Textile-to-rigid microstrip transition using permanent magnets

Exterior, general view with entrance sculptur

Textile‐to‐rigid microstrip transition using permanent magnets

A novel transition between a rigid-substrate and a flexible-substrate microstrip for use in wearable devices is described. The contact force between the conductors of the two microstrips is supplied by a pair of rectangular magnets. A simulation and measurement study carried out on a test jig comprising a back-to-back pair of such transitions demonstrated an insertion loss of better than 0.5 dB/transition can be achieved in the range of 0-3 GHz

Fabric based frequency selective surfaces using weaving and screen printing

This paper is a postprint of a paper submitted to and accepted for publication in Electronics Letters and is subject to Institution of Engineering and Technology Copyright. The copy of record is available at IET Digital Library at: http://dx.doi.org/10.1049/el.2013.2314Two examples of fabric based frequency selective surfaces (FSSs) are presented. The FSSs are produced by using screen printing and weaving. Both measured and simulated data are presented showing excellent agreement and performance for the FSSs when compared with the simulated data. The performance of these samples points towards a useful screening technique using fabric hangings and wall coverings in a range of applications where temporary electromagnetic wave ingress or egress needs to be controlled

Dimensionless cosmology

Although it is well known that any consideration of the variations of fundamental constants should be restricted to their dimensionless combinations, the literature on variations of the gravitational constant $G$ is entirely dimensionful. To illustrate applications of this to cosmology, we explicitly give a dimensionless version of the parameters of the standard cosmological model, and describe the physics of Big Bang Neucleosynthesis and recombination in a dimensionless manner. The issue that appears to have been missed in many studies is that in cosmology the strength of gravity is bound up in the cosmological equations, and the epoch at which we live is a crucial part of the model. We argue that it is useful to consider the hypothetical situation of communicating with another civilization (with entirely different units), comparing only dimensionless constants, in order to decide if we live in a Universe governed by precisely the same physical laws. In this thought experiment, we would also have to compare epochs, which can be defined by giving the value of any {\it one} of the evolving cosmological parameters. By setting things up carefully in this way one can avoid inconsistent results when considering variable constants, caused by effectively fixing more than one parameter today. We show examples of this effect by considering microwave background anisotropies, being careful to maintain dimensionlessness throughout. We present Fisher matrix calculations to estimate how well the fine structure constants for electromagnetism and gravity can be determined with future microwave background experiments. We highlight how one can be misled by simply adding $G$ to the usual cosmological parameter set

Effect of training on accumulated oxygen deficit and shuttle run performance

Etude des changements de paramètres au niveau physiologique, métabolique et des performances après un programme d'entraînement intensif de six semaines

Design and SAR Analysis of Wearable Antenna on Various Parts of Human Body, Using Conventional and Artificial Ground Planes

This is an Open-Access article published by The Korean Institute of Electrical Engineers distributed under the terms of the Creative Commons Attribution Non-Commercial 3.0 Unported License (CC BY-NC). Full details of this licence are available at: http://creativecommons.org/ licenses/by-nc/3.0/This paper presents design and specific absorption rate analysis of a 2.4 GHz wearable patch antenna on a conventional and electromagnetic bandgap (EBG) ground planes, under normal and bent conditions. Wearable materials are used in the design of the antenna and EBG surfaces. A woven fabric (Zelt) is used as a conductive material and a 3 mm thicker Wash Cotton is used as a substrate. The dielectric constant and tangent loss of the substrate are 1.51 and 0.02 respectively. The volume of the proposed antenna is 113×96.4×3 mm3. The metamaterial surface is used as a high impedance surface which shields the body from the hazards of electromagnetic radiations to reduce the Specific Absorption Rate (SAR). For on-body analysis a three layer model (containing skin, fats and muscles) of human arm is used. Antenna employing the EBG ground plane gives safe value of SAR (i.e. 1.77W/kg<2W/kg), when worn on human arm. This value is obtained using the safe limit of 2 W/kg, averaged over 10g of tissue, specified by the International Commission of Non Ionization Radiation Protection (ICNIRP). The SAR is reduced by 83.82% as compare to the conventional antenna (8.16 W/kg>2W/kg). The efficiency of the EBG based antenna is improved from 52 to 74%, relative to the conventional counterpart. The proposed antenna can be used in wearable electronics and smart clothing

Neutrophil Chemotaxis Defect in IgA Deficiency Evaluated by Migration Agarose Method

The chemotactic and random mobility functions of twelve selectively IgA-deficient patients were evaluated by a method using agarose gel. A severe polymorphonuclear cellular chemotactic defect was found in ten out of twelve patients, but only five of them also showed a marked associated impairment of random locomotory function. Futhermore, in one subject, levamisole therapy resulted in a dramatic improvement of both chemotactic and random mobility functions. These results are discussed in the paper with respect to the possible pathogenetic implications