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Input Patterns (input + pattern)
Selected AbstractsInput mapping algorithm for parallel transistor structuresINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 7 2009Spiridon NikolaidisArticle first published online: 17 JUL 200 Abstract A new algorithm for mapping every possible input pattern of a parallel transistor structure to an equivalent set of normalized inputs (having the same starting and ending point) is introduced. This algorithm is based on the analysis of the operation of the transistor structure and can be used for the development of analytical timing models for CMOS circuits. Simulation results show a very good accuracy of the algorithm. Copyright © 2008 John Wiley & Sons, Ltd. [source] Symmetric synaptic patterns between starburst amacrine cells and direction selective ganglion cells in the rabbit retinaTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2008Yung-Cheng Chen Abstract Inputs from starburst amacrine cells (SACs) to ON-OFF direction selective ganglion cells (DSGCs) in the rabbit retina are themselves directional. However, the synaptic asymmetry between SACs and DSGCs required for generating direction selectivity has been controversial. We investigated dendritic contacts and distribution of inhibitory synapses between SACs and their overlapped DSGCs. Double injection of SAC/DSGC pairs and quantitative analysis revealed no obvious asymmetry of dendritic contacts between SACs and DSGCs. Furthermore, examination of the inhibitory input pattern on the dendrites of DSGCs using antibodies against GABAA receptors also suggested an isotropic arrangement with the overlapping SACs in both the preferred and the null directions. Therefore, the presynaptic mechanism of direction selectivity upon DSGCs may not result from a simple asymmetric arrangement with overlapping SACs. Multiple layer interactions and sophisticated synaptic connections between SACs and DSGCs are necessary. J. Comp. Neurol. 508:175,183, 2008. © 2008 Wiley-Liss, Inc. [source] A brainlike learning system with supervised, unsupervised, and reinforcement learningELECTRICAL ENGINEERING IN JAPAN, Issue 1 2008Takafumi Sasakawa Abstract According to Hebb's cell assembly theory, the brain has the capability of function localization. On the other hand, it is suggested that in the brain there are three different learning paradigms: supervised, unsupervised, and reinforcement learning, which are related deeply to the three parts of brain: cerebellum, cerebral cortex, and basal ganglia, respectively. Inspired by the above knowledge of the brain in this paper we present a brainlike learning system consisting of three parts: supervised learning (SL) part, unsupervised learning (UL) part, and reinforcement learning (RL) part. The SL part is a main part learning input,output mapping; the UL part is a competitive network dividing input space into subspaces and realizes the capability of function localization by controlling firing strength of neurons in the SL part based on input patterns; the RL part is a reinforcement learning scheme, which optimizes system performance by adjusting the parameters in the UL part. Numerical simulations have been carried out and the simulation results confirm the effectiveness of the proposed brainlike learning system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(1): 32,39, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20600 [source] Emerging pollutants in the North Sea in comparison to Lake Ontario, Canada, dataENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2007Jens Arne Andresen Abstract In the present study, the concentrations and fate of contaminants such as organophosphate flame retardants and plasticizers, musk compounds such as galaxolide (HHCB), tonalide (AHTN), musk ketone and musk xylene, the bactericide triclosan, as well as the metabolites HHCB-lactone and triclosan-methyl were compared in the aqueous phase of the German Bight (North Sea). The concentrations of these compounds were around 1 to 10 ng/L in nearshore areas, and the concentrations were lower in the more pristine areas. The highest concentrations were determined for tris-(2-chloro- isopropyl) phosphate in the North Sea with concentration exceeding 10 ng/L even for the offshore samples. The samples contained 1 to 20 ng/L chlorinated organophosphates, approximately 1 ng/L nonchlorinated organophosphates, and 0.3 to 3 ng/L fragrance compounds. Some samples from Lake Ontario (Canada) were analyzed in comparison. Per capita emissions were calculated for both regions. These emissions were compared and turned out to be very similar for the Canadian and German locations. For the North Sea, some observations concerning stability, dilution, and degradation, as well as sources of the respective substances, were performed. These data indicate that the chlorinated organophosphates and some musk fragrances exhibit half lives exceeding the residence times and thus can be considered to be persistent in this ecosystem. In the German Bight, the river Elbe is the dominating source for the more hydrophilic compounds, such as chlorinated organophosphate flame retardants, which are diluted only into the North Sea. However, for the more lipophilic compounds such as the musk fragrances, different input patterns as well as distribution patterns are relevant, though the river Elbe is still a major source of pollution to the German Bight of the North Sea. The data seem to indicate either relevant inputs further west of the sampling area or mobilization from the sediments. [source] Relation of apical dendritic spikes to output decision in CA1 pyramidal cells during synchronous activation: a computational studyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2006José M. Ibarz Abstract Recent studies on the initiation and propagation of dendritic spikes have modified the classical view of postsynaptic integration. Earlier we reported that subthreshold currents and spikes recruited by synaptic currents play a critical role in defining outputs following synchronous activation. Experimental factors strongly condition these currents due to their nonlinear behaviour. Hence, we have performed a detailed parametric study in a CA1 pyramidal cell model to explore how different variables interact and initiate dendritic spiking, and how they influence cell output. The input pattern, the relative excitability of axon and dendrites, the presence/modulation of voltage-dependent channels, and inhibition were cross analysed. Subthreshold currents and spikes on synaptically excited branches fired spikes in other branches to jointly produce different modalities of apical shaft spiking with a variable impact on cell output. Synchronous activation initiated a varying number and temporal scatter of firing branches that produced in the apical shaft-soma axis nonpropagating spikes, pseudosaltatory or continuous forward conduction, or backpropagation. As few as 6,10 local spikes within a time window of 2 ms ensure cell output. However, the activation mode varied extremely when two or more variables were cross-analysed, becoming rather unpredictable when all the variables were considered. Spatially clustered inputs and upper modulation of dendritic Na+ or Ca2+ electrogenesis favour apical decision. In contrast, inhibition biased the output decision toward the axon and switched between dendritic firing modes. We propose that dendrites can discriminate input patterns and decide immediate cell output depending on the particular state of a variety of endogenous parameters. [source] Innervation of interneurons immunoreactive for VIP by intrinsically bursting pyramidal cells and fast-spiking interneurons in infragranular layers of juvenile rat neocortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002Jochen F. Staiger Abstract Cortical columns contain specific neuronal populations with characteristic sets of connections. This wiring forms the structural basis of dynamic information processing. However, at the single-cell level little is known about specific connectivity patterns. We performed experiments in infragranular layers (V and VI) of rat somatosensory cortex, to clarify further the input patterns of inhibitory interneurons immunoreactive (ir) for vasoactive intestinal polypeptide (VIP). Neurons in acute slices were electrophysiologically characterized using whole-cell recordings and filled with biocytin. This allowed us to determine their firing pattern as regular-spiking, intrinsically bursting and fast-spiking, respectively. Biocytin was revealed histochemically and VIP immunohistochemically. Sections were examined for contacts between the axons of the filled neurons and the VIP-ir targets. Twenty pyramidal cells and five nonpyramidal (inter)neurons were recovered and sufficiently stained for further analysis. Regular-spiking pyramidal cells displayed no axonal boutons in contact with VIP-ir targets. In contrast, intrinsically bursting layer V pyramidal cells showed four putative single contacts with a proximal dendrite of VIP neurons. Fast-spiking interneurons formed contacts with two to six VIP neurons, preferentially at their somata. Single as well as multiple contacts on individual target cells were found. Electron microscopic examinations showed that light-microscopically determined contacts represent sites of synaptic interactions. Our results suggest that, within infragranular local cortical circuits, (i) fast-spiking interneurons are more likely to influence VIP cells than are pyramidal cells and (ii) pyramidal cell input probably needs to be highly convergent to fire VIP target cells. [source] Design and implementation of a new neural network-based high speed distance relayEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2008M. Sanaye-Pasand Abstract This paper presents a new neural network-based transmission line distance protection module. The proposed module uses samples of voltage and current signals to learn the hidden relationship existing in the input patterns. Using a power system model, simulation studies are preformed and influence of changing system parameters such as fault resistance and power flow direction is studied. The proposed neural network has also been implemented on a digital signal processor (DSP) board and its behavior is investigated using suitable developed hardware. Details of the implementation and experimental studies are given in the paper. Performance studies results show that the proposed algorithm is able to distinguish various transmission line faults rapidly and correctly. It shows that the proposed network is fast, reliable, and accurate. Copyright © 2007 John Wiley & Sons, Ltd. [source] Processing English Compounds in the First and Second Language: The Influence of the Middle MorphemeLANGUAGE LEARNING, Issue 1 2010Victoria A. Murphy Native English speakers tend to exclude regular plural inflection when producing English noun-noun compounds (e.g.,,rat-eater,not,rats-eater) while allowing irregular plural inflection within compounds (e.g.,,mice-eater) (Clahsen, 1995; Gordon, 1985; Hayes, Smith & Murphy, 2005; Lardiere, 1995; Murphy, 2000). Exposure to the input alone has been considered insufficient to explain this dissociation between regular and irregular plurals in compounds because naturally occurring compounds in English rarely have plurals of any type included within them (e.g., Gordon, 1985). However, the constraint on the production of plural inflection in English compounds could be derived from the patterns in which regular plural and possessive morphemes occur in the input. To explore this idea, native adult English speakers and adult Chinese learners of English were asked to process a series of compounds containing different medial morphemes and phonemes. Comparisons were made across compounds with regular and irregular plurals and possessive [-s]. Native speakers (NS) of English processed compounds with medial possessive morphology faster than compounds with medial regular plural morphology. The second language learners did not show the same pattern as the NSs, which could be due to the fact that they had considerably less exposure to the relevant input patterns relative to the NSs. Regular plurals may be excluded before a rightmost noun in English because the pattern "Noun,[-s] morpheme,Noun" is more frequently used for marking possession in English. Irregular plurals do not end in the [-s] morpheme and therefore do not "compete" with the possessive marker and, consequently, may be optionally included in compounds. It is possible, therefore, that the input English learners receive could indeed be sufficient to constrain this aspect of English compound production. [source] | |||||||||||||