Anne B Sereno
2011-02-01
Full Text Available Although the representation of space is as fundamental to visual processing as the representation of shape, it has received relatively little attention from neurophysiological investigations. In this study we characterize representations of space within visual cortex, and examine how they differ in a first direct comparison between dorsal and ventral subdivisions of the visual pathways. Neural activities were recorded in anterior inferotemporal cortex (AIT and lateral intraparietal cortex (LIP of awake behaving monkeys, structures associated with the ventral and dorsal visual pathways respectively, as a stimulus was presented at different locations within the visual field. In spatially selective cells, we find greater modulation of cell responses in LIP with changes in stimulus position. Further, using a novel population-based statistical approach (namely, multidimensional scaling, we recover the spatial map implicit within activities of neural populations, allowing us to quantitatively compare the geometry of neural space with physical space. We show that a population of spatially selective LIP neurons, despite having large receptive fields, is able to almost perfectly reconstruct stimulus locations within a low-dimensional representation. In contrast, a population of AIT neurons, despite each cell being spatially selective, provide less accurate low-dimensional reconstructions of stimulus locations. They produce instead only a topologically (categorically correct rendition of space, which nevertheless might be critical for object and scene recognition. Furthermore, we found that the spatial representation recovered from population activity shows greater translation invariance in LIP than in AIT. We suggest that LIP spatial representations may be dimensionally isomorphic with 3D physical space, while in AIT spatial representations may reflect a more categorical representation of space (e.g., next to or above.
Młynarski, Wiktor
2015-05-01
In mammalian auditory cortex, sound source position is represented by a population of broadly tuned neurons whose firing is modulated by sounds located at all positions surrounding the animal. Peaks of their tuning curves are concentrated at lateral position, while their slopes are steepest at the interaural midline, allowing for the maximum localization accuracy in that area. These experimental observations contradict initial assumptions that the auditory space is represented as a topographic cortical map. It has been suggested that a "panoramic" code has evolved to match specific demands of the sound localization task. This work provides evidence suggesting that properties of spatial auditory neurons identified experimentally follow from a general design principle- learning a sparse, efficient representation of natural stimuli. Natural binaural sounds were recorded and served as input to a hierarchical sparse-coding model. In the first layer, left and right ear sounds were separately encoded by a population of complex-valued basis functions which separated phase and amplitude. Both parameters are known to carry information relevant for spatial hearing. Monaural input converged in the second layer, which learned a joint representation of amplitude and interaural phase difference. Spatial selectivity of each second-layer unit was measured by exposing the model to natural sound sources recorded at different positions. Obtained tuning curves match well tuning characteristics of neurons in the mammalian auditory cortex. This study connects neuronal coding of the auditory space with natural stimulus statistics and generates new experimental predictions. Moreover, results presented here suggest that cortical regions with seemingly different functions may implement the same computational strategy-efficient coding.
Wiktor Młynarski
2015-05-01
Full Text Available In mammalian auditory cortex, sound source position is represented by a population of broadly tuned neurons whose firing is modulated by sounds located at all positions surrounding the animal. Peaks of their tuning curves are concentrated at lateral position, while their slopes are steepest at the interaural midline, allowing for the maximum localization accuracy in that area. These experimental observations contradict initial assumptions that the auditory space is represented as a topographic cortical map. It has been suggested that a "panoramic" code has evolved to match specific demands of the sound localization task. This work provides evidence suggesting that properties of spatial auditory neurons identified experimentally follow from a general design principle- learning a sparse, efficient representation of natural stimuli. Natural binaural sounds were recorded and served as input to a hierarchical sparse-coding model. In the first layer, left and right ear sounds were separately encoded by a population of complex-valued basis functions which separated phase and amplitude. Both parameters are known to carry information relevant for spatial hearing. Monaural input converged in the second layer, which learned a joint representation of amplitude and interaural phase difference. Spatial selectivity of each second-layer unit was measured by exposing the model to natural sound sources recorded at different positions. Obtained tuning curves match well tuning characteristics of neurons in the mammalian auditory cortex. This study connects neuronal coding of the auditory space with natural stimulus statistics and generates new experimental predictions. Moreover, results presented here suggest that cortical regions with seemingly different functions may implement the same computational strategy-efficient coding.
Representation of Fuzzy Symmetric Relations
1986-03-19
Std Z39-18 REPRESENTATION OF FUZZY SYMMETRIC RELATIONS L. Valverde Dept. de Matematiques i Estadistica Universitat Politecnica de Catalunya Avda...REPRESENTATION OF FUZZY SYMMETRIC RELATIONS L. "Valverde* Dept. de Matematiques i Estadistica Universitat Politecnica de Catalunya Avda. Diagonal, 649
Transforming Graph Representations for Statistical Relational Learning
Rossi, Ryan A; Aha, David W; Neville, Jennifer
2012-01-01
Relational data representations have become an increasingly important topic due to the recent proliferation of network datasets (e.g., social, biological, information networks) and a corresponding increase in the application of statistical relational learning (SRL) algorithms to these domains. In this article, we examine a range of representation issues for graph-based relational data. Since the choice of relational data representation for the nodes, links, and features can dramatically affect the capabilities of SRL algorithms, we survey approaches and opportunities for relational representation transformation designed to improve the performance of these algorithms. This leads us to introduce an intuitive taxonomy for data representation transformations in relational domains that incorporates link transformation and node transformation as symmetric representation tasks. In particular, the transformation tasks for both nodes and links include (i) predicting their existence, (ii) predicting their label or type...
Relational Representations of Strongly Algebraic Lattices
XU Guang-hong; RAO San-ping
2012-01-01
In this paper,we introduce and investigate the strongly regular relation.Then we give the relational representations and an intrinsic characterization of strongly algebraic lattices via mapping relation and strongly regular relation.
Population coding of somatic sensations
Qiufu Ma
2012-01-01
The somatic sensory system includes a variety of sensory modalities,such as touch,pain,itch,and temperature sensitivity.The coding of these modalities appears to be best explained by the population-coding theory,which is composed of the following features.First,an individual somatic sensory afferent is connected with a specific neural circuit or network (for simplicity,a sensory-labeled line),whose isolated activation is sufficient to generate one specific sensation under normal conditions.Second,labeled lines are interconnected through local excitatory and inhibitory interneurons.As a result,activation of one labeled line could modulate,or provide gate control of,another labeled line.Third,most sensory fibers are polymodal,such that a given stimulus placed onto the skin often activates two or multiple sensory-labeled lines;crosstalk among them is needed to generate one dominant sensation.Fourth and under pathological conditions,a disruption of the antagonistic interaction among labeled lines could open normally masked neuronal pathways,and allow a given sensory stimulus to evoke a new sensation,such as pain evoked by innocuous mechanical or thermal stimuli and itch evoked by painful stimuli.As a result of this,some sensory fibers operate along distinct labeled lines under normal versus pathological conditions.Thus,a better understanding of the neural network underlying labeled line crosstalk may provide new strategies to treat chronic pain and itch.
Some Representation Theorems for Recovering Contraction Relations
Ping Hou
2005-01-01
One of the important topics in the study of contraction inference relations is to establish the representation theorems for them. Various methods have been employed for giving representation of a broad class of contraction operations.However, there was not any canonical approach to dealing with the representation results for the contraction relations in the literature. Recently, in order to obtain the representation result for recovering contraction inference relations satisfying the condition weak conjunctive inclusion (wci), a notion of an image structure associated with the canonical epistemic state has been introduced. Based on the image structure, this paper establishes three representation results for recovering contraction inference relations which satisfy the conditions CL, CR1 and DR* respectively by the standard epistemic AGM states. A unique technique and uniform proofs to represent these contraction relations are adopted, which could overcome the core objection in previous description of contraction relations. The paper shows as well that the image structure and canonical epistemic states can be used not only to get the representation result for wci-recovering contraction relation, but also to provide semantic characterizations for a wide range of recovering contraction relations.
Narcissism and relational representations among psychiatric outpatients.
Kealy, David; Ogrodniczuk, John S; Joyce, Anthony S; Steinberg, Paul I; Piper, William E
2015-06-01
Pathological narcissism is associated with maladaptive interpersonal behavior, although less is known regarding the internal relational representations of narcissistic patients. The authors examined the relationship between pathological narcissism and two constructs that reflect internal representations of relational patterns: quality of object relations and attachment style. Patients attending a psychiatric day treatment program (N = 218) completed measures of narcissism, general psychiatric distress, and attachment style in terms of attachment avoidance and anxiety. A semistructured interview was used to assess quality of object relations. Multiple regression analysis was conducted, controlling for general psychiatric distress. Pathological narcissism was associated with anxious attachment, but not with avoidant attachment. Narcissism was also associated with lower levels of quality of object relations. The implications of these results are discussed in terms of internal representations of self-other relations.
Ambiguous representations as fuzzy relations between sets
Nykyforchyn, Oleh; 10.1016/j.fss.2011.02.007
2011-01-01
Crisp and $L$-fuzzy ambiguous representations of closed subsets of one space by closed subsets of another space are introduced. It is shown that, for each pair of compact Hausdorff spaces, the set of (crisp or $L$-fuzzy) ambiguous representations is a lattice and a compact Hausdorff Lawson upper semilattice. The categories of ambiguous and $L$-ambiguous representations are defined and investigated.
Relations between asymptotic and Fredholm representations
Manuilov, V M
1997-01-01
We prove that for matrix algebras $M_n$ there exists a monomorphism $(\\prod_n M_n/\\oplus_n M_n)\\otimes C(S^1) \\to {\\cal Q} $ into the Calkin algebra which induces an isomorphism of the $K_1$-groups. As a consequence we show that every vector bundle over a classifying space $B\\pi$ which can be obtained from an asymptotic representation of a discrete group $\\pi$ can be obtained also from a representation of the group $\\pi\\times Z$ into the Calkin algebra. We give also a generalization of the notion of Fredholm representation and show that asymptotic representations can be viewed as asymptotic Fredholm representations.
Altered Images: the relations between design representation and design practice
Susan Keller
2005-05-01
Full Text Available As information systems move out of the office into the wider world and are merged with mobile appliances, buildings and even clothing, the representations traditionally used in any one discipline may not be adequate for understanding these new domains. Design representations are ‘ways of seeing and not seeing’. Despite the central role representations play in design, the information systems design community has little understanding of the relation, ideal or actual, between design practice and design representation. This paper reports on an extensive design case study that aims at increasing understanding of the nature and affordances of representations in the design process and argues for the need for information systems as a discipline to open up discussion of the design representations that may be required to effectively design systems that mix traditional IS with disciplines such as industrial design, architecture and fashion design.
Population Code Dynamics in Categorical Perception.
Tajima, Chihiro I; Tajima, Satohiro; Koida, Kowa; Komatsu, Hidehiko; Aihara, Kazuyuki; Suzuki, Hideyuki
2016-03-03
Categorical perception is a ubiquitous function in sensory information processing, and is reported to have important influences on the recognition of presented and/or memorized stimuli. However, such complex interactions among categorical perception and other aspects of sensory processing have not been explained well in a unified manner. Here, we propose a recurrent neural network model to process categorical information of stimuli, which approximately realizes a hierarchical Bayesian estimation on stimuli. The model accounts for a wide variety of neurophysiological and cognitive phenomena in a consistent framework. In particular, the reported complexity of categorical effects, including (i) task-dependent modulation of neural response, (ii) clustering of neural population representation, (iii) temporal evolution of perceptual color memory, and (iv) a non-uniform discrimination threshold, are explained as different aspects of a single model. Moreover, we directly examine key model behaviors in the monkey visual cortex by analyzing neural population dynamics during categorization and discrimination of color stimuli. We find that the categorical task causes temporally-evolving biases in the neuronal population representations toward the focal colors, which supports the proposed model. These results suggest that categorical perception can be achieved by recurrent neural dynamics that approximates optimal probabilistic inference in the changing environment.
Age-Related Deficits in Conjunctive Representation of Complex Objects
Scheerer, Nichole; Marrone, Diano F.
2014-01-01
Although some evidence is consistent with the notion that distinct cortical systems support memory and perception, mounting evidence supports a representational-hierarchical view of cognition, which posits that distinctions lie in simple feature representations versus more complex conjunctive representations of many stimulus features simultaneously. Thus, typical memory tasks engage different regions from typical perception tasks because they inherently test information on opposing ends of this continuum. Memory deficits are reliably reported with age, but the tasks used to make these conclusions predominantly rely on conjunctive representations. To test the extent to which age-related deficits may be accounted for by perceptual processing, this study investigated discriminations involving conjunctive representations in older adults. Results show that adults aged 50 to 77 are impaired, relative to their younger counterparts, on discriminations requiring feature conjunctions, but not simple feature representations. These findings support recent data showing an agerelated decline in the ability to form conjunctive representations. Furthermore, these data suggest that some ‘mnemonic’ deficits associated with age may in fact be the result of deficits in perception rather than memory. PMID:25308561
Knowledge extraction from evolving spiking neural networks with rank order population coding.
Soltic, Snjezana; Kasabov, Nikola
2010-12-01
This paper demonstrates how knowledge can be extracted from evolving spiking neural networks with rank order population coding. Knowledge discovery is a very important feature of intelligent systems. Yet, a disproportionally small amount of research is centered on the issue of knowledge extraction from spiking neural networks which are considered to be the third generation of artificial neural networks. The lack of knowledge representation compatibility is becoming a major detriment to end users of these networks. We show that a high-level knowledge can be obtained from evolving spiking neural networks. More specifically, we propose a method for fuzzy rule extraction from an evolving spiking network with rank order population coding. The proposed method was used for knowledge discovery on two benchmark taste recognition problems where the knowledge learnt by an evolving spiking neural network was extracted in the form of zero-order Takagi-Sugeno fuzzy IF-THEN rules.
Deciphering neuronal population codes for acute thermal pain
Chen, Zhe; Zhang, Qiaosheng; Phuong Sieu Tong, Ai; Manders, Toby R.; Wang, Jing
2017-06-01
Objective. Pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. Current pain research mostly focuses on molecular and synaptic changes at the spinal and peripheral levels. However, a complete understanding of pain mechanisms requires the physiological study of the neocortex. Our goal is to apply a neural decoding approach to read out the onset of acute thermal pain signals, which can be used for brain-machine interface. Approach. We used micro wire arrays to record ensemble neuronal activities from the primary somatosensory cortex (S1) and anterior cingulate cortex (ACC) in freely behaving rats. We further investigated neural codes for acute thermal pain at both single-cell and population levels. To detect the onset of acute thermal pain signals, we developed a novel latent state-space framework to decipher the sorted or unsorted S1 and ACC ensemble spike activities, which reveal information about the onset of pain signals. Main results. The state space analysis allows us to uncover a latent state process that drives the observed ensemble spike activity, and to further detect the ‘neuronal threshold’ for acute thermal pain on a single-trial basis. Our method achieved good detection performance in sensitivity and specificity. In addition, our results suggested that an optimal strategy for detecting the onset of acute thermal pain signals may be based on combined evidence from S1 and ACC population codes. Significance. Our study is the first to detect the onset of acute pain signals based on neuronal ensemble spike activity. It is important from a mechanistic viewpoint as it relates to the significance of S1 and ACC activities in the regulation of the acute pain onset.
Representation of Integral Dispersion Relations by Local Forms
Ferreira, Erasmo
2007-01-01
The representation of the usual integral dispersion relations (IDR) of scattering theory through series of derivatives of the amplitudes is discussed, extended, simplified, and confirmed as mathematical identities. Forms of derivative dispersion relations (DDR) valid for the whole energy interval, recently obtained and presented as double infinite series, are simplified through the use of new sum rules of the incomplete $\\Gamma$ functions, being reduced to single summations, where the usual convergence criteria are easily applied. For the forms of the imaginary amplitude used in phenomenology of hadronic scattering, we show that expressions for the DDR can represent, with absolute accuracy, the IDR of scattering theory, as true mathematical identities. Besides the fact that the algebraic manipulation can be easily understood, numerical tests prove the accuracy of these representations up to the maximum available machine precision. As consequence of our analytical and numerical work, it is concluded that the s...
Asynchrony adaptation reveals neural population code for audio-visual timing.
Roach, Neil W; Heron, James; Whitaker, David; McGraw, Paul V
2011-05-01
The relative timing of auditory and visual stimuli is a critical cue for determining whether sensory signals relate to a common source and for making inferences about causality. However, the way in which the brain represents temporal relationships remains poorly understood. Recent studies indicate that our perception of multisensory timing is flexible--adaptation to a regular inter-modal delay alters the point at which subsequent stimuli are judged to be simultaneous. Here, we measure the effect of audio-visual asynchrony adaptation on the perception of a wide range of sub-second temporal relationships. We find distinctive patterns of induced biases that are inconsistent with the previous explanations based on changes in perceptual latency. Instead, our results can be well accounted for by a neural population coding model in which: (i) relative audio-visual timing is represented by the distributed activity across a relatively small number of neurons tuned to different delays; (ii) the algorithm for reading out this population code is efficient, but subject to biases owing to under-sampling; and (iii) the effect of adaptation is to modify neuronal response gain. These results suggest that multisensory timing information is represented by a dedicated population code and that shifts in perceived simultaneity following asynchrony adaptation arise from analogous neural processes to well-known perceptual after-effects.
Population Coding in Sparsely Connected Networks of Noisy Neurons
Bryan Patrick Tripp
2012-05-01
Full Text Available This study examines the relationship between population coding and spatial connection statistics in networks of noisy neurons. Encoding of sensory information in the neocortex is thought to require coordinated neural populations, because individual cortical neurons respond to a wide range of stimuli, and exhibit highly variable spiking in response to repeated stimuli. Population coding is rooted in network structure, because cortical neurons receive information only from other neurons, and because the information they encode must be decoded by other neurons, if it is to affect behaviour. However, population coding theory has often ignored network structure, or assumed discrete, fully-connected populations (in contrast with the sparsely connected, continuous sheet of the cortex. In this study, we model a sheet of cortical neurons with sparse, primarily local connections, and find that a network with this structure can encode multiple internal state variables with high signal-to-noise ratio. However, in our model, although connection probability varies with the distance between neurons, we find that the connections cannot be instantiated at random according to these probabilities, but must have additional structure if information is to be encoded with high fidelity.
On the Fock representation of the q-commutation relations
Dykema, K J; Dykema, Ken; Nica, Alexandru
1993-01-01
The q-commutation relations in the title are those that have recently received much attention, and that for -1representation of these relations on the twisted Fock space of Bozejko-Speicher, and we find a canonical unitary U_q from the twisted Fock space to usual full Fock space, such that U_q R^q (U_q)^* contains the Cuntz algebra R^0, and such that we have equality for |q|<0.44.
Note on recursion relations for the Q -cut representation
Feng, Bo; He, Song; Huang, Rijun; Luo, Ming-xing
2017-01-01
In this note, we study the Q -cut representation by combining it with BCFW deformation. As a consequence, the one-loop integrand is expressed in terms of a recursion relation, i.e., n-point one-loop integrand is constructed using tree-level amplitudes and m-point one-loop integrands with m ≤ n - 1. By giving explicit examples, we show that the integrand from the recursion relation is equivalent to that from Feynman diagrams or the original Q -cut construction, up to scale free terms.
The role of action representations in thematic object relations.
Konstantinos eTsagkaridis
2014-03-01
Full Text Available Recent studies assessing the role of associative/event-based (thematic and categorical (taxonomic relations in the organization of object representations suggest that thematic relationships may influence the perceived similarity of manipulable artifacts. At the same time, evidence suggests that action knowledge is an important component of manipulable artifact representations. However, the role that action plays in processing thematic relationships between objects is unclear. In this study, we assessed healthy and left hemisphere stroke participants to explore three questions: 1. Do participants favor thematic relations involving action (Th+A, e.g., wine bottle – corkscrew, thematic relationships without action (Th-A, e.g., wine bottle – cheese, or taxonomic relationships (Tax, e.g., wine bottle – water bottle when choosing between them in an association judgment task? 2. Do the underlying constructs of event, action, and categorical relatedness implicitly determine the choices that participants make? 3. Does degraded action knowledge and/or damage to temporo-parietal cortex (a region of the brain associated with action representations reduce the influence of action on the choice task? Experiment 1 showed that explicit ratings of event, action, and categorical relatedness differentially predicted healthy participants’ choices, with action relatedness determining choices between Th+A and Th-A associations above and beyond event and categorical ratings. Experiment 2 focused more specifically on these Th+A vs. Th-A choices and demonstrated that participants with left temporo-parietal lesions, a brain region known to be involved in sensorimotor processing, were less likely than controls, and tended to be less likely than patients with lesions sparing that region, to implicitly use action knowledge in determining their choices. We conclude that action knowledge plays a critical role in processing of thematic relations for manipulable
Jorrit Steven Montijn
2014-06-01
Full Text Available The primary visual cortex is an excellent model system for investigating how neuronal populations encode information, because of well-documented relationships between stimulus characteristics and neuronal activation patterns. We used two-photon calcium imaging data to relate the performance of different methods for studying population coding (population vectors, template matching and Bayesian decoding algorithms to their underlying assumptions. We show that the variability of neuronal responses may hamper the decoding of population activity, and that a normalization to correct for this variability may be of critical importance for correct decoding of population activity. Second, by comparing noise correlations and stimulus tuning we find that these properties have dissociated anatomical correlates, even though noise correlations have been previously hypothesized to reflect common synaptic input. We hypothesize that noise correlations arise from large nonspecific increases in spiking activity acting on many weak synapses simultaneously, while neuronal stimulus response properties are dependent on more reliable connections. Finally, this paper provides practical guidelines for further research on population coding and shows that population coding cannot be approximated by a simple summation of inputs, but is heavily influenced by factors such as input reliability and noise correlation structure.
Montijn, Jorrit S; Vinck, Martin; Pennartz, Cyriel M A
2014-01-01
The primary visual cortex is an excellent model system for investigating how neuronal populations encode information, because of well-documented relationships between stimulus characteristics and neuronal activation patterns. We used two-photon calcium imaging data to relate the performance of different methods for studying population coding (population vectors, template matching, and Bayesian decoding algorithms) to their underlying assumptions. We show that the variability of neuronal responses may hamper the decoding of population activity, and that a normalization to correct for this variability may be of critical importance for correct decoding of population activity. Second, by comparing noise correlations and stimulus tuning we find that these properties have dissociated anatomical correlates, even though noise correlations have been previously hypothesized to reflect common synaptic input. We hypothesize that noise correlations arise from large non-specific increases in spiking activity acting on many weak synapses simultaneously, while neuronal stimulus response properties are dependent on more reliable connections. Finally, this paper provides practical guidelines for further research on population coding and shows that population coding cannot be approximated by a simple summation of inputs, but is heavily influenced by factors such as input reliability and noise correlation structure.
Representation of stable social dominance relations by human infants.
Mascaro, Olivier; Csibra, Gergely
2012-05-01
What are the origins of humans' capacity to represent social relations? We approached this question by studying human infants' understanding of social dominance as a stable relation. We presented infants with interactions between animated agents in conflict situations. Studies 1 and 2 targeted expectations of stability of social dominance. They revealed that 15-mo-olds (and, to a lesser extent, 12-mo-olds) expect an asymmetric relationship between two agents to remain stable from one conflict to another. To do so, infants need to infer that one of the agents (the dominant) will consistently prevail when her goals conflict with those of the other (the subordinate). Study 3 and 4 targeted the format of infants' representation of social dominance. In these studies, we found that 12- and 15-mo-olds did not extend their expectations of dominance to unobserved relationships, even when they could have been established by transitive inference. These results suggest that infants' expectation of stability originates from their representation of social dominance as a relationship between two agents rather than as an individual property. Infants' demonstrated understanding of social dominance reflects the cognitive underpinning of humans' capacity to represent social relations, which may be evolutionarily ancient, and may be shared with nonhuman species.
Characteristics of Haptic Peripersonal Spatial Representation of Object Relations
2016-01-01
Haptic perception of space is known to show characteristics that are different to actual space. The current study extends on this line of research, investigating whether systematic deviations are also observed in the formation of haptic spatial representations of object-to-object relations. We conducted a haptic spatial reproduction task analogous to the parallelity task with spatial layouts. Three magnets were positioned to form corners of an isosceles triangle and the task of the participant was to reproduce the right angle corner. Weobserved systematic deviations in the reproduction of the right angle triangle. The systematic deviations were not observed when the task was conducted on the mid-sagittal plane. Furthermore, the magnitude of the deviation was decreased when non-informative vision was introduced. These results suggest that there is a deformation in spatial representation of object-to-object relations formed using haptics. However, as no systematic deviation was observed when the task was conducted on the mid-saggital plane, we suggest that the perception of object-to-object relations use a different egocentric reference frame to the perception of orientation. PMID:27462990
Characteristics of Haptic Peripersonal Spatial Representation of Object Relations.
Ryo Wako
Full Text Available Haptic perception of space is known to show characteristics that are different to actual space. The current study extends on this line of research, investigating whether systematic deviations are also observed in the formation of haptic spatial representations of object-to-object relations. We conducted a haptic spatial reproduction task analogous to the parallelity task with spatial layouts. Three magnets were positioned to form corners of an isosceles triangle and the task of the participant was to reproduce the right angle corner. Weobserved systematic deviations in the reproduction of the right angle triangle. The systematic deviations were not observed when the task was conducted on the mid-sagittal plane. Furthermore, the magnitude of the deviation was decreased when non-informative vision was introduced. These results suggest that there is a deformation in spatial representation of object-to-object relations formed using haptics. However, as no systematic deviation was observed when the task was conducted on the mid-saggital plane, we suggest that the perception of object-to-object relations use a different egocentric reference frame to the perception of orientation.
The relation between body semantics and spatial body representations.
van Elk, Michiel; Blanke, Olaf
2011-11-01
The present study addressed the relation between body semantics (i.e. semantic knowledge about the human body) and spatial body representations, by presenting participants with word pairs, one below the other, referring to body parts. The spatial position of the word pairs could be congruent (e.g. EYE / MOUTH) or incongruent (MOUTH / EYE) with respect to the spatial position of the words' referents. In addition, the spatial distance between the words' referents was varied, resulting in word pairs referring to body parts that are close (e.g. EYE / MOUTH) or far in space (e.g. EYE / FOOT). A spatial congruency effect was observed when subjects made an iconicity judgment (Experiments 2 and 3) but not when making a semantic relatedness judgment (Experiment 1). In addition, when making a semantic relatedness judgment (Experiment 1) reaction times increased with increased distance between the body parts but when making an iconicity judgment (Experiments 2 and 3) reaction times decreased with increased distance. These findings suggest that the processing of body-semantics results in the activation of a detailed visuo-spatial body representation that is modulated by the specific task requirements. We discuss these new data with respect to theories of embodied cognition and body semantics.
Representations of Canonical Commutation Relations Describing Infinite Coherent States
Joye, Alain; Merkli, Marco
2016-10-01
We investigate the infinite volume limit of quantized photon fields in multimode coherent states. We show that for states containing a continuum of coherent modes, it is mathematically and physically natural to consider their phases to be random and identically distributed. The infinite volume states give rise to Hilbert space representations of the canonical commutation relations which we construct concretely. In the case of random phases, the representations are random as well and can be expressed with the help of Itô stochastic integrals. We analyze the dynamics of the infinite state alone and the open system dynamics of small systems coupled to it. We show that under the free field dynamics, initial phase distributions are driven to the uniform distribution. We demonstrate that coherences in small quantum systems, interacting with the infinite coherent state, exhibit Gaussian time decay. The decoherence is qualitatively faster than the one caused by infinite thermal states, which is known to be exponentially rapid only. This emphasizes the classical character of coherent states.
Learning to Estimate Dynamical State with Probabilistic Population Codes.
Joseph G Makin
2015-11-01
Full Text Available Tracking moving objects, including one's own body, is a fundamental ability of higher organisms, playing a central role in many perceptual and motor tasks. While it is unknown how the brain learns to follow and predict the dynamics of objects, it is known that this process of state estimation can be learned purely from the statistics of noisy observations. When the dynamics are simply linear with additive Gaussian noise, the optimal solution is the well known Kalman filter (KF, the parameters of which can be learned via latent-variable density estimation (the EM algorithm. The brain does not, however, directly manipulate matrices and vectors, but instead appears to represent probability distributions with the firing rates of population of neurons, "probabilistic population codes." We show that a recurrent neural network-a modified form of an exponential family harmonium (EFH-that takes a linear probabilistic population code as input can learn, without supervision, to estimate the state of a linear dynamical system. After observing a series of population responses (spike counts to the position of a moving object, the network learns to represent the velocity of the object and forms nearly optimal predictions about the position at the next time-step. This result builds on our previous work showing that a similar network can learn to perform multisensory integration and coordinate transformations for static stimuli. The receptive fields of the trained network also make qualitative predictions about the developing and learning brain: tuning gradually emerges for higher-order dynamical states not explicitly present in the inputs, appearing as delayed tuning for the lower-order states.
Fazio, Lisa K.; Bailey, Drew H.; Thompson, Clarissa A.; Siegler, Robert S.
2014-01-01
We examined relations between symbolic and non-symbolic numerical magnitude representations, between whole number and fraction representations, and between these representations and overall mathematics achievement in fifth graders. Fraction and whole number symbolic and non-symbolic numerical magnitude understandings were measured using both…
Emerging principles of population coding: in search for the neural code.
Shamir, Maoz
2014-04-01
Population coding theory aims to provide quantitative tests for hypotheses concerning the neural code. Over the last two decades theory has focused on analyzing the ways in which various parameters that characterize neuronal responses to external stimuli affect the information content of these responses. This article reviews and provides an intuitive explanation for the major effects of noise correlations and neuronal heterogeneity, and discusses their implications for our ability to investigate the neural code. It is argued that to test neural code hypotheses further, additional constraints are required, including relating trial-to-trial variation in neuronal population responses to behavioral decisions and specifying how information is decoded by downstream networks.
Attachment Representations and Characteristics of Friendship Relations during Adolescence
Zimmermann, Peter
2004-01-01
Attachment theory proposes that experiences with the primary caregivers are an important basis for the development of close social relationships outside the parent-child relationship. This study examined the association between representations of attachment, as assessed with the Adult Attachment Interview (AAI), representations of friendship and…
Fock representations of Q-deformed commutation relations
BoŻejko, Marek; Lytvynov, Eugene; Wysoczański, Janusz
2017-07-01
We consider Fock representations of the Q-deformed commutation relations ∂s∂t†=Q (s ,t ) ∂t†∂s+δ (s ,t ) for s ,t ∈T . Here T :=Rd (or more generally T is a locally compact Polish space), the function Q :T2→C satisfies |Q (s ,t ) |≤1 and Q (s ,t ) =Q (t ,s ) ¯ , and ∫T2h (s ) g (t ) δ (s ,t ) σ (d s ) σ (d t ) :=∫Th (t ) g (t ) σ (d t ) , σ being a fixed reference measure on T. In the case, where |Q (s ,t ) |≡1 , the Q-deformed commutation relations describe a generalized statistics studied by Liguori and Mintchev. These generalized statistics contain anyon statistics as a special case (with T =R2 and a special choice of the function Q). The related Q-deformed Fock space F (H ) over H :=L2(T →C ,σ ) is constructed. An explicit form of the orthogonal projection of H⊗n onto the n-particle space Fn(H ) is derived. A scalar product in Fn(H ) is given by an operator Pn≥0 in H⊗n which is strictly positive on Fn(H ) . We realize the smeared operators ∂t† and ∂t as creation and annihilation operators in F (H ) , respectively. Additional Q-commutation relations are obtained between the creation operators and between the annihilation operators. They are of the form ∂s†∂t†=Q (t ,s ) ∂t†∂s†, ∂s∂t=Q (t ,s ) ∂t∂s, valid for those s ,t ∈T for which |Q(s, t)| = 1.
Indigenous Representation and Alternative Schooling: Prioritising an Epistemology of Relationality
Keddie, Amanda
2014-01-01
This paper draws on a case study of a small alternative Indigenous school in Queensland, Australia. From the perspective of several of the school's Indigenous Elders, the paper foregrounds the significance of group differentiation at the school on the basis of Indigenous representation. However, it also considers how such…
Age-Related Changes in Children's Use of External Representations.
Zelazo, Philip David; Sommerville, Jessica A.; Nichols, Shana
1999-01-01
Three experiments explored 3- and 4-year olds' use of external representations. Results indicated that 4-year olds outperformed 3-year olds on self-recognition task; children performed better with photographs than drawings; a delay had no effect. Results suggested that assessments of self and other understanding may reflect children's ability to…
Unsettling Representational Practices: Inhabiting Relational Becomings in Early Childhood Education
Nxumalo, Fikile
2012-01-01
This article seeks to unsettle representational practices enacted through dominant multicultural pedagogical approaches in the early childhood classroom. Drawing from a research study in early childhood centers that investigated practitioners' and children's negotiations of racial difference, I explore how multicultural pedagogical approaches in…
Population coding and neural rhythmicity in the orbitofrontal cortex.
Pennartz, C.M.A.; van Wingerden, M.; Vinck, M.
2011-01-01
The orbitofrontal cortex has been implicated in the prediction of valuable outcomes based on environmental stimuli. However, it remains unknown how it represents outcome-predictive information at the population level, and how it provides temporal structure to such representations. Here, we pay atten
Representations of physical plausibility revealed by event-related potentials.
Roser, Matthew E; Fugelsang, Jonathan A; Handy, Todd C; Dunbar, Kevin N; Gazzaniga, Michael S
2009-08-05
Maintaining an accurate mental representation of the current environment is crucial to detecting change in that environment and ensuring behavioral coherence. Past experience with interactions between objects, such as collisions, has been shown to influence the perception of object interactions. To assess whether mental representations of object interactions derived from experience influence the maintenance of a mental model of the current stimulus environment, we presented physically plausible and implausible collision events while recording brain electrical activity. The parietal P300 response to 'oddball' events was found to be modulated by the physical plausibility of the stimuli, suggesting that past experience of object interactions can influence working memory processes involved in monitoring ongoing changes to the environment.
Knot invariants from Virasoro related representation and pretzel knots
Galakhov, D; Mironov, A; Morozov, A
2015-01-01
We remind the method to calculate colored Jones polynomials for the plat representations of knot diagrams from the knowledge of modular transformation (monodromies) of Virasoro conformal blocks with insertions of degenerate fields. As an illustration we use a rich family of pretzel knots, lying on a surface of arbitrary genus g, which was recently analyzed by the evolution method. Further generalizations can be to generic Virasoro modular transformations, provided by integral kernels, which can lead to the Hikami invariants.
A wavelet based neural model to optimize and read out a temporal population code
Andre eLuvizotto
2012-05-01
Full Text Available It has been proposed that the dense excitatory local connectivity of the neo-cortex plays a specific role in the transformation of spatial stimulus information into a temporal representation or a temporal population code (TPC. TPC provides for a rapid, robust and high-capacity encoding of salient stimulus features with respect to position, rotation and distortion. The TPC hypothesis gives a functional interpretation to a core feature of the cortical anatomy: its dense local and sparse long-range connectivity. Thus far, the question of how the TPC encoding can be decoded in downstream areas has not been addressed. Here, we present a neural circuit that decodes the spectral properties of the TPC using a biologically plausible implementation of a Haar transform. We perform a systematic investigation of our model in a recognition task using a standardized stimulus set. We consider alternative implementations using either regular spiking or bursting neurons and a range of spectral bands. Our results show that our wavelet readout circuit provides for robust decoding of the TPC and further compresses the code without loosing speed or quality of decoding. We show that in the TPC signal the relevant stimulus information is present in the frequencies around 100 Hz. Our results show that the TPC is constructed around a small number of coding components that can be well decoded by wavelet coefficients in a neuronal implementation. This solution to the TPC decoding problem suggests that cortical processing streams might well consist of sequential operations where spatio-temporal transformations at lower levels form a compact stimulus encoding using TPC that are are subsequently decoded back to a spatial representation using wavelet transforms. In addition, the results presented here shows that different properties of the stimulus might be transmitted to further processing stages using different frequency component that are captured by appropriately tuned
A toolbox for representational similarity analysis.
Hamed Nili
2014-04-01
Full Text Available Neuronal population codes are increasingly being investigated with multivariate pattern-information analyses. A key challenge is to use measured brain-activity patterns to test computational models of brain information processing. One approach to this problem is representational similarity analysis (RSA, which characterizes a representation in a brain or computational model by the distance matrix of the response patterns elicited by a set of stimuli. The representational distance matrix encapsulates what distinctions between stimuli are emphasized and what distinctions are de-emphasized in the representation. A model is tested by comparing the representational distance matrix it predicts to that of a measured brain region. RSA also enables us to compare representations between stages of processing within a given brain or model, between brain and behavioral data, and between individuals and species. Here, we introduce a Matlab toolbox for RSA. The toolbox supports an analysis approach that is simultaneously data- and hypothesis-driven. It is designed to help integrate a wide range of computational models into the analysis of multichannel brain-activity measurements as provided by modern functional imaging and neuronal recording techniques. Tools for visualization and inference enable the user to relate sets of models to sets of brain regions and to statistically test and compare the models using nonparametric inference methods. The toolbox supports searchlight-based RSA, to continuously map a measured brain volume in search of a neuronal population code with a specific geometry. Finally, we introduce the linear-discriminant t value as a measure of representational discriminability that bridges the gap between linear decoding analyses and RSA. In order to demonstrate the capabilities of the toolbox, we apply it to both simulated and real fMRI data. The key functions are equally applicable to other modalities of brain-activity measurement. The
Form factors and related quantities in clothed-particle representation
Shebeko Alexander
2017-01-01
Full Text Available We show new applications of the notion of clothed particles in quantum field theory. Its realization by means of the clothing procedure put forward by Greenberg and Schweber allows one to express the total Hamiltonian H and other generators of the Poincaré group for a given system of interacting fields through the creation (annihilation operators for the so-called clothed particles with physical (observed properties. Here such a clothed particle representation is used to calculate the matrix elements (shortly, form factors of the corresponding Nöther current operators sandwiched between the H eigenstates. Our calculations are performed with help of an iterative technique suggested by us earlier when constructing the NN → πNN transition operators. As an illustration, we outline some application of our approach in the spinor quantum electrodynamics.
Form factors and related quantities in clothed-particle representation
Shebeko, Alexander; Arslanaliev, Adam
2017-03-01
We show new applications of the notion of clothed particles in quantum field theory. Its realization by means of the clothing procedure put forward by Greenberg and Schweber allows one to express the total Hamiltonian H and other generators of the Poincaré group for a given system of interacting fields through the creation (annihilation) operators for the so-called clothed particles with physical (observed) properties. Here such a clothed particle representation is used to calculate the matrix elements (shortly, form factors) of the corresponding Nöther current operators sandwiched between the H eigenstates. Our calculations are performed with help of an iterative technique suggested by us earlier when constructing the NN → πNN transition operators. As an illustration, we outline some application of our approach in the spinor quantum electrodynamics.
Ahlqvist-Björkroth, Sari; Korja, Riikka; Junttila, Niina; Savonlahti, Elina; Pajulo, Marjukka; Räihä, Hannele; Aromaa, Minna
2016-07-01
Marital distress, parental depression, and weak quality of parental representations are all known risk factors for parent-child relationships. However, the relation between marital distress, depressive symptoms, and parents' prenatal representation is uncertain, especially regarding fathers. The present study aimed to explore how mothers' and fathers' prenatal experience of marital distress and depressive symptoms affects the organization of their prenatal representations in late pregnancy. Participants were 153 pregnant couples from a Finnish follow-up study called "Steps to the Healthy Development and Well-being of Children" (H. Lagström et al., ). Marital distress (Revised Dyadic Adjustment Scale; D.M. Busby, C. Christensen, D. Crane, & J. Larson, 1995) and depressive symptoms (Edinburgh Postnatal Depression Scale) were assessed at 20 gestational weeks, and prenatal representations (Working Model of the Child Interview; D. Benoit, K.C.H. Parker, & C.H. Zeanah, 1997; C.H. Zeanah, D. Benoit, M. Barton, & L. Hirshberg, 1996) were assessed between 29 and 32 gestational weeks. The mothers' risks of distorted representations increased significantly when they had at least minor depressive symptoms. Marital distress was associated with the fathers' prenatal representations, although the association was weak; fathers within the marital distress group had less balanced representations. Coexisting marital distress and depressive symptoms were only associated with the mothers' representations; lack of marital distress and depressive symptoms increased the likelihood for mothers to have balanced representations. The results imply that marital distress and depressive symptoms are differently related to the organizations of mothers' and fathers' prenatal representations. © 2016 Michigan Association for Infant Mental Health.
A simple model of optimal population coding for sensory systems.
Doi, Eizaburo; Lewicki, Michael S
2014-08-01
A fundamental task of a sensory system is to infer information about the environment. It has long been suggested that an important goal of the first stage of this process is to encode the raw sensory signal efficiently by reducing its redundancy in the neural representation. Some redundancy, however, would be expected because it can provide robustness to noise inherent in the system. Encoding the raw sensory signal itself is also problematic, because it contains distortion and noise. The optimal solution would be constrained further by limited biological resources. Here, we analyze a simple theoretical model that incorporates these key aspects of sensory coding, and apply it to conditions in the retina. The model specifies the optimal way to incorporate redundancy in a population of noisy neurons, while also optimally compensating for sensory distortion and noise. Importantly, it allows an arbitrary input-to-output cell ratio between sensory units (photoreceptors) and encoding units (retinal ganglion cells), providing predictions of retinal codes at different eccentricities. Compared to earlier models based on redundancy reduction, the proposed model conveys more information about the original signal. Interestingly, redundancy reduction can be near-optimal when the number of encoding units is limited, such as in the peripheral retina. We show that there exist multiple, equally-optimal solutions whose receptive field structure and organization vary significantly. Among these, the one which maximizes the spatial locality of the computation, but not the sparsity of either synaptic weights or neural responses, is consistent with known basic properties of retinal receptive fields. The model further predicts that receptive field structure changes less with light adaptation at higher input-to-output cell ratios, such as in the periphery.
Positive representations of general commutation relations allowing Wick ordering
Jorgensen, P E T; Werner, R F
1993-01-01
where the $T_{ij}^{k\\ell}$ are essentially arbitrary scalar coefficients. Examples comprise the $q$-canonical commutation relations introduced by Greenberg, Bozejko, and Speicher, and the twisted canonical (anti-)commutation relations studied by Pusz and Woronowicz, as well as the quantum group S$_\
Logical knowledge representation of regulatory relations in biomedical pathways
Zambach, Sine; Hansen, Jens Ulrik
2010-01-01
Knowledge on regulatory relations, in for example regulatory pathways in biology, is used widely in experiment design by biomedical researchers and in systems biology. The knowledge has typically either been represented through simple graphs or through very expressive differential equation...
Logical knowledge representation of regulatory relations in biomedical pathways
Zambach, Sine; Hansen, Jens Ulrik
2010-01-01
Knowledge on regulatory relations, in for example regulatory pathways in biology, is used widely in experiment design by biomedical researchers and in systems biology. The knowledge has typically either been represented through simple graphs or through very expressive differential equation...
The Impact of Merger Status and Relative Representation on Identification with a Merger Group
Filip Boen
2005-12-01
Full Text Available This experiment tested to what extent identification with a new merger group is determined by the status of that merger group and by the relative representation of the pre-merger ingroup. One hundred university students were assigned to a team of 'inductive' thinkers, and were later merged with a team of 'deductive' thinkers to form a team of 'analyst' thinkers. The status of the merger group (low, high and the relative representation of the ingroup into the novel merger group (low, high were manipulated. Participants identified more with the merger group in the high than in the low status condition, and they identified more in the high than in the low representation condition. The predicted interaction between relative representation and merger status was not significant. However, relative representation did interact with participants' pre-merger identification: Pre- and post-merger identification were positively related when the ingroup was highly represented, but 'negatively' when the ingroup was lowly represented.
Hannah, Samuel D; Shedden, Judith M; Brooks, Lee R; Grundy, John G
2016-11-01
In this paper, we use behavioural methods and event-related potentials (ERPs) to explore the relations between informational and instantiated features, as well as the relation between feature abstraction and rule type. Participants are trained to categorize two species of fictitious animals and then identify perceptually novel exemplars. Critically, two groups are given a perfectly predictive counting rule that, according to Hannah and Brooks (2009. Featuring familiarity: How a familiar feature instantiation influences categorization. Canadian Journal of Experimental Psychology/Revue Canadienne de Psychologie Expérimentale, 63, 263-275. Retrieved from http://doi.org/10.1037/a0017919), should orient them to using abstract informational features when categorizing the novel transfer items. A third group is taught a feature list rule, which should orient them to using detailed instantiated features. One counting-rule group were taught their rule before any exposure to the actual stimuli, and the other immediately after training, having learned the instantiations first. The feature-list group were also taught their rule after training. The ERP results suggest that at test, the two counting-rule groups processed items differently, despite their identical rule. This not only supports the distinction that informational and instantiated features are qualitatively different feature representations, but also implies that rules can readily operate over concrete inputs, in contradiction to traditional approaches that assume that rules necessarily act on abstract inputs.
Fuzzy Relational Databases: Representational Issues and Reduction Using Similarity Measures.
Prade, Henri; Testemale, Claudette
1987-01-01
Compares and expands upon two approaches to dealing with fuzzy relational databases. The proposed similarity measure is based on a fuzzy Hausdorff distance and estimates the mismatch between two possibility distributions using a reduction process. The consequences of the reduction process on query evaluation are studied. (Author/EM)
The representation of manipulable solid objects in a relational database
Bahler, D.
1984-01-01
This project is concerned with the interface between database management and solid geometric modeling. The desirability of integrating computer-aided design, manufacture, testing, and management into a coherent system is by now well recognized. One proposed configuration for such a system uses a relational database management system as the central focus; the various other functions are linked through their use of a common data repesentation in the data manager, rather than communicating pairwise to integrate a geometric modeling capability with a generic relational data managemet system in such a way that well-formed questions can be posed and answered about the performance of the system as a whole. One necessary feature of any such system is simplification for purposes of anaysis; this and system performance considerations meant that a paramount goal therefore was that of unity and simplicity of the data structures used.
Relating Weight Constraint and Aggregate Programs: Semantics and Representation
Liu, Guohua
2011-01-01
Weight constraint and aggregate programs are among the most widely used logic programs with constraints. In this paper, we relate the semantics of these two classes of programs, namely the stable model semantics for weight constraint programs and the answer set semantics based on conditional satisfaction for aggregate programs. Both classes of programs are instances of logic programs with constraints, and in particular, the answer set semantics for aggregate programs can be applied to weight constraint programs. We show that the two semantics are closely related. First, we show that for a broad class of weight constraint programs, called strongly satisfiable programs, the two semantics coincide. When they disagree, a stable model admitted by the stable model semantics may be circularly justified. We show that the gap between the two semantics can be closed by transforming a weight constraint program to a strongly satisfiable one, so that no circular models may be generated under the current implementation of ...
PRINCIPLES OF REPRESENTATING THE DICTIONARY OF INVESTOR RELATIONS TERMS
Sarangova Tatiana Apolinarievna
2013-05-01
Full Text Available This article treats the problems of identification of principles of representing the vocabulary of banking terms in the field Investor Relations. The main methods of the research are literary analysis and the statistic method. The research defines term and specifics “Investor Relations”, provides a clear demarcation of terms terminography and lexicography, describes the principles of representing the vocabulary of IR terms. Results of the research can be used by IR managers, employees of finance and investment companies and banks, interpreters, teachers, postgraduates and students of economy faculties in different courses of teaching.
Pasi Nieminen,
2012-05-01
Full Text Available Previous physics education research has raised the question of “hidden variables” behind students’ success in learning certain concepts. In the context of the force concept, it has been suggested that students’ reasoning ability is one such variable. Strong positive correlations between students’ preinstruction scores for reasoning ability (measured by Lawson’s Classroom Test of Scientific Reasoning and their learning of forces [measured by the Force Concept Inventory (FCI] have been reported in high school and university introductory courses. However, there is no published research concerning the relation between students’ ability to interpret multiple representations consistently (i.e., representational consistency and their learning of forces. To investigate this, we collected 131 high school students’ pre- and post-test data of the Representational Variant of the Force Concept Inventory (for representational consistency and the FCI. The students’ Lawson pretest data were also collected. We found that the preinstruction level of students’ representational consistency correlated strongly with student learning gain of forces. The correlation (0.51 was almost equal to the correlation between Lawson prescore and learning gain of forces (0.52. Our results support earlier findings which suggest that scientific reasoning ability is a hidden variable behind the learning of forces. In addition, we suggest that students’ representational consistency may also be such a factor, and that this should be recognized in physics teaching.
Attachment representations in adulthood: relations with parental behaviors.
Koren-Karie, N
2000-01-01
The paper presents two standardized measurements of attachment. The Strange Situation Procedure is an observational measure of the reaction of 12-18-month-old infants to their parent after being exposed to brief separations from him/her. Four main types of responses are noted, and have been noted in a range of cultures. The second measure is the Adult Attachment Interview which is a semi-structured interview of 18 questions that discusses childhood memories and assesses the current state of mind with regard to attachment issues. Four types of characteristic response styles have been noted in a range of cultures, and this measure seems to be related to certain types of parenting. Studies of the link between the two measures have been complicated, as the adult measure does not include the capacity to be available for the child. A further instrument, the Maternal Empathic Understanding Procedure, designed to assess parent's ability to see things from the child's point of view, is suggested as a possible mediator between parental attachment style and parenting behavior. These studies permit standardized evaluation of parenting skills, facilitate the study of intergenerational transmission of these skills, and suggest the possibility of psychotherapeutic interventions that focus on these areas.
Learning connective-based word representations for implicit discourse relation identification
Braud, Chloé Elodie; Denis, Pascal
2016-01-01
We introduce a simple semi-supervised ap-proach to improve implicit discourse relation identification. This approach harnesses large amounts of automatically extracted discourse connectives along with their arguments to con-struct new distributional word representations. Specifically, we represent...... words in the space of discourse connectives as a way to directly encode their rhetorical function. Experiments on the Penn Discourse Treebank demonstrate the effectiveness of these task-tailored repre-sentations in predicting implicit discourse re-lations. Our results indeed show that, despite...... their simplicity, these connective-based rep-resentations outperform various off-the-shelf word embeddings, and achieve state-of-the-art performance on this problem....
Elia, Iliada; Panaoura, Areti; Eracleous, Anastasia; Gagatsis, Athanasios
2007-01-01
The present study explores pupils' constructed definitions of the concept of function in relation to their abilities in dealing with tasks of functions involving different forms of representations and problem solving tasks. A major concern is also to examine the interrelations between these three ways of thinking about or dealing with the concept…
Huang, Rongjin; Cai, Jinfa
2011-01-01
This study investigates Chinese and U.S. teachers' construction and use of pedagogical representations surrounding implementation of mathematical tasks. It does this by analyzing video-taped lessons from the Learner's Perspective Study, involving 15 Chinese and 10 U.S. consecutive lessons on the topic of linear equations/linear relations. We…
Elia, Iliada; Panaoura, Areti; Eracleous, Anastasia; Gagatsis, Athanasios
2007-01-01
The present study explores pupils' constructed definitions of the concept of function in relation to their abilities in dealing with tasks of functions involving different forms of representations and problem solving tasks. A major concern is also to examine the interrelations between these three ways of thinking about or dealing with the concept…
Campbell, John M
2011-01-01
We present an integral representation of Kekul\\'{e} numbers for $P_{2} (n)$ benzenoids. Related integrals of the form $\\int_{-\\pi}^{\\pi} \\frac{\\cos(nx)}{\\sin^{2}x +k} dx$ are evaluated. Conjectures relating double integrals of the form $\\int_{0}^{m} \\int_{-\\pi}^{\\pi} \\frac{\\cos (2nx)}{k+\\sin^{2}x} dx dk $ to Smarandache sequences are presented.
Murray, Lynne; Pella, Jeff E; De Pascalis, Leonardo; Arteche, Adriane; Pass, Laura; Percy, Ray; Creswell, Catharine; Cooper, Peter J
2014-11-01
Anxious mothers' parenting, particularly transfer of threat information, has been considered important in their children's risk for social anxiety disorder (SAnxD), and maternal narratives concerning potential social threat could elucidate this contribution. Maternal narratives to their preschool 4- to 5-year-old children, via a picture book about starting school, were assessed in socially anxious (N = 73), and nonanxious (N = 63) mothers. Child representations of school were assessed via doll play (DP). After one school term, mothers (Child Behavior Checklist [CBCL]) and teachers (Teacher Report Form) reported on child internalizing problems, and child SAnxD was assessed via maternal interview. Relations between these variables, infant behavioral inhibition, and attachment, were examined. Socially anxious mothers showed more negative (higher threat attribution) and less supportive (lower encouragement) narratives than controls, and their children's DP representations SAnxD and CBCL scores were more adverse. High narrative threat predicted child SAnxD; lower encouragement predicted negative child CBCL scores and, particularly for behaviorally inhibited children, Teacher Report Form scores and DP representations. In securely attached children, CBCL scores and risk for SAnxD were affected by maternal anxiety and threat attributions, respectively. Low encouragement mediated the effects of maternal anxiety on child DP representations and CBCL scores. Maternal narratives are affected by social anxiety and contribute to adverse child outcome.
Sarantakis, Nicholas
2014-01-01
The current literature review offers a critical evaluation of the extent to which our native language determines the ways in which we conceptualise the external world. Experimental studies regarding colour perception, spatial cognition and spatial representation of events in time are examined. It is argued that the available evidence supports the hypothesis of (a flexible) linguistic relativity, instead of the linguistic determinism hypothesis. Moreover, it is suggested that the impact of lan...
Friedman, Alinda; Montello, Daniel R
2006-03-01
The authors examined whether absolute and relative judgments about global-scale locations and distances were generated from common representations. At the end of a 10-week class on the regional geography of the United States, participants estimated the latitudes of 16 North American cities and all possible pairwise distances between them. Although participants were relative experts, their latitude estimates revealed the presence of psychologically based regions with large gaps between them and a tendency to stretch North America southward toward the equator. The distance estimates revealed the same properties in the representation recovered via multidimensional scaling. Though the aggregated within- and between-regions distance estimates were fitted by Stevens's law (S. S. Stevens, 1957), this was an averaging artifact: The appropriateness of a power function to describe distance estimates depended on the regional membership of the cities. The authors conclude that plausible reasoning strategies, combined with regionalized representations and beliefs about the location of these relative to global landmarks, underlie global-scale latitude and distance judgments.
Bale, Michael R; Ince, Robin A A; Santagata, Greta; Petersen, Rasmus S
2015-01-01
The rodent whisker-associated thalamic nucleus (VPM) contains a somatotopic map where whisker representation is divided into distinct neuronal sub-populations, called "barreloids". Each barreloid projects to its associated cortical barrel column and so forms a gateway for incoming sensory stimuli to the barrel cortex. We aimed to determine how the population of neurons within one barreloid encodes naturalistic whisker motion. In rats, we recorded the extracellular activity of up to nine single neurons within a single barreloid, by implanting silicon probes parallel to the longitudinal axis of the barreloids. We found that play-back of texture-induced whisker motion evoked sparse responses, timed with millisecond precision. At the population level, there was synchronous activity: however, different subsets of neurons were synchronously active at different times. Mutual information between population responses and whisker motion increased near linearly with population size. When normalized to factor out firing rate differences, we found that texture was encoded with greater informational-efficiency than white noise. These results indicate that, within each VPM barreloid, there is a rich and efficient population code for naturalistic whisker motion based on precisely timed, population spike patterns.
Uncertainties related to the representation of momentum transport in shallow convection
Schlemmer, Linda; Bechtold, Peter; Sandu, Irina; Ahlgrimm, Maike
2017-04-01
The vertical transport of horizontal momentum by convection has an important impact on the general circulation of the atmosphere as well as on the life cycle and track of cyclones. So far convective momentum transport (CMT) has mostly been studied for deep convection, whereas little is known about its characteristics and importance in shallow convection. In this study CMT by shallow convection is investigated by analyzing both data from large-eddy simulations (LES) and simulations performed with the Integrated Forecasting System (IFS) of the European Centre for Medium-Range Weather Forecasts (ECMWF). In addition, the central terms underlying the bulk mass-flux parametrization of CMT are evaluated offline. Further, the uncertainties related to the representation of CMT are explored by running the stochastically perturbed parametrizations (SPP) approach of the IFS. The analyzed cases exhibit shallow convective clouds developing within considerable low-level wind shear. Analysis of the momentum fluxes in the LES data reveals significant momentum transport by the convection in both cases, which is directed down-gradient despite substantial organization of the cloud field. A detailed inspection of the convection parametrization reveals a very good representation of the entrainment and detrainment rates and an appropriate representation of the convective mass and momentum fluxes. To determine the correct values of mass-flux and in-cloud momentum at the cloud base in the parametrization yet remains challenging. The spread in convection-related quantities generated by the SPP is reasonable and addresses many of the identified uncertainties.
Andrews, Sally; Burton, A Mike; Schweinberger, Stefan R; Wiese, Holger
2017-08-01
Natural variability between instances of unfamiliar faces can make it difficult to reconcile two images as the same person. Yet for familiar faces, effortless recognition occurs even with considerable variability between images. To explore how stable face representations develop, we employed incidental learning in the form of a face sorting task. In each trial, multiple images of two facial identities were sorted into two corresponding piles. Following the sort, participants showed evidence of having learnt the faces performing more accurately on a matching task with seen than with unseen identities. Furthermore, ventral temporal event-related potentials were more negative in the N250 time range for previously seen than for previously unseen identities. These effects appear to demonstrate some degree of abstraction, rather than simple picture learning, as the neurophysiological and behavioural effects were observed with novel images of the previously seen identities. The results provide evidence of the development of facial representations, allowing a window onto natural mechanisms of face learning.
Note on recursion relations for the $\\mathcal{Q}$-cut representation
Feng, Bo; Huang, Rijun; Luo, Ming-xing
2016-01-01
In this note, we study the $\\mathcal{Q}$-cut representation by combining it with BCFW deformation. As a consequence, the one-loop integrand is expressed in terms of a recursion relation, i.e., $n$-point one-loop integrand is constructed using tree-level amplitudes and $m$-point one-loop integrands with $m\\leq n-1$. By giving explicit examples, we show that the integrand from the recursion relation is equivalent to that from Feynman diagrams or the original $\\mathcal{Q}$-cut construction, up to scale free terms.
Nicholas P. Sarantakis
2014-10-01
Full Text Available The current literature review offers a critical evaluation of the extent to which our native language determines the ways in which we conceptualise the external world. Experimental studies regarding colour perception, spatial cognition and spatial representation of events in time are examined. It is argued that the available evidence supports the hypothesis of (a flexible linguistic relativity, instead of the linguistic determinism hypothesis. Moreover, it is suggested that the impact of language on thought is mediated by three pathways: (i the intention of an individual to express their thoughts; (ii the environmental and cultural context; and (iii the ability of an individual to learn different modes of reasoning.
Homogenous Chaotic Network Serving as a Rate/Population Code to Temporal Code Converter
Mikhail V. Kiselev
2014-01-01
Full Text Available At present, it is obvious that different sections of nervous system utilize different methods for information coding. Primary afferent signals in most cases are represented in form of spike trains using a combination of rate coding and population coding while there are clear evidences that temporal coding is used in various regions of cortex. In the present paper, it is shown that conversion between these two coding schemes can be performed under certain conditions by a homogenous chaotic neural network. Interestingly, this effect can be achieved without network training and synaptic plasticity.
Making sense of HIV stigma: Representations in young Africans' HIV-related narratives.
Winskell, Kate; Holmes, Kathleen; Neri, Elizabeth; Berkowitz, Rachel; Mbakwem, Benjamin; Obyerodhyambo, Oby
2015-01-01
In addition to undermining the quality of life of those infected and affected by HIV, HIV-related stigma impedes access to prevention and treatment services, thereby threatening to erode the promise of recent advances in these areas. This paper provides insights into the socio-contextual and sense-making processes that inform HIV stigma through an innovative form of empirical data: creative fictional narratives written by young Africans (aged 10-24) for an HIV-themed scriptwriting competition. From a sample of 586 narratives from six sub-Saharan countries, we selected for illustrative purposes three on account of the complexity of their representation of HIV stigma. We conducted a close reading of each, using stigma theory as a lens. Through their explicit accounts of stigmatising attitudes and behaviours of characters and through implicit contradictions, tensions and ambivalence in their messaging, the narratives provide insights into the symbolic and social processes that create and sustain HIV stigma. Our analysis illuminates the authors' struggles to navigate the cultural resources available to them in their efforts to make sense of HIV, gender and sexuality. It highlights some limitations of current communication efforts and the potential for narrative-based communication approaches to engage with representations that devalue women and people living with HIV.
Career representations in high school pupils and students in relation to gender characteristics
A.M. Sheveleva
2013-07-01
Full Text Available We describe a study of career representations in school and university students in relation to gender characteristics. The sample consisted of 36 students of XI grade and 40 students of I year of high school. We tested the hypothesis about relationship of career representations with gen-der characteristics of the subjects and their stage of professional development. The methods we used were “career anchors” by E. Schein, “Psychological gender” by S. Bem, survey “Professional career ideals" by A.M. Sheveleva. The statistical significance level of results was 0.05. It was re-vealed that, despite both school pupils and students preferred achievements, wealth and social recognition as the content of the ideal career, there are differences between the samples. Pupils are more focused on the “General managerial competence” and “Security/stability”, the students –on “Service/dedication to a cause” and “Technical/functional competence”. Regardless of sex, school pupils with an increase of masculinity have enhanced value of ”Pure challenge” orienta-tion and lowered value of the “Mode of Life” ideal career. The female students with increased femininity have higher importance of such content ideal career as “Experience Acquisition” and “Professional Path”, the value of career orientation “Autonomy/independence” is increased.
Representations of race relations in the classroom: the black in the everyday school life
Wilma de Nazaré Baía Coelho
2015-11-01
Full Text Available This paper presents some preliminaries results of a research that investigates the representations about race, color, Difference, Prejudgment and Racial Discrimination of the school’s agents teachers, employees and students on the quotidian of the History’s, Portuguese’s and Art’s classes of the first two year of the secondary education of a Belém-PA’s private school, in order to understand the place of the black people in the school pedagogic practices, regarding the obligation of touching racial subjects as established by the low 10.639/2003. Using the methodological and theoretic approach of Pierre Bourdieu and Roger Chartier, we analyzed the representations obtained by the non-participative observation in those classes. We realized that teachers almost didn’t know anything about the low 10.639/2003 and about the ethnic and racial question on Brazil, what brings as result the reproduction of racial prejudgment and discrimination by the students. Our analysis aims, from understanding the problems with teacher development, to understand the problems related to the ethnic and racial question at school and propose solutions.
On a time-domain representation of the Kramers-Kronig dispersion relations
Waters; Hughes; Brandenburger; Miller
2000-11-01
The development of Kramers-Kronig dispersion relations is typically carried out in the frequency domain. An alternative approach known as the time-causal theory develops dispersion relations for media with attenuation obeying a frequency power law through analysis in the time domain [T. L. Szabo, J. Acoust. Soc. Am. 96, 491-500 (1994)]. Although both approaches predict identical dispersion relations, it is perceived that these two approaches are distinct from each other. It is shown, however, that the time-causal theory is in essence a time-domain formulation of the Kramers-Kronig dispersion relations for the special case of media with attenuation obeying a frequency power law. Additionally, it is shown that time-domain representations of the Kramers-Kronig dispersion relations are available for a broader class of media than simply those with power law attenuation. The time-causal theory and the Kramers-Kronig dispersion relations can be viewed as two complementary, yet equivalent, approaches to the study of dispersion.
Continuous spatial representations in the olfactory bulb may reflect perceptual categories
Benjamin eAuffarth
2011-10-01
Full Text Available In sensory processing of odors, the olfactory bulb is an important relay station, where odor representations are noise-filtered, sharpened, and possibly re-organized. An organization by perceptual qualities has been found previously in the piriform cortex, however several recent studies indicate that the olfactory bulb code reflects behaviorally relevant dimensions spatially as well as at the population level. We apply a statistical analysis on 2-deoxyglucose images, taken over the entire bulb of glomerular layer of the rat, in order to see how the recognition of odors in the nose is translated into a map of odor quality in the brain. We first confirm previous studies that the first principal component could be related to pleasantness, however the next higher principal components are not directly clear. We then find mostly continuous spatial representations for perceptual categories. We compare the space spanned by spatial and population codes to human reports of perceptual similarity between odors and our results suggest that perceptual categories could be already embedded in glomerular activations and that spatial representations give a better match than population codes. This suggests that human and rat perceptual dimensions of odorant coding are related and indicates that perceptual qualities could be represented as continuous spatial codes of the olfactory bulb glomerulus population.
Light-front representation of chiral dynamics with Delta isobar and large-N_c relations
Granados, C
2016-01-01
Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O(M_pi^{-1}) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). Recent work has shown that the EFT results can be represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition of the nucleon to soft-pion-nucleon intermediate states, resulting in a quantum-mechanical picture of the peripheral transverse densities. We now extend this representation to include intermediate states with Delta isobars and implement relations based on the large-N_c limit of QCD. We derive the wave function overlap formulas for the Delta contributions to the peripheral transverse densities by way of a three-dimensional reduction of relativistic chiral EFT expressions. Our procedure effectively maintains rotational invariance and avoids the ambiguit...
Yves Roquelaure
2016-06-01
Full Text Available Effective and sustainable prevention of work-related musculoskeletal disorders (WR-MSDs remains a challenge for preventers and policy makers. Coordination of stakeholders involved in the prevention of WR-MSDs is a key factor that requires greater reflection on common knowledge and shared representation of workers' activities among stakeholders. Information on workers' strategies and operational leeway should be the core of common representations, because it places workers at the center of the “work situation system” considered by the intervention models. Participatory ergonomics permitting debates among stakeholders about workers' activity and strategies to cope with the work constraints in practice could help them to share representations of the “work situation system” and cooperate. Sharing representation therefore represents a useful tool for prevention, and preventers should provide sufficient space and time for dialogue and discussion of workers' activities among stakeholders during the conception, implementation, and management of integrated prevention programs.
Learning to repair plans and schedules using a relational (deictic representation
J. Palombarini
2010-09-01
Full Text Available Unplanned and abnormal events may have a significant impact on the feasibility of plans and schedules which requires to repair them 'on-the-fly' to guarantee due date compliance of orders-in-progress and negotiating delivery conditions for new orders. In this work, a repair-based rescheduling approach based on the integration of intensive simulations with logical and relational reinforcement learning is proposed. Based on a relational (deictic representation of schedule states, a number of repair operators have been designed to guide the search towards a goal state. The knowledge generated via simulation is encoded in a relational regression tree for the Q-value function defining the utility of applying a given repair operator at a given schedule state. A prototype implementation in Prolog language is discussed using a representative example of three batch extruders processing orders for four different products. The learning curve for the problem of inserting a new order vividly illustrates the advantages of logical and relational learning in rescheduling.
Ronald van den Berg
2010-01-01
Full Text Available An object in the peripheral visual field is more difficult to recognize when surrounded by other objects. This phenomenon is called "crowding". Crowding places a fundamental constraint on human vision that limits performance on numerous tasks. It has been suggested that crowding results from spatial feature integration necessary for object recognition. However, in the absence of convincing models, this theory has remained controversial. Here, we present a quantitative and physiologically plausible model for spatial integration of orientation signals, based on the principles of population coding. Using simulations, we demonstrate that this model coherently accounts for fundamental properties of crowding, including critical spacing, "compulsory averaging", and a foveal-peripheral anisotropy. Moreover, we show that the model predicts increased responses to correlated visual stimuli. Altogether, these results suggest that crowding has little immediate bearing on object recognition but is a by-product of a general, elementary integration mechanism in early vision aimed at improving signal quality.
van den Berg, Ronald; Roerdink, Jos B T M; Cornelissen, Frans W
2010-01-22
An object in the peripheral visual field is more difficult to recognize when surrounded by other objects. This phenomenon is called "crowding". Crowding places a fundamental constraint on human vision that limits performance on numerous tasks. It has been suggested that crowding results from spatial feature integration necessary for object recognition. However, in the absence of convincing models, this theory has remained controversial. Here, we present a quantitative and physiologically plausible model for spatial integration of orientation signals, based on the principles of population coding. Using simulations, we demonstrate that this model coherently accounts for fundamental properties of crowding, including critical spacing, "compulsory averaging", and a foveal-peripheral anisotropy. Moreover, we show that the model predicts increased responses to correlated visual stimuli. Altogether, these results suggest that crowding has little immediate bearing on object recognition but is a by-product of a general, elementary integration mechanism in early vision aimed at improving signal quality.
Energy-efficient population coding constrains network size of a neuronal array system
Yu, Lianchun; Zhang, Chi; Liu, Liwei; Yu, Yuguo
2016-01-01
We consider the open issue of how the energy efficiency of the neural information transmission process, in a general neuronal array, constrains the network size, and how well this network size ensures the reliable transmission of neural information in a noisy environment. By direct mathematical analysis, we have obtained general solutions proving that there exists an optimal number of neurons in the network, where the average coding energy cost (defined as energy consumption divided by mutual information) per neuron passes through a global minimum for both subthreshold and superthreshold signals. With increases in background noise intensity, the optimal neuronal number decreases for subthreshold signals and increases for suprathreshold signals. The existence of an optimal number of neurons in an array network reveals a general rule for population coding that states that the neuronal number should be large enough to ensure reliable information transmission that is robust to the noisy environment but small enough to minimize energy cost.
Sex-contingent face after-effects suggest distinct neural populations code male and female faces.
Little, Anthony C; DeBruine, Lisa M; Jones, Benedict C
2005-11-01
Exposure to faces biases perceptions of subsequently viewed faces. Faces similar to those seen previously are judged more normal and attractive than they were prior to exposure. Here we show sex-contingent after-effects following adaptation to eye-spacing (experiment 1), facial identity (experiment 2) and masculinity (experiment 3). Viewing faces of one sex with increased eye-spacing and faces of the other sex with decreased eye-spacing simultaneously induced opposite after-effects for male and female faces (assessed by normality judgments). Viewing faces transformed in identity or masculinity increased preferences for novel faces with characteristics similar to those viewed only when the sex of the faces presented in the adaptation phase and in post-adaptation preference tests were congruent. Because after-effects reflect changes in responses of neural populations that code faces, our findings indicate that distinct neural populations code male and female faces.
Direction-Selective Circuits Shape Noise to Ensure a Precise Population Code.
Zylberberg, Joel; Cafaro, Jon; Turner, Maxwell H; Shea-Brown, Eric; Rieke, Fred
2016-01-20
Neural responses are noisy, and circuit structure can correlate this noise across neurons. Theoretical studies show that noise correlations can have diverse effects on population coding, but these studies rarely explore stimulus dependence of noise correlations. Here, we show that noise correlations in responses of ON-OFF direction-selective retinal ganglion cells are strongly stimulus dependent, and we uncover the circuit mechanisms producing this stimulus dependence. A population model based on these mechanistic studies shows that stimulus-dependent noise correlations improve the encoding of motion direction 2-fold compared to independent noise. This work demonstrates a mechanism by which a neural circuit effectively shapes its signal and noise in concert, minimizing corruption of signal by noise. Finally, we generalize our findings beyond direction coding in the retina and show that stimulus-dependent correlations will generally enhance information coding in populations of diversely tuned neurons.
Relations Between Characteristic Function, Positive P-Representation and Coherent Thermal State
FAN Hong-Yi; XU Xing-Lei
2007-01-01
We employ the coherent thermal states (a kind of entangled states) in thermal field dynamics to establish a complete entangled state formalism expressing pseudo-classical representations of density operator for light field.Especially, the relationship between the coherent thermal state and the characteristic function and the positive P representation in quantum optics theory are obtained.
Representation of spatial relations in the language and fiction text: linguacultural aspect
Aketina Olga Sergeevna
2016-06-01
Full Text Available The article deals with the representation of the physical space in the semantic space of language and literary text. It was found that the threedimensionality of the perceived space allows to describe metrically and topologically. Ontological essence of space is manifested in translation its properties through objects, given in feelings. Spatial objects are characterized by a set of properties that secure their borders and sizes. Spatial concepts are formed as a result of receptive activities, special importance in this process are the signs of dimensional compatibility, mobility and immobility, the relationship to the norm, etc. Cognitive mechanisms that form the basis of perception of the world are reflected in a consistent verbalization of threedimensional space. The importance of specific measurements and hierarchical subordination is not due to the presence of the subject-spatial relations, and foreshortening of human perception of spatial relationships and space category as a whole. The formation of «space» concept in the linguistic and artistic pictures of the world is considered. It is noted that the category of space is a collection of several closely related concepts that represent mental space images, position, distance, etc.
[Nurses' social representations of work-related stress in an emergency room].
Oliveira, Joana D'Arc de Souza; Achieri, João Carlos; Pessoa Júnior, João Mário; de Miranda, Francisco Arnoldo Nunes; Almeida, Maria das Graças
2013-08-01
The aim of this study was to understand the social representations of nurses in the emergency room and their relationship to stress. This descriptive, exploratory study was performed using a qualitative approach, with Social Representations Theory being the prime focus. Research was conducted at a benchmark public hospital for emergency services in the municipality of Natal/RN. The sample consisted of 10 nurses. A content analysis approach was used for data analysis. The results indicate that the relationship between nurses' social representations of work and stress is a complex and multi-faceted phenomenon that contributes to the development of physical, emotional and mental illnesses, and exhaustion.
Murray, J. P.
1982-08-01
Terrain is widely recognized as a critical influence on VHF and UHF radio signal strengths, and hence on radio communications range. The same terrain influences have major effects on other aspects of tactical operations, particularly mobility of the tactical units. Both classes of influence are considered in various ways in simulating tactical operations. Planners are faced with a conflict between the need to represent physical circumstances as accurately as possible and constraints on the resources available to the planning process. Resources of principal concern are the funds available to develop adequate representations of terrain and their mathematical analogs, and the computational power and time required to apply them during the course of planning simulations. In many cases, the need to evaluate many signal paths in each of many scenarios produces a computation-intensive process that forces approximations that are substantially cruder than the current state of the propagation prediction art could use to advantage. This paper describes several approaches to terrain treatment, summarizes their relative costs and benefits, and compares the benefits achieved in each case with the fidelity produced by comparable terrain considerations in mobility estimates. The effect on the interpretation of simulation results for both discrete and general studies is also discussed.
Lachmair, Martin; Dudschig, Carolin; de la Vega, Irmgard; Kaup, Barbara
2014-05-01
Numerical processing and language processing are both grounded in space. In the present study we investigated whether these are fully independent phenomena, or whether they share a common basis. If number processing activates spatial dimensions that are also relevant for understanding words, then we can expect that processing numbers may influence subsequent lexical access to words. Specifically, if high numbers relate to upper space, then they can be expected to facilitate understanding of words such as bird that are having referents typically found in the upper vertical space. The opposite should hold for low numbers. These should facilitate the understanding of words such as ground referring to entities with referents in the lower vertical space. Indeed, in two experiments we found evidence for such an interaction between number and word processing. By eliminating a contribution of linguistic factors gained from additional investigations on large text corpora, this strongly suggests that understanding numbers and language is based on similar modal representations in the brain. The implications of these findings for a broader perspective on grounded cognition will be discussed.
Bosnjak, Gary
2016-01-01
In this paper we construct a new factorized representation of the $R$-matrix related to the affine algebra $U_{q}(\\widehat{sl_{n}})$ for symmetric tensor representations with arbitrary weights. Using the 3D approach we obtain explicit formulas for the matrix elements of the $R$-matrix and give a simple proof that a "twisted" $R$-matrix is stochastic. We also discuss symmetries of the $R$-matrix, its degenerations and compare our formulas with other results available in the literature.
Rezende, Raphael Batista de; Moreira, Marcelo Rasga
2016-05-01
This article analyzes the influence of "Representative Configuration" of the Rio de Janeiro Municipal Health Council (CMS) on user counselor performance. Representative Configuration is defined as being a combination of two institutional rule axes: Axis 1 consists of eligibility and involvement rules, and Axis 2, of representation rules. The theoretical discussion was centered on the relationship between Representation and Involvement in its contemporary democratic context, and specifically relates to the Municipal Health Council (CMS). The study method focused on Participative Observation, Interviews, and Document Analysis. The results show that the district counsel representatives act based on the mandate of those they represent, since they create close ties with these institutions, whereas municipal counselors are more likely to lean towards autonomy in their representation, resulting in weaker ties with these bodies. The representatives' mandate-based posture is combined with a more in-depth involvement in meetings and greater expression of their represented citizens' interests.
A stochastic model of chromatin modification: cell population coding of winter memory in plants.
Satake, Akiko; Iwasa, Yoh
2012-06-07
Biological memory, a sustained cellular response to a transient stimulus, has been found in many natural systems. The best example in plants is the winter memory by which plants can flower in favorable conditions in spring. For this winter memory, epigenetic regulation of FLOWERING LOCUS C (FLC), which acts as a floral repressor, plays a key role. Exposure to prolonged periods of cold results in the gradual suppression of FLC, which allows plants to measure the length of cold and to flower only after a sufficiently long winter. Although many genes involved in histone modifications have been isolated, molecular mechanisms of winter memory are not well understood. Here, we develop a model for chromatin modification, in which the dynamics of a single nucleosome are aggregated to on/off behavior of FLC expression at the cellular level and further integrated to a change of FLC expression at the whole-plant level. We propose cell-population coding of winter memory: each cell is described as a bistable system that shows heterogeneous timing of the transition from on to off in FLC expression under cold and measures the length of cold as the proportion of cells in the off state. This mechanism well explains robust FLC regulation and stable inheritance of winter memory after cell division in response to noisy signals. Winter memory lasts longer if deposition of the repressive histone mark occurs faster. A difference in deposition speed would discriminate between stable maintenance of FLC repression in annuals and transient expression in perennials.
Francesco P Battaglia
2011-08-01
Full Text Available After acquisition, memories underlie a process of consolidation, making them more resistant to interference and brain injury. Memory consolidation involves systems-level interactions, most importantly between the hippocampus and associated structures, which takes part in the initial encoding of memory, and the neocortex, which supports long-term storage. This dichotomy parallels the contrast between episodic memory (tied to the hippocampal formation, collecting an autobiographical stream of experiences, and semantic memory, a repertoire of facts and statistical regularities about the world, involving the neocortex at large. Experimental evidence points to a gradual transformation of memories, following encoding, from an episodic to a semantic character. This may require an exchange of information between different memory modules during inactive periods. We propose a theory for such interactions and for the formation of semantic memory, in which episodic memory is encoded as relational data. Semantic memory is modeled as a modified stochastic grammar, which learns to parse episodic configurations expressed as an association matrix. The grammar produces tree-like representations of episodes, describing the relationships between its main constituents at multiple levels of categorization, based on its current knowledge of world regularities. These regularities are learned by the grammar from episodic memory information, through an expectation-maximization procedure, analogous to the inside-outside algorithm for stochastic context-free grammars. We propose that a Monte-Carlo sampling version of this algorithm can be mapped on the dynamics of ``sleep replay'' of previously acquired information in the hippocampus and neocortex. We propose that the model can reproduce several properties of semantic memory such as decontextualization, top-down processing, and creation of schemata.
Light-front representation of chiral dynamics with Δ isobar and large- N c relations
Granados, C.; Weiss, C.
2016-06-01
Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O( M π - 1 ) the densities are governed by chiral dynamics and can be calculated model-independently using chiral effective field theory (EFT). Recent work has shown that the EFT results can be represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition of the nucleon to soft-pion-nucleon intermediate states, resulting in a quantum-mechanical picture of the peripheral transverse densities. We now extend this representation to include intermediate states with Δ isobars and implement relations based on the large- N c limit of QCD. We derive the wave function overlap formulas for the Δ contributions to the peripheral transverse densities by way of a three-dimensional reduction of relativistic chiral EFT expressions. Our procedure effectively maintains rotational invariance and avoids the ambiguities with higher-spin particles in the light-front time-ordered approach. We study the interplay of π N and πΔ intermediate states in the quantum-mechanical picture of the densities in a transversely polarized nucleon. We show that the correct N c -scaling of the charge and magnetization densities emerges as the result of the particular combination of currents generated by intermediate states with degenerate N and Δ. The off-shell behavior of the chiral EFT is summarized in contact terms and can be studied easily. The methods developed here can be applied to other peripheral densities and to moments of the nucleon's generalized parton distributions.
Sharma, Harshita; Zerbe, Norman; Heim, Daniel; Wienert, Stephan; Lohmann, Sebastian; Hellwich, Olaf; Hufnagl, Peter
2016-03-01
This paper describes a novel graph-based method for efficient representation and subsequent classification in histological whole slide images of gastric cancer. Her2/neu immunohistochemically stained and haematoxylin and eosin stained histological sections of gastric carcinoma are digitized. Immunohistochemical staining is used in practice by pathologists to determine extent of malignancy, however, it is laborious to visually discriminate the corresponding malignancy levels in the more commonly used haematoxylin and eosin stain, and this study attempts to solve this problem using a computer-based method. Cell nuclei are first isolated at high magnification using an automatic cell nuclei segmentation strategy, followed by construction of cell nuclei attributed relational graphs of the tissue regions. These graphs represent tissue architecture comprehensively, as they contain information about cell nuclei morphology as vertex attributes, along with knowledge of neighborhood in the form of edge linking and edge attributes. Global graph characteristics are derived and ensemble learning is used to discriminate between three types of malignancy levels, namely, non-tumor, Her2/neu positive tumor and Her2/neu negative tumor. Performance is compared with state of the art methods including four texture feature groups (Haralick, Gabor, Local Binary Patterns and Varma Zisserman features), color and intensity features, and Voronoi diagram and Delaunay triangulation. Texture, color and intensity information is also combined with graph-based knowledge, followed by correlation analysis. Quantitative assessment is performed using two cross validation strategies. On investigating the experimental results, it can be concluded that the proposed method provides a promising way for computer-based analysis of histopathological images of gastric cancer.
ZHANG YunHong; GUO ChunYan
2008-01-01
An event-related potential study was conducted to make clear the relationships between perceptual and semantic levels of representation. Subjects judged the semantic relationship between a picture sample and a word match using the delayed match-to-sample paradigm. The experiment includes three types of matching trials, i.e., identical match trials, where the words had the same meanings as the pictures, categorical match trials where the words matched the pictures in category, and non-match trials where the words matched neither in identification nor in category with the pictures. The three conditions evoke significantly different N400-1ike and P300 ERP components. Specifically, for the N400-like negative responses, the averaged amplitude of the non-match condition is the largest and the most negative-going, that of the categorical match condition is less negative-going, and that of the identical match condition is the smallest among all three conditions. In addition, only the identical match condition evokes an early P300 component. As for the late P300 component, the averaged amplitude of the categorical match condition is more robust in the frontal brain areas. In contrast, ERPs of the non-match condition are stronger in the posterior brain areas. From 250 to 450 ms, the difference waves between the identical match and non-match conditions are located in the central areas, and the difference waves between categorical match and non-match conditions occur in the right frontal areas.Our results suggest that cross-form picture-word identical matching and categorical matching involve different underlying mechanisms. The existence of the early P300 component evokes by the identical match condition provides support for theories of template matching and facilitation model.
Zvi N Roth
2016-03-01
Full Text Available Neural responses in visual cortex are governed by a topographic mapping from retinal locations to cortical responses. Moreover, at the voxel population level early visual cortex (EVC activity enables accurate decoding of stimuli locations. However, in many cases information enabling one to discriminate between locations (i.e. discriminative information may be less relevant than information regarding the relative location of two objects (i.e. relative information. For example, when planning to grab a cup, determining whether the cup is located at the same retinal location as the hand is hardly relevant, whereas the location of the cup relative to the hand is crucial for performing the action.We have previously used multivariate pattern analysis techniques to measure discriminative location information, and found the highest levels in early visual cortex, in line with other studies. Here we show, using representational similarity analysis, that availability of discriminative information in fMRI activation patterns does not entail availability of relative information. Specifically, we find that relative location information can be reliably extracted from activity patterns in posterior intraparietal sulcus (pIPS, but not from EVC, where we find the spatial representation to be warped.We further show that this variability in relative information levels between regions can be explained by a computational model based on an array of receptive fields. Moreover, when the model’s receptive fields are extended to include inhibitory surround regions, the model can account for the spatial warping in EVC.These results demonstrate how size and shape properties of receptive fields in human visual cortex contribute to the transformation of discriminative spatial representation into relative spatial representation along the visual stream.
Roth, Zvi N
2016-01-01
Neural responses in visual cortex are governed by a topographic mapping from retinal locations to cortical responses. Moreover, at the voxel population level early visual cortex (EVC) activity enables accurate decoding of stimuli locations. However, in many cases information enabling one to discriminate between locations (i.e., discriminative information) may be less relevant than information regarding the relative location of two objects (i.e., relative information). For example, when planning to grab a cup, determining whether the cup is located at the same retinal location as the hand is hardly relevant, whereas the location of the cup relative to the hand is crucial for performing the action. We have previously used multivariate pattern analysis techniques to measure discriminative location information, and found the highest levels in EVC, in line with other studies. Here we show, using representational similarity analysis, that availability of discriminative information in fMRI activation patterns does not entail availability of relative information. Specifically, we find that relative location information can be reliably extracted from activity patterns in posterior intraparietal sulcus (pIPS), but not from EVC, where we find the spatial representation to be warped. We further show that this variability in relative information levels between regions can be explained by a computational model based on an array of receptive fields. Moreover, when the model's receptive fields are extended to include inhibitory surround regions, the model can account for the spatial warping in EVC. These results demonstrate how size and shape properties of receptive fields in human visual cortex contribute to the transformation of discriminative spatial representations into relative spatial representations along the visual stream.
Roth, Zvi N.
2016-01-01
Neural responses in visual cortex are governed by a topographic mapping from retinal locations to cortical responses. Moreover, at the voxel population level early visual cortex (EVC) activity enables accurate decoding of stimuli locations. However, in many cases information enabling one to discriminate between locations (i.e., discriminative information) may be less relevant than information regarding the relative location of two objects (i.e., relative information). For example, when planning to grab a cup, determining whether the cup is located at the same retinal location as the hand is hardly relevant, whereas the location of the cup relative to the hand is crucial for performing the action. We have previously used multivariate pattern analysis techniques to measure discriminative location information, and found the highest levels in EVC, in line with other studies. Here we show, using representational similarity analysis, that availability of discriminative information in fMRI activation patterns does not entail availability of relative information. Specifically, we find that relative location information can be reliably extracted from activity patterns in posterior intraparietal sulcus (pIPS), but not from EVC, where we find the spatial representation to be warped. We further show that this variability in relative information levels between regions can be explained by a computational model based on an array of receptive fields. Moreover, when the model's receptive fields are extended to include inhibitory surround regions, the model can account for the spatial warping in EVC. These results demonstrate how size and shape properties of receptive fields in human visual cortex contribute to the transformation of discriminative spatial representations into relative spatial representations along the visual stream. PMID:27242455
Population coding of forelimb joint kinematics by peripheral afferents in monkeys.
Tatsuya Umeda
Full Text Available Various peripheral receptors provide information concerning position and movement to the central nervous system to achieve complex and dexterous movements of forelimbs in primates. The response properties of single afferent receptors to movements at a single joint have been examined in detail, but the population coding of peripheral afferents remains poorly defined. In this study, we obtained multichannel recordings from dorsal root ganglion (DRG neurons in cervical segments of monkeys. We applied the sparse linear regression (SLiR algorithm to the recordings, which selects useful input signals to reconstruct movement kinematics. Multichannel recordings of peripheral afferents were performed by inserting multi-electrode arrays into the DRGs of lower cervical segments in two anesthetized monkeys. A total of 112 and 92 units were responsive to the passive joint movements or the skin stimulation with a painting brush in Monkey 1 and Monkey 2, respectively. Using the SLiR algorithm, we reconstructed the temporal changes of joint angle, angular velocity, and acceleration at the elbow, wrist, and finger joints from temporal firing patterns of the DRG neurons. By automatically selecting a subset of recorded units, the SLiR achieved superior generalization performance compared with a regularized linear regression algorithm. The SLiR selected not only putative muscle units that were responsive to only the passive movements, but also a number of putative cutaneous units responsive to the skin stimulation. These results suggested that an ensemble of peripheral primary afferents that contains both putative muscle and cutaneous units encode forelimb joint kinematics of non-human primates.
Population coding and decoding in a neural field: a computational study.
Wu, Si; Amari, Shun-Ichi; Nakahara, Hiroyuki
2002-05-01
This study uses a neural field model to investigate computational aspects of population coding and decoding when the stimulus is a single variable. A general prototype model for the encoding process is proposed, in which neural responses are correlated, with strength specified by a gaussian function of their difference in preferred stimuli. Based on the model, we study the effect of correlation on the Fisher information, compare the performances of three decoding methods that differ in the amount of encoding information being used, and investigate the implementation of the three methods by using a recurrent network. This study not only rediscovers main results in existing literatures in a unified way, but also reveals important new features, especially when the neural correlation is strong. As the neural correlation of firing becomes larger, the Fisher information decreases drastically. We confirm that as the width of correlation increases, the Fisher information saturates and no longer increases in proportion to the number of neurons. However, we prove that as the width increases further--wider than (sqrt)2 times the effective width of the turning function--the Fisher information increases again, and it increases without limit in proportion to the number of neurons. Furthermore, we clarify the asymptotic efficiency of the maximum likelihood inference (MLI) type of decoding methods for correlated neural signals. It shows that when the correlation covers a nonlocal range of population (excepting the uniform correlation and when the noise is extremely small), the MLI type of method, whose decoding error satisfies the Cauchy-type distribution, is not asymptotically efficient. This implies that the variance is no longer adequate to measure decoding accuracy.
Yu Hu
2014-02-01
Full Text Available Over repeat presentations of the same stimulus, sensory neurons show variable responses. This "noise" is typically correlated between pairs of cells, and a question with rich history in neuroscience is how these noise correlations impact the population's ability to encode the stimulus. Here, we consider a very general setting for population coding, investigating how information varies as a function of noise correlations, with all other aspects of the problem - neural tuning curves, etc. - held fixed. This work yields unifying insights into the role of noise correlations. These are summarized in the form of theorems, and illustrated with numerical examples involving neurons with diverse tuning curves. Our main contributions are as follows. (1 We generalize previous results to prove a sign rule (SR - if noise correlations between pairs of neurons have opposite signs vs. their signal correlations, then coding performance will improve compared to the independent case. This holds for three different metrics of coding performance, and for arbitrary tuning curves and levels of heterogeneity. This generality is true for our other results as well. (2 As also pointed out in the literature, the SR does not provide a necessary condition for good coding. We show that a diverse set of correlation structures can improve coding. Many of these violate the SR, as do experimentally observed correlations. There is structure to this diversity: we prove that the optimal correlation structures must lie on boundaries of the possible set of noise correlations. (3 We provide a novel set of necessary and sufficient conditions, under which the coding performance (in the presence of noise will be as good as it would be if there were no noise present at all.
Adriaensen, B.Y.A.
2015-01-01
Ever since Felipe Calderón declared the war on drugs at the beginning of his presidency in 2006, violence has drastically permeated Mexican society. In this paper, I will focus on the different uses of dark humour and irony in the representation of the mutilated and abject body in contemporary Mexic
Heijmans, M.; Ridder, D. de; Bensing, J.
1999-01-01
In this cross-sectional study, the illness representations of patients suffering from Chronic Fatigue Syndrome (n=49) and Addison's Disease (n=52) and those of their spouses were compared. Couples generally held similar views with regard to the dimensions of illness identity and cause but disagreed
Van Schie, H.T.; Wijers, A.A.; Kellenbach, M.L; Stowe, L.A.
2003-01-01
The present study was conducted to investigate relationships between semantic and perceptual levels of representation. A picture - word repetition paradigm was used in which we manipulated the semantic relationship between pictures and words. Experiment I involved two types of trials, one with words
[Social representation related to care in the family health program in Natal-Brazil].
Rodrigues, Maísa Paulino; de Lima, Kenio Costa; Roncalli, Angelo Giuseppe
2008-01-01
This study examines the core and outlying representational elements of healthcare constructed by Family Healthcare Program teams in Natal, Brazil, using the theory of social representations and the central core theory. The sample consisted of ninety healthcare practitioners working with this Program, with data collected through free word association, a questionnaire and focus groups. The core representation consists of attention/love and comfort, disclosing different understandings and showing that accumulated knowledge is supported by a view that is close to care-giving. However, traditional values and trivial connotations are maintained, hindering the implementation of more effective interventions in by this Program. The core composition indicated that any capacity-building efforts that try to modify attitudes - and thus the daily practice of these practitioners - must assign high priority to discussions on redefining these elements of attention/love and comfort. They must consider the set of mental, emotional, and practical elaborations as well as explanations arising from daily life that are introduced into the constitution of the social representations under examination, influencing choices and shaping the strategies used by practitioners to provide care.
Heijmans, M.; Ridder, D. de; Bensing, J.
1999-01-01
In this cross-sectional study, the illness representations of patients suffering from Chronic Fatigue Syndrome (n=49) and Addison's Disease (n=52) and those of their spouses were compared. Couples generally held similar views with regard to the dimensions of illness identity and cause but disagreed
Adriaensen, B.Y.A.
2015-01-01
Ever since Felipe Calderón declared the war on drugs at the beginning of his presidency in 2006, violence has drastically permeated Mexican society. In this paper, I will focus on the different uses of dark humour and irony in the representation of the mutilated and abject body in contemporary
Oksana V. Belikova
2013-01-01
Full Text Available The article attempts to examine the methods of formal representation of euphemisms and dysphemisms, structurally represented as separate words, phrases or sentences, used in the English-language newspaper text. This analysis enables to take a fresh look at the essence of euphemisms and dysphemisms phenomena, many features of which went unnoticed in the previous theories.
Adriaensen, B.Y.A.
2015-01-01
Ever since Felipe Calderón declared the war on drugs at the beginning of his presidency in 2006, violence has drastically permeated Mexican society. In this paper, I will focus on the different uses of dark humour and irony in the representation of the mutilated and abject body in contemporary Mexic
Some Cognitive Difficulties Related to the Representations of Two Major Concepts of Set Theory
Bagni, Giorgio T.
2006-01-01
The main focus of this paper is on the study of students' conceptual understanding of two major concepts of Set Theory--the concepts of inclusion and belonging. To do so, we analyze two experimental classroom episodes. Our analysis rests on the theoretical idea that, from an ontogenetic viewpoint, the cognitive activity of representation of…
Johnson, Matthew R; McCarthy, Gregory; Muller, Kathleen A; Brudner, Samuel N; Johnson, Marcia K
2015-09-01
Refreshing is the component cognitive process of directing reflective attention to one of several active mental representations. Previous studies using fMRI suggested that refresh tasks involve a component process of initiating refreshing as well as the top-down modulation of representational regions central to refreshing. However, those studies were limited by fMRI's low temporal resolution. In this study, we used EEG to examine the time course of refreshing on the scale of milliseconds rather than seconds. ERP analyses showed that a typical refresh task does have a distinct electrophysiological response as compared to a control condition and includes at least two main temporal components: an earlier (∼400 msec) positive peak reminiscent of a P3 response and a later (∼800-1400 msec) sustained positivity over several sites reminiscent of the late directing attention positivity. Overall, the evoked potentials for refreshing representations from three different visual categories (faces, scenes, words) were similar, but multivariate pattern analysis showed that some category information was nonetheless present in the EEG signal. When related to previous fMRI studies, these results are consistent with a two-phase model, with the first phase dominated by frontal control signals involved in initiating refreshing and the second by the top-down modulation of posterior perceptual cortical areas that constitutes refreshing a representation. This study also lays the foundation for future studies of the neural correlates of reflective attention at a finer temporal resolution than is possible using fMRI.
Rasmussen, Majken Kirkegaard; Petersen, Marianne Graves
2011-01-01
Stereotypic presumptions about gender affect the design process, both in relation to how users are understood and how products are designed. As a way to decrease the influence of stereotypic presumptions in design process, we propose not to disregard the aspect of gender in the design process......, as the perspective brings valuable insights on different approaches to technology, but instead to view gender through a value lens. Contributing to this perspective, we have developed Value Representations as a design-oriented instrument for staging a reflective dialogue with users. Value Representations...
Morlot, Rachel; Laurin, Raphaël; Lacassagne, Marie-Françoise; Millot, Isabelle
2010-01-01
The aim of this paper is to carry out a survey and comparative analysis of social representations of physical activity and fruit and vegetables in a sample of young, adult and elderly subjects. Four "urban" areas and four "rural" areas were selected for the purposes of the investigation. The samples used to assess social representations of fruit and vegetables and physical activity included 132 and 153 participants respectively. Verbal association was used and a factorial correspondence analysis was applied to the data. The prevention messages delivered as part of the second national program of nutrition and health were integrated by adult participants. A very limited awareness of the benefits of eating fruit and vegetable was observed in the young population. This study underlines the importance of implementing regular measures for the purposes of qualitative local evaluations that consider the specific characteristics of every age group in order to assess the psychological impact of prevention campaigns.
Murray, Lynne; Pella, Jeff; De Pascalis, Leonardo; Arteche, Adriane; Pass, Laura; Percy, Ray; Creswell, Catharine; Cooper, Peter
2014-01-01
Anxious mothers’ parenting, particularly transfer of threat information, has been considered important in their children’s risk for social anxiety disorder (SAnxD), and maternal narratives concerning potential social threat could elucidate this contribution.\\ud Maternal narratives to their pre-school 4-5 year-old children, via a picture book about starting school, were assessed in socially anxious (N=73), and non-anxious (N=63) mothers. Child representations of school were assessed via Doll P...
Cannone, Patrice; Dany, Lionel; Dudoit, Eric; Duffaud, Florence; Salas, Sébastien; Favre, Roger
2004-03-01
This research aims to study social representations throughout chemiotherapy, out of a population composed of doctors specialized in Oncology on one hand, and patients dealing with cancer during their chemiotherapy on the other hand. Our methodology is situated among quantitative methods using SPSS for Anovas to analyze statistics datas, EVOQ and Alceste for the pragmatic analysis of the discourse. The datas were collected from a questionnaire including items and words associations. We were interested in chemiotherapy which appears as a social object likely to generate a representative process from which emerges a serie of adaptative strategies belonging to both cognitivo-behaviourism and emotional spheres. chemiotherapy leads to an adaptation of the patient and remains a mediator in the doctor-patient's relation. As far as representations are "action guides", the existence of a representation specific to patients and doctors, allowes us to point out, through a semantic and emotional gap a technical medicine which is, in the future, likely to tend to existentialism.
Leung, Christy Y Y; Miller, Alison L; Lumeng, Julie C; Kaciroti, Niko A; Rosenblum, Katherine L
2015-12-01
Identifying maternal characteristics in relation to child feeding is important for addressing the current childhood obesity epidemic. The present study examines whether maternal representations of their children are associated with feeding beliefs and practices. Maternal representations refer to mothers' affective and cognitive perspectives regarding their children and their subjective experiences of their relationships with their children. This key maternal characteristic has not been examined in association with maternal feeding. Thus the purpose of the current study was to examine whether maternal representations of their children, reflected by Working Model of the Child Interview typologies (Balanced, Disengaged, or Distorted), were associated with maternal feeding beliefs (Authority, Confidence, and Investment) and practices (Pressure to Eat, Restriction, and Monitoring) among low-income mothers of young children, with maternal education examined as a covariate. Results showed that Balanced mothers were most likely to demonstrate high authority, Distorted mothers were least likely to demonstrate confidence, and Disengaged mothers were least likely to demonstrate investment in child feeding. Moreover, Balanced mothers were least likely to pressure their children to eat. Findings are discussed with regard to implications for the study of childhood obesity and for applied preventions.
A shared representation of the space near oneself and others in the human premotor cortex.
Brozzoli, Claudio; Gentile, Giovanni; Bergouignan, Loretxu; Ehrsson, H Henrik
2013-09-23
Interactions between people require shared high-level cognitive representations of action goals, intentions, and mental states, but do people also share their representation of space? The human ventral premotor (PMv) and parietal cortices contain neuronal populations coding for the execution and observation of actions, analogous to the mirror neurons identified in monkeys. This neuronal system is tuned to the location of the acting person relative to the observer and the target of the action. Therefore, it can be theorized that the observer's brain constructs a low-level, body-centered representation of the space around others similar to one's own peripersonal space representation. Single-cell recordings have reported that parietal visuotactile neurons discharge for objects near specific parts of a monkey's own body and near the corresponding body parts of another individual. In humans, no neuroimaging study has investigated this issue. Here, we identified neuronal populations in the human PMv that encode the space near both one's own hand and another person's hand. The shared peripersonal space representation could support social interactions by coding sensory events, actions, and cognitive processes in a common spatial reference frame.
Understanding Neural Population Coding: Information Theoretic Insights from the Auditory System
Arno Onken
2014-01-01
Full Text Available In recent years, our research in computational neuroscience has focused on understanding how populations of neurons encode naturalistic stimuli. In particular, we focused on how populations of neurons use the time domain to encode sensory information. In this focused review, we summarize this recent work from our laboratory. We focus in particular on the mathematical methods that we developed for the quantification of how information is encoded by populations of neurons and on how we used these methods to investigate the encoding of complex naturalistic sounds in auditory cortex. We review how these methods revealed a complementary role of low frequency oscillations and millisecond precise spike patterns in encoding complex sounds and in making these representations robust to imprecise knowledge about the timing of the external stimulus. Further, we discuss challenges in extending this work to understand how large populations of neurons encode sensory information. Overall, this previous work provides analytical tools and conceptual understanding necessary to study the principles of how neural populations reflect sensory inputs and achieve a stable representation despite many uncertainties in the environment.
The Dynamical Yang-Baxter Relation and the Minimal Representation of the Elliptic Quantum Group
Fan, H; Shi, K J; Yue, R H; Zhao, S Y; Fan, Heng; Hou, Bo-Yu; Shi, Kang-Jie; Yue, Rui-Hong; Zhao, Shao-You
2003-01-01
In this paper, we give the general forms of the minimal $L$ matrix (the elements of the $L$-matrix are $c$ numbers) associated with the Boltzmann weights of the $A_{n-1}^1$ interaction-round-a-face (IRF) model and the minimal representation of the $A_{n-1}$ series elliptic quantum group given by Felder and Varchenko. The explicit dependence of elements of $L$-matrices on spectral parameter $z$ are given. They are of five different forms (A(1-4) and B). The algebra for the coefficients (which do not depend on $z$) are given. The algebra of form A is proved to be trivial, while that of form B obey Yang-Baxter equation (YBE). We also give the PBW base and the centers for the algebra of form B.
Social representations of adolescents on sexual relations and the use of condoms
Elys de Oliveira Bezerra
Full Text Available The objective of this investigation was to identify how adolescents structure the social representations of sexual intercourse and use of condoms. Exploratory and descriptive research was conducted with a convenience sample consisting of 234 students of a public secondary school in Fortaleza-CE, Brazil, between July 2009 and April 2010. Data were collected using a questionnaire with variables on socioeconomic status and sexual behaviour, and Free Association test with three terms: 'sex', 'unprotected sex' and 'sex with a condom'. Sexual intercourse was represented by love and affection among the women, while men associated sex to pleasure, desire and attraction toward the female body. The condom was considered important by both groups, but men represented condoms as being something bad that restricts pleasure. Health professionals are granted the opportunity to identify vulnerabilities of this population to DST/HIV/AIDS and work with these vulnerabilities in the most appropriate way.
Goutte, Stéphane; Russo, Francesco
2012-01-01
Given a process with independent increments $X$ (not necessarily a martingale) and a large class of square integrable r.v. $H=f(X_T)$, $f$ being the Fourier transform of a finite measure $\\mu$, we provide explicit Kunita-Watanabe and F\\"ollmer-Schweizer decompositions. The representation is expressed by means of two significant maps: the expectation and derivative operators related to the characteristics of $X$. We also provide an explicit expression for the variance optimal error when hedging the claim $H$ with underlying process $X$. Those questions are motivated by finding the solution of the celebrated problem of global and local quadratic risk minimization in mathematical finance.
Mendoza-Halliday, Diego; Martinez-Trujillo, Julio C.
2017-01-01
The primate lateral prefrontal cortex (LPFC) encodes visual stimulus features while they are perceived and while they are maintained in working memory. However, it remains unclear whether perceived and memorized features are encoded by the same or different neurons and population activity patterns. Here we record LPFC neuronal activity while monkeys perceive the motion direction of a stimulus that remains visually available, or memorize the direction if the stimulus disappears. We find neurons with a wide variety of combinations of coding strength for perceived and memorized directions: some neurons encode both to similar degrees while others preferentially or exclusively encode either one. Reading out the combined activity of all neurons, a machine-learning algorithm reliably decode the motion direction and determine whether it is perceived or memorized. Our results indicate that a functionally diverse population of LPFC neurons provides a substrate for discriminating between perceptual and mnemonic representations of visual features. PMID:28569756
Elisabetta eCoppi
2014-08-01
Full Text Available To better understand the physiological mechanisms responsible for the differential motor cortex functioning in aging, we used transcranial magnetic stimulation to investigate interhemispheric interactions and cortical representation of hand muscles in the early phase of physiological aging, correlating these data with participants’ motor abilities.Right-handed healthy subjects were divided into a younger group (n=15, 25.4 ± 1.9 y.o and an older group (n=16, mean age 61.1 ± 5.1 y.o. Activity of the bilateral abductor pollicis brevis (APB and abductor digiti minimi (ADM was recorded. Ipsilateral silent period (ISP was measured in both APBs. Cortical maps of APB and ADM were measured bilaterally. Mirror movements (MM were recorded during thumb abductions. Motor abilities were tested using Nine Hole Peg Test (NHPT, finger tapping (FT and grip strength. ISP was reduced in the older group on both sides, in terms of duration (p=0.025, onset (p=0.029 and area (p=0.008. RMT did not differ between groups. APB and ADM maps were symmetrical in the younger group, but were reduced on the right compared to the left hemisphere in the older group (p=0.008. The APB map of the right hemisphere was reduced in the older group compared to the younger (p=0.021. Older subjects showed higher frequency of MM and worse motor abilities (p<0.001. The reduction of right ISP area correlated significantly with the worsening of motor performances.Our results showed decreased interhemispheric interactions in the early processes of physiological aging and a decreased cortical muscles representation over the non-dominant hemisphere. The decreased ISP and increased frequency of MM suggest a reduction of transcallosal inhibition. These data demonstrate that early processes of normal aging are marked by a dissociation of motor cortices, characterized, at least, by a decline of the non-dominant hemisphere, reinforcing the hypothesis of the right hemi-aging model.
Chui-De eChiu
2016-04-01
and psychosis. An altered sense of individuality embedded in self-referential representations appears to be a common sociocognitive deficit of dissociation and psychosis.
Iatsenko, Dmytro; Stefanovska, Aneta
2013-01-01
Time-frequency representations (TFRs) of signals, such as windowed Fourier transform (WFT), wavelet transform (WT) and their synchrosqueezed variants (SWFT, SWT), provide powerful analysis tools. However, there are many important issues related to the practical use of TFRs that need to be clarified. Here we present a thorough review of these TFRs, summarizing all theoretical, practical and numerical aspects of their use, reconsidering some conventions and introducing new concepts and procedures. The purposes of this work are: (i) to provide a consistent overview of the computation, properties, and use of the (S)WFT/(S)WT methods; (ii) to establish general standards related to their use, both theoretical and practical; and (iii) to provide clean and optimized algorithms and MatLab codes, appropriate for any window or wavelet.
Ashkenazi, Sarit; Rosenberg-Lee, Miriam; Tenison, Caitlin; Menon, Vinod
2012-02-15
Developmental dyscalculia (DD) is a disability that impacts math learning and skill acquisition in school-age children. Here we investigate arithmetic problem solving deficits in young children with DD using univariate and multivariate analysis of fMRI data. During fMRI scanning, 17 children with DD (ages 7-9, grades 2 and 3) and 17 IQ- and reading ability-matched typically developing (TD) children performed complex and simple addition problems which differed only in arithmetic complexity. While the TD group showed strong modulation of brain responses with increasing arithmetic complexity, children with DD failed to show such modulation. Children with DD showed significantly reduced activation compared to TD children in the intraparietal sulcus, superior parietal lobule, supramarginal gyrus and bilateral dorsolateral prefrontal cortex in relation to arithmetic complexity. Critically, multivariate representational similarity revealed that brain response patterns to complex and simple problems were less differentiated in the DD group in bilateral anterior IPS, independent of overall differences in signal level. Taken together, these results show that children with DD not only under-activate key brain regions implicated in mathematical cognition, but they also fail to generate distinct neural responses and representations for different arithmetic problems. Our findings provide novel insights into the neural basis of DD.
L'Education relative a l'environnement: La representation sociale d'educatrices et d'educateurs
Rooney, Elizabeth
Cette recherche, qui prend appui sur la theorie des representations sociales, a tente de comprendre le phenomene de l'Education relative a l'environnement (ERE) au Quebec. Pour ce faire, j'ai choisi de m'interesser aux points de vue sur le sujet de neuf enseignantes et enseignants d'ecologie oeuvrant dans des ecoles (contexte formel) et de dix animatrices et animateurs oeuvrant dans des centres d'interpretation (contexte non formel). L'analyse narrative de leurs discours recueillis lors d'entrevues individuelles semi-structurees a permis de montrer que la mise en forme et la mise en pratique de l'ERE tendent a s'inscrire dans le prolongement d'une conception essentiellement ecologique de l'environnement et d'une conception plutot mecaniste et sensualiste de l'education, c'est-a-dire comme une simple affaire de transmission de connaissances scientifiques et d'eveil d'acuite sensorielle. Cette analyse a egalement permis de montrer que les educatrices et les educateurs retravaillent ces conceptions pour composer avec les moments et les lieux singuliers de leurs pratiques. Ce faisant, ils innovent et soulevent des questions a propos de la teneur des conceptions ou definitions standardisees de l'ERE. Cette recherche permet ainsi d'eclairer l'aspect a la fois traditionnel et potentiellement innovateur de la representation sociale de l'ERE d'educatrices et d'educateurs de terrain.
Winskell, Kate; Hill, Elizabeth; Obyerodhyambo, Oby
2011-01-01
HIV-related symbolic stigma arises from moralistic value judgements attached to people living with HIV and has negative consequences from both public health and human rights perspectives. Relatively little is known about cross-national variation in symbolic stigma. With the purpose of informing stigma reduction efforts within and across settings, we compared social representations of HIV in six African countries with estimated adult HIV prevalence rates ranging from 1 to 33%. Our study used a unique data source, namely a stratified random sample (n=586, ~5%) from 11,354 creative ideas contributed from six countries to a continent-wide HIV-related scriptwriting contest held between February and April2005. The narratives were written by equal numbers of males and females aged 10–24 in urban and rural areas of Swaziland, Namibia, Kenya, South-East Nigeria, Burkina Faso and Senegal. We combined three analytical approaches: descriptive statistics on certain quantifiable characteristics of the narratives, thematic data analysis, and a narrative-based approach. The association of HIV with outsiders (“othering”)and preoccupation with the circumstances of infection are more common in lower prevalence countries but vary substantially in tone depending on the sociocultural context. The highest proportion both of moralising narratives and of narratives with pessimistic outcomes come from South-East Nigeria and, to a lesser extent, from Kenya, countries with prevalence levels of 3.9 and 6.1% respectively, in which evangelical Christian movements, including Pentecostalism, have sizeable followings. The data provide a rare cross-cultural overview of symbolic stigma, identify country-specific needs, and point to strategies for future programming. Social representations from the highest prevalence countries, Swaziland and Namibia, and from lower prevalence Burkina Faso offer potential models for the framing of HIV in ways that serve to increase social proximity and counteract
Zhou, L; Lu, Y; Vitale, C J; Mar, P L; Chang, F; Dhopeshwarkar, N; Rocha, R A
2014-01-01
The ability to manage and leverage family history information in the electronic health record (EHR) is crucial to delivering high-quality clinical care. We aimed to evaluate existing standards in representing relative information, examine this information documented in EHRs, and develop a natural language processing (NLP) application to extract relative information from free-text clinical documents. We reviewed a random sample of 100 admission notes and 100 discharge summaries of 198 patients, and also reviewed the structured entries for these patients in an EHR system's family history module. We investigated the two standards used by Stage 2 of Meaningful Use (SNOMED CT and HL7 Family History Standard) and identified coverage gaps of each standard in coding relative information. Finally, we evaluated the performance of the MTERMS NLP system in identifying relative information from free-text documents. The structure and content of SNOMED CT and HL7 for representing relative information are different in several ways. Both terminologies have high coverage to represent local relative concepts built in an ambulatory EHR system, but gaps in key concept coverage were detected; coverage rates for relative information in free-text clinical documents were 95.2% and 98.6%, respectively. Compared to structured entries, richer family history information was only available in free-text documents. Using a comprehensive lexicon that included concepts and terms of relative information from different sources, we expanded the MTERMS NLP system to extract and encode relative information in clinical documents and achieved a corresponding precision of 100% and recall of 97.4%. Comprehensive assessment and user guidance are critical to adopting standards into EHR systems in a meaningful way. A significant portion of patients' family history information is only documented in free-text clinical documents and NLP can be used to extract this information.
Representations of a Noncommutative Associative Algebra Related to Quantum Torus of Rank Three
Shang Yuan LIN; Bin XIN
2005-01-01
In this paper, we present some modules over the rank-three quantized Weyl algebra, which are closely related to modules over some vertex algebras. The isomorphism classes among these modules are also determined.
Nader Ali Makboul Hassan
2014-01-01
Full Text Available This paper is an attempt to stress the usefulness of the multi-variable special functions. In this paper, we derive certain generating relations involving 2-indices 5-variables 5-parameters Tricomi functions (2I5V5PTF by using a Lie-algebraic method. Further, we derive certain new and known generating relations involving other forms of Tricomi and Bessel functions as applications.
Francesc Valls Dalmau
2014-10-01
Full Text Available Digesting the data hose that cities are constantly producing is complex; data is usually structured with different criteria, which makes comparative analysis of multiple cities challenging. However, the publicly available data from the Spanish cadaster contains urban information in a documented format with common semantics for the whole territory, which makes these analyses possible. This paper uses the information about the 3D geometry of buildings, their use and their year of construction, stored in cadastral databases, to study the relation between the built environment (what the city is and the urban plan (what the city wants to become, translating the concepts of the cadastral data into the semantics of the urban plan. Different representation techniques to better understand the city from the pedestrians’ point of view and to communicate this information more effectively are also discussed.
Differential representation of arm movement direction in relation to cortical anatomy and function
Ball, Tonio; Schulze-Bonhage, Andreas; Aertsen, Ad; Mehring, Carsten
2009-02-01
Information about arm movement direction in neuronal activity of the cerebral cortex can be used for movement control mediated by a brain-machine interface (BMI). Here we provide a topographic analysis of the information related to arm movement direction that can be extracted from single trials of electrocorticographic (ECoG) signals recorded from the human frontal and parietal cortex based on a precise assignment of ECoG recording channels to the subjects' individual cortical anatomy and function. To this aim, each electrode contact was identified on structural MRI scans acquired while the electrodes were implanted and was thus related to the brain anatomy of each patient. Cortical function was assessed by direct cortical electrical stimulation. We show that activity from the primary motor cortex, in particular from the region showing hand and arm motor responses upon electrical stimulation, carries most directional information. The premotor, posterior parietal and lateral prefrontal cortex contributed gradually less, but still significant information. This gradient was observed for decoding from movement-related potentials, and from spectral amplitude modulations in low frequencies and in the high gamma band. Our findings thus demonstrate a close topographic correlation between cortical functional anatomy and direction-related information in humans that might be used for brain-machine interfacing.
Behrmann, Marlene; Peterson, Mary A.; Moscovitch, Morris; Suzuki, Satoru
2006-01-01
Whether objects are represented as a collection of parts whose relations are coded independently remains a topic of ongoing discussion among theorists in the domain of shape perception. S. M., an individual with integrative agnosia, and neurologically intact ("normal") individuals learned initially to identify 4 target objects constructed of 2…
Representations in human visual short-term memory : an event-related brain potential study
Klaver, P; Smid, HGOM; Heinze, HJ
1999-01-01
Behavioral measures and event-related potentials (ERPs) were recorded from 12 subjects while performing three delayed matching-to-sample tasks. The task instructions indicated whether stimulus locations, shapes or conjunctions of locations and shapes had to be memorized and matched against a probe.
Behrmann, Marlene; Peterson, Mary A.; Moscovitch, Morris; Suzuki, Satoru
2006-01-01
Whether objects are represented as a collection of parts whose relations are coded independently remains a topic of ongoing discussion among theorists in the domain of shape perception. S. M., an individual with integrative agnosia, and neurologically intact ("normal") individuals learned initially to identify 4 target objects constructed of 2…
Michael S. Milgram
2013-01-01
Full Text Available Contour integral representations of Riemann's Zeta function and Dirichlet's Eta (alternating Zeta function are presented and investigated. These representations flow naturally from methods developed in the 1800s, but somehow they do not appear in the standard reference summaries, textbooks, or literature. Using these representations as a basis, alternate derivations of known series and integral representations for the Zeta and Eta function are obtained on a unified basis that differs from the textbook approach, and results are developed that appear to be new.
João Wachelke
Full Text Available While the investigation of social representation contents through the analysis of word associations is convenient, it does not directly inform about the nature of relationships that representation elements maintain with the social object. This paper presents a qualitative technique, Qualiquic, that is easy and simple to administer. Qualiquic has the advantage of gathering representation contents characterized by their relationships with the representation object, based on a simplified list of descriptive, practical, and evaluative connectors of the basic cognitive schemes model. The underlying theoretical principles are explained, and empirical guidelines are provided, as well as an empirical example of use.
[Representation of women in health-related scientific societies in Spain in 2014].
Casado-Mejía, Rosa; Botello-Hermosa, Alicia
2015-01-01
To describe the presence of women in the governance of health-related scientific societies in Spain today. Spanish scientific societies were identified by vising the websites of the Ministry of Health, Social Services and Equality, and Fisterra. The sex of the president, executive officers and the board of directors was identified. Data were analyzed according to the overall percentage of women and by profession and setting. Of 173 scientific societies in July 2014, 41 had a female president (22.53%). Women held 35.45% of executive positions and accounted for 36.32% of the boards of directors. Only 16.07% of medical societies had a female president compared with 76.92% of nursing societies. Primary care societies had more women in executive positions (54.55%) than societies in which the professional activity of members involved both primary and secondary care (35.74%) and societies related to hospital care (27.93%). There is a lack of parity, which is greater in nursing and primary care societies than in medical and hospital-related societies. Parity decreases as the level of responsibility rises. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.
Montijn, J.S.; Vinck, M.; Pennartz, C.M.A.
2014-01-01
The primary visual cortex is an excellent model system for investigating how neuronal populations encode information, because of well-documented relationships between stimulus characteristics and neuronal activation patterns. We used two-photon calcium imaging data to relate the performance of
A Space-Economic Representation of Transitive Closures in Relational Databases
Yangjun Chen
2006-10-01
Full Text Available A composite object represented as a directed graph (digraph for short is an important data structure that requires efficient support in CAD/CAM, CASE, office systems, software management, web databases, and document databases. It is cumbersome to handle such objects in relational database systems when they involve ancestor-descendant relationships (or say, recursive relationships. In this paper, we present a new encoding method to label a digraph, which reduces the footprints of all previous strategies. This method is based on a tree labeling method and the concept of branchings that are used in graph theory for finding the shortest connection networks. A branching is a subgraph of a given digraph that is in fact a forest, but covers all the nodes of the graph. On the one hand, the proposed encoding scheme achieves the smallest space requirements among all previously published strategies for recognizing recursive relationships. On the other hand, it leads to a new algorithm for computing transitive closures for DAGs (directed acyclic graph in O(eþb time and O(nþb space, where n represents the number of the nodes of a DAG, e the numbers of the edges, and b the DAG's breadth. In addition, this method can be extended to cyclic digraphs and is especially suitable for a relational environment.
Cushing, Donish; Gazzaley, Adam; Morsella, Ezequiel
2017-07-20
Percepts and action-related urges often enter consciousness insuppressibly. The Reflexive Imagery Task (RIT) was developed to investigate how high-level cognitions (e.g., subvocalizations), too, can enter consciousness in this manner. Limitations of the paradigm include (a) that no data have confirmed subjects' introspections about the involuntary subvocalizations, and (b) that, in everyday life, adaptive responses to involuntary cognitions often depend on the nature of the other contents in consciousness. To address a and b, we developed an RIT in which subjects were presented with visual objects and instructed to not think of the object names. If a subvocalization did arise, however, subjects responded motorically only if the subvocalization rhymed with a word held in memory and if there was a visual "go" cue. Subjects successfully (on 0.83 of the trials) emitted this complex, "multi-determined" response, which provides evidence for the occurrence of the involuntary subvocalizations and illuminates the function of consciousness. Copyright © 2017 Elsevier Inc. All rights reserved.
Never resting brain: simultaneous representation of two alpha related processes in humans.
Eti Ben-Simon
Full Text Available Brain activity is continuously modulated, even at "rest". The alpha rhythm (8-12 Hz has been known as the hallmark of the brain's idle-state. However, it is still debated if the alpha rhythm reflects synchronization in a distributed network or focal generator and whether it occurs spontaneously or is driven by a stimulus. This EEG/fMRI study aimed to explore the source of alpha modulations and their distribution in the resting brain. By serendipity, while computing the individually defined power modulations of the alpha-band, two simultaneously occurring components of these modulations were found. An 'induced alpha' that was correlated with the paradigm (eyes open/ eyes closed, and a 'spontaneous alpha' that was on-going and unrelated to the paradigm. These alpha components when used as regressors for BOLD activation revealed two segregated activation maps: the 'induced map' included left lateral temporal cortical regions and the hippocampus; the 'spontaneous map' included prefrontal cortical regions and the thalamus. Our combined fMRI/EEG approach allowed to computationally untangle two parallel patterns of alpha modulations and underpin their anatomical basis in the human brain. These findings suggest that the human alpha rhythm represents at least two simultaneously occurring processes which characterize the 'resting brain'; one is related to expected change in sensory information, while the other is endogenous and independent of stimulus change.
Davidovitz, Rivka; Mikulincer, Mario; Shaver, Phillip R; Izsak, Ronit; Popper, Micha
2007-10-01
In 3 studies, the authors examined the contribution of leaders' attachment styles to their leadership motives and beliefs and to followers' outcomes. In Study 1, participants completed measures of attachment orientation, leadership motives, self-representations, and leadership style. Studies 2 and 3 were conducted within Israeli military units either during a leadership workshop or during intensive combat training. Israeli military officers and their soldiers (followers) reported on their attachment styles, and the soldiers reported on the officers' leadership qualities and on the soldiers' own performance and mental health. Leaders' attachment anxiety was associated with more self-serving leadership motives and with poorer leadership qualities in task-oriented situations. Leaders' attachment anxiety also predicted followers' poorer instrumental functioning. Leaders' attachment-related avoidance was negatively associated with prosocial motives to lead, with the failure to act as a security provider, and with followers' poorer socioemotional functioning and poorer long-range mental health. Results are discussed with respect to the value of attachment theory for the study of leadership.
Rispens, Judith; Baker, Anne
2012-01-01
Purpose: This study investigates the relative contributions of phonological short-term memory and phonological representations to nonword repetition (NWR). This was evaluated in children with specific language impairment (SLI) and/or reading impairment (RI); it was also studied from a developmental perspective by comparing 2 groups of typically…
Zeitlin, Anton M
2015-01-01
This article focuses on two related topics: unitary representations of the loop $ax+b$-group and their relation to a loop version of the $\\Gamma$-function and the construction of continuous series for the $\\widehat{sl(2,\\mathbb{R})}$-algebra. Mainly this is a survey of some results from arXiv:1012.4826 , arXiv:1210.2135 alongside with the motivation for them both from the physical and mathematical points of view.
Bauer, Johannes; Dávila-Chacón, Jorge; Wermter, Stefan
2015-10-01
Humans and other animals have been shown to perform near-optimally in multi-sensory integration tasks. Probabilistic population codes (PPCs) have been proposed as a mechanism by which optimal integration can be accomplished. Previous approaches have focussed on how neural networks might produce PPCs from sensory input or perform calculations using them, like combining multiple PPCs. Less attention has been given to the question of how the necessary organisation of neurons can arise and how the required knowledge about the input statistics can be learned. In this paper, we propose a model of learning multi-sensory integration based on an unsupervised learning algorithm in which an artificial neural network learns the noise characteristics of each of its sources of input. Our algorithm borrows from the self-organising map the ability to learn latent-variable models of the input and extends it to learning to produce a PPC approximating a probability density function over the latent variable behind its (noisy) input. The neurons in our network are only required to perform simple calculations and we make few assumptions about input noise properties and tuning functions. We report on a neurorobotic experiment in which we apply our algorithm to multi-sensory integration in a humanoid robot to demonstrate its effectiveness and compare it to human multi-sensory integration on the behavioural level. We also show in simulations that our algorithm performs near-optimally under certain plausible conditions, and that it reproduces important aspects of natural multi-sensory integration on the neural level.
Maionchi-Pino, Norbert; Taki, Yasuyuki; Yokoyama, Satoru; Magnan, Annie; Takahashi, Kei; Hashizume, Hiroshi; Ecalle, Jean; Kawashima, Ryuta
2013-01-01
To date, the nature of the phonological deficit in developmental dyslexia is still debated. We concur with possible impairments in the representations of the universal phonological constraints that universally govern how phonemes co-occur as a source of this deficit. We were interested in whether-and how-dyslexic children have sensitivity to…
Króliczak, Gregory; Piper, Brian J; Frey, Scott H
2016-12-01
Data from focal brain injury and functional neuroimaging studies implicate a distributed network of parieto-fronto-temporal areas in the human left cerebral hemisphere as playing distinct roles in the representation of meaningful actions (praxis). Because these data come primarily from right-handed individuals, the relationship between left cerebral specialization for praxis representation and hand dominance remains unclear. We used functional magnetic resonance imaging (fMRI) to evaluate the hypothesis that strongly left-handed (right hemisphere motor dominant) adults also exhibit this left cerebral specialization. Participants planned familiar actions for subsequent performance with the left or right hand in response to transitive (e.g., "pounding") or intransitive (e.g. "waving") action words. In linguistic control trials, cues denoted non-physical actions (e.g., "believing"). Action planning was associated with significant, exclusively left-lateralized and extensive increases of activity in the supramarginal gyrus (SMg), and more focal modulations in the left caudal middle temporal gyrus (cMTg). This activity was hand- and gesture-independent, i.e., unaffected by the hand involved in subsequent action performance, and the type of gesture (i.e., transitive or intransitive). Compared directly with right-handers, left-handers exhibited greater involvement of the right angular gyrus (ANg) and dorsal premotor cortex (dPMC), which is indicative of a less asymmetric functional architecture for praxis representation. We therefore conclude that the organization of mechanisms involved in planning familiar actions is influenced by one's motor dominance. However, independent of hand dominance, the left SMg and cMTg are specialized for ideomotor transformations-the integration of conceptual knowledge and motor representations into meaningful actions. These findings support the view that higher-order praxis representation and lower-level motor dominance rely on dissociable
Hamilton-West, Kate E; Milne, Alisoun J; Chenery, Alison; Tilbrook, Carolyn
2010-10-01
Despite the importance of early diagnosis of dementia, little is known about the factors underlying help-seeking in relation to signs of the condition. In this pilot study, we aimed to examine the potential utility of the common sense model (CSM) of illness representations for understanding lay perceptions of dementia and predicting intentions to seek help in relation to possible signs and symptoms. A secondary aim was to develop a measure of (dementia-related) illness representations as a tool for future research. After reading a vignette describing a "relative" with mild or moderate dementia, participants (N = 118) completed measures of illness representations and help-seeking intentions. Analyses compared perceptions of the mild and moderate vignettes and determined the extent to which illness perceptions differentiated between alternative forms of help-seeking (e.g. seeking professional help vs. help from family members). Results indicated that cognitive deficits were more readily identified as dementia than non-cognitive symptoms; these were commonly attributed to stress or depression. Participants were more likely to indicate an intention to seek professional help if they identified the problem in the vignette as dementia, perceived symptoms as severe, as having serious consequences and as likely to be permanent, but less likely to do so if they identified the problem as stress or attributed symptoms to psychological causes. Our preliminary data suggests that help-seeking may be prevented by inaccurate illness representations or misattribution of symptoms. The CSM may provide a useful framework for understanding perceptions of dementia symptoms and for informing help-seeking pathways.
Doran, C F; Gates, S J; Hübsch, T; Iga, K M; Landweber, G D
2008-01-01
Previous work has shown that the classification of indecomposable off-shell representations of N-supersymmetry, depicted as Adinkras, may be factored into specifying the topologies available to Adinkras, and then the height-assignments for each topological type. The latter problem being solved by a recursive mechanism that generates all height-assignments within a topology, it remains to classify the former. Herein we show that this problem is equivalent to classifying certain (1) graphs and (2) error-correcting codes.
Sparse representation of group-wise FMRI signals.
Lv, Jinglei; Li, Xiang; Zhu, Dajiang; Jiang, Xi; Zhang, Xin; Hu, Xintao; Zhang, Tuo; Guo, Lei; Liu, Tianming
2013-01-01
The human brain function involves complex processes with population codes of neuronal activities. Neuroscience research has demonstrated that when representing neuronal activities, sparsity is an important characterizing property. Inspired by this finding, significant amount of efforts from the scientific communities have been recently devoted to sparse representations of signals and patterns, and promising achievements have been made. However, sparse representation of fMRI signals, particularly at the population level of a group of different brains, has been rarely explored yet. In this paper, we present a novel group-wise sparse representation of task-based fMRI signals from multiple subjects via dictionary learning methods. Specifically, we extract and pool task-based fMRI signals for a set of cortical landmarks, each of which possesses intrinsic anatomical correspondence, from a group of subjects. Then an effective online dictionary learning algorithm is employed to learn an over-complete dictionary from the pooled population of fMRI signals based on optimally determined dictionary size. Our experiments have identified meaningful Atoms of Interests (AOI) in the learned dictionary, which correspond to consistent and meaningful functional responses of the brain to external stimulus. Our work demonstrated that sparse representation of group-wise fMRI signals is naturally suitable and effective in recovering population codes of neuronal signals conveyed in fMRI data.
MENTAL STATE REPRESENTATION: SPATIOTEMPORAL CHARACTERISTICS
Alexander Oktyabrinovich Prokhorov
2014-01-01
Full Text Available Since the time of statement of the problem of states in psychology, the study of “sensuous” tissue – the mental state representation-takes a fundamental meaning. The problem is concluded in the following questions: “How is mental state represented in the consciousness of an individual?”, “What is the specificity of the mental state representation as distinguished from the subject-matter representation?”, “What are the mechanisms of the mental state representation occurrence and the peculiarities of its dynamics? The study of the mental state representation will allow to explain its specificity and difference from the figurative representation, the peculiarities of state explication as a representation in the consciousness and its relation with other elements of consciousness, will allow to show the regularities of the mental state representation development and its dynamics, factors, which influence the specificity of its occurrence, the regulatory role of the state representation in the vital function. From these perspectives, the article presents the results of the study of spatiotemporal characteristics of the mental state representation; reveals the peculiar features of the spatiotemporal organization of mental state representations: Relieves, specificity, magnitude, variability of indicators, changes of structural characteristics in time spans; considers the age-specific peculiar features of the spatiotemporal organization of mental state representations in terms of organization, stability, coherence and differentiated nature of spatiotemporal structures with the representatives of certain age groups.
Schiffler, Ralf
2014-01-01
This book is intended to serve as a textbook for a course in Representation Theory of Algebras at the beginning graduate level. The text has two parts. In Part I, the theory is studied in an elementary way using quivers and their representations. This is a very hands-on approach and requires only basic knowledge of linear algebra. The main tool for describing the representation theory of a finite-dimensional algebra is its Auslander-Reiten quiver, and the text introduces these quivers as early as possible. Part II then uses the language of algebras and modules to build on the material developed before. The equivalence of the two approaches is proved in the text. The last chapter gives a proof of Gabriel’s Theorem. The language of category theory is developed along the way as needed.
Winskell, Kate; Obyerodhyambo, Oby; Stephenson, Rob
2011-01-01
Condoms are an essential component of comprehensive efforts to control the HIV epidemic, both for those who know their status and for those who do not. Although young people account for almost half of all new HIV infections, reported condom use among them remains low in many sub-Saharan African countries. In order to inform education and communication efforts to increase condom use, we examined social representations of condoms among young people aged 10–24 in six African countries/regions with diverse HIV prevalence rates: Swaziland, Namibia, Kenya, South-East Nigeria, Burkina Faso, and Senegal. We used a unique data source, namely 11,354 creative ideas contributed from these countries to a continent-wide scriptwriting contest, held from 1st February to 15th April 2005, on the theme of HIV/AIDS. We stratified each country sample by the sex, age (10–14, 15–19, 20–24), and urban/rural location of the author and randomly selected up to 10 narratives for each of the 12 resulting strata, netting a total sample of 586 texts for the six countries. We analyzed the narratives qualitatively using thematic data analysis and narrative-based methodologies. Differences were observed across settings in the prominence accorded to condoms, the assessment of their effectiveness, and certain barriers to and facilitators of their use. Moralization emerged as a key impediment to positive representations of condoms, while humour was an appealing means to normalize them. The social representations in the narratives identify communication needs in and across settings and provide youth-focused ideas and perspectives to inform future intervention efforts. PMID:21388731
Wulf-Andersen, Trine Østergaard
2012-01-01
This article is based on a Danish research project with young people in vulnerable positions. Young people are involved throughout the research process, including the interpretation of material produced through interviews, and discussions on how reflections and conclusions from the research should......, and dialogue, of situated participants. The article includes a lengthy example of a poetic representation of one participant’s story, and the author comments on the potentials of ‘doing’ poetic representations as an example of writing in ways that challenges what sometimes goes unasked in participative social...
Landi, Nicole; Perfetti, Charles A; Bolger, Donald J; Dunlap, Susan; Foorman, Barbara R
2006-06-01
To acquire representations of printed words, children must attend to the written form of a word and link this form with the word's pronunciation. When words are read in context, they may be read with less attention to these features, and this can lead to poorer word form retention. Two experiments with young children (ages 5-8 years) confirmed this hypothesis. In our experiments, children attempted to read words they could not previously read, during a self-teaching period, either in context or in isolation. Later they were tested on how well they learned the words as a function of self-teaching condition (isolation or context). Consistent with previous research, children read more words accurately in context than in isolation during self-teaching; however, children had better retention for words learned in isolation. Furthermore, this benefit from learning in isolation was larger for less skilled readers. This effect of poorer word retention when words are learned in context is paradoxical because context has been shown to facilitate word identification. We discuss factors that may influence this effect of context, especially the role of children's skill level and the demands of learning new word representations at the beginning of reading instruction.
Petersson, Dag; Dahlgren, Anna; Vestberg, Nina Lager
to the enterprises of the medium. This is the subject of Representational Machines: How photography enlists the workings of institutional technologies in search of establishing new iconic and social spaces. Together, the contributions to this edited volume span historical epochs, social environments, technological...
Silva, H G; Lopes, I
Heliospheric modulation of galactic cosmic rays links solar cycle activity with neutron monitor count rate on earth. A less direct relation holds between neutron monitor count rate and atmospheric electric field because different atmospheric processes, including fluctuations in the ionosphere, are involved. Although a full quantitative model is still lacking, this link is supported by solid statistical evidence. Thus, a connection between the solar cycle activity and atmospheric electric field is expected. To gain a deeper insight into these relations, sunspot area (NOAA, USA), neutron monitor count rate (Climax, Colorado, USA), and atmospheric electric field (Lisbon, Portugal) are presented here in a phase space representation. The period considered covers two solar cycles (21, 22) and extends from 1978 to 1990. Two solar maxima were observed in this dataset, one in 1979 and another in 1989, as well as one solar minimum in 1986. Two main observations of the present study were: (1) similar short-term topological features of the phase space representations of the three variables, (2) a long-term phase space radius synchronization between the solar cycle activity, neutron monitor count rate, and potential gradient (confirmed by absolute correlation values above ~0.8). Finally, the methodology proposed here can be used for obtaining the relations between other atmospheric parameters (e.g., solar radiation) and solar cycle activity.
Teachers’ representations of school indiscipline
Joe Garcia
2015-11-01
Full Text Available In this article we analyze a set of teachers’ representations of school indiscipline and its implications for pedagogical practices, particularly related to the resolution of problems in the classroom. Initially we explore three teachers’ representations on the genesis of school indiscipline. The first representation attributes prominence to the student as the singular subject in the production of indiscipline and who will be the center of the pedagogical intervention. The second representation attributes the genesis of the indiscipline to the context of the relations among the subjects in the classroom. The third representation suggests that the indiscipline would be something socially constructed in the schools, where it is intrinsically related to its nature and social function, and is an intrinsic part of its institutional culture. This third representation is distant of the previous ones, and provides an understanding of the indiscipline as a cultural message. In the second part of this article we analyze a set of implications of the teachers’ representations in relation to their pedagogical practices. At the ending of the text, we present some notes that put in evidence some issues that seems to be at the center in the study of the representations regarding to school indiscipline, in relation to the roles teachers are supposed to taken in contexts of indiscipline.
Xu, Jian; Fan, Engui
2017-02-01
In a previous work, we show that the solution of the initial-boundary value problem for the two-component nonlinear Schrödinger equation on the finite interval can be expressed in terms of the solution of a 3 ×3 Riemann-Hilbert problem. The relevant jump matrices are explicitly given in terms of the three matrix-value spectral functions s(k), S(k), and SL(k), which in turn are defined in terms of the initial values, boundary values at x = 0, and boundary values at x = L, respectively. However, for a well-posed problem, only part of the boundary values can be prescribed, the remaining boundary data cannot be independently specified but are determined by the so-called global relation. Here, we use a Gelfand-Levitan-Marchenko representation to derive an expression for the generalized Dirichlet-to-Neumann map to characterize the unknown boundary values in physical domain, which is different from the approach, in fact it analyzed the global relation in spectral domain, used in the previous work. And, we can show that these two representations are equivalent.
Tsuboi, Zengo
2012-01-01
We consider a class of asymptotic representations of the Borel subalgebra of the quantum affine superalgebra U_q(gl(M|N)^). This is characterized by Drinfeld rational fractions. In particular, we consider contractions of U_q(gl(M|N))in the FRT formulation and obtain explicit solutions of the graded Yang-Baxter equation in terms of q-oscillator superalgebras. These solutions correspond to L-operators for Baxter Q operators. We define model independent universal Q-operators as the supertrace of the universal R-matrix and write universal T-operators in terms of these Q-operators based on shift operators on the supercharacters. These include our previous work on U_q(sl(2|1)^) case [arXiv:0805.4274] in part, and also give a cue for operator realization of our Wronskian-like formulas on T-and Q-functions in [arXiv:0906.2039, arXiv:1109.5524].
Representation, interaction, and intersubjectivity.
Alterman, Richard
2007-09-10
What the participants share, their common "sense" of the world, creates a foundation, a framing, an orientation that enables human actors to see and act in coordination with one another. For recurrent activities, the methods the participants use to understand each other as they act change, making the intersubjective space in which actors operate richer and easier to produce. This article works through some of the issues that emerge from a close examination of intersubjectivity as it is managed through representation and interaction. The data that are presented document, in detail, a sequence of related interactions, within and across episodes of cooperation, where continuity and change can be observed. The emergence of conversational structure and coordinating representations are significant milestones in the long-term development of a representational practice that support the runtime co-construction of intersubjective space. Conversational structures emerge interactively to mediate recurrent points of coordination in the domain activity, and only secondarily the conversation itself. Coordinating representations change the representational practice of the participants by making it easier to manage their "shared view" of the collective work, enabling the participants to make progress, expand the field of the common activity, while exhibiting more control of if and when explicit grounding occurs.
$\\alpha$-Representation for QCD
Tuan, Richard Hong
1998-01-01
An $\\alpha$-parameter representation is derived for gauge field theories.It involves, relative to a scalar field theory, only constants and derivatives with respect to the $\\alpha$-parameters. Simple rules are given to obtain the $\\alpha$-representation for a Feynman graph with an arbitrary number of loops in gauge theories in the Feynman gauge.
Attitudes, social representations and social attitudes
Farr, Robert, M.
1994-01-01
This paper plays the role of the devil's advocate in relation to Colin Fraser's paper "attitudes, social representations and widespread beliefs". It argues for the alternative perspective which Colin identifies that social representations and social attitudes are epistemologically incompatible theories.
ZHAO SongNian; YAO Li; JIN Zhen; XIONG XiaoYun; WU Xia; ZOU Qi; YAO GuoZheng; CAI XiaoHong; LIU YiJun
2008-01-01
In fMRI experiments on object representation in visual cortex, we designed two types of stimuli: one is the gray face image and its line drawing, and the other is the illusion and its corresponding completed illusion. Both of them have the same global features with different minute details so that the results of fMRI experiments can be compared with each other. The first kind of visual stimuli was used in a block design fMRI experiment, and the second was used in an event-related fMRI experiment. Comparing and analyzing interesting visual cortex activity patterns and blood oxygenation level dependent (BOLD)-fMRI signal, we obtained results to show some invariance of global features of visual images. A plau-sible explanation about the invariant mechanism is related with the cooperation of synchronized re-sponse to the global features of the visual image with a feedback of shape perception from higher cortex to cortex V1, namely the integration of global features and embodiment of sparse representation and distributed population code.
Hossien Pourghassem
2011-04-01
Full Text Available Relevance feedback approaches is used to improve the performance of content-based image retrieval systems. In this paper, a novel relevance feedback approach based on similarity measure modification in an X-ray image retrieval system based on fuzzy representation using fuzzy attributed relational graph (FARG is presented. In this approach, optimum weight of each feature in feature vector is calculated using similarity rate between query image and relevant and irrelevant images in user feedback. The calculated weight is used to tune fuzzy graph matching algorithm as a modifier parameter in similarity measure. The standard deviation of the retrieved image features is applied to calculate the optimum weight. The proposed image retrieval system uses a FARG for representation of images, a fuzzy matching graph algorithm as similarity measure and a semantic classifier based on merging scheme for determination of the search space in image database. To evaluate relevance feedback approach in the proposed system, a standard X-ray image database consisting of 10000 images in 57 classes is used. The improvement of the evaluation parameters shows proficiency and efficiency of the proposed system.
Binamé, Florence; Danzio, Sophie; Poncelet, Martine
2015-11-01
Most research into orthographic learning abilities has been conducted in English with typically developing children using reading-based tasks. In the present study, we examined the abilities of French-speaking children with dyslexia to create novel orthographic representations for subsequent use in spelling and to maintain them in long-term memory. Their performance was compared with that of chronological age (CA)-matched and reading age (RA)-matched control children. We used an experimental task designed to provide optimal learning conditions (i.e. 10 spelling practice trials) ensuring the short-term acquisition of the spelling of the target orthographic word forms. After a 1-week delay, the long-term retention of the targets was assessed by a spelling post-test. Analysis of the results revealed that, in the short term, children with dyslexia learned the novel orthographic word forms well, only differing from both CA and RA controls on the initial decoding of the targets and from CA controls on the first two practice trials. In contrast, a dramatic drop was observed in their long-term retention relative to CA and RA controls. These results support the suggestion of the self-teaching hypothesis (Share, 1995) that initial errors in the decoding and spelling of unfamiliar words may hinder the establishment of fully specified novel orthographic representations.
Eve Benhamou
2014-08-01
Full Text Available As one of the most powerful purveyors of entertainment in the world, the Disney company has produced blockbuster films, including animated features that have enjoyed enduring popularity. Reflecting and shaping to some extent American popular culture and ideology, they have left vivid images in our memory. Arguably, one of Disney’s most ubiquitous symbol is the beautiful white princess. The representation of race relations in Disney films has always been problematic, sometimes sparking heated debates: non-white characters were either absent or stereotypically portrayed. Nonetheless, in parallel with the advent of multiculturalism in the 1990s, a series of films have foregrounded a new approach on these portrayals, the most notable being Pocahontas (1995, Atlantis (2001, and The Princess and the Frog (2009. In this article, I will examine the evolution of the representation of race, focusing on the film texts and their historical and cultural context, production history, and critical reception. I will argue that the apparent messages of tolerance and promotion of multiculturalism were accompanied and slowly replaced by a colour-blind erasure of race.
Gumerov, Nail A; O'Donovan, Adam E; Duraiswami, Ramani; Zotkin, Dmitry N
2010-01-01
The head-related transfer function (HRTF) is computed using the fast multipole accelerated boundary element method. For efficiency, the HRTF is computed using the reciprocity principle by placing a source at the ear and computing its field. Analysis is presented to modify the boundary value problem accordingly. To compute the HRTF corresponding to different ranges via a single computation, a compact and accurate representation of the HRTF, termed the spherical spectrum, is developed. Computations are reduced to a two stage process, the computation of the spherical spectrum and a subsequent evaluation of the HRTF. This representation allows easy interpolation and range extrapolation of HRTFs. HRTF computations are performed for the range of audible frequencies up to 20 kHz for several models including a sphere, human head models [the Neumann KU-100 ("Fritz") and the Knowles KEMAR ("Kemar") manikins], and head-and-torso model (the Kemar manikin). Comparisons between the different cases are provided. Comparisons with the computational data of other authors and available experimental data are conducted and show satisfactory agreement for the frequencies for which reliable experimental data are available. Results show that, given a good mesh, it is feasible to compute the HRTF over the full audible range on a regular personal computer.
Moore, C; Pure, K; Furrow, D
1990-06-01
2 experiments examined children's understanding of the expression of speaker certainty and uncertainty and its relation to their developing theory of mind. In the first experiment, 80 children between 3 and 6 years of age were presented with a task in which they had to guess the location of an object hidden in 1 of 2 boxes. As clues to location, the children were presented with contrasting pairs of statements by 2 puppets. Different trials contained all of the possible pairwise combinations of either the modal verbs must, might, and could or the modal adjuncts probably, possibly, and maybe. Results showed that while 3-year-olds did not differentiate between any of the modal contrasts presented, 4-year-olds and older children were able to find the hidden object on the basis of what they heard. Performance was best for contrasts involving a highly certain term (either must or probably) paired with a less certain term (might, could, possibly, and maybe). Experiment 2 was designed to determine whether competence with modal terms was related to competence with mental terms in the same task, and whether performance on the certainty task was related to other aspects of the child's understanding of the nature of beliefs. 26 4-year-olds were presented with the certainty task, involving both modal and mental terms, and with tasks assessing their understanding of false beliefs, representational change, and the appearance-reality distinction. Results showed that all of these tasks were intercorrelated, implying that what may develop at 4 years of age may be a general understanding of the representational nature of belief.
Rom, Eldad; Mikulincer, Mario
2003-06-01
Four studies examined attachment-style differences in group-related cognitions and behaviors. In Studies 1-2, participants completed scales on group-related cognitions and emotions. In Studies 3-4, participants were divided into small groups, and their performance in group tasks as well as the cohesion of their group were assessed. Both attachment anxiety and avoidance in close relationships were associated with negative group-related cognitions and emotions. Anxiety was also related to the pursuit of closeness goals and impaired instrumental performance in group tasks. Avoidance was related to the pursuit of distance goals and deficits in socioemotional and instrumental performance. Group cohesion significantly moderated the effects of attachment anxiety. The discussion emphasizes the relevance of attachment theory within group contexts.
Mullins, Michael
elements into the process of design. Through its immersive properties, virtual reality allows access to a spatial experience of a computer model very different to both screen based simulations as well as traditional forms of architectural representation. The dissertation focuses on processes of the current......Contemporary communicational and informational processes contribute to the shaping of our physical environment by having a powerful influence on the process of design. Applications of virtual reality (VR) are transforming the way architecture is conceived and produced by introducing dynamic...... by ‘professionals’ to ‘laypeople’. The thesis articulates problems in VR’s current application, specifically the CAVE and Panorama theatres, and seeks an understanding of how these problems may be addressed. The central questions that have motivated this research project are thus: What is architectural VR...
Bremner, J. Gavin; Batten, Annabel M.
Previous literature suggests that young children are relatively insensitive to viewpoint in drawing, only showing their view when the task demands it. In contrast, older children appear to become more sensitive to viewpoint, and it has been claimed that there is a developmental progression towards portrayal of viewpoint though linear perspective.…
Chicharro, Daniel
2014-06-01
The role of correlations between neuronal responses is crucial to understanding the neural code. A framework used to study this role comprises a breakdown of the mutual information between stimuli and responses into terms that aim to account for different coding modalities and the distinction between different notions of independence. Here we complete the list of types of independence and distinguish activity independence (related to total correlations), conditional independence (related to noise correlations), signal independence (related to signal correlations), coding independence (related to information transmission), and information independence (related to redundancy). For each type, we identify the probabilistic criterion that defines it, indicate the information-theoretic measure used as statistic to test for it, and provide a graphical criterion to recognize the causal configurations of stimuli and responses that lead to its existence. Using this causal analysis, we first provide sufficiency conditions relating these types. Second, we differentiate the use of the measures as statistics to test for the existence of independence from their use for quantification. We indicate that signal and noise correlation cannot be quantified separately. Third, we explicitly define alternative system configurations used to construct the measures, in which noise correlations or noise and signal correlations are eliminated. Accordingly, we examine which measures are meaningful only as a comparison across configurations and which ones provide a characterization of the actually observed responses without resorting to other configurations. Fourth, we compare the commonly used nonparametric approach to eliminate noise correlations with a functional (model-based) approach, showing that the former approach does not remove those effects of noise correlations captured by the tuning properties of the individual neurons, and implies nonlocal causal structure manipulations. These
Hellmuth, Marc; Stadler, Peter F.; Wieseke, Nicolas
2016-01-01
The concepts of orthology, paralogy, and xenology play a key role in molecular evolution. Orthology and paralogy distinguish whether a pair of genes originated by speciation or duplication. The corresponding binary relations on a set of genes form complementary cographs. Allowing more than two types of ancestral event types leads to symmetric symbolic ultrametrics. Horizontal gene transfer, which leads to xenologous gene pairs, however, is inherent asymmetric since one offspring copy "jumps" ...
Hellmuth, Marc; Stadler, Peter F; Wieseke, Nicolas
2017-07-01
The concepts of orthology, paralogy, and xenology play a key role in molecular evolution. Orthology and paralogy distinguish whether a pair of genes originated by speciation or duplication. The corresponding binary relations on a set of genes form complementary cographs. Allowing more than two types of ancestral event types leads to symmetric symbolic ultrametrics. Horizontal gene transfer, which leads to xenologous gene pairs, however, is inherent asymmetric since one offspring copy "jumps" into another genome, while the other continues to be inherited vertically. We therefore explore here the mathematical structure of the non-symmetric generalization of symbolic ultrametrics. Our main results tie non-symmetric ultrametrics together with di-cographs (the directed generalization of cographs), so-called uniformly non-prime ([Formula: see text]) 2-structures, and hierarchical structures on the set of strong modules. This yields a characterization of relation structures that can be explained in terms of trees and types of ancestral events. This framework accommodates a horizontal-transfer relation in terms of an ancestral event and thus, is slightly different from the the most commonly used definition of xenology. As a first step towards a practical use, we present a simple polynomial-time recognition algorithm of [Formula: see text] 2-structures and investigate the computational complexity of several types of editing problems for [Formula: see text] 2-structures. We show, finally that these NP-complete problems can be solved exactly as Integer Linear Programs.
Smith, Elliot H; Banks, Garrett P; Mikell, Charles B; Cash, Syndey S; Patel, Shaun R; Eskandar, Emad N; Sheth, Sameer A
2015-12-01
The feedback-related negativity (FRN) is a commonly observed potential in scalp electroencephalography (EEG) studies related to the valence of feedback about a subject's performance. This potential classically manifests as a negative deflection in medial frontocentral EEG contacts following negative feedback. Recent work has shown prominence of theta power in the spectral composition of the FRN, placing it within the larger class of "frontal midline theta" cognitive control signals. Although the dorsal anterior cingulate cortex (dACC) is thought to be the cortical generator of the FRN, conclusive data regarding its origin and propagation are lacking. Here we examine intracranial electrophysiology from the human medial and lateral prefrontal cortex (PFC) to better understand the anatomical localization and communication patterns of the FRN. We show that the FRN is evident in both low- and high-frequency local field potentials (LFPs) recorded on electrocorticography. The FRN is larger in medial compared with lateral PFC, and coupling between theta band phase and high-frequency LFP power is also greater in medial PFC. Using Granger causality and conditional mutual information analyses, we provide evidence that feedback-related information propagates from medial to lateral PFC, and that this information transfer oscillates with theta-range periodicity. These results provide evidence for the dACC as the cortical source of the FRN, provide insight into the local computation of frontal midline theta, and have implications for reinforcement learning models of cognitive control.
Haehnel, Melanie; Menzel, Randolf
2010-01-01
Gamma-aminobutyric acid immunoreactive feedback neurons of the protocerebral tract are a major component of the honeybee mushroom body. They have been shown to be subject to learning-related plasticity and provide putative inhibitory input to Kenyon cells and the pedunculus extrinsic neuron, PE1. We hypothesize, that learning-related modulation in these neurons is mediated by varying the amount of inhibition provided by feedback neurons. We performed Ca(2+) imaging recordings of populations of neurons of the protocerebral-calycal tract (PCT) while the bees were conditioned in an appetitive olfactory paradigm and their behavioral responses were quantified using electromyographic recordings from M17, the muscle which controls the proboscis extension response. The results corroborate findings from electrophysiological studies showing that PCT neurons respond to sucrose and odor stimuli. The odor responses are concentration dependent. Odor and sucrose responses are modulated by repeated stimulus presentations. Furthermore, animals that learned to associate an odor with sucrose reward responded to the repeated presentations of the rewarded odor with less depression than they did to an unrewarded and a control odor.
Park, Eun-Jung; Choi, Kyunghee
2013-01-01
In general, mathematical representations such as formulae, numbers, and graphs are the inseparable components in science used to better describe or explain scientific phenomena or knowledge. Regardless of their necessity and benefit, science seems to be difficult for some students, as a result of the mathematical representations and problem…
Multi-parameter Burau representations
Mohammad N. Abdulrahim; Madline Al- Tahan; Samer S. Habre
2013-01-01
We consider the multi-parameter representation of Artin's braid group introduced by D. D. Long and J. P. Tian, namely $\\alpha: B_{n}\\rightarrow GL_{m}(C)$, where $m=n!n$ . First, we show that there exists a complex specialization of the multi-parameter representation that does not arise from any Hecke algebra. Second, we find conditions under which the images of the generators of the braid group on three strings under the multi-parameter representation are unitary relative to a nonsingular he...
Thinking together with material representations
Stege Bjørndahl, Johanne; Fusaroli, Riccardo; Østergaard, Svend
2014-01-01
How do material representations such as models, diagrams and drawings come to shape and aid collective, epistemic processes? This study investigated how groups of participants spontaneously recruited material objects (in this case LEGO blocks) to support collective creative processes in the context......, the material representations were experimented on and physical attributes were explored resulting in discoveries of new meaning potentials and creative solutions. We discuss these different ways in which material representations do their work in collective reasoning processes in relation to ideas about top...
李松; 张丽平; 郝晓红; 郝忠孝
2015-01-01
Vague区域关系和Vague方向关系的表示和推理在空间数据库、网络信息安全、数据挖掘和人工智能等领域具有重要的意义。为了处理复杂的Vague区域关系和Vague方向关系表示及其复合推理等问题，基于Vague集对Vague区域关系和方向关系进行了系统研究。给出了Vague区域关系交集矩阵和表示模型；为了处理由参照对象的不确定性所导致的方向关系的不确定性，基于V ag ue集提出了V ag ue方向关系的交集矩阵表示方法；为了对动态V ag ue方向关系进行分析、预测与推理，详细研究了Vague方向关系的动态性和动态邻接关系，给出了Vague方向关系的反向方向关系处理方法；进一步研究了Vague区域关系和Vague方向关系的复合关联推理方法。理论研究和实验分析表明研究成果可较好地处理V ag ue区域关系和V ag ue方向关系及其复合关联推理等问题，增强了数据信息处理系统对复杂不确定空间关系的处理能力。%Representation and reasoning of Vague region relations and direction relations have important significance in spatial database ,network information security ,data mining and artificial intelligence ,etc . To deal with the complex representations and the compound reasoning of Vague region relations and direction relations , Vague region relations and direction relations are systematically analyzed based on the Vague sets which can deal with a great deal of uncertainty information .Based on the Vague sets ,the intersection matrices and the representation model of the Vague regions are given .To handle the uncertainty of the direction relations caused by the ambiguity of Vague regions ,Vague direction points and Vague direction space are defined based on the Vague sets and the intersection matrices of the direction relations are studied .To analyze and reason the dynamic Vague direction relations , the dynamic adjacency table of the Vague
ZHU Li-jin; JIANG Yi-guo
2005-01-01
Objective: To analyze the differentially expressed cDNA sequences related to chlorophyllin (CHL) mediated inhibition of malignant transformation of human bronchia1 epithelial cell line (16HBE). Methods: 16HBE cells treated with chlorophyllin and anti-BPDE were conducted as tester, 16HBE cells treated only with anti-BPDE were conducted as driver, and cDNA representational difference analysis (cDNA RDA) was used to compare the differential gene expression between the two kinds of cells. The cDNA fragments were ligated to pGEM-T vector and transformed into JM109 bacteria. The plasmid DNA was sequenced and compared with database in GenBank by BLASTN. Results: Among the 5 cloned cDNA sequences, three were novel and were registered in dbEST database, two showed sequence homology to alpha-enolase and a newly found gene ribosomal protein S18/S6-like. Conclusion: These 5 cDNA sequences might play important roles in antitransforming effect of chlorophyllin.
On Representation in Information Theory
Joseph E. Brenner
2011-09-01
Full Text Available Semiotics is widely applied in theories of information. Following the original triadic characterization of reality by Peirce, the linguistic processes involved in information—production, transmission, reception, and understanding—would all appear to be interpretable in terms of signs and their relations to their objects. Perhaps the most important of these relations is that of the representation-one, entity, standing for or representing some other. For example, an index—one of the three major kinds of signs—is said to represent something by being directly related to its object. My position, however, is that the concept of symbolic representations having such roles in information, as intermediaries, is fraught with the same difficulties as in representational theories of mind. I have proposed an extension of logic to complex real phenomena, including mind and information (Logic in Reality; LIR, most recently at the 4th International Conference on the Foundations of Information Science (Beijing, August, 2010. LIR provides explanations for the evolution of complex processes, including information, that do not require any entities other than the processes themselves. In this paper, I discuss the limitations of the standard relation of representation. I argue that more realistic pictures of informational systems can be provided by reference to information as an energetic process, following the categorial ontology of LIR. This approach enables naïve, anti-realist conceptions of anti-representationalism to be avoided, and enables an approach to both information and meaning in the same novel logical framework.
Residual Representations of Spacetime
Saller, H
2001-01-01
Spacetime is modelled by binary relations - by the classes of the automorphisms $\\GL(\\C^2)$ of a complex 2-dimensional vector space with respect to the definite unitary subgroup $\\U(2)$. In extension of Feynman propagators for particle quantum fields representing only the tangent spacetime structure, global spacetime representations are given, formulated as residues using energy-momentum distributions with the invariants as singularities. The associatated quantum fields are characterized by two invariant masses - for time and position - supplementing the one mass for the definite unitary particle sector with another mass for the indefinite unitary interaction sector without asymptotic particle interpretation.
[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
Furman, Wyndol; Collibee, Charlene
2016-12-28
This study examined how representations of parent-child relationships, friendships, and past romantic relationships are related to subsequent romantic representations. Two-hundred 10th graders (100 female; Mage = 15.87 years) from diverse neighborhoods in a Western U.S. city were administered questionnaires and were interviewed to assess avoidant and anxious representations of their relationships with parents, friends, and romantic partners. Participants then completed similar questionnaires and interviews about their romantic representations six more times over the next 7.5 years. Growth curve analyses revealed that representations of relationships with parents, friends, and romantic partners each uniquely predicted subsequent romantic representations across development. Consistent with attachment and behavioral systems theory, representations of romantic relationships are revised by representations and experiences in other relationships.
Representation as the representation of experience
Ankersmit, FR
This essay deals, mainly, with the notion of representation. Representation is associated with texts and, as such, is contrasted to the true singular statement. It is argued that the relationship between the text and what the text represents can never be modeled on the relationship between the true
Klein Topological Field Theories from Group Representations
Sergey A. Loktev
2011-07-01
Full Text Available We show that any complex (respectively real representation of finite group naturally generates a open-closed (respectively Klein topological field theory over complex numbers. We relate the 1-point correlator for the projective plane in this theory with the Frobenius-Schur indicator on the representation. We relate any complex simple Klein TFT to a real division ring.
22 CFR 18.13 - Representation.
2010-04-01
... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Representation. 18.13 Section 18.13 Foreign Relations DEPARTMENT OF STATE PERSONNEL REGULATIONS CONCERNING POST EMPLOYMENT CONFLICT OF INTEREST Administrative Enforcement Proceedings § 18.13 Representation. A respondent or proposed respondent may appear in...
Social Representations of Intelligence
Elena Zubieta
2016-02-01
Full Text Available The article stresses the relationship between Explicit and Implicit theories of Intelligence. Following the line of common sense epistemology and the theory of Social Representations, a study was carried out in order to analyze naive’s explanations about Intelligence Definitions. Based on Mugny & Carugati (1989 research, a self-administered questionnaire was designed and filled in by 286 subjects. Results are congruent with the main hyphotesis postulated: A general overlap between explicit and implicit theories showed up. According to the results Intelligence appears as both, a social attribute related to social adaptation and as a concept defined in relation with contextual variables similar to expert’s current discourses. Nevertheless, conceptions based on “gifted ideology” still are present stressing the main axes of Intelligence debate: biological and sociological determinism. In the same sense, unfamiliarity and social identity are reaffirmed as organizing principles of social representation. The distance with the object -measured as the belief in intelligence differences as a solve/non solve problem- and the level of implication with the topic -teachers/no teachers- appear as discriminating elements at the moment of supporting specific dimensions.
Nouwen, Arie; Urquhart Law, G; Hussain, Shakir; McGovern, Steven; Napier, Heidi
2009-11-01
This cross-sectional study examined the joint effects of self-efficacy and illness representations on dietary self-care and diabetes distress in adolescents with type 1 diabetes by comparing two theoretical models: the Self-regulation Model (Leventhal, H., Meyer, D., & Nerenz, D. (1980). The common-sense representations of illness danger. In S. Rachman (Ed.), Medical Psychology (Vol. 2, pp. 7-30). New York: Pergamon.) and Social Cognitive Theory (Bandura, A. (1997). Self efficacy: The exercise of control. New York: W.H. Freeman.). One hundred and fifty-one adolescents with type 1 diabetes completed self-report measures of dietary self-efficacy, illness representations, dietary self-care and diabetes distress. Data were analysed using structural equation modelling. The model best supported by the data (Leventhal's Self-regulation Model) showed that dietary self-efficacy, perceived consequences and treatment effectiveness had direct and independent effects on both dietary self-care and diabetes distress. Together with dietary self-efficacy, perceived short-term treatment effectiveness was a significant predictor of dietary self-care. Age was found to be a negative predictor of short-term treatment effectiveness beliefs. Diabetes distress was best predicted by self-efficacy and perceived consequences. It can be concluded that to target effectively dietary self-care and distress, clinicians should focus on key illness representation variables (perceived short-term treatment effectiveness and perceived consequences) in conjunction with self-efficacy.
Digital models for architectonical representation
Stefano Brusaporci
2011-12-01
Full Text Available Digital instruments and technologies enrich architectonical representation and communication opportunities. Computer graphics is organized according the two phases of visualization and construction, that is modeling and rendering, structuring dichotomy of software technologies. Visualization modalities give different kinds of representations of the same 3D model and instruments produce a separation between drawing and image’s creation. Reverse modeling can be related to a synthesis process, ‘direct modeling’ follows an analytic procedure. The difference between interactive and not interactive applications is connected to the possibilities offered by informatics instruments, and relates to modeling and rendering. At the same time the word ‘model’ describes different phenomenon (i.e. files: mathematical model of the building and of the scene; raster representation and post-processing model. All these correlated different models constitute the architectonical interpretative model, that is a simulation of reality made by the model for improving the knowledge.
Building Hierarchical Representations for Oracle Character and Sketch Recognition.
Jun Guo; Changhu Wang; Roman-Rangel, Edgar; Hongyang Chao; Yong Rui
2016-01-01
In this paper, we study oracle character recognition and general sketch recognition. First, a data set of oracle characters, which are the oldest hieroglyphs in China yet remain a part of modern Chinese characters, is collected for analysis. Second, typical visual representations in shape- and sketch-related works are evaluated. We analyze the problems suffered when addressing these representations and determine several representation design criteria. Based on the analysis, we propose a novel hierarchical representation that combines a Gabor-related low-level representation and a sparse-encoder-related mid-level representation. Extensive experiments show the effectiveness of the proposed representation in both oracle character recognition and general sketch recognition. The proposed representation is also complementary to convolutional neural network (CNN)-based models. We introduce a solution to combine the proposed representation with CNN-based models, and achieve better performances over both approaches. This solution has beaten humans at recognizing general sketches.
Neural representation of behavioral outcomes in the orbitofrontal cortex.
Mainen, Zachary F; Kepecs, Adam
2009-02-01
The orbitofrontal cortex (OFC) is important in processing rewards and other behavioral outcomes. Here, we review from a computational perspective recent progress in understanding this complex function. OFC neurons appear to represent abstract outcome values, which may facilitate the comparison of options, as well as concrete outcome attributes, such as flavor or location, which may enable predictive cues to access current outcome values in the face of dynamic modulation by internal state, context and learning. OFC can use reinforcement learning to generate outcome predictions; it can also generate outcome predictions using other mechanisms, including the evaluation of decision confidence or uncertainty. OFC neurons encode not only the mean expected outcome but also the variance, consistent with the idea that OFC uses a probabilistic population code to represent outcomes. We suggest that further attention to the nature of its representations and algorithms will be critical to further elucidating OFC function.
Daniela Rabellino
2016-11-01
Full Text Available Background: Early traumatic experiences are thought to be causal factors in the development of trauma-related dissociative experiences, including depersonalization and derealization. The rubber hand illusion (RHI, a well-known paradigm that measures multi-sensorial integration of a rubber hand into one's own body representation, has been used to investigate alterations in the experience of body ownership and of body representation. Critically, however, it has never been studied in individuals with trauma-related disorders. Objective: To investigate body representation distortions occurring in trauma-related disorders in response to the RHI. Method: The RHI was administered to three individuals with the dissociative subtype of posttraumatic stress disorder (PTSD, and subjective, behavioral, cardiovascular and skin conductance responses were recorded. Results: Participants’ subjective experiences of the RHI were differentiated and complex. The illusion was induced following both synchronous and asynchronous brushing and variably evoked subjective distress, depersonalization and derealization experiences, tonic immobility, increased physiological arousal and flashbacks. Conclusions: The present findings point towards the RHI as a strong provocation stimulus that elicits individual patterns of symptom presentation, including experiences of distress and dissociation, in individuals with trauma-related disorders, including the dissociative subtype of PTSD. Highlights of the article:
Integrality of representations of finite groups
Hofmann, Tommy
2016-01-01
Since the early days of representation theory of finite groups in the 19th century, it was known that complex linear representations of finite groups live over number fields, that is, over finite extensions of the field of rational numbers. While the related question of integrality of representations was answered negatively by the work of Cliff, Ritter and Weiss as well as by Serre and Feit, it was not known how to decide integrality of a given representation. In this thesis we show tha...
Digital Image Representation and Access.
Mostafa, Javed
1994-01-01
Reviews the literature relating to the development and application of modern imaging technology between 1987 and 1993. Highlights include image representation, including image data, compression, and image formats; and image access, including indexing and modeling, user interface design, and distributed access. (143 references) (LRW)
Self-Representation and Brain Development
Lewis, Michael; Carmody, Dennis P.
2008-01-01
This study examined the relation between self-representation and brain development in infants and young children. Self-representation was assessed by mirror recognition, personal pronoun use, and pretend play. Structural brain images were obtained from magnetic resonance imaging (MRI). Brain development was assessed by a quantitative measure of…
Student Teachers' Knowledge about Chemical Representations
Taskin, Vahide; Bernholt, Sascha; Parchmann, Ilka
2017-01-01
Chemical representations serve as a communication tool not only in exchanges between scientists but also in chemistry lessons. The goals of the present study were to measure the extent of student teachers' knowledge about chemical representations, focusing on chemical formulae and structures in particular, and to explore which factors related to…
An Axiomatic Representation of System Dynamics
Baianu, I
2004-01-01
An axiomatic representation of system dynamics is introduced in terms of categories, functors, organismal supercategories, limits and colimits of diagrams. Specific examples are considered in Complex Systems Biology, such as ribosome biogenesis and Hormonal Control in human subjects. "Fuzzy" Relational Structures are also proposed for flexible representations of biological system dynamics and organization.
29 CFR 1202.3 - Representation disputes.
2010-07-01
... 29 Labor 4 2010-07-01 2010-07-01 false Representation disputes. 1202.3 Section 1202.3 Labor Regulations Relating to Labor (Continued) NATIONAL MEDIATION BOARD RULES OF PROCEDURE § 1202.3 Representation disputes. If any dispute shall arise among a carrier's employees as to who are the representatives of such...
15 CFR 766.4 - Representation.
2010-01-01
... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Representation. 766.4 Section 766.4 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF... PROCEEDINGS § 766.4 Representation. A respondent individual may appear and participate in person, a...
15 CFR 785.5 - Representation.
2010-01-01
... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Representation. 785.5 Section 785.5 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF... Representation. An individual respondent may appear, in person, or be represented by a duly authorized officer or...
45 CFR 1225.5 - Representation.
2010-10-01
... 45 Public Welfare 4 2010-10-01 2010-10-01 false Representation. 1225.5 Section 1225.5 Public Welfare Regulations Relating to Public Welfare (Continued) CORPORATION FOR NATIONAL AND COMMUNITY SERVICE VOLUNTEER DISCRIMINATION COMPLAINT PROCEDURE General Provisions § 1225.5 Representation. Any aggrieved party...
15 CFR 90.18 - Representation.
2010-01-01
... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Representation. 90.18 Section 90.18 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade BUREAU OF THE CENSUS... Representation. A challenging unit of government may be represented by its chief executive officer or by counsel...
15 CFR 280.205 - Representation.
2010-01-01
... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Representation. 280.205 Section 280.205 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade NATIONAL INSTITUTE... QUALITY Enforcement § 280.205 Representation. A respondent individual may appear and participate in person...
15 CFR 719.7 - Representation.
2010-01-01
... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Representation. 719.7 Section 719.7 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF... Representation. A respondent individual may appear and participate in person, a corporation by a duly authorized...
Rabellino, Daniela; Harricharan, Sherain; Frewen, Paul A.; Burin, Dalila; McKinnon, Margaret C.; Lanius, Ruth A.
2016-01-01
Background Early traumatic experiences are thought to be causal factors in the development of trauma-related dissociative experiences, including depersonalization and derealization. The rubber hand illusion (RHI), a well-known paradigm that measures multi-sensorial integration of a rubber hand into one’s own body representation, has been used to investigate alterations in the experience of body ownership and of body representation. Critically, however, it has never been studied in individuals with trauma-related disorders. Objective To investigate body representation distortions occurring in trauma-related disorders in response to the RHI. Method The RHI was administered to three individuals with the dissociative subtype of posttraumatic stress disorder (PTSD), and subjective, behavioral, cardiovascular and skin conductance responses were recorded. Results Participants’ subjective experiences of the RHI were differentiated and complex. The illusion was induced following both synchronous and asynchronous brushing and variably evoked subjective distress, depersonalization and derealization experiences, tonic immobility, increased physiological arousal and flashbacks. Conclusions The present findings point towards the RHI as a strong provocation stimulus that elicits individual patterns of symptom presentation, including experiences of distress and dissociation, in individuals with trauma-related disorders, including the dissociative subtype of PTSD. Highlights of the article The rubber hand illusion (RHI) elicits distress, tonic immobility, depersonalization and derealization, and autonomic responses in individuals with trauma-related disorders, including the dissociative subtype of posttraumatic stress disorder (PTSD). RHI effects related to body misrepresentation may trigger altered experiences related to body ownership. The RHI represents a promising paradigm for studying the neurophenomenology of body distortion in individuals experiencing trauma-related
Intentionality, Representation, and Anticipation
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.
Marielle Salvador-Perignon
2011-09-01
Full Text Available Cette recherche se propose d’aborder le mode de production du produit alimentaire sous l’angle des représentations mentales en France. Dans le langage commun on entend souvent les termes « industriel » ou « artisanal » pour caractériser les produits alimentaires, sans que l’on sache vraiment ce que ces termes désignent. Le contexte actuel d’incertitude et de méconnaissance des systèmes de production chez les consommateurs nous permet d’émettre l’hypothèse de l’existence d’une représentation mentale du mode de production. Nous tentons de vérifier cette hypothèse par une étude qualitative à l’issue de laquelle les premières caractéristiques du produit alimentaire industriel ou artisanal sont précisées.This research approaches the food product through the mental representations concerning manufacturing processes. In the common language we often find such terms as “industrial” or “traditional” to qualify production methods and characterize food products, but do we know what these terms really mean? Uncertainties and misunderstandings regarding food production enable us to highlight the existence of consumers’ mental representations regarding manufacturing processes. Such representations have been studied by means of a qualitative study which enabled us to define the primary characteristics of industrial or traditional food products.
Social representations of women
Álvaro Estramiana, José Luis
2006-05-01
Full Text Available Social Representations is one of the most important theories in contemporary social psychology. Since the social psychologist Serge Moscovici developed his theory of social representations to explain how a scientific theory such as the psychoanalysis turns into a common sense knowledge many studies have been done by different social psychologists. The analysis of the social representations of women as represented in myths and popular beliefs is an excellent opportunity to study how this theory can be applied to this representational field. At the same time it makes possible to understand the formation of attitudes towards women
Peuquet, Donna J.
1987-01-01
A new approach to building geographic data models that is based on the fundamental characteristics of the data is presented. An overall theoretical framework for representing geographic data is proposed. An example of utilizing this framework in a Geographic Information System (GIS) context by combining artificial intelligence techniques with recent developments in spatial data processing techniques is given. Elements of data representation discussed include hierarchical structure, separation of locational and conceptual views, and the ability to store knowledge at variable levels of completeness and precision.
Extensions of tempered representations
Opdam, E.; Solleveld, M.
2013-01-01
Let π, π′ be irreducible tempered representations of an affine Hecke algebra H with positive parameters. We compute the higher extension groups Ext nH(π,π′) explicitly in terms of the representations of analytic R-groups corresponding to π and π′. The result has immediate applications to the computa
Multiple sparse representations classification
E. Plenge (Esben); S.K. Klein (Stefan); W.J. Niessen (Wiro); E. Meijering (Erik)
2015-01-01
textabstractSparse representations classification (SRC) is a powerful technique for pixelwise classification of images and it is increasingly being used for a wide variety of image analysis tasks. The method uses sparse representation and learned redundant dictionaries to classify image pixels. In t
Embedded Data Representations.
Willett, Wesley; Jansen, Yvonne; Dragicevic, Pierre
2017-01-01
We introduce embedded data representations, the use of visual and physical representations of data that are deeply integrated with the physical spaces, objects, and entities to which the data refers. Technologies like lightweight wireless displays, mixed reality hardware, and autonomous vehicles are making it increasingly easier to display data in-context. While researchers and artists have already begun to create embedded data representations, the benefits, trade-offs, and even the language necessary to describe and compare these approaches remain unexplored. In this paper, we formalize the notion of physical data referents - the real-world entities and spaces to which data corresponds - and examine the relationship between referents and the visual and physical representations of their data. We differentiate situated representations, which display data in proximity to data referents, and embedded representations, which display data so that it spatially coincides with data referents. Drawing on examples from visualization, ubiquitous computing, and art, we explore the role of spatial indirection, scale, and interaction for embedded representations. We also examine the tradeoffs between non-situated, situated, and embedded data displays, including both visualizations and physicalizations. Based on our observations, we identify a variety of design challenges for embedded data representation, and suggest opportunities for future research and applications.
Ankersmit, F.R.
2010-01-01
This essay focuses on the historical text as a whole. It does so by conceiving of the historical text as representation - in the way the we may say of a photo or a painting that it represents the person depicted on it. It is argued that representation cannot be properly understood by modelling it on
Group and representation theory
Vergados, J D
2017-01-01
This volume goes beyond the understanding of symmetries and exploits them in the study of the behavior of both classical and quantum physical systems. Thus it is important to study the symmetries described by continuous (Lie) groups of transformations. We then discuss how we get operators that form a Lie algebra. Of particular interest to physics is the representation of the elements of the algebra and the group in terms of matrices and, in particular, the irreducible representations. These representations can be identified with physical observables. This leads to the study of the classical Lie algebras, associated with unitary, unimodular, orthogonal and symplectic transformations. We also discuss some special algebras in some detail. The discussion proceeds along the lines of the Cartan-Weyl theory via the root vectors and root diagrams and, in particular, the Dynkin representation of the roots. Thus the representations are expressed in terms of weights, which are generated by the application of the elemen...
Willett, Wesley; Jansen, Yvonne; Dragicevic, Pierre
2017-01-01
We introduce embedded data representations, the use of visual and physical representations of data that are deeply integrated with the physical spaces, objects, and entities to which the data refers. Technologies like lightweight wireless displays, mixed reality hardware, and autonomous vehicles...... are making it increasingly easier to display data in-context. While researchers and artists have already begun to create embedded data representations, the benefits, trade-offs, and even the language necessary to describe and compare these approaches remain unexplored. In this paper, we formalize the notion...... of physical data referents – the real-world entities and spaces to which data corresponds – and examine the relationship between referents and the visual and physical representations of their data. We differentiate situated representations, which display data in proximity to data referents, and embedded...
Scientific Representation and Nominalism: An Empiricist View
Otávio Bueno
2008-12-01
Full Text Available Can a constructive empiricist make sense of scientific representation? Usually, a scientific model is an abstract entity (e.g., formulated in set theory, and scientific representation is conceptualized as an intentional relation between scientific models and certain aspects of the world. On this conception, since both the models and the representation relation are abstract, a constructive empiricist, who is not committed to the existence of abstract entities, would be unable to invoke these notions to make sense of scientific representation. In this paper, instead of understanding representation as a relation between abstract entities, I focus on the activity of representing, and argue that it provides a way of making sense of representation within the boundaries of empiricism. The activity of representing doesn’t deal with abstract entities, but with concrete ones, such as inscriptions, templates, and blueprints. In the end, by examining the practice of representing, rather than an artificially reified product—the representation—the constructive empiricist has the resources to make sense of scientific representation in empiricist terms.
STUDY ON THE REPRESENTATION OF THE PLÜCKER CONOID
DRAGAN Delia
2008-07-01
Full Text Available The architecture and construction related design requires an in-depth knowledge of all the systems of representation of solids and surfaces. This paper presents a comparative study on the representation of the Plücker conoid using the three systems of representation, i.e. axonometry, the orthogonal projection on two planes of projection and the projection with elevation. Each of these representation systems has its own advantages and disadvantages. They relate to the practical aspect of measuring the true lengths, respectively sizes of angles and surfaces. Then, the way in which the representation is perceived spatially by specialists or non-specialists is also of importance.
Distinguishing Representations as Origin and Representations as Input: Roles for Individual Neurons
Edwards, Jonathan C. W.
2016-01-01
in an input interaction between signals and consumer. The acceptance of this necessity provides a basis for resolving the problem that representations appear both as distributed (representation-as-origin) and as local (representation-as-input). The key implications are that representations in the brain are massively multiple both in series and in parallel, and that individual cells play specific semantic roles. These roles are discussed in relation to traditional concepts of ‘gnostic’ cell types. PMID:27746760
Distinguishing Representations as Origin and Representations as Input: Roles for Individual Cells
Jonathan C.W. Edwards
2016-09-01
input interaction between signals and consumer. The acceptance of this necessity provides a basis for resolving the problem that representations appear both as distributed (representation-as-origin and local (representation-as-input. The key implications are that representations in brain are massively multiple both in series and in parallel, and that individual cells play specific semantic roles. These roles are discussed in relation to traditional concepts of ‘gnostic’ cell types.
Hyperfinite Representation of Distributions
J Sousa Pinto; R F Hoskins
2000-11-01
Hyperfinite representation of distributions is studied following the method introduced by Kinoshita [2, 3], although we use a different approach much in the vein of [4]. Products and Fourier transforms of representatives of distributions are also analysed.
Income, Ideology, and Representation
Chris Tausanovitch
2016-11-01
Full Text Available Do legislators represent the rich better than they represent the poor? Recent work provides mixed support for this proposition. I test the hypothesis of differential representation using a data set on the political preferences of 318,537 individuals. Evidence of differential representation in the House of Representatives is weak. Support for differential representation is stronger in the Senate. In recent years, representation has occurred primarily through the selection of a legislator from the appropriate party. Although the preferences of higher-income constituents account for more of the variation in legislator voting behavior, higher-income constituents also account for much more of the variation in district preferences. In light of the low level of overall responsiveness, differential responsiveness appears small.
Ordering ambiguity versus representation
Souza de Dutra, A [Abdus Salam ICTP, Strada Costiera 11, 34014 Trieste (Italy); UNESP-Campus de Guaratingueta-DFQ , Av. Dr. Ariberto Pereira da Cunha, 333, C.P. 205, 12516-410 Guaratingueta SP (Brazil)
2006-01-06
In this work we show that the ordering ambiguity on quantization depends on the representation choice. This property is then used to solve unambiguously some particular systems. Finally, we speculate on the consequences for more involved cases.
MORPHOLOGICAL REPRESENTATION AND SEMANTIC ...
The morphological representation assigned to a complex word must provide the formal structure .... This brings us to the cases where, on Williams's (1981a:258) analysis, the compositional notion ...... Die en moda Ii tei t . Kaaps tad: Ba 1 kema.
Gao, Jie; Xu, Zhen-Yuan
2009-01-01
Chaos game representation (CGR) is an iterative mapping technique that processes sequences of units, such as nucleotides in a DNA sequence or amino acids in a protein, in order to determine the coordinates of their positions in a continuous space. This distribution of positions has two features: one is unique, and the other is source sequence that can be recovered from the coordinates so that the distance between positions may serve as a measure of similarity between the corresponding sequences. A CGR-walk model is proposed based on CGR coordinates for the DNA sequences. The CGR coordinates are converted into a time series, and a long-memory ARFIMA (p, d, q) model, where ARFIMA stands for autoregressive fractionally integrated moving average, is introduced into the DNA sequence analysis. This model is applied to simulating real CGR-walk sequence data of ten genomic sequences. Remarkably long-range correlations are uncovered in the data, and the results from these models are reasonably fitted with those from the ARFIMA (p, d, q) model.
Function, anticipation, representation
Bickhard, Mark. H.
2001-06-01
Function emerges in certain kinds of far-from-equilibrium systems. One important kind of function is that of interactive anticipation, an adaptedness to temporal complexity. Interactive anticipation is the locus of the emergence of normative representational content, and, thus, of representation in general: interactive anticipation is the naturalistic core of the evolution of cognition. Higher forms of such anticipation are involved in the subsequent macro-evolutionary sequence of learning, emotions, and reflexive consciousness.
Updating collection representations for federated search
M. Shokouhi; Baillie, M; Azzopardi, L.
2007-01-01
To facilitate the search for relevant information across a set of online distributed collections, a federated information retrieval system typically represents each collection, centrally, by a set of vocabularies or sampled documents. Accurate retrieval is therefore related to how precise each representation reflects the underlying content stored in that collection. As collections evolve over time, collection representations should also be updated to reflect any change, however, a current sol...
Multipolar representation of protein structure
Bourne Philip E
2006-05-01
Full Text Available Abstract Background That the structure determines the function of proteins is a central paradigm in biology. However, protein functions are more directly related to cooperative effects at the residue and multi-residue scales. As such, current representations based on atomic coordinates can be considered inadequate. Bridging the gap between atomic-level structure and overall protein-level functionality requires parameterizations of the protein structure (and other physicochemical properties in a quasi-continuous range, from a simple collection of unrelated amino acids coordinates to the highly synergistic organization of the whole protein entity, from a microscopic view in which each atom is completely resolved to a "macroscopic" description such as the one encoded in the three-dimensional protein shape. Results Here we propose such a parameterization and study its relationship to the standard Euclidian description based on amino acid representative coordinates. The representation uses multipoles associated with residue Cα coordinates as shape descriptors. We demonstrate that the multipoles can be used for the quantitative description of the protein shape and for the comparison of protein structures at various levels of detail. Specifically, we construct a (dissimilarity measure in multipolar configuration space, and show how such a function can be used for the comparison of a pair of proteins. We then test the parameterization on a benchmark set of the protein kinase-like superfamily. We prove that, when the biologically relevant portions of the proteins are retained, it can robustly discriminate between the various families in the set in a way not possible through sequence or conventional structural representations alone. We then compare our representation with the Cartesian coordinate description and show that, as expected, the correlation with that representation increases as the level of detail, measured by the highest rank of multipoles
Efficient visual tracking via low-complexity sparse representation
Lu, Weizhi; Zhang, Jinglin; Kpalma, Kidiyo; Ronsin, Joseph
2015-12-01
Thanks to its good performance on object recognition, sparse representation has recently been widely studied in the area of visual object tracking. Up to now, little attention has been paid to the complexity of sparse representation, while most works are focused on the performance improvement. By reducing the computation load related to sparse representation hundreds of times, this paper proposes by far the most computationally efficient tracking approach based on sparse representation. The proposal simply consists of two stages of sparse representation, one is for object detection and the other for object validation. Experimentally, it achieves better performance than some state-of-the-art methods in both accuracy and speed.
Neural Representations of Physics Concepts.
Mason, Robert A; Just, Marcel Adam
2016-06-01
We used functional MRI (fMRI) to assess neural representations of physics concepts (momentum, energy, etc.) in juniors, seniors, and graduate students majoring in physics or engineering. Our goal was to identify the underlying neural dimensions of these representations. Using factor analysis to reduce the number of dimensions of activation, we obtained four physics-related factors that were mapped to sets of voxels. The four factors were interpretable as causal motion visualization, periodicity, algebraic form, and energy flow. The individual concepts were identifiable from their fMRI signatures with a mean rank accuracy of .75 using a machine-learning (multivoxel) classifier. Furthermore, there was commonality in participants' neural representation of physics; a classifier trained on data from all but one participant identified the concepts in the left-out participant (mean accuracy = .71 across all nine participant samples). The findings indicate that abstract scientific concepts acquired in an educational setting evoke activation patterns that are identifiable and common, indicating that science education builds abstract knowledge using inherent, repurposed brain systems.
On Performance Skill Representation Framework
Furukawa, Koichi; Shimizu, Satoshi; Yoshinaga, Saori
In this paper, we propose a framework for representing performance skill. Firstly, we notice the importance of performance skill representation. We introduce five different representation targets: performance tasks, performance rules, pre-shaping actions, dynamic integrity constraints, and performance states. Performance task description consists of a sequence of performance tasks and expressions. It acts as a goal description in planning. Performance rules describe model performance methods for given tasks including how to shape body parts and how to use various muscles. Pre-shaping action rules are similar to performance rules. Its role is to pre-shape in between consecutive tasks to prepare for the next task. Dynamic integrity constraints specify constraints to be satisfied during performance. They provide such general rules as prohibiting simultaneous strong activations of agonist and antagonist. Performance states are for describing real performance done by players including professionals and amateurs. The aim of the framework is to provide a uniform scheme for representing model performance methods given performance score such as music score. The representation framework will define targets of inducing formal skill rules as well as describing performance states automatically from biomechanical performance data. It also is related to a fundamental research issue of attributes finding/selection in discovering useful rules for skillful performance. We conclude our paper by stating future research direction.
Representation Elements of Spatial Thinking
Fiantika, F. R.
2017-04-01
This paper aims to add a reference in revealing spatial thinking. There several definitions of spatial thinking but it is not easy to defining it. We can start to discuss the concept, its basic a forming representation. Initially, the five sense catch the natural phenomenon and forward it to memory for processing. Abstraction plays a role in processing information into a concept. There are two types of representation, namely internal representation and external representation. The internal representation is also known as mental representation; this representation is in the human mind. The external representation may include images, auditory and kinesthetic which can be used to describe, explain and communicate the structure, operation, the function of the object as well as relationships. There are two main elements, representations properties and object relationships. These elements play a role in forming a representation.
Representability of Hom Implies Flatness
Nitin Nitsure
2004-02-01
Let be a projective scheme over a noetherian base scheme , and let $\\mathcal{F}$ be a coherent sheaf on . For any coherent sheaf $\\mathcal{E}$ on , consider the set-valued contravariant functor $\\hom_{(\\mathcal{E},\\mathcal{F})}$ on -schemes, defined by $\\hom_{(\\mathcal{E},\\mathcal{F})}(T)=\\mathrm{Hom}(\\mathcal{E}_T,\\mathcal{F}_T)$ where $\\mathcal{E}_T$ and $\\mathcal{F}_T$ are the pull-backs of $\\mathcal{E}$ and $\\mathcal{F}$ to $X_T=X×_s T$. A basic result of Grothendieck ([EGA], III 7.7.9) says that if $\\mathcal{F}$ is flat over then $\\hom_{(\\mathcal{E},\\mathcal{F})}$ is representable for all $\\mathcal{E}$. We prove the converse of the above, in fact, we show that if is a relatively ample line bundle on over such that the functor $\\hom_{(L^{-n},\\mathcal{F})}$ is representable for infinitely many positive integers , then $\\mathcal{F}$ is flat over . As a corollary, taking $X=S$, it follows that if $\\mathcal{F}$ is a coherent sheaf on then the functor $T\\mapsto H^0(T,\\mathcal{F}_T)$ on the category of -schemes is representable if and only if $\\mathcal{F}$ is locally free on . This answers a question posed by Angelo Vistoli. The techniques we use involve the proof of flattening stratification, together with the methods used in proving the author's earlier result (see [N1]) that the automorphism group functor of a coherent sheaf on is representable if and only if the sheaf is locally free.
Neural representation of spatial topology in the rodent hippocampus.
Chen, Zhe; Gomperts, Stephen N; Yamamoto, Jun; Wilson, Matthew A
2014-01-01
Pyramidal cells in the rodent hippocampus often exhibit clear spatial tuning in navigation. Although it has been long suggested that pyramidal cell activity may underlie a topological code rather than a topographic code, it remains unclear whether an abstract spatial topology can be encoded in the ensemble spiking activity of hippocampal place cells. Using a statistical approach developed previously, we investigate this question and related issues in greater detail. We recorded ensembles of hippocampal neurons as rodents freely foraged in one- and two-dimensional spatial environments and used a "decode-to-uncover" strategy to examine the temporally structured patterns embedded in the ensemble spiking activity in the absence of observed spatial correlates during periods of rodent navigation or awake immobility. Specifically, the spatial environment was represented by a finite discrete state space. Trajectories across spatial locations ("states") were associated with consistent hippocampal ensemble spiking patterns, which were characterized by a state transition matrix. From this state transition matrix, we inferred a topology graph that defined the connectivity in the state space. In both one- and two-dimensional environments, the extracted behavior patterns from the rodent hippocampal population codes were compared against randomly shuffled spike data. In contrast to a topographic code, our results support the efficiency of topological coding in the presence of sparse sample size and fuzzy space mapping. This computational approach allows us to quantify the variability of ensemble spiking activity, examine hippocampal population codes during off-line states, and quantify the topological complexity of the environment.
Representation Discovery using Harmonic Analysis
Mahadevan, Sridhar
2008-01-01
Representations are at the heart of artificial intelligence (AI). This book is devoted to the problem of representation discovery: how can an intelligent system construct representations from its experience? Representation discovery re-parameterizes the state space - prior to the application of information retrieval, machine learning, or optimization techniques - facilitating later inference processes by constructing new task-specific bases adapted to the state space geometry. This book presents a general approach to representation discovery using the framework of harmonic analysis, in particu
Representation of Performance Data in Grid Systems
时培植; 李三立
2004-01-01
The increasingly frequent exchange of performance data in grid systems across heterogeneous platforms requires a uniform "representation" of various types of performance data.This paper reviews the current related research,considers the defect of existing methods,and proposes a new portable description method: grid performance data description (GPDD) using an extensible markup language (XML)-based grid performance data representation language (XGPDRL).GPDD describes the abstract structure,which has excellent extensibility (all types of performance data can be described in one format),efficiency,and flexibility.XGPDRL defines the grammar of the GPDD performance data representation,and is both extensible and portable.For benchmarking purposes,performance data can be collected during runtime,represented in XGPDRL,and analyzed visually using a browser across heterogeneous platforms.GPDD and XGPDRL can conveniently ensure data comprehension across various platforms,and are very suitable for grid performance data representation.
Mental Representations Formed From Educational Website Formats
Elizabeth T. Cady; Kimberly R. Raddatz; Tuan Q. Tran; Bernardo de la Garza; Peter D. Elgin
2006-10-01
The increasing popularity of web-based distance education places high demand on distance educators to format web pages to facilitate learning. However, limited guidelines exist regarding appropriate writing styles for web-based distance education. This study investigated the effect of four different writing styles on reader’s mental representation of hypertext. Participants studied hypertext written in one of four web-writing styles (e.g., concise, scannable, objective, and combined) and were then administered a cued association task intended to measure their mental representations of the hypertext. It is hypothesized that the scannable and combined styles will bias readers to scan rather than elaborately read, which may result in less dense mental representations (as identified through Pathfinder analysis) relative to the objective and concise writing styles. Further, the use of more descriptors in the objective writing style will lead to better integration of ideas and more dense mental representations than the concise writing style.
Discrimination and the aim of proportional representation
Lippert-Rasmussen, Kasper
2008-01-01
Many organizations, companies, and so on are committed to certain representational aims as regards the composition of their workforce. One motivation for such aims is the assumption that numerical underrepresentation of groups manifests discrimination against them. In this article, I articulate...... representational aims in a way that best captures this rationale. My main claim is that the achievement of such representational aims is reducible to the elimination of the effects of wrongful discrimination on individuals and that this very important concern is, in principle, compatible with the representation...... of discrimination against numerically overrepresented groups, or overlook the innocently different ambitions of some numerically underrepresented groups. In relation to the latter point, I appeal to the fact that many luck egalitarians think justice should be ambition sensitive (but endowment insensitive). Also...
Social representations: a theoretical approach in health
Isaiane Santos Bittencourt
2011-03-01
Full Text Available Objective: To present the theory of social representations, placing its epistemology and knowing the basic concepts of its approach as a structural unit of knowledge for health studies. Justification: The use of this theory comes from the need to understand social eventsunder the lens of the meanings constructed by the community. Data Synthesis: This was a descriptive study of literature review, which used as a source of data collection the classical authors of social representations supported by articles from electronic search at Virtual Health Library (VHL. The definition and discussion of collected data enabled to introduce two themes, versed on the history and epistemology of representations and on the structuralapproach of representations in health studies. Conclusion: This review allowed highlight the importance of locating the objects of study with regard to contextual issues of individual and collective histories, valuing the plurality of relations, to come closer to reality that is represented by the subjects.
Discrimination and the aim of proportional representation
Lippert-Rasmussen, Kasper
2008-01-01
Many organizations, companies, and so on are committed to certain representational aims as regards the composition of their workforce. One motivation for such aims is the assumption that numerical underrepresentation of groups manifests discrimination against them. In this article, I articulate...... representational aims in a way that best captures this rationale. My main claim is that the achievement of such representational aims is reducible to the elimination of the effects of wrongful discrimination on individuals and that this very important concern is, in principle, compatible with the representation...... of discrimination against numerically overrepresented groups, or overlook the innocently different ambitions of some numerically underrepresented groups. In relation to the latter point, I appeal to the fact that many luck egalitarians think justice should be ambition sensitive (but endowment insensitive). Also...
Normalized neural representations of natural odors
Zwicker, David
2016-01-01
The olfactory system removes correlations in natural odors using a network of inhibitory neurons in the olfactory bulb. It has been proposed that this network integrates the response from all olfactory receptors and inhibits them equally. However, how such global inhibition influences the neural representations of odors is unclear. Here, we study a simple statistical model of this situation, which leads to concentration-invariant, sparse representations of the odor composition. We show that the inhibition strength can be tuned to obtain sparse representations that are still useful to discriminate odors that vary in relative concentration, size, and composition. The model reveals two generic consequences of global inhibition: (i) odors with many molecular species are more difficult to discriminate and (ii) receptor arrays with heterogeneous sensitivities perform badly. Our work can thus help to understand how global inhibition shapes normalized odor representations for further processing in the brain.
Soffer, Michal; Rimmerman, Arie
2012-01-01
This feasibility study examines the coverage of employment-related issues related to people with disabilities in the Americans with Disabilities Act of 1990. The study is a first in a series of future studies focusing on disability issues in the international economic media. A survey of 39 newspaper articles published in the "Wall Street…
Soffer, Michal; Rimmerman, Arie
2012-01-01
This feasibility study examines the coverage of employment-related issues related to people with disabilities in the Americans with Disabilities Act of 1990. The study is a first in a series of future studies focusing on disability issues in the international economic media. A survey of 39 newspaper articles published in the "Wall Street…
Towards Multimodal Content Representation
Bunt, Harry
2009-01-01
Multimodal interfaces, combining the use of speech, graphics, gestures, and facial expressions in input and output, promise to provide new possibilities to deal with information in more effective and efficient ways, supporting for instance: - the understanding of possibly imprecise, partial or ambiguous multimodal input; - the generation of coordinated, cohesive, and coherent multimodal presentations; - the management of multimodal interaction (e.g., task completion, adapting the interface, error prevention) by representing and exploiting models of the user, the domain, the task, the interactive context, and the media (e.g. text, audio, video). The present document is intended to support the discussion on multimodal content representation, its possible objectives and basic constraints, and how the definition of a generic representation framework for multimodal content representation may be approached. It takes into account the results of the Dagstuhl workshop, in particular those of the informal working group...
Post-representational cartography
Rob Kitchin
2010-03-01
Full Text Available Over the past decade there has been a move amongst critical cartographers to rethink maps from a post-representational perspective – that is, a vantage point that does not privilege representational modes of thinking (wherein maps are assumed to be mirrors of the world and automatically presumes the ontological security of a map as a map, but rather rethinks and destabilises such notions. This new theorisation extends beyond the earlier critiques of Brian Harley (1989 that argued maps were social constructions. For Harley a map still conveyed the truth of a landscape, albeit its message was bound within the ideological frame of its creator. He thus advocated a strategy of identifying the politics of representation within maps in order to circumnavigate them (to reveal the truth lurking underneath, with the ontology of cartographic practice remaining unquestioned.
Learning network representations
Moyano, Luis G.
2017-02-01
In this review I present several representation learning methods, and discuss the latest advancements with emphasis in applications to network science. Representation learning is a set of techniques that has the goal of efficiently mapping data structures into convenient latent spaces. Either for dimensionality reduction or for gaining semantic content, this type of feature embeddings has demonstrated to be useful, for example, for node classification or link prediction tasks, among many other relevant applications to networks. I provide a description of the state-of-the-art of network representation learning as well as a detailed account of the connections with other fields of study such as continuous word embeddings and deep learning architectures. Finally, I provide a broad view of several applications of these techniques to networks in various domains.
Hilton, Annette; Nichols, Kim
2011-11-01
Understanding bonding is fundamental to success in chemistry. A number of alternative conceptions related to chemical bonding have been reported in the literature. Research suggests that many alternative conceptions held by chemistry students result from previous teaching; if teachers are explicit in the use of representations and explain their content-specific forms and functions, this might be avoided. The development of an understanding of and ability to use multiple representations is crucial to students' understanding of chemical bonding. This paper draws on data from a larger study involving two Year 11 chemistry classes (n = 27, n = 22). It explores the contribution of explicit instruction about multiple representations to students' understanding and representation of chemical bonding. The instructional strategies were documented using audio-recordings and the teacher-researcher's reflection journal. Pre-test-post-test comparisons showed an improvement in conceptual understanding and representational competence. Analysis of the students' texts provided further evidence of the students' ability to use multiple representations to explain macroscopic phenomena on the molecular level. The findings suggest that explicit instruction about representational form and function contributes to the enhancement of representational competence and conceptual understanding of bonding in chemistry. However, the scaffolding strategies employed by the teacher play an important role in the learning process. This research has implications for professional development enhancing teachers' approaches to these aspects of instruction around chemical bonding.
黄雪萍; 邓敏; 吴静; 马杭英
2013-01-01
It is difficult to express and distinguish complex location relationship information of two spatial objects through single topological relations, directional relations and distance relations. Using natural language as the description tool, the positional description of a line and an area is studied. We propose an integrated representation method of natural-language spatial relations between a line and an area according to the decomposition-combination measure. Firstly, n characteristic points and n - 1 characteristic lines would be obtained from refining and decomposing the linear object, whose spatial relations with the areal objects could be built by contraposing each of the characteristic points and lines according to the descriptive habits of natural-language. Secondly, we integrate the description of the topological relations, directional relations and distance relations according to the rules of the describing of natural-language spatial relations between lines and regions in the sequence of the directions of the lineal object. Finally, comprehensive experiments are performed to demonstrate the feasibility and efficiency of the transformation between graphic spatial relations and natural-language spatial relations.%提出了一种基于自然语言的线/面目标空间关系集成表达方法.首先,将线目标进行细化分解得到n个特征点和n—1条特征线,根据自然语言的描述习惯分别针对每个特征点和特征线建立线与面目标之间的空间关系,然后按照自然语言以线目标的走向为顺序对线面间空间关系进行描述的规则,对拓扑、方向、度量关系进行集成描述.实验验证了本文方法的可行性.
Mobilities and Representations
Thelle, Mikkel
2016-01-01
, literature, and film. Moreover, we hope the authors of future reviews will reflect on the ways they approached those representations. Such commentaries would provide valuable methodological insights, and we hope to begin that effort with this interview. We have asked four prominent mobility scholars...... to consider how they and their peers are currently confronting representations of mobility. This is particularly timely given the growing academic focus on practices, material mediation, and nonrepresentational theories, as well as on bodily reactions, emotions, and feelings that, according to those theories...
Additive and polynomial representations
Krantz, David H; Suppes, Patrick
1971-01-01
Additive and Polynomial Representations deals with major representation theorems in which the qualitative structure is reflected as some polynomial function of one or more numerical functions defined on the basic entities. Examples are additive expressions of a single measure (such as the probability of disjoint events being the sum of their probabilities), and additive expressions of two measures (such as the logarithm of momentum being the sum of log mass and log velocity terms). The book describes the three basic procedures of fundamental measurement as the mathematical pivot, as the utiliz
The Spatial Politics of Spatial Representation
Olesen, Kristian; Richardson, Tim
2011-01-01
This paper explores the interplay between the spatial politics of new governance landscapes and innovations in the use of spatial representations in planning. The central premise is that planning experiments with new relational approaches become enmeshed in spatial politics. The case of strategic...... spatial planning in Denmark reveals how fuzzy spatial representations and relational spatial concepts are being used to depoliticise strategic spatial planning processes and to camouflage spatial politics. The paper concludes that, while relational geography might play an important role in building...... consensus, it plays an equal important role in supporting current neoliberal transformations of strategic spatial planning....
Van Otterlo, M
2009-01-01
Markov decision processes have become the de facto standard in modeling and solving sequential decision making problems under uncertainty. This book studies lifting Markov decision processes, reinforcement learning and dynamic programming to the first-order (or, relational) setting.
Body representation in patients after vascular brain injuries.
Razmus, Magdalena
2017-08-29
Neuropsychological literature suggests that body representation is a multidimensional concept consisting of various types of representations. Previous studies have demonstrated dissociations between three types of body representation specified by the kind of data and processes, i.e. body schema, body structural description, and body semantics. The aim of the study was to describe the state of body representation in patients after vascular brain injuries and to provide evidence for the different types of body representation. The question about correlations between body representation deficits and neuropsychological dysfunctions was also investigated. Fifty patients after strokes and 50 control individuals participated in the study. They were examined with tasks referring to dynamic representation of body parts positions, topological body map, and lexical and semantic knowledge about the body. Data analysis showed that vascular brain injuries result in deficits of body representation, which may co-occur with cognitive dysfunctions, but the latter are a possible risk factor for body representation deficits rather than sufficient or imperative requisites for them. The study suggests that types of body representation may be separated on the basis not only of their content, but also of their relation with self. Principal component analysis revealed three factors, which explained over 66% of results variance. The factors, which may be interpreted as types or dimensions of mental model of a body, represent different degrees of connection with self. The results indicate another possibility of body representation types classification, which should be verified in future research.
Moment graphs and representations
Jantzen, Jens Carsten
2012-01-01
Moment graphs and sheaves on moment graphs are basically combinatorial objects that have be used to describe equivariant intersectiion cohomology. In these lectures we are going to show that they can be used to provide a direct link from this cohomology to the representation theory of simple Lie...
Compact Information Representations
2016-08-02
network traffic, information retrieval, and databases are faced with very large, inherently high-dimensional, or naturally streaming datasets. This...proposal aims at developing mathematically rigorous and general- purpose statistical methods based on stable random projections, to achieve compact...detections (e.g., DDoS attacks), machine learning, databases , and search. Fundamentally, compact data representations are highly beneficial because they
Representation and human reasoning
ter Meulen, Alice G.B.
2003-01-01
Interpretation and reasoning are two sides of sharing information. Representations of the context and common ground must capture the rich content of what has been said, by linking to situations in the world as well as to what has been said before, common sense and to the presuppositions and entailme
Moment graphs and representations
Jantzen, Jens Carsten
2012-01-01
Moment graphs and sheaves on moment graphs are basically combinatorial objects that have be used to describe equivariant intersectiion cohomology. In these lectures we are going to show that they can be used to provide a direct link from this cohomology to the representation theory of simple Lie...... algebras and of simple algebraic groups. The first section contains some background on equivariant cohomology....
Loddegaard, Anne
2009-01-01
out of place in a novel belonging to the serious combat literature of the Catholic Revival, and the direct representation of the supernatural is also surprising because previous Catholic Revival novelists, such as Léon Bloy and Karl-Joris Huysmans, maintain a realistic, non-magical world and deal...
Loddegaard, Anne
2012-01-01
out of place in a novel belonging to the serious combat literature of the Catholic Revival, and the direct representation of the supernatural is also surprising because previous Catholic Revival novelists, such as Léon Bloy and Karl-Joris Huysmans, maintain a realistic, non-magical world and deal...
Women and political representation.
Rathod, P B
1999-01-01
A remarkable progress in women's participation in politics throughout the world was witnessed in the final decade of the 20th century. According to the Inter-Parliamentary Union report, there were only eight countries with no women in their legislatures in 1998. The number of women ministers at the cabinet level worldwide doubled in a decade, and the number of countries without any women ministers dropped from 93 to 48 during 1987-96. However, this progress is far from satisfactory. Political representation of women, minorities, and other social groups is still inadequate. This may be due to a complex combination of socioeconomic, cultural, and institutional factors. The view that women's political participation increases with social and economic development is supported by data from the Nordic countries, where there are higher proportions of women legislators than in less developed countries. While better levels of socioeconomic development, having a women-friendly political culture, and higher literacy are considered favorable factors for women's increased political representation, adopting one of the proportional representation systems (such as a party-list system, a single transferable vote system, or a mixed proportional system with multi-member constituencies) is the single factor most responsible for the higher representation of women.
Sociocognitive Perspectives on Representation.
Jacob, Elin K.; Shaw, Debora
1998-01-01
Discusses research dealing with the cognitive aspects of formal systems of knowledge representation. Highlights include the origins and theoretical foundations of the cognitive viewpoint; cognition and information science; cognitivism, mentalism, and subjective individualism; categorization; mental models; and sociocognitive approaches to indexing…
Between Representation and Eternity
Atzbach, Rainer
2016-01-01
. At death, an indi- vidual’s corpse and burial primarily reflect the social act of representation during the funeral. The position of the arms, which have incorrectly been used as a chronological tool in Scandinavia, may indicate an evolution from a more collective act of prayer up to the eleventh century...
Sociocognitive Perspectives on Representation.
Jacob, Elin K.; Shaw, Debora
1998-01-01
Discusses research dealing with the cognitive aspects of formal systems of knowledge representation. Highlights include the origins and theoretical foundations of the cognitive viewpoint; cognition and information science; cognitivism, mentalism, and subjective individualism; categorization; mental models; and sociocognitive approaches to indexing…
Spectral representation of fingerprints
Xu, Haiyun; Bazen, Asker M.; Veldhuis, Raymond N.J.; Kevenaar, Tom A.M.; Akkermans, Anton H.M.
2007-01-01
Most fingerprint recognition systems are based on the use of a minutiae set, which is an unordered collection of minutiae locations and directions suffering from various deformations such as translation, rotation and scaling. The spectral minutiae representation introduced in this paper is a novel m
Mental Representation and Motor Imagery Training
Thomas eSchack
2014-05-01
Full Text Available Research in sports, dance and rehabilitation has shown that Basic Action Concepts (BACs are fundamental building blocks of mental action representations. BACs are based on chunked body postures related to common functions for realizing action goals. In this paper, we outline issues in research methodology and an experimental method, SDA-M (structural dimensional analysis of mental representation, to assess action-relevant representational structures that reflect the organization of BACs. The SDA-M reveals a strong relationship between cognitive representation and performance if complex actions are performed. We show how the SDA-M can improve motor imagery training and how it contributes to our understanding of coaching processes. The SDA-M capitalizes on the objective measurement of individual mental movement representations before training and the integration of these results into the motor imagery training. Such motor imagery training based on mental representations has been applied successfully in professional sports such as golf, volleyball, gymnastics, windsurfing, and recently in the rehabilitation of patients who have suffered a stroke.
Two-Dimensional Theory of Scientific Representation
A Yaghmaie
2013-03-01
Full Text Available Scientific representation is an interesting topic for philosophers of science, many of whom have recently explored it from different points of view. There are currently two competing approaches to the issue: cognitive and non-cognitive, and each of them claims its own merits over the other. This article tries to provide a hybrid theory of scientific representation, called Two-Dimensional Theory of Scientific Representation, which has the merits of the two accounts and is free of their shortcomings. To do this, we will argue that although scientific representation needs to use the notion of intentionality, such a notion is defined and realized in a simply structural form contrary to what cognitive approach says about intentionality. After a short introduction, the second part of the paper is devoted to introducing theories of scientific representation briefly. In the third part, the structural accounts of representation will be criticized. The next step is to introduce the two-dimensional theory which involves two key components: fixing and structural fitness. It will be argued that fitness is an objective and non-intentional relation, while fixing is intentional.
Collard-Fortin, Ugo
Le developpement des sciences/technologie a tres clairement contribue a ce que ce dernier domaine de savoirs jouisse d'une place de choix au sein de notre societe. Au-dela des progres de notre civilisation inherents a ce dernier developpement, cette croissance amena avec elle un lot d'ineluctables dommages collateraux, contribuant en corollaire a l'emergence de diverses problematiques environnementales inquietantes pour lesquelles les valeurs ainsi que le mode de fonctionnement de la societe occidentale contemporaine sont largement tributaires. C'est entre autres en reponse a cet etat de fait que la recente vague de reforme de l'Education conduisit a l'integration, dans les curricula de sciences/technologie, de contenus relavant d'education relative a l'environnement (ERE). Face au changement, les enseignants de sciences ont du s'approprier ce nouveau programme afm de l'enseigner a leurs eleves. Toutefois, l'analyse de la situation montre que les prescriptions du programme en matiere d'ERE ne se sont pas toujours traduites en de reelles actions dans la pratique. Le contexte de notre etude s'est interesse aux pratiques educatives de l'ERE ainsi qu'a la representation sociale qui en decoule. Notre recherche aborde plus specifiquement la problematique de la modification de ces derniers objets chez les enseignants de sciences et technologie du deuxieme cycle du secondaire. Pour y arriver, nous avons propose a un groupe de trois praticiens de participer a une activite, en communaute de pratique, de formation continue orientee autour de thematiques ERE. Cette recherche developpement, s'inscrivant dans un paradigme qualitatif/interpretatif, s'est appuyee sur une cueillette de donnees effectuee a partir d'entrevues semi-dirigees, d'observations en situation et d'un groupe de discussion, au debut et a la fm de la formation continue. Les donnees brutes ont ete soumises a une demarche d'analyse inductive et ont genere diverses categories etayant nos objets de recherche
Twisted Fock representations of noncommutative Kähler manifolds
Sako, Akifumi; Umetsu, Hiroshi
2016-09-01
We introduce twisted Fock representations of noncommutative Kähler manifolds and give their explicit expressions. The twisted Fock representation is a representation of the Heisenberg like algebra whose states are constructed by applying creation operators to a vacuum state. "Twisted" means that creation operators are not Hermitian conjugate of annihilation operators in this representation. In deformation quantization of Kähler manifolds with separation of variables formulated by Karabegov, local complex coordinates and partial derivatives of the Kähler potential with respect to coordinates satisfy the commutation relations between the creation and annihilation operators. Based on these relations, we construct the twisted Fock representation of noncommutative Kähler manifolds and give a dictionary to translate between the twisted Fock representations and functions on noncommutative Kähler manifolds concretely.
Twisted Fock Representations of Noncommutative K\\"ahler Manifolds
Sako, Akifumi
2016-01-01
We introduce twisted Fock representations of noncommutative K\\"ahler manifolds and give their explicit expressions. The twisted Fock representation is a representation of the Heisenberg like algebra whose states are constructed by acting creation operators on a vacuum state. "Twisted" means that creation operators are not hermitian conjugate of annihilation operators in this representation. In deformation quantization of K\\"ahler manifolds with separation of variables formulated by Karabegov, local complex coordinates and partial derivatives of the K\\"ahler potential with respect to coordinates satisfy the commutation relations between the creation and annihilation operators. Based on these relations, we construct the twisted Fock representation of noncommutative K\\"ahler manifolds and give a dictionary to translate between the twisted Fock representations and functions on noncommutative K\\"ahler manifolds concretely.
Realizations of the Canonical Representation
M K Vemuri
2008-02-01
A characterisation of the maximal abelian subalgebras of the bounded operators on Hilbert space that are normalised by the canonical representation of the Heisenberg group is given. This is used to classify the perfect realizations of the canonical representation.
Standard model of knowledge representation
Yin, Wensheng
2016-09-01
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.
Quiver representations and quiver varieties
Jr, Alexander Kirillov
2016-01-01
This book is an introduction to the theory of quiver representations and quiver varieties, starting with basic definitions and ending with Nakajima's work on quiver varieties and the geometric realization of Kac-Moody Lie algebras. The first part of the book is devoted to the classical theory of quivers of finite type. Here the exposition is mostly self-contained and all important proofs are presented in detail. The second part contains the more recent topics of quiver theory that are related to quivers of infinite type: Coxeter functor, tame and wild quivers, McKay correspondence, and representations of Euclidean quivers. In the third part, topics related to geometric aspects of quiver theory are discussed, such as quiver varieties, Hilbert schemes, and the geometric realization of Kac-Moody algebras. Here some of the more technical proofs are omitted; instead only the statements and some ideas of the proofs are given, and the reader is referred to original papers for details. The exposition in the book requ...
Representation and Perspective in Science
Bas C. van Fraassen
2007-12-01
Full Text Available The world science describes tends to have a very strange look. We can’t see atoms or force fields, nor are they imaginable within visualizable categories, so neither can we even imagine what the world must be like according to recent physical theories. That tension, between what science depicts as reality and how things appear to us, though it is more striking now, has been with us since modern science began. It can be addressed, and perhaps alleviated by inquiring into how science represents nature. In general, representation is selective, the selection is of what is relevant to the purpose at hand, and success may even require distortion. From this point of view, the constraint on science, that it must ‘save the phenomena’, takes on a new form. The question to be faced is how the perspectival character of the appearances (that is, contents of measurement outcomes can be related to the hidden structure that the sciences postulate. In the competing interpretations of quantum mechanics we can see how certain traditional ideals and constraints are left behind. Specifically, Carlo Rovelli’s Relational Quantum Mechanics offers a probative example of the freedom of scientific representation.
Asymmetrical Body Perception: A Possible Role for Neural Body Representations
2009-01-01
Perception of one's body is related not only to the physical appearance of the body, but also to the neural representation of the body. The brain contains many body maps that systematically differ between right- and left-handed people. In general, the cortical representations of the right arm and right hand tend to be of greater area in the left hemisphere than in the right hemisphere for right-handed people, whereas these cortical representations tend to be symmetrical across hemispheres for...
Using Distributed Representations to Disambiguate Biomedical and Clinical Concepts
Tulkens, Stéphan; Šuster, Simon; Daelemans, Walter
2016-01-01
In this paper, we report a knowledge-based method for Word Sense Disambiguation in the domains of biomedical and clinical text. We combine word representations created on large corpora with a small number of definitions from the UMLS to create concept representations, which we then compare to representations of the context of ambiguous terms. Using no relational information, we obtain comparable performance to previous approaches on the MSH-WSD dataset, which is a well-known dataset in the bi...
Dimer representations of the Temperley-Lieb algebra
Morin-Duchesne, Alexi; Ruelle, Philippe
2014-01-01
A new spin-chain representation of the Temperley-Lieb algebra $TL_n(\\beta=0)$ is introduced and related to the dimer model. Unlike the usual XXZ spin-chain representations of dimension $2^n$, this dimer representation is of dimension $2^{n-1}$. A detailed analysis of its structure is presented and found to yield indecomposable zigzag modules not appearing in traditional spin-chain scenarios.
Dimer representations of the Temperley–Lieb algebra
Morin-Duchesne, Alexi, E-mail: alexi.morin-duchesne@uclouvain.be [Institut de Recherche en Mathématique et Physique, Université Catholique de Louvain, Louvain-la-Neuve, B-1348 (Belgium); Rasmussen, Jørgen, E-mail: j.rasmussen@uq.edu.au [School of Mathematics and Physics, University of Queensland St Lucia, Brisbane, Queensland 4072 (Australia); Ruelle, Philippe, E-mail: philippe.ruelle@uclouvain.be [Institut de Recherche en Mathématique et Physique, Université Catholique de Louvain, Louvain-la-Neuve, B-1348 (Belgium)
2015-01-15
A new spin-chain representation of the Temperley–Lieb algebra TL{sub n}(β=0) is introduced and related to the dimer model. Unlike the usual XXZ spin-chain representations of dimension 2{sup n}, this dimer representation is of dimension 2{sup n−1}. A detailed analysis of its structure is presented and found to yield indecomposable zigzag modules.
Gestalt-like representations hijack Chunk-and-Pass processing.
Dumitru, Magda L
2016-01-01
Christiansen & Chater (C&C) make two related and somewhat contradictory claims, namely that the ever abstract language representations built during Chunk-and-Pass processing allow for ever greater interference from extra-linguistic information, and that it is nevertheless the language system that re-codes incoming information into abstract representations. I analyse these claims and discuss evidence suggesting that Gestalt-like representations hijack Chunk-and-Pass processing.
Harmonic Analysis and Group Representation
Figa-Talamanca, Alessandro
2011-01-01
This title includes: Lectures - A. Auslander, R. Tolimeri - Nilpotent groups and abelian varieties, M Cowling - Unitary and uniformly bounded representations of some simple Lie groups, M. Duflo - Construction de representations unitaires d'un groupe de Lie, R. Howe - On a notion of rank for unitary representations of the classical groups, V.S. Varadarajan - Eigenfunction expansions of semisimple Lie groups, and R. Zimmer - Ergodic theory, group representations and rigidity; and, Seminars - A. Koranyi - Some applications of Gelfand pairs in classical analysis.
Representations of intercourse in American literature
Jensen, Kim Ebensgaard
2014-01-01
This article investigates the representation of sexual intercourse in American literature expressed via the use of fuck as a transitive verb. Its goal is to identify possible trends in the differentiation between men and women's roles and power relations in such literary representations. Drawing...... on theoretical notions from cognitive poetics, the present article assumes that literary representations of intercourse reflect and replicate in readers cognitive-cultural models of intercourse and the roles of, and power relations between, men and women therein. The analysis presented here is quantitative...... and falls under the rubric of corpus stylistics and is based on data from the FICTION component of the Corpus of Historical American English. The analysis measures the preference of male or female passive participants in propositional scenarios denoted by transitive fuck, thus allowing...
刘兆敏; 郭春彦
2013-01-01
Human memory can be characterized as an elaborate network of stored representations. Researchers propose that both working memory (WM) and long-term memory (LTM) utilize same representations, and the representations they activate are in diverse patterns. So the similarity and coherence between WM and LTM are emphasized in the activation-based model, and the priming effect of LTM on WM and vice versa should be both found. By simultaneously recording event-related potentials (ERPs), the present study aimed to investigate two long-term semantic priming effects to illustrate the common representations involved in WM and LTM. Fifteen college students (mean age=20.33±1.91; 7 male) participated in the experiment. The participants were all right-hand, had normal or corrected-to-normal vision and had no neurological or psychological disorders. Each participant signed a consent form prior to experiment and was paid after experiment. We combined a WM component (short-term verbal encoding) and a LTM component (category comparison) into one task, so that WM and LTM processing could be concurrently investigated. LTM priming on WM was manipulated by asking participants to learn before short-term verbal encoding, and the priming effect of WM on related LTM should be found in category comparison. Results revealed two long-term semantic priming effects in behavior data and ERPs. The first effect was found in short-term encoding phase, which was reflected as the priming of LTM on WM. Compared with new targets in WM, the reaction time of studied targets was shorter. They elicitedearlier N2 and P3, and they also decreased N2 amplitude. These may index the so-called neural priming (or repetition suppression) of scalp potentials. However, there was no difference between new and studied distractors in WM. Furthermore, the neural priming of WM on LTM also exhibited in category comparison. Specific contents, which were formerly concerned or ignored in short-term encoding phase, led
Sannino, Francesco
2010-01-01
We uncover novel solutions of the 't Hooft anomaly matching conditions for scalarless gauge theories with matter transforming according to higher dimensional representations of the underlying gauge group. We argue that, if the duals exist, they are gauge theories with fermions transforming...... according to the defining representation of the dual gauge group. The resulting conformal windows match the one stemming from the all-orders beta function results when taking the anomalous dimension of the fermion mass to be unity which are also very close to the ones obtained using the Schwinger......-Dyson approximation. We use the solutions to gain useful insight on the conformal window of the associated electric theory. A consistent picture emerges corroborating previous results obtained via different analytic methods and in agreement with first principle lattice explorations....
Constructing visual representations
Huron, Samuel; Jansen, Yvonne; Carpendale, Sheelagh
2014-01-01
The accessibility of infovis authoring tools to a wide audience has been identified as a major research challenge. A key task in the authoring process is the development of visual mappings. While the infovis community has long been deeply interested in finding effective visual mappings......, comparatively little attention has been placed on how people construct visual mappings. In this paper, we present the results of a study designed to shed light on how people transform data into visual representations. We asked people to create, update and explain their own information visualizations using only...... tangible building blocks. We learned that all participants, most of whom had little experience in visualization authoring, were readily able to create and talk about their own visualizations. Based on our observations, we discuss participants’ actions during the development of their visual representations...
Graphical representations of Ising and Potts models
Björnberg, Jakob E
2010-01-01
We study graphical representations for two related models. The first model is the transverse field quantum Ising model, an extension of the original Ising model which was introduced by Lieb, Schultz and Mattis in the 1960's. The second model is the space-time percolation process, which is closely related to the contact model for the spread of disease. We consider a `space-time' random-cluster model and explore a range of useful probabilistic techniques for studying it. The space-time Potts model emerges as a natural generalization of the quantum Ising model. The basic properties of the phase transitions in these models are treated, such as the fact that there is at most one unbounded FK-cluster, and the resulting lower bound on the critical value in $\\ZZ$. We also develop an alternative graphical representation of the quantum Ising model, called the random-parity representation. This representation is based on the random-current representation of the classical Ising model, and allows us to study in much great...
Comprehension and Representation in Translation
徐玉萍
2010-01-01
Transhfion is the faithful rcpresentation in one language of the thought, content, feeling and style written in another language. It involves two processes: comprehension and representation. Correct comprehension is the base for adequate representation. Criteria for good representation lies in two points: the version should be faithful to the original, and the version should be as intelligible as possible.
Learning Multisensory Representations
2016-05-23
AFRL-AFOSR-VA-TR-2016-0183 Learning Multisensory Representations Robert Jacobs UNIVERSITY OF ROCHESTER Final Report 05/23/2016 DISTRIBUTION A...DD-MM-YYYY) 16-05-2016 2. REPORT TYPE Final Performance Report 3. DATES COVERED (From - To) 01-09-2012 - 29-02-2016 4. TITLE AND SUBTITLE Learning ...perception; visual perception; haptic perception; auditory perception; perceptual learning ; perceptual decision making 16. SECURITY CLASSIFICATION OF
Jensen, Ole B.
2016-01-01
Dette kapitel gennemgår den såkaldte ”Non-Representational Theory” (NRT), der primært er kendt fra den Angelsaksiske humangeografi, og som særligt er blevet fremført af den engelske geograf Nigel Thrift siden midten af 2000 årtiet. Da positionen ikke kan siges at være specielt homogen vil kapitlet...
The field representation language.
Tsafnat, Guy
2008-02-01
The complexity of quantitative biomedical models, and the rate at which they are published, is increasing to a point where managing the information has become all but impossible without automation. International efforts are underway to standardise representation languages for a number of mathematical entities that represent a wide variety of physiological systems. This paper presents the Field Representation Language (FRL), a portable representation of values that change over space and/or time. FRL is an extensible mark-up language (XML) derivative with support for large numeric data sets in Hierarchical Data Format version 5 (HDF5). Components of FRL can be reused through unified resource identifiers (URI) that point to external resources such as custom basis functions, boundary geometries and numerical data. To demonstrate the use of FRL as an interchange we present three models that study hyperthermia cancer treatment: a fractal model of liver tumour microvasculature; a probabilistic model simulating the deposition of magnetic microspheres throughout it; and a finite element model of hyperthermic treatment. The microsphere distribution field was used to compute the heat generation rate field around the tumour. We used FRL to convey results from the microsphere simulation to the treatment model. FRL facilitated the conversion of the coordinate systems and approximated the integral over regions of the microsphere deposition field.
Translation between representation languages
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.
Pioneers of representation theory
Curtis, Charles W
1999-01-01
The year 1897 was marked by two important mathematical events: the publication of the first paper on representations of finite groups by Ferdinand Georg Frobenius (1849-1917) and the appearance of the first treatise in English on the theory of finite groups by William Burnside (1852-1927). Burnside soon developed his own approach to representations of finite groups. In the next few years, working independently, Frobenius and Burnside explored the new subject and its applications to finite group theory. They were soon joined in this enterprise by Issai Schur (1875-1941) and some years later, by Richard Brauer (1901-1977). These mathematicians' pioneering research is the subject of this book. It presents an account of the early history of representation theory through an analysis of the published work of the principals and others with whom the principals' work was interwoven. Also included are biographical sketches and enough mathematics to enable readers to follow the development of the subject. An introductor...
Richard, Nelly; Laursen, Bettina; Grupe, Morten; Drewes, Asbjørn M.; Graversen, Carina; Sørensen, Helge B. D.; Bastlund, Jesper F.
2017-04-01
Objective. Active auditory oddball paradigms are simple tone discrimination tasks used to study the P300 deflection of event-related potentials (ERPs). These ERPs may be quantified by time-frequency analysis. As auditory stimuli cause early high frequency and late low frequency ERP oscillations, the continuous wavelet transform (CWT) is often chosen for decomposition due to its multi-resolution properties. However, as the conventional CWT traditionally applies only one mother wavelet to represent the entire spectrum, the time-frequency resolution is not optimal across all scales. To account for this, we developed and validated a novel method specifically refined to analyse P300-like ERPs in rats. Approach. An adapted CWT (aCWT) was implemented to preserve high time-frequency resolution across all scales by commissioning of multiple wavelets operating at different scales. First, decomposition of simulated ERPs was illustrated using the classical CWT and the aCWT. Next, the two methods were applied to EEG recordings obtained from prefrontal cortex in rats performing a two-tone auditory discrimination task. Main results. While only early ERP frequency changes between responses to target and non-target tones were detected by the CWT, both early and late changes were successfully described with strong accuracy by the aCWT in rat ERPs. Increased frontal gamma power and phase synchrony was observed particularly within theta and gamma frequency bands during deviant tones. Significance. The study suggests superior performance of the aCWT over the CWT in terms of detailed quantification of time-frequency properties of ERPs. Our methodological investigation indicates that accurate and complete assessment of time-frequency components of short-time neural signals is feasible with the novel analysis approach which may be advantageous for characterisation of several types of evoked potentials in particularly rodents.
Sturm, Irene; Blankertz, Benjamin; Potes, Cristhian; Schalk, Gerwin; Curio, Gabriel
2014-01-01
Listening to music moves our minds and moods, stirring interest in its neural underpinnings. A multitude of compositional features drives the appeal of natural music. How such original music, where a composer's opus is not manipulated for experimental purposes, engages a listener's brain has not been studied until recently. Here, we report an in-depth analysis of two electrocorticographic (ECoG) data sets obtained over the left hemisphere in ten patients during presentation of either a rock song or a read-out narrative. First, the time courses of five acoustic features (intensity, presence/absence of vocals with lyrics, spectral centroid, harmonic change, and pulse clarity) were extracted from the audio tracks and found to be correlated with each other to varying degrees. In a second step, we uncovered the specific impact of each musical feature on ECoG high-gamma power (70-170 Hz) by calculating partial correlations to remove the influence of the other four features. In the music condition, the onset and offset of vocal lyrics in ongoing instrumental music was consistently identified within the group as the dominant driver for ECoG high-gamma power changes over temporal auditory areas, while concurrently subject-individual activation spots were identified for sound intensity, timbral, and harmonic features. The distinct cortical activations to vocal speech-related content embedded in instrumental music directly demonstrate that song integrated in instrumental music represents a distinct dimension in complex music. In contrast, in the speech condition, the full sound envelope was reflected in the high gamma response rather than the onset or offset of the vocal lyrics. This demonstrates how the contributions of stimulus features that modulate the brain response differ across the two examples of a full-length natural stimulus, which suggests a context-dependent feature selection in the processing of complex auditory stimuli.
Irene eSturm
2014-10-01
Full Text Available Listening to music moves our minds and moods, stirring interest in its neural underpinnings. A multitude of compositional features drives the appeal of natural music. How such original music, where a composer's opus is not manipulated for experimental purposes, engages a listener's brain has not been studied until recently. Here, we report an in-depth analysis of two electrocorticographic (ECoG data sets obtained over the left hemisphere in ten patients during presentation of either a rock song or a read-out narrative. First, the time courses of five acoustic features (intensity, presence/absence of vocals with lyrics, spectral centroid, harmonic change, and pulse clarity were extracted from the audio tracks and found to be correlated with each other to varying degrees. In a second step, we uncovered the specific impact of each musical feature on ECoG high-gamma power (70-170 Hz by calculating partial correlations to remove the influence of the other four features. In the music condition, the onset and offset of vocal lyrics in ongoing instrumental music was consistently within the subject group identified as the dominant driver for ECoG high-gamma power changes over temporal auditory areas, while concurrently subject-individual activation spots were identified for sound intensity, timbral and harmonic features. The distinct cortical activations to vocal speech-related content embedded in instrumental music directly demonstrate that song overlaid on instrumental music represents a distinct dimension in complex music. In contrast, in the speech condition, the full sound envelope was reflected in the high gamma response rather than the onset or offset of the vocal lyrics. This demonstrates how the contributions of stimulus features that modulate the brain response differ across the two examples of a full-length natural stimulus, which suggests a context-dependent feature selection in the processing of complex auditory stimuli.
Unpacking Exoplanet Detection Using Pedagogical Discipline Representations (PDRs)
Prather, Edward E.; Chambers, Timothy G.; Wallace, Colin Scott; Brissenden, Gina
2017-01-01
Successful educators know the importance of using multiple representations to teach the content of their disciplines. We have all seen the moments of epiphany that can be inspired when engaging with just the right representation of a difficult concept. The formal study of the cognitive impact of different representations on learners is now an active area of education research. The affordances of a particular representation are defined as the elements of disciplinary knowledge that students are able to access and reason about using that representation. Instructors with expert pedagogical content knowledge teach each topic using representations with complementary affordances, maximizing their students’ opportunity to develop fluency with all aspects of the topic. The work presented here examines how we have applied the theory of affordances to the development of pedagogical discipline representation (PDR) in an effort to provide access to, and help non-science-majors engage in expert-like reasoning about, general relativity as applied to detection of exoplanets. We define a pedagogical discipline representation (PDR) as a representation that has been uniquely tailored for the purpose of teaching a specific topic within a discipline. PDRs can be simplified versions of expert representations or can be highly contextualized with features that purposefully help unpack specific reasoning or concepts, and engage learners’ pre-existing mental models while promoting and enabling critical discourse. Examples of PDRs used for instruction and assessment will be provided along with preliminary results documenting the effectiveness of their use in the classroom.
De Visscher, Alice; Noël, Marie-Pascale; De Smedt, Bert
2016-12-01
Arithmetic facts, in particular multiplication tables, are thought to be stored in long-term memory and to be interference prone. At least two representations underpinning these arithmetic facts have been suggested: a physical representation of the digits and a numerical magnitude representation. We hypothesized that both representations are possible sources of interference that could explain individual differences in multiplication fact performance and/or in strategy use. We investigated the specificity of these interferences on arithmetic fact retrieval and explored the relation between interference and performance on the different arithmetic operations and on general mathematics achievement. Participants were 79 fourth-grade children (Mage=9.6 years) who completed a products comparison and a multiplication production task with verbal strategy reports. Performances on a speeded calculation test including the four operations and on a general mathematics achievement test were also collected. Only the interference coming from physical representations was a significant predictor of the performance across multiplications. However, both the magnitude and physical representations were unique predictors of individual differences in multiplication. The frequency of the retrieval strategy across multiplication problems and across individuals was determined only by the physical representation, which therefore is suggested as being responsible for memory storage issues. Interestingly, this impact of physical representation was not observed when predicting performance on subtraction or on general mathematical achievement. In contrast, the impact of the numerical magnitude representation was more general in that it was observed across all arithmetic operations and in general mathematics achievement. Copyright © 2016 Elsevier Inc. All rights reserved.
Covariant representations of subproduct systems
Viselter, Ami
2010-01-01
A celebrated theorem of Pimsner states that a covariant representation $T$ of a $C^*$-correspondence $E$ extends to a $C^*$-representation of the Toeplitz algebra of $E$ if and only if $T$ is isometric. This paper is mainly concerned with finding conditions for a covariant representation of a \\emph{subproduct system} to extend to a $C^*$-representation of the Toeplitz algebra. This framework is much more general than the former. We are able to find sufficient conditions, and show that in important special cases, they are also necessary. Further results include the universality of the tensor algebra, dilations of completely contractive covariant representations, Wold decompositions and von Neumann inequalities.
On the squeezed number states and their phase space representations
Albano, L [Universidad Simon Bolivar, Departamento de Fisica, Apartado Postal 89000, Caracas 1080-A (Venezuela); Mundarain, D F [Universidad Simon Bolivar, Departamento de Fisica, Apartado Postal 89000, Caracas 1080-A (Venezuela); Stephany, J [Universidad Simon Bolivar, Departamento de Fisica, Apartado Postal 89000, Caracas 1080-A (Venezuela)
2002-10-01
We compute the photon-number distribution, the Q({alpha}) distribution function and the wavefunctions in the momentum and position representation for a single mode squeezed number state using generating functions which allow one to obtain any matrix element in the squeezed number state representation from the matrix elements in the squeezed coherent state representation. For highly squeezed number states we discuss the previously unnoted oscillations which appear in the Q({alpha}) function. We also note that these oscillations can be related to the photon-number distribution oscillations and to the momentum representation of the wavefunction.
The endoscopic classification of representations orthogonal and symplectic groups
Arthur, James
2013-01-01
Within the Langlands program, endoscopy is a fundamental process for relating automorphic representations of one group with those of another. In this book, Arthur establishes an endoscopic classification of automorphic representations of orthogonal and symplectic groups G. The representations are shown to occur in families (known as global L-packets and A-packets), which are parametrized by certain self-dual automorphic representations of an associated general linear group GL(N). The central result is a simple and explicit formula for the multiplicity in the automorphic discrete spectrum of G
Tables of the principal unitary representations of Fedorov groups
Faddeyev, D K
1961-01-01
Tables of the Principal Unitary Representations of Fedorov Groups contains tables of all the principal representations of Fedorov groups from which all irreducible unitary representations can be obtained with the help of some standard operations. The work originated at a seminar on mathematical crystallography held in 1952-1953 at the Faculty of Mathematics and Mechanics of the Leningrad State University. The book is divided into two parts. The first part discusses the relation between the theory of representations and the generalized Fedorov groups in Shubnikov's sense. It shows that all un
Categorification and higher representation theory
Beliakova, Anna
2017-01-01
The emergent mathematical philosophy of categorification is reshaping our view of modern mathematics by uncovering a hidden layer of structure in mathematics, revealing richer and more robust structures capable of describing more complex phenomena. Categorified representation theory, or higher representation theory, aims to understand a new level of structure present in representation theory. Rather than studying actions of algebras on vector spaces where algebra elements act by linear endomorphisms of the vector space, higher representation theory describes the structure present when algebras act on categories, with algebra elements acting by functors. The new level of structure in higher representation theory arises by studying the natural transformations between functors. This enhanced perspective brings into play a powerful new set of tools that deepens our understanding of traditional representation theory. This volume exhibits some of the current trends in higher representation theory and the diverse te...
Sampling and Representation Complexity of Revenue Maximization
Dughmi, Shaddin; Han, Li; Nisan, Noam
2014-01-01
We consider (approximate) revenue maximization in auctions where the distribution on input valuations is given via "black box" access to samples from the distribution. We observe that the number of samples required -- the sample complexity -- is tightly related to the representation complexity of an approximately revenue-maximizing auction. Our main results are upper bounds and an exponential lower bound on these complexities.
On modular Galois representations modulo prime powers
Chen, Imin; Kiming, Ian; Wiese, Gabor
2013-01-01
. These notions of modularity are relative to a fixed level M. Using results of Hida we display a level-lowering result ("stripping-of-powers of p away from the level"): A mod pm strongly modular representation of some level Npr is always dc-weakly modular of level N (here, N is a natural number not divisible...
Representations of intercourse in American literature
Jensen, Kim Ebensgaard
2014-01-01
on theoretical notions from cognitive poetics, the present article assumes that literary representations of intercourse reflect and replicate in readers cognitive-cultural models of intercourse and the roles of, and power relations between, men and women therein. The analysis presented here is quantitative...
Complex Spectral Minutiae Representation For Fingerprint Recognition
Xu, Haiyun; Veldhuis, Raymond N.J.
2010-01-01
The spectral minutiae representation is designed for combining fingerprint recognition with template protection. This puts several constraints to the fingerprint recognition system: first, no relative alignment of two fingerprints is allowed due to the encrypted storage; second, a fixed-length featu
Value representations: a value based dialogue tool
Petersen, Marianne Graves; Rasmussen, Majken Kirkegaard
2011-01-01
Stereotypic presumptions about gender affect the design process, both in relation to how users are understood and how products are designed. As a way to decrease the influence of stereotypic presumptions in design process, we propose not to disregard the aspect of gender in the design process......, as the perspective brings valuable insights on different approaches to technology, but instead to view gender through a value lens. Contributing to this perspective, we have developed Value Representations as a design-oriented instrument for staging a reflective dialogue with users. Value Representations...
The bilingual brain: cerebral representation of languages.
Fabbro, F
2001-11-01
The present article deals with theoretical and experimental aspects of language representation in the multilingual brain. Two general approaches were adopted in the study of the bilingual brain. The study of bilingual aphasics allows us to describe dissociations and double dissociations between the different subcomponents of the various languages. Furthermore, symptoms peculiar to bilingual aphasia were reported (pathological mixing and switching and translations disorders) which allowed the correlation of some abilities specific to bilinguals with particular neurofunctional systems. Another approach to the study of the bilingual brain is of the experimental type, such as electrophysiological investigations (electrocorticostimulation during brain surgery and event-related potentials) and functional neuroanatomy studies (positron emission tomography and functional magnetic resonance imaging). Functional neuroanatomy studies investigated the brain representation of languages when processing lexical and syntactic stimuli and short stories. Neurophysiologic and neuroimaging studies evidenced a similar cerebral representation of L1 and L2 lexicons both in early and late bilinguals. The representation of grammatical aspects of languages seems to be different between the two languages if L2 is acquired after the age of 7, with automatic processes and correctness being lower than those of the native language. These results are in line with a greater representation of the two lexicons in the declarative memory systems, whereas morphosyntactic aspects may be organized in different systems according to the acquisition vs learning modality.
Cusped Wilson lines in symmetric representations
Correa, Diego H; Trancanelli, Diego
2015-01-01
We study the cusped Wilson line operators and Bremsstrahlung functions associated to particles transforming in the rank-$k$ symmetric representation of the gauge group $U(N)$ for ${\\cal N} = 4$ super Yang-Mills. We find the holographic D3-brane description for Wilson loops with internal cusps in two different limits: small cusp angle and $k\\sqrt{\\lambda}\\gg N$. This allows for a non-trivial check of a conjectured relation between the Bremsstrahlung function and the expectation value of the 1/2 BPS circular loop in the case of a representation other than the fundamental. Moreover, we observe that in the limit of $k\\gg N$, the cusped Wilson line expectation value is simply given by the exponential of the 1-loop diagram. Using group theory arguments, this eikonal exponentiation is conjectured to take place for all Wilson loop operators in symmetric representations with large $k$, independently of the contour on which they are supported.
Materials Driven Architectural Design and Representation
Kruse Aagaard, Anders
2015-01-01
This paper aims to outline a framework for a deeper connection between experimentally obtained material knowledge and architectural design. While materials and architecture in the process of realisation are tightly connected, architectural design and representation are often distanced from...... another role in relation to architectural production. It is, in this paper, the intention to point at material research as an active initiator in explorative approaches to architectural design methods and architectural representation. This paper will point at the inclusion of tangible and experimental...... material research in the early phases of architectural design and to that of the architectural set of tools and representation. The paper will through use of existing research and the author’s own material research and practice suggest a way of using a combination of digital drawing, digital fabrication...
Representation of Spin Group Spin(p, q)
无
2007-01-01
The representation (&)(p, q) of spin group Spin(p, q) in any dimensional space is given by induction, and the relation between two representations, which are obtained in two kinds of inductions from Spin(p, q) to Spin(p + 1, q + 1)are studied.
An Axiomatic, Unified Representation of Biosystems and Quantum Dynamics
Baianu, I
2004-01-01
An axiomatic representation of system dynamics is introduced in terms of categories, functors, organismal supercategories, limits and colimits of diagrams. Specific examples are considered in Complex Systems Biology, such as ribosome biogenesis and Hormonal Control in human subjects. "Fuzzy" Relational Structures are also proposed for flexible representations of biological system dynamics and organization.
A General Representation Theorem for Integrated Vector Autoregressive Processes
Franchi, Massimo
We study the algebraic structure of an I(d) vector autoregressive process, where d is restricted to be an integer. This is useful to characterize its polynomial cointegrating relations and its moving average representation, that is to prove a version of the Granger representation theorem valid...... for I(d) vector autoregressive processes...
29 CFR 452.128 - Under-strength representation.
2010-07-01
... 29 Labor 2 2010-07-01 2010-07-01 false Under-strength representation. 452.128 Section 452.128 Labor Regulations Relating to Labor OFFICE OF LABOR-MANAGEMENT STANDARDS, DEPARTMENT OF LABOR LABOR... representation. A local union may elect fewer delegates than it is permitted under the union constitution as long...
49 CFR 511.72 - Authority for representation.
2010-10-01
... 49 Transportation 6 2010-10-01 2010-10-01 false Authority for representation. 511.72 Section 511.72 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC... Conduct § 511.72 Authority for representation. Any individual acting in a representative capacity in any...
Representations of commonsense knowledge
Davis, Ernest
1990-01-01
Representations of Commonsense Knowledge provides a rich language for expressing commonsense knowledge and inference techniques for carrying out commonsense knowledge. This book provides a survey of the research on commonsense knowledge.Organized into 10 chapters, this book begins with an overview of the basic ideas on artificial intelligence commonsense reasoning. This text then examines the structure of logic, which is roughly analogous to that of a programming language. Other chapters describe how rules of universal validity can be applied to facts known with absolute certainty to deduce ot
Boot, Inge; Pecher, Diane
2011-01-01
In the present study we investigated whether the mental representation of the concept categories is represented by the container image schema (Lakoff & Johnson, 1980). In two experiments participants decided whether two pictures were from the same category (animal or vehicle). Pictures were presented inside or outside a frame that should activate the container schema. We found that performance to pictures was influenced by the frame in congruence with the metaphorical mapping (same category—inside bounded region; different category—not in same bounded region). These results show that the concept categories is metaphorically represented by containers.
Márcia Ondina Vieira Ferreira
2008-06-01
Full Text Available Analisam-se as representações sobre relações de gênero na educação e as trajetórias sindicais de diretoras/es do 24º Núcleo do CPERS/SINDICATO (Centro dos Professores do Estado do Rio Grande do Sul - Sindicato dos Trabalhadores em Educação. No referencial, recuperam-se aspectos da constituição da docência que interferem nas representações sobre esse ofício: feminização, proletarização e sindicalização, bem como a fragilidade, nos sindicatos e na academia, das discussões sobre o impacto das relações de gênero no trabalho docente. Em termos empíricos, examinam-se: a escolarização dos sujeitos como estratégia familiar de ascensão social; as resistências a abordar o tema das relações de gênero; a tendência das mulheres a criticar comportamentos masculinos, em classe e na militância; e a dos homens de valorizar a atividade feminina.This paper analyzes the representations of gender relations in education and the trajectories of CPERS/SINDICATO (the Teachers' Union - 24th Section board members. It takes up discussions on issues such as teaching feminization, proletariatization, and union affiliation and emphasizes that the discussions on the impact of gender relations on the teachers' work carried out at unions and the academia are characterized by a certain weakness. The following aspects are examined as well: schooling as a familial strategy of social ascension, resistance to talking about gender relations, tendency of women to criticize male behavior in class and in labor activism, and the tendency of men to valorize female activities.
A thesaurus for a neural population code.
Ganmor, Elad; Segev, Ronen; Schneidman, Elad
2015-09-08
Information is carried in the brain by the joint spiking patterns of large groups of noisy, unreliable neurons. This noise limits the capacity of the neural code and determines how information can be transmitted and read-out. To accurately decode, the brain must overcome this noise and identify which patterns are semantically similar. We use models of network encoding noise to learn a thesaurus for populations of neurons in the vertebrate retina responding to artificial and natural videos, measuring the similarity between population responses to visual stimuli based on the information they carry. This thesaurus reveals that the code is organized in clusters of synonymous activity patterns that are similar in meaning but may differ considerably in their structure. This organization is highly reminiscent of the design of engineered codes. We suggest that the brain may use this structure and show how it allows accurate decoding of novel stimuli from novel spiking patterns.
Knowledge representation with SOA
Daniela Gotseva
2013-01-01
Full Text Available This paper addresses the problem of supporting the software development process through the artificial intelligence. The expert systems could advise the Domain Engineer in programming without the detailed experience in programming languages. He will use and integrate, with the help of deductive database and domain knowledge, the previously developed software components to new complex functionalities. The objective of this document is to provide the knowledge representation about atomic Web Services which will be registered as the facts in the deductive database. The author proposes to use the decision rules in decision tables for representing the service model which consists of semantic specification, interface description, service quality (QoS, non-functional properties. Also the use of Domain Specific Languages (DSL for modeling Domain Engineers re-quests to the expert system will be considered within this document. As the illustrative use case for described knowledge representation the author proposes the domain of SOA-based geographic information systems (GIS which represent a new branch of information and communication technologies.
Petersen, Jakob; Pollak, Eli
2015-12-01
One of the challenges facing on-the-fly ab initio semiclassical time evolution is the large expense needed to converge the computation. In this paper, we suggest that a significant saving in computational effort may be achieved by employing a semiclassical initial value representation (SCIVR) of the quantum propagator based on the Heisenberg interaction representation. We formulate and test numerically a modification and simplification of the previous semiclassical interaction representation of Shao and Makri [J. Chem. Phys. 113, 3681 (2000)]. The formulation is based on the wavefunction form of the semiclassical propagation instead of the operator form, and so is simpler and cheaper to implement. The semiclassical interaction representation has the advantage that the phase and prefactor vary relatively slowly as compared to the "standard" SCIVR methods. This improves its convergence properties significantly. Using a one-dimensional model system, the approximation is compared with Herman-Kluk's frozen Gaussian and Heller's thawed Gaussian approximations. The convergence properties of the interaction representation approach are shown to be favorable and indicate that the interaction representation is a viable way of incorporating on-the-fly force field information within a semiclassical framework.
Petersen, Jakob; Pollak, Eli, E-mail: eli.pollak@weizmann.ac.il [Chemical Physics Department, Weizmann Institute of Science, 76100 Rehovot (Israel)
2015-12-14
One of the challenges facing on-the-fly ab initio semiclassical time evolution is the large expense needed to converge the computation. In this paper, we suggest that a significant saving in computational effort may be achieved by employing a semiclassical initial value representation (SCIVR) of the quantum propagator based on the Heisenberg interaction representation. We formulate and test numerically a modification and simplification of the previous semiclassical interaction representation of Shao and Makri [J. Chem. Phys. 113, 3681 (2000)]. The formulation is based on the wavefunction form of the semiclassical propagation instead of the operator form, and so is simpler and cheaper to implement. The semiclassical interaction representation has the advantage that the phase and prefactor vary relatively slowly as compared to the “standard” SCIVR methods. This improves its convergence properties significantly. Using a one-dimensional model system, the approximation is compared with Herman-Kluk’s frozen Gaussian and Heller’s thawed Gaussian approximations. The convergence properties of the interaction representation approach are shown to be favorable and indicate that the interaction representation is a viable way of incorporating on-the-fly force field information within a semiclassical framework.
Petersen, Jakob; Pollak, Eli
2015-12-14
One of the challenges facing on-the-fly ab initio semiclassical time evolution is the large expense needed to converge the computation. In this paper, we suggest that a significant saving in computational effort may be achieved by employing a semiclassical initial value representation (SCIVR) of the quantum propagator based on the Heisenberg interaction representation. We formulate and test numerically a modification and simplification of the previous semiclassical interaction representation of Shao and Makri [J. Chem. Phys. 113, 3681 (2000)]. The formulation is based on the wavefunction form of the semiclassical propagation instead of the operator form, and so is simpler and cheaper to implement. The semiclassical interaction representation has the advantage that the phase and prefactor vary relatively slowly as compared to the "standard" SCIVR methods. This improves its convergence properties significantly. Using a one-dimensional model system, the approximation is compared with Herman-Kluk's frozen Gaussian and Heller's thawed Gaussian approximations. The convergence properties of the interaction representation approach are shown to be favorable and indicate that the interaction representation is a viable way of incorporating on-the-fly force field information within a semiclassical framework.
Neural Representation. A Survey-Based Analysis of the Notion.
Vilarroya, Oscar
2017-01-01
The word representation (as in "neural representation"), and many of its related terms, such as to represent, representational and the like, play a central explanatory role in neuroscience literature. For instance, in "place cell" literature, place cells are extensively associated with their role in "the representation of space." In spite of its extended use, we still lack a clear, universal and widely accepted view on what it means for a nervous system to represent something, on what makes a neural activity a representation, and on what is re-presented. The lack of a theoretical foundation and definition of the notion has not hindered actual research. My aim here is to identify how active scientists use the notion of neural representation, and eventually to list a set of criteria, based on actual use, that can help in distinguishing between genuine or non-genuine neural-representation candidates. In order to attain this objective, I present first the results of a survey of authors within two domains, place-cell and multivariate pattern analysis (MVPA) research. Based on the authors' replies, and on a review of neuroscientific research, I outline a set of common properties that an account of neural representation seems to require. I then apply these properties to assess the use of the notion in two domains of the survey, place-cell and MVPA studies. I conclude by exploring a shift in the notion of representation suggested by recent literature.
Effective representations of the space of linear bounded operators
Vasco Brattka
2003-04-01
Full Text Available Representations of topological spaces by infinite sequences of symbols are used in computable analysis to describe computations in topological spaces with the help of Turing machines. From the computer science point of view such representations can be considered as data structures of topological spaces. Formally, a representation of a topological space is a surjective mapping from Cantor space onto the corresponding space. Typically, one is interested in admissible, i.e. topologically well-behaved representations which are continuous and characterized by a certain maximality condition. We discuss a number of representations of the space of linear bounded operators on a Banach space. Since the operator norm topology of the operator space is nonseparable in typical cases, the operator space cannot be represented admissibly with respect to this topology. However, other topologies, like the compact open topology and the Fell topology (on the operator graph give rise to a number of promising representations of operator spaces which can partially replace the operator norm topology. These representations reflect the information which is included in certain data structures for operators, such as programs or enumerations of graphs. We investigate the sublattice of these representations with respect to continuous and computable reducibility. Certain additional conditions, such as finite dimensionality, let some classes of representations collapse, and thus, change the corresponding graph. Altogether, a precise picture of possible data structures for operator spaces and their mutual relation can be drawn.
Symposium on Singularities, Representation of Algebras, and Vector Bundles
Trautmann, Günther
1987-01-01
It is well known that there are close relations between classes of singularities and representation theory via the McKay correspondence and between representation theory and vector bundles on projective spaces via the Bernstein-Gelfand-Gelfand construction. These relations however cannot be considered to be either completely understood or fully exploited. These proceedings document recent developments in the area. The questions and methods of representation theory have applications to singularities and to vector bundles. Representation theory itself, which had primarily developed its methods for Artinian algebras, starts to investigate algebras of higher dimension partly because of these applications. Future research in representation theory may be spurred by the classification of singularities and the highly developed theory of moduli for vector bundles. The volume contains 3 survey articles on the 3 main topics mentioned, stressing their interrelationships, as well as original research papers.
[The effect of goal framing on the activation of affective representations].
Takehashi, Hiroki; Karasawa, Kaori
2007-10-01
Guided by regulatory focus theory, this study examined the effects of goal framing on the subjective experience of affect and the accessibility of affective representations. Study I examined lay persons' beliefs concerning the relationship between goal framing and certain kinds of affective experiences. The results indicated that a promotion focus was associated with happiness and disappointment, whereas a prevention focus was associated with relaxation and tension. Study 2 examined the effect of goal framing on the activation of affective representations, and found that a promotion focus activated both gain-related representations (happy and disappointment) and loss-related representations (relaxation and tension), whereas a prevention focus activated only loss-related representations. These results suggest that goal framing activates particular affective representations, and the activated affective representations may influence the interpretation of positive or negative experiences. The discussion considered the function of the activation of affective representations as a mediator between goal framing and its cognitive and behavioral consequences.
Integral geometry and representation theory
Gel'fand, I M; Vilenkin, N Ya
1966-01-01
Generalized Functions, Volume 5: Integral Geometry and Representation Theory is devoted to the theory of representations, focusing on the group of two-dimensional complex matrices of determinant one.This book emphasizes that the theory of representations is a good example of the use of algebraic and geometric methods in functional analysis, in which transformations are performed not on the points of a space, but on the functions defined on it. The topics discussed include Radon transform on a real affine space, integral transforms in the complex domain, and representations of the group of comp
Going beyond representational anthropology
Winther, Ida Wentzel
an education. There is a close connection between: 1) The dream and the desire for education; 2) Mobility (away from the family, home and friends in a very young age for getting an education; 3) Transforming a new and unknown site and space into a known place, where one can make one-self at home ('home one......Going beyond representational anthropology: Re-presenting bodily, emotional and virtual practices in everyday life. Separated youngsters and families in Greenland Greenland is a huge island, with a total of four high-schools. Many youngsters (age 16-18) move far away from home in order to get...... transformation work into the young people and their families. In this presentation I want to screen two sequences from the film, in order to show and clarify how mobility and transformation are made and dealt with both from the youngsters’ and their parents’ perspectives, but in asynchronous loups. I want...
Linear recursive distributed representations.
Voegtlin, Thomas; Dominey, Peter F
2005-09-01
Connectionist networks have been criticized for their inability to represent complex structures with systematicity. That is, while they can be trained to represent and manipulate complex objects made of several constituents, they generally fail to generalize to novel combinations of the same constituents. This paper presents a modification of Pollack's Recursive Auto-Associative Memory (RAAM), that addresses this criticism. The network uses linear units and is trained with Oja's rule, in which it generalizes PCA to tree-structured data. Learned representations may be linearly combined, in order to represent new complex structures. This results in unprecedented generalization capabilities. Capacity is orders of magnitude higher than that of a RAAM trained with back-propagation. Moreover, regularities of the training set are preserved in the new formed objects. The formation of new structures displays developmental effects similar to those observed in children when learning to generalize about the argument structure of verbs.
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.
Preschool Children's Participation in Representational and Non-Representational Activities
Braswell, Gregory S.
2017-01-01
The present study examined representational and non-representational activities in which children in a Head Start classroom participated. This was an investigation from the perspective of cultural-historical activity theory of how components (e.g. artifacts and division of labour) of classroom activities vary across and within types of activities.…
On Maintenance of Inter-connectivity Among Multi-representations
WANG Yan-hui; MENG Hao; LIU Xiao-meng
2006-01-01
As the problems of conceptual and representational differences will arise among multi-representations, inter-connectivity maintenance among multi-representations exists as a foundational task in building multi-scale data model. Since the existing methods are still not satisfactory in practice, the inter-connectivity among multiple representations can be only achieved if the multi-scale model is capable of explicitly inter-relating them and dealing with their differences. So, this paper firstly explores the relation among multiple representations from the same entity, such as multi-semantic, multi-geometry, multi-attributes, hierarchical semantic relations and so on. Based on these, this paper proposes aggregation-based semantic hierarchical matching rules (ASHMR) as the basis of tackling inter-connectivity among multi-representations, and defines the available hierarchical semantic knowledge, namely semantically equal, semantically related and semantically irrelevant. According to different change among multi-representations from different types of objects, the applications and techniques of the corresponding hierarchy inter-connectivity matching criterion are explored. And taken the road intersections as examples, a case in point is given in details for describing the strategies of inter-connectivity maintenance, showing that this method is feasible to deal with inter-connectivity.
Continuum representations of cellular solids
Neilsen, M.K.
1993-09-01
Cellular materials consist of interconnected struts or plates which form cells. The struts or plates are constructed from a variety of metals, polymers, ceramics and wood products. Cellular materials are often used in impact limiters for shipping containers to protect the contents from accidental impact events. These materials exhibit a variety of complex behavior when subjected to crushing loads. This research focuses on the development of continuum representations of cellular solids that can be used in the finite element analysis of shipping container accidents. A significant portion of this work is the development of a new methodology to relate localized deformations to appropriate constitutive descriptions. This methodology provides the insight needed to select constitutive descriptions for cellular solids that capture the localized deformations that are observed experimentally. Constitutive relations are developed for two different cellular materials, aluminum honeycomb and polyurethane foam. These constitutive relations are based on plasticity and continuum damage theories. Plasticity is used to describe the permanent deformation exhibited by both aluminum honeycomb and polyurethane foam. Continuum damage is needed to capture the change in elastic parameters due to cracking of the polyurethane cell wall materials. The new constitutive description of polyurethane foam is implemented in both static and dynamic finite element codes, and analytical and numerical predictions are compared with available experimental data.
Congruence properties of induced representations
Mayer, Dieter; Momeni, Arash; Venkov, Alexei
In this paper we study representations of the projective modular group induced from the Hecke congruence group of level 4 with Selberg's character. We show that the well known congruence properties of Selberg's character are equivalent to the congruence properties of the induced representations. ...
Scientific Representation and Science Learning
Matta, Corrado
2014-01-01
In this article I examine three examples of philosophical theories of scientific representation with the aim of assessing which of these is a good candidate for a philosophical theory of scientific representation in science learning. The three candidate theories are Giere's intentional approach, Suárez's inferential approach and Lynch and…
Adjoint Functors and Representation Dimensions
Chang Chang XI
2006-01-01
We study the global dimensions of the coherent functors over two categories that are linked by a pair of adjoint functors. This idea is then exploited to compare the representation dimensions of two algebras. In particular, we show that if an Artin algebra is switched from the other, then they have the same representation dimension.
International agreements on commercial representation
Slanař, Jan
2014-01-01
The purpose of the thesis is to describe the possibilities for fixing the position of a company in the market through contracts for commercial representation with a focus to finding legal and economic impact on the company that contracted for exclusive representation.
Scientific Representation and Science Learning
Matta, Corrado
2014-01-01
In this article I examine three examples of philosophical theories of scientific representation with the aim of assessing which of these is a good candidate for a philosophical theory of scientific representation in science learning. The three candidate theories are Giere's intentional approach, Suárez's inferential approach and Lynch and…
String operator formalism and functional integral in holomorphic representation
Losev, A.; Morozov, A.; Rosly, A.; Shatashvili, S.
1989-01-05
We discuss the relation between the functional integral over open Riemann surfaces and the operator formalism on closed Riemann surfaces. The states in the latter formalism arise in the holomorphic representation of the functional integral.
Hierarchical Representation Learning for Kinship Verification.
Kohli, Naman; Vatsa, Mayank; Singh, Richa; Noore, Afzel; Majumdar, Angshul
2017-01-01
Kinship verification has a number of applications such as organizing large collections of images and recognizing resemblances among humans. In this paper, first, a human study is conducted to understand the capabilities of human mind and to identify the discriminatory areas of a face that facilitate kinship-cues. The visual stimuli presented to the participants determine their ability to recognize kin relationship using the whole face as well as specific facial regions. The effect of participant gender and age and kin-relation pair of the stimulus is analyzed using quantitative measures such as accuracy, discriminability index d' , and perceptual information entropy. Utilizing the information obtained from the human study, a hierarchical kinship verification via representation learning (KVRL) framework is utilized to learn the representation of different face regions in an unsupervised manner. We propose a novel approach for feature representation termed as filtered contractive deep belief networks (fcDBN). The proposed feature representation encodes relational information present in images using filters and contractive regularization penalty. A compact representation of facial images of kin is extracted as an output from the learned model and a multi-layer neural network is utilized to verify the kin accurately. A new WVU kinship database is created, which consists of multiple images per subject to facilitate kinship verification. The results show that the proposed deep learning framework (KVRL-fcDBN) yields the state-of-the-art kinship verification accuracy on the WVU kinship database and on four existing benchmark data sets. Furthermore, kinship information is used as a soft biometric modality to boost the performance of face verification via product of likelihood ratio and support vector machine based approaches. Using the proposed KVRL-fcDBN framework, an improvement of over 20% is observed in the performance of face verification.
Student Representation in University Decision Making: Good Reasons, a New Lens?
Luescher-Mamashela, Thierry M.
2013-01-01
This article outlines the main cases for and related objections against student representation in university governance found in the relevant literature, and proposes a way in which variations in student representation within institutions may be understood and justified. It contextualises the modern origins of student representation in the…
Higher-dimensional Higgs Representations in SGUT models
Aranda, Alfredo; Rojas, Alma D
2010-01-01
Supersymmetric Grand Unified Theories (SGUTs) have achieved some degree of success, already present in the minimal models (with SU(5) or SO(10)). However, there are open problems that suggest the need to incorporate more elaborate constructions, specifically the use of higher-dimensional representations in the Higgs sector. For example, a $45$ representation of SU(5) is often included to obtain correct mass relations for the first and second families of d-type quarks and leptons. When one adds these higher-dimensional Higgs representations one must verify the cancellation of anomalies associated to their fermionic partners. One possible choice, free of anomalies, include both $45,\\overline{45}$ representations to cancel anomalies. We review the necessary conditions for the cancellation of anomalies and discuss the different possibilities for supersymmetric SU(5) models. Alternative anomaly-free combinations of Higgs representations, beyond the usual vectorlike choice, are identified, and it is shown that thei...
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.
Fuzzy Morphological Polynomial Image Representation
Chin-Pan Huang
2010-01-01
Full Text Available A novel signal representation using fuzzy mathematical morphology is developed. We take advantage of the optimum fuzzy fitting and the efficient implementation of morphological operators to extract geometric information from signals. The new representation provides results analogous to those given by the polynomial transform. Geometrical decomposition of a signal is achieved by windowing and applying sequentially fuzzy morphological opening with structuring functions. The resulting representation is made to resemble an orthogonal expansion by constraining the results of opening to equate adapted structuring functions. Properties of the geometric decomposition are considered and used to calculate the adaptation parameters. Our procedure provides an efficient and flexible representation which can be efficiently implemented in parallel. The application of the representation is illustrated in data compression and fractal dimension estimation temporal signals and images.
On modular Galois representations modulo prime powers
Chen, Imin; Wiese, Gabor
2011-01-01
We study modular Galois representations mod $p^m$. We show that there are three progressively weaker notions of modularity for a Galois representation mod $p^m$: we have named these `strongly', `weakly', and `dc-weakly' modular. Here, `dc' stands for `divided congruence' in the sense of Katz and Hida. These notions of modularity are relative to a fixed level $M$. Using results of Hida we display a `stripping-of-powers of $p$ away from the level' type of result: A mod $p^m$ strongly modular representation of some level $Np^r$ is always dc-weakly modular of level $N$ (here, $N$ is a natural number not divisible by $p$). We also study eigenforms mod $p^m$ corresponding to the above three notions. Assuming residual irreducibility, we utilize a theorem of Carayol to show that one can attach a Galois representation mod $p^m$ to any `dc-weak' eigenform, and hence to any eigenform mod $p^m$ in any of the three senses. We show that the three notions of modularity coincide when $m=1$ (as well as in other, particular ca...
Archival Representation in the Digital Age
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…
Archival Representation in the Digital Age
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…
Baudrit, C
2005-10-15
, and it is more natural to use intervals. However, the available information is often richer than an interval but less rich than a probability distribution. In practice, while information regarding variability is best conveyed using probability distributions, information regarding impreciseness is more faithful conveyed using probability families encoded either by p-boxes (lower and upper cumulative distribution functions) or by possibility distributions (also called fuzzy intervals) or yet by random intervals using the belief functions of Dempster-Shafer. The first objective of this work is to propose practical representation methods according to available information regarding model parameters by using possibility, probability and random sets. The second one is to propose different methods for propagating variability and impreciseness information through risk model by trying to take into account dependency between model parameters. Lastly, these alternative methods are tested on simplified real cases, with a view to provide useful inputs for the decision-making process: - Dose calculation: Transfer of a radioactive pollutant (strontium) from the deposit to man, through the consumption of food (cow's milk). - Toxic risk related to the accidental spill of trichloroethylene (TCE) into an aquifer (semi-analytical model). - Risk for health related to grounds polluted by lead due to the presence of factories. (author)
Factorization of stochastic maps using the Stinespring representations
2016-01-01
In this work, we investigate the existence of a factorization for a unital completely positive map, between non-commutative probability space which do not change the expectation values of the events. These maps are called in literature stochastic maps. Using the Stinespring representations of completely positive map and assuming the existence of anti-unitary operator on Hilbert space related to these representations which satisfying some modular relations, we prove that stochastic maps with a...
Islam and Media Representations
Mohamed Bensalah
2006-04-01
Full Text Available For the author of this article, the media’s treatment of Islam has raised numerous polymorphous questions and debates. Reactivated by the great scares of current events, the issue, though an ancient one, calls many things into question. By way of introduction, the author tries to analyse the complex processes of elaboration and perception of the representations that have prevailed during the past century. In referring to the semantic decoding of the abundant colonial literature and iconography, the author strives to translate the extreme xenophobic tensions and the identity crystallisations associated with the current media orchestration of Islam, both in theWest and the East. He then evokes the excesses of the media that are found at the origin of many amalgams wisely maintained between Islam, Islamism and Islamic terrorism, underscoring their duplicity and their willingness to put themselves, consciously, in service to deceivers and directors of awareness, who are very active at the heart of the politico-media sphere. After levelling a severe accusation against the harmful drifts of the media, especially in times of crisis and war, the author concludes by asserting that these tools of communication, once they are freed of their masks and invective apparatuses, can be re-appropriated by new words and bya true communication between peoples and cultures.
Social Representations of Responsibility in Guatemalan Students
Humberto Emilio Aguilera Arévalo
2010-07-01
Full Text Available The responsibility is a key concept in the twentieth century because it establishes a connection between the individual and society. Recent studies analyze the responsibility as a relational concept that connects the individual to an event and its outcomes. In that sense, the responsibility may be linked to Markova perspective on dialogicality and social representations because it activates the Ego-Alter-Object dynamic: being responsible for something (Ego toward someone (Alter, and in relation to an instance (object. This paper analyzes the social representations of responsibility in a sample of 296 university students from Guatemala, who answered six stimulus words I Responsible, I Irresponsible, Responsible Guatemalan, Irresponsible Guatemalan, Responsible European and Irresponsible European, using the natural semantic networks technique. Subsequently two questionnaires were made; one about responsibility and irresponsibility on a personal, in group and out group level, based on semantic networks obtained. Finally, factor analysis and hierarchical cluster analysis were made.
Ergonomic risk: social representations of dental students
Luana Kelle Batista Moura
2014-01-01
Full Text Available Objective: To learn the social representations of ergonomic risk prepared by dental students. Methodology: This exploratory study, subsidized the Theory of Social Representations, with 64 dental students of an educational institution, by means of interviews. The data were processed in Alceste4.8 and lexical analysis done by the descending hierarchical classification. Results: In two categories: knowledge about exposure to ergonomic risk end attitude of students on preventing and treating injuries caused by repetitive motion. For students, the ergonomic risk is related to the attitude in the dental office. Conclusion: Prevention of ergonomic risk for dental students has not been incorporated as a set of necessary measures for their health and the patients, to prevent ergonomic hazards that can result in harm to the patient caused by work-related musculoskeletal disorder, which is reflected in a lower quality practice.
Representations of partial derivatives in thermodynamics
Thompson, John R.; Manogue, Corinne A.; Roundy, David J.; Mountcastle, Donald B.
2012-02-01
One of the mathematical objects that students become familiar with in thermodynamics, often for the first time, is the partial derivative of a multivariable function. The symbolic representation of a partial derivative and related quantities present difficulties for students in both mathematical and physical contexts, most notably what it means to keep one or more variables fixed while taking the derivative with respect to a different variable. Material properties are themselves written as partial derivatives of various state functions (e.g., compressibility is a partial derivative of volume with respect to pressure). Research in courses at the University of Maine and Oregon State University yields findings related to the many ways that partial derivatives can be represented and interpreted in thermodynamics. Research has informed curricular development that elicits many of the difficulties using different representations (e.g., geometric) and different contexts (e.g., connecting partial derivatives to specific experiments).
HU Li-Yun; FAN Hong-Yi
2008-01-01
By virtue of the Weyl correspondence and based on the the technique of integration within an ordered product of operators, we show under what condition the superoperator's Kraus representation ρ'=∑μAμρAμ can be deformed as ρ' = (1/π) f d2αB(α)D(α)pD (α), where D(α) is the displacement operator, B(α) is a probability density related to the classical Weft correspondence of Aμ. An alternate discussion by using the entangled state representation and through a quantum teleportation process is also presented.
Logging data representation based on XML
无
2007-01-01
As an open standard of data representation, XML breathes new energy to the Web application and the network computing. The development, advantage and status of XML and some standards relating to XML are reviewed. In addition, the authors put forward a method representing logging data and using UML language to establish the conceptual and logical model of logging data; using a logging data, explain how to establish the model as well as how to use XML to display and process geology data.
Sparse representations for radar with Matlab examples
Knee, Peter
2012-01-01
Although the field of sparse representations is relatively new, research activities in academic and industrial research labs are already producing encouraging results. The sparse signal or parameter model motivated several researchers and practitioners to explore high complexity/wide bandwidth applications such as Digital TV, MRI processing, and certain defense applications. The potential signal processing advancements in this area may influence radar technologies. This book presents the basic mathematical concepts along with a number of useful MATLAB® examples to emphasize the practical imple
Thermal Operator Representation of Finite Temperature Graphs
Brandt, Fernando T.; Das, Ashok; Espinosa, Olivier; Frenkel, Josif; Perez, Silvana
2005-01-01
Using the mixed space representation (t,p) in the context of scalar field theories, we prove in a simple manner that the Feynman graphs at finite temperature are related to the corresponding zero temperature diagrams through a simple thermal operator, both in the imaginary time as well as in the real time formalisms. This result is generalized to the case when there is a nontrivial chemical potential present. Several interesting properties of the thermal operator are also discussed.
Irreducible representations of Birman-Wenzl algebras
潘峰
1995-01-01
Irreducible representations of Birman-Wenzl algebras are constructed by using the induced representation and the linear equation method. Self-adjoint representations of Birman-Wenzl algebras Cf (r, q) with f≤4 are presented.
From Local to Global Additive Representation
Wakker, P.P.; Chateauneuf, A.
1993-01-01
This paper studies continuous additive representations of transitive preferences on connected subdomains of product sets. Contrary to what has sometimes been thought, local additive representability does not imply global additive representability. It is shown that the result can nevertheless be
From local to global additive representation
A. Chateauneuf (Alain); P.P. Wakker (Peter)
1993-01-01
textabstractThis paper studies continuous additive representations of transitive preferences on connected subdomains of product sets. Contrary to what has sometimes been thought, local additive representability does not imply global additive representability. It is shown that the result can
Functional Representations for Fock Superalgebras
Kupsch, J; Kupsch, Joachim; Smolyanov, Oleg G.
1997-01-01
The Fock space of bosons and fermions and its underlying superalgebra are represented by algebras of functions on a superspace. We define Gaussian integration on infinite dimensional superspaces, and construct superanalogs of the classical function spaces with a reproducing kernel -- including the Bargmann-Fock representation -- and of the Wiener-Segal representation. The latter representation requires the investigation of Wick ordering on Z2-graded algebras. As application we derive a Mehler formula for the Ornstein-Uhlenbeck semigroup on the Fock space.
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.
Representation of identities and the politics of representation in cognition
Kanavillil Rajagopalan
2001-02-01
Full Text Available
In this paper, I make a plea for viewing representation as first and foremost a political matter. I argue that by so doing we may avoid the many of pitfalls of contemporary theories of cognition as they attempt to tackle the issue of representation. Most of these problems have to do with the fact that representation is treated exclusively as a mimetic or theatrical question. The fact of the matter is however that representation also has a political dimension. Indeed it has always had this political dimension which, counterintuitive though it may seem at first glimpse, manifests itself even in very the attempt to aestheticise the whole issue of representation (as in some versions of postmodernism or to deny its role altogether as a tertium quid between the external world and the cognising mind (as in contemporary neo-pragmatism. I also contend that, by recognising the political nature of representation, we also pave the way for endorsing the thesis that the mind is a social construct, thereby taking some steam out of the thesis of "mind-brain identity" (so-called "identity theory of mind".
Rosana Machin
2009-12-01
Full Text Available O trabalho analisa as representações de trabalhadores portuários avulsos do Porto de Santos-SP acerca das condições de trabalho, da relação trabalho-saúde e das estratégias adotadas para o cuidado em saúde a partir da perspectiva de gênero e das masculinidades. A pesquisa de natureza qualitativa desenvolveu-se na área de abrangência do Porto de Santos-SP. Foram entrevistados representantes de diferentes categorias de trabalhadores portuários, totalizando 13 entrevistas. O Porto é descrito pelos trabalhadores portuários como local perigoso, com grande ocorrência de acidentes. Eles atribuem esse risco à organização do trabalho e às condições muito heterogêneas sob as quais ele é realizado cotidianamente. As transformações no contexto imediato do trabalho portuário, produzidas nas últimas décadas, trazem implicações acerca dos padrões de adoecimento e sofrimento dessa população específica, ao mesmo tempo em que exigem paulatina (reprodução de valores e significados sobre ser homem e ser trabalhador portuário.This study analyses the representations of individual dock workers at the Port of Santos (state of São Paulo concerning working conditions, the relation between work and health, and also the adopted health care strategies from the perspective of gender and masculinities. Qualitative research was developed and a total of 13 interviews were conducted with representatives from different categories of dock workers. The Port is described by the workers as a dangerous place, where accidents occur very frequently. They attribute this risk to the organization of labor and to the very heterogeneous conditions in which it is conducted on a daily basis. The transformations that happened in the past decades in the immediate context of work on the docks have implications regarding the patterns of illness and suffering of this specific population; at the same time, they demand the gradual (reproduction of values and
(Self)-representations on youtube
Simonsen, Thomas Mosebo
This paper examines forms of self-representation on YouTube with specific focus on Vlogs (Video blogs). The analytical scope of the paper is on how User-generated Content on YouTube initiates a certain kind of audiovisual representation and a particular interpretation of reality that can...... be distinguished within Vlogs. This will be analysed through selected case studies taken from a representative sample of empirically based observations of YouTube videos. The analysis includes a focus on how certain forms of representation can be identified as representations of the self (Turkle 1995, Scannell...... 1996, Walker 2005) and further how these forms must be comprehended within a context of technological constrains, institutional structures and social as well as economical practices on YouTube (Burgess and Green 2009, Van Dijck 2009). It is argued that these different contexts play a vital part...
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.
Semantic Knowledge Representation (SKR) API
U.S. Department of Health & Human Services — The SKR Project was initiated at NLM in order to develop programs to provide usable semantic representation of biomedical free text by building on resources...
Integral representation of Skorokhod reflection
Anantharam, Venkat
2010-01-01
We show that a certain integral representation of the one-sided Skorokhod reflection of a continuous bounded variation function characterizes the reflection in that it possesses a unique maximal solution which solves the Skorokhod reflection problem.
Probability representation of classical states
Man'ko, OV; Man'ko, [No Value; Pilyavets, OV
2005-01-01
Probability representation of classical states described by symplectic tomograms is discussed. Tomographic symbols of classical observables which are functions on phase-space are studied. Explicit form of kernel of commutative star-product of the tomographic symbols is obtained.
Mental Representations in Art Discourse
Katja Sudec
2014-03-01
Full Text Available The paper starts by examining the content included in the museum environment, where I write about the type of relations that emerge in a museum or artistic setting. This is followed by an observation of a social act (socialising and a chapter on the use of food in an artistic venue. At the end, I address art education via the format that I developed at the 6th Berlin Biennale. This is followed by an overview of the cognitive model of the fort-da game based on Freud’s theory via two discourse models. Here, I address discourse on art works in the form of a lecture or reading, where the art space is fictitiously present, and then move on to discuss discourse on art works in real, “present” art space. This is followed by a section on actions (Handlungen in German and methods supporting the fort-da model. The last part of the article examines the issue of “mental representations”, defining and explaining the function of mental representations with regard to the target audience of the blind and visually impaired.
Hermann Weyl and Representation Theory
2016-12-01
Weyl was a universal mathematician whose fundamental contributionsto mathematics encompassed all areas, and provideda unification seldom seen. His work on the theory ofLie groups was motivated by his life-long interest in quantummechanics and relativity. When Weyl entered Lie theory,it mostly focussed on the infinitesimal, and he strove to bringin a global perspective. Time and again, Weyl’s ideas arisingin one context have been adapted and applied to wholly newcontexts. In 1925–26, Weyl wrote four epochal papers in representationtheory of Lie groups which solved fundamentalproblems, and also gave birth to the subject of harmonic analysisof semisimple Lie groups. In these papers, Weyl provedcomplete reducibility theorems and introduced many techniqueswhich have become the standard way to study representationsof Lie groups and their various generalizationsin the last seven decades. Weyl’s work covers several parts ofmathematics, as well as parts of physics. In this article, wediscuss mainly his contributions to the representation theoryof Lie groups via the four papers mentioned above.
Number line representations of fractions
Behr, Merlyn J.; Bright, George W.; Wachsmuth, Ipke; Wagner, Sigrid
1982-01-01
The study explored students' interpretations of representations of fractions on number lines and the effect of instruction on those interpretations. Subjects were five fourth-graders, and instruction was a four-day unit on the use of number lines. A 16-item, multiple-choice pre- and posttest was used along with videotaped interviews. Performance improved except when students had to associate a reduced fraction symbol with an equivalent, unreduced fraction representation on a number line. The ...
The Fifth Mode of Representation
Behrendt, Poul; Krogh Hansen, Per
2011-01-01
“The fifth mode of representation: Ambiguous voices in unreliable third person narration”. Sammen med Poul Behrendt. In Per Krogh Hansen, Stefan Iversen, Henrik Skov Nielsen og Rolf Reitan (red.): Strange Voices. Walter de Gruyter, Berlin & New York......“The fifth mode of representation: Ambiguous voices in unreliable third person narration”. Sammen med Poul Behrendt. In Per Krogh Hansen, Stefan Iversen, Henrik Skov Nielsen og Rolf Reitan (red.): Strange Voices. Walter de Gruyter, Berlin & New York...
Fermionic Sum Representations for Conformal Field Theory Characters
Kedem, R; McCoy, B M; Melzer, E
1993-01-01
We present sum representations for all characters of the unitary Virasoro minimal models. They can be viewed as fermionic companions of the Rocha-Caridi sum representations, the latter related to the (bosonic) Feigin-Fuchs-Felder construction. We also give fermionic representations for certain characters of the general $(G^{(1)})_k \\times (G^{(1)})_l \\over (G^{(1)})_{k+l}}$ coset conformal field theories, the non-unitary minimal models ${\\cal M}(p,p+2)$ and ${\\cal M}(p,kp+1)$, the $N$=2 superconformal series, and the $\\ZZ_N$-parafermion theories, and relate the $q\\to 1$ behaviour of all these fermionic sum representations to the thermodynamic Bethe Ansatz.
Uncertainty representation of grey numbers and grey sets.
Yang, Yingjie; Liu, Sifeng; John, Robert
2014-09-01
In the literature, there is a presumption that a grey set and an interval-valued fuzzy set are equivalent. This presumption ignores the existence of discrete components in a grey number. In this paper, new measurements of uncertainties of grey numbers and grey sets, consisting of both absolute and relative uncertainties, are defined to give a comprehensive representation of uncertainties in a grey number and a grey set. Some simple examples are provided to illustrate that the proposed uncertainty measurement can give an effective representation of both absolute and relative uncertainties in a grey number and a grey set. The relationships between grey sets and interval-valued fuzzy sets are also analyzed from the point of view of the proposed uncertainty representation. The analysis demonstrates that grey sets and interval-valued fuzzy sets provide different but overlapping models for uncertainty representation in sets.
Invariant properties of representations under cleft extensions
2007-01-01
The main aim of this paper is to give the invariant properties of representations of algebras under cleft extensions over a semisimple Hopf algebra. Firstly, we explain the concept of the cleft extension and give a relation between the cleft extension and the crossed product which is the approach we depend upon. Then, by making use of them, we prove that over an algebraically closed field k, for a finite dimensional Hopf algebra H which is semisimple as well as its dual H*, the representation type of an algebra is an invariant property under a finite dimensional H-cleft extension . In the other part, we still show that over an arbitrary field k, the Nakayama property of a k-algebra is also an invariant property under an H -cleft extension when the radical of the algebra is H-stable.
Representations of the infinite symmetric group
Borodin, Alexei
2016-01-01
Representation theory of big groups is an important and quickly developing part of modern mathematics, giving rise to a variety of important applications in probability and mathematical physics. This book provides the first concise and self-contained introduction to the theory on the simplest yet very nontrivial example of the infinite symmetric group, focusing on its deep connections to probability, mathematical physics, and algebraic combinatorics. Following a discussion of the classical Thoma's theorem which describes the characters of the infinite symmetric group, the authors describe explicit constructions of an important class of representations, including both the irreducible and generalized ones. Complete with detailed proofs, as well as numerous examples and exercises which help to summarize recent developments in the field, this book will enable graduates to enhance their understanding of the topic, while also aiding lecturers and researchers in related areas.
Representations built from a true geographic database
Bodum, Lars
2005-01-01
the whole world in 3d and with a spatial reference given by geographic coordinates. Built on top of this is a customised viewer, based on the Xith(Java) scenegraph. The viewer reads the objects directly from the database and solves the question about Level-Of-Detail on buildings, orientation in relation...... a representation based on geographic and geospatial principles. The system GRIFINOR, developed at 3DGI, Aalborg University, DK, is capable of creating this object-orientation and furthermore does this on top of a true Geographic database. A true Geographic database can be characterized as a database that can cover...... to terrain and rendering of the model. All this is done in something very close to real-time. GRIFINOR is at the moment working within a limited edition of the world. Only a few classes have been selected for representation in GRIFINOR. These are buildings, cadastre, trees, grass, roads. This paper...
Representation and Imperialism in Edward Said
Bruno Sciberras de Carvalho
2010-12-01
Full Text Available Based on the idea that culture and identities involve a politically built process, the importance of the concepts of representation and imperialism in the work of Edward Said is discussed. The article analyses two of the author’s general proposals. Firstly, the thesis of the centrality of cultural dimension in political relations, which leads to the review of postulates that consider culture as a mere reflection of a phenomena seen as essential or as a sphere isolated from the power practices. Secondly, the study examines how the author’s conception of imperialism is used as a means of identification that keep structures of authority and hegemony, which, in turn, may be defied by processes of resistance. Finally, the validity of the open character of Said’s political theory is debated, which encompasses both the power of representations and an action of political questioning.
SUBJECTIVITY: SOCIAL REPRESENTATION OF THE FAMILY
Lourdete Rejane Ferro Zago
2013-09-01
Full Text Available The family, first family group of human beings, is the collective dimension of human existence and becomes responsible for the formation of the first social identity, as well as the constitution of subjectivity. Subjectivity is the inner world of each and every human being. This inner world is made up of emotions, feelings and thoughts. It is through this inner world that the individual relates to the social world, appointed by the outside world. This relationship follows the individual characteristics that mark the individual as unique, originated in shaping the individual, when they built the knowledge and beliefs. social representation as a form of knowledge, socially elaborated, shared with a practical purpose, contributing to the construction of a common reality to a social group. Is thus built up the social representation of the family.
Two-vector representation of a nondepolarizing Mueller matrix
Gil, José J.; San José, Ignacio
2016-09-01
A geometric view of the polarimetric properties of a nondepolarizing medium is presented by means of a pair of vectors in the Poincaré sphere. An alternative representation constituted by a set of vectors contained in the equatorial plane of the Poincaré sphere is also defined and interpreted. The analyses of the magnitudes and relative orientations of the constitutive vectors of such simple representations allow for a classification of nondepolarizing media.
Representations of the Schroedinger group and matrix orthogonal polynomials
Vinet, Luc [Centre de recherches mathematiques, Universite de Montreal, CP 6128, succ. Centre-ville, Montreal, QC H3C 3J7 (Canada); Zhedanov, Alexei, E-mail: luc.vinet@umontreal.ca, E-mail: zhedanov@fti.dn.ua [Donetsk Institute for Physics and Technology, Donetsk 83114 (Ukraine)
2011-09-02
The representations of the Schroedinger group in one space dimension are explicitly constructed in the basis of the harmonic oscillator states. These representations are seen to involve matrix orthogonal polynomials in a discrete variable that have Charlier and Meixner polynomials as building blocks. The underlying Lie-theoretic framework allows for a systematic derivation of the structural formulas (recurrence relations, difference equations, Rodrigues' formula, etc) that these matrix orthogonal polynomials satisfy. (paper)
Beyond Natural Numbers: Negative Number Representation in Parietal Cortex
Blair, Kristen P.; Rosenberg-Lee, Miriam; Tsang, Jessica M.; Schwartz, Daniel L.; Menon, Vinod
2012-01-01
Unlike natural numbers, negative numbers do not have natural physical referents. How does the brain represent such abstract mathematical concepts? Two competing hypotheses regarding representational systems for negative numbers are a rule-based model, in which symbolic rules are applied to negative numbers to translate them into positive numbers when assessing magnitudes, and an expanded magnitude model, in which negative numbers have a distinct magnitude representation. Using an event-relate...
Implicit body representations and the conscious body image.
Longo, M. R.; Haggard, P.
2012-01-01
Recent studies have revealed that somatosensory processing relies on a class of implicit body representations showing large distortions of size and shape. The relation between these representations and the conscious body image remains unclear. Dissociations have been reported in the clinical literature on eating disorders between different body image measures, with larger and more consistent distortions found with depictive measures, in which participants compare their body to a visual depict...
Implicit body representations and the conscious body image
Matthew R. Longo; Haggard, P.
2012-01-01
Recent studies have revealed that somatosensory processing relies on a class of implicit body representations showing large distortions of size and shape. The relation between these representations and the conscious body image remains unclear. Dissociations have been reported in the clinical literature on eating disorders between different body image measures, with larger and more consistent distortions found with depictive measures, in which participants compare their body to a visual depict...
Maxwell Chern Simons Theory in a Geometric Representation
Leal, L C
2001-01-01
We quantize the Maxwell Chern Simons theory in a geometric representation that generalizes the Abelian Loop Representation of Maxwell theory. We find that in the physical sector, the model can be seen as the theory of a massles scalar field with a topological interaction that enforces the wave functional to be multivalued. This feature allows to relate the Maxwell Chern Simons theory with the quantum mechanics of particles interacting through a Chern Simons field
The Problem of Representation and Experience in Quantum Mechanics
Ronde, Christian De
2014-03-01
In this paper we discuss the problem of representation and experience in quantum mechanics. We analyze the importance of metaphysics in physical thought and its relation to empiricism and analytic philosophy. We argue against both instrumentalism and scientific realism and claim that both perspectives tend to bypass the problem of representation and justify a "common sense" type experience. Finally, we present our expressionist conception of physics.
Multiple representations and mechanisms for visuomotor adaptation in young children.
Tahej, Pierre-Karim; Ferrel-Chapus, Carole; Olivier, Isabelle; Ginhac, Dominique; Rolland, Jean-Pierre
2012-12-01
In this study, we utilized transformed spatial mappings to perturb visuomotor integration in 5-yr-old children and adults. The participants were asked to perform pointing movements under five different conditions of visuomotor rotation (from 0° to 180°), which were designed to reveal explicit vs. implicit representations as well as the mechanisms underlying the visual-motor mapping. Several tests allowed us to separately evaluate sensorimotor (i.e., the dynamic dimension of movement) and cognitive (i.e., the explicit representations of target position and the strategies used by the participants) representations of visuo-proprioceptive distortion. Our results indicate that children do not establish representations in the same manner as adults and that children exhibit multiple visuomotor representations. Sensorimotor representations were relatively precise, presumably due to the recovery of proprioceptive information and efferent copy. Furthermore, a bidirectional mechanism was used to re-map visual and motor spaces. In contrast, cognitive representations were supplied with visual information and followed a unidirectional visual-motor mapping. Therefore, it appears that sensorimotor mechanisms develop before the use of explicit strategies during development, and young children showed impaired visuomotor adaptation when confronted with large distortions.
Fidelity of the representation of value in decision-making.
Bays, Paul M; Dowding, Ben A
2017-03-01
The ability to make optimal decisions depends on evaluating the expected rewards associated with different potential actions. This process is critically dependent on the fidelity with which reward value information can be maintained in the nervous system. Here we directly probe the fidelity of value representation following a standard reinforcement learning task. The results demonstrate a previously-unrecognized bias in the representation of value: extreme reward values, both low and high, are stored significantly more accurately and precisely than intermediate rewards. The symmetry between low and high rewards pertained despite substantially higher frequency of exposure to high rewards, resulting from preferential exploitation of more rewarding options. The observed variation in fidelity of value representation retrospectively predicted performance on the reinforcement learning task, demonstrating that the bias in representation has an impact on decision-making. A second experiment in which one or other extreme-valued option was omitted from the learning sequence showed that representational fidelity is primarily determined by the relative position of an encoded value on the scale of rewards experienced during learning. Both variability and guessing decreased with the reduction in the number of options, consistent with allocation of a limited representational resource. These findings have implications for existing models of reward-based learning, which typically assume defectless representation of reward value.
The Examining Mathematical Word Problems Solving Ability under Efficient Representation Aspect
Maryam Sajadi
2013-02-01
Full Text Available Word problem solving is complex process for students. Efficient instruction of word problem solving needed to efficient strategies. One of these strategies is using representation. Some students apply key words or numbers only but when they face complex word problems then they cannot apply the keywords. Therefore teachers have to teach efficient strategy such as representation. In this research is tried whether using efficient representation can lead to efficient solution. Through cluster sampling method, forty one students are selected at girly elementary school. Through math exam, their solutions are studied. Through Spearman test, results indicate that there is significant relation between efficient representation and efficient word problem solving ability. At second grade, students have used of representation, have gotten to high means and inverse, students have not used of representation, have not gotten to high means. Therefore there is significant and direct relation between efficient representation and efficient word problem solving ability.
32 CFR 724.215 - Military representation.
2010-07-01
... 32 National Defense 5 2010-07-01 2010-07-01 false Military representation. 724.215 Section 724.215... BOARD Authority/Policy for Departmental Discharge Review § 724.215 Military representation. Military... consult legal counsel before undertaking such representation. Such representation may be prohibited by 18...
Tippett, Christine Diane
Scientific knowledge is constructed and communicated through a range of forms in addition to verbal language. Maps, graphs, charts, diagrams, formulae, models, and drawings are just some of the ways in which science concepts can be represented. Representational competence---an aspect of visual literacy that focuses on the ability to interpret, transform, and produce visual representations---is a key component of science literacy and an essential part of science reading and writing. To date, however, most research has examined learning from representations rather than learning with representations. This dissertation consisted of three distinct projects that were related by a common focus on learning from visual representations as an important aspect of scientific literacy. The first project was the development of an exploratory framework that is proposed for use in investigations of students constructing and interpreting multimedia texts. The exploratory framework, which integrates cognition, metacognition, semiotics, and systemic functional linguistics, could eventually result in a model that might be used to guide classroom practice, leading to improved visual literacy, better comprehension of science concepts, and enhanced science literacy because it emphasizes distinct aspects of learning with representations that can be addressed though explicit instruction. The second project was a metasynthesis of the research that was previously conducted as part of the Explicit Literacy Instruction Embedded in Middle School Science project (Pacific CRYSTAL, http://www.educ.uvic.ca/pacificcrystal). Five overarching themes emerged from this case-to-case synthesis: the engaging and effective nature of multimedia genres, opportunities for differentiated instruction using multimodal strategies, opportunities for assessment, an emphasis on visual representations, and the robustness of some multimodal literacy strategies across content areas. The third project was a mixed
Collaborative Representation based Classification for Face Recognition
Zhang, Lei; Feng, Xiangchu; Ma, Yi; Zhang, David
2012-01-01
By coding a query sample as a sparse linear combination of all training samples and then classifying it by evaluating which class leads to the minimal coding residual, sparse representation based classification (SRC) leads to interesting results for robust face recognition. It is widely believed that the l1- norm sparsity constraint on coding coefficients plays a key role in the success of SRC, while its use of all training samples to collaboratively represent the query sample is rather ignored. In this paper we discuss how SRC works, and show that the collaborative representation mechanism used in SRC is much more crucial to its success of face classification. The SRC is a special case of collaborative representation based classification (CRC), which has various instantiations by applying different norms to the coding residual and coding coefficient. More specifically, the l1 or l2 norm characterization of coding residual is related to the robustness of CRC to outlier facial pixels, while the l1 or l2 norm c...
An new representation for interconnection network structures
刘丽华; 陈建二; 陈松乔; 贾维嘉
2002-01-01
An important theoretic interest is to study the relations between different interconnection networks, and to compare the capability and performance of the network structures. The most popular way to do the investigation is network emulation. Based on the classical voltage graph theory, the authors develop a new representation scheme for interconnection network structures. The new approach is a combination of algebraic methods and combinatorial methods. The results demonstrate that the voltage graph theory is a powerful tool for representing well-known interconnection networks and in implementing optimal network emulation algorithms, and in particular, show that all popular interconnection networks have very simple and intuitive representations under the new scheme. The new representation scheme also offers powerful tools for the study of network routings and emulations. For example, we present very simple constructions for optimal network emulations from the cube-connected cycles networks to the butterfly networks, and from the butterfly networks to the hypercube networks. Compared with the most popular way of network emulation, this new scheme is intuitive and easy to realize, and easy to apply to other network structures.
Representations Of The Super-virasoro Algebra fock Representations
Polychronidis, V J
1999-01-01
In this dissertation the complete classification of the Super- Virasoro modules M (h, c) of the Neveu-Schwarz and Ramond algebras is constructed. A family of representations F p, po of the Neveu- Schwarz and Ramond algebras, which generalize the Fock representations of the Virasoro algebra, is constructed. The Felder's construction of Fock space resolutions for the Virasoro minimal models is generalized in the Super-Virasoro minimal models case. In particular, a two-sided resolution of the irreducible Super-Verma module L( h, c) of the Neveu- Schwarz algebra is provided. --- 8 --- AN
Continued fraction representation of temporal multiscaling in turbulence
Daems, D; Lvov, V S; Procaccia, I; Daems, David; Grossmann, Siegfried; L'vov, Victor S.; Procaccia, Itamar
1999-01-01
It was shown recently that the anomalous scaling of simultaneous correlation functions in turbulence is intimately related to the breaking of temporal scale invariance, which is equivalent to the appearance of infinitely many times scales in the time dependence of time-correlation functions. In this paper we derive a continued fraction representation of turbulent time correlation functions which is exact and in which the multiplicity of time scales is explicit. We demonstrate that this form yields precisely the same scaling laws for time derivatives and time integrals as the "multi-fractal" representation that was used before. Truncating the continued fraction representation yields the "best" estimates of time correlation functions if the given information is limited to the scaling exponents of the simultaneous correlation functions up to a certain, finite order. It is worth noting that the derivation of a continued fraction representation obtained here for an operator which is not Hermitian or anti-Hermitian...
Crystal Structure Representations for Machine Learning Models of Formation Energies
Faber, Felix; von Lilienfeld, O Anatole; Armiento, Rickard
2015-01-01
We introduce and evaluate a set of feature vector representations of crystal structures for machine learning (ML) models of formation energies of solids. ML models of atomization energies of organic molecules have been successful using a Coulomb matrix representation of the molecule. We consider three ways to generalize such representations to periodic systems: (i) a matrix where each element is related to the Ewald sum of the electrostatic interaction between two different atoms in the unit cell repeated over the lattice; (ii) an extended Coulomb-like matrix that takes into account a number of neighboring unit cells; and (iii) an Ansatz that mimics the periodicity and the basic features of the elements in the Ewald sum matrix by using a sine function of the crystal coordinates of the atoms. The representations are compared for a Laplacian kernel with Manhattan norm, trained to reproduce formation energies using a data set of 3938 crystal structures obtained from the Materials Project. For training sets consi...
Boson representations, non-standard quantum algebras and contractions
Ballesteros, A; Negro, J; Ballesteros, Angel; Herranz, Francisco J.; Negro, Javier
1996-01-01
A Gelfan'd-Dyson mapping is used to generate a one-boson realization for the non-standard quantum deformation of $sl(2,\\R)$ which directly provides its infinite and finite dimensional irreducible representations. Tensor product decompositions are worked out for some examples. Relations between contraction methods and boson realizations are also explored in several contexts. So, a class of two-boson representations for the non-standard deformation of $sl(2,\\R)$ is introduced and contracted to the non-standard quantum (1+1) Poincaré representations. Likewise, a quantum extended Hopf $sl(2,\\R)$ algebra is constructed and the Jordanian $q$-oscillator algebra representations are obtained from it by means of another contraction procedure.
Gendered Representations of Fandom
Gürsimsek, Ödül A
2016-01-01
discursive perspective that demonstrates that gender dynamics plays a role in interpreting the material related to fiction and the points of view of the other fan groups. The audience discourse that is shaped and negotiated by men and women who deliberate the so-called gendered interests in online mixed-gender...
Representation and participation
Knudsen, Herman Lyhne
2004-01-01
The introductory chapter adresses the necessity to struggle for voice in a Europe where there is a contest between unilateral and bipartite industrial relations regimes at the workplace and as well as in society and its institutions and discourses more generally....
The DTW-based representation space for seismic pattern classification
Orozco-Alzate, Mauricio; Castro-Cabrera, Paola Alexandra; Bicego, Manuele; Londoño-Bonilla, John Makario
2015-12-01
Distinguishing among the different seismic volcanic patterns is still one of the most important and labor-intensive tasks for volcano monitoring. This task could be lightened and made free from subjective bias by using automatic classification techniques. In this context, a core but often overlooked issue is the choice of an appropriate representation of the data to be classified. Recently, it has been suggested that using a relative representation (i.e. proximities, namely dissimilarities on pairs of objects) instead of an absolute one (i.e. features, namely measurements on single objects) is advantageous to exploit the relational information contained in the dissimilarities to derive highly discriminant vector spaces, where any classifier can be used. According to that motivation, this paper investigates the suitability of a dynamic time warping (DTW) dissimilarity-based vector representation for the classification of seismic patterns. Results show the usefulness of such a representation in the seismic pattern classification scenario, including analyses of potential benefits from recent advances in the dissimilarity-based paradigm such as the proper selection of representation sets and the combination of different dissimilarity representations that might be available for the same data.
Representation of grasp postures and anticipatory motor planning in children.
Stöckel, Tino; Hughes, Charmayne M L; Schack, Thomas
2012-11-01
In this study, we investigated anticipatory motor planning and the development of cognitive representation of grasp postures in children aged 7, 8, and 9 years. Overall, 9-year-old children were more likely to plan their movements to end in comfortable postures, and have distinct representational structures of certain grasp postures, compared to the 7- and 8-year old children. Additionally, the sensitivity toward comfortable end-states (end-state comfort) was related to the mental representation of certain grasp postures. Children with grasp comfort related and functionally well-structured representations were more likely to have satisfied end-state comfort in both the simple and the advanced planning condition. In contrast, end-state comfort satisfaction for the advanced planning condition was much lower for children whose cognitive representations were not structured by grasp comfort. The results of the present study support the notion that cognitive action representation plays an important role in the planning and control of grasp postures.
Neural representations of the sense of self.
Klemm, William R
2011-01-01
The brain constructs representations of what is sensed and thought about in the form of nerve impulses that propagate in circuits and network assemblies (Circuit Impulse Patterns, CIPs). CIP representations of which humans are consciously aware occur in the context of a sense of self. Thus, research on mechanisms of consciousness might benefit from a focus on how a conscious sense of self is represented in brain. Like all senses, the sense of self must be contained in patterns of nerve impulses. Unlike the traditional senses that are registered by impulse flow in relatively simple, pauci-synaptic projection pathways, the sense of self is a system- level phenomenon that may be generated by impulse patterns in widely distributed complex and interacting circuits. The problem for researchers then is to identify the CIPs that are unique to conscious experience. Also likely to be of great relevance to constructing the representation of self are the coherence shifts in activity timing relations among the circuits. Consider that an embodied sense of self is generated and contained as unique combinatorial temporal patterns across multiple neurons in each circuit that contributes to constructing the sense of self. As with other kinds of CIPs, those representing the sense of self can be learned from experience, stored in memory, modified by subsequent experiences, and expressed in the form of decisions, choices, and commands. These CIPs are proposed here to be the actual physical basis for conscious thought and the sense of self. When active in wakefulness or dream states, the CIP representations of self act as an agent of the brain, metaphorically as an avatar. Because the selfhood CIP patterns may only have to represent the self and not directly represent the inner and outer worlds of embodied brain, the self representation should have more degrees of freedom than subconscious mind and may therefore have some capacity for a free-will mind of its own. S everal lines of
Executive control influences linguistic representations.
Lev-Ari, Shiri; Keysar, Boaz
2014-02-01
Although it is known that words acquire their meanings partly from the contexts in which they are used, we proposed that the way in which words are processed can also influence their representation. We further propose that individual differences in the way that words are processed can consequently lead to individual differences in the way that they are represented. Specifically, we showed that executive control influences linguistic representations by influencing the coactivation of competing and reinforcing terms. Consequently, people with poorer executive control perceive the meanings of homonymous terms as being more similar to one another, and those of polysemous terms as being less similar to one another, than do people with better executive control. We also showed that bilinguals with poorer executive control experience greater cross-linguistic interference than do bilinguals with better executive control. These results have implications for theories of linguistic representation and language organization.
Concepts, ontologies, and knowledge representation
Jakus, Grega; Omerovic, Sanida; Tomažic, Sašo
2013-01-01
Recording knowledge in a common framework that would make it possible to seamlessly share global knowledge remains an important challenge for researchers. This brief examines several ideas about the representation of knowledge addressing this challenge. A widespread general agreement is followed that states uniform knowledge representation should be achievable by using ontologies populated with concepts. A separate chapter is dedicated to each of the three introduced topics, following a uniform outline: definition, organization, and use. This brief is intended for those who want to get to know
A unified data representation theory for network visualization, ordering and coarse-graining
Kovács, István A.; Mizsei, Réka; Csermely, Péter
2015-09-01
Representation of large data sets became a key question of many scientific disciplines in the last decade. Several approaches for network visualization, data ordering and coarse-graining accomplished this goal. However, there was no underlying theoretical framework linking these problems. Here we show an elegant, information theoretic data representation approach as a unified solution of network visualization, data ordering and coarse-graining. The optimal representation is the hardest to distinguish from the original data matrix, measured by the relative entropy. The representation of network nodes as probability distributions provides an efficient visualization method and, in one dimension, an ordering of network nodes and edges. Coarse-grained representations of the input network enable both efficient data compression and hierarchical visualization to achieve high quality representations of larger data sets. Our unified data representation theory will help the analysis of extensive data sets, by revealing the large-scale structure of complex networks in a comprehensible form.
A unified data representation theory for network visualization, ordering and coarse-graining.
Kovács, István A; Mizsei, Réka; Csermely, Péter
2015-09-08
Representation of large data sets became a key question of many scientific disciplines in the last decade. Several approaches for network visualization, data ordering and coarse-graining accomplished this goal. However, there was no underlying theoretical framework linking these problems. Here we show an elegant, information theoretic data representation approach as a unified solution of network visualization, data ordering and coarse-graining. The optimal representation is the hardest to distinguish from the original data matrix, measured by the relative entropy. The representation of network nodes as probability distributions provides an efficient visualization method and, in one dimension, an ordering of network nodes and edges. Coarse-grained representations of the input network enable both efficient data compression and hierarchical visualization to achieve high quality representations of larger data sets. Our unified data representation theory will help the analysis of extensive data sets, by revealing the large-scale structure of complex networks in a comprehensible form.
A unified data representation theory for network visualization, ordering and coarse-graining
Kovács, István A; Csermely, Peter
2014-01-01
Representation of large data sets became a key question of many scientific disciplines in the last decade. Several approaches for network visualization, data ordering and coarse-graining accomplished this goal. However, there was no underlying theoretical framework linking these problems. Here we show an elegant, information theoretic data representation approach as a unified solution of network visualization, data ordering and coarse-graining. The optimal representation is the hardest to distinguish from the original data matrix, measured by the relative entropy. The representation of network nodes as probability distributions provides an efficient visualization method and, in one dimension, an ordering of network nodes and edges. Coarse-grained representations of the input network enable both efficient data compression and hierarchical visualization to achieve high quality representations of larger data sets. Our unified data representation theory will help the analysis of huge data sets in science, by reve...
Graham, Daniel J.; Friedenberg, Jay D.; Rockmore, Daniel N.
2009-02-01
An emerging body of research suggests that artists consistently seek modes of representation that are efficiently processed by the human visual system, and that these shared properties could leave statistical signatures. In earlier work, we showed evidence that perceived similarity of representational art could be predicted using intensity statistics to which the early visual system is attuned, though semantic content was also found to be an important factor. Here we report two studies that examine the visual perception of similarity. We test a collection of non-representational art, which we argue possesses useful statistical and semantic properties, in terms of the relationship between image statistics and basic perceptual responses. We find two simple statistics-both expressed as single values-that predict nearly a third of the overall variance in similarity judgments of abstract art. An efficient visual system could make a quick and reasonable guess as to the relationship of a given image to others (i.e., its context) by extracting these basic statistics early in the visual stream, and this may hold for natural scenes as well as art. But a major component of many types of art is representational content. In a second study, we present findings related to efficient representation of natural scene luminances in landscapes by a well-known painter. We show empirically that elements of contemporary approaches to high-dynamic range tone-mapping-which are themselves deeply rooted in an understanding of early visual system coding-are present in the way Vincent Van Gogh transforms scene luminances into painting luminances. We argue that global tone mapping functions are a useful descriptor of an artist's perceptual goals with respect to global illumination and we present evidence that mapping the scene to a painting with different implied lighting properties produces a less efficient mapping. Together, these studies suggest that statistical regularities in art can shed
Court representation in Russia before 1917 (historical aspect
Konstantin V. Ilyashenko
2015-12-01
Full Text Available Objective basing on the research and analysis of the legislation historical legal sources and other materials to study the process of formation and development of the institution of legal representation in Russia before 1917. Methods the theoretical basis of research is the works of Russian scientists on various aspects of formation development and functioning of the institution of legal representation in Russia from ancient times till 1917. The methodological basis of the research is general scientific methods historical formallogical system and general logical methods analysis synthesis induction and deduction synthesis analogy abstraction. Historicallegal formallegal logicallegal comparative legal methods were applied in the study. The author used the retrospective approach to the study of the issues of legal representation in Russia. Results basing on analysis of normative legal acts regulating relations in the sphere of judicial representation and various doctrinal sources the author has examined the process of the formation and development of the legal representation institution in Russia before 1917 raised the question of providing legal assistance in prerevolutionary Russia. An analogy is drawn between the prerevolutionary legal regulation of the legal representation institution and the modern legislation regulating this legal institution. The conclusion is made about the inadequacy of prerevolutionary legislation regulating relations in the sphere of judicial representation as well as the modern legal regulation of relations in this sphere. It is established that the judicial reform of 1864 improved regulation in this sphere but still did not solve all the problems in this area. The relevance of the study is due to the topicality and the constitutional importance of legal representation for the entire Russian society the need to examine the origins of this legal phenomenon as well as the fact that the institution of legal representation
Rotation-independent representations for haptic movements
Shioiri, Satoshi; Yamazaki, Takanori; Matsumiya, Kazumichi; Kuriki, Ichiro
2013-01-01
The existence of a common mechanism for visual and haptic representations has been reported in object perception. In contrast, representations of movements might be more specific to modalities. Referring to the vertical axis is natural for visual representations whereas a fixed reference axis might be inappropriate for haptic movements and thus also inappropriate for its representations in the brain. The present study found that visual and haptic movement representations are processed independently. A psychophysical experiment examining mental rotation revealed the well-known effect of rotation angle for visual representations whereas no such effect was found for haptic representations. We also found no interference between processes for visual and haptic movements in an experiment where different stimuli were presented simultaneously through visual and haptic modalities. These results strongly suggest that (1) there are separate representations of visual and haptic movements, and (2) the haptic process has a rotation-independent representation. PMID:24005481
Representations p-adiques et equations differentielles
Berger, Laurent
2001-01-01
In this paper, we associate to every $p$-adic representation $V$ a $p$-adic differential equation $\\mathbf(D)^(\\dagger)_(\\mathrm(rig))(V)$, that is to say a module with a connection over the Robba ring. We do this via the theory of Fontaine's $(\\varphi,\\Gamma_K)$-modules. This construction enables us to relate the theory of $(\\varphi,\\Gamma_K)$-modules to $p$-adic Hodge theory. We explain how to construct $\\mathbf(D)_(\\mathrm(cris))(V)$ and $\\mathbf(D)_(\\mathrm(st))(V)$ from $\\mathbf(D)^(\\dag...
On Generalized Weil Representations over Involutive Rings
Gutiérrez, Luis; Soto-Andrade, Jorge
2010-01-01
We construct via generators and relations, generalized Weil representations for analogues of classical $SL(2,k), k$ a field, over involutive base rings $(A, \\ast).$ This family of groups covers different kinds of groups, classical and non classical. We give some examples that include symplectic groups as well as non classical groups like $SL_\\ast(2,A_m), $ where $A_m$ is the finite modular analogue of the algebra of real m-jets in one dimension with its canonical involutive symmetry.
Two qubits in the Dirac representation
Rajagopal, A. K.; Rendell, R. W.
2001-08-01
The Dirac-matrix representation of a general two-qubit system is shown to exhibit quite interesting features. The relativistic symmetries of time reversal T, charge conjugation C, parity P, and their products are reinterpreted here by examining their action on the Bell states. It is shown that only C does not mix the Bell states whereas all others do. The various logic gates of quantum information theory are also expressed in terms of the Dirac matrices. For example, the NOT gate is related to the product of T and P. A two-qubit density matrix is found to be entangled if it is invariant under C.
Three representations of the Ising model
Kruis, Joost; Maris, Gunter
2016-01-01
Statistical models that analyse (pairwise) relations between variables encompass assumptions about the underlying mechanism that generated the associations in the observed data. In the present paper we demonstrate that three Ising model representations exist that, although each proposes a distinct theoretical explanation for the observed associations, are mathematically equivalent. This equivalence allows the researcher to interpret the results of one model in three different ways. We illustrate the ramifications of this by discussing concepts that are conceived as problematic in their traditional explanation, yet when interpreted in the context of another explanation make immediate sense. PMID:27698356
Quantum mechanics using Fradkin's representation
Shajesh, K V; Milton, Kimball A.
2005-01-01
Fradkin's representation is a general method of attacking problems in quantum field theory, having as its basis the functional approach of Schwinger. As a pedagogical illustration of that method, we explicitly formulate it for quantum mechanics (field theory in one dimension) and apply it to the solution of Schrodinger's equation for the quantum harmonic oscillator.
Adaptive representations for reinforcement learning
Whiteson, S.
2010-01-01
This book presents new algorithms for reinforcement learning, a form of machine learning in which an autonomous agent seeks a control policy for a sequential decision task. Since current methods typically rely on manually designed solution representations, agents that automatically adapt their own r
Acquired Equivalence Changes Stimulus Representations
Meeter, M.; Shohamy, D.; Myers, C. E.
2009-01-01
Acquired equivalence is a paradigm in which generalization is increased between two superficially dissimilar stimuli (or antecedents) that have previously been associated with similar outcomes (or consequents). Several possible mechanisms have been proposed, including changes in stimulus representations, either in the form of added associations or…
Octonionic matrix representation and electromagnetism
Chanyal, B. C. [Kumaun University, S. S. J. Campus, Almora (India)
2014-12-15
Keeping in mind the important role of octonion algebra, we have obtained the electromagnetic field equations of dyons with an octonionic 8 x 8 matrix representation. In this paper, we consider the eight - dimensional octonionic space as a combination of two (external and internal) four-dimensional spaces for the existence of magnetic monopoles (dyons) in a higher-dimensional formalism. As such, we describe the octonion wave equations in terms of eight components from the 8 x 8 matrix representation. The octonion forms of the generalized potential, fields and current source of dyons in terms of 8 x 8 matrix are discussed in a consistent manner. Thus, we have obtained the generalized Dirac-Maxwell equations of dyons from an 8x8 matrix representation of the octonion wave equations in a compact and consistent manner. The generalized Dirac-Maxwell equations are fully symmetric Maxwell equations and allow for the possibility of magnetic charges and currents, analogous to electric charges and currents. Accordingly, we have obtained the octonionic Dirac wave equations in an external field from the matrix representation of the octonion-valued potentials of dyons.
Minimal Surfaces for Hitchin Representations
Li, Qiongling; Dai, Song
2016-01-01
Given a reductive representation $\\rho: \\pi_1(S)\\rightarrow G$, there exists a $\\rho$-equivariant harmonic map $f$ from the universal cover of a fixed Riemann surface $\\Sigma$ to the symmetric space $G/K$ associated to $G$. If the Hopf differential of $f$ vanishes, the harmonic map is then minimal...
Reusable Lexical Representations for Idioms
Odijk, J.E.J.M.
2004-01-01
In this paper I introduce (1) a technically simple and highly theory-independent way for lexically representing flexible idiomatic expressions, and (2) a procedure to incorporate these lexical representations in a wide variety of NLP systems. The method is based on Structural EQuivalence Classes
Empirical studies on word representations
Suster, Simon
2016-01-01
One of the most fundamental tasks in natural language processing is representing words with mathematical objects (such as vectors). The word representations, which are most often estimated from data, allow capturing the meaning of words. They enable comparing words according to their semantic simila
Reusable Lexical Representations for Idioms
Odijk, J.E.J.M.
2004-01-01
In this paper I introduce (1) a technically simple and highly theory-independent way for lexically representing flexible idiomatic expressions, and (2) a procedure to incorporate these lexical representations in a wide variety of NLP systems. The method is based on Structural EQuivalence Classes for
Correct Representation of Conformational Equilibria.
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…
Spectral representation of Gaussian semimartingales
Basse-O'Connor, Andreas
2009-01-01
The aim of the present paper is to characterize the spectral representation of Gaussian semimartingales. That is, we provide necessary and sufficient conditions on the kernel K for X t =∫ K t (s) dN s to be a semimartingale. Here, N denotes an independently scattered Gaussian random measure...
Representational Momentum in Older Adults
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…
Measurable representation of biconjugate integrands
Ottavio Caligaris
1986-11-01
Full Text Available We find here a representation of convex regularization of a non convex proper function and of a non convex proper normal integrand by means of a suitable multifunction which reveals to be very useful in existence theorems for non convex problems of calculus of variations.
Mental Representations of Social Status
Chiao, Joan Y.; Bordeaux, Andrew R.; Ambady, Nalni
2004-01-01
How do people think about social status? We investigated the nature of social status and number representations using a semantic distance latency test. In Study 1, 21 college students compared words connoting different social status as well as numbers, which served as a control task. Participants were faster at comparing occupations and numbers…
Consistent representations of and conversions between 3D rotations
Rowenhorst, D.; Rollett, A. D.; Rohrer, G. S.; Groeber, M.; Jackson, M.; Konijnenberg, P. J.; De Graef, M.
2015-12-01
In materials science the orientation of a crystal lattice is described by means of a rotation relative to an external reference frame. A number of rotation representations are in use, including Euler angles, rotation matrices, unit quaternions, Rodrigues-Frank vectors and homochoric vectors. Each representation has distinct advantages and disadvantages with respect to the ease of use for calculations and data visualization. It is therefore convenient to be able to easily convert from one representation to another. However, historically, each representation has been implemented using a set of often tacit conventions; separate research groups would implement different sets of conventions, thereby making the comparison of methods and results difficult and confusing. This tutorial article aims to resolve these ambiguities and provide a consistent set of conventions and conversions between common rotational representations, complete with worked examples and a discussion of the trade-offs necessary to resolve all ambiguities. Additionally, an open source Fortran-90 library of conversion routines for the different representations is made available to the community.
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
Knudsen, Søren; Carpendale, Sheelagh
2016-01-01
In this paper, we explore the potential of using visual representations to support people in managing, organizing, and understanding relations between multiple visualization views. Multiple views can help people understand different facets of data and data processing, and are a crucial part of data...... analysis particularly when it is done collaboratively. Both the growing use of multiple views and the increasing display sizes have amplified the need to explore how to better help people to understand the relations between many views. To improve our understanding of how to visualize view relations, we...... invited visualization and interaction designers to critique and sketch representations of view relations. The participants provided design critiques, and sketched their own relation representations. Our findings expand the range and palette of ways of visually linking visualization views and suggest new...
Gil, Vicent; Reybrouck, Mark; Tejada, Jesús; Verschaffel, Lieven
2015-01-01
This intervention-based study focuses on the relation between music and its graphic representation from a meta-representational point of view. It aims to determine whether middle school students show an increase in meta-representational competence (MRC) after an educational intervention. Three classes of 11 to 14-year-old students participated in…
Chen, Qi; Mirman, Daniel
2012-01-01
One of the core principles of how the mind works is the graded, parallel activation of multiple related or similar representations. Parallel activation of multiple representations has been particularly important in the development of theories and models of language processing, where coactivated representations ("neighbors") have been shown to…
22 CFR 1422.17 - Election procedure; request for authorized representation election observers.
2010-04-01
... representation election observers. 1422.17 Section 1422.17 Foreign Relations FOREIGN SERVICE LABOR RELATIONS...; request for authorized representation election observers. This section governs all elections conducted... among the employees in the unit. (f) Any party may be represented at the polling place(s) by...
29 CFR 101.17 - Initiation of representation cases and petitions for clarification and amendment.
2010-07-01
... 29 Labor 2 2010-07-01 2010-07-01 false Initiation of representation cases and petitions for clarification and amendment. 101.17 Section 101.17 Labor Regulations Relating to Labor NATIONAL LABOR RELATIONS... Initiation of representation cases and petitions for clarification and amendment. The investigation of the...
Maria José P. M. de Almeida
2013-06-01
Full Text Available Este estudo foi realizado com o objetivo de investigar representações de pesquisadores da área de ensino de Física sobre a possível interferência da pesquisa da área de ensino de Ciências na maneira como se formam professores no Brasil. Para tal, foram analisadas as respostas a uma questão formulada em entrevistas a treze pesquisadores do ensino da Física, indicados por seus pares por meio de correio eletrônico encaminhado a pesquisadores do ensino de Ciências, incluindo as subáreas de Biologia, Física, Geociências e Química. A análise de discurso desenvolvida na França por Michel Pêcheux, a partir de subsídios obtidos principalmente em publicações de Eni Orlandi no Brasil, foi o apoio teórico que sustentou o estudo. As representações que os discursos selecionados permitem inferir evidenciam pequena influência. Entretanto, foram enunciados fatores de grande abrangência, incluindo desde aqueles internos à própria área, quanto fatores associados a políticas públicas. Também se observou uma diversidade de posições entre os pesquisadores entrevistados. No conjunto, os fatores abordados pelos entrevistados constituem um amplo quadro configurativo de representações que pode ser elemento de reflexão para outros pesquisadores. Acreditamos que essas representações têm potencial de contribuição para efetivas interferências na forma de realização de políticas públicas, sem a necessidade do uso de prescrições e cada vez menos com recomendações vazias.This study was conducted with the objective of investigating representations of researchers from the area of the teaching of Physics about the possible influence of the research in the area of Science teaching upon the way in which teachers are educated in Brazil. For that, an analysis was made of the answers to a question formulated in interviews made with 13 researchers from the field of the teaching of Physics, which were indicated by their peers through an
Mental Representation in The Thought of Sidney Blatt: Developmental Processes.
Auerbach, John S; Diamond, Diana
2017-06-01
Mental representation was a central construct in Sidney Blatt's contributions to psychology and psychoanalysis. This brief review demonstrates that Blatt's understanding of representation was always informed by basic psychoanalytic concepts like the centrality of early caregiver-infant relationships and of unconscious mental processes. Although Blatt's earlier writings were informed by psychoanalytic ego psychology and Piagetian cognitive developmental psychology, they focused nonetheless on how an individual uses bodily and relational experiences to construct an object world; they also consistently presented object representations as having significant unconscious dimensions. From the mid-1980s onward, Blatt's contributions, in dialogue with his many students, moved in an even more experiential/relational direction and manifested the influence of attachment theory, parent-infant interaction research, and intersubjectivity theory. They also incorporated contemporary cognitive psychology, with its emphasis on implicit or procedural, rather than explicit, dimensions as a means of accounting for aspects of object representations that are not in conscious awareness. Throughout his career, however, Blatt regarded mental representation as the construct that mediates between the child's earliest bodily and relational experiences and the mature adult's symbolic, most emotionally profound capacities.
[Mental health and women's work: images and representations of nurses].
Fernandes, Josicelia Dumêt; Ferreira, Silvia Lúcia; Albergaria, Aurenice Karine; da Conceição, Flávia Matos
2002-01-01
This investigation advances on the perspective of the construction of knowledge on the relation between mental health and nursing work. It is a descriptive study based on a qualitative approach and on the Social Representations Theory as well as studies on Psychopathology and Work Psychodynamics. The analysis indicated that nurses representations on the relation between mental health and nursing work are influenced by the individual and collective-organizational levels, showing these professionals as a product and producers of their personal history and of the mental health regarding the work environment, understanding them as a manifestation of the social totality.
Changes in the representation of women and minorities in biomedical careers.
Myers, Samuel L; Fealing, Kaye Husbands
2012-11-01
To examine how efforts and policies to increase diversity affect the relative representation of women and of minority groups within medicine and related science fields. The authors of this report used data from the Current Population Survey March Supplement (a product of the U.S. Census Bureau and the Bureau of Labor Statistics that tracks race, ethnicity, and employment) to compute the representation ratios of persons employed in biology, chemistry, and medicine from 1968 to 2009 (inclusive). They derived the representation ratios by computing the ratio of the conditional probability that a member of a given group is employed in a specific skilled science field to the overall probability of employment in that field. Their analysis tested for differences in representation ratios among racial, gender, and ethnic groups and across time among those employed as biologists, chemists, and medical doctors. Representation ratios rose for white females, whose percentage increase in medicine was larger than for any other racial/ethnic group. The representation ratios fell for Hispanics in biology, chemistry, and medicine. The representation ratio rose for African Americans, whose highest percentage increase occurred in biology. Asian Americans, who had the highest representation ratios in all three disciplines, saw a decline in their relative representation in medicine. The authors have demonstrated that all groups do not benefit equally from diversity initiatives and that competition across related fields can confound efforts to increase diversity in medicine.
The extended loop representation of quantum gravity
Di Bartolo, C; Griego, J R
1995-01-01
A new representation of Quantum Gravity is developed. This formulation is based on an extension of the group of loops. The enlarged group, that we call the Extended Loop Group, behaves locally as an infinite dimensional Lie group. Quantum Gravity can be realized on the state space of extended loop dependent wavefunctions. The extended representation generalizes the loop representation and contains this representation as a particular case. The resulting diffeomorphism and hamiltonian constraints take a very simple form and allow to apply functional methods and simplify the loop calculus. In particular we show that the constraints are linear in the momenta. The nondegenerate solutions known in the loop representation are also solutions of the constraints in the new representation. The practical calculation advantages allows to find a new solution to the Wheeler-DeWitt equation. Moreover, the extended representation puts in a precise framework some of the regularization problems of the loop representation. We sh...
FILMIC REPRESENTATION IN POSTCOLONIAL DISCOURSE: A ...
implicated in the public debate about representation. Representations come in .... A mapping of the dominant discourse, a reading and expressing of its .... This relationship, not only boosted Europe and developed. America, also, Africa was ...
Representation learning for cross-modality classification
G. van Tulder (Gijs); M. de Bruijne (Marleen)
2017-01-01
textabstractDifferences in scanning parameters or modalities can complicate image analysis based on supervised classification. This paper presents two representation learning approaches, based on autoencoders, that address this problem by learning representations that are similar across domains. Bot
The communicative constitution of representation and exclusion
Wessel, van M.G.J.
2014-01-01
In the light of current debate on representation, specifically engaging with literature showing how representation is communicatively constituted, this paper empirically shows how exclusion also can be seen as communicatively constituted. The interpretive approach toward communication employed in th
Multiple Interactive Representations for Fractions Learning
Feenstra, Laurens; Aleven, Vincent; Rummel, Nikol; Taatgen, Niels; Aleven,; Kay, J; Mostow, J
2010-01-01
Multiple External Representations (MERs) have been used successfully in instructional activities, including fractions However, students often have difficulties making the connections between the MERs spontaneously We argue that interactive fraction representations may help students in discovering re
The communicative constitution of representation and exclusion
Wessel, van M.G.J.
2014-01-01
In the light of current debate on representation, specifically engaging with literature showing how representation is communicatively constituted, this paper empirically shows how exclusion also can be seen as communicatively constituted. The interpretive approach toward communication employed in th
Some Representations of Unified Voigt Functions
M. KAMARUJJAMA; Dinesh SINGH
2005-01-01
The authors derive a set of unified representations of the Voigt functions in terms of familiar special functions of Mathematical Physics. Some deductions from these representations are also considered.
A geometric representation for the Proca model
Camacaro, J; Leal, L C; Camacaro, Jaime; Gaitan, Rolando; Leal, Lorenzo
1996-01-01
The Proca model is quantized in an open-path dependent representation that generalizes the Loop Representation of gauge theories. The starting point is a gauge invariant Lagrangian that reduces to the Proca Lagrangian when certain gauge is selected.
Kernel representations for behaviors over finite rings
Kuijper, M.; Pinto, R.; Polderman, J.W.; Yamamoto, Y.
2006-01-01
In this paper we consider dynamical systems finite rings. The rings that we study are the integers modulo a power of a given prime. We study the theory of representations for such systems, in particular kernel representations.
Hologram representation of design data in an expert system knowledge base
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.
Transfinite tree quivers and their representations
Enochs, E; Özdemir, S
2012-01-01
The idea of "vertex at the infinity" naturally appears when studying indecomposable injective representations of tree quivers. In this paper we formalize this behavior and find the structure of all the indecomposable injective representations of a tree quiver of size an arbitrary cardinal $\\kappa$. As a consequence the structure of injective representations of noetherian $\\kappa$-trees is completely determined. In the second part we will consider the problem whether arbitrary trees are source injective representation quivers or not.
The dynamics of social representations in a situation of immigration
Aicha Belarbi
2004-10-01
Full Text Available For the author, globalisation, defined as the internationalisation of exchanges, involves bearing in mind the migration issue in great national and international strategic concerns. Discourses on migration are closely linked with social representations in migratory events. This article constitutes an attempt to focus on the dynamics of social relations in a multicultural situation generated by migration, the objective of which lies in deconstructing the socialrepresentations of the immigrant. With the aim of establishing a theoretical framework for capturing the dynamics of immigrants’ representations and making the instability and fragility of these relations explicit, it presents a brief historical compendium of immigration, before situating the stages of the construction of the social representation, differentiating identity and otherness.
Renormalization of Polyakov loops in fundamental and higher representations
Kaczmarek, O; Hübner, K
2007-01-01
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 $T \\gsim T_c$ 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 bindin...
Paired structures in knowledge representation
Montero, J.; Bustince, H.; Franco de los Ríos, Camilo;
2016-01-01
In this position paper we propose a consistent and unifying view to all those basic knowledge representation models that are based on the existence of two somehow opposite fuzzy concepts. A number of these basic models can be found in fuzzy logic and multi-valued logic literature. Here it is clai......In this position paper we propose a consistent and unifying view to all those basic knowledge representation models that are based on the existence of two somehow opposite fuzzy concepts. A number of these basic models can be found in fuzzy logic and multi-valued logic literature. Here...... of paired structures, generated from two paired concepts together with their associated neutrality, all of them to be modeled as fuzzy sets. In this way, paired structures can be viewed as a standard basic model from which different models arise. This unifying view should therefore allow a deeper analysis...
Representation theory of finite monoids
Steinberg, Benjamin
2016-01-01
This first text on the subject provides a comprehensive introduction to the representation theory of finite monoids. Carefully worked examples and exercises provide the bells and whistles for graduate accessibility, bringing a broad range of advanced readers to the forefront of research in the area. Highlights of the text include applications to probability theory, symbolic dynamics, and automata theory. Comfort with module theory, a familiarity with ordinary group representation theory, and the basics of Wedderburn theory, are prerequisites for advanced graduate level study. Researchers in algebra, algebraic combinatorics, automata theory, and probability theory, will find this text enriching with its thorough presentation of applications of the theory to these fields. Prior knowledge of semigroup theory is not expected for the diverse readership that may benefit from this exposition. The approach taken in this book is highly module-theoretic and follows the modern flavor of the theory of finite dimensional ...
Berry phase in Heisenberg representation
Andreev, V. A.; Klimov, Andrei B.; Lerner, Peter B.
1994-01-01
We define the Berry phase for the Heisenberg operators. This definition is motivated by the calculation of the phase shifts by different techniques. These techniques are: the solution of the Heisenberg equations of motion, the solution of the Schrodinger equation in coherent-state representation, and the direct computation of the evolution operator. Our definition of the Berry phase in the Heisenberg representation is consistent with the underlying supersymmetry of the model in the following sense. The structural blocks of the Hamiltonians of supersymmetrical quantum mechanics ('superpairs') are connected by transformations which conserve the similarity in structure of the energy levels of superpairs. These transformations include transformation of phase of the creation-annihilation operators, which are generated by adiabatic cyclic evolution of the parameters of the system.
Representations of mad cow disease.
Washer, Peter
2006-01-01
This paper examines the reporting of the story of Bovine Spongiform Encephalopathy (BSE) and its human derivative variant Creutzfeld-Jacob Disease (vCJD) in the British newspapers. Three 'snapshots' of newspaper coverage are sampled and analysed between the period 1986 and 1996 focusing on how representations of the disease evolved over the 10-year period. Social representations theory is used to elucidate how this new disease threat was conceptualised in the newspaper reporting and how it was explained to the UK public. This paper examines who or what was said to be at risk from the new disease, and whether some individuals or groups held to blame for the diseases' putative origins, the appearance of vCJD in human beings, and its spread.
Time representations in social science.
Schulz, Yvan
2012-12-01
Time has long been a major topic of study in social science, as in other sciences or in philosophy. Social scientists have tended to focus on collective representations of time, and on the ways in which these representations shape our everyday experiences. This contribution addresses work from such disciplines as anthropology, sociology and history. It focuses on several of the main theories that have preoccupied specialists in social science, such as the alleged "acceleration" of life and overgrowth of the present in contemporary Western societies, or the distinction between so-called linear and circular conceptions of time. The presentation of these theories is accompanied by some of the critiques they have provoked, in order to enable the reader to form her or his own opinion of them.
Time representations in social science
Schulz, Yvan
2012-01-01
Time has long been a major topic of study in social science, as in other sciences or in philosophy. Social scientists have tended to focus on collective representations of time, and on the ways in which these representations shape our everyday experiences. This contribution addresses work from such disciplines as anthropology, sociology and history. It focuses on several of the main theories that have preoccupied specialists in social science, such as the alleged “acceleration” of life and overgrowth of the present in contemporary Western societies, or the distinction between so-called linear and circular conceptions of time. The presentation of these theories is accompanied by some of the critiques they have provoked, in order to enable the reader to form her or his own opinion of them. PMID:23393420
Sparse representation of astronomical images.
Rebollo-Neira, Laura; Bowley, James
2013-04-01
Sparse representation of astronomical images is discussed. It is shown that a significant gain in sparsity is achieved when particular mixed dictionaries are used for approximating these types of images with greedy selection strategies. Experiments are conducted to confirm (i) the effectiveness at producing sparse representations and (ii) competitiveness, with respect to the time required to process large images. The latter is a consequence of the suitability of the proposed dictionaries for approximating images in partitions of small blocks. This feature makes it possible to apply the effective greedy selection technique called orthogonal matching pursuit, up to some block size. For blocks exceeding that size, a refinement of the original matching pursuit approach is considered. The resulting method is termed "self-projected matching pursuit," because it is shown to be effective for implementing, via matching pursuit itself, the optional backprojection intermediate steps in that approach.
Bridging the Gap: Possible Roles and Contributions of Representational Momentum
Timothy L. Hubbard
2006-01-01
Full Text Available Memory for the position of a moving target is often displaced in the direction of anticipated motion, and this has been referred to as representational momentum. Such displacement might aid spatial localization by bridging the gap between perception and action, and might reflect a second-order isomorphism between subjective consequences of environmentally invariant physical principles and the functional architecture of mental representation that can be modulated by an observers expectations (e.g., that a moving target will change its heading or by the presence of nontarget stimuli (e.g., landmarks. Representational momentum and related types of displacement reflect properties of the world and properties of mental representation, and so a consideration of representational momentum and related types of displacement contribute an important component of contemporary psychophysics, and also broaden the reach of psychophysics to include numerous topics not usually considered within psychophysics (e.g., naive physics, boundary extension, flash-lag effect, aesthetics, mental imagery.
Phases of stable representations of quivers
Engenhorst, Magnus
2015-01-01
We consider stable representations of non-Dynkin quivers with respect to a central charge. On one condition the existence of a stable representation with self-extensions implies the existence of infinitely many stables without self-extensions. In this case the phases of the stable representations approach one or two limit points. In particular, the phases are not dense in two arcs.
On Nambu-Lie 3-algebra representations
Sochichiu, Corneliu
2008-01-01
We propose a recipe to construct matrix representations of Nambu--Lie 3-algebras in terms of irreducible representations of underlying Lie algebra. The case of Euclidean four-dimensional 3-algebra is considered in details. We find that representations of this 3-algebra are not possible in terms of only Hermitian matrices in spite of its Euclidean nature.
37 CFR 350.2 - Representation.
2010-07-01
... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Representation. 350.2 Section... ROYALTY JUDGES RULES AND PROCEDURES GENERAL ADMINISTRATIVE PROVISIONS § 350.2 Representation. Individual... representation that the attorney is a member of the bar, in one or more states, in good standing. ...
24 CFR 180.305 - Representation.
2010-04-01
... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Representation. 180.305 Section 180... Representation. (a) HUD is represented by the General Counsel. (b) Any party may appear on his/her/its own behalf... State. The attorney's representation that he/she is in good standing before any of these courts is...
2010-01-01
... 4 Accounts 1 2010-01-01 2010-01-01 false Representation. 28.25 Section 28.25 Accounts GOVERNMENT... Parties, Practitioners and Witnesses § 28.25 Representation. (a) All parties to a petition may be..., in the petition or responsive pleading. Any subsequent changes in representation shall also be in...
75 FR 32273 - Representation Election Procedure
2010-06-08
... 29 CFR Parts 1202 and 1206 RIN 3140-ZA00 Representation Election Procedure AGENCY: National Mediation... delaying the effective date of its rule regarding representation election procedures from June 10, 2010 to... Representation Election Procedure Rule have been made. The NMB will notify participants if there are any further...
33 CFR 20.301 - Representation.
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Representation. 20.301 Section 20... Motions § 20.301 Representation. (a) A party may appear— (1) Without counsel; (2) With an attorney; or (3... United States. A personal representation of membership is sufficient proof, unless the ALJ orders more...
29 CFR 4003.6 - Representation.
2010-07-01
... 29 Labor 9 2010-07-01 2010-07-01 false Representation. 4003.6 Section 4003.6 Labor Regulations... OF AGENCY DECISIONS General Provisions § 4003.6 Representation. A person may file any document or... of attorney, signed by the person making the designation, which authorizes the representation and...
7 CFR 917.15 - Representation area.
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Representation area. 917.15 Section 917.15 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... CALIFORNIA Order Regulating Handling Definitions § 917.15 Representation area. Representation area means any...
76 FR 37291 - Representation Case Procedures
2011-06-27
... BOARD 29 CFR Parts 101, 102, 103 RIN 3142-AAO8 Representation Case Procedures AGENCY: National Labor... amendments to the Board's rules governing representation case procedures, published at 76 FR 15307 (June 22, 2011) and make other proposals for improving representation case procedures. DATES: The meeting will be...
27 CFR 71.30 - Personal representation.
2010-04-01
... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Personal representation. 71.30 Section 71.30 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... General Representation at Hearings § 71.30 Personal representation. Any individual or member of a...
46 CFR 401.615 - Representation.
2010-10-01
... 46 Shipping 8 2010-10-01 2010-10-01 false Representation. 401.615 Section 401.615 Shipping COAST... Representation. (a) The U.S. Registered Pilot, designated “respondent” in a suspension or revocation hearing or... a representation that under the provisions of this subpart and applicable law he is authorized and...
48 CFR 2009.570-4 - Representation.
2010-10-01
... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Representation. 2009.570-4... ACQUISITION PLANNING CONTRACTOR QUALIFICATIONS Organizational Conflicts of Interest 2009.570-4 Representation... interest representation provision at 2052.209-71 must be included in solicitations and contracts resulting...
29 CFR 18.34 - Representation.
2010-07-01
... 29 Labor 1 2010-07-01 2010-07-01 true Representation. 18.34 Section 18.34 Labor Office of the... ADMINISTRATIVE LAW JUDGES General § 18.34 Representation. (a) Appearances. Any party shall have the right to... own representation that he or she is in good standing before any of such courts shall be sufficient...
2010-07-01
... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Representation. 4.9 Section 4.9 Judicial... OF 1974 § 4.9 Representation. The applicant may be represented before the Commission by any person... constitute a representation to the Commission that under the provisions of this part and applicable law he is...
12 CFR 704.14 - Representation.
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Representation. 704.14 Section 704.14 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS CORPORATE CREDIT UNIONS § 704.14 Representation. (a) Board representation. The board will be determined as stipulated in its...
45 CFR 1613.4 - Authorized representation.
2010-10-01
... 45 Public Welfare 4 2010-10-01 2010-10-01 false Authorized representation. 1613.4 Section 1613.4... ON LEGAL ASSISTANCE WITH RESPECT TO CRIMINAL PROCEEDINGS § 1613.4 Authorized representation. Legal... professional responsibility requires representation in a criminal proceeding arising out of a transaction with...
Imitation and the Dialectic of Representation.
Zelazo, Philip David; Lourenco, Stella Felix
2003-01-01
Describes a theory of the understanding and use of representations, drawing heavily on Paul Ricoeur's and James Mark Baldwin's theories. Presents this theory as construing representation as intrinsically mimetic, characterizing the development of representational understanding as internalization, and emphasizing the importance of self-reflection…
Representation of critical natural capital in China.
Lü, Yihe; Zhang, Liwei; Zeng, Yuan; Fu, Bojie; Whitham, Charlotte; Liu, Shuguang; Wu, Bingfang
2017-08-01
Traditional means of assessing representativeness of conservation value in protected areas depend on measures of structural biodiversity. The effectiveness of priority conservation areas at representing critical natural capital (CNC) (i.e., an essential and renewable subset of natural capital) remains largely unknown. We analyzed the representativeness of CNC-conservation priority areas in national nature reserves (i.e., nature reserves under jurisdiction of the central government with large spatial distribution across the provinces) in China with a new biophysical-based composite indicator approach. With this approach, we integrated the net primary production of vegetation, topography, soil, and climate variables to map and rank terrestrial ecosystems capacities to generate CNC. National nature reserves accounted for 6.7% of CNC-conservation priority areas across China. Considerable gaps (35.2%) existed between overall (or potential) CNC representativeness nationally and CNC representation in national reserves, and there was significant spatial heterogeneity of representativeness in CNC-conservation priority areas at the regional and provincial levels. For example, the best and worst representations were, respectively, 13.0% and 1.6% regionally and 28.9% and 0.0% provincially. Policy in China is transitioning toward the goal of an ecologically sustainable civilization. We identified CNC-conservation priority areas and conservation gaps and thus contribute to the policy goals of optimization of the national nature reserve network and the demarcation of areas critical to improving the representativeness and conservation of highly functioning areas of natural capital. Moreover, our method for assessing representation of CNC can be easily adapted to other large-scale networks of conservation areas because few data are needed, and our model is relatively simple. © 2017 Society for Conservation Biology.
Penile representations in ancient Greek art.
Rempelakos, L; Tsiamis, C; Poulakou-Rebelakou, E
2013-12-01
The presentation of the cult of phallus in ancient Greece and the artistic appearance of the phenomenon on vase figures and statues, as indicative of the significant role of the male genitalia in all fertility ceremonies. The examination of a great number of penile representations from the ancient Greek pottery and sculpture and the review of the ancient theater plays (satiric dramas and comedies ). Phallus in artistic representation is connected either with gods of fertility, such as the goat-footed and horned Pan or the ugly dwarf Priapus or the semi-animal nailed figures Satyrs, devotees of the god Dionysus accompanying him in all ritual orgiastic celebrations. Phallus also symbolizes good luck, health and sexuality: people bear or wear artificial phalli exactly like the actors as part of their costume or carry huge penises during the festive ritual processions. On the contrary, the Olympic gods or the ordinary mortals are not imaged ithyphallic; the ideal type of male beauty epitomized in classical sculpture, normally depicts genitals of average or less than average size. It is noteworthy that many of these images belong to athletes during or immediately after hard exercise with the penis shrunk. The normal size genitalia may have been simply a convention to distinguish normal people from the gods of sexuality and fertility, protectors of the reproductive process of Nature. The representation of the over-sized and erected genitalia on vase figures or statues of ancient Greek art is related to fertility gods such as Priapus, Pan and Satyrs and there is strong evidence that imagination and legend were replacing the scientific achievements in the field of erectile function for many centuries.
Temporal Representation in Semantic Graphs
Levandoski, J J; Abdulla, G M
2007-08-07
A wide range of knowledge discovery and analysis applications, ranging from business to biological, make use of semantic graphs when modeling relationships and concepts. Most of the semantic graphs used in these applications are assumed to be static pieces of information, meaning temporal evolution of concepts and relationships are not taken into account. Guided by the need for more advanced semantic graph queries involving temporal concepts, this paper surveys the existing work involving temporal representations in semantic graphs.
Receptive fields and visual representations
Watson, Andrew B.
1989-01-01
Efficient representation of images for human use requires an understanding of how the brain processes and represents visual information. Spatial imagery is represented in the brain in the receptive fields of visual neurons. Models of these neurons lead to models of image fidelity, and to digital implementations of these neural codes. This approach will be illustrated by two example codes. The advantages and difficulties of this approach will be discussed.
Computing Visible-Surface Representations,
1985-03-01
Terzopoulos N00014-75-C-0643 9. PERFORMING ORGANIZATION NAME AMC ADDRESS 10. PROGRAM ELEMENT. PROJECT, TASK Artificial Inteligence Laboratory AREA A...Massachusetts Institute of lechnolog,. Support lbr the laboratory’s Artificial Intelligence research is provided in part by the Advanced Rtccarcl Proj...dynamically maintaining visible surface representations. Whether the intention is to model human vision or to design competent artificial vision systems
SAR Image Complex Pixel Representations
Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2015-03-01
Complex pixel values for Synthetic Aperture Radar (SAR) images of uniform distributed clutter can be represented as either real/imaginary (also known as I/Q) values, or as Magnitude/Phase values. Generally, these component values are integers with limited number of bits. For clutter energy well below full-scale, Magnitude/Phase offers lower quantization noise than I/Q representation. Further improvement can be had with companding of the Magnitude value.
Approximate Representations and Approximate Homomorphisms
Moore, Cristopher
2010-01-01
Approximate algebraic structures play a defining role in arithmetic combinatorics and have found remarkable applications to basic questions in number theory and pseudorandomness. Here we study approximate representations of finite groups: functions f:G -> U_d such that Pr[f(xy) = f(x) f(y)] is large, or more generally Exp_{x,y} ||f(xy) - f(x)f(y)||^2$ is small, where x and y are uniformly random elements of the group G and U_d denotes the unitary group of degree d. We bound these quantities in terms of the ratio d / d_min where d_min is the dimension of the smallest nontrivial representation of G. As an application, we bound the extent to which a function f : G -> H can be an approximate homomorphism where H is another finite group. We show that if H's representations are significantly smaller than G's, no such f can be much more homomorphic than a random function. We interpret these results as showing that if G is quasirandom, that is, if d_min is large, then G cannot be embedded in a small number of dimensi...
Eisenstein series and automorphic representations
Fleig, Philipp; Kleinschmidt, Axel; Persson, Daniel
2015-01-01
We provide an introduction to the theory of Eisenstein series and automorphic forms on real simple Lie groups G, emphasising the role of representation theory. It is useful to take a slightly wider view and define all objects over the (rational) adeles A, thereby also paving the way for connections to number theory, representation theory and the Langlands program. Most of the results we present are already scattered throughout the mathematics literature but our exposition collects them together and is driven by examples. Many interesting aspects of these functions are hidden in their Fourier coefficients with respect to unipotent subgroups and a large part of our focus is to explain and derive general theorems on these Fourier expansions. Specifically, we give complete proofs of Langlands' constant term formula for Eisenstein series on adelic groups G(A) as well as the Casselman--Shalika formula for the p-adic spherical Whittaker vector associated to unramified automorphic representations of G(Q_p). Somewhat ...
Symbol Systems and Pictorial Representations
Diederich, Joachim; Wright, Susan
All problem-solvers are subject to the same ultimate constraints -- limitations on space, time, and materials (Minsky, 1985). He introduces two principles: (1) Economics: Every intelligence must develop symbol-systems for representing objects, causes and goals, and (2) Sparseness: Every evolving intelligence will eventually encounter certain very special ideas -- e.g., about arithmetic, causal reasoning, and economics -- because these particular ideas are very much simpler than other ideas with similar uses. An extra-terrestrial intelligence (ETI) would have developed symbol systems to express these ideas and would have the capacity of multi-modal processing. Vakoch (1998) states that ...``ETI may rely significantly on other sensory modalities (than vision). Particularly useful representations would be ones that may be intelligible through more than one sensory modality. For instance, the information used to create a three-dimensional representation of an object might be intelligible to ETI heavily reliant on either visual or tactile sensory processes.'' The cross-modal representations Vakoch (1998) describes and the symbol systems Minsky (1985) proposes are called ``metaphors'' when combined. Metaphors allow for highly efficient communication. Metaphors are compact, condensed ways of expressing an idea: words, sounds, gestures or images are used in novel ways to refer to something they do not literally denote. Due to the importance of Minsky's ``economics'' principle, it is therefore possible that a message heavily relies on metaphors.
Community representation in hospital decision making: a literature review.
Murray, Zoë
2015-06-01
Advancing quality in health services requires structures and processes that are informed by consumer input. Although this agenda is well recognised, few researchers have focussed on the establishment and maintenance of customer input throughout the structures and processes used to produce high-quality, safe care. We present an analysis of literature outlining the barriers and enablers involved in community representation in hospital governance. The review aimed to explore how community representation in hospital governance is achieved. Studies spanning 1997-2012 were analysed using Donabedian' s model of quality systems as a guide for categories of interest: structure, in relation to administration of quality; process, which is particularly concerned with cooperation and culture; and outcome, considered, in this case, to be the achievement of effective community representation on quality of care. There are limited published studies on community representation in hospital governance in Australia. What can be gleaned from the literature is: 1) quality subcommittees set up to assist Hospital Boards are a key structure for involving community representation in decision making around quality of care, and 2) there are a number of challenges to effectively developing the process of community representation in hospital governance: ambiguity and the potential for escalated indecision; inadequate value and consideration given to it by decision makers resulting in a lack of time and resources needed to support the community engagement strategy (time, facilitation, budgets); poor support and attitude amongst staff; and consumer issues, such as feeling isolated and intimidated by expert opinion. The analysis indicates that: quality subcommittees set up to assist boards are a key structure for involving community representation in decision making around quality of care. There are clearly a number of challenges to effectively developing the process of community representation in
Cláudio Luis da Cunha Gastal
2007-08-01
Full Text Available Este artigo origina-se de uma pesquisa qualitativa que analisou representações sociais relacionadas ao direito à saúde de usuários de dois serviços de saúde mental: um constituído e funcionando com participação de usuários e familiares e outro sem essa participação, visando conhecê-las não apenas vinculadas à consciência do direito à saúde, mas também a fatores associados, como: participação popular, o processo de adoecimento; o atendimento público de saúde, percepção da capacidade de intervenção social, e concepções sobre o Estado. As representações sociais encontradas associadas ao direito à saúde implicam expectativas de que o sistema de saúde e o Estado cumpram funções de acolhimento e amparo. Os usuários do serviço sem participação popular tendem a ser mais conformados e pessimistas. O grupo com participação popular vê o serviço que construiu como possuidor das características negadas pelo sistema oficial e percebe como possível a ação reivindicativa, podendo ser um foco alternativo na formação de novas representações sociais.The present paper originated from a qualitative study that analyzed social representations related to the right to health, expressed by users of two types of mental health services, one with participation by users and families and the other without such participation. The aim was to analyze such representations not only in relation to the awareness of the right to health, but also concerning associated factors, such as: popular participation; illness; public health care; perception of social intervention capacity; and concepts concerning the state. Social representations of the right to health involve expectations that the health system and the state meet their roles of ensuring care and support. Users of the mental health service without user/family participation tended to be more resigned and pessimistic. The group with participation views the service it has built
Brewster, Hilary D
2009-01-01
The theory of relativity has become a cornerstone of modern physics. Over the course of time it has been scrutinized in a multitude of experiments and has always been verified with high accuracy. The correctness of this theory can no longer be called into question. Right after its discovery by Albert Einstein in 1905, special relativity was only gradually accepted because it made numerous predictions contradicting common sense, fervently castigated by Einstein, and also defied experiment for too long a time. It was only with the advent of particle or high energy physics that matter could be ac
Einstein, Albert
2013-01-01
Time magazine's ""Man of the Century"", Albert Einstein is the founder of modern physics and his theory of relativity is the most important scientific idea of the modern era. In this short book, Einstein explains, using the minimum of mathematical terms, the basic ideas and principles of the theory that has shaped the world we live in today. Unsurpassed by any subsequent books on relativity, this remains the most popular and useful exposition of Einstein's immense contribution to human knowledge.With a new foreword by Derek Raine.
Cognition and procedure representational requirements for predictive human performance models
Corker, K.
1992-01-01
Models and modeling environments for human performance are becoming significant contributors to early system design and analysis procedures. Issues of levels of automation, physical environment, informational environment, and manning requirements are being addressed by such man/machine analysis systems. The research reported here investigates the close interaction between models of human cognition and models that described procedural performance. We describe a methodology for the decomposition of aircrew procedures that supports interaction with models of cognition on the basis of procedures observed; that serves to identify cockpit/avionics information sources and crew information requirements; and that provides the structure to support methods for function allocation among crew and aiding systems. Our approach is to develop an object-oriented, modular, executable software representation of the aircrew, the aircraft, and the procedures necessary to satisfy flight-phase goals. We then encode in a time-based language, taxonomies of the conceptual, relational, and procedural constraints among the cockpit avionics and control system and the aircrew. We have designed and implemented a goals/procedures hierarchic representation sufficient to describe procedural flow in the cockpit. We then execute the procedural representation in simulation software and calculate the values of the flight instruments, aircraft state variables and crew resources using the constraints available from the relationship taxonomies. The system provides a flexible, extensible, manipulative and executable representation of aircrew and procedures that is generally applicable to crew/procedure task-analysis. The representation supports developed methods of intent inference, and is extensible to include issues of information requirements and functional allocation. We are attempting to link the procedural representation to models of cognitive functions to establish several intent inference methods
Coxian Representations of Generalized Erlang Distributions
Qi-ming He; Han-qin Zhang
2009-01-01
This paper studies Coxian representations of generalized Erlang distributions. A nonlinear program is derived for computing the parameters of minimal Coxian representations of generalized Erlang distributions.The nonlinear program is also used to characterize the triangular order and the admissible region of generalized Erlang distributions. It is shown that the admissible region associated with a triangular order may not be convex. For generalized Erlang distributions of ME-order 3, a minimal Coxian representation is found explicitly.In addition, an algorithm is developed for computing a special type of ordered Coxian representations - the bivariate Coxian representation - for generalized Erlang distributions.
Adrián Gurza Lavalle
2007-01-01
Full Text Available This article examines the new forms of political representation civil organisations are constructing in their relation with the State, and some of the possible consequences for the quality of democracy. There are no historical or theoretical established models of representation which enable one to explore how civil organisations, in the absence of the elections or formal membership, can construct their political representativeness. For this reason, political representation by civil organisations has received little attention despite its growing importance. Extensive fieldwork in São Paulo, Brazil, reveals that political representation by civil organisations is closely connected to the dynamics of institutions of representative democracy. Furthermore, it reveals that alongside notions of representation that are clearly irreconcilable with democratic standards, a new notion of representation is emerging among civil organisations which is specifically political and compatible with democracy.
Representation Methods in AI. Searching by Graphs
Angel GARRIDO
2012-12-01
Full Text Available The historical origin of the Artificial Intelligence (A I is usually established in the Darmouth Conference, of 1956. But we can find many more arcane origins [1]. Also, we can consider, in more recent times, very great thinkers, as Janos Neumann (then, John von Neumann, arrived in USA, Norbert Wiener, Alan Mathison Turing, or Lofti Zadehfor instance [6, 7]. Frequently A I requires Logic. But its classical version shows too many insufficiencies. So, it was necessary to introduce more sophisticated tools, as fuzzy logic, modal logic, non-monotonic logic and so on [2]. Among the things that A I needs to represent are: categories, objects, properties, relations between objects, situations, states, time, events, causes and effects, knowledge about knowledge, and so on. The problems in A I can be classified in two general types [3, 4]: search problems and representation problems. In this last “mountain”, there exist different ways to reach their summit. So, we have [3]: logics, rules, frames, associative nets, scripts and so on, many times connectedamong them. We attempt, in this paper, a panoramic vision of the scope of application of such Representation Methods in A I. The two more disputable questions of both modern philosophy of mind and A I will be Turing Test and The Chinese Room Argument. To elucidate these very difficult questions, see both final Appendices.
Attention Stabilizes Representations in the Human Hippocampus.
Aly, Mariam; Turk-Browne, Nicholas B
2016-02-01
Attention and memory are intricately linked, but how attention modulates brain areas that subserve memory, such as the hippocampus, is unknown. We hypothesized that attention may stabilize patterns of activity in human hippocampus, resulting in distinct but reliable activity patterns for different attentional states. To test this prediction, we utilized high-resolution functional magnetic resonance imaging and a novel "art gallery" task. On each trial, participants viewed a room containing a painting, and searched a stream of rooms for a painting from the same artist (art state) or a room with the same layout (room state). Bottom-up stimulation was the same in both tasks, enabling the isolation of neural effects related to top-down attention. Multivariate analyses revealed greater pattern similarity in all hippocampal subfields for trials from the same, compared with different, attentional state. This stability was greater for the room than art state, was unrelated to univariate activity, and, in CA2/CA3/DG, was correlated with behavior. Attention therefore induces representational stability in the human hippocampus, resulting in distinct activity patterns for different attentional states. Modulation of hippocampal representational stability highlights the far-reaching influence of attention outside of sensory systems.