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Sample records for receptive field based

  1. Contour detection based on nonclassical receptive field inhibition

    NARCIS (Netherlands)

    Grigorescu, Cosmin; Petkov, Nicolai; Westenberg, Michel A.

    We propose a biologically motivated computational step, called nonclassical receptive field (non-CRF) inhibition, more generally surround inhibition or suppression, to improve contour detection in machine vision. Non-CRF inhibition is exhibited by 80% of the orientation-selective neurons in the

  2. Bayesian population receptive field modelling.

    Science.gov (United States)

    Zeidman, Peter; Silson, Edward Harry; Schwarzkopf, Dietrich Samuel; Baker, Chris Ian; Penny, Will

    2017-09-08

    We introduce a probabilistic (Bayesian) framework and associated software toolbox for mapping population receptive fields (pRFs) based on fMRI data. This generic approach is intended to work with stimuli of any dimension and is demonstrated and validated in the context of 2D retinotopic mapping. The framework enables the experimenter to specify generative (encoding) models of fMRI timeseries, in which experimental stimuli enter a pRF model of neural activity, which in turns drives a nonlinear model of neurovascular coupling and Blood Oxygenation Level Dependent (BOLD) response. The neuronal and haemodynamic parameters are estimated together on a voxel-by-voxel or region-of-interest basis using a Bayesian estimation algorithm (variational Laplace). This offers several novel contributions to receptive field modelling. The variance/covariance of parameters are estimated, enabling receptive fields to be plotted while properly representing uncertainty about pRF size and location. Variability in the haemodynamic response across the brain is accounted for. Furthermore, the framework introduces formal hypothesis testing to pRF analysis, enabling competing models to be evaluated based on their log model evidence (approximated by the variational free energy), which represents the optimal tradeoff between accuracy and complexity. Using simulations and empirical data, we found that parameters typically used to represent pRF size and neuronal scaling are strongly correlated, which is taken into account by the Bayesian methods we describe when making inferences. We used the framework to compare the evidence for six variants of pRF model using 7 T functional MRI data and we found a circular Difference of Gaussians (DoG) model to be the best explanation for our data overall. We hope this framework will prove useful for mapping stimulus spaces with any number of dimensions onto the anatomy of the brain. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Receptive fields selection for binary feature description.

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    Fan, Bin; Kong, Qingqun; Trzcinski, Tomasz; Wang, Zhiheng; Pan, Chunhong; Fua, Pascal

    2014-06-01

    Feature description for local image patch is widely used in computer vision. While the conventional way to design local descriptor is based on expert experience and knowledge, learning-based methods for designing local descriptor become more and more popular because of their good performance and data-driven property. This paper proposes a novel data-driven method for designing binary feature descriptor, which we call receptive fields descriptor (RFD). Technically, RFD is constructed by thresholding responses of a set of receptive fields, which are selected from a large number of candidates according to their distinctiveness and correlations in a greedy way. Using two different kinds of receptive fields (namely rectangular pooling area and Gaussian pooling area) for selection, we obtain two binary descriptors RFDR and RFDG .accordingly. Image matching experiments on the well-known patch data set and Oxford data set demonstrate that RFD significantly outperforms the state-of-the-art binary descriptors, and is comparable with the best float-valued descriptors at a fraction of processing time. Finally, experiments on object recognition tasks confirm that both RFDR and RFDG successfully bridge the performance gap between binary descriptors and their floating-point competitors.

  4. Receptive field inference with localized priors.

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    Mijung Park

    2011-10-01

    Full Text Available The linear receptive field describes a mapping from sensory stimuli to a one-dimensional variable governing a neuron's spike response. However, traditional receptive field estimators such as the spike-triggered average converge slowly and often require large amounts of data. Bayesian methods seek to overcome this problem by biasing estimates towards solutions that are more likely a priori, typically those with small, smooth, or sparse coefficients. Here we introduce a novel Bayesian receptive field estimator designed to incorporate locality, a powerful form of prior information about receptive field structure. The key to our approach is a hierarchical receptive field model that flexibly adapts to localized structure in both spacetime and spatiotemporal frequency, using an inference method known as empirical Bayes. We refer to our method as automatic locality determination (ALD, and show that it can accurately recover various types of smooth, sparse, and localized receptive fields. We apply ALD to neural data from retinal ganglion cells and V1 simple cells, and find it achieves error rates several times lower than standard estimators. Thus, estimates of comparable accuracy can be achieved with substantially less data. Finally, we introduce a computationally efficient Markov Chain Monte Carlo (MCMC algorithm for fully Bayesian inference under the ALD prior, yielding accurate Bayesian confidence intervals for small or noisy datasets.

  5. A computational theory of visual receptive fields.

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    Lindeberg, Tony

    2013-12-01

    A receptive field constitutes a region in the visual field where a visual cell or a visual operator responds to visual stimuli. This paper presents a theory for what types of receptive field profiles can be regarded as natural for an idealized vision system, given a set of structural requirements on the first stages of visual processing that reflect symmetry properties of the surrounding world. These symmetry properties include (i) covariance properties under scale changes, affine image deformations, and Galilean transformations of space-time as occur for real-world image data as well as specific requirements of (ii) temporal causality implying that the future cannot be accessed and (iii) a time-recursive updating mechanism of a limited temporal buffer of the past as is necessary for a genuine real-time system. Fundamental structural requirements are also imposed to ensure (iv) mutual consistency and a proper handling of internal representations at different spatial and temporal scales. It is shown how a set of families of idealized receptive field profiles can be derived by necessity regarding spatial, spatio-chromatic, and spatio-temporal receptive fields in terms of Gaussian kernels, Gaussian derivatives, or closely related operators. Such image filters have been successfully used as a basis for expressing a large number of visual operations in computer vision, regarding feature detection, feature classification, motion estimation, object recognition, spatio-temporal recognition, and shape estimation. Hence, the associated so-called scale-space theory constitutes a both theoretically well-founded and general framework for expressing visual operations. There are very close similarities between receptive field profiles predicted from this scale-space theory and receptive field profiles found by cell recordings in biological vision. Among the family of receptive field profiles derived by necessity from the assumptions, idealized models with very good qualitative

  6. Non-linear Galilean vestibular receptive fields.

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    Bennequin, D; Berthoz, A

    2011-01-01

    We present a set of formulas for the receptive fields of the vestibular neurons that are motivated by Galilean invariance. We show that these formulas explain non-trivial data in neurophysiology, and suggest new hypothesis to be tested in dynamical 3D conditions. Moreover our model offers a way for neuronal computing with 3D displacements, which is reputed to be hard, underlying the vestibular reflexes. This computation is presented in a Bayesian framework. The basis of the model is the necessity of living bodies to work invariantly in space-time, allied to the necessary discreteness of neuronal transmission.

  7. Invariance of visual operations at the level of receptive fields.

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    Tony Lindeberg

    Full Text Available The brain is able to maintain a stable perception although the visual stimuli vary substantially on the retina due to geometric transformations and lighting variations in the environment. This paper presents a theory for achieving basic invariance properties already at the level of receptive fields. Specifically, the presented framework comprises (i local scaling transformations caused by objects of different size and at different distances to the observer, (ii locally linearized image deformations caused by variations in the viewing direction in relation to the object, (iii locally linearized relative motions between the object and the observer and (iv local multiplicative intensity transformations caused by illumination variations. The receptive field model can be derived by necessity from symmetry properties of the environment and leads to predictions about receptive field profiles in good agreement with receptive field profiles measured by cell recordings in mammalian vision. Indeed, the receptive field profiles in the retina, LGN and V1 are close to ideal to what is motivated by the idealized requirements. By complementing receptive field measurements with selection mechanisms over the parameters in the receptive field families, it is shown how true invariance of receptive field responses can be obtained under scaling transformations, affine transformations and Galilean transformations. Thereby, the framework provides a mathematically well-founded and biologically plausible model for how basic invariance properties can be achieved already at the level of receptive fields and support invariant recognition of objects and events under variations in viewpoint, retinal size, object motion and illumination. The theory can explain the different shapes of receptive field profiles found in biological vision, which are tuned to different sizes and orientations in the image domain as well as to different image velocities in space-time, from a

  8. Spectrotemporal dynamics of auditory cortical synaptic receptive field plasticity.

    Science.gov (United States)

    Froemke, Robert C; Martins, Ana Raquel O

    2011-09-01

    The nervous system must dynamically represent sensory information in order for animals to perceive and operate within a complex, changing environment. Receptive field plasticity in the auditory cortex allows cortical networks to organize around salient features of the sensory environment during postnatal development, and then subsequently refine these representations depending on behavioral context later in life. Here we review the major features of auditory cortical receptive field plasticity in young and adult animals, focusing on modifications to frequency tuning of synaptic inputs. Alteration in the patterns of acoustic input, including sensory deprivation and tonal exposure, leads to rapid adjustments of excitatory and inhibitory strengths that collectively determine the suprathreshold tuning curves of cortical neurons. Long-term cortical plasticity also requires co-activation of subcortical neuromodulatory control nuclei such as the cholinergic nucleus basalis, particularly in adults. Regardless of developmental stage, regulation of inhibition seems to be a general mechanism by which changes in sensory experience and neuromodulatory state can remodel cortical receptive fields. We discuss recent findings suggesting that the microdynamics of synaptic receptive field plasticity unfold as a multi-phase set of distinct phenomena, initiated by disrupting the balance between excitation and inhibition, and eventually leading to wide-scale changes to many synapses throughout the cortex. These changes are coordinated to enhance the representations of newly-significant stimuli, possibly for improved signal processing and language learning in humans. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Improved contour detection by non-classical receptive field inhibition

    NARCIS (Netherlands)

    Grigorescu, C; Petkov, N; Westenberg, MA; Bulthoff, HH; Lee, SW; Poggio, TA; Wallraven, C

    2002-01-01

    We propose a biologically motivated computational step, called non-classical receptive field (non-CRF) inhibition, to improve the performance of contour detectors. We introduce a Gabor energy operator augmented with non-CRF inhibition, which we call the bar cell operator. We use natural images with

  10. Speech recognition employing biologically plausible receptive fields

    DEFF Research Database (Denmark)

    Fereczkowski, Michal; Bothe, Hans-Heinrich

    2011-01-01

    The main idea of the project is to build a widely speaker-independent, biologically motivated automatic speech recognition (ASR) system. The two main differences between our approach and current state-of-the-art ASRs are that i) the features used here are based on the responses of neuronlike...... Model-based adaptation procedures. Two databases are used, TI46 for discrete speech a subset of the TIMIT database collected from speakers belonging to the New York dialect region. Each of the selection of 10 sentences is uttered once by each of 35 speakers. The major differences between the two data...... sets initiate the development and comparison of two distinct ASRs within the project, which will be presented in the following. Employing a reduced sampling frequency and bandwidth of the signals, the ASR algorithm reaches and goes beyond recognition results that are known from humans....

  11. Temporal variability of spectro-temporal receptive fields in the anesthetized auditory cortex

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    Arne Freerk Meyer

    2014-12-01

    Full Text Available Temporal variability of neuronal response characteristics during sensory stimulation is a ubiquitous phenomenon that may reflect processes such as stimulus-driven adaptation, top-down modulation or spontaneous fluctuations. It poses a challenge to functional characterization methods such as the receptive field, since these often assume stationarity. We propose a novel method for estimation of sensory neurons' receptive fields that extends the classic static linear receptive field model to the time-varying case. Here, the long-term estimate of the static receptive field serves as the mean of a probabilistic prior distribution from which the short-term temporally localized receptive field may deviate stochastically with time-varying standard deviation. The derived corresponding generalized linear model permits robust characterization of temporal variability in receptive field structure also for highly non-Gaussian stimulus ensembles. We computed and analyzed short-term auditory spectro-temporal receptive field (STRF estimates with characteristic temporal resolution 5 s to 30 s based on model simulations and responses from in total 60 single-unit recordings in anesthetized Mongolian gerbil auditory midbrain and cortex. Stimulation was performed with short (100 ms overlapping frequency-modulated tones. Results demonstrate identification of time-varying STRFs, with obtained predictive model likelihoods exceeding those from baseline static STRF estimation. Quantitative characterization of STRF variability reveals a higher degree thereof in auditory cortex compared to midbrain. Cluster analysis indicates that significant deviations from the long-term static STRF are brief, but reliably estimated. We hypothesize that the observed variability more likely reflects spontaneous or state-dependent internal fluctuations that interact with stimulus-induced processing, rather than experimental or stimulus design.

  12. Binaural processing in the synthesis of auditory spatial receptive fields.

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    Peña, José Luis

    2003-11-01

    The owl's auditory system computes interaural time (ITD) and interaural level (ILD) differences to create a two-dimensional map of auditory space. Space-specific neurons are selective for combinations of ITD and ILD, which define, respectively, the horizontal and vertical dimensions of their receptive fields. ITD curves for postsynaptic potentials indicate that ICx neurons integrate the results of binaural cross correlation in different frequency bands. However, the difference between the main and side peaks is slight. ICx neurons further enhance this difference in the process of converting membrane potentials to impulse rates. Comparison of subthreshold postsynaptic potentials (PSPs) and spike output for the same neurons showed that receptive fields measured in PSPs were much larger than those measured in spikes in both ITD and ILD dimensions. A multiplication of separate postsynaptic potentials tuned to ITD and ILD can account for the combination sensitivity of these neurons to ITD-ILD pairs.

  13. Mechanisms for shaping receptive field in monkey area TE.

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    Obara, Keitaro; O'Hashi, Kazunori; Tanifuji, Manabu

    2017-10-01

    Visual object information is conveyed from V1 to area TE along the ventral visual pathway with increasing receptive field (RF) sizes. The RFs of TE neurons are known to be large, but it is largely unknown how large RFs are shaped along the ventral visual pathway. In this study, we addressed this question in two aspects, static and dynamic mechanisms, by recording neural responses from macaque area TE and V4 to object stimuli presented at various locations in the visual field. As a component related to static mechanisms, we found that in area TE, but not in V4, response latency to objects presented at fovea were different from objects in periphery. As a component of the dynamic mechanisms, we examined effects of spatial attention on the RFs of TE neurons. Spatial attention did not affect response latency but modulated response magnitudes depending on attended location, shifting of the longitudinal axis of RFs toward the attended locations. In standard models of large RF formation, downstream neurons pool information from nearby RFs, and this process is repeated across the visual field and at each step along the ventral visual pathway. The present study revealed that this mechanism is not that simple: 1) different circuit mechanisms for foveal and peripheral visual fields may be situated between V4 and area TE, and 2) spatial attention dynamically changes the shape of RFs.NEW & NOTEWORTHY Receptive fields (RFs) of neurons are progressively increased along the ventral visual pathway so that an RF at the final stage, area TE, covers a large area of the visual field. We explored the mechanism and suggested involvement of parallel circuit mechanisms between V4 and TE for foveal and peripheral parts of visual field. We also found a dynamic component of RF shape formation through attentional modulation of responses in a location-dependent manner. Copyright © 2017 the American Physiological Society.

  14. Sensory noise predicts divisive reshaping of receptive fields

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    Deneve, Sophie; Gutkin, Boris

    2017-01-01

    In order to respond reliably to specific features of their environment, sensory neurons need to integrate multiple incoming noisy signals. Crucially, they also need to compete for the interpretation of those signals with other neurons representing similar features. The form that this competition should take depends critically on the noise corrupting these signals. In this study we show that for the type of noise commonly observed in sensory systems, whose variance scales with the mean signal, sensory neurons should selectively divide their input signals by their predictions, suppressing ambiguous cues while amplifying others. Any change in the stimulus context alters which inputs are suppressed, leading to a deep dynamic reshaping of neural receptive fields going far beyond simple surround suppression. Paradoxically, these highly variable receptive fields go alongside and are in fact required for an invariant representation of external sensory features. In addition to offering a normative account of context-dependent changes in sensory responses, perceptual inference in the presence of signal-dependent noise accounts for ubiquitous features of sensory neurons such as divisive normalization, gain control and contrast dependent temporal dynamics. PMID:28622330

  15. Sensory noise predicts divisive reshaping of receptive fields.

    Directory of Open Access Journals (Sweden)

    Matthew Chalk

    2017-06-01

    Full Text Available In order to respond reliably to specific features of their environment, sensory neurons need to integrate multiple incoming noisy signals. Crucially, they also need to compete for the interpretation of those signals with other neurons representing similar features. The form that this competition should take depends critically on the noise corrupting these signals. In this study we show that for the type of noise commonly observed in sensory systems, whose variance scales with the mean signal, sensory neurons should selectively divide their input signals by their predictions, suppressing ambiguous cues while amplifying others. Any change in the stimulus context alters which inputs are suppressed, leading to a deep dynamic reshaping of neural receptive fields going far beyond simple surround suppression. Paradoxically, these highly variable receptive fields go alongside and are in fact required for an invariant representation of external sensory features. In addition to offering a normative account of context-dependent changes in sensory responses, perceptual inference in the presence of signal-dependent noise accounts for ubiquitous features of sensory neurons such as divisive normalization, gain control and contrast dependent temporal dynamics.

  16. Discriminative learning of receptive fields from responses to non-Gaussian stimulus ensembles.

    Directory of Open Access Journals (Sweden)

    Arne F Meyer

    Full Text Available Analysis of sensory neurons' processing characteristics requires simultaneous measurement of presented stimuli and concurrent spike responses. The functional transformation from high-dimensional stimulus space to the binary space of spike and non-spike responses is commonly described with linear-nonlinear models, whose linear filter component describes the neuron's receptive field. From a machine learning perspective, this corresponds to the binary classification problem of discriminating spike-eliciting from non-spike-eliciting stimulus examples. The classification-based receptive field (CbRF estimation method proposed here adapts a linear large-margin classifier to optimally predict experimental stimulus-response data and subsequently interprets learned classifier weights as the neuron's receptive field filter. Computational learning theory provides a theoretical framework for learning from data and guarantees optimality in the sense that the risk of erroneously assigning a spike-eliciting stimulus example to the non-spike class (and vice versa is minimized. Efficacy of the CbRF method is validated with simulations and for auditory spectro-temporal receptive field (STRF estimation from experimental recordings in the auditory midbrain of Mongolian gerbils. Acoustic stimulation is performed with frequency-modulated tone complexes that mimic properties of natural stimuli, specifically non-Gaussian amplitude distribution and higher-order correlations. Results demonstrate that the proposed approach successfully identifies correct underlying STRFs, even in cases where second-order methods based on the spike-triggered average (STA do not. Applied to small data samples, the method is shown to converge on smaller amounts of experimental recordings and with lower estimation variance than the generalized linear model and recent information theoretic methods. Thus, CbRF estimation may prove useful for investigation of neuronal processes in response to

  17. Discriminative learning of receptive fields from responses to non-Gaussian stimulus ensembles.

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    Meyer, Arne F; Diepenbrock, Jan-Philipp; Happel, Max F K; Ohl, Frank W; Anemüller, Jörn

    2014-01-01

    Analysis of sensory neurons' processing characteristics requires simultaneous measurement of presented stimuli and concurrent spike responses. The functional transformation from high-dimensional stimulus space to the binary space of spike and non-spike responses is commonly described with linear-nonlinear models, whose linear filter component describes the neuron's receptive field. From a machine learning perspective, this corresponds to the binary classification problem of discriminating spike-eliciting from non-spike-eliciting stimulus examples. The classification-based receptive field (CbRF) estimation method proposed here adapts a linear large-margin classifier to optimally predict experimental stimulus-response data and subsequently interprets learned classifier weights as the neuron's receptive field filter. Computational learning theory provides a theoretical framework for learning from data and guarantees optimality in the sense that the risk of erroneously assigning a spike-eliciting stimulus example to the non-spike class (and vice versa) is minimized. Efficacy of the CbRF method is validated with simulations and for auditory spectro-temporal receptive field (STRF) estimation from experimental recordings in the auditory midbrain of Mongolian gerbils. Acoustic stimulation is performed with frequency-modulated tone complexes that mimic properties of natural stimuli, specifically non-Gaussian amplitude distribution and higher-order correlations. Results demonstrate that the proposed approach successfully identifies correct underlying STRFs, even in cases where second-order methods based on the spike-triggered average (STA) do not. Applied to small data samples, the method is shown to converge on smaller amounts of experimental recordings and with lower estimation variance than the generalized linear model and recent information theoretic methods. Thus, CbRF estimation may prove useful for investigation of neuronal processes in response to natural stimuli and

  18. From sensors to spikes: evolving receptive fields to enhance sensorimotor information in a robot-arm.

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    Luque, Niceto R; Garrido, Jesús A; Ralli, Jarno; Laredo, Juanlu J; Ros, Eduardo

    2012-08-01

    In biological systems, instead of actual encoders at different joints, proprioception signals are acquired through distributed receptive fields. In robotics, a single and accurate sensor output per link (encoder) is commonly used to track the position and the velocity. Interfacing bio-inspired control systems with spiking neural networks emulating the cerebellum with conventional robots is not a straight forward task. Therefore, it is necessary to adapt this one-dimensional measure (encoder output) into a multidimensional space (inputs for a spiking neural network) to connect, for instance, the spiking cerebellar architecture; i.e. a translation from an analog space into a distributed population coding in terms of spikes. This paper analyzes how evolved receptive fields (optimized towards information transmission) can efficiently generate a sensorimotor representation that facilitates its discrimination from other "sensorimotor states". This can be seen as an abstraction of the Cuneate Nucleus (CN) functionality in a robot-arm scenario. We model the CN as a spiking neuron population coding in time according to the response of mechanoreceptors during a multi-joint movement in a robot joint space. An encoding scheme that takes into account the relative spiking time of the signals propagating from peripheral nerve fibers to second-order somatosensory neurons is proposed. Due to the enormous number of possible encodings, we have applied an evolutionary algorithm to evolve the sensory receptive field representation from random to optimized encoding. Following the nature-inspired analogy, evolved configurations have shown to outperform simple hand-tuned configurations and other homogenized configurations based on the solution provided by the optimization engine (evolutionary algorithm). We have used artificial evolutionary engines as the optimization tool to circumvent nonlinearity responses in receptive fields.

  19. A three-dimensional spatiotemporal receptive field model explains responses of area MT neurons to naturalistic movies.

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    Nishimoto, Shinji; Gallant, Jack L

    2011-10-12

    Area MT has been an important target for studies of motion processing. However, previous neurophysiological studies of MT have used simple stimuli that do not contain many of the motion signals that occur during natural vision. In this study we sought to determine whether views of area MT neurons developed using simple stimuli can account for MT responses under more naturalistic conditions. We recorded responses from macaque area MT neurons during stimulation with naturalistic movies. We then used a quantitative modeling framework to discover which specific mechanisms best predict neuronal responses under these challenging conditions. We find that the simplest model that accurately predicts responses of MT neurons consists of a bank of V1-like filters, each followed by a compressive nonlinearity, a divisive nonlinearity, and linear pooling. Inspection of the fit models shows that the excitatory receptive fields of MT neurons tend to lie on a single plane within the three-dimensional spatiotemporal frequency domain, and suppressive receptive fields lie off this plane. However, most excitatory receptive fields form a partial ring in the plane and avoid low temporal frequencies. This receptive field organization ensures that most MT neurons are tuned for velocity but do not tend to respond to ambiguous static textures that are aligned with the direction of motion. In sum, MT responses to naturalistic movies are largely consistent with predictions based on simple stimuli. However, models fit using naturalistic stimuli reveal several novel properties of MT receptive fields that had not been shown in prior experiments.

  20. Receptive fields of visual neurons: the early years.

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    Spillmann, Lothar

    2014-01-01

    This paper traces the history of the visual receptive field (RF) from Hartline to Hubel and Wiesel. Hartline (1938, 1940) found that an isolated optic nerve fiber in the frog could be excited by light falling on a small circular area of the retina. He called this area the RF, using a term first introduced by Sherrington (1906) in the tactile domain. In 1953 Kuffler discovered the antagonistic center-surround organization of cat RFs, and Barlow, Fitzhugh, and Kuffler (1957) extended this work to stimulus size and state of adaptation. Shortly thereafter, Lettvin and colleagues (1959) in an iconic paper asked "what the frog's eye tells the frog's brain". Meanwhile, Jung and colleagues (1952-1973) searched for the perceptual correlates of neuronal responses, and Jung and Spillmann (1970) proposed the term perceptive field (PF) as a psychophysical correlate of the RF. The Westheimer function (1967) enabled psychophysical measurements of the PF center and surround in human and monkey, which correlated closely with the underlying RF organization. The sixties and seventies were marked by rapid progress in RF research. Hubel and Wiesel (1959-1974), recording from neurons in the visual cortex of the cat and monkey, found elongated RFs selective for the shape, orientation, and position of the stimulus, as well as for movement direction and ocularity. These findings prompted the emergence in visual psychophysics of the concept of feature detectors selective for lines, bars, and edges, and contributed to a model of the RF in terms of difference of Gaussians (DOG) and Fourier channels. The distinction between simple, complex, and hypercomplex neurons followed. Although RF size increases towards the peripheral retina, its cortical representation remains constant due to the reciprocal relationship with the cortical magnification factor (M). This constitutes a uniform yardstick for M-scaled stimuli across the retina. Developmental studies have shown that RF properties are not fixed

  1. A Pixel-Encoder Retinal Ganglion Cell with Spatially Offset Excitatory and Inhibitory Receptive Fields

    OpenAIRE

    Keith P. Johnson; Lei Zhao; Daniel Kerschensteiner

    2018-01-01

    The spike trains of retinal ganglion cells (RGCs) are the only source of visual information to the brain. Here, we genetically identify an RGC type in mice that functions as a pixel encoder and increases firing to light increments (PixON-RGC). PixON-RGCs have medium-sized dendritic arbors and non-canonical center-surround receptive fields. From their receptive field center, PixON-RGCs receive only excitatory input, which encodes contrast and spatial information linearly. From their receptive ...

  2. Comparing different stimulus configurations for population receptive field mapping in human fMRI

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    Ivan eAlvarez

    2015-02-01

    Full Text Available Population receptive field (pRF mapping is a widely used approach to measuring aggregate human visual receptive field properties by recording non-invasive signals using functional MRI. Despite growing interest, no study to date has systematically investigated the effects of different stimulus configurations on pRF estimates from human visual cortex. Here we compared the effects of three different stimulus configurations on a model-based approach to pRF estimation: size-invariant bars and eccentricity-scaled bars defined in Cartesian coordinates and traveling along the cardinal axes, and a novel simultaneous ‘wedge and ring’ stimulus defined in polar coordinates, systematically covering polar and eccentricity axes. We found that the presence or absence of eccentricity scaling had a significant effect on goodness of fit and pRF size estimates. Further, variability in pRF size estimates was directly influenced by stimulus configuration, particularly for higher visual areas including V5/MT+. Finally, we compared eccentricity estimation between phase-encoded and model-based pRF approaches. We observed a tendency for more peripheral eccentricity estimates using phase-encoded methods, independent of stimulus size. We conclude that both eccentricity scaling and polar rather than Cartesian stimulus configuration are important considerations for optimal experimental design in pRF mapping. While all stimulus configurations produce adequate estimates, simultaneous wedge and ring stimulation produced higher fit reliability, with a significant advantage in reduced acquisition time.

  3. Simple-cell-like receptive fields maximize temporal coherence in natural video.

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    Hurri, Jarmo; Hyvärinen, Aapo

    2003-03-01

    Recently, statistical models of natural images have shown the emergence of several properties of the visual cortex. Most models have considered the nongaussian properties of static image patches, leading to sparse coding or independent component analysis. Here we consider the basic time dependencies of image sequences instead of their nongaussianity. We show that simple-cell-type receptive fields emerge when temporal response strength correlation is maximized for natural image sequences. Thus, temporal response strength correlation, which is a nonlinear measure of temporal coherence, provides an alternative to sparseness in modeling simple-cell receptive field properties. Our results also suggest an interpretation of simple cells in terms of invariant coding principles, which have previously been used to explain complex-cell receptive fields.

  4. Systematic variation of population receptive field properties across cortical depth in human visual cortex

    NARCIS (Netherlands)

    Fracasso, Alessio; Petridou, N; Dumoulin, Serge O

    2016-01-01

    Receptive fields (RFs) in visual cortex are organized in antagonistic, center-surround, configurations. RF properties change systematically across eccentricity and between visual field maps. However, it is unknown how center-surround configurations are organized in human visual cortex across lamina.

  5. Reception and learning of electric fields in bees.

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    Greggers, Uwe; Koch, Gesche; Schmidt, Viola; Dürr, Aron; Floriou-Servou, Amalia; Piepenbrock, David; Göpfert, Martin C; Menzel, Randolf

    2013-05-22

    Honeybees, like other insects, accumulate electric charge in flight, and when their body parts are moved or rubbed together. We report that bees emit constant and modulated electric fields when flying, landing, walking and during the waggle dance. The electric fields emitted by dancing bees consist of low- and high-frequency components. Both components induce passive antennal movements in stationary bees according to Coulomb's law. Bees learn both the constant and the modulated electric field components in the context of appetitive proboscis extension response conditioning. Using this paradigm, we identify mechanoreceptors in both joints of the antennae as sensors. Other mechanoreceptors on the bee body are potentially involved but are less sensitive. Using laser vibrometry, we show that the electrically charged flagellum is moved by constant and modulated electric fields and more strongly so if sound and electric fields interact. Recordings from axons of the Johnston organ document its sensitivity to electric field stimuli. Our analyses identify electric fields emanating from the surface charge of bees as stimuli for mechanoreceptors, and as biologically relevant stimuli, which may play a role in social communication.

  6. Receptive field properties of neurons in the primary visual cortex under photopic and scotopic lighting conditions.

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    Duffy, Kevin R; Hubel, David H

    2007-09-01

    Knowledge of the physiology of the primate visual cortex (area V-1) comes mostly from studies done in photopic conditions, in which retinal cones are active and rods play little or no part. Conflicting results have come from research into the effects of dark adaptation on receptive field organization of cells in the retina and the lateral geniculate nucleus. These studies claim either that the effect of the surround disappears with dark adaptation or that it does not. The current study has as its objective a comparison of responses of V-1 cells in awake-alert macaque monkeys under conditions of light and dark adaptation. We reasoned that basic receptive field properties of V-1 cells such as orientation selectivity, direction selectivity, and end-stopping should be preserved in scotopic conditions if the receptive field organization of antecedent cells is maintained in dim light. Our results indicate that dark adaptation does not alter basic V-1 receptive field characteristics such as selectivity for orientation, direction, and bar length.

  7. Limits on perceptual encoding can be predicted from known receptive field properties of human visual cortex.

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    Cohen, Michael A; Rhee, Juliana Y; Alvarez, George A

    2016-01-01

    Human cognition has a limited capacity that is often attributed to the brain having finite cognitive resources, but the nature of these resources is usually not specified. Here, we show evidence that perceptual interference between items can be predicted by known receptive field properties of the visual cortex, suggesting that competition within representational maps is an important source of the capacity limitations of visual processing. Across the visual hierarchy, receptive fields get larger and represent more complex, high-level features. Thus, when presented simultaneously, high-level items (e.g., faces) will often land within the same receptive fields, while low-level items (e.g., color patches) will often not. Using a perceptual task, we found long-range interference between high-level items, but only short-range interference for low-level items, with both types of interference being weaker across hemifields. Finally, we show that long-range interference between items appears to occur primarily during perceptual encoding and not during working memory maintenance. These results are naturally explained by the distribution of receptive fields and establish a link between perceptual capacity limits and the underlying neural architecture. (c) 2015 APA, all rights reserved).

  8. Receptive field properties of rod-driven horizontal cells in the skate retina

    Science.gov (United States)

    1992-01-01

    The large receptive fields of retinal horizontal cells result primarily from extensive intercellular coupling via gap (electrical) junctions; thus, the extent of the receptive field provides an index of the degree to which the cells are electrically coupled. For rod-driven horizontal cells in the dark-adapted skate retina, a space constant of 1.18 +/- 0.15 mm (SD) was obtained from measurements with a moving slit stimulus, and a comparable value (1.43 +/- 0.55 mm) was obtained with variation in spot diameter. These values, and the extensive spread of a fluorescent dye (Lucifer Yellow) from the site of injection to neighboring cells, indicate that the horizontal cells of the all-rod retina of skate are well coupled electrically. Neither the receptive field properties nor the gap-junctional features of skate horizontal cells were influenced by the adaptive state of the retina: (a) the receptive field organization was unaffected by light adaptation, (b) similar dye coupling was seen in both dark- and light-adapted retinae, and (c) no significant differences were found in the gap-junctional particle densities measured in dark- and light-adapted retinas, i.e., 3,184 +/- 286/microns 2 (n = 8) and 3,073 +/- 494/microns 2 (n = 11), respectively. Moreover, the receptive fields of skate horizontal cells were not altered by either dopamine, glycine, GABA, or the GABAA receptor antagonists bicuculline and picrotoxin. We conclude that the rod-driven horizontal cells of the skate retina are tightly coupled to one another, and that the coupling is not affected by photic and pharmacological conditions that are known to modulate intercellular coupling between cone-driven horizontal cells in other species. PMID:1359000

  9. Temporal course of the threshold and size of the receptive field of the Babinski sign.

    Science.gov (United States)

    Estañol, B

    1983-01-01

    The changes of threshold and receptive field of the Babinski reflex, with time, were assessed in ten patients with acute cerebrovascular lesions. It was found that the threshold of the reflex decreased gradually and the size of the cutaneous afferent reflex field enlarged with the passage of time. These findings suggest that there is a gradual release or organisation of the reflex flexor synergy of which the Babinski sign is a modified part. PMID:6606699

  10. Receptive field properties of neurons in the primary visual cortex under photopic and scotopic lighting conditions

    OpenAIRE

    Duffy, Kevin R.; Hubel, David H.

    2007-01-01

    Knowledge of the physiology of the primate visual cortex (area V-1) comes mostly from studies done in photopic conditions, in which retinal cones are active and rods play little or no part. Conflicting results have come from research into the effects of dark adaptation on receptive field organization of cells in the retina and the lateral geniculate nucleus. These studies claim either that the effect of the surround disappears with dark adaptation or that it does not. The current study has as...

  11. Gabor analysis of auditory midbrain receptive fields: spectro-temporal and binaural composition.

    Science.gov (United States)

    Qiu, Anqi; Schreiner, Christoph E; Escabí, Monty A

    2003-07-01

    The spectro-temporal receptive field (STRF) is a model representation of the excitatory and inhibitory integration area of auditory neurons. Recently it has been used to study spectral and temporal aspects of monaural integration in auditory centers. Here we report the properties of monaural STRFs and the relationship between ipsi- and contralateral inputs to neurons of the central nucleus of cat inferior colliculus (ICC) of cats. First, we use an optimal singular-value decomposition method to approximate auditory STRFs as a sum of time-frequency separable Gabor functions. This procedure extracts nine physiologically meaningful parameters. The STRFs of approximately 60% of collicular neurons are well described by a time-frequency separable Gabor STRF model, whereas the remaining neurons exhibited obliquely oriented or multiple excitatory/inhibitory subfields that require a nonseparable Gabor fitting procedure. Parametric analysis reveals distinct spectro-temporal tradeoffs in receptive field size and modulation filtering resolution. Comparisons between an identical model used to study spatio-temporal integration areas of visual neurons further shows that auditory and visual STRFs share numerous structural properties. We then use the Gabor STRF model to compare quantitatively receptive field properties of contra- and ipsilateral inputs to the ICC. We show that most interaural STRF parameters are highly correlated bilaterally. However, the spectral and temporal phases of ipsi- and contralateral STRFs often differ significantly. This suggests that activity originating from each ear share various spectro-temporal response properties such as their temporal delay, bandwidth, and center frequency but have shifted or interleaved patterns of excitation and inhibition. These differences in converging monaural receptive fields expand binaural processing capacity beyond interaural time and intensity aspects and may enable colliculus neurons to detect disparities in the spectro

  12. Delayed maturation of receptive field center/surround mechanisms in V2

    OpenAIRE

    Zhang, Bin; Zheng, Jianghe; Watanabe, Ichiro; Maruko, Ichiro; Bi, Hua; Smith, Earl L.; Chino, Yuzo

    2005-01-01

    Neurons in the adult visual cortex are capable of integrating signals over a large area that surrounds their classic receptive field (RF), and this ability of cortical neurons is thought to be intimately involved in perceptual binding. It is not known, however, at what age these long-range signal interactions emerge. Here, we report that qualitatively adult-like center/surround interactions are already present in the primary visual cortex as early as postnatal day 14 in macaque monkeys. Howev...

  13. Attention directed by expectations enhances receptive fields in cortical area MT.

    Science.gov (United States)

    Ghose, Geoffrey M; Bearl, David W

    2010-02-22

    Expectations, especially those formed on the basis of extensive training, can substantially enhance visual performance. However, it is not clear that the physiological mechanisms underlying this enhancement are identical to those examined by experiments in which attention is directed by explicit instructions rather than strong expectations. To study the changes in visual representations associated with strong expectations, we trained animals to detect a brief motion pulse that was embedded in noise. Because the nature of the pulse and the statistics of its appearance were well known to the animals, they formed strong expectations which determined their behavioral performance. We used white-noise methods to infer the receptive field structure of single neurons in area MT while they were performing this task. Incorporating non-linearities, we compared receptive fields during periods of time when the animals were expecting the motion pulse with periods of time when they were not. We found receptive field changes consistent with an increased reliability in signaling pulse occurrence. Moreover, these changes were not consistent with a simple gain modulation. The results suggest that strong expectations can create very specific changes in the visual representations at a cellular level to enhance performance. Copyright 2009 Elsevier Ltd. All rights reserved.

  14. Neurons in Primate Visual Cortex Alternate between Responses to Multiple Stimuli in Their Receptive Field

    Science.gov (United States)

    Li, Kang; Kozyrev, Vladislav; Kyllingsbæk, Søren; Treue, Stefan; Ditlevsen, Susanne; Bundesen, Claus

    2016-01-01

    A fundamental question concerning representation of the visual world in our brain is how a cortical cell responds when presented with more than a single stimulus. We find supportive evidence that most cells presented with a pair of stimuli respond predominantly to one stimulus at a time, rather than a weighted average response. Traditionally, the firing rate is assumed to be a weighted average of the firing rates to the individual stimuli (response-averaging model) (Bundesen et al., 2005). Here, we also evaluate a probability-mixing model (Bundesen et al., 2005), where neurons temporally multiplex the responses to the individual stimuli. This provides a mechanism by which the representational identity of multiple stimuli in complex visual scenes can be maintained despite the large receptive fields in higher extrastriate visual cortex in primates. We compare the two models through analysis of data from single cells in the middle temporal visual area (MT) of rhesus monkeys when presented with two separate stimuli inside their receptive field with attention directed to one of the two stimuli or outside the receptive field. The spike trains were modeled by stochastic point processes, including memory effects of past spikes and attentional effects, and statistical model selection between the two models was performed by information theoretic measures as well as the predictive accuracy of the models. As an auxiliary measure, we also tested for uni- or multimodality in interspike interval distributions, and performed a correlation analysis of simultaneously recorded pairs of neurons, to evaluate population behavior. PMID:28082892

  15. Visual cortex in aging and Alzheimer's disease: changes in visual field maps and population receptive fields

    Science.gov (United States)

    Brewer, Alyssa A.; Barton, Brian

    2012-01-01

    Although several studies have suggested that cortical alterations underlie such age-related visual deficits as decreased acuity, little is known about what changes actually occur in visual cortex during healthy aging. Two recent studies showed changes in primary visual cortex (V1) during normal aging; however, no studies have characterized the effects of aging on visual cortex beyond V1, important measurements both for understanding the aging process and for comparison to changes in age-related diseases. Similarly, there is almost no information about changes in visual cortex in Alzheimer's disease (AD), the most common form of dementia. Because visual deficits are often reported as one of the first symptoms of AD, measurements of such changes in the visual cortex of AD patients might improve our understanding of how the visual system is affected by neurodegeneration as well as aid early detection, accurate diagnosis and timely treatment of AD. Here we use fMRI to first compare the visual field map (VFM) organization and population receptive fields (pRFs) between young adults and healthy aging subjects for occipital VFMs V1, V2, V3, and hV4. Healthy aging subjects do not show major VFM organizational deficits, but do have reduced surface area and increased pRF sizes in the foveal representations of V1, V2, and hV4 relative to healthy young control subjects. These measurements are consistent with behavioral deficits seen in healthy aging. We then demonstrate the feasibility and first characterization of these measurements in two patients with mild AD, which reveal potential changes in visual cortex as part of the pathophysiology of AD. Our data aid in our understanding of the changes in the visual processing pathways in normal aging and provide the foundation for future research into earlier and more definitive detection of AD. PMID:24570669

  16. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure

    National Research Council Canada - National Science Library

    Miconi, Thomas; VanRullen, Rufin

    2016-01-01

    Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space...

  17. 3-D components of a biological neural network visualized in computer generated imagery. I - Macular receptive field organization

    Science.gov (United States)

    Ross, Muriel D.; Cutler, Lynn; Meyer, Glenn; Lam, Tony; Vaziri, Parshaw

    1990-01-01

    Computer-assisted, 3-dimensional reconstructions of macular receptive fields and of their linkages into a neural network have revealed new information about macular functional organization. Both type I and type II hair cells are included in the receptive fields. The fields are rounded, oblong, or elongated, but gradations between categories are common. Cell polarizations are divergent. Morphologically, each calyx of oblong and elongated fields appears to be an information processing site. Intrinsic modulation of information processing is extensive and varies with the kind of field. Each reconstructed field differs in detail from every other, suggesting that an element of randomness is introduced developmentally and contributes to endorgan adaptability.

  18. MOBIUS-STRIP-LIKE COLUMNAR FUNCTIONAL CONNECTIONS ARE REVEALED IN SOMATO-SENSORY RECEPTIVE FIELD CENTROIDS.

    Directory of Open Access Journals (Sweden)

    James Joseph Wright

    2014-10-01

    Full Text Available Receptive fields of neurons in the forelimb region of areas 3b and 1 of primary somatosensory cortex, in cats and monkeys, were mapped using extracellular recordings obtained sequentially from nearly radial penetrations. Locations of the field centroids indicated the presence of a functional system, in which cortical homotypic representations of the limb surfaces are entwined in three-dimensional Mobius-strip-like patterns of synaptic connections. Boundaries of somatosensory receptive field in nested groups irregularly overlie the centroid order, and are interpreted as arising from the superposition of learned connections upon the embryonic order. Since the theory of embryonic synaptic self-organisation used to model these results was devised and earlier used to explain findings in primary visual cortex, the present findings suggest the theory may be of general application throughout cortex, and may reveal a modular functional synaptic system, which, only in some parts of the cortex, and in some species, is manifest as anatomical ordering into columns.

  19. Radial asymmetries in population receptive field size and cortical magnification factor in early visual cortex.

    Science.gov (United States)

    Silva, Maria Fatima; Brascamp, Jan W; Ferreira, Sónia; Castelo-Branco, Miguel; Dumoulin, Serge O; Harvey, Ben M

    2017-11-14

    Human visual cortex does not represent the whole visual field with the same detail. Changes in receptive field size, population receptive field (pRF) size and cortical magnification factor (CMF) with eccentricity are well established, and associated with changes in visual acuity with eccentricity. Visual acuity also changes across polar angle. However, it remains unclear how RF size, pRF size and CMF change across polar angle. Here, we examine differences in pRF size and CMF across polar angle in V1, V2 and V3 using pRF modeling of human fMRI data. In these visual field maps, we find smaller pRFs and larger CMFs in horizontal (left and right) than vertical (upper and lower) visual field quadrants. Differences increase with eccentricity, approximately in proportion to average pRF size and CMF. Similarly, we find larger CMFs in the lower than upper quadrant, and again differences increase with eccentricity. However, pRF size differences between lower and upper quadrants change direction with eccentricity. Finally, we find slightly smaller pRFs in the left than right quadrants of V2 and V3, though this difference is very small, and we find no differences in V1 and no differences in CMF. Moreover, differences in pRF size and CMF vary gradually with polar angle and are not limited to the meridians or visual field map discontinuities. PRF size and CMF differences do not consistently follow patterns of cortical curvature, despite the link between cortical curvature and polar angle in V1. Thus, the early human visual cortex has a radially asymmetric representation of the visual field. These asymmetries may underlie consistent reports of asymmetries in perceptual abilities. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Looming-sensitive responses and receptive field organization of telencephalic neurons in the pigeon.

    Science.gov (United States)

    Xiao, Qian; Li, Da-Peng; Wang, Shu-Rong

    2006-01-30

    The tectofugal pathway in birds goes from the optic tectum to the telencephalic entopallium via the thalamic nucleus rotundus (nRt). This pathway may be homologous to the colliculo-pulvinar-cortical pathway in mammals. It is known that a population of rotundal neurons in the pigeon can signal impending collision of looming objects with the animal. Here we show by single-unit recording that there exist two groups of looming-sensitive neurons in the entopallium. A tau cell starts firing at a nearly constant time before collision whereas the response onset time of an eta cell is linearly related to the square root of the diameter/velocity ratio of looming objects. These cells are localized in the caudal entopallium. The receptive field (RF) of looming-sensitive cells was mapped on the screen plane but its inhibitory region could not suppress responses to looming objects. It appears that a population of telencephalic cells in pigeons responds to looming objects and their looming responses are not determined by the receptive field organization mapped on the screen plane.

  1. Synaptic Contributions to Receptive Field Structure and Response Properties in the Rodent Lateral Geniculate Nucleus of the Thalamus.

    Science.gov (United States)

    Suresh, Vandana; Çiftçioğlu, Ulaş M; Wang, Xin; Lala, Brittany M; Ding, Kimberly R; Smith, William A; Sommer, Friedrich T; Hirsch, Judith A

    2016-10-26

    Comparative physiological and anatomical studies have greatly advanced our understanding of sensory systems. Many lines of evidence show that the murine lateral geniculate nucleus (LGN) has unique attributes, compared with other species such as cat and monkey. For example, in rodent, thalamic receptive field structure is markedly diverse, and many cells are sensitive to stimulus orientation and direction. To explore shared and different strategies of synaptic integration across species, we made whole-cell recordings in vivo from the murine LGN during the presentation of visual stimuli, analyzed the results with different computational approaches, and compared our findings with those from cat. As for carnivores, murine cells with classical center-surround receptive fields had a "push-pull" structure of excitation and inhibition within a given On or Off subregion. These cells compose the largest single population in the murine LGN (∼40%), indicating that push-pull is key in the form vision pathway across species. For two cell types with overlapping On and Off responses, which recalled either W3 or suppressed-by-contrast ganglion cells in murine retina, inhibition took a different form and was most pronounced for spatially extensive stimuli. Other On-Off cells were selective for stimulus orientation and direction. In these cases, retinal inputs were tuned and, for oriented cells, the second-order subunit of the receptive field predicted the preferred angle. By contrast, suppression was not tuned and appeared to sharpen stimulus selectivity. Together, our results provide new perspectives on the role of excitation and inhibition in retinothalamic processing. We explored the murine lateral geniculate nucleus from a comparative physiological perspective. In cat, most retinal cells have center-surround receptive fields and push-pull excitation and inhibition, including neurons with the smallest (highest acuity) receptive fields. The same is true for thalamic relay cells

  2. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure.

    Science.gov (United States)

    Miconi, Thomas; VanRullen, Rufin

    2016-02-01

    Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space. Several existing models of attention suggest that these effects arise from selective modulation of neural inputs. However, anatomical and physiological observations suggest that attentional modulation targets higher levels of the visual system (such as V4 or MT) rather than input areas (such as V1). Here we propose a simple mechanism that explains how a top-down attentional modulation, falling on higher visual areas, can produce the observed effects of attention on neural responses. Our model requires only the existence of modulatory feedback connections between areas, and short-range lateral inhibition within each area. Feedback connections redistribute the top-down modulation to lower areas, which in turn alters the inputs of other higher-area cells, including those that did not receive the initial modulation. This produces firing rate modulations and receptive field shifts. Simultaneously, short-range lateral inhibition between neighboring cells produce competitive effects that are automatically scaled to receptive field size in any given area. Our model reproduces the observed attentional effects on response rates (response gain, input gain, biased competition automatically scaled to receptive field size) and receptive field structure (shifts and resizing of receptive fields both spatially and in complex feature space), without modifying model parameters. Our model also makes the novel prediction that attentional effects on response curves should shift from response gain to contrast gain as the spatial focus of attention drifts away from the studied cell.

  3. Spatiotemporal receptive field properties of epiretinally recorded spikes and local electroretinograms in cats

    Directory of Open Access Journals (Sweden)

    Wilms Marcus

    2005-08-01

    Full Text Available Abstract Background Receptive fields of retinal neural signals of different origin can be determined from extracellular microelectrode recordings at the inner retinal surface. However, locations and types of neural processes generating the different signal components are difficult to separate and identify. We here report epiretinal receptive fields (RFs from simultaneously recorded spikes and local electroretinograms (LERGs using a semi-chronic multi-electrode in vivo recording technique in cats. Broadband recordings were filtered to yield LERG and multi unit as well as single unit spike signals. RFs were calculated from responses to multifocal pseudo-random spatiotemporal visual stimuli registered at the retinal surface by a 7-electrode array. Results LERGs exhibit spatially unimodal RFs always centered at the location of the electrode tip. Spike-RFs are either congruent with LERG-RFs (N = 26/61 or shifted distally (N = 35/61 but never proximally with respect to the optic disk. LERG-RFs appear at shorter latencies (11.9 ms ± 0.5 ms, N = 18 than those of spikes (18.6 ms ± 0.4 ms, N = 53. Furthermore, OFF-center spike-RFs precede and have shorter response rise times than ON-center spike-RFs. Our results indicate that displaced spike-RFs result from action potentials of ganglion cell axons passing the recording electrode en route to the optic disk while LERG-RFs are related to superimposed postsynaptic potentials of cells near the electrode tip. Conclusion Besides contributing to the understanding of retinal function we demonstrate the caveats that come with recordings from the retinal surface, i.e., the likelihood of recordings from mixed sets of retinal neurons. Implications for the design of an epiretinal visual implant are discussed.

  4. A study on reception electrodes for the vital-sign monitor using near-field intra-body communication enhanced by spread spectrum technique.

    Science.gov (United States)

    Kobayashi, Takumi; Shimatani, Yuichi; Kyoso, Masaki

    2013-01-01

    As a novel vital sign monitor, we have developed wireless ECG monitoring system with Near-field intra-body communication (NF-IBC) technique. However, it was hard to ensure communication reliability because transmission channel is noisy and unstable. In order to solve the problem, we utilize spread spectrum (SS), which is known as robust communication technique even through poor transmission channel. In previous study, we have already developed an ECG monitor using NF-IBC enhanced by SS. In this paper, we evaluated on structure of the reception electrode for reliable communication. Based on the evaluations with bit error rate, we suggested the reception electrode structure which can keep the communication reliability. As the results we considered that we can expand the reception electrode up to 2.25 m(2). Moreover, we proposed the structure of the reception electrodes that can keep the communication reliability. Finally we suggested how to use the SS NF-IBC vital-sign monitor in room that larger than 2.25 m(2), and we had shown the practicability of the systems.

  5. V4 receptive field dynamics as predicted by a systems-level model of visual attention using feedback from the frontal eye field.

    Science.gov (United States)

    Hamker, Fred H; Zirnsak, Marc

    2006-11-01

    Visual attention is generally considered to facilitate the processing of the attended stimulus. Its mechanisms, however, are still under debate. We have developed a systems-level model of visual attention which predicts that attentive effects emerge by the interactions between different brain areas. Recent physiological studies have provided evidence that attention also alters the receptive field structure. For example, V4 receptive fields typically shrink and shift towards the saccade target around saccade onset. We show that receptive field dynamics are inherently predicted by the mechanism of feedback in our model. According to the model an oculomotor feedback signal from an area involved in the competition for the saccade target location, e.g. the frontal eye field, enhances the gain of V4 cells. V4 receptive field dynamics can be observed after pooling the gain modulated responses to obtain a certain degree of spatial invariance. The time course of the receptive field dynamics in the model resemble those obtained from macaque V4.

  6. Spatiotemporal receptive field properties of a looming-sensitive neuron in solitarious and gregarious phases of the desert locust.

    Science.gov (United States)

    Rogers, Stephen M; Harston, George W J; Kilburn-Toppin, Fleur; Matheson, Thomas; Burrows, Malcolm; Gabbiani, Fabrizio; Krapp, Holger G

    2010-02-01

    Desert locusts (Schistocerca gregaria) can transform reversibly between the swarming gregarious phase and a solitarious phase, which avoids other locusts. This transformation entails dramatic changes in morphology, physiology, and behavior. We have used the lobula giant movement detector (LGMD) and its postsynaptic target, the descending contralateral movement detector (DCMD), which are visual interneurons that detect looming objects, to analyze how differences in the visual ecology of the two phases are served by altered neuronal function. Solitarious locusts had larger eyes and a greater degree of binocular overlap than those of gregarious locusts. The receptive field to looming stimuli had a large central region of nearly equal response spanning 120 degrees x 60 degrees in both phases. The DCMDs of gregarious locusts responded more strongly than solitarious locusts and had a small caudolateral focus of even further sensitivity. More peripherally, the response was reduced in both phases, particularly ventrally, with gregarious locusts showing greater proportional decrease. Gregarious locusts showed less habituation to repeated looming stimuli along the eye equator than did solitarious locusts. By contrast, in other parts of the receptive field the degree of habituation was similar in both phases. The receptive field organization to looming stimuli contrasts strongly with the receptive field organization of the same neurons to nonlooming local-motion stimuli, which show much more pronounced regional variation. The DCMDs of both gregarious and solitarious locusts are able to detect approaching objects from across a wide expanse of visual space, but phase-specific changes in the spatiotemporal receptive field are linked to lifestyle changes.

  7. Sexual and gender-based violence in the European asylum and reception sector: a perpetuum mobile?

    NARCIS (Netherlands)

    Keygnaert, I.; Dias, S.F.; Degomme, O.; Devillé, W.; Kennedy, P.; Kovats, A.; Meyer, S. de; Vettenburg, N.; Roelens, K.; Temmerman, M.

    2015-01-01

    Background: Refugees, asylum seekers and undocumented migrants are at risk of sexual and gender-based violence (SGBV) and subsequent ill-health in Europe; yet, European minimum reception standards do not address SGBV. Hence, this paper explores the nature of SGBV occurring in this sector and

  8. Sexual and gender-based violence in the European asylum and reception sector: a perpetuum mobile?

    NARCIS (Netherlands)

    Keygnaert, I.; Dias, S.F.; Degomme, O.; Devillé, W.; Kennedy, P.; Kováts, A.; De Meyer, S.; Vettenburg, N.; Roelens, K.; Temmerman, M.

    2014-01-01

    Background: Refugees, asylum seekers and undocumented migrants are at risk of sexual and gender-based violence (SGBV) and subsequent ill-health in Europe; yet, European minimum reception standards do not address SGBV. Hence, this paper explores the nature of SGBV occurring in this sector and

  9. Sexual and gender-based violence in the European asylum and reception sector : A perpetuum mobile?

    NARCIS (Netherlands)

    Keygnaert, Ines; Dias, Sonia F.; Degomme, Olivier; Devillé, Walter|info:eu-repo/dai/nl/217201490; Kennedy, Patricia; Kováts, András; De Meyer, Sara; Vettenburg, Nicole; Roelens, Kristien; Temmerman, Marleen

    2015-01-01

    Background: Refugees, asylum seekers and undocumented migrants are at risk of sexual and gender-based violence (SGBV) and subsequent ill-health in Europe; yet, European minimum reception standards do not address SGBV. Hence, this paper explores the nature of SGBV occurring in this sector and

  10. Visual Responses in FEF, Unlike V1, Primarily Reflect When the Visual Context Renders a Receptive Field Salient.

    Science.gov (United States)

    Joiner, Wilsaan M; Cavanaugh, James; Wurtz, Robert H; Cumming, Bruce G

    2017-10-11

    When light falls within a neuronal visual receptive field (RF) the resulting activity is referred to as the visual response. Recent work suggests this activity is in response to both the visual stimulation and the abrupt appearance, or salience, of the presentation. Here we present a novel method for distinguishing the two, based on the timing of random and nonrandom presentations. We examined these contributions in frontal eye field (FEF; N = 51) and as a comparison, an early stage in the primary visual cortex (V1; N = 15) of male monkeys (Macaca mulatta). An array of identical stimuli was presented within and outside the neuronal RF while we manipulated salience by varying the time between stimulus presentations. We hypothesized that the rapid presentation would reduce salience (the sudden appearance within the visual field) of a stimulus at any one location, and thus decrease responses driven by salience in the RF. We found that when the interstimulus interval decreased from 500 to 16 ms there was an approximate 79% reduction in the FEF response compared with an estimated 17% decrease in V1. This reduction in FEF response for rapid presentation was evident even when the random sequence preceding a stimulus did not stimulate the RF for 500 ms. The time course of these response changes in FEF suggest that salience is represented much earlier (visual system.SIGNIFICANCE STATEMENT The neuronal responses in early visual processing [e.g., primary visual cortex (V1)] reflect primarily the retinal stimulus. Processing in higher visual areas is modulated by a combination of the visual stimulation and contextual factors, such as salience, but identifying these components separately has been difficult. Here we quantified these contributions at a late stage of visual processing [frontal eye field (FEF)] and as a comparison, an early stage in V1. Our results suggest that as visual information continues through higher levels of processing the neural responses are no longer

  11. Receptive fields of locust brain neurons are matched to polarization patterns of the sky.

    Science.gov (United States)

    Bech, Miklós; Homberg, Uwe; Pfeiffer, Keram

    2014-09-22

    Many animals, including insects, are able to use celestial cues as a reference for spatial orientation and long-distance navigation [1]. In addition to direct sunlight, the chromatic gradient of the sky and its polarization pattern are suited to serve as orientation cues [2-5]. Atmospheric scattering of sunlight causes a regular pattern of E vectors in the sky, which are arranged along concentric circles around the sun [5, 6]. Although certain insects rely predominantly on sky polarization for spatial orientation [7], it has been argued that detection of celestial E vector orientation may not suffice to differentiate between solar and antisolar directions [8, 9]. We show here that polarization-sensitive (POL) neurons in the brain of the desert locust Schistocerca gregaria can overcome this ambiguity. Extracellular recordings from POL units in the central complex and lateral accessory lobes revealed E vector tunings arranged in concentric circles within large receptive fields, matching the sky polarization pattern at certain solar positions. Modeling of neuronal responses under an idealized sky polarization pattern (Rayleigh sky) suggests that these "matched filter" properties allow locusts to unambiguously determine the solar azimuth by relying solely on the sky polarization pattern for compass navigation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Delayed maturation of receptive field center/surround mechanisms in V2.

    Science.gov (United States)

    Zhang, Bin; Zheng, Jianghe; Watanabe, Ichiro; Maruko, Ichiro; Bi, Hua; Smith, Earl L; Chino, Yuzo

    2005-04-19

    Neurons in the adult visual cortex are capable of integrating signals over a large area that surrounds their classic receptive field (RF), and this ability of cortical neurons is thought to be intimately involved in perceptual binding. It is not known, however, at what age these long-range signal interactions emerge. Here, we report that qualitatively adult-like center/surround interactions are already present in the primary visual cortex as early as postnatal day 14 in macaque monkeys. However, the RF surrounds of visual area 2 (V2) neurons were largely absent until 4 weeks of age and, as late as 8 weeks of age, center/surround signal interactions in V2 neurons were immature. Our results suggest that the cortical circuits underlying the RF center/surround of individual neurons mature considerably later in V2 than in the primary visual cortex and give critical evidence for the hypothesis that the functional maturation of the primate visual brain proceeds in a hierarchical manner.

  13. Electrical receptive fields of retinal ganglion cells: Influence of presynaptic neurons.

    Science.gov (United States)

    Maturana, Matias I; Apollo, Nicholas V; Garrett, David J; Kameneva, Tatiana; Cloherty, Shaun L; Grayden, David B; Burkitt, Anthony N; Ibbotson, Michael R; Meffin, Hamish

    2018-02-01

    Implantable retinal stimulators activate surviving neurons to restore a sense of vision in people who have lost their photoreceptors through degenerative diseases. Complex spatial and temporal interactions occur in the retina during multi-electrode stimulation. Due to these complexities, most existing implants activate only a few electrodes at a time, limiting the repertoire of available stimulation patterns. Measuring the spatiotemporal interactions between electrodes and retinal cells, and incorporating them into a model may lead to improved stimulation algorithms that exploit the interactions. Here, we present a computational model that accurately predicts both the spatial and temporal nonlinear interactions of multi-electrode stimulation of rat retinal ganglion cells (RGCs). The model was verified using in vitro recordings of ON, OFF, and ON-OFF RGCs in response to subretinal multi-electrode stimulation with biphasic pulses at three stimulation frequencies (10, 20, 30 Hz). The model gives an estimate of each cell's spatiotemporal electrical receptive fields (ERFs); i.e., the pattern of stimulation leading to excitation or suppression in the neuron. All cells had excitatory ERFs and many also had suppressive sub-regions of their ERFs. We show that the nonlinearities in observed responses arise largely from activation of presynaptic interneurons. When synaptic transmission was blocked, the number of sub-regions of the ERF was reduced, usually to a single excitatory ERF. This suggests that direct cell activation can be modeled accurately by a one-dimensional model with linear interactions between electrodes, whereas indirect stimulation due to summated presynaptic responses is nonlinear.

  14. Within, but not between hands interactions in vibrotactile detection thresholds reflect somatosensory receptive field organization

    Directory of Open Access Journals (Sweden)

    Luigi eTamè

    2014-02-01

    Full Text Available Detection of a tactile stimulus on one finger is impaired when a concurrent stimulus (masker is presented on an additional finger of the same or the opposite hand. This phenomenon is known to be finger-specific at the within-hand level. However, whether this specificity is also maintained at the between-hand level is not known. In four experiments, we addressed this issue by combining a Bayesian adaptive staircase procedure (QUEST with a two-interval forced choice (2IFC design in order to establish threshold for detecting 200ms, 100Hz sinusoidal vibrations applied to the index or little fingertip of either hand (targets. We systematically varied the masker finger (index, middle, ring, or little finger of either hand, while controlling the spatial location of the target and masker stimuli. Detection thresholds varied consistently as a function of the masker finger when the latter was on the same hand (Experiments 1 and 2, but not when on different hands (Experiments 3 and 4. Within the hand, detection thresholds increased for masker fingers closest to the target finger (i.e., middle>ring when the target was index. Between the hands, detection thresholds were higher only when the masker was present on any finger as compared to when the target was presented in isolation. The within hand effect of masker finger is consistent with the segregation of different fingers at the early stages of somatosensory processing, from the periphery to the primary somatosensory cortex (SI. We propose that detection is finger-specific and reflects the organisation of somatosensory receptive fields in SI within, but not between the hands.

  15. Image identification from brain activity using the population receptive field model.

    Directory of Open Access Journals (Sweden)

    Wietske Zuiderbaan

    Full Text Available A goal of computational models is not only to explain experimental data but also to make new predictions. A current focus of computational neuroimaging is to predict features of the presented stimulus from measured brain signals. These computational neuroimaging approaches may be agnostic about the underlying neural processes or may be biologically inspired. Here, we use the biologically inspired population receptive field (pRF approach to identify presented images from fMRI recordings of the visual cortex, using an explicit model of the underlying neural response selectivity. The advantage of the pRF-model is its simplicity: it is defined by a handful of parameters, which can be estimated from fMRI data that was collected within half an hour. Using 7T MRI, we measured responses elicited by different visual stimuli: (i conventional pRF mapping stimuli, (ii semi-random synthetic images and (iii natural images. The pRF mapping stimuli were used to estimate the pRF-properties of each cortical location in early visual cortex. Next, we used these pRFs to identify which synthetic or natural images was presented to the subject from the fMRI responses. We show that image identification using V1 responses is far above chance, both for the synthetic and natural images. Thus, we can identify visual images, including natural images, using the most fundamental low-parameter pRF model estimated from conventional pRF mapping stimuli. This allows broader application of image identification.

  16. Discriminative ability of reflex receptive fields to distinguish patients with acute and chronic low back pain.

    Science.gov (United States)

    Müller, Monika; Biurrun Manresa, José A; Treichel, Fabienne; Agten, Christoph A; Heini, Paul; Andersen, Ole K; Curatolo, Michele; Jüni, Peter

    2016-12-01

    Low back pain has a life time prevalence of 70% to 85%. Approximately 10% to 20% of all patients experience recurrent episodes or develop chronic low back pain. Sociodemographic, clinical, and psychological characteristics explain the transition from acute to chronic low back pain only to a limited extent. Altered central pain processing may be a contributing mechanism. The measurement of reflex receptive fields (RRF) is a novel method to assess altered central pain processing. The RRF area denotes the area of the foot sole from which spinal nociceptive reflexes can be elicited. It was shown to be enlarged in patients with acute and chronic low back pain compared with pain-free individuals. The aim of the study was to explore the discriminative ability of the RRF to distinguish patients with acute and chronic low back pain with the hypothesis that enlarged RRF are associated with chronic low back pain. We included 214 patients with either acute or chronic low back pain and compared RRF between groups in both univariable and multivariable analyses adjusted for different sociodemographic and clinical characteristics possibly associated with the transition to chronic pain. We found a mean difference between patients with acute and chronic low back pain of -0.01 (95% confidence interval [CI], -0.06 to 0.04) in the crude, -0.02 (95% CI, -0.08 to 0.04) in the age and sex adjusted, and -0.02 (95% CI, -0.09 to 0.05) in the fully adjusted model. Our results suggest that the enlargement of RRF area may not be associated with the transition from acute to chronic low back pain.

  17. Learning Peri-saccadic Remapping of Receptive Field from Experience in Lateral Intraparietal Area

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    2017-11-01

    Full Text Available Our eyes move constantly at a frequency of 3–5 times per second. These movements, called saccades, induce the sweeping of visual images on the retina, yet we perceive the world as stable. It has been suggested that the brain achieves this visual stability via predictive remapping of neuronal receptive field (RF. A recent experimental study disclosed details of this remapping process in the lateral intraparietal area (LIP, that is, about the time of the saccade, the neuronal RF expands along the saccadic trajectory temporally, covering the current RF (CRF, the future RF (FRF, and the region the eye will sweep through during the saccade. A cortical wave (CW model was also proposed, which attributes the RF remapping as a consequence of neural activity propagating in the cortex, triggered jointly by a visual stimulus and the corollary discharge (CD signal responsible for the saccade. In this study, we investigate how this CW model is learned naturally from visual experiences at the development of the brain. We build a two-layer network, with one layer consisting of LIP neurons and the other superior colliculus (SC neurons. Initially, neuronal connections are random and non-selective. A saccade will cause a static visual image to sweep through the retina passively, creating the effect of the visual stimulus moving in the opposite direction of the saccade. According to the spiking-time-dependent-plasticity rule, the connection path in the opposite direction of the saccade between LIP neurons and the connection path from SC to LIP are enhanced. Over many such visual experiences, the CW model is developed, which generates the peri-saccadic RF remapping in LIP as observed in the experiment.

  18. English teaching based on icts for the development of reception skills in learning a foreign language

    OpenAIRE

    Ramírez Meléndez, Luz Angélica; Gallego Jaramillo, Sindy Catalina

    2012-01-01

    This is a research paper resulting from the macro-research “Interaction between ictand bilingual teaching as a functional learning alternative”, that was developed from the second semester 2010 to the first semester 2012, in the Universidad Cooperativa de Colombia, Bucaramanga. Noting the difficulties of children in listening and reading, we have based our approach in the development of receptive skills on second grade students (2-2) of the Escuela Normal Superior de Bucaramanga in order to c...

  19. Population Receptive Field Properties from fMRI and Electrocorticography in Striate and Extrastriate Cortex of the Same Subject

    Directory of Open Access Journals (Sweden)

    Ben Mark Harvey

    2012-05-01

    Full Text Available Population receptive field (pRF modelling reconstructs the properties of visually responsive neuronal populations, typically using fMRI in humans. However, fMRI is an indirect measure of neural activity. Electrocorticography (ECoG measures electrical activity directly in humans using subdural electrodes. Here, we model pRF properties using both fMRI and ECoG data from the same subject. Prior to clinical intervention, we recorded fMRI responses to visual field mapping stimuli to determine pRF properties and visual area layout. The same subject subsequently underwent surgery to implant subdural ECoG electrodes and was shown the same visual field mapping stimuli while recording ECoG signals. ECoG data were filtered into different spectral bands, which were analysed separately. ECoG electrodes were localised to V1, MT, LO2, and IPS visual areas. Gamma-band responses allowed pRF modelling in all electrodes, and beta-band responses could also be fit in V1. pRF sizes were similar between ECoG and fMRI models. V1 alpha-band amplitude was highest when the stimulus was in the inhibitory surround of the neural population, although this did not reduce the gamma signal below baseline. IPS, MT, and LO2 alpha amplitude was highest when a blank screen was displayed, which was also found in the IPS beta-band. ECoG recording produces comparable results to fMRI for pRF modelling, providing useful validation and extension of fMRI-based reconstruction of neural pRF properties. The fMRI signal cannot be explained by one ECoG spectral density band alone. Alpha band amplitudes reflect inhibitory signals in V1 and resting-state in extra-striate cortex. The same spectral band can reflect different functional processing depending on cortical location.

  20. Altered Balance of Receptive Field Excitation and Suppression in Visual Cortex of Amblyopic Macaque Monkeys.

    Science.gov (United States)

    Hallum, Luke E; Shooner, Christopher; Kumbhani, Romesh D; Kelly, Jenna G; García-Marín, Virginia; Majaj, Najib J; Movshon, J Anthony; Kiorpes, Lynne

    2017-08-23

    In amblyopia, a visual disorder caused by abnormal visual experience during development, the amblyopic eye (AE) loses visual sensitivity whereas the fellow eye (FE) is largely unaffected. Binocular vision in amblyopes is often disrupted by interocular suppression. We used 96-electrode arrays to record neurons and neuronal groups in areas V1 and V2 of six female macaque monkeys ( Macaca nemestrina ) made amblyopic by artificial strabismus or anisometropia in early life, as well as two visually normal female controls. To measure suppressive binocular interactions directly, we recorded neuronal responses to dichoptic stimulation. We stimulated both eyes simultaneously with large sinusoidal gratings, controlling their contrast independently with raised-cosine modulators of different orientations and spatial frequencies. We modeled each eye's receptive field at each cortical site using a difference of Gaussian envelopes and derived estimates of the strength of central excitation and surround suppression. We used these estimates to calculate ocular dominance separately for excitation and suppression. Excitatory drive from the FE dominated amblyopic visual cortex, especially in more severe amblyopes, but suppression from both the FE and AEs was prevalent in all animals. This imbalance created strong interocular suppression in deep amblyopes: increasing contrast in the AE decreased responses at binocular cortical sites. These response patterns reveal mechanisms that likely contribute to the interocular suppression that disrupts vision in amblyopes. SIGNIFICANCE STATEMENT Amblyopia is a developmental visual disorder that alters both monocular vision and binocular interaction. Using microelectrode arrays, we examined binocular interaction in primary visual cortex and V2 of six amblyopic macaque monkeys ( Macaca nemestrina ) and two visually normal controls. By stimulating the eyes dichoptically, we showed that, in amblyopic cortex, the binocular combination of signals is

  1. Visual cortex in aging and Alzheimer’s disease: Changes in visual field maps and population receptive fields

    Directory of Open Access Journals (Sweden)

    Alyssa A. Brewer

    2014-02-01

    Full Text Available Although several studies have suggested that cortical alterations underlie such age-related visual deficits as decreased acuity, little is known about what changes actually occur in visual cortex during healthy aging. Two recent studies showed changes in primary visual cortex (V1 during normal aging; however, no studies have characterized the effects of aging on visual cortex beyond V1, important measurements both for understanding the aging process and for comparison to changes in age-related diseases. Similarly, there is almost no information about changes in visual cortex in Alzheimer’s disease (AD, the most common form of dementia. Because visual deficits are often reported as one of the first symptoms of AD, measurements of such changes in the visual cortex of AD patients might improve our understanding of how the visual system is affected by neurodegeneration as well as aid early detection, accurate diagnosis and timely treatment of AD. Here we use fMRI to first compare the visual field map (VFM organization and population receptive fields (pRFs between young adults and healthy aging subjects for occipital VFMs V1, V2, V3, and hV4. Healthy aging subjects do not show major VFM organizational deficits, but do have reduced surface area and increased pRF sizes in the foveal representations of V1, V2, and hV4 relative to healthy young control subjects. These measurements are consistent with behavioral deficits seen in healthy aging. We then demonstrate the feasibility and first characterization of these measurements in two patients with mild AD, which reveal potential changes in visual cortex as part of the pathophysiology of AD. Our data aid in our understanding of the changes in the visual processing pathways in normal aging and provide the foundation for future research into earlier and more definitive detection of AD.

  2. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure: e1004770

    National Research Council Canada - National Science Library

    Thomas Miconi; Rufin VanRullen

    2016-01-01

      Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space...

  3. Binocular neurons in parastriate cortex: interocular 'matching' of receptive field properties, eye dominance and strength of silent suppression.

    Directory of Open Access Journals (Sweden)

    Phillip A Romo

    Full Text Available Spike-responses of single binocular neurons were recorded from a distinct part of primary visual cortex, the parastriate cortex (cytoarchitectonic area 18 of anaesthetized and immobilized domestic cats. Functional identification of neurons was based on the ratios of phase-variant (F1 component to the mean firing rate (F0 of their spike-responses to optimized (orientation, direction, spatial and temporal frequencies and size sine-wave-luminance-modulated drifting grating patches presented separately via each eye. In over 95% of neurons, the interocular differences in the phase-sensitivities (differences in F1/F0 spike-response ratios were small (≤ 0.3 and in over 80% of neurons, the interocular differences in preferred orientations were ≤ 10°. The interocular correlations of the direction selectivity indices and optimal spatial frequencies, like those of the phase sensitivies and optimal orientations, were also strong (coefficients of correlation r ≥ 0.7005. By contrast, the interocular correlations of the optimal temporal frequencies, the diameters of summation areas of the excitatory responses and suppression indices were weak (coefficients of correlation r ≤ 0.4585. In cells with high eye dominance indices (HEDI cells, the mean magnitudes of suppressions evoked by stimulation of silent, extra-classical receptive fields via the non-dominant eyes, were significantly greater than those when the stimuli were presented via the dominant eyes. We argue that the well documented 'eye-origin specific' segregation of the lateral geniculate inputs underpinning distinct eye dominance columns in primary visual cortices of mammals with frontally positioned eyes (distinct eye dominance columns, combined with significant interocular differences in the strength of silent suppressive fields, putatively contribute to binocular stereoscopic vision.

  4. Beyond Reception

    DEFF Research Database (Denmark)

    This book argues that it is time to rethink reception as a traditional paradigm for understanding the relation between the ancient Greco-Roman traditions and early Judaism and Christianity. The concept of reception implies taking something from one fixed box into another, often a chronological la...

  5. Reversible deactivation of higher-order posterior parietal areas. I. Alterations of receptive field characteristics in early stages of neocortical processing.

    Science.gov (United States)

    Cooke, Dylan F; Goldring, Adam B; Baldwin, Mary K L; Recanzone, Gregg H; Chen, Arnold; Pan, Tingrui; Simon, Scott I; Krubitzer, Leah

    2014-11-15

    Somatosensory processing in the anesthetized macaque monkey was examined by reversibly deactivating posterior parietal areas 5L and 7b and motor/premotor cortex (M1/PM) with microfluidic thermal regulators developed by our laboratories. We examined changes in receptive field size and configuration for neurons in areas 1 and 2 that occurred during and after cooling deactivation. Together the deactivated fields and areas 1 and 2 form part of a network for reaching and grasping in human and nonhuman primates. Cooling area 7b had a dramatic effect on receptive field size for neurons in areas 1 and 2, while cooling area 5 had moderate effects and cooling M1/PM had little effect. Specifically, cooling discrete locations in 7b resulted in expansions of the receptive fields for neurons in areas 1 and 2 that were greater in magnitude and occurred in a higher proportion of sites than similar changes evoked by cooling the other fields. At some sites, the neural receptive field returned to the precooling configuration within 5-22 min of rewarming, but at other sites changes in receptive fields persisted. These results indicate that there are profound top-down influences on sensory processing of early cortical areas in the somatosensory cortex. Copyright © 2014 the American Physiological Society.

  6. Development of a new comprehensive and reliable endometrial receptivity map (ER Map/ER Grade) based on RT-qPCR gene expression analysis.

    Science.gov (United States)

    Enciso, M; Carrascosa, J P; Sarasa, J; Martínez-Ortiz, P A; Munné, S; Horcajadas, J A; Aizpurua, J

    2018-02-01

    comparing LH + 2 and LH + 7 samples (paired t-test, P endometrial status (proliferative, pre-receptive, receptive and post-receptive) in both fertile and infertile groups. N/A. To evaluate the efficacy of this new tool to improve ART outcomes, further investigations such as non-selection studies and randomized controlled trials will also be required. A new comprehensive system for human endometrial receptivity evaluation based on gene expression analysis has been developed. The identification of the optimal time for embryo transfer is essential to maximize the effectiveness of ART. This study is a new step in the field of personalized medicine in human reproduction which may help in the management of endometrial preparation for embryo transfer, increasing the chances of pregnancy for many couples. The authors have no potential conflict of interest to declare. No external funding was obtained for this study.

  7. Neurocognitive Poetics: methods and models for investigating the neuronal and cognitive- affective bases of literature reception

    Directory of Open Access Journals (Sweden)

    Arthur M Jacobs

    2015-04-01

    Full Text Available A long tradition of research including classical rhetoric, aesthetics and poetics theory, formalism and structuralism, as well as current perspectives in (neurocognitive poetics has investigated structural and functional aspects of literature reception. Despite a wealth of literature published in specialised journals like Poetics, however, still little is known about how the brain processes and creates literary and poetic texts. Still, such stimulus material might be suited better than other genres for demonstrating the complexities with which our brain constructs the world in and around us, because it unifies thought and language, music and imagery in a clear, manageable way, most often with play, pleasure, and emotion (Schrott & Jacobs, 2011. In this paper, I discuss methods and models for investigating the neuronal and cognitive-affective bases of literary reading together with pertinent results from studies on poetics, text processing, emotion, or neuroaesthetics, and outline current challenges and future perspectives.

  8. Social Media-Based Civic Engagement Solutions for Dengue Prevention in Sri Lanka: Results of Receptivity Assessment

    Science.gov (United States)

    Lwin, May O.; Vijaykumar, Santosh; Foo, Schubert; Fernando, Owen Noel Newton; Lim, Gentatsu; Panchapakesan, Chitra; Wimalaratne, Prasad

    2016-01-01

    This article focuses on a novel social media-based system that addresses dengue prevention through an integration of three components: predictive surveillance, civic engagement and health education. The aim was to conduct a potential receptivity assessment of this system among smartphone users in the city of Colombo, the epicenter of the dengue…

  9. Retinal correspondence of monocular receptive fields in disparity-sensitive complex cells from area V1 in the awake monkey.

    Science.gov (United States)

    Perez, Rogelio; Castro, Adrian F; Justo, Maria S; Bermudez, Maria A; Gonzalez, Francisco

    2005-04-01

    To explore the neural mechanisms underlying disparity sensitivity in complex cells of the macaque visual cortex, the relationship between interocular receptive field (RF) positional shift and disparity sensitivity was studied in area V1. Single-unit recordings were made from area V1 of awake Macaca mulatta. Monocular RFs were mapped by means of a reverse cross-correlation technique, and their centers were determined after performing a bidimensional Gaussian function fitting. Interocular RF shifts were calculated for both bright and dark stimuli. Similarly, Gabor adjustments were obtained from disparity profiles to bright and dark dynamic random-dot stereograms (RDSs). Twenty-five complex cells were studied. The response profiles to disparity were similar for bright and dark RDSs. Interocular RF positional shift correlated significantly with both the peaks of Gabor fittings of disparity-sensitivity profiles and the peaks of the Gaussian envelopes of these Gabor fittings. Correlation between interocular RF positional shift and the peaks of the Gaussian envelopes was stronger than correlation between interocular RF positional shift and peaks of Gabor fittings. Interocular shift of monocular RFs is more related to the center of the range of disparities to which the cell is sensitive, than to the preferred disparity of the cell.

  10. A possible explanation of the low-level brightness-contrast illusions in the light of an extended classical receptive field model of retinal ganglion cells.

    Science.gov (United States)

    Ghosh, Kuntal; Sarkar, Sandip; Bhaumik, Kamales

    2006-02-01

    The low-level brightness-contrast illusions constitute a special class within visual illusions. Speculations exist that these illusions may be processed through the filtering action of the retinal ganglion cells without necessitating much intervention from higher order processes of visual perception. Concept of the classical receptive field of the ganglion cell, derived from early physiological studies, prompted the idea that a Difference of Gaussian (DoG) model might explain the low-level illusions. In spite of its many successes, the DoG model fails to explain some of these illusions. It has been shown in this paper that it is possible to simulate those illusions with a model that takes into cognizance the role of the extended classical receptive field.

  11. Nonlinear cross-frequency interactions in primary auditory cortex spectrotemporal receptive fields: a Wiener-Volterra analysis.

    Science.gov (United States)

    Pienkowski, Martin; Eggermont, Jos J

    2010-04-01

    The effects of nonlinear interactions between different sound frequencies on the responses of neurons in primary auditory cortex (AI) have only been investigated using two-tone paradigms. Here we stimulated with relatively dense, Poisson-distributed trains of tone pips (with frequency ranges spanning five octaves, 16 frequencies /octave, and mean rates of 20 or 120 pips /s), and examined within-frequency (or auto-frequency) and cross-frequency interactions in three types of AI unit responses by computing second-order "Poisson-Wiener" auto- and cross-kernels. Units were classified on the basis of their spectrotemporal receptive fields (STRFs) as "double-peaked", "single-peaked" or "peak-valley". Second-order interactions were investigated between the two bands of excitatory frequencies on double-peaked STRFs, between an excitatory band and various non-excitatory bands on single-peaked STRFs, and between an excitatory band and an inhibitory sideband on peak-valley STRFs. We found that auto-frequency interactions (i.e., those within a single excitatory band) were always characterized by a strong depression of (first-order) excitation that decayed with the interstimulus lag up to approximately 200 ms. That depression was weaker in cross-frequency compared to auto-frequency interactions for approximately 25% of dual-peaked STRFs, evidence of "combination sensitivity" for the two bands. Non-excitatory and inhibitory frequencies (on single-peaked and peak-valley STRFs, respectively) typically weakly depressed the excitatory response at short interstimulus lags (interactions with inhibitory frequencies rather than just non-excitatory ones. Finally, facilitation in single-peaked and peak-valley units decreased with increasing stimulus density. Our results indicate that the strong combination sensitivity and cross-frequency facilitation suggested by previous two-tone-paradigm studies are much less pronounced when using more temporally-dense stimuli.

  12. The visual development of hand-centered receptive fields in a neural network model of the primate visual system trained with experimentally recorded human gaze changes

    OpenAIRE

    Galeazzi, Juan M.; Navajas, Joaquin; Mender, Bedeho M. W.; Quian Quiroga, Rodrigo; Minini, Loredana; Stringer, Simon M.

    2016-01-01

    ABSTRACT Neurons have been found in the primate brain that respond to objects in specific locations in hand-centered coordinates. A key theoretical challenge is to explain how such hand-centered neuronal responses may develop through visual experience. In this paper we show how hand-centered visual receptive fields can develop using an artificial neural network model, VisNet, of the primate visual system when driven by gaze changes recorded from human test subjects as they completed a jigsaw....

  13. Different temporal bases for body and arm movements in volleyball serve reception.

    Science.gov (United States)

    Benerink, N H; Bootsma, R J; Zaal, F T J M

    2015-10-01

    In many sports, successfully intercepting a ball requires players to move both their body and their arms. Yet, studies of interception typically focus on one or the other. We performed an analysis of the moments of first foot and arm movements of elite-level volleyball players during serve reception. Video footage of five international matches of the Netherlands men's national volleyball team allowed the systematic coding and analysis of 347 different serve reception events. For each event, we identified the time of serve (TS) and time of contact (TC). Ball flight time (from TS to TC) varied between and within types of serve (power jump serves, n = 193, and jumping float serves, n = 154). Correlation analyses revealed that foot movement was initiated with respect to time from TS, while arm movement was initiated with respect to time until TC. These results suggest that whole-body and arm movements rely on different control processes. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. The Two-Dimensional Gabor Function Adapted to Natural Image Statistics: A Model of Simple-Cell Receptive Fields and Sparse Structure in Images.

    Science.gov (United States)

    Loxley, P N

    2017-10-01

    The two-dimensional Gabor function is adapted to natural image statistics, leading to a tractable probabilistic generative model that can be used to model simple cell receptive field profiles, or generate basis functions for sparse coding applications. Learning is found to be most pronounced in three Gabor function parameters representing the size and spatial frequency of the two-dimensional Gabor function and characterized by a nonuniform probability distribution with heavy tails. All three parameters are found to be strongly correlated, resulting in a basis of multiscale Gabor functions with similar aspect ratios and size-dependent spatial frequencies. A key finding is that the distribution of receptive-field sizes is scale invariant over a wide range of values, so there is no characteristic receptive field size selected by natural image statistics. The Gabor function aspect ratio is found to be approximately conserved by the learning rules and is therefore not well determined by natural image statistics. This allows for three distinct solutions: a basis of Gabor functions with sharp orientation resolution at the expense of spatial-frequency resolution, a basis of Gabor functions with sharp spatial-frequency resolution at the expense of orientation resolution, or a basis with unit aspect ratio. Arbitrary mixtures of all three cases are also possible. Two parameters controlling the shape of the marginal distributions in a probabilistic generative model fully account for all three solutions. The best-performing probabilistic generative model for sparse coding applications is found to be a gaussian copula with Pareto marginal probability density functions.

  15. Social media-based civic engagement solutions for dengue prevention in Sri Lanka: results of receptivity assessment.

    Science.gov (United States)

    Lwin, May O; Vijaykumar, Santosh; Foo, Schubert; Fernando, Owen Noel Newton; Lim, Gentatsu; Panchapakesan, Chitra; Wimalaratne, Prasad

    2016-02-01

    This article focuses on a novel social media-based system that addresses dengue prevention through an integration of three components: predictive surveillance, civic engagement and health education. The aim was to conduct a potential receptivity assessment of this system among smartphone users in the city of Colombo, the epicenter of the dengue epidemic in the island country of Sri Lanka. Grounded in Protection Motivation Theory (PMT) and using a convenience sampling approach, the cross-sectional survey assessed perceived severity (PSe), perceived susceptibility (PSu), perceived response efficacy (PRE), perceived self-efficacy (PSE) and intention-to-use (IU) among 513 individuals. The overall receptivity to the system was high with a score of >4.00 on a five-point scale. Participants belonging to younger, better educated and higher income groups reported significantly better perceptions of the efficaciousness of the system, were confident in their ability to use the system, and planned to use it in the future. PMT variables contributed significantly to regression models predicting IU. We concluded that a social media-based system for dengue prevention will be positively received among Colombo residents and a targeted, strategic health communication effort to raise dengue-related threat perceptions will be needed to encourage greater adoption and use of the system. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  16. More Gamma More Predictions: Gamma-Synchronization as a Key Mechanism for Efficient Integration of Classical Receptive Field Inputs with Surround Predictions.

    Science.gov (United States)

    Vinck, Martin; Bosman, Conrado A

    2016-01-01

    During visual stimulation, neurons in visual cortex often exhibit rhythmic and synchronous firing in the gamma-frequency (30-90 Hz) band. Whether this phenomenon plays a functional role during visual processing is not fully clear and remains heavily debated. In this article, we explore the function of gamma-synchronization in the context of predictive and efficient coding theories. These theories hold that sensory neurons utilize the statistical regularities in the natural world in order to improve the efficiency of the neural code, and to optimize the inference of the stimulus causes of the sensory data. In visual cortex, this relies on the integration of classical receptive field (CRF) data with predictions from the surround. Here we outline two main hypotheses about gamma-synchronization in visual cortex. First, we hypothesize that the precision of gamma-synchronization reflects the extent to which CRF data can be accurately predicted by the surround. Second, we hypothesize that different cortical columns synchronize to the extent that they accurately predict each other's CRF visual input. We argue that these two hypotheses can account for a large number of empirical observations made on the stimulus dependencies of gamma-synchronization. Furthermore, we show that they are consistent with the known laminar dependencies of gamma-synchronization and the spatial profile of intercolumnar gamma-synchronization, as well as the dependence of gamma-synchronization on experience and development. Based on our two main hypotheses, we outline two additional hypotheses. First, we hypothesize that the precision of gamma-synchronization shows, in general, a negative dependence on RF size. In support, we review evidence showing that gamma-synchronization decreases in strength along the visual hierarchy, and tends to be more prominent in species with small V1 RFs. Second, we hypothesize that gamma-synchronized network dynamics facilitate the emergence of spiking output that is

  17. Post eye-opening maturation of visual receptive field diameters in the superior colliculus of normal- and dark-reared rats.

    Science.gov (United States)

    Binns, K E; Salt, T E

    1997-04-18

    When the rat's eyes open (P14) the retino-collicular projection is largely mature but the cortico-collicular afferents are naive and mature considerably in the following week. At P14, single units in the superior colliculus' superficial grey layer (SGS) had discrete receptive fields (RFs) (diameter = 15 +/- 1.6 degrees) which expanded with age, reaching 30 +/- 2.6 degrees at P21, possibly reflecting the increasing influence of the visual cortex, whose RFs are known to be enlarged at P21. Subsequently SGS RFs retracted to 13 +/- 1.3 degrees by P23. Dark-reared (DR) rats followed a similar but delayed developmental pattern, such that RFs were still large (27 +/- 3.4 degrees) at P24. By P30 however the RFs of DR rats were the same as those of normal adults. Thus visual experience accelerates the emergence of normal RFs in the SGS.

  18. A 2 x 2 imaging MIMO system based on LED Visible Light Communications employing space balanced coding and integrated PIN array reception

    DEFF Research Database (Denmark)

    Li, Jiehui; Xu, Yinfan; Shi, Jianyang

    2016-01-01

    In this paper, we proposed a 2 x 2 imaging Multi-Input Multi-Output (MIMO)-Visible Light Communication (VLC) system by employing Space Balanced Coding (SBC) based on two RGB LEDs and integrated PIN array reception. We experimentally demonstrated 1.4-Gbit/s VLC transmission at a distance of 2.5 m...

  19. Receptivity and judgment

    Directory of Open Access Journals (Sweden)

    Jennifer Nedelsky

    2011-12-01

    Full Text Available Both judgment and receptivity are important to optimal politics, and both are important to each other. In making this argument, I use an Arendtian conception of judgment and take mindfulness as an example of receptivity. I argue that receptivity offers a needed dimension to addressing the puzzles of what makes Arendtian judgment possible, and that judgment provides a necessary complement to receptivity for action in the world. Exploring this complementary relation between judgment and receptivity also reveals a surprising similarity between what each offers to the practice of politics, in particular to freedom and the possibility of transformation. At the same time, I argue, these important contributions to politics are best understood and realized if judgment and receptivity are thought of as distinct forms of relating to the world.

  20. Architectural design of a ground-based deep-space optical reception antenna

    Science.gov (United States)

    Kerr, E. L.

    1989-01-01

    An architectural design of a ground-based antenna (telescope) for receiving optical communications from deep space is presented. Physical and optical parameters, and their effect on the performance and cost considerations, are described. The channel capacity of the antenna is 100 kbits/s from Saturn and 5 Mbits/s from Mars. A novel sunshade is designed to permit optical communication even when the deep-space laser source is as close to the sun as 12 deg. Inserts in the tubes of the sunshade permit operations at solar elongations as small as 6 or 3 deg. The Nd:YAG source laser and the Fraunhofer filter (a narrow-band predetection optical filter) are tuned to match the Doppler shifts of the source and background. A typical Saturn-to-earth data link can reduce its source power requirement from 8.2 W to 2 W of laser output by employing a Fraunhofer filter instead of a conventional multilayer dielectric filter.

  1. Receptive processer og IT

    DEFF Research Database (Denmark)

    Ambjørn, Lone

    2002-01-01

    Sproglæringsteoretisk værktøj til udvikling af IT-støttede materialer og programmer inden for sproglig reception......Sproglæringsteoretisk værktøj til udvikling af IT-støttede materialer og programmer inden for sproglig reception...

  2. The visual development of hand-centered receptive fields in a neural network model of the primate visual system trained with experimentally recorded human gaze changes.

    Science.gov (United States)

    Galeazzi, Juan M; Navajas, Joaquín; Mender, Bedeho M W; Quian Quiroga, Rodrigo; Minini, Loredana; Stringer, Simon M

    2016-01-01

    Neurons have been found in the primate brain that respond to objects in specific locations in hand-centered coordinates. A key theoretical challenge is to explain how such hand-centered neuronal responses may develop through visual experience. In this paper we show how hand-centered visual receptive fields can develop using an artificial neural network model, VisNet, of the primate visual system when driven by gaze changes recorded from human test subjects as they completed a jigsaw. A camera mounted on the head captured images of the hand and jigsaw, while eye movements were recorded using an eye-tracking device. This combination of data allowed us to reconstruct the retinal images seen as humans undertook the jigsaw task. These retinal images were then fed into the neural network model during self-organization of its synaptic connectivity using a biologically plausible trace learning rule. A trace learning mechanism encourages neurons in the model to learn to respond to input images that tend to occur in close temporal proximity. In the data recorded from human subjects, we found that the participant's gaze often shifted through a sequence of locations around a fixed spatial configuration of the hand and one of the jigsaw pieces. In this case, trace learning should bind these retinal images together onto the same subset of output neurons. The simulation results consequently confirmed that some cells learned to respond selectively to the hand and a jigsaw piece in a fixed spatial configuration across different retinal views.

  3. Receptiveness and humanization from the perspective of anesthesiologists.

    Science.gov (United States)

    Santos, Maria de Fátima Oliveira dos; Fernandes, Maria das Graças Melo; Oliveira, Harison José de

    2012-01-01

    Receptiveness is a tool that brings contributions for health care humanization, especially with regard to its practice in the field of Anesthesiology. The aim was to investigate through the report of anesthesiologists the understanding of the receptiveness phenomenon among these professionals. This is a descriptive qualitative research held at the Hospital Universitário Lauro Wanderley (HULW), in the city of João Pessoa, PB. The sample consisted of 16 attending anesthesiologists, 25% female doctors and 75% male doctors. Data were collected through interviews guided by two semi-structured questions from September to October 2010. Data analysis was performed using the technique of Collective Subject Discourse (CSD). The anesthesiologists' answer to the following question was considered as this study's result: "What do you think about the practice of receptiveness as a strategy to humanize the doctor-patient relationship?" The doctors' CSD presented two central ideas: 1) a holistic approach to the patient; 2) a strategy that improves the doctor-patient relationship. When asked about the strategies adopted by them to humanize the relationship with the patient at the time of reception, their reports were organized based on three central ideas: 1) observation of patients' rights; 2) therapeutic communication; 3) preanesthetic visit. It was found that the physicians involved in the research recognized the value of receptiveness as a strategy to humanize the doctor-patient relationship. The receptivity to the patient in the course of anesthesia is very important because it allows the professional to perform a qualified hearing of the patient's history, together with the humanized care process, which enables the improvement of the interaction between doctor and patient. Copyright © 2012 Elsevier Editora Ltda. All rights reserved.

  4. The Reception Learning Paradigm.

    Science.gov (United States)

    Novak, Joseph D.

    1979-01-01

    Presented is a paradigm for science education research. The paradigm advances the reception learning theory, where regularities to be learned are presented explicitly to the learner. A tool for the study of knowledge production in science education, the Gowin "V," is presented. (RE)

  5. Measuring Users' Receptivity Toward an Integral Intervention Model Based on mHealth Solutions for Patients With Treatment-Resistant Schizophrenia (m-RESIST): A Qualitative Study.

    Science.gov (United States)

    Huerta-Ramos, Elena; Escobar-Villegas, Maria Soledad; Rubinstein, Katya; Unoka, Zsolt Szabolcs; Grasa, Eva; Hospedales, Margarita; Jääskeläinen, Erika; Rubio-Abadal, Elena; Caspi, Asaf; Bitter, István; Berdun, Jesus; Seppälä, Jussi; Ochoa, Susana; Fazekas, Kata; Corripio, Iluminada; Usall, Judith

    2016-09-28

    Despite the theoretical potential of mHealth solutions in the treatment of patients with schizophrenia, there remains a lack of technological tools in clinical practice. The aim of this study was to measure the receptivity of patients, informal carers, and clinicians to a European integral intervention model focused on patients with persistent positive symptoms: Mobile Therapeutic Attention for Patients with Treatment-Resistant Schizophrenia (m-RESIST). Before defining the system requirements, a qualitative study of the needs of outpatients with treatment-resistant schizophrenia was carried out in Spain, Israel, and Hungary. We analyzed the opinions of patients, informal carers, and clinicians concerning the services originally intended to be part of the solution. A total of 9 focus groups (72 people) and 35 individual interviews were carried out in the 3 countries, using discourse analysis as the framework. A webpage and an online forum were perceived as suitable to get both reliable information on the disease and support. Data transmission by a smart watch (monitoring), Web-based visits, and instant messages (clinical treatment) were valued as ways to improve contact with clinicians. Alerts were appreciated as reminders of daily tasks and appointments. Avoiding stressful situations for outpatients, promoting an active role in the management of the disease, and maintaining human contact with clinicians were the main suggestions provided for improving the effectiveness of the solution. Positive receptivity toward m-RESIST services is related to its usefulness in meeting user needs, its capacity to empower them, and the possibility of maintaining human contact.

  6. Predicting Volleyball Serve-Reception

    NARCIS (Netherlands)

    Paulo, Ana; Zaal, Frank T J M; Fonseca, Sofia; Araujo, Duarte

    2016-01-01

    Serve and serve-reception performance have predicted success in volleyball. Given the impact of serve-reception on the game, we aimed at understanding what it is in the serve and receiver's actions that determines the selection of the type of pass used in serve-reception and its efficacy. Four

  7. Evaluation of pollen viability, stigma receptivity and fertilization ...

    African Journals Online (AJOL)

    To provide theoretical basis for artificial pollination in Lagerstroemia indica L., pollen viability and stigma receptivity were tested and the morphological change of stigma was observed. Pollen viability tested by in vitro culture, stigma receptivity examined by benzidine-H2O2 testing and fruit set estimated by field artificial ...

  8. Reception Shop Special Stand

    CERN Multimedia

    Education and Technology Transfer Unit/ETT-EC

    2004-01-01

    Friday 15.10.2004 CERN 50th Anniversary articles will be sold in the Main Building, ground floor on Friday 15th October from 10h00 to 16h00. T-shirt, (S, M, L, XL) 20.- K-way (M, L, XL) 20.- Silk tie (2 models) 30.- Einstein tie 45.- Umbrella 20.- Caran d'Ache pen 5.- 50th Anniversary Pen 5.- Kit of Cartoon Album & Crayons 10.- All the articles are also available at the Reception Shop in Building 33 from Monday to Saturday between 08.30 and 17.00 hrs. Education and Technology Transfer Unit/ETT-EC

  9. Reception research 2.0

    DEFF Research Database (Denmark)

    Mathieu, David

    Some might argue that reception analysis is a remnant of the past in an age where “people formerly known as the audience” (Rosen, 2006) are producing and circulating content on a diversity of interactive and participatory media platforms. Far from being the case, reception research must continue...... on social media can help us better understand the participatory media culture that has established itself over the past decade. To properly address the question of meaning, however, reception research needs to be adapted to the current media landscape. Taking my point of departure in the multi...... (motivation, comprehension, discrimination, position, implementation) for their relevance and explanatory power in today’s media landscape, suggesting new interpretations and new formulations. A revision of reception research does not only concern the notion of reception itself, but also that of the text...

  10. Predicting Volleyball Serve-reception

    Directory of Open Access Journals (Sweden)

    Ana Paulo

    2016-11-01

    Full Text Available Serve and serve-reception performance have predicted success in volleyball. Given the impact of serve-reception on the game, we aimed at understanding what it is in the serve and receiver’s actions that determines the selection of the type of pass used in serve-reception and its efficacy. Four high-level players received jump-float serves from four servers in two reception zones – zone 1 and 5. The ball and the receiver’s head were tracked with two video cameras, allowing 3D world-coordinates reconstruction. Logistic-regression models were used to predict the type of pass used (overhand or underhand and serve-reception efficacy (error, out, or effective from variables related with the serve kinematics and related with the receiver’s on-court positioning and movement. Receivers’ initial position was different when in zone 1 and 5. This influenced the serve-related variables as well as the type of pass used. Strong predictors of using an underhand rather than overhand pass were higher ball contact of the server, reception in zone 1, receiver’s initial position more to the back of the court and backward receiver movement. Receiver’s larger longitudinal displacements and an initial position more to the back of the court had a strong relationship with the decreasing of the serve-reception efficacy. Receivers’ positioning and movement were the factors with the largest impact on the type of pass used and the efficacy of the reception. Reception zone affected the variance in the ball’s kinematics (with the exception of the ball’s lateral displacement, as well as in the receivers’ positioning (distances from the net and from the target. Also the reception zone was associated with the type of pass used by the receiver but not with reception efficacy. Given volleyball’s rotation rule, the receiver needs to master receiving in the different reception zones; he/she needs to adapt to the diverse constraints of each zone to maintain

  11. Predicting Volleyball Serve-Reception

    Science.gov (United States)

    Paulo, Ana; Zaal, Frank T. J. M.; Fonseca, Sofia; Araújo, Duarte

    2016-01-01

    Serve and serve-reception performance have predicted success in volleyball. Given the impact of serve-reception on the game, we aimed at understanding what it is in the serve and receiver's actions that determines the selection of the type of pass used in serve-reception and its efficacy. Four high-level volleyball players received jump-float serves from four servers in two reception zones—zone 1 and 5. The ball and the receiver's head were tracked with two video cameras, allowing 3D world-coordinates reconstruction. Logistic-regression models were used to predict the type of pass used (overhand or underhand) and serve-reception efficacy (error, out, or effective) from variables related with the serve kinematics and related with the receiver's on-court positioning and movement. Receivers' initial position was different when in zone 1 and 5. This influenced the serve-related variables as well as the type of pass used. Strong predictors of using an underhand rather than overhand pass were higher ball contact of the server, reception in zone 1, receiver's initial position more to the back of the court and backward receiver movement. Receiver's larger longitudinal displacements and an initial position more to the back of the court had a strong relationship with the decreasing of the serve-reception efficacy. Receivers' positioning and movement were the factors with the largest impact on the type of pass used and the efficacy of the reception. Reception zone affected the variance in the ball's kinematics (with the exception of the ball's lateral displacement), as well as in the receivers' positioning (distances from the net and from the target). Also the reception zone was associated with the type of pass used by the receiver but not with reception efficacy. Given volleyball's rotation rule, the receiver needs to master receiving in the different reception zones; he/she needs to adapt to the diverse constraints of each zone to maintain performance efficacy. Thus

  12. [Delegates at the President's Reception

    OpenAIRE

    Cooper, Neil, fl 1983-2004, photographer

    2004-01-01

    A slide showing Indira Gandhi, Indian Prime Minister and Chair of the Conference, Kenneth Kaunda, President of Zambia, and Robert and Sally Mugabe, President and First Lady of Zimbabwe, in discussion at the President's Reception.

  13. New Year’s reception

    CERN Multimedia

    2009-01-01

    At a reception on 28 January, the CERN management presented their best wishes for 2009 to politicians and representatives of the administrations in the local area, and diplomats representing CERN’s Member States, Observer States and other countries.

  14. Field-based transformation optics

    DEFF Research Database (Denmark)

    Novitsky, Andrey

    2011-01-01

    Instead of common definition of the transformation-optics devices via the coordinate transformation we offer the approach founded on boundary conditions for the fields. We demonstrate the effectiveness of the approach by two examples: two-shell cloak and concentrator of electric field. We believe...

  15. [Turkish expressive and receptive language test: I. Standardization, reliability and validity study of the receptive vocabulary sub-scale].

    Science.gov (United States)

    Kazak Berument, Sibel; Güven, Ayşe Gül

    2013-01-01

    A reliable, valid and original test to assess the receptive vocabulary skills of children in Turkey was not available. Thus, the purpose of the current study was to develop a receptive vocabulary test for Turkish children based on the Turkish language. For the Receptive Vocabulary Sub-Scale (TIFALDI-RT) 242 concrete and abstract words were chosen from word frequency lists and a comprehensive Turkish Dictionary. Pilot data were collected from 648 children aged 2 to 13 from Ankara, and norm data were collected from a nationally representative sample of 3755 children. Item analysis (item difficulty, discrimination and distractor) was carried out on the pilot data and based on the results, the total item number was reduced to 157. Further, three parameter item analyses (IRT) were carried out on the norm data by using BILOG-MG (SSI, 2002), and the results indicated that the TIFALDI Receptive Vocabulary Sub-Scale could be reduced to 104 items to assess 2 to 12 year-old children's receptive vocabulary. Test-retest and internal consistency reliabilities were calculated for the whole sample and age groups separately, and all the coefficients were high. For the validity, the relationship between the WISC-R and Ankara Developmental Screening Inventory (AGTE) and Receptive Vocabulary Sub-Scale were investigated. Once again, the TIFALDI Receptive Vocabulary Sub-Scale scores were found to be significantly related to WISC-R and AGTE scores. The TIFALDI Receptive Vocabulary Sub-Scale was developed on the basis of the Turkish Language and norm data were collected from a nationally representative sample. The TIFALDI-RT also had a high reliability and validity. Thus, the TIFALDI-RT can be used to assess 2 to 12 year-old children's receptive vocabulary skills.

  16. [Mechanism of intermolecular energy transfer and reception of ultralow action by chemical and biological systems].

    Science.gov (United States)

    Gall', L N; Gall', N R

    2009-01-01

    A novel concept of intermolecular energy transfer and reception of the ultralow action in living systems is proposed. The concept is based on the methods of nonlinear mathematical physics used in description of energy movement along molecular chains and on quantum mechanical ideas concerning signal formation in anisotropic media. A concept of a molecular cell as an indivisible structural unit and a constituent of a biological (chemical) system has been put forward and substantiated, which manifests collective features of the unity of molecules, physical fields, and energetically strained bound water media in processes of energy transfer and reception. Both intermolecular energy transfer and amplification of the ultralow action has been shown to be the components of a unified energy process in a living system, and the physical basis of both processes is the unity of molecules and water-field media in a molecular cell.

  17. Prediction of turning stability using receptance coupling

    Science.gov (United States)

    Jasiewicz, Marcin; Powałka, Bartosz

    2018-01-01

    This paper presents an issue of machining stability prediction of dynamic "lathe - workpiece" system evaluated using receptance coupling method. Dynamic properties of the lathe components (the spindle and the tailstock) are assumed to be constant and can be determined experimentally based on the results of the impact test. Hence, the variable of the system "machine tool - holder - workpiece" is the machined part, which can be easily modelled analytically. The method of receptance coupling enables a synthesis of experimental (spindle, tailstock) and analytical (machined part) models, so impact testing of the entire system becomes unnecessary. The paper presents methodology of analytical and experimental models synthesis, evaluation of the stability lobes and experimental validation procedure involving both the determination of the dynamic properties of the system and cutting tests. In the summary the experimental verification results would be presented and discussed.

  18. Transducer project and optimization of the ultra low magnetic field NMR tomograph reception system system; Projeto de transdutores e otimizacao do sistema de recepcao do tomografo de RMN de campo magnetico ultra baixo

    Energy Technology Data Exchange (ETDEWEB)

    Vidoto, Edson Luiz Gea

    1995-12-31

    The aim of the present work was to optimize the signal to noise ratio in our NMR imaging system (TORM 005) by improving transducer`s reception quality through better designed coils, balanced tuning circuit for this coils and power decoupling circuits and by reducing interference from the electromagnetic environment. For this purpose, we had to modify the internal electromagnetic shielding and incorporate line filters in the more critical signals paths. Also, new types of coils were developed, improving the signal to noise ratio, and allowing us to make clinical exams with superior quality for several anatomies. Balanced circuits for tuning and matching of the coil were studied and built, allowing a reduction of the coil losses because patient`s load. This produced a more reliable coil tuning after positioning each new patient. Circuits to avoid the receiver input overload and decoupling circuits for the isolation of receiver coils from excitation coil were designed and incorporated to the TORM 005. All these alterations of our imaging system (TORM 005) contributed to a significant improvement in the signal to noise ratio, reliability and reproducibility of the system. This permitted to operate the system routinely for clinical applications, research and development in the area of ultra low magnetic field tomography. (author) 46 refs., 66 figs., 11 tabs.

  19. The Design and Implementation of Indoor Localization System Using Magnetic Field Based on Smartphone

    Science.gov (United States)

    Liu, J.; Jiang, C.; Shi, Z.

    2017-09-01

    Sufficient signal nodes are mostly required to implement indoor localization in mainstream research. Magnetic field take advantage of high precision, stable and reliability, and the reception of magnetic field signals is reliable and uncomplicated, it could be realized by geomagnetic sensor on smartphone, without external device. After the study of indoor positioning technologies, choose the geomagnetic field data as fingerprints to design an indoor localization system based on smartphone. A localization algorithm that appropriate geomagnetic matching is designed, and present filtering algorithm and algorithm for coordinate conversion. With the implement of plot geomagnetic fingerprints, the indoor positioning of smartphone without depending on external devices can be achieved. Finally, an indoor positioning system which is based on Android platform is successfully designed, through the experiments, proved the capability and effectiveness of indoor localization algorithm.

  20. From conciliar ecumenism to transformative receptive ecumenism

    Directory of Open Access Journals (Sweden)

    Mary-Anne Plaatjies van Huffel

    2017-09-01

    Full Text Available This article attends to ecumenicity as the second reformation. The ecumenical organisations and agencies hugely influenced the theological praxis and reflection of the church during the past century. The First World Council of Churches (WCC Assembly in Amsterdam, the Netherlands, has been described as the most significant event in church history since the Reformation during the past decade. We saw the emergence of two initiatives that are going to influence ecumenical theology and practice in future, namely the Receptive Ecumenism and Catholic Learning research project, based in Durham, United Kingdom, and the International Theological Colloquium for Transformative Ecumenism of the WCC. Both initiatives constitute a fresh approach in methodology to ecumenical theology and practice. Attention will be given in this article to conciliar ecumenism, receptive ecumenism, transformative ecumenism and its implications for the development of an African transformative receptive ecumenism. In doing so, we should take cognisance of what Küng says about a confessionalist ghetto mentality: ‘We must avoid a confessionalistic ghetto mentality. Instead we should espouse an ecumenical vision that takes into consideration the world religions as well as contemporary ideologies: as much tolerance as possible toward those things outside the Church, toward the religious in general, and the human in general, and the development of that which is specifically Christian belong together!’

  1. Communication from Goods Reception services

    CERN Document Server

    2007-01-01

    Members of the personnel are invited to take note that only parcels corresponding to official orders or contracts will be handled at CERN. Individuals are not authorised to have private merchandise delivered to them at CERN and private deliveries will not be accepted by the Goods Reception services. Thank you for your understanding.

  2. Sexual conflict over floral receptivity.

    Science.gov (United States)

    Lankinen, Asa; Hellriegel, Barbara; Bernasconi, Giorgina

    2006-12-01

    In flowering plants, the onset and duration of female receptivity vary among species. In several species the receptive structures wilt upon pollination. Here we explore the hypothesis that postpollination wilting may be influenced by pollen and serve as a general means to secure paternity of the pollen donor at the expense of female fitness. Taking a game-theoretical approach, we examine the potential for the evolution of a pollen-borne wilting substance, and for the coevolution of a defense strategy by the recipient plant. The model without defense predicts an evolutionarily stable strategy (ESS) for the production of wilting substance. The ESS value is highest when pollinator visiting rates are intermediate and when the probability that pollen from several donors arrives at the same time is low. This finding has general implications in that it shows that male traits to secure paternity also can evolve in species, such as plants, where mating is not strictly sequential. We further model coevolution of the wilting substance with the timing of stigma receptivity. We assume that pollen-receiving plants can reduce the costs induced by toxic pollen by delaying the onset of stigmatic receptivity. The model predicts a joint ESS, but no female counter-adaptation when the wilting substance is highly toxic. This indicates that toxicity affects the probability that a male manipulative trait stays beneficial (i.e., not countered by female defense) over evolutionary time. We discuss parallels to male induced changes in female receptivity known to occur in animals and the role of harm for the evolution of male manipulative adaptations.

  3. Measuring receptive collocational competence across proficiency ...

    African Journals Online (AJOL)

    The present study investigates (i) English as Foreign Language (EFL) learners' receptive collocational knowledge growth in relation to their linguistic proficiency level; (ii) how much receptive collocational knowledge is acquired as linguistic proficiency develops; and (iii) the extent to which receptive knowledge of ...

  4. A new service offered by rural environment to the city: stormwater reception.

    Science.gov (United States)

    Chiaradia, Enrico Antonio; Weber, Enrico; Masseroni, Daniele; Battista Bischetti, Gian; Gandolfi, Claudio

    2017-04-01

    Stormwaters are the main cause of urban floods in many urbanized areas. Historically, stormwater management practices have been focused on building infrastructures that achieve runoff attenuation through the storage of water volumes in large detention basins. However, this approach has proven to be insufficient to resolve the problem as well as it is difficult to implement in areas with a dense urban fabric. Nowadays, around the world, water managers are increasingly embracing "soft path" approaches, that aim to manage the excess of urban runoff through Green Infrastructures, where detention capacities are provided by the retention proprieties of soil and vegetation elements. Along the line of these new sustainable stormwater management practices, the aim of this study is to promote a further paradigm-shift with respect to the traditional practices i.e. to investigate the possibility to use the already existing green infrastructures of the peri-urban rural areas as reception element of the surplus of urban runoff. Many territories in Northern Italy, for example. are characterized by a high density of irrigation canals and agricultural fields that, in some cases, are isolated or pent-up inside urbanized areas. Both these elements may represent storage volumes for accumulating stormwater from urban areas. In this work, we implemented a holistic framework, based on Self Organized Map technique (SOM), with the objective to produce a spatial map of the stormwater reception level that can be provided by the rural environment. We elaborated physiographic characteristics of irrigation canals and agricultural fields through the SOM algorithm obtaining as output a series of cluster groups with the same level of receptivity. This procedure was applied on an area of 1933 km2 around the city of Milan and a map of 250x250m resolution was obtained with three different levels of stormwater reception capacity. About 50% of rural environment has a good level of reception and only 30

  5. Compressibility effects on the non-linear receptivity of boundary layers to dielectric barrier discharges

    Science.gov (United States)

    Denison, Marie F. C.

    The reduction of drag and aerodynamic heating caused by boundary layer transition is of central interest for the development of hypersonic vehicles. Receptivity to flow perturbation in the form of Tollmien-Schlichting (TS) wave growth often determines the first stage of the transition process, which can be delayed by depositing specific excitations into the boundary layer. Weakly ionized Dielectric Barrier Discharge (DBD) actuators are being investigated as possible sources of such excitations, but little is known today about their interaction with high-speed flows. In this framework, the first part of the thesis is dedicated to a receptivity study of laminar compressible boundary layers over a flat plate by linear stability analysis following an adjoint operator formulation, under DBD representative excitations assumed independent of flow conditions. The second part of the work concentrates on the development of a coupled plasma-Navier and Stokes solver targeted at the study of supersonic flow and compressibility effects on DBD forcing and non-parallel receptivity. The linear receptivity study of quasi-parallel compressible flows reveals several interesting features such as a significant shift of the region of maximum receptivity deeper into the flow at high Mach number and strong wave amplitude reduction compared to incompressible flows. The response to DBD relevant excitation distributions and to variations of the base flow conditions and system length scales follows these trends. Observed absolute amplitude changes and relative sensitivity modifications between source types are related to the evolution of the offset between forcing peak profile and relevant adjoint mode maximum. The analysis highlights the crucial importance of designing and placing the actuator in a way that matches its force field to the position of maximum boundary layer receptivity for the specific flow conditions of interest. In order to address the broad time and length scale spectrum

  6. Diverse Contexts of Reception and Feelings of Belonging

    Directory of Open Access Journals (Sweden)

    Alex Stepick

    2009-09-01

    Full Text Available The theoretical focus of this paper is the context of reception experienced by migrants in their new homeland. In particular we examine relations between established residents and newcomers or immigrants from Cuba, Haiti, and other Caribbean and Latin American nations in South Florida. Based upon long term fieldwork among late adolescents and young adults, we develop a framework and give ethnographic examples of established resident-newcomer relations that influence the contexts of reception for immigrants in South Florida. These contexts range from positive to negative, vary between national and local settings, and change over time. URN: urn:nbn:de:0114-fqs0903156

  7. ANTHROPOLOGICAL DESCARTES’ RATIONALISM AND IT'S HUSSERL’S RECEPTION

    Directory of Open Access Journals (Sweden)

    Anatolii M. Malivskyi

    2016-06-01

    Full Text Available Purpose. The article is aimed to figure out the features of Husserl's reception of anthropological Descartes rationalism. Its implementation requires a consistent solution of the following tasks: 1 schematically express a modern vision of the basic intentions of philosophizing as an anthropological rationalism; 2 highlight the main points of the Husserl's reception of Descartes’ rationalism as the deanthropologizing and analyze radicalization of its basic design as the reanthropologizing. Conclusions. When clarifying the question of the method of reception and completion of the philosophical Descartes’ project in the doctrine of Edmund Husserl, the author finds that the originality of his reception of anthropological Descartes’ rationalism appears as the paradoxical union of denying the existence of anthropology in the base project and the rediscovery of its key role in the radicalization of Descartes. Thinking of its way, he comes to the rediscovery some of the key ideas of the French philosopher, rooted in his anthropological rationalism. Among them is the basic intention of the ambivalence, the rejection of Descartes’ ideas of panrationalism, recognition irreducibility of philosophical method to the mathematical, constitutive of human presence in the new rationalism. Prospects for further research in understanding the author sees a meaningful relationship and continuity of the two great thinkers - namely, the personal nature of philosophizing and the ethical focus of their searching. Originality. Appeal to the reception of Husserl's Cartesian project confirms the thesis of an essential importance for the basic anthropological project of Descartes. The presented version of Husserl reception base project Descartes is a reproduction of the surface age stereotypes, which link the quest of the philosopher with the natural sciences and neglected anthropological measurements. The proposed version of the radicalization of Descartes’ project

  8. Let them speak: using reception analysis to understand children's relationship with fiction

    National Research Council Canada - National Science Library

    O'Shea, Cathy

    2015-01-01

    .... This article argues that reception analysis, developed in the field of cultural studies, could be usefully applied to children and their reading of fiction, as it offers a particular understanding of media audiences...

  9. Adolescent Weight Status and Receptivity to Food TV Advertisements

    Science.gov (United States)

    Adachi-Mejia, Anna M.; Sutherland, Lisa A.; Longacre, Meghan R.; Beach, Michael L.; Titus-Ernstoff, Linda; Gibson, Jennifer J.; Dalton, Madeline A.

    2011-01-01

    Objective: This study examined the relationship between adolescent weight status and food advertisement receptivity. Design: Survey-based evaluation with data collected at baseline (initial and at 2 months), and at follow-up (11 months). Setting: New Hampshire and Vermont. Participants: Students (n = 2,281) aged 10-13 in 2002-2005. Main Outcome…

  10. Refugee Perceptions of the Port Elizabeth Refugee Reception Centre

    African Journals Online (AJOL)

    This article presents findings from an empirical survey conducted at the Nelson Mandela University Refugee Rights Centre based at the Nelson Mandela Metropolitan University in Port Elizabeth, to establish the perceptions and experiences of refugees/asylum seekers of the Refugee Reception Centre in Port Elizabeth in ...

  11. The Judaeo-Karaite Reception of the Hebrew Bible

    DEFF Research Database (Denmark)

    Sabih, Joshua

    DESCRIPTION: The Karaites emerged as a school of thought within Middle Eastern Judaism in the 8th century. The Karaites were a “reading community” whose intellectual activity and daily lives were based around the divine scriptures. Over time Karaism became one of the two main competing schools of...... between the Rabbinate and the Karaite reception and interpretation of the Hebrew Bible....

  12. THE AUDIT OF RECEPTION PROCESS

    Directory of Open Access Journals (Sweden)

    Dorina MOCUŢA

    2013-01-01

    Full Text Available The object of study case is to analyze the quality of the logistics department, focusing on the audit process. Purpose of this paper is to present the advantages resulting from the systematic audit processes and methods of analysis and improvement of nonconformities found. The case study is realised at SC Miele Tehnica SRL Brasov, twelfth production line, and the fourth from outside Germany. The specific objectives are: clarifying the concept of audit quality, emphasizing requirements ISO 19011:2003 "Guidelines for auditing quality management systems and / or environment" on audits; cchieving quality audit and performance analysis; improved process performance reception materials; compliance with legislation and auditing standards applicable in EU and Romania.

  13. Magnetic field mapper based on rotating coils

    CERN Document Server

    AUTHOR|(CDS)2087244; Arpaia, Pasquale

    This thesis presents a magnetic field mapper based on rotating coils. The requirements, the architecture, the conceptual design, and the prototype for straight magnets were shown. The proposed system is made up of a rotating coil transducer and a train-like system for longitudinal motion and positioning inside magnet bore. The mapper allows a localized measurement of magnetic fields and the variation of the harmonic multipole content in the magnet ends. The proof-of-principle demonstration and the experimental characterization of the rotating-coil transducer specifically conceived for mapping validated the main objective of satisfying the magnetic measurement needs of the next generation of compact accelerators.

  14. Note from the Goods Reception services

    CERN Document Server

    FI Department

    2008-01-01

    Members of the personnel are invited to take note that only parcels corresponding to official orders or contracts will be handled at CERN. Individuals are not authorised to have private merchandise delivered to them at CERN and private deliveries will not be accepted by the Goods Reception services. Goods Reception Services

  15. Receptive prosody in nonfluent primary progressive aphasias

    Science.gov (United States)

    Rohrer, Jonathan D.; Sauter, Disa; Scott, Sophie; Rossor, Martin N.; Warren, Jason D.

    2012-01-01

    Introduction Prosody has been little studied in the primary progressive aphasias (PPAs), a group of neurodegenerative disorders presenting with progressive language impairment. Methods Here we conducted a systematic investigation of different dimensions of prosody processing (acoustic, linguistic and emotional) in a cohort of 19 patients with nonfluent PPA syndromes (11 with progressive nonfluent aphasia, PNFA; five with progressive logopenic/phonological aphasia, LPA; three with progranulin-associated aphasia, GRN-PPA) compared with a group of healthy older controls. Voxel-based morphometry (VBM) was used to identify neuroanatomical associations of prosodic functions. Results Broadly comparable receptive prosodic deficits were exhibited by the PNFA, LPA and GRN-PPA subgroups, for acoustic, linguistic and affective dimensions of prosodic analysis. Discrimination of prosodic contours was significantly more impaired than discrimination of simple acoustic cues, and discrimination of intonation was significantly more impaired than discrimination of stress at phrasal level. Recognition of vocal emotions was more impaired than recognition of facial expressions for the PPA cohort, and recognition of certain emotions (in particular, disgust and fear) was relatively more impaired than others (sadness, surprise). VBM revealed atrophy associated with acoustic and linguistic prosody impairments in a distributed cortical network including areas likely to be involved in perceptual analysis of vocalisations (posterior temporal and inferior parietal cortices) and working memory (fronto-parietal circuitry). Grey matter associations of emotional prosody processing were identified for negative emotions (disgust, fear, sadness) in a broadly overlapping network of frontal, temporal, limbic and parietal areas. Conclusions Taken together, the findings show that receptive prosody is impaired in nonfluent PPA syndromes, and suggest a generic early perceptual deficit of prosodic signal

  16. Concern About Hunger May Increase Receptivity to GMOs.

    Science.gov (United States)

    Carter, B Elijah; Conn, Caitlin C; Wiles, Jason R

    2016-07-01

    Due to a phenomenon known as the 'backfire effect', intuition-based opinions can be inadvertently strengthened by evidence-based counterarguments. Students' views on genetically modified organisms (GMOs) may be subject to this effect. We explored the impact of an empathetically accessible topic, world hunger, on receptivity to GMO technology as an alternative to direct evidence-based approaches. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. The effects of receptive and expressive instructional sequences on varied conditional discriminations.

    Science.gov (United States)

    Bao, Shimin; Sweatt, Kristin T; Lechago, Sarah A; Antal, Sarah

    2017-10-01

    Many Early Intensive Behavioral Intervention (EIBI) curricula recommend teaching receptive responding before targeting expressive responding (Leaf & McEachin, 1999; Lovaas, 2003). However, a small literature base suggests that teaching expressive responses first may be more efficient when teaching children with ASD and other developmental disabilities (Petursdottir & Carr, 2011). The present study employed an alternating treatments design to compare the effects of three instructional sequences to teach feature, function, and class to three children diagnosed with ASD: (a) receptive-expressive, (b) expressive-receptive, and (c) mixed. The results suggested that expressive-receptive was the most efficient training sequence for all three participants. Additionally, greater emergent responding was observed with the expressive-receptive training sequence. © 2017 Society for the Experimental Analysis of Behavior.

  18. Magnetic field nanosensor based on Mn impurities

    Directory of Open Access Journals (Sweden)

    Daniela ENCIU

    2014-06-01

    Full Text Available Nanosensors based on graphene nanoribbon, studied in the present work, could provide a special interest in (aero space applications. More specifically, the paper proposes the construction of a nanosensor based on Mn (Manganese impurities. Different spin configurations of the Mn atoms are considered. The mathematical model used to determine the spin transport is based on Kohn-Sham equations. The spin-dependent transmission functions are calculated using the formalism of the nonequilibrium Green’s functions. The implementation of the mathematical model is performed in the SIESTA package. The spin transport properties are determined using the first principle calculations using density functional theory. The graphene nanoribbon with transition metal impurities is based on active element – the system of spins – which is influenced by the external perturbation field. Such nanostructures may serve as spatial applications. The differences between different excited states are determined and it is established that the energy range overlaps the mid-infrared wavelengths.

  19. Invocation Receptivity in Female of Rabbit

    Directory of Open Access Journals (Sweden)

    Martin Fik

    2017-05-01

    Full Text Available The target of this work was verified effect of transport females in the car for advance state of receptivity in young females broiler rabbits. We used nulliparous females of broiler hybrid HYCOLE (age 4-5 months, weight 3.5-3.8 kg. Experiment was realizated twice. First in half of November (31 females, second in half of February (32 females. Females was layed individually in boxes. After they were transported by car 1 hour (50 km. Before and after experiment we detected state of receptivity in females with coloration of vulva. The state of receptivity was determited from 1 for 4 colour of vulva. ( 1 – anemic coloration of vulva, 2- pink, 3 – red, 4- violet. We detected positive state of transport, on the receptivity. In November before transport was average of receptivity 1.87, after transport 2.25. The state of receptivity will be improve in 12 females (38.71 %. Improve from 1 to 2 was detected in 4 females, from 2 to 3 in 8 females. Improved from 2 to 4 , or from 3 to 4 wasn´t noticed in this group. The state of receptivity wasn´t changed in 19 females (61.29 %. In the state of receptivity 1 stayed 2 females, in the state 2 stayed 15 females, in the state 3 stayed 2 females and in the state 4 wasn´t any female. In February after the end of experiment, state of receptivity was improved with transport in the car from 2.19 to 2.65. The state of receptivity was improved in 13 females  (40.63 %.  Improve from 1 to 2 we detected in 1 female, from 2 to 3 we detected in 8 females, from 2 to 4 we detected in 2 females, from 3 to 4 in 2 females. In 19 females (59.38% we don´t noticed change state of receptivity. In the state of receptivity 1 were 2 females, in 2 were 11 females, in 3 were 5 females, in 4 was 1 female.

  20. Laboratory and field based evaluation of chromatography ...

    Science.gov (United States)

    The Monitor for AeRosols and GAses in ambient air (MARGA) is an on-line ion-chromatography-based instrument designed for speciation of the inorganic gas and aerosol ammonium-nitrate-sulfate system. Previous work to characterize the performance of the MARGA has been primarily based on field comparison to other measurement methods to evaluate accuracy. While such studies are useful, the underlying reasons for disagreement among methods are not always clear. This study examines aspects of MARGA accuracy and precision specifically related to automated chromatography analysis. Using laboratory standards, analytical accuracy, precision, and method detection limits derived from the MARGA chromatography software are compared to an alternative software package (Chromeleon, Thermo Scientific Dionex). Field measurements are used to further evaluate instrument performance, including the MARGA’s use of an internal LiBr standard to control accuracy. Using gas/aerosol ratios and aerosol neutralization state as a case study, the impact of chromatography on measurement error is assessed. The new generation of on-line chromatography-based gas and particle measurement systems have many advantages, including simultaneous analysis of multiple pollutants. The Monitor for Aerosols and Gases in Ambient Air (MARGA) is such an instrument that is used in North America, Europe, and Asia for atmospheric process studies as well as routine monitoring. While the instrument has been evaluat

  1. Deciphering the proteomic signature of human endometrial receptivity.

    Science.gov (United States)

    Garrido-Gómez, Tamara; Quiñonero, Alicia; Antúnez, Oreto; Díaz-Gimeno, Patricia; Bellver, Jose; Simón, Carlos; Domínguez, Francisco

    2014-09-01

    Are there any proteomic differences between receptive (R) and non-receptive (NR) endometrial receptivity array (ERA)-diagnosed endometria obtained on the same day of a hormonal replacement therapy (HRT) treatment cycle? There is a different proteomic signature between R and NR ERA-diagnosed endometrium obtained on the same day of HRT cycles. The human endometrial transcriptome has been extensively investigated in the last decade resulting in the development of a new diagnostic test based on the transcriptomic signature of the window of implantation (WOI). Much less is known about the proteomics derived from the transcripts present during the WOI. This study was a basic proteomic analysis of human endometrial biopsies taken from twelve IVF patients. Human endometrial biopsies were collected during HRT cycles after 5 days of progesterone (P) administration, and diagnosed as receptive (R; n = 6) or non-receptive (NR; n = 6) by the ERA test. Endometrial proteins were extracted, labelled and separated using differential in-gel electrophoresis (DIGE). Proteins were identified using mass spectrometry, followed up by in silico analysis. Validation studies using western blots and immunolocalization were performed for the progesterone receptor membrane component 1 (PGRMC1) and annexin A6 (ANXA6) proteins. DIGE analysis followed by protein identification by MALDI-MS and database searches revealed 24 differentially expressed proteins in R versus NR samples. In silico analysis showed two pathways which were significantly different between R and NR samples. Expression of PGRMC1 and ANXA6 was validated and localized by western blots and immunohistochemistry. These results highlight these proteins as key targets likely to be important in the comprehension of human endometrial receptivity. This was mainly a descriptive study with no functional studies on the proteins found. We also used a low number of human endometrial samples for the DIGE analysis. This study identified the

  2. Blue-light reception through quaternary transitions

    National Research Council Canada - National Science Library

    Christopher Engelhard; Ralph P Diensthuber; Andreas Möglich; Robert Bittl

    2017-01-01

    .... Using electron-electron double resonance (ELDOR) spectroscopy and site-directed spin labelling, we chart the structural transitions facilitating blue-light reception in the engineered light-oxygen-voltage (LOV...

  3. Stigmatic receptivity determines the seed set in Indian mustard, rice and wheat crops.

    Science.gov (United States)

    Gupta, Ramwant; Sutradhar, Hrishikesh; Chakrabarty, S K; Ansari, Mohhammed Wahid; Singh, Yogendra

    2015-01-01

    Stigmatic receptivity restricts the successful pollination in cereal crops. The present study deals with the biochemical test for enzymes producing in stigma of field crops such as Indian mustard, rice and wheat. The alcohol dehydrogenase and hydrogen peroxide assays revealed stigmatic receptivity as a violet color and oxygen bubbles released by the chemical reaction. Therefore, the 2 quick tests are in conformity to each other and supported the seed set data, which was utmost at blooming stage of flower ranged between 2-4 d All the 3 crops showed variation in stigmatic receptivity with respect to different time periods of blooming stages and hence, it may affects simultaneous pollen germination and tube growth, fertilization and seed set. The present finding suggests that the growth of pollen tube and stigma receptivity could be influenced by specific enzymes on stigma surface after 2-4 d of blooming stage, which contributes to proper seed set.

  4. A notch-wire composite antenna for polarization diversity reception

    OpenAIRE

    Kuga, Nobuhiro; Arai, H; Goto, N

    1998-01-01

    This paper presents a notch-wire composite antenna for polarization diversity reception in an indoor base-station system, A three-notched disk antenna and a wire antenna are proposed as component antennas for the horizontal and the vertical polarization, respectively. These component antennas are unified as a single composite diversity antenna by mounting the wire antenna on the notched disk. Antenna characteristics are calculated using the method of moments (MoM) with wire grid models and ex...

  5. KSC ADVANCED GROUND BASED FIELD MILL V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Ground Based Field Mill (AGBFM) network consists of 34 (31 operational) field mills located at Kennedy Space Center (KSC), Florida. The field mills...

  6. Receptivity of a precessing vortex core to open-loop forcing in a swirling jet and its predictability by linear stability adjoint theory

    Science.gov (United States)

    Müller, Jens; Lückoff, Finn; Oberleithner, Kilian

    2017-11-01

    The precessing vortex core (PVC) is a dominant coherent structure which occurs in swirling jets such as in swirl-stabilised gas turbine combustors. It stems from a global hydrodynamic instability caused by an internal feedback mechanism within the jet core. In this work, open-loop forcing is applied to a generic non-reacting swirling jet to investigate its receptivity to external actuation regarding lock-in behaviour of the PVC for different streamwise positions and Reynolds numbers. The forcing is periodically exerted by zero net mass flux synthetic jets which are introduced radially through slits inside the duct walls upstream of the swirling jet's exit plane. Time-resolved pressure measurements are conducted to identify the PVC frequency and stereo PIV combined with proper orthogonal decomposition in the duct and free field is used to extract the mean flow and the PVC mode. The data is used in a global linear stability framework to gain the adjoint of the PVC which reveals the regions of highest receptivity to periodic forcing based on mean flow input only. This theoretical receptivity model is compared with the experimentally obtained receptivity results and the validity and applicability of the adjoint model for the prediction of optimal forcing positions is discussed.

  7. DC-based magnetic field controller

    Science.gov (United States)

    Kotter, D.K.; Rankin, R.A.; Morgan, J.P.

    1994-05-31

    A magnetic field controller is described for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a Hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage. 1 fig.

  8. DC-based magnetic field controller

    Science.gov (United States)

    Kotter, Dale K.; Rankin, Richard A.; Morgan, John P,.

    1994-01-01

    A magnetic field controller for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage.

  9. [Siebold and Ishizaka Sotetsu's contribution to the reception of acupuncture in nineteenth century Europe: a comparative research based on the acupuncture manuscripts in the Siebold collection].

    Science.gov (United States)

    Mathias, Vigouroux; Machi, Senjuro

    2011-09-01

    This article examines Siebold and his relations with the Tokugawa shogunate acupuncture doctor Ishizaka Sotetsu, based on both Western and Japanese primary sources. It is well known that Siebold's contribution to a better understanding of Oriental medicine in Europe was limited to his interest in Japanese acupuncture, particularly Ishizaka Sotetsu's acupuncture. However, past research on this subject has only relied either on documents written in Dutch by Siebold's disciples or on Ishizaka Sotetsu's writings on acupuncture, therefore making it impossible to match the Dutch translations with the original Japanese manuscripts. This article brings new insights in Siebold's study on Ishizaka's acupuncture, investigating from a comparative point of view documents held by Leiden University, Leiden National Museum of Ethnology, Ruhr-Universittät Bochum, Toyo Bunko Library and the Ishizaka family's collection. The second part of the article analyzes also how Siebold's interest in Ishizaka Sotetsu's acupuncture differs from Rhyne's and Kaempfer's interest in Japanese acupuncture

  10. The relationship between receptive and productive vocabulary of Slavic EFL learners

    Directory of Open Access Journals (Sweden)

    Šišková Zdislava

    2016-12-01

    Full Text Available This study investigates the relationship between learners’ receptive vocabulary knowledge as measured by the Vocabulary Size Test (Nation and Beglar, 2007 and free productive vocabulary knowledge as demonstrated by the learners when writing a short story based on pictures. The focus is on three different areas of productive vocabulary use: lexical diversity (i.e. the proportion of different words in a text, lexical sophistication (i.e. the proportion of advanced words in a text and lexical density (i.e. the proportion of content words in a text. The results of a bivariate correlation analysis indicate that there is a moderate relationship between learners’ receptive vocabulary knowledge and lexical diversity of the texts they produce; there is a weak relationship between their receptive vocabulary knowledge and lexical sophistication in the texts; and there is no relationship between their receptive vocabulary knowledge and lexical density.

  11. Modelling of induced electric fields based on incompletely known magnetic fields

    Science.gov (United States)

    Laakso, Ilkka; De Santis, Valerio; Cruciani, Silvano; Campi, Tommaso; Feliziani, Mauro

    2017-08-01

    Determining the induced electric fields in the human body is a fundamental problem in bioelectromagnetics that is important for both evaluation of safety of electromagnetic fields and medical applications. However, existing techniques for numerical modelling of induced electric fields require detailed information about the sources of the magnetic field, which may be unknown or difficult to model in realistic scenarios. Here, we show how induced electric fields can accurately be determined in the case where the magnetic fields are known only approximately, e.g. based on field measurements. The robustness of our approach is shown in numerical simulations for both idealized and realistic scenarios featuring a personalized MRI-based head model. The approach allows for modelling of the induced electric fields in biological bodies directly based on real-world magnetic field measurements.

  12. Effects of Nose Radius and Aerodynamic Loading on Leading Edge Receptivity

    Science.gov (United States)

    Hammerton, P. W.; Kerschen, E. J.

    1998-01-01

    An analysis is presented of the effects of airfoil thickness and mean aerodynamic loading on boundary-layer receptivity in the leading-edge region. The case of acoustic free-stream disturbances, incident on a thin cambered airfoil with a parabolic leading edge in a low Mach number flow, is considered. An asymptotic analysis based on large Reynolds number is developed, supplemented by numerical results. The airfoil thickness distribution enters the theory through a Strouhal number based on the nose radius of the airfoil, S = (omega)tau(sub n)/U, where omega is the frequency of the acoustic wave and U is the mean flow speed. The influence of mean aerodynamic loading enters through an effective angle-of-attack parameter ti, related to flow around the leading edge from the lower surface to the upper. The variation of the receptivity level is analyzed as a function of S, mu, and characteristics of the free-stream acoustic wave. For an unloaded leading edge, a finite nose radius dramatically reduces the receptivity level compared to that for a flat plate, the amplitude of the instability waves in the boundary layer being decreased by an order of magnitude when S = 0.3. Modest levels of aerodynamic loading are found to further decrease the receptivity level for the upper surface of the airfoil, while an increase in receptivity level occurs for the lower surface. For larger angles of attack close to the critical angle for boundary layer separation, a local rise in the receptivity level occurs for the upper surface, while for the lower surface the receptivity decreases. The effects of aerodynamic loading are more pronounced at larger values of S. Oblique acoustic waves produce much higher receptivity levels than acoustic waves propagating downstream parallel to the airfoil chord.

  13. The politics, science, and art of receptivity

    Directory of Open Access Journals (Sweden)

    Emily Beausoleil

    2014-03-01

    Full Text Available With so much attention on the issue of voice in democratic theory, the inverse question of how people come to listen remains a marginal one. Recent scholarship in affect and neuroscience reveals that cognitive and verbal strategies, while privileged in democratic politics, are often insufficient to cultivate the receptivity that constitutes the most basic premise of democratic encounters. This article draws on this scholarship and a recent case of forum theatre to examine the conditions of receptivity and responsiveness, and identify specific strategies that foster such conditions. It argues that the forms of encounter most effective in cultivating receptivity are those that move us via affective intensity within pointedly mediated contexts. It is this constellation of strategies—this strange marriage of immersion and mediation—that enabled this performance to surface latent memory, affect and bias, unsettle entrenched patterns of thought and behaviour, and provide the conditions for revisability. This case makes clear that to lie beyond the domain of cognitive and verbal processes is not to lie beyond potential intervention, and offers insight to how such receptivity might be achieved in political processes more broadly.

  14. Measuring receptive collocational competence across proficiency ...

    African Journals Online (AJOL)

    Kate H

    extent to which receptive knowledge of collocations of EFL learners varies across word frequency bands. ..... language through in-class reading and conversation tasks which totalled 75 hours. The .... 4 Readers are referred to Wray (2002) and Barfield and Gyllstad (2009) for more details on how to teach collocations.

  15. The reception of relativity in the Netherlands

    NARCIS (Netherlands)

    van Besouw, J.; van Dongen, J.; Maas, A.; Schatz, H.

    2013-01-01

    This article reviews the early academic and public reception of Albert Einstein's theory of relativity in the Netherlands, particularly after Arthur Eddington's eclipse experiments of 1919. Initially, not much attention was given to relativity, as it did not seem an improvement over Hendrik A.

  16. Measuring receptive collocational competence across proficiency levels

    Directory of Open Access Journals (Sweden)

    Déogratias Nizonkiza

    2015-12-01

    Full Text Available The present study investigates, (i English as Foreign Language (EFL learners’ receptive collocational knowledge growth in relation to their linguistic proficiency level; (ii how much receptive collocational knowledge is acquired as proficiency develops; and (iii the extent to which receptive knowledge of collocations of EFL learners varies across word frequency bands. A proficiency measure and a collocation test were administered to English majors at the University of Burundi. Results of the study suggest that receptive collocational competence develops alongside EFL learners’ linguistic proficiency; which lends empirical support to Gyllstad (2007, 2009 and Author (2011 among others, who reported similar findings. Furthermore, EFL learners’ collocations growth seems to be quantifiable wherein both linguistic proficiency level and word frequency occupy a crucial role. While more gains in terms of collocations that EFL learners could potentially add as a result of change in proficiency are found at lower levels of proficiency; collocations of words from more frequent word bands seem to be mastered first, and more gains are found at more frequent word bands. These results confirm earlier findings on the non-linearity nature of vocabulary growth (cf. Meara 1996 and the fundamental role played by frequency in word knowledge for vocabulary in general (Nation 1983, 1990, Nation and Beglar 2007, which are extended here to collocations knowledge.

  17. Receptivity to television fast-food restaurant marketing and obesity among U.S. youth.

    Science.gov (United States)

    McClure, Auden C; Tanski, Susanne E; Gilbert-Diamond, Diane; Adachi-Mejia, Anna M; Li, Zhigang; Li, Zhongze; Sargent, James D

    2013-11-01

    Advertisement of fast food on TV may contribute to youth obesity. The goal of the study was to use cued recall to determine whether TV fast-food advertising is associated with youth obesity. A national sample of 2541 U.S. youth, aged 15-23 years, were surveyed in 2010-2011; data were analyzed in 2012. Respondents viewed a random subset of 20 advertisement frames (with brand names removed) selected from national TV fast-food restaurant advertisements (n=535) aired in the previous year. Respondents were asked if they had seen the advertisement, if they liked it, and if they could name the brand. A TV fast-food advertising receptivity score (a measure of exposure and response) was assigned; a 1-point increase was equivalent to affirmative responses to all three queries for two separate advertisements. Adjusted odds of obesity (based on self-reported height and weight), given higher TV fast-food advertising receptivity, are reported. The prevalence of overweight and obesity, weighted to the U.S. population, was 20% and 16%, respectively. Obesity, sugar-sweetened beverage consumption, fast-food restaurant visit frequency, weekday TV time, and TV alcohol advertising receptivity were associated with higher TV fast-food advertising receptivity (median=3.3 [interquartile range: 2.2-4.2]). Only household income, TV time, and TV fast-food advertising receptivity retained multivariate associations with obesity. For every 1-point increase in TV fast-food advertising receptivity score, the odds of obesity increased by 19% (OR=1.19, 95% CI=1.01, 1.40). There was no association between receptivity to televised alcohol advertisements or fast-food restaurant visit frequency and obesity. Using a cued-recall assessment, TV fast-food advertising receptivity was found to be associated with youth obesity. © 2013 American Journal of Preventive Medicine.

  18. Ocean Wave Simulation Based on Wind Field.

    Science.gov (United States)

    Li, Zhongyi; Wang, Hao

    2016-01-01

    Ocean wave simulation has a wide range of applications in movies, video games and training systems. Wind force is the main energy resource for generating ocean waves, which are the result of the interaction between wind and the ocean surface. While numerous methods to handle simulating oceans and other fluid phenomena have undergone rapid development during the past years in the field of computer graphic, few of them consider to construct ocean surface height field from the perspective of wind force driving ocean waves. We introduce wind force to the construction of the ocean surface height field through applying wind field data and wind-driven wave particles. Continual and realistic ocean waves result from the overlap of wind-driven wave particles, and a strategy was proposed to control these discrete wave particles and simulate an endless ocean surface. The results showed that the new method is capable of obtaining a realistic ocean scene under the influence of wind fields at real time rates.

  19. An alternative representation of the receptance: The 'elliptical plane' and its modal properties

    Science.gov (United States)

    Montalvão, Diogo; Amafabia, Daerefa-a. Mitsheal

    2018-03-01

    Modal Identification from Frequency Response Functions (FRFs) has been extensively investigated up to the point its research reached a stagnation state. Yet, a new approach to determine the modal damping factors from FRFs was recently proposed, showing that there still is scope for new findings in the field. Contrary to other modal identification methods which are based on the dynamic motion governing equations, the method used the dissipated energy per cycle of vibration as a starting point. For lightly damped systems with conveniently spaced modes, it produced quite accurate results, especially when compared to the well-known method of the inverse. The method used a plot of the sine of the phase of the receptance against its amplitude, whereby damping was determined from the slope of a linear fit to the resulting plot. In this paper, it is shown that this plot has other (perhaps more important) special properties that were not explored before. Near resonant frequencies, its shape is elliptical, whereby the real and imaginary parts of the modal constants can be determined from numerical curve-fitting. This finding allowed developing a new method which formulation is presented in this paper. The method is discussed through numerical and experimental examples. Although the intention is not to present a new modal identification method that is superior to other existing ones (like the method of the inverse or those based on the Nyquist plot), the authors believe that this new representation of the receptance and its properties may bring valuable insights for other researchers in the field.

  20. Receptive and Productive Vocabulary Sizes of L2 Learners

    Science.gov (United States)

    Webb, Stuart

    2008-01-01

    This study investigated the relationship between receptive and productive vocabulary size. The experimental design expanded upon earlier methodologies by using equivalent receptive and productive test formats with different receptive and productive target words to provide more accurate results. Translation tests were scored at two levels of…

  1. Radiation Emergency Preparedness Tools: Virtual Community Reception Center

    Centers for Disease Control (CDC) Podcasts

    2011-02-28

    This podcast is an overview of resources from the Clinician Outreach and Communication Activity (COCA) Call: Practical Tools for Radiation Emergency Preparedness. A specialist working with CDC's Radiation Studies Branch describes a web-based training tool known as a Virtual Community Reception Center (vCRC).  Created: 2/28/2011 by National Center for Environmental Health (NCEH) Radiation Studies Branch and Emergency Risk Communication Branch (ERCB)/Joint Information Center (JIC); Office of Public Health Preparedness and Response (OPHPR).   Date Released: 2/28/2011.

  2. Mobile television news: a study on the reception of the news on the mobile audience by adults / seniors

    Directory of Open Access Journals (Sweden)

    Cristiane Finger Costa

    2015-08-01

    Full Text Available By inserting digital television in Brazil, the programming of open television becomes available in mobile and portable devices without any additional fares. The reception of contents anytime and anywhere is bound to provoke change in the relation between journalists and viewers. For this work, a survey was made in the field of reception to identify, in a qualitative way, the expectations and needs of senior/adult public when watching news in cell phones.

  3. The networked reception of transmedial universes

    DEFF Research Database (Denmark)

    Tosca, Susana; Klastrup, Lisbeth

    2016-01-01

    qualitative and quantitative studies. We argue that mapping user experience requires a sophisticated and holistic analytical approach - particularly, due to the popularity of social media platforms. We conclude the article by developing the concept of "networked reception" to characterize new kinds...... of transmedial world experience afforded by social media, which allow users to distribute and communicate not only the content of media texts but also their own experience and reception of transmedial world “texts”.......Building upon ten years of empirical work, this paper reflects on how to study increasingly complex user engagement with transmedial worlds. We examine our own analytical evolution from an initial aesthetic orientation to our current effort to incorporate the user´s own perspective through...

  4. Healthy viewing: the reception of medical narratives.

    Science.gov (United States)

    Davin, Solange

    2003-09-01

    This paper draws on two reception studies. One focuses on an American medical drama which respondents perceived as entertainment but also as a reliable source of information from which they collected medical and social data by using emotional and ludic strategies. The second compares parallel illness narratives in a soap opera and a documentary. Soap operas were described by informants as good pedagogic tools because they attracted large audiences and promoted identification and repetition which enhance learning. On the other hand, they criticised the documentary for being incomplete and artificial. The conclusion argues that viewers are media-literate, astute and insightful. They produce sophisticated, subtle interpretations which cannot be predicted by content analyses of programmes alone. More reception research is therefore needed, particularly since television is increasingly omnipresent and provides a considerable portion of the public's medical knowledge.

  5. [The development of a computer-based visual field analyzer].

    Science.gov (United States)

    Yang, D; Hou, W; Peng, C; Mou, Y

    2000-09-01

    Visual field is one of the important visual functions; it is the extent of the visual field defect that can be employed in judging whether the visual function is impaired. The rapid achievements in computer technologies do provide an impulse for improvement of visual field detection, making possible the automatic, rapid, accurate, detailed and large-scaled visual field detection. This paper gives a thorough description about development of the visual field analyzer, model TEC-2A, which is based on PC windows platform, Visual Basic software developing tool, ISA peripheral circuits, standard Goldmann visual field half-ball and standard stimulus.

  6. Online Movie Trailers - A Reception Analysis

    OpenAIRE

    Jensen, Frida Videbæk; Rozé, Caroline

    2014-01-01

    This project is a reception analysis of how a target group receive online movie trailers. It utilized a focus group as means of research with participants from the dormitories Kollibrien and Korallen. We concluded that the group we investigated were not interested in online movie trailers as anything else than a preview of a movie. They preferred to experience movie trailers in the cinema. Their opinion of specific movie trailers were also determined by whether or not they identified with the...

  7. Czech children's literature reception in Slovenia

    OpenAIRE

    Starc, Barbara

    2016-01-01

    This master’s degree thesis introduces the historical background of the Czech nation and the cultural contacts between Slovenes and Czechs. It outlines the development of the Czech young adult literature. In the thesis is qualitatively and quantitatively researched the reception of the Czech young adult literature. With a qualitative research it has been discovered how many young adult books have been translated from Czech into Slovene language, how many in different periods and which lit...

  8. Non-visual reception in sculpture

    OpenAIRE

    Lautar, Anja

    2013-01-01

    In my thesis I explore the potential of non-visual components of sculptural artworks. For that purpose I define reception and perception. I introduce senses and sculptural artworks of 20th century that address the specific sense. I examine reasons and consequences of favored treatment of vision and neglection of other senses, as well as the situation of people with blindness and visual impairement in today's visual culture. I committed my own artistic expression to create sculptural artwor...

  9. The Critical Reception of Lewis Nordan

    DEFF Research Database (Denmark)

    Bjerre, Thomas Ærvold

    2010-01-01

    The essay covers the critical reception of Mississippi-writer Lewis Nordan from his debut in 1983 to the boost in scholarly attention in the new millennium. The essay covers newspaper reviews but pays particular attention to the many academic essays that have placed Nordan as a writer...... in the southern literary tradition and have highlighted themes such as magical realism, the grotesque, race relations, music, and gender....

  10. Charging for port reception facilities in North Sea ports: putting theory into practice.

    Science.gov (United States)

    Carpenter, A; Macgill, S

    2001-04-01

    The aim of this paper is to evaluate the charging systems for the use of port reception facilities for waste oil, and to examine the potential impact of the charging elements of the new (late 2000) EU Directive on port reception facilities for ship-generated waste and cargo residues. Experience to date with alternative models for charging is considered. Conclusions are drawn about the effectiveness of the EU Directive as a means of controlling pollution in the North Sea and producing a 'level playing field' between ports.

  11. Receptive vocabulary analysis in Down syndrome.

    Science.gov (United States)

    Loveall, Susan J; Channell, Marie Moore; Phillips, B Allyson; Abbeduto, Leonard; Conners, Frances A

    2016-08-01

    The present study is an in-depth examination of receptive vocabulary in individuals with Down syndrome (DS) in comparison to control groups of individuals of similar nonverbal ability with typical development (TD) and non-specific etiology intellectual disability (ID). Verb knowledge was of particular interest, as it is known to be a predictor of later syntactic development. Fifty participants with DS, aged 10-21 years, 29 participants with ID, 10-21 years, and 29 participants with TD, 4-9 years, completed measures of receptive vocabulary (PPVT-4), nonverbal ability (Leiter-R), and phonological memory (Nonword Repetition subtest of the CTOPP). Groups were compared on percentage correct of noun, verb and attribute items on the PPVT-4. Results revealed that on verb items, the participants with ID performed significantly better than both participants with DS and TD, even when overall receptive vocabulary ability and phonological memory were held constant. Groups with DS and TD showed the same pattern of lexical knowledge, performing better on nouns than both verbs and attributes. In contrast, the group with ID performed similarly on nouns and verbs, but worse on attributes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Structural modification. Part 1: rotational receptances

    Science.gov (United States)

    Mottershead, John E.; Kyprianou, Andreas; Ouyang, Huajiang

    2005-06-01

    The inverse problem of assigning natural frequencies and antiresonances by a modification to the stiffness, mass and damping of a structure is addressed. Very simple modifications such as the addition of masses and grounded springs can be easily accommodated and require the measurement of translational receptances at the connection coordinates. Realistic modifications of practical usefulness, such as a modification by an added beam, require the measurement of rotational as well as translational receptances. Such data are difficult to obtain because of the practical problems of applying a pure moment. One method, the so-called 'T-block' approach, has received considerable attention in the literature, but the accompanying problem of ill-conditioning has not been fully addressed until now. The T-block is attached to the structure at the modification point, so that a force applied to the T-block generates a moment together with a force at the connection point between the T-block and the parent structure. Forces and linear displacements measured on the T-block, together with a mass and stiffness model of the T-block itself, allow the problem to be cast as a special case of excitation by multiple inputs. The resulting equations are generally ill-conditioned, but can be regularized by using a small number of independent measurements. The methodology and signal processing techniques required to estimate the rotational receptances are described. An experimental example is used to demonstrate the practical application of the method.

  13. Geothermal emissions data base, Wairakei geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, S.R. (comp.)

    1978-04-01

    A database subset on the gaseous emissions from the Wairakei geothermal field is presented. Properties and states of the reservoir fluid such as flow rates, wellhead pressure, and enthalpy are included in the file along with the well name and constituent measurement. This subset is the result of an initial screening of the data covering 1965 to 1971, and new additions will be appended periodically to the file. The data is accessed by a database management system as are all other subsets in the file. Thereby, one may search the database for specific data requirements and print selective output. For example, one may wish to locate reservoir conditions for cases only when the level of the constituent exceeded a designated value. Data output is available in the form of numerical compilations such as the attached, or graphical displays disposed to paper, film or magnetic tape.

  14. Characterization of the Transcriptional Complexity of the Receptive and Pre-receptive Endometria of Dairy Goats.

    Science.gov (United States)

    Zhang, Lei; An, Xiao-Peng; Liu, Xiao-Rui; Fu, Ming-Zhe; Han, Peng; Peng, Jia-Yin; Hou, Jing-Xing; Zhou, Zhan-Qin; Cao, Bin-Yun; Song, Yu-Xuan

    2015-09-16

    Endometrium receptivity is essential for successful embryo implantation in mammals. However, the lack of genetic information remains an obstacle to understanding the mechanisms underlying the development of a receptive endometrium from the pre-receptive phase in dairy goats. In this study, more than 4 billion high-quality reads were generated and de novo assembled into 102,441 unigenes; these unigenes were annotated using published databases. A total of 3,255 unigenes that were differentially expressed (DEGs) between the PE and RE were discovered in this study (P-values < 0.05). In addition, 76,729-77,102 putative SNPs and 12,837 SSRs were discovered in this study. Bioinformatics analysis of the DEGs revealed a number of biological processes and pathways that are potentially involved in the establishment of the RE, notably including the GO terms proteolysis, apoptosis, and cell adhesion and the KEGG pathways Cell cycle and extracellular matrix (ECM)-receptor interaction. We speculated that ADCY8, VCAN, SPOCK1, THBS1, and THBS2 may play important roles in the development of endometrial receptivity. The de novo assembly provided a good starting point and will serve as a valuable resource for further investigations into endometrium receptivity in dairy goats and future studies on the genomes of goats and other related mammals.

  15. Radiofrequency fields: Bases for exposure limits

    Energy Technology Data Exchange (ETDEWEB)

    Paolo Vecchia [Department of Technologies and Health National Institute of Health, Rome (Italy)

    2006-07-01

    Several biological effects have been reported at exposure levels below the threshold for thermal effects, but most of them require independent confirmation before being accepted as established. However, no seems to have relevant implications for human health. Precautionary measures should be based on a cost/benefit analysis, and be proportionate on one side to the risk they aim at preventing and on the other side to actions taken in other areas to prevent comparable risks. (N.C.)

  16. Design of signal reception and processing system of embedded ultrasonic endoscope

    Science.gov (United States)

    Li, Ming; Yu, Feng; Zhang, Ruiqiang; Li, Yan; Chen, Xiaodong; Yu, Daoyin

    2009-11-01

    Embedded Ultrasonic Endoscope, based on embedded microprocessor and embedded real-time operating system, sends a micro ultrasonic probe into coelom through the biopsy channel of the Electronic Endoscope to get the fault histology features of digestive organs by rotary scanning, and acquires the pictures of the alimentary canal mucosal surface. At the same time, ultrasonic signals are processed by signal reception and processing system, forming images of the full histology of the digestive organs. Signal Reception and Processing System is an important component of Embedded Ultrasonic Endoscope. However, the traditional design, using multi-level amplifiers and special digital processing circuits to implement signal reception and processing, is no longer satisfying the standards of high-performance, miniaturization and low power requirements that embedded system requires, and as a result of the high noise that multi-level amplifier brought, the extraction of small signal becomes hard. Therefore, this paper presents a method of signal reception and processing based on double variable gain amplifier and FPGA, increasing the flexibility and dynamic range of the Signal Reception and Processing System, improving system noise level, and reducing power consumption. Finally, we set up the embedded experiment system, using a transducer with the center frequency of 8MHz to scan membrane samples, and display the image of ultrasonic echo reflected by each layer of membrane, with a frame rate of 5Hz, verifying the correctness of the system.

  17. Receptivity to Kinetic Fluctuations: A Multiple Scales Approach

    Science.gov (United States)

    Edwards, Luke; Tumin, Anatoli

    2017-11-01

    The receptivity of high-speed compressible boundary layers to kinetic fluctuations (KF) is considered within the framework of fluctuating hydrodynamics. The formulation is based on the idea that KF-induced dissipative fluxes may lead to the generation of unstable modes in the boundary layer. Fedorov and Tumin solved the receptivity problem using an asymptotic matching approach which utilized a resonant inner solution in the vicinity of the generation point of the second Mack mode. Here we take a slightly more general approach based on a multiple scales WKB ansatz which requires fewer assumptions about the behavior of the stability spectrum. The approach is modeled after the one taken by Luchini to study low speed incompressible boundary layers over a swept wing. The new framework is used to study examples of high-enthalpy, flat plate boundary layers whose spectra exhibit nuanced behavior near the generation point, such as first mode instabilities and near-neutral evolution over moderate length scales. The configurations considered exhibit supersonic unstable second Mack modes despite the temperature ratio Tw /Te > 1 , contrary to prior expectations. Supported by AFOSR and ONR.

  18. Feasibility of field-based light scattering spectroscopy

    Science.gov (United States)

    Yang, Changhuei; Perelman, Lev T.; Wax, Adam; Dasari, Ramachandra R.; Feld, Michael S.

    2000-04-01

    Light scattering spectroscopy (LSS) is a new technique capable of accurately measuring the features of nuclei and other cellular organelles in situ. We present the considerations required to implement and interpret field- based detection in LSS, where the scattered electric field is detected interferometrically, and demonstrate that the technique is experimentally feasible. A theoretical formalism for modeling field-based LSS signals based on Mie scattering is presented. Phase-front uniformity is shown to play an important and novel role. Results of heterodyne experiments with polystyrene microspheres that localize LSS signals to a region about 30 micrometers in axial extent are reported. In addition, differences between field-based LSS and the earlier intensity-based LSS are discussed.

  19. Building Harmony through Religious Reception in Culture: Lesson Learned from Radin Jambat Folktale of Lampung

    Directory of Open Access Journals (Sweden)

    Agus Iswanto

    2018-12-01

    Full Text Available Understanding of the existence of various religious receptions in culture gives a great opportunity for the building and nurturance of harmony among religious followers and for the creating of solidarities in the society. This article uncovers receptions of religious aspects (ultimate truth aspect/god, cosmological aspect and religious ritual aspect in the cultural products of Radin Lambat, a folktale from Lampung. The article is based on the texts of Radin Lambat folktale, interviews, and other literary sources about Lampung cultures. Religious receptions as shown in Radin Lambat folktale indicate the preservation of past beliefs, coupled with the gentle addition and inclusion of Islamic teachings, to create harmonization between religion and tradition through folktale. This shows that Islam in the societies of Lampung is Islam that values cultures through the processes of gradual and varied receptions. This article is expected to add evidence to related sources about the concepts and practices of harmony among religious followers in Indonesia in local tradition, and the addition to the range of the rare religious-cultural reception studies of Lampung society

  20. Does metacognitive strategy instruction improve impaired receptive cognitive-communication skills following acquired brain injury?

    Science.gov (United States)

    Copley, Anna; Smith, Kathleen; Savill, Katelyn; Finch, Emma

    2015-01-01

    To investigate if metacognitive strategy instruction (MSI) improves the receptive language skills of adults with cognitive-communication disorders secondary to acquired brain injury (ABI). An ABA intervention programme was implemented with eight adults with ABI, aged 25-70 years. The Measure of Cognitive-Linguistic Abilities (MCLA) was administered at baseline and following treatment. The treatment employed in this study involved three components: individual goal-based therapy, group remediation therapy using self-instruction and home practice. No receptive language sub-tests of the MCLA reached statistical significance. However, participants' raw score improvements in receptive language sub-tests indicated that MSI may be effective at remediating CCDs following ABI. Preliminary findings indicate that MSI may be effective in improving receptive language skills in adults with CCDs following ABI. Further research involving a more rigorous study, a larger sample size and a more reliable outcome measure is necessary and may provide statistically significant evidence for the effectiveness of MSI for remediating receptive language disorders.

  1. Near-Field Nanolasers based on Nonradiating Anapole Modes

    KAUST Repository

    Gongora, J. S. Totero

    2016-05-31

    By employing ab-initio simulations of Maxwell-Bloch equations with a source of quantum noise, we study a new laser concept based on photonic dark-matter nanostructures that emit only in the near-field, with no far-field radiation pattern.

  2. Graphene-based field-effect transistor biosensors

    Science.gov (United States)

    Chen; , Junhong; Mao, Shun; Lu, Ganhua

    2017-06-14

    The disclosure provides a field-effect transistor (FET)-based biosensor and uses thereof. In particular, to FET-based biosensors using thermally reduced graphene-based sheets as a conducting channel decorated with nanoparticle-biomolecule conjugates. The present disclosure also relates to FET-based biosensors using metal nitride/graphene hybrid sheets. The disclosure provides a method for detecting a target biomolecule in a sample using the FET-based biosensor described herein.

  3. Extension of Flutter Boundaries Using In-Flight Receptance Data

    Science.gov (United States)

    2012-11-01

    in a wind-tunnel aerofoil rig. The aerofoil and its suspension were designed as part of the project. The advantage of the receptance method over...binary flutter in a wind-tunnel aerofoil rig. The aerofoil and its suspension were designed as part of the project. The advantage of the receptance...and determination of control gains. This report describes the theory of the method of receptances and its implementation on a wind- tunnel aerofoil

  4. Feedback linearisation of nonlinear vibration problems: A new formulation by the method of receptances

    Science.gov (United States)

    Zhen, Chong; Jiffri, Shakir; Li, Daochun; Xiang, Jinwu; Mottershead, John E.

    2018-01-01

    New output feedback-linearisation theory is presented for the treatment of nonlinear vibration problems by a receptance-based approach. An important aspect is a new formulation for investigating the stability of the zero dynamics. The overall methodology possesses the usual benefits of the receptance method, namely that the system matrices (with associated assumptions and approximations) do not have to be known. In addition, it has the distinction of not requiring the form and parameter values of the nonlinearity when the input and output degrees of freedom are away from the nonlinearity itself. This represents a valuable advance over the conventional time-domain feedback linearisation approach.

  5. Cold cathode rf guns based study on field emission

    Directory of Open Access Journals (Sweden)

    Xiangkun Li

    2013-12-01

    Full Text Available Recently cold cathodes based on field emission have drawn attention and been considered to drive accelerators and free electron lasers, due to the progress in field emitter arrays and planar emitters like diamond films. In this paper, we reviewed the characteristics of field emission in rf fields. Simulations of S-band rf guns consisting of a cathode cell and a full cell were done. We showed that a shorter cathode cell with a length of 0.25–0.3 of λ/2 is in favor of obtaining both low emittance and low energy spread bunches when the amplitude of electric field on the cathode surface ranges from 60 to 80  MV/m. A single cell test cavity has been installed to study field emission of diamond films and the measured beam current showed a good agreement with theoretical calculations.

  6. Anisotropy in wavelet-based phase field models

    KAUST Repository

    Korzec, Maciek

    2016-04-01

    When describing the anisotropic evolution of microstructures in solids using phase-field models, the anisotropy of the crystalline phases is usually introduced into the interfacial energy by directional dependencies of the gradient energy coefficients. We consider an alternative approach based on a wavelet analogue of the Laplace operator that is intrinsically anisotropic and linear. The paper focuses on the classical coupled temperature/Ginzburg--Landau type phase-field model for dendritic growth. For the model based on the wavelet analogue, existence, uniqueness and continuous dependence on initial data are proved for weak solutions. Numerical studies of the wavelet based phase-field model show dendritic growth similar to the results obtained for classical phase-field models.

  7. Airborne Antenna System for Minimum-Cycle-Slip GPS Reception

    Science.gov (United States)

    Wright, C. Wayne

    2009-01-01

    A system that includes a Global Positioning System (GPS) antenna and associated apparatus for keeping the antenna aimed upward has been developed for use aboard a remote-sensing-survey airplane. The purpose served by the system is to enable minimum- cycle-slip reception of GPS signals used in precise computation of the trajectory of the airplane, without having to restrict the airplane to maneuvers that increase the flight time needed to perform a survey. Cycle slip signifies loss of continuous track of the phase of a signal. Minimum-cycle-slip reception is desirable because maintaining constant track of the phase of the carrier signal from each available GPS satellite is necessary for surveying to centimeter or subcentimeter precision. Even a loss of signal for as short a time as a nanosecond can cause cycle slip. Cycle slips degrade the quality and precision of survey data acquired during a flight. The two principal causes of cycle slip are weakness of signals and multipath propagation. Heretofore, it has been standard practice to mount a GPS antenna rigidly on top of an airplane, and the radiation pattern of the antenna is typically hemispherical, so that all GPS satellites above the horizon are viewed by the antenna during level flight. When the airplane must be banked for a turn or other maneuver, the reception hemisphere becomes correspondingly tilted; hence, the antenna no longer views satellites that may still be above the Earth horizon but are now below the equatorial plane of the tilted reception hemisphere. Moreover, part of the reception hemisphere (typically, on the inside of a turn) becomes pointed toward ground, with a consequent increase in received noise and, therefore, degradation of GPS measurements. To minimize the likelihood of loss of signal and cycle slip, bank angles of remote-sensing survey airplanes have generally been limited to 10 or less, resulting in skidding or slipping uncoordinated turns. An airplane must be banked in order to make

  8. Profiles of Receptive and Expressive Language Abilities in Boys with Comorbid Fragile X Syndrome and Autism

    Science.gov (United States)

    McDuffie, Andrea; Kover, Sara; Abbeduto, Leonard; Lewis, Pamela; Brown, Ted

    2012-01-01

    The authors examined receptive and expressive language profiles for a group of verbal male children and adolescents who had fragile X syndrome along with varying degrees of autism symptoms. A categorical approach for assigning autism diagnostic classification, based on the combined use of the Autism Diagnostic Interview--Revised and the Autism…

  9. Socioemotional Competence, Self-Perceptions, and Receptive Vocabulary in Shy Canadian Children

    Science.gov (United States)

    Bosacki, Sandra

    2012-01-01

    Given existing gendered stereotypic assumptions regarding shyness and children's school competencies, this study explored relations among socioemotional competencies, self-perceptions, and receptive vocabulary in shy children. Ninety-one Canadian children (52 girls, 39 boys; 5-8 years) were classified as shy (n = 26) based on teachers' behavioural…

  10. How to Explain Receptivity to Conjunction-Fallacy Inhibition Training: Evidence from the Iowa Gambling Task

    Science.gov (United States)

    Cassotti, Mathieu; Moutier, Sylvain

    2010-01-01

    Intuitive predictions and judgments under conditions of uncertainty are often mediated by judgment heuristics that sometimes lead to biases. Using the classical conjunction bias example, the present study examines the relationship between receptivity to metacognitive executive training and emotion-based learning ability indexed by Iowa Gambling…

  11. Constructing an Online Test Framework, Using the Example of a Sign Language Receptive Skills Test

    Science.gov (United States)

    Haug, Tobias; Herman, Rosalind; Woll, Bencie

    2015-01-01

    This paper presents the features of an online test framework for a receptive skills test that has been adapted, based on a British template, into different sign languages. The online test includes features that meet the needs of the different sign language versions. Features such as usability of the test, automatic saving of scores, and score…

  12. Compliments and receptivity to a courtship request: a field experiment.

    Science.gov (United States)

    Guéguen, Nicolas; Fischer-Lokou, Jacques; Lamy, Lubomir

    2013-02-01

    160 young women were solicited in the street to have a drink with a young male confederate. In the ingratiation condition, the solicitor complimented the woman regarding her physical appearance before making the request, while in the no-compliment condition, the confederate asked his request directly. Results showed that complimenting was associated with greater compliance to the request.

  13. Multi-reception strategy with improved SNR for multichannel MR imaging.

    Directory of Open Access Journals (Sweden)

    Bing Wu

    Full Text Available A multi-reception strategy with extended GRAPPA is proposed in this work to improve MR imaging performance at ultra-high field MR systems with limited receiver channels. In this method, coil elements are separated to two or more groups under appropriate grouping criteria. Those groups are enabled in sequence for imaging first, and then parallel acquisition is performed to compensate for the redundant scan time caused by the multiple receptions. To efficiently reconstruct the data acquired from elements of each group, a specific extended GRAPPA was developed. This approach was evaluated by using a 16-element head array on a 7 Tesla whole-body MRI scanner with 8 receive channels. The in-vivo experiments demonstrate that with the same scan time, the 16-element array with twice receptions and acceleration rate of 2 can achieve significant SNR gain in the periphery area of the brain and keep nearly the same SNR in the center area over an eight-element array, which indicates the proposed multi-reception strategy and extended GRAPPA are feasible to improve image quality for MRI systems with limited receive channels. This study also suggests that it is advantageous for a MR system with N receiver channels to utilize a coil array with more than N elements if an appropriate acquisition strategy is applied.

  14. Magnetic Field Measurements Based on Terfenol Coated Photonic Crystal Fibers

    Science.gov (United States)

    Quintero, Sully M. M.; Martelli, Cicero; Braga, Arthur M. B.; Valente, Luiz C. G.; Kato, Carla C.

    2011-01-01

    A magnetic field sensor based on the integration of a high birefringence photonic crystal fiber and a composite material made of Terfenol particles and an epoxy resin is proposed. An in-fiber modal interferometer is assembled by evenly exciting both eigenemodes of the HiBi fiber. Changes in the cavity length as well as the effective refractive index are induced by exposing the sensor head to magnetic fields. The magnetic field sensor has a sensitivity of 0.006 (nm/mT) over a range from 0 to 300 mT with a resolution about ±1 mT. A fiber Bragg grating magnetic field sensor is also fabricated and employed to characterize the response of Terfenol composite to the magnetic field. PMID:22247655

  15. Magnetic Field Measurements Based on Terfenol Coated Photonic Crystal Fibers

    Directory of Open Access Journals (Sweden)

    Carla C. Kato

    2011-11-01

    Full Text Available A magnetic field sensor based on the integration of a high birefringence photonic crystal fiber and a composite material made of Terfenol particles and an epoxy resin is proposed. An in-fiber modal interferometer is assembled by evenly exciting both eigenemodes of the HiBi fiber. Changes in the cavity length as well as the effective refractive index are induced by exposing the sensor head to magnetic fields. The magnetic field sensor has a sensitivity of 0.006 (nm/mT over a range from 0 to 300 mT with a resolution about ±1 mT. A fiber Bragg grating magnetic field sensor is also fabricated and employed to characterize the response of Terfenol composite to the magnetic field.

  16. Hybrid quantum repeater based on resonant qubit-field interactions

    Science.gov (United States)

    Bernád, József Zsolt

    2017-11-01

    We propose a hybrid quantum repeater based on ancillary coherent field states and material qubits coupled to optical cavities. For this purpose, resonant qubit-field interactions and postselective field measurements are determined which are capable of realizing all necessary two-qubit operations for the actuation of the quantum repeater. We explore both theoretical and experimental possibilities of generating near-maximally-entangled qubit pairs (F >0.999 ) over long distances. It is shown that our scheme displays moderately low repeater rates, between 5 ×10-4 and 23 pairs per second, over distances up to 900 km, and it relies completely on current technology of cavity quantum electrodynamics.

  17. Improved nowcasting of precipitation based on convective analysis fields

    Directory of Open Access Journals (Sweden)

    T. Haiden

    2007-04-01

    Full Text Available The high-resolution analysis and nowcasting system INCA (Integrated Nowcasting through Comprehensive Analysis developed at the Austrian national weather service provides three-dimensional fields of temperature, humidity, and wind on an hourly basis, and two-dimensional fields of precipitation rate in 15 min intervals. The system operates on a horizontal resolution of 1 km and a vertical resolution of 100–200 m. It combines surface station data, remote sensing data (radar, satellite, forecast fields of the numerical weather prediction model ALADIN, and high-resolution topographic data. An important application of the INCA system is nowcasting of convective precipitation. Based on fine-scale temperature, humidity, and wind analyses a number of convective analysis fields are routinely generated. These fields include convective boundary layer (CBL flow convergence and specific humidity, lifted condensation level (LCL, convective available potential energy (CAPE, convective inhibition (CIN, and various convective stability indices. Based on the verification of areal precipitation nowcasts it is shown that the pure translational forecast of convective cells can be improved by using a decision algorithm which is based on a subset of the above fields, combined with satellite products.

  18. Developmental Stages in Receptive Grammar Acquisition: A Processability Theory Account

    Science.gov (United States)

    Buyl, Aafke; Housen, Alex

    2015-01-01

    This study takes a new look at the topic of developmental stages in the second language (L2) acquisition of morphosyntax by analysing receptive learner data, a language mode that has hitherto received very little attention within this strand of research (for a recent and rare study, see Spinner, 2013). Looking at both the receptive and productive…

  19. First-year university students' receptive and productive use of ...

    African Journals Online (AJOL)

    The present study explores academic vocabulary knowledge, operationalised through the Academic Word List, among first-year higher education students. Both receptive and productive knowledge and the proportion between the two are examined. Results show that while receptive knowledge is readily acquired by ...

  20. The Comparative Reception of Darwinism: A Brief History

    Science.gov (United States)

    Glick, Thomas F.

    2010-01-01

    The subfield of Darwin studies devoted to comparative reception coalesced around 1971 with the planning of a conference on the subject, at the University of Texas at Austin held in April 1972. The original focus was western Europe, Russia and the United States. Subsequently a spate of studies on the Italian reception added to the Eurocentric…

  1. First-year university students' receptive and productive use of ...

    African Journals Online (AJOL)

    Kate H

    Academic Word List (AWL)) and students from the same class, who are thus of comparable linguistic ... Language (EFL) students, which it complements by making estimates of the ratio between receptive and ... students' receptive vocabulary size provides teachers with a gauge as to whether those students will be able to ...

  2. Evaluation of pollen viability, stigma receptivity and fertilization ...

    African Journals Online (AJOL)

    AJL

    2013-11-13

    Nov 13, 2013 ... To provide theoretical basis for artificial pollination in Lagerstroemia indica L., pollen viability and stigma receptivity were tested and the morphological change of stigma was observed. Pollen viability tested by in vitro culture, stigma receptivity examined by benzidine-H2O2 testing and fruit set estimated.

  3. Cross-National Policy Borrowing: Understanding Reception and Translation

    Science.gov (United States)

    Steiner-Khamsi, Gita

    2014-01-01

    The article examines two key concepts in research on policy borrowing and lending that are often used to explain why and how educational reforms travel across national boundaries: reception and translation. The studies on reception analyse the political, economic, and cultural reasons that account for the attractiveness of a reform from elsewhere.…

  4. Teacher Empowerment and Receptivity in Curriculum Reform in China

    Science.gov (United States)

    Lee, John Chi-Kin; Yin, Hong-Biao; Zhang, Zhong-Hua; Jin, Yu-Le

    2011-01-01

    This study explores the relationships between teacher empowerment, teacher receptivity toward, and perceived outcomes of, a system-wide curriculum change, particularly national curriculum reform in basic education in China. The results of a survey of 1,646 teachers from six provinces indicate that teachers were positive in their receptivity and…

  5. Dipole-magnet field models based on a conformal map

    Directory of Open Access Journals (Sweden)

    P. L. Walstrom

    2012-10-01

    Full Text Available In general, generation of charged-particle transfer maps for conventional iron-pole-piece dipole magnets to third and higher order requires a model for the midplane field profile and its transverse derivatives (soft-edge model to high order and numerical integration of map coefficients. An exact treatment of the problem for a particular magnet requires use of measured magnetic data. However, in initial design of beam transport systems, users of charged-particle optics codes generally rely on magnet models built into the codes. Indeed, if maps to third order are adequate for the problem, an approximate analytic field model together with numerical map coefficient integration can capture the important features of the transfer map. The model described in this paper is based on the fact that, except at very large distances from the magnet, the magnetic field for parallel pole-face magnets with constant pole gap height and wide pole faces is basically two dimensional (2D. The field for all space outside of the pole pieces is given by a single (complex analytic expression and includes a parameter that controls the rate of falloff of the fringe field. Since the field function is analytic in the complex plane outside of the pole pieces, it satisfies two basic requirements of a field model for higher-order map codes: it is infinitely differentiable at the midplane and also a solution of the Laplace equation. It is apparently the only simple model available that combines an exponential approach to the central field with an inverse cubic falloff of field at large distances from the magnet in a single expression. The model is not intended for detailed fitting of magnetic field data, but for use in numerical map-generating codes for studying the effect of extended fringe fields on higher-order transfer maps. It is based on conformally mapping the area between the pole pieces to the upper half plane, and placing current filaments on the pole faces. An

  6. Unaccompanied adolescents seeking asylum - Poorer mental health under a restrictive reception : poorer mental health under a restrictive reception

    NARCIS (Netherlands)

    Reijneveld, S.A.; de Boer, J.B.; Bean, T.; Korfker, D.G.

    2005-01-01

    We assessed the effects of a stringent reception policy on the mental health of unaccompanied adolescent asylum seekers by comparing the mental health of adolescents in a restricted campus reception setting and in a setting offering more autonomy (numbers [response rates]: 69 [93%] and 53 [69%],

  7. A ferrofluid based artificial tactile sensor with magnetic field control

    Energy Technology Data Exchange (ETDEWEB)

    Volkova, T.I., E-mail: tatiana.volkova@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Böhm, V., E-mail: valter.boehm@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Naletova, V.A., E-mail: naletova@imec.msu.ru [Faculty of Mechanics and Mathematics, Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Kaufhold, T., E-mail: tobias.kaufhold@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Becker, F., E-mail: felix.becker@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Zeidis, I., E-mail: igor.zeidis@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany); Zimmermann, K., E-mail: klaus.zimmermann@tu-ilmenau.de [Technical Mechanics Group, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau D-98684 (Germany)

    2017-06-01

    The paper deals with a tactile sensor inspired by biological hairs of mammals. The working principle is based on the effect of the magnetic force exerted on a paramagnetic body submerged into a ferrofluid volume under the influence of a nonuniform magnetic field. The deflection of the sensor's rod caused by external mechanical stimuli may be unambiguously identified by the distortion of the magnetic field, which occurs due to the motion of the attached body in the ferrofluid. The magnetic force acting on the body is evaluated experimentally and theoretically for the nonuniform magnetic field of a permanent magnet. The controlled oscillations of the rod are realised by applying a nonuniform magnetic field of periodically altering direction. - Highlights: • A design approach of a tactile sensor inspired by special mammalian hairs is presented. • The working principle is based on magnetic properties of a ferrofluid in magnetic fields. • The magnetic force acting on a body submerged into a ferrofluid volume is evaluated. • External mechanical stimuli may be identified by the distortion of the magnetic field. • The controlled whisking-like oscillations of the sensor's rod are realised experimentally.

  8. Field-based physiological testing of wheelchair athletes.

    Science.gov (United States)

    Goosey-Tolfrey, Victoria L; Leicht, Christof A

    2013-02-01

    The volume of literature on field-based physiological testing of wheelchair sports, such as basketball, rugby and tennis, is considerably smaller when compared with that available for individuals and team athletes in able-bodied (AB) sports. In analogy to the AB literature, it is recognized that performance in wheelchair sports not only relies on fitness, but also sport-specific skills, experience and technical proficiency. However, in contrast to AB sports, two major components contribute towards 'wheeled sports' performance, which are the athlete and the wheelchair. It is the interaction of these two that enable wheelchair propulsion and the sporting movements required within a given sport. Like any other athlete, participants of wheelchair sports are looking for efficient ways to train and/or analyse their technique and fitness to improve their performance. Consequently, laboratory and/or field-based physiological monitoring tools used at regular intervals at key time points throughout the year must be considered to help with training evaluation. The present review examines methods available in the literature to assess wheelchair sports fitness in a field-based environment, with special attention on outcome variables, validity and reliability issues, and non-physiological influences on performance. It also lays out the context of field-based testing by providing details about the Paralympic court sports and the impacts of a disability on sporting performance. Due to the limited availability of specialized equipment for testing wheelchair-dependent participants in the laboratory, the adoption of field-based testing has become the preferred option by team coaches of wheelchair athletes. An obvious advantage of field-based testing is that large groups of athletes can be tested in less time. Furthermore, athletes are tested in their natural environment (using their normal sports wheelchair set-up and floor surface), potentially making the results of such testing

  9. Fowler Nordheim theory of carbon nanotube based field emitters

    Energy Technology Data Exchange (ETDEWEB)

    Parveen, Shama; Kumar, Avshish [Department of Physics, Jamia Millia Islamia (Central University), New Delhi (India); Husain, Samina [Centre for Nanoscience and Nanotechnology, Jamia Millia Islamia (Central University), New Delhi (India); Husain, Mushahid, E-mail: mush_reslab@rediffmail.com [Department of Physics, Jamia Millia Islamia (Central University), New Delhi (India)

    2017-01-15

    Field emission (FE) phenomena are generally explained in the frame-work of Fowler Nordheim (FN) theory which was given for flat metal surfaces. In this work, an effort has been made to present the field emission mechanism in carbon nanotubes (CNTs) which have tip type geometry at nanoscale. High aspect ratio of CNTs leads to large field enhancement factor and lower operating voltages because the electric field strength in the vicinity of the nanotubes tip can be enhanced by thousand times. The work function of nanostructure by using FN plot has been calculated with reverse engineering. With the help of modified FN equation, an important formula for effective emitting area (active area for emission of electrons) has been derived and employed to calculate the active emitting area for CNT field emitters. Therefore, it is of great interest to present a state of art study on the complete solution of FN equation for CNTs based field emitter displays. This manuscript will also provide a better understanding of calculation of different FE parameters of CNTs field emitters using FN equation.

  10. Using Wavelet Bases to Separate Scales in Quantum Field Theory

    Science.gov (United States)

    Michlin, Tracie L.

    This thesis investigates the use of Daubechies wavelets to separate scales in local quantum field theory. Field theories have an infinite number of degrees of freedom on all distance scales. Quantum field theories are believed to describe the physics of subatomic particles. These theories have no known mathematically convergent approximation methods. Daubechies wavelet bases can be used separate degrees of freedom on different distance scales. Volume and resolution truncations lead to mathematically well-defined truncated theories that can be treated using established methods. This work demonstrates that flow equation methods can be used to block diagonalize truncated field theoretic Hamiltonians by scale. This eliminates the fine scale degrees of freedom. This may lead to approximation methods and provide an understanding of how to formulate well-defined fine resolution limits.

  11. Location Fingerprint Extraction for Magnetic Field Magnitude Based Indoor Positioning

    Directory of Open Access Journals (Sweden)

    Wenhua Shao

    2016-01-01

    Full Text Available Smartphone based indoor positioning has greatly helped people in finding their positions in complex and unfamiliar buildings. One popular positioning method is by utilizing indoor magnetic field, because this feature is stable and infrastructure-free. In this method, the magnetometer embedded on the smartphone measures indoor magnetic field and queries its position. However, the environments of the magnetometer are rather harsh. This harshness mainly consists of coarse-grained hard/soft-iron calibrations and sensor electronic noise. The two kinds of interferences decrease the position distinguishability of the magnetic field. Therefore, it is important to extract location features from magnetic fields to reduce these interferences. This paper analyzes the main interference sources of the magnetometer embedded on the smartphone. In addition, we present a feature distinguishability measurement technique to evaluate the performance of different feature extraction methods. Experiments revealed that selected fingerprints will improve position distinguishability.

  12. MEMS magnetic field sensor based on silicon bridge structure

    Energy Technology Data Exchange (ETDEWEB)

    Du Guangtao; Chen Xiangdong; Lin Qibin; Li Hui; Guo Huihui, E-mail: xdchen@home.swjtu.edu.c [School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031 (China)

    2010-10-15

    A MEMS piezoresistive magnetic field sensor based on a silicon bridge structure has been simulated and tested. The sensor consists of a silicon sensitivity diaphragm embedded with a piezoresistive Wheatstone bridge, and a ferromagnetic magnet adhered to the sensitivity diaphragm. When the sensor is subjected to an external magnetic field, the magnetic force bends the silicon sensitivity diaphragm, producing stress and resistors change of the Wheatstone bridge and the output voltage of the sensor. Good agreement is observed between the theory and measurement behavior of the magnetic field sensor. Experimental results demonstrate that the maximum sensitivity and minimum resolution are 48 m V/T and 160 {mu}T, respectively, making this device suitable for strong magnetic field measurement. Research results indicate that the sensor repeatability and dynamic response time are about 0.66% and 150 ms, respectively. (semiconductor devices)

  13. Human health risk assessment of synthetic turf fields based upon investigation of five fields in Connecticut.

    Science.gov (United States)

    Ginsberg, Gary; Toal, Brian; Simcox, Nancy; Bracker, Anne; Golembiewski, Brian; Kurland, Tara; Hedman, Curtis

    2011-01-01

    Questions have been raised regarding possible exposures when playing sports on synthetic turf fields cushioned with crumb rubber. Rubber is a complex mixture with some components possessing toxic and carcinogenic properties. Exposure is possible via inhalation, given that chemicals emitted from rubber might end up in the breathing zone of players and these players have high ventilation rates. Previous studies provide useful data but are limited with respect to the variety of fields and scenarios evaluated. The State of Connecticut investigated emissions associated with four outdoor and one indoor synthetic turf field under summer conditions. On-field and background locations were sampled using a variety of stationary and personal samplers. More than 20 chemicals of potential concern (COPC) were found to be above background and possibly field-related on both indoor and outdoor fields. These COPC were entered into separate risk assessments (1) for outdoor and indoor fields and (2) for children and adults. Exposure concentrations were prorated for time spent away from the fields and inhalation rates were adjusted for play activity and for children's greater ventilation than adults. Cancer and noncancer risk levels were at or below de minimis levels of concern. The scenario with the highest exposure was children playing on the indoor field. The acute hazard index (HI) for this scenario approached unity, suggesting a potential concern, although there was great uncertainty with this estimate. The main contributor was benzothiazole, a rubber-related semivolatile organic chemical (SVOC) that was 14-fold higher indoors than outdoors. Based upon these findings, outdoor and indoor synthetic turf fields are not associated with elevated adverse health risks. However, it would be prudent for building operators to provide adequate ventilation to prevent a buildup of rubber-related volatile organic chemicals (VOC) and SVOC at indoor fields. The current results are generally

  14. Field calibration of binocular stereo vision based on fast reconstruction of 3D control field

    Science.gov (United States)

    Zhang, Haijun; Liu, Changjie; Fu, Luhua; Guo, Yin

    2015-08-01

    Construction of high-speed railway in China has entered a period of rapid growth. To accurately and quickly obtain the dynamic envelope curve of high-speed vehicle is an important guarantee for safe driving. The measuring system is based on binocular stereo vision. Considering the difficulties in field calibration such as environmental changes and time limits, carried out a field calibration method based on fast reconstruction of three-dimensional control field. With the rapid assembly of pre-calibrated three-dimensional control field, whose coordinate accuracy is guaranteed by manufacture accuracy and calibrated by V-STARS, two cameras take a quick shot of it at the same time. The field calibration parameters are then solved by the method combining linear solution with nonlinear optimization. Experimental results showed that the measurement accuracy can reach up to +/- 0.5mm, and more importantly, in the premise of guaranteeing accuracy, the speed of the calibration and the portability of the devices have been improved considerably.

  15. Patch near field acoustic holography based on particle velocity measurements

    DEFF Research Database (Denmark)

    Zhang, Yong-Bin; Jacobsen, Finn; Bi, Chuan-Xing

    2009-01-01

    Patch near field acoustic holography (PNAH) based on sound pressure measurements makes it possible to reconstruct the source field near a source by measuring the sound pressure at positions on a surface. that is comparable in size to the source region of concern. Particle velocity is an alternative...... input quantity for NAH, and the advantage of using the normal component of the particle velocity rather than the sound pressure as the input of conventional spatial Fourier transform based NAH and as the input of the statistically optimized variant of NAH has recently been demonstrated. This paper......, PNAH based on particle velocity measurements can give better results than the pressure-based PNAH with a reduced number of iterations. A simulation study, as well as an experiment carried out with a pressure-velocity sound intensity probe, demonstrates these findings....

  16. Field-Based Concerns about Fourth-Generation Evaluation Theory.

    Science.gov (United States)

    Lai, Morris K.

    Some aspects of fourth generation evaluation procedures that have been advocated by E. G. Guba and Y. S. Lincoln were examined empirically, with emphasis on areas where there have been discrepancies between theory and field-based experience. In fourth generation evaluation, the product of an evaluation is not a set of conclusions, recommendations,…

  17. Field-based validation of a tactile navigation device

    NARCIS (Netherlands)

    Elliott, L.R.; Erp, J. van; Redden, E.S.; Duistermaat, M.

    2010-01-01

    In this paper, we present three field-based evaluations of a tactile land navigation system. In Experiment 1, we transition from a laboratory setting to rugged terrain used to train US Army soldier land navigation. Navigation in this challenging terrain requires careful attention to one's

  18. Field-based Teacher Education for Greater Cultural Sensitivity.

    Science.gov (United States)

    Cwick, Simin; Wooldridge, Deborah; Petch-Hogan, Beverly

    2001-01-01

    Southeast Missouri State University revised its teacher education program to include field-based experiences in each of its four blocks of courses. Student teachers are placed in rural and urban schools with pupils from various socioeconomic, cultural, racial, and disability groups. A survey of 225 cooperating teachers and student teachers…

  19. Image-based thresholds for weeds in maize fields

    DEFF Research Database (Denmark)

    Asif, Ali; Streibig, Jens Carl; Christensen, Svend

    2015-01-01

    in some parts of the field and if late germinating weeds do not affect yield, it may not be necessary the spray such places from an economic point of view. Consequently, it makes sense to develop weed control thresholds for patch spraying, based on weed cover early in the growing season. In Danish maize...

  20. Structural mapping based on potential field and remote sensing data ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 126; Issue 6. Structural mapping based on potential field and remote sensing data, South Rewa Gondwana Basin, India. Swarnapriya Chowdari Bijendra Singh B Nageswara Rao Niraj Kumar A P Singh D V Chandrasekhar. Volume 126 Issue 6 August 2017 Article ...

  1. Participative Critical Enquiry in Graduate Field-Based Learning

    Science.gov (United States)

    Reilly, Kathy; Clavin, Alma; Morrissey, John

    2016-01-01

    This paper outlines a critical pedagogic approach to field-based learning (FBL) at graduate level. Drawing on student experience stemming from a FBL module and as part of an MA programme in Environment, Society and Development, the paper addresses the complexities associated with student-led, participative critical enquiry during fieldwork in…

  2. Near-field acoustic imaging based on Laplacian sparsity

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Daudet, Laurent

    2016-01-01

    We present a sound source identification method for near-field acoustic imaging of extended sources. The methodology is based on a wave superposition method (or equivalent source method) that promotes solutions with sparse higher order spatial derivatives. Instead of promoting direct sparsity...

  3. Electromechanical field effect transistors based on multilayer phosphorene nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Z.T., E-mail: jiangzhaotan@hotmail.com; Lv, Z.T.; Zhang, X.D.

    2017-06-21

    Based on the tight-binding Hamiltonian approach, we demonstrate that the electromechanical field effect transistors (FETs) can be realized by using the multilayer phosphorene nanoribbons (PNRs). The synergistic combination of the electric field and the external strains can establish the on–off switching since the electric field can shift or split the energy band, and the mechanical strains can widen or narrow the band widths. This kind of multilayer PNR FETs, much solider than the monolayer PNR one and more easily biased by different electric fields, has more transport channels consequently leading to the higher on–off current ratio or the higher sensitivity to the electric fields. Meanwhile, the strain-induced band-flattening will be beneficial for improving the flexibility in designing the electromechanical FETs. In addition, such electromechanical FETs can act as strain-controlled FETs or mechanical detectors for detecting the strains, indicating their potential applications in nano- and micro-electromechanical fields. - Highlights: • Electromechanical transistors are designed with multilayer phosphorene nanoribbons. • Electromechanical synergistic effect can establish the on–off switching more flexibly. • Multilayer transistors, solider and more easily biased, has more transport channels. • Electromechanical transistors can act as strain-controlled transistors or mechanical detectors.

  4. Volume-based Representation of the Magnetic Field

    CERN Document Server

    Amapane, N; Drollinger, V; Karimäki, V; Klyukhin, V; Todorov, T

    2005-01-01

    Simulation and reconstruction of events in high-energy experiments require the knowledge of the value of the magnetic field at any point within the detector. The way this information is extracted from the actual map of the magnetic field and served to simulation and reconstruction applications has a large impact on accuracy and performance in terms of speed. As an example, the CMS high level trigger performs on-line tracking of muons within the magnet yoke, where the field is discontinuous and largely inhomogeneous. In this case the high level trigger execution time is dominated by the time needed to access the magnetic field map.For this reason, an optimized approach for the access to the CMS field was developed, based on a dedicated representation of thedetector geometry. The detector is modeled in terms of volumes, constructed in such a way that their boundaries correspond to the fiel d discontinuities due to changes in the magnetic permeability of the materials. The field within each volume is therefore c...

  5. Theory of Carbon Nanotube (CNT)-Based Electron Field Emitters

    Science.gov (United States)

    Bocharov, Grigory S.; Eletskii, Alexander V.

    2013-01-01

    Theoretical problems arising in connection with development and operation of electron field emitters on the basis of carbon nanotubes are reviewed. The physical aspects of electron field emission that underlie the unique emission properties of carbon nanotubes (CNTs) are considered. Physical effects and phenomena affecting the emission characteristics of CNT cathodes are analyzed. Effects given particular attention include: the electric field amplification near a CNT tip with taking into account the shape of the tip, the deviation from the vertical orientation of nanotubes and electrical field-induced alignment of those; electric field screening by neighboring nanotubes; statistical spread of the parameters of the individual CNTs comprising the cathode; the thermal effects resulting in degradation of nanotubes during emission. Simultaneous consideration of the above-listed effects permitted the development of the optimization procedure for CNT array in terms of the maximum reachable emission current density. In accordance with this procedure, the optimum inter-tube distance in the array depends on the region of the external voltage applied. The phenomenon of self-misalignment of nanotubes in an array has been predicted and analyzed in terms of the recent experiments performed. A mechanism of degradation of CNT-based electron field emitters has been analyzed consisting of the bombardment of the emitters by ions formed as a result of electron impact ionization of the residual gas molecules. PMID:28348342

  6. Theory of Carbon Nanotube (CNT-Based Electron Field Emitters

    Directory of Open Access Journals (Sweden)

    Alexander V. Eletskii

    2013-07-01

    Full Text Available Theoretical problems arising in connection with development and operation of electron field emitters on the basis of carbon nanotubes are reviewed. The physical aspects of electron field emission that underlie the unique emission properties of carbon nanotubes (CNTs are considered. Physical effects and phenomena affecting the emission characteristics of CNT cathodes are analyzed. Effects given particular attention include: the electric field amplification near a CNT tip with taking into account the shape of the tip, the deviation from the vertical orientation of nanotubes and electrical field-induced alignment of those; electric field screening by neighboring nanotubes; statistical spread of the parameters of the individual CNTs comprising the cathode; the thermal effects resulting in degradation of nanotubes during emission. Simultaneous consideration of the above-listed effects permitted the development of the optimization procedure for CNT array in terms of the maximum reachable emission current density. In accordance with this procedure, the optimum inter-tube distance in the array depends on the region of the external voltage applied. The phenomenon of self-misalignment of nanotubes in an array has been predicted and analyzed in terms of the recent experiments performed. A mechanism of degradation of CNT-based electron field emitters has been analyzed consisting of the bombardment of the emitters by ions formed as a result of electron impact ionization of the residual gas molecules.

  7. Receptivity to Tobacco Advertising and Susceptibility to Tobacco Products.

    Science.gov (United States)

    Pierce, John P; Sargent, James D; White, Martha M; Borek, Nicolette; Portnoy, David B; Green, Victoria R; Kaufman, Annette R; Stanton, Cassandra A; Bansal-Travers, Maansi; Strong, David R; Pearson, Jennifer L; Coleman, Blair N; Leas, Eric; Noble, Madison L; Trinidad, Dennis R; Moran, Meghan B; Carusi, Charles; Hyland, Andrew; Messer, Karen

    2017-06-01

    Non-cigarette tobacco marketing is less regulated and may promote cigarette smoking among adolescents. We quantified receptivity to advertising for multiple tobacco products and hypothesized associations with susceptibility to cigarette smoking. Wave 1 of the nationally representative PATH (Population Assessment of Tobacco and Health) study interviewed 10 751 adolescents who had never used tobacco. A stratified random selection of 5 advertisements for each of cigarettes, e-cigarettes, smokeless products, and cigars were shown from 959 recent tobacco advertisements. Aided recall was classified as low receptivity, and image-liking or favorite ad as higher receptivity. The main dependent variable was susceptibility to cigarette smoking. Among US youth, 41% of 12 to 13 year olds and half of older adolescents were receptive to at least 1 tobacco advertisement. Across each age group, receptivity to advertising was highest for e-cigarettes (28%-33%) followed by cigarettes (22%-25%), smokeless tobacco (15%-21%), and cigars (8%-13%). E-cigarette ads shown on television had the highest recall. Among cigarette-susceptible adolescents, receptivity to e-cigarette advertising (39.7%; 95% confidence interval [CI]: 37.9%-41.6%) was higher than for cigarette advertising (31.7%; 95% CI: 29.9%-33.6%). Receptivity to advertising for each tobacco product was associated with increased susceptibility to cigarette smoking, with no significant difference across products (similar odds for both cigarette and e-cigarette advertising; adjusted odds ratio = 1.22; 95% CI: 1.09-1.37). A large proportion of US adolescent never tobacco users are receptive to tobacco advertising, with television advertising for e-cigarettes having the highest recall. Receptivity to advertising for each non-cigarette tobacco product was associated with susceptibility to smoke cigarettes. Copyright © 2017 by the American Academy of Pediatrics.

  8. Localized Dictionaries Based Orientation Field Estimation for Latent Fingerprints.

    Science.gov (United States)

    Xiao Yang; Jianjiang Feng; Jie Zhou

    2014-05-01

    Dictionary based orientation field estimation approach has shown promising performance for latent fingerprints. In this paper, we seek to exploit stronger prior knowledge of fingerprints in order to further improve the performance. Realizing that ridge orientations at different locations of fingerprints have different characteristics, we propose a localized dictionaries-based orientation field estimation algorithm, in which noisy orientation patch at a location output by a local estimation approach is replaced by real orientation patch in the local dictionary at the same location. The precondition of applying localized dictionaries is that the pose of the latent fingerprint needs to be estimated. We propose a Hough transform-based fingerprint pose estimation algorithm, in which the predictions about fingerprint pose made by all orientation patches in the latent fingerprint are accumulated. Experimental results on challenging latent fingerprint datasets show the proposed method outperforms previous ones markedly.

  9. Magnetic field sensor using a polymer-based vibrator

    Science.gov (United States)

    Wu, Jiang; Hasebe, Kazuhiko; Mizuno, Yosuke; Tabaru, Marie; Nakamura, Kentaro

    2016-09-01

    In this technical note, a polymer-based magnetic sensor with a high resolution was devised for sensing the high magnetic field. It consisted of a bimorph (vibrator) made of poly (phenylene sulfide) (PPS) and a phosphor-bronze foil glued on the free end of the bimorph. According to Faraday’s law of induction, when a magnetic field in the direction perpendicular to the bimorph was applied, the foil cut the magnetic flux, and generated an alternating voltage across the leads at the natural frequency of the bimorph. Because PPS has low mechanical loss, low elastic modulus, and low density, high vibration velocity can be achieved if it is employed as the elastomer of the bimorph. The devised sensor was tested in the magnetic field range of 0.1-570 mT and exhibited a minimum detectable magnetic field of 0.1 mT. At a zero-to-peak driving voltage of 60 V, the sensitivity of the PPS-based magnetic sensor reached 10.5 V T-1, which was 1.36 times the value of the aluminum-based magnetic sensor with the same principle and dimensions.

  10. Statistical analysis of ground based magnetic field measurements with the field line resonance detector

    Directory of Open Access Journals (Sweden)

    F. Plaschke

    2008-11-01

    Full Text Available In this paper we introduce the field line resonance detector (FLRD, a wave telescope technique which has been specially adapted to estimate the spectral energy density of field line resonance (FLR phase structures in a superposed wave field. The field line resonance detector is able to detect and correctly characterize several superposed FLR structures of a wave field and therefore constitutes a new and powerful tool in ULF pulsation studies. In our work we derive the technique from the classical wave telescope beamformer and present a statistical analysis of one year of ground based magnetometer data from the Canadian magnetometer network CANOPUS, now known as CARISMA. The statistical analysis shows that the FLRD is capable of detecting and characterizing superposed or hidden FLR structures in most of the detected ULF pulsation events; the one year statistical database is therefore extraordinarily comprehensive. The results of this analysis confirm the results of previous FLR characterizations and furthermore allow a detailed generalized dispersion analysis of FLRs.

  11. Antenna Automation For NOAA Satellite Images Reception

    Science.gov (United States)

    Rahal, W. L.; Benabadji, N.; Belbachir, A. H.

    2008-06-01

    In this paper, we present a novel, precise and efficient software tool (LAAR-TRACK) for Low Earth Orbit (LEO) Satellites orbit determination. It's based on using orbital elements, which are given by the NORAD (North American Aerospace Defence) by taking into considerations orbital perturbations due to the atmospheric drag, the influence of the moon and the sun and the geopotential field. The LAAR-TRACK gives the azimuth and the elevation that must have the antenna for pointing in real time the LEO satellites. This software is loaded on a computer directly connected, via the parallel port, to the tracking interface that we have developed, and which will be detailed in this paper. By this way the antenna can be automatically directed for receiving NOAA (National Oceanic and Atmospheric Administration) HRPT (High Resolution Picture Transmission) pictures.

  12. Design Optimisation of a Magnetic Field Based Soft Tactile Sensor.

    Science.gov (United States)

    Boer, Gregory de; Raske, Nicholas; Wang, Hongbo; Kow, Junwai; Alazmani, Ali; Ghajari, Mazdak; Culmer, Peter; Hewson, Robert

    2017-11-03

    This paper investigates the design optimisation of a magnetic field based soft tactile sensor, comprised of a magnet and Hall effect module separated by an elastomer. The aim was to minimise sensitivity of the output force with respect to the input magnetic field; this was achieved by varying the geometry and material properties. Finite element simulations determined the magnetic field and structural behaviour under load. Genetic programming produced phenomenological expressions describing these responses. Optimisation studies constrained by a measurable force and stable loading conditions were conducted; these produced Pareto sets of designs from which the optimal sensor characteristics were selected. The optimisation demonstrated a compromise between sensitivity and the measurable force, a fabricated version of the optimised sensor validated the improvements made using this methodology. The approach presented can be applied in general for optimising soft tactile sensor designs over a range of applications and sensing modes.

  13. Sound field reconstruction based on the acousto-optic effect

    DEFF Research Database (Denmark)

    Torras Rosell, Antoni; Barrera Figueroa, Salvador; Jacobsen, Finn

    2011-01-01

    Acoustic measurements are usually carried out with transducers that interact mechanically with the sound field under investigation. The goal of this work is to employ a completely different measurement principle, the determination of sound pressure based on the interaction between sound and light......, namely the acousto-optic effect. When sound propagates through a medium, it gives rise to pressure fluctuations that change the instantaneous density of the medium. Under such circumstances, the speed of light is not constant, but changed by the acoustic field. This acousto-optic interaction can...... be measured with a laser Doppler vibrometer; furthermore, it can be exploited to characterize an arbitrary sound field using tomographic techniques. This paper briefly reviews the fundamental principles governing the acousto-optic effect in air, and presents an investigation of the tomographic reconstruction...

  14. The Relationship between Receptive and Expressive Subskills of Academic L2 Proficiency in Nonnative Speakers of English: A Multigroup Approach

    Science.gov (United States)

    Pae, Hye K.; Greenberg, Daphne

    2014-01-01

    The purpose of this study was to examine the relationship between receptive and expressive language skills characterized by the performance of nonnative speakers (NNSs) of English in the academic context. Test scores of 585 adult NNSs were selected from Form 2 of the Pearson Test of English Academic's field-test database. A correlated…

  15. Statistical Downscaling Based on Spartan Spatial Random Fields

    Science.gov (United States)

    Hristopulos, Dionissios

    2010-05-01

    Stochastic methods of space-time interpolation and conditional simulation have been used in statistical downscaling approaches to increase the resolution of measured fields. One of the popular interpolation methods in geostatistics is kriging, also known as optimal interpolation in data assimilation. Kriging is a stochastic, linear interpolator which incorporates time/space variability by means of the variogram function. However, estimation of the variogram from data involves various assumptions and simplifications. At the same time, the high numerical complexity of kriging makes it difficult to use for very large data sets. We present a different approach based on the so-called Spartan Spatial Random Fields (SSRFs). SSRFs were motivated from classical field theories of statistical physics [1]. The SSRFs provide a different approach of parametrizing spatial dependence based on 'effective interactions,' which can be formulated based on general statistical principles or even incorporate physical constraints. This framework leads to a broad family of covariance functions [2], and it provides new perspectives in covariance parameter estimation and interpolation [3]. A significant advantage offered by SSRFs is reduced numerical complexity, which can lead to much faster codes for spatial interpolation and conditional simulation. In addition, on grids composed of rectangular cells, the SSRF representation leads to an explicit expression for the precision matrix (the inverse covariance). Therefore SSRFs could provide useful models of error covariance for data assimilation methods. We use simulated and real data to demonstrate SSRF properties and downscaled fields. keywords: interpolation, conditional simulation, precision matrix References [1] Hristopulos, D.T., 2003. Spartan Gibbs random field models for geostatistical applications, SIAM Journal in Scientific Computation, 24, 2125-2162. [2] Hristopulos, D.T., Elogne, S. N. 2007. Analytic properties and covariance

  16. Low oral receptivity for dengue type 2 viruses of Aedes albopictus from Southeast Asia compared with that of Aedes aegypti.

    Science.gov (United States)

    Vazeille, Marie; Rosen, Leon; Mousson, Laurence; Failloux, Anna-Bella

    2003-02-01

    Dengue hemorrhagic fever has been a major health problem in Asia since the 1950s. During this period, the former principal vector of dengue viruses in Asia, Aedes albopictus, was replaced by Aedes aegypti in most major cities of the area. Ae. aegypti is now considered the main vector of dengue viruses in Asia. Surprisingly, however, this mosquito has been described as having a relatively low oral receptivity for dengue viruses compared with Ae. albopictus. In the present study, we compared the relative oral receptivities of Ae. aegypti and Ae. albopictus collected in southeast Asia from both sympatric and allopatric breeding sites. In all instances, the oral receptivity of Ae. aegypti to the dengue type 2 virus used was significantly higher than that of Ae. albopictus. We also compared the relative oral receptivity of Ae. aegypti and Ae. albopictus for two other low-passage strains of dengue 2. In all instances, Ae. aegypti was significantly more receptive than Ae. albopictus. It should be noted, however, that the difference was found only for Ae. albopictus recently collected from the field (Ta Promh strain, Cambodia, 2001) and not for an Ae. albopictus strain that had been colonized for many years (Oahu strain, Hawaii, 1971). We also observed a significant increase in the infection rate of Ae. albopictus of the Ta Promh strain with increasing generations in the laboratory. These observations demonstrate the importance of considering the colonization history of mosquitoes when assessing their susceptibility to infection with dengue viruses and, perhaps, other arboviruses.

  17. A Web-Based Information System for Field Data Management

    Science.gov (United States)

    Weng, Y. H.; Sun, F. S.

    2014-12-01

    A web-based field data management system has been designed and developed to allow field geologists to store, organize, manage, and share field data online. System requirements were analyzed and clearly defined first regarding what data are to be stored, who the potential users are, and what system functions are needed in order to deliver the right data in the right way to the right user. A 3-tiered architecture was adopted to create this secure, scalable system that consists of a web browser at the front end while a database at the back end and a functional logic server in the middle. Specifically, HTML, CSS, and JavaScript were used to implement the user interface in the front-end tier, the Apache web server runs PHP scripts, and MySQL to server is used for the back-end database. The system accepts various types of field information, including image, audio, video, numeric, and text. It allows users to select data and populate them on either Google Earth or Google Maps for the examination of the spatial relations. It also makes the sharing of field data easy by converting them into XML format that is both human-readable and machine-readable, and thus ready for reuse.

  18. Resonant Magnetic Field Sensors Based On MEMS Technology

    Directory of Open Access Journals (Sweden)

    Elías Manjarrez

    2009-09-01

    Full Text Available Microelectromechanical systems (MEMS technology allows the integration of magnetic field sensors with electronic components, which presents important advantages such as small size, light weight, minimum power consumption, low cost, better sensitivity and high resolution. We present a discussion and review of resonant magnetic field sensors based on MEMS technology. In practice, these sensors exploit the Lorentz force in order to detect external magnetic fields through the displacement of resonant structures, which are measured with optical, capacitive, and piezoresistive sensing techniques. From these, the optical sensing presents immunity to electromagnetic interference (EMI and reduces the read-out electronic complexity. Moreover, piezoresistive sensing requires an easy fabrication process as well as a standard packaging. A description of the operation mechanisms, advantages and drawbacks of each sensor is considered. MEMS magnetic field sensors are a potential alternative for numerous applications, including the automotive industry, military, medical, telecommunications, oceanographic, spatial, and environment science. In addition, future markets will need the development of several sensors on a single chip for measuring different parameters such as the magnetic field, pressure, temperature and acceleration.

  19. Resonant Magnetic Field Sensors Based On MEMS Technology

    Science.gov (United States)

    Herrera-May, Agustín L.; Aguilera-Cortés, Luz A.; García-Ramírez, Pedro J.; Manjarrez, Elías

    2009-01-01

    Microelectromechanical systems (MEMS) technology allows the integration of magnetic field sensors with electronic components, which presents important advantages such as small size, light weight, minimum power consumption, low cost, better sensitivity and high resolution. We present a discussion and review of resonant magnetic field sensors based on MEMS technology. In practice, these sensors exploit the Lorentz force in order to detect external magnetic fields through the displacement of resonant structures, which are measured with optical, capacitive, and piezoresistive sensing techniques. From these, the optical sensing presents immunity to electromagnetic interference (EMI) and reduces the read-out electronic complexity. Moreover, piezoresistive sensing requires an easy fabrication process as well as a standard packaging. A description of the operation mechanisms, advantages and drawbacks of each sensor is considered. MEMS magnetic field sensors are a potential alternative for numerous applications, including the automotive industry, military, medical, telecommunications, oceanographic, spatial, and environment science. In addition, future markets will need the development of several sensors on a single chip for measuring different parameters such as the magnetic field, pressure, temperature and acceleration. PMID:22408480

  20. Geodynamics branch data base for main magnetic field analysis

    Science.gov (United States)

    Langel, Robert A.; Baldwin, R. T.

    1991-01-01

    The data sets used in geomagnetic field modeling at GSFC are described. Data are measured and obtained from a variety of information and sources. For clarity, data sets from different sources are categorized and processed separately. The data base is composed of magnetic observatory data, surface data, high quality aeromagnetic, high quality total intensity marine data, satellite data, and repeat data. These individual data categories are described in detail in a series of notebooks in the Geodynamics Branch, GSFC. This catalog reviews the original data sets, the processing history, and the final data sets available for each individual category of the data base and is to be used as a reference manual for the notebooks. Each data type used in geomagnetic field modeling has varying levels of complexity requiring specialized processing routines for satellite and observatory data and two general routines for processing aeromagnetic, marine, land survey, and repeat data.

  1. [The reception of Vesalius in Spain and England].

    Science.gov (United States)

    Portmann, Maria

    2014-01-01

    This paper discusses the depiction of engravings taken from Vesalius's, Valverde de Hamusco's and Casserio 's treatises in portraits during the 16th and the 17th centuries to understand better the reception of the Fabrica in Spain and England.

  2. Surface-Borne Time-of-Reception Measurements (STORM) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Invocon proposes the Surface-borne Time-Of-Reception Measurements (STORM) system as a method to locate the position of lightning strikes on aerospace vehicles....

  3. Near-field acoustic imaging based on Laplacian sparsity

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Daudet, Laurent

    2016-01-01

    We present a sound source identification method for near-field acoustic imaging of extended sources. The methodology is based on a wave superposition method (or equivalent source method) that promotes solutions with sparse higher order spatial derivatives. Instead of promoting direct sparsity......, and the validity of the wave extrapolation used for the reconstruction is examined. It is shown that this methodology can overcome conventional limits of spatial sampling, and is therefore valid for wide-band acoustic imaging of extended sources....

  4. Gas Sensors Based on Polymer Field-Effect Transistors

    OpenAIRE

    Aifeng Lv; Yong Pan; Lifeng Chi

    2017-01-01

    This review focuses on polymer field-effect transistor (PFET) based gas sensor with polymer as the sensing layer, which interacts with gas analyte and thus induces the change of source-drain current (?I SD). Dependent on the sensing layer which can be semiconducting polymer, dielectric layer or conducting polymer gate, the PFET sensors can be subdivided into three types. For each type of sensor, we present the molecular structure of sensing polymer, the gas analyte and the sensing performance...

  5. Receptivity to alcohol marketing predicts initiation of alcohol use

    Science.gov (United States)

    Henriksen, Lisa; Feighery, Ellen C.; Schleicher, Nina C.; Fortmann, Stephen P.

    2008-01-01

    Purpose This longitudinal study examined the influence of alcohol advertising and promotions on the initiation of alcohol use. A measure of receptivity to alcohol marketing was developed from research about tobacco marketing. Recall and recognition of alcohol brand names were also examined. Methods Data were obtained from in-class surveys of 6th, 7th, and 8th graders at baseline and 12-month follow-up. Participants who were classified as never drinkers at baseline (n=1,080) comprised the analysis sample. Logistic regression models examined the association of advertising receptivity at baseline with any alcohol use and current drinking at follow-up, adjusting for multiple risk factors, including peer alcohol use, school performance, risk taking, and demographics. Results At baseline, 29% of never drinkers either owned or wanted to use an alcohol branded promotional item (high receptivity), 12% students named the brand of their favorite alcohol ad (moderate receptivity) and 59% were not receptive to alcohol marketing. Approximately 29% of adolescents reported any alcohol use at follow-up; 13% reported drinking at least 1 or 2 days in the past month. Never drinkers who reported high receptivity to alcohol marketing at baseline were 77% more likely to initiate drinking by follow-up than those were not receptive. Smaller increases in the odds of alcohol use at follow-up were associated with better recall and recognition of alcohol brand names at baseline. Conclusions Alcohol advertising and promotions are associated with the uptake of drinking. Prevention programs may reduce adolescents’ receptivity to alcohol marketing by limiting their exposure to alcohol ads and promotions and by increasing their skepticism about the sponsors’ marketing tactics. PMID:18155027

  6. Detailed field test of yaw-based wake steering

    DEFF Research Database (Denmark)

    Fleming, P.; Churchfield, M.; Scholbrock, A.

    2016-01-01

    This paper describes a detailed field-test campaign to investigate yaw-based wake steering. In yaw-based wake steering, an upstream turbine intentionally misaligns its yaw with respect to the inflow to deflect its wake away from a downstream turbine, with the goal of increasing total power...... production. In the first phase, a nacelle-mounted scanning lidar was used to verify wake deflection of a misaligned turbine and calibrate wake deflection models. In the second phase, these models were used within a yaw controller to achieve a desired wake deflection. This paper details the experimental...

  7. Development of an LCD-Based Visual Field System.

    Science.gov (United States)

    Joo, Jin Ho; Lee, Jihyoung; You, Heecheon; Kang, Jaheon

    2018-01-15

    The present study investigated the diagnostic effectiveness of an LCD-based visual field testing system (LVF) in comparison with the standard automated perimetry Humphrey Field Analyzer II-750i (HFA). A randomized controlled crossover study was conducted with 202 normal and 128 glaucomatous eyes using both LVF and HFA. The visual field testing systems were compared in terms of mean deviation (MD), pattern standard deviation (PSD), and area under the receiver operating characteristics curve (AUC) of MD and PSD differentiating the normal and glaucomatous eyes. Significant correlations were found between MD measurements from LVF and those from HFA for normal eyes (r = 0.342) and glaucomatous eyes (r = 0.796); slightly higher significant correlations were identified between PSD measurements from LVF and those from HFA for normal eyes (r = 0.363) and glaucomatous eyes (r = 0.828). Furthermore, high AUCs of MD were found as 0.786 for LVF and 0.868 for HFA and AUCs of PSD as 0.913 for LVF and 0.932 for HFA. The comparison results of the present study support the competence of LVF compared with HFA in visual field testing for early detection of glaucoma.

  8. 2D Vector Field Simplification Based on Robustness

    KAUST Repository

    Skraba, Primoz

    2014-03-01

    Vector field simplification aims to reduce the complexity of the flow by removing features in order of their relevance and importance, to reveal prominent behavior and obtain a compact representation for interpretation. Most existing simplification techniques based on the topological skeleton successively remove pairs of critical points connected by separatrices, using distance or area-based relevance measures. These methods rely on the stable extraction of the topological skeleton, which can be difficult due to instability in numerical integration, especially when processing highly rotational flows. These geometric metrics do not consider the flow magnitude, an important physical property of the flow. In this paper, we propose a novel simplification scheme derived from the recently introduced topological notion of robustness, which provides a complementary view on flow structure compared to the traditional topological-skeleton-based approaches. Robustness enables the pruning of sets of critical points according to a quantitative measure of their stability, that is, the minimum amount of vector field perturbation required to remove them. This leads to a hierarchical simplification scheme that encodes flow magnitude in its perturbation metric. Our novel simplification algorithm is based on degree theory, has fewer boundary restrictions, and so can handle more general cases. Finally, we provide an implementation under the piecewise-linear setting and apply it to both synthetic and real-world datasets. © 2014 IEEE.

  9. Lightning-based propagation of convective rain fields

    Directory of Open Access Journals (Sweden)

    S. Dietrich

    2011-05-01

    Full Text Available This paper describes a new multi-sensor approach for continuously monitoring convective rain cells. It exploits lightning data from surface networks to propagate rain fields estimated from multi-frequency brightness temperature measurements taken by the AMSU/MHS microwave radiometers onboard NOAA/EUMETSAT low Earth orbiting operational satellites. Specifically, the method allows inferring the development (movement, morphology and intensity of convective rain cells from the spatial and temporal distribution of lightning strokes following any observation by a satellite-borne microwave radiometer. Obviously, this is particularly attractive for real-time operational purposes, due to the sporadic nature of the low Earth orbiting satellite measurements and the continuous availability of ground-based lightning measurements – as is the case in most of the Mediterranean region. A preliminary assessment of the lightning-based rainfall propagation algorithm has been successfully made by using two pairs of consecutive AMSU observations, in conjunction with lightning measurements from the ZEUS network, for two convective events. Specifically, we show that the evolving rain fields, which are estimated by applying the algorithm to the satellite-based rainfall estimates for the first AMSU overpass, show an overall agreement with the satellite-based rainfall estimates for the second AMSU overpass.

  10. On the integration of object-based models and field-based models in GIS

    OpenAIRE

    Kjenstad, Kjell

    2006-01-01

    This paper proposes a common base-model for the classical object-based and field-based conceptual models in GIS. The model, which is called the PGOModel or 'Parameterized Geographic Object Model', is given a formal definition by using the UML modelling language. Within the scope of the paper, it has been shown that the PGOModel encompasses the classical object-based and field-based models. Two extensive examples demonstrate the application of the PGO model. The PGOModel seems ontologically we...

  11. Graphene-Based Superconducting Weak Links in Low Magnetic Field

    Science.gov (United States)

    Mills, Scott; Kumaravadivel, Piranavan; Du, Xu

    The impact of magnetic field on Andreev reflection is studied in graphene-based superconducting weak links. We found, through studying weak links with different adhesion layers and superconducting leads (including Graphene-Ti/Au-Nb, Graphene-Ti/Pd-Nb, Graphene-V-Nb, Graphene-Ti-Nb, Graphene-Ti/Pd-NbN), that in low field (B graphene-superconductor interface. As the effective gap of the weak link approaches the intrinsic gap of the superconducting leads, a remnant of Andreev reflection can survive into the quantum Hall regime, allowing study of the interplay between the quantum Hall effect and Andreev reflection in high quality suspended graphene-superconductor weak links.

  12. Field-effect transistor memories based on ferroelectric polymers

    Science.gov (United States)

    Zhang, Yujia; Wang, Haiyang; Zhang, Lei; Chen, Xiaomeng; Guo, Yu; Sun, Huabin; Li, Yun

    2017-11-01

    Field-effect transistors based on ferroelectrics have attracted intensive interests, because of their non-volatile data retention, rewritability, and non-destructive read-out. In particular, polymeric materials that possess ferroelectric properties are promising for the fabrications of memory devices with high performance, low cost, and large-area manufacturing, by virtue of their good solubility, low-temperature processability, and good chemical stability. In this review, we discuss the material characteristics of ferroelectric polymers, providing an update on the current development of ferroelectric field-effect transistors (Fe-FETs) in non-volatile memory applications. Program supported partially by the NSFC (Nos. 61574074, 61774080), NSFJS (No. BK20170075), and the Open Partnership Joint Projects of NSFC–JSPS Bilateral Joint Research Projects (No. 61511140098).

  13. Approximation of Measurement Results of “Emergency” Signal Reception Probability

    Directory of Open Access Journals (Sweden)

    Gajda Stanisław

    2017-08-01

    Full Text Available The intended aim of this article is to present approximation results of the exemplary measurements of EMERGENCY signal reception probability. The probability is under-stood as a distance function between the aircraft and a ground-based system under established conditions. The measurements were approximated using the properties of logistic functions. This probability, as a distance function, enables to determine the range of the EMERGENCY signal for a pre-set confidence level.

  14. Transition Prediction in Hypersonic Boundary Layers Using Receptivity and Freestream Spectra

    Science.gov (United States)

    Balakumar, P.; Chou, Amanda

    2016-01-01

    Boundary-layer transition in hypersonic flows over a straight cone can be predicted using measured freestream spectra, receptivity, and threshold values for the wall pressure fluctuations at the transition onset points. Simulations are performed for hypersonic boundary-layer flows over a 7-degree half-angle straight cone with varying bluntness at a freestream Mach number of 10. The steady and the unsteady flow fields are obtained by solving the two-dimensional Navier-Stokes equations in axisymmetric coordinates using a 5th-order accurate weighted essentially non-oscillatory (WENO) scheme for space discretization and using a third-order total-variation-diminishing (TVD) Runge-Kutta scheme for time integration. The calculated N-factors at the transition onset location increase gradually with increasing unit Reynolds numbers for flow over a sharp cone and remain almost the same for flow over a blunt cone. The receptivity coefficient increases slightly with increasing unit Reynolds numbers. They are on the order of 4 for a sharp cone and are on the order of 1 for a blunt cone. The location of transition onset predicted from the simulation including the freestream spectrum, receptivity, and the linear and the weakly nonlinear evolutions yields a solution close to the measured onset location for the sharp cone. The simulations over-predict transition onset by about twenty percent for the blunt cone.

  15. Magnetic Field Effect in Conjugated Molecules-Based Devices

    Science.gov (United States)

    2017-10-23

    2. “The origins in the transformation of ambipolar to n-type pentacene-based organic field-effect transistors” Org. Electron. 15, 1759 (2014...J. M., Li, Y., He, Y., Trevor, M. & Park , N.-G. Dual function interfacial layer for highly efficient and stable lead halide perovskite solar cells...CH3NH3PbI3 perovskite/PCBM planar-heterojunction hybrid solar cells. Adv. Mater. 26, 4107 (2014). 20. Park , J. H., Seo, J., Park , S., Shin, S. S

  16. Health-reception of newly arrived documented migrants in Europe-why, whom, what and how?

    DEFF Research Database (Denmark)

    Frederiksen, Hanne W; Kamper-Jørgensen, Zaza; Agyemang, Charles

    2013-01-01

    address the existing health inequities, nor determining factors of migrant health, including barriers to access health services’.1 Two recent Danish documents highlight these aspects in relation to the health-reception of migrants. A report from the Ministry of Social Affairs and Integration concludes...... that present health initiatives offered to newly arrived long-term documented migrants are not systematically harmonized and updated and do not cover all relevant migrant groups.2 This is likely to be the case in many other settings across Europe. Subsequently, a new Danish bill sets out to reform the current...... Danish health-reception model, using a more systematic approach based on a close cooperation between social and health sectors.3 With this development, we wish to initiate a European public health debate about how to assess and meet the health needs of newly arrived long-term documented migrants...

  17. Vibration activity and mobility of structure-borne sound sources by a reception plate method.

    Science.gov (United States)

    Gibbs, B M; Cookson, R; Qi, N

    2008-06-01

    This paper considers a practical structure-borne sound source characterization for mechanical installations, which are connected to plate-like structures. It describes a laboratory-based measurement procedure, which will yield single values of source strength in a form transferable to a prediction of the structure-borne sound power generated in the installed condition. It is confirmed that two source quantities are required, corresponding to the source activity and mobility. For the source activity, a high-mobility reception plate method is proposed which yields a single value in the form of the sum of the squared free velocities, over the contact points. A low-mobility reception plate method also is proposed which, in conjunction with the above, yields the source mobility in the form of the average magnitude of the effective mobility, again over the contact points. Experimental case studies are described and the applicability of the laboratory data for prediction and limitations of the approach are discussed.

  18. A field-based technique for sediment incubation experiments

    Directory of Open Access Journals (Sweden)

    Rebecca C. Rooney

    2012-01-01

    Full Text Available Sediment incubation experiments have been a cornerstone in limnology for improving our understanding of sediment processes in aquatic ecosystems. Experiments are usually performed in the laboratory, which has several limitations, including: additional handling that may disturb the integrity of the sediments, the financial expense of purchasing and maintaining growth chambers and anaerobic gloveboxes, and the inability to exactly recreate the ambient environmental conditions experienced by sediments in natural ecosystems. Furthermore, laboratory-based techniques are simply not possible with flocculent sediments from eutrophic ecosystems that are highly prone to separation following changes in pressure. Here, we describe a field-based technique for incubating sediment cores that is simple, versatile, and inexpensive. Our in situ incubation technique is highly effective for exposing sediments to natural temperature, pressure, and light regimes, and easily maintaining sediments under anaerobic conditions.

  19. Recent Trends in Field-Effect Transistors-Based Immunosensors

    Directory of Open Access Journals (Sweden)

    Ana Carolina Mazarin de Moraes

    2016-10-01

    Full Text Available Immunosensors are analytical platforms that detect specific antigen-antibody interactions and play an important role in a wide range of applications in biomedical clinical diagnosis, food safety, and monitoring contaminants in the environment. Field-effect transistors (FET immunosensors have been developed as promising alternatives to conventional immunoassays, which require complicated processes and long-time data acquisition. The electrical signal of FET-based immunosensors is generated as a result of the antigen-antibody conjugation. FET biosensors present real-time and rapid response, require small sample volume, and exhibit higher sensitivity and selectivity. This review brings an overview on the recent literature of FET-based immunosensors, highlighting a diversity of nanomaterials modified with specific receptors as immunosensing platforms for the ultrasensitive detection of various biomolecules.

  20. PREDICTIVE POTENTIAL FIELD-BASED COLLISION AVOIDANCE FOR MULTICOPTERS

    Directory of Open Access Journals (Sweden)

    M. Nieuwenhuisen

    2013-08-01

    Full Text Available Reliable obstacle avoidance is a key to navigating with UAVs in the close vicinity of static and dynamic obstacles. Wheel-based mobile robots are often equipped with 2D or 3D laser range finders that cover the 2D workspace sufficiently accurate and at a high rate. Micro UAV platforms operate in a 3D environment, but the restricted payload prohibits the use of fast state-of-the-art 3D sensors. Thus, perception of small obstacles is often only possible in the vicinity of the UAV and a fast collision avoidance system is necessary. We propose a reactive collision avoidance system based on artificial potential fields, that takes the special dynamics of UAVs into account by predicting the influence of obstacles on the estimated trajectory in the near future using a learned motion model. Experimental evaluation shows that the prediction leads to smoother trajectories and allows to navigate collision-free through passageways.

  1. Computer Based Procedures for Field Workers - FY16 Research Activities

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bly, Aaron [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    The Computer-Based Procedure (CBP) research effort is a part of the Light-Water Reactor Sustainability (LWRS) Program, which provides the technical foundations for licensing and managing the long-term, safe, and economical operation of current nuclear power plants. One of the primary missions of the LWRS program is to help the U.S. nuclear industry adopt new technologies and engineering solutions that facilitate the continued safe operation of the plants and extension of the current operating licenses. One area that could yield tremendous savings in increased efficiency and safety is in improving procedure use. A CBP provides the opportunity to incorporate context-driven job aids, such as drawings, photos, and just-in-time training. The presentation of information in CBPs can be much more flexible and tailored to the task, actual plant condition, and operation mode. The dynamic presentation of the procedure will guide the user down the path of relevant steps, thus minimizing time spent by the field worker to evaluate plant conditions and decisions related to the applicability of each step. This dynamic presentation of the procedure also minimizes the risk of conducting steps out of order and/or incorrectly assessed applicability of steps. This report provides a summary of the main research activities conducted in the Computer-Based Procedures for Field Workers effort since 2012. The main focus of the report is on the research activities conducted in fiscal year 2016. The activities discussed are the Nuclear Electronic Work Packages – Enterprise Requirements initiative, the development of a design guidance for CBPs (which compiles all insights gained through the years of CBP research), the facilitation of vendor studies at the Idaho National Laboratory (INL) Advanced Test Reactor (ATR), a pilot study for how to enhance the plant design modification work process, the collection of feedback from a field evaluation study at Plant Vogtle, and path forward to

  2. A copula-based downscaling methodology of RCM precipitation fields

    Science.gov (United States)

    Lorenz, Manuel

    2016-04-01

    Many hydrological studies require long term precipitation time series at a fine spatial resolution. While regional climate models are nowadays capable of simulating reasonable high-resolution precipitation fields, the long computing time makes the generation of such long term time series often infeasible for practical purposes. We introduce a comparatively fast stochastic approach to simulate precipitation fields which resemble the spatial dependencies and density distributions of the dynamic model. Nested RCM simulations at two different spatial resolutions serve as a training set to derive the statistics which will then be used in a random path simulation where fine scale precipitation values are simulated from a multivariate Gaussian Copula. The chosen RCM is the Weather Research and Forecasting Model (WRF). Simulated daily precipitation fields of the RCM are based on ERA-Interim reanalysis data from 1971 to 2000 and are available at a spatial resolution of 42 km (Europe) and 7 km (Germany). In order to evaluate the method, the stochastic algorithm is applied to the nested German domain and the resulting spatial dependencies and density distributions are compared to the original 30 years long 7 km WRF simulations. Preliminary evaluations based on QQ-plots for one year indicate that the distributions of the downscaled values are very similar to the original values for most cells. In this presentation, a detailed overview of the stochastic downscaling algorithm and the evaluation of the long term simulations are given. Additionally, an outlook for a 5 km and 1 km downscaling experiment for urban hydrology studies is presented.

  3. Vision Sensor-Based Road Detection for Field Robot Navigation

    Directory of Open Access Journals (Sweden)

    Keyu Lu

    2015-11-01

    Full Text Available Road detection is an essential component of field robot navigation systems. Vision sensors play an important role in road detection for their great potential in environmental perception. In this paper, we propose a hierarchical vision sensor-based method for robust road detection in challenging road scenes. More specifically, for a given road image captured by an on-board vision sensor, we introduce a multiple population genetic algorithm (MPGA-based approach for efficient road vanishing point detection. Superpixel-level seeds are then selected in an unsupervised way using a clustering strategy. Then, according to the GrowCut framework, the seeds proliferate and iteratively try to occupy their neighbors. After convergence, the initial road segment is obtained. Finally, in order to achieve a globally-consistent road segment, the initial road segment is refined using the conditional random field (CRF framework, which integrates high-level information into road detection. We perform several experiments to evaluate the common performance, scale sensitivity and noise sensitivity of the proposed method. The experimental results demonstrate that the proposed method exhibits high robustness compared to the state of the art.

  4. The routes to be followed into Alberto Caeiros’s poetry: a reception aesthetics approach

    Directory of Open Access Journals (Sweden)

    Fabrício César Aguiar

    2011-10-01

    Full Text Available The aim of this article is to study the 8th poem Num meio dia de fim de primavera written by Alberto Caeiro. The analysis proposed will be based on some of the Reception Aesthetics concepts mainly focusing on enriching the sensory aspects of the text, especially the visual one. For that purpose, the poetic devices used in the construction of the text as well as its reception by the readers will be highlighted. The analysis will be based on the concepts theorized by Wolfgang Iser. Such concepts are: a the interaction between text and reader and the position of the latter at the time of the former reception; b the blank places; c the negation and negativity structures; and d it will also consider the approach to reading as an act in which the reader is responsible for achieving the meaning for the text and for creating an “aesthetic pleasure” through it. This last concept is grounded in Hans Robert Jauss theory.

  5. Receptive vocabulary and semantic knowledge in children with SLI and children with Down syndrome.

    Science.gov (United States)

    Laws, Glynis; Briscoe, Josie; Ang, Su-Yin; Brown, Heather; Hermena, Ehab; Kapikian, Anna

    2015-01-01

    Receptive vocabulary and associated semantic knowledge were compared within and between groups of children with specific language impairment (SLI), children with Down syndrome (DS), and typically developing children. To overcome the potential confounding effects of speech or language difficulties on verbal tests of semantic knowledge, a novel task was devised based on picture-based semantic association tests used to assess adult patients with semantic dementia. Receptive vocabulary, measured by word-picture matching, of children with SLI was weak relative to chronological age and to nonverbal mental age but their semantic knowledge, probed across the same lexical items, did not differ significantly from that of vocabulary-matched typically developing children. By contrast, although receptive vocabulary of children with DS was a relative strength compared to nonverbal cognitive abilities (p knowledge (p vocabulary and depth of semantic knowledge. Overall, these data challenge the integrity of semantic-conceptual development in DS and imply that contemporary theories of semantic cognition should also seek to incorporate evidence from atypical conceptual development.

  6. Rocket to Creativity: A Field Experience in Problem-Based and Project-Based Learning

    Science.gov (United States)

    Dole, Sharon F.; Bloom, Lisa A.; Doss, Kristy Kowalske

    2016-01-01

    This article reports the impact of a field experience in problem-based (PBL) and project-based learning (PjBL) on in-service teachers' conceptions of experiential learning. Participants had been enrolled in a hybrid class that included an online component in which they learned about PBL and PjBL, and an experiential component in which they…

  7. Hot Carrier-Based Near-Field Thermophotovoltaic Energy Conversion.

    Science.gov (United States)

    St-Gelais, Raphael; Bhatt, Gaurang Ravindra; Zhu, Linxiao; Fan, Shanhui; Lipson, Michal

    2017-03-28

    Near-field thermophotovoltaics (NFTPV) is a promising approach for direct conversion of heat to electrical power. This technology relies on the drastic enhancement of radiative heat transfer (compared to conventional blackbody radiation) that occurs when objects at different temperatures are brought to deep subwavelength distances (typically conversion of heat to electricity with a greater efficiency than using current solid-state technologies (e.g., thermoelectric generators). One of the main challenges in the development of this technology, however, is its incompatibility with conventional silicon PV cells. Thermal radiation is weak at frequencies larger than the ∼1.1 eV bandgap of silicon, such that PV cells with lower excitation energies (typically 0.4-0.6 eV) are required for NFTPV. Using low bandgap III-V semiconductors to circumvent this limitation, as proposed in most theoretical works, is challenging and therefore has never been achieved experimentally. In this work, we show that hot carrier PV cells based on Schottky junctions between silicon and metallic films could provide an attractive solution for achieving high efficiency NFTPV electricity generation. Hot carrier science is currently an important field of research and several approaches are investigated for increasing the quantum efficiency (QE) of hot carrier generation beyond conventional Fowler model predictions. If the Fowler limit can indeed be overcome, we show that hot carrier-based NFTPV systems-after optimization of their thermal radiation spectrum-could allow electricity generation with up to 10-30% conversion efficiencies and 10-500 W/cm 2 generated power densities (at 900-1500 K temperatures). We also discuss how the unique properties of thermal radiation in the extreme near-field are especially well suited for investigating recently proposed approaches for high QE hot carrier junctions. We therefore expect our work to be of interest for the field of hot carrier science and-by relying

  8. 1946 Dominican Republic Tsunami: Field Survey based on Eyewitness Interviews

    Science.gov (United States)

    Fritz, Hermann M.; Martinez, Claudio; Salado, Juan; Rivera, Wagner; Duarte, Leoncio

    2017-04-01

    On 4 August 1946 an Mw 8.1 earthquake struck off the north-eastern shore of Hispaniola Island resulting in a destructive tsunami with order one hundred fatalities in the Dominican Republic and observed runup in Puerto Rico. In the far field, tsunami waves were recorded on some tide gauges on the Atlantic coast of the United States of America. The earthquake devastated the Dominican Republic, extended into Haiti, and shook many other islands. This was one of the strongest earthquakes reported in the Caribbean since colonial times. The immediate earthquake reconnaissance surveys focused on earthquake damage and were conducted in September 1946 (Lynch and Bodle, 1948; Small, 1948). The 1946 Dominican Republic tsunami eyewitness based field survey took place in three phases from 18 to 21 March 2014, 1 to 3 September 2014 and 9 to 11 May 2016. The International Tsunami Survey Team (ITST) covered more than 400 km of coastline along the northern Dominican Republic from the eastern most tip at Punta Cana to La Isabela some 70 km from the border with Haiti. The survey team documented tsunami runup, flow depth, inundation distances, sea-level drawdown, coastal erosion and co-seismic land level changes based on eyewitnesses interviewed on site using established protocols. The early afternoon earthquake resulted in detailed survival stories with excellent eyewitness observations recounted almost 70 years later with lucidity. The Dominican Republic survey data includes 29 runup and tsunami height measurements at 21 locations. The tsunami impacts peaked with maximum tsunami heights exceeding 5 m at a cluster of locations between Cabrera and El Limon. A maximum tsunami height of 8 m likely associated with splash up was measured in Playa Boca Nueva. Tsunami inundation distances of 600 m or more were measured at Las Terrenas and Playa Rincon on the Samana Peninsula. Some locations were surveyed twice in 2014 and 2016, which allowed to identify current coastal erosion rates. Field

  9. A spatially based field specific crop recordkeeping system prototype ...

    African Journals Online (AJOL)

    Results have shown that a record keeping system may link crop records to respective mapped crop fields in a GIS environment. This was then used to view crop field area, update new field data in the non spatial database and query and display field data for a specified period of interest. New data were added to their ...

  10. Analysis of indirect rotor field oriented control-based induction machine performance under inaccurate field-oriented condition

    DEFF Research Database (Denmark)

    Liu, Yang; Tao, Geng; Wang, Huai

    2017-01-01

    Indirect rotor field oriented control (IRFOC) plays an important role in the high performance induction machine drives. In the indirect rotor field oriented control — based induction machine adjustable speed control system, the rotor field angle is usually obtained by the rotor angular velocity...... and the slip angular velocity. The rotor angular velocity can be sensed by an encoder with sufficient accuracy. However, the slip angular velocity is affected by the rotor parameters variations and the current control performance degradation especially in the field-weakening region. Therefore, the field angle...

  11. Gas Sensors Based on Semiconducting Nanowire Field-Effect Transistors

    Directory of Open Access Journals (Sweden)

    Ping Feng

    2014-09-01

    Full Text Available One-dimensional semiconductor nanostructures are unique sensing materials for the fabrication of gas sensors. In this article, gas sensors based on semiconducting nanowire field-effect transistors (FETs are comprehensively reviewed. Individual nanowires or nanowire network films are usually used as the active detecting channels. In these sensors, a third electrode, which serves as the gate, is used to tune the carrier concentration of the nanowires to realize better sensing performance, including sensitivity, selectivity and response time, etc. The FET parameters can be modulated by the presence of the target gases and their change relate closely to the type and concentration of the gas molecules. In addition, extra controls such as metal decoration, local heating and light irradiation can be combined with the gate electrode to tune the nanowire channel and realize more effective gas sensing. With the help of micro-fabrication techniques, these sensors can be integrated into smart systems. Finally, some challenges for the future investigation and application of nanowire field-effect gas sensors are discussed.

  12. Using the Agent-Based Modeling in Economic Field

    Directory of Open Access Journals (Sweden)

    Nora Mihail

    2006-12-01

    Full Text Available The last ten years of the XX century has been the witnesses of the apparition of a new scientific field, which is usually defined as the study of “Complex adaptive systems”. This field, generic named Complexity Sciences, shares its subject, the general proprieties of complex systems across traditional disciplinary boundaries, with cybernetics and general systems theory. But the development of Complexity Sciences approaches is determined by the extensive use of Agent-Based-Models (ABM as a research tool and an emphasis on systems, such as markets, populations or ecologies, which are less integrated or “organized” than the ones, such as companies and economies, intensively studied by the traditional disciplines. For ABM, a complex system is a system of individual agents who have the freedom to act in ways that are not always totally predictable, and whose actions are interconnected such that one agent’s actions changes the context (environment for other agents. These are many examples of such complex systems: the stock market, the human body immune system, a business organization, an institution, a work-team, a family etc.

  13. Gas Sensors Based on Semiconducting Nanowire Field-Effect Transistors

    Science.gov (United States)

    Feng, Ping; Shao, Feng; Shi, Yi; Wan, Qing

    2014-01-01

    One-dimensional semiconductor nanostructures are unique sensing materials for the fabrication of gas sensors. In this article, gas sensors based on semiconducting nanowire field-effect transistors (FETs) are comprehensively reviewed. Individual nanowires or nanowire network films are usually used as the active detecting channels. In these sensors, a third electrode, which serves as the gate, is used to tune the carrier concentration of the nanowires to realize better sensing performance, including sensitivity, selectivity and response time, etc. The FET parameters can be modulated by the presence of the target gases and their change relate closely to the type and concentration of the gas molecules. In addition, extra controls such as metal decoration, local heating and light irradiation can be combined with the gate electrode to tune the nanowire channel and realize more effective gas sensing. With the help of micro-fabrication techniques, these sensors can be integrated into smart systems. Finally, some challenges for the future investigation and application of nanowire field-effect gas sensors are discussed. PMID:25232915

  14. Tls Field Data Based Intensity Correction for Forest Environments

    Science.gov (United States)

    Heinzel, J.; Huber, M. O.

    2016-06-01

    Terrestrial laser scanning (TLS) is increasingly used for forestry applications. Besides the three dimensional point coordinates, the 'intensity' of the reflected signal plays an important role in forestry and vegetation studies. The benefit of the signal intensity is caused by the wavelength of the laser that is within the near infrared (NIR) for most scanners. The NIR is highly indicative for various vegetation characteristics. However, the intensity as recorded by most terrestrial scanners is distorted by both external and scanner specific factors. Since details about system internal alteration of the signal are often unknown to the user, model driven approaches are impractical. On the other hand, existing data driven calibration procedures require laborious acquisition of separate reference datasets or areas of homogenous reflection characteristics from the field data. In order to fill this gap, the present study introduces an approach to correct unwanted intensity variations directly from the point cloud of the field data. The focus is on the variation over range and sensor specific distortions. Instead of an absolute calibration of the values, a relative correction within the dataset is sufficient for most forestry applications. Finally, a method similar to time series detrending is presented with the only pre-condition of a relative equal distribution of forest objects and materials over range. Our test data covers 50 terrestrial scans captured with a FARO Focus 3D S120 scanner using a laser wavelength of 905 nm. Practical tests demonstrate that our correction method removes range and scanner based alterations of the intensity.

  15. Image-based Exploration of Large-Scale Pathline Fields

    KAUST Repository

    Nagoor, Omniah H.

    2014-05-27

    While real-time applications are nowadays routinely used in visualizing large nu- merical simulations and volumes, handling these large-scale datasets requires high-end graphics clusters or supercomputers to process and visualize them. However, not all users have access to powerful clusters. Therefore, it is challenging to come up with a visualization approach that provides insight to large-scale datasets on a single com- puter. Explorable images (EI) is one of the methods that allows users to handle large data on a single workstation. Although it is a view-dependent method, it combines both exploration and modification of visual aspects without re-accessing the original huge data. In this thesis, we propose a novel image-based method that applies the concept of EI in visualizing large flow-field pathlines data. The goal of our work is to provide an optimized image-based method, which scales well with the dataset size. Our approach is based on constructing a per-pixel linked list data structure in which each pixel contains a list of pathlines segments. With this view-dependent method it is possible to filter, color-code and explore large-scale flow data in real-time. In addition, optimization techniques such as early-ray termination and deferred shading are applied, which further improves the performance and scalability of our approach.

  16. Organization of receptive language-specific cortex before and after left temporal lobectomy.

    Science.gov (United States)

    Pataraia, E; Billingsley-Marshall, R L; Castillo, E M; Breier, J I; Simos, P G; Sarkari, S; Fitzgerald, M; Clear, T; Papanicolaou, A C

    2005-02-08

    To examine brain activation associated with receptive language in patients with left temporal lobe epilepsy (TLE) before and after an anterior temporal lobectomy using magnetoencephalography (MEG), and to evaluate which patients were most likely to show a change in the lateralization and localization of the mechanisms supporting receptive language and if such changes were associated with neuropsychological function. Twelve patients with left TLE underwent preoperative Wada testing, and pre- and postoperative neuropsychological testing and MEG language mapping. The anatomic location of receptive language-related activity sources observed with MEG was determined by coregistering MEG data with structural MRI scans. Language laterality indices were calculated based on the number of reproducible activity sources in each hemisphere. The proximity of language-specific activity sources to Wernicke's area was also examined. Although the small sample size precluded formal statistical analyses, patients with atypical (bilateral) hemispheric dominance preoperatively were more likely than patients with typical (left-hemisphere) dominance to show evidence of increased right hemisphere participation in language functions after surgery. Patients with left hemispheric dominance preoperatively were more likely to show intrahemispheric changes involving a slight inferior shift of the putative location of Wernicke's area. Patients with bilateral representation tended to perform worse on neuropsychological test measures obtained both pre- and postoperatively. Interhemispheric functional reorganization of language-specific areas may occur in patients undergoing left anterior temporal lobectomy. Intrahemispheric reorganization may take place even when the resection does not directly impinge upon Wernicke's area.

  17. Assessing receptivity for change in urban stormwater management and contexts for action.

    Science.gov (United States)

    Cettner, Annicka; Ashley, Richard; Hedström, Annelie; Viklander, Maria

    2014-12-15

    Individual and organisational receptivity for change towards the use of sustainable stormwater management systems has been previously examined, but the significance of the different contexts for achieving this has been largely unexplored. This paper examines the significance of contexts associated to the actions to bring this about by proposing and evaluating an emerging framework based on two related receptivity theories: the individual or organisational approach and the contextual approach. Results from a Swedish national questionnaire with professionals in stormwater management have been used, together with a limited number of interviews to develop and understand the validity of the framework. The analysis has indicated that the respondents were professionally prepared for change (action) but not practically prepared due to inadequate supportive contexts. In response, a number of potential contexts associated to the necessary actions were identified. The framework was found to provide new insights into the influence of receptive contexts for a change in water management practice. These insights can be used by policy makers and others to better support the realization of professional openness for change and thus accelerate the process of change to sustainable stormwater practice. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. RECEPTIVE AND PRODUCTIVE VOCABULARY ACQUISITION: EXAMINING PROCESSING TIME AND MEMORY THRESHOLD

    Directory of Open Access Journals (Sweden)

    Andrew Oberg

    2012-07-01

    Full Text Available Abstract: In the present research a picture card-based vocabulary study method was used to determine the pace of learner acquisition in terms of both receptive and productive knowledge. Fifty-eight first-year Japanese university students in two classes were used in the study. The subjects were placed into a single experimental group and both classes were taught by the researcher. During the treatment sessions the subjects studied fifteen vocabulary items chosen from the course textbook (Fifty-Fifty: A speaking and listening course, Book One, W. Wilson and R. Barnard, 2007, Hong Kong: Pearson Longman using self-produced picture cards. The same post-treatment test was given to the subjects following each treatment session and the results were analyzed using Paired Samples T-tests supported by non-parametric Wilcoxon matched pairs signed ranks tests by comparing one session’s data with the data of the previous session. The post-treatment data showed a significant difference between the pre-treatment and first sessions in terms of receptive knowledge, and between all sessions except the eighth and ninth in terms of productive knowledge.   Keywords: Vocabulary learning; receptive knowledge; productive knowledge; processing time; memory threshold

  19. Ferroelectric field-effect transistor based on transparent oxides

    Energy Technology Data Exchange (ETDEWEB)

    Titkov, Ilya [Department of Solid State Electronics, Ioffe Institute RAS, 26, Polytechnicheskaya str., 194021 St. Petersburg (Russian Federation)], E-mail: ititkov@mail.ioffe.ru; Pronin, Igor [Department of Solid State Electronics, Ioffe Institute RAS, 26, Polytechnicheskaya str., 194021 St. Petersburg (Russian Federation)], E-mail: petrovich@mail.ioffe.ru; Delimova, Lubov [Department of Solid State Electronics, Ioffe Institute RAS, 26, Polytechnicheskaya str., 194021 St. Petersburg (Russian Federation)], E-mail: ladel@mail.ioffe.ru; Liniichuk, Ivan [Department of Solid State Electronics, Ioffe Institute RAS, 26, Polytechnicheskaya str., 194021 St. Petersburg (Russian Federation)], E-mail: liniv@mail.ioffe.ru; Grekhov, Igor [Department of Solid State Electronics, Ioffe Institute RAS, 26, Polytechnicheskaya str., 194021 St. Petersburg (Russian Federation)], E-mail: grekhov@mail.ioffe.ru

    2007-10-15

    We studied a Pb{sub x}Zr{sub 1-x}TiO{sub 3}/SnO{sub 2}/Al{sub 2}O{sub 3} heterostructure as a base for transparent ferroelectric field-effect transistor. Single-crystal SnO{sub 2}/Al{sub 2}O{sub 3} epitaxial films with the electron mobility of 25 cm{sup 2}/V were grown by pulsed laser deposition using two YAG:Nd lasers. Depletion mode transistor Au/PZT/SnO{sub 2}/Al{sub 2}O{sub 3} was produced by laser ablation and RF sputtering. All the samples demonstrate clockwise hysteresis of the source-drain characteristic. The energy distribution of traps at the PZT/SnO{sub 2} interface was determined using a modified version of a transient current method. The effect of PZT intergrain boundaries on the retention time was taken into account for experimental data discussion.

  20. Gas Sensors Based on Polymer Field-Effect Transistors

    Science.gov (United States)

    Lv, Aifeng; Pan, Yong; Chi, Lifeng

    2017-01-01

    This review focuses on polymer field-effect transistor (PFET) based gas sensor with polymer as the sensing layer, which interacts with gas analyte and thus induces the change of source-drain current (ΔISD). Dependent on the sensing layer which can be semiconducting polymer, dielectric layer or conducting polymer gate, the PFET sensors can be subdivided into three types. For each type of sensor, we present the molecular structure of sensing polymer, the gas analyte and the sensing performance. Most importantly, we summarize various analyte–polymer interactions, which help to understand the sensing mechanism in the PFET sensors and can provide possible approaches for the sensor fabrication in the future. PMID:28117760

  1. Classification of hyperspectral images based on conditional random fields

    Science.gov (United States)

    Hu, Yang; Saber, Eli; Monteiro, Sildomar T.; Cahill, Nathan D.; Messinger, David W.

    2015-02-01

    A significant increase in the availability of high resolution hyperspectral images has led to the need for developing pertinent techniques in image analysis, such as classification. Hyperspectral images that are correlated spatially and spectrally provide ample information across the bands to benefit this purpose. Conditional Random Fields (CRFs) are discriminative models that carry several advantages over conventional techniques: no requirement of the independence assumption for observations, flexibility in defining local and pairwise potentials, and an independence between the modules of feature selection and parameter leaning. In this paper we present a framework for classifying remotely sensed imagery based on CRFs. We apply a Support Vector Machine (SVM) classifier to raw remotely sensed imagery data in order to generate more meaningful feature potentials to the CRFs model. This approach produces promising results when tested with publicly available AVIRIS Indian Pine imagery.

  2. Gas Sensors Based on Polymer Field-Effect Transistors

    Directory of Open Access Journals (Sweden)

    Aifeng Lv

    2017-01-01

    Full Text Available This review focuses on polymer field-effect transistor (PFET based gas sensor with polymer as the sensing layer, which interacts with gas analyte and thus induces the change of source-drain current (ΔISD. Dependent on the sensing layer which can be semiconducting polymer, dielectric layer or conducting polymer gate, the PFET sensors can be subdivided into three types. For each type of sensor, we present the molecular structure of sensing polymer, the gas analyte and the sensing performance. Most importantly, we summarize various analyte–polymer interactions, which help to understand the sensing mechanism in the PFET sensors and can provide possible approaches for the sensor fabrication in the future.

  3. Transforming Passive Receptivity of Knowledge into Deep Learning Experiences at the Undergraduate Level: An Example from Music Theory

    Science.gov (United States)

    Ferenc, Anna

    2015-01-01

    This article discusses transformation of passive knowledge receptivity into experiences of deep learning in a lecture-based music theory course at the second-year undergraduate level through implementation of collaborative projects that evoke natural critical learning environments. It presents an example of such a project, addresses key features…

  4. THE HEREDITARY STATUS OF DAUGHTERS ACCORDING TO THE COMMUNAL STATUTES OF PIRAN - RECEPTION OR CONTINUITY OF ROMAN LAW

    NARCIS (Netherlands)

    Kambic, Marko

    2010-01-01

    The reception of Roman law should be understood as a renewed and, in principle, subsidiary application of the Justinian's Codification as defined by methods of medieval and later on, modern legal science. The concept of continuity is, on the contrary, based on the notion that despite the fall of the

  5. Rapid core field variations during the satellite era: Investigations using stochastic process based field models

    DEFF Research Database (Denmark)

    Finlay, Chris; Olsen, Nils; Gillet, Nicolas

    . We report spherical harmonic spectra, comparisons to observatory monthly means, and maps of the radial field at the core-mantle boundary, from the resulting ensemble of core field models. We find that inter-annual fluctuations in the external field (for example related to high solar-driven activity...

  6. Gas identification field test based on FTIR imaging spectrometer

    Science.gov (United States)

    Wang, Chensheng; Liu, Xingchao; Zhang, Zhijie; Yu, Hui

    2017-10-01

    Gas detection and identification is based on the spectral absorption peak feature, which is acquired by the spectrometer. FTIR imaging spectrometer has the advantages of high spectral resolution and good sensitivity, which are both suitable for the unknown or mixture gas identification applications, such as plume pollution monitoring, chemical agents detection and leakage detection. According to the application requirement, a dual band FTIR imaging spectrometer has been developed and verified. This FTIR imaging spectrometer combines the infrared thermal imaging sensor and Michelson interferometer to form the three dimensional data cube. Based on this instrument, the theoretical analysis and algorithm is introduced, and the numerical method is explained to illuminate the basic idea in gas identification based on spectral features. After that, the field verification test is setup and completed. Firstly, the FTIR imaging spectrometer is used to detect SF6, NH3 and the mixture gas, while the gas is exhausted out from the storage vase with a specific speed. Secondly, the instrument is delivered to the industrial area to monitor the plume emission, and analyze the components in plume. Finally, the instrument is utilized to monitoring the oil spill in ocean, and the practical maritime trial is realized. Further, the gas concentration evaluation method is discussed. Quantitative issue in gas identification is an important topic. The test results show that, based on the gas identification method introduced in this paper, FTIR imaging spectrometer can be utilized to identify the unknown gas or mixture gas in real time. The instrument will play a key role in environmental emergency and monitoring application.

  7. Individual based and mean-field modeling of direct aggregation

    KAUST Repository

    Burger, Martin

    2013-10-01

    We introduce two models of biological aggregation, based on randomly moving particles with individual stochasticity depending on the perceived average population density in their neighborhood. In the firstorder model the location of each individual is subject to a density-dependent random walk, while in the second-order model the density-dependent random walk acts on the velocity variable, together with a density-dependent damping term. The main novelty of our models is that we do not assume any explicit aggregative force acting on the individuals; instead, aggregation is obtained exclusively by reducing the individual stochasticity in response to higher perceived density. We formally derive the corresponding mean-field limits, leading to nonlocal degenerate diffusions. Then, we carry out the mathematical analysis of the first-order model, in particular, we prove the existence of weak solutions and show that it allows for measure-valued steady states. We also perform linear stability analysis and identify conditions for pattern formation. Moreover, we discuss the role of the nonlocality for well-posedness of the first-order model. Finally, we present results of numerical simulations for both the first- and second-order model on the individual-based and continuum levels of description. 2012 Elsevier B.V. All rights reserved.

  8. Field-Based Validation of a Tactile Navigation Device.

    Science.gov (United States)

    Elliott, Linda R; van Erp, Jan B F; Redden, Elizabeth S; Duistermaat, Maaike

    2010-01-01

    In this paper, we present three field-based evaluations of a tactile land navigation system. In Experiment 1, we transition from a laboratory setting to rugged terrain used to train US Army soldier land navigation. Navigation in this challenging terrain requires careful attention to one's surroundings. Participants navigated 3 waypoints along 600 meters through heavily wooded terrain, using 1) map and compass, 2) standard alpha-numeric handheld GPS device, and 3) the tactile GPS system, while also responding to radio requests for information. Experiment 2 used the same challenging terrain during night operations, where participants must also search for live and silhouette targets, using 1) handheld GPS device, 2) head-mounted map-based GPS, and 3) the tactile GPS system. In addition to navigating, participants searched for silhouette and live (human) targets. Experiment 3 had participants navigate with 1) a commercial GPS arrow display, 2) the tactile GPS system, and 3) both together. We conclude that tactile navigation displays can be used in strenuous outdoor environments and can outperform visual displays under conditions of high cognitive and visual workload.

  9. Transmitter Architectures Based on Near-Field Direct Antenna Modulation

    OpenAIRE

    Babakhani, Aydin; Rutledge, David B.; Hajimiri, Ali

    2008-01-01

    A near-field direct antenna modulation (NFDAM) technique is introduced, where the radiated far-field signal is modulated by time-varying changes in the antenna near-field electromagnetic (EM) boundary conditions. This enables the transmitter to send data in a direction-dependent fashion producing a secure communication link. Near-field direct antenna modulation (NFDAM) can be performed by using either switches or varactors. Two fully-integrated proof-of-concept NFDAM transmitters operating at...

  10. Computer Based Training: Field Deployable Trainer and Shared Virtual Reality

    Science.gov (United States)

    Mullen, Terence J.

    1997-01-01

    Astronaut training has traditionally been conducted at specific sites with specialized facilities. Because of its size and nature the training equipment is generally not portable. Efforts are now under way to develop training tools that can be taken to remote locations, including into orbit. Two of these efforts are the Field Deployable Trainer and Shared Virtual Reality projects. Field Deployable Trainer NASA has used the recent shuttle mission by astronaut Shannon Lucid to the Russian space station, Mir, as an opportunity to develop and test a prototype of an on-orbit computer training system. A laptop computer with a customized user interface, a set of specially prepared CD's, and video tapes were taken to the Mir by Ms. Lucid. Based upon the feedback following the launch of the Lucid flight, our team prepared materials for the next Mir visitor. Astronaut John Blaha will fly on NASA/MIR Long Duration Mission 3, set to launch in mid September. He will take with him a customized hard disk drive and a package of compact disks containing training videos, references and maps. The FDT team continues to explore and develop new and innovative ways to conduct offsite astronaut training using personal computers. Shared Virtual Reality Training NASA's Space Flight Training Division has been investigating the use of virtual reality environments for astronaut training. Recent efforts have focused on activities requiring interaction by two or more people, called shared VR. Dr. Bowen Loftin, from the University of Houston, directs a virtual reality laboratory that conducts much of the NASA sponsored research. I worked on a project involving the development of a virtual environment that can be used to train astronauts and others to operate a science unit called a Biological Technology Facility (BTF). Facilities like this will be used to house and control microgravity experiments on the space station. It is hoped that astronauts and instructors will ultimately be able to share

  11. TLS FIELD DATA BASED INTENSITY CORRECTION FOR FOREST ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    J. Heinzel

    2016-06-01

    Full Text Available Terrestrial laser scanning (TLS is increasingly used for forestry applications. Besides the three dimensional point coordinates, the 'intensity' of the reflected signal plays an important role in forestry and vegetation studies. The benefit of the signal intensity is caused by the wavelength of the laser that is within the near infrared (NIR for most scanners. The NIR is highly indicative for various vegetation characteristics. However, the intensity as recorded by most terrestrial scanners is distorted by both external and scanner specific factors. Since details about system internal alteration of the signal are often unknown to the user, model driven approaches are impractical. On the other hand, existing data driven calibration procedures require laborious acquisition of separate reference datasets or areas of homogenous reflection characteristics from the field data. In order to fill this gap, the present study introduces an approach to correct unwanted intensity variations directly from the point cloud of the field data. The focus is on the variation over range and sensor specific distortions. Instead of an absolute calibration of the values, a relative correction within the dataset is sufficient for most forestry applications. Finally, a method similar to time series detrending is presented with the only pre-condition of a relative equal distribution of forest objects and materials over range. Our test data covers 50 terrestrial scans captured with a FARO Focus 3D S120 scanner using a laser wavelength of 905 nm. Practical tests demonstrate that our correction method removes range and scanner based alterations of the intensity.

  12. Receptive Learning Styles Of Introverts, Ambiverts And Extroverts In ...

    African Journals Online (AJOL)

    Learning to relate with people in their own style is important in helping to understand why they react the way they do. The purpose of this study therefore was to determine the differences in the receptive learning styles of introverts, ambiverts and extroverts in Senior High Schools (SHS) in the Sekondi-Takoradi Metropolis, ...

  13. The New ACRL Information Literacy Competency Standards: Revising Reception

    Directory of Open Access Journals (Sweden)

    Benjamin R. Harris

    2013-12-01

    Full Text Available The publication of educational standards inspires a variety of responses---from wholesale acceptance and deployment to criticism and blame. The author of this paper contends that the revision of the ACRL’s Information Literacy Competency Standards for Higher Education must be accompanied by a critical, conscious, and conscientious reception by librarians and information literacy advocates.

  14. The New ACRL Information Literacy Competency Standards: Revising Reception

    OpenAIRE

    Harris, Benjamin R.

    2013-01-01

    The publication of educational standards inspires a variety of responses---from wholesale acceptance and deployment to criticism and blame. The author of this paper contends that the revision of the ACRL’s Information Literacy Competency Standards for Higher Education must be accompanied by a critical, conscious, and conscientious reception by librarians and information literacy advocates.

  15. The Reception of Dewey in the Hispanic World

    Science.gov (United States)

    Nubiola, Jaime

    2005-01-01

    The aim of this paper is to describe Dewey's reception in the Spanish-speaking countries that constitute the Hispanic world. Without any doubt, it can be said that in the past century Spain and the countries of South America have been a world apart, lagging far behind the mainstream Western world. It includes a number of names and facts about the…

  16. Joint Book Reading and Receptive Vocabulary: A Parallel Process Model

    Science.gov (United States)

    Meng, Christine

    2016-01-01

    The purpose of the present study was to understand the reciprocal, bidirectional longitudinal relation between joint book reading and English receptive vocabulary. To address the research goals, a nationally representative sample of Head Start children, the Head Start Family and Child Experiences Survey (2003 cohort), was used for analysis. The…

  17. The Receptivity of Prospective University Candidates in Lagos ...

    African Journals Online (AJOL)

    , they were willing/not willing to utilise the distance learning mode to access university education. The analysis and tests of hypotheses focused strictly on receptivity to distance learning in relation to age group, gender, marital status, number of ...

  18. Intervention for Mixed Receptive-Expressive Language Impairment: A Review

    Science.gov (United States)

    Boyle, James; McCartney, Elspeth; O'Hare, Anne; Law, James

    2010-01-01

    Studies indicate that language impairment that cannot be accounted for by factors such as below-average non-verbal ability, hearing impairment, behaviour or emotional problems, or neurological impairments affects some 6% of school-age children. Language impairment with a receptive language component is more resistant to intervention than specific…

  19. [The Afrikaans receptive vocabulary test (ARV): description and psychometric evaluation].

    Science.gov (United States)

    Buitendag, M; Uys, I; Louw, B

    1991-01-01

    This article focuses on the psychometric characteristics of "Die Afrikaanse Reseptiewe Woordeskattoets (ARW)". The psychometric analysis indicates the test forms (A and B) to be equivalent, reliable and valid and that the ARW can thus be used with confidence as a screening and re-evaluation device for the evaluation of receptive vocabulary as well as intelligence.

  20. A New Receptive Vocabulary Size Test for French

    Science.gov (United States)

    Batista, Roselene; Horst, Marlise

    2016-01-01

    Researchers have developed several tests of receptive vocabulary knowledge suitable for use with learners of English, but options are few for learners of French. This situation motivated the authors to create a new vocabulary size measure for French, the "Test de la taille du vocabulaire" (TTV). The measure is closely modelled on…

  1. The Judaeo-Karaite Reception of the Hebrew Bible

    DEFF Research Database (Denmark)

    Sabih, Joshua

    and because it has been and still is considered peripheral and sectarian. This volume presents a critical edition of an anonymous Karaite commentary on the Book of Jeremiah presented in both the original Arabic and in English translation. The volume uses this text to examine the commonalities and differences...... between the Rabbinate and the Karaite reception and interpretation of the Hebrew Bible....

  2. Surges and sediments: shaping the reception of reengineering

    NARCIS (Netherlands)

    Heusinkveld, H.S.; Benders, J.G.J.M.

    2001-01-01

    The business community is continuously confronted with allegedly new concepts. These are often temporarily intensely advocated, yet are at the same time likely to be portrayed as transitory or ‘faddish’ phenomena. To trace the reception of these concepts, this paper examines the Dutch discourse on

  3. Psychological models of art reception must be empirically grounded

    DEFF Research Database (Denmark)

    Nadal, Marcos; Vartanian, Oshin; Skov, Martin

    2018-01-01

    We commend Menninghaus et al. for tackling the role of negative emotions in art reception. However, their model suffers from shortcomings that reduce its applicability to empirical studies of the arts: poor use of evidence, lack of integration with other models, and limited derivation of testable...

  4. Ovarian fluid of receptive females enhances sperm velocity

    Science.gov (United States)

    Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea

    2012-05-01

    The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy ( Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites.

  5. Real gas effects on receptivity to kinetic fluctuations

    Science.gov (United States)

    Tumin, Anatoli; Edwards, Luke

    2016-11-01

    Receptivity of high-speed boundary layers is considered within the framework of fluctuating hydrodynamics where stochastic forcing is introduced through fluctuating shear stress and heat flux stemming from kinetic fluctuations (thermal noise). The forcing generates unstable modes whose amplification downstream and may lead to transition. An example of high-enthalpy (16 . 53 MJ / kg) boundary layer at relatively low wall temperatures (Tw = 1000 K - 3000 K), free stream temperature (Te = 834 K), and low pressure (0 . 0433 atm) is considered. Dissociation at the chosen flow parameters is still insignificant. The stability and receptivity analyses are carried out using a solver for calorically perfect gas with effective Prandtl number and specific heats ratio. The receptivity phenomenon is unchanged by the inclusion of real gas effects in the mean flow profiles. This is attributed to the fact that the mechanism for receptivity to kinetic fluctuations is localized near the upper edge of the boundary layer. Amplitudes of the generated wave packets are larger downstream in the case including real gas effects. It was found that spectra in both cases include supersonic second Mack unstable modes despite the temperature ratio Tw /Te > 1 . Supported by AFOSR.

  6. Field-Based Experiential Learning Using Mobile Devices

    Science.gov (United States)

    Hilley, G. E.

    2015-12-01

    Technologies such as GPS and cellular triangulation allow location-specific content to be delivered by mobile devices, but no mechanism currently exists to associate content shared between locations in a way that guarantees the delivery of coherent and non-redundant information at every location. Thus, experiential learning via mobile devices must currently take place along a predefined path, as in the case of a self-guided tour. I developed a mobile-device-based system that allows a person to move through a space along a path of their choosing, while receiving information in a way that guarantees delivery of appropriate background and location-specific information without producing redundancy of content between locations. This is accomplished by coupling content to knowledge-concept tags that are noted as fulfilled when users take prescribed actions. Similarly, the presentation of the content is related to the fulfillment of these knowledge-concept tags through logic statements that control the presentation. Content delivery is triggered by mobile-device geolocation including GPS/cellular navigation, and sensing of low-power Bluetooth proximity beacons. Together, these features implement a process that guarantees a coherent, non-redundant educational experience throughout a space, regardless of a learner's chosen path. The app that runs on the mobile device works in tandem with a server-side database and file-serving system that can be configured through a web-based GUI, and so content creators can easily populate and configure content with the system. Once the database has been updated, the new content is immediately available to the mobile devices when they arrive at the location at which content is required. Such a system serves as a platform for the development of field-based geoscience educational experiences, in which students can organically learn about core concepts at particular locations while individually exploring a space.

  7. Leakage magnetic field of BLDCM based on Comsol multiphysics

    Science.gov (United States)

    Zhang, Xiaojun; Wen, Jiabao; Wang, Wen; Sun, Jinghua

    2017-04-01

    The measurement of geomagnetic field conducted by underwater robot is widely used during cruise, however, it is often influenced by the strong electromagnetic interference of the other large-scale electronic equipment on the robot itself. The leakage magnetic field of high-power brushless DC motor (BLDCM) has been identified as one of the main interference source. To obtain accurate geomagnetic data, it is necessary to analyze the magnetic field characteristics of the leakage field of BLDCM. In this paper, we build a two-dimensional BLDCM model. In addition, we present the rotor's leakage magnetic field when the BLDCM is static, dynamic leakage magnetic field of the stator and rotor when BLDCM is working and the near-field characteristic of BLDCM's leakage magnetic field. Finally, this paper studies the relationship between the frequency of the magnetic field change and the speed of the BLDCM, which can be used to eliminate the AC interference magnetic field. Therefore the measuring accuracy of the geomagnetic field can be improved.

  8. Design Guidance for Computer-Based Procedures for Field Workers

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States); Le Blanc, Katya [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bly, Aaron [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Nearly all activities that involve human interaction with nuclear power plant systems are guided by procedures, instructions, or checklists. Paper-based procedures (PBPs) currently used by most utilities have a demonstrated history of ensuring safety; however, improving procedure use could yield significant savings in increased efficiency, as well as improved safety through human performance gains. The nuclear industry is constantly trying to find ways to decrease human error rates, especially human error rates associated with procedure use. As a step toward the goal of improving field workers’ procedure use and adherence and hence improve human performance and overall system reliability, the U.S. Department of Energy Light Water Reactor Sustainability (LWRS) Program researchers, together with the nuclear industry, have been investigating the possibility and feasibility of replacing current paper-based procedures with computer-based procedures (CBPs). PBPs have ensured safe operation of plants for decades, but limitations in paper-based systems do not allow them to reach the full potential for procedures to prevent human errors. The environment in a nuclear power plant is constantly changing, depending on current plant status and operating mode. PBPs, which are static by nature, are being applied to a constantly changing context. This constraint often results in PBPs that are written in a manner that is intended to cover many potential operating scenarios. Hence, the procedure layout forces the operator to search through a large amount of irrelevant information to locate the pieces of information relevant for the task and situation at hand, which has potential consequences of taking up valuable time when operators must be responding to the situation, and potentially leading operators down an incorrect response path. Other challenges related to use of PBPs are management of multiple procedures, place-keeping, finding the correct procedure for a task, and relying

  9. Health Challenges in Refugee Reception: Dateline Europe 2016

    Directory of Open Access Journals (Sweden)

    Brad K. Blitz

    2017-11-01

    Full Text Available The arrival of more than one million migrants, many of them refugees, has proved a major test for the European Union. Although international relief and monitoring agencies have been critical of makeshift camps in Calais and Eidomeni where infectious disease and overcrowding present major health risks, few have examined the nature of the official reception system and its impact on health delivery. Drawing upon research findings from an Economic and Social Research Council (ESRC funded project, this article considers the physical and mental health of asylum–seekers in transit and analyses how the closure of borders has engendered health risks for populations in recognised reception centres in Sicily and in Greece. Data gathered by means of a survey administered in Greece (300 and in Sicily (400, and complemented by in-depth interviews with migrants (45 and key informants (50 including representatives of government offices, humanitarian and relief agencies, NGOs and activist organisations, are presented to offer an analysis of the reception systems in the two frontline states. We note that medical provision varies significantly from one centre to another and that centre managers play a critical role in the transmission of vital information. A key finding is that, given such disparity, the criteria used by the UNHCR to grade health services reception do not address the substantive issue that prevent refugees from accessing health services, even when provided on site. Health provision is not as recorded in UNHCR reporting but rather there are critical gaps between provision, awareness, and access for refugees in reception systems in Sicily and in Greece. This article concludes that there is a great need for more information campaigns to direct refugees to essential services.

  10. Vector optical field generation based on birefringent phase plate.

    Science.gov (United States)

    Wang, Jiazhou; Cao, Axiu; Pang, Hui; Zhang, Man; Wang, Guangyi; Chen, Jian; Shi, Lifang; Deng, Qiling; Hu, Song

    2017-05-29

    Vector optical field has recently gained interest in a variety of application fields due to its novel characteristics. Conventional approaches of generating vector optical fields have difficulties in forming highly continuous polarization and suffer from the issue of high energy utilization rates. In order to address these issues, in this study a single optical path was proposed to generate vector optical fields where the birefringent phase plate modulated a linear polarized light into a vector optical field, which was then demodulated to a non-uniform linear polarization distribution of the vector optical field by the polarization demodulation module. Both a theoretical model and numerical simulations of the vector optical field generator were developed, illustrating the relationship between the polarization distribution of the target vector optical field and the depth distribution of the birefringent phase plate. Furthermore, the birefringent phase plate with predefined surface distributions was fabricated by grayscale exposure and ion etching. The generated vector optical field was experimentally characterized, capable of producing continuous polarization with high light energy utilization ratio, consistent with simulations. This new approach may have the potential of being widely used in future studies of generating well-controlled vector optical fields.

  11. Rocket to Creativity: A Field Experience in Problem-Based and Project-Based Learning

    Directory of Open Access Journals (Sweden)

    Sharon F. Dole

    2016-11-01

    Full Text Available The purpose of this article is to examine the impact of a field experience in problem-based (PBL and project-based learning (PjBL on pre-service and in-service teachers’ conceptions of experiential learning. In our study, participants had been enrolled in a hybrid class that included an online component in which they learned about PBL and PjBL and an experiential component in which they facilitated PBL and PjBL with children in grades 1-9 during a one-week field experience on a university campus. The goal of the field experience is for teachers to change their practice from didactic to inquiry and to promote critical and creative thinking in their students. We used a case study method that involved data derived from six different sources: online structured interviews, follow-up telephone interviews, discussion board posts, reflections, course feedback, and observations. The main theme that emerged from the data analysis was the critical role the field experience played in applying theory to practice. Sub-themes included understanding the process of implementing PBL and PjBL, mastering the logistics of PBL and PjBL, becoming facilitators, and collaborating with partners. Results showed that the field experience gave the teachers the “courage” to experiment with a student-centered methodology.

  12. Near Field Communication-based telemonitoring with integrated ECG recordings.

    Science.gov (United States)

    Morak, J; Kumpusch, H; Hayn, D; Leitner, M; Scherr, D; Fruhwald, F M; Schreier, G

    2011-01-01

    Telemonitoring of vital signs is an established option in treatment of patients with chronic heart failure (CHF). In order to allow for early detection of atrial fibrillation (AF) which is highly prevalent in the CHF population telemonitoring programs should include electrocardiogram (ECG) signals. It was therefore the aim to extend our current home monitoring system based on mobile phones and Near Field Communication technology (NFC) to enable patients acquiring their ECG signals autonomously in an easy-to-use way. We prototypically developed a sensing device for the concurrent acquisition of blood pressure and ECG signals. The design of the device equipped with NFC technology and Bluetooth allowed for intuitive interaction with a mobile phone based patient terminal. This ECG monitoring system was evaluated in the course of a clinical pilot trial to assess the system's technical feasibility, usability and patient's adherence to twice daily usage. 21 patients (4f, 54 ± 14 years) suffering from CHF were included in the study and were asked to transmit two ECG recordings per day via the telemonitoring system autonomously over a monitoring period of seven days. One patient dropped out from the study. 211 data sets were transmitted over a cumulative monitoring period of 140 days (overall adherence rate 82.2%). 55% and 8% of the transmitted ECG signals were sufficient for ventricular and atrial rhythm assessment, respectively. Although ECG signal quality has to be improved for better AF detection the developed communication design of joining Bluetooth and NFC technology in our telemonitoring system allows for ambulatory ECG acquisition with high adherence rates and system usability in heart failure patients.

  13. Ultraviolet refractometry using field-based light scattering spectroscopy

    Science.gov (United States)

    Fu, Dan; Choi, Wonshik; Sung, Yongjin; Oh, Seungeun; Yaqoob, Zahid; Park, YongKeun; Dasari, Ramachandra R.; Feld, Michael S.

    2010-01-01

    Accurate refractive index measurement in the deep ultraviolet (UV) range is important for the separate quantification of biomolecules such as proteins and DNA in biology. This task is demanding and has not been fully exploited so far. Here we report a new method of measuring refractive index using field-based light scattering spectroscopy, which is applicable to any wavelength range and suitable for both solutions and homogenous objects with well-defined shape such as microspheres. The angular scattering distribution of single microspheres immersed in homogeneous media is measured over the wavelength range 260 to 315 nm using quantitative phase microscopy. By least square fitting the observed scattering distribution with Mie scattering theory, the refractive index of either the sphere or the immersion medium can be determined provided that one is known a priori. Using this method, we have measured the refractive index dispersion of SiO2 spheres and bovine serum albumin (BSA) solutions in the deep UV region. Specific refractive index increments of BSA are also extracted. Typical accuracy of the present refractive index technique is ≤0.003. The precision of refractive index measurements is ≤0.002 and that of specific refractive index increment determination is ≤0.01 mL/g. PMID:20372622

  14. Statistics-Based Compression of Global Wind Fields

    KAUST Repository

    Jeong, Jaehong

    2017-02-07

    Wind has the potential to make a significant contribution to future energy resources. Locating the sources of this renewable energy on a global scale is however extremely challenging, given the difficulty to store very large data sets generated by modern computer models. We propose a statistical model that aims at reproducing the data-generating mechanism of an ensemble of runs via a Stochastic Generator (SG) of global annual wind data. We introduce an evolutionary spectrum approach with spatially varying parameters based on large-scale geographical descriptors such as altitude to better account for different regimes across the Earth\\'s orography. We consider a multi-step conditional likelihood approach to estimate the parameters that explicitly accounts for nonstationary features while also balancing memory storage and distributed computation. We apply the proposed model to more than 18 million points of yearly global wind speed. The proposed SG requires orders of magnitude less storage for generating surrogate ensemble members from wind than does creating additional wind fields from the climate model, even if an effective lossy data compression algorithm is applied to the simulation output.

  15. Germanium Based Field-Effect Transistors: Challenges and Opportunities

    Directory of Open Access Journals (Sweden)

    Patrick S. Goley

    2014-03-01

    Full Text Available The performance of strained silicon (Si as the channel material for today’s metal-oxide-semiconductor field-effect transistors may be reaching a plateau. New channel materials with high carrier mobility are being investigated as alternatives and have the potential to unlock an era of ultra-low-power and high-speed microelectronic devices. Chief among these new materials is germanium (Ge. This work reviews the two major remaining challenges that Ge based devices must overcome if they are to replace Si as the channel material, namely, heterogeneous integration of Ge on Si substrates, and developing a suitable gate stack. Next, Ge is compared to compound III-V materials in terms of p-channel device performance to review how it became the first choice for PMOS devices. Different Ge device architectures, including surface channel and quantum well configurations, are reviewed. Finally, state-of-the-art Ge device results and future prospects are also discussed.

  16. Applied Epistemology and Professional Training in a Science-Based Cultural Enterprise

    Science.gov (United States)

    Hoshmand; Lisa Tsoi

    2003-01-01

    Receptiveness toward evidence-based practice such as proposed by Chwalisz (2003) (this issue) is a function of how one defines the discipline and how one views counseling and psychotherapy. By acknowledging the dual nature of therapeutic psychology as a science-based cultural enterprise, one may be able to overcome schisms in the field and related…

  17. The reception of Bollywood in Malaysia (1991-2012): a contextual study

    OpenAIRE

    Rohini SREEKUMAR

    2017-01-01

    Bollywood films are increasingly drawing scholarly attention for their global appeal and reception. Transnational studies have examined the reception of Bollywood in Australia, Britain, Scotland, South Africa, Russia, the United States of America, Bangladesh and Nepal. However, academic work on the Southeast Asian reception of these films is scarcer. This research seeks to fill this gap by looking at the reception of Bollywood in Malaysia from 1991-2012. The thesis adopts a...

  18. Age Differences in the Reception of New Scientific Theories: The Case of Plate Tectonics Theory.

    Science.gov (United States)

    Messeri, Peter

    1988-01-01

    Reviews various evidences on the relationship between age and the reception of major innovations in science. Examines the possibility that age patterning of reception may vary over time. Reports the potential importance of age on the reception of ideas while rejecting the presumption that advanced age leads to increased resistance. (YP)

  19. Receptive and Expressive Language Skills in Children with Cri-du-Chat Syndrome.

    Science.gov (United States)

    Cornish, K. M.; Munir, F.

    1998-01-01

    Receptive and expressive language skills were assessed in 13 British children (ages 4-14) with cri-du-chat syndrome. Results found a discrepancy between the children's chronological ages and their presumed language ages and a receptive-expressive discrepancy, with reduced expressive skills compared to receptive skills. Remediation that focuses on…

  20. Deaf Students' Receptive and Expressive American Sign Language Skills: Comparisons and Relations

    Science.gov (United States)

    Beal-Alvarez, Jennifer S.

    2014-01-01

    This article presents receptive and expressive American Sign Language skills of 85 students, 6 through 22 years of age at a residential school for the deaf using the American Sign Language Receptive Skills Test and the Ozcaliskan Motion Stimuli. Results are presented by ages and indicate that students' receptive skills increased with age and…

  1. Field-based study of connectivity in an agricultural catchment

    Science.gov (United States)

    Lexartza-Artza, I.; Wainwright, J.

    2009-12-01

    Field-based studies of hydrological connectivity can provide context-specific knowledge that might both help understand dynamic complex systems and contribute to other synthetic or modelling approaches. The importance of such an understanding of catchment processes and also of the knowledge of catchment connections with water bodies and the changes of concentration with scale for Integrated Catchment Management has been increasingly emphasized. To provide a holistic understanding, approaches to the study of connectivity need to include both structural and functional aspects of the system and must consider the processes taking place within and across different temporal and spatial scales. A semi-quantitative nested approach has been used to investigate connectivity and study the interactions and feedbacks between the factors influencing transfer processes in the Ingbirchworth Catchment, in the uplands of the River Don, England. A series of reconnaissance techniques have been combined with monitoring of aspects such as rainfall, runoff, sediment transfer and soil-moisture distribution from plot to catchment scale and with consideration of linkages between land and water bodies. The temporal aspect has also been considered, with a special focus on the temporal distribution of events and the influence of longer term catchment changes such as those in land use and management practices. A variability of responses has been observed in relation to the characteristics of events, land use and scale of observation, with elements traditionally considered as limiting or enhancing connectivity responding differently under changing conditions. Sediment redistribution, reshaping of structure and consequent reinforcing loops can be observed across all land uses and landscape units, but the relevance it terms of effective connectivity of highly connected patches varies as the scale is increased. The knowledge acquired can contribute to recognise emerging processes significant for

  2. Bearing Fault Classification Based on Conditional Random Field

    Directory of Open Access Journals (Sweden)

    Guofeng Wang

    2013-01-01

    Full Text Available Condition monitoring of rolling element bearing is paramount for predicting the lifetime and performing effective maintenance of the mechanical equipment. To overcome the drawbacks of the hidden Markov model (HMM and improve the diagnosis accuracy, conditional random field (CRF model based classifier is proposed. In this model, the feature vectors sequences and the fault categories are linked by an undirected graphical model in which their relationship is represented by a global conditional probability distribution. In comparison with the HMM, the main advantage of the CRF model is that it can depict the temporal dynamic information between the observation sequences and state sequences without assuming the independence of the input feature vectors. Therefore, the interrelationship between the adjacent observation vectors can also be depicted and integrated into the model, which makes the classifier more robust and accurate than the HMM. To evaluate the effectiveness of the proposed method, four kinds of bearing vibration signals which correspond to normal, inner race pit, outer race pit and roller pit respectively are collected from the test rig. And the CRF and HMM models are built respectively to perform fault classification by taking the sub band energy features of wavelet packet decomposition (WPD as the observation sequences. Moreover, K-fold cross validation method is adopted to improve the evaluation accuracy of the classifier. The analysis and comparison under different fold times show that the accuracy rate of classification using the CRF model is higher than the HMM. This method brings some new lights on the accurate classification of the bearing faults.

  3. Semantic Web-based digital, field and virtual geological

    Science.gov (United States)

    Babaie, H. A.

    2012-12-01

    Digital, field and virtual Semantic Web-based education (SWBE) of geological mapping requires the construction of a set of searchable, reusable, and interoperable digital learning objects (LO) for learners, teachers, and authors. These self-contained units of learning may be text, image, or audio, describing, for example, how to calculate the true dip of a layer from two structural contours or find the apparent dip along a line of section. A collection of multi-media LOs can be integrated, through domain and task ontologies, with mapping-related learning activities and Web services, for example, to search for the description of lithostratigraphic units in an area, or plotting orientation data on stereonet. Domain ontologies (e.g., GeologicStructure, Lithostratigraphy, Rock) represent knowledge in formal languages (RDF, OWL) by explicitly specifying concepts, relations, and theories involved in geological mapping. These ontologies are used by task ontologies that formalize the semantics of computational tasks (e.g., measuring the true thickness of a formation) and activities (e.g., construction of cross section) for all actors to solve specific problems (making map, instruction, learning support, authoring). A SWBE system for geological mapping should also involve ontologies to formalize teaching strategy (pedagogical styles), learner model (e.g., for student performance, personalization of learning), interface (entry points for activities of all actors), communication (exchange of messages among different components and actors), and educational Web services (for interoperability). In this ontology-based environment, actors interact with the LOs through educational servers, that manage (reuse, edit, delete, store) ontologies, and through tools which communicate with Web services to collect resources and links to other tools. Digital geological mapping involves a location-based, spatial organization of geological elements in a set of GIS thematic layers. Each layer

  4. A "Medical Physics" Course Based Upon Hospital Field Experience

    Science.gov (United States)

    Onn, David G.

    1972-01-01

    Describes a noncalculus, medical physics'' course with a basic element of direct hospital field experience. The course is intended primarily for premedical students but may be taken by nonscience majors. (Author/PR)

  5. Temperature Field-Wind Velocity Field Optimum Control of Greenhouse Environment Based on CFD Model

    Directory of Open Access Journals (Sweden)

    Yongbo Li

    2014-01-01

    Full Text Available The computational fluid dynamics technology is applied as the environmental control model, which can include the greenhouse space. Basic environmental factors are set to be the control objects, the field information is achieved via the division of layers by height, and numerical characteristics of each layer are used to describe the field information. Under the natural ventilation condition, real-time requirements, energy consumption, and distribution difference are selected as index functions. The optimization algorithm of adaptive simulated annealing is used to obtain optimal control outputs. A comparison with full-open ventilation shows that the whole index can be reduced at 44.21% and found that a certain mutual exclusiveness exists between the temperature and velocity field in the optimal course. All the results indicate that the application of CFD model has great advantages to improve the control accuracy of greenhouse.

  6. Prediction of Cycle 25 based on Polar Fields

    Science.gov (United States)

    Svalgaard, Leif; Sun, Xudong; Bobra, Monica

    2016-10-01

    WSO: The pole-most aperture measures the lineof-sight field between about 55° and the poles. Each 10 days the usable daily polar field measurements in a centered 30-day window are averaged. A 20nHz low pass filter eliminates yearly geometric projection effects. SDO-HMI: Line-of-sight magnetic observations (Blos above 60° lat.) at 720s cadence are converted to radial field (Br), under the assumption that the actual field vector is radial. Twice-per-day values are calculated as the mean weighted by de-projected image pixel areas for each latitudinal bin within ±45-deg longitude. These raw (12-hour) data have been averaged into the same windows as WSO's and reduced to the WSO scale taking saturation (1.8) and projection (COS(72°)) into account. We have argued that the 'poloidal' field in the years leading up to solar minimum is a good proxy for the size of the next cycle (SNmax≈ DM [WSO scale μT]). The successful prediction of Cycle 24 seems to bear that out, as well as the observed corroboration from previous cycles. As a measure of the poloidal field we used the average 'Dipole Moment', i.e. the difference, DM, between the fields at the North pole and the South pole. The 20nHz filtered WSO DM matches well the HMI DM on the WSO scale using the same 30-day window as WSO. So, we can extend WSO using HMI into the future as needed. Preliminarily, the polar fields now are as strong as before the last minimum and may increase further, so Cycle 25 may be at least a repeat of Cycle 24, not any smaller and possible a bit stronger.

  7. Electric field calculations in brain stimulation based on finite elements

    DEFF Research Database (Denmark)

    Windhoff, Mirko; Opitz, Alexander; Thielscher, Axel

    2013-01-01

    The need for realistic electric field calculations in human noninvasive brain stimulation is undisputed to more accurately determine the affected brain areas. However, using numerical techniques such as the finite element method (FEM) is methodologically complex, starting with the creation...... elements. The latter is crucial to guarantee the numerical robustness of the FEM calculations. The pipeline will be released as open-source, allowing for the first time to perform realistic field calculations at an acceptable methodological complexity and moderate costs....

  8. Receptive vocabulary knowledge and motivation in CLIL and EFL

    Directory of Open Access Journals (Sweden)

    Almudena Fernández Fontecha

    2014-05-01

    Full Text Available Content and Language Integrated Learning (CLIL is a widely researched approach to foreign language learning and teaching. One of the pillars of CLIL is the concept of motivation. Some studies have focused on exploring motivation within CLIL, however there has not been much discussion about the connection between motivation, or other affective factors, and each component of foreign language learning. Hence, given two groups of learners with the same hours of EFL instruction, the main objective of this research is to determine whether there exists any kind of interaction between the number of words learners know receptively and their motivation towards English as a Foreign Language (EFL. Most students in both groups were highly motivated. No relationship was identified between the receptive vocabulary knowledge and the general motivation for the secondary graders but a positive significant relationship was found for the primary CLIL graders. Several reasons will be adduced.

  9. The Comparative Reception of Darwinism: A Brief History

    Science.gov (United States)

    Glick, Thomas F.

    2010-06-01

    The subfield of Darwin studies devoted to comparative reception coalesced around 1971 with the planning of a conference on the subject, at the University of Texas at Austin held in April 1972. The original focus was western Europe, Russia and the United States. Subsequently a spate of studies on the Italian reception added to the Eurocentric focus. The center of activity then switched to Latin America where a group of scholars coalesced in the mid 1990s, seemingly related to the maturation of the history of science as a discrete discipline there somewhat earlier. When interest in Europe revived during the last decade, the center of gravity had moved both eastward, to the former Society bloc countries (a reflection of the institutionalization of the history of science there), and north to Scandinavia. Recently, interest in the topic has emerged in the Islamic World. The subtext of the expansion of this topic is modernization.

  10. Reception of Jovan Cvijić in Slovenian ethnology

    Directory of Open Access Journals (Sweden)

    Slavec-Gradišnik Ingrid

    2016-01-01

    Full Text Available The paper discusses the reception of the work of Jovan Cvijić in Slovenian ethnology. Cvijić is considered to be one of the founding fathers of Serbian ethnology, due in large part to his anthropogeographical orientation that strongly marked ethnological research in Serbia until the second half of the 20th century. In Slovenian ethnology, the so-called anthropogeographical school is virtually unknown; however, some of its tenets can be recognized or were actively applied in research of cultural areas, carried out by geographers and ethnographers before and after the Second World War when anthropogeography was considered to be a branch of geography and a discipline akin to ethnography/ethnology. The author aims to discuss when, for whom and in what way was Jovan Cvijić direct or indirect reference within the horizon of Slovenian ethnology. His reception is marked by acknowledging the powerful influence of his political views and engagement on his scholarship.

  11. Pancreatic cancer study based on full field OCT and dynamic full field OCT (Conference Presentation)

    Science.gov (United States)

    Apelian, Clement; Camus, Marine; Prat, Frederic; Boccara, A. Claude

    2017-02-01

    Pancreatic cancer is one of the most feared cancer types due to high death rates and the difficulty to perform surgery. This cancer outcome could benefit from recent technological developments for diagnosis. We used a combination of standard Full Field OCT and Dynamic Full Field OCT to capture both morphological features and metabolic functions of rodents pancreas in normal and cancerous conditions with and without chemotherapy. Results were compared to histology to evaluate the performances and the specificities of the method. The comparison highlighted the importance of a number of endogenous markers like immune cells, fibrous development, architecture and more.

  12. Impaired receptivity and decidualization in DHEA-induced PCOS mice

    OpenAIRE

    Li, Shu-Yun; Song, Zhuo; Song, Min-Jie; Qin, Jia-Wen; Zhao, Meng-Long; Yang, Zeng-Ming

    2016-01-01

    Polycystic ovary syndrome (PCOS), a complex endocrine disorder, is a leading cause of female infertility. An obvious reason for infertility in PCOS women is anovulation. However, success rate with high quality embryos selected by assisted reproduction techniques in PCOS patients still remain low with a high rate of early clinical pregnancy loss, suggesting a problem in uterine receptivity. Using a dehydroepiandrosterone-induced mouse model of PCOS, some potential causes of decreased fertility...

  13. Understanding receptivity to interruptions in mobile human-computer interaction

    OpenAIRE

    Fischer, Joel,

    2011-01-01

    Interruptions have a profound impact on our attentional orientation in everyday life. Recent advances in mobile information technology increase the number of potentially disruptive notifications on mobile devices by an increasing availability of services. Understanding the contextual intricacies that make us receptive to these interruptions is paramount to devising technology that supports interruption management. This thesis makes a number of contributions to the methodology of studying ...

  14. K-pop Reception and Participatory Fan Culture in Austria

    Directory of Open Access Journals (Sweden)

    Sang-Yeon Sung

    2013-12-01

    Full Text Available K-pop’s popularity and its participatory fan culture have expanded beyond Asia and become significant in Europe in the past few years. After South Korean pop singer Psy’s “Gangnam Style” music video topped the Austrian chart in October 2012, the number and size of K-pop events in Austria sharply increased, with fans organizing various participatory events, including K-pop auditions, dance festivals, club meetings, quiz competitions, dance workshops, and smaller fan-culture gatherings. In the private sector, longtime fans have transitioned from participants to providers, and in the public sector, from observers to sponsors. Through in-depth interviews with event organizers, sponsors, and fans, this article offers an ethnographic study of the reception of K-pop in Europe that takes into consideration local interactions between fans and Korean sponsors, perspectives on the genre, patterns of social integration, and histories. As a case study, this research stresses the local situatedness of K-pop fan culture by arguing that local private and public sponsors and fans make the reception of K-pop different in each locality. By exploring local scenes of K-pop reception and fan culture, the article demonstrates the rapidly growing consumption of K-pop among Europeans and stresses multidirectional understandings of globalization.

  15. Application of receptive music therapy in internal medicine and cardiology

    Directory of Open Access Journals (Sweden)

    Cyntia Marconato

    2001-08-01

    Full Text Available OBJECTIVE: To investigate the effects of receptive music therapy in clinical practice. METHODS: Receptive music therapy was individually applied via musical auditions, including five stages: musical stimulation, sensation, situation, reflection, and behavioral alteration. Following anamnesis and obtainment of consent, patients answered a first questionnaire on health risk evaluation (Q1, and after participating in 16 weekly music therapy sessions, answered a second one (Q2. RESULTS: Two men and 8 women, aged above 18 years, referred to us due to symptoms of stress, emotional suffering, and the need to change lifestyles (health risk behavior were studied between August 1998 and December 1999. Comparison between answers to Q1 and Q2, showed a trend (P=0.059 for reduction of ingestion of cholesterol-rich foods and for increased prospects in life with a tendency towards improvement, and also of increased intake of fiber-rich food (55.6%, increased levels of personal satisfaction (44.5%, and decreased levels of stress (66.7%. CONCLUSION: The study demonstrated decreased stress levels and increased personal satisfaction, higher consumption of fiber-rich food, lower cholesterol intake, and a better perspective on life, suggesting that receptive music therapy may be applied in clinical practice as an auxiliary therapeutic intervention for the treatment of behavioral health risks.

  16. Clinical investigations of receptive and expressive musical functions after stroke.

    Science.gov (United States)

    Rosslau, Ken; Steinwede, Daniel; Schröder, C; Herholz, Sibylle C; Lappe, Claudia; Dobel, Christian; Altenmüller, Eckart

    2015-01-01

    There is a long tradition of investigating various disorders of musical abilities after stroke. These impairments, associated with acquired amusia, can be highly selective, affecting only music perception (i.e., receptive abilities/functions) or expression (music production abilities), and some patients report that these may dramatically influence their emotional state. The aim of this study was to systematically test both the melodic and rhythmic domains of music perception and expression in left- and right-sided stroke patients compared to healthy subjects. Music perception was assessed using rhythmic and melodic discrimination tasks, while tests of expressive function involved the vocal or instrumental reproduction of rhythms and melodies. Our approach revealed deficits in receptive and expressive functions in stroke patients, mediated by musical expertise. Those patients who had experienced a short period of musical training in childhood and adolescence performed better in the receptive and expressive subtests compared to those without any previous musical training. While discrimination of specific musical patterns was unimpaired after a left-sided stroke, patients with a right-sided stroke had worse results for fine melodic and rhythmic analysis. In terms of expressive testing, the most consistent results were obtained from a test that required patients to reproduce sung melodies. This implies that the means of investigating production abilities can impact the identification of deficits.

  17. Aesthetic-Receptive and Critical-Creative in Appreciative Reading

    Directory of Open Access Journals (Sweden)

    Titin Setiartin

    2017-10-01

    Full Text Available Reading is a process of aesthetically appreciative receptive to emphasize critical-creative reading activities. Metacognitively students understand, address any and explore the idea of the author in the text. Students responded, criticize, and evaluate the author's ideas in the text. At this stage, students can construct their post read text into other forms (new text. The aim of this strategy equips students to understand the meaning of the story, explore ideas, responding critically, and creatively pouring backstory idea. Reading strategies aesthetically-critical-creative receptive grabbed cognitive, effective, and psychomotor toward literacy critical reading and creative writing. Read appreciative included into the activities of reading comprehension. This activity involves the sensitivity and ability to process aesthetically-receptive reading and critical-creative. Readers imagination roam the author to obtain meaningful understanding and experience of reading. Some models of reading comprehension proposed experts covering the steps before reading, when reading, and after reading. At that stage to enable students after reading thinking abilities. Activities that can be done at this stage, for example, examine the back story, retell, make drawings, diagrams, or maps the concept of reading, as well as making a road map that describes the event. Other activities that can be done is to transform our student's text stories through reinforcement form illustrated stories into comic book form, for example (transliteration.

  18. College Student Receptiveness to Various Alcohol Treatment Options

    Science.gov (United States)

    Epler, Amee J.; Sher, Kenneth J.; Loomis, Tiffany B.; O'Malley, Stephanie S.

    2009-01-01

    Objective Heavy episodic drinking remains a significant problem on college campuses. Although most interventions for college students are behavioral, pharmacological treatments, such as naltrexone, could provide additional options. Participants The authors evaluated receptivity to various alcohol treatment options in a general population of college student drinkers (N = 2,084), assessed in 2005. Methods The authors asked participants to indicate which of 8 treatment options (ie, sell-help book, self-help computer program, self-help group, group therapy, individual therapy, monthly injection, targeted oral medication, or daily oral medication) they would be willing to consider if they were going to cut down on or stop drinking. Results Over 50% of drinkers expressed receptiveness to self-help options or psychotherapy options, and over 25% of drinkers expressed receptiveness to medication options. Conclusions Increasing treatment options for students interested in reducing or stopping drinking by offering pharmacological interventions such as naltrexone could provide an important unmet need among college students. PMID:19592350

  19. The relevance of receptive vocabulary in reading comprehension.

    Science.gov (United States)

    Nalom, Ana Flávia de Oliveira; Soares, Aparecido José Couto; Cárnio, Maria Silvia

    2015-01-01

    To characterize the performance of students from the 5th year of primary school, with and without indicatives of reading and writing disorders, in receptive vocabulary and reading comprehension of sentences and texts, and to verify possible correlations between both. This study was approved by the Research Ethics Committee of the institution (no. 098/13). Fifty-two students in the 5th year from primary school, with and without indicatives of reading and writing disorders, and from two public schools participated in this study. After signing the informed consent and having a speech therapy assessment for the application of inclusion criteria, the students were submitted to a specific test for standardized evaluation of receptive vocabulary and reading comprehension. The data were studied using statistical analysis through the Kruskal-Wallis test, analysis of variance techniques, and Spearman's rank correlation coefficient with level of significance to be 0.05. A receiver operating characteristic (ROC) curve (was constructed in which reading comprehension was considered as gold standard. The students without indicatives of reading and writing disorders presented a better performance in all tests. No significant correlation was found between the tests that evaluated reading comprehension in either group. A correlation was found between reading comprehension of texts and receptive vocabulary in the group without indicatives. In the absence of indicatives of reading and writing disorders, the presence of a good range of vocabulary highly contributes to a proficient reading comprehension of texts.

  20. Sibship size, sibling cognitive sensitivity, and children's receptive vocabulary.

    Science.gov (United States)

    Prime, Heather; Pauker, Sharon; Plamondon, André; Perlman, Michal; Jenkins, Jennifer

    2014-02-01

    The aim of the current study was to examine the relationship between sibship size and children's vocabulary as a function of quality of sibling interactions. It was hypothesized that coming from a larger sibship (ie, 3+ children) would be related to lower receptive vocabulary in children. However, we expected this association to be moderated by the level of cognitive sensitivity shown by children's next-in-age older siblings. Data on 385 children (mean age = 3.15 years) and their next-in-age older siblings (mean age = 5.57 years) were collected and included demographic questionnaires, direct testing of children's receptive vocabulary, and videos of mother-child and sibling interactions. Sibling dyads were taped engaging in a cooperative building task and tapes were coded for the amount of cognitive sensitivity the older sibling exhibited toward the younger sibling. Hierarchical regression analyses were conducted and showed an interaction between sibship size and sibling cognitive sensitivity in the prediction of children's receptive vocabulary; children exposed to large sibships whose next-in-age older sibling exhibited higher levels of cognitive sensitivity were less likely to show low vocabulary skills when compared with those children exposed to large sibships whose siblings showed lower levels of cognitive sensitivity. Children who show sensitivity to the cognitive needs of their younger siblings provide a rich environment for language development. The negative impact of large sibships on language development is moderated by the presence of an older sibling who shows high cognitive sensitivity.

  1. Clinical investigations of receptive and expressive musical functions after stroke

    Directory of Open Access Journals (Sweden)

    Ken eRosslau

    2015-06-01

    Full Text Available There is a long tradition of investigating various disorders of musical abilities after stroke. These impairments, associated with acquired amusia, can be highly selective, affecting only music perception (i.e., receptive abilities/functions or expression (music production abilities, and some patients report that these may dramatically influence their emotional state. The aim of this study was to systematically test both the melodic and rhythmic domains of music perception and expression in left- and right-sided stroke patients compared to healthy subjects. Music perception was assessed using rhythmic and melodic discrimination tasks, while tests of expressive function involved the vocal or instrumental reproduction of rhythms and melodies. Our approach revealed deficits in receptive and expressive functions in stroke patients, mediated by musical expertise. Those patients who had experienced a short period of musical training in childhood and adolescence performed better in the receptive and expressive subtests compared to those without any previous musical training. While discrimination of specific musical patterns was unimpaired after a right-sided stroke, patients with a left-sided stroke had worse results for fine melodic and rhythmic analysis. In terms of expressive testing, the most consistent results were obtained from a test that required patients to reproduce sung melodies. This implies that the means of investigating production abilities can impact the identification of deficits.

  2. Timing of pollen release and stigma receptivity period of Piper vicosanum: New insights into sexual reproduction of the genus.

    Science.gov (United States)

    Valentin-Silva, Adriano; Coelho, Victor Peçanha de Miranda; Ventrella, Marília Contin; Vieira, Milene Faria

    2015-04-01

    Dichogamy is a common characteristic among angiosperms, including Piper species. In this genus, the tiny flowers are morphologically similar and have an asynchronous stamen development. However, there is no information on the duration of stigma receptivity and whether it overlaps with pollen release. To better understand mechanisms of floral function in Piper vicosanum, we provide a detailed characterization of the timing of pollen release from the four stamens and the period of stigma receptivity and exposure mode of the receptive areas. We investigated plants of a natural population in a semideciduous seasonal forest (Viçosa, Minas Gerais State, southeastern Brazil), based on chemical tests, light microscopy, and scanning electron microscopy analyses. Incomplete protogyny-a mechanism that favors outcrossing-was recorded. The period of stigma receptivity was long (14 d), and the sequential exposure and senescence of stigmatic papillae occurred gradually and in a basipetal direction. Pollen release began 2-6 d after the beginning of the pistillate phase, with an average pollen viability of 87.7%, during the bisexual flower phase. Pollen was released for up to 6 d and occurred in one stamen at a time. The fruit set observed in tests of self-pollination indicated self-compatibility. The gradual and sequential exposure of stigmatic papillae in P. vicosanum flowers is described here as the mechanism for the long duration of receptivity. Anther development and pollen release were also sequential. These findings are yet unreported reproductive characteristics of the genus and offer new perspectives for future studies on the floral biology of other Piper species. © 2015 Botanical Society of America, Inc.

  3. Efficient full-spectrum utilization, reception and conversion of solar energy by broad-band nanospiral antenna.

    Science.gov (United States)

    Zhao, Huaqiao; Gao, Huotao; Cao, Ting; Li, Boya

    2018-01-22

    In this work, the collection of solar energy by a broad-band nanospiral antenna is investigated in order to solve the low efficiency of the solar rectenna based on conventional nanoantennas. The antenna impedance, radiation, polarization and effective area are all considered in the efficiency calculation using the finite integral technique. The wavelength range investigated is 300-3000 nm, which corresponds to more than 98% of the solar radiation energy. It's found that the nanospiral has stronger field enhancement in the gap than a nanodipole counterpart. And a maximum harvesting efficiency about 80% is possible in principle for the nanospiral coupled to a rectifier resistance of 200 Ω, while about 10% for the nanodipole under the same conditions. Moreover, the nanospiral could be coupled to a rectifier diode of high resistance more easily than the nanodipole. These results indicate that the efficient full-spectrum utilization, reception and conversion of solar energy can be achieved by the nanospiral antenna, which is expected to promote the solar rectenna to be a promising technology in the clean, renewable energy application.

  4. Method of optical coherence tomography with parallel depth-resolved signal reception and fibre-optic phase modulators

    Energy Technology Data Exchange (ETDEWEB)

    Morozov, A N; Turchin, I V [Institute of Applied Physics, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

    2013-12-31

    The method of optical coherence tomography with the scheme of parallel reception of the interference signal (P-OCT) is developed on the basis of spatial paralleling of the reference wave by means of a phase diffraction grating producing the appropriate time delay in the Mach–Zehnder interferometer. The absence of mechanical variation of the optical path difference in the interferometer essentially reduces the time required for 2D imaging of the object internal structure, as compared to the classical OCT that uses the time-domain method of the image construction, the sensitivity and the dynamic range being comparable in both approaches. For the resulting field of the interfering object and reference waves an analytical expression is derived that allows the calculation of the autocorrelation function in the plane of photodetectors. For the first time a method of linear phase modulation by 2π is proposed for P-OCT systems, which allows the use of compact high-frequency (a few hundred kHz) piezoelectric cell-based modulators. For the demonstration of the P-OCT method an experimental setup was created, using which the images of the inner structure of biological objects at the depth up to 1 mm with the axial spatial resolution of 12 μm were obtained. (optical coherence tomography)

  5. Gender Differences in Receptivity to Sexual Offers: A New Research Prototype

    Directory of Open Access Journals (Sweden)

    Mercedes Tappé

    2013-12-01

    Full Text Available Among the most cited series of experiments in social and evolutionary psychology are those conducted by Clark and Hatfield (1989, 2003. In these studies, college students served as confederates in a simple field experiment. They approached fellow college students of another gender and asked one of three questions: (a “Would you go out with me tonight?” (b “Would you come over to my apartment tonight?” or (c “Would you go to bed with me tonight?” Men and women differed markedly in their receptivity to casual sexual offers. When asked: “Would you go out with me tonight?” both were equally receptive. Yet, when confederates asked, “Would you come over to my apartment” or “Would you go to bed with me?” gender differences were striking. In the following series of experiments we attempted to develop a pencil and paper method to mirror the procedure of the classic study. We think we succeeded. Although cultural and social considerations may have influenced participants’ tendency to accept or reject sexual offers, as predicted by evolutionary perspectives, in all three experiments men were more likely than women to accept sexual offers. The studies also explored some of the reasons men and women gave for refusing a date, apartment visit, or a sexual encounter. We close by itemizing some questions that, given this new set of research materials, may be worth asking.

  6. Receptivity and Forced Response to Acoustic Disturbances in High-Speed Boundary Layers

    Science.gov (United States)

    Balakumar, P.; King, Rudolph A.; Chou, Amanda; Owens, Lewis R.; Kegerise, Michael A.

    2016-01-01

    Supersonic boundary-layer receptivity to freestream acoustic disturbances is investigated by solving the Navier-Stokes equations for Mach 3.5 flow over a sharp flat plate and a 7-deg half-angle cone. The freestream disturbances are generated from a wavy wall placed at the nozzle wall. The freestream acoustic disturbances radiated by the wavy wall are obtained by solving the linearized Euler equations. The results for the flat plate show that instability modes are generated at all the incident angles ranging from zero to highly oblique. However, the receptivity coefficient decreases by about 20 times when the incident angle increases from zero to a highly oblique angle of 68 degrees. The results for the cone show that no instability modes are generated when the acoustic disturbances impinge the cone obliquely. The results show that the perturbations generated inside the boundary layer by the acoustic disturbances are the response of the boundary layer to the external forcing. The amplitude of the forced disturbances inside the boundary layer are about 2.5 times larger than the incoming field for zero azimuthal wavenumber and they are about 1.5 times for large azimuthal wavenumbers.

  7. U.S.-Portuguese Relations and Lajes Field Air Base

    Science.gov (United States)

    2014-12-01

    by Manuel Martins entitled Base Aerea das Lajes (contribuicao para a sua historia ) Lajes Air Base11 specifically deals with the historical events...11 Manuel Martins, Base Aerea das Lajes (Contribuição Para a Sua Historia ) [Lajes Air Base (Contribution to its History)] (Azores

  8. Optoelectrofluidic field separation based on light-intensity gradients.

    Science.gov (United States)

    Lee, Sanghyun; Park, Hyun Jin; Yoon, Jin Sung; Kang, Kwan Hyoung

    2010-07-14

    Optoelectrofluidic field separation (OEFS) of particles under light -intensity gradient (LIG) is reported, where the LIG illumination on the photoconductive layer converts the short-ranged dielectrophoresis (DEP) force to the long-ranged one. The long-ranged DEP force can compete with the hydrodynamic force by alternating current electro-osmosis (ACEO) over the entire illumination area for realizing effective field separation of particles. In the OEFS system, the codirectional illumination and observation induce the levitation effect, compensating the attenuation of the DEP force under LIG illumination by slightly floating particles from the surface. Results of the field separation and concentration of diverse particle pairs (0.82-16 mum) are well demonstrated, and conditions determining the critical radius and effective particle manipulation are discussed. The OEFS with codirectional LIG strategy could be a promising particle manipulation method in many applications where a rapid manipulation of biological cells and particles over the entire working area are of interest.

  9. Asynchronous Distributed Execution of Fixpoint-Based Computational Fields

    DEFF Research Database (Denmark)

    Lluch Lafuente, Alberto; Loreti, Michele; Montanari, Ugo

    2017-01-01

    . Computational fields are a key ingredient of aggregate programming, a promising software engineering methodology particularly relevant for the Internet of Things. In our approach, space topology is represented by a fixed graph-shaped field, namely a network with attributes on both nodes and arcs, where arcs...... represent interaction capabilities between nodes. We propose a SMuC calculus where µ-calculuslike modal formulas represent how the values stored in neighbor nodes should be combined to update the present node. Fixpoint operations can be understood globally as recursive definitions, or locally...

  10. Transformations Based on Continuous Piecewise-Affine Velocity Fields

    DEFF Research Database (Denmark)

    Freifeld, Oren; Hauberg, Søren; Batmanghelich, Kayhan

    2017-01-01

    We propose novel finite-dimensional spaces of well-behaved transformations. The latter are obtained by (fast and highly-accurate) integration of continuous piecewise-affine velocity fields. The proposed method is simple yet highly expressive, effortlessly handles optional constraints (e.g., volume...

  11. Optical Doppler tomography based on a field programmable gate array

    DEFF Research Database (Denmark)

    Larsen, Henning Engelbrecht; Nilsson, Ronnie Thorup; Thrane, Lars

    2008-01-01

    We report the design of and results obtained by using a field programmable gate array (FPGA) to digitally process optical Doppler tomography signals. The processor fits into the analog signal path in an existing optical coherence tomography setup. We demonstrate both Doppler frequency and envelope...

  12. The development of simple field based procedures for extraction of ...

    African Journals Online (AJOL)

    Field and laboratory experiments were conducted to develop procedures for extracting volatiles from the vine of Adenia cissampeloides which could effect the highest yield at the lowest extraction costs and also could be produced at the cottage industry level. The participatory rural appraisal technique was used to ensure ...

  13. Place-Based Care Ethics: A Field Philosophy Pedagogy

    Science.gov (United States)

    Goralnik, Lissy; Dobson, Tracy; Nelson, Michael Paul

    2014-01-01

    In this paper we argue for the need for a thoughtful and intentional pedagogy in experiential environmental learning that educates for empathetic relationships with humans, nonhuman others, and natural systems, or field philosophy. After discussing the tensions in various ecofeminist perspectives, we highlight relevant ecofeminist ideas and thread…

  14. Agent-based modelling of shifting cultivation field patterns, Vietnam

    DEFF Research Database (Denmark)

    Jepsen, Martin Rudbeck; Leisz, S.; Rasmussen, K.

    2006-01-01

    costs associated with fencing of fields, and are faced with physical constraints. The simulation results are compared with land-cover data obtained from remote sensing. Comparisons are made on patterns as detected visually and using the mean nearest-neighbour ratio. Baseline simulation outputs show high...

  15. Development of a Layered Conditional Random Field Based ...

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    2014-12-01

    Dec 1, 2014 ... Conditional Estimation in NLP Models,” Proc. ACL Conf. Empirical. Methods in Natural Language Processing (EMNLP '02), Association for. Computational Linguistics, 10, (9-16). [39] Sutton, C. and McCallum, A (2006). “An Introduction to Conditional Random Fields for. Relational Learning,” Introduction to ...

  16. Training Outcomes of Field Instructors in the Evidence-Based Practice Process Model

    Science.gov (United States)

    Matthieu, Monica M.; Carter, Lorien; Casner, Robert W.; Edmond, Tonya E.

    2016-01-01

    This study evaluated a continuing education training program designed to increase field educators' capacities to support students in their application of the evidence-based practice (EBP) process. A cohort of social work field instructors and task supervisors from agency-based settings (N = 186) attended a 1-day interactive skill-based training.…

  17. Structural mapping based on potential field and remote sensing data ...

    Indian Academy of Sciences (India)

    Swarnapriya Chowdari

    2017-08-31

    Aug 31, 2017 ... suitable filter function. g (f) = [. 2Gρ exp. (. −. 2fz0 λ. )] z (f) where g(f) is the transforms of the observed gravity fields, f is the spatial frequency, z(f) is the fourier transform of the basement relief over the average depth zo, ρ is the density contrast across the basement relief and λ is the wavelength equal ...

  18. A Field-Based Aquatic Life Benchmark for Conductivity in ...

    Science.gov (United States)

    This report adapts the standard U.S. EPA methodology for deriving ambient water quality criteria. Rather than use toxicity test results, the adaptation uses field data to determine the loss of 5% of genera from streams. The method is applied to derive effect benchmarks for dissolved salts as measured by conductivity in Central Appalachian streams using data from West Virginia and Kentucky. This report provides scientific evidence for a conductivity benchmark in a specific region rather than for the entire United States.

  19. Modelling coronal electron density and temperature profiles based on solar magnetic field observations

    Science.gov (United States)

    Rodríguez Gómez, J. M.; Antunes Vieira, L. E.; Dal Lago, A.; Palacios, J.; Balmaceda, L. A.; Stekel, T.

    2017-10-01

    The density and temperature profiles in the solar corona are complex to describe, the observational diagnostics is not easy. Here we present a physics-based model to reconstruct the evolution of the electron density and temperature in the solar corona based on the configuration of the magnetic field imprinted on the solar surface. The structure of the coronal magnetic field is estimated from Potential Field Source Surface (PFSS) based on magnetic field from both observational synoptic charts and a magnetic flux transport model. We use an emission model based on the ionization equilibrium and coronal abundances from CHIANTI atomic database 8.0. The preliminary results are discussed in details.

  20. Real-time temperature field measurement based on acoustic tomography

    Science.gov (United States)

    Bao, Yong; Jia, Jiabin; Polydorides, Nick

    2017-07-01

    Acoustic tomography can be used to measure the temperature field from the time-of-flight (TOF). In order to capture real-time temperature field changes and accurately yield quantitative temperature images, two improvements to the conventional acoustic tomography system are studied: simultaneous acoustic transmission and TOF collection along multiple ray paths, and an offline iteration reconstruction algorithm. During system operation, all the acoustic transceivers send modulated and filtered wideband Kasami sequences simultaneously to facilitate fast and accurate TOF measurements using cross-correlation detection. For image reconstruction, the iteration process is separated and executed offline beforehand to shorten computation time for online temperature field reconstruction. The feasibility and effectiveness of the developed methods are validated in the simulation study. The simulation results demonstrate that the proposed method can reduce the processing time per frame from 160 ms to 20 ms, while the reconstruction error remains less than 5%. Hence, the proposed method has great potential in the measurement of rapid temperature change with good temporal and spatial resolution.

  1. Routing optimization in networks based on traffic gravitational field model

    Science.gov (United States)

    Liu, Longgeng; Luo, Guangchun

    2017-04-01

    For research on the gravitational field routing mechanism on complex networks, we further analyze the gravitational effect of paths. In this study, we introduce the concept of path confidence degree to evaluate the unblocked reliability of paths that it takes the traffic state of all nodes on the path into account from the overall. On the basis of this, we propose an improved gravitational field routing protocol considering all the nodes’ gravities on the path and the path confidence degree. In order to evaluate the transmission performance of the routing strategy, an order parameter is introduced to measure the network throughput by the critical value of phase transition from a free-flow phase to a jammed phase, and the betweenness centrality is used to evaluate the transmission performance and traffic congestion of the network. Simulation results show that compared with the shortest-path routing strategy and the previous gravitational field routing strategy, the proposed algorithm improves the network throughput considerably and effectively balances the traffic load within the network, and all nodes in the network are utilized high efficiently. As long as γ ≥ α, the transmission performance can reach the maximum and remains unchanged for different α and γ, which ensures that the proposed routing protocol is high efficient and stable.

  2. Alternative current source based Schottky contact with additional electric field

    Science.gov (United States)

    Mamedov, R. K.; Aslanova, A. R.

    2017-07-01

    Additional electric field (AEF) in the Schottky contacts (SC) that covered the peripheral contact region wide and the complete contact region narrow (as TMBS diode) SC. Under the influence of AEF is a redistribution of free electrons produced at certain temperatures of the semiconductor, and is formed the space charge region (SCR). As a result of the superposition of the electric fields SCR and AEF occurs the resulting electric field (REF). The REF is distributed along a straight line perpendicular to the contact surface, so that its intensity (and potential) has a minimum value on the metal surface and the maximum value at a great distance from the metal surface deep into the SCR. Under the influence of AEF as a sided force the metal becomes negative pole and semiconductor - positive pole, therefore, SC with AEF becomes an alternative current source (ACS). The Ni-nSi SC with different diameters (20-1000 μm) under the influence of the AEF as sided force have become ACS with electromotive force in the order of 0.1-1.0 mV, which are generated the electric current in the range of 10-9-10-7 A, flowing through the external resistance 1000 Ohm.

  3. Near field ice detection using infrared based optical imaging technology

    Science.gov (United States)

    Abdel-Moati, Hazem; Morris, Jonathan; Zeng, Yousheng; Corie, Martin Wesley; Yanni, Victor Garas

    2018-02-01

    If not detected and characterized, icebergs can potentially pose a hazard to oil and gas exploration, development and production operations in arctic environments as well as commercial shipping channels. In general, very large bergs are tracked and predicted using models or satellite imagery. Small and medium bergs are detectable using conventional marine radar. As icebergs decay they shed bergy bits and growlers, which are much smaller and more difficult to detect. Their low profile above the water surface, in addition to occasional relatively high seas, makes them invisible to conventional marine radar. Visual inspection is the most common method used to detect bergy bits and growlers, but the effectiveness of visual inspections is reduced by operator fatigue and low light conditions. The potential hazard from bergy bits and growlers is further increased by short detection range (<1 km). As such, there is a need for robust and autonomous near-field detection of such smaller icebergs. This paper presents a review of iceberg detection technology and explores applications for infrared imagers in the field. Preliminary experiments are performed and recommendations are made for future work, including a proposed imager design which would be suited for near field ice detection.

  4. Field efficacy of inorganic carrier based formulations of Serratia ...

    African Journals Online (AJOL)

    In the present study, an attempt was taken to reduce the use of chemical pesticide and fertilizer by using two inorganic carriers (talcum powder and vermiculite) based formulation of S. entomophila in sesame. From the experimental results it was evident that the vermiculite based formulation of S. entomophila AB2 proved a ...

  5. Longitudinal analysis of receptive vocabulary growth in young Spanish English-speaking children from migrant families.

    Science.gov (United States)

    Jackson, Carla Wood; Schatschneider, Christopher; Leacox, Lindsey

    2014-01-01

    The authors of this study described developmental trajectories and predicted kindergarten performance of Spanish and English receptive vocabulary acquisition of young Latino/a English language learners (ELLs) from socioeconomically disadvantaged migrant families. In addition, the authors examined the extent to which gender and individual initial performance in Spanish predict receptive vocabulary performance and growth rate. The authors used hierarchical linear modeling of 64 children's receptive vocabulary performance to generate growth trajectories, predict performance at school entry, and examine potential predictors of rate of growth. The timing of testing varied across children. The ELLs (prekindergarten to 2nd grade) participated in 2-5 testing sessions, each 6-12 months apart. The ELLs' average predicted standard score on an English receptive vocabulary at kindergarten was nearly 2 SDs below the mean for monolingual peers. Significant growth in the ELLs' receptive vocabulary was observed between preschool and 2nd grade, indicating that the ELLs were slowly closing the receptive vocabulary gap, although their average score remained below the standard score mean for age-matched monolingual peers. The ELLs demonstrated a significant decrease in Spanish receptive vocabulary standard scores over time. Initial Spanish receptive vocabulary was a significant predictor of growth in English receptive vocabulary. High initial Spanish receptive vocabulary was associated with greater growth in English receptive vocabulary and decelerated growth in Spanish receptive vocabulary. Gender was not a significant predictor of growth in either English or Spanish receptive vocabulary. ELLs from low socioeconomic backgrounds may be expected to perform lower in English compared with their monolingual English peers in kindergarten. Performance in Spanish at school entry may be useful in identifying children who require more intensive instructional support for English vocabulary

  6. DMD-based programmable wide field spectrograph for Earth observation

    Science.gov (United States)

    Zamkotsian, Frédéric; Lanzoni, Patrick; Liotard, Arnaud; Viard, Thierry; Costes, Vincent; Hébert, Philippe-Jean

    2015-03-01

    In Earth Observation, Universe Observation and Planet Exploration, scientific return could be optimized in future missions using MOEMS devices. In Earth Observation, we propose an innovative reconfigurable instrument, a programmable wide-field spectrograph where both the FOV and the spectrum could be tailored thanks to a 2D micromirror array (MMA). For a linear 1D field of view (FOV), the principle is to use a MMA to select the wavelengths by acting on intensity. This component is placed in the focal plane of a first grating. On the MMA surface, the spatial dimension is along one side of the device and for each spatial point, its spectrum is displayed along the perpendicular direction: each spatial and spectral feature of the 1D FOV is then fully adjustable dynamically and/or programmable. A second stage with an identical grating recomposes the beam after wavelengths selection, leading to an output tailored 1D image. A mock-up has been designed, fabricated and tested. The micromirror array is the largest DMD in 2048 x 1080 mirrors format, with a pitch of 13.68μm. A synthetic linear FOV is generated and typical images have been recorded o at the output focal plane of the instrument. By tailoring the DMD, we could modify successfully each pixel of the input image: for example, it is possible to remove bright objects or, for each spatial pixel, modify the spectral signature. The very promising results obtained on the mock-up of the programmable wide-field spectrograph reveal the efficiency of this new instrument concept for Earth Observation.

  7. Methodological bases of innovative training of specialists in nanotechnology field

    Directory of Open Access Journals (Sweden)

    FIGOVSKY Oleg Lvovich

    2016-10-01

    Full Text Available The performance of innovative training system aimed at highly intellectual specialists in the area of nanotechnologies for Kazakhstan’s economy demands establishment and development of nanotechnological market in the country, teaching of innovative engineering combined with consistent research, integration of trained specialists with latest technologies and sciences at the international level. Methodological aspects of training competitive specialists for nanotechnological field are specific. The paper presents methodological principles of innovative training of specialists for science-intensive industry that were realized according to grant given by the Ministry of Education and Science of the Republic of Kazakhstan.

  8. Magneto Inertial Fusion Based on a Cusp Field Configuration

    CERN Document Server

    Ryzhkov, S V

    2009-01-01

    We study the cusp configuration of pre-seeded magnetic field for laser-driven flux-compression. The proposed configuration provides better particle confinement than that in Ref. [O.V. Gotchev et al., Journal of Fusion Energy 27 (2008) 25-31.] thereby leading to better magnetic insulation of hot fusion plasma. We develop the model that takes into account (i) magnetized target implosion, (ii) magnetic flux compression; (iii) particle losses from magnetic trap. The key parameter governing the process is the ratio of the implosion time to the particle loss time.

  9. Immune ontogeny and engraftment receptivity in the sheep fetus.

    Science.gov (United States)

    Skopal-Chase, Jessica L; Pixley, John S; Torabi, Alireza; Cenariu, Mihai C; Bhat, Anupama; Thain, David S; Frederick, Nicole M; Groza, Daria M; Zanjani, Esmail D

    2009-01-01

    The biologic explanation for fetal receptivity to donor engraftment and subsequent long-term tolerance following transplantation early in gestation is not known. We investigated the role fetal immune ontogeny might play in fetal transplantation tolerance in sheep. Engraftment of allogeneic and xenogeneic HSC was determined 60 days following transplantation at different time points in sheep fetal gestation. Parallel analysis of surface differentiation antigen expression on cells from lymphoid organs of timed gestational age fetal sheep was determined by flow cytometry using available reagents. An engraftment window was identified after day 52 gestation lasting until day 71 (term gestation: 145 days). This period was associated with the expression of the leukocyte common antigen CD45 on all cells in the thymus. Double-positive and single-positive CD4 and CD8 cells began appearing in the thymus just prior (day 45 gestation) to the beginning of the engraftment window, while single-positive CD4 or CD8 cells do not begin appearing in peripheral organs until late in the engraftment period, suggesting deletional mechanisms may be operative. In concert, surface IgM-positive cells express CD45 in the thymus at day 45, with a comparable delay in the appearance of IgM/CD45 cells in the periphery until late in the engraftment window. These findings support a central role for the thymus in multilineage immune cell maturation during the period of fetal transplantation receptivity. Further, they suggest that fetal engraftment receptivity is due to gestational age-dependent deletional tolerance. (c) 2009 S. Karger AG, Basel.

  10. Membrane–initiated estradiol signaling regulating sexual receptivity

    Directory of Open Access Journals (Sweden)

    Paul E Micevych

    2011-09-01

    Full Text Available Estradiol has profound actions on the structure and function of the nervous system. In addition to nuclear actions that directly modulate gene expression, the idea that estradiol can rapidly activate cell signaling by binding to membrane estrogen receptors (mERs has emerged. Even the regulation of sexual receptivity, an action previously thought to be completely regulated by nuclear ERs, has been shown to have a membrane-initiated estradiol signaling (MIES component. This highlighted the question of the nature of mERs. Several candidates have been proposed, ERα, ERβ, ER-X, GPR30 (G protein coupled estrogen receptor; GPER, and a receptor activated by a diphenylacrylamide compound, STX. Although each of these receptors has been shown to be active in specific assays, we present evidence for and against their participation in sexual receptivity by acting in the lordosis-regulating circuit. The initial MIES that activates the circuit is in the arcuate nucleus of the hypothalamus (ARH. Using both activation of μ-opioid receptors (MOR in the medial preoptic nucleus and lordosis behavior, we document that both ERα and the STX receptor participate in the required MIES. ERα and the STX receptor activation of cell signaling are dependent on the transactivation of type 1 metabotropic glutamate receptors (mGluR1a that augment progesterone synthesis in astrocytes and protein kinase C (PKC in ARH neurons. While estradiol-induced sexual receptivity does not depend on neuroprogesterone, proceptive behaviors do. Moreover, the ERα and the STX receptor activation of medial preoptic MORs and augmentation of lordosis were sensitive to mGluR1a blockade. These observations suggest a common mechanism through which mERs are coupled to intracellular signaling cascades, not just in regulating reproduction, but in actions throughout the neuraxis including the cortex, hippocampus, striatum and DRGs.

  11. Low Emittance Gun Project based on Field Emission

    CERN Document Server

    Ganter, Romain; Dehler, M; Gobrecht, Jens; Gough, Chris; Ingold, Gerhard; Leemann, Simon C; Shing-Bruce-Li, Kevin; Paraliev, Martin; Pedrozzi, Marco; Raguin, Jean Yves; Rivkin, Leonid; Schlott, Volker; Sehr, Harald; Streun, Andreas; Wrulich, Albin F; Zelenika, Sasa

    2004-01-01

    The design of an electron gun capable of producing beam emittance one order of magnitude lower than current technology would reduce considerably the cost and size of a free electron laser emitting at 0.1nm. Field emitter arrays (FEAs) including a gate and a focusing layer are an attractive technology for such high brightness sources. Electrons are extracted from micrometric tips thanks to voltage pulses between gate and tips. The focusing layer should then reduce the initial divergence of each emitted beamlets. This FEA will be inserted in a high gradient diode configuration coupled with a radiofrequency structure. In the diode part very high electric field pulses (several hundreds of MV/m) will limit the degradation of emittance due to space charge effect. This first acceleration will be obtained with high voltage pulses (typically a megavolt in a few hundred of nanoseconds) synchronized with the low voltage pulses applied to the FEA (typically one hundred of volts in one nanosecond at frequency below kilohe...

  12. Context-Based Assessment: Creating Opportunities for Resonance between Classroom Fields and Societal Fields

    Science.gov (United States)

    Bellocchi, Alberto; King, Donna T.; Ritchie, Stephen M.

    2016-01-01

    There is on-going international interest in the relationships between assessment instruments, students' understanding of science concepts and context-based curriculum approaches. This study extends earlier research showing that students can develop connections between contexts and concepts--called "fluid transitions"--when studying…

  13. Aesthetics of reception, Jauss, implied reader and actual reader.

    OpenAIRE

    Jefferson Cleiton de Souza

    2012-01-01

    The aim of this paper is to discuss how Hans Robert Jauss, the creator of the aesthetics of reception, has introduced the category of the reader into the literary studies especially when it comes to the importance of the reader to the understanding of the text, and to the history of a society and its literary system or, in other words to the way the formal elements of a literary work are organized and how they are related to aesthetic, ethic and moral evaluations. To do so, it is necessary to...

  14. Life Is Strange a mediated game reception analysis

    OpenAIRE

    Mänder, Leili

    2017-01-01

    In this essay a mediated video game reception of the game Life Is Strange is made, with the purpose of examining the players' meaning-making processes from a gender perspective. The materials of this essay consist of videos from six different YouTube channels where each player film themselves whilst playing through Life Is Strange as a way to review and share the gaming experience. The results show how the meaning-making processes are littered with gender discourses and affects. The affects o...

  15. Measurements of Electromagnetic Fields Emitted from Cellular Base Stations in

    National Research Council Canada - National Science Library

    K. J. Ali

    2013-01-01

    .... The aim of this work is to determine the safe and unsafe ranges and discuss damage caused by radiation emitted from Asia cell base stations in Shirqat city and discuses the best ways in which can...

  16. Field-based Metabolomics for Assessing Contaminated Surface Waters

    Science.gov (United States)

    Metabolomics is becoming well-established for studying chemical contaminant-induced alterations to normal biological function. For example, the literature contains a wealth of laboratory-based studies involving analysis of samples from organisms exposed to individual chemical tox...

  17. Building Macro-models for Waveform Inversion using Strip-off Controlled Directional Reception Velocity Analysis

    Science.gov (United States)

    Park, Eunjin; Shin, Changsoo

    2017-04-01

    The controlled directional reception (CDR) method is a velocity analysis method using ray-tracing. It is one of the tomographic methods that use slope (or ray parameter), so it is often called the "slope tomography method". It does not require a pre-picking operation like traveltime tomography does. Auto-picked information from the local slant stack is regarded as more reliable than reflection traveltime picked directly from the seismic data. The method also provides more detailed information about the moveout than the imaging operator in migration-based velocity analysis (MVA). Therefore, we constructed a velocity macro-model using this strip-off CDR velocity analysis. When compared to the conventional CDR method, it increased the resolution of common receiver gathers (CRG) data and reduced computer storage space dramatically. Additionally, it improved the accuracy of the velocity model by using the migrated image as a background panel during the velocity analysis. The results obtained by this method were applied to full waveform inversion (FWI) as the initial velocity model. In FWI, an exact initial model is important because it reduces instability and increases the probability of convergence to the global minimum. It is significant that the CDR model is first applied as the initial model of FWI. We confirmed good inverted results from two realistic synthetic data tests by comparison with the results obtained using the conventional initial models. In particular, the CDR macro-model has great value on its high accuracy. It is expected to provide good results with difficult data, such as seismic data with a weathered zone or short offset, and so increase the accuracy compared with the conventional method. Furthermore, it is possible to apply to multi-parameter inversion. In summary, the macro-model obtained from strip-off CDR velocity analysis is suitable for frequency domain FWI. Three-dimensional exploration and exploration in complex terrains are being conducted

  18. Safety impact of an integrated crash warning system based on field test data.

    Science.gov (United States)

    2011-06-13

    This paper provides the results of an analysis : conducted to assess the safety impact of an integrated : vehicle-based crash warning system based on : naturalistic driving data collected from a field : operational test. The system incorporates four ...

  19. To Investigate the Absorption, Dynamic Contact Angle and Printability Effects of Synthetic Zeolite Pigments in an Inkjet Receptive Coating

    Science.gov (United States)

    Jalindre, Swaraj Sunil

    Ink absorption performance in inkjet receptive coatings containing synthetic zeolite pigments was studied. Coating pigment pore and particle size distribution are the key parameters that influence in modifying media surface properties, thus affecting the rate of ink penetration and drying time (Scholkopf, et al. 2004). The primary objective of this study was: (1) to investigate the synthetic zeolite pigment effects on inkjet ink absorption, dynamic contact angle and printability, and (2) to evaluate these novel synthetic zeolite pigments in replacing the fumed silica pigments in conventional inkjet receptive coatings. In this research study, single pigment coating formulations (in equal P:B ratio) were prepared using microporous synthetic zeolite pigments (5A, Organophilic and 13X) and polyvinyl alcohol (PVOH) binder. The laboratory-coated samples were characterized for absorption, air permeance, roughness, drying time, wettability and print fidelity. Based on the rheological data, it was found that the synthetic zeolite formulated coatings depicted a Newtonian flow behavior at low shear; while the industry accepted fumed silica based coatings displayed a characteristically high pseudoplastic flow behavior. Our coated samples generated using microporous synthetic zeolite pigments produced low absorption, reduced wettability and accelerated ink drying characteristics. These characteristics were caused due to the synthetic zeolite pigments, which resulted in relatively closed surface structure coated samples. The research suggested that no single selected synthetic zeolite coating performed better than the conventional fumed silica based coatings. Experimental data also showed that there was no apparent relationship between synthetic zeolite pigment pore sizes and inkjet ink absorption. For future research, above coated samples should be evaluated for pore size distribution using Mercury Porosimeter, which quantifies surface porosity of coated samples. This presented

  20. A modified incidental-teaching procedure for autistic youth: acquisition and generalization of receptive object labels.

    Science.gov (United States)

    McGee, G G; Krantz, P J; Mason, D; McClannahan, L E

    1983-01-01

    A modified incidental-teaching procedure was used to increase the receptive language skills of autistic youth who had previously experienced lengthy institutionalization. At the time of the study, the two severely language-delayed children had recently been transitioned to a community-based group home. Receptive-labeling skills were taught for four sets of objects typically used in school lunch preparation. The percentage of correct, unprompted object identifications displayed by Youth 1 increased when the incidental-teaching package (gestural prompts, behavior-specific praise, and contingent access to lunch-making supplies) was sequentially introduced in a multiple-baseline design across sets of objects. These results were replicated with Youth 2. The youths' newly acquired language skills also generalized to a different setting (the dining room of the group home) and to a different activity occurring later in the day (a traditional sit-down, discrete-trial session). This research indicates that the linguistic skills of severely developmentally delayed autistic children can be accelerated by incidental instruction that is provided in the course of shaping other home-living skills.

  1. Acoustic pathways revealed: simulated sound transmission and reception in Cuvier's beaked whale (Ziphius cavirostris).

    Science.gov (United States)

    Cranford, Ted W; Krysl, Petr; Hildebrand, John A

    2008-03-01

    The finite element modeling (FEM) space reported here contains the head of a simulated whale based on CT data sets as well as physical measurements of sound-propagation characteristics of actual tissue samples. Simulated sound sources placed inside and outside of an adult male Cuvier's beaked whale (Ziphius cavirostris) reveal likely sound propagation pathways into and out of the head. Two separate virtual sound sources that were located at the left and right phonic lips produced beams that converged just outside the head. This result supports the notion that dual sound sources can interfere constructively to form a biologically useful and, in fact, excellent sonar beam in front of the animal. The most intriguing FEM results concern pathways by which sounds reach the ears. The simulations reveal a previously undescribed 'gular pathway' for sound reception in Ziphius. Propagated sound pressure waves enter the head from below and between the lower jaws, pass through an opening created by the absence of the medial bony wall of the posterior mandibles, and continue toward the bony ear complexes through the internal mandibular fat bodies. This new pathway has implications for understanding the evolution of underwater hearing in odontocetes. Our model also provides evidence for receive beam directionality, off-axis acoustic shadowing and a plausible mechanism for the long-standing orthodox sound reception pathway in odontocetes. The techniques developed for this study can be used to study acoustic perturbation in a wide variety of marine organisms.

  2. Development of a Mandarin Expressive and Receptive Vocabulary Test for children using cochlear implants.

    Science.gov (United States)

    Lu, Xiaopan; Wong, Lena L-N; Wong, Anita M-Y; Xi, Xin

    2013-10-01

    Cochlear implants (CIs) provide children with profound hearing loss access to sounds and speech. Research on the effects of CI on speech and language development in mainland China is scarce due to the lack of standardized tests. This study aims at developing a vocabulary measure, the Mandarin Expressive and Receptive Vocabulary Test (MERVT), for pre-school children with CIs. Using responses from 102 normal-hearing preschool children, the initial vocabulary set was subjected to analyses to identify items with appropriate levels of difficulty and discrimination. Norms on 245 normal-hearing children aged 1;6 to 3;11 were later collected based on the final set of the items. Evaluation of the test's psychometric properties revealed good internal consistency. Significant correlations between the total MERVT scores and the Gesell Developmental Scale scores, between the MERVT expressive and receptive subtest scores and the total scores, and the gradual increase in MERVT scores with age, provided evidence of construct validity. Results from 29 children with CIs were also examined for evidence of the MERVT's construct validity. There was a significant correlation between these children's MERVT scores and their scores from an intelligence test. The MERVT scores increased with an increase in the duration of CI use and in chronological age. With good reliability and strong validity, the test is recommended for use in the monitoring of language development in children with CI. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. AL-FEC for Improved Mobile Reception of MPEG-2 DVB-T Transport Streams

    Directory of Open Access Journals (Sweden)

    David Gozálvez

    2009-01-01

    Full Text Available We investigate the use of application layer FEC protection in DVB-T (Digital Video Broadcasting-Terrestrial networks for the provision of mobile services. Mobile reception is characterized by variations of the received signal caused by fast fading and shadowing. DVB-T was originally designed for fixed and portable reception, and generally does not provide enough quality in mobile environments. The link layer protection mechanism MPE-FEC (Multi Protocol Encapsulation-Forward Error Correction was standardized in DVB-H (Digital Video Broadcasting-Handheld for the protection of mobile TV services. Although DVB-T itself does not incorporate any link or application layer protection mechanism, AL-FEC (Application layer Forward Error Correction protection can be introduced in DVB-T in a backwards compatible way. By means of AL-FEC, it is possible to improve the robustness of DVB-T services for the provision of mobile TV. In this paper, we explain the concept of AL-FEC protection in DVB-T and evaluate its performance by means of laboratory measurements and dynamic simulations with shadowing. We study different configurations of AL-FEC and compare its performance with MPE-FEC. In this paper, we discuss some implementation aspects of AL-FEC in real scenarios and propose an implementation based on Raptor codes and hash sequences. We also present results obtained by a first AL-FEC prototype for DVB-T that demonstrates the feasibility of the approach.

  4. Underwater Acoustic Matched Field Imaging Based on Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Huichen Yan

    2015-10-01

    Full Text Available Matched field processing (MFP is an effective method for underwater target imaging and localizing, but its performance is not guaranteed due to the nonuniqueness and instability problems caused by the underdetermined essence of MFP. By exploiting the sparsity of the targets in an imaging area, this paper proposes a compressive sensing MFP (CS-MFP model from wave propagation theory by using randomly deployed sensors. In addition, the model’s recovery performance is investigated by exploring the lower bounds of the coherence parameter of the CS dictionary. Furthermore, this paper analyzes the robustness of CS-MFP with respect to the displacement of the sensors. Subsequently, a coherence-excluding coherence optimized orthogonal matching pursuit (CCOOMP algorithm is proposed to overcome the high coherent dictionary problem in special cases. Finally, some numerical experiments are provided to demonstrate the effectiveness of the proposed CS-MFP method.

  5. A LabVIEW based cyclotron magnetic field mapping system

    Energy Technology Data Exchange (ETDEWEB)

    Marti, F.; Johnson, P. [NSCL, Michigan State University, East Lansing, MI (United States)

    1999-07-01

    This paper describes the application of National Instruments LabVIEW to the NSCL K500 magnet mapping, as part of the Coupled Cyclotron Upgrade. LabVIEW provides a fast development environment for hardware control from a PC running Windows NT. The PC and LabVIEW environment allow non-professional computer programmers to obtain a reliable and flexible system where modifications can be quickly implemented. This program supports the use of motor controllers, data acquisition cards, digital I/O modules and GPIB instruments. A complete map of 360 degrees is obtained in approximately 90 minutes, measuring 185000 field values with a spacing of 1.6 mm in radius every degree. (author)

  6. Geothermal emissions data base: Cerro Prieto geothermal field

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, S.R. (comp.)

    1978-04-01

    A new database subset on the gaseous emissions from the Cerro Prieto geothermal field is presented. Properties and states of the reservoir fluid such as flow rates, wellhead pressure, and enthalpy are included in the file along with the well name and constituent measurement. This subset is the result of an initial screening of the data covering 1967 to 1969, and new additions will be appended periodically to the file. The data are accessed by a database management system as are all other subsets in the file. Thereby, one may search the database for specific data requirements and print selective output. For example, one may wish to locate reservoir conditions for cases only when the level of the constituent exceeded a designated value. Data output is available in the form of numerical compilations such as the attached, or graphical displays disposed to paper, film, or magnetic tape.

  7. Study on the temperature characteristics of LPFG magnetic field sensor based on magnetic fluid

    Science.gov (United States)

    Li, Yaocheng; Wang, Haitong; Xin, Zhao

    2015-02-01

    This paper carries out theoretical research and numerical simulation on the temperature characteristics of LPFG magnetic field sensor based on magnetic fluids. The simulation results show that the change of ambient temperature can make coupling resonance wavelength of the long period fiber grating drift, change the refractive index of magnetic fluids, which affects the measurement precision of the magnetic field. Our research has a certain significance for the practical application of LPFG magnetic field sensor based on magnetic fluids.

  8. The Impact of an Inquiry-Based Geoscience Field Course on Pre-Service Teachers

    Science.gov (United States)

    Nugent, Gwen; Toland, Michael D.; Levy, Richard; Kunz, Gina; Harwood, David; Green, Denise; Kitts, Kathy

    2012-01-01

    The purpose of this quasi-experimental study was to determine the effects of a field-based, inquiry-focused course on pre-service teachers' geoscience content knowledge, attitude toward science, confidence in teaching science, and inquiry understanding and skills. The field-based course was designed to provide students with opportunities to…

  9. Effectiveness of Mobile Apps in Teaching Field-Based Identification Skills

    Science.gov (United States)

    Thomas, Rebecca L.; Fellowes, Mark D. E.

    2017-01-01

    It has been suggested that few students graduate with the skills required for many ecological careers, as field-based learning is said to be in decline in academic institutions. Here, we asked if mobile technology could improve field-based learning, using ability to identify birds as the study metric. We divided a class of ninety-one undergraduate…

  10. Design of a Millimeter-Wave Concentrator for Beam Reception in High-Power Wireless Power Transfer

    Science.gov (United States)

    Fukunari, Masafumi; Wongsuryrat, Nat; Yamaguchi, Toshikazu; Nakamura, Yusuke; Komurasaki, Kimiya; Koizumi, Hiroyuki

    2017-02-01

    This study examined the performance of a developed taper-tube concentrator for 94-GHz millimeter-wave beam reception during wireless power transfer. The received energy is converted into kinetic energy of a working gas in the tube to drive an engine or thruster. The concentrator, which is assumed to have mirror reflection of millimeter waves in it, is designed to be shorter than conventional tapered waveguides of millimeter waves. A dimensionless design law of a concentrator is proposed based on geometric optics theory. Because the applicability of geometric optics theory is unclear, the ratio of its bore diameter to its wavelength was set as small compared to those in other possible applications. Then, the discrepancy between the designed and measured power reception was examined. Results show that the maximum discrepancy was as low as 7 % for the bore-to-wavelength ratio of 20 at the narrow end of the concentrator.

  11. A Novel High Sensitivity Sensor for Remote Field Eddy Current Non-Destructive Testing Based on Orthogonal Magnetic Field

    Directory of Open Access Journals (Sweden)

    Xiaojie Xu

    2014-12-01

    Full Text Available Remote field eddy current is an effective non-destructive testing method for ferromagnetic tubular structures. In view of conventional sensors’ disadvantages such as low signal-to-noise ratio and poor sensitivity to axial cracks, a novel high sensitivity sensor based on orthogonal magnetic field excitation is proposed. Firstly, through a three-dimensional finite element simulation, the remote field effect under orthogonal magnetic field excitation is determined, and an appropriate configuration which can generate an orthogonal magnetic field for a tubular structure is developed. Secondly, optimized selection of key parameters such as frequency, exciting currents and shielding modes is analyzed in detail, and different types of pick-up coils, including a new self-differential mode pick-up coil, are designed and analyzed. Lastly, the proposed sensor is verified experimentally by various types of defects manufactured on a section of a ferromagnetic tube. Experimental results show that the proposed novel sensor can largely improve the sensitivity of defect detection, especially for axial crack whose depth is less than 40% wall thickness, which are very difficult to detect and identify by conventional sensors. Another noteworthy advantage of the proposed sensor is that it has almost equal sensitivity to various types of defects, when a self-differential mode pick-up coil is adopted.

  12. The Impact of an Inquiry-Based Geoscience Field Course on Pre-service Teachers

    Science.gov (United States)

    Nugent, Gwen; Toland, Michael D.; Levy, Richard; Kunz, Gina; Harwood, David; Green, Denise; Kitts, Kathy

    2012-08-01

    The purpose of this quasi-experimental study was to determine the effects of a field-based, inquiry-focused course on pre-service teachers' geoscience content knowledge, attitude toward science, confidence in teaching science, and inquiry understanding and skills. The field-based course was designed to provide students with opportunities to observe, compare, and investigate geological structures in their natural environment and to gain an understanding of inquiry via hands-on learning activities designed to immerse students in authentic scientific investigation. ANCOVA and MANCOVA analyses examining differences in outcome measures between students in the field experience ( n = 25) and education students enrolled in the traditional, classroom-based course ( n = 37) showed that students in the field course generally had significantly higher scores. Results provide evidence of the value of the field and inquiry-based approach in helping pre-service teachers develop the needed skills and knowledge to create effective inquiry-based science lessons.

  13. Spare Parts Demand Analysis Method Based on Field Replaceable Unit

    Science.gov (United States)

    Zhu, Min; Xu, Zijian; Guo, Ming; Li, Biao

    2017-10-01

    It is based on the reliability of spare parts optimization modeling, and the influence of failure rate, fixability, importance and availability on spare parts reserves is added to the model, and the weight of each spare part is calculated by fuzzy analytic hierarchy process.

  14. Validity of selected cardiovascular field-based test among Malaysian ...

    African Journals Online (AJOL)

    Based on emerge obese problem among Malaysian, this research is formulated to validate published tests among healthy female adult. Selected test namely; 20 meter multi-stage shuttle run, 2.4km run test, 1 mile walk test and Harvard Step test were correlated with laboratory test (Bruce protocol) to find the criterion validity ...

  15. Mach's phenomenalism and the British reception of Mendelism.

    Science.gov (United States)

    Sloan, P R

    2000-12-01

    The assimilation of Mendel's paper into Britain took place in an Edwardian social context. This paper concentrates on the interplay of empirical and philosophical issues in this reception. A feature of the British reception of mendelism, not duplicated elsewhere, was the role of phenomenalist philosophies of science as developed by the physicist-mathematician and scientific methodologist Karl Pearson from the philosophical positions of Austrian physicist Ernst Mach and British mathematician William Clifford. Pearson's philosophy of science forms the background to his subsequent collaboration with the zoologist W.F.R. Weldon. In this collaborative work, Pearson developed powerful statistical techniques for analyzing Weldon's empirical data on organic variation. Pearson's statistical analysis of causation and his rejection of hidden entities and causes in the explanation of evolutionary change formed the philosophical component of this program. The arguments of Pearson and Weldon were first brought to bear against the pre-Mendel 'discontinuist' analyses of variation of William Bateson. The introduction of Mendel's paper into these empirical and methodological debates consequently resulted in mathematically sophisticated attacks on Mendel's claims by Pearson and Weldon. This paper summarizes this history and argues for the creative importance of this biometrical resistance to Mendelism.

  16. The public reception of the Research Assessment Exercise 1996.

    Directory of Open Access Journals (Sweden)

    Julian Warner

    1998-01-01

    Full Text Available This paper reviews the public reception of the Research Assessment Exercise 1996 (RAE from its announcement in December 1996 to the decline of discussion at end May 1997. A model for diffusion of the RAE is established which distinguishes extra-communal (or exoteric from intra-communal (or esoteric media. The different characteristics of each medium and the changing nature of the discussion over time are considered. Different themes are distinguished in the public reception of the RAE: the spatial distribution of research; the organisation of universities; disciplinary differences in understanding; a perceived conflict between research and teaching; the development of a culture of accountability; and analogies with the organisation of professional football. In conclusion, it is suggested that the RAE and its effects can be more fully considered from the perspective of scholarly communication and understandings of the development of knowledge than it has been by previous contributions in information science, which have concentrated on the possibility of more efficient implementation of existing processes. A fundamental responsibility for funding councils is also identified: to promote the overall health of university education and research, while establishing meaningful differentiations between units.

  17. Evidence of proceptive without receptive defeminization in male ferrets.

    Science.gov (United States)

    Baum, M J; Stockman, E R; Lundell, L A

    1985-08-01

    The latencies of groups of gonadectomized male and female ferrets to approach and interact with a sexually active stimulus male were measured after administration of estradiol benzoate (EB; 0, 5, 10, or 15 micrograms/kg) in adulthood. Receptive responsiveness to stud males was also assessed in these same ferrets during additional tests. Control female ferrets gonadectomized on Postnatal Day 35 displayed a dose-dependent reduction in approach latencies to the stud male which did not occur in control males castrated on Day 35. The approach latencies of males castrated on Postnatal Day 20 or Day 5 were intermediate between these two extremes. Equivalent dose-dependent reductions in approach latencies were observed in groups of ferrets ovariectomized on Day 5 and implanted sc with Silastic capsules containing either no hormone or different doses of testosterone over Postnatal Days 5-20 or 20-35. Equivalent dose-dependent increments in acceptance quotients were obtained in all groups of male and female ferrets following EB treatment. These results suggest that the capacity to display the proceptive, or appetitive, components of feminine sexual behavior is normally reduced in male ferrets as a consequence of the perinatal action of testicular hormones whereas receptive behavioral capacity is retained in males of this species.

  18. Arabinogalactan-protein secretion is associated with the acquisition of stigmatic receptivity in the apple flower

    OpenAIRE

    Losada Rodríguez, Juan Manuel; Herrero Romero, María

    2012-01-01

    Background and Aims Stigmatic receptivity plays a clear role in pollination dynamics; however, little is known about the factors that confer to a stigma the competence to be receptive for the germination of pollen grains. In this work, a developmental approach is used to evaluate the acquisition of stigmatic receptivity and its relationship with a possible change in arabinogalactan-proteins (AGPs). Methods Flowers of the domestic apple, Malus × domestica, were assessed for their capacity ...

  19. A.A.EVENT PLANNING - Catering Services For A Wedding Reception

    OpenAIRE

    Addison, Adelaide

    2012-01-01

    This project report focuses on planning the traditional wedding reception for a couple who are interested in having a western reception with an African traditional touch. That is a western African wedding reception. They are both Christians and have invited their church members as well as their family members to be part of their great celebration day. Since the couples and I are members of the same church, they heard of my established business through word of mouth and assign my wedding p...

  20. Receptive Vocabulary in Boys with Autism Spectrum Disorder: Cross-Sectional Developmental Trajectories

    OpenAIRE

    Kover, Sara T.; McDuffie, Andrea S.; Hagerman, Randi J.; Abbeduto, Leonard

    2013-01-01

    In light of evidence that receptive language may be a relative weakness for individuals with autism spectrum disorder (ASD), this study characterized receptive vocabulary profiles in boys with ASD using cross-sectional developmental trajectories relative to age, nonverbal cognition, and expressive vocabulary. Participants were 49 boys with ASD (4–11 years) and 80 typically developing boys (2–11 years). Receptive vocabulary, assessed with the Peabody Picture Vocabulary Test, was a weakness for...

  1. AGRICULTURAL FIELD IRRIGATION SOLUTION BASED ON VENTURI NOZZLE MODEL

    Directory of Open Access Journals (Sweden)

    ȘCHEAUA Fănel

    2016-11-01

    Full Text Available There are situations when the agricultural field irrigation requires water retrieved from the medium or deep groundwater reserves. For this solution submersible pumps are needed in order to take over the water from a certain depth and carry it to the surface to be stored in a tank or distributed directly to the irrigation plant. An alternative solution is represented by using a pumping system that can achieve a continuous water transport on a vertical direction from the source depth to the surface that comprises a centrifugal pump and a VENTURI nozzle positioned inside the well. In order to achieve this model a fluid driving circuit is required and special construction of the VENTURI tube by means of which the water is accelerated toward the surface. A 3D model of the VENTURI nozzle was built and analyzed with ANSYS CFX in order to highlight the operating parameters depending on the initially declared conditions. The obtained results are presented from the conducted analysis on the virtual model.

  2. Automatic Tooth Segmentation of Dental Mesh Based on Harmonic Fields

    Directory of Open Access Journals (Sweden)

    Sheng-hui Liao

    2015-01-01

    Full Text Available An important preprocess in computer-aided orthodontics is to segment teeth from the dental models accurately, which should involve manual interactions as few as possible. But fully automatic partition of all teeth is not a trivial task, since teeth occur in different shapes and their arrangements vary substantially from one individual to another. The difficulty is exacerbated when severe teeth malocclusion and crowding problems occur, which is a common occurrence in clinical cases. Most published methods in this area either are inaccurate or require lots of manual interactions. Motivated by the state-of-the-art general mesh segmentation methods that adopted the theory of harmonic field to detect partition boundaries, this paper proposes a novel, dental-targeted segmentation framework for dental meshes. With a specially designed weighting scheme and a strategy of a priori knowledge to guide the assignment of harmonic constraints, this method can identify teeth partition boundaries effectively. Extensive experiments and quantitative analysis demonstrate that the proposed method is able to partition high-quality teeth automatically with robustness and efficiency.

  3. [Welding arc temperature field measurements based on Boltzmann spectrometry].

    Science.gov (United States)

    Si, Hong; Hua, Xue-Ming; Zhang, Wang; Li, Fang; Xiao, Xiao

    2012-09-01

    Arc plasma, as non-uniform plasma, has complicated energy and mass transport processes in its internal, so plasma temperature measurement is of great significance. Compared with absolute spectral line intensity method and standard temperature method, Boltzmann plot measuring is more accurate and convenient. Based on the Boltzmann theory, the present paper calculates the temperature distribution of the plasma and analyzes the principle of lines selection by real time scanning the space of the TIG are measurements.

  4. Measurements of Electromagnetic Fields Emitted from Cellular Base Stations in

    Directory of Open Access Journals (Sweden)

    K. J. Ali

    2013-05-01

    Full Text Available With increasing the usage of mobile communication devices and internet network information, the entry of private telecommunications companies in Iraq has been started since 2003. These companies began to build up cellular towers to accomplish the telecommunication works but they ignore the safety conditions imposed for the health and environment that are considered in random way. These negative health effects which may cause a health risk for life beings and environment pollution. The aim of this work is to determine the safe and unsafe ranges and discuss damage caused by radiation emitted from Asia cell base stations in Shirqat city and discuses the best ways in which can be minimize its exposure level to avoid its negative health effects. Practical measurements of power density around base stations has been accomplished by using a radiation survey meter type (Radio frequency EMF Strength Meter 480846 in two ways. The first way of measurements has been accomplished at a height of 2 meters above ground for different distances from (0-300 meters .The second way is at a distance of 150 meters for different levels from (2-15 meters above ground level. The maximum measured power density is about (3 mW/m2. Results indicate that the levels of power density are far below the RF radiation exposure of USSR safety standards levels. And that means these cellular base station don't cause negative the health effect for life being if the exposure is within the acceptable international standard levels.

  5. Far Field Extrapolation from Near Field Interactions and Shielding Influence Investigations Based on a FE-PEEC Coupling Method

    Directory of Open Access Journals (Sweden)

    Gérard Meunier

    2013-03-01

    Full Text Available Regarding standards, it is well established that common mode currents are the main source of far field emitted by variable frequency drive (VFD-cable-motor associations. These currents are generated by the combination of floating potentials with stray capacitances between these floating potential tracks and the mechanical parts connected to the earth (the heatsink or cables are usual examples. Nowadays, due to frequency and power increases, the systematic compliance to EMC (ElectroMagnetic Compatibility becomes increasingly difficult and costly for industrials. As a consequence, there is a well-identified need to investigate practical and low cost solutions to reduce the radiated fields of VFD-cable-motor associations. A well-adapted solution is the shielding of wound components well known as the major source of near magnetic field. However, this solution is not convenient, it is expensive and may not be efficient regarding far field reduction. Optimizing the components placement could be a better and cheaper solution. As a consequence, dedicated tools have to be developed to efficiently investigate not easy comprehendible phenomena and finally to control EMC disturbances using component placement, layout geometry, shielding design if needed. However, none of the modeling methods usually used in industry complies with large frequency range and far field models including magnetic materials, multilayer PCBs, and shielding. The contribution of this paper is to show that alternatives regarding modeling solutions exist and can be used to get in-deep analysis of such complex structures. It is shown in this paper that near field investigations can give information on far field behavior. It is illustrated by an investigation of near field interactions and shielding influence using a FE-PEEC hybrid method. The test case combining a common mode filter with the floating potentials tracks of an inverter is based on an industrial and commercialized VFD. The

  6. Expressive and receptive language skills in preschool children from a socially disadvantaged area.

    Science.gov (United States)

    Ryan, Ashling; Gibbon, Fiona E; O'shea, Aoife

    2016-02-01

    Evidence suggests that children present with receptive language skills that are equivalent to or more advanced than expressive language skills. This profile holds true for typical and delayed language development. This study aimed to determine if such a profile existed for preschool children from an area of social deprivation and to investigate if particular language skills influence any differences found between expressive and receptive skills. Data from 187 CELF P2 UK assessments conducted on preschool children from two socially disadvantaged areas in a city in southern Ireland. A significant difference was found between Receptive Language Index (RLI) and Expressive Language Index (ELI) scores with Receptive scores found to be lower than Expressive scores. The majority (78.6%) of participants had a lower Receptive Language than Expressive score (RLI ELI), with very few (3.2%) having the same Receptive and Expressive scores (RLI = ELI). Scores for the Concepts and Following Directions (receptive) sub-test were significantly lower than for the other receptive sub tests, while scores for the Expressive Vocabulary sub-test were significantly higher than for the other expressive sub tests. The finding of more advanced expressive than receptive language skills in socially deprived preschool children is previously unreported and clinically relevant for speech-language pathologists in identifying the needs of this population.

  7. High sensitive LPFG magnetic field sensor based on dual-peak resonance

    Science.gov (United States)

    Gu, Zhengtian; Ling, Qiang; Lan, Jinlong; Gao, Kan

    2017-11-01

    A high sensitivity magnetic field sensor based on magnetic-fluid-clad LPFG structure with dual peak resonance is presented and experimentally investigated. Based on coupled mode theory, the sensing principle of this sensor is originated from the sensibility of the dual peak based LPFG to the environment refractive index. In experiment, a dual peak interval change was available to 38 nm with a magnetic field strength varying from 0 to 12 mT when the temperature was 17.3 °C, and the dual peak interval displays a cubic polynomial dependence with the magnetic field strength at the low field regime. The sensitivity of this sensor to the magnetic field can be available to 4.08 nm/mT, and it is one order and two orders of magnitude higher than that of the sensors based on MSM and SMS fiber structure, respectively. The novel sensor has many advantages of simple technology, structure stability and high sensitivity.

  8. Methods of evaluating human exposure to electromagnetic fields radiated from operating base stations in Korea.

    Science.gov (United States)

    Kim, Byung Chan; Choi, Hyung-Do; Park, Seong-Ook

    2008-10-01

    This article presents measurement methods used to determine the human exposure to electromagnetic fields radiated from operating base stations. In Korea, when evaluating the human exposure to electromagnetic fields from operating base stations, the measurement procedure is different between the following cases: in situ measurement and electromagnetic environment measurement. When performing an in situ measurement, compliance with human exposure limits is determined by the spatially averaged field value obtained within the space occupied by humans at one arbitrary position, but when performing an electromagnetic environment measurement, it is determined by the maximum value at the highest field position selected from several places.

  9. [Expectation of Brazilian nurses about the reception held at the primary health care].

    Science.gov (United States)

    Costa, Paula C Da; Francischetti-Garcia, Ana P Rigon; Pellegrino-Toledo, Vanessa

    2016-01-01

    To know the expectations of Brazilians nurses in relation to the reception held for them at the Primary Health Care. Method: This is a qualitative study based on the social phenomenology by Alfred Schutz. The nurses report that the host is something far from their reality, dependent on policy, management, population and physical structure of the workplace. The findings of this study showed that the reality of care performed by nurses in primary health care is characterized by calls for the evaluation of acute complaints, and that the solution to the host be ideal, providing changes in the relationship between him and the user they require far capabilities of its reality, which was called in this study magic output. It was evident that for nurses the reorganization of the host and their work process depends only on external factors to their actions, forgetting its commitment to provide a humanized care and based on the application of its relational competence.

  10. Computer-Based Procedures for Field Workers - Identified Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States); Le Blanc, Katya L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    The Idaho National Laboratory (INL) computer-based procedure (CBP) research team is exploring how best to design a CBP system that will deliver the intended benefits of increased efficiency and improved human performance. It is important to note that no “off-the-shelf” technology exists for the type of CBP system that is investigated and developed by the INL researchers. As more technology is integrated into the procedure process the importance of an appropriate and methodological approach to the design of the procedure system increases. Technological advancements offer great opportunities for efficiency and safety gains, however if the system is not designed correctly there is a large risk of unintentionally introducing new opportunities for human errors. The INL research team is breaking new ground in the area of CBPs with the prototype they have developed. Current electronic procedure systems are most commonly electronic versions of the paper-based procedures with hyperlinks to other procedures, limited user input functionality, and the ability to mark steps completed. These systems do not fully exploit the advantages digital technology. It is a part of the INL researchers’ role to develop and validate new CBP technologies that greatly increase the benefits of a CBP system to the nuclear industry.

  11. A comparison of receptive-expressive language profiles between toddlers with autism spectrum disorder and developmental language delay.

    Science.gov (United States)

    Seol, Kyeong In; Song, Seung Ha; Kim, Ka Lim; Oh, Seung Taek; Kim, Young Tae; Im, Woo Young; Song, Dong Ho; Cheon, Keun-Ah

    2014-11-01

    It is well known that expressive language impairment is commonly less severe than receptive language impairment in children with autism spectrum disorder (ASD). However, this result is based on experiments in Western countries with Western language scales. This study tries to find whether the result above is applicable for toddlers in a non-Western country; more specifically, in Korea with non-Western language scales. The participants were 166 toddlers aged between 20 months and 50 months who visited the clinic from December 2010 to January 2013. The number of toddlers diagnosed as ASD and developmental language delay (DLD) was 103 and 63, respectively. Language development level was assessed using Sequenced Language Scale for Infants (SELSI), a Korean language scale. Using SELSI, each group was divided into 3 sub-groups. Moreover, the group difference by age was observed by dividing them into three age groups. Chi-square test and linear-by-linear association was used for analysis. Receptive language ability of the DLD group was superior to that of the ASD group in all age groups. However, expressive language ability in both groups showed no difference in all age groups. A greater proportion of expressive dominant type was found in ASD. The 20-29 months group in ASD showed the largest proportion of expressive language dominant type in the three age groups, suggesting that the younger the ASD toddler is, the more severe the receptive language impairment is. These findings suggest that receptive-expressive language characteristics in ASD at earlier age could be useful in the early detection of ASD.

  12. Comparing methods for assessing receptive language skills in minimally verbal children and adolescents with autism spectrum disorders.

    Science.gov (United States)

    Plesa Skwerer, Daniela; Jordan, Samantha E; Brukilacchio, Briana H; Tager-Flusberg, Helen

    2016-07-01

    This research addresses the challenges of assessing receptive language abilities in minimally verbal children with autism spectrum disorder by comparing several adapted measurement tools: a standardized direct assessment of receptive vocabulary (i.e. Peabody Picture Vocabulary Test-4); caregiver report measures including scores on the Vineland-II Communication domain and a vocabulary questionnaire consisting of a list of words ranging from simple, developmentally early, to more advanced words expected to be understood by at least some older children and adolescents; an eye-tracking test of word comprehension, using a word-image pair matching paradigm similar to that often used in studies of infant language acquisition; and a computerized assessment using a touch screen for directly measuring word comprehension with the same stimuli used in the eye-tracking experiment. Results of this multiple-method approach revealed significant heterogeneity in receptive language abilities across participants and across assessment methods. Our findings underscore the need to find individualized approaches for capturing the potential for language comprehension of minimally verbal children with autism spectrum disorder who remain otherwise untestable, using several types of assessment that may include methods based on eye-tracking or touch-screen responding. © The Author(s) 2015.

  13. Two-microphone spatial filtering improves speech reception for cochlear-implant users in reverberant conditions with multiple noise sources.

    Science.gov (United States)

    Goldsworthy, Raymond L

    2014-10-20

    This study evaluates a spatial-filtering algorithm as a method to improve speech reception for cochlear-implant (CI) users in reverberant environments with multiple noise sources. The algorithm was designed to filter sounds using phase differences between two microphones situated 1 cm apart in a behind-the-ear hearing-aid capsule. Speech reception thresholds (SRTs) were measured using a Coordinate Response Measure for six CI users in 27 listening conditions including each combination of reverberation level (T60=0, 270, and 540 ms), number of noise sources (1, 4, and 11), and signal-processing algorithm (omnidirectional response, dipole-directional response, and spatial-filtering algorithm). Noise sources were time-reversed speech segments randomly drawn from the Institute of Electrical and Electronics Engineers sentence recordings. Target speech and noise sources were processed using a room simulation method allowing precise control over reverberation times and sound-source locations. The spatial-filtering algorithm was found to provide improvements in SRTs on the order of 6.5 to 11.0 dB across listening conditions compared with the omnidirectional response. This result indicates that such phase-based spatial filtering can improve speech reception for CI users even in highly reverberant conditions with multiple noise sources. © The Author(s) 2014.

  14. Assessing the Effectiveness of Holistic Multidimensional Treatment Model (Hojjati Model on Receptive and Expressive Language Skills in Autistic Children

    Directory of Open Access Journals (Sweden)

    Maryam Hojjati

    2017-05-01

    Full Text Available Background: Autism as part of the category called Autism spectrum disorder (ASD, is caused by disorders in brain and nervous network and characterized by defect in social behavior, language and cognition. This study aimed to investigate receptive and expressive language performance and the severity of the disorder in 30 children with autism aged 2-8 years who speak in Persian language. Materials and Methods In this cross-sectional study 30 children with autism were selected using random sampling method. The study tools included "The Childhood Autism Rating Scale (CARS", and "Newsha Developmental Scale (NDS" for assessing the receptive - expressive language skills. In order to assess the level of language impairment in subjects, the participants were divided into 5 groups with 6 people (considering the speaking ability including sign language and speech, with equal number of boys and girls (3 girls and 3 boys in each group. All of these children were evaluated by pediatric psychiatry, pediatric neurologist and pediatrician and were assessed according to the criteria for autism based on the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V. Eventually, the data were analyzed using descriptive and inferential statistics in SPSS version 16.0 software. Results The results showed that there was a significant difference between the mean (standard deviation and scores of receptive – expressive language skills in autistic subjects in each of the groups (P

  15. Two-Microphone Spatial Filtering Improves Speech Reception for Cochlear-Implant Users in Reverberant Conditions With Multiple Noise Sources

    Directory of Open Access Journals (Sweden)

    Raymond L. Goldsworthy

    2014-10-01

    Full Text Available This study evaluates a spatial-filtering algorithm as a method to improve speech reception for cochlear-implant (CI users in reverberant environments with multiple noise sources. The algorithm was designed to filter sounds using phase differences between two microphones situated 1 cm apart in a behind-the-ear hearing-aid capsule. Speech reception thresholds (SRTs were measured using a Coordinate Response Measure for six CI users in 27 listening conditions including each combination of reverberation level (T60 = 0, 270, and 540 ms, number of noise sources (1, 4, and 11, and signal-processing algorithm (omnidirectional response, dipole-directional response, and spatial-filtering algorithm. Noise sources were time-reversed speech segments randomly drawn from the Institute of Electrical and Electronics Engineers sentence recordings. Target speech and noise sources were processed using a room simulation method allowing precise control over reverberation times and sound-source locations. The spatial-filtering algorithm was found to provide improvements in SRTs on the order of 6.5 to 11.0 dB across listening conditions compared with the omnidirectional response. This result indicates that such phase-based spatial filtering can improve speech reception for CI users even in highly reverberant conditions with multiple noise sources.

  16. Estimation of Potential Interference Immunity of Radio Reception with Spatial Signal Processing in Mutipath Radio-Communication Channels. Part II. Meter and Decimeter Ranges

    Science.gov (United States)

    Lvov, A. V.; Metelev, S. L.

    2016-11-01

    We propose simulation models for estimating the interference immunity of radio reception using the spatial processing of signals in the airborne and ground-based communication channels of the meter and decimeter wavelength ranges. The ultimate achievable interference immunity under various radio-wave propagation conditions is studied.

  17. In vitro receptivity of carbonate rocks to endolithic lichen-forming aposymbionts.

    Science.gov (United States)

    Favero-Longo, Sergio E; Borghi, Alessandro; Tretiach, Mauro; Piervittori, Rosanna

    2009-10-01

    Sterile cultured isolates of lichen-forming aposymbionts have not yet been used to investigate lichen-rock interactions under controlled conditions. In this study mycobionts and photobiont of the endolithic lichens Bagliettoa baldensis and Bagliettoa marmorea were isolated and inoculated with coupons of one limestone and four marbles commonly employed in the Cultural Heritage framework. After one year of incubation, microscopic observations of polished cross-sections were performed to verify if the typical colonization patterns observed in the field may be reproduced in vitro and to evaluate the receptivity of the five lithotypes to endolithic lichens. The mycobionts of the two species developed both on the surface of and within all the lithotypes, showing different penetration pathways which depend on mineralogical and structural features and highlight different receptivity. By contrast, algae inoculated with the coupons did not penetrate them. Observations suggest that the hyphal penetration along intrinsic discontinuities of rocks is a relatively fast phenomenon when these organisms are generally considered as slow-growing. Samples from limestone outcrops and abandoned marble quarries, colonized by the same species or other representatives of Verrucariaceae, showed penetration pathways intriguingly similar to those reproduced in vitro and highlighted that lichen-driven erosion processes only increase the availability of hyphal passageways after a long-term colonization. These results show that in vitro incubation of sterile cultured lichen-forming ascomycetes with rock coupons is a practicable experimental system to investigate the lichen-rock interactions under controlled conditions and, together with analysis in situ, may support decisions on conservative treatments of historical and cultural significant stone substrata.

  18. Ultrasound Molecular Imaging of Vascular Endothelial Growth Factor Receptor 2 Expression for Endometrial Receptivity Evaluation

    Science.gov (United States)

    Liu, Hongmei; Chen, Yihan; Yan, Fei; Han, Xiaohua; Wu, Junru; Liu, Xin; Zheng, Hairong

    2015-01-01

    Purpose: Ultrasound (US) molecular imaging by examining the expression of vascular endothelial growth factor receptor 2 (VEGFR2) on uterus vascular endothelium was applied to evaluate the endometrial receptivity. Methods: VEGFR2-targeted ultrasound contrast agents (UCA) and the control UCA (without VEGFR2) were prepared and characterized. Adhesion experiment in vitro was performed with mouse microvascular endothelial cells (bEnd.3) and the ratio of the number of UCA to that of cells at the same field was compared. In vivo study, randomized boluses of targeted or control UCA were injected into the animals of non-pregnancy (D0), pregnancy on day 2 (D2) and day 4 (D4), respectively. Sonograms were acquired by an ultrasound equipment with a 40-MHz high-frequency transducer (Vevo 2100; VisualSonics, Toronto, Canada). The ultrasonic imaging signals were quantified as the video intensity amplitudes generated by the attachment of VEGFR2-targeted UCA. Immunoblotting and immunofluorescence assays were used for confirmation of VEGFR2 expression. Results: Our results showed that VEGFR2-targeted UCA could bind to bEnd.3 cells with significantly higher affinity than the control UCA (9.8 ± 1.0 bubbles/cell versus 0.7 ± 0.3 bubbles/cell, P 0.05). Moreover, D4 mice showed the highest video intensity amplitude, indicating the highest VEGFR2 expression when compared with D2 and D0 mice (P < 0.01). This was further confirmed by our immunoblotting and immunofluorescence experiments. Conclusion: Ultrasound molecular imaging with VEGFR2-targeted UCA may be used for noninvasive evaluation of endometrial receptivity in murine models. PMID:25553109

  19. Avian survey and field guide for Osan Air Base, Korea.

    Energy Technology Data Exchange (ETDEWEB)

    Levenson, J.

    2006-12-05

    This report summarizes the results of the avian surveys conducted at Osan Air Base (AB). This ongoing survey is conducted to comply with requirements of the Environmental Governing Standards (EGS) for the Republic of Korea, the Integrated Natural Resources Management Plan (INRMP) for Osan AB, and the 51st Fighter Wing's Bird Aircraft Strike Hazard (BASH) Plan. One hundred ten bird species representing 35 families were identified and recorded. Seven species are designated as Natural Monuments, and their protection is accorded by the Korean Ministry of Culture and Tourism. Three species appear on the Korean Association for Conservation of Nature's (KACN's) list of Reserved Wild Species and are protected by the Korean Ministry of Environment. Combined, ten different species are Republic of Korea (ROK)-protected. The primary objective of the avian survey at Osan AB was to determine what species of birds are present on the airfield and their respective habitat requirements during the critical seasons of the year. This requirement is specified in Annex J.14.c of the 51st Fighter BASH Plan 91-212 (51 FW OPLAN 91-212). The second objective was to initiate surveys to determine what bird species are present on Osan AB throughout the year and from the survey results, determine if threatened, endangered, or other Korean-listed bird species are present on Osan AB. This overall census satisfies Criterion 13-3.e of the EGS for Korea. The final objective was to formulate management strategies within Osan AB's operational requirements to protect and enhance habitats of known threatened, endangered, and ROK-protected species in accordance with EGS Criterion 13-3.a that are also favorable for the reproduction of indigenous species in accordance with the EGS Criterion 13-3.h.

  20. Avian Field guide and checklist for Kunsan Air Base, Korea.

    Energy Technology Data Exchange (ETDEWEB)

    Levenson, J. B.; Environmental Assessment

    2005-11-15

    This report summarizes the results of the avian surveys conducted at Kunsan Air Base (AB). This on-going survey is conducted to comply with requirements of the Environmental Governing Standards (EGS) for the Republic of Korea, the Integrated Natural Resources Management Plan (INRMP) for Kunsan AB, and the 8th Fighter Wing's Bird Aircraft Strike Hazard (BASH) Plan. One hundred sixteen bird species representing 34 families were identified and recorded. Seven species are designated as Cultural Property Monuments, and their protection is accorded by the Korean Ministry of Culture and Tourism. Six species appear on the Korean Association for Conservation of Nature's(KACN's) list of Reserved Wild Species and are protected by the Korean Ministry of Environment. Combined, only ten different species are Republic of Korea (ROK)-protected because the Eurasian Spoonbill, Peregrine Falcon, and Eurasian Oystercatcher are listed by both agencies. The primary objective of the avian survey at Kunsan AB was to determine what species of birds are present on the airfield and their respective habitat requirements during the critical seasons of the year. This requirement is specified in Annex C.4.a.(1-4) of the 8th Fighter Wing BASH Plan(8FWOPLAN 91-202). The second objective was to initiate surveys to determine what bird species are present on Kunsan AB throughout the year, and from the survey results determine if threatened, endangered, or other Korean-listed bird species are present on Kunsan AB. This overall census satisfies Criterion 13-3.e of the EGS for Korea. The final objective was to formulate management strategies within Kunsan AB's operational requirements to protect and enhance habitats of known threatened, endangered, and ROK-protected species in accordance with EGS Criterion 13-3.a and also that are favorable for the reproduction of indigenous species in accordance with the EGS Criterion 13-3.h.

  1. Overview of identification methods of mechanical parameters based on full-field measurements

    OpenAIRE

    Avril, Stéphane; Bonnet, Marc; Bretelle, Anne Sophie; Grediac, Michel; Hild, François; Ienny, Patrick; Latourte, Felix; Lemosse, Didier; Pagano, Stéphane; Pagnacco, Emmanuel; Pierron, Fabrice

    2008-01-01

    This article reviews recently developed methods for constitutive parameter identification based on kinematic full-field measurements, namely the finite element model updating method (FEMU), the constitutive equation gap method (CEGM), the virtual fields method (VFM), the equilibrium gap method (EGM) and the reciprocity gap method (RGM). Their formulation and underlying principles are presented and discussed. These identification techniques are then applied to full-field experimental data obta...

  2. Heterogeneous Web Data Extraction Algorithm Based On Modified Hidden Conditional Random Fields

    OpenAIRE

    Cui Cheng

    2014-01-01

    As it is of great importance to extract useful information from heterogeneous Web data, in this paper, we propose a novel heterogeneous Web data extraction algorithm using a modified hidden conditional random fields model. Considering the traditional linear chain based conditional random fields can not effectively solve the problem of complex and heterogeneous Web data extraction, we modify the standard hidden conditional random fields in three aspects, which are 1) Using the hidden Markov mo...

  3. Gesture Recognition using Latent-Dynamic based Conditional Random Fields and Scalar Features

    Science.gov (United States)

    Yulita, I. N.; Fanany, M. I.; Arymurthy, A. M.

    2017-02-01

    The need for segmentation and labeling of sequence data appears in several fields. The use of the conditional models such as Conditional Random Fields is widely used to solve this problem. In the pattern recognition, Conditional Random Fields specify the possibilities of a sequence label. This method constructs its full label sequence to be a probabilistic graphical model based on its observation. However, Conditional Random Fields can not capture the internal structure so that Latent-based Dynamic Conditional Random Fields is developed without leaving external dynamics of inter-label. This study proposes the use of Latent-Dynamic Conditional Random Fields for Gesture Recognition and comparison between both methods. Besides, this study also proposes the use of a scalar features to gesture recognition. The results show that performance of Latent-dynamic based Conditional Random Fields is not better than the Conditional Random Fields, and scalar features are effective for both methods are in gesture recognition. Therefore, it recommends implementing Conditional Random Fields and scalar features in gesture recognition for better performance

  4. Genetic influences on receptive joint attention in chimpanzees (Pan troglodytes)

    DEFF Research Database (Denmark)

    Hopkins, William D; Keebaugh, Alaine C; Reamer, Lisa A

    2014-01-01

    Despite their genetic similarity to humans, our understanding of the role of genes on cognitive traits in chimpanzees remains virtually unexplored. Here, we examined the relationship between genetic variation in the arginine vasopressin V1a receptor gene (AVPR1A) and social cognition in chimpanze....... The collective findings show that AVPR1A polymorphisms are associated with individual differences in performance on a receptive joint attention task in chimpanzees.......Despite their genetic similarity to humans, our understanding of the role of genes on cognitive traits in chimpanzees remains virtually unexplored. Here, we examined the relationship between genetic variation in the arginine vasopressin V1a receptor gene (AVPR1A) and social cognition in chimpanzees...

  5. Sensing and Classifying Impairments of GPS Reception on Mobile Devices

    DEFF Research Database (Denmark)

    Blunck, Henrik; Kjærgaard, Mikkel Baun; Toftegaard, Thomas Skjødeberg

    2011-01-01

    Positioning using GPS receivers is a primary sensing modality in many areas of pervasive computing. However, previous work has not considered how people’s body impacts the availability and accuracy of GPS positioning and for means to sense such impacts. We present results that the GPS performance...... signal statistics. To help both users as well as application systems in understanding and mitigating body and environment-induced effects, we propose a method for sensing the current sources of GPS reception impairment in terms of body, urban and indoor conditions. We present results that show...... degradation on modern smart phones for different hand grip styles and body placements can cause signal strength drops as high as 10-16 dB and double the positioning error. Furthermore, existing phone applications designed to help users identify sources of GPS performance impairment are restricted to show raw...

  6. Translation and reception of Italo Calvino in China

    Directory of Open Access Journals (Sweden)

    Ting Zhou

    2017-07-01

    Full Text Available Calvino's works arrived in China surprisingly early. The first translated texts date back to the Fifties, when the writer, in his early thirties, was at the beginning of his career. The Chinese version is not a direct translation of the original texts of Calvino, but an indirect translation. This surprisingly early interest is followed by a long period of silence that goes from the second half of the Sixties until the end of the Seventies. The article will try to analyze the first translations of Calvino’s works published in China and to outline the reception of Calvino’s works in modern China in the last several decades. The contextual analysis is aimed to see the relationship between the translations and the historical and ideological context in which they were conceived.

  7. Peripheral auditory processing and speech reception in impaired hearing

    DEFF Research Database (Denmark)

    Strelcyk, Olaf

    One of the most common complaints of people with impaired hearing concerns their difficulty with understanding speech. Particularly in the presence of background noise, hearing-impaired people often encounter great difficulties with speech communication. In most cases, the problem persists even...... if reduced audibility has been compensated for by hearing aids. It has been hypothesized that part of the difficulty arises from changes in the perception of sounds that are well above hearing threshold, such as reduced frequency selectivity and deficits in the processing of temporal fine structure (TFS......) at the output of the inner-ear (cochlear) filters. The purpose of this work was to investigate these aspects in detail. One chapter studies relations between frequency selectivity, TFS processing, and speech reception in listeners with normal and impaired hearing, using behavioral listening experiments. While...

  8. An Exploration of the System Dynamics Field : A Model-Based Policy Analysis

    NARCIS (Netherlands)

    Rose, A.C.

    2014-01-01

    This report presents a first look study at the field of System Dynamics. The objective of the study is to perform a model-based policy analysis in order to investigate the future advancement of the System Dynamics field. The aim of this investigation is to determine what this advancement should look

  9. Educating Future Leaders of the Sport-Based Youth Development Field

    Science.gov (United States)

    Whitley, Meredith A.; McGarry, Jennifer Bruening; Martinek, Thomas; Mercier, Kevin; Quinlan, Melissa

    2017-01-01

    In recent years, a substantial surge has occurred in the number of initiatives, events and organizations focused on using sport as a tool for development, peacebuilding and humanitarian efforts. This has created a growing need for educated leaders in the sport-based youth development field as the job market in this field continues to expand. The…

  10. High-field Faraday rotation in II-VI-based semimagnetic semiconductors

    NARCIS (Netherlands)

    Savchuk, AI; Fediv, [No Value; Nikitin, PI; Perrone, A; Tatzenko, OM; Platonov, VV

    The effects of d-d exchange interaction have been studied by measuring high-field Faraday rotation in II-VI-based semimagnetic semiconductors. For Cd1-xMnxTe crystals with x = 0.43 and at room temperature a saturation in magnetic field dependence of the Faraday rotation has been observed. In the

  11. Wide field of view tabletop light field display based on piece-wise tracking and off-axis pickup

    Science.gov (United States)

    Zhu, Yanhong; Sang, Xinzhu; Yu, Xunbo; Wang, Peng; Xing, Shujun; Chen, Duo; Yan, Binbin; Wang, Kuiru; Yu, Chongxiu

    2017-11-01

    A wide field of view (FOV) tabletop light field display (LFD) based on piece-wise tracking and off-axis pickup is presented to display the floating three-dimensional (3D) scene, which is 360°surrounding viewable. The demonstrated LFD is specially designed with an integral imaging display (IID) with 83 × 83 viewpoints and a full-parallax holographic functional screen (HFS). To improve the FOV, a piece-wise tracking based FOV enhancement method is proposed. The relationship between the viewing zone and the elemental images (EIs) is formulated. A ray-tracing based method using off-axis pickup instead of parallel pickup directly is adopted to render the 3D scene to EIs. Then the piece-wise tracking method of varying the viewing zone by placing the EIs according to the position of viewer is analyzed. The floating 3D scene with a FOV of 70° × 70°is experimentally demonstrated with a good 3D perception.

  12. Field performance of bacteria-based repair system : Pilot study in a parking garage

    NARCIS (Netherlands)

    Wiktor, V.A.C.; Jonkers, H.M.

    2015-01-01

    This paper presents the field performance in a parking garage of the recently developed bacteria-based repair system for concrete. This liquid-based repair system aims at the sealing of cracks and decrease of the porosity due to the production of a calcium-based biomineral. The system combines

  13. Socioemotional competence, self-perceptions, and receptive vocabulary in shy canadian children

    Directory of Open Access Journals (Sweden)

    Sandra Bosacki

    2012-06-01

    Full Text Available Given existing gendered stereotypic assumptions regarding shyness and children’s school competencies, this study explored relations among socioemotional competencies, self-perceptions, and receptive vocabulary in shy children. Ninety-one Canadian children (52 girls, 39 boys; 5-8 years were classified as shy (n = 26 based on teachers’ behavioural ratings (n = 8, and completed selfperception and vocabulary measures. Compared to their non-shy peers, shy children reported lower levels of self-worth, and were rated by their teachers as more aggressive. Shy girls scored the lowest on the vocabulary task, and received the highest teacher emotional competence ratings. Shy boys scored the highest on the vocabulary task, and received the lowest emotionally competence ratings. Gender-role stereotypes and shyness and their educational implications are discussed.

  14. Socioemotional Competence, Self-Perceptions, and Receptive Vocabulary in Shy Canadian Children

    Directory of Open Access Journals (Sweden)

    Sandra BOSACKI

    2012-01-01

    Full Text Available Given existing gendered stereotypic assumptions regarding shyness and children’s schoolcompetencies, this study explored relations among socioemotional competencies, self-perceptions,and receptive vocabulary in shy children. Ninety-one Canadian children (52 girls, 39 boys; 5-8 yearswere classified as shy (n = 26 based on teachers’ behavioural ratings (n = 8, and completed selfperceptionand vocabulary measures. Compared to their non-shy peers, shy children reported lowerlevels of self-worth, and were rated by their teachers as more aggressive. Shy girls scored the loweston the vocabulary task, and received the highest teacher emotional competence ratings. Shy boysscored the highest on the vocabulary task, and received the lowest emotionally competence ratings.Gender-role stereotypes and shyness and their educational implications are discussed.

  15. Investigation on stresses of superconductors under pulsed magnetic fields based on multiphysics model

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaobin, E-mail: yangxb@lzu.edu.cn; Li, Xiuhong; He, Yafeng; Wang, Xiaojun; Xu, Bo

    2017-04-15

    Highlights: • The differential equation including temperature and magnetic field was derived for a long cylindrical superconductor. • Thermal stress and electromagnetic stress were studied at the same time under pulse field magnetizing. • The distributions of the magnetic field, the temperature and stresses are studied and compared for two pulse fields of the different duration. • The Role thermal stress and electromagnetic stress play in the process of pulse field magnetizing is discussed. - Abstract: A multiphysics model for the numerical computation of stresses, trapped field and temperature distribution of a infinite long superconducting cylinder is proposed, based on which the stresses, including the thermal stresses and mechanical stresses due to Lorentz force, and trapped fields in the superconductor subjected to pulsed magnetic fields are analyzed. By comparing the results under pulsed magnetic fields with different pulse durations, it is found that the both the mechanical stress due to the electromagnetic force and the thermal stress due to temperature gradient contribute to the total stress level in the superconductor. For pulsed magnetic field with short durations, the thermal stress is the dominant contribution to the total stress, because the heat generated by AC-loss builds up significant temperature gradient in such short durations. However, for a pulsed field with a long duration the gradient of temperature and flux, as well as the maximal tensile stress, are much smaller. And the results of this paper is meaningful for the design and manufacture of superconducting permanent magnets.

  16. Criterion-related validity of field-based muscular fitness tests in youth.

    Science.gov (United States)

    Artero, E G; España-Romero, V; Castro-Piñero, J; Ruiz, J; Jiménez-Pavón, D; Aparicio, V; Gatto-Cardia, M; Baena, P; Vicente-Rodríguez, G; Castillo, M J; Ortega, F B

    2012-06-01

    The purpose of the present study was to analyze the association between isokinetic strength and field-based muscular fitness tests in youth. One hundred twenty-six adolescents (14.4±1.7 y) participated in the study. Upper and lower body isokinetic strength were measured at preset angular velocities of 90 º/s and 60 º/s, respectively. Muscular fitness was also assessed by means of field-based tests: handgrip strength, bent and extended arm hang tests, standing long jump, squat jump, countermovement jump and Abalakov jump. Height, weight and skinfold thickness were used to estimate body composition. All field-based tests were significantly associated with isokinetic peak torque and power (Pvalid field-based muscular fitness tests when compared to isokinetic strength. These tests can be useful to assess muscular fitness in young people when laboratory methods are not feasible.

  17. Electrically Injected Polariton Lasing from a GaAs-Based Microcavity under Magnetic Field

    KAUST Repository

    Bhattacharya, Pallab

    2012-01-01

    Suppression of relaxation bottleneck and subsequent polariton lasing is observed in a GaAs-based microcavity under the application of a magnetic field. The threshold injection current density is 0.32 A/cm2 at 7 Tesla.

  18. CHEMICALLY MODIFIED FIELD-EFFECT TRANSISTORS - POTENTIOMETRIC AG+ SELECTIVITY OF PVC MEMBRANES BASED ON MACROCYCLIC THIOETHERS

    NARCIS (Netherlands)

    BRZOZKA, Z; COBBEN, PLHM; REINHOUDT, DN; EDEMA, JJH; KELLOGG, RM

    1993-01-01

    A chemically modified field-effect transistor (CHEMFET) with satisfactory Ag+ selectivity is described. The potentiometric Ag+ selectivities of CHEMFETs with plasticized PVC membranes based on macrocyclic thioethers have been determined. All the macrocyclic thioethers tested showed silver response

  19. A Field-Based Aquatic Life Benchmark for Conductivity in Central Appalachian Streams (Final Report)

    Science.gov (United States)

    EPA announced the availability of the final report, A Field-Based Aquatic Life Benchmark for Conductivity in Central Appalachian Streams. This report describes a method to characterize the relationship between the extirpation (the effective extinction) of invertebrate g...

  20. Establishing a Competency Field-Based Program of Reading Education: Essential Elements of Administrative Planning.

    Science.gov (United States)

    Blair, Charles W.

    1979-01-01

    Identifies essential aspects of administrative planning that must be considered when moving from a traditional reading preservice education program to a competency, field-based model of instruction. (TJ)

  1. Effective Strategies for Turning Receptive Vocabulary into Productive Vocabulary in EFL Context

    Science.gov (United States)

    Faraj, Avan Kamal Aziz

    2015-01-01

    Vocabulary acquisition has been a main concern of EFL English teachers and learners. There have been tons of research to examine the student's level of receptive vocabulary and productive vocabulary, but no research has conducted on how turning receptive vocabulary into productive vocabulary. This study has reported the impact of the teaching…

  2. Regulation regarding the reception of the construction works and the corresponding installations in Romania

    Directory of Open Access Journals (Sweden)

    Simona Chirică

    2017-12-01

    Full Text Available The new Regulation regarding the reception of construction works and corresponding installations, approved by Government's Decision no. 347/2017 (“Regulation 2017” has general applicability for all construction works for which there is an obligation to obtain a building permit. Regulation 2017 brings significant changes and clarifications expected by the real estate sector regarding: (i the composition of the commissions involved in the reception procedure, (ii the role of the site supervisor who thus gains significant participation in the reception procedure, and (iii the participation of the public authorities' representatives at the reception, having the veto right on the decision of the reception commission upon the completion of the construction works. Another element of novelty brought by Regulation 2017 is the possibility to do the reception upon the completion of the construction works, respectively the final reception for parts / objectives / sectors of or from the building, if they are distinct/ independent from a physical and functional point of view. Thus, the new regulation facilitates the procedure of authorizing investment objectives and the costs of the process. The partial reception is another innovation brought by the Regulation 2017 in support of the investor, who can thus take over a part of the construction, at a certain stage, and obtain its registration with the Land Book.

  3. Asynchronous development of stigmatic receptivity in the pear (Pyrus communis; Rosaceae) flower.

    Science.gov (United States)

    Sanzol, Javier; Rallo, Pilar; Herrero, María

    2003-01-01

    While stigma anatomy is well documented for a good number of species, little information is available on the acquisition and cessation of stigmatic receptivity. The aim of this work is to characterize the development of stigma receptivity, from anthesis to stigma degeneration, in the pentacarpellar pear (Pyrus communis) flower. Stigma development and stigmatic receptivity were monitored over two consecutive years, as the capacity of the stigmas to offer support for pollen germination and pollen tube growth. In an experiment where hand pollinations were delayed for specified times after anthesis, three different stigmatic developmental stages could be observed: (1) immature stigmas, which allow pollen adhesion but not hydration; (2) receptive stigmas, which allow proper pollen hydration and germination; and (3) degenerated stigmas, in which pollen hydrates and germinates properly, but pollen tube growth is impaired soon after germination. This developmental characterization showed that stigmas in different developmental stages coexist within a flower and that the acquisition and cessation of stigmatic receptivity by each carpel occur in a sequential manner. In this way, while the duration of stigmatic receptivity for each carpel is rather short, the flower has an expanded receptive period. This asynchronous period of receptivity for the different stigmas of a single flower is discussed as a strategy that could serve to maximize pollination resources under unreliable pollination conditions.

  4. The effectiveness of correcting codes in reception in the whole in additive normal white noise

    Science.gov (United States)

    Shtarkov, Y. M.

    1974-01-01

    Some possible criteria for estimating the effectiveness of correcting codes are presented, and the energy effectiveness of correcting codes is studied for symbol-by-symbol reception. Expressions for the energetic effectiveness of binary correcting codes for reception in the whole are produced. Asymptotic energetic effectiveness and finite signal/noise ratio cases are considered.

  5. Effects of Serial and Concurrent Training on Receptive Identification Tasks: A Systematic Replication

    Science.gov (United States)

    Wunderlich, Kara L.; Vollmer, Timothy R.

    2017-01-01

    The current study compared the use of serial and concurrent methods to train multiple exemplars when teaching receptive language skills, providing a systematic replication of Wunderlich, Vollmer, Donaldson, and Phillips (2014). Five preschoolers diagnosed with developmental delays or autism spectrum disorders were taught to receptively identify…

  6. Unaccompanied adolescents seeking asylum: Poorer mental health under a restrictive reception

    NARCIS (Netherlands)

    Reijneveld, S.A.; Boer, J.B.de; Bean, T.; Korfker, D.G.

    2005-01-01

    We assessed the effects of a stringent reception policy on the mental health of unaccompanied adolescent asylum seekers by comparing the mental health of adolescents in a restricted campus reception setting and in a setting offering more autonomy (numbers [response rates]: 69 [93%] and 53 [69%],

  7. Monstrosities and Twitterings: A Note on the Early Reception of Aristotle's Posterior Analytics

    DEFF Research Database (Denmark)

    Bloch, David

    2010-01-01

    En kort undersøgelse af et problem i den tidligere reception af Aristoteles' Analytica Posteriora i forbindelse med de første latinske oversættelser.......En kort undersøgelse af et problem i den tidligere reception af Aristoteles' Analytica Posteriora i forbindelse med de første latinske oversættelser....

  8. An Examination of College Students' Receptiveness to Alcohol-Related Information and Advice

    Science.gov (United States)

    Leahy, Matthew M.; Jouriles, Ernest N.; Walters, Scott T.

    2013-01-01

    This project examined the reliability and validity of a newly developed measure of college students' receptiveness to alcohol related information and advice. Participants were 116 college students who reported having consumed alcohol at some point in their lifetime. Participants completed a measure of receptiveness to alcohol-related…

  9. Receptive Vocabulary in Boys with Autism Spectrum Disorder: Cross-Sectional Developmental Trajectories

    Science.gov (United States)

    Kover, Sara T.; McDuffie, Andrea S.; Hagerman, Randi J.; Abbeduto, Leonard

    2013-01-01

    In light of evidence that receptive language may be a relative weakness for individuals with autism spectrum disorder (ASD), this study characterized receptive vocabulary profiles in boys with ASD using cross-sectional developmental trajectories relative to age, nonverbal cognition, and expressive vocabulary. Participants were 49 boys with ASD…

  10. Technological Development and Its Impact on Student Reception of a Campus Radio

    Science.gov (United States)

    Mohamed, Shafizan; Wok, Saodah; Lahabou, Mahaman

    2018-01-01

    In 2011, a study was conducted to look at students' reception of IIUM.FM, a newly launched online campus radio. Using the Technological Acceptance Model (TAM), the study found that factors such as perceived ease of use, perceived usefulness, and attitude highly influenced audience reception of the online radio. In 2016, a corresponding study,…

  11. Genome-Wide Association Study of Receptive Language Ability of 12-Year-Olds

    Science.gov (United States)

    Harlaar, Nicole; Meaburn, Emma L.; Hayiou-Thomas, Marianna E.; Davis, Oliver S. P.; Docherty, Sophia; Hanscombe, Ken B.; Haworth, Claire M. A.; Price, Thomas S.; Trzaskowski, Maciej; Dale, Philip S.; Plomin, Robert

    2014-01-01

    Purpose: Researchers have previously shown that individual differences in measures of receptive language ability at age 12 are highly heritable. In the current study, the authors attempted to identify some of the genes responsible for the heritability of receptive language ability using a "genome-wide association" approach. Method: The…

  12. The Qualitative and Numerical Analysis of the Cosmological Model Based on Phantom Scalar Field with Self

    CERN Document Server

    Ignat'ev, Yu G

    2016-01-01

    In this paper we investigate the asymptotic behavior of the cosmological model based on phantom scalar field on the ground of qualitative analysis of the system of the cosmological model's differential equations and show that as opposed to models with classical scalar field, such models have stable asymptotic solutions with constant value of the potential both in infinite past and infinite future. We also develop numerical models of the cosmological evolution models with phantom scalar field in this paper. {\\bf keywords}: cosmological model, phantom scalar field, quality analysis, asymptotic behavior, numerical simulation, numerical gravitation.\\\\ {\\bf PACS}: 04.20.Cv, 98.80.Cq, 96.50.S 52.27.Ny

  13. Terahertz detection of magnetic field-driven topological phase transition in HgTe-based transistors

    Energy Technology Data Exchange (ETDEWEB)

    Kadykov, A. M. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, Universite Montpellier, 34095 Montpellier (France); Institute for Physics of Microstructures, Russian Academy of Sciences, GSP-105, Nizhny Novgorod 603950 (Russian Federation); Teppe, F., E-mail: frederic.teppe@univ-montp2.fr; Consejo, C.; Ruffenach, S.; Marcinkiewicz, M.; Desrat, W.; Dyakonova, N.; Knap, W. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221, Universite Montpellier, 34095 Montpellier (France); Viti, L.; Vitiello, M. S. [NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, I-56127 Pisa (Italy); Krishtopenko, S. S.; Morozov, S. V.; Gavrilenko, V. I. [Institute for Physics of Microstructures, Russian Academy of Sciences, GSP-105, Nizhny Novgorod 603950 (Russian Federation); Lobachevsky State University, 23 Prospekt Gagarina, 603950 Nizhny Novgorod (Russian Federation); Mikhailov, N. N.; Dvoretsky, S. A. [Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, pr. Akademika Lavrent' eva 13, Novosibirsk 630090 (Russian Federation)

    2015-10-12

    We report on terahertz photoconductivity under magnetic field up to 16 T of field effect transistor based on HgTe quantum well (QW) with an inverted band structure. We observe pronounced cyclotron resonance and Shubnikov-de Haas-like oscillations, indicating a high mobility electron gas in the transistor channel. We discover that nonlinearity of the transistor channel allows for observation of characteristic features in photoconductivity at critical magnetic field corresponding to the phase transition between topological quantum spin Hall and trivial quantum Hall states in HgTe QW. Our results pave the way towards terahertz topological field effect transistors.

  14. Unipolar and Bipolar High-Magnetic-Field Sensors Based on Surface Acoustic Wave Resonators

    Science.gov (United States)

    Polewczyk, V.; Dumesnil, K.; Lacour, D.; Moutaouekkil, M.; Mjahed, H.; Tiercelin, N.; Petit Watelot, S.; Mishra, H.; Dusch, Y.; Hage-Ali, S.; Elmazria, O.; Montaigne, F.; Talbi, A.; Bou Matar, O.; Hehn, M.

    2017-08-01

    While surface acoustic wave (SAW) sensors have been used to measure temperature, pressure, strains, and low magnetic fields, the capability to measure bipolar fields and high fields is lacking. In this paper, we report magnetic surface acoustic wave sensors that consist of interdigital transducers made of a single magnetostrictive material, either Ni or TbFe2 , or based on exchange-biased (Co /IrMn ) multilayers. By controlling the ferromagnet magnetic properties, high-field sensors can be obtained with unipolar or bipolar responses. The issue of hysteretic response of the ferromagnetic material is especially addressed, and the control of the magnetic properties ensures the reversible behavior in the SAW response.

  15. Boundary layer receptivity phenomena in three-dimensional and high-speed boundary layers

    Science.gov (United States)

    Choudhari, Meelan; Streett, Craig L.

    1990-01-01

    The process by which the boundary layer internalizes the environmental disturbances in the form of instability waves is known as the boundary-layer receptivity. The paper discusses the importance of receptivity in transition research. The receptivity scenario for three-dimensional and high-speed boundary layers is examined. It is found that, while receptivity mechanisms present in the low-speed case are also operative in these complex flows, certain uniquely 'compressible' receptivity mechanisms may come into play as well. Both numerical, and where convenient, asymptotic procedures are utilized to develop quantitative predictions of the localized generation of a variety of instability types (Tollmien-Schlichting, inflectional, higher modes, crossflow vortices) in boundary layer flows relevant to the National Aero-Space Plane (NASP).

  16. An Exact Model-Based Method for Near-Field Sources Localization with Bistatic MIMO System

    OpenAIRE

    Singh, Parth Raj; Wang, Yide; Charg?, Pascal

    2017-01-01

    In this paper, we propose an exact model-based method for near-field sources localization with a bistatic multiple input, multiple output (MIMO) radar system, and compare it with an approximated model-based method. The aim of this paper is to propose an efficient way to use the exact model of the received signals of near-field sources in order to eliminate the systematic error introduced by the use of approximated model in most existing near-field sources localization techniques. The proposed...

  17. An improved route planning algorithm for unmanned aerial vehicle based on artificial potential field

    Directory of Open Access Journals (Sweden)

    Ran ZHEN

    2017-06-01

    Full Text Available In order to improve the precision and accuracy of artificial potential field, and avoid the situation of hovering on the end point and being caught in minimum value, a path planning algorithm based on artificial potential algorithm for unmanned aerial vehicle is presented. The traditional artificial potential field method is improved: chaos theory is used to improve artificial potential field calculation formula, which changes the potential field coefficients of each barrier and target point, resulting in the best screened out route. The simulation experimental analysis and result show that the optimized algorithm considers the influence of obstacles to the optimization process, ruling out the situation of hovering on the end point in unmanned aerial vehicle route planning, and through iterative method, the algorithm has the ability to adapt to different maps. The improved artificial potential field method is better than the traditional artificial potential field method in speed and precision aspects.

  18. Public magnetic field exposure based on internal current density for electric low voltage systems.

    Science.gov (United States)

    Keikko, Tommi; Seesvuori, Reino; Hyvönen, Martti; Valkealahti, Seppo

    2009-04-01

    A measurement concept utilizing a new magnetic field exposure metering system has been developed for indoor substations where voltage is transformed from a medium voltage of 10 or 20 kV to a low voltage of 400 V. The new metering system follows the guidelines published by the International Commission on Non-Ionizing Radiation Protection. It can be used to measure magnetic field values, total harmonic distortion of the magnetic field, magnetic field exposure ratios for public and workers, load current values, and total harmonic distortion of the load current. This paper demonstrates how exposure to non-sinusoidal magnetic fields and magnetic flux density exposure values can be compared directly with limit values for internal current densities in a human body. Further, we present how the magnetic field and magnetic field exposure behaves in the vicinity of magnetic field sources within the indoor substation and in the neighborhood. Measured magnetic fields around the substation components have been used to develop a measurement concept by which long-term measurements in the substations were performed. Long-term measurements revealed interesting and partly unexpected dependencies between the measured quantities, which have been further analyzed. The principle of this paper is to substitute a demanding exposure measurement with measurements of the basic quantities like the 50 Hz fundamental magnetic field component, which can be estimated based on the load currents for certain classes of substation lay-out.

  19. Composite Field Multiplier based on Look-Up Table for Elliptic Curve Cryptography Implementation

    Directory of Open Access Journals (Sweden)

    Marisa W. Paryasto

    2013-09-01

    Full Text Available Implementing a secure cryptosystem requires operations involving hundreds of bits. One of the most recommended algorithm is Elliptic Curve Cryptography (ECC. The complexity of elliptic curve algorithms and parameters with hundreds of bits requires specific design and implementation strategy. The design architecture must be customized according to security requirement, available resources and parameter choices. In this work we propose the use of composite field to implement finite field multiplication for ECC implementation. We use 299-bit keylength represented in GF((21323 instead of in GF(2299. Composite field multiplier can be implemented using different multiplier for ground-field and for extension field. In this paper, LUT is used for multiplication in the ground-field and classic multiplieris used for the extension field multiplication. A generic architecture for the multiplier is presented. Implementation is done with VHDL with the target device Altera DE2. The work in this paper uses the simplest algorithm to confirm the idea that by dividing field into composite, use different multiplier for base and extension field would give better trade-off for time and area. This work will be the beginning of our more advanced further research that implements composite-field using Mastrovito Hybrid, KOA and LUT.

  20. Taras Shevchenko’s Ballade “Why do you come to the grave?” and it’s Ideological and Aesthetic Reception by Jurij Fed’kovych

    Directory of Open Access Journals (Sweden)

    Lidija Kovalets

    2014-12-01

    Full Text Available In the article T. Shevchenko’s ballade “Why do you come to the grave?” (from cycle “In casemate” has been studied in the aspects of its ideological, thematic, imagery and artistic originality, and as an object of Fed’kovych’s purely individual productive reception, that took place in the mid 1860`s. Set of subjective and objective factors that contributed to it was found; creative and psychological conditions of that event, the previous writer’s achievements in the field of poetry, based on close relations with folklore and mainly German-speaking romantic literature were outlined. Specific Fed’kovych works, romantic too, were considered at the level of detection in it Shevchenko’s work stylization, motive studying, reminiscences ,figurative analogies etc. After all, each of that art dimensions remained sufficiently original, uniquely individual, that demonstrated their author’s high creative ability.

  1. Analysis of Magnetic Field Intensity and Induced Current under Live Working Based on Charge Simulation Method

    Directory of Open Access Journals (Sweden)

    Luo Yuanxiang

    2015-01-01

    Full Text Available To the problem that safety distance is insufficient for 500 kV substation live working, a magnetic field analysis method for overhead line bus is given based on the charge simulation method. In the method, charge is calculated firstly, and the space field intensity distribution calculation is completed by overlying charge. The space field intensity distribution rule is carried out based on the appropriate analysis, and space field intensity distribution rule of substation is obtained. Then according to the calculation formula of inducing current, the human body induction current under a substation busbar is simulated based on MATLAB. The simulation results have a certain guidance function for actual live working.

  2. Normal Threshold Size of Stimuli in Children Using a Game-Based Visual Field Test.

    Science.gov (United States)

    Wang, Yanfang; Ali, Zaria; Subramani, Siddharth; Biswas, Susmito; Fenerty, Cecilia; Henson, David B; Aslam, Tariq

    2017-06-01

    The aim of this study was to demonstrate and explore the ability of novel game-based perimetry to establish normal visual field thresholds in children. One hundred and eighteen children (aged 8.0 ± 2.8 years old) with no history of visual field loss or significant medical history were recruited. Each child had one eye tested using a game-based visual field test 'Caspar's Castle' at four retinal locations 12.7° (N = 118) from fixation. Thresholds were established repeatedly using up/down staircase algorithms with stimuli of varying diameter (luminance 20 cd/m2, duration 200 ms, background luminance 10 cd/m2). Relationships between threshold and age were determined along with measures of intra- and intersubject variability. The Game-based visual field test was able to establish threshold estimates in the full range of children tested. Threshold size reduced with increasing age in children. Intrasubject variability and intersubject variability were inversely related to age in children. Normal visual field thresholds were established for specific locations in children using a novel game-based visual field test. These could be used as a foundation for developing a game-based perimetry screening test for children.

  3. The Reception of Mao's 'Talks at the Yan'an Forum on Literature and Art' in English-language Scholarship

    National Research Council Canada - National Science Library

    Fu, Qilin

    2015-01-01

    In his article "The Reception of Mao's 'Talks at the Yan'an Forum on Literature and Art' in English-language Scholarship" Qilin Fu examines the three waves of the reception of Mao Zedong's 1942 text...

  4. Improvements to coal transport methods and associated site reception and handling facilities for the industrial user

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    A comprehensive coal handling system, installed at CRE for receiving, storing and supplying coal to a test boilerhouse, has shown itself generally reliable and environmentally attractive. The system comprises coal reception by means of a 22 tonne tipping hopper and storage within two silos, one of flat-bottomed concrete stave (250 tonnes) construction and the other of glassed steel (160 tonnes) construction with a hopper bottom. Transfer of coal between these components and boiler feed hoppers is provided by a dense-phase pneumatic conveying system. In addition to the tipping hopper two further reception systems, containerisation and a wide belt vehicle unloader, have been investigated. Facilities developed to receive, unload and tip standard 20 tonne capacity ISO containers have been installed at a customer trial site. Tests with a 200 mm diameter suction nozzle have demonstrated that coal conveying rates of up to 61 tonne/hr can be achieved. The consequence of long term storage of smalls coal has been investigated during a storage period of 12 months within the concrete stave silo at CRE. During this period, the carbon monoxide concentrations in the silo headspace underwent considerable daily variation. This was found to be dependent upon atmospheric temperature, pressure and windspeed. Based on the principles derived from a test unit, a hydraulic ash sluicing system has been installed to transport oversize ash extracted from the bed of a 9 MWt fluidised bed furnace at an industrial site. A low-cost, submerged, rubber belt wet ash extraction system has been installed on a modular boilerhouse which was on test at CRE. This unit has undergone long-term evaluation trials and has been operated successfully during a nine-month trial period. The unit, together with the modular boilerhouse, is to be moved to a customer site and a second unit has been placed on order. 13 refs., 48 figs., 5 tabs.

  5. A Comparison of Field-Based and Lab-Based Experiments to Evaluate User Experience of Personalised Mobile Devices

    Directory of Open Access Journals (Sweden)

    Xu Sun

    2013-01-01

    Full Text Available There is a growing debate in the literature regarding the tradeoffs between lab and field evaluation of mobile devices. This paper presents a comparison of field-based and lab-based experiments to evaluate user experience of personalised mobile devices at large sports events. A lab experiment is recommended when the testing focus is on the user interface and application-oriented usability related issues. However, the results suggest that a field experiment is more suitable for investigating a wider range of factors affecting the overall acceptability of the designed mobile service. Such factors include the system function and effects of actual usage contexts aspects. Where open and relaxed communication is important (e.g., where participant groups are naturally reticent to communicate, this is more readily promoted by the use of a field study.

  6. Margins of freedom: a field-theoretic approach to class-based health dispositions and practices.

    Science.gov (United States)

    Burnett, Patrick John; Veenstra, Gerry

    2017-09-01

    Pierre Bourdieu's theory of practice situates social practices in the relational interplay between experiential mental phenomena (habitus), resources (capitals) and objective social structures (fields). When applied to class-based practices in particular, the overarching field of power within which social classes are potentially made manifest is the primary field of interest. Applying relational statistical techniques to original survey data from Toronto and Vancouver, Canada, we investigated whether smoking, engaging in physical activity and consuming fruit and vegetables are dispersed in a three-dimensional field of power shaped by economic and cultural capitals and cultural dispositions and practices. We find that aesthetic dispositions and flexibility of developing and established dispositions are associated with positioning in the Canadian field of power and embedded in the logics of the health practices dispersed in the field. From this field-theoretic perspective, behavioural change requires the disruption of existing relations of harmony between the habitus of agents, the fields within which the practices are enacted and the capitals that inform and enforce the mores and regularities of the fields. The three-dimensional model can be explored at: http://relational-health.ca/margins-freedom. © 2017 Foundation for the Sociology of Health & Illness.

  7. Extracting flat-field images from scene-based image sequences using phase correlation

    Energy Technology Data Exchange (ETDEWEB)

    Caron, James N., E-mail: Caron@RSImd.com [Research Support Instruments, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States); Montes, Marcos J. [Naval Research Laboratory, Code 7231, 4555 Overlook Avenue, SW, Washington, DC 20375 (United States); Obermark, Jerome L. [Naval Research Laboratory, Code 8231, 4555 Overlook Avenue, SW, Washington, DC 20375 (United States)

    2016-06-15

    Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.

  8. Extracting flat-field images from scene-based image sequences using phase correlation.

    Science.gov (United States)

    Caron, James N; Montes, Marcos J; Obermark, Jerome L

    2016-06-01

    Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.

  9. Field-Based Teacher Education in Literacy: Preparing Teachers in Real Classroom Contexts

    Science.gov (United States)

    DeGraff, Tricia L.; Schmidt, Cynthia M.; Waddell, Jennifer H.

    2015-01-01

    For the past two decades, scholars have advocated for reforms in teacher education that emphasize relevant connections between theory and practice in university coursework and focus on clinical experiences. This paper is based on our experiences in designing and implementing an integrated literacy methods course in a field-based teacher education…

  10. Near field acoustic holography based on the equivalent source method and pressure-velocity transducers

    DEFF Research Database (Denmark)

    Zhang, Y.-B.; Chen, X.-Z.; Jacobsen, Finn

    2009-01-01

    The advantage of using the normal component of the particle velocity rather than the sound pressure in the hologram plane as the input of conventional spatial Fourier transform based near field acoustic holography (NAH) and also as the input of the statistically optimized variant of NAH has...... on particle velocity input data than when it is based on measurements of sound pressure data, and this is confirmed by a simulation study and by experimental results. A method that combines pressure- and particle velocity-based reconstructions in order to distinguish between contributions to the sound field...

  11. Simulation-based design of a strained graphene field effect transistor incorporating the pseudo magnetic field effect

    Energy Technology Data Exchange (ETDEWEB)

    Souma, Satofumi, E-mail: ssouma@harbor.kobe-u.ac.jp; Ueyama, Masayuki; Ogawa, Matsuto [Department of Electrical and Electronic Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501 (Japan)

    2014-05-26

    We present a numerical study on the performance of strained graphene-based field-effect transistors. A local strain less than 10% is applied over a central channel region of the graphene to induce the shift of the Dirac point in the channel region along the transverse momentum direction. The left and the right unstrained graphene regions are doped to be either n-type or p-type. By using the atomistic tight-binding model and a Green's function method, we predict that the gate voltage applied to the central strained graphene region can switch the drain current on and off with an on/off ratio of more than six orders of magnitude at room temperature. This is in spite of the absence of a bandgap in the strained channel region. Steeper subthreshold slopes below 60 mV/decade are also predicted at room temperature because of a mechanism similar to the band-to-band tunneling field-effect transistors.

  12. Glia delimit shape changes of sensory neuron receptive endings in C. elegans.

    Science.gov (United States)

    Procko, Carl; Lu, Yun; Shaham, Shai

    2011-04-01

    Neuronal receptive endings, such as dendritic spines and sensory protrusions, are structurally remodeled by experience. How receptive endings acquire their remodeled shapes is not well understood. In response to environmental stressors, the nematode Caenorhabditis elegans enters a diapause state, termed dauer, which is accompanied by remodeling of sensory neuron receptive endings. Here, we demonstrate that sensory receptive endings of the AWC neurons in dauers remodel in the confines of a compartment defined by the amphid sheath (AMsh) glial cell that envelops these endings. AMsh glia remodel concomitantly with and independently of AWC receptive endings to delimit AWC receptive ending growth. Remodeling of AMsh glia requires the OTD/OTX transcription factor TTX-1, the fusogen AFF-1 and probably the vascular endothelial growth factor (VEGFR)-related protein VER-1, all acting within the glial cell. ver-1 expression requires direct binding of TTX-1 to ver-1 regulatory sequences, and is induced in dauers and at high temperatures. Our results demonstrate that stimulus-induced changes in glial compartment size provide spatial constraints on neuronal receptive ending growth.

  13. Receptive vocabulary and early literacy skills in emergent bilingual Northern Sotho-English children

    Directory of Open Access Journals (Sweden)

    Carien Wilsenach

    2015-04-01

    Full Text Available This study explored receptive vocabulary size and early literacy skills (namely: letter naming, knowledge of phoneme-grapheme correspondences and early writing in emergent bilingual Northern Sotho-English children. Two groups of Grade 1 learners were tested in both English and in Northern Sotho. Group 1 (N = 49 received their formal schooling in English, whilst group 2 (N = 50 received their formal schooling in Northern Sotho. Receptive vocabulary was tested using the Peabody Picture Vocabulary Test. Letter knowledge was assessed by asking learners to name letter cards, whilst knowledge of phoneme-grapheme correspondences was tested by asking children to match letter cards with spoken sounds. Early writing was assessed by asking children to write their names. Statistical analyses indicated that both English and Northern Sotho receptive vocabulary knowledge had a significant effect on early literacy skills, whilst no main effect was found for the language of instruction. Group 1 performed significantly better than Group 2 in English receptive vocabulary, in knowledge of phonemegrapheme correspondences and in early writing, but no group differences were found for Northern Sotho receptive vocabulary or for letter knowledge. English receptive vocabulary significantly predicted the outcome of all of the early literacy skills, whilst Northern Sotho receptive vocabulary significantly predicted phoneme-grapheme correspondences and early writing.

  14. Three-dimensional reconstruction of sound fields based on the acousto-optic effect

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Torras Rosell, Antoni

    2013-01-01

    The acousto-optic effect can be used to measure the pressure fluctuations in air created by acoustic disturbances (the propagation of light is affected by changes in the medium due to the presence of sound waves). This makes it possible to measure an arbitrary sound field using acousto...... of sound pressure fields from acousto-optic measurements in the audible frequency range, based on Fourier transforms and elementary wave expansion methods. The present study examines the complete reconstruction of the sound field from acousto-optic measurements, recovering all acoustic quantities......-optic tomography via scanning the field with a laser Doppler vibrometer. Consequently, the spatial characteristics of the sound field are captured in the measurement, implicitly bearing the potential for a full holographic reconstruction in a three-dimensional space. Recent studies have examined the reconstruction...

  15. Study on the Electronic Magnetic Field Oriented Control Based on D-axis Current

    Directory of Open Access Journals (Sweden)

    Hongyu Feng

    2014-07-01

    Full Text Available In order to improve the magnetic field orientation accuracy and system performance, the electronic field oriented control has been a hot research field of the induction motor speed control. Although the vector control of AC machines has many excellent properties, the researchers have been attempting to simplify the calculating steps and the structure of the control system to improve the accuracy of filed-oriented and the performance of AC machine drives. Based on the analysis of the conventional induction motor magnetic field oriented control, this paper puts forward a novel method of stator magnetic field orientation control. By analytical methods, the given current of d-axis can be calculated directly, and the stator flux can be controlled precisely. This method has a fast flux and torque response, and the control performance is unaffected by the rotor parameters.

  16. Magnetoluminescence of light-emitting field-effect transistors based on alpha sexithiophene

    Science.gov (United States)

    Pham, Song-Toan; Tada, Hirokazu

    2014-03-01

    We demonstrated the effect of a magnetic field on the luminous intensity and electric current of light-emitting field-effect transistors (LEFETs) based on alpha sexithiophene (α-6T). Sublimate-grade α-6T was thermally deposited on an n+-Si/300 nm-SiO2 substrate with patterned asymmetric gold-aluminum electrodes to fabricate a bottom-contact LEFET. We observed an increase in luminous intensity of approximately 1.3% under a magnetic field of 100 mT. A possible explanation for this is that the magnetic field increased the probability of singlet formation at the α-6T/Al interface. While the magneto-electroluminescence (MEL) was reported to be derived from the magneto-conductance (MC) in ordinary light emitting diodes, the MEL in LEFET was independent with MC. This indicates that the luminous efficiency can be improved by optimizing the magnetic field effect.

  17. Creating analytically divergence-free velocity fields from grid-based data

    Science.gov (United States)

    Ravu, Bharath; Rudman, Murray; Metcalfe, Guy; Lester, Daniel R.; Khakhar, Devang V.

    2016-10-01

    We present a method, based on B-splines, to calculate a C2 continuous analytic vector potential from discrete 3D velocity data on a regular grid. A continuous analytically divergence-free velocity field can then be obtained from the curl of the potential. This field can be used to robustly and accurately integrate particle trajectories in incompressible flow fields. Based on the method of Finn and Chacon (2005) [10] this new method ensures that the analytic velocity field matches the grid values almost everywhere, with errors that are two to four orders of magnitude lower than those of existing methods. We demonstrate its application to three different problems (each in a different coordinate system) and provide details of the specifics required in each case. We show how the additional accuracy of the method results in qualitatively and quantitatively superior trajectories that results in more accurate identification of Lagrangian coherent structures.

  18. Impaired receptivity and decidualization in DHEA-induced PCOS mice.

    Science.gov (United States)

    Li, Shu-Yun; Song, Zhuo; Song, Min-Jie; Qin, Jia-Wen; Zhao, Meng-Long; Yang, Zeng-Ming

    2016-12-07

    Polycystic ovary syndrome (PCOS), a complex endocrine disorder, is a leading cause of female infertility. An obvious reason for infertility in PCOS women is anovulation. However, success rate with high quality embryos selected by assisted reproduction techniques in PCOS patients still remain low with a high rate of early clinical pregnancy loss, suggesting a problem in uterine receptivity. Using a dehydroepiandrosterone-induced mouse model of PCOS, some potential causes of decreased fertility in PCOS patients were explored. In our study, ovulation problem also causes sterility in PCOS mice. After blastocysts from normal mice are transferred into uterine lumen of pseudopregnant PCOS mice, the rate of embryo implantation was reduced. In PCOS mouse uteri, the implantation-related genes are also dysregulated. Additionally, artificial decidualization is severely impaired in PCOS mice. The serum estrogen level is significantly higher in PCOS mice than vehicle control. The high level of estrogen and potentially impaired LIF-STAT3 pathway may lead to embryo implantation failure in PCOS mice. Although there are many studies about effects of PCOS on endometrium, both embryo transfer and artificial decidualization are applied to exclude the effects from ovulation and embryos in our study.

  19. Genetic influences on receptive joint attention in chimpanzees (Pan troglodytes).

    Science.gov (United States)

    Hopkins, William D; Keebaugh, Alaine C; Reamer, Lisa A; Schaeffer, Jennifer; Schapiro, Steven J; Young, Larry J

    2014-01-20

    Despite their genetic similarity to humans, our understanding of the role of genes on cognitive traits in chimpanzees remains virtually unexplored. Here, we examined the relationship between genetic variation in the arginine vasopressin V1a receptor gene (AVPR1A) and social cognition in chimpanzees. Studies have shown that chimpanzees are polymorphic for a deletion in a sequence in the 5' flanking region of the AVPR1A, DupB, which contains the variable RS3 repetitive element, which has been associated with variation in social behavior in humans. Results revealed that performance on the social cognition task was significantly heritable. Furthermore, males with one DupB(+) allele performed significantly better and were more responsive to socio-communicative cues than males homozygous for the DupB- deletion. Performance on a non-social cognition task was not associated with the AVPR1A genotype. The collective findings show that AVPR1A polymorphisms are associated with individual differences in performance on a receptive joint attention task in chimpanzees.

  20. Select interneuron clusters determine female sexual receptivity in Drosophila.

    Science.gov (United States)

    Sakurai, Akira; Koganezawa, Masayuki; Yasunaga, Kei-ichiro; Emoto, Kazuo; Yamamoto, Daisuke

    2013-01-01

    Female Drosophila with the spinster mutation repel courting males and rarely mate. Here we show that the non-copulating phenotype can be recapitulated by the elimination of spinster functions from either spin-A or spin-D neuronal clusters, in the otherwise wild-type (spinster heterozygous) female brain. Spin-D corresponds to the olfactory projection neurons with dendrites in the antennal lobe VA1v glomerulus that is fruitless-positive, sexually dimorphic and responsive to fly odour. Spin-A is a novel local neuron cluster in the suboesophageal ganglion, which is known to process contact chemical pheromone information and copulation-related signals. A slight reduction in spinster expression to a level with a minimal effect is sufficient to shut off female sexual receptivity if the dominant-negative mechanistic target of rapamycin is simultaneously expressed, although the latter manipulation alone has only a marginal effect. We propose that spin-mediated mechanistic target of rapamycin signal transduction in these neurons is essential for females to accept the courting male.

  1. Effect of atom- and group-based truncations on biomolecules simulated with reaction-field electrostatics

    Science.gov (United States)

    Ni, Boris

    2011-01-01

    The performance of the reaction-field method of electrostatics is tested in molecular dynamics simulations of protein human interleukin-4 and a short DNA fragment in explicit solvent. Two truncation schemes are considered: one based on the position of atomic charges in water molecules and the other on the position of groups of charges. The group-based truncation leads to the melting of the DNA double helix. In contrast, the atom-based truncation maintains the helical structure intact. Similarly for the protein, the group-based truncation leads to an unfolding at pH 2 while the atom-based truncation produces stable trajectories at low and normal pH, in agreement with experiment. Artificial repulsion between charged residues associated with the group-based truncation is identified as the microscopic reason behind unfolding of the protein. Implications of different truncation schemes in reaction-field simulations of biomolecules are discussed. PMID:21311933

  2. A Platform to Optimize the Field Emission Properties of Carbon Nanotube Based Fibers (Postprint)

    Science.gov (United States)

    2016-08-25

    AFRL-RX-WP-JA-2017-0351 A PLATFORM TO OPTIMIZE THE FIELD EMISSION PROPERTIES OF CARBON - NANOTUBE -BASED FIBERS (POSTPRINT) Steven B...28 April 2017 Interim 6 May 2010 – 20 August 2016 4. TITLE AND SUBTITLE A PLATFORM TO OPTIMIZE THE FIELD EMISSION PROPERTIES OF CARBON - NANOTUBE ...ieeexplore.ieee.org DOI: 10.1109/IVNC.2016.7551456 14. ABSTRACT (Maximum 200 words) Building on recent efforts [1-4] to characterize carbon nanotube

  3. Asphalt Pavement Pothole Detection and Segmentation Based on Wavelet Energy Field

    OpenAIRE

    Penghui Wang; Yongbiao Hu; Yong Dai; Mingrui Tian

    2017-01-01

    Potholes are one type of pavement surface distresses whose assessment is essential for developing road network maintenance strategies. Existing methods for automatic pothole detection either rely on expensive and high-maintenance equipment or could not segment the pothole accurately. In this paper, an asphalt pavement pothole detection and segmentation method based on energy field is put forward. The proposed method mainly includes two processes. Firstly, the wavelet energy field of the pavem...

  4. Efficient Compression of Far Field Matrices in Multipole Algorithms based on Spherical Harmonics and Radiating Modes

    Directory of Open Access Journals (Sweden)

    A. Schroeder

    2012-09-01

    Full Text Available This paper proposes a compression of far field matrices in the fast multipole method and its multilevel extension for electromagnetic problems. The compression is based on a spherical harmonic representation of radiation patterns in conjunction with a radiating mode expression of the surface current. The method is applied to study near field effects and the far field of an antenna placed on a ship surface. Furthermore, the electromagnetic scattering of an electrically large plate is investigated. It is demonstrated, that the proposed technique leads to a significant memory saving, making multipole algorithms even more efficient without compromising the accuracy.

  5. Directional Solidification Microstructure of a Ni-Based Superalloy: Influence of a Weak Transverse Magnetic Field

    OpenAIRE

    Li, Xu; Wang, Jun; Zhang, Jiao; Han, Yanfeng; Li, Xi

    2015-01-01

    A Ni-based superalloy CMSX-6 was directionally solidified at various drawing speeds (5–20 μm·s−1) and diameters (4 mm, 12 mm) under a 0.5 T weak transverse magnetic field. The results show that the application of a weak transverse magnetic field significantly modified the solidification microstructure. It was found that if the drawing speed was lower than 10 μm·s−1, the magnetic field caused extensive macro-segregation in the mushy zone, and a change in the mushy zone length. The magnetic fie...

  6. MCP-based detector in the Magnetic Field: Some results and perspectives

    CERN Document Server

    Patarakin, O O; CERN. Geneva; Kartamushev, A A; Tikhonov, V N

    1997-01-01

    This paper presents the experimental results of the MCP-based detector timing resolution studying. The timing resolution of shevron-type MCP-detector was obtained =82±2 ps as without magnetic field as with longitudinal magnetic field at 1.5 kG. It was shown that a deterioration of a timing resolution in this field is smaller than 20 ps. The timing resolution =31±2 ps had been obtained for thin (10%) amplitude spectrum

  7. Near field thermal memory based on radiative phase bistability of VO2

    Science.gov (United States)

    Dyakov, S. A.; Dai, J.; Yan, M.; Qiu, M.

    2015-08-01

    We report the concept of a near-field memory device based on the radiative bistability effect in the system of two closely separated parallel plates of SiO2 and VO2 which exchange heat by thermal radiation in vacuum. We demonstrate that the VO2 plate, having metal-insulator transition at 340 K, has two thermodynamical steady-states. One can switch between the states using an external laser impulse. We show that due to near-field photon tunneling between the plates, the switching time is found to be only 5 ms which is several orders lower than in case of far field.

  8. Integral imaging based light field display with enhanced viewing resolution using holographic diffuser

    Science.gov (United States)

    Yan, Zhiqiang; Yan, Xingpeng; Jiang, Xiaoyu; Gao, Hui; Wen, Jun

    2017-11-01

    An integral imaging based light field display method is proposed by use of holographic diffuser, and enhanced viewing resolution is gained over conventional integral imaging systems. The holographic diffuser is fabricated with controlled diffusion characteristics, which interpolates the discrete light field of the reconstructed points to approximate the original light field. The viewing resolution can thus be improved and independent of the limitation imposed by Nyquist sampling frequency. An integral imaging system with low Nyquist sampling frequency is constructed, and reconstructed scenes of high viewing resolution using holographic diffuser are demonstrated, verifying the feasibility of the method.

  9. The Foucault-Habermas Debate: the Reflexive and Receptive Aspects of Critique

    DEFF Research Database (Denmark)

    Hansen, Ejvind

    2005-01-01

    In this paper I discuss the relationship between two different approaches to critical theory – the reflective and the receptive approaches. I show how it can be fruitful to discuss the relationship between Habermas and Foucault through this distinction. My point is that whereas Habermas focusses...... on critique as a reflexive activity, Foucault mainly focusses on the receptive conditions for critique to be possible. I argue further that Foucault focusses on the receptive aspects of critique, the quest for universality is not as pressing as it is in Habermas’ approach, because problematizing critique can...

  10. Problem Internet Overuse Behaviors in College Students: Readiness-to-Change and Receptivity to Treatment.

    Science.gov (United States)

    O'Brien, Jennifer E; Li, Wen; Snyder, Susan M; Howard, Matthew O

    2016-01-01

    This mixed methods study explores college students' readiness-to-change and receptivity to treatment for problem Internet overuse behaviors. Focus groups were conducted with 27 college students who self-identified as Internet over-users, and had experienced biopsychosocial problems related to Internet overuse. Participants completed standardized questionnaires assessing their Internet use and sociodemographic forms. Focus groups explored readiness to change problem Internet overuse behaviors and receptivity to treatment. Similar to college students with other addictive behaviors, students with problem Internet overuse fall along a continuum vis-à-vis readiness-to-change their behaviors. Over half of the participants were receptive to treatment for their problem Internet overuse behaviors.

  11. Light distribution analysis of optical fibre probe-based near-field optical tweezers using FDTD

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B H; Yang, L J; Wang, Y [School of Mechanical and Electrical Engineering, Harbin Institute of Technology, Heilongjiang, Harbin, 150001 (China)], E-mail: richelaw@163.com

    2009-09-01

    Optical fibre probe-based near-field optical tweezers overcomes the diffraction limit of conventional optical tweezers, utilizing strong mechanical forces and torque associated with highly enhanced electric fields to trap and manipulate nano-scale particles. Near-field evanescent wave generated at optical fibre probe decays rapidly with the distance that results a significant reduced trapping volume, thus it is necessary to analyze the near-field distribution of optical fibre probe. The finite difference time domain (FDTD) method is applied to characterize the near-field distribution of optical fibre probe. In terms of the distribution patterns, depolarization and polarization, the near-field distributions in longitudinal sections and cross-sections of tapered metal-coated optical fibre probe are calculated. The calculation results reveal that the incident polarized wave becomes depolarized after exiting from the nano-scale aperture of probe. The near-field distribution of the probe is unsymmetrical, and the near-field distribution in the cross-section vertical to the incident polarized wave is different from that in the cross-section parallel to the incident polarized wave. Moreover, the polarization of incident wave has a great impact on the light intensity distribution.

  12. An Exact Model-Based Method for Near-Field Sources Localization with Bistatic MIMO System.

    Science.gov (United States)

    Singh, Parth Raj; Wang, Yide; Chargé, Pascal

    2017-03-30

    In this paper, we propose an exact model-based method for near-field sources localization with a bistatic multiple input, multiple output (MIMO) radar system, and compare it with an approximated model-based method. The aim of this paper is to propose an efficient way to use the exact model of the received signals of near-field sources in order to eliminate the systematic error introduced by the use of approximated model in most existing near-field sources localization techniques. The proposed method uses parallel factor (PARAFAC) decomposition to deal with the exact model. Thanks to the exact model, the proposed method has better precision and resolution than the compared approximated model-based method. The simulation results show the performance of the proposed method.

  13. Field site leaching from recycled concrete aggregates applied as sub-base material in road construction.

    Science.gov (United States)

    Engelsen, Christian J; Wibetoe, Grethe; van der Sloot, Hans A; Lund, Walter; Petkovic, Gordana

    2012-06-15

    The release of major and trace elements from recycled concrete aggregates used in an asphalt covered road sub-base has been monitored for more than 4 years. A similar test field without an asphalt cover, directly exposed to air and rain, and an asphalt covered reference field with natural aggregates in the sub-base were also included in the study. It was found that the pH of the infiltration water from the road sub-base with asphalt covered concrete aggregates decreased from 12.6 to below pH 10 after 2.5 years of exposure, whereas this pH was reached within only one year for the uncovered field. Vertical temperature profiles established for the sub-base, could explain the measured infiltration during parts of the winter season. When the release of major and trace elements as function of field pH was compared with pH dependent release data measured in the laboratory, some similar pH trends were found. The field concentrations of Cd, Ni, Pb and Zn were found to be low throughout the monitoring period. During two of the winter seasons, a concentration increase of Cr and Mo was observed, possibly due to the use of de-icing salt. The concentrations of the trace constituents did not exceed Norwegian acceptance criteria for ground water and surface water Class II. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Polylactic Acid Based Nanocomposites: Promising Safe and Biodegradable Materials in Biomedical Field

    Directory of Open Access Journals (Sweden)

    Lili Sha

    2016-01-01

    Full Text Available Polylactic acid (PLA is widely used in biological areas due to its excellent compatibility, bioabsorbability, and degradation behavior in human bodies. Pure polylactic acid has difficulty in meeting all the requirements that specific field may demand. Therefore, PLA based nanocomposites are extensively investigated over the past few decades. PLA based nanocomposites include PLA based copolymers in nanometer size and nanocomposites with PLA or PLA copolymers as matrix and nanofillers as annexing agent. The small scale effect and surface effect of nanomaterials help improve the properties of PLA and make PLA based nanocomposites more popular compared with pure PLA materials. This review mainly introduces different kinds of PLA based nanocomposites in recent researches that have great potential to be used in biomedical fields including bone substitute and repair, tissue engineering, and drug delivery system.

  15. Proposed Robust Entanglement-Based Magnetic Field Sensor Beyond the Standard Quantum Limit.

    Science.gov (United States)

    Tanaka, Tohru; Knott, Paul; Matsuzaki, Yuichiro; Dooley, Shane; Yamaguchi, Hiroshi; Munro, William J; Saito, Shiro

    2015-10-23

    Recently, there have been significant developments in entanglement-based quantum metrology. However, entanglement is fragile against experimental imperfections, and quantum sensing to beat the standard quantum limit in scaling has not yet been achieved in realistic systems. Here, we show that it is possible to overcome such restrictions so that one can sense a magnetic field with an accuracy beyond the standard quantum limit even under the effect of decoherence, by using a realistic entangled state that can be easily created even with current technology. Our scheme could pave the way for the realizations of practical entanglement-based magnetic field sensors.

  16. Field trial of 160 Gbit/s DWDM-based optical packet switching and transmission.

    Science.gov (United States)

    Furukawa, Hideaki; Wada, Naoya; Awaji, Yoshinari; Miyazaki, Tetsuya; Kong, Eddie; Chan, Peter; Man, Ray; Cincotti, Gabriella; Kitayama, Ken-ichi

    2008-07-21

    We demonstrated, for the first time, a field trial of 160 (16 lambda x 10) Gbit/s, fine granularity, DWDM-based optical packet switching and transmission by newly-developed burst-mode EDFAs and an optical packet switch prototype with multiple all-optical label processors. We achieved 64 km field transmission and switching of 160 (16 lambda x 10) Gbit/s DWDM-based optical packets encapsulating almost 10 Gbit/s IP packets with error-free operation (IP-packet-loss-rate <10(-6) and bit-error-rate <10(-9)).

  17. Optimization of light field display-camera configuration based on display properties in spectral domain.

    Science.gov (United States)

    Bregović, Robert; Kovács, Péter Tamás; Gotchev, Atanas

    2016-02-08

    The visualization capability of a light field display is uniquely determined by its angular and spatial resolution referred to as display passband. In this paper we use a multidimensional sampling model for describing the display-camera channel. Based on the model, for a given display passband, we propose a methodology for determining the optimal distribution of ray generators in a projection-based light field display. We also discuss the required camera setup that can provide data with the necessary amount of details for such display that maximizes the visual quality and minimizes the amount of data.

  18. HIGH-SCALE THEMATIC MAPPING BASED ON FIELD SURVEY DATA (CASE OF VESLOVSKY PENINSULA, KUNASHIR ISLAND

    Directory of Open Access Journals (Sweden)

    V. I. Gavrilova

    2015-01-01

    Full Text Available Currently, high-scale field surveys-based thematic mapping is not very widespread, though it provides detailed and accurate information about the study area, presented in representative cartographic form. In this paper, authors present the soil map and landscape map of Veslovsky peninsula (Kunashir island, Kuril islands based on wide field surveys led in summer of 2014. Veslovsky peninsula is located in the buffer zone of the Kuril nature reserve. The maps provide detailed information on the soil cover and the landscape differentiation of the study area.

  19. Divine Love: The Reception of Leda and the Swan Myth in Works by Jewish and Arab Israeli Artists - Contexts and Meanings

    Directory of Open Access Journals (Sweden)

    Nava Sevilla Sadeh

    2014-09-01

    Full Text Available The motif of the abduction of a woman is one of the most frequent in Ancient Greek and Roman art. Abductions in mythology are generally portrayed as carried out by a god disguised as a human or an animal, such as Zeus who, in the form of a bull, golden rain or a swan, seduces a beautiful young maiden. These myths have been interpreted from different viewpoints, such as gender, social, political and philosophical. One of the most frequent myths of abduction is that of Leda and the Swan, which appears in both Greek and Roman painting and sculpture. This theme has found many echoes in contemporary Israeli art, and constitutes the case study for this discussion, which belongs to the field of Classical Reception studies. The interpretations of this myth are diverse, ranging from a socio-gender context, to post-colonialism and its relevance to the local situation; to subversives, concerning tradition versus contemporary culture; to emotionality and romantic suffering; and to love as phantasmagoria. These varied interpretations will be examined in the following analysis in light of both ancient concepts and contemporary outlooks, based on literary and philosophical sources.

  20. Electric field strength determination in filamentary DBDs by CARS-based four-wave mixing

    Science.gov (United States)

    Boehm, Patrick; Kettlitz, Manfred; Brandenburg, Ronny; Hoeft, Hans; Czarnetzki, Uwe

    2016-09-01

    The electric field strength is a basic parameter of non-thermal plasmas. Therefore, a profound knowledge of the electric field distribution is crucial. In this contribution a four wave mixing technique based on Coherent Anti-Stokes Raman spectroscopy (CARS) is used to measure electric field strengths in filamentary dielectric barrier discharges (DBDs). The discharges are operated with a pulsed voltage in nitrogen at atmospheric pressure. Small amounts hydrogen (10 vol%) are admixed as tracer gas to evaluate the electric field strength in the 1 mm discharge gap. Absolute values of the electric field strength are determined by calibration of the CARS setup with high voltage amplitudes below the ignition threshold of the arrangement. Alteration of the electric field strength has been observed during the internal polarity reversal and the breakdown process. In this case the major advantage over emission based methods is that this technique can be used independently from emission, e.g. in the pre-phase and in between two consecutive, opposite discharge pulses where no emission occurs at all. This work was supported by the Deutsche Forschungsgemeinschaft, Forschergruppe FOR 1123 and Sonderforschungsbereich TRR 24 ``Fundamentals of complex plasmas''.

  1. High Accuracy Passive Magnetic Field-Based Localization for Feedback Control Using Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Shaohui Foong

    2016-08-01

    Full Text Available In this paper, a novel magnetic field-based sensing system employing statistically optimized concurrent multiple sensor outputs for precise field-position association and localization is presented. This method capitalizes on the independence between simultaneous spatial field measurements at multiple locations to induce unique correspondences between field and position. This single-source-multi-sensor configuration is able to achieve accurate and precise localization and tracking of translational motion without contact over large travel distances for feedback control. Principal component analysis (PCA is used as a pseudo-linear filter to optimally reduce the dimensions of the multi-sensor output space for computationally efficient field-position mapping with artificial neural networks (ANNs. Numerical simulations are employed to investigate the effects of geometric parameters and Gaussian noise corruption on PCA assisted ANN mapping performance. Using a 9-sensor network, the sensing accuracy and closed-loop tracking performance of the proposed optimal field-based sensing system is experimentally evaluated on a linear actuator with a significantly more expensive optical encoder as a comparison.

  2. High Accuracy Passive Magnetic Field-Based Localization for Feedback Control Using Principal Component Analysis.

    Science.gov (United States)

    Foong, Shaohui; Sun, Zhenglong

    2016-08-12

    In this paper, a novel magnetic field-based sensing system employing statistically optimized concurrent multiple sensor outputs for precise field-position association and localization is presented. This method capitalizes on the independence between simultaneous spatial field measurements at multiple locations to induce unique correspondences between field and position. This single-source-multi-sensor configuration is able to achieve accurate and precise localization and tracking of translational motion without contact over large travel distances for feedback control. Principal component analysis (PCA) is used as a pseudo-linear filter to optimally reduce the dimensions of the multi-sensor output space for computationally efficient field-position mapping with artificial neural networks (ANNs). Numerical simulations are employed to investigate the effects of geometric parameters and Gaussian noise corruption on PCA assisted ANN mapping performance. Using a 9-sensor network, the sensing accuracy and closed-loop tracking performance of the proposed optimal field-based sensing system is experimentally evaluated on a linear actuator with a significantly more expensive optical encoder as a comparison.

  3. Radio frequency electromagnetic field compliance assessment of multi-band and MIMO equipped radio base stations.

    Science.gov (United States)

    Thors, Björn; Thielens, Arno; Fridén, Jonas; Colombi, Davide; Törnevik, Christer; Vermeeren, Günter; Martens, Luc; Joseph, Wout

    2014-05-01

    In this paper, different methods for practical numerical radio frequency exposure compliance assessments of radio base station products were investigated. Both multi-band base station antennas and antennas designed for multiple input multiple output (MIMO) transmission schemes were considered. For the multi-band case, various standardized assessment methods were evaluated in terms of resulting compliance distance with respect to the reference levels and basic restrictions of the International Commission on Non-Ionizing Radiation Protection. Both single frequency and multiple frequency (cumulative) compliance distances were determined using numerical simulations for a mobile communication base station antenna transmitting in four frequency bands between 800 and 2600 MHz. The assessments were conducted in terms of root-mean-squared electromagnetic fields, whole-body averaged specific absorption rate (SAR) and peak 10 g averaged SAR. In general, assessments based on peak field strengths were found to be less computationally intensive, but lead to larger compliance distances than spatial averaging of electromagnetic fields used in combination with localized SAR assessments. For adult exposure, the results indicated that even shorter compliance distances were obtained by using assessments based on localized and whole-body SAR. Numerical simulations, using base station products employing MIMO transmission schemes, were performed as well and were in agreement with reference measurements. The applicability of various field combination methods for correlated exposure was investigated, and best estimate methods were proposed. Our results showed that field combining methods generally considered as conservative could be used to efficiently assess compliance boundary dimensions of single- and dual-polarized multicolumn base station antennas with only minor increases in compliance distances. © 2014 Wiley Periodicals, Inc.

  4. Layout Optimization of Sensor-based Reconstruction of Explosion Overpressure Field Based on the Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Miaomiao Bai

    2014-11-01

    Full Text Available In underwater blasting experiment, the layout of the sensor has always been highly concerned. From the perspective of reconstruction with explosion overpressure field, the paper presents four indicators, which can obtain the optimal sensor layout scheme and guide sensor layout in practical experiment, combining with the genetic algorithm with global search. Then, a multi-scale model in every subregion of underwater blasting field was established to be used simulation experiments. By Matlab, the variation of these four indicators with different sensor layout, and reconstruction accuracy are analyzed and discussed. Finally, a conclusion has been raised through the analysis and comparison of simulation results, that the program can get a better sensor layout. It requires fewer number of sensors to be able to get good results with high accuracy. In the actual test explosions, we can refer to this scheme laid sensors.

  5. Receptive vocabulary in boys with autism spectrum disorder: cross-sectional developmental trajectories.

    Science.gov (United States)

    Kover, Sara T; McDuffie, Andrea S; Hagerman, Randi J; Abbeduto, Leonard

    2013-11-01

    In light of evidence that receptive language may be a relative weakness for individuals with autism spectrum disorder (ASD), this study characterized receptive vocabulary profiles in boys with ASD using cross-sectional developmental trajectories relative to age, nonverbal cognition, and expressive vocabulary. Participants were 49 boys with ASD (4-11 years) and 80 typically developing boys (2-11 years). Receptive vocabulary, assessed with the Peabody Picture Vocabulary Test, was a weakness for boys with ASD relative to age and nonverbal cognition. Relative to expressive vocabulary, assessed with the Expressive Vocabulary Test, receptive vocabulary increased at a lower rate for boys with ASD. Vocabulary trajectories in ASD are distinguished from typical development; however, nonverbal cognition largely accounts for the patterns observed.

  6. Exploring racial politics, personal history and critical reception: Clarence Brown's Intruder in the dust (1949)

    National Research Council Canada - National Science Library

    Young, Gwenda

    2013-01-01

    Discusses the complexities of director Clarence Brown's 1949 film "Intruder in the dust" concerning racial issues, the personal and social elements that contributed to its inception, and its reception...

  7. Receptive Vocabulary in Boys with Autism Spectrum Disorder: Cross-Sectional Developmental Trajectories

    Science.gov (United States)

    McDuffie, Andrea S.; Hagerman, Randi J.; Abbeduto, Leonard

    2013-01-01

    In light of evidence that receptive language may be a relative weakness for individuals with autism spectrum disorder (ASD), this study characterized receptive vocabulary profiles in boys with ASD using cross-sectional developmental trajectories relative to age, nonverbal cognition, and expressive vocabulary. Participants were 49 boys with ASD (4–11 years) and 80 typically developing boys (2–11 years). Receptive vocabulary, assessed with the Peabody Picture Vocabulary Test, was a weakness for boys with ASD relative to age and nonverbal cognition. Relative to expressive vocabulary, assessed with the Expressive Vocabulary Test, receptive vocabulary increased at a lower rate for boys with ASD. Vocabulary trajectories in ASD are distinguished from typical development; however, nonverbal cognition largely accounts for the patterns observed. PMID:23588510

  8. Cultural conditions and reception of psychoanalysis in Córdoba, Argentina (1915-1942

    Directory of Open Access Journals (Sweden)

    Fernando José Ferrari

    2014-05-01

    Full Text Available In the present review we aim to outline the main conditions for the reception of Freud’s theory in Cordoba, Argentine. We will try to display the distinctive points that this process had and establish the differences occurred with the reception of Freud in the city of Buenos Aires. These cultural characteristics that frame the reception of the ideas of the Viennese physician are part of a fundamental and constitutive tension in Argen0tinian’s history. That is why our work introduces, as an interpretative axis, the interior-harbor dichotomy that accounts for such political and cultural tensions. We will expose the principal axes of the reception in Cordoba: 1 rejection and discussion of positivism 2 the existence of a traditional culture and conservative religious thought and 3 influence of Hispanic culture, and especially the Spanish vitalist philosophy implemented by Ortega y Gasset and Eugenio D’Ors.

  9. Theoretical and experimental research on diversity reception technology in NLOS UV communication system.

    Science.gov (United States)

    Han, Dahai; Liu, Yile; Zhang, Kai; Luo, Pengfei; Zhang, Min

    2012-07-02

    Diversity reception technology is introduced into ultraviolet communication area in this article with theory analysis and practical experiment. The idea of diversity reception was known as a critical effective method in wireless communication area that improves the Gain significantly especially for the multi-scattering channel. A theoretical modeling and simulation method are proposed to depict the principle and feasibility of diversity reception adopted in UV communication. Besides, an experimental test-bed using ultraviolet LED and dual receiver of photomultiplier tube is setup to characterize the effects of diversity receiving in non-line-of-sight (NLOS) ultraviolet communication system. The experiment results are compared with the theoretical ones to verify the accuracy of theoretical modeling and the effect of diversity reception. Equal gain combining (EGC) method was adopted as the diversity mechanism in this paper. The research results of theory and experiment provide insight into the channel characteristics and achievable capabilities of ultraviolet communication system with diversity receiving method.

  10. Tactual Vocoders in a Multisensory Program Training Speech Production and Reception.

    Science.gov (United States)

    Oller, D. Kimbrough; And Others

    1986-01-01

    Results of a program using vibrotactile and electrocutaneous vocoder in speech reception and production training with 13 profoundly hearing impaired Ss (3-6 years old) showed progress in speech communication not seen prior to training with tactual vocoders. (CL)

  11. A Magnetic Field Sensor Based on a Magnetic Fluid-Filled FP-FBG Structure

    Directory of Open Access Journals (Sweden)

    Ji Xia

    2016-04-01

    Full Text Available Based on the characteristic magnetic-controlled refractive index property, in this paper, a magnetic fluid is used as a sensitive medium to detect the magnetic field in the fiber optic Fabry-Perot (FP cavity. The temperature compensation in fiber Fabry-Perot magnetic sensor is demonstrated and achieved. The refractive index of the magnetic fluid varies with the applied magnetic field and external temperature, and a cross-sensitivity effect of the temperature and magnetic field occurs in the Fabry-Perot magnetic sensor and the accuracy of magnetic field measurements is affected by the thermal effect. In order to overcome this problem, we propose a modified sensor structure. With a fiber Bragg grating (FBG written in the insert fiber end of the Fabry-Perot cavity, the FBG acts as a temperature compensation unit for the magnetic field measurement and it provides an effective solution to the cross-sensitivity effect. The experimental results show that the sensitivity of magnetic field detection improves from 0.23 nm/mT to 0.53 nm/mT, and the magnetic field measurement resolution finally reaches 37.7 T. The temperature-compensated FP-FBG magnetic sensor has obvious advantages of small volume and high sensitivity, and it has a good prospect in applications in the power industry and national defense technology areas.

  12. Electronic Field Data Collection in Support of Satellite-Based Food Security Monitoring in Tanzania

    Science.gov (United States)

    Nakalembe, C. L.; Dempewolf, J.; Justice, C. J.; Becker-Reshef, I.; Tumbo, S.; Maurice, S.; Mbilinyi, B.; Ibrahim, K.; Materu, S.

    2016-12-01

    In Tanzania agricultural extension agents traditionally collect field data on agriculture and food security on paper, covering most villages throughout the country. The process is expensive, slow and cumbersome and prone to data transcription errors when the data get entered at the district offices into electronic spreadsheets. Field data on the status and condition of agricultural crops, the population's nutritional status, food storage levels and other parameters are needed in near realtime for early warning to make critical but most importantly timely and appropriate decisions that are informed with verified data from the ground. With the ubiquitous distribution of cell phones, which are now used by the vast majority of the population in Tanzania including most farmers, new, efficient and cost-effective methods for field data collection have become available. Using smartphones and tablets data on crop conditions, pest and diseases, natural disasters and livelihoods can be collected and made available and easily accessible in near realtime. In this project we implemented a process for obtaining high quality electronic field data using the GeoODK application with a large network of field extension agents in Tanzania and Uganda. These efforts contribute to work being done on developing an advanced agriculture monitoring system for Tanzania, incorporating traditional data collection with satellite information and field data. The outcomes feed directly into the National Food Security Bulletin for Tanzania produced by the Ministry of Agriculture as well as a form a firm evidence base and field scale monitoring of the disaster risk financing in Uganda.

  13. Holographic reconstruction of sound fields based on the acousto-optic effect

    DEFF Research Database (Denmark)

    Fernandez Grande, Efren; Torras Rosell, Antoni; Jacobsen, Finn

    2013-01-01

    yielding a full characterization of the sound field. In this study, a direct projection of the Radon transform from one plane to another and into the space domain, based on an elementary wave expansion is proposed. The relationship between the Radon and the wavenumber domains is examined......Recent studies have shown that it is possible to measure a sound field using acousto-optic tomography. Theacousto-optic effect, i.e., the interaction between sound and light, can be used to measure an arbitrary soundfield by scanning it with a laser Doppler vibrometer (LDV) over an aperture......; This can be described mathematically by means of the Radon transform of the acoustic field. An interesting feature of this Measurement technique is that the spatial characteristics of the sound field are captured in the measurement. Therefore, the technique has an inherent holographic potential, implicitly...

  14. Novel Magnetic Field Meter Based on Giant Magneto-impedance (GMI Effect

    Directory of Open Access Journals (Sweden)

    K. Nesteruk

    2006-03-01

    Full Text Available A novel magnetic field GMI-sensor/meter has been invented and designed. Its laboratory model was constructed and tested, demonstrating the sensitivity of 1.10–8 T (100 mGs. The principle of operation of this meter is based on changes of the quality factor of the resonance circuit a part of which is a magnetic GMI sensing element.These changes are due to variations in the real component of the impedance of this element caused by an external DC-field. The sensing element is in the form of a piece of the “non-magnetostrictive” amorphous ribbon. Magnetic field modulation of an acoustic frequency and feedback circuit (compensating field applied to the device, significantly increases stability and linearity of the measuring system.

  15. Scalable wide-field optical coherence tomography-based angiography for in vivo imaging applications.

    Science.gov (United States)

    Xu, Jingjiang; Wei, Wei; Song, Shaozhen; Qi, Xiaoli; Wang, Ruikang K

    2016-05-01

    Recent advances in optical coherence tomography (OCT)-based angiography have demonstrated a variety of biomedical applications in the diagnosis and therapeutic monitoring of diseases with vascular involvement. While promising, its imaging field of view (FOV) is however still limited (typically less than 9 mm(2)), which somehow slows down its clinical acceptance. In this paper, we report a high-speed spectral-domain OCT operating at 1310 nm to enable wide FOV up to 750 mm(2). Using optical microangiography (OMAG) algorithm, we are able to map vascular networks within living biological tissues. Thanks to 2,048 pixel-array line scan InGaAs camera operating at 147 kHz scan rate, the system delivers a ranging depth of ~7.5 mm and provides wide-field OCT-based angiography at a single data acquisition. We implement two imaging modes (i.e., wide-field mode and high-resolution mode) in the OCT system, which gives highly scalable FOV with flexible lateral resolution. We demonstrate scalable wide-field vascular imaging for multiple finger nail beds in human and whole brain in mice with skull left intact at a single 3D scan, promising new opportunities for wide-field OCT-based angiography for many clinical applications.

  16. A feature matching and fusion-based positive obstacle detection algorithm for field autonomous land vehicles

    Directory of Open Access Journals (Sweden)

    Tao Wu

    2017-03-01

    Full Text Available Positive obstacles will cause damage to field robotics during traveling in field. Field autonomous land vehicle is a typical field robotic. This article presents a feature matching and fusion-based algorithm to detect obstacles using LiDARs for field autonomous land vehicles. There are three main contributions: (1 A novel setup method of compact LiDAR is introduced. This method improved the LiDAR data density and reduced the blind region of the LiDAR sensor. (2 A mathematical model is deduced under this new setup method. The ideal scan line is generated by using the deduced mathematical model. (3 Based on the proposed mathematical model, a feature matching and fusion (FMAF-based algorithm is presented in this article, which is employed to detect obstacles. Experimental results show that the performance of the proposed algorithm is robust and stable, and the computing time is reduced by an order of two magnitudes by comparing with other exited algorithms. This algorithm has been perfectly applied to our autonomous land vehicle, which has won the champion in the challenge of Chinese “Overcome Danger 2014” ground unmanned vehicle.

  17. Active Graphene-Based Terahertz Dual-Band Modulator Implemented in the Presence of External Fields

    Science.gov (United States)

    Hu, Xiang; Huang, Qiuping; Zhao, Yi; Cai, Honglei; Lu, Yalin

    2017-07-01

    In this work, we numerically demonstrate a dynamic graphene-based dual-band metamaterial modulator (gDMM) in the presence of an external magnetic field and gate electric field. With the objective of modulating terahertz waves at two separate channels, we utilize the proposed dual-field control method to dynamically modulate the optical conductivity of graphene, and thus the working frequencies of the gDMM. An interpretation for such dependence on the external fields is presented based on a quantum understanding of the energy structure of graphene, and a numerical method based on the finite element method (FEM) is employed to investigate the optical responses of our proposed gDMM. Our results show that, by varying the strength of external fields, one can switch the operation status of the two working channels located at 3.18 THz and 9.04 THz, with modulation depths exceeding 84.4%. Only 30 meV of energy is required for shifting the Fermi level to accomplish the switch, which is extremely low compared with methods in previous works using gate electric control alone. Simultaneous ON/OFF statuses are also realized. Such great tunability and controllability of our proposed gDMM over a wide frequency range may give rise to a new class of dynamic devices for terahertz and microwave applications.

  18. Glocal Media and their Reception by Zambian Youth

    DEFF Research Database (Denmark)

    Wildermuth, Norbert

    and global media are still shaped by the particular conditions of everyday-life.                       In my paper, which is based on field research in Lusaka in October/November 2004, I will present some of the findings of my interview-based and observational investigation into the media uses of Lusaka......  Since 1990 Zambia has witnessed a dramatic enlargement of its media landscape. The emergence of cable and satellite television, private radio stations and an independent national press have been cornerstones in this development. Paralleled by a boom in information and communication technologies...... youth. A special focus will be on: (1) Isidingo, the most popular TV serial (of South African origin) offered by the national broadcaster ZNBC, and one of the few terrestrial TV programs which attract a substantial audience amongst local youth; (2) the Pentecostal Trinity Broadcasting Network, which...

  19. More than Decadence - Johannes Jørgensen's early reception of Arthur Schopenhauer

    DEFF Research Database (Denmark)

    Nord, Johan Christian

    Fremmedsproglig forskningsformidling af hovedpunkterne i artiklen "En Poet og en Religionsstifter, med hvem jeg er enig i næsten alle Ting" Indledende betragtninger over Johannes Jørgensens Schopenhauer-reception.......Fremmedsproglig forskningsformidling af hovedpunkterne i artiklen "En Poet og en Religionsstifter, med hvem jeg er enig i næsten alle Ting" Indledende betragtninger over Johannes Jørgensens Schopenhauer-reception....

  20. Policies and practices in the health-related reception of quota refugees in Denmark

    DEFF Research Database (Denmark)

    Frederiksen, Hanne W; Krasnik, Allan; Nørredam, Marie

    2012-01-01

    Quota refugees coming to Denmark are mandated refugee status offshore and approximately 500 quota refugees are resettled annually. Upon arrival to Denmark, quota refugees are received directly in the municipalities and municipal caseworkers therefore have the practical responsibility...... for their health-related reception. The aim of this study was to investigate the health-related reception of quota refugees in Denmark by focusing on the presence of municipal policies and practices, and to test for possible associations with these policies and practices....