lars Kai

1997-01-01

We present a regularization scheme which iteratively adapts the regularization parameters by minimizing the validation error. It is suggested to use the adaptive regularization scheme in conjunction with optimal brain damage pruning to optimize the architecture and to avoid overfitting. Furthermo......, we propose an improved neural classification architecture eliminating an inherent redundancy in the widely used SoftMax classification network. Numerical results demonstrate the viability of the method...

Condition Number Regularized Covariance Estimation.

Science.gov (United States)

Won, Joong-Ho; Lim, Johan; Kim, Seung-Jean; Rajaratnam, Bala

2013-06-01

Estimation of high-dimensional covariance matrices is known to be a difficult problem, has many applications, and is of current interest to the larger statistics community. In many applications including so-called the "large p small n " setting, the estimate of the covariance matrix is required to be not only invertible, but also well-conditioned. Although many regularization schemes attempt to do this, none of them address the ill-conditioning problem directly. In this paper, we propose a maximum likelihood approach, with the direct goal of obtaining a well-conditioned estimator. No sparsity assumption on either the covariance matrix or its inverse are are imposed, thus making our procedure more widely applicable. We demonstrate that the proposed regularization scheme is computationally efficient, yields a type of Steinian shrinkage estimator, and has a natural Bayesian interpretation. We investigate the theoretical properties of the regularized covariance estimator comprehensively, including its regularization path, and proceed to develop an approach that adaptively determines the level of regularization that is required. Finally, we demonstrate the performance of the regularized estimator in decision-theoretic comparisons and in the financial portfolio optimization setting. The proposed approach has desirable properties, and can serve as a competitive procedure, especially when the sample size is small and when a well-conditioned estimator is required.

Communicating with the crowd: speakers use abstract messages when addressing larger audiences.

Science.gov (United States)

Joshi, Priyanka D; Wakslak, Cheryl J

2014-02-01

Audience characteristics often shape communicators' message framing. Drawing from construal level theory, we suggest that when speaking to many individuals, communicators frame messages in terms of superordinate characteristics that focus attention on the essence of the message. On the other hand, when communicating with a single individual, communicators increasingly describe events and actions in terms of their concrete details. Using different communication tasks and measures of construal, we show that speakers communicating with many individuals, compared with 1 person, describe events more abstractly (Study 1), describe themselves as more trait-like (Study 2), and use more desirability-related persuasive messages (Study 3). Furthermore, speakers' motivation to communicate with their audience moderates their tendency to frame messages based on audience size (Studies 3 and 4). This audience-size abstraction effect is eliminated when a large audience is described as homogeneous, suggesting that people use abstract construal strategically in order to connect across a disparate group of individuals (Study 5). Finally, we show that participants' experienced fluency in communication is influenced by the match between message abstraction and audience size (Study 6).

Factors associated with regular physical exercise and consumption of fruits and vegetables among Mexican older adults

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Svetlana V. Doubova

2016-09-01

Full Text Available Abstract Background To analyze the factors associated with regular physical exercise and routine consumption of fruits and vegetables, and both healthy behaviors among Mexican older adults. Methods We conducted a secondary data analysis of the baseline data (2014 of the Study on Obesity, Sarcopenia and Fragility in older adults affiliated with the Mexican Institute of Social Security. The study included 948 adults who were ≥60 years of age. Multiple Poisson regression was performed. Results Routine consumption of fruits and vegetables was reported by 53.8 % of older adults, 42.7 % reported engaging in regular physical exercise and 23.1 % reported participating in both types of healthy behaviors. Women, adults with a stable income, those with a self-perception of good health and those with a history of physical exercise at the age of 50 years had an increased likelihood of engaging in healthy eating and regular physical activity. Conclusions Many older adults do not routinely consume fruits and vegetables or engage in regular physical exercise despite the fact that most have a fixed income and a social network. It is relevant to conduct research-based interventions that take into account the contextual factors to promote healthy behaviors.

L1-norm locally linear representation regularization multi-source adaptation learning.

Science.gov (United States)

Tao, Jianwen; Wen, Shiting; Hu, Wenjun

2015-09-01

In most supervised domain adaptation learning (DAL) tasks, one has access only to a small number of labeled examples from target domain. Therefore the success of supervised DAL in this "small sample" regime needs the effective utilization of the large amounts of unlabeled data to extract information that is useful for generalization. Toward this end, we here use the geometric intuition of manifold assumption to extend the established frameworks in existing model-based DAL methods for function learning by incorporating additional information about the target geometric structure of the marginal distribution. We would like to ensure that the solution is smooth with respect to both the ambient space and the target marginal distribution. In doing this, we propose a novel L1-norm locally linear representation regularization multi-source adaptation learning framework which exploits the geometry of the probability distribution, which has two techniques. Firstly, an L1-norm locally linear representation method is presented for robust graph construction by replacing the L2-norm reconstruction measure in LLE with L1-norm one, which is termed as L1-LLR for short. Secondly, considering the robust graph regularization, we replace traditional graph Laplacian regularization with our new L1-LLR graph Laplacian regularization and therefore construct new graph-based semi-supervised learning framework with multi-source adaptation constraint, which is coined as L1-MSAL method. Moreover, to deal with the nonlinear learning problem, we also generalize the L1-MSAL method by mapping the input data points from the input space to a high-dimensional reproducing kernel Hilbert space (RKHS) via a nonlinear mapping. Promising experimental results have been obtained on several real-world datasets such as face, visual video and object. Copyright © 2015 Elsevier Ltd. All rights reserved.

Driving after brain injury: Does dual-task modality matter?

Science.gov (United States)

Vickers, Kayci L; Schultheis, Maria T; Manning, Kevin J

2018-01-01

Virtual reality technology allows neuropsychologists to examine complex, real-world behaviors with high ecological validity and can provide an understanding of the impact of demanding dual-tasks on driving performance. We hypothesized that a task imposing high cognitive and physical demands (coin-sorting) would result in the greatest reduction in driving maintenance performance. Twenty participants with acquired brain injury and 28 healthy controls were included in the current study. All participants were licensed and drove regularly. Participants completed two standardized VRDS drives: (1) a baseline drive with no distractions, and (2) the same route with three, counterbalanced dual-tasks representing differing demands. A series of 3 (Task)×2 (Group) ANOVAs revealed that the ABI group tended to go slower than the HC group in the presence of a dual-task, F (1, 111) = 6.24, p = 0.01. Importantly, the ABI group also showed greater variability in speed, F (1, 110) = 10.97, p < 0.01, and lane position, F (1, 108) = 7.81, p < 0.01, an effect driven by dual-tasks with both a cognitive and motor demand. These results indicate that long-term driving difficulties following ABI are subtle and likely due to reduced cognitive resources.

Dual-Task Assessment Protocols in Concussion Assessment: A Systematic Literature Review.

Science.gov (United States)

Kleiner, Michelle; Wong, Lynne; Dubé, Alexandra; Wnuk, Katie; Hunter, Susan W; Graham, Laura J

2018-02-01

Study Design Systematic review. Background When assessed in isolation, balance and neurocognitive testing may not be sufficiently responsive to capture changes that occur with concussion. Normal daily activities require simultaneous cognitive and physical demands. Therefore, a dual-task assessment paradigm should be considered to identify performance deficits. Objectives To evaluate the literature and to identify dual-task testing protocols associated with changes in gait after concussion. Methods A systematic review of articles of individuals with concussion who underwent dual-task testing with a combination of motor and cognitive tasks was conducted. The AMED, CINAHL, Embase, PsycINFO, PubMed, Scopus, SPORTDiscus, and Web of Science databases and gray literature were searched from inception to January 29, 2017. Title and abstract, full-text, and quality review and data abstraction were performed by 2 independent reviewers. Results Twenty-four articles met the inclusion criteria. Eleven articles reported decreased gait velocity and increased medial-lateral displacement for individuals with concussion during dual-task conditions. Overall, included articles were of poor to moderate methodological quality. Fifteen articles used the same participants and data sets, creating a threat to validity and limiting the ability to make conclusions. Conclusion A deterioration in gait performance during dual-task testing is present among people with concussion. Specific recommendations for the use of a dual-task protocol to assess individuals with suspected concussion injury in a clinical setting have yet to be determined. J Orthop Sports Phys Ther 2018;48(2):87-103. Epub 7 Nov 2017. doi:10.2519/jospt.2018.7432.

Relation between task complexity and variability of procedure progression during an emergency operation

International Nuclear Information System (INIS)

Kim, Yochan; Park, Jinkyun; Jung, Wondea

2013-01-01

Highlights: • The relation between task complexity and the variability of procedure progression was investigated. • The two quantitative measures, TACOM and VPP, were applied to this study. • The task complexity was positively related with the operator’s procedural variability. • The VPP measure can be useful for explaining the operator’s behaviors. - Abstract: In this study, the relation between task complexity and variability of procedure progression during an emergency operation was investigated by comparing the two quantitative measures. To this end, the TACOM measure and VPP measure were applied to evaluate the complexity of tasks and variability of procedure progression, respectively. The TACOM scores and VPP scores were obtained for 60 tasks in the OPERA database, and a correlation analysis between two measures and a multiple regression analysis between the sub-measures of the TACOM measure and VPP measure were conducted. The results showed that the TACOM measure is positively associated with the VPP measure, and the abstraction hierarchy complexity mainly affected the variability among the sub-measures of TACOM. From these findings, it was discussed that the task complexity is related to an operator’s procedural variability and VPP measure can be useful for explaining the operator’s behaviors

Gait stability and variability measures show effects of impaired cognition and dual tasking in frail people

Directory of Open Access Journals (Sweden)

de Vries Oscar J

2011-01-01

Full Text Available Abstract Background Falls in frail elderly are a common problem with a rising incidence. Gait and postural instability are major risk factors for falling, particularly in geriatric patients. As walking requires attention, cognitive impairments are likely to contribute to an increased fall risk. An objective quantification of gait and balance ability is required to identify persons with a high tendency to fall. Recent studies have shown that stride variability is increased in elderly and under dual task condition and might be more sensitive to detect fall risk than walking speed. In the present study we complemented stride related measures with measures that quantify trunk movement patterns as indicators of dynamic balance ability during walking. The aim of the study was to quantify the effect of impaired cognition and dual tasking on gait variability and stability in geriatric patients. Methods Thirteen elderly with dementia (mean age: 82.6 ± 4.3 years and thirteen without dementia (79.4 ± 5.55 recruited from a geriatric day clinic, walked at self-selected speed with and without performing a verbal dual task. The Mini Mental State Examination and the Seven Minute Screen were administered. Trunk accelerations were measured with an accelerometer. In addition to walking speed, mean, and variability of stride times, gait stability was quantified using stochastic dynamical measures, namely regularity (sample entropy, long range correlations and local stability exponents of trunk accelerations. Results Dual tasking significantly (p Conclusions The observed trunk adaptations were a consistent instability factor. These results support the concept that changes in cognitive functions contribute to changes in the variability and stability of the gait pattern. Walking under dual task conditions and quantifying gait using dynamical parameters can improve detecting walking disorders and might help to identify those elderly who are able to adapt walking

Condition Number Regularized Covariance Estimation*

Science.gov (United States)

Won, Joong-Ho; Lim, Johan; Kim, Seung-Jean; Rajaratnam, Bala

2012-01-01

Estimation of high-dimensional covariance matrices is known to be a difficult problem, has many applications, and is of current interest to the larger statistics community. In many applications including so-called the “large p small n” setting, the estimate of the covariance matrix is required to be not only invertible, but also well-conditioned. Although many regularization schemes attempt to do this, none of them address the ill-conditioning problem directly. In this paper, we propose a maximum likelihood approach, with the direct goal of obtaining a well-conditioned estimator. No sparsity assumption on either the covariance matrix or its inverse are are imposed, thus making our procedure more widely applicable. We demonstrate that the proposed regularization scheme is computationally efficient, yields a type of Steinian shrinkage estimator, and has a natural Bayesian interpretation. We investigate the theoretical properties of the regularized covariance estimator comprehensively, including its regularization path, and proceed to develop an approach that adaptively determines the level of regularization that is required. Finally, we demonstrate the performance of the regularized estimator in decision-theoretic comparisons and in the financial portfolio optimization setting. The proposed approach has desirable properties, and can serve as a competitive procedure, especially when the sample size is small and when a well-conditioned estimator is required. PMID:23730197

On the relationships between generative encodings, regularity, and learning abilities when evolving plastic artificial neural networks.

Directory of Open Access Journals (Sweden)

Paul Tonelli

Full Text Available A major goal of bio-inspired artificial intelligence is to design artificial neural networks with abilities that resemble those of animal nervous systems. It is commonly believed that two keys for evolving nature-like artificial neural networks are (1 the developmental process that links genes to nervous systems, which enables the evolution of large, regular neural networks, and (2 synaptic plasticity, which allows neural networks to change during their lifetime. So far, these two topics have been mainly studied separately. The present paper shows that they are actually deeply connected. Using a simple operant conditioning task and a classic evolutionary algorithm, we compare three ways to encode plastic neural networks: a direct encoding, a developmental encoding inspired by computational neuroscience models, and a developmental encoding inspired by morphogen gradients (similar to HyperNEAT. Our results suggest that using a developmental encoding could improve the learning abilities of evolved, plastic neural networks. Complementary experiments reveal that this result is likely the consequence of the bias of developmental encodings towards regular structures: (1 in our experimental setup, encodings that tend to produce more regular networks yield networks with better general learning abilities; (2 whatever the encoding is, networks that are the more regular are statistically those that have the best learning abilities.

Attitudes and actions of asthma patients on regular maintenance therapy: the INSPIRE study

Directory of Open Access Journals (Sweden)

Myrseth Sven-Erik

2006-06-01

Full Text Available Abstract Background This study examined the attitudes and actions of 3415 physician-recruited adults aged ≥ 16 years with asthma in eleven countries who were prescribed regular maintenance therapy with inhaled corticosteroids or inhaled corticosteroids plus long-acting β2-agonists. Methods Structured interviews were conducted to assess medication use, asthma control, and patients' ability to recognise and self-manage worsening asthma. Results Despite being prescribed regular maintenance therapy, 74% of patients used short-acting β2-agonists daily and 51% were classified by the Asthma Control Questionnaire as having uncontrolled asthma. Even patients with well-controlled asthma reported an average of 6 worsenings/year. The mean period from the onset to the peak symptoms of a worsening was 5.1 days. Although most patients recognised the early signs of worsenings, the most common response was to increase short-acting β2-agonist use; inhaled corticosteroids were increased to a lesser extent at the peak of a worsening. Conclusion Previous studies of this nature have also reported considerable patient morbidity, but in those studies approximately three-quarters of patients were not receiving regular maintenance therapy and not all had a physician-confirmed diagnosis of asthma. This study shows that patients with asthma receiving regular maintenance therapy still have high levels of inadequately controlled asthma. The study also shows that patients recognise deteriorating asthma control and adjust their medication during episodes of worsening. However, they often adjust treatment in an inappropriate manner, which represents a window of missed opportunity.

Relationship with the Regularity of Visits Complications of Hypertension in Patients more than 45 years old

Directory of Open Access Journals (Sweden)

Wahyu Wijayanto

2014-01-01

Full Text Available ABSTRACT Hypertension being a risk factor for the entrance of various degenerative diseases such as coronary heart disease, stroke and other vascular Penyait. One factor that may increase the risk of hypertension one of them is poor lifestyle such as smoking, excessive consumption of salt in the diet and lack of exercise. This study was conducted to determine the level of knowledge about the relationship with the regularity of visits Complications of Hypertension Hypertension in Patients 45 years of age at the Tembok Dukuh  health center at Surabaya. The study was an observational cross-sectional study design. Sample size were 48 people that hypertensive patients more than 45 years old  who were treated at the Tembok Dukuh  health center. Independent variables, namely knowledge about the complications of hypertension patients and dependent variable is the regularity of visits to theTembok Dukuh health center patients with hypertension  Data analysis using the crosstab tes The results with cross-tabulation (crosstab can be seen as many as 30 people from 48 respondents have less knowledge and affect the regularity of visits to the Tembok Dukuh health center. The conclusion can be drawn that most hypertensive patients more than 45 years old whose came to Tembok Dukuh  health centers has less knowledge about hypertension complications that result in hypertensive patients regularity of visits decreased Keyword : hypertension, knowledge, regularity of visits

Multi-Task Convolutional Neural Network for Pose-Invariant Face Recognition

Science.gov (United States)

Yin, Xi; Liu, Xiaoming

2018-02-01

This paper explores multi-task learning (MTL) for face recognition. We answer the questions of how and why MTL can improve the face recognition performance. First, we propose a multi-task Convolutional Neural Network (CNN) for face recognition where identity classification is the main task and pose, illumination, and expression estimations are the side tasks. Second, we develop a dynamic-weighting scheme to automatically assign the loss weight to each side task, which is a crucial problem in MTL. Third, we propose a pose-directed multi-task CNN by grouping different poses to learn pose-specific identity features, simultaneously across all poses. Last but not least, we propose an energy-based weight analysis method to explore how CNN-based MTL works. We observe that the side tasks serve as regularizations to disentangle the variations from the learnt identity features. Extensive experiments on the entire Multi-PIE dataset demonstrate the effectiveness of the proposed approach. To the best of our knowledge, this is the first work using all data in Multi-PIE for face recognition. Our approach is also applicable to in-the-wild datasets for pose-invariant face recognition and achieves comparable or better performance than state of the art on LFW, CFP, and IJB-A datasets.

Autistic children and the object permanence task.

Science.gov (United States)

Adrien, J L; Tanguay, P; Barthélémy, C; Martineaú, J; Perrot, A; Hameury, L; Sauvage, D

1993-01-01

Many mentally retarded autistic children can understand the concept of object permanence, but, in comparison to developmental-age matched normal children, the behavioral strategies they employ in carrying out the Casati-Lezine Object Permanence Test are deficient and lead to failure. These deficiencies appear unrelated to interference of stereotypic or other bizarre behavior in task performance. Similar problem-solving deficiencies can be found in mentally retarded children who are not autistic, suggesting that the deficiencies themselves are less related to the social-communication deficits of autistic children, but more to the general problem-solving difficulties found in children with a lower developmental quotient. Nevertheless, the qualitative analysis of results shows a tendency in autistic children, despite their better developmental level, to use less coordinated and regular sequences to solve the task than normal or mentally retarded children.

Learning About Time Within the Spinal Cord II: Evidence that Temporal Regularity is Encoded by a Spinal Oscillator

Directory of Open Access Journals (Sweden)

Kuan Hsien Lee

2016-02-01

Full Text Available How a stimulus impacts spinal cord function depends upon temporal relations. When intermittent noxious stimulation (shock is applied and the interval between shock pulses is varied (unpredictable, it induces a lasting alteration that inhibits adaptive learning. If the same stimulus is applied in a temporally regular (predictable manner, the capacity to learn is preserved and a protective/restorative effect is engaged that counters the adverse effect of variable stimulation. Sensitivity to temporal relations implies a capacity to encode time. This study explores how spinal neurons discriminate variable and fixed spaced stimulation. Communication with the brain was blocked by means of a spinal transection and adaptive capacity was tested using an instrumental learning task. In this task, subjects must learn to maintain a hind limb in a flexed position to minimize shock exposure. To evaluate the possibility that a distinct class of afferent fibers provide a sensory cue for regularity, we manipulated the temporal relation between shocks given to two dermatomes (leg and tail. Evidence for timing emerged when the stimuli were applied in a coherent manner across dermatomes, implying that a central (spinal process detects regularity. Next, we show that fixed spaced stimulation has a restorative effect when half the physical stimuli are randomly omitted, as long as the stimuli remain in phase, suggesting that stimulus regularity is encoded by an internal oscillator Research suggests that the oscillator that drives the tempo of stepping depends upon neurons within the rostral lumbar (L1-L2 region. Disrupting communication with the L1-L2 tissue by means of a L3 transection eliminated the restorative effect of fixed spaced stimulation. Implications of the results for step training and rehabilitation after injury are discussed.

Brief Report: Impaired Flexible Item Selection Task (FIST) in School-Age Children with Autism Spectrum Disorders

Science.gov (United States)

Yerys, Benjamin E.; Wolff, Brian C.; Moody, Eric; Pennington, Bruce F.; Hepburn, Susan L.

2012-01-01

Cognitive flexibility has been measured with inductive reasoning or explicit rule tasks in individuals with autism spectrum disorders (ASD). The "Flexible Item Selection Task" (FIST) differs from previous cognitive flexibility tasks in ASD research by giving children an abstract, ambiguous rule to switch. The ASD group (N = 22; Mean age = 8.28…

Can abstract screening workload be reduced using text mining? User experiences of the tool Rayyan.

Science.gov (United States)

Olofsson, Hanna; Brolund, Agneta; Hellberg, Christel; Silverstein, Rebecca; Stenström, Karin; Österberg, Marie; Dagerhamn, Jessica

2017-09-01

One time-consuming aspect of conducting systematic reviews is the task of sifting through abstracts to identify relevant studies. One promising approach for reducing this burden uses text mining technology to identify those abstracts that are potentially most relevant for a project, allowing those abstracts to be screened first. To examine the effectiveness of the text mining functionality of the abstract screening tool Rayyan. User experiences were collected. Rayyan was used to screen abstracts for 6 reviews in 2015. After screening 25%, 50%, and 75% of the abstracts, the screeners logged the relevant references identified. A survey was sent to users. After screening half of the search result with Rayyan, 86% to 99% of the references deemed relevant to the study were identified. Of those studies included in the final reports, 96% to 100% were already identified in the first half of the screening process. Users rated Rayyan 4.5 out of 5. The text mining function in Rayyan successfully helped reviewers identify relevant studies early in the screening process. Copyright © 2017 John Wiley & Sons, Ltd.

Moving beyond Solving for "x": Teaching Abstract Algebra in a Liberal Arts Mathematics Course

Science.gov (United States)

Cook, John Paul

2015-01-01

This paper details an inquiry-based approach for teaching the basic notions of rings and fields to liberal arts mathematics students. The task sequence seeks to encourage students to identify and comprehend core concepts of introductory abstract algebra by thinking like mathematicians; that is, by investigating an open-ended mathematical context,…

Regular-, irregular-, and pseudo-character processing in Chinese: The regularity effect in normal adult readers

Directory of Open Access Journals (Sweden)

Dustin Kai Yan Lau

2014-03-01

Full Text Available Background Unlike alphabetic languages, Chinese uses a logographic script. However, the pronunciation of many character’s phonetic radical has the same pronunciation as the character as a whole. These are considered regular characters and can be read through a lexical non-semantic route (Weekes & Chen, 1999. Pseudocharacters are another way to study this non-semantic route. A pseudocharacter is the combination of existing semantic and phonetic radicals in their legal positions resulting in a non-existing character (Ho, Chan, Chung, Lee, & Tsang, 2007. Pseudocharacters can be pronounced by direct derivation from the sound of its phonetic radical. Conversely, if the pronunciation of a character does not follow that of the phonetic radical, it is considered as irregular and can only be correctly read through the lexical-semantic route. The aim of the current investigation was to examine reading aloud in normal adults. We hypothesized that the regularity effect, previously described for alphabetical scripts and acquired dyslexic patients of Chinese (Weekes & Chen, 1999; Wu, Liu, Sun, Chromik, & Zhang, 2014, would also be present in normal adult Chinese readers. Method Participants. Thirty (50% female native Hong Kong Cantonese speakers with a mean age of 19.6 years and a mean education of 12.9 years. Stimuli. Sixty regular-, 60 irregular-, and 60 pseudo-characters (with at least 75% of name agreement in Chinese were matched by initial phoneme, number of strokes and family size. Additionally, regular- and irregular-characters were matched by frequency (low and consistency. Procedure. Each participant was asked to read aloud the stimuli presented on a laptop using the DMDX software. The order of stimuli presentation was randomized. Data analysis. ANOVAs were carried out by participants and items with RTs and errors as dependent variables and type of stimuli (regular-, irregular- and pseudo-character as repeated measures (F1 or between subject�

J-regular rings with injectivities

OpenAIRE

Shen, Liang

2010-01-01

A ring $R$ is called a J-regular ring if R/J(R) is von Neumann regular, where J(R) is the Jacobson radical of R. It is proved that if R is J-regular, then (i) R is right n-injective if and only if every homomorphism from an $n$-generated small right ideal of $R$ to $R_{R}$ can be extended to one from $R_{R}$ to $R_{R}$; (ii) R is right FP-injective if and only if R is right (J, R)-FP-injective. Some known results are improved.

Machine Shop Suggested Job and Task Sheets. Part II. 21 Advanced Jobs.

Science.gov (United States)

Texas A and M Univ., College Station. Vocational Instructional Services.

This volume consists of advanced job and task sheets adaptable for use in the regular vocational industrial education programs for the training of machinists and machine shop operators. Twenty-one advanced machine shop job sheets are included. Some or all of this material is provided for each job: an introductory sheet with aim, checking…

Machine Shop Suggested Job and Task Sheets. Part I. 25 Elementary Jobs.

Science.gov (United States)

Texas A and M Univ., College Station. Vocational Instructional Services.

This volume consists of elementary job and task sheets adaptable for use in the regular vocational industrial education programs for the training of machinists and machine shop operators. Twenty-five simple machine shop job sheets are included. Some or all of this material is provided for each job sheet: an introductory sheet with aim, checking…

Iterative Regularization with Minimum-Residual Methods

DEFF Research Database (Denmark)

Jensen, Toke Koldborg; Hansen, Per Christian

2007-01-01

subspaces. We provide a combination of theory and numerical examples, and our analysis confirms the experience that MINRES and MR-II can work as general regularization methods. We also demonstrate theoretically and experimentally that the same is not true, in general, for GMRES and RRGMRES their success......We study the regularization properties of iterative minimum-residual methods applied to discrete ill-posed problems. In these methods, the projection onto the underlying Krylov subspace acts as a regularizer, and the emphasis of this work is on the role played by the basis vectors of these Krylov...... as regularization methods is highly problem dependent....

Iterative regularization with minimum-residual methods

DEFF Research Database (Denmark)

Jensen, Toke Koldborg; Hansen, Per Christian

2006-01-01

subspaces. We provide a combination of theory and numerical examples, and our analysis confirms the experience that MINRES and MR-II can work as general regularization methods. We also demonstrate theoretically and experimentally that the same is not true, in general, for GMRES and RRGMRES - their success......We study the regularization properties of iterative minimum-residual methods applied to discrete ill-posed problems. In these methods, the projection onto the underlying Krylov subspace acts as a regularizer, and the emphasis of this work is on the role played by the basis vectors of these Krylov...... as regularization methods is highly problem dependent....

Neural correlates of visualizations of concrete and abstract words in preschool children: A developmental embodied approach

Directory of Open Access Journals (Sweden)

Amedeo eD'angiulli

2015-06-01

Full Text Available The neural correlates of visualization underlying word comprehension were examined in preschool children. On each trial, a concrete or abstract word was delivered binaurally (part 1: post-auditory visualization, followed by a four-picture array (a target plus three distractors (part 2: matching visualization. Children were to select the picture matching the word they heard in part 1. Event-Related Potentials (ERPs locked to each stimulus presentation and task interval were averaged over sets of trials of increasing word abstractness. ERP time-course during both parts of the task showed that early activity (i.e. < 300 ms was predominant in response to concrete words, while activity in response to abstract words became evident only at intermediate (i.e. 300-699 ms and late (i.e. 700-1000 ms ERP intervals. Specifically, ERP topography showed that while early activity during post-auditory visualization was linked to left temporo-parietal areas for concrete words, early activity during matching visualization occurred mostly in occipito-parietal areas for concrete words, but more anteriorly in centro-parietal areas for abstract words. In intermediate ERPs, post-auditory visualization coincided with parieto-occipital and parieto-frontal activity in response to both concrete and abstract words, while in matching visualization a parieto-central activity was common to both types of words. In the late ERPs for both types of words, the post-auditory visualization involved right-hemispheric activity following a post-anterior pathway sequence: occipital, parietal and temporal areas; conversely, matching visualization involved left-hemispheric activity following an ant-posterior pathway sequence: frontal, temporal, parietal and occipital areas. These results suggest that, similarly for concrete and abstract words, meaning in young children depends on variably complex visualization processes integrating visuo-auditory experiences and supramodal embodying

Decoding task-based attentional modulation during face categorization.

Science.gov (United States)

Chiu, Yu-Chin; Esterman, Michael; Han, Yuefeng; Rosen, Heather; Yantis, Steven

2011-05-01

Attention is a neurocognitive mechanism that selects task-relevant sensory or mnemonic information to achieve current behavioral goals. Attentional modulation of cortical activity has been observed when attention is directed to specific locations, features, or objects. However, little is known about how high-level categorization task set modulates perceptual representations. In the current study, observers categorized faces by gender (male vs. female) or race (Asian vs. White). Each face was perceptually ambiguous in both dimensions, such that categorization of one dimension demanded selective attention to task-relevant information within the face. We used multivoxel pattern classification to show that task-specific modulations evoke reliably distinct spatial patterns of activity within three face-selective cortical regions (right fusiform face area and bilateral occipital face areas). This result suggests that patterns of activity in these regions reflect not only stimulus-specific (i.e., faces vs. houses) responses but also task-specific (i.e., race vs. gender) attentional modulation. Furthermore, exploratory whole-brain multivoxel pattern classification (using a searchlight procedure) revealed a network of dorsal fronto-parietal regions (left middle frontal gyrus and left inferior and superior parietal lobule) that also exhibit distinct patterns for the two task sets, suggesting that these regions may represent abstract goals during high-level categorization tasks.

From action to abstraction: Gesture as a mechanism of change.

Science.gov (United States)

Goldin-Meadow, Susan

2015-12-01

Piaget was a master at observing the routine behaviors children produce as they go from knowing less to knowing more about at a task, and making inferences not only about how the children understood the task at each point, but also about how they progressed from one point to the next. In this paper, I examine a routine behavior that Piaget overlooked-the spontaneous gestures speakers produce as they explain their solutions to a problem. These gestures are not mere hand waving. They reflect ideas that the speaker has about the problem, often ideas that are not found in that speaker's talk. But gesture can do more than reflect ideas-it can also change them. In this sense, gesture behaves like any other action; both gesture and action on objects facilitate learning problems on which training was given. However, only gesture promotes transferring the knowledge gained to problems that require generalization. Gesture is, in fact, a special kind of action in that it represents the world rather than directly manipulating the world (gesture does not move objects around). The mechanisms by which gesture and action promote learning may therefore differ-gesture is able to highlight components of an action that promote abstract learning while leaving out details that could tie learning to a specific context. Because it is both an action and a representation, gesture can serve as a bridge between the two and thus be a powerful tool for learning abstract ideas.

Method of synthesis of abstract images with high self-similarity

Science.gov (United States)

Matveev, Nikolay V.; Shcheglov, Sergey A.; Romanova, Galina E.; Koneva, Ð.¢atiana A.

2017-06-01

Abstract images with high self-similarity could be used for drug-free stress therapy. This based on the fact that a complex visual environment has a high affective appraisal. To create such an image we can use the setup based on the three laser sources of small power and different colors (Red, Green, Blue), the image is the pattern resulting from the reflecting and refracting by the complicated form object placed into the laser ray paths. The images were obtained experimentally which showed the good therapy effect. However, to find and to choose the object which gives needed image structure is very difficult and requires many trials. The goal of the work is to develop a method and a procedure of finding the object form which if placed into the ray paths can provide the necessary structure of the image In fact the task means obtaining the necessary irradiance distribution on the given surface. Traditionally such problems are solved using the non-imaging optics methods. In the given case this task is very complicated because of the complicated structure of the illuminance distribution and its high non-linearity. Alternative way is to use the projected image of a mask with a given structure. We consider both ways and discuss how they can help to speed up the synthesis procedure for the given abstract image of the high self-similarity for the setups of drug-free therapy.

Kinetic asymmetries between forward and drop jump landing tasks

Directory of Open Access Journals (Sweden)

Morgana Alves de Britto

2015-12-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n6p661   Landing asymmetry is a risk factor for knee anterior cruciate ligament injury. The aim of this study was to identify kinetic asymmetries in healthy recreational athletes performing different jump-landing techniques. Twelve recreational athletes engaged in regular training underwent kinetic evaluation using two 3D force plates and were analyzed for: (a three-dimensional peak forces, (b time to peak vertical force, and (c initial phase asymmetries. All data were collected during performance of unilateral and bilateral trials of forward and drop jump tasks. Forward jump-landing tasks elicited greater kinetic asymmetry than drop-landing tasks. Regardless of jump-landing technique, the preferred leg experienced higher forces than the non-preferred leg. The initial landing phase showed more kinetic asymmetries than the later phase when peak vertical forces occur. It was concluded that when screening athletes for kinetic asymmetries that may predispose them to injury, forward jump-landing tasks and the early landing phase might show more kinetic asymmetries than drop jump-landing tasks and the late landing phase, respectively.

A study investigating the acute dose-response effects of 13 mg and 17 mg Delta 9- tetrahydrocannabinol on cognitive-motor skills, subjective and autonomic measures in regular users of marijuana.

Science.gov (United States)

Weinstein, A; Brickner, O; Lerman, H; Greemland, M; Bloch, M; Lester, H; Chisin, R; Sarne, Y; Mechoulam, R; Bar-Hamburger, R; Freedman, N; Even-Sapir, E

2008-06-01

Heavy use of marijuana is claimed to damage critical skills related to short-term memory, visual scanning and attention. Motor skills and driving safety may be compromised by the acute effects of marijuana. The aim of this study was to investigate the acute effects of 13 mg and 17 mg Delta 9-tetrahydrocannabinol (THC) on skills important for coordinated movement and driving and on subjective and autonomic measures in regular users of marijuana. Fourteen regular users of marijuana were enrolled. Each subject was tested on two separate days. On each test day, subjects smoked two low-nicotine cigarettes, one with and the other without THC. Seventeen mg THC was included in the cigarette on one test day and 13 mg on the other day. The sequence of cigarette types was unknown to the subject. During smoking, heart rate and blood pressure were monitored, and the subjects performed a virtual reality maze task requiring attention and motor coordination, followed by 3 other cognitive tasks (Wisconsin Card Sorting Test (WCST), a "gambling" task and estimation of time and distance from an approaching car). After smoking a cigarette with 17 mg THC, regular marijuana users hit the walls more often on the virtual maze task than after smoking cigarettes without THC; this effect was not seen in patients after they smoked cigarettes with 13 mg THC. Performance in the WCST was affected with 17 mg THC and to a lesser extent with the use of 13 mg THC. Decision making in the gambling task was affected after smoking cigarettes with 17 mg THC, but not with 13 m THC. Smoking cigarettes with 13 and 17 mg THC increased subjective ratings of pleasure and satisfaction, drug "effect" and drug "high". These findings imply that smoking of 17 mg THC results in impairment of cognitive-motor skills that could be important for coordinated movement and driving, whereas the lower dose of 13 mg THC appears to cause less impairment of such skills in regular users of marijuana.

Higher derivative regularization and chiral anomaly

International Nuclear Information System (INIS)

Nagahama, Yoshinori.

1985-02-01

A higher derivative regularization which automatically leads to the consistent chiral anomaly is analyzed in detail. It explicitly breaks all the local gauge symmetry but preserves global chiral symmetry and leads to the chirally symmetric consistent anomaly. This regularization thus clarifies the physics content contained in the consistent anomaly. We also briefly comment on the application of this higher derivative regularization to massless QED. (author)

Delay discounting as a function of intrinsic/extrinsic religiousness, religious fundamentalism, and regular church attendance.

Science.gov (United States)

Weatherly, Jeffrey N; Plumm, Karyn M

2012-01-01

Delay discounting occurs when the subjective value of an outcome decreases because its delivery is delayed. Previous research has suggested that the rate at which some, but not all, outcomes are discounted varies as a function of regular church attendance. In the present study, 509 participants completed measures of intrinsic religiousness, extrinsic religiousness, religious fundamentalism, and whether they regularly attended church services. They then completed a delay-discounting task involving five outcomes. Although religiousness was not a significant predictor of discounting for all outcomes, participants scoring high in intrinsic religiousness tended to display less delay discounting than participants scoring low. Likewise, participants scoring high in religious fundamentalism tended to display more delay discounting than participants scoring low. These results partially replicate previous ones in showing that the process of discounting may vary as a function of religiousness. The results also provide some direction for those interested in altering how individuals discount.

A Hybrid Task Graph Scheduler for High Performance Image Processing Workflows.

Science.gov (United States)

Blattner, Timothy; Keyrouz, Walid; Bhattacharyya, Shuvra S; Halem, Milton; Brady, Mary

2017-12-01

Designing applications for scalability is key to improving their performance in hybrid and cluster computing. Scheduling code to utilize parallelism is difficult, particularly when dealing with data dependencies, memory management, data motion, and processor occupancy. The Hybrid Task Graph Scheduler (HTGS) improves programmer productivity when implementing hybrid workflows for multi-core and multi-GPU systems. The Hybrid Task Graph Scheduler (HTGS) is an abstract execution model, framework, and API that increases programmer productivity when implementing hybrid workflows for such systems. HTGS manages dependencies between tasks, represents CPU and GPU memories independently, overlaps computations with disk I/O and memory transfers, keeps multiple GPUs occupied, and uses all available compute resources. Through these abstractions, data motion and memory are explicit; this makes data locality decisions more accessible. To demonstrate the HTGS application program interface (API), we present implementations of two example algorithms: (1) a matrix multiplication that shows how easily task graphs can be used; and (2) a hybrid implementation of microscopy image stitching that reduces code size by ≈ 43% compared to a manually coded hybrid workflow implementation and showcases the minimal overhead of task graphs in HTGS. Both of the HTGS-based implementations show good performance. In image stitching the HTGS implementation achieves similar performance to the hybrid workflow implementation. Matrix multiplication with HTGS achieves 1.3× and 1.8× speedup over the multi-threaded OpenBLAS library for 16k × 16k and 32k × 32k size matrices, respectively.

An Exploratory Study into Perceived Task Complexity, Topic Specificity and Usefulness for Integrated Search

DEFF Research Database (Denmark)

Ingwersen, Peter; Lioma, Christina; Larsen, Birger

2012-01-01

We investigate the relations between user perceptions of work task complexity, topic specificity, and usefulness of retrieved results. 23 academic researchers submitted detailed descriptions of 65 real-life work tasks in the physics domain, and assessed documents retrieved from an integrated...... collection consisting of full text research articles in PDF, abstracts, and bibliographic records [6]. Bibliographic records were found to be more precise than full text PDFs, regardless of task complexity and topic specificity. PDFs were found to be more useful. Overall, for higher task complexity and topic...

75 FR 53966 - Regular Meeting

Science.gov (United States)

2010-09-02

... FARM CREDIT SYSTEM INSURANCE CORPORATION Regular Meeting AGENCY: Farm Credit System Insurance Corporation Board. SUMMARY: Notice is hereby given of the regular meeting of the Farm Credit System Insurance Corporation Board (Board). DATE AND TIME: The meeting of the Board will be held at the offices of the Farm...

Characterizing and Mitigating Work Time Inflation in Task Parallel Programs

Directory of Open Access Journals (Sweden)

Stephen L. Olivier

2013-01-01

Full Text Available Task parallelism raises the level of abstraction in shared memory parallel programming to simplify the development of complex applications. However, task parallel applications can exhibit poor performance due to thread idleness, scheduling overheads, and work time inflation – additional time spent by threads in a multithreaded computation beyond the time required to perform the same work in a sequential computation. We identify the contributions of each factor to lost efficiency in various task parallel OpenMP applications and diagnose the causes of work time inflation in those applications. Increased data access latency can cause significant work time inflation in NUMA systems. Our locality framework for task parallel OpenMP programs mitigates this cause of work time inflation. Our extensions to the Qthreads library demonstrate that locality-aware scheduling can improve performance up to 3X compared to the Intel OpenMP task scheduler.

Does the modified Stroop effect exist in PTSD? Evidence from dissertation abstracts and the peer reviewed literature

OpenAIRE

Kimble, Matthew O.; Frueh, B. Christopher; Marks, Libby

2009-01-01

The modified Stroop effect (MSE), in which participants show delayed color naming to trauma specific words is one of the most widely cited findings in the literature pertaining to cognitive bias in posttraumatic stress disorder (PTSD). The current study used a novel approach (Dissertation Abstract Review; DAR) to review the presence of the MSE in dissertation abstracts. A review of dissertations that used the modified Stroop task in a PTSD sample revealed that only 8% of the studies found del...

Work and family life of childrearing women workers in Japan: comparison of non-regular employees with short working hours, non-regular employees with long working hours, and regular employees.

Science.gov (United States)

Seto, Masako; Morimoto, Kanehisa; Maruyama, Soichiro

2006-05-01

This study assessed the working and family life characteristics, and the degree of domestic and work strain of female workers with different employment statuses and weekly working hours who are rearing children. Participants were the mothers of preschoolers in a large Japanese city. We classified the women into three groups according to the hours they worked and their employment conditions. The three groups were: non-regular employees working less than 30 h a week (n=136); non-regular employees working 30 h or more per week (n=141); and regular employees working 30 h or more a week (n=184). We compared among the groups the subjective values of work, financial difficulties, childcare and housework burdens, psychological effects, and strains such as work and family strain, work-family conflict, and work dissatisfaction. Regular employees were more likely to report job pressures and inflexible work schedules and to experience more strain related to work and family than non-regular employees. Non-regular employees were more likely to be facing financial difficulties. In particular, non-regular employees working longer hours tended to encounter socioeconomic difficulties and often lacked support from family and friends. Female workers with children may have different social backgrounds and different stressors according to their working hours and work status.

Does language help regularity learning? The influence of verbalizations on implicit sequential regularity learning and the emergence of explicit knowledge in children, younger and older adults.

Science.gov (United States)

Ferdinand, Nicola K; Kray, Jutta

2017-03-01

This study aimed at investigating the ability to learn regularities across the life span and examine whether this learning process can be supported or hampered by verbalizations. For this purpose, children (aged 8-10 years) and younger (aged 19-30 years) and older (aged 70-80 years) adults took part in a sequence learning experiment. We found that verbalizing sequence-congruent information during learning is a powerful tool to generate explicit knowledge and it is especially helpful for younger adults. Although recent research suggests that implicit learning can be influenced by directing the participants' attention to relevant aspects of the task, verbalizations had a much weaker influence on implicit than explicit learning. Our results show that verbalizing during learning slows down reaction times (RTs) but does not influence the amount of implicit learning. Especially older adults were not able to overcome the cost of the dual-task situation. Younger adults, in contrast, show an initial dual-tasking cost that, in the case of a helpful verbalization, is overcome with practice and turns into a RT and learning benefit. However, when the verbalization is omitted this benefit is lost, that is, better implicit learning seems to be confined to situations in which the supporting verbalization is maintained. Additionally, we did not find reliable age differences in implicit learning in the no verbalization groups, which speaks in favor of age-invariant models of implicit learning across the life span. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Incremental projection approach of regularization for inverse problems

Energy Technology Data Exchange (ETDEWEB)

Souopgui, Innocent, E-mail: innocent.souopgui@usm.edu [The University of Southern Mississippi, Department of Marine Science (United States); Ngodock, Hans E., E-mail: hans.ngodock@nrlssc.navy.mil [Naval Research Laboratory (United States); Vidard, Arthur, E-mail: arthur.vidard@imag.fr; Le Dimet, François-Xavier, E-mail: ledimet@imag.fr [Laboratoire Jean Kuntzmann (France)

2016-10-15

This paper presents an alternative approach to the regularized least squares solution of ill-posed inverse problems. Instead of solving a minimization problem with an objective function composed of a data term and a regularization term, the regularization information is used to define a projection onto a convex subspace of regularized candidate solutions. The objective function is modified to include the projection of each iterate in the place of the regularization. Numerical experiments based on the problem of motion estimation for geophysical fluid images, show the improvement of the proposed method compared with regularization methods. For the presented test case, the incremental projection method uses 7 times less computation time than the regularization method, to reach the same error target. Moreover, at convergence, the incremental projection is two order of magnitude more accurate than the regularization method.

Two Simon tasks with different sources of conflict: an ERP study of motion- and location-based compatibility effects.

Science.gov (United States)

Galashan, Daniela; Wittfoth, Matthias; Fehr, Thorsten; Herrmann, Manfred

2008-07-01

Behavioral and electrophysiological correlates of two Simon tasks were examined using comparable stimuli but different task-irrelevant and conflict-inducing stimulus features. Whereas target shape was always the task-relevant stimulus attribute, either target location (location-based task) or motion direction within the target stimuli (motion-based task) was used as a source of conflict. Data from ten healthy participants who performed both tasks are presented. In the motion-based task the incompatible condition showed smaller P300 amplitudes at Pz than the compatible condition and the location-based task yielded a trend towards a reduced P300 amplitude in the incompatible condition. For both tasks, no P300 latency differences between the conditions were found at Pz. The results suggest that the motion-based task elicits behavioral and electrophysiological effects comparable with regular Simon tasks. As all stimuli in the motion-based Simon task were presented centrally the present data strongly argue against the attention-shifting account as an explanatory approach.

Geometric regularizations and dual conifold transitions

International Nuclear Information System (INIS)

Landsteiner, Karl; Lazaroiu, Calin I.

2003-01-01

We consider a geometric regularization for the class of conifold transitions relating D-brane systems on noncompact Calabi-Yau spaces to certain flux backgrounds. This regularization respects the SL(2,Z) invariance of the flux superpotential, and allows for computation of the relevant periods through the method of Picard-Fuchs equations. The regularized geometry is a noncompact Calabi-Yau which can be viewed as a monodromic fibration, with the nontrivial monodromy being induced by the regulator. It reduces to the original, non-monodromic background when the regulator is removed. Using this regularization, we discuss the simple case of the local conifold, and show how the relevant field-theoretic information can be extracted in this approach. (author)

Adaptive regularization

DEFF Research Database (Denmark)

Hansen, Lars Kai; Rasmussen, Carl Edward; Svarer, C.

1994-01-01

Regularization, e.g., in the form of weight decay, is important for training and optimization of neural network architectures. In this work the authors provide a tool based on asymptotic sampling theory, for iterative estimation of weight decay parameters. The basic idea is to do a gradient desce...

Regularizing portfolio optimization

International Nuclear Information System (INIS)

Still, Susanne; Kondor, Imre

2010-01-01

The optimization of large portfolios displays an inherent instability due to estimation error. This poses a fundamental problem, because solutions that are not stable under sample fluctuations may look optimal for a given sample, but are, in effect, very far from optimal with respect to the average risk. In this paper, we approach the problem from the point of view of statistical learning theory. The occurrence of the instability is intimately related to over-fitting, which can be avoided using known regularization methods. We show how regularized portfolio optimization with the expected shortfall as a risk measure is related to support vector regression. The budget constraint dictates a modification. We present the resulting optimization problem and discuss the solution. The L2 norm of the weight vector is used as a regularizer, which corresponds to a diversification 'pressure'. This means that diversification, besides counteracting downward fluctuations in some assets by upward fluctuations in others, is also crucial because it improves the stability of the solution. The approach we provide here allows for the simultaneous treatment of optimization and diversification in one framework that enables the investor to trade off between the two, depending on the size of the available dataset.

Regularizing portfolio optimization

Science.gov (United States)

Still, Susanne; Kondor, Imre

2010-07-01

The optimization of large portfolios displays an inherent instability due to estimation error. This poses a fundamental problem, because solutions that are not stable under sample fluctuations may look optimal for a given sample, but are, in effect, very far from optimal with respect to the average risk. In this paper, we approach the problem from the point of view of statistical learning theory. The occurrence of the instability is intimately related to over-fitting, which can be avoided using known regularization methods. We show how regularized portfolio optimization with the expected shortfall as a risk measure is related to support vector regression. The budget constraint dictates a modification. We present the resulting optimization problem and discuss the solution. The L2 norm of the weight vector is used as a regularizer, which corresponds to a diversification 'pressure'. This means that diversification, besides counteracting downward fluctuations in some assets by upward fluctuations in others, is also crucial because it improves the stability of the solution. The approach we provide here allows for the simultaneous treatment of optimization and diversification in one framework that enables the investor to trade off between the two, depending on the size of the available dataset.

Seventh regular meeting of the International Working Group on Reliability of Reactor Pressure Components, Vienna, 3-5 September 1985

International Nuclear Information System (INIS)

1986-07-01

The seventh regular meeting of the IAEA International Working Group on Reliability of Reactor Pressure Components was held at the Agency's Headquarters in Vienna from 3 to 5 September 1985. The representatives of Member States and of the Commission of the European Communities reported the status of the research programmes in this field (12 presentations). A separate abstract was prepared for each of the presentations

Functional Task Test: 3. Skeletal Muscle Performance Adaptations to Space Flight

Science.gov (United States)

Ryder, Jeffrey W.; Wickwire, P. J.; Buxton, R. E.; Bloomberg, J. J.; Ploutz-Snyder, L.

2011-01-01

The functional task test is a multi-disciplinary study investigating how space-flight induced changes to physiological systems impacts functional task performance. Impairment of neuromuscular function would be expected to negatively affect functional performance of crewmembers following exposure to microgravity. This presentation reports the results for muscle performance testing in crewmembers. Functional task performance will be presented in the abstract "Functional Task Test 1: sensory motor adaptations associated with postflight alternations in astronaut functional task performance." METHODS: Muscle performance measures were obtained in crewmembers before and after short-duration space flight aboard the Space Shuttle and long-duration International Space Station (ISS) missions. The battery of muscle performance tests included leg press and bench press measures of isometric force, isotonic power and total work. Knee extension was used for the measurement of central activation and maximal isometric force. Upper and lower body force steadiness control were measured on the bench press and knee extension machine, respectively. Tests were implemented 60 and 30 days before launch, on landing day (Shuttle crew only), and 6, 10 and 30 days after landing. Seven Space Shuttle crew and four ISS crew have completed the muscle performance testing to date. RESULTS: Preliminary results for Space Shuttle crew reveal significant reductions in the leg press performance metrics of maximal isometric force, power and total work on R+0 (pperformance metrics were observed in returning Shuttle crew and these adaptations are likely contributors to impaired functional tasks that are ambulatory in nature (See abstract Functional Task Test: 1). Interestingly, no significant changes in central activation capacity were detected. Therefore, impairments in muscle function in response to short-duration space flight are likely myocellular rather than neuromotor in nature.

Tessellating the Sphere with Regular Polygons

Science.gov (United States)

Soto-Johnson, Hortensia; Bechthold, Dawn

2004-01-01

Tessellations in the Euclidean plane and regular polygons that tessellate the sphere are reviewed. The regular polygons that can possibly tesellate the sphere are spherical triangles, squares and pentagons.

Situated conceptualization and semantic processing: effects of emotional experience and context availability in semantic categorization and naming tasks.

Science.gov (United States)

Moffat, Michael; Siakaluk, Paul D; Sidhu, David M; Pexman, Penny M

2015-04-01

It has been proposed that much of conceptual knowledge is acquired through situated conceptualization, such that both external (e.g., agents, objects, events) and internal (e.g., emotions, introspections) environments are considered important (Barsalou, 2003). To evaluate this proposal, we characterized two dimensions by which situated conceptualization may be measured and which should have different relevance for abstract and concrete concepts; namely, emotional experience (i.e., the ease with which words evoke emotional experience; Newcombe, Campbell, Siakaluk, & Pexman, 2012) and context availability (i.e., the ease with which words evoke contexts in which their referents may appear; Schwanenflugel & Shoben, 1983). We examined the effects of these two dimensions on abstract and concrete word processing in verbal semantic categorization (VSCT) and naming tasks. In the VSCT, emotional experience facilitated processing of abstract words but inhibited processing of concrete words, whereas context availability facilitated processing of both types of words. In the naming task in which abstract words and concrete words were not blocked by emotional experience, context availability facilitated responding to only the abstract words. In the naming task in which abstract words and concrete words were blocked by emotional experience, emotional experience facilitated responding to only the abstract words, whereas context availability facilitated responding to only the concrete words. These results were observed even with several lexical (e.g., frequency, age of acquisition) and semantic (e.g., concreteness, arousal, valence) variables included in the analyses. As such, the present research suggests that emotional experience and context availability tap into different aspects of situated conceptualization and make unique contributions to the representation and processing of abstract and concrete concepts.

Effects of syntactic structure in the memory of concrete and abstract Chinese sentences.

Science.gov (United States)

Ho, C S; Chen, H C

1993-09-01

Smith (1981) found that concrete English sentences were better recognized than abstract sentences and that this concreteness effect was potent only when the concrete sentence was also affirmative but the effect switched to an opposite end when the concrete sentence was negative. These results were partially replicated in Experiment 1 by using materials from a very different language (i.e., Chinese): concrete-affirmative sentences were better remembered than concrete-negative and abstract sentences, but no reliable difference was found between the latter two types. In Experiment 2, the task was modified by using a visual presentation instead of an oral one as in Experiment 1. Both concrete-affirmative and concrete-negative sentences were better memorized then abstract ones in Experiment 2. The findings in the two experiments are explained by a combination of the dual-coding model and Marschark's (1985) item-specific and relational processing. The differential effects of experience with different language systems on processing verbal materials in memory are also discussed.

Word type effects in false recall: concrete, abstract, and emotion word critical lures.

Science.gov (United States)

Bauer, Lisa M; Olheiser, Erik L; Altarriba, Jeanette; Landi, Nicole

2009-01-01

Previous research has demonstrated that definable qualities of verbal stimuli have implications for memory. For example, the distinction between concrete and abstract words has led to the finding that concrete words have an advantage in memory tasks (i.e., the concreteness effect). However, other word types, such as words that label specific human emotions, may also affect memory processes. This study examined the effects of word type on the production of false memories by using a list-learning false memory paradigm. Participants heard lists of words that were highly associated to nonpresented concrete, abstract, or emotion words (i.e., the critical lures) and then engaged in list recall. Emotion word critical lures were falsely recalled at a significantly higher rate (with the effect carried by the positively valenced critical lures) than concrete and abstract critical lures. These findings suggest that the word type variable has implications for our understanding of the mechanisms that underlie recall and false recall.

Affordances and synchronization in collective creative construction tasks

DEFF Research Database (Denmark)

Tylén, Kristian; Fusaroli, Riccardo

What does it mean to cooperate? How do we share meanings and actions in order to reach a common goal? In this paper we explore the relation between cooperative coordination and heart rate. We argue that in cooperative contexts participants synchronize their heart rhythms according to two factors......: the affordances of the task at hand and the gradual consolidation of collaborative practices. Six groups of participants were instructed to construct LEGO models of six abstract notions (“responsibility”, “knowledge”, “justice” etc.), both individually and in groups. We combine video analysis and heart rate...... measurements and employ recurrence analysis techniques to quantify the mutual adaptability of heart rates among the participants in the different tasks. We show that during individual tasks individual heart rates synchronize both within and between groups (but not with controls) plausibly due...

Accretion onto some well-known regular black holes

International Nuclear Information System (INIS)

Jawad, Abdul; Shahzad, M.U.

2016-01-01

In this work, we discuss the accretion onto static spherically symmetric regular black holes for specific choices of the equation of state parameter. The underlying regular black holes are charged regular black holes using the Fermi-Dirac distribution, logistic distribution, nonlinear electrodynamics, respectively, and Kehagias-Sftesos asymptotically flat regular black holes. We obtain the critical radius, critical speed, and squared sound speed during the accretion process near the regular black holes. We also study the behavior of radial velocity, energy density, and the rate of change of the mass for each of the regular black holes. (orig.)

Accretion onto some well-known regular black holes

Energy Technology Data Exchange (ETDEWEB)

Jawad, Abdul; Shahzad, M.U. [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan)

2016-03-15

In this work, we discuss the accretion onto static spherically symmetric regular black holes for specific choices of the equation of state parameter. The underlying regular black holes are charged regular black holes using the Fermi-Dirac distribution, logistic distribution, nonlinear electrodynamics, respectively, and Kehagias-Sftesos asymptotically flat regular black holes. We obtain the critical radius, critical speed, and squared sound speed during the accretion process near the regular black holes. We also study the behavior of radial velocity, energy density, and the rate of change of the mass for each of the regular black holes. (orig.)

Accretion onto some well-known regular black holes

Science.gov (United States)

Jawad, Abdul; Shahzad, M. Umair

2016-03-01

In this work, we discuss the accretion onto static spherically symmetric regular black holes for specific choices of the equation of state parameter. The underlying regular black holes are charged regular black holes using the Fermi-Dirac distribution, logistic distribution, nonlinear electrodynamics, respectively, and Kehagias-Sftesos asymptotically flat regular black holes. We obtain the critical radius, critical speed, and squared sound speed during the accretion process near the regular black holes. We also study the behavior of radial velocity, energy density, and the rate of change of the mass for each of the regular black holes.

Processing emotion from abstract art in frontotemporal lobar degeneration.

Science.gov (United States)

Cohen, Miriam H; Carton, Amelia M; Hardy, Christopher J; Golden, Hannah L; Clark, Camilla N; Fletcher, Phillip D; Jaisin, Kankamol; Marshall, Charles R; Henley, Susie M D; Rohrer, Jonathan D; Crutch, Sebastian J; Warren, Jason D

2016-01-29

art may signal emotions independently of a biological or social carrier: it might therefore constitute a test case for defining brain mechanisms of generic emotion decoding and the impact of disease states on those mechanisms. This is potentially of particular relevance to diseases in the frontotemporal lobar degeneration (FTLD) spectrum. These diseases are often led by emotional impairment despite retained or enhanced artistic interest in at least some patients. However, the processing of emotion from art has not been studied systematically in FTLD. Here we addressed this issue using a novel emotional valence matching task on abstract paintings in patients representing major syndromes of FTLD (behavioural variant frontotemporal dementia, n=11; sematic variant primary progressive aphasia (svPPA), n=7; nonfluent variant primary progressive aphasia (nfvPPA), n=6) relative to healthy older individuals (n=39). Performance on art emotion valence matching was compared between groups taking account of perceptual matching performance and assessed in relation to facial emotion matching using customised control tasks. Neuroanatomical correlates of art emotion processing were assessed using voxel-based morphometry of patients' brain MR images. All patient groups had a deficit of art emotion processing relative to healthy controls; there were no significant interactions between syndromic group and emotion modality. Poorer art emotion valence matching performance was associated with reduced grey matter volume in right lateral occopitotemporal cortex in proximity to regions previously implicated in the processing of dynamic visual signals. Our findings suggest that abstract art may be a useful model system for investigating mechanisms of generic emotion decoding and aesthetic processing in neurodegenerative diseases. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Combined factors effect of menstrual cycle and background noise on visual inspection task performance: a simulation-based task.

Science.gov (United States)

Wijayanto, Titis; Tochihara, Yutaka; Wijaya, Andi R; Hermawati, Setia

2009-11-01

It is well known that women are physiologically and psychologically influenced by the menstrual cycle. In addition, the presence of background noise may affect task performance. So far, it has proven difficult to describe how the menstrual cycle and background noise affect task performance; some researchers have found an increment of performance during menstruation or during the presence of noise, others found performance deterioration, while other still have reported no dominant effect either of the menstrual cycle in performance or of the presence of noise. However, no study to date has investigated the combinational effect between the menstrual cycle and the presence of background noise in task performance. Therefore, the purpose of this study was to examine the combined factor effect of menstrual cycle and background noise on visual inspection task performance indices by Signal Detection Theory (SDT) metrics: sensitivity index (d') and response criteria index (beta). For this purpose, ten healthy female students (21.5+/-1.08 years) with a regular menstrual cycle participated in this study. A VDT-based visual inspection task was used for the experiment in 3x2 factorial designs. Two factors, menstrual phase, pre-menstruation (PMS), menstruation (M), and post-menstruation (PM) and background noise, with 80 dB(A) background noise and without noise, were analyzed as the main factors in this study. The results concluded that the sensitivity index (d') of SDT was affected in all the menstrual cycle conditions (pbackground noise (pbackground noise was found in this study. On the other hand, no significant effect was observed in the subject's tendency in visual inspection, shown by beta along the menstrual cycle and the presence of background noise. According to the response criteria for each individual subject, the presence of noise affected the tendency of some subjects in detecting the object and making decision during the visual inspection task.

Diagrammatic methods in phase-space regularization

International Nuclear Information System (INIS)

Bern, Z.; Halpern, M.B.; California Univ., Berkeley

1987-11-01

Using the scalar prototype and gauge theory as the simplest possible examples, diagrammatic methods are developed for the recently proposed phase-space form of continuum regularization. A number of one-loop and all-order applications are given, including general diagrammatic discussions of the nogrowth theorem and the uniqueness of the phase-space stochastic calculus. The approach also generates an alternate derivation of the equivalence of the large-β phase-space regularization to the more conventional coordinate-space regularization. (orig.)

Metric regularity and subdifferential calculus

International Nuclear Information System (INIS)

Ioffe, A D

2000-01-01

The theory of metric regularity is an extension of two classical results: the Lyusternik tangent space theorem and the Graves surjection theorem. Developments in non-smooth analysis in the 1980s and 1990s paved the way for a number of far-reaching extensions of these results. It was also well understood that the phenomena behind the results are of metric origin, not connected with any linear structure. At the same time it became clear that some basic hypotheses of the subdifferential calculus are closely connected with the metric regularity of certain set-valued maps. The survey is devoted to the metric theory of metric regularity and its connection with subdifferential calculus in Banach spaces

Conference on Geometric Analysis &Conference on Type Theory, Homotopy Theory and Univalent Foundations : Extended Abstracts Fall 2013

CERN Document Server

Yang, Paul; Gambino, Nicola; Kock, Joachim

2015-01-01

The two parts of the present volume contain extended conference abstracts corresponding to selected talks given by participants at the "Conference on Geometric Analysis" (thirteen abstracts) and at the "Conference on Type Theory, Homotopy Theory and Univalent Foundations" (seven abstracts), both held at the Centre de Recerca Matemàtica (CRM) in Barcelona from July 1st to 5th, 2013, and from September 23th to 27th, 2013, respectively. Most of them are brief articles, containing preliminary presentations of new results not yet published in regular research journals. The articles are the result of a direct collaboration between active researchers in the area after working in a dynamic and productive atmosphere. The first part is about Geometric Analysis and Conformal Geometry; this modern field lies at the intersection of many branches of mathematics (Riemannian, Conformal, Complex or Algebraic Geometry, Calculus of Variations, PDE's, etc) and relates directly to the physical world, since many natural phenomena...

Descriptor Learning via Supervised Manifold Regularization for Multioutput Regression.

Science.gov (United States)

Zhen, Xiantong; Yu, Mengyang; Islam, Ali; Bhaduri, Mousumi; Chan, Ian; Li, Shuo

2017-09-01

Multioutput regression has recently shown great ability to solve challenging problems in both computer vision and medical image analysis. However, due to the huge image variability and ambiguity, it is fundamentally challenging to handle the highly complex input-target relationship of multioutput regression, especially with indiscriminate high-dimensional representations. In this paper, we propose a novel supervised descriptor learning (SDL) algorithm for multioutput regression, which can establish discriminative and compact feature representations to improve the multivariate estimation performance. The SDL is formulated as generalized low-rank approximations of matrices with a supervised manifold regularization. The SDL is able to simultaneously extract discriminative features closely related to multivariate targets and remove irrelevant and redundant information by transforming raw features into a new low-dimensional space aligned to targets. The achieved discriminative while compact descriptor largely reduces the variability and ambiguity for multioutput regression, which enables more accurate and efficient multivariate estimation. We conduct extensive evaluation of the proposed SDL on both synthetic data and real-world multioutput regression tasks for both computer vision and medical image analysis. Experimental results have shown that the proposed SDL can achieve high multivariate estimation accuracy on all tasks and largely outperforms the algorithms in the state of the arts. Our method establishes a novel SDL framework for multioutput regression, which can be widely used to boost the performance in different applications.

BioNLP Shared Task--The Bacteria Track.

Science.gov (United States)

Bossy, Robert; Jourde, Julien; Manine, Alain-Pierre; Veber, Philippe; Alphonse, Erick; van de Guchte, Maarten; Bessières, Philippe; Nédellec, Claire

2012-06-26

We present the BioNLP 2011 Shared Task Bacteria Track, the first Information Extraction challenge entirely dedicated to bacteria. It includes three tasks that cover different levels of biological knowledge. The Bacteria Gene Renaming supporting task is aimed at extracting gene renaming and gene name synonymy in PubMed abstracts. The Bacteria Gene Interaction is a gene/protein interaction extraction task from individual sentences. The interactions have been categorized into ten different sub-types, thus giving a detailed account of genetic regulations at the molecular level. Finally, the Bacteria Biotopes task focuses on the localization and environment of bacteria mentioned in textbook articles. We describe the process of creation for the three corpora, including document acquisition and manual annotation, as well as the metrics used to evaluate the participants' submissions. Three teams submitted to the Bacteria Gene Renaming task; the best team achieved an F-score of 87%. For the Bacteria Gene Interaction task, the only participant's score had reached a global F-score of 77%, although the system efficiency varies significantly from one sub-type to another. Three teams submitted to the Bacteria Biotopes task with very different approaches; the best team achieved an F-score of 45%. However, the detailed study of the participating systems efficiency reveals the strengths and weaknesses of each participating system. The three tasks of the Bacteria Track offer participants a chance to address a wide range of issues in Information Extraction, including entity recognition, semantic typing and coreference resolution. We found common trends in the most efficient systems: the systematic use of syntactic dependencies and machine learning. Nevertheless, the originality of the Bacteria Biotopes task encouraged the use of interesting novel methods and techniques, such as term compositionality, scopes wider than the sentence.

Semantic size of abstract concepts: it gets emotional when you can't see it.

Science.gov (United States)

Yao, Bo; Vasiljevic, Milica; Weick, Mario; Sereno, Margaret E; O'Donnell, Patrick J; Sereno, Sara C

2013-01-01

Size is an important visuo-spatial characteristic of the physical world. In language processing, previous research has demonstrated a processing advantage for words denoting semantically "big" (e.g., jungle) versus "small" (e.g., needle) concrete objects. We investigated whether semantic size plays a role in the recognition of words expressing abstract concepts (e.g., truth). Semantically "big" and "small" concrete and abstract words were presented in a lexical decision task. Responses to "big" words, regardless of their concreteness, were faster than those to "small" words. Critically, we explored the relationship between semantic size and affective characteristics of words as well as their influence on lexical access. Although a word's semantic size was correlated with its emotional arousal, the temporal locus of arousal effects may depend on the level of concreteness. That is, arousal seemed to have an earlier (lexical) effect on abstract words, but a later (post-lexical) effect on concrete words. Our findings provide novel insights into the semantic representations of size in abstract concepts and highlight that affective attributes of words may not always index lexical access.

Temporal regularity of the environment drives time perception

OpenAIRE

van Rijn, H; Rhodes, D; Di Luca, M

2016-01-01

It’s reasonable to assume that a regularly paced sequence should be perceived as regular, but here we show that perceived regularity depends on the context in which the sequence is embedded. We presented one group of participants with perceptually regularly paced sequences, and another group of participants with mostly irregularly paced sequences (75% irregular, 25% regular). The timing of the final stimulus in each sequence could be var- ied. In one experiment, we asked whether the last stim...

Regular rehearsal helps in consolidation of long term memory.

Science.gov (United States)

Parle, Milind; Singh, Nirmal; Vasudevan, Mani

2006-01-01

Memory, one of the most complex functions of the brain comprises of multiple components such as perception, registration, consolidation, storage, retrieval and decay. The present study was undertaken to evaluate the impact of different training sessions on the retention capacity of rats. The capacity of retention of learnt task was measured using exteroceptive behavioral models such as Hexagonal swimming pool apparatus, Hebb-Williams maze and Elevated plus-maze. A total of 150 rats divided into fifteen groups were employed in the present study. The animals were subjected to different training sessions during first three days. The ability to retain the learned task was tested after single, sub-acute, acute, sub-chronic and chronic exposure to above exteroceptive memory models in separate groups of animals. The memory score of all animals was recorded after 72 h, 192 h and 432 h of their last training trial. Rats of single exposure group did not show any effect on memory. Sub-acute training group animals showed improved memory up to 72 h only, where as in acute and sub-chronic training groups this memory improvement was extended up to 192 h. The rats, which were subjected to chronic exposures showed a significant improvement in retention capacity that lasted up to a period of eighteen days. These observations suggest that repeated rehearsals at regular intervals are probably necessary for consolidation of long-term memory. It was observed that sub-acute, acute and sub-chronic exposures, improved the retrieval ability of rats but this memory improving effect was short lived. Thus, rehearsal or training plays a crucial role in enhancing one's capacity of retaining the learnt information. Key PointsThe present study underlines the importance of regular rehearsals in enhancing one's capacity of retaining the learnt information. " Sub-acute, acute & sub-chronic rehearsals result in storing of information for a limited period of time.Quick decay of information or

An inconclusive study comparing the effect of concrete and abstract descriptions of belief-inconsistent information.

Science.gov (United States)

Collins, Katherine A; Clément, Richard

2018-01-01

Linguistic bias is the differential use of linguistic abstraction (as defined by the Linguistic Category Model) to describe the same behaviour for members of different groups. Essentially, it is the tendency to use concrete language for belief-inconsistent behaviours and abstract language for belief-consistent behaviours. Having found that linguistic bias is produced without intention or awareness in many contexts, researchers argue that linguistic bias reflects, reinforces, and transmits pre-existing beliefs, thus playing a role in belief maintenance. Based on the Linguistic Category Model, this assumes that concrete descriptions reduce the impact of belief-inconsistent behaviours while abstract descriptions maximize the impact of belief-consistent behaviours. However, a key study by Geschke, Sassenberg, Ruhrmann, and Sommer [2007] found that concrete descriptions of belief-inconsistent behaviours actually had a greater impact than abstract descriptions, a finding that does not fit easily within the linguistic bias paradigm. Abstract descriptions (e.g. the elderly woman is athletic) are, by definition, more open to interpretation than concrete descriptions (e.g. the elderly woman works out regularly). It is thus possible that abstract descriptions are (1) perceived as having less evidentiary strength than concrete descriptions, and (2) understood in context (i.e. athletic for an elderly woman). In this study, the design of Geschke et al. [2007] was modified to address this possibility. We expected that the differences in the impact of concrete and abstract descriptions would be reduced or reversed, but instead we found that differences were largely absent. This study did not support the findings of Geschke et al. [2007] or the linguistic bias paradigm. We encourage further attempts to understand the strong effect of concrete descriptions for belief-inconsistent behaviour.

The uniqueness of the regularization procedure

International Nuclear Information System (INIS)

Brzezowski, S.

1981-01-01

On the grounds of the BPHZ procedure, the criteria of correct regularization in perturbation calculations of QFT are given, together with the prescription for dividing the regularized formulas into the finite and infinite parts. (author)

Proceedings of the Task 2 workshop Waste Isolation Safety Assessment Program

International Nuclear Information System (INIS)

Bradley, D.J.

1979-01-01

The reports from the workshop on waste form release rate analysis are presented. The workshop started with overview presentations on the Office of Nuclear Waste Isolation (ONWI), the Waste Isolation Safety Assessment Program (WISAP), WISAP Task 2 (Waste Form Release Rate Analysis), and WISAP Task 4 (Sorption/Desorption Analysis). Technical presentations followed in these areas: leaching studies on spent fuels, leaching studies on high-level waste glass, waste form surface science experiments, radiation effects, and leach modeling. Separate abstracts were prepared for each

Proceedings of the Task 2 workshop Waste Isolation Safety Assessment Program

Energy Technology Data Exchange (ETDEWEB)

Bradley, D.J.

1979-01-01

The reports from the workshop on waste form release rate analysis are presented. The workshop started with overview presentations on the Office of Nuclear Waste Isolation (ONWI), the Waste Isolation Safety Assessment Program (WISAP), WISAP Task 2 (Waste Form Release Rate Analysis), and WISAP Task 4 (Sorption/Desorption Analysis). Technical presentations followed in these areas: leaching studies on spent fuels, leaching studies on high-level waste glass, waste form surface science experiments, radiation effects, and leach modeling. Separate abstracts were prepared for each.

Coupling regularizes individual units in noisy populations

International Nuclear Information System (INIS)

Ly Cheng; Ermentrout, G. Bard

2010-01-01

The regularity of a noisy system can modulate in various ways. It is well known that coupling in a population can lower the variability of the entire network; the collective activity is more regular. Here, we show that diffusive (reciprocal) coupling of two simple Ornstein-Uhlenbeck (O-U) processes can regularize the individual, even when it is coupled to a noisier process. In cellular networks, the regularity of individual cells is important when a select few play a significant role. The regularizing effect of coupling surprisingly applies also to general nonlinear noisy oscillators. However, unlike with the O-U process, coupling-induced regularity is robust to different kinds of coupling. With two coupled noisy oscillators, we derive an asymptotic formula assuming weak noise and coupling for the variance of the period (i.e., spike times) that accurately captures this effect. Moreover, we find that reciprocal coupling can regularize the individual period of higher dimensional oscillators such as the Morris-Lecar and Brusselator models, even when coupled to noisier oscillators. Coupling can have a counterintuitive and beneficial effect on noisy systems. These results have implications for the role of connectivity with noisy oscillators and the modulation of variability of individual oscillators.

5 CFR 551.421 - Regular working hours.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Regular working hours. 551.421 Section... Activities § 551.421 Regular working hours. (a) Under the Act there is no requirement that a Federal employee... distinction based on whether the activity is performed by an employee during regular working hours or outside...

Regular extensions of some classes of grammars

NARCIS (Netherlands)

Nijholt, Antinus

Culik and Cohen introduced the class of LR-regular grammars, an extension of the LR(k) grammars. In this report we consider the analogous extension of the LL(k) grammers, called the LL-regular grammars. The relations of this class of grammars to other classes of grammars are shown. Every LL-regular

Neural Determinants of Task Performance during Feature-Based Attention in Human Cortex

Science.gov (United States)

Gong, Mengyuan

2018-01-01

Abstract Studies of feature-based attention have associated activity in a dorsal frontoparietal network with putative attentional priority signals. Yet, how this neural activity mediates attentional selection and whether it guides behavior are fundamental questions that require investigation. We reasoned that endogenous fluctuations in the quality of attentional priority should influence task performance. Human subjects detected a speed increment while viewing clockwise (CW) or counterclockwise (CCW) motion (baseline task) or while attending to either direction amid distracters (attention task). In an fMRI experiment, direction-specific neural pattern similarity between the baseline task and the attention task revealed a higher level of similarity for correct than incorrect trials in frontoparietal regions. Using transcranial magnetic stimulation (TMS), we disrupted posterior parietal cortex (PPC) and found a selective deficit in the attention task, but not in the baseline task, demonstrating the necessity of this cortical area during feature-based attention. These results reveal that frontoparietal areas maintain attentional priority that facilitates successful behavioral selection. PMID:29497703

Factors associated with regular consumption of obesogenic foods: National School-Based Student Health Hurvey, 2012

Directory of Open Access Journals (Sweden)

Giovana LONGO-SILVA

Full Text Available ABSTRACT Objective: To investigate the frequency of consumption of obesogenic foods among adolescents and its association with sociodemographic, family, behavioral, and environmental variables. Methods: Secondary data from the National School-Based Student Health Hurvey were analyzed from a representative sample of 9th grade Brazilian students (high school. A self-administered questionnaire, organized into thematic blocks, was used. The dependent variables were the consumption of deep fried snacks, packaged snacks, sugar candies, and soft drinks; consumption frequency for the seven days preceding the study was analyzed. Bivariate analysis was carried out to determine the empirical relationship between the regular consumption of these foods (≥3 days/week with sociodemographic, family, behavioral, and school structural variables. p-value <0.20 was used as the criterion for initial inclusion in the multivariate logistic analysis, which was conducted using the "Enter" method, and the results were expressed as adjusted odds ratios with 95% confidence interval and p<0.05 indicating a statistically significance. Results: Regular food consumption ranged from 27.17% to 65.96%. The variables female gender, mobile phone ownership, Internet access at home, tobacco use, alcohol consumption, regular physical activity, eating while watching television or studying, watching television for at least 2 hours a day, and not willing to lose weight were associated in the final logistic models of all foods analyzed. Conclusion: It was concluded that fried snacks, packaged snacks, sugar candies, and soft drinks are regularly consumed by adolescents and that such consumption was associated with the sociodemographic, family, behavioral, and school structural variables.

Regular non-twisting S-branes

International Nuclear Information System (INIS)

Obregon, Octavio; Quevedo, Hernando; Ryan, Michael P.

2004-01-01

We construct a family of time and angular dependent, regular S-brane solutions which corresponds to a simple analytical continuation of the Zipoy-Voorhees 4-dimensional vacuum spacetime. The solutions are asymptotically flat and turn out to be free of singularities without requiring a twist in space. They can be considered as the simplest non-singular generalization of the singular S0-brane solution. We analyze the properties of a representative of this family of solutions and show that it resembles to some extent the asymptotic properties of the regular Kerr S-brane. The R-symmetry corresponds, however, to the general lorentzian symmetry. Several generalizations of this regular solution are derived which include a charged S-brane and an additional dilatonic field. (author)

Programme and abstracts

International Nuclear Information System (INIS)

1975-01-01

Abstracts of 25 papers presented at the congress are given. The abstracts cover various topics including radiotherapy, radiopharmaceuticals, radioimmunoassay, health physics, radiation protection and nuclear medicine

2018 Congress Podium Abstracts

Science.gov (United States)

2018-02-21

Each abstract has been indexed according to first author. Abstracts appear as they were submitted and have not undergone editing or the Oncology Nursing Forum’s review process. Only abstracts that will be presented appear here. For Congress scheduling information, visit congress.ons.org or check the Congress guide. Data published in abstracts presented at the ONS 43rd Annual Congress are embargoed until the conclusion of the presentation. Coverage and/or distribution of an abstract, poster, or any of its supplemental material to or by the news media, any commercial entity, or individuals, including the authors of said abstract, is strictly prohibited until the embargo is lifted. Promotion of general topics and speakers is encouraged within these guidelines.

Investigating the functional neuroanatomy of concrete and abstract word processing through direct electric stimulation (DES) during awake surgery.

Science.gov (United States)

Orena, E F; Caldiroli, D; Acerbi, F; Barazzetta, I; Papagno, C

2018-06-05

Neuropsychological, neuroimaging and electrophysiological studies demonstrate that abstract and concrete word processing relies not only on the activity of a common bilateral network but also on dedicated networks. The neuropsychological literature has shown that a selective sparing of abstract relative to concrete words can be documented in lesions of the left anterior temporal regions. We investigated concrete and abstract word processing in 10 patients undergoing direct electrical stimulation (DES) for brain mapping during awake surgery in the left hemisphere. A lexical decision and a concreteness judgment task were added to the neuropsychological assessment during intra-operative monitoring. On the concreteness judgment, DES delivered over the inferior frontal gyrus significantly decreased abstract word accuracy while accuracy for concrete words decreased when the anterior temporal cortex was stimulated. These results are consistent with a lexical-semantic model that distinguishes between concrete and abstract words related to different neural substrates in the left hemisphere.

Spatial Programming for Industrial Robots through Task Demonstration

Directory of Open Access Journals (Sweden)

Jens Lambrecht

2013-05-01

Full Text Available Abstract We present an intuitive system for the programming of industrial robots using markerless gesture recognition and mobile augmented reality in terms of programming by demonstration. The approach covers gesture-based task definition and adaption by human demonstration, as well as task evaluation through augmented reality. A 3D motion tracking system and a handheld device establish the basis for the presented spatial programming system. In this publication, we present a prototype toward the programming of an assembly sequence consisting of several pick-and-place tasks. A scene reconstruction provides pose estimation of known objects with the help of the 2D camera of the handheld. Therefore, the programmer is able to define the program through natural bare-hand manipulation of these objects with the help of direct visual feedback in the augmented reality application. The program can be adapted by gestures and transmitted subsequently to an arbitrary industrial robot controller using a unified interface. Finally, we discuss an application of the presented spatial programming approach toward robot-based welding tasks.

Spontaneous generalization of abstract multimodal patterns in young domestic chicks.

Science.gov (United States)

Versace, Elisabetta; Spierings, Michelle J; Caffini, Matteo; Ten Cate, Carel; Vallortigara, Giorgio

2017-05-01

From the early stages of life, learning the regularities associated with specific objects is crucial for making sense of experiences. Through filial imprinting, young precocial birds quickly learn the features of their social partners by mere exposure. It is not clear though to what extent chicks can extract abstract patterns of the visual and acoustic stimuli present in the imprinting object, and how they combine them. To investigate this issue, we exposed chicks (Gallus gallus) to three days of visual and acoustic imprinting, using either patterns with two identical items or patterns with two different items, presented visually, acoustically or in both modalities. Next, chicks were given a choice between the familiar and the unfamiliar pattern, present in either the multimodal, visual or acoustic modality. The responses to the novel stimuli were affected by their imprinting experience, and the effect was stronger for chicks imprinted with multimodal patterns than for the other groups. Interestingly, males and females adopted a different strategy, with males more attracted by unfamiliar patterns and females more attracted by familiar patterns. Our data show that chicks can generalize abstract patterns by mere exposure through filial imprinting and that multimodal stimulation is more effective than unimodal stimulation for pattern learning.

Near-Regular Structure Discovery Using Linear Programming

KAUST Repository

Huang, Qixing

2014-06-02

Near-regular structures are common in manmade and natural objects. Algorithmic detection of such regularity greatly facilitates our understanding of shape structures, leads to compact encoding of input geometries, and enables efficient generation and manipulation of complex patterns on both acquired and synthesized objects. Such regularity manifests itself both in the repetition of certain geometric elements, as well as in the structured arrangement of the elements. We cast the regularity detection problem as an optimization and efficiently solve it using linear programming techniques. Our optimization has a discrete aspect, that is, the connectivity relationships among the elements, as well as a continuous aspect, namely the locations of the elements of interest. Both these aspects are captured by our near-regular structure extraction framework, which alternates between discrete and continuous optimizations. We demonstrate the effectiveness of our framework on a variety of problems including near-regular structure extraction, structure-preserving pattern manipulation, and markerless correspondence detection. Robustness results with respect to geometric and topological noise are presented on synthesized, real-world, and also benchmark datasets. © 2014 ACM.

Rheem: Enabling Multi-Platform Task Execution

KAUST Repository

Agrawal, Divy; Kruse, Sebastian; Ouzzani, Mourad; Papotti, Paolo; Quiane-Ruiz, Jorge-Arnulfo; Tang, Nan; Zaki, Mohammed J.; Ba, Lamine; Berti-Equille, Laure; Chawla, Sanjay; Elmagarmid, Ahmed; Hammady, Hossam; Idris, Yasser; Kaoudi, Zoi; Khayyat, Zuhair

2016-01-01

Many emerging applications, from domains such as healthcare and oil & gas, require several data processing systems for complex analytics. This demo paper showcases Rheem, a framework that provides multi-platform task execution for such applications. It features a three-layer data processing abstraction and a new query optimization approach for multi-platform settings. We will demonstrate the strengths of Rheem by using real-world scenarios from three different applications, namely, machine learning, data cleaning, and data fusion. © 2016 ACM.

Rheem: Enabling Multi-Platform Task Execution

KAUST Repository

Agrawal, Divy

2016-06-16

Many emerging applications, from domains such as healthcare and oil & gas, require several data processing systems for complex analytics. This demo paper showcases Rheem, a framework that provides multi-platform task execution for such applications. It features a three-layer data processing abstraction and a new query optimization approach for multi-platform settings. We will demonstrate the strengths of Rheem by using real-world scenarios from three different applications, namely, machine learning, data cleaning, and data fusion. © 2016 ACM.

Tetravalent one-regular graphs of order 4p2

DEFF Research Database (Denmark)

Feng, Yan-Quan; Kutnar, Klavdija; Marusic, Dragan

2014-01-01

A graph is one-regular if its automorphism group acts regularly on the set of its arcs. In this paper tetravalent one-regular graphs of order 4p2, where p is a prime, are classified.......A graph is one-regular if its automorphism group acts regularly on the set of its arcs. In this paper tetravalent one-regular graphs of order 4p2, where p is a prime, are classified....

Robust visual tracking via multi-task sparse learning

KAUST Repository

Zhang, Tianzhu

2012-06-01

In this paper, we formulate object tracking in a particle filter framework as a multi-task sparse learning problem, which we denote as Multi-Task Tracking (MTT). Since we model particles as linear combinations of dictionary templates that are updated dynamically, learning the representation of each particle is considered a single task in MTT. By employing popular sparsity-inducing p, q mixed norms (p D; 1), we regularize the representation problem to enforce joint sparsity and learn the particle representations together. As compared to previous methods that handle particles independently, our results demonstrate that mining the interdependencies between particles improves tracking performance and overall computational complexity. Interestingly, we show that the popular L 1 tracker [15] is a special case of our MTT formulation (denoted as the L 11 tracker) when p q 1. The learning problem can be efficiently solved using an Accelerated Proximal Gradient (APG) method that yields a sequence of closed form updates. As such, MTT is computationally attractive. We test our proposed approach on challenging sequences involving heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that MTT methods consistently outperform state-of-the-art trackers. © 2012 IEEE.

Regularization and error assignment to unfolded distributions

CERN Document Server

Zech, Gunter

2011-01-01

The commonly used approach to present unfolded data only in graphical formwith the diagonal error depending on the regularization strength is unsatisfac-tory. It does not permit the adjustment of parameters of theories, the exclusionof theories that are admitted by the observed data and does not allow the com-bination of data from different experiments. We propose fixing the regulariza-tion strength by a p-value criterion, indicating the experimental uncertaintiesindependent of the regularization and publishing the unfolded data in additionwithout regularization. These considerations are illustrated with three differentunfolding and smoothing approaches applied to a toy example.

2018 Congress Poster Abstracts

Science.gov (United States)

2018-02-21

Each abstract has been indexed according to the first author. Abstracts appear as they were submitted and have not undergone editing or the Oncology Nursing Forum’s review process. Only abstracts that will be presented appear here. Poster numbers are subject to change. For updated poster numbers, visit congress.ons.org or check the Congress guide. Data published in abstracts presented at the ONS 43rd Annual Congress are embargoed until the conclusion of the presentation. Coverage and/or distribution of an abstract, poster, or any of its supplemental material to or by the news media, any commercial entity, or individuals, including the authors of said abstract, is strictly prohibited until the embargo is lifted. Promotion of general topics and speakers is encouraged within these guidelines.

Abstract numerical discrimination learning in rats.

Science.gov (United States)

Taniuchi, Tohru; Sugihara, Junko; Wakashima, Mariko; Kamijo, Makiko

2016-06-01

In this study, we examined rats' discrimination learning of the numerical ordering positions of objects. In Experiments 1 and 2, five out of seven rats successfully learned to respond to the third of six identical objects in a row and showed reliable transfer of this discrimination to novel stimuli after being trained with three different training stimuli. In Experiment 3, the three rats from Experiment 2 continued to be trained to respond to the third object in an object array, which included an odd object that needed to be excluded when identifying the target third object. All three rats acquired this selective-counting task of specific stimuli, and two rats showed reliable transfer of this selective-counting performance to test sets of novel stimuli. In Experiment 4, the three rats from Experiment 3 quickly learned to respond to the third stimulus in object rows consisting of either six identical or six different objects. These results offer strong evidence for abstract numerical discrimination learning in rats.

A Bayesian Theory of Sequential Causal Learning and Abstract Transfer.

Science.gov (United States)

Lu, Hongjing; Rojas, Randall R; Beckers, Tom; Yuille, Alan L

2016-03-01

Two key research issues in the field of causal learning are how people acquire causal knowledge when observing data that are presented sequentially, and the level of abstraction at which learning takes place. Does sequential causal learning solely involve the acquisition of specific cause-effect links, or do learners also acquire knowledge about abstract causal constraints? Recent empirical studies have revealed that experience with one set of causal cues can dramatically alter subsequent learning and performance with entirely different cues, suggesting that learning involves abstract transfer, and such transfer effects involve sequential presentation of distinct sets of causal cues. It has been demonstrated that pre-training (or even post-training) can modulate classic causal learning phenomena such as forward and backward blocking. To account for these effects, we propose a Bayesian theory of sequential causal learning. The theory assumes that humans are able to consider and use several alternative causal generative models, each instantiating a different causal integration rule. Model selection is used to decide which integration rule to use in a given learning environment in order to infer causal knowledge from sequential data. Detailed computer simulations demonstrate that humans rely on the abstract characteristics of outcome variables (e.g., binary vs. continuous) to select a causal integration rule, which in turn alters causal learning in a variety of blocking and overshadowing paradigms. When the nature of the outcome variable is ambiguous, humans select the model that yields the best fit with the recent environment, and then apply it to subsequent learning tasks. Based on sequential patterns of cue-outcome co-occurrence, the theory can account for a range of phenomena in sequential causal learning, including various blocking effects, primacy effects in some experimental conditions, and apparently abstract transfer of causal knowledge. Copyright © 2015

The Link between Higher Order Thinking Skills, Representation and Concepts in Enhancing TIMSS Tasks

Directory of Open Access Journals (Sweden)

Nor’ain Mohd. Tajudin

2016-08-01

Full Text Available Students’ performances in TIMSS have featured strongly in recent discussions and debates about the quality of mathematical learning outcomes both from teachers and policy makers. Findings of TIMSS trends showed that most high school students in Malaysia continue to perform at less than satisfactory levels, particularly, in tasks that are cognitively demanding. In this article, we present a critical analysis of selected TIMSS Tasks and demonstrate how to support students better in the use of Higher Order Thinking Skills (HOTS in making progress with such tasks. In so doing we present analyses of TIMSS tasks and a model of these tasks that relate HOTS, representation and concepts which can be utilised by teachers to understand the role of HOTS better in empowering students shift to higher levels of cognitive funtioning in the context of tackling TIMSS and similarly demanding tasks. Our analyses and model provide an important starting point for the design of future professional development programs for Malaysian mathematics teachers in reconceptualising HOTS and implementing them in regular classrooms.

Lexical Decision with Left, Right and Center Visual Field Presentation: A Comparison between Dyslexic and Regular Readers by Means of Electrophysiological and Behavioral Measures

Science.gov (United States)

Shaul, Shelley

2012-01-01

This study examined the differences in processing between regular and dyslexic readers in a lexical decision task in different visual field presentations (left, right, and center). The research utilized behavioral measures that provide information on accuracy and reaction time and electro-physiological measures that permit the examination of brain…

Application of Turchin's method of statistical regularization

Science.gov (United States)

Zelenyi, Mikhail; Poliakova, Mariia; Nozik, Alexander; Khudyakov, Alexey

2018-04-01

During analysis of experimental data, one usually needs to restore a signal after it has been convoluted with some kind of apparatus function. According to Hadamard's definition this problem is ill-posed and requires regularization to provide sensible results. In this article we describe an implementation of the Turchin's method of statistical regularization based on the Bayesian approach to the regularization strategy.

Task-based optimization of image reconstruction in breast CT

Science.gov (United States)

Sanchez, Adrian A.; Sidky, Emil Y.; Pan, Xiaochuan

2014-03-01

We demonstrate a task-based assessment of image quality in dedicated breast CT in order to optimize the number of projection views acquired. The methodology we employ is based on the Hotelling Observer (HO) and its associated metrics. We consider two tasks: the Rayleigh task of discerning between two resolvable objects and a single larger object, and the signal detection task of classifying an image as belonging to either a signalpresent or signal-absent hypothesis. HO SNR values are computed for 50, 100, 200, 500, and 1000 projection view images, with the total imaging radiation dose held constant. We use the conventional fan-beam FBP algorithm and investigate the effect of varying the width of a Hanning window used in the reconstruction, since this affects both the noise properties of the image and the under-sampling artifacts which can arise in the case of sparse-view acquisitions. Our results demonstrate that fewer projection views should be used in order to increase HO performance, which in this case constitutes an upper-bound on human observer performance. However, the impact on HO SNR of using fewer projection views, each with a higher dose, is not as significant as the impact of employing regularization in the FBP reconstruction through a Hanning filter.

Box-and-arrow explanations need not be more abstract than neuroscientific mechanism descriptions.

Science.gov (United States)

Datteri, Edoardo; Laudisa, Federico

2014-01-01

The nature of the relationship between box-and-arrow (BA) explanations and neuroscientific mechanism descriptions (NMDs) is a key foundational issue for cognitive science. In this article we attempt to identify the nature of the constraints imposed by BA explanations on the formulation of NMDs. On the basis of a case study about motor control, we argue that BA explanations and NMDs both identify regularities that hold in the system, and that these regularities place constraints on the formulation of NMDs from BA analyses, and vice versa. The regularities identified in the two kinds of explanation play a crucial role in reasoning about the relationship between them, and in justifying the use of neuroscientific experimental techniques for the empirical testing of BA analyses of behavior. In addition, we make claims concerning the similarities and differences between BA analyses and NMDs. First, we argue that both types of explanation describe mechanisms. Second, we propose that they differ in terms of the theoretical vocabulary used to denote the entities and properties involved in the mechanism and engaging in regular, mutual interactions. On the contrary, the notion of abstractness, defined as omission of detail, does not help to distinguish BA analyses from NMDs: there is a sense in which BA analyses are more detailed than NMDs. In relation to this, we also focus on the nature of the extra detail included in NMDs and missing from BA analyses, arguing that such detail does not always concern how the system works. Finally, we propose reasons for doubting that BA analyses, unlike NMDs, may be considered "mechanism sketches." We have developed these views by critically analyzing recent claims in the philosophical literature regarding the foundations of cognitive science.

Box-and-arrow explanations need not be more abstract than neuroscientific mechanism descriptions

Directory of Open Access Journals (Sweden)

Edoardo eDatteri

2014-05-01

Full Text Available The nature of the relationship between box-and-arrow (BA explanations and neuroscientific mechanism descriptions (NMDs is a key foundational issue for cognitive science. In this article we attempt to identify the nature of the constraints imposed by BA explanations on the formulation of NMDs. On the basis of a case study about motor control, we argue that BA explanations and NMDs both identify regularities that hold in the system, and that these regularities place constraints on the formulation of NMDs from BA analyses, and vice versa. The regularities identified in the two kinds of explanation play a crucial role in reasoning about the relationship between them, and in justifying the use of neuroscientific experimental techniques for the empirical testing of BA analyses of behavior. In addition, we make claims concerning the similarities and differences between BA analyses and NMDs. First, we argue that both types of explanation describe mechanisms. Second, we propose that they differ in terms of the theoretical vocabulary used to denote the entities and properties involved in the mechanism and engaging in regular, mutual interactions. On the contrary, the notion of abstractness, defined as omission of detail, does not help to distinguish BA analyses from NMDs: there is a sense in which BA analyses are more detailed than NMDs. In relation to this, we also focus on the nature of the extra detail included in NMDs and missing from BA analyses, arguing that such detail does not always concern how the system works. Finally, we propose reasons for doubting that BA analyses, unlike NMDs, may be considered mechanism sketches. We have developed these views by critically analyzing recent claims in the philosophical literature regarding the foundations of cognitive science.

A systematic review of task- shifting for HIV treatment and care in Africa

Directory of Open Access Journals (Sweden)

Ford Nathan

2010-03-01

Full Text Available Abstract Background Shortages of human resources for health (HRH have severely hampered the rollout of antiretroviral therapy (ART in sub-Saharan Africa. Current rollout models are hospital- and physician-intensive. Task shifting, or delegating tasks performed by physicians to staff with lower-level qualifications, is considered a means of expanding rollout in resource-poor or HRH-limited settings. Methods We conducted a systematic literature review. Medline, the Cochrane library, the Social Science Citation Index, and the South African National Health Research Database were searched with the following terms: task shift*, balance of care, non-physician clinicians, substitute health care worker, community care givers, primary healthcare teams, cadres, and nurs* HIV. We mined bibliographies and corresponded with authors for further results. Grey literature was searched online, and conference proceedings searched for abstracts. Results We found 2960 articles, of which 84 were included in the core review. 51 reported outcomes, including research from 10 countries in sub-Saharan Africa. The most common intervention studied was the delegation of tasks (especially initiating and monitoring HAART from doctors to nurses and other non-physician clinicians. Five studies showed increased access to HAART through expanded clinical capacity; two concluded task shifting is cost effective; 9 showed staff equal or better quality of care; studies on non-physician clinician agreement with physician decisions was mixed, with the majority showing good agreement. Conclusions Task shifting is an effective strategy for addressing shortages of HRH in HIV treatment and care. Task shifting offers high-quality, cost-effective care to more patients than a physician-centered model. The main challenges to implementation include adequate and sustainable training, support and pay for staff in new roles, the integration of new members into healthcare teams, and the compliance of

An Abstraction Hierarchy based mobile PC display design in NPP maintenance considering the level of expertise

International Nuclear Information System (INIS)

Yim, Ho Bin; Kim, In; Seong, Poong Hyun

2011-01-01

Research highlights: → Six levels of Abstraction Hierarchy based information for maintenance were proposed. → Errors and workload with AH based information display were reduced for LL subjects. → Design concerns discovered can be applied to practical use of mobile maintenance aids. - Abstract: Recently, the importance of effective maintenance in nuclear power plants (NPPs) has been emphasized and research into effective maintenance by adopting mobile maintenance aids (MMAs) have been attempted. For improved and effective use of an MMA display design method based on the hierarchy is proposed and its design considerations are discussed in this study. Six levels of hierarchy are proposed in this paper to classify the maintenance information. By classifying and organizing maintenance information using the hierarchy, maintenance information can be used effectively by users with either high or low levels of expertise. When information classification has been finished, the information for MMA design is selected and designed. With the considerations of MMA design analysis and guidelines, a hierarchy-based MMA is designed for the maintenance tasks. An experiment is conducted using the hierarchy-based MMA in order to estimate the effectiveness of the proposed method for the maintenance tasks and to identify design considerations to enhance the proposed MMAs. The result indicated that a hierarchy-based manual was more effective than a conventional manual in terms of task completion time and number of errors. The workload for the hierarchy-based manual was estimated less than the conventional manual for subjects with low level of expertise. As the level of expertise increases, subjects tended to follow more abstract information while the number of navigations decreased. It is believed that when mobile devices become pervasive in NPP maintenance fields, the hierarchy model applied MMAs can be used as an effective maintenance supporting tool.

On the regularized fermionic projector of the vacuum

Science.gov (United States)

Finster, Felix

2008-03-01

We construct families of fermionic projectors with spherically symmetric regularization, which satisfy the condition of a distributional MP-product. The method is to analyze regularization tails with a power law or logarithmic scaling in composite expressions in the fermionic projector. The resulting regularizations break the Lorentz symmetry and give rise to a multilayer structure of the fermionic projector near the light cone. Furthermore, we construct regularizations which go beyond the distributional MP-product in that they yield additional distributional contributions supported at the origin. The remaining freedom for the regularization parameters and the consequences for the normalization of the fermionic states are discussed.

On the regularized fermionic projector of the vacuum

International Nuclear Information System (INIS)

Finster, Felix

2008-01-01

We construct families of fermionic projectors with spherically symmetric regularization, which satisfy the condition of a distributional MP-product. The method is to analyze regularization tails with a power law or logarithmic scaling in composite expressions in the fermionic projector. The resulting regularizations break the Lorentz symmetry and give rise to a multilayer structure of the fermionic projector near the light cone. Furthermore, we construct regularizations which go beyond the distributional MP-product in that they yield additional distributional contributions supported at the origin. The remaining freedom for the regularization parameters and the consequences for the normalization of the fermionic states are discussed

Songbirds and humans apply different strategies in a sound sequence discrimination task

Directory of Open Access Journals (Sweden)

Yoshimasa eSeki

2013-07-01

Full Text Available The abilities of animals and humans to extract rules from sound sequences have previously been compared using observation of spontaneous responses and conditioning techniques. However, the results were inconsistently interpreted across studies possibly due to methodological and/or species differences. Therefore, we examined the strategies for discrimination of sound sequences in Bengalese finches and humans using the same protocol. Birds were trained on a GO/NOGO task to discriminate between two categories of sound stimulus generated based on an AAB or ABB rule. The sound elements used were taken from a variety of male (M and female (F calls, such that the sequences could be represented as MMF and MFF. In test sessions, FFM and FMM sequences, which were never presented in the training sessions but conformed to the rule, were presented as probe stimuli. The results suggested two discriminative strategies were being applied: 1 memorizing sound patterns of either GO or NOGO stimuli and generating the appropriate responses for only those sounds; and 2 using the repeated element as a cue. There was no evidence that the birds successfully extracted the abstract rule (i.e. AAB and ABB; MMF-GO subjects did not produce a GO response for FFM and vice versa. Next we examined whether those strategies were also applicable for human participants on the same task. The results and questionnaires revealed that participants extracted the abstract rule, and most of them employed it to discriminate the sequences. This strategy was never observed in bird subjects, although some participants used strategies similar to the birds when responding to the probe stimuli. Our results showed that the human participants applied the abstract rule in the task even without instruction but Bengalese finches did not, thereby reconfirming that humans have to extract abstract rules from sound sequences that is distinct from non-human animals.

Songbirds and humans apply different strategies in a sound sequence discrimination task.

Science.gov (United States)

Seki, Yoshimasa; Suzuki, Kenta; Osawa, Ayumi M; Okanoya, Kazuo

2013-01-01

The abilities of animals and humans to extract rules from sound sequences have previously been compared using observation of spontaneous responses and conditioning techniques. However, the results were inconsistently interpreted across studies possibly due to methodological and/or species differences. Therefore, we examined the strategies for discrimination of sound sequences in Bengalese finches and humans using the same protocol. Birds were trained on a GO/NOGO task to discriminate between two categories of sound stimulus generated based on an "AAB" or "ABB" rule. The sound elements used were taken from a variety of male (M) and female (F) calls, such that the sequences could be represented as MMF and MFF. In test sessions, FFM and FMM sequences, which were never presented in the training sessions but conformed to the rule, were presented as probe stimuli. The results suggested two discriminative strategies were being applied: (1) memorizing sound patterns of either GO or NOGO stimuli and generating the appropriate responses for only those sounds; and (2) using the repeated element as a cue. There was no evidence that the birds successfully extracted the abstract rule (i.e., AAB and ABB); MMF-GO subjects did not produce a GO response for FFM and vice versa. Next we examined whether those strategies were also applicable for human participants on the same task. The results and questionnaires revealed that participants extracted the abstract rule, and most of them employed it to discriminate the sequences. This strategy was never observed in bird subjects, although some participants used strategies similar to the birds when responding to the probe stimuli. Our results showed that the human participants applied the abstract rule in the task even without instruction but Bengalese finches did not, thereby reconfirming that humans have to extract abstract rules from sound sequences that is distinct from non-human animals.

Conference on Hamiltonian Systems and Celestial Mechanics 2014 & Workshop on Virus Dynamics and Evolution : Extended Abstracts Spring 2014

CERN Document Server

Cors, Josep; Llibre, Jaume; Korobeinikov, Andrei

2015-01-01

The two parts of the present volume contain extended conference abstracts corresponding to selected talks given by participants at the "Conference on Hamiltonian Systems and Celestial Mechanics 2014" (HAMSYS2014) (15 abstracts) and at the "Workshop on Virus Dynamics and Evolution" (12 abstracts), both held at the Centre de Recerca Matemàtica (CRM) in Barcelona from June 2nd to 6th, 2014, and from June 23th to 27th, 2014, respectively. Most of them are brief articles, containing preliminary presentations of new results not yet published in regular research journals. The articles are the result of a direct collaboration between active researchers in the area after working in a dynamic and productive atmosphere. The first part is about Central Configurations, Periodic Orbits and Hamiltonian Systems with applications to Celestial Mechanics – a very modern and active field of research. The second part is dedicated to mathematical methods applied to viral dynamics and evolution. Mathematical modelling of biologi...

Vocal reaction times to unilaterally presented concrete and abstract words: towards a theory of differential right hemispheric semantic processing.

Science.gov (United States)

Rastatter, M; Dell, C W; McGuire, R A; Loren, C

1987-03-01

Previous studies investigating hemispheric organization for processing concrete and abstract nouns have provided conflicting results. Using manual reaction time tasks some studies have shown that the right hemisphere is capable of analyzing concrete words but not abstract. Others, however, have inferred that the left hemisphere is the sole analyzer of both types of lexicon. The present study tested these issues further by measuring vocal reaction times of normal subjects to unilaterally presented concrete and abstract items. Results were consistent with a model of functional localization which suggests that the minor hemisphere is capable of differentially processing both types of lexicon in the presence of a dominant left hemisphere.

Regularization modeling for large-eddy simulation

NARCIS (Netherlands)

Geurts, Bernardus J.; Holm, D.D.

2003-01-01

A new modeling approach for large-eddy simulation (LES) is obtained by combining a "regularization principle" with an explicit filter and its inversion. This regularization approach allows a systematic derivation of the implied subgrid model, which resolves the closure problem. The central role of

An inconclusive study comparing the effect of concrete and abstract descriptions of belief-inconsistent information.

Directory of Open Access Journals (Sweden)

Katherine A Collins

Full Text Available Linguistic bias is the differential use of linguistic abstraction (as defined by the Linguistic Category Model to describe the same behaviour for members of different groups. Essentially, it is the tendency to use concrete language for belief-inconsistent behaviours and abstract language for belief-consistent behaviours. Having found that linguistic bias is produced without intention or awareness in many contexts, researchers argue that linguistic bias reflects, reinforces, and transmits pre-existing beliefs, thus playing a role in belief maintenance. Based on the Linguistic Category Model, this assumes that concrete descriptions reduce the impact of belief-inconsistent behaviours while abstract descriptions maximize the impact of belief-consistent behaviours. However, a key study by Geschke, Sassenberg, Ruhrmann, and Sommer [2007] found that concrete descriptions of belief-inconsistent behaviours actually had a greater impact than abstract descriptions, a finding that does not fit easily within the linguistic bias paradigm. Abstract descriptions (e.g. the elderly woman is athletic are, by definition, more open to interpretation than concrete descriptions (e.g. the elderly woman works out regularly. It is thus possible that abstract descriptions are (1 perceived as having less evidentiary strength than concrete descriptions, and (2 understood in context (i.e. athletic for an elderly woman. In this study, the design of Geschke et al. [2007] was modified to address this possibility. We expected that the differences in the impact of concrete and abstract descriptions would be reduced or reversed, but instead we found that differences were largely absent. This study did not support the findings of Geschke et al. [2007] or the linguistic bias paradigm. We encourage further attempts to understand the strong effect of concrete descriptions for belief-inconsistent behaviour.

Spatially-Variant Tikhonov Regularization for Double-Difference Waveform Inversion

Energy Technology Data Exchange (ETDEWEB)

Lin, Youzuo [Los Alamos National Laboratory; Huang, Lianjie [Los Alamos National Laboratory; Zhang, Zhigang [Los Alamos National Laboratory

2011-01-01

Double-difference waveform inversion is a potential tool for quantitative monitoring for geologic carbon storage. It jointly inverts time-lapse seismic data for changes in reservoir geophysical properties. Due to the ill-posedness of waveform inversion, it is a great challenge to obtain reservoir changes accurately and efficiently, particularly when using time-lapse seismic reflection data. Regularization techniques can be utilized to address the issue of ill-posedness. The regularization parameter controls the smoothness of inversion results. A constant regularization parameter is normally used in waveform inversion, and an optimal regularization parameter has to be selected. The resulting inversion results are a trade off among regions with different smoothness or noise levels; therefore the images are either over regularized in some regions while under regularized in the others. In this paper, we employ a spatially-variant parameter in the Tikhonov regularization scheme used in double-difference waveform tomography to improve the inversion accuracy and robustness. We compare the results obtained using a spatially-variant parameter with those obtained using a constant regularization parameter and those produced without any regularization. We observe that, utilizing a spatially-variant regularization scheme, the target regions are well reconstructed while the noise is reduced in the other regions. We show that the spatially-variant regularization scheme provides the flexibility to regularize local regions based on the a priori information without increasing computational costs and the computer memory requirement.

Manifold Regularized Correlation Object Tracking.

Science.gov (United States)

Hu, Hongwei; Ma, Bo; Shen, Jianbing; Shao, Ling

2018-05-01

In this paper, we propose a manifold regularized correlation tracking method with augmented samples. To make better use of the unlabeled data and the manifold structure of the sample space, a manifold regularization-based correlation filter is introduced, which aims to assign similar labels to neighbor samples. Meanwhile, the regression model is learned by exploiting the block-circulant structure of matrices resulting from the augmented translated samples over multiple base samples cropped from both target and nontarget regions. Thus, the final classifier in our method is trained with positive, negative, and unlabeled base samples, which is a semisupervised learning framework. A block optimization strategy is further introduced to learn a manifold regularization-based correlation filter for efficient online tracking. Experiments on two public tracking data sets demonstrate the superior performance of our tracker compared with the state-of-the-art tracking approaches.

From recreational to regular drug use

DEFF Research Database (Denmark)

Järvinen, Margaretha; Ravn, Signe

2011-01-01

This article analyses the process of going from recreational use to regular and problematic use of illegal drugs. We present a model containing six career contingencies relevant for young people’s progress from recreational to regular drug use: the closing of social networks, changes in forms...

Providing Memory Management Abstraction for Self-Reconfigurable Video Processing Platforms

Directory of Open Access Journals (Sweden)

Kurt Franz Ackermann

2009-01-01

Full Text Available This paper presents a concept for an SDRAM controller targeting video processing platforms with dynamically reconfigurable processing units (RPUs. A priority-arbitration algorithm provides the required QoS and supports high bit-rate data streaming of multiple clients. Conforming to common video data structures the controller organizes the memory in partitions, frames, lines, and pixels. The raised level of abstraction drastically reduces the complexity of clients' addressing logic. Its uniform interface structure facilitates instantiations in systems with various clients. In addition to SDRAM controllers for regular applications, special demands of reconfigurable platforms have to be satisfied. The aim of this work is to minimize the number of required bus macros leading to relaxed place and route constraints and reducing the number of critical design paths. A suitable interface protocol is presented, and fundamental implementation issues are outlined.

Regular variation on measure chains

Czech Academy of Sciences Publication Activity Database

Řehák, Pavel; Vitovec, J.

2010-01-01

Roč. 72, č. 1 (2010), s. 439-448 ISSN 0362-546X R&D Projects: GA AV ČR KJB100190701 Institutional research plan: CEZ:AV0Z10190503 Keywords : regularly varying function * regularly varying sequence * measure chain * time scale * embedding theorem * representation theorem * second order dynamic equation * asymptotic properties Subject RIV: BA - General Mathematics Impact factor: 1.279, year: 2010 http://www.sciencedirect.com/science/article/pii/S0362546X09008475

New regular black hole solutions

International Nuclear Information System (INIS)

Lemos, Jose P. S.; Zanchin, Vilson T.

2011-01-01

In the present work we consider general relativity coupled to Maxwell's electromagnetism and charged matter. Under the assumption of spherical symmetry, there is a particular class of solutions that correspond to regular charged black holes whose interior region is de Sitter, the exterior region is Reissner-Nordstroem and there is a charged thin-layer in-between the two. The main physical and geometrical properties of such charged regular black holes are analyzed.

Manifold Regularized Correlation Object Tracking

OpenAIRE

Hu, Hongwei; Ma, Bo; Shen, Jianbing; Shao, Ling

2017-01-01

In this paper, we propose a manifold regularized correlation tracking method with augmented samples. To make better use of the unlabeled data and the manifold structure of the sample space, a manifold regularization-based correlation filter is introduced, which aims to assign similar labels to neighbor samples. Meanwhile, the regression model is learned by exploiting the block-circulant structure of matrices resulting from the augmented translated samples over multiple base samples cropped fr...

On geodesics in low regularity

Science.gov (United States)

Sämann, Clemens; Steinbauer, Roland

2018-02-01

We consider geodesics in both Riemannian and Lorentzian manifolds with metrics of low regularity. We discuss existence of extremal curves for continuous metrics and present several old and new examples that highlight their subtle interrelation with solutions of the geodesic equations. Then we turn to the initial value problem for geodesics for locally Lipschitz continuous metrics and generalize recent results on existence, regularity and uniqueness of solutions in the sense of Filippov.

Semantic Size of Abstract Concepts: It Gets Emotional When You Can’t See It

Science.gov (United States)

Yao, Bo; Vasiljevic, Milica; Weick, Mario; Sereno, Margaret E.; O’Donnell, Patrick J.; Sereno, Sara C.

2013-01-01

Size is an important visuo-spatial characteristic of the physical world. In language processing, previous research has demonstrated a processing advantage for words denoting semantically “big” (e.g., jungle) versus “small” (e.g., needle) concrete objects. We investigated whether semantic size plays a role in the recognition of words expressing abstract concepts (e.g., truth). Semantically “big” and “small” concrete and abstract words were presented in a lexical decision task. Responses to “big” words, regardless of their concreteness, were faster than those to “small” words. Critically, we explored the relationship between semantic size and affective characteristics of words as well as their influence on lexical access. Although a word’s semantic size was correlated with its emotional arousal, the temporal locus of arousal effects may depend on the level of concreteness. That is, arousal seemed to have an earlier (lexical) effect on abstract words, but a later (post-lexical) effect on concrete words. Our findings provide novel insights into the semantic representations of size in abstract concepts and highlight that affective attributes of words may not always index lexical access. PMID:24086421

Program and abstracts

Energy Technology Data Exchange (ETDEWEB)

1975-01-01

Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled:Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Physics Education; SANCGASS; Astronomy; Plasma Physics; Physics in Industry; Applied and General Physics.

Program and abstracts

International Nuclear Information System (INIS)

1975-01-01

Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled:Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Physics Education; SANCGASS; Astronomy; Plasma Physics; Physics in Industry; Applied and General Physics

Proceedings of the first meeting of IEA, Bioenergy, Task 17

Energy Technology Data Exchange (ETDEWEB)

Christersson, L.; Ledin, S. [eds.

1999-07-01

The present proceedings are the result of the first meeting of Task 17 within the frame of IEA, Bioenergy. During the meeting the objectives of Task 17 were discussed and determined to be: * to stimulate the full-scale implementation of energy crops in participating countries; * to strengthen the contacts and co-operation between participating countries, scientists, biomass producers, machine developers, entrepreneurs, and end users; * to select the most urgent research and development areas, and to suggest projects of co-operation; * to deliver Proceedings from the meetings, and * to inform Ex-Co-members. Separate abstracts have been prepared for all the 7 papers presented.

Evaluation of modular robot system for maintenance tasks in hot cell

Energy Technology Data Exchange (ETDEWEB)

Pagala, Prithvi Sekhar, E-mail: ps.pagala@upm.es [Centre for Automation and Robotics UPM-CSIC (Spain); Ferre, Manuel, E-mail: m.ferre@upm.es [Centre for Automation and Robotics UPM-CSIC (Spain); Orona, Luis, E-mail: l.orona@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung (Germany)

2014-10-15

Highlights: •Modular robot deployment inside hot cell for remote manipulation evaluated. •Flexible and adaptable system for variety of tasks presented. •Uses in large workspaces and evolving requirements shown. -- Abstract: This work assesses the use of a modular robot system to perform maintenance and inspection tasks such as, remote flexible inspection, manipulation and cooperation with deployed systems inside the hot cell. A flexible modular solution for the inclusion in maintenance operations is presented. The proposed heterogeneous modular robotic system is evaluated using simulations of the prototype across selected robot configuration to perform tasks. Results obtained show the advantages and ability of the modular robot to perform the necessary tasks as well as its ability to adapt and evolve depending on the need. The simulation test case inside hot cell shows modular robot configuration, a two modular arm to perform tele-operation tasks in the workspace and a wheeled platform for inspection collaborating to perform tasks. The advantage of using re-configurable modular robot over conventional robot platforms is shown.

Program and abstracts

International Nuclear Information System (INIS)

1976-01-01

Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled: Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Plasma Physics; Solar-Terrestrial Physics; Astrophysics and Astronomy; Radioastronomy; General Physics; Applied Physics; Industrial Physics

Introduction to abstract algebra

CERN Document Server

Nicholson, W Keith

2012-01-01

Praise for the Third Edition ". . . an expository masterpiece of the highest didactic value that has gained additional attractivity through the various improvements . . ."-Zentralblatt MATH The Fourth Edition of Introduction to Abstract Algebra continues to provide an accessible approach to the basic structures of abstract algebra: groups, rings, and fields. The book's unique presentation helps readers advance to abstract theory by presenting concrete examples of induction, number theory, integers modulo n, and permutations before the abstract structures are defined. Readers can immediately be

Laplacian manifold regularization method for fluorescence molecular tomography

Science.gov (United States)

He, Xuelei; Wang, Xiaodong; Yi, Huangjian; Chen, Yanrong; Zhang, Xu; Yu, Jingjing; He, Xiaowei

2017-04-01

Sparse regularization methods have been widely used in fluorescence molecular tomography (FMT) for stable three-dimensional reconstruction. Generally, ℓ1-regularization-based methods allow for utilizing the sparsity nature of the target distribution. However, in addition to sparsity, the spatial structure information should be exploited as well. A joint ℓ1 and Laplacian manifold regularization model is proposed to improve the reconstruction performance, and two algorithms (with and without Barzilai-Borwein strategy) are presented to solve the regularization model. Numerical studies and in vivo experiment demonstrate that the proposed Gradient projection-resolved Laplacian manifold regularization method for the joint model performed better than the comparative algorithm for ℓ1 minimization method in both spatial aggregation and location accuracy.

Learning Sparse Visual Representations with Leaky Capped Norm Regularizers

OpenAIRE

Wangni, Jianqiao; Lin, Dahua

2017-01-01

Sparsity inducing regularization is an important part for learning over-complete visual representations. Despite the popularity of $\\ell_1$ regularization, in this paper, we investigate the usage of non-convex regularizations in this problem. Our contribution consists of three parts. First, we propose the leaky capped norm regularization (LCNR), which allows model weights below a certain threshold to be regularized more strongly as opposed to those above, therefore imposes strong sparsity and...

Abstracting Concepts and Methods.

Science.gov (United States)

Borko, Harold; Bernier, Charles L.

This text provides a complete discussion of abstracts--their history, production, organization, publication--and of indexing. Instructions for abstracting are outlined, and standards and criteria for abstracting are stated. Management, automation, and personnel are discussed in terms of possible economies that can be derived from the introduction…

Tiling as a Durable Abstraction for Parallelism and Data Locality

Energy Technology Data Exchange (ETDEWEB)

Unat, Didem [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chan, Cy P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Zhang, Weiqun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bell, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shalf, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2013-11-18

Tiling is a useful loop transformation for expressing parallelism and data locality. Automated tiling transformations that preserve data-locality are increasingly important due to hardware trends towards massive parallelism and the increasing costs of data movement relative to the cost of computing. We propose TiDA as a durable tiling abstraction that centralizes parameterized tiling information within array data types with minimal changes to the source code. The data layout information can be used by the compiler and runtime to automatically manage parallelism, optimize data locality, and schedule tasks intelligently. In this study, we present the design features and early interface of TiDA along with some preliminary results.

Adaptive regularization of noisy linear inverse problems

DEFF Research Database (Denmark)

Hansen, Lars Kai; Madsen, Kristoffer Hougaard; Lehn-Schiøler, Tue

2006-01-01

In the Bayesian modeling framework there is a close relation between regularization and the prior distribution over parameters. For prior distributions in the exponential family, we show that the optimal hyper-parameter, i.e., the optimal strength of regularization, satisfies a simple relation: T......: The expectation of the regularization function, i.e., takes the same value in the posterior and prior distribution. We present three examples: two simulations, and application in fMRI neuroimaging....

Exclusion of children with intellectual disabilities from regular ...

African Journals Online (AJOL)

Study investigated why teachers exclude children with intellectual disability from the regular classrooms in Nigeria. Participants were, 169 regular teachers randomly selected from Oyo and Ogun states. Questionnaire was used to collect data result revealed that 57.4% regular teachers could not cope with children with ID ...

Comprehension of concrete and abstract words in semantic variant primary progressive aphasia and Alzheimer's disease: A behavioral and neuroimaging study.

Science.gov (United States)

Joubert, Sven; Vallet, Guillaume T; Montembeault, Maxime; Boukadi, Mariem; Wilson, Maximiliano A; Laforce, Robert Jr; Rouleau, Isabelle; Brambati, Simona M

2017-07-01

The aim of this study was to investigate the comprehension of concrete, abstract and abstract emotional words in semantic variant primary progressive aphasia (svPPA), Alzheimer's disease (AD), and healthy elderly adults (HE) Three groups of participants (9 svPPA, 12 AD, 11 HE) underwent a general neuropsychological assessment, a similarity judgment task, and structural brain MRI. The three types of words were processed similarly in the group of AD participants. In contrast, patients in the svPPA group were significantly more impaired at processing concrete words than abstract words, while comprehension of abstract emotional words was in between. VBM analyses showed that comprehension of concrete words relative to abstract words was significantly correlated with atrophy in the left anterior temporal lobe. These results support the view that concrete words are disproportionately impaired in svPPA, and that concrete and abstract words may rely upon partly dissociable brain regions. Copyright © 2017 Elsevier Inc. All rights reserved.

On infinite regular and chiral maps

OpenAIRE

Arredondo, John A.; Valdez, Camilo Ramírez y Ferrán

2015-01-01

We prove that infinite regular and chiral maps take place on surfaces with at most one end. Moreover, we prove that an infinite regular or chiral map on an orientable surface with genus can only be realized on the Loch Ness monster, that is, the topological surface of infinite genus with one end.

29 CFR 779.18 - Regular rate.

Science.gov (United States)

2010-07-01

... employee under subsection (a) or in excess of the employee's normal working hours or regular working hours... Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR... not less than one and one-half times their regular rates of pay. Section 7(e) of the Act defines...

Completeness of Lyapunov Abstraction

Directory of Open Access Journals (Sweden)

Rafael Wisniewski

2013-08-01

Full Text Available In this work, we continue our study on discrete abstractions of dynamical systems. To this end, we use a family of partitioning functions to generate an abstraction. The intersection of sub-level sets of the partitioning functions defines cells, which are regarded as discrete objects. The union of cells makes up the state space of the dynamical systems. Our construction gives rise to a combinatorial object - a timed automaton. We examine sound and complete abstractions. An abstraction is said to be sound when the flow of the time automata covers the flow lines of the dynamical systems. If the dynamics of the dynamical system and the time automaton are equivalent, the abstraction is complete. The commonly accepted paradigm for partitioning functions is that they ought to be transversal to the studied vector field. We show that there is no complete partitioning with transversal functions, even for particular dynamical systems whose critical sets are isolated critical points. Therefore, we allow the directional derivative along the vector field to be non-positive in this work. This considerably complicates the abstraction technique. For understanding dynamical systems, it is vital to study stable and unstable manifolds and their intersections. These objects appear naturally in this work. Indeed, we show that for an abstraction to be complete, the set of critical points of an abstraction function shall contain either the stable or unstable manifold of the dynamical system.

Continuum regularized Yang-Mills theory

International Nuclear Information System (INIS)

Sadun, L.A.

1987-01-01

Using the machinery of stochastic quantization, Z. Bern, M. B. Halpern, C. Taubes and I recently proposed a continuum regularization technique for quantum field theory. This regularization may be implemented by applying a regulator to either the (d + 1)-dimensional Parisi-Wu Langevin equation or, equivalently, to the d-dimensional second order Schwinger-Dyson (SD) equations. This technique is non-perturbative, respects all gauge and Lorentz symmetries, and is consistent with a ghost-free gauge fixing (Zwanziger's). This thesis is a detailed study of this regulator, and of regularized Yang-Mills theory, using both perturbative and non-perturbative techniques. The perturbative analysis comes first. The mechanism of stochastic quantization is reviewed, and a perturbative expansion based on second-order SD equations is developed. A diagrammatic method (SD diagrams) for evaluating terms of this expansion is developed. We apply the continuum regulator to a scalar field theory. Using SD diagrams, we show that all Green functions can be rendered finite to all orders in perturbation theory. Even non-renormalizable theories can be regularized. The continuum regulator is then applied to Yang-Mills theory, in conjunction with Zwanziger's gauge fixing. A perturbative expansion of the regulator is incorporated into the diagrammatic method. It is hoped that the techniques discussed in this thesis will contribute to the construction of a renormalized Yang-Mills theory is 3 and 4 dimensions

Estimation Accuracy on Execution Time of Run-Time Tasks in a Heterogeneous Distributed Environment

Directory of Open Access Journals (Sweden)

Qi Liu

2016-08-01

Full Text Available Distributed Computing has achieved tremendous development since cloud computing was proposed in 2006, and played a vital role promoting rapid growth of data collecting and analysis models, e.g., Internet of things, Cyber-Physical Systems, Big Data Analytics, etc. Hadoop has become a data convergence platform for sensor networks. As one of the core components, MapReduce facilitates allocating, processing and mining of collected large-scale data, where speculative execution strategies help solve straggler problems. However, there is still no efficient solution for accurate estimation on execution time of run-time tasks, which can affect task allocation and distribution in MapReduce. In this paper, task execution data have been collected and employed for the estimation. A two-phase regression (TPR method is proposed to predict the finishing time of each task accurately. Detailed data of each task have drawn interests with detailed analysis report being made. According to the results, the prediction accuracy of concurrent tasks’ execution time can be improved, in particular for some regular jobs.

Relationship between physical fitness and game-related statistics in elite professional basketball players: Regular season vs. playoffs

Directory of Open Access Journals (Sweden)

João Henrique Gomes

2017-05-01

Full Text Available Abstract AIMS This study aimed to verify th erelation ship between of anthropometric and physical performance variables with game-related statistics in professional elite basketball players during a competition. METHODS Eleven male basketball players were evaluated during 10 weeks in two distinct moments (regular season and playoffs. Overall, 11 variables of physical fitness and 13 variables of game-related statistics were analysed. RESULTS The following significant Pearson’scorrelations were found in regular season: percentage of fat mass with assists (r = -0.62 and steals (r = -0.63; height (r = 0.68, lean mass (r = 0.64, and maximum strength (r = 0.67 with blocks; squat jump with steals (r = 0.63; and time in the T-test with success ful two-point field-goals (r = -0.65, success ful free-throws (r = -0.61, and steals (r = -0.62. However, in playoffs, only stature and lean mass maintained these correlations (p ≤ 0.05. CONCLUSIONS The anthropometric and physical characteristics of the players showed few correlations with the game-related statistics in regular season, and these correlations are even lower in the playoff games of a professional elite Champion ship, wherefore, not being good predictors of technical performance.

Abstract algebra

CERN Document Server

Garrett, Paul B

2007-01-01

Designed for an advanced undergraduate- or graduate-level course, Abstract Algebra provides an example-oriented, less heavily symbolic approach to abstract algebra. The text emphasizes specifics such as basic number theory, polynomials, finite fields, as well as linear and multilinear algebra. This classroom-tested, how-to manual takes a more narrative approach than the stiff formalism of many other textbooks, presenting coherent storylines to convey crucial ideas in a student-friendly, accessible manner. An unusual feature of the text is the systematic characterization of objects by universal

Abstracts and abstracting a genre and set of skills for the twenty-first century

CERN Document Server

Koltay, Tibor

2010-01-01

Despite their changing role, abstracts remain useful in the digital world. Highly beneficial to information professionals and researchers who work and publish in different fields, this book summarizes the most important and up-to-date theory of abstracting, as well as giving advice and examples for the practice of writing different kinds of abstracts. The book discusses the length, the functions and basic structure of abstracts, outlining a new approach to informative and indicative abstracts. The abstractors' personality, their linguistic and non-linguistic knowledge and skills are also discu

Truthful Monadic Abstractions

DEFF Research Database (Denmark)

Brock-Nannestad, Taus; Schürmann, Carsten

2012-01-01

indefinitely, finding neither a proof nor a disproof of a given subgoal. In this paper we characterize a family of truth-preserving abstractions from intuitionistic first-order logic to the monadic fragment of classical first-order logic. Because they are truthful, these abstractions can be used to disprove...

Regularity effect in prospective memory during aging

OpenAIRE

Blondelle, Geoffrey; Hainselin, Mathieu; Gounden, Yannick; Heurley, Laurent; Voisin, Hélène; Megalakaki, Olga; Bressous, Estelle; Quaglino, Véronique

2016-01-01

Background: Regularity effect can affect performance in prospective memory (PM), but little is known on the cognitive processes linked to this effect. Moreover, its impacts with regard to aging remain unknown. To our knowledge, this study is the first to examine regularity effect in PM in a lifespan perspective, with a sample of young, intermediate, and older adults.Objective and design: Our study examined the regularity effect in PM in three groups of participants: 28 young adults (18–30), 1...

The left inferior frontal gyrus: A neural crossroads between abstract and concrete knowledge.

Science.gov (United States)

Della Rosa, Pasquale Anthony; Catricalà, Eleonora; Canini, Matteo; Vigliocco, Gabriella; Cappa, Stefano F

2018-07-15

Evidence from both neuropsychology and neuroimaging suggests that different types of information are necessary for representing and processing concrete and abstract word meanings. Both abstract and concrete concepts, however, conjointly rely on perceptual, verbal and contextual knowledge, with abstract concepts characterized by low values of imageability (IMG) (low sensory-motor grounding) and low context availability (CA) (more difficult to contextualize). Imaging studies supporting differences between abstract and concrete concepts show a greater recruitment of the left inferior frontal gyrus (LIFG) for abstract concepts, which has been attributed either to the representation of abstract-specific semantic knowledge or to the request for more executive control than in the case of concrete concepts. We conducted an fMRI study on 27 participants, using a lexical decision task involving both abstract and concrete words, whose IMG and CA values were explicitly modelled in separate parametric analyses. The LIFG was significantly more activated for abstract than for concrete words, and a conjunction analysis showed a common activation for words with low IMG or low CA only in the LIFG, in the same area reported for abstract words. A regional template map of brain activations was then traced for words with low IMG or low CA, and BOLD regional time-series were extracted and correlated with the specific LIFG neural activity elicited for abstract words. The regions associated to low IMG, which were functionally correlated with LIFG, were mainly in the left hemisphere, while those associated with low CA were in the right hemisphere. Finally, in order to reveal which LIFG-related network increased its connectivity with decreases of IMG or CA, we conducted generalized psychophysiological interaction analyses. The connectivity strength values extracted from each region connected with the LIFG were correlated with specific LIFG neural activity for abstract words, and a regression

20 CFR 226.14 - Employee regular annuity rate.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Employee regular annuity rate. 226.14 Section... COMPUTING EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Computing an Employee Annuity § 226.14 Employee regular annuity rate. The regular annuity rate payable to the employee is the total of the employee tier I...

Sheltering the self from the storm: self-construal abstractness and the stability of self-esteem.

Science.gov (United States)

Updegraff, John A; Emanuel, Amber S; Suh, Eunkook M; Gallagher, Kristel M

2010-01-01

Self-construal abstractness (SCA) refers to the degree to which people construe important bases of self-esteem in a broad, flexible, and abstract rather than a concrete and specific manner. This article hypothesized that SCA would be a unique predictor of self-esteem stability, capturing the degree to which people's most important bases of self-worth are resistant to disconfirmation. Two studies using a daily diary methodology examined relationships between SCA, daily self-esteem, and daily emotions and/or events. In Study 1, individual differences in SCA emerged as the most consistent and unique predictor of self-esteem stability. Furthermore, SCA contributed to self-esteem stability by buffering the influence of daily negative emotions on self-esteem. Study 2 manipulated SCA via a daily self-construal task and found an abstract versus concrete self-focus to buffer the influence of daily negative events on self-esteem. Implications of these findings for the study of the self and well-being are discussed.

Task Complexity Modulates Sleep-Related Offline Learning in Sequential Motor Skills

Directory of Open Access Journals (Sweden)

Klaus Blischke

2017-07-01

Full Text Available Recently, a number of authors have advocated the introduction of gross motor tasks into research on sleep-related motor offline learning. Such tasks are often designed to be more complex than traditional key-pressing tasks. However, until now, little effort has been undertaken to scrutinize the role of task complexity in any systematic way. Therefore, the effect of task complexity on the consolidation of gross motor sequence memory was examined by our group in a series of three experiments. Criterion tasks always required participants to produce unrestrained arm movement sequences by successively fitting a small peg into target holes on a pegboard. The sequences always followed a certain spatial pattern in the horizontal plane. The targets were visualized prior to each transport movement on a computer screen. The tasks differed with respect to sequence length and structural complexity. In each experiment, half of the participants initially learned the task in the morning and were retested 12 h later following a wake retention interval. The other half of the subjects underwent practice in the evening and was retested 12 h later following a night of sleep. The dependent variables were the error rate and total sequence execution time (inverse to the sequence execution speed. Performance generally improved during acquisition. The error rate was always low and remained stable during retention. The sequence execution time significantly decreased again following sleep but not after waking when the sequence length was long and structural complexity was high. However, sleep-related offline improvements were absent when the sequence length was short or when subjects performed a highly regular movement pattern. It is assumed that the occurrence of sleep-related offline performance improvements in sequential motor tasks is associated with a sufficient amount of motor task complexity.

Regular algebra and finite machines

CERN Document Server

Conway, John Horton

2012-01-01

World-famous mathematician John H. Conway based this classic text on a 1966 course he taught at Cambridge University. Geared toward graduate students of mathematics, it will also prove a valuable guide to researchers and professional mathematicians.His topics cover Moore's theory of experiments, Kleene's theory of regular events and expressions, Kleene algebras, the differential calculus of events, factors and the factor matrix, and the theory of operators. Additional subjects include event classes and operator classes, some regulator algebras, context-free languages, communicative regular alg

39 CFR 6.1 - Regular meetings, annual meeting.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Regular meetings, annual meeting. 6.1 Section 6.1 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE MEETINGS (ARTICLE VI) § 6.1 Regular meetings, annual meeting. The Board shall meet regularly on a schedule...

Commercial Database Design vs. Library Terminology Comprehension: Why Do Students Print Abstracts Instead of Full-Text Articles?

Science.gov (United States)

Imler, Bonnie; Eichelberger, Michelle

2014-01-01

When asked to print the full text of an article, many undergraduate college students print the abstract instead of the full text. This study seeks to determine the underlying cause(s) of this confusion. In this quantitative study, participants (n = 40) performed five usability tasks to assess ease of use and usefulness of five commercial library…

Exercise intensities of gardening tasks within older adult allotment gardeners in Wales.

Science.gov (United States)

Hawkins, Jemma L; Smith, Alexander; Backx, Karianne; Clayton, Deborah A

2015-04-01

Previous research has suggested that gardening activity could be an effective form of regular exercise for improving physical and psychological health in later life. However, there is a lack of data regarding the exercise intensities of various gardening tasks across different types of gardening and different populations. The purpose of this study was to examine the exercise intensity of gardening activity for older adult allotment gardeners in Wales, United Kingdom following a similar procedure used in previous studies conducted in the United States and South Korea by Park and colleagues (2008a; 2011). Oxygen consumption (VO2) and energy expenditure for six gardening tasks were measured via indirect calorimetery using the portable Oxycon mobile device. From these measures, estimated metabolic equivalent units (METs) were calculated. Consistent with Park et al. (2008a; 2011) the six gardening tasks were classified as low to moderate-high intensity physical activities based on their metabolic values (1.9-5.7 METs).

Abstracts

Institute of Scientific and Technical Information of China (English)

2011-01-01

The Western Theories of War Ethics and Contemporary Controversies Li Xiaodong U Ruijing （4） [ Abstract] In the field of international relations, war ethics is a concept with distinct westem ideological color. Due to factors of history and reality, the in

Cognitive demand of human sensorimotor performance during an extended space mission: a dual-task study.

Science.gov (United States)

Bock, Otmar; Weigelt, Cornelia; Bloomberg, Jacob J

2010-09-01

Two previous single-case studies found that the dual-task costs of manual tracking plus memory search increased during a space mission, and concluded that sensorimotor deficits during spaceflight may be related to cognitive overload. Since dual-task costs were insensitive to the difficulty of memory search, the authors argued that the overload may reflect stress-related problems of multitasking, rather than a scarcity of specific cognitive resources. Here we expand the available database and compare different types of concurrent task. Three subjects were repeatedly tested before, during, and after an extended mission on the International Space Station (ISS). They performed an unstable tracking task and four reaction-time tasks, both separately and concurrently. Inflight data could only be obtained during later parts of the mission. The tracking error increased from pre- to in flight by a factor of about 2, both under single- and dual-task conditions. The dual-task costs with a reaction-time task requiring rhythm production was 2.4 times higher than with a reaction-time task requiring visuo-spatial transformations, and 8 times higher than with a regular choice reaction-time task. Long-term sensorimotor deficits during spaceflight may reflect not only stress, but also a scarcity of resources related to complex motor programming; possibly those resources are tied up by sensorimotor adaptation to the space environment.

A regularized stationary mean-field game

KAUST Repository

Yang, Xianjin

2016-01-01

In the thesis, we discuss the existence and numerical approximations of solutions of a regularized mean-field game with a low-order regularization. In the first part, we prove a priori estimates and use the continuation method to obtain the existence of a solution with a positive density. Finally, we introduce the monotone flow method and solve the system numerically.

A regularized stationary mean-field game

KAUST Repository

Yang, Xianjin

2016-04-19

In the thesis, we discuss the existence and numerical approximations of solutions of a regularized mean-field game with a low-order regularization. In the first part, we prove a priori estimates and use the continuation method to obtain the existence of a solution with a positive density. Finally, we introduce the monotone flow method and solve the system numerically.

Automating InDesign with Regular Expressions

CERN Document Server

Kahrel, Peter

2006-01-01

If you need to make automated changes to InDesign documents beyond what basic search and replace can handle, you need regular expressions, and a bit of scripting to make them work. This Short Cut explains both how to write regular expressions, so you can find and replace the right things, and how to use them in InDesign specifically.

Understanding of action-related and abstract verbs in comparison: a behavioral and TMS study.

Science.gov (United States)

Innocenti, Alessandro; De Stefani, Elisa; Sestito, Mariateresa; Gentilucci, Maurizio

2014-02-01

Does the comprehension of both action-related and abstract verbs rely on motor simulation? In a behavioral experiment, in which a semantic task was used, response times to hand-action-related verbs were briefer than those to abstract verbs and both decreased with repetition of presentation. In a transcranial magnetic stimulation (TMS) experiment, single-pulse stimulation was randomly delivered over hand motor area of the left primary motor cortex to measure cortical-spinal excitability at 300 or 500 ms after verb presentation. Two blocks of trials were run. In each block, the same verbs were randomly presented. In the first block, stimulation induced an increase in motor evoked potentials only when TMS was applied 300 ms after action-related verb presentation. In the second block, no modulation of motor cortex was found according to type of verb and stimulation-delay. These results confirm that motor simulation can be used to understand action rather than abstract verbs. Moreover, they suggest that with repetition, the semantic processing for action verbs does not require activation of primary motor cortex anymore.

Optimal behaviour can violate the principle of regularity.

Science.gov (United States)

Trimmer, Pete C

2013-07-22

Understanding decisions is a fundamental aim of behavioural ecology, psychology and economics. The regularity axiom of utility theory holds that a preference between options should be maintained when other options are made available. Empirical studies have shown that animals violate regularity but this has not been understood from a theoretical perspective, such decisions have therefore been labelled as irrational. Here, I use models of state-dependent behaviour to demonstrate that choices can violate regularity even when behavioural strategies are optimal. I also show that the range of conditions over which regularity should be violated can be larger when options do not always persist into the future. Consequently, utility theory--based on axioms, including transitivity, regularity and the independence of irrelevant alternatives--is undermined, because even alternatives that are never chosen by an animal (in its current state) can be relevant to a decision.

Dimensional regularization in configuration space

International Nuclear Information System (INIS)

Bollini, C.G.; Giambiagi, J.J.

1995-09-01

Dimensional regularization is introduced in configuration space by Fourier transforming in D-dimensions the perturbative momentum space Green functions. For this transformation, Bochner theorem is used, no extra parameters, such as those of Feynman or Bogoliubov-Shirkov are needed for convolutions. The regularized causal functions in x-space have ν-dependent moderated singularities at the origin. They can be multiplied together and Fourier transformed (Bochner) without divergence problems. The usual ultraviolet divergences appear as poles of the resultant functions of ν. Several example are discussed. (author). 9 refs

Matrix regularization of 4-manifolds

OpenAIRE

Trzetrzelewski, M.

2012-01-01

We consider products of two 2-manifolds such as S^2 x S^2, embedded in Euclidean space and show that the corresponding 4-volume preserving diffeomorphism algebra can be approximated by a tensor product SU(N)xSU(N) i.e. functions on a manifold are approximated by the Kronecker product of two SU(N) matrices. A regularization of the 4-sphere is also performed by constructing N^2 x N^2 matrix representations of the 4-algebra (and as a byproduct of the 3-algebra which makes the regularization of S...

On the equivalence of different regularization methods

International Nuclear Information System (INIS)

Brzezowski, S.

1985-01-01

The R-circunflex-operation preceded by the regularization procedure is discussed. Some arguments are given, according to which the results may depend on the method of regularization, introduced in order to avoid divergences in perturbation calculations. 10 refs. (author)

Accreting fluids onto regular black holes via Hamiltonian approach

Energy Technology Data Exchange (ETDEWEB)

Jawad, Abdul [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan); Shahzad, M.U. [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan); University of Central Punjab, CAMS, UCP Business School, Lahore (Pakistan)

2017-08-15

We investigate the accretion of test fluids onto regular black holes such as Kehagias-Sfetsos black holes and regular black holes with Dagum distribution function. We analyze the accretion process when different test fluids are falling onto these regular black holes. The accreting fluid is being classified through the equation of state according to the features of regular black holes. The behavior of fluid flow and the existence of sonic points is being checked for these regular black holes. It is noted that the three-velocity depends on critical points and the equation of state parameter on phase space. (orig.)

Skylab task and work performance /Experiment M-151 - Time and motion study/

Science.gov (United States)

Kubis, J. F.; Mclaughlin, E. J.

1975-01-01

The primary objective of Experiment M151 was to study the inflight adaptation of Skylab crewmen to a variety of task situations involving different types of activity. A parallel objective was to examine astronaut inflight performance for any behavioral stress effects associated with the working and living conditions of the Skylab environment. Training data provided the basis for comparison of preflight and inflight performance. Efficiency was evaluated through the adaptation function, namely, the relation of performance time over task trials. The results indicate that the initial changeover from preflight to inflight was accompanied by a substantial increase in performance time for most work and task activities. Equally important was the finding that crewmen adjusted rapidly to the weightless environment and became proficient in developing techniques with which to optimize task performance. By the end of the second inflight trial, most of the activities were performed almost as efficiently as on the last preflight trial. The analysis demonstrated the sensitivity of the adaptation function to differences in task and hardware configurations. The function was found to be more regular and less variable inflight than preflight. Translation and control of masses were accomplished easily and efficiently through the rapid development of the arms and legs as subtle guidance and restraint systems.

Sophisticated Search Capabilities in the ADS Abstract Service

Science.gov (United States)

Eichhorn, G.; Accomazzi, A.; Grant, C. S.; Henneken, E.; Kurtz, M. J.; Murray, S. S.

2003-12-01

The ADS provides access to over 940,000 references from astronomy and planetary sciences publications and 1.5 million records from physics publications. It is funded by NASA and provides free access to these references, as well as to 2.4 million scanned pages from the astronomical literature. These include most of the major astronomy and several planetary sciences journals, as well as many historical observatory publications. The references now include the abstracts from all volumes of the Journal of Geophysical Research (JGR) since the beginning of 2002. We get these abstracts on a regular basis. The Kluwer journal Solar Physics has been scanned back to volume 1 and is available through the ADS. We have extracted the reference lists from this and many other journals and included them in the reference and citation database of the ADS. We have recently scanning Earth, Moon and Planets, another Kluwer journal, and will scan other Kluwer journals in the future as well. We plan on extracting references from these journals as well in the near future. The ADS has many sophisticated query features. These allow the user to formulate complex queries. Using results lists to get further information about the selected articles provide the means to quickly find important and relevant articles from the database. Three advanced feedback queries are available from the bottom of the ADS results list (in addition to regular feedback queries already available from the abstract page and from the bottom of the results list): 1. Get reference list for selected articles: This query returns all known references for the selected articles (or for all articles in the first list). The resulting list will be ranked according to how often each article is referred to and will show the most referenced articles in the field of study that created the first list. It presumably shows the most important articles in that field. 2. Get citation list for selected articles: This returns all known articles

Reward Anticipation in Ventral Striatum and Individual Sensitivity to Reward : A Pilot Study of a Child-Friendly fMRI Task

NARCIS (Netherlands)

van Hulst, Branko M; de Zeeuw, Patrick; Lupas, Kellina; Bos, Dienke J; Neggers, Sebastiaan F W; Durston, Sarah

2015-01-01

Reward processing has been implicated in developmental disorders. However, the classic task to probe reward anticipation, the monetary incentive delay task, has an abstract coding of reward and no storyline and may therefore be less appropriate for use with developmental populations. We modified the

Check Sample Abstracts.

Science.gov (United States)

Alter, David; Grenache, David G; Bosler, David S; Karcher, Raymond E; Nichols, James; Rajadhyaksha, Aparna; Camelo-Piragua, Sandra; Rauch, Carol; Huddleston, Brent J; Frank, Elizabeth L; Sluss, Patrick M; Lewandrowski, Kent; Eichhorn, John H; Hall, Janet E; Rahman, Saud S; McPherson, Richard A; Kiechle, Frederick L; Hammett-Stabler, Catherine; Pierce, Kristin A; Kloehn, Erica A; Thomas, Patricia A; Walts, Ann E; Madan, Rashna; Schlesinger, Kathie; Nawgiri, Ranjana; Bhutani, Manoop; Kanber, Yonca; Abati, Andrea; Atkins, Kristen A; Farrar, Robert; Gopez, Evelyn Valencerina; Jhala, Darshana; Griffin, Sonya; Jhala, Khushboo; Jhala, Nirag; Bentz, Joel S; Emerson, Lyska; Chadwick, Barbara E; Barroeta, Julieta E; Baloch, Zubair W; Collins, Brian T; Middleton, Owen L; Davis, Gregory G; Haden-Pinneri, Kathryn; Chu, Albert Y; Keylock, Joren B; Ramoso, Robert; Thoene, Cynthia A; Stewart, Donna; Pierce, Arand; Barry, Michelle; Aljinovic, Nika; Gardner, David L; Barry, Michelle; Shields, Lisa B E; Arnold, Jack; Stewart, Donna; Martin, Erica L; Rakow, Rex J; Paddock, Christopher; Zaki, Sherif R; Prahlow, Joseph A; Stewart, Donna; Shields, Lisa B E; Rolf, Cristin M; Falzon, Andrew L; Hudacki, Rachel; Mazzella, Fermina M; Bethel, Melissa; Zarrin-Khameh, Neda; Gresik, M Vicky; Gill, Ryan; Karlon, William; Etzell, Joan; Deftos, Michael; Karlon, William J; Etzell, Joan E; Wang, Endi; Lu, Chuanyi M; Manion, Elizabeth; Rosenthal, Nancy; Wang, Endi; Lu, Chuanyi M; Tang, Patrick; Petric, Martin; Schade, Andrew E; Hall, Geraldine S; Oethinger, Margret; Hall, Geraldine; Picton, Avis R; Hoang, Linda; Imperial, Miguel Ranoa; Kibsey, Pamela; Waites, Ken; Duffy, Lynn; Hall, Geraldine S; Salangsang, Jo-Anne M; Bravo, Lulette Tricia C; Oethinger, Margaret D; Veras, Emanuela; Silva, Elvia; Vicens, Jimena; Silva, Elvio; Keylock, Joren; Hempel, James; Rushing, Elizabeth; Posligua, Lorena E; Deavers, Michael T; Nash, Jason W; Basturk, Olca; Perle, Mary Ann; Greco, Alba; Lee, Peng; Maru, Dipen; Weydert, Jamie Allen; Stevens, Todd M; Brownlee, Noel A; Kemper, April E; Williams, H James; Oliverio, Brock J; Al-Agha, Osama M; Eskue, Kyle L; Newlands, Shawn D; Eltorky, Mahmoud A; Puri, Puja K; Royer, Michael C; Rush, Walter L; Tavora, Fabio; Galvin, Jeffrey R; Franks, Teri J; Carter, James Elliot; Kahn, Andrea Graciela; Lozada Muñoz, Luis R; Houghton, Dan; Land, Kevin J; Nester, Theresa; Gildea, Jacob; Lefkowitz, Jerry; Lacount, Rachel A; Thompson, Hannis W; Refaai, Majed A; Quillen, Karen; Lopez, Ana Ortega; Goldfinger, Dennis; Muram, Talia; Thompson, Hannis

2009-02-01

The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.

Manifold regularized discriminative nonnegative matrix factorization with fast gradient descent.

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Guan, Naiyang; Tao, Dacheng; Luo, Zhigang; Yuan, Bo

2011-07-01

Nonnegative matrix factorization (NMF) has become a popular data-representation method and has been widely used in image processing and pattern-recognition problems. This is because the learned bases can be interpreted as a natural parts-based representation of data and this interpretation is consistent with the psychological intuition of combining parts to form a whole. For practical classification tasks, however, NMF ignores both the local geometry of data and the discriminative information of different classes. In addition, existing research results show that the learned basis is unnecessarily parts-based because there is neither explicit nor implicit constraint to ensure the representation parts-based. In this paper, we introduce the manifold regularization and the margin maximization to NMF and obtain the manifold regularized discriminative NMF (MD-NMF) to overcome the aforementioned problems. The multiplicative update rule (MUR) can be applied to optimizing MD-NMF, but it converges slowly. In this paper, we propose a fast gradient descent (FGD) to optimize MD-NMF. FGD contains a Newton method that searches the optimal step length, and thus, FGD converges much faster than MUR. In addition, FGD includes MUR as a special case and can be applied to optimizing NMF and its variants. For a problem with 165 samples in R(1600), FGD converges in 28 s, while MUR requires 282 s. We also apply FGD in a variant of MD-NMF and experimental results confirm its efficiency. Experimental results on several face image datasets suggest the effectiveness of MD-NMF.

REVIEW ARTICLE ABSTRACT

African Journals Online (AJOL)

dell

β be a real-valued regular solution to the generalized biaxially symmetric potential equation. (. ) βα β α. ,. 2. 2. 2. 2. )1. 2(. 1. 2. F ... orthogonality of Jacobi polynomials ([1], p.8) and. Poisson Kernel ([1], p.11) to uniquely define the transform.

A System for Extracting Study Design Parameters from Nutritional Genomics Abstracts

Directory of Open Access Journals (Sweden)

Kelly Cassidy

2013-06-01

Full Text Available The extraction of study design parameters from biomedical journal articles is an important problem in natural language processing (NLP. Such parameters define the characteristics of a study, such as the duration, the number of subjects, and their profile. Here we present a system for extracting study design parameters from sentences in article abstracts. This system will be used as a component of a larger system for creating nutrigenomics networks from articles in the nutritional genomics domain. The algorithms presented consist of manually designed rules expressed either as regular expressions or in terms of sentence parse structure. A number of filters and NLP tools are also utilized within a pipelined algorithmic framework. Using this novel approach, our system performs extraction at a finer level of granularity than comparable systems, while generating results that surpass the current state of the art.

Abstract Datatypes in PVS

Science.gov (United States)

Owre, Sam; Shankar, Natarajan

1997-01-01

PVS (Prototype Verification System) is a general-purpose environment for developing specifications and proofs. This document deals primarily with the abstract datatype mechanism in PVS which generates theories containing axioms and definitions for a class of recursive datatypes. The concepts underlying the abstract datatype mechanism are illustrated using ordered binary trees as an example. Binary trees are described by a PVS abstract datatype that is parametric in its value type. The type of ordered binary trees is then presented as a subtype of binary trees where the ordering relation is also taken as a parameter. We define the operations of inserting an element into, and searching for an element in an ordered binary tree; the bulk of the report is devoted to PVS proofs of some useful properties of these operations. These proofs illustrate various approaches to proving properties of abstract datatype operations. They also describe the built-in capabilities of the PVS proof checker for simplifying abstract datatype expressions.

Orbitofrontal cortex as a cognitive map of task space.

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Wilson, Robert C; Takahashi, Yuji K; Schoenbaum, G; Niv, Yael

2014-01-22

Orbitofrontal cortex (OFC) has long been known to play an important role in decision making. However, the exact nature of that role has remained elusive. Here, we propose a unifying theory of OFC function. We hypothesize that OFC provides an abstraction of currently available information in the form of a labeling of the current task state, which is used for reinforcement learning (RL) elsewhere in the brain. This function is especially critical when task states include unobservable information, for instance, from working memory. We use this framework to explain classic findings in reversal learning, delayed alternation, extinction, and devaluation as well as more recent findings showing the effect of OFC lesions on the firing of dopaminergic neurons in ventral tegmental area (VTA) in rodents performing an RL task. In addition, we generate a number of testable experimental predictions that can distinguish our theory from other accounts of OFC function. Copyright © 2014 Elsevier Inc. All rights reserved.

The effect of episodic retrieval on inhibition in task switching.

Science.gov (United States)

Grange, James A; Kowalczyk, Agnieszka W; O'Loughlin, Rory

2017-08-01

Inhibition in task switching is inferred from n-2 repetition costs: the observation that ABA task switching sequences are responded to slower than CBA sequences. This is thought to reflect the persisting inhibition of Task A, which slows reactivation attempts. Mayr (2002) reported an experiment testing a critical noninhibitory account of this effect, namely episodic retrieval: If the trial parameters for Task A match across an ABA sequence, responses should be facilitated because of priming from episodic retrieval; a cost would occur if trial parameters mismatch. In a rule-switching paradigm, Mayr reported no significant difference in n-2 repetition cost when the trial parameters repeated or switched across an ABA sequence, in clear contrast to the episodic retrieval account. What remains unclear is whether successful episodic retrieval modulates the n-2 repetition cost. Across 3 experiments-including a close replication of Mayr-we find clear evidence of reduced n-2 task repetition costs when episodic retrieval is controlled. We find that the effect of episodic retrieval on the n-2 task repetition cost is increased when the cue-task relationship is made more abstract, suggesting the effect is because of interference in establishing the relevant attentional set. We also demonstrate that the episodic retrieval effect is not influenced by retrieval of low-level, perceptual, elements. Together, the data suggest the n-2 task repetition cost-typically attributable to an inhibitory mechanism-also reflects episodic retrieval effects. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Bounded Perturbation Regularization for Linear Least Squares Estimation

KAUST Repository

Ballal, Tarig

2017-10-18

This paper addresses the problem of selecting the regularization parameter for linear least-squares estimation. We propose a new technique called bounded perturbation regularization (BPR). In the proposed BPR method, a perturbation with a bounded norm is allowed into the linear transformation matrix to improve the singular-value structure. Following this, the problem is formulated as a min-max optimization problem. Next, the min-max problem is converted to an equivalent minimization problem to estimate the unknown vector quantity. The solution of the minimization problem is shown to converge to that of the ℓ2 -regularized least squares problem, with the unknown regularizer related to the norm bound of the introduced perturbation through a nonlinear constraint. A procedure is proposed that combines the constraint equation with the mean squared error (MSE) criterion to develop an approximately optimal regularization parameter selection algorithm. Both direct and indirect applications of the proposed method are considered. Comparisons with different Tikhonov regularization parameter selection methods, as well as with other relevant methods, are carried out. Numerical results demonstrate that the proposed method provides significant improvement over state-of-the-art methods.

Heuristics in Managing Complex Clinical Decision Tasks in Experts' Decision Making.

Science.gov (United States)

Islam, Roosan; Weir, Charlene; Del Fiol, Guilherme

2014-09-01

Clinical decision support is a tool to help experts make optimal and efficient decisions. However, little is known about the high level of abstractions in the thinking process for the experts. The objective of the study is to understand how clinicians manage complexity while dealing with complex clinical decision tasks. After approval from the Institutional Review Board (IRB), three clinical experts were interviewed the transcripts from these interviews were analyzed. We found five broad categories of strategies by experts for managing complex clinical decision tasks: decision conflict, mental projection, decision trade-offs, managing uncertainty and generating rule of thumb. Complexity is created by decision conflicts, mental projection, limited options and treatment uncertainty. Experts cope with complexity in a variety of ways, including using efficient and fast decision strategies to simplify complex decision tasks, mentally simulating outcomes and focusing on only the most relevant information. Understanding complex decision making processes can help design allocation based on the complexity of task for clinical decision support design.

Psychological effects and epistemological education through mathematics "abstraction" and "construction"

Directory of Open Access Journals (Sweden)

Aurel Pera

2015-10-01

Full Text Available This study is part of a broader research which will be found in future work, Psychology and epistemology of mathematical creation, complementary work of experimental research psychology mathematics, whose investigative approach, promoting the combination type cross section paradigms and quantitative methods and qualitative and comparative method and the analytic-synthetic, based on the following idea: to make learning as efficient, contents and methods must be appropriate to the individual particularities of the pupils, a measure of the balance between converging and diverging dosing tasks as a promising opening to the transition from education proficiency in math performance. At this juncture, mathematical existence as ontological approach against the background of a history of "abstraction" mathematical and theoretical observations on the abstraction, realization and other mathematical thought processes, explanatory approach fulfills the context in which s mathematics constituted an important factor in psychological and methodological perspective, in a context of maximizing the educational effectiveness that depends on the quality of the methods used in teaching, focused on knowledge of the general principles of psycho-didactics not only mathematical and mental organization individual student or knowledge of the factors that make possible psycho-educational learning process.

Manifold Regularized Experimental Design for Active Learning.

Science.gov (United States)

Zhang, Lining; Shum, Hubert P H; Shao, Ling

2016-12-02

Various machine learning and data mining tasks in classification require abundant data samples to be labeled for training. Conventional active learning methods aim at labeling the most informative samples for alleviating the labor of the user. Many previous studies in active learning select one sample after another in a greedy manner. However, this is not very effective because the classification models has to be retrained for each newly labeled sample. Moreover, many popular active learning approaches utilize the most uncertain samples by leveraging the classification hyperplane of the classifier, which is not appropriate since the classification hyperplane is inaccurate when the training data are small-sized. The problem of insufficient training data in real-world systems limits the potential applications of these approaches. This paper presents a novel method of active learning called manifold regularized experimental design (MRED), which can label multiple informative samples at one time for training. In addition, MRED gives an explicit geometric explanation for the selected samples to be labeled by the user. Different from existing active learning methods, our method avoids the intrinsic problems caused by insufficiently labeled samples in real-world applications. Various experiments on synthetic datasets, the Yale face database and the Corel image database have been carried out to show how MRED outperforms existing methods.

MRI reconstruction with joint global regularization and transform learning.

Science.gov (United States)

Tanc, A Korhan; Eksioglu, Ender M

2016-10-01

Sparsity based regularization has been a popular approach to remedy the measurement scarcity in image reconstruction. Recently, sparsifying transforms learned from image patches have been utilized as an effective regularizer for the Magnetic Resonance Imaging (MRI) reconstruction. Here, we infuse additional global regularization terms to the patch-based transform learning. We develop an algorithm to solve the resulting novel cost function, which includes both patchwise and global regularization terms. Extensive simulation results indicate that the introduced mixed approach has improved MRI reconstruction performance, when compared to the algorithms which use either of the patchwise transform learning or global regularization terms alone. Copyright © 2016 Elsevier Ltd. All rights reserved.

Allograph priming is based on abstract letter identities: Evidence from Japanese kana.

Science.gov (United States)

Kinoshita, Sachiko; Schubert, Teresa; Verdonschot, Rinus G

2018-04-23

It is well-established that allographs like the uppercase and lowercase forms of the Roman alphabet (e.g., a and A) map onto the same "abstract letter identity," orthographic representations that are independent of the visual form. Consistent with this, in the allograph match task ("Are 'a' and 'A' the same letter?"), priming by a masked letter prime is equally robust for visually dissimilar prime-target pairs (e.g., d and D) and similar pairs (e.g., c and C). However, in principle this pattern of priming is also consistent with the possibility that allograph priming is purely phonological, based on the letter name. Because different allographic forms of the same letter, by definition, share a letter name, it is impossible to rule out this possibility a priori. In the present study, we investigated the influence of shared letter names by taking advantage of the fact that Japanese is written in two distinct writing systems, syllabic kana-that has two parallel forms, hiragana and katakana-and logographic kanji. Using the allograph match task, we tested whether a kanji prime with the same pronunciation as the target kana (e.g., - い, both pronounced /i/) produces the same amount of priming as a kana prime in the opposite kana form (e.g., イ- い). We found that the kana primes produced substantially greater priming than the phonologically identical kanji prime, which we take as evidence that allograph priming is based on abstract kana identity, not purely phonology. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Strictly-regular number system and data structures

DEFF Research Database (Denmark)

Elmasry, Amr Ahmed Abd Elmoneim; Jensen, Claus; Katajainen, Jyrki

2010-01-01

We introduce a new number system that we call the strictly-regular system, which efficiently supports the operations: digit-increment, digit-decrement, cut, concatenate, and add. Compared to other number systems, the strictly-regular system has distinguishable properties. It is superior to the re...

Analysis of regularized Navier-Stokes equations, 2

Science.gov (United States)

Ou, Yuh-Roung; Sritharan, S. S.

1989-01-01

A practically important regularization of the Navier-Stokes equations was analyzed. As a continuation of the previous work, the structure of the attractors characterizing the solutins was studied. Local as well as global invariant manifolds were found. Regularity properties of these manifolds are analyzed.

Regularities, Natural Patterns and Laws of Nature

Directory of Open Access Journals (Sweden)

Stathis Psillos

2014-02-01

Full Text Available  The goal of this paper is to sketch an empiricist metaphysics of laws of nature. The key idea is that there are regularities without regularity-enforcers. Differently put, there are natural laws without law-makers of a distinct metaphysical kind. This sketch will rely on the concept of a natural pattern and more significantly on the existence of a network of natural patterns in nature. The relation between a regularity and a pattern will be analysed in terms of mereology.  Here is the road map. In section 2, I will briefly discuss the relation between empiricism and metaphysics, aiming to show that an empiricist metaphysics is possible. In section 3, I will offer arguments against stronger metaphysical views of laws. Then, in section 4 I will motivate nomic objectivism. In section 5, I will address the question ‘what is a regularity?’ and will develop a novel answer to it, based on the notion of a natural pattern. In section 6, I will raise the question: ‘what is a law of nature?’, the answer to which will be: a law of nature is a regularity that is characterised by the unity of a natural pattern.

The auditory dynamic attending theory revisited: A closer look at the pitch comparison task.

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Bauer, Anna-Katharina R; Jaeger, Manuela; Thorne, Jeremy D; Bendixen, Alexandra; Debener, Stefan

2015-11-11

The dynamic attending theory as originally proposed by Jones, 1976. Psychol. Rev. 83(5), 323-355 posits that tone sequences presented at a regular rhythm entrain attentional oscillations and thereby facilitate the processing of sounds presented in phase with this rhythm. The increased interest in neural correlates of dynamic attending requires robust behavioral indicators of the phenomenon. Here we aimed to replicate and complement the most prominent experimental implementation of dynamic attending (Jones et al., 2002. Psychol. Sci. 13(4), 313-319). The paradigm uses a pitch comparison task in which two tones, the initial and the last of a longer series, have to be compared. In-between the two, distractor tones with variable pitch are presented, at a regular pace. A comparison tone presented in phase with the entrained rhythm is hypothesized to lead to better behavioral performance. Aiming for a conceptual replication, four different variations of the original paradigm were created which were followed by an exact replication attempt. Across all five experiments, only 40 of the 140 tested participants showed the hypothesized pattern of an inverted U-shaped profile in task accuracy, and the group average effects did not replicate the pattern reported by Jones et al., 2002. Psychol. Sci. 13(4), 313-319 in any of the five experiments. However, clear evidence for a relationship between musicality and overall behavioral performance was found. This study casts doubt on the suitability of the pitch comparison task for demonstrating auditory dynamic attending. We discuss alternative tasks that have been shown to support dynamic attending theory, thus lending themselves more readily to studying its neural correlates. This article is part of a Special Issue entitled SI: Prediction and Attention. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Consistent Partial Least Squares Path Modeling via Regularization.

Science.gov (United States)

Jung, Sunho; Park, JaeHong

2018-01-01

Partial least squares (PLS) path modeling is a component-based structural equation modeling that has been adopted in social and psychological research due to its data-analytic capability and flexibility. A recent methodological advance is consistent PLS (PLSc), designed to produce consistent estimates of path coefficients in structural models involving common factors. In practice, however, PLSc may frequently encounter multicollinearity in part because it takes a strategy of estimating path coefficients based on consistent correlations among independent latent variables. PLSc has yet no remedy for this multicollinearity problem, which can cause loss of statistical power and accuracy in parameter estimation. Thus, a ridge type of regularization is incorporated into PLSc, creating a new technique called regularized PLSc. A comprehensive simulation study is conducted to evaluate the performance of regularized PLSc as compared to its non-regularized counterpart in terms of power and accuracy. The results show that our regularized PLSc is recommended for use when serious multicollinearity is present.

Consistent Partial Least Squares Path Modeling via Regularization

Directory of Open Access Journals (Sweden)

Sunho Jung

2018-02-01

Full Text Available Partial least squares (PLS path modeling is a component-based structural equation modeling that has been adopted in social and psychological research due to its data-analytic capability and flexibility. A recent methodological advance is consistent PLS (PLSc, designed to produce consistent estimates of path coefficients in structural models involving common factors. In practice, however, PLSc may frequently encounter multicollinearity in part because it takes a strategy of estimating path coefficients based on consistent correlations among independent latent variables. PLSc has yet no remedy for this multicollinearity problem, which can cause loss of statistical power and accuracy in parameter estimation. Thus, a ridge type of regularization is incorporated into PLSc, creating a new technique called regularized PLSc. A comprehensive simulation study is conducted to evaluate the performance of regularized PLSc as compared to its non-regularized counterpart in terms of power and accuracy. The results show that our regularized PLSc is recommended for use when serious multicollinearity is present.

Assessing Task Migration Impact on Embedded Soft Real-Time Streaming Multimedia Applications

Directory of Open Access Journals (Sweden)

Alimonda Andrea

2008-01-01

Full Text Available Abstract Multiprocessor systems on chips (MPSoCs are envisioned as the future of embedded platforms such as game-engines, smart-phones and palmtop computers. One of the main challenge preventing the widespread diffusion of these systems is the efficient mapping of multitask multimedia applications on processing elements. Dynamic solutions based on task migration has been recently explored to perform run-time reallocation of task to maximize performance and optimize energy consumption. Even if task migration can provide high flexibility, its overhead must be carefully evaluated when applied to soft real-time applications. In fact, these applications impose deadlines that may be missed during the migration process. In this paper we first present a middleware infrastructure supporting dynamic task allocation for NUMA architectures. Then we perform an extensive characterization of its impact on multimedia soft real-time applications using a software FM Radio benchmark.

Regularization of the Boundary-Saddle-Node Bifurcation

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Xia Liu

2018-01-01

Full Text Available In this paper we treat a particular class of planar Filippov systems which consist of two smooth systems that are separated by a discontinuity boundary. In such systems one vector field undergoes a saddle-node bifurcation while the other vector field is transversal to the boundary. The boundary-saddle-node (BSN bifurcation occurs at a critical value when the saddle-node point is located on the discontinuity boundary. We derive a local topological normal form for the BSN bifurcation and study its local dynamics by applying the classical Filippov’s convex method and a novel regularization approach. In fact, by the regularization approach a given Filippov system is approximated by a piecewise-smooth continuous system. Moreover, the regularization process produces a singular perturbation problem where the original discontinuous set becomes a center manifold. Thus, the regularization enables us to make use of the established theories for continuous systems and slow-fast systems to study the local behavior around the BSN bifurcation.

Scapular kinematics and muscle activities during pushing tasks.

Science.gov (United States)

Huang, Chun-Kai; Siu, Ka-Chun; Lien, Hen-Yu; Lee, Yun-Ju; Lin, Yang-Hua

2013-01-01

Pushing tasks are functional activities of daily living. However, shoulder complaints exist among workers exposed to regular pushing conditions. It is crucial to investigate the control of shoulder girdles during pushing tasks. The objective of the study was to demonstrate scapular muscle activities and motions on the dominant side during pushing tasks and the relationship between scapular kinematics and muscle activities in different pushing conditions. Thirty healthy adults were recruited to push a four-wheel cart in six pushing conditions. The electromyographic signals of the upper trapezius (UT) and serratus anterior (SA) muscles were recorded. A video-based system was used for measuring the movement of the shoulder girdle and scapular kinematics. Differences in scapular kinematics and muscle activities due to the effects of handle heights and weights of the cart were analyzed using two-way ANOVA with repeated measures. The relationships between scapular kinematics and muscle activities were examined by Pearson's correlation coefficients. The changes in upper trapezius and serratus anterior muscle activities increased significantly with increased pushing weights in the one-step pushing phase. The UT/SA ratio on the dominant side decreases significantly with increased handle heights in the one-step pushing phase. The changes in upward rotation, lateral slide and elevation of the scapula decreased with increased pushing loads in the trunk-forward pushing phase. This study indicated that increased pushing loads result in decreased motions of upward rotation, lateral slide and elevation of the scapula; decreased handle heights result in relatively increased activities of the serratus anterior muscles during pushing tasks.

Low-Complexity Regularization Algorithms for Image Deblurring

KAUST Repository

Alanazi, Abdulrahman

2016-11-01

Image restoration problems deal with images in which information has been degraded by blur or noise. In practice, the blur is usually caused by atmospheric turbulence, motion, camera shake, and several other mechanical or physical processes. In this study, we present two regularization algorithms for the image deblurring problem. We first present a new method based on solving a regularized least-squares (RLS) problem. This method is proposed to find a near-optimal value of the regularization parameter in the RLS problems. Experimental results on the non-blind image deblurring problem are presented. In all experiments, comparisons are made with three benchmark methods. The results demonstrate that the proposed method clearly outperforms the other methods in terms of both the output PSNR and structural similarity, as well as the visual quality of the deblurred images. To reduce the complexity of the proposed algorithm, we propose a technique based on the bootstrap method to estimate the regularization parameter in low and high-resolution images. Numerical results show that the proposed technique can effectively reduce the computational complexity of the proposed algorithms. In addition, for some cases where the point spread function (PSF) is separable, we propose using a Kronecker product so as to reduce the computations. Furthermore, in the case where the image is smooth, it is always desirable to replace the regularization term in the RLS problems by a total variation term. Therefore, we propose a novel method for adaptively selecting the regularization parameter in a so-called square root regularized total variation (SRTV). Experimental results demonstrate that our proposed method outperforms the other benchmark methods when applied to smooth images in terms of PSNR, SSIM and the restored image quality. In this thesis, we focus on the non-blind image deblurring problem, where the blur kernel is assumed to be known. However, we developed algorithms that also work

Improvements in GRACE Gravity Fields Using Regularization

Science.gov (United States)

Save, H.; Bettadpur, S.; Tapley, B. D.

2008-12-01

The unconstrained global gravity field models derived from GRACE are susceptible to systematic errors that show up as broad "stripes" aligned in a North-South direction on the global maps of mass flux. These errors are believed to be a consequence of both systematic and random errors in the data that are amplified by the nature of the gravity field inverse problem. These errors impede scientific exploitation of the GRACE data products, and limit the realizable spatial resolution of the GRACE global gravity fields in certain regions. We use regularization techniques to reduce these "stripe" errors in the gravity field products. The regularization criteria are designed such that there is no attenuation of the signal and that the solutions fit the observations as well as an unconstrained solution. We have used a computationally inexpensive method, normally referred to as "L-ribbon", to find the regularization parameter. This paper discusses the characteristics and statistics of a 5-year time-series of regularized gravity field solutions. The solutions show markedly reduced stripes, are of uniformly good quality over time, and leave little or no systematic observation residuals, which is a frequent consequence of signal suppression from regularization. Up to degree 14, the signal in regularized solution shows correlation greater than 0.8 with the un-regularized CSR Release-04 solutions. Signals from large-amplitude and small-spatial extent events - such as the Great Sumatra Andaman Earthquake of 2004 - are visible in the global solutions without using special post-facto error reduction techniques employed previously in the literature. Hydrological signals as small as 5 cm water-layer equivalent in the small river basins, like Indus and Nile for example, are clearly evident, in contrast to noisy estimates from RL04. The residual variability over the oceans relative to a seasonal fit is small except at higher latitudes, and is evident without the need for de-striping or

Illusory control, gambling, and video gaming: an investigation of regular gamblers and video game players.

Science.gov (United States)

King, Daniel L; Ejova, Anastasia; Delfabbro, Paul H

2012-09-01

There is a paucity of empirical research examining the possible association between gambling and video game play. In two studies, we examined the association between video game playing, erroneous gambling cognitions, and risky gambling behaviour. One hundred and fifteen participants, including 65 electronic gambling machine (EGM) players and 50 regular video game players, were administered a questionnaire that examined video game play, gambling involvement, problem gambling, and beliefs about gambling. We then assessed each groups' performance on a computerised gambling task that involved real money. A post-game survey examined perceptions of the skill and chance involved in the gambling task. The results showed that video game playing itself was not significantly associated with gambling involvement or problem gambling status. However, among those persons who both gambled and played video games, video game playing was uniquely and significantly positively associated with the perception of direct control over chance-based gambling events. Further research is needed to better understand the nature of this association, as it may assist in understanding the impact of emerging digital gambling technologies.

Deterministic automata for extended regular expressions

Directory of Open Access Journals (Sweden)

Syzdykov Mirzakhmet

2017-12-01

Full Text Available In this work we present the algorithms to produce deterministic finite automaton (DFA for extended operators in regular expressions like intersection, subtraction and complement. The method like “overriding” of the source NFA(NFA not defined with subset construction rules is used. The past work described only the algorithm for AND-operator (or intersection of regular languages; in this paper the construction for the MINUS-operator (and complement is shown.

Regularities of intermediate adsorption complex relaxation

International Nuclear Information System (INIS)

Manukova, L.A.

1982-01-01

The experimental data, characterizing the regularities of intermediate adsorption complex relaxation in the polycrystalline Mo-N 2 system at 77 K are given. The method of molecular beam has been used in the investigation. The analytical expressions of change regularity in the relaxation process of full and specific rates - of transition from intermediate state into ''non-reversible'', of desorption into the gas phase and accumUlation of the particles in the intermediate state are obtained

Use of a task-oriented self-instruction method to support children in primary school with poor handwriting quality and speed

NARCIS (Netherlands)

Jongmans, M.J.; Linthorst-Bakker, E.; Westenberg, Y.; Smits-Engelsman, B.C.M.

2003-01-01

Two studies were conducted to investigate the effect of a task-specific self-instruction intervention to improve handwriting ability of children with poor handwriting quality in schools for regular education (Study 1) and children with poor handwriting quality in schools for special education (Study

Sparse structure regularized ranking

KAUST Repository

Wang, Jim Jing-Yan; Sun, Yijun; Gao, Xin

2014-01-01

Learning ranking scores is critical for the multimedia database retrieval problem. In this paper, we propose a novel ranking score learning algorithm by exploring the sparse structure and using it to regularize ranking scores. To explore the sparse

Sparse structure regularized ranking

KAUST Repository

Wang, Jim Jing-Yan

2014-04-17

Learning ranking scores is critical for the multimedia database retrieval problem. In this paper, we propose a novel ranking score learning algorithm by exploring the sparse structure and using it to regularize ranking scores. To explore the sparse structure, we assume that each multimedia object could be represented as a sparse linear combination of all other objects, and combination coefficients are regarded as a similarity measure between objects and used to regularize their ranking scores. Moreover, we propose to learn the sparse combination coefficients and the ranking scores simultaneously. A unified objective function is constructed with regard to both the combination coefficients and the ranking scores, and is optimized by an iterative algorithm. Experiments on two multimedia database retrieval data sets demonstrate the significant improvements of the propose algorithm over state-of-the-art ranking score learning algorithms.

20 CFR 226.35 - Deductions from regular annuity rate.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Deductions from regular annuity rate. 226.35... COMPUTING EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Computing a Spouse or Divorced Spouse Annuity § 226.35 Deductions from regular annuity rate. The regular annuity rate of the spouse and divorced...

Effectiveness of Focus-on-Forms Instruction: Different Outcomes on Constrained- and Free-Production Tasks?

Directory of Open Access Journals (Sweden)

Giselle Corbeil

2005-06-01

Full Text Available Abstract The purpose of this study is to investigate how focus-on-forms instruction in second language teaching affects attention to forms in two different types of task: constrained and free production. These two different types of task were administered to 87 university students enrolled in a first-year French as a second language course before and after instruction on qualifying adjective agreement. Comparisons were made between learning-gain differences from pre- to post-tests for both tasks. Significant differences between pre- and post-test scores were found for both tasks. Although the difference between the two tasks was not significant, the learning-gain difference was somewhat higher for the constrained-production task than for the free-production task. When the total number of adjectives used in the compositions was broken down into colour adjectives and non-colour adjectives, no significant learning gains were observed between the two categories, although the learning gains for the non-colour adjectives was twice as high as for the colour adjectives. Possible explanations for these results are discussed.

Abstraction and art.

Science.gov (United States)

Gortais, Bernard

2003-07-29

In a given social context, artistic creation comprises a set of processes, which relate to the activity of the artist and the activity of the spectator. Through these processes we see and understand that the world is vaster than it is said to be. Artistic processes are mediated experiences that open up the world. A successful work of art expresses a reality beyond actual reality: it suggests an unknown world using the means and the signs of the known world. Artistic practices incorporate the means of creation developed by science and technology and change forms as they change. Artists and the public follow different processes of abstraction at different levels, in the definition of the means of creation, of representation and of perception of a work of art. This paper examines how the processes of abstraction are used within the framework of the visual arts and abstract painting, which appeared during a period of growing importance for the processes of abstraction in science and technology, at the beginning of the twentieth century. The development of digital platforms and new man-machine interfaces allow multimedia creations. This is performed under the constraint of phases of multidisciplinary conceptualization using generic representation languages, which tend to abolish traditional frontiers between the arts: visual arts, drama, dance and music.

Regularization theory for ill-posed problems selected topics

CERN Document Server

Lu, Shuai

2013-01-01

Thismonograph is a valuable contribution to thehighly topical and extremly productive field ofregularisationmethods for inverse and ill-posed problems. The author is an internationally outstanding and acceptedmathematicianin this field. In his book he offers a well-balanced mixtureof basic and innovative aspects.He demonstrates new,differentiatedviewpoints, and important examples for applications. The bookdemontrates thecurrent developments inthe field of regularization theory,such as multiparameter regularization and regularization in learning theory. The book is written for graduate and PhDs

20 CFR 226.34 - Divorced spouse regular annuity rate.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Divorced spouse regular annuity rate. 226.34... COMPUTING EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Computing a Spouse or Divorced Spouse Annuity § 226.34 Divorced spouse regular annuity rate. The regular annuity rate of a divorced spouse is equal to...

Chimeric mitochondrial peptides from contiguous regular and swinger RNA.

Science.gov (United States)

Seligmann, Hervé

2016-01-01

Previous mass spectrometry analyses described human mitochondrial peptides entirely translated from swinger RNAs, RNAs where polymerization systematically exchanged nucleotides. Exchanges follow one among 23 bijective transformation rules, nine symmetric exchanges (X ↔ Y, e.g. A ↔ C) and fourteen asymmetric exchanges (X → Y → Z → X, e.g. A → C → G → A), multiplying by 24 DNA's protein coding potential. Abrupt switches from regular to swinger polymerization produce chimeric RNAs. Here, human mitochondrial proteomic analyses assuming abrupt switches between regular and swinger transcriptions, detect chimeric peptides, encoded by part regular, part swinger RNA. Contiguous regular- and swinger-encoded residues within single peptides are stronger evidence for translation of swinger RNA than previously detected, entirely swinger-encoded peptides: regular parts are positive controls matched with contiguous swinger parts, increasing confidence in results. Chimeric peptides are 200 × rarer than swinger peptides (3/100,000 versus 6/1000). Among 186 peptides with > 8 residues for each regular and swinger parts, regular parts of eleven chimeric peptides correspond to six among the thirteen recognized, mitochondrial protein-coding genes. Chimeric peptides matching partly regular proteins are rarer and less expressed than chimeric peptides matching non-coding sequences, suggesting targeted degradation of misfolded proteins. Present results strengthen hypotheses that the short mitogenome encodes far more proteins than hitherto assumed. Entirely swinger-encoded proteins could exist.

Recently learned foreign abstract and concrete nouns are represented in distinct cortical networks similar to the native language.

Science.gov (United States)

Mayer, Katja M; Macedonia, Manuela; von Kriegstein, Katharina

2017-09-01

In the native language, abstract and concrete nouns are represented in distinct areas of the cerebral cortex. Currently, it is unknown whether this is also the case for abstract and concrete nouns of a foreign language. Here, we taught adult native speakers of German 45 abstract and 45 concrete nouns of a foreign language. After learning the nouns for 5 days, participants performed a vocabulary translation task during functional magnetic resonance imaging. Translating abstract nouns in contrast to concrete nouns elicited responses in regions that are also responsive to abstract nouns in the native language: the left inferior frontal gyrus and the left middle and superior temporal gyri. Concrete nouns elicited larger responses in the angular gyri bilaterally and the left parahippocampal gyrus than abstract nouns. The cluster in the left angular gyrus showed psychophysiological interaction (PPI) with the left lingual gyrus. The left parahippocampal gyrus showed PPI with the posterior cingulate cortex. Similar regions have been previously found for concrete nouns in the native language. The results reveal similarities in the cortical representation of foreign language nouns with the representation of native language nouns that already occur after 5 days of vocabulary learning. Furthermore, we showed that verbal and enriched learning methods were equally suitable to teach foreign abstract and concrete nouns. Hum Brain Mapp 38:4398-4412, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Two castes sizes of leafcutter ants in task partitioning in foraging activity

Directory of Open Access Journals (Sweden)

Marcelo Arruda de Toledo

Full Text Available ABSTRACT: Task partitioning in eusocial animals is most likely an evolutionary adaptation that optimizes the efficiency of the colony to grow and reproduce. It was investigated indirect task partitioning in two castes sizes; this involves task partitioning in which the material transported is not transferred directly from one individual to another, but where it is dropped by one ant to be picked up by another. In two separate approaches, it was confirmed previous results pertaining to leaf caching activities among Atta colombica with task partitioning activities involving leaf dropping among Atta sexdens rubropilosa , in which there is a correlation between the size of an individual ant and the leaf fragment it transports. It was also suggested that this correlation exists only in individual ants that cut and transport (CaT the same fragment to the nest. When task partitioning occurs and individual ants transporting (T leaf fragments cut by other ants, the correlation becomes looser or disappears. We also observed that CaT ants are smaller than T ants.

The Impact of Task-Based Instruction Program on Fostering ESL Learners’ Speaking Ability: A Cognitive Approach

Directory of Open Access Journals (Sweden)

Mohammad Mohammadipour

2015-04-01

Full Text Available Adopting a direct approach to contrive sufficient focus on form (accuracy would facilitate interlanguage development without decreasing the naturalness of communication that communicative tasks can generate. This study aimed to determine the effectiveness of a proposed task-based instruction programme within a cognitive approach in fostering overall speaking proficiency of undergraduate students. 72 students from several public universities participated in the study, which employed an experimental design. The students of the experimental group received training through the proposed task-based instruction programme for three months while those in the control group received regular instruction. The preliminary English Test (PET was administered as a pre- and post-test measure of speaking proficiency. Findings of the study showed a significant improvement in the overall speaking proficiency of the students who were exposed to the proposed programme.  The findings suggest the potential of the task-based programme in enhancing undergraduate students' overall speaking proficiency. Keywords: The cognitive approach, speaking skills, task based instruction, TESL, the communicative approach

Fast and compact regular expression matching

DEFF Research Database (Denmark)

Bille, Philip; Farach-Colton, Martin

2008-01-01

We study 4 problems in string matching, namely, regular expression matching, approximate regular expression matching, string edit distance, and subsequence indexing, on a standard word RAM model of computation that allows logarithmic-sized words to be manipulated in constant time. We show how...... to improve the space and/or remove a dependency on the alphabet size for each problem using either an improved tabulation technique of an existing algorithm or by combining known algorithms in a new way....

Dimensional regularization and analytical continuation at finite temperature

International Nuclear Information System (INIS)

Chen Xiangjun; Liu Lianshou

1998-01-01

The relationship between dimensional regularization and analytical continuation of infrared divergent integrals at finite temperature is discussed and a method of regularization of infrared divergent integrals and infrared divergent sums is given

Relationship between Usefulness Assessments and Perceptions of Work Task Complexity and Search Topic Specificity: An Exploratory Study

DEFF Research Database (Denmark)

Ingwersen, Peter; Wang, Peiling

2012-01-01

This research investigates the relations between the usefulness assessments of retrieved documents and the perceptions of task complexity and search topic specificity. Twenty-three academic researchers submitted 65 real task-based information search topics. These task topics were searched...... in an integrated document collection consisting of full text research articles in PDFs, abstracts, and bibliographic records (the iSearch Test Collection in Physics). The search results were provided to the researchers who, as task performers, made assessments of usefulness using a four-point sale (highly, fairly......, marginally, or not useful). In addition, they also assessed the perceived task complexity (highly, fairly, and routine/low) and the perceived specificity of the search topic (highly, fairly, and generic/low). It is found that highly specific topics associate with all degrees of task complexity, whereas...

International Energy Agency Ocean Energy Systems Task 10 Wave Energy Converter Modeling Verification and Validation: Preprint

Energy Technology Data Exchange (ETDEWEB)

Wendt, Fabian F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Yu, Yi-Hsiang [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Nielsen, Kim [Ramboll, Copenhagen (Denmark); Ruehl, Kelley [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bunnik, Tim [MARIN (Netherlands); Touzon, Imanol [Tecnalia (Spain); Nam, Bo Woo [KRISO (Korea, Rep. of); Kim, Jeong Seok [KRISO (Korea, Rep. of); Janson, Carl Erik [Chalmers University (Sweden); Jakobsen, Ken-Robert [EDRMedeso (Norway); Crowley, Sarah [WavEC (Portugal); Vega, Luis [Hawaii Natural Energy Institute (United States); Rajagopalan, Krishnakimar [Hawaii Natural Energy Institute (United States); Mathai, Thomas [Glosten (United States); Greaves, Deborah [Plymouth University (United Kingdom); Ransley, Edward [Plymouth University (United Kingdom); Lamont-Kane, Paul [Queen' s University Belfast (United Kingdom); Sheng, Wanan [University College Cork (Ireland); Costello, Ronan [Wave Venture (United Kingdom); Kennedy, Ben [Wave Venture (United Kingdom); Thomas, Sarah [Floating Power Plant (Denmark); Heras, Pilar [Floating Power Plant (Denmark); Bingham, Harry [Technical University of Denmark (Denmark); Kurniawan, Adi [Aalborg University (Denmark); Kramer, Morten Mejlhede [Aalborg University (Denmark); Ogden, David [INNOSEA (France); Girardin, Samuel [INNOSEA (France); Babarit, Aurelien [EC Nantes (France); Wuillaume, Pierre-Yves [EC Nantes (France); Steinke, Dean [Dynamic Systems Analysis (Canada); Roy, Andre [Dynamic Systems Analysis (Canada); Beatty, Scott [Cascadia Coast Research (Canada); Schofield, Paul [ANSYS (United States); Kim, Kyong-Hwan [KRISO (Korea, Rep. of); Jansson, Johan [KTH Royal Inst. of Technology, Stockholm (Sweden); BCAM (Spain); Hoffman, Johan [KTH Royal Inst. of Technology, Stockholm (Sweden)

2017-10-16

This is the first joint reference paper for the Ocean Energy Systems (OES) Task 10 Wave Energy Converter modeling verification and validation group. The group is established under the OES Energy Technology Network program under the International Energy Agency. OES was founded in 2001 and Task 10 was proposed by Bob Thresher (National Renewable Energy Laboratory) in 2015 and approved by the OES Executive Committee EXCO in 2016. The kickoff workshop took place in September 2016, wherein the initial baseline task was defined. Experience from similar offshore wind validation/verification projects (OC3-OC5 conducted within the International Energy Agency Wind Task 30) [1], [2] showed that a simple test case would help the initial cooperation to present results in a comparable way. A heaving sphere was chosen as the first test case. The team of project participants simulated different numerical experiments, such as heave decay tests and regular and irregular wave cases. The simulation results are presented and discussed in this paper.

Completeness of Lyapunov Abstraction

DEFF Research Database (Denmark)

Wisniewski, Rafal; Sloth, Christoffer

2013-01-01

the vector field, which allows the generation of a complete abstraction. To compute the functions that define the subdivision of the state space in an algorithm, we formulate a sum of squares optimization problem. This optimization problem finds the best subdivisioning functions, with respect to the ability......This paper addresses the generation of complete abstractions of polynomial dynamical systems by timed automata. For the proposed abstraction, the state space is divided into cells by sublevel sets of functions. We identify a relation between these functions and their directional derivatives along...

Regular and conformal regular cores for static and rotating solutions

Energy Technology Data Exchange (ETDEWEB)

Azreg-Aïnou, Mustapha

2014-03-07

Using a new metric for generating rotating solutions, we derive in a general fashion the solution of an imperfect fluid and that of its conformal homolog. We discuss the conditions that the stress–energy tensors and invariant scalars be regular. On classical physical grounds, it is stressed that conformal fluids used as cores for static or rotating solutions are exempt from any malicious behavior in that they are finite and defined everywhere.

Regular and conformal regular cores for static and rotating solutions

International Nuclear Information System (INIS)

Azreg-Aïnou, Mustapha

2014-01-01

Using a new metric for generating rotating solutions, we derive in a general fashion the solution of an imperfect fluid and that of its conformal homolog. We discuss the conditions that the stress–energy tensors and invariant scalars be regular. On classical physical grounds, it is stressed that conformal fluids used as cores for static or rotating solutions are exempt from any malicious behavior in that they are finite and defined everywhere.

Associations Between Driving Performance and Engaging in Secondary Tasks: A Systematic Review

Science.gov (United States)

Ferdinand, Alva O.

2014-01-01

We conducted a systematic review and meta-analysis of the literature examining the relationship between driving performance and engaging in secondary tasks. We extracted data from abstracts of 206 empirical articles published between 1968 and 2012 and developed a logistic regression model to identify correlates of a detrimental relationship between secondary tasks and driving performance. Of 350 analyses, 80% reported finding a detrimental relationship. Studies using experimental designs were 37% less likely to report a detrimental relationship (P = .014). Studies examining mobile phone use while driving were 16% more likely to find such a relationship (P = .009). Quasi-experiments can better determine the effects of secondary tasks on driving performance and consequently serve to inform policymakers interested in reducing distracted driving and increasing roadway safety. PMID:24432925

Examining the Effect of Interference on Short-term Memory Recall of Arabic Abstract and Concrete Words Using Free, Cued, and Serial Recall Paradigms

OpenAIRE

Ahmed Mohammed Saleh Alduais; Yasir Saad Almukhaizeem

2015-01-01

Purpose: To see if there is a correlation between interference and short-term memory recall and to examine interference as a factor affecting memory recalling of Arabic and abstract words through free, cued, and serial recall tasks. Method: Four groups of undergraduates in King Saud University, Saudi Arabia participated in this study. The first group consisted of 9 undergraduates who were trained to perform three types of recall for 20 Arabic abstract and concrete words. The second, third and...

REGULAR REHEARSAL HELPS IN CONSOLIDATION OF LONG TERM MEMORY

Directory of Open Access Journals (Sweden)

Milind Parle

2006-03-01

Full Text Available Memory, one of the most complex functions of the brain comprises of multiple components such as perception, registration, consolidation, storage, retrieval and decay. The present study was undertaken to evaluate the impact of different training sessions on the retention capacity of rats. The capacity of retention of learnt task was measured using exteroceptive behavioral models such as Hexagonal swimming pool apparatus, Hebb-Williams maze and Elevated plus-maze. A total of 150 rats divided into fifteen groups were employed in the present study. The animals were subjected to different training sessions during first three days. The ability to retain the learned task was tested after single, sub-acute, acute, sub-chronic and chronic exposure to above exteroceptive memory models in separate groups of animals. The memory score of all animals was recorded after 72 h, 192 h and 432 h of their last training trial. Rats of single exposure group did not show any effect on memory. Sub-acute training group animals showed improved memory up to 72 h only, where as in acute and sub-chronic training groups this memory improvement was extended up to 192 h. The rats, which were subjected to chronic exposures showed a significant improvement in retention capacity that lasted up to a period of eighteen days. These observations suggest that repeated rehearsals at regular intervals are probably necessary for consolidation of long-term memory. It was observed that sub-acute, acute and sub-chronic exposures, improved the retrieval ability of rats but this memory improving effect was short lived. Thus, rehearsal or training plays a crucial role in enhancing one's capacity of retaining the learnt information

Model-based identification and use of task complexity factors of human integrated systems

International Nuclear Information System (INIS)

Ham, Dong-Han; Park, Jinkyun; Jung, Wondea

2012-01-01

Task complexity is one of the conceptual constructs that are critical to explain and predict human performance in human integrated systems. A basic approach to evaluating the complexity of tasks is to identify task complexity factors and measure them. Although a great deal of task complexity factors have been studied, there is still a lack of conceptual frameworks for identifying and organizing them analytically, which can be generally used irrespective of the types of domains and tasks. This study proposes a model-based approach to identifying and using task complexity factors, which has two facets—the design aspects of a task and complexity dimensions. Three levels of design abstraction, which are functional, behavioral, and structural aspects of a task, characterize the design aspect of a task. The behavioral aspect is further classified into five cognitive processing activity types. The complexity dimensions explain a task complexity from different perspectives, which are size, variety, and order/organization. Twenty-one task complexity factors are identified by the combination of the attributes of each facet. Identification and evaluation of task complexity factors based on this model is believed to give insights for improving the design quality of tasks. This model for complexity factors can also be used as a referential framework for allocating tasks and designing information aids. The proposed approach is applied to procedure-based tasks of nuclear power plants (NPPs) as a case study to demonstrate its use. Last, we compare the proposed approach with other studies and then suggest some future research directions.

Metaphor: Bridging embodiment to abstraction.

Science.gov (United States)

Jamrozik, Anja; McQuire, Marguerite; Cardillo, Eileen R; Chatterjee, Anjan

2016-08-01

Embodied cognition accounts posit that concepts are grounded in our sensory and motor systems. An important challenge for these accounts is explaining how abstract concepts, which do not directly call upon sensory or motor information, can be informed by experience. We propose that metaphor is one important vehicle guiding the development and use of abstract concepts. Metaphors allow us to draw on concrete, familiar domains to acquire and reason about abstract concepts. Additionally, repeated metaphoric use drawing on particular aspects of concrete experience can result in the development of new abstract representations. These abstractions, which are derived from embodied experience but lack much of the sensorimotor information associated with it, can then be flexibly applied to understand new situations.

Technical abstracts: Mechanical engineering, 1990

International Nuclear Information System (INIS)

Broesius, J.Y.

1991-01-01

This document is a compilation of the published, unclassified abstracts produced by mechanical engineers at Lawrence Livermore National Laboratory (LLNL) during the calendar year 1990. Many abstracts summarize work completed and published in report form. These are UCRL-JC series documents, which include the full text of articles to be published in journals and of papers to be presented at meetings, and UCID reports, which are informal documents. Not all UCIDs contain abstracts: short summaries were generated when abstracts were not included. Technical Abstracts also provides descriptions of those documents assigned to the UCRL-MI (miscellaneous) category. These are generally viewgraphs or photographs presented at meetings. An author index is provided at the back of this volume for cross referencing

Low-rank matrix approximation with manifold regularization.

Science.gov (United States)

Zhang, Zhenyue; Zhao, Keke

2013-07-01

This paper proposes a new model of low-rank matrix factorization that incorporates manifold regularization to the matrix factorization. Superior to the graph-regularized nonnegative matrix factorization, this new regularization model has globally optimal and closed-form solutions. A direct algorithm (for data with small number of points) and an alternate iterative algorithm with inexact inner iteration (for large scale data) are proposed to solve the new model. A convergence analysis establishes the global convergence of the iterative algorithm. The efficiency and precision of the algorithm are demonstrated numerically through applications to six real-world datasets on clustering and classification. Performance comparison with existing algorithms shows the effectiveness of the proposed method for low-rank factorization in general.

Regularity criteria for incompressible magnetohydrodynamics equations in three dimensions

International Nuclear Information System (INIS)

Lin, Hongxia; Du, Lili

2013-01-01

In this paper, we give some new global regularity criteria for three-dimensional incompressible magnetohydrodynamics (MHD) equations. More precisely, we provide some sufficient conditions in terms of the derivatives of the velocity or pressure, for the global regularity of strong solutions to 3D incompressible MHD equations in the whole space, as well as for periodic boundary conditions. Moreover, the regularity criterion involving three of the nine components of the velocity gradient tensor is also obtained. The main results generalize the recent work by Cao and Wu (2010 Two regularity criteria for the 3D MHD equations J. Diff. Eqns 248 2263–74) and the analysis in part is based on the works by Cao C and Titi E (2008 Regularity criteria for the three-dimensional Navier–Stokes equations Indiana Univ. Math. J. 57 2643–61; 2011 Gobal regularity criterion for the 3D Navier–Stokes equations involving one entry of the velocity gradient tensor Arch. Rational Mech. Anal. 202 919–32) for 3D incompressible Navier–Stokes equations. (paper)

The triconnected abstraction of process models

OpenAIRE

Polyvyanyy, Artem; Smirnov, Sergey; Weske, Mathias

2009-01-01

Contents: Artem Polyvanny, Sergey Smirnow, and Mathias Weske The Triconnected Abstraction of Process Models 1 Introduction 2 Business Process Model Abstraction 3 Preliminaries 4 Triconnected Decomposition 4.1 Basic Approach for Process Component Discovery 4.2 SPQR-Tree Decomposition 4.3 SPQR-Tree Fragments in the Context of Process Models 5 Triconnected Abstraction 5.1 Abstraction Rules 5.2 Abstraction Algorithm 6 Related Work and Conclusions

Can black-and-white ruffed lemurs (Varecia variegata) solve object permanence tasks?

Science.gov (United States)

Mallavarapu, Suma; Perdue, Bonnie M; Stoinski, Tara S; Maple, Terry L

2013-04-01

We examined object permanence in black-and-white-ruffed lemurs (Varecia variegata) at Zoo Atlanta. A series of visible and invisible displacement tasks with suitable controls were presented to five adult subjects. Subjects performed significantly above chance on all regular tasks, except for the double invisible displacements. Subjects failed visible and invisible controls. Failure on the control trials did not appear to be because subjects used the "last box touched" strategy (subjects did not choose the last box touched significantly more than expected by chance). However, a substantial percentage of choices was made to the last box touched by the experimenter. There was no significant difference between this percentage, and the percentage of choices made to the baited box (on both visible and invisible controls), which indicates that subjects were drawn to both boxes which the experimenter visited/touched, and thus failed the controls. Based on the results from the present study, we believe that there is no evidence that black-and-white ruffed lemurs understand visible and invisible tasks in the traditional object permanence battery. © 2013 Wiley Periodicals, Inc.

Regular-fat dairy and human health

DEFF Research Database (Denmark)

Astrup, Arne; Bradley, Beth H Rice; Brenna, J Thomas

2016-01-01

In recent history, some dietary recommendations have treated dairy fat as an unnecessary source of calories and saturated fat in the human diet. These assumptions, however, have recently been brought into question by current research on regular fat dairy products and human health. In an effort to......, cheese and yogurt, can be important components of an overall healthy dietary pattern. Systematic examination of the effects of dietary patterns that include regular-fat milk, cheese and yogurt on human health is warranted....

Bounded Perturbation Regularization for Linear Least Squares Estimation

KAUST Repository

Ballal, Tarig; Suliman, Mohamed Abdalla Elhag; Al-Naffouri, Tareq Y.

2017-01-01

This paper addresses the problem of selecting the regularization parameter for linear least-squares estimation. We propose a new technique called bounded perturbation regularization (BPR). In the proposed BPR method, a perturbation with a bounded

Recognition Memory for Novel Stimuli: The Structural Regularity Hypothesis

Science.gov (United States)

Cleary, Anne M.; Morris, Alison L.; Langley, Moses M.

2007-01-01

Early studies of human memory suggest that adherence to a known structural regularity (e.g., orthographic regularity) benefits memory for an otherwise novel stimulus (e.g., G. A. Miller, 1958). However, a more recent study suggests that structural regularity can lead to an increase in false-positive responses on recognition memory tests (B. W. A.…

Alteration of Neurokinin B Gene Expression and Hypothalamic-Pituitary- Gonadal Axis in Response to One-month Regular Moderate Physical Activity

Directory of Open Access Journals (Sweden)

Nazli Khajehnasiri

2017-08-01

Full Text Available Abstract Background: The advantageous effects of the regular moderate physical activity (Exercise on reproduction is widely accepted, but until now, the alterations of the expression of hypothalamic arcuate nuclei gene affecting on reproduction axis in response to this type of physical activity are not clear. Therefore, the goal of the present investigation was to study the effect of one –month regular moderate physical activity on neurokinin B gene expression and reproductive axis hormonal changes. Materials and Methods: In the experimental study, fourteen adult male Wistar rats were randomly divided into control and one- month regular moderate exercise groups. After one - month physical activity (20m/min, the arcuate nucleus was isolated from brain and stored in -80 refrigerators for neurokinin B gene expression assay by Real-time PCR method. In addition, serum samples were taken to assess the corticosterone, luteinizing hormone and testosterone levels by ELISA method. Data were analyzed by Independent t-test in SPSS. Results: Neurokinin-B gene expression level was lower in the group which received physical activity than the control group(p<0.05. Also, corticosterone serum concentration was decreased in the physical activity group(p<0.05. By contrast, the physical activity induced luteinizing hormone and Testosterone serum levels evaluation in exersice group compared with control group (p<0.05. Conclusion: Regular moderate physical activity may improve male reproductive performance by reducing the corticosterone hormone level and decreasing neurokinin B expression.

A Modal-Logic Based Graph Abstraction

NARCIS (Netherlands)

Bauer, J.; Boneva, I.B.; Kurban, M.E.; Rensink, Arend; Ehrig, H; Heckel, R.; Rozenberg, G.; Taentzer, G.

2008-01-01

Infinite or very large state spaces often prohibit the successful verification of graph transformation systems. Abstract graph transformation is an approach that tackles this problem by abstracting graphs to abstract graphs of bounded size and by lifting application of productions to abstract

Increasing On-Task Behavior in Students in a Regular Classroom: Effectiveness of a Self-Management Procedure Using a Tactile Prompt

NARCIS (Netherlands)

Moore, D.W.; Anderson, A.; Glassenbury, M.; Didden, H.C.M.; Lang, R.B.

2013-01-01

Self-management strategies have been shown to be widely effective. However, limited classroom-based research exists involving low performing but developmentally normal high school-aged participants. This study examined the effectiveness of a self-management strategy aimed at increasing on-task

Seismic Consequence Abstraction

International Nuclear Information System (INIS)

Gross, M.

2004-01-01

The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274])

Seismic Consequence Abstraction

Energy Technology Data Exchange (ETDEWEB)

M. Gross

2004-10-25

The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

Modal abstractions of concurrent behavior

DEFF Research Database (Denmark)

Nielson, Flemming; Nanz, Sebastian; Nielson, Hanne Riis

2011-01-01

We present an effective algorithm for the automatic construction of finite modal transition systems as abstractions of potentially infinite concurrent processes. Modal transition systems are recognized as valuable abstractions for model checking because they allow for the validation as well...... as refutation of safety and liveness properties. However, the algorithmic construction of finite abstractions from potentially infinite concurrent processes is a missing link that prevents their more widespread usage for model checking of concurrent systems. Our algorithm is a worklist algorithm using concepts...... from abstract interpretation and operating upon mappings from sets to intervals in order to express simultaneous over- and underapprox-imations of the multisets of process actions available in a particular state. We obtain a finite abstraction that is 3-valued in both states and transitions...