Tracking-Optimized Quantization for H.264 Compression in Transportation Video Surveillance Applications

We propose a tracking-aware system that removes video components of low tracking interest and optimizes the quantization during compression of frequency coefficients, particularly those that most influence trackers, significantly reducing bitrate while maintaining comparable tracking accuracy. We utilize tracking accuracy as our compression criterion in lieu of mean squared error metrics. The process of optimizing quantization tables suitable for automated tracking can be executed online or offline. The online implementation initializes the encoding procedure for a specific scene, but introduces delay. On the other hand, the offline procedure produces globally optimum quantization tables where the optimization occurs for a collection of video sequences. Our proposed system is designed with low processing power and memory requirements in mind, and as such can be deployed on remote nodes. Using H.264/AVC video coding and a commonly used state-of-the-art tracker we show that while maintaining comparable tracking accuracy our system allows for over 50% bitrate savings on top of existing savings from previous work

Spectral analysis of GEOS-3 altimeter data and frequency domain collocation

The mathematical background in spectral analysis as applied to geodetic applications is summarized. The resolution (cut-off frequency) of the GEOS 3 altimeter data is examined by determining the shortest wavelength (corresponding to the cut-off frequency) recoverable. The data from some 18 profiles are used. The total power (variance) in the sea surface topography with respect to the reference ellipsoid as well as with respect to the GEM-9 surface is computed. A fast inversion algorithm for matrices of simple and block Toeplitz matrices and its application to least squares collocation is explained. This algorithm yields a considerable gain in computer time and storage in comparison with conventional least squares collocation. Frequency domain least squares collocation techniques are also introduced and applied to estimating gravity anomalies from GEOS 3 altimeter data. These techniques substantially reduce the computer time and requirements in storage associated with the conventional least squares collocation. Numerical examples given demonstrate the efficiency and speed of these techniques

The Road to Self-Improvement; A Mother and Son story

Eren Denburg Niederhoffer and his Mother Dorian Denburg will discuss: -Eren\u27s story of his pursuit of self-improvement as a man on the Autism Spectrum-The lessons he learned along the way while struggling with autism-What he has accomplished as a man with autism-What families of children and young adults with and without autism in their family can stand to benefit through Eren and Dorian\u27s story and advice

The fluctuating resource hypothesis explains invasibility, but not exotic advantage following disturbance

Invasibility is a key indicator of community susceptibility to changes in structure and function. The fluctuating resource hypothesis (FRH) postulates that invasibility is an emergent community property, a manifestation of multiple processes that cannot be reliably predicted by individual community attributes like diversity or productivity. Yet, research has emphasized the role of these individual attributes, with the expectation that diversity should deter invasibility and productivity enhance it. In an effort to explore how these and other factors may influence invasibility, we evaluated the relationship between invasibility and species richness, productivity, resource availability, and resilience in experiments crossing disturbance with exotic seed addition in 1-m2 plots replicated over large expanses of grasslands in Montana, USA and La Pampa, Argentina. Disturbance increased invasibility as predicted by FRH, but grasslands were more invasible in Montana than La Pampa whether disturbed or not, despite Montana´s higher species richness and lower productivity. Moreover, invasibility correlated positively with nitrogen availability and negatively with native plant cover. These patterns suggested that resource availability and the ability of the community to recover from disturbance (resilience) better predicted invasibility than either species richness or productivity, consistent with predictions from FRH. However, in ambient, unseeded plots in Montana, disturbance reduced native cover by >50% while increasing exotic cover >200%. This provenance bias could not be explained by FRH, which predicts that colonization processes act on species? traits independent of origins. The high invasibility of Montana grasslands following disturbance was associated with a strong shift from perennial to annual species, as predicted by succession theory. However, this shift was driven primarily by exotic annuals, which were more strongly represented than perennials in local exotic vs. native species pools. We attribute this provenance bias to extrinsic biogeographic factors such as disparate evolutionary histories and/or introduction filters selecting for traits that favor exotics following disturbance. Our results suggest that (1) invasibility is an emergent property best explained by a community´s efficiency in utilizing resources, as predicted by FRH but (2) understanding provenance biases in biological invasions requires moving beyond FRH to incorporate extrinsic biogeographic factors that may favor exotics in community assembly.Fil: Pearson, Dean. United State Forest Service; Estados Unidos. University of Montana; Estados UnidosFil: Ortega, Yvette K.. United State Forest Service; Estados UnidosFil: Villarreal, Diego. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Lekberg, Ylva. University of Montana; Estados UnidosFil: Cock, Marina Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Eren, Ozkan. Adnan Menderes Universitesi; TurquíaFil: Hierro, Jose Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentin

Estimating the Richness of a Population When the Maximum Number of Classes Is Fixed: A Nonparametric Solution to an Archaeological Problem

Background: Estimating assemblage species or class richness from samples remains a challenging, but essential, goal. Though a variety of statistical tools for estimating species or class richness have been developed, they are all singly-bounded: assuming only a lower bound of species or classes. Nevertheless there are numerous situations, particularly in the cultural realm, where the maximum number of classes is fixed. For this reason, a new method is needed to estimate richness when both upper and lower bounds are known. Methodology/Principal Findings: Here, we introduce a new method for estimating class richness: doubly-bounded confidence intervals (both lower and upper bounds are known). We specifically illustrate our new method using the Chao1 estimator, rarefaction, and extrapolation, although any estimator of asymptotic richness can be used in our method. Using a case study of Clovis stone tools from the North American Lower Great Lakes region, we demonstrate that singly-bounded richness estimators can yield confidence intervals with upper bound estimates larger than the possible maximum number of classes, while our new method provides estimates that make empirical sense. Conclusions/Significance: Application of the new method for constructing doubly-bound richness estimates of Clovis stone tools permitted conclusions to be drawn that were not otherwise possible with singly-bounded richness estimates, namely, that Lower Great Lakes Clovis Paleoindians utilized a settlement pattern that was probably more logistical in nature than residential. However, our new method is not limited to archaeological applications. It can be applied to any set of data for which there is a fixed maximum number of classes, whether that be site occupancy models, commercial products (e.g. athletic shoes), or census information (e.g. nationality, religion, age, race)

Factors affecting Acheulean handaxe variation: Experimental insights, microevolutionary processes, and macroevolutionary outcomes

PublishedJournal ArticleThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.The “Acheulean” is comprised of individual knapping events undertaken by individual hominins. In other words, it is a particular component of hominin behavior that we draw out and amalgamate into a wider “pattern.” The resultant phenomenon (i.e., “the Acheulean”) is an entity that stretches over the space of three continents and spans a time period in excess of one million years. If such an exercise has any merit, it is because it provides a means of comparative (behavioral) analysis over these swathes of time and space. Comparative research can document, measure, and statistically assess temporo-spatial patterns of artifactual variation, and so test hypotheses regarding the character of that variation. However, it does not provide an independent means of examining some of the key phenomena which it is necessary to further understand in order to increase our comprehension of this archaeological legacy. Here, we review and synthesize recent experimental work that we have undertaken, which has specifically investigated some of the factors potentially responsible for the generation and constraint of variation within the Acheulean techno-complex. We examine issues of raw material, copying errors, and their relationship to mechanisms of social learning. Understanding these microevolutionary factors via experiments, we contend, is essential in order to reach a secure understanding of the macroscale phenomenon typically referred to as the “Acheulean.” Moreover, we outline how a “quantitative genetic” framework to these issues provides an essential means of linking these inherent micro- and macro-evolutionary factors into a coherent whole, while also simultaneously reconciling the potential influence of different sources of variation that are part of a temporally and geographically dispersed entity such as the Acheulean.We thank Marie-Hélène Moncel and Daniele Schreve for their invitation to take part in this issue. We are also grateful to the four reviewers (Michael O'Brien and three anonymous), whose thoughtful and constructive comments on the manuscript were much appreciated. Much of the work reported in this paper was funded by the Leverhulme Trust

Encoded and updated spatial working memories share a common representational format in alpha activity

Working memory (WM) flexibly updates information to adapt to the dynamic environment. Here, we used alpha-band activity in the EEG to reconstruct the content of dynamic WM updates and compared this representational format to static WM content. An inverted encoding model using alpha activity precisely tracked both the initially encoded position and the updated position following an auditory cue signaling mental updating. The timing of the update, as tracked in the EEG, correlated with reaction times and saccade latency. Finally, cross-training analyses revealed a robust generalization of alpha-band reconstruction of WM contents before and after updating. These findings demonstrate that alpha activity tracks the dynamic updates to spatial WM and that the format of this activity is preserved across the encoded and updated representations. Thus, our results highlight a new approach for measuring updates to WM and show common representational formats during dynamic mental updating and static storage

Quantifying Robotic Swarm Coverage

In the field of swarm robotics, the design and implementation of spatial density control laws has received much attention, with less emphasis being placed on performance evaluation. This work fills that gap by introducing an error metric that provides a quantitative measure of coverage for use with any control scheme. The proposed error metric is continuously sensitive to changes in the swarm distribution, unlike commonly used discretization methods. We analyze the theoretical and computational properties of the error metric and propose two benchmarks to which error metric values can be compared. The first uses the realizable extrema of the error metric to compute the relative error of an observed swarm distribution. We also show that the error metric extrema can be used to help choose the swarm size and effective radius of each robot required to achieve a desired level of coverage. The second benchmark compares the observed distribution of error metric values to the probability density function of the error metric when robot positions are randomly sampled from the target distribution. We demonstrate the utility of this benchmark in assessing the performance of stochastic control algorithms. We prove that the error metric obeys a central limit theorem, develop a streamlined method for performing computations, and place the standard statistical tests used here on a firm theoretical footing. We provide rigorous theoretical development, computational methodologies, numerical examples, and MATLAB code for both benchmarks.Comment: To appear in Springer series Lecture Notes in Electrical Engineering (LNEE). This book contribution is an extension of our ICINCO 2018 conference paper arXiv:1806.02488. 27 pages, 8 figures, 2 table

A simulation tool for better management of retinal services

Background: Advances in the management of retinal diseases have been fast-paced as new treatments become available, resulting in increasing numbers of patients receiving treatment in hospital retinal services. These patients require frequent and long-term follow-up and repeated treatments, resulting in increased pressure on clinical workloads. Due to limited clinic capacity, many National Health Service (NHS) clinics are failing to maintain recommended follow-up intervals for patients receiving care. As such, clear and robust, long term retinal service models are required to assess and respond to the needs of local populations, both currently and in the future. Methods: A discrete event simulation (DES) tool was developed to facilitate the improvement of retinal services by identifying efficiencies and cost savings within the pathway of care. For a mid-size hospital in England serving a population of over 500,000, we used 36 months of patient level data in conjunction with statistical forecasting and simulation to predict the impact of making changes within the service. Results: A simulation of increased demand and a potential solution of the 'Treat and Extend' (T&E) regimen which is reported to result in better outcomes, in combination with virtual clinics which improve quality, effectiveness and productivity and thus increase capacity is presented. Without the virtual clinic, where T&E is implemented along with the current service, we notice a sharp increase in the number of follow-ups, number of Anti-VEGF injections, and utilisation of resources. In the case of combining T&E with virtual clinics, there is a negligible (almost 0%) impact on utilisation of resources. Conclusions: Expansion of services to accommodate increasing number of patients seen and treated in retinal services is feasible with service re-organisation. It is inevitable that some form of initial investment is required to implement service expansion through T&E and virtual clinics. However, modelling with DES indicates that such investment is outweighed by cost reductions in the long term as more patients receive optimal treatment and retain vision with better outcomes. The model also shows that the service will experience an average of 10% increase in surplus capacity.Peer reviewedFinal Published versio

Exchange rates and stock markets in emerging economies: new evidence using the Quantile-on-Quantile approach

This study aims to reconsider the relationship between exchange rate and stock market returns for selected emerging countries. The quantile-on-quantile approach is employed to present an inclusive and detailed image of the association between the variables under investigation. This approach can reveal the heterogeneous and the varying relationship between the variables at different quantiles. The estimation outcome demonstrates that the examined countries’ stock market performances are not affected by the exchange rate changes unless certain market conditions are established. The empirical results suggest that the exchange rate flexibility has a crucial role in determining the market returns depending on the bearish or bullish conditions. Considering the asymmetric nature of the relationship between the exchange rate and the stock market, presented results can aid governmental authorities and investors to design dynamic economic policies and investment strategies