Place cell activity of hippocampal pyramidal cells has been described as the cognitive substrate spatial memory. Replay is observed during sharp-wave-ripple-associated population burst events (PBEs) and critical for consolidation recall-guided behaviors. PBE historically analyzed a phenomenon subordinate to place code. Here, we use hidden Markov models study PBEs in rats exploration both linear mazes open fields. We demonstrate that estimated are consistent with map environment, can even...

[1] Two different implementations of Gaussian process (GP) models are proposed to estimate the vertical total electron content (TEC) from dual frequency Global Positioning System (GPS) measurements. The model falseness GP and neural network compared using daily GPS TEC data Sutherland, South Africa, it is shown that exhibit superior falseness. approach has several advantages over previously developed approaches, which include seamless incorporation prior knowledge, a theoretically principled...

Human settlement expansion is one of the most pervasive forms land-cover change in South Africa. The use Page's cumulative sum (CUSUM) test proposed as a method to detect new developments areas that were previously covered by natural vegetation using 500-m Moderate Resolution Imaging Spectroradiometer time-series satellite data. sequential per-pixel alarm algorithm can take into account positive detection delay, probability detection, and false-alarm construct threshold. Simulated data...

It is proposed that the time series extracted from moderate resolution imaging spectroradiometer satellite data be modeled as a simple harmonic oscillator with additive colored noise. The noise an Ornstein-Uhlenbeck process. Fourier transform and maximum-likelihood parameter estimation are used to estimate parameters of oscillator. Two case studies in South Africa show reliable class differentiation can obtained between natural vegetation settlement land cover types, when using input...

The ability to modulate neural activity in a closed-loop fashion enables causal tests of hypotheses which link dynamically-changing circuits specific behavioral functions. One such circuit is the hippocampus, momentary sharp-wave ripple (SWR) events-≈ 100 ms periods large 150-250 Hz oscillations-have been linked mnemonic functions via selective perturbation. limited duration SWR means that latency systems used for interaction significant consequence compared other longer-lasting states....

Systematic Luby Transform (fountain) codes are investigated as a possible incremental redundancy scheme for EDGE. The convolutional currently used by EDGE is replaced the fountain approach. results of simulations performed each show that approach outperforms on second retransmission when implemented platform. also indicate if packet sizes specific platform large enough will always outperform

Abstract The place cell activity of hippocampal pyramidal cells has been described as the cognitive map substrate spatial memory. Replay is observed during sharp-wave ripple-associated population burst events and critical for consolidation recall-guided behaviors. To present, event (PBE) analyzed a phenomenon subordinate to code. Here, we use hidden Markov models study PBEs exploration both linear mazes open fields. We demonstrate that estimated are consistent with temporal replay sequences...

Three minimum-error land cover classifiers are compared on coarse resolution MODerate-resolution Imaging Spectroradiometer (MODIS) surface reflectance data for discerning between vegetation and settlement classes. It is shown that good class separability can be achieved using only the seasonal component of Normalized Difference Vegetation Index (NDVI) data, or mean several other MODIS bands. also why particular fail in certain spectral Finally it after NDVI, band 2 has highest all bands, 5...

Abstract Spike sorting is a standard preprocessing step to obtain ensembles of single unit data from multiunit, multichannel recordings in neuroscience. However, more recently, some researchers have started doing analyses directly on the unsorted data. Here we present new computational model that an extension (unsupervised) switching Poisson hidden Markov (where observations are time-binned spike counts each N neurons), clusterless approximation which observe only d -dimensional mark for...

In this letter, a first-order Moderate Resolution Imaging Spectroradiometer time-series simulator, which uses colored simple harmonic oscillator, is proposed. The simulated data can be used to augment sets so that intensive classification and change detection algorithms applied without enlarging the available ground truth sets. simulator's validity tested by simulating of natural vegetation human settlement areas comparing it with in Gauteng province located South Africa. difference found...

Abstract We use Cavalieri's principle to develop a novel integration technique which we call Cavalieri integration. integrals differ from Riemann in that non-rectangular strips are used. In this way can single find the areas of some interesting regions for it is difficult construct integrals. also present two methods evaluating integral by first transforming either an equivalent or Riemann-Stieltjes using special transformation functions h(x) and its inverse g(x), respectively. Interestingly...

In this paper a sequential time-varying maximum likelihood classifier is applied on coarse resolution MODIS surface reflectance data. It shown that good class separability can be obtained after considering only one year of Finally it NDVI, band 2 has the highest all land bands, and 6 lowest for presented case study.

Abstract Transient neural activity pervades hippocampal electrophysiological activity. During more quiescent states, brief ≈100 ms periods comprising large ≈150–250 Hz oscillations known as sharp-wave ripples (SWR) which co-occur with ensemble bursts of spiking activity, are regularly found in local field potentials recorded from area CA1. SWRs and their concomitant thought to be important for memory consolidation, recall, memory-guided decision making. Temporally-selective manipulations...

We propose a novel sequence score to determine what extent neural activity is consistent with trajectories through latent ensemble states - virtual place fields in an associated environment. In particular, we show how hidden Markov models (HMMs) can be used model and analyze sequences of activity, the resulting joint probability observation underlying naturally lead development two component which sequential contextual information are decoupled. also this discriminate between true shuffled...

The activity of ensembles neurons within the hippocampus is thought to enable memory formation, storage, recall, and potentially decision making. During offline states (associated with sharp wave ripples, quiescence, or sleep), some these are reactivated in temporally-ordered sequences which associations across time episodic memories spanning longer periods. However, analyzing neural remains challenging. Here we build on recent approaches using latent variable models for hippocampal...

Special cases of the belief propagation algorithm are commonly used to decode various linear error correcting codes. We show that can also be applied decoding problem for nonlinear codes by considering a modified set update rules. demonstrate applying it well-known Nordstrom-Robinson (15, 256, 5) code. The code contains many cycles, which means is suboptimal. Nevertheless, we observe coding gain about 1.2 dB with this method.