Time for pulse traversal through slabs of dispersive and negative (ϵ\epsilon, μ\mu) materials

The traversal times for an electromagnetic pulse traversing a slab of dispersive and dissipative material with negative dielectric permittivity ($\epsilon$) and magnetic permeability ($\mu$) have been calculated by using the average flow of electromagnetic energy in the medium. The effects of bandwidth of the pulse and dissipation in the medium have been investigated. While both large bandwidth and large dissipation have similar effects in smoothening out the resonant features that appear due to Fabry-P\'{e}rot resonances, large dissipation can result in very small or even negative traversal times near the resonant frequencies. We have also investigated the traversal times and Wigner delay times for obliquely incident pulses and evanescent pulses. The coupling to slab plasmon polariton modes in frequency ranges with negative $\epsilon$ or $\mu$ is shown to result in large traversal times at the resonant conditions. We also find that the group velocity mainly contributes to the delay times for pulse propagating across a slab with n=-1. We have checked that the traversal times are positive and subluminal for pulses with sufficiently large bandwidths.Comment: 9 pages, 9 figures, Submitted to Phys. Rev.

Remote, non-contacting personnel bio-identification using microwave radiation

A system to remotely identify a person by utilizing a microwave cardiogram, where some embodiments segment a signal representing cardiac beats into segments, extract features from the segments, and perform pattern identification of the segments and features with a pre-existing data set. Other embodiments are described and claimed

Systems and methods for remote long standoff biometric identification using microwave cardiac signals

Systems and methods for remote, long standoff biometric identification using microwave cardiac signals are provided. In one embodiment, the invention relates to a method for remote biometric identification using microwave cardiac signals, the method including generating and directing first microwave energy in a direction of a person, receiving microwave energy reflected from the person, the reflected microwave energy indicative of cardiac characteristics of the person, segmenting a signal indicative of the reflected microwave energy into a waveform including a plurality of heart beats, identifying patterns in the microwave heart beats waveform, and identifying the person based on the identified patterns and a stored microwave heart beats waveform

Robotic sensorimotor interaction strategies

Abstract. In this thesis we investigate the mathematical modeling of cognition using sensorimotor transition systems. The focus of the thesis is enactivism, where an agent learns to think through actions. As a theoretical basis for our implementation, we discuss a mathematical model of enactivist cognition, sensorimotor interaction and how they can be used as algorithmic aides for studying theoretical problems in robotic systems. In Chapter 3 of this thesis, we introduce a platform which was developed in the University of Oulu as a software project and explain how enactivism and sensorimotor interaction have been taken advantage of, in developing a 2D platform. This platform enables one to concretely implement and explore different interaction strategies that allow an agent to construct internal models of its surroundings. The agent in the platform is a multi-jointed robotic arm, which maneuvers through an obstacle-filled environment. The robotic arm tries to explore its environment with minimal sensory feedback, using algorithms created by the user of the platform. Our main goal on this thesis is to implement new features to this platform. We implement a memory functionality which allows the robotic arm to store all its performed actions. The memory helps the agent infer to a greater extent its surroundings from a limited sequence of action-observation pairs, and helps it in getting a better grasp of the environment. In addition, we implement other methods and functionalities, such as an obstacle sensor, a graph visualization of the internal models, etc. to enhance the perceptual ability of the robotic arm. In Section 5, we develop an algorithm for a simple 2D environment with no obstacles. Here the robotic arm makes a 360-degree move in four steps to perceive its surroundings and generates a state machine graph to visualize its internal model of the environment. The goal of the algorithm is to build an accurate representation of the environment with the help of memory. Through this algorithm we are able to evaluate the performance of the newly implemented features. We also test the platform through unit testing for finding and resolving bugs.Sensorimotoriset vuorovaikutusstrategiat robotiikassa. Tiivistelmä. Tässä tutkielmassa tutkimme kognition matemaattista mallintamista käyttämällä sensorimotorisia transitio-järjestelmiä. Tutkielman keskiössä on enaktivismi, jossa agentti oppii ajattelemaan toiminnan kautta. Teoreettisena perustana toteutuksellemme käsittelemme matemaattista mallia enaktivistisesta kognitiosta, sensorimotorista vuorovaikutusta ja kuinka niitä voidaan käyttää algoritmien apuvälineinä teoreettisten ongelmien tutkimisessa robottiikkajärjestelmissä. Tutkielman luvussa 3 esittelemme alustan, joka on kehitetty Oulun yliopistossa ohjelmistoprojektina, ja selittämme miten enaktivismia ja sensomotorista vuorovaikutusta on hyödynnetty 2D-alustan kehittämisessä. Alusta mahdollistaa erilaisten vuorovaikutusstrategioiden konkreettisen toteuttamisen ja tutkimisen. Näiden avulla agentti rakentaa sisäisiä malleja ympäristöstään. Alustassa mallinnettu agentti on moninivelinen robottikäsi, joka liikkuu esteitä sisältävässä ympäristössä. Robottikäsi pyrkii tutkimaan ympäristöään minimaalisen sensoritiedon avulla käyttämällä alustan käyttäjän luomia algoritmeja. Tutkielmamme päätavoite on kehittää uusia ominaisuuksia tälle alustalle. Toteutamme muistitoiminnallisuuden, jonka avulla robottikäsi tallentaa kaikki suoritetut toiminnot. Muisti auttaa agenttia päättelemään enemmän ympäristöstään rajoitettujen toiminta-havainto-parien avulla, ja auttaa sitä ympäristön hahmottamisessa. Lisäksi kehitämme muita menetelmiä ja toiminnallisuuksia kuten estesensorin ja sisäisten mallien graafisen visualisoinnin parantaaksemme robottikäden havainnointikykyä. Tutkielman myöhemmässä osassa kehitämme algoritmin yksinkertaiselle 2D-ympäristölle ilman esteitä. Siinä robottikäsi tekee 360 asteen liikkeen neljässä vaiheessa havainnoidakseen ympäristönsä, ja luo tilasiirtymäkaavion visualisoidakseen sisäisen mallinsa ympäristöstä. Algoritmin tavoitteena on rakentaa tarkka malli ympäristöstä muistin avulla. Tämän algoritmin avulla pystymme arvioimaan kehittämiemme uusien ominaisuuksien toimintaa. Testaamme alustaa myös yksikkötesteillä löytääksemme ja korjataksemme virheitä

Natural organic matter in sedimentary basins and its relation to arsenic in anoxic ground water: the example of West Bengal and its worldwide implications

In order to investigate the mechanism of As release to anoxic ground water in alluvial aquifers, the authors sampled ground waters from 3 piezometer nests, 79 shallow (80 m) wells, in an area 750 m by 450 m, just north of Barasat, near Kolkata (Calcutta), in southern West Bengal. High concentrations of As (200-1180 mug L-1) are accompanied by high concentrations of Fe (3-13.7 mgL(-1)) and PO4 (1-6.5 mg L-1). Ground water that is rich in Mn (1-5.3 mg L-1) contains <50 mug L-1 of As. The composition of shallow ground water varies at the 100-m scale laterally and the metre-scale vertically, with vertical gradients in As concentration reaching 200 mug L-1 m(-1). The As is supplied by reductive dissolution of FeOOH and release of the sorbed As to solution. The process is driven by natural organic matter in peaty strata both within the aquifer sands and in the overlying confining unit. In well waters, thermotolerant coliforms, a proxy for faecal contamination, are not present in high numbers (<10 cfu/100 ml in 85% of wells) showing that faecally-derived organic matter does not enter the aquifer, does not drive reduction of FeOOH, and so does not release As to ground water.Arsenic concentrations are high (much greater than50 mug L-1) where reduction of FeOOH is complete and its entire load of sorbed As is released to solution, at which point the aquifer sediments become grey in colour as FeOOH vanishes. Where reduction is incomplete, the sediments are brown in colour and resorption of As to residual FeOOH keeps As concentrations below 10 mug L-1 in the presence of dissolved Fe. Sorbed As released by reduction of Mn oxides does not increase As in ground water because the As resorbs to FeOOH. High concentrations of As are common in alluvial aquifers of the Bengal Basin arise because Himalayan erosion supplies immature sediments, with low surface-loadings of FeOOH on mineral grains, to a depositional environment that is rich in organic mater so that complete reduction of FeOOH is common. (C) 2004 Published by Elsevier Ltd

Complete Mitochondrial Genome Sequence of the Magpie-Lark (Grallina cyanoleuca)

Here, we report the complete mitochondrial genome sequence of an Australian passerine bird, magpie-lark (Grallina cyanoleuca). The circular genome has a size of 16,933 bp and contains 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes. This study provides a reference mitochondrial genome of magpie-lark for further molecular studies

Early Marriage in Bangladesh: A Cross-Sectional Study Exploring the Associated Factors

This cross-sectional study intends to explore the factors associated with the prevalence of early marriage among female teenagers in Bangladesh. Data from the Bangladesh Demographic and Health Survey (BDHS, 2014) were used to meet the study objective. Two binary logistic models were run to estimate the factors that influence early marriage. In Model-I, the covariates were considered in a bivariate setup, and unadjusted odds ratios (UOR) were obtained from ModelII, where all the covariates were taken into account to get the adjusted odds ratio. Results show that the level of education for both females and their partners, religiosity, possession of wealth and geographical location are some important factors with significant effects on the prevalence of early marriage in Bangladesh. Based on the findings, this study recommends gearing up provisions of education for all, awareness-building through social mobilization, reform initiatives concerning Islamic beliefs and strengthening poverty-reduction strategies to speed up the process of eliminating early marriage