Single or Dual Representations for Reading and Spelling?
ERIC Educational Resources Information Center
Holmes, Virginia M.; Babauta, Mariko L.
2005-01-01
Neuropsychological models postulate that the memory representation acquired for use in reading words is separate from the one acquired for use in spelling, while developmental models assume that the same representation is developed for access in both reading and spelling. The dual-representation model contends that there is often more precise…
Holographic representation of higher spin gauge fields
NASA Astrophysics Data System (ADS)
Sarkar, Debajyoti; Xiao, Xiao
2015-04-01
Extending the results of [1,2] on the holographic representation of local gauge field operators in anti-de Sitter space, here we construct the bulk operators for higher spin gauge fields at the leading order in 1/N expansion. Working in the holographic gauge for higher spin gauge fields, we show that gauge field operators with integer spin s >1 can be represented by an integration over a ball region, which is the interior region of the spacelike bulk light cone on the boundary. The construction is shown to be anti-de Sitter covariant up to gauge transformations, and the two-point function between higher spin gauge fields and the boundary higher spin current exhibits singularities on both bulk and boundary light cones. We also comment on a possible extension to the level of three-point functions and carry out a causal construction for higher spin fields in de Sitter spacetime.
Dual character concepts and the normative dimension of conceptual representation.
Knobe, Joshua; Prasada, Sandeep; Newman, George E
2013-05-01
Five experiments provide evidence for a class of 'dual character concepts.' Dual character concepts characterize their members in terms of both (a) a set of concrete features and (b) the abstract values that these features serve to realize. As such, these concepts provide two bases for evaluating category members and two different criteria for category membership. Experiment 1 provides support for the notion that dual character concepts have two bases for evaluation. Experiments 2-4 explore the claim that dual character concepts have two different criteria for category membership. The results show that when an object possesses the appropriate concrete features, but does not fulfill the appropriate abstract value, it is judged to be a category member in one sense but not in another. Finally, Experiment 5 uses the theory developed here to construct artificial dual character concepts and examines whether participants react to these artificial concepts in the same way as naturally occurring dual character concepts. The present studies serve to define the nature of dual character concepts and distinguish them from other types of concepts (e.g., natural kind concepts), which share some, but not all of the properties of dual character concepts. More broadly, these phenomena suggest a normative dimension in everyday conceptual representation. PMID:23454798
Children's Learning from Touch Screens: A Dual Representation Perspective.
Sheehan, Kelly J; Uttal, David H
2016-01-01
Parents and educators often expect that children will learn from touch screen devices, such as during joint e-book reading. Therefore an essential question is whether young children understand that the touch screen can be a symbolic medium - that entities represented on the touch screen can refer to entities in the real world. Research on symbolic development suggests that symbolic understanding requires that children develop dual representational abilities, meaning children need to appreciate that a symbol is an object in itself (i.e., picture of a dog) while also being a representation of something else (i.e., the real dog). Drawing on classic research on symbols and new research on children's learning from touch screens, we offer the perspective that children's ability to learn from the touch screen as a symbolic medium depends on the effect of interactivity on children's developing dual representational abilities. Although previous research on dual representation suggests the interactive nature of the touch screen might make it difficult for young children to use as a symbolic medium, the unique interactive affordances may help alleviate this difficulty. More research needs to investigate how the interactivity of the touch screen affects children's ability to connect the symbols on the screen to the real world. Given the interactive nature of the touch screen, researchers and educators should consider both the affordances of the touch screen as well as young children's cognitive abilities when assessing whether young children can learn from it as a symbolic medium. PMID:27570516
The Linked Dual Representation model of vocal perception and production
Hutchins, Sean; Moreno, Sylvain
2013-01-01
The voice is one of the most important media for communication, yet there is a wide range of abilities in both the perception and production of the voice. In this article, we review this range of abilities, focusing on pitch accuracy as a particularly informative case, and look at the factors underlying these abilities. Several classes of models have been posited describing the relationship between vocal perception and production, and we review the evidence for and against each class of model. We look at how the voice is different from other musical instruments and review evidence about both the association and the dissociation between vocal perception and production abilities. Finally, we introduce the Linked Dual Representation (LDR) model, a new approach which can account for the broad patterns in prior findings, including trends in the data which might seem to be countervailing. We discuss how this model interacts with higher-order cognition and examine its predictions about several aspects of vocal perception and production. PMID:24204360
Workplace Learning in Dual Higher Professional Education
ERIC Educational Resources Information Center
Poortman, Cindy L.; Reenalda, Marloes; Nijhof, Wim J.; Nieuwenhuis, Loek F. M.
2014-01-01
Workplace learning is considered an effective strategy for the development of vocation, career and professional identity. Dual training programs, in which learning at a vocational school and learning at work in a company are combined, are seen as strong carriers for skill formation processes. In this study we explore workplace learning in dual…
Dual-Career Couples in Higher Education.
ERIC Educational Resources Information Center
Weishaar, Marjorie; And Others
1984-01-01
Surveyed 45 dual-career couples to identify conflicts and solutions of professinals pursuing academic careers and bearing family responsibilities. Compared males and females, couples with children and those without, couples under 40 years of age and older couples, and this sample with one from business and industry. (Author/JAC)
Australian Indigenous Higher Education: Politics, Policy and Representation
ERIC Educational Resources Information Center
Wilson, Katie; Wilks, Judith
2015-01-01
The growth of Aboriginal and Torres Strait Islander participation in Australian higher education from 1959 to the present is notable statistically, but below population parity. Distinct patterns in government policy-making and programme development, inconsistent funding and political influences, together with Indigenous representation during the…
Symplectic representation of higher-order guiding-center theory
NASA Astrophysics Data System (ADS)
Brizard, Alain; Tronko, Natalia
2012-03-01
Two representations of guiding-center theory are possible depending on whether the guiding-center Poisson bracket (i.e., the symplectic structure) or the Hamiltonian contains higher-order corrections due to the nonuniformity of the magnetic field. By combining the guiding-center parallel hierarchy with the symplectic representation, the guiding-center equations of motion are derived with second-order corrections included in the symplectic structure without the need of carrying out the guiding-center transformation to second order. Guiding-center polarization and magnetization are thus shown to arise naturally from higher-order guiding-center theory within the context of a two-step derivation of nonlinear gyrokinetic theory.footnotetextA. J. Brizard and T. S. Hahm, Rev. Mod. Phys. 79, 421 (2007).
The Effects of Single and Dual Representations on Children's Gesture Production
ERIC Educational Resources Information Center
Thurnham, Angela J.; Pine, Karen J.
2006-01-01
Investigations that focus on children's hand gestures often conclude that gesture production arises as a result of having multiple representations. To date, the predictive validity of this notion has not been tested. In this study, we compared the gestures of 82 five-year-old children holding either a single or a dual representation. The children…
Dual Character Concepts and the Normative Dimension of Conceptual Representation
ERIC Educational Resources Information Center
Knobe, Joshua; Prasada, Sandeep; Newman, George E.
2013-01-01
Five experiments provide evidence for a class of "dual character concepts." Dual character concepts characterize their members in terms of both (a) a set of concrete features and (b) the abstract values that these features serve to realize. As such, these concepts provide two bases for evaluating category members and two different criteria for…
RENORMALIZATION OF POLYAKOV LOOPS IN FUNDAMENTAL AND HIGHER REPRESENTATIONS
KACZMAREK,O.; GUPTA, S.; HUEBNER, K.
2007-07-30
We compare two renormalization procedures, one based on the short distance behavior of heavy quark-antiquark free energies and the other by using bare Polyakov loops at different temporal entent of the lattice and find that both prescriptions are equivalent, resulting in renormalization constants that depend on the bare coupling. Furthermore these renormalization constants show Casimir scaling for higher representations of the Polyakov loops. The analysis of Polyakov loops in different representations of the color SU(3) group indicates that a simple perturbative inspired relation in terms of the quadratic Casimir operator is realized to a good approximation at temperatures T{approx}>{Tc}, for renormalized as well as bare loops. In contrast to a vanishing Polyakov loop in representations with non-zero triality in the confined phase, the adjoint loops are small but non-zero even for temperatures below the critical one. The adjoint quark-antiquark pairs exhibit screening. This behavior can be related to the binding energy of glue-lump states.
Dual-Process Theories of Higher Cognition: Advancing the Debate.
Evans, Jonathan St B T; Stanovich, Keith E
2013-05-01
Dual-process and dual-system theories in both cognitive and social psychology have been subjected to a number of recently published criticisms. However, they have been attacked as a category, incorrectly assuming there is a generic version that applies to all. We identify and respond to 5 main lines of argument made by such critics. We agree that some of these arguments have force against some of the theories in the literature but believe them to be overstated. We argue that the dual-processing distinction is supported by much recent evidence in cognitive science. Our preferred theoretical approach is one in which rapid autonomous processes (Type 1) are assumed to yield default responses unless intervened on by distinctive higher order reasoning processes (Type 2). What defines the difference is that Type 2 processing supports hypothetical thinking and load heavily on working memory. PMID:26172965
NASA Astrophysics Data System (ADS)
Schreiber, Tomasz
2010-08-01
We consider polygonal Markov fields originally introduced by Arak in 4th USSR-Japan Symposium on Probability Theory and Mathematical Statistics, Abstracts of Communications, 1982; Arak and Surgailis in Probab. Theory Relat. Fields 80:543-579, 1989. Our attention is focused on fields with nodes of order two, which can be regarded as continuum ensembles of non-intersecting contours in the plane, sharing a number of salient features with the two-dimensional Ising model. The purpose of this paper is to establish an explicit stochastic representation for the higher-order correlation functions of polygonal Markov fields in their consistency regime. The representation is given in terms of the so-called crop functionals (defined by a Möbius-type formula) of polygonal webs which arise in a graphical construction dual to that giving rise to polygonal fields. The proof of our representation formula goes by constructing a martingale interpolation between the correlation functions of polygonal fields and crop functionals of polygonal webs.
Detection of dual-band infrared small target based on joint dynamic sparse representation
NASA Astrophysics Data System (ADS)
Zhou, Jinwei; Li, Jicheng; Shi, Zhiguang; Lu, Xiaowei; Ren, Dongwei
2015-10-01
Infrared small target detection is a crucial and yet still is a difficult issue in aeronautic and astronautic applications. Sparse representation is an important mathematic tool and has been used extensively in image processing in recent years. Joint sparse representation is applied in dual-band infrared dim target detection in this paper. Firstly, according to the characters of dim targets in dual-band infrared images, 2-dimension Gaussian intensity model was used to construct target dictionary, then the dictionary was classified into different sub-classes according to different positions of Gaussian function's center point in image block; The fact that dual-band small targets detection can use the same dictionary and the sparsity doesn't lie in atom-level but in sub-class level was utilized, hence the detection of targets in dual-band infrared images was converted to be a joint dynamic sparse representation problem. And the dynamic active sets were used to describe the sparse constraint of coefficients. Two modified sparsity concentration index (SCI) criteria was proposed to evaluate whether targets exist in the images. In experiments, it shows that the proposed algorithm can achieve better detecting performance and dual-band detection is much more robust to noise compared with single-band detection. Moreover, the proposed method can be expanded to multi-spectrum small target detection.
A CAD system based on spherical dual representations
Roach, J.W.; Paripati, P.K.; Wright, J.S.
1987-08-01
Computer-aided design (CAD) systems typically have many different functions: drafting, two-dimensional modeling, three-dimensional modeling, finite element analysis, and fit and tolerancing of parts. The authors report on the construction of a CAD system based on shape representation ideas used in the vision community to determine the shape of an object from its image. In the long term, they propose to construct a combined CAD and sensing system based on the same underlying object models. Considerable advantages follow from building a model-driven sensor fusion system that uses a common geometric model. In a manufacturing environment, for example, a library of objects can be built up and its models used in a vision and touch sensing system integrated into an automated assembly line to discriminate between objects and determine orientation and distance. If such a system could be made robust and highly reliable, then some of the most difficult problems that plague attempts to create a fully flexible automated environment would be solved.
Higher Order Pattern Structure Influences Auditory Representational Momentum
ERIC Educational Resources Information Center
Johnston, Heather Moynihan; Jones, Mari Riess
2006-01-01
Representational momentum refers to the phenomenon that observers tend to incorrectly remember an event undergoing real or implied motion as shifted beyond its actual final position. This has been demonstrated in both visual and auditory domains. In 5 pitch discrimination experiments, listeners heard tone sequences that implied either linear,…
Vehicle path planning via dual-world representations
NASA Astrophysics Data System (ADS)
Peck, Alex N.; Breul, Harry T.
1991-03-01
A technique is developed whereby a mobile robot equipped with sonar sensors autonomously explores a hallway environment and during exploration dynamically builds two types of maps: a graph of places defined by distinctive sonar events and a grid map from dead reckoning data that is accurate in the neighborhood of a place. With both maps available the robot can quickly plan a path between arbitrary locations and then define a sequence of behaviors that will move the robot along the selected path. Robust performance is achieved by dividing the computational processes into two parallel operations. Time-critical low-level behaviors like driving and steering in the exploratory mode are controlled by an onboard computer that uses sonar data as input to simple subsumption-based algorithms. 1 Higher level more computationally intense and less-time-critical activities like place designation map making display generation and path planning are performed in parallel on a remote computer that fetches sonar data and issues high-level commands via a radio link. An approach to integrating this work with efforts in planning and navigation to form a larger activity in intelligent vehicle research is discussed in a companion paper.
The free energy of higher representation sources in lattice gauge theories
NASA Astrophysics Data System (ADS)
Damgaard, P. H.
1987-07-01
Deconfinement of higher representation sources in SU(2) lattice gauge theory is studied by a Monte Carlo simulation on an 83×2 lattice. Results for the free energy are compared with expectations from the effective theory of thermal Polyakov loops, and critical exponents for the magnetization of different representations in SU(2) are computed. We also compare the predictions for higher representations in SU(3) lattice gauge theory with some recent Monte Carlo data. Finally, possible phenomenological consequences of the deconfinement associated with higher representation sources are discussed. I would like to thank Urs Heller and Alan Luther for helpful discussions.
Dual representation for the generating functional of the Feynman path-integral
NASA Astrophysics Data System (ADS)
Matone, Marco
2016-09-01
The generating functional for scalar theories admits a representation which is dual with respect to the one introduced by Schwinger, interchanging the role of the free and interacting terms. It maps $\\int V(\\delta_J)$ and $J\\Delta J$ to $\\delta_{\\phi_c}\\Delta\\delta_{\\phi_c}$ and $\\int V(\\phi_c)$, respectively, with $\\phi_c=\\int J\\Delta$ and $\\Delta$ the Feynman propagator. Comparing the Schwinger representation with its dual version one gets a little known relation that we prove to be a particular case of a more general operatorial relation. We then derive a new representation of the generating functional $T[\\phi_c]=W[J]$ expressed in terms of covariant derivatives acting on 1 $$ T[\\phi_c] = {N\\over N_0} \\exp(-U_0[\\phi_c])\\exp\\Big(-\\int V({\\cal D}_{\\phi_c}^-)\\Big) \\cdot 1 $$ where ${\\cal D}_{\\phi}^{\\pm}(x)=\\mp\\Delta{\\delta\\over\\delta\\phi}(x)+\\phi(x)$. The dual representation, which is deeply related to the Hermite polynomials, is the key to express the generating functional associated to a sum of potentials in terms of factorized generating functionals. This is applied to renormalization, leading to a factorization of the counterterms of the interaction. We investigate the structure of the functional generator for normal ordered potentials and derive an infinite set of relations in the case of the potential ${\\lambda\\over n!}:\\phi^n:$. Such relations are explicitly derived by using the Fa\\`a di Bruno formula. This also yields the explicit expression of the generating functional of connected Green's functions.
Children’s Learning from Touch Screens: A Dual Representation Perspective
Sheehan, Kelly J.; Uttal, David H.
2016-01-01
Parents and educators often expect that children will learn from touch screen devices, such as during joint e-book reading. Therefore an essential question is whether young children understand that the touch screen can be a symbolic medium – that entities represented on the touch screen can refer to entities in the real world. Research on symbolic development suggests that symbolic understanding requires that children develop dual representational abilities, meaning children need to appreciate that a symbol is an object in itself (i.e., picture of a dog) while also being a representation of something else (i.e., the real dog). Drawing on classic research on symbols and new research on children’s learning from touch screens, we offer the perspective that children’s ability to learn from the touch screen as a symbolic medium depends on the effect of interactivity on children’s developing dual representational abilities. Although previous research on dual representation suggests the interactive nature of the touch screen might make it difficult for young children to use as a symbolic medium, the unique interactive affordances may help alleviate this difficulty. More research needs to investigate how the interactivity of the touch screen affects children’s ability to connect the symbols on the screen to the real world. Given the interactive nature of the touch screen, researchers and educators should consider both the affordances of the touch screen as well as young children’s cognitive abilities when assessing whether young children can learn from it as a symbolic medium. PMID:27570516
ERIC Educational Resources Information Center
Garrod, Neil; Macfarlane, Bruce
2007-01-01
Dual sector universities (or duals) are a growing international phenomenon that cut across the divide that typically exists in post-secondary education. Duals combine "further" and "higher" education within a single institution providing enhanced opportunities for student transition between post-secondary sectors. This paper reports the results of…
Brewin, Chris R; Burgess, Neil
2014-03-01
Three recent studies (Pearson, 2012; Pearson, Ross, & Webster, 2012) purported to test the revised dual representation theory of posttraumatic stress disorder (Brewin, Gregory, Lipton, & Burgess, 2010) by manipulating the amount of additional information accompanying traumatic stimulus materials and assessing the effect on subsequent intrusive memories. Here we point out that these studies involve a misunderstanding of the meaning of "contextual" within the theory, such that the manipulation would be unlikely to have had the intended effect and the results are ambiguous with respect to the theory. Past and future experimental tests of the theory are discussed. PMID:24041427
Conformal window of SU(N) gauge theories with fermions in higher dimensional representations
Dietrich, Dennis D.; Sannino, Francesco
2007-04-15
We study the phase diagram as a function of the number of colors and flavors of asymptotically free nonsupersymmetric theories with matter in higher-dimensional representations of arbitrary SU(N) gauge groups. Since matter in higher-dimensional representations screens more than in the fundamental a general feature is that a lower number of flavors is needed to achieve a near-conformal theory.
Sound representation in higher language areas during language generation
Magrassi, Lorenzo; Aromataris, Giuseppe; Cabrini, Alessandro; Annovazzi-Lodi, Valerio; Moro, Andrea
2015-01-01
How language is encoded by neural activity in the higher-level language areas of humans is still largely unknown. We investigated whether the electrophysiological activity of Broca’s area correlates with the sound of the utterances produced. During speech perception, the electric cortical activity of the auditory areas correlates with the sound envelope of the utterances. In our experiment, we compared the electrocorticogram recorded during awake neurosurgical operations in Broca’s area and in the dominant temporal lobe with the sound envelope of single words versus sentences read aloud or mentally by the patients. Our results indicate that the electrocorticogram correlates with the sound envelope of the utterances, starting before any sound is produced and even in the absence of speech, when the patient is reading mentally. No correlations were found when the electrocorticogram was recorded in the superior parietal gyrus, an area not directly involved in language generation, or in Broca’s area when the participants were executing a repetitive motor task, which did not include any linguistic content, with their dominant hand. The distribution of suprathreshold correlations across frequencies of cortical activities varied whether the sound envelope derived from words or sentences. Our results suggest the activity of language areas is organized by sound when language is generated before any utterance is produced or heard. PMID:25624479
Sound representation in higher language areas during language generation.
Magrassi, Lorenzo; Aromataris, Giuseppe; Cabrini, Alessandro; Annovazzi-Lodi, Valerio; Moro, Andrea
2015-02-10
How language is encoded by neural activity in the higher-level language areas of humans is still largely unknown. We investigated whether the electrophysiological activity of Broca's area correlates with the sound of the utterances produced. During speech perception, the electric cortical activity of the auditory areas correlates with the sound envelope of the utterances. In our experiment, we compared the electrocorticogram recorded during awake neurosurgical operations in Broca's area and in the dominant temporal lobe with the sound envelope of single words versus sentences read aloud or mentally by the patients. Our results indicate that the electrocorticogram correlates with the sound envelope of the utterances, starting before any sound is produced and even in the absence of speech, when the patient is reading mentally. No correlations were found when the electrocorticogram was recorded in the superior parietal gyrus, an area not directly involved in language generation, or in Broca's area when the participants were executing a repetitive motor task, which did not include any linguistic content, with their dominant hand. The distribution of suprathreshold correlations across frequencies of cortical activities varied whether the sound envelope derived from words or sentences. Our results suggest the activity of language areas is organized by sound when language is generated before any utterance is produced or heard. PMID:25624479
Urban traffic simulated from the dual representation: Flow, crisis and congestion
NASA Astrophysics Data System (ADS)
Hu, Mao-Bin; Jiang, Rui; Wang, Ruili; Wu, Qing-Song
2009-05-01
We propose a traffic simulation model for urban system based on the dual graph representation of a urban road network and with a random entering vehicle rate. To avoid the shortcoming of “Space Syntax” of ignoring the road's metric distance, we consider both the motion of the vehicles along roads and the navigation of the vehicles in the network. Simulations have shown some basic properties of urban traffic system, such as flux fluctuation, crisis and dissipation, phase transition from a free flow to jams, overall capacity, the distribution of traveling time, and the fundamental diagram. The system's behavior greatly depends on the topology of the transportation network. A well-planned lattice grid can keep more vehicles travelling. The critical entering vehicle rate is much greater in lattice grid than in a self-organized network. The vehicles have to travel longer time in a self-organized urban system due to the navigation cost.
ERIC Educational Resources Information Center
Schuch, Stefanie; Koch, Iring
2004-01-01
In 5 experiments, the authors investigated the costs associated with repeating the same or a similar response in a dual-task setting. Using a psychological refractory period paradigm, they obtained response-repetition costs when the cognitive representation of a specific response (i.e., the category-response mapping) changed (Experiment 1) but…
Dual-Mode Universities in Higher Education: Way Station or Final Destination?
ERIC Educational Resources Information Center
Daniel, John
2012-01-01
In the title the author asked whether dual-mode institutions were a stable "final" model for higher education or a step on the way to something else. Only a few institutions seem able to function in dual mode (i.e. with distinct groups of distance and classroom students) in a successful and sustainable way. Some institutions now claim that all…
Female Representation in the Higher Education of Geography in Hungary. Symposium
ERIC Educational Resources Information Center
Timar, Judit; Jelenszkyne, Ildiko Fabian
2004-01-01
This paper charts the changing female representation in the higher education of geography, connecting it with the faltering development of feminist geography in Hungary. The transition from socialism to capitalism has compounded gender inequalities while many of the relevant statistical data display gender blindness. Gender issues fail to form a…
ERIC Educational Resources Information Center
Marschke, Robyn; Laursen, Sandra; Nielsen, Joyce McCarl; Rankin, Patricia
2007-01-01
Progress toward equitable gender representation among faculty in higher education has been "glacial" since the early 1970s (Glazer-Raymo, 1999; Lomperis, 1990; Trower & Chait, 2002). Women, who now make up a majority of undergraduate degree earners and approximately 46% of Ph.D. earners nationwide (National Center for Education Statistics [NCES],…
Color-motion feature-binding errors are mediated by a higher-order chromatic representation.
Shevell, Steven K; Wang, Wei
2016-03-01
Peripheral and central moving objects of the same color may be perceived to move in the same direction even though peripheral objects have a different true direction of motion [Nature429, 262 (2004)10.1038/429262a]. The perceived, illusory direction of peripheral motion is a color-motion feature-binding error. Recent work shows that such binding errors occur even without an exact color match between central and peripheral objects, and, moreover, the frequency of the binding errors in the periphery declines as the chromatic difference increases between the central and peripheral objects [J. Opt. Soc. Am. A31, A60 (2014)JOAOD60740-323210.1364/JOSAA.31.000A60]. This change in the frequency of binding errors with the chromatic difference raises the general question of the chromatic representation from which the difference is determined. Here, basic properties of the chromatic representation are tested to discover whether it depends on independent chromatic differences on the l and the s cardinal axes or, alternatively, on a more specific higher-order chromatic representation. Experimental tests compared the rate of feature-binding errors when the central and peripheral colors had the identical s chromaticity (so zero difference in s) and a fixed magnitude of l difference, while varying the identical s level in center and periphery (thus always keeping the s difference at zero). A chromatic representation based on independent l and s differences would result in the same frequency of color-motion binding errors at everyslevel. The results are contrary to this prediction, thus showing that the chromatic representation at the level of color-motion feature binding depends on a higher-order chromatic mechanism. PMID:26974945
Lesaint, Florian; Sigaud, Olivier; Khamassi, Mehdi
2014-01-01
Animals, including Humans, are prone to develop persistent maladaptive and suboptimal behaviours. Some of these behaviours have been suggested to arise from interactions between brain systems of Pavlovian conditioning, the acquisition of responses to initially neutral stimuli previously paired with rewards, and instrumental conditioning, the acquisition of active behaviours leading to rewards. However the mechanics of these systems and their interactions are still unclear. While extensively studied independently, few models have been developed to account for these interactions. On some experiment, pigeons have been observed to display a maladaptive behaviour that some suggest to involve conflicts between Pavlovian and instrumental conditioning. In a procedure referred as negative automaintenance, a key light is paired with the subsequent delivery of food, however any peck towards the key light results in the omission of the reward. Studies showed that in such procedure some pigeons persisted in pecking to a substantial level despite its negative consequence, while others learned to refrain from pecking and maximized their cumulative rewards. Furthermore, the pigeons that were unable to refrain from pecking could nevertheless shift their pecks towards a harmless alternative key light. We confronted a computational model that combines dual-learning systems and factored representations, recently developed to account for sign-tracking and goal-tracking behaviours in rats, to these negative automaintenance experimental data. We show that it can explain the variability of the observed behaviours and the capacity of alternative key lights to distract pigeons from their detrimental behaviours. These results confirm the proposed model as an interesting tool to reproduce experiments that could involve interactions between Pavlovian and instrumental conditioning. The model allows us to draw predictions that may be experimentally verified, which could help further investigate
Lesaint, Florian; Sigaud, Olivier; Khamassi, Mehdi
2014-01-01
Animals, including Humans, are prone to develop persistent maladaptive and suboptimal behaviours. Some of these behaviours have been suggested to arise from interactions between brain systems of Pavlovian conditioning, the acquisition of responses to initially neutral stimuli previously paired with rewards, and instrumental conditioning, the acquisition of active behaviours leading to rewards. However the mechanics of these systems and their interactions are still unclear. While extensively studied independently, few models have been developed to account for these interactions. On some experiment, pigeons have been observed to display a maladaptive behaviour that some suggest to involve conflicts between Pavlovian and instrumental conditioning. In a procedure referred as negative automaintenance, a key light is paired with the subsequent delivery of food, however any peck towards the key light results in the omission of the reward. Studies showed that in such procedure some pigeons persisted in pecking to a substantial level despite its negative consequence, while others learned to refrain from pecking and maximized their cumulative rewards. Furthermore, the pigeons that were unable to refrain from pecking could nevertheless shift their pecks towards a harmless alternative key light. We confronted a computational model that combines dual-learning systems and factored representations, recently developed to account for sign-tracking and goal-tracking behaviours in rats, to these negative automaintenance experimental data. We show that it can explain the variability of the observed behaviours and the capacity of alternative key lights to distract pigeons from their detrimental behaviours. These results confirm the proposed model as an interesting tool to reproduce experiments that could involve interactions between Pavlovian and instrumental conditioning. The model allows us to draw predictions that may be experimentally verified, which could help further investigate
Bounding higher-order ionosphere errors for the dual-frequency GPS user
NASA Astrophysics Data System (ADS)
Datta-Barua, S.; Walter, T.; Blanch, J.; Enge, P.
2008-10-01
Civil signals at L2 and L5 frequencies herald a new phase of Global Positioning System (GPS) performance. Dual-frequency users typically assume a first-order approximation of the ionosphere index of refraction, combining the GPS observables to eliminate most of the ranging delay, on the order of meters, introduced into the pseudoranges. This paper estimates the higher-order group and phase errors that occur from assuming the ordinary first-order dual-frequency ionosphere model using data from the Federal Aviation Administration's Wide Area Augmentation System (WAAS) network on a solar maximum quiet day and an extremely stormy day postsolar maximum. We find that during active periods, when ionospheric storms may introduce slant range delays at L1 as high as 100 m, the higher-order group errors in the L1-L2 or L1-L5 dual-frequency combination can be tens of centimeters. The group and phase errors are no longer equal and opposite, so these errors accumulate in carrier smoothing of the dual-frequency code observable. We show the errors in the carrier-smoothed code are due to higher-order group errors and, to a lesser extent, to higher-order phase rate errors. For many applications, this residual error is sufficiently small as to be neglected. However, such errors can impact geodetic applications as well as the error budgets of GPS Augmentation Systems providing Category III precision approach.
Review of Dual Admissions Agreements and Programs in the Virginia Higher Education System
ERIC Educational Resources Information Center
State Council of Higher Education for Virginia, 2010
2010-01-01
The State Council of Higher Education for Virginia (SCHEV) is gathering information about the extent to which dual admissions agreements and programs between two- and four-year institutions have been developed in the Commonwealth. This is in response to the State Transfer Module legislation passed in 2004 requiring that two- and four-year…
Higher representations on the lattice: Numerical simulations, SU(2) with adjoint fermions
Del Debbio, Luigi; Patella, Agostino; Pica, Claudio
2010-05-01
We discuss the lattice formulation of gauge theories with fermions in arbitrary representations of the color group and present in detail the implementation of the hybrid Monte Carlo (HMC)/rational HMC algorithm for simulating dynamical fermions. We discuss the validation of the implementation through an extensive set of tests and the stability of simulations by monitoring the distribution of the lowest eigenvalue of the Wilson-Dirac operator. Working with two flavors of Wilson fermions in the adjoint representation, benchmark results for realistic lattice simulations are presented. Runs are performed on different lattice sizes ranging from 4{sup 3}x8 to 24{sup 3}x64 sites. For the two smallest lattices we also report the measured values of benchmark mesonic observables. These results can be used as a baseline for rapid cross-checks of simulations in higher representations. The results presented here are the first steps toward more extensive investigations with controlled systematic errors, aiming at a detailed understanding of the phase structure of these theories, and of their viability as candidates for strong dynamics beyond the standard model.
MaBouDi, HaDi; Shimazaki, Hideaki; Amari, Shun-Ichi; Soltanian-Zadeh, Hamid
2016-03-01
Natural scenes contain richer perceptual information in their spatial phase structure than their amplitudes. Modeling phase structure of natural scenes may explain higher-order structure inherent to the natural scenes, which is neglected in most classical models of redundancy reduction. Only recently, a few models have represented images using a complex form of receptive fields (RFs) and analyze their complex responses in terms of amplitude and phase. However, these complex representation models often tacitly assume a uniform phase distribution without empirical support. The structure of spatial phase distributions of natural scenes in the form of relative contributions of paired responses of RFs in quadrature has not been explored statistically until now. Here, we investigate the spatial phase structure of natural scenes using complex forms of various Gabor-like RFs. To analyze distributions of the spatial phase responses, we constructed a mixture model that accounts for multi-modal circular distributions, and the EM algorithm for estimation of the model parameters. Based on the likelihood, we report presence of both uniform and structured bimodal phase distributions in natural scenes. The latter bimodal distributions were symmetric with two peaks separated by about 180°. Thus, the redundancy in the natural scenes can be further removed by using the bimodal phase distributions obtained from these RFs in the complex representation models. These results predict that both phase invariant and phase sensitive complex cells are required to represent the regularities of natural scenes in visual systems. PMID:26278166
Using the Dual-Target Cost to Explore the Nature of Search Target Representations
ERIC Educational Resources Information Center
Stroud, Michael J.; Menneer, Tamaryn; Cave, Kyle R.; Donnelly, Nick
2012-01-01
Eye movements were monitored to examine search efficiency and infer how color is mentally represented to guide search for multiple targets. Observers located a single color target very efficiently by fixating colors similar to the target. However, simultaneous search for 2 colors produced a dual-target cost. In addition, as the similarity between…
A geometric modeler based on a dual-geometry representation polyhedra and rational b-splines
NASA Technical Reports Server (NTRS)
Klosterman, A. L.
1984-01-01
For speed and data base reasons, solid geometric modeling of large complex practical systems is usually approximated by a polyhedra representation. Precise parametric surface and implicit algebraic modelers are available but it is not yet practical to model the same level of system complexity with these precise modelers. In response to this contrast the GEOMOD geometric modeling system was built so that a polyhedra abstraction of the geometry would be available for interactive modeling without losing the precise definition of the geometry. Part of the reason that polyhedra modelers are effective is that all bounded surfaces can be represented in a single canonical format (i.e., sets of planar polygons). This permits a very simple and compact data structure. Nonuniform rational B-splines are currently the best representation to describe a very large class of geometry precisely with one canonical format. The specific capabilities of the modeler are described.
Higher sympathetic nerve activity during ventricular (VVI) than during dual-chamber (DDD) pacing
NASA Technical Reports Server (NTRS)
Taylor, J. A.; Morillo, C. A.; Eckberg, D. L.; Ellenbogen, K. A.
1996-01-01
OBJECTIVES: We determined the short-term effects of single-chamber ventricular pacing and dual-chamber atrioventricular (AV) pacing on directly measured sympathetic nerve activity. BACKGROUND: Dual-chamber AV cardiac pacing results in greater cardiac output and lower systemic vascular resistance than does single-chamber ventricular pacing. However, it is unclear whether these hemodynamic advantages result in less sympathetic nervous system outflow. METHODS: In 13 patients with a dual-chamber pacemaker, we recorded the electrocardiogram, noninvasive arterial pressure (Finapres), respiration and muscle sympathetic nerve activity (microneurography) during 3 min of underlying basal heart rate and 3 min of ventricular and AV pacing at rates of 60 and 100 beats/min. RESULTS: Arterial pressure was lowest and muscle sympathetic nerve activity was highest at the underlying basal heart rate. Arterial pressure increased with cardiac pacing and was greater with AV than with ventricular pacing (change in mean blood pressure +/- SE: 10 +/- 3 vs. 2 +/- 2 mm Hg at 60 beats/min; 21 +/- 5 vs. 14 +/- 2 mm Hg at 100 beats/min; p < 0.05). Sympathetic nerve activity decreased with cardiac pacing and the decline was greater with AV than with ventricular pacing (60 beats/min -40 +/- 11% vs. -17 +/- 7%; 100 beats/min -60 +/- 9% vs. -48 +/- 10%; p < 0.05). Although most patients showed a strong inverse relation between arterial pressure and muscle sympathetic nerve activity, three patients with severe left ventricular dysfunction (ejection fraction < or = 30%) showed no relation between arterial pressure and sympathetic activity. CONCLUSIONS: Short-term AV pacing results in lower sympathetic nerve activity and higher arterial pressure than does ventricular pacing, indicating that cardiac pacing mode may influence sympathetic outflow simply through arterial baroreflex mechanisms. We speculate that the greater incidence of adverse outcomes in patients treated with single-chamber ventricular
ERIC Educational Resources Information Center
Castellanos, Jeanett, Ed.; Jones, Lee, Ed.
This collection discusses various aspects of increasing the representation of Latinas and Latinos in U.S. higher education. The selections provide historical background, review issues of access and achievement, and present problems of status and barriers to success. The book opens with "Latina/o Undergraduate Experiences in American Higher…
Linear duals of graded bundles and higher analogues of (Lie) algebroids
NASA Astrophysics Data System (ADS)
Bruce, Andrew James; Grabowska, Katarzyna; Grabowski, Janusz
2016-03-01
Graded bundles are a class of graded manifolds which represent a natural generalisation of vector bundles and include the higher order tangent bundles as canonical examples. We present and study the concept of the linearisation of graded bundle which allows us to define the notion of the linear dual of a graded bundle. They are examples of double structures, graded-linear (GL) bundles, including double vector bundles as a particular case. On GL-bundles we define what we shall call weighted algebroids, which are to be understood as algebroids in the category of graded bundles. They can be considered as a geometrical framework for higher order Lagrangian mechanics. Canonical examples are reductions of higher tangent bundles of Lie groupoids. Weighted algebroids represent also a generalisation of VB-algebroids as defined by Gracia-Saz & Mehta and the LA-bundles of Mackenzie. The resulting structures are strikingly similar to Voronov's higher Lie algebroids, however our approach does not require the initial structures to be defined on supermanifolds.
"Engineered dual NbTa barriers for higher Jc Nb3Sn superconductors"
Robert E. Barber; Karl T. Hartwig
2012-07-07
The tantalum (Ta) diffusion barrier in advanced Nb3Sn superconductors often develops a failure mode during wire drawing where the Nb and Ta layers deform non-uniformly leading to a rough interface with adjacent copper. The non-uniform deformation of these layers can lead to premature wire breakage and breaches in the barrier, and contamination of the copper stabilizer by tin (Sn). The objective of the proposed work was to demonstrate that a dual NbTa layer made from severely deformed Nb and Ta exhibits improved co-deformation behavior with pure Cu in advanced Nb3Sn superconductors. This phase I project demonstrated improved microstructural uniformity and superior mechanical property characteristics of equal channel angular extrusion (ECAE) processed and rolled Nb and Ta sheets. The results of this work point to a method for fabrication of higher field and lower cost superconducting magnets for high energy physics applications.
ERIC Educational Resources Information Center
Touchstone, Allison J. L.
2010-01-01
Dual credit programs have become increasingly popular with 71% U.S. public high schools offering dual credit courses in 2002-2003. As this popularity has grown, so have concerns regarding academic rigor, course quality, parity with college courses, and effects on higher education. Determining actual dual credit course equivalent in higher…
Asian Pacific Americans in Higher Education: Faculty and Administrative Representation and Tenure.
ERIC Educational Resources Information Center
Nakanishi, Don T.
1993-01-01
Three prevalent misconceptions about Asian Pacific Americans in higher education are challenged, based on distribution data and documented tenure cases: that they are well represented in college faculties and key administrative positions, do not face discriminatory or unfair employment practices, and are less likely than others to contest…
ERIC Educational Resources Information Center
Suspitsyna, Tatiana
2015-01-01
This paper presents the results of a discourse analysis of the "Chronicle of Higher Education" publications about China in 2011 and 2012. Drawing on postcolonial appropriations of governmentality to frame the discussion of globalization as the context of the study, the author analyzes the stylistic, rhetorical, and semantic strategies…
Higher Education Policy Reform in Ethiopia: The Representation of the Problem of Gender Inequality
ERIC Educational Resources Information Center
Molla, Tebeje
2013-01-01
The higher education (HE) subsystem in Ethiopia has passed through a series of policy reforms in the last 10 years. Key reform areas ranged from improving quality and relevance of programmes to promoting equality in access to and success in HE. Despite the effort underway, gender inequality has remained a critical challenge in the subsystem. This…
ERIC Educational Resources Information Center
Tennyson, Robert D.
Educational experiences can now be an important element for people who want to obtain a college degree but were unable to because of the limited structure of traditional schools. This can be achieved through the nonresidential school in higher education that emphasizes student-environment interaction. If the nonresidential school is to be a…
ERIC Educational Resources Information Center
Ashwin, Paul; Abbas, Andrea; McLean, Monica
2015-01-01
This article examines the ways in which a high-quality system of undergraduate education is represented in recent policy documents from a range of actors interested in higher education. Drawing on Basil Bernstein's ideas, the authors conceptualise the policy documents as reflecting a struggle over competing views of quality that are expressed…
ERIC Educational Resources Information Center
Marcucci, Pamela; Johnstone, D. Bruce; Ngolovoi, Mary
2008-01-01
Three universal demands characterize higher education globally: the demand for higher quality, for increased access, and for greater equity. In East Africa, where resources are highly constrained, no nation has been able to meet these demands on the basis of public expenditures alone. Instead countries have had to increase resources from nonpublic…
Novel asymmetric representation method for solving the higher-order Ginzburg-Landau equation.
Wong, Pring; Pang, Lihui; Wu, Ye; Lei, Ming; Liu, Wenjun
2016-01-01
In ultrafast optics, optical pulses are generated to be of shorter pulse duration, which has enormous significance to industrial applications and scientific research. The ultrashort pulse evolution in fiber lasers can be described by the higher-order Ginzburg-Landau (GL) equation. However, analytic soliton solutions for this equation have not been obtained by use of existing methods. In this paper, a novel method is proposed to deal with this equation. The analytic soliton solution is obtained for the first time, and is proved to be stable against amplitude perturbations. Through the split-step Fourier method, the bright soliton solution is studied numerically. The analytic results here may extend the integrable methods, and could be used to study soliton dynamics for some equations in other disciplines. It may also provide the other way to obtain two-soliton solutions for higher-order GL equations. PMID:27086841
Novel asymmetric representation method for solving the higher-order Ginzburg-Landau equation
NASA Astrophysics Data System (ADS)
Wong, Pring; Pang, Lihui; Wu, Ye; Lei, Ming; Liu, Wenjun
2016-04-01
In ultrafast optics, optical pulses are generated to be of shorter pulse duration, which has enormous significance to industrial applications and scientific research. The ultrashort pulse evolution in fiber lasers can be described by the higher-order Ginzburg-Landau (GL) equation. However, analytic soliton solutions for this equation have not been obtained by use of existing methods. In this paper, a novel method is proposed to deal with this equation. The analytic soliton solution is obtained for the first time, and is proved to be stable against amplitude perturbations. Through the split-step Fourier method, the bright soliton solution is studied numerically. The analytic results here may extend the integrable methods, and could be used to study soliton dynamics for some equations in other disciplines. It may also provide the other way to obtain two-soliton solutions for higher-order GL equations.
Novel asymmetric representation method for solving the higher-order Ginzburg-Landau equation
Wong, Pring; Pang, Lihui; Wu, Ye; Lei, Ming; Liu, Wenjun
2016-01-01
In ultrafast optics, optical pulses are generated to be of shorter pulse duration, which has enormous significance to industrial applications and scientific research. The ultrashort pulse evolution in fiber lasers can be described by the higher-order Ginzburg-Landau (GL) equation. However, analytic soliton solutions for this equation have not been obtained by use of existing methods. In this paper, a novel method is proposed to deal with this equation. The analytic soliton solution is obtained for the first time, and is proved to be stable against amplitude perturbations. Through the split-step Fourier method, the bright soliton solution is studied numerically. The analytic results here may extend the integrable methods, and could be used to study soliton dynamics for some equations in other disciplines. It may also provide the other way to obtain two-soliton solutions for higher-order GL equations. PMID:27086841
NASA Technical Reports Server (NTRS)
Namburu, R. R.; Tamma, K. K.
1991-01-01
The applicability and evaluation of a generalized gamma(T) family of flux-based representations are examined for two different thermal analysis formulations for structures and materials which exhibit no phase change effects. The so-called H-theta and theta forms are demonstrated for numerous test models and linear and higher-order elements. The results show that the theta form with flux-based representations is generally superior to traditional approaches.
Dual Learning--A Challenge for Higher Education in the New Landscape of Governance
ERIC Educational Resources Information Center
Aili, Carola; Nilsson, Lars-Erik
2015-01-01
In many countries, practice-oriented programmes have been recast as university programmes, fuelling debate on the purpose of higher education. We highlight two ways of talking about the challenges for higher education we think are already familiar to readers. We label them "political-worry discourse" and "academic-worry…
Dual Mode Offering as Viable Approach for Promotion of Higher Education in Pakistan
ERIC Educational Resources Information Center
Hussain, Irshad
2014-01-01
Pakistan is a developing country with 148 universities and degree awarding institutions including public and private sector. The enrolment as given in the National Educational Policy 2009 was up to 5% only. It reflects greater demands of higher/tertiary education and calls for alternative strategic measures for addressing the issue. An innovative…
Lesaint, Florian; Sigaud, Olivier; Flagel, Shelly B; Robinson, Terry E; Khamassi, Mehdi
2014-02-01
Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs) and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US), some rats (sign-trackers) come to approach and engage the conditioned stimulus (CS) itself - a lever - more and more avidly, whereas other rats (goal-trackers) learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in computational
Lesaint, Florian; Sigaud, Olivier; Flagel, Shelly B.; Robinson, Terry E.; Khamassi, Mehdi
2014-01-01
Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs) and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US), some rats (sign-trackers) come to approach and engage the conditioned stimulus (CS) itself – a lever – more and more avidly, whereas other rats (goal-trackers) learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in
NASA Astrophysics Data System (ADS)
Li, Wen-long; Wang, Gang; Zhang, Gang; Pang, Chang-tao; Yin, Zhou-pin
2016-09-01
Onsite surface inspection with a touch probe or a laser scanner is a promising technique for efficiently evaluating surface profile error. The existing work of 5-axis inspection path generation bears a serious drawback, however, as there is a drastic orientation change of the inspection axis. Such a sudden change may exceed the stringent physical limit on the speed and acceleration of the rotary motions of the machine tool. In this paper, we propose a novel path generation method for onsite 5-axis surface inspection. The accessibility cones are defined and used to generate alternative interference-free inspection directions. Then, the control points are optimally calculated to obtain the dual-cubic non-Uniform rational B-splines (NURBS) curves, which respectively determine the path points and the axis vectors in an inspection path. The generated inspection path is smooth and non-interference, which deals with the ‘mutation and shake’ problems and guarantees a stable speed and acceleration of machine tool rotary motions. Its feasibility and validity is verified by the onsite inspection experiments of impeller blade.
Fan, Chao; Shi, Zhaomei; Pan, Yiting; Song, Zifeng; Zhang, Wanjun; Zhao, Xinyuan; Tian, Fang; Peng, Bo; Qin, Weijie; Cai, Yun; Qian, Xiaohong
2014-02-01
In an age of whole-genome analysis, the mass spectrometry-based bottom-up strategy is now considered to be the most powerful method for in-depth proteomics analysis. As part of this strategy, highly efficient and complete proteolytic digestion of proteins into peptides is crucial for successful proteome profiling with deep coverage. To achieve this goal, prolonged digestion time and the use of multiple proteases have been adopted. The long digestion time required and tedious sample treatment steps severely limit the sample processing throughput. Though utilization of immobilized protease greatly reduces the digestion time, highly efficient proteolysis of extremely complex proteomic samples remains a challenging task. Here, we propose a dual matrix-based complementary digestion method using two types of immobilized trypsin with opposite matrix hydrophobicity prepared by attaching trypsin on hydrophobic or hydrophilic polymer-brush-modified nanoparticles. The polymer brushes on the nanoparticles serve as three-dimensional supports for a large amount of trypsin immobilization and lead to ultrafast and highly efficient protein digestion. More importantly, the two types of immobilized trypsin show high complementarity in protein digestion with only ∼60% overlap in peptide identification for yeast and membrane protein of mouse liver. Complementary digestion by applying these two types of immobilized trypsin together leads to obviously enhanced protein and peptide identification. Furthermore, the dual matrix-based complementary digestion shows particular advantage in the digestion of membrane proteins, as twice the number of identified peptides is obtained compared with solution digestion using free proteases, demonstrating its potential as a promising alternative to promote proteomics analysis with higher protein sequence coverage. PMID:24447065
ERIC Educational Resources Information Center
Addessi, Anna Rita; Carugati, Felice
2010-01-01
This paper deals with an empirical study undertaken at the University of Bologna about the social representations of music held by university students studying to become teachers in nursery, kindergarten and primary education. An open questionnaire was submitted to the university students at the beginning and end of the music education teaching…
NASA Astrophysics Data System (ADS)
Athenodorou, Andreas; Teper, Michael
2013-06-01
We calculate, numerically, the low-lying spectrum of closed confining flux tubes that carry flux in different representations of SU( N). We do so for SU(6) at β = 171, where the calculated low-energy physics is very close to the continuum limit and, in many respects, also close to N = ∞. We focus on the adjoint, 84, 120, k = 2 A, 2 S and k = 3 A,3 M,3 S representations and provide evidence that the corresponding flux tubes, albeit mostly unstable, do in fact exist. We observe that the ground state of a flux tube with momentum along its axis appears to be well defined in all cases and is well described by the Nambu-Goto spectrum (in flat space-time), all the way down to very small lengths, just as it is for flux tubes carrying fundamental flux. Excited states, however, typically show very much larger deviations from Nambu-Goto than the corresponding excitations of fundamental flux tubes and, indeed, cannot be extracted in many cases. We discuss whether what we are seeing here are separate stringy and massive modes or simply large corrections to energy levels that will become string-like at larger lengths.
ERIC Educational Resources Information Center
Bótas, Paulo Charles Pimentel; Huisman, Jeroen
2012-01-01
This article explores how power relations are constructed in the governance of higher education institutions. It examines and deconstructs, from a Foucauldian perspective, power relations and mechanisms in the relationship between the state and higher education institutions, and between academic and management staff. This research article…
ERIC Educational Resources Information Center
Carey, Philip
2013-01-01
Student engagement is increasingly part of higher education rhetoric. It is seen as a means for universities to understand and enhance the student experience. This has been prompted by a number of potentially conflicting factors. These include growing consumerism in higher education, the rise of user involvement and the notion of students as…
ERIC Educational Resources Information Center
Toynton, Robert
2007-01-01
A group of science students self-identifying as gay or queer have only talked of their sexuality and gender feelings, and their experiences within higher education, on the completion of their studies. The reasons for their alienation from, and further marginalisation by the queer discourse are discussed. These include the stereotyping of gay…
Pop, Marcel; Hollós, Sándor; Vingender, István; Mészáros, Judit
2009-03-01
Our paper is presenting a new initiative regarding an international cooperation willing to develop a dual degree program in nursing, the so-called Transatlantic Curriculum in Nursing. The candidates--after successful completion of their studies--will get a European and an American partner diploma in nursing. The objective is to prepare an internationally and culturally competent workforce; develop the practice of nursing students' exchange programs; process the model of dual degree independent of geographical, political or cultural borders; spread the evidence-based nursing standards in the daily practice. The partners in this initiative are Semmelweis University in Budapest, Hungary, Nazareth College of Rochester, NY, USA and Laurea University in Tikkurila, Finland. The planned activities in the framework of the program: mutual student and staff mobility, joint curriculum development and teaching process, determining joint standards. The expected outcomes are: to develop a standardised model for the enhancement and implementation of international educational programs in nursing; to improve institutional work culture; to improve professional terminology and cultural abilities; to create the model of a new type of nursing professional having a high level of cultural and language competence which are indispensable for participating in global programs. PMID:19240013
Zhao, Xin-Cheng; Kvello, Pål; Løfaldli, Bjarte B.; Lillevoll, Siri C.; Mustaparta, Hanna; Berg, Bente G.
2014-01-01
The arrangement of anatomically separated systems for information about general and pheromone odorants is well documented at the initial levels of the olfactory pathway both in vertebrates and insects. In the primary olfactory center of the moth brain, for example, a few enlarged glomeruli situated dorsally, at the entrance of the antennal nerve, are devoted to information about female-produced substances whereas a set of more numerous ordinary glomeruli (OG) receives input about general odorants. Heliothine moths are particularly suitable for studying central chemosensory mechanisms not only because of their anatomically separated systems for plant odors and pheromones but also due to their use of female-produced substances in communication across the species. Thus, the male-specific system of heliothine moths includes two sub-arrangements, one ensuring attraction and mating behavior by carrying information about pheromones released by conspecifics, and the other inhibition of attraction via signal information emitted from heterospecifics. Based on previous tracing experiments, a general chemotopic organization of the male-specific glomeruli has been demonstrated in a number of heliothine species. As compared to the well explored organization of the moth antennal lobe (AL), demonstrating a non-overlapping representation of the biologically relevant stimuli, less is known about the neural arrangement residing at the following synaptic level, i.e., the mushroom body calyces and the lateral horn. In the study presented here, we have labeled physiologically characterized antennal-lobe projection neurons in males of the two heliothine species, Heliothis virescens and Helicoverpa assulta, for the purpose of mapping their target regions in the protocerebrum. In order to compare the representation of plant odors, pheromones, and interspecific signals in the higher brain regions of each species, we have created standard brain atlases and registered three-dimensional models
Araoz, Philip A.; Kirsch, Jacobo; Primak, Andrew N.; Braun, Natalie N.; Saba, Osama; Williamson, Eric E.; Harmsen, W. Scott; Mandrekar, Jayawant N.; McCollough, Cynthia H.
2010-01-01
Objective To compare coronary image quality at temporal resolutions associated with dual-source computed tomography (DSCT; 83 milliseconds) and 64–detector row scanning (165 milliseconds). Methods In 30 patients with a heart rate of less than 70 beats per minute, DSCT coronary angiograms were reconstructed at 83- and 165-millisecond temporal resolutions over different cardiac phases. A blinded observer graded coronary quality. Results The typical DSCT temporal resolution (83 milliseconds) showed a significantly greater quality at end-systole for all coronary vessels and at end-diastole for the right coronary and left anterior descending coronary arteries. For all vessels, the end-diastole produced the highest quality for both temporal resolutions. Conclusions Imaging at 83 milliseconds creates superior quality at end-systole for all coronary vessels and at end-diastole for the right coronary and left anterior descending coronary arteries. At low heart rates, end-diastole produces the highest quality at both temporal resolutions. PMID:20118724
Silverman, Lewis R; Greenberg, Peter; Raza, Azra; Olnes, Matthew J; Holland, James F; Reddy, Premkumar; Maniar, Manoj; Wilhelm, Francois
2015-06-01
Rigosertib (ON 01910.Na) is an inhibitor of the phosphoinositide 3-kinase and polo-like kinase pathways that induces mitotic arrest and apoptosis in neoplastic cells, while sparing normal cells. Our purpose is to summarize the clinical activity and safety of intravenous (IV) rigosertib delivered by an external ambulatory infusion pump in patients with refractory anemia with excess blasts-1, -2, or, -t myelodysplastic syndromes (MDS) following prior treatment with DNA methyltransferase (DNMT) inhibitors. A total of 39 patients with MDS who fulfilled these criteria were enrolled in four phase 1-2 clinical trials of IV rigosertib. Thirty five (88%) had higher risk disease according to the Revised International Prognostic Scoring System. Median overall survival for this group of 39 patients was 35 weeks. Of 30 evaluable patients with follow-up bone marrow biopsies, 12 (40%) achieved complete (n = 5) or partial (n = 7) bone marrow blast responses. In addition, 15 patients achieved stabilization of bone marrow blasts. One patient with a complete bone marrow response also achieved a complete cytogenetic response. A second patient with stable bone marrow blasts achieved a partial cytogenetic response. Two of the responding patients and three patients with stable disease had hematological improvements. Rigosertib-induced bone marrow blast decreases and stability appeared to be predictive of prolonged survival. IV rigosertib had a favorable safety profile without significant myelosuppression. Most common drug-related toxicities included fatigue, diarrhea, nausea, dysuria, and hematuria. In summary, IV rigosertib is well tolerated and has clinical activity in patients with higher risk MDS following DNMT inhibitor treatment. A multinational pivotal phase 3 randomized clinical trial of rigosertib versus best supportive care for patients with MDS with excess blasts following prior treatment with DNMT inhibitors (ONTIME: ON 01910.Na Trial In Myelodysplastic SyndromE) has recently
Atypical language representation in children with intractable temporal lobe epilepsy.
Maulisova, Alice; Korman, Brandon; Rey, Gustavo; Bernal, Byron; Duchowny, Michael; Niederlova, Marketa; Krsek, Pavel; Novak, Vilem
2016-05-01
This study evaluated language organization in children with intractable epilepsy caused by temporal lobe focal cortical dysplasia (FCD) alone or dual pathology (temporal lobe FCD and hippocampal sclerosis, HS). We analyzed clinical, neurological, fMRI, neuropsychological, and histopathologic data in 46 pediatric patients with temporal lobe lesions who underwent excisional epilepsy surgery. The frequency of atypical language representation was similar in both groups, but children with dual pathology were more likely to be left-handed. Atypical receptive language cortex correlated with lower intellectual capacity, verbal abstract conceptualization, receptive language abilities, verbal working memory, and a history of status epilepticus but did not correlate with higher seizure frequency or early seizure onset. Histopathologic substrate had only a minor influence on neuropsychological status. Greater verbal comprehension deficits were noted in children with atypical receptive language representation, a risk factor for cognitive morbidity. PMID:27064828
Givati, Assaf; Hatton, Kieron
2015-04-01
Traditional acupuncturists' quest for external legitimacy in Britain involves the standardization of their knowledge bases through the development of training schools and syllabi, formal educational structures, and, since the 1990s, the teaching of undergraduate courses within (or validated by) Higher Education Institutions (HEIs), a process which entails biomedical alignment of the curriculum. However, as holistic discourses were commonly used as a rhetorical strategy by CAM practitioners to distance themselves from biomedicine and as a source of public appeal, this 'mainstreaming' process evoked practitioners' concerns that their holistic claims are being compromised. An additional challenge is being posed by a group of academics and scientists in Britain who launched an attack on CAM courses taught in HEIs, accusing them of being 'unscientific' and 'non-academic' in nature. This paper explores the negotiation of all these challenges during the formalization of traditional acupuncture education in Britain, with a particular focus on the role of HEIs. The in-depth qualitative investigation draws on several data sets: participant observation in a university validated acupuncture course; in-depth interviews; and documentary analysis. The findings show how, as part of the formalization process, acupuncturists in Britain (re)negotiate their holistic, anti-reductionist discourses and claims in relation to contemporary societal, political and cultural forces. Moreover, the teaching and validation of acupuncture courses by HEIs may contribute to broadening acupuncturists' 'holistic awareness' of societal and cultural influences on individuals' and communities' ill-health. This investigation emphasises the dynamic and context-specific (rather than fixed and essentialized) nature of acupuncture practice and knowledge. PMID:25779622
ERIC Educational Resources Information Center
Schultz, James E.; Waters, Michael S.
2000-01-01
Discusses representations in the context of solving a system of linear equations. Views representations (concrete, tables, graphs, algebraic, matrices) from perspectives of understanding, technology, generalization, exact versus approximate solution, and learning style. (KHR)
Valla, Jeffrey M; Williams, Wendy M
2012-01-01
The under-representation of women and ethnic minorities in Science, Technology, Engineering, and Mathematics (STEM) education and professions has resulted in a loss of human capital for the US scientific workforce and spurred the development of myriad STEM educational intervention programs. Increased allocation of resources to such programs begs for a critical, prescriptive, evidence-based review that will enable researchers to develop optimal interventions and administrators to maximize investments. We begin by providing a theoretical backdrop for K-12 STEM programs by reviewing current data on under-representation and developmental research describing individual-level social factors undergirding these data. Next, we review prototypical designs of these programs, highlighting specific programs in the literature as examples of program structures and components currently in use. We then evaluate these interventions in terms of overall effectiveness, as a function of how well they address age-, ethnicity-, or gender-specific factors, suggesting improvements in program design based on these critiques. Finally, program evaluation methods are briefly reviewed and discussed in terms of how their empirical soundness can either enable or limit our ability to delineate effective program components. "Now more than ever, the nation's changing demographics demand that we include all of our citizens in science and engineering education and careers. For the U.S. to benefit from the diverse talents of all its citizens, we must grow the pipeline of qualified, underrepresented minority engineers and scientists to fill positions in industry and academia."-Irving P. McPhail.. PMID:22942637
Gabor representation with oversampling
NASA Astrophysics Data System (ADS)
Zibulski, Meir; Zeevi, Yehoshua Y.
1992-11-01
An approach for characterizing the properties of the basis functions of the Gabor representation in the context of oversampling is presented. The approach is based on the concept of frames and utilizes the Piecewise Zak Transform (PZT). The frame operator associated with the Gabor-type frame, the so-called Weyl-Heisenberg frame, is examined for a rational oversampling rate by representing the frame operator as a matrix-valued function in the PZT domain. Completeness and frame properties of the Gabor representation functions are examined in relation to the properties of the matrix-valued function. The frame bounds are calculated by means of the eigenvalues of the matrix-valued function, and the dual-frame, which is used in calculation of the expansion coefficients, is expressed by means of the inverse matrix.
Valla, Jeffrey M.; Williams, Wendy M.
2012-01-01
The under-representation of women and ethnic minorities in Science, Technology, Engineering, and Mathematics (STEM) education and professions has resulted in a loss of human capital for the US scientific workforce and spurred the development of myriad STEM educational intervention programs. Increased allocation of resources to such programs begs for a critical, prescriptive, evidence-based review that will enable researchers to develop optimal interventions and administrators to maximize investments. We begin by providing a theoretical backdrop for K-12 STEM programs by reviewing current data on under-representation and developmental research describing individual-level social factors undergirding these data. Next, we review prototypical designs of these programs, highlighting specific programs in the literature as examples of program structures and components currently in use. We then evaluate these interventions in terms of overall effectiveness, as a function of how well they address age-, ethnicity-, or gender-specific factors, suggesting improvements in program design based on these critiques. Finally, program evaluation methods are briefly reviewed and discussed in terms of how their empirical soundness can either enable or limit our ability to delineate effective program components. “Now more than ever, the nation’s changing demographics demand that we include all of our citizens in science and engineering education and careers. For the U.S. to benefit from the diverse talents of all its citizens, we must grow the pipeline of qualified, underrepresented minority engineers and scientists to fill positions in industry and academia.”—Irving P. McPhail.. PMID:22942637
Dual Enrollment Academy Programs
ERIC Educational Resources Information Center
Gonzalez, Nicolas; Chavez, Guadalupe
2009-01-01
Dual Enrollment Engineering (DEEA) and Medical Science (DEMSA) Academies are two-year dual enrollment programs for high school students. Students explore engineering and medical careers through college coursework. Students prepare for higher education in engineering and medical fields while completing associate degrees in biology or engineering…
ERIC Educational Resources Information Center
Manning, Sabine, Ed.
This document is the second report on results achieved in the project, "The Acquisition of Integrated Qualifications for Professional Work and Study--An Assessment of Innovative Approaches in Seven European Countries (INTEQUAL)," which was undertaken to identify innovative approaches to granting dual qualifications that can ultimately increase the…
ERIC Educational Resources Information Center
Hubain, Bryan S.; Allen, Evette L.; Harris, Jessica C.; Linder, Chris
2016-01-01
In this paper, we employ Critical Race Theory theoretically and methodologically to examine the racialized experiences of students of color in higher education and student affairs (HESA) graduate preparation programs. We employ counter-storytelling as a method for constructing narratives that disrupt the master narrative found within HESA graduate…
Representation is representation of similarities.
Edelman, S
1998-08-01
Advanced perceptual systems are faced with the problem of securing a principled (ideally, veridical) relationship between the world and its internal representation. I propose a unified approach to visual representation, addressing the need for superordinate and basic-level categorization and for the identification of specific instances of familiar categories. According to the proposed theory, a shape is represented internally by the responses of a small number of tuned modules, each broadly selective for some reference shape, whose similarity to the stimulus it measures. This amounts to embedding the stimulus in a low-dimensional proximal shape space spanned by the outputs of the active modules. This shape space supports representations of distal shape similarities that are veridical as Shepard's (1968) second-order isomorphisms (i.e., correspondence between distal and proximal similarities among shapes, rather than between distal shapes and their proximal representations). Representation in terms of similarities to reference shapes supports processing (e.g., discrimination) of shapes that are radically different from the reference ones, without the need for the computationally problematic decomposition into parts required by other theories. Furthermore, a general expression for similarity between two stimuli, based on comparisons to reference shapes, can be used to derive models of perceived similarity ranging from continuous, symmetric, and hierarchical ones, as in multidimensional scaling (Shepard 1980), to discrete and nonhierarchical ones, as in the general contrast models (Shepard & Arabie 1979; Tversky 1977). PMID:10097019
ERIC Educational Resources Information Center
Kuntz, Aaron M.
2010-01-01
What can be known and how to render what we know are perpetual quandaries met by qualitative research, complicated further by the understanding that the everyday discourses influencing our representations are often tacit, unspoken or heard so often that they seem to warrant little reflection. In this article, I offer analytic memos as a means for…
Active maintenance of semantic representations.
Nishiyama, Ryoji
2014-12-01
In research on verbal working memory, articulatory rehearsal, a maintenance mechanism for phonological representations, has undergone intensive and excellent study. Possible mechanisms for semantic representation have received less attention. However, several studies have reported a double dissociation in types of memory deficits (semantic memory difficulties vs. phonological memory difficulties). This suggests the separability of two maintenance mechanisms. The present study focused on this separability in individuals with normal memory abilities, using a dual-task interference paradigm. The results indicate a crossover interaction between memory and interference task effects: Preventing articulatory rehearsal more strongly disrupted the phonological memory task, whereas performing a tapping task that interfered with attentional control more strongly disrupted semantic memory. These results suggest that semantic representations are actively maintained by a mechanism other than phonological maintenance. PMID:24687734
Sparse representation of complex MRI images.
Nandakumar, Hari Prasad; Ji, Jim
2008-01-01
Sparse representation of images acquired from Magnet Resonance Imaging (MRI) has several potential applications. MRI is unique in that the raw images are complex. Complex wavelet transforms (CWT) can be used to produce flexible signal representations when compared to Discrete Wavelet Transform (DWT). In this work, five different schemes using CWT or DWT are tested for sparse representation of MRI images which are in the form of complex values, separate real/imaginary, or separate magnitude/phase. The experimental results on real in-vivo MRI images show that appropriate CWT, e.g., dual-tree CWT (DTCWT), can achieve sparsity better than DWT with similar Mean Square Error. PMID:19162677
Classification of non-coding RNA using graph representations ofsecondary structure
Karklin, Yan; Meraz, Richard F.; Holbrook, Stephen R.
2004-06-07
Some genes produce transcripts that function directly in regulatory, catalytic, or structural roles in the cell. These non-coding RNAs are prevalent in all living organisms, and methods that aid the understanding of their functional roles are essential. RNA secondary structure, the pattern of base-pairing, contains the critical information for determining the three dimensional structure and function of the molecule. In this work we examine whether the basic geometric and topological properties of secondary structure are sufficient to distinguish between RNA families in a learning framework. First, we develop a labeled dual graph representation of RNA secondary structure by adding biologically meaningful labels to the dual graphs proposed by Gan et al [1]. Next, we define a similarity measure directly on the labeled dual graphs using the recently developed marginalized kernels [2]. Using this similarity measure, we were able to train Support Vector Machine classifiers to distinguish RNAs of known families from random RNAs with similar statistics. For 22 of the 25 families tested, the classifier achieved better than 70% accuracy, with much higher accuracy rates for some families. Training a set of classifiers to automatically assign family labels to RNAs using a one vs. all multi-class scheme also yielded encouraging results. From these initial learning experiments, we suggest that the labeled dual graph representation, together with kernel machine methods, has potential for use in automated analysis and classification of uncharacterized RNA molecules or efficient genome-wide screens for RNA molecules from existing families.
Recchia-Luciani, Angelo N M
2012-04-01
The present paper proposes a definition for the complex polysemic concepts of consciousness and awareness (in humans as well as in other species), and puts forward the idea of a progressive ontological development of consciousness from a state of 'childhood' awareness, in order to explain that humans are not only able to manipulate objects, but also their mental representations. The paper builds on the idea of qualia intended as entities posing regular invariant requests to neural processes, trough the permanence of different properties. The concept of semantic differential introduces the properties of metaphorical qualia as an exclusively human ability. Furthermore this paper proposes a classification of qualia, according to the models-with different levels of abstraction-they are implied in, in a taxonomic perspective. This, in turn, becomes a source of categorization of divergent representations, sign systems, and forms of intentionality, relying always on biological criteria. New emerging image-of-the-world-devices are proposed, whose qualia are likely to be only accessible to humans: emotional qualia, where emotion accounts for the invariant and dominant property; and the qualic self where continuity, combined with the oneness of the self, accounts for the invariant and dominant property. The concept of congruence between different domains in a metaphor introduces the possibility of a general evaluation of truth and falsity of all kinds of metaphorical constructs, while the work of Matte Blanco enables us to classify conscious versus unconscious metaphors, both in individuals and in social organizations. PMID:22347988
NASA Astrophysics Data System (ADS)
Bergshoeff, Eric A.; Hohm, Olaf; Penas, Victor A.; Riccioni, Fabio
2016-06-01
We present the dual formulation of double field theory at the linearized level. This is a classically equivalent theory describing the duals of the dilaton, the Kalb-Ramond field and the graviton in a T-duality or O( D, D) covariant way. In agreement with previous proposals, the resulting theory encodes fields in mixed Young-tableau representations, combining them into an antisymmetric 4-tensor under O( D, D). In contrast to previous proposals, the theory also requires an antisymmetric 2-tensor and a singlet, which are not all pure gauge. The need for these additional fields is analogous to a similar phenomenon for "exotic" dualizations, and we clarify this by comparing with the dualizations of the component fields. We close with some speculative remarks on the significance of these observations for the full non-linear theory yet to be constructed.
Dual isomonodromic deformations and moment maps to loop algebras
NASA Astrophysics Data System (ADS)
Harnad, J.
1994-12-01
The Hamiltonian structure of the monodromy preserving deformation equations of Jimbo et al [JMMS] is explained in terms of parameter dependent pairs of moment maps from a symplectic vector space to the dual spaces of two different loop algebras. The nonautonomous Hamiltonian systems generating the deformations are obtained by pulling back spectral invariants on Poisson subspaces consisting of elements that are rational in the loop parameter and identifying the deformation parameters with those determining the moment maps. This construction is shown to lead to “dual” pairs of matrix differential operators whose monodromy is preserved under the same family of deformations. As illustrative examples, involving discrete and continuous reductions, a higher rank generalization of the Hamiltonian equations governing the correlation functions for an impenetrable Bose gas is obtained, as well as dual pairs of isomonodromy representations for the equations of the Painlevé transcendents P V and VI .
The Representation of Abstract Words: Why Emotion Matters
ERIC Educational Resources Information Center
Kousta, Stavroula-Thaleia; Vigliocco, Gabriella; Vinson, David P.; Andrews, Mark; Del Campo, Elena
2011-01-01
Although much is known about the representation and processing of concrete concepts, knowledge of what abstract semantics might be is severely limited. In this article we first address the adequacy of the 2 dominant accounts (dual coding theory and the context availability model) put forward in order to explain representation and processing…
NASA Astrophysics Data System (ADS)
Koma, Y.; Koma (Takayama), M.
2003-01-01
The ratios between the string tensions σ_D of color-electric flux tubes in higher and fundamental SU(3) representations, dD equiv σD/σ3, are systematically studied in a Weyl symmetric formulation of the DGL theory. The ratio is found to depend on the Ginzburg-Landau (GL) parameter, kappa equiv m_{χ}/mB, the mass ratio between the monopoles (m_{χ}) and the masses of the dual gauge bosons (mB). While the ratios dD follow a simple flux counting rule in the Bogomol'nyi limit, kappa=1.0, systematic deviations appear with increasing kappa due to interactions between the fundamental flux inside a higher representation flux tube. We find that in a type-II dual superconducting vacuum near kappa = 3.0 this leads to a consistent description of the ratios dD as observed in lattice QCD simulations.
Technology Transfer Automated Retrieval System (TEKTRAN)
Targhee Russet is a dark-skinned russet potato variety with tubers slightly longer than Russet Burbank. It produces higher total and marketable yields than does Russet Burbank at most of the sites it was tested in the western United States. Tuber dormancy is about 58 days shorter than Russet Burba...
ERIC Educational Resources Information Center
Hoareau, Cecile
2011-01-01
The French Government has had a paradoxical relationship with globalization. Globalization is perceived as both a threat to react against and a cradle for new policy ideas. French policymakers have a love-hate relationship with the European higher education reforms that started in the 1990s, a mixed sentiment that French singer Serge Gainsbourg…
Attentional Control via Parallel Target-Templates in Dual-Target Search
Barrett, Doug J. K.; Zobay, Oliver
2014-01-01
Simultaneous search for two targets has been shown to be slower and less accurate than independent searches for the same two targets. Recent research suggests this ‘dual-target cost’ may be attributable to a limit in the number of target-templates than can guide search at any one time. The current study investigated this possibility by comparing behavioural responses during single- and dual-target searches for targets defined by their orientation. The results revealed an increase in reaction times for dual- compared to single-target searches that was largely independent of the number of items in the display. Response accuracy also decreased on dual- compared to single-target searches: dual-target accuracy was higher than predicted by a model restricting search guidance to a single target-template and lower than predicted by a model simulating two independent single-target searches. These results are consistent with a parallel model of dual-target search in which attentional control is exerted by more than one target-template at a time. The requirement to maintain two target-templates simultaneously, however, appears to impose a reduction in the specificity of the memory representation that guides search for each target. PMID:24489793
NASA Astrophysics Data System (ADS)
Nichols, Kim; Gillies, Robyn; Hedberg, John
2016-06-01
This study explored the impact of argumentation-promoting collaborative inquiry and representational work in science on primary students' representational fluency. Two hundred sixty-six year 6 students received instruction on natural disasters with a focus on collaborative inquiry. Students in the Comparison condition received only this instruction. Students in the Explanation condition were also instructed with a focus on explanations using representations. Students in the Argumentation condition received similar instruction to the Comparison and Explanation conditions but were also instructed with a focus on argumentation using representations. Conceptual understanding and representational competencies (interpreting, explaining and constructing representations) were measured prior to and immediately following the instruction. A small group collaborative representational task was video recorded at the end of the instruction and coded for modes of knowledge-building discourse; knowledge-sharing and knowledge-construction. Higher measures of conceptual understanding, representational competencies and knowledge-construction discourse were taken together as representational fluency. Students in all conditions showed significant improvement in conceptual understanding, interpreting representations and explaining representations. Students in the Comparison and Argumentation conditions also showed significantly improved scores in constructing representations. When compared to the other conditions, the Explanation group had the highest scores in conceptual understanding and also interpreting and explaining representations. While the Argumentation group had the highest scores for constructing representations, their scores for conceptual understanding as well as interpreting and explaining representations were also high. There was no difference between the groups in knowledge-sharing discourse; however, the Argumentation group displayed the highest incidence of knowledge
Computer aided surface representation
Barnhill, R.E.
1990-02-19
The central research problem of this project is the effective representation, computation, and display of surfaces interpolating to information in three or more dimensions. If the given information is located on another surface, then the problem is to construct a surface defined on a surface''. Sometimes properties of an already defined surface are desired, which is geometry processing''. Visualization of multivariate surfaces is possible by means of contouring higher dimensional surfaces. These problems and more are discussed below. The broad sweep from constructive mathematics through computational algorithms to computer graphics illustrations is utilized in this research. The breadth and depth of this research activity makes this research project unique.
L1 and L2 Picture Naming in Mandarin-English Bilinguals: A Test of Bilingual Dual Coding Theory
ERIC Educational Resources Information Center
Jared, Debra; Poh, Rebecca Pei Yun; Paivio, Allan
2013-01-01
This study examined the nature of bilinguals' conceptual representations and the links from these representations to words in L1 and L2. Specifically, we tested an assumption of the Bilingual Dual Coding Theory that conceptual representations include image representations, and that learning two languages in separate contexts can result in…
Sparse representation with kernels.
Gao, Shenghua; Tsang, Ivor Wai-Hung; Chia, Liang-Tien
2013-02-01
Recent research has shown the initial success of sparse coding (Sc) in solving many computer vision tasks. Motivated by the fact that kernel trick can capture the nonlinear similarity of features, which helps in finding a sparse representation of nonlinear features, we propose kernel sparse representation (KSR). Essentially, KSR is a sparse coding technique in a high dimensional feature space mapped by an implicit mapping function. We apply KSR to feature coding in image classification, face recognition, and kernel matrix approximation. More specifically, by incorporating KSR into spatial pyramid matching (SPM), we develop KSRSPM, which achieves a good performance for image classification. Moreover, KSR-based feature coding can be shown as a generalization of efficient match kernel and an extension of Sc-based SPM. We further show that our proposed KSR using a histogram intersection kernel (HIK) can be considered a soft assignment extension of HIK-based feature quantization in the feature coding process. Besides feature coding, comparing with sparse coding, KSR can learn more discriminative sparse codes and achieve higher accuracy for face recognition. Moreover, KSR can also be applied to kernel matrix approximation in large scale learning tasks, and it demonstrates its robustness to kernel matrix approximation, especially when a small fraction of the data is used. Extensive experimental results demonstrate promising results of KSR in image classification, face recognition, and kernel matrix approximation. All these applications prove the effectiveness of KSR in computer vision and machine learning tasks. PMID:23014744
and as Vertex Operator Extensionsof Dual Affine Algebras
NASA Astrophysics Data System (ADS)
Bowcock, P.; Feigin, B. L.; Semikhatov, A. M.; Taormina, A.
We discover a realisation of the affine Lie superalgebra and of the exceptional affine superalgebra as vertex operator extensions of two algebras with ``dual'' levels (and an auxiliary level-1 algebra). The duality relation between the levels is . We construct the representation of on a sum of tensor products of , , and modules and decompose it into a direct sum over the spectral flow orbit. This decomposition gives rise to character identities, which we also derive. The extension of the construction to is traced to the properties of embeddings into and their relation with the dual pairs. Conversely, we show how the representations are constructed from representations.
ERIC Educational Resources Information Center
Rumelhart, David E.; Norman, Donald A.
This paper reviews work on the representation of knowledge from within psychology and artificial intelligence. The work covers the nature of representation, the distinction between the represented world and the representing world, and significant issues concerned with propositional, analogical, and superpositional representations. Specific topics…
Contractions of the irreducible representations of the quantum algebras suq(2) and soq(3)
NASA Astrophysics Data System (ADS)
Gromov, N. A.; Man'ko, V. I.
1992-04-01
The contractions of the irreducible representations of the unitary quantum algebra suq(2) and the orthogonal quantum algebra soq(3) in the Gel'fand-Tsetlin basis are regarded in detail with the help of the dual numbers.
Computer aided surface representation
Barnhill, R.E.
1991-04-02
Modern computing resources permit the generation of large amounts of numerical data. These large data sets, if left in numerical form, can be overwhelming. Such large data sets are usually discrete points from some underlying physical phenomenon. Because we need to evaluate the phenomenon at places where we don't have data, a continuous representation (a surface'') is required. A simple example is a weather map obtained from a discrete set of weather stations. (For more examples including multi-dimensional ones, see the article by Dr. Rosemary Chang in the enclosed IRIS Universe). In order to create a scientific structure encompassing the data, we construct an interpolating mathematical surface which can evaluate at arbitrary locations. We can also display and analyze the results via interactive computer graphics. In our research we construct a very wide variety of surfaces for applied geometry problems that have sound theoretical foundations. However, our surfaces have the distinguishing feature that they are constructed to solve short or long term practical problems. This DOE-funded project has developed the premiere research team in the subject of constructing surfaces (3D and higher dimensional) that provide smooth representations of real scientific and engineering information, including state of the art computer graphics visualizations. However, our main contribution is in the development of fundamental constructive mathematical methods and visualization techniques which can be incorporated into a wide variety of applications. This project combines constructive mathematics, algorithms, and computer graphics, all applied to real problems. The project is a unique resource, considered by our peers to be a de facto national center for this type of research.
Pedagogical Affordances of Multiple External Representations in Scientific Processes
ERIC Educational Resources Information Center
Wu, Hsin-Kai; Puntambekar, Sadhana
2012-01-01
Multiple external representations (MERs) have been widely used in science teaching and learning. Theories such as dual coding theory and cognitive flexibility theory have been developed to explain why the use of MERs is beneficial to learning, but they do not provide much information on pedagogical issues such as how and in what conditions MERs…
R. KELSEY
2001-02-01
For focused applications with limited user and use application communities, XML can be the right choice for representation. It is easy to use, maintain, and extend and enjoys wide support in commercial and research sectors. When the knowledge and information to be represented is object-based and use of that knowledge and information is a high priority, then XML-based representation should be considered. This paper discusses some of the issues involved in using XML-based representation and presents an example application that successfully uses an XML-based representation.
ERIC Educational Resources Information Center
Dick, Anthony Steven; Overton, Willis F.; Kovacs, Stacie L.
2005-01-01
Children's developing competence with symbolic representations was assessed in 3 studies. Study 1 examined the hypothesis that the production of imaginary symbolic objects in pantomime requires the simultaneous coordination of the dual representations of a dynamic action and a symbolic object. We explored this coordination of symbolic…
Hologram representation of design data in an expert system knowledge base
NASA Technical Reports Server (NTRS)
Shiva, S. G.; Klon, Peter F.
1988-01-01
A novel representational scheme for design object descriptions is presented. An abstract notion of modules and signals is developed as a conceptual foundation for the scheme. This abstraction relates the objects to the meaning of system descriptions. Anchored on this abstraction, a representational model which incorporates dynamic semantics for these objects is presented. This representational model is called a hologram scheme since it represents dual level information, namely, structural and semantic. The benefits of this scheme are presented.
Inscriptions Becoming Representations in Representational Practices
ERIC Educational Resources Information Center
Medina, Richard; Suthers, Daniel
2013-01-01
We analyze the interaction of 3 students working on mathematics problems over several days in a virtual math team. Our analysis traces out how successful collaboration in a later session is contingent upon the work of prior sessions and shows how the development of representational practices is an important aspect of these participants' problem…
Reading Visual Representations
ERIC Educational Resources Information Center
Rubenstein, Rheta N.; Thompson, Denisse R.
2012-01-01
Mathematics is rich in visual representations. Such visual representations are the means by which mathematical patterns "are recorded and analyzed." With respect to "vocabulary" and "symbols," numerous educators have focused on issues inherent in the language of mathematics that influence students' success with mathematics communication.…
Dual instantons in antimembranes theory
Imaanpur, A.; Naghdi, M.
2011-04-15
We introduce two ansatzs for the 3-form potential of Euclidean 11d supergravity on skew-whiffed AdS{sub 4}xS{sup 7} background which results in two scalar modes with m{sup 2}=-2 on AdS{sub 4}. Being conformally coupled with a quartic interaction, it is possible to find the exact solutions of the scalar equation on this background. These modes turn out to be invariant under the SU(4) subgroup of the SO(8) isometry group, whereas there are no corresponding SU(4) singlet Bogomol'nyi-Prasad-Sommerfeld operators of dimensions one or two on the boundary theory constructed by Aharony, Bergman, Jafferis, and Maldacena. Noticing the interchange of 8{sub s} and 8{sub c} representations under skew-whiffing in the bulk, we propose the theory of antimembranes should similarly be obtained from Aharony, Bergman, Jafferis, and Maldacena's theory by swapping these representations. In particular, this enables us to identify the dual boundary operators of the two scalar modes. We deform the boundary theory by the dual operators and examine the fermionic field equations, and compare the solutions of the deformed theory with those of the bulk.
Conformal field theories, representations and lattice constructions
NASA Astrophysics Data System (ADS)
Dolan, L.; Goddard, P.; Montague, P.
1996-07-01
An account is given of the structure and representations of chiral bosonic meromorphic conformal field theories (CFT's), and, in particular, the conditions under which such a CFT may be extended by a representation to form a new theory. This general approach is illustrated by considering the untwisted and Z 2-twisted theories, ℋ( Λ) andtilde H(Λ ) respectively, which may be constructed from a suitable even Euclidean lattice Λ. Similarly, one may construct latticesΛ _C andtilde Λ _C by analogous constructions from a doubly-even binary codeC. In the case whenC is self-dual, the corresponding lattices are also. Similarly, ℋ( Λ) andtilde H(Λ ) are self-dual if and only if Λ is. We show thatH(Λ _C ) has a natural “triality” structure, which induces an isomorphismH(tilde Λ _C ) ≡tilde H(Λ _C ) and also a triality structure ontilde H(tilde Λ _C ). ForC the Golay code,tilde Λ _C is the Leech lattice, and the triality ontilde H(tilde Λ _C ) is the symmetry which extends the natural action of (an extension of) Conway's group on this theory to the Monster, so setting triality and Frenkel, Lepowsky and Meurman's construction of the natural Monster module in a more general context. The results also serve to shed some light on the classification of self-dual CFT's. We find that of the 48 theories ℋ( Λ) andtilde H(Λ ) with central charge 24 that there are 39 distinct ones, and further that all 9 coincidences are accounted for by the isomorphism detailed above, induced by the existence of a doubly-even self-dual binary code.
Facial expression recognition with facial parts based sparse representation classifier
NASA Astrophysics Data System (ADS)
Zhi, Ruicong; Ruan, Qiuqi
2009-10-01
Facial expressions play important role in human communication. The understanding of facial expression is a basic requirement in the development of next generation human computer interaction systems. Researches show that the intrinsic facial features always hide in low dimensional facial subspaces. This paper presents facial parts based facial expression recognition system with sparse representation classifier. Sparse representation classifier exploits sparse representation to select face features and classify facial expressions. The sparse solution is obtained by solving l1 -norm minimization problem with constraint of linear combination equation. Experimental results show that sparse representation is efficient for facial expression recognition and sparse representation classifier obtain much higher recognition accuracies than other compared methods.
Knowledge representation techniques for seismic signal understanding
Not Available
1986-03-01
Seismic monitoring and discrimination of seismic events for purposes of nuclear test ban verification require the interpretation of large volumes of uncertain signal data by seismic experts. Several levels of knowledge representation are envisioned to make the transduction from raw signal data to the level of symbolic representation used to represent knowledge by AI techniques. At the lower level, techniques drawn from the feature based approach to speech recognition and syntactic pattern recognition address primitive features and segmentation into symbolic units of syntax which apply to various representations or transforms of the seismic signal, such as seismograms. At a higher level, conventional knowledge representation schemes and new algebraic approaches to knowledge representation based on algebraic systems are considered as they might apply to representations of the signal established by the lower level techniques. This report defines and outlines these techniques as well as describes how they are likely to be successfully integrated into a unified approach for representing knowledge in seismic signals for symbolic signal processing. The report also recommends further steps and directions the research should take and includes a preliminary bibliography covering both theoretical and applied aspects of the knowledge representation techniques discussed. (ACR)
Learning Sparse Representations of Depth
NASA Astrophysics Data System (ADS)
Tosic, Ivana; Olshausen, Bruno A.; Culpepper, Benjamin J.
2011-09-01
This paper introduces a new method for learning and inferring sparse representations of depth (disparity) maps. The proposed algorithm relaxes the usual assumption of the stationary noise model in sparse coding. This enables learning from data corrupted with spatially varying noise or uncertainty, typically obtained by laser range scanners or structured light depth cameras. Sparse representations are learned from the Middlebury database disparity maps and then exploited in a two-layer graphical model for inferring depth from stereo, by including a sparsity prior on the learned features. Since they capture higher-order dependencies in the depth structure, these priors can complement smoothness priors commonly used in depth inference based on Markov Random Field (MRF) models. Inference on the proposed graph is achieved using an alternating iterative optimization technique, where the first layer is solved using an existing MRF-based stereo matching algorithm, then held fixed as the second layer is solved using the proposed non-stationary sparse coding algorithm. This leads to a general method for improving solutions of state of the art MRF-based depth estimation algorithms. Our experimental results first show that depth inference using learned representations leads to state of the art denoising of depth maps obtained from laser range scanners and a time of flight camera. Furthermore, we show that adding sparse priors improves the results of two depth estimation methods: the classical graph cut algorithm by Boykov et al. and the more recent algorithm of Woodford et al.
Contacts de langues et representations (Language Contacts and Representations).
ERIC Educational Resources Information Center
Matthey, Marinette, Ed.
1997-01-01
Essays on language contact and the image of language, entirely in French, include: "Representations 'du' contexte et representations 'en' contexte? Eleves et enseignants face a l'apprentissage de la langue" ("Representations 'of' Context or Representations 'in' Context? Students and Teachers Facing Language Learning" (Laurent Gajo); "Le crepuscule…
Grassmannian sparse representations
NASA Astrophysics Data System (ADS)
Azary, Sherif; Savakis, Andreas
2015-05-01
We present Grassmannian sparse representations (GSR), a sparse representation Grassmann learning framework for efficient classification. Sparse representation classification offers a powerful approach for recognition in a variety of contexts. However, a major drawback of sparse representation methods is their computational performance and memory utilization for high-dimensional data. A Grassmann manifold is a space that promotes smooth surfaces where points represent subspaces and the relationship between points is defined by the mapping of an orthogonal matrix. Grassmann manifolds are well suited for computer vision problems because they promote high between-class discrimination and within-class clustering, while offering computational advantages by mapping each subspace onto a single point. The GSR framework combines Grassmannian kernels and sparse representations, including regularized least squares and least angle regression, to improve high accuracy recognition while overcoming the drawbacks of performance and dependencies on high dimensional data distributions. The effectiveness of GSR is demonstrated on computationally intensive multiview action sequences, three-dimensional action sequences, and face recognition datasets.
Spacecraft Attitude Representations
NASA Technical Reports Server (NTRS)
Markley, F. Landis
1999-01-01
The direction cosine matrix or attitude matrix is the most fundamental representation of the attitude, but it is very inefficient: It has six redundant parameters, it is difficult to enforce the six (orthogonality) constraints. the four-component quaternion representation is very convenient: it has only one redundant parameter, it is easy to enforce the normalization constraint, the attitude matrix is a homogeneous quadratic function of q, quaternion kinematics are bilinear in q and m. Euler angles are extensively used: they often have a physical interpretation, they provide a natural description of some spacecraft motions (COBE, MAP), but kinematics and attitude matrix involve trigonometric functions, "gimbal lock" for certain values of the angles. Other minimum (three-parameter) representations: Gibbs vector is infinite for 180 deg rotations, but useful for analysis, Modified Rodrigues Parameters are nonsingular, no trig functions, Rotation vector phi is nonsingular, but requires trig functions.
ERIC Educational Resources Information Center
Wei, Liew Tze; Sazilah, Salam
2012-01-01
This study investigated the effects of visual cues in multiple external representations (MER) environment on the learning performance of novices' program comprehension. Program codes and flowchart diagrams were used as dual representations in multimedia environment to deliver lessons on C-Programming. 17 field independent participants and 16 field…
Umbra's system representation.
McDonald, Michael James
2005-07-01
This document describes the Umbra System representation. Umbra System representation, initially developed in the spring of 2003, is implemented in Incr/Tcl using concepts borrowed from Carnegie Mellon University's Architecture Description Language (ADL) called Acme. In the spring of 2004 through January 2005, System was converted to Umbra 4, extended slightly, and adopted as the underlying software system for a variety of Umbra applications that support Complex Systems Engineering (CSE) and Complex Adaptive Systems Engineering (CASE). System is now a standard part Of Umbra 4. While Umbra 4 also includes an XML parser for System, the XML parser and Schema are not described in this document.
NASA Technical Reports Server (NTRS)
Walsh, Brian M.
2010-01-01
Dual wavelength lasers are discussed, covering fundamental aspects on the spectroscopy and laser dynamics of these systems. Results on Tm:Ho:Er:YAG dual wavelength laser action (Ho at 2.1 m and Er at 2.9 m) as well as Nd:YAG (1.06 and 1.3 m) are presented as examples of such dual wavelength systems. Dual wavelength lasers are not common, but there are criteria that govern their behavior. Based on experimental studies demonstrating simultaneous dual wavelength lasing, some general conclusions regarding the successful operation of multi-wavelength lasers can be made.
22 CFR 145.17 - Certifications and representations.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Certifications and representations. 145.17 Section 145.17 Foreign Relations DEPARTMENT OF STATE CIVIL RIGHTS GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 145.17 Certifications and representations....
Student Engagement: Stakeholder Perspectives on Course Representation in University Governance
ERIC Educational Resources Information Center
Carey, Philip
2013-01-01
Student engagement has become a key feature of UK higher education policy and analysis. At the core of this is a notion of engagement characterised by dialogue and joint venture. The article explores this by considering the role of student representation in university governance. It focuses on the system of course representation that is a feature…
SNARC Hunting: Examining Number Representation in Deaf Students
ERIC Educational Resources Information Center
Bull, R.; Marschark, M.; Blatto-Vallee, G.
2005-01-01
Many deaf children and adults show lags in mathematical abilities. The current study examines the basic number representations that allow individuals to perform higher-level arithmetical procedures. These representations are normally present in the earliest stages of development, but they may be affected by cultural, developmental, and educational…
ERIC Educational Resources Information Center
Tervo, Juuso
2012-01-01
In "Postphysical Vision: Art Education's Challenge in an Age of Globalized Aesthetics (AMondofesto)" (2008) and "Beyond Aesthetics: Returning Force and Truth to Art and Its Education" (2009), jan jagodzinski argued for politics that go "beyond" representation--a project that radically questions visual culture…
Reading Students' Representations
ERIC Educational Resources Information Center
Diezmann, Carmel M.; McCosker, Natalie T.
2011-01-01
Representations play a key role in mathematical thinking: They offer "a medium" to express mathematical knowledge or organize mathematical information and to discern mathematical relationships (e.g., relative household expenditures on a pie chart) using text, symbols, or graphics. They also furnish "tools" for mathematical processes (e.g., use of…
[Time perceptions and representations].
Tordjman, S
2015-09-01
Representations of time and time measurements depend on subjective constructs that vary according to changes in our concepts, beliefs, societal needs and technical advances. Similarly, the past, the future and the present are subjective representations that depend on each individual's psychic time and biological time. Therefore, there is no single, one-size-fits-all time for everyone, but rather a different, subjective time for each individual. We need to acknowledge the existence of different inter-individual times but also intra-individual times, to which different functions and different rhythms are attached, depending on the system of reference. However, the construction of these time perceptions and representations is influenced by objective factors (physiological, physical and cognitive) related to neuroscience which will be presented and discussed in this article. Thus, studying representation and perception of time lies at the crossroads between neuroscience, human sciences and philosophy. Furthermore, it is possible to identify several constants among the many and various representations of time and their corresponding measures, regardless of the system of time reference. These include the notion of movements repeated in a stable rhythmic pattern involving the recurrence of the same interval of time, which enables us to define units of time of equal and invariable duration. This rhythmicity is also found at a physiological level and contributes through circadian rhythms, in particular the melatonin rhythm, to the existence of a biological time. Alterations of temporality in mental disorders will be also discussed in this article illustrated by certain developmental disorders such as autism spectrum disorders. In particular, the hypothesis will be developed that children with autism would need to create discontinuity out of continuity through stereotyped behaviors and/or interests. This discontinuity repeated at regular intervals could have been
On representations for joint moments using a joint coordinate system.
O'Reilly, Oliver M; Sena, Mark P; Feeley, Brian T; Lotz, Jeffrey C
2013-11-01
In studies of the biomechanics of joints, the representation of moments using the joint coordinate system has been discussed by several authors. The primary purpose of this technical brief is to emphasize that there are two distinct, albeit related, representations for moment vectors using the joint coordinate system. These distinct representations are illuminated by exploring connections between the Euler and dual Euler bases, the "nonorthogonal projections" presented in a recent paper by Desroches et al. (2010, "Expression of Joint Moment in the Joint Coordinate System," ASME J. Biomech. Eng., 132(11), p. 11450) and seminal works by Grood and Suntay (Grood and Suntay, 1983, "A Joint Coordinate System for the Clinical Description of Three-Dimensional Motions: Application to the Knee," ASME J. Biomech. Eng., 105(2), pp. 136-144) and Fujie et al. (1996, "Forces and Moment in Six-DOF at the Human Knee Joint: Mathematical Description for Control," Journal of Biomechanics, 29(12), pp. 1577-1585) on the knee joint. It is also shown how the representation using the dual Euler basis leads to straightforward definition of joint stiffnesses. PMID:24008987
The Functions of Multiple Representations.
ERIC Educational Resources Information Center
Ainsworth, Shaaron
1999-01-01
Discusses multiple representations and multimedia learning environments; describes a functional taxonomy of MERs (multiple external representations); and considers how MERs are used to support cognitive processes in learning and problem solving with computers. (Contains 41 references.) (Author/LRW)
Standard model of knowledge representation
NASA Astrophysics Data System (ADS)
Yin, Wensheng
2016-03-01
Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representation model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.
Poetic Re-Presentations on Trust in Higher Education
ERIC Educational Resources Information Center
West, Kim; Bloomquist, Candace
2015-01-01
This article discusses using poetic transcription (Glesne, 1997) as a tool for examining trust, including what trust looks and feels like from the "lived experiences" (Richardson, 1992) of university educators. We first explore the rationale for using poetic transcription in this study, discussing how and why poetry may be used as a…
Student Representation and Multiparty Politics in African Higher Education
ERIC Educational Resources Information Center
Luescher-Mamashela, Thierry M.; Mugume, Taabo
2014-01-01
The transition from one-party rule and other forms of authoritarianism to multiparty democracy in the 1990s has had a profound impact on the organisation and role of student politics in Africa. Against the background of student involvement in African politics in the twentieth century, leading up to student participation in Africa's…
In defense of abstract conceptual representations.
Binder, Jeffrey R
2016-08-01
An extensive program of research in the past 2 decades has focused on the role of modal sensory, motor, and affective brain systems in storing and retrieving concept knowledge. This focus has led in some circles to an underestimation of the need for more abstract, supramodal conceptual representations in semantic cognition. Evidence for supramodal processing comes from neuroimaging work documenting a large, well-defined cortical network that responds to meaningful stimuli regardless of modal content. The nodes in this network correspond to high-level "convergence zones" that receive broadly crossmodal input and presumably process crossmodal conjunctions. It is proposed that highly conjunctive representations are needed for several critical functions, including capturing conceptual similarity structure, enabling thematic associative relationships independent of conceptual similarity, and providing efficient "chunking" of concept representations for a range of higher order tasks that require concepts to be configured as situations. These hypothesized functions account for a wide range of neuroimaging results showing modulation of the supramodal convergence zone network by associative strength, lexicality, familiarity, imageability, frequency, and semantic compositionality. The evidence supports a hierarchical model of knowledge representation in which modal systems provide a mechanism for concept acquisition and serve to ground individual concepts in external reality, whereas broadly conjunctive, supramodal representations play an equally important role in concept association and situation knowledge. PMID:27294428
A-Optimal Projection for Image Representation.
He, Xiaofei; Zhang, Chiyuan; Zhang, Lijun; Li, Xuelong
2016-05-01
We consider the problem of image representation from the perspective of statistical design. Recent studies have shown that images are possibly sampled from a low dimensional manifold despite of the fact that the ambient space is usually very high dimensional. Learning low dimensional image representations is crucial for many image processing tasks such as recognition and retrieval. Most of the existing approaches for learning low dimensional representations, such as principal component analysis (PCA) and locality preserving projections (LPP), aim at discovering the geometrical or discriminant structures in the data. In this paper, we take a different perspective from statistical experimental design, and propose a novel dimensionality reduction algorithm called A-Optimal Projection (AOP). AOP is based on a linear regression model. Specifically, AOP finds the optimal basis functions so that the expected prediction error of the regression model can be minimized if the new representations are used for training the model. Experimental results suggest that the proposed approach provides a better representation and achieves higher accuracy in image retrieval. PMID:26353361
Nonlinear control for dual quaternion systems
NASA Astrophysics Data System (ADS)
Price, William D.
The motion of rigid bodies includes three degrees of freedom (DOF) for rotation, generally referred to as roll, pitch and yaw, and 3 DOF for translation, generally described as motion along the x, y and z axis, for a total of 6 DOF. Many complex mechanical systems exhibit this type of motion, with constraints, such as complex humanoid robotic systems, multiple ground vehicles, unmanned aerial vehicles (UAVs), multiple spacecraft vehicles, and even quantum mechanical systems. These motions historically have been analyzed independently, with separate control algorithms being developed for rotation and translation. The goal of this research is to study the full 6 DOF of rigid body motion together, developing control algorithms that will affect both rotation and translation simultaneously. This will prove especially beneficial in complex systems in the aerospace and robotics area where translational motion and rotational motion are highly coupled, such as when spacecraft have body fixed thrusters. A novel mathematical system known as dual quaternions provide an efficient method for mathematically modeling rigid body transformations, expressing both rotation and translation. Dual quaternions can be viewed as a representation of the special Euclidean group SE(3). An eight dimensional representation of screw theory (combining dual numbers with traditional quaternions), dual quaternions allow for the development of control techniques for 6 DOF motion simultaneously. In this work variable structure nonlinear control methods are developed for dual quaternion systems. These techniques include use of sliding mode control. In particular, sliding mode methods are developed for use in dual quaternion systems with unknown control direction. This method, referred to as self-reconfigurable control, is based on the creation of multiple equilibrium surfaces for the system in the extended state space. Also in this work, the control problem for a class of driftless nonlinear systems is
Representation in incremental learning
NASA Technical Reports Server (NTRS)
1993-01-01
Work focused on two areas in machine learning: representation for inductive learning and how to apply concept learning techniques to learning state preferences, which can represent search control knowledge for problem solving. Specifically, in the first area the issues of the effect of representation on learning, on how learning formalisms are biased, and how concept learning can benefit from the use of a hybrid formalism are addressed. In the second area, the issues of developing an agent to learn search control knowledge from the relative values of states, of the source of that qualitative information, and of the ability to use both quantitative and qualitative information in order to develop an effective problem-solving policy are examined.
Naturalising Representational Content
Shea, Nicholas
2014-01-01
This paper sets out a view about the explanatory role of representational content and advocates one approach to naturalising content – to giving a naturalistic account of what makes an entity a representation and in virtue of what it has the content it does. It argues for pluralism about the metaphysics of content and suggests that a good strategy is to ask the content question with respect to a variety of predictively successful information processing models in experimental psychology and cognitive neuroscience; and hence that data from psychology and cognitive neuroscience should play a greater role in theorising about the nature of content. Finally, the contours of the view are illustrated by drawing out and defending a surprising consequence: that individuation of vehicles of content is partly externalist. PMID:24563661
Naturalising Representational Content.
Shea, Nicholas
2013-05-01
This paper sets out a view about the explanatory role of representational content and advocates one approach to naturalising content - to giving a naturalistic account of what makes an entity a representation and in virtue of what it has the content it does. It argues for pluralism about the metaphysics of content and suggests that a good strategy is to ask the content question with respect to a variety of predictively successful information processing models in experimental psychology and cognitive neuroscience; and hence that data from psychology and cognitive neuroscience should play a greater role in theorising about the nature of content. Finally, the contours of the view are illustrated by drawing out and defending a surprising consequence: that individuation of vehicles of content is partly externalist. PMID:24563661
SLE and Virasoro Representations: Fusion
NASA Astrophysics Data System (ADS)
Dubédat, Julien
2015-06-01
We continue the study of null-vector equations in relation with partition functions of (systems of) Schramm-Loewner Evolutions (SLEs) by considering the question of fusion. Starting from n commuting SLEs seeded at distinct points, the partition function satisfies n null-vector equations (at level 2). We show how to obtain higher level null-vector equations by coalescing the seeds one by one. As an example, we extend Schramm's formula (for the position of a marked bulk point relatively to a chordal SLE trace) to an arbitrary number of SLE strands. The argument combines input from representation theory—the study of Verma modules for the Virasoro algebra—with regularity estimates, themselves based on hypoellipticity and stochastic flow arguments.
Supramodal representation of emotions.
Klasen, Martin; Kenworthy, Charles A; Mathiak, Krystyna A; Kircher, Tilo T J; Mathiak, Klaus
2011-09-21
Supramodal representation of emotion and its neural substrates have recently attracted attention as a marker of social cognition. However, the question whether perceptual integration of facial and vocal emotions takes place in primary sensory areas, multimodal cortices, or in affective structures remains unanswered yet. Using novel computer-generated stimuli, we combined emotional faces and voices in congruent and incongruent ways and assessed functional brain data (fMRI) during an emotional classification task. Both congruent and incongruent audiovisual stimuli evoked larger responses in thalamus and superior temporal regions compared with unimodal conditions. Congruent emotions were characterized by activation in amygdala, insula, ventral posterior cingulate (vPCC), temporo-occipital, and auditory cortices; incongruent emotions activated a frontoparietal network and bilateral caudate nucleus, indicating a greater processing load in working memory and emotion-encoding areas. The vPCC alone exhibited differential reactions to congruency and incongruency for all emotion categories and can thus be considered a central structure for supramodal representation of complex emotional information. Moreover, the left amygdala reflected supramodal representation of happy stimuli. These findings document that emotional information does not merge at the perceptual audiovisual integration level in unimodal or multimodal areas, but in vPCC and amygdala. PMID:21940454
Spatial representation of soundscape
NASA Astrophysics Data System (ADS)
Boubezari, Mohammed; Bento Coelho, Jos-Luis
2001-05-01
For the last 30 years the concept of soundscape has been largely adopted in many scientific disciplines and by the urban experts for the benefit of a better comprehension and management of the sound environment. However, the spatial representation of the soundscape as a simple tool for the description, management or composition of sound environment is always needed. In this article a method is presented for the spatial sound representation with differentiated sources. The first results are shown. This method gives an account of the soundscape as close as possible to the way it can be perceived by the listener in each location. This method generates qualitative sound maps in a reduced urban scale, based on in situ measurements and on the implication of the measuring subject perception. The maps are sufficient enough to isolate many sound sources of the overall sound field. In this manner, sound quality refers to the sound attribute of a perceived object. It is neither an aesthetic judgment nor traditional psychoacoustics criteria. Concrete examples of application to squares in the city of Lisbon will be shown and discussed. The limits and the prospects of such a qualitative representation will also be presented and discussed.
Mental Representations of Weekdays
Ellis, David A.; Wiseman, Richard; Jenkins, Rob
2015-01-01
Keeping social appointments involves keeping track of what day it is. In practice, mismatches between apparent day and actual day are common. For example, a person might think the current day is Wednesday when in fact it is Thursday. Here we show that such mismatches are highly systematic, and can be traced to specific properties of their mental representations. In Study 1, mismatches between apparent day and actual day occurred more frequently on midweek days (Tuesday, Wednesday, and Thursday) than on other days, and were mainly due to intrusions from immediately neighboring days. In Study 2, reaction times to report the current day were fastest on Monday and Friday, and slowest midweek. In Study 3, participants generated fewer semantic associations for “Tuesday”, “Wednesday” and “Thursday” than for other weekday names. Similarly, Google searches found fewer occurrences of midweek days in webpages and books. Analysis of affective norms revealed that participants’ associations were strongly negative for Monday, strongly positive for Friday, and graded over the intervening days. Midweek days are confusable because their mental representations are sparse and similar. Mondays and Fridays are less confusable because their mental representations are rich and distinctive, forming two extremes along a continuum of change. PMID:26288194
Translation between representation languages
NASA Technical Reports Server (NTRS)
Vanbaalen, Jeffrey
1994-01-01
A capability for translating between representation languages is critical for effective knowledge base reuse. A translation technology for knowledge representation languages based on the use of an interlingua for communicating knowledge is described. The interlingua-based translation process consists of three major steps: translation from the source language into a subset of the interlingua, translation between subsets of the interlingua, and translation from a subset of the interlingua into the target language. The first translation step into the interlingua can typically be specified in the form of a grammar that describes how each top-level form in the source language translates into the interlingua. In cases where the source language does not have a declarative semantics, such a grammar is also a specification of a declarative semantics for the language. A methodology for building translators that is currently under development is described. A 'translator shell' based on this methodology is also under development. The shell has been used to build translators for multiple representation languages and those translators have successfully translated nontrivial knowledge bases.
Technology Transfer Automated Retrieval System (TEKTRAN)
Teton Russet is an early-maturing, medium- russeted, potato cultivar with high merit for both fresh-pack and processing. In early harvest trials in the Pacific Northwest, Teton Russet had total yields similar to Russet Norkotah, and higher than Ranger Russet and Russet Burbank. Marketable yield of T...
Tilt representation beyond the retinotopic level.
Parwaga, Sandeep; Buckley, David; Duke, Philip A
2016-01-01
We perceive a stable visual world, which enables successful interaction with our environment, despite movements of the eyes, head, and body. How are such perceptions formed? One possibility is that retino-centric visual input is transformed into representations at higher levels, such as head-, body-, or world-centered representations. We investigated this hypothesis using the tilt aftereffect in a balanced adaptation paradigm designed to isolate head-, body-, and world-centered aftereffects. Observers adapted to two oppositely tilted stimuli, each contingent on one of two different gaze, head, or body directions. We found aftereffects contingent on gaze direction, but not head or body direction. This demonstrates that adaptable tilt representations exist in a head-centric frame but not in higher reference frames. These aftereffects may be attributed to adaptation of retinotopic tilt-sensitive neurons whose responses are modulated by gaze direction (gain fields). Such neurons could support functionally head-centric tilt representations and are found as early as V1. On the basis of our results we would not expect activity in tilt-sensitive neurons to be modulated by head or body direction. The balanced adaptation paradigm is a useful tool for examining properties of the process responsible for gaze modulation of activity in visual neurons. PMID:26868889
Back in the USSR: Path Dependence Effects in Student Representation in Russia
ERIC Educational Resources Information Center
Chirikov, Igor; Gruzdev, Ivan
2014-01-01
This paper analyses the current state of student representation in Russia as deeply rooted in the institutional structure of the Soviet higher education system. The study traces the origins of existing institutional arrangements for student representation at the level of university governance and analyses how representation practices have been…
ERIC Educational Resources Information Center
McKitric, Eloise J.
The impact of economic conditions on two-earner families was examined. Three family types were studied: (1) dual-career family--both the husband and wife are in the labor force but in occupations classified as professional-technical or managerial; (2) dual-earner--both the husband and wife are in the labor force; and (3) traditional family--the…
ERIC Educational Resources Information Center
Gurtin, Lee
1980-01-01
The dual career couple is forced to make a series of choices and compromises that impact the realms of marriage and career. The dilemmas that confront dual career marriages can be overcome only by compromise, accommodation, and mutual understanding on the part of the individuals involved. A revamping of human resources and recruitment programs is…
NASA Technical Reports Server (NTRS)
Packard, D. T.
1982-01-01
A new class of electromechanical actuators is described. These dual drive actuators were developed for the NASA-JPL Galileo Spacecraft. The dual drive actuators are fully redundant and therefore have high inherent reliability. They can be used for a variety of tasks, and they can be fabricated quickly and economically.
The string tension of SU(3) representations
NASA Astrophysics Data System (ADS)
Deldar, Sedigheh
In this thesis, I study the theory of confinement by measuring the potentials and in particular the string tension, between static sources in a background of gluons in pure gauge SU(3). The potentials between static sources in a variety of representations (fundamental, 8, 6, 15-antisymmetric, 10, 27 and 15- symmetric) have been computed by measuring Wilson loops. Wilson loops for higher representations have been measured in terms of Wilson loops of the fundamental representation. The string tensions have been computed from fitting the potentials to a Coloumbic plus a linear term. The simulations have been done primarily on anisotropic lattices, using a O(a2) tadpole improved action. A range of lattice spacings (0.43 fm, 0.25 fm and 0.11 fm) and volumes (83 × 24, 103 × 24, 163 × 24 and 183 × 24) has been used to extrapolate to the continuum and to control finite volume effects. In addition, a simulation at a single lattice spacing has been performed on an isotropic (84) lattice. The potentials between static sources in various representations in SU(3) have also been calculated based on the fat-center-vortices model. At intermediate distances, the results from both the numerical and model calculations are in qualitative agreement with ``Casimir scaling,'' which says that the string tension is proportional to the quadratic operator of the representation. For large distances (as large as 2.4 fm) no color screening or change of the potential slope has been observed from the lattice calculations of this work. However, from the fat-center- vortices model, screening and change of the potential slope is seen for zero triality and non-zero triality representations, respectively.
Women in Higher Education Management.
ERIC Educational Resources Information Center
Commonwealth Secretariat, London (England).
This volume contains 11 papers on the under-representation of women in higher education management in Bahrain, Finland, France, India, Indonesia, Malaysia, Nigeria, Peru, the United States and Canada, the South Pacific and the West Indies. All papers were written by women vice-chancellors, presidents and senior managers of universities in those…
Dual Credit/Dual Enrollment and Data Driven Policy Implementation
ERIC Educational Resources Information Center
Lichtenberger, Eric; Witt, M. Allison; Blankenberger, Bob; Franklin, Doug
2014-01-01
The use of dual credit has been expanding rapidly. Dual credit is a college course taken by a high school student for which both college and high school credit is given. Previous studies provided limited quantitative evidence that dual credit/dual enrollment is directly connected to positive student outcomes. In this study, predictive statistics…
Holographic Wilson loops in symmetric representations in {N} = {2}^{ast } super-Yang-Mills theory
NASA Astrophysics Data System (ADS)
Chen-Lin, Xinyi; Dekel, Amit; Zarembo, Konstantin
2016-02-01
We construct the D3-brane solution in the holographic dual of the {N} = {2}^{ast } theory that describes Wilson lines in symmetric representations of the gauge group. The results perfectly agree with the direct field-theory predictions based on localization.
Unilateral Vestibular Loss Impairs External Space Representation
Borel, Liliane; Redon-Zouiteni, Christine; Cauvin, Pierre; Dumitrescu, Michel; Devèze, Arnaud; Magnan, Jacques; Péruch, Patrick
2014-01-01
The vestibular system is responsible for a wide range of postural and oculomotor functions and maintains an internal, updated representation of the position and movement of the head in space. In this study, we assessed whether unilateral vestibular loss affects external space representation. Patients with Menière's disease and healthy participants were instructed to point to memorized targets in near (peripersonal) and far (extrapersonal) spaces in the absence or presence of a visual background. These individuals were also required to estimate their body pointing direction. Menière's disease patients were tested before unilateral vestibular neurotomy and during the recovery period (one week and one month after the operation), and healthy participants were tested at similar times. Unilateral vestibular loss impaired the representation of both the external space and the body pointing direction: in the dark, the configuration of perceived targets was shifted toward the lesioned side and compressed toward the contralesioned hemifield, with higher pointing error in the near space. Performance varied according to the time elapsed after neurotomy: deficits were stronger during the early stages, while gradual compensation occurred subsequently. These findings provide the first demonstration of the critical role of vestibular signals in the representation of external space and of body pointing direction in the early stages after unilateral vestibular loss. PMID:24523916
Internal representation of two-dimensional shape.
Makioka, S; Inui, T; Yamashita, H
1996-01-01
The psychological space of shapes has been studied in many experiments. However, how shapes are represented in the brain has not been a major issue in psychological literature. Here, the characteristics of internal representation and how it was formed have been considered and an attempt has been made to explain the results of experiments in a unified manner. First, the data of similarity of alphabetic characters and random-dot patterns were reexamined. Multivariate analysis suggested that those patterns were represented by the combination of global features. Second, three-layer neural networks were trained to perform categorization or identity transformation of the same sets of patterns as used in psychological experiments, and activation patterns of the hidden units were analyzed. When the network learned categorization of the patterns, its internal representation was not similar to the representation suggested by psychological experiments. But a network which learned identity transformation of the patterns could acquire such an internal representation. The transformation performed by this kind of network is similar to principal-component analysis in that it projects the input image onto a lower-dimensional space. From these results it is proposed that two-dimensional shapes are represented in human brain by a process like principal-component analysis. This idea is compatible with the findings in neurophysiological studies about higher visual areas. PMID:8938008
Reference duality and representation duality in information geometry
NASA Astrophysics Data System (ADS)
Zhang, Jun
2015-01-01
Classical information geometry prescribes, on the parametric family of probability functions Mθ: (i) a Riemannian metric given by the Fisher information; (ii) a pair of dual connections (giving rise to the family of α-connections) that preserve the metric under parallel transport by their joint actions; and (iii) a family of (non-symmetric) divergence functions (α-divergence) defined on Mθ × Mθ, which induce the metric and the dual connections. The role of α parameter, as used in α-connection and in α-embedding, is not commonly differentiated. For instance, the case with α = ±1 may refer either to dually-flat (e- or m-) connections or to exponential and mixture families of density functions. Here we illuminate that there are two distinct types of duality in information geometry, one concerning the referential status of a point (probability function, normalized or denormalized) expressed in the divergence function ("reference duality") and the other concerning the representation of probability functions under an arbitrary monotone scaling ("representation duality"). They correspond to, respectively, using α as a mixture parameter for constructing divergence functions or as a power exponent parameter for monotone embedding of probability functions. These two dualities are coupled into referential-representational biduality for manifolds of denormalized probability functions with α-Hessian structure (i.e, transitively flat α-geometry) and for manifolds induced from homogeneous divergence functions with (α,β)-parameters but one-parameter family of (α ṡ β)-connections.
NASA Astrophysics Data System (ADS)
Chang, Chi-Ming
This dissertation splits into two distinct halves. The first half is devoted to the study of the holography of higher spin gauge theory in AdS 3. We present a conjecture that the holographic dual of W N minimal model in a 't Hooft-like large N limit is an unusual "semi-local" higher spin gauge theory on AdS3 x 1. At each point on the S1 lives a copy of three-dimensional Vasiliev theory, that contains an infinite tower of higher spin gauge fields coupled to a single massive complex scalar propagating in AdS3. The Vasiliev theories at different points on the S1 are correlated only through the AdS3 boundary conditions on the massive scalars. All but one single tower of higher spin symmetries are broken by the boundary conditions. This conjecture is checked by comparing tree-level two- and three-point functions, and also one-loop partition functions on both side of the duality. The second half focuses on the holography of higher spin gauge theory in AdS 4. We demonstrate that a supersymmetric and parity violating version of Vasiliev's higher spin gauge theory in AdS4 admits boundary conditions that preserve N = 0,1,2,3,4 or 6 supersymmetries. In particular, we argue that the Vasiliev theory with U( M) Chan-Paton and N = 6 boundary condition is holographically dual to the 2+1 dimensional U(N) k x U(M) -k ABJ theory in the limit of large N, k and finite M. In this system all bulk higher spin fields transform in the adjoint of the U(M) gauge group, whose bulk t'Hooft coupling is M/N. Our picture suggests that the supersymmetric Vasiliev theory can be obtained as a limit of type IIA string theory in AdS4 x CP3, and that the non-Abelian Vasiliev theory at strong bulk 't Hooft coupling smoothly turn into a string field theory. The fundamental string is a singlet bound state of Vasiliev's higher spin particles held together by U(M) gauge interactions.
Geographic representation in spatial analysis
NASA Astrophysics Data System (ADS)
Miller, Harvey J.
Spatial analysis mostly developed in an era when data was scarce and computational power was expensive. Consequently, traditional spatial analysis greatly simplifies its representations of geography. The rise of geographic information science (GISci) and the changing nature of scientific questions at the end of the 20th century suggest a comprehensive re-examination of geographic representation in spatial analysis. This paper reviews the potential for improved representations of geography in spatial analysis. Existing tools in spatial analysis and new tools available from GISci have tremendous potential for bringing more sophisticated representations of geography to the forefront of spatial analysis theory and application.
Resource representation in COMPASS
NASA Technical Reports Server (NTRS)
Fox, Barry R.
1991-01-01
A set of viewgraphs on resource representation in COMPASS is given. COMPASS is an incremental, interactive, non-chronological scheduler written in Ada with an X-windows user interface. Beginning with an empty schedule, activities are added to the schedule one at a time, taking into consideration the placement of the activities already on the timeline and the resources that have been reserved for them. The order that the activities are added to the timeline and their location on the timeline are controlled by selection and placement commands invoked by the user. The order that activities are added to the timeline and their location are independent. The COMPASS code library is a cost effective platform for the development of new scheduling applications. It can be effectively used off the shelf for compatible scheduling applications or it can be used as a parts library for the development of custom scheduling systems.
Parental representations of transsexuals.
Parker, G; Barr, R
1982-06-01
The parental representations of 30 male-to-female transsexuals were rated using a measure of fundamental parental dimensions and shown to be of acceptable validity as a measure both of perceived and actual parental characteristics. Scores on that measure were compared separately against scores returned by matched male and female controls. The transsexuals did not differ from the male controls in their scoring of their mothers but did score their fathers as less caring and more overprotective. These differences were weaker for the comparisons made against the female controls. Item analyses suggested that the greater paternal "overprotection" experienced by transsexuals was due to their fathers being perceived as offering less encouragement to their sons' independence and autonomy. Several interpretations of the findings are considered. PMID:7138296
Intentionality, Representation, and Anticipation
NASA Astrophysics Data System (ADS)
De Preester, Helena
2002-09-01
Both Brentano and Merleau-Ponty have developed an account of intentionality, which nevertheless differ profoundly in the following respect. According to Brentano, intentionality mainly is a matter of mental presentations. This marks the beginning of phenomenology's difficult relation with the nature of the intentional reference. Merleau-Ponty, on the other hand, has situated intentionality on the level of the body, a turn which has important implications for the nature of intentionality. Intentionality no longer is primarily based on having (re)presentations, but is rooted in the dynamics of the living body. To contrast those approaches enables us to make clear in what way intentionality is studied nowadays. On the one hand, intentionality is conceived of as a matter of formal-syntactical causality in cognitive science, and in particular in classical-computational theory. On the other hand, a interactivist approach offers a more Merleau-Ponty-like point of view, in which autonomy, embodiment and interaction are stressed.
Age Differences in Symbolic Representation: Fluidity in Representational Construction.
ERIC Educational Resources Information Center
Reifel, Stuart
This paper reports a cross-sectional, developmental study of the fluidity of children's mental functioning (representational skills) in contexts involving the representational use of blocks. Data were collected from a sample of 40 children from a laboratory school: 20 four-year-olds and 20 seven-year-olds, with an equal number of boys and girls in…
Cervigram image segmentation based on reconstructive sparse representations
NASA Astrophysics Data System (ADS)
Zhang, Shaoting; Huang, Junzhou; Wang, Wei; Huang, Xiaolei; Metaxas, Dimitris
2010-03-01
We proposed an approach based on reconstructive sparse representations to segment tissues in optical images of the uterine cervix. Because of large variations in image appearance caused by the changing of the illumination and specular reflection, the color and texture features in optical images often overlap with each other and are not linearly separable. By leveraging sparse representations the data can be transformed to higher dimensions with sparse constraints and become more separated. K-SVD algorithm is employed to find sparse representations and corresponding dictionaries. The data can be reconstructed from its sparse representations and positive and/or negative dictionaries. Classification can be achieved based on comparing the reconstructive errors. In the experiments we applied our method to automatically segment the biomarker AcetoWhite (AW) regions in an archive of 60,000 images of the uterine cervix. Compared with other general methods, our approach showed lower space and time complexity and higher sensitivity.
Holography, unfolding and higher spin theory
NASA Astrophysics Data System (ADS)
Vasiliev, M. A.
2013-05-01
Holographic duality is argued to relate classes of models that have equivalent unfolded formulation, hence exhibiting different space-time visualizations for the same theory. This general phenomenon is illustrated by the AdS4 higher spin gauge theory shown to be dual to the theory of 3d conformal currents of all spins interacting with 3d conformal higher spin fields of Chern-Simons type. Generally, the resulting 3d boundary conformal theory is nonlinear, providing an interacting version of the 3d boundary sigma model conjectured by Klebanov and Polyakov to be dual to the AdS4 higher spin theory in the large N limit. Being a gauge theory, it escapes the conditions of the theorem of Maldacena and Zhiboedov, which force a 3d boundary conformal theory to be free. Two reductions of particular higher spin gauge theories where boundary higher spin gauge fields decouple from the currents and which have free-boundary duals are identified. Higher spin holographic duality is also discussed for the cases of AdS3/CFT2 and duality between higher spin theories and nonrelativistic quantum mechanics. In the latter case, it is shown in particular that (dS) AdS geometry in the higher spin setup is dual to the (inverted) harmonic potential in the quantum-mechanical setup. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’.
The tri-Hamiltonian dual system of supersymmetric two boson system
NASA Astrophysics Data System (ADS)
Zhang, Mengxia; Tian, Kai; Zhang, Lei
2016-09-01
The dual system of the supersymmetric two boson system is constructed through the approach of tri-Hamiltonian duality, and inferred from this duality, its zero-curvature representation is also figured out. Furthermore, the dual system is shown to be equivalent to a N = 2 supersymmetric Camassa-Holm equation, and this relation results in a new linear spectral problem for the N = 2 supersymmetric Camassa-Holm equation.
Knowledge Representation: A Brief Review.
ERIC Educational Resources Information Center
Vickery, B. C.
1986-01-01
Reviews different structures and techniques of knowledge representation: structure of database records and files, data structures in computer programming, syntatic and semantic structure of natural language, knowledge representation in artificial intelligence, and models of human memory. A prototype expert system that makes use of some of these…
A Philosophical Discussion of Representation.
ERIC Educational Resources Information Center
Moriarty, Sandra E.; Kenney, Keith
One of the most basic theoretical areas in the study of visual communication and visual literacy is the nature of representation. Some of the important research in this area is reviewed in this paper, and a model of representation is developed that satisfies many of the philosophical concerns. The paper begins with a discussion on the relationship…
Symbolic Representation of Probabilistic Worlds
ERIC Educational Resources Information Center
Feldman, Jacob
2012-01-01
Symbolic representation of environmental variables is a ubiquitous and often debated component of cognitive science. Yet notwithstanding centuries of philosophical discussion, the efficacy, scope, and validity of such representation has rarely been given direct consideration from a mathematical point of view. This paper introduces a quantitative…
The Representational Value of Hats
ERIC Educational Resources Information Center
Watson, Jane M.; Fitzallen, Noleine E.; Wilson, Karen G.; Creed, Julie F.
2008-01-01
The literature that is available on the topic of representations in mathematics is vast. One commonly discussed item is graphical representations. From the history of mathematics to modern uses of technology, a variety of graphical forms are available for middle school students to use to represent mathematical ideas. The ideas range from algebraic…
Polyakov loop of antisymmetric representations as a quantum impurity model
Mueck, Wolfgang
2011-03-15
The Polyakov loop of an operator in the antisymmetric representation in N=4 supersymmetric Yang-Mills theory on spacial R{sup 3} is calculated, to leading order in 1/N and at large 't Hooft coupling, by solving the saddle point equations of the corresponding quantum impurity model. Agreement is found with previous results from the supergravity dual, which is given by a D5-brane in an asymptotically AdS{sub 5}xS{sup 5} black brane background. It is shown that the azimuth angle, at which the dual D5-brane wraps the S{sup 5}, is related to the spectral asymmetry angle in the spectral density associated with the Green's function of the impurity fermions. Much of the calculation also applies to the Polyakov loop on spacial S{sup 3} or H{sup 3}.
UNDERSTANDING DUAL ACTIVE GALACTIC NUCLEUS ACTIVATION IN THE NEARBY UNIVERSE
Koss, Michael; Mushotzky, Richard; Veilleux, Sylvain; Vasudevan, Ranjan; Trippe, Margaret; Treister, Ezequiel
2012-02-20
We study the fraction of dual active galactic nuclei (AGNs) in a sample of 167 nearby (z < 0.05), moderate-luminosity, ultra-hard X-ray-selected AGNs from the all-sky Swift Burst Alert Telescope (BAT) survey. Combining new Chandra and Gemini observations together with optical and X-ray observations, we find that the dual AGN frequency at scales <100 kpc is {approx}10% (16/167). Of the 16 dual AGNs, only 3 (19%) were detected using X-ray spectroscopy and were not detected using emission line diagnostics. Close dual AGNs (<30 kpc) tend to be more common among the most X-ray luminous systems. In dual AGNs, the X-ray luminosity of both AGNs increases strongly with decreasing galaxy separation, suggesting that the merging event is key in powering both AGNs. Fifty percent of the AGNs with a very close companion (<15 kpc) are dual AGNs. We also find that dual AGNs are more likely to occur in major mergers and tend to avoid absorption line galaxies with elliptical morphologies. Finally, we find that SDSS Seyferts are much less likely than BAT AGNs (0.25% versus 7.8%) to be found in dual AGNs at scales <30 kpc because of a smaller number of companion galaxies, fiber collision limits, a tendency for AGNs at small separations to be detected only in X-rays, and a higher fraction of dual AGN companions with increasing AGN luminosity.
Revealing children's implicit spelling representations.
Critten, Sarah; Pine, Karen J; Messer, David J
2013-06-01
Conceptualizing the underlying representations and cognitive mechanisms of children's spelling development is a key challenge for literacy researchers. Using the Representational Redescription model (Karmiloff-Smith), Critten, Pine and Steffler (2007) demonstrated that the acquisition of phonological and morphological knowledge may be underpinned by increasingly explicit levels of spelling representation. However, their proposal that implicit representations may underlie early 'visually based' spelling remains unresolved. Children (N = 101, aged 4-6 years) were given a recognition task (Critten et al., 2007) and a novel production task, both involving verbal justifications of why spellings are correct/incorrect, strategy use and word pattern similarity. Results for both tasks supported an implicit level of spelling characterized by the ability to correctly recognize/produce words but the inability to explain operational strategies or generalize knowledge. Explicit levels and multiple representations were also in evidence across the two tasks. Implications for cognitive mechanisms underlying spelling development are discussed. PMID:23659891
A generalized wavelet extrema representation
Lu, Jian; Lades, M.
1995-10-01
The wavelet extrema representation originated by Stephane Mallat is a unique framework for low-level and intermediate-level (feature) processing. In this paper, we present a new form of wavelet extrema representation generalizing Mallat`s original work. The generalized wavelet extrema representation is a feature-based multiscale representation. For a particular choice of wavelet, our scheme can be interpreted as representing a signal or image by its edges, and peaks and valleys at multiple scales. Such a representation is shown to be stable -- the original signal or image can be reconstructed with very good quality. It is further shown that a signal or image can be modeled as piecewise monotonic, with all turning points between monotonic segments given by the wavelet extrema. A new projection operator is introduced to enforce piecewise inonotonicity of a signal in its reconstruction. This leads to an enhancement to previously developed algorithms in preventing artifacts in reconstructed signal.
M-idempotent and self-dual morphological filters.
Bouaynaya, Nidhal; Charif-Chefchaouni, Mohammed; Schonfeld, Dan
2012-04-01
In this paper, we present a comprehensive analysis of self-dual and m-idempotent operators. We refer to an operator as m-idempotent if it converges after m iterations. We focus on an important special case of the general theory of lattice morphology: spatially variant morphology, which captures the geometrical interpretation of spatially variant structuring elements. We demonstrate that every increasing self-dual morphological operator can be viewed as a morphological center. Necessary and sufficient conditions for the idempotence of morphological operators are characterized in terms of their kernel representation. We further extend our results to the representation of the kernel of m-idempotent morphological operators. We then rely on the conditions on the kernel representation derived and establish methods for the construction of m-idempotent and self-dual morphological operators. Finally, we illustrate the importance of the self-duality and m-idempotence properties by an application to speckle noise removal in radar images. PMID:22184254
Archival Representation in the Digital Age
ERIC Educational Resources Information Center
Zhang, Jane
2012-01-01
This study analyzes the representation systems of three digitized archival collections using the traditional archival representation framework of provenance, order, and content. The results of the study reveal a prominent role of provenance representation, a compromised role of order representation, and an active role of content representation in…
Jenkins, Rob; Burton, A. Mike
2011-01-01
Photographs are often used to establish the identity of an individual or to verify that they are who they claim to be. Yet, recent research shows that it is surprisingly difficult to match a photo to a face. Neither humans nor machines can perform this task reliably. Although human perceivers are good at matching familiar faces, performance with unfamiliar faces is strikingly poor. The situation is no better for automatic face recognition systems. In practical settings, automatic systems have been consistently disappointing. In this review, we suggest that failure to distinguish between familiar and unfamiliar face processing has led to unrealistic expectations about face identification in applied settings. We also argue that a photograph is not necessarily a reliable indicator of facial appearance, and develop our proposal that summary statistics can provide more stable face representations. In particular, we show that image averaging stabilizes facial appearance by diluting aspects of the image that vary between snapshots of the same person. We review evidence that the resulting images can outperform photographs in both behavioural experiments and computer simulations, and outline promising directions for future research. PMID:21536553
Dual adaptive control: Design principles and applications
NASA Technical Reports Server (NTRS)
Mookerjee, Purusottam
1988-01-01
The design of an actively adaptive dual controller based on an approximation of the stochastic dynamic programming equation for a multi-step horizon is presented. A dual controller that can enhance identification of the system while controlling it at the same time is derived for multi-dimensional problems. This dual controller uses sensitivity functions of the expected future cost with respect to the parameter uncertainties. A passively adaptive cautious controller and the actively adaptive dual controller are examined. In many instances, the cautious controller is seen to turn off while the latter avoids the turn-off of the control and the slow convergence of the parameter estimates, characteristic of the cautious controller. The algorithms have been applied to a multi-variable static model which represents a simplified linear version of the relationship between the vibration output and the higher harmonic control input for a helicopter. Monte Carlo comparisons based on parametric and nonparametric statistical analysis indicate the superiority of the dual controller over the baseline controller.
ERIC Educational Resources Information Center
Hendrickson, Robert M.; Gregory, Dennis E.
Decisions made by federal and state courts during 1983 concerning higher education are reported in this chapter. Issues of employment and the treatment of students underlay the bulk of the litigation. Specific topics addressed in these and other cases included federal authority to enforce regulations against age discrimination and to revoke an…
ERIC Educational Resources Information Center
Hendrickson, Robert M.
Litigation in 1987 was very brisk with an increase in the number of higher education cases reviewed. Cases discussed in this chapter are organized under four major topics: (1) intergovernmental relations; (2) employees, involving discrimination claims, tenured and nontenured faculty, collective bargaining and denial of employee benefits; (3)…
ERIC Educational Resources Information Center
Hendrickson, Robert M.; Finnegan, Dorothy E.
The higher education case law in 1988 is extensive. Cases discussed in this chapter are organized under five major topics: (1) intergovernmental relations; (2) employees, involving discrimination claims, tenured and nontenured faculty, collective bargaining, and denial of employee benefits; (3) students, involving admissions, financial aid, First…
ERIC Educational Resources Information Center
Hendrickson, Robert M.
This eighth chapter of "The Yearbook of School Law, 1986" summarizes and analyzes over 330 state and federal court cases litigated in 1985 in which institutions of higher education were involved. Among the topics examined were relationships between postsecondary institutions and various governmental agencies; discrimination in the employment of…
Computer aided surface representation
Barnhill, R.E.
1989-02-09
The central research problem of this project is the effective representation and display of surfaces, interpolating to given information, in three or more dimensions. In a typical problem, we wish to create a surface from some discrete information. If this information is itself on another surface, the problem is to determine a surface defined on a surface,'' which is discussed below. Often, properties of an already constructed surface are desired: such geometry processing'' is described below. The Summary of Proposed Research from our original proposal describes the aims of this research project. This Summary and the Table of Contents from the original proposal are enclosed as an Appendix to this Progress Report. The broad sweep from constructive mathematics through algorithms and computer graphics displays is utilized in the research. The wide range of activity, directed in both theory and applications, makes this project unique. Last month in the first Ardent Titan delivered in the State of Arizona came to our group, funded by the DOE and Arizona State University. Although the Titan is a commercial product, its newness requires our close collaboration with Ardent to maximize results. During the past year, four faculty members and several graduate research assistants have worked on this DOE project. The gaining of new professionals is an important aspect of this project. A listing of the students and their topics is given in the Appendix. The most significant publication during the past year is the book, Curves and Surfaces for Computer Aided Geometric Design, by Dr. Gerald Farin. This 300 page volume helps fill a considerable gap in the subject and includes many new results on Bernstein-Bezier curves and surfaces.
Representations of mechanical assembly sequences
NASA Astrophysics Data System (ADS)
Homem de Mello, Luiz S.; Sanderson, Arthur C.
1991-04-01
Five types of representations for assembly sequences are reviewed: the directed graph of feasible assembly sequences, the AND/OR graph of feasible assembly sequences, the set of establishment conditions, and two types of sets of precedence relationships. (precedence relationships between the establishment of one connection between parts and the establishment of another connection, and precedence relationships between the establishment of one connection and states of the assembly process). The mappings of one representation into the others are established. The correctness and completeness of these representations are established. The results presented are needed in the proof of correctness and completeness of algorithms for the generation of mechanical assembly sequences.
Attitude Representations for Kalman Filtering
NASA Technical Reports Server (NTRS)
Markley, F. Landis; Bauer, Frank H. (Technical Monitor)
2001-01-01
The four-component quaternion has the lowest dimensionality possible for a globally nonsingular attitude representation, it represents the attitude matrix as a homogeneous quadratic function, and its dynamic propagation equation is bilinear in the quaternion and the angular velocity. The quaternion is required to obey a unit norm constraint, though, so Kalman filters often employ a quaternion for the global attitude estimate and a three-component representation for small errors about the estimate. We consider these mixed attitude representations for both a first-order Extended Kalman filter and a second-order filter, as well for quaternion-norm-preserving attitude propagation.
Representations of mechanical assembly sequences
NASA Technical Reports Server (NTRS)
Homem De Mello, Luiz S.; Sanderson, Arthur C.
1991-01-01
Five types of representations for assembly sequences are reviewed: the directed graph of feasible assembly sequences, the AND/OR graph of feasible assembly sequences, the set of establishment conditions, and two types of sets of precedence relationships. (precedence relationships between the establishment of one connection between parts and the establishment of another connection, and precedence relationships between the establishment of one connection and states of the assembly process). The mappings of one representation into the others are established. The correctness and completeness of these representations are established. The results presented are needed in the proof of correctness and completeness of algorithms for the generation of mechanical assembly sequences.
NASA Astrophysics Data System (ADS)
Hasegawa, Bruce; Tang, H. Roger; Da Silva, Angela J.; Wong, Kenneth H.; Iwata, Koji; Wu, Max C.
2001-09-01
In comparison to conventional medical imaging techniques, dual-modality imaging offers the advantage of correlating anatomical information from X-ray computed tomography (CT) with functional measurements from single-photon emission computed tomography (SPECT) or with positron emission tomography (PET). The combined X-ray/radionuclide images from dual-modality imaging can help the clinician to differentiate disease from normal uptake of radiopharmaceuticals, and to improve diagnosis and staging of disease. In addition, phantom and animal studies have demonstrated that a priori structural information from CT can be used to improve quantification of tissue uptake and organ function by correcting the radionuclide data for errors due to photon attenuation, partial volume effects, scatter radiation, and other physical effects. Dual-modality imaging therefore is emerging as a method of improving the visual quality and the quantitative accuracy of radionuclide imaging for diagnosis of patients with cancer and heart disease.
The link between mental rotation ability and basic numerical representations
Thompson, Jacqueline M.; Nuerk, Hans-Christoph; Moeller, Korbinian; Cohen Kadosh, Roi
2013-01-01
Mental rotation and number representation have both been studied widely, but although mental rotation has been linked to higher-level mathematical skills, to date it has not been shown whether mental rotation ability is linked to the most basic mental representation and processing of numbers. To investigate the possible connection between mental rotation abilities and numerical representation, 43 participants completed four tasks: 1) a standard pen-and-paper mental rotation task; 2) a multi-digit number magnitude comparison task assessing the compatibility effect, which indicates separate processing of decade and unit digits; 3) a number-line mapping task, which measures precision of number magnitude representation; and 4) a random number generation task, which yields measures both of executive control and of spatial number representations. Results show that mental rotation ability correlated significantly with both size of the compatibility effect and with number mapping accuracy, but not with any measures from the random number generation task. Together, these results suggest that higher mental rotation abilities are linked to more developed number representation, and also provide further evidence for the connection between spatial and numerical abilities. PMID:23933002
Student Representation in Italy
ERIC Educational Resources Information Center
Foroni, Marzia
2011-01-01
The analysis begins with a comprehensive overview of legal provisions for student participation in higher education governance over the past few decades. How has the involvement of students in decision-making processes developed? The answer will be provided for the sub-institutional level of faculties and degree programmes; the institutional…
NASA Technical Reports Server (NTRS)
Trefny, Charles J (Inventor); Dippold, Vance F (Inventor)
2013-01-01
A new dual-mode ramjet combustor used for operation over a wide flight Mach number range is described. Subsonic combustion mode is usable to lower flight Mach numbers than current dual-mode scramjets. High speed mode is characterized by supersonic combustion in a free-jet that traverses the subsonic combustion chamber to a variable nozzle throat. Although a variable combustor exit aperture is required, the need for fuel staging to accommodate the combustion process is eliminated. Local heating from shock-boundary-layer interactions on combustor walls is also eliminated.
NASA Astrophysics Data System (ADS)
Weber, Joshua; Korver, Anna; Thrasher, Daniel; Walker, Thad
2016-05-01
We present progress towards a dual species nuclear magnetic oscillator using synchronous spin exchange optical pumping. By applying the bias field as a sequence of alkali 2 π pulses, we generate alkali polarization transverse to the bias field. The alkali polarization is then modulated at the noble gas resonance so that through spin exchange collisions the noble gas becomes polarized. This novel method of NMR suppresses the alkali field frequency shift by at least a factor of 2500 as compared to longitudinal NMR. We will present details of the apparatus and measurements of dual species co-magnetometry using this method. Research supported by the NSF and Northrop-Grumman Corp.
Dual Funding for Dual Enrollment: An Inducement or an Impediment?
ERIC Educational Resources Information Center
Hunt, Erika
2007-01-01
While the strategy of funding both systems provides an incentive for both school districts and community colleges to participate with dual enrollment, the current fiscal environment has drawn attention to the inefficient use of the dual funding structure. This article highlights the results of a case study on Florida's dual enrollment program…
Dynamic speech representations in the human temporal lobe
Leonard, Matthew K.; Chang, Edward F.
2014-01-01
Speech perception requires rapid integration of acoustic input with context-dependent knowledge. Recent methodological advances have allowed researchers to identify underlying information representations in primary and secondary auditory cortex, and to examine how context modulates these representations. We review recent studies that focus on contextual modulations of neural activity in the superior temporal gyrus (STG), a major hub for spectrotemporal encoding. Recent findings suggest a highly interactive flow of information processing through the auditory ventral stream, including influences of higher-level linguistic and metalinguistic knowledge. Such mechanisms may give rise to more abstract representations, such as those for words. We discuss the importance of characterizing neural representations of context-dependent and dynamic patterns of neural activity in the approach to speech perception research. PMID:24906217
Kernel weighted joint collaborative representation for hyperspectral image classification
NASA Astrophysics Data System (ADS)
Du, Qian; Li, Wei
2015-05-01
Collaborative representation classifier (CRC) has been applied to hyperspectral image classification, which intends to use all the atoms in a dictionary to represent a testing pixel for label assignment. However, some atoms that are very dissimilar to the testing pixel should not participate in the representation, or their contribution should be very little. The regularized version of CRC imposes strong penalty to prevent dissimilar atoms with having large representation coefficients. To utilize spatial information, the weighted sum of local spatial neighbors is considered as a joint spatial-spectral feature, which is actually for regularized CRC-based classification. This paper proposes its kernel version to further improve classification accuracy, which can be higher than those from the traditional support vector machine with composite kernel and the kernel version of sparse representation classifier.
Computer representation of molecular surfaces
Max, N.L.
1981-07-06
This review article surveys recent work on computer representation of molecular surfaces. Several different algorithms are discussed for producing vector or raster drawings of space-filling models formed as the union of spheres. Other smoother surfaces are also considered.
Vietnamese Document Representation and Classification
NASA Astrophysics Data System (ADS)
Nguyen, Giang-Son; Gao, Xiaoying; Andreae, Peter
Vietnamese is very different from English and little research has been done on Vietnamese document classification, or indeed, on any kind of Vietnamese language processing, and only a few small corpora are available for research. We created a large Vietnamese text corpus with about 18000 documents, and manually classified them based on different criteria such as topics and styles, giving several classification tasks of different difficulty levels. This paper introduces a new syllable-based document representation at the morphological level of the language for efficient classification. We tested the representation on our corpus with different classification tasks using six classification algorithms and two feature selection techniques. Our experiments show that the new representation is effective for Vietnamese categorization, and suggest that best performance can be achieved using syllable-pair document representation, an SVM with a polynomial kernel as the learning algorithm, and using Information gain and an external dictionary for feature selection.
Texture Representations Using Subspace Embeddings
Yang, Xiaodong; Tian, YingLi
2013-01-01
In this paper, we propose a texture representation framework to map local texture patches into a low-dimensional texture subspace. In natural texture images, textons are entangled with multiple factors, such as rotation, scaling, viewpoint variation, illumination change, and non-rigid surface deformation. Mapping local texture patches into a low-dimensional subspace can alleviate or eliminate these undesired variation factors resulting from both geometric and photometric transformations. We observe that texture representations based on subspace embeddings have strong resistance to image deformations, meanwhile, are more distinctive and more compact than traditional representations. We investigate both linear and non-linear embedding methods including Principle Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Locality Preserving Projections (LPP) to compute the essential texture subspace. The experiments in the context of texture classification on benchmark datasets demonstrate that the proposed subspace embedding representations achieve the state-of-the-art results while with much fewer feature dimensions. PMID:23710105
Texture Representations Using Subspace Embeddings.
Yang, Xiaodong; Tian, Yingli
2013-07-15
In this paper, we propose a texture representation framework to map local texture patches into a low-dimensional texture subspace. In natural texture images, textons are entangled with multiple factors, such as rotation, scaling, viewpoint variation, illumination change, and non-rigid surface deformation. Mapping local texture patches into a low-dimensional subspace can alleviate or eliminate these undesired variation factors resulting from both geometric and photometric transformations. We observe that texture representations based on subspace embeddings have strong resistance to image deformations, meanwhile, are more distinctive and more compact than traditional representations. We investigate both linear and non-linear embedding methods including Principle Component Analysis (PCA), Linear Discriminant Analysis (LDA), and Locality Preserving Projections (LPP) to compute the essential texture subspace. The experiments in the context of texture classification on benchmark datasets demonstrate that the proposed subspace embedding representations achieve the state-of-the-art results while with much fewer feature dimensions. PMID:23710105
Dictionary Learning Algorithms for Sparse Representation
Kreutz-Delgado, Kenneth; Murray, Joseph F.; Rao, Bhaskar D.; Engan, Kjersti; Lee, Te-Won; Sejnowski, Terrence J.
2010-01-01
Algorithms for data-driven learning of domain-specific overcomplete dictionaries are developed to obtain maximum likelihood and maximum a posteriori dictionary estimates based on the use of Bayesian models with concave/Schur-concave (CSC) negative log priors. Such priors are appropriate for obtaining sparse representations of environmental signals within an appropriately chosen (environmentally matched) dictionary. The elements of the dictionary can be interpreted as concepts, features, or words capable of succinct expression of events encountered in the environment (the source of the measured signals). This is a generalization of vector quantization in that one is interested in a description involving a few dictionary entries (the proverbial “25 words or less”), but not necessarily as succinct as one entry. To learn an environmentally adapted dictionary capable of concise expression of signals generated by the environment, we develop algorithms that iterate between a representative set of sparse representations found by variants of FOCUSS and an update of the dictionary using these sparse representations. Experiments were performed using synthetic data and natural images. For complete dictionaries, we demonstrate that our algorithms have improved performance over other independent component analysis (ICA) methods, measured in terms of signal-to-noise ratios of separated sources. In the overcomplete case, we show that the true underlying dictionary and sparse sources can be accurately recovered. In tests with natural images, learned overcomplete dictionaries are shown to have higher coding efficiency than complete dictionaries; that is, images encoded with an over-complete dictionary have both higher compression (fewer bits per pixel) and higher accuracy (lower mean square error). PMID:12590811
Ebbert, Jon O.; Morgan, Glen D.; Sherrill-Mittleman, Deborah; Asfar, Taghrid; Talcott, Wayne G.; DeBon, Margaret
2011-01-01
Introduction: Concomitant use of two forms of tobacco is an increasing public health concern, yet there is little consensus regarding a consistent definition of so-called “dual use.” We defined dual use as cigarette and smokeless tobacco (ST) consumption with either product used daily or nondaily. Methods: We analyzed a cohort of 36,013 Air Force recruits. We categorized dual tobacco use across 2 dimensions, type of tobacco products (cigarettes, ST, or others), and the frequency of use (daily vs. nondaily). We determined how varying the definition impacted the prevalence estimates and evaluated the prevalence estimate based on our recommended definition of dual use. Multivariate logistic regression analysis was used to evaluate the risk profile of dual users of ST and cigarettes versus mono users of ST and mono users of cigarettes. Results: Varying definitions of dual use vary prevalence estimates 50-fold (0.5%–25.3%). Including only ST and cigarettes narrows the prevalence estimate to less than 4-fold (2.0%–9.7%). Dual users are more likely to be young Caucasian males, with lower education, and from families with relatively higher incomes. Compared with mono users, dual users of cigarettes and ST have a distinct pattern of risk profiles. Conclusions: Depending on the definition of dual use, markedly different prevalence and risk profiles are observed. Dual users of ST and cigarettes are a unique group of tobacco users. We propose a common definition of dual use to advance our understanding of this unique group. PMID:21436298
Partial Data Traces: Efficient Generation and Representation
Mueller, F; De Supinski, B R; McKee, S A; Yoo, A
2001-08-20
Binary manipulation techniques are increasing in popularity. They support program transformations tailored toward certain program inputs, and these transformations have been shown to yield performance gains beyond the scope of static code optimizations without profile-directed feedback. They even deliver moderate gains in the presence of profile-guided optimizations. In addition, transformations can be performed on the entire executable, including library routines. This work focuses on program instrumentation, yet another application of binary manipulation. This paper reports preliminary results on generating partial data traces through dynamic binary rewriting. The contributions are threefold. First, a portable method for extracting precise data traces for partial executions of arbitrary applications is developed. Second, a set of hierarchical structures for compactly representing these accesses is developed. Third, an efficient online algorithm to detect regular accesses is introduced. The authors utilize dynamic binary rewriting to selectively collect partial address traces of regions within a program. This allows partial tracing of hot paths for only a short time during program execution in contrast to static rewriting techniques that lack hot path detection and also lack facilities to limit the duration of data collection. Preliminary results show reductions of three orders of a magnitude of inline instrumentation over a dual process approach involving context switching. They also report constant size representations for regular access patters in nested loops. These efforts are part of a larger project to counter the increasing gap between processor and main memory speeds by means of software optimization and hardware enhancements.
ERIC Educational Resources Information Center
Burton, John K.; Wildman, Terry M.
The purpose of this study was to test the applicability of the dual coding hypothesis to children's recall performance. The hypothesis predicts that visual interference will have a small effect on the recall of visually presented words or pictures, but that acoustic interference will cause a decline in recall of visually presented words and…
ERIC Educational Resources Information Center
Genesee, Fred
2008-01-01
Parents and child care personnel in English-dominant parts of the world often express misgivings about raising children bilingually. Their concerns are based on the belief that dual language learning during the infant-toddler stage confuses children, delays their development, and perhaps even results in reduced language competence. In this…
Dual Christoffel Transformations
NASA Astrophysics Data System (ADS)
Odake, S.; Sasaki, R.
2011-07-01
Crum's theorem and its modification à la Krein-Adler are formulated for the discrete quantum mechanics with real shifts, whose eigenfunctions consist of orthogonal polynomials of a discrete variable. The modification produces the associated polynomials with a finite number of degrees deleted. This in turn provides the well known Christoffel transformation for the dual orthogonal polynomials with the corresponding positions deleted.
A new dispenser cathode with dual-layer
NASA Astrophysics Data System (ADS)
Li, Yutao; Zhang, Honglai; Liu, Pukun; Zhang, Mingchen
2005-09-01
The emission and surface characteristics of the dispenser cathode coated with Os-W alloy and that coated with Os-W/Re are studied and compared. The dispenser cathode coated with Os-W/Re has been applied in electron gun measurement system for making measurement of higher emission current and life test. We called the cathode coated with Os-W/Re as the cathode with dual-layer. It is found that the dispenser cathode coated with dual-layer has higher current density than that coated only with Os-W alloy. After being activated, the cathode coated with dual-layer presents ternary composition on the surface of it. The W surface composition does not rise with time comparing with that of the cathode coated with Os-W alloy. In electron gun, the dispenser cathode coated with dual-layer has pulse current density of 30 A/cm 2 and life of more than 800 h.
Dual Coding Theory, Word Abstractness, and Emotion: A Critical Review of Kousta et al. (2011)
ERIC Educational Resources Information Center
Paivio, Allan
2013-01-01
Kousta, Vigliocco, Del Campo, Vinson, and Andrews (2011) questioned the adequacy of dual coding theory and the context availability model as explanations of representational and processing differences between concrete and abstract words. They proposed an alternative approach that focuses on the role of emotional content in the processing of…
Dual superconformal invariance, momentum twistors and Grassmannians
NASA Astrophysics Data System (ADS)
Mason, Lionel; Skinner, David
2009-11-01
Dual superconformal invariance has recently emerged as a hidden symmetry of planar scattering amplitudes in Script N = 4 super Yang-Mills theory. This symmetry can be made manifest by expressing amplitudes in terms of `momentum twistors', as opposed to the usual twistors that make the ordinary superconformal properties manifest. The relation between momentum twistors and on-shell momenta is algebraic, so the translation procedure does not rely on any choice of space-time signature. We show that tree amplitudes and box coefficients are succinctly generated by integration of holomorphic δ-functions in momentum twistors over cycles in a Grassmannian. This is analogous to, although distinct from, recent results obtained by Arkani-Hamed et al. in ordinary twistor space. We also make contact with Hodges' polyhedral representation of NMHV amplitudes in momentum twistor space.
World representations for unmanned vehicles
NASA Astrophysics Data System (ADS)
Broten, Gregory S.; Monckton, Simon P.; Mackay, David; Collier, Jack
2007-04-01
Unmanned vehicles (UxV) operate in numerous environments, with air, ground and marine representing the majority of the implementations. All unmanned vehicles, when traversing unknown space, have similar requirements. They must sense their environment, create a world representation, and, then plan a path that safely avoids obstacles and hazards. Traditionally, each unmanned vehicle class used environment specific assumptions to create a unique world representation that was tailored to it operating environment. Thus, an unmanned aerial vehicle (UAV) used the simplest possible world representation, where all space above the ground plane was free of obstacles. Conversely, an unmanned ground vehicle (UGV) required a world representation that was suitable to its complex and unstructured environment. Such a clear cut differentiation between UAV and UGV environments is no longer valid as UAVs have migrated down to elevations where terrestrial structures are located. Thus, the operating environment for a low flying UAV contains similarities to the environments experienced by UGVs. As a result, the world representation techniques and algorithms developed for UGVs are now applicable to UAVs, since low flying UAVs must sense and represent its world in order to avoid obstacles. Defence R&D Canada (DRDC) conducts research and development in both the UGV and UAV fields. Researchers have developed a platform neutral world representation, based upon a uniform 21/ II-D elevation grid, that is applicable to many UxV classes, including aerial and ground vehicles. This paper describes DRDC's generic world representation, known as the Global Terrain map, and provides an example of unmanned ground vehicle implementation, along with details of it applicability to aerial vehicles.
On representations of conformal field theories and the construction of orbifolds
NASA Astrophysics Data System (ADS)
Montague, P. S.
1996-09-01
We consider representations of meromorphic bosonic chiral conformal field theories and demonstrate that such a representation is completely specified by a state within the theory. The necessary and sufficient conditions upon this state are derived and, because of their form, we show that we may extend the representation to a representation of a suitable larger conformal field theory. In particular, we apply this procedure to the (untwisted) lattice conformal field theories (i.e. corresponding to the propagation of a bosonic string on a torus), and deduce that Dong's proof of the uniqueness of the twisted representation for the reflection-twisted projection of the Leech lattice conformal field theory generalises to an arbitrary even (self-dual) lattice. As a consequence, we see that the reflection-twisted lattice theories of Dolan, Goddard and Montague are truly self-dual, extending the analogies with the theories of lattices and codes which were being pursued. Some comments are also made on the general concept of the definition of an orbifold of a conformal field theory in relation to this point of view.
Performance of a dual anode nickel-hydrogen cell
NASA Technical Reports Server (NTRS)
Gahn, Randall F.
1991-01-01
An experimental study was conducted to characterize the voltage performance of a nickel hydrogen cell containing a hydrogen electrode on both sides of the nickel electrode. The dual anode cell was compared with a convenient single anode cell using the same nickel electrode. Higher discharge voltages and lower charge voltages were obtained with the dual anode cell during constant current discharges to 10C, pulse discharges to 8C, and polarization measurements at 50 percent of charge.
Deformed twistors and higher spin conformal (super-)algebras in four dimensions
NASA Astrophysics Data System (ADS)
Govil, Karan; Günaydin, Murat
2015-03-01
Massless conformal scalar field in d = 4 corresponds to the minimal unitary representation (minrep) of the conformal group SU(2, 2) which admits a one-parameter family of deformations that describe massless fields of arbitrary helicity. The minrep and its deformations were obtained by quantization of the nonlinear realization of SU(2, 2) as a quasiconformal group in arXiv:0908.3624. We show that the generators of SU(2,2) for these unitary irreducible representations can be written as bilinears of deformed twistorial oscillators which transform nonlinearly under the Lorentz group and apply them to define and study higher spin algebras and superalgebras in AdS 5. The higher spin (HS) algebra of Fradkin-Vasiliev type in AdS 5 is simply the enveloping algebra of SU(2, 2) quotiented by a two-sided ideal (Joseph ideal) which annihilates the minrep. We show that the Joseph ideal vanishes identically for the quasiconformal realization of the minrep and its enveloping algebra leads directly to the HS algebra in AdS 5. Furthermore, the enveloping algebras of the deformations of the minrep define a one parameter family of HS algebras in AdS 5 for which certain 4 d covariant deformations of the Joseph ideal vanish identically. These results extend to superconformal algebras SU(2, 2| N) and we find a one parameter family of HS superalgebras as enveloping algebras of the minimal unitary supermultiplet and its deformations. Our results suggest the existence of a family of (supersymmetric) HS theories in AdS 5 which are dual to free (super)conformal field theories (CFTs) or to interacting but integrable (supersymmetric) CFTs in 4 d. We also discuss the corresponding picture in HS algebras in AdS 4 where the corresponding 3 d conformal group admits only two massless representations (minreps), namely the scalar and spinor singletons.
Deformed twistors and higher spin conformal (super-)algebras in six dimensions
NASA Astrophysics Data System (ADS)
Govil, Karan; Günaydin, Murat
2014-07-01
Massless conformal scalar field in six dimensions corresponds to the minimal unitary representation (minrep) of the conformal group SO(6, 2). This minrep admits a family of "deformations" labelled by the spin t of an SU(2) T group, which is the 6 d analog of helicity in four dimensions. These deformations of the minrep of SO(6 , 2) describe massless conformal fields that are symmetric tensors in the spinorial representation of the 6 d Lorentz group. The minrep and its deformations were obtained by quantization of the nonlinear realization of SO(6 , 2) as a quasiconformal group in arXiv:1005.3580. We give a novel reformulation of the generators of SO(6 , 2) for these representations as bilinears of deformed twistorial oscillators which transform nonlinearly under the Lorentz group SO(5 , 1) and apply them to define higher spin algebras and superalgebras in AdS 7. The higher spin (HS) algebra of Fradkin-Vasiliev type in AdS 7 is simply the enveloping algebra of SO(6 , 2) quotiented by a two-sided ideal (Joseph ideal) which annihilates the minrep. We show that the Joseph ideal vanishes identically for the quasiconformal realization of the minrep and its enveloping algebra leads directly to the HS algebra in AdS 7. Furthermore, the enveloping algebras of the deformations of the minrep define a discrete infinite family of HS algebras in AdS 7 for which certain 6 d Lorentz covariant deformations of the Joseph ideal vanish identically. These results extend to superconformal algebras OSp(8*|2 N ) and we find a discrete infinite family of HS superalgebras as enveloping algebras of the minimal unitary supermultiplet and its deformations. Our results suggest the existence of a discrete family of (supersymmetric) HS theories in AdS 7 which are dual to free (super)conformal field theories (CFTs) or to interacting but integrable (supersymmetric) CFTs in 6 d.
Data Representations for Geographic Information Systems.
ERIC Educational Resources Information Center
Shaffer, Clifford A.
1992-01-01
Surveys the field and literature of geographic information systems (GIS) and spatial data representation as it relates to GIS. Highlights include GIS terms, data types, and operations; vector representations and raster, or grid, representations; spatial indexing; elevation data representations; large spatial databases; and problem areas and future…
Relativity of representations in quantum mechanics
NASA Astrophysics Data System (ADS)
de la Torre, A. C.
2002-03-01
Only the position representation is used in introductory quantum mechanics and the momentum representation is not usually presented until advanced undergraduate courses. To emphasize the relativity of the representations of the abstract formulation of quantum mechanics, two examples of representations related to the operators αX+(1-α)P and 1/2(XP+PX) are presented.
Culture as shared cognitive representations.
Romney, A K; Boyd, J P; Moore, C C; Batchelder, W H; Brazill, T J
1996-01-01
Culture consists of shared cognitive representations in the minds of individuals. This paper investigates the extent to which English speakers share the "same" semantic structure of English kinship terms. The semantic structure is defined as the arrangement of the terms relative to each other as represented in a metric space in which items judged more similar are placed closer to each other than items judged as less similar. The cognitive representation of the semantic structure, residing in the mind of an individual, is measured by judged similarity tasks involving comparisons among terms. Using six independent measurements, from each of 122 individuals, correspondence analysis represents the data in a common multidimensional spatial representation. Judged by a variety of statistical procedures, the individuals in our sample share virtually identical cognitive representations of the semantic structure of kinship terms. This model of culture accounts for 70-90% of the total variability in these data. We argue that our findings on kinship should generalize to all semantic domains--e.g., animals, emotions, etc. The investigation of semantic domains is important because they may reside in localized functional units in the brain, because they relate to a variety of cognitive processes, and because they have the potential to provide methods for diagnosing individual breakdowns in the structure of cognitive representations typical of such ailments as Alzheimer disease. PMID:11607678
Dual-throat thruster thermal model
NASA Technical Reports Server (NTRS)
Ewen, R. L.; Obrien, C. J.; Matthews, L. W.
1986-01-01
The dual-throat engine is one of the dual nozzle engine concepts studied for advanced space transportation applications. It provides a thrust change and an in-flight area ratio change through the use of two concentric combustors with their throats arranged in series. Test results are presented for a dual throat thruster burning gaseous oxygen and hydrogen at primary (inner) chamber pressures from 380 to 680 psia. Heat flux profiles were obtained from calorimetric cooling channels in the inner nozzle, outer or secondary chamber and the tip of the inner nozzle. Data were obtained for two nozzle spacings over a chamber pressure ratio (secondary/primary) range of 0.45 to 0.83 with both chambers firing (Mode I). Fluxes near the end of the inner nozzle were significantly higher than in Mode II when only the inner chamber was fired, due to the flow separation and recirculation caused by the back pressure imposed by the secondary chamber. As the pressure ratio increased, these heat fluxes increased and the region of high heat flux relative to Mode II extended farther upstream. The use of the gaseous hydrogen bleed flow in the secondary chamber to control heat fluxes in the primary plume attachment region was investigated in Mode II testing. A thermal model of a dual throat thruster was developed and upgraded using the experimental data.
On push-forward representations in the standard gyrokinetic model
Miyato, N. Yagi, M.; Scott, B. D.
2015-01-15
Two representations of fluid moments in terms of a gyro-center distribution function and gyro-center coordinates, which are called push-forward representations, are compared in the standard electrostatic gyrokinetic model. In the representation conventionally used to derive the gyrokinetic Poisson equation, the pull-back transformation of the gyro-center distribution function contains effects of the gyro-center transformation and therefore electrostatic potential fluctuations, which is described by the Poisson brackets between the distribution function and scalar functions generating the gyro-center transformation. Usually, only the lowest order solution of the generating function at first order is considered to explicitly derive the gyrokinetic Poisson equation. This is true in explicitly deriving representations of scalar fluid moments with polarization terms. One also recovers the particle diamagnetic flux at this order because it is associated with the guiding-center transformation. However, higher-order solutions are needed to derive finite Larmor radius terms of particle flux including the polarization drift flux from the conventional representation. On the other hand, the lowest order solution is sufficient for the other representation, in which the gyro-center transformation part is combined with the guiding-center one and the pull-back transformation of the distribution function does not appear.
ERIC Educational Resources Information Center
Vigliocco, Gabriella; Kousta, Stavroula; Vinson, David; Andrews, Mark; Del Campo, Elena
2013-01-01
In Kousta, Vigliocco, Vinson, Andrews, and Del Campo (2011), we presented an embodied theory of semantic representation, which crucially included abstract concepts as internally embodied via affective states. Paivio (2013) took issue with our treatment of dual coding theory, our reliance on data from lexical decision, and our theoretical proposal.…
No Telescoping Effect with Dual Tendon Vibration
Bellan, Valeria; Wallwork, Sarah B.; Stanton, Tasha R.; Reverberi, Carlo; Gallace, Alberto; Moseley, G. Lorimer
2016-01-01
The tendon vibration illusion has been extensively used to manipulate the perceived position of one’s own body part. However, findings from previous research do not seem conclusive sregarding the perceptual effect of the concurrent stimulation of both agonist and antagonist tendons over one joint. On the basis of recent data, it has been suggested that this paired stimulation generates an inconsistent signal about the limb position, which leads to a perceived shrinkage of the limb. However, this interesting effect has never been replicated. The aim of the present study was to clarify the effect of a simultaneous and equal vibration of the biceps and triceps tendons on the perceived location of the hand. Experiment 1 replicated and extended the previous findings. We compared a dual tendon stimulation condition with single tendon stimulation conditions and with a control condition (no vibration) on both ‘upward-downward’ and ‘towards-away from the elbow’ planes. Our results show a mislocalisation towards the elbow of the position of the vibrated arm during dual vibration, in line with previous results; however, this did not clarify whether the effect was due to arm representation contraction (i.e., a ‘telescoping’ effect). Therefore, in Experiment 2 we investigated explicitly and implicitly the perceived arm length during the same conditions. Our results clearly suggest that in all the vibration conditions there was a mislocalisation of the entire arm (including the elbow), but no evidence of a contraction of the perceived arm length. PMID:27305112
Assimilation of Dual-Polarimetric Radar Observations with WRF GSI
NASA Technical Reports Server (NTRS)
Li, Xuanli; Mecikalski, John; Fehnel, Traci; Zavodsky, Bradley; Srikishen, Jayanthi
2014-01-01
Dual-polarimetric (dual-pol) radar typically transmits both horizontally and vertically polarized radio wave pulses. From the two different reflected power returns, more accurate estimate of liquid and solid cloud and precipitation can be provided. The upgrade of the traditional NWS WSR-88D radar to include dual-pol capabilities will soon be completed for the entire NEXRAD network. Therefore, the use of dual-pol radar network will have a broad impact in both research and operational communities. The assimilation of dual-pol radar data is especially challenging as few guidelines have been provided by previous research. It is our goal to examine how to best use dual-pol radar data to improve forecast of severe storm and forecast initialization. In recent years, the Development Testbed Center (DTC) has released the community Gridpoint Statistical Interpolation (GSI) DA system for the Weather Research and Forecasting (WRF) model. The community GSI system runs in independently environment, yet works functionally equivalent to operational centers. With collaboration with the NASA Short-term Prediction Research and Transition (SPoRT) Center, this study explores regional assimilation of the dual-pol radar variables from the WSR-88D radars for real case storms. Our presentation will highlight our recent effort on incorporating the horizontal reflectivity (ZH), differential reflectivity (ZDR), specific differential phase (KDP), and radial velocity (VR) data for initializing convective storms, with a significant focus being on an improved representation of hydrometeor fields. In addition, discussion will be provided on the development of enhanced assimilation procedures in the GSI system with respect to dual-pol variables. Beyond the dual-pol variable assimilation procedure developing within a GSI framework, highresolution (=1 km) WRF model simulations and storm scale data assimilation experiments will be examined, emphasizing both model initialization and short-term forecast
Turning Symbolic: The Representation of Motion Direction in Working Memory
Seidel Malkinson, Tal; Pertzov, Yoni; Zohary, Ehud
2016-01-01
What happens to the representation of a moving stimulus when it is no longer present and its motion direction has to be maintained in working memory (WM)? Is the initial, sensorial representation maintained during the delay period or is there another representation, at a higher level of abstraction? It is also feasible that multiple representations may co-exist in WM, manifesting different facets of sensory and more abstract features. To that end, we investigated the mnemonic representation of motion direction in a series of three psychophysical experiments, using a delayed motion-discrimination task (relative clockwise∖counter-clockwise judgment). First, we show that a change in the dots’ contrast polarity does not hamper performance. Next, we demonstrate that performance is unaffected by relocation of the Test stimulus in either retinotopic or spatiotopic coordinate frames. Finally, we show that an arrow-shaped cue presented during the delay interval between the Sample and Test stimulus, strongly biases performance toward the direction of the arrow, although the cue itself is non-informative (it has no predictive value of the correct answer). These results indicate that the representation of motion direction in WM could be independent of the physical features of the stimulus (polarity or position) and has non-sensorial abstract qualities. It is plausible that an abstract mnemonic trace might be activated alongside a more basic, analog representation of the stimulus. We speculate that the specific sensitivity of the mnemonic representation to the arrow-shaped symbol may stem from the long term learned association between direction and the hour in the clock. PMID:26909059
Interferometric seismoelectric Green's function representations
NASA Astrophysics Data System (ADS)
de Ridder, Sjoerd A. L.; Slob, Evert; Wapenaar, Kees
2009-09-01
Interferometric Green's function representations can be used to retrieve a Green's function between two receiver stations, effectively turning one receiver into a source. Through reciprocity theorems of the convolution and correlation types, we derive interferometric Green's function representations for coupled electromagnetic and seismic wave propagation in 1-D. These representations express a symmetrized Green's function in terms of correlations of sources distributed throughout the domain of reciprocity and on its boundary. The main challenge for practical implementation is the necessity of sources throughout a domain. Numerical examples show how this constraint can be relaxed for different configurations. In a configuration of two layers bounded by a vacuum, seismic noise sources behind the interface can be used to recover seismoelectric reflection responses that suffer from small amplitude losses, but are not corrupted by spurious events.
Representation of Ideal Magnetohydrodynamic Modes
Roscoe B. White
2013-01-15
One of the most fundamental properties of ideal magnetohydrodynamics is the condition that plasma motion cannot change magnetic topology. The conventional representation of ideal magnetohydrodynamic modes by perturbing a toroidal equilibrium field through δ Β = ∇ X (xi X B) ensures that δ B • ∇ ψ = 0 at a resonance, with ψ labelling an equilibrium flux surface. Also useful for the analysis of guiding center orbits in a perturbed field is the representation δ Β = ∇ X αB. These two representations are equivalent, but the vanishing of δ B • ∇ψ at a resonance is necessary but not sufficient for the preservation of field line topology, and a indiscriminate use of either perturbation in fact destroys the original equilibrium flux topology. It is necessary to find the perturbed field to all orders in xi to conserve the original topology. The effect of using linearized perturbations on stability and growth rate calculations is discussed
Assessing value representation in animals.
San-Galli, Aurore; Bouret, Sebastien
2015-01-01
Among all factors modulating our motivation to perform a given action, the ability to represent its outcome is clearly the most determining. Representation of outcomes, rewards in particular, and how they guide behavior, have sparked much research. Both practically and theoretically, understanding the relationship between the representation of outcome value and the organization of goal directed behavior implies that these two processes can be assessed independently. Most of animal studies essentially used instrumental actions as a proxy for the expected goal-value. The purpose of this article is to consider alternative measures of expected outcome value in animals, which are critical to understand the behavioral and neurobiological mechanisms relating the representation of the expected outcome to the organization of the behavior oriented towards its obtention. This would be critical in the field of decision making or social interactions, where the value of multiple items must often be compared and/or shared among individuals to determine the course of actions. PMID:25092260
Social representations of female orgasm.
Lavie-Ajayi, Maya; Joffe, Hélène
2009-01-01
This study examines women's social representations of female orgasm. Fifty semi-structured interviews were conducted with British women. The data were thematically analysed and compared with the content of female orgasm-related writing in two women's magazines over a 30-year period. The results indicate that orgasm is deemed the goal of sex with emphasis on its physiological dimension. However, the women and the magazines graft onto this scientifically driven representation the importance of relational and emotive aspects of orgasm. For the women, particularly those who experience themselves as having problems with orgasm, the scientifically driven representations induce feelings of failure, but are also resisted. The findings highlight the role played by the social context in women's subjective experience of their sexual health. PMID:19129342
Learning multiple layers of representation.
Hinton, Geoffrey E
2007-10-01
To achieve its impressive performance in tasks such as speech perception or object recognition, the brain extracts multiple levels of representation from the sensory input. Backpropagation was the first computationally efficient model of how neural networks could learn multiple layers of representation, but it required labeled training data and it did not work well in deep networks. The limitations of backpropagation learning can now be overcome by using multilayer neural networks that contain top-down connections and training them to generate sensory data rather than to classify it. Learning multilayer generative models might seem difficult, but a recent discovery makes it easy to learn nonlinear distributed representations one layer at a time. PMID:17921042
Pedagogical Affordances of Multiple External Representations in Scientific Processes
NASA Astrophysics Data System (ADS)
Wu, Hsin-Kai; Puntambekar, Sadhana
2012-12-01
Multiple external representations (MERs) have been widely used in science teaching and learning. Theories such as dual coding theory and cognitive flexibility theory have been developed to explain why the use of MERs is beneficial to learning, but they do not provide much information on pedagogical issues such as how and in what conditions MERs could be introduced and used to support students' engagement in scientific processes and develop competent scientific practices (e.g., asking questions, planning investigations, and analyzing data). Additionally, little is understood about complex interactions among scientific processes and affordances of MERs. Therefore, this article focuses on pedagogical affordances of MERs in learning environments that engage students in various scientific processes. By reviewing literature in science education and cognitive psychology and integrating multiple perspectives, this article aims at exploring (1) how MERs can be integrated with science processes due to their different affordances, and (2) how student learning with MERs can be scaffolded, especially in a classroom situation. We argue that pairing representations and scientific processes in a principled way based on the affordances of the representations and the goals of the activities is a powerful way to use MERs in science education. Finally, we outline types of scaffolding that could help effective use of MERs including dynamic linking, model progression, support in instructional materials, teacher support, and active engagement.
Sequence comparison via polar coordinates representation and curve tree.
Dai, Qi; Guo, Xiaodong; Li, Lihua
2012-01-01
Sequence comparison has become one of the essential bioinformatics tools in bioinformatics research, which could serve as evidence of structural and functional conservation, as well as of evolutionary relations among the sequences. Existing graphical representation methods have achieved promising results in sequence comparison, but there are some design challenges with the graphical representations and feature-based measures. We reported here a new method for sequence comparison. It considers whole distribution of dual bases and employs polar coordinates method to map a biological sequence into a closed curve. The curve tree was then constructed to numerically characterize the closed curve of biological sequences, and further compared biological sequences by evaluating the distance of the curve tree of the query sequence matching against a corresponding curve tree of the template sequence. The proposed method was tested by phylogenetic analysis, and its performance was further compared with alignment-based methods. The results demonstrate that using polar coordinates representation and curve tree to compare sequences is more efficient. PMID:22001081
Representation Theory over Tropical Semifield and Langlands Duality
NASA Astrophysics Data System (ADS)
Gerasimov, Anton A.; Lebedev, Dimitri R.
2013-06-01
Recently we propose a class of infinite-dimensional integral representations of classical {{gl}_{ell+1}}-Whittaker functions and local Archimedean local L-factors using two-dimensional topological field theory framework. The local Archimedean Langlands duality was identified in this setting with the mirror symmetry of the underlying topological field theories. In this note we introduce elementary analogs of the Whittaker functions and the Archimedean L-factors given by U ℓ+1-equivariant symplectic volumes of appropriate Kähler U ℓ+1-manifolds. We demonstrate that the functions thus defined have a dual description as matrix elements of representations of monoids {GL_{ell+1}({R}), {R}} being the tropical semifield. We also show that the elementary Whittaker functions can be obtained from the non-Archimedean Whittaker functions over {{Q}_p} by taking the formal limit p→ 1. Hence the elementary special functions constructed in this way might be considered as functions over the mysterious field {{Q}_1}. The existence of two representations for the elementary Whittaker functions, one as an equivariant volume and the other as a matrix element, should be considered as a manifestation of a hypothetical elementary analog of the local Langlands duality for number fields. We would like to note that the elementary local L-factors coincide with L-factors introduced previously by Kurokawa.
Context representations, context functions, and the parahippocampal–hippocampal system
Rudy, Jerry W.
2009-01-01
Psychologists and neurobiologists have a long-standing interest in understanding how the context surrounding the events of our lives is represented and how it influences our behavior. The hippocampal formation emerged very early as a major contributor to how context is represented and functions. There is a large literature examining its contribution that on the surface reveals an array of conflicting outcomes and controversy. This review reveals that these conflicts can be resolved by building Nadel and Willner's dual-process theory of context representations. Two general conclusions emerge: (1) There are two neural systems that can support context representations and functions—a neocortical system composed primarily of perirhinal and postrhinal cortices and a hippocampal system that includes perirhinal, postrhinal, entorhinal cortices, and the hippocampal formation. (2) These two systems are not equivalent—some context representations and functions are uniquely supported by the hippocampal system. These conclusions are discussed in the context of canonical ideas about the special properties of the hippocampal system that enable it to make unique contributions to memory. PMID:19794181
Multiwindow Gabor-type transform for signal representation and analysis
NASA Astrophysics Data System (ADS)
Zibulski, Meir; Zeevi, Yehoshua Y.
1995-09-01
The Gabor scheme is generalized to incorporate several window functions as well as kernels other than the exponential. The properties of the sequence of representation functions are characterized by an approach based on the concept of frames. the frame operator associated with the multi-window Gabor-type frame, is examined for a rational oversampling rate by representing the frame operator as a finite order matrix-valued function in the Zak Transform domain. Completeness and frame properties of the sequence of representation functions are examined in relation to the properties of the matrix-valued function. Calculation of the frame bounds and the dual frame, as well as the issue of tight frames are considered. It is shown that the properties of the sequence of representation functions are essentially not changed by replacing the widely-used exponential kernel with other kernels. The issue of a different sampling rate for each window is also considered. The so-called Balian-Low theorem is generalized to consideration of a scheme of multi-windows, which makes it possible to overcome the constraint imposed by the original theorem in the case of a single window.
The Statistics of Visual Representation
NASA Technical Reports Server (NTRS)
Jobson, Daniel J.; Rahman, Zia-Ur; Woodell, Glenn A.
2002-01-01
The experience of retinex image processing has prompted us to reconsider fundamental aspects of imaging and image processing. Foremost is the idea that a good visual representation requires a non-linear transformation of the recorded (approximately linear) image data. Further, this transformation appears to converge on a specific distribution. Here we investigate the connection between numerical and visual phenomena. Specifically the questions explored are: (1) Is there a well-defined consistent statistical character associated with good visual representations? (2) Does there exist an ideal visual image? And (3) what are its statistical properties?
Corner detection and classification using anisotropic directional derivative representations.
Shui, Peng-Lang; Zhang, Wei-Chuan
2013-08-01
This paper proposes a corner detector and classifier using anisotropic directional derivative (ANDD) representations. The ANDD representation at a pixel is a function of the oriented angle and characterizes the local directional grayscale variation around the pixel. The proposed corner detector fuses the ideas of the contour- and intensity-based detection. It consists of three cascaded blocks. First, the edge map of an image is obtained by the Canny detector and from which contours are extracted and patched. Next, the ANDD representation at each pixel on contours is calculated and normalized by its maximal magnitude. The area surrounded by the normalized ANDD representation forms a new corner measure. Finally, the nonmaximum suppression and thresholding are operated on each contour to find corners in terms of the corner measure. Moreover, a corner classifier based on the peak number of the ANDD representation is given. Experiments are made to evaluate the proposed detector and classifier. The proposed detector is competitive with the two recent state-of-the-art corner detectors, the He & Yung detector and CPDA detector, in detection capability and attains higher repeatability under affine transforms. The proposed classifier can discriminate effectively simple corners, Y-type corners, and higher order corners. PMID:23743776
45 CFR 2543.17 - Certifications and representations.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 45 Public Welfare 4 2011-10-01 2011-10-01 false Certifications and representations. 2543.17 Section 2543.17 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS,...
45 CFR 2543.17 - Certifications and representations.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 4 2010-10-01 2010-10-01 false Certifications and representations. 2543.17 Section 2543.17 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS,...
34 CFR 74.17 - Certifications and representations.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 34 Education 1 2014-07-01 2014-07-01 false Certifications and representations. 74.17 Section 74.17 Education Office of the Secretary, Department of Education ADMINISTRATION OF GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 74.17 Certifications and...
22 CFR 145.17 - Certifications and representations.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Certifications and representations. 145.17 Section 145.17 Foreign Relations DEPARTMENT OF STATE CIVIL RIGHTS GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements §...
22 CFR 145.17 - Certifications and representations.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Certifications and representations. 145.17 Section 145.17 Foreign Relations DEPARTMENT OF STATE CIVIL RIGHTS GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements §...
34 CFR 74.17 - Certifications and representations.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 34 Education 1 2012-07-01 2012-07-01 false Certifications and representations. 74.17 Section 74.17 Education Office of the Secretary, Department of Education ADMINISTRATION OF GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements §...
34 CFR 74.17 - Certifications and representations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 34 Education 1 2010-07-01 2010-07-01 false Certifications and representations. 74.17 Section 74.17 Education Office of the Secretary, Department of Education ADMINISTRATION OF GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements §...
22 CFR 145.17 - Certifications and representations.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Certifications and representations. 145.17 Section 145.17 Foreign Relations DEPARTMENT OF STATE CIVIL RIGHTS GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements §...
More than Skin Deep: Body Representation beyond Primary Somatosensory Cortex
ERIC Educational Resources Information Center
Longo, Matthew R.; Azanon, Elena; Haggard, Patrick
2010-01-01
The neural circuits underlying initial sensory processing of somatic information are relatively well understood. In contrast, the processes that go beyond primary somatosensation to create more abstract representations related to the body are less clear. In this review, we focus on two classes of higher-order processing beyond Somatosensation.…
A verification logic representation of indeterministic signal states
NASA Technical Reports Server (NTRS)
Gambles, J. W.; Windley, P. J.
1991-01-01
The integration of modern CAD tools with formal verification environments require translation from hardware description language to verification logic. A signal representation including both unknown state and a degree of strength indeterminacy is essential for the correct modeling of many VLSI circuit designs. A higher-order logic theory of indeterministic logic signals is presented.
36 CFR 1210.17 - Certifications and representations.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Certifications and representations. 1210.17 Section 1210.17 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL RULES UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND...
36 CFR 1210.17 - Certifications and representations.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Certifications and representations. 1210.17 Section 1210.17 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL RULES UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND...
36 CFR 1210.17 - Certifications and representations.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Certifications and representations. 1210.17 Section 1210.17 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL RULES UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND...
36 CFR 1210.17 - Certifications and representations.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Certifications and representations. 1210.17 Section 1210.17 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL RULES UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND...
36 CFR 1210.17 - Certifications and representations.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Certifications and representations. 1210.17 Section 1210.17 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL RULES UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND AGREEMENTS WITH INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, AND OTHER...
Students Protest Lack of Representation at Spellings Summit
ERIC Educational Resources Information Center
Smith, Lauren
2007-01-01
Student lobbyists have sent Secretary of Education Margaret Spellings a letter scolding her for what they see as a minimizing of student representation at the higher-education summit held last week. The Department of Education responded by saying that students had indeed been invited to participate. The letter, which was signed by Jennifer S. Pae,…
NASA Astrophysics Data System (ADS)
Taniguchi, Tadahiro; Sawaragi, Tetsuo
In this paper, a new machine-learning method, called Dual-Schemata model, is presented. Dual-Schemata model is a kind of self-organizational machine learning methods for an autonomous robot interacting with an unknown dynamical environment. This is based on Piaget's Schema model, that is a classical psychological model to explain memory and cognitive development of human beings. Our Dual-Schemata model is developed as a computational model of Piaget's Schema model, especially focusing on sensori-motor developing period. This developmental process is characterized by a couple of two mutually-interacting dynamics; one is a dynamics formed by assimilation and accommodation, and the other dynamics is formed by equilibration and differentiation. By these dynamics schema system enables an agent to act well in a real world. This schema's differentiation process corresponds to a symbol formation process occurring within an autonomous agent when it interacts with an unknown, dynamically changing environment. Experiment results obtained from an autonomous facial robot in which our model is embedded are presented; an autonomous facial robot becomes able to chase a ball moving in various ways without any rewards nor teaching signals from outside. Moreover, emergence of concepts on the target movements within a robot is shown and discussed in terms of fuzzy logics on set-subset inclusive relationships.
ERIC Educational Resources Information Center
Scharf, Miri
2001-01-01
Explored long-term effects of different childrearing contexts on attachment and separation representations of Israeli 16- to 18-year-olds. Found that adolescents raised in a kibbutz communal setting showed higher incidence of nonautonomous attachment representations and less competent coping with imagined separations than adolescents raised in a…
Graphical Representation of Complex Solutions of the Quadratic Equation in the "xy" Plane
ERIC Educational Resources Information Center
McDonald, Todd
2006-01-01
This paper presents a visual representation of complex solutions of quadratic equations in the xy plane. Rather than moving to the complex plane, students are able to experience a geometric interpretation of the solutions in the xy plane. I am also working on these types of representations with higher order polynomials with some success.
The Changing Role of Students' Representation in Poland: An Historical Appraisal
ERIC Educational Resources Information Center
Antonowicz, Dominik; Pinheiro, Rómulo; Smuzewska, Marcelina
2014-01-01
Student representation in Poland has a relatively short but turbulent history. This article offers an historical appraisal of the development of student representation at the national level in the context of rapid and deep structural changes in Polish higher education. Based on a desktop analysis of official documentation, legislation, ideological…
Correct Representation of Conformational Equilibria.
ERIC Educational Resources Information Center
Fulop, F.; And Others
1983-01-01
In representing conformational equilibria of compounds having only one chiral center, erroneous formulas showing different antipodes on the two sides of the equilibrium are rare. In contrast, with compounds having two or more chiral centers especially with saturated heterocycles, this erroneous representation occurs frequently in the chemical…
Representational Momentum in Older Adults
ERIC Educational Resources Information Center
Piotrowski, Andrea S.; Jakobson, Lorna S.
2011-01-01
Humans have a tendency to perceive motion even in static images that simply "imply" movement. This tendency is so strong that our memory for actions depicted in static images is distorted in the direction of implied motion--a phenomenon known as representational momentum (RM). In the present study, we created an RM display depicting a pattern of…