Wearable Energy Generating and Storing Textile Based on Carbon Nanotube Yarns

The challenges of textiles that can generate and store energy simultaneously for wearable devices are to fabricate yarns that generate electrical energy when stretched, yarns that store this electrical energy, and textile geometries that facilitate these functions. To address these challenges, this research incorporates highly stretchable electrochemical yarn harvesters, where available mechanical strains are large and electrochemical energy storing yarns are achieved by weaving. The solid‐state yarn harvester provides a peak power of 5.3 W kg^?1 for carbon nanotubes. The solid‐state yarn supercapacitor provides stable performance when dynamically deformed by bending and stretching, for example. A textile configuration that consists of harvesters, supercapacitors, and a Schottky diode is produced and stores as much electrical energy as is needed by a serial or parallel connection of the harvesters or supercapacitors. This textile can be applied as a power source for health care devices or other wearable devices and be self‐powered sensors for detecting human motion.     

"How interchangeable are different estimators of effect size?": Correction to Ray and Shadish (1996).

Reports an error in the original article by J. W. Ray and W. R. Shadish (Journal of Consulting and Clinical Psychology, 1996[Dec], Vol 64(6), 1316–1325). On page 1325, a correction is made to column 1, lines 25–26. (The following abstract of this article originally appeared in record 1996-07086-021). The computation of effect sizes is a key feature of meta-analysis. In treatment outcome meta-analyses, the standardized mean difference statistic on posttest scores (d) is usually the effect size statistic used. However, when primary studies do not report the statistics needed to compute d, many methods for estimating d from other data have been developed. Little is known about the accuracy of these estimates, yet meta-analysts frequently use them on the assumption that they are estimating the same population parameter as d. This study investigates that assumption empirically. On a sample of 140 psychosocial treatment or prevention studies from a variety of areas, the present study shows that these estimates yield results that are often not equivalent to d in either mean or variance. The frequent mixing of d and other estimates of d in past meta-analyses, therefore, may have led to biased effect size estimates and inaccurate significance tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory effect in a junction-like CdS nanocomposite/conducting polymer poly[2-methoxy-5-(2-ethylhexyloxy)1,4-phenylene-vinylene] heterostructure

The operation of a nonvolatile memory device is demonstrated using junction-like CdS nanocomposites embedded in a polymer matrix. The capacitance-voltage characteristics of Al/conducting polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene-vinylene]/CdS nanocomposites in a polyvinyl alcohol matrix/indium tin oxide device exhibit hysteresis, which is attributed to the trapping, storage, and emission of holes in the quantized valence band energy levels of isolated CdS nanoneedles. The characteristics at different operating frequencies show that the hysteresis is due to trapping of charge carriers in CdS nanocomposites rather than in the interfacial states. The memory behavior in the inorganic/organic heterostructure is explained on the basis of a simple energy band diagram.     

Modified Trident UWB Printed Monopole Antenna

Wireless Personal Communications - A new modified trident printed monopole configuration for Ultra wideband applications is presented. This monopole antenna has multi resonant segments of...     

Wide Bandgap Phase Change Material Tuned Visible Photonics

Light strongly interacts with structures that are of a similar scale to its wavelength, typically nanoscale features for light in the visible spectrum. However, the optical response of these nanostructures is usually fixed during the fabrication. Phase change materials offer a way to tune the properties of these structures in nanoseconds. Until now, phase change active photonics has used materials that strongly absorb visible light, which limits their application in the visible spectrum. In contrast, Sb₂S₃ is an underexplored phase change material with a bandgap that can be tuned in the visible spectrum from 2.0 to 1.7 eV. This tuneable bandgap is deliberately coupled to an optical resonator such that it responds dramatically in the visible spectrum to Sb₂S₃ reversible structural phase transitions. It is shown that this optical response can be triggered both optically and electrically. High‐speed reprogrammable Sb₂S₃ based photonic devices, such as those reported here, are likely to have wide applications in future intelligent photonic systems, holographic displays, and microspectrometers.     

MSXmin: a modular multicast ATM packet switch with low delay andhardware complexity

We propose and analyze the architecture for a large-scale high-speed multicast switch called MSXmin. The hardware complexity of MSXmin is O(N log² N) which compares favorably with existing architectures. Further, the internal latency of the MSXmin is O(log² N) bits. While it is superior to the existing architectures in terms of the hardware complexity and the internal latency, it is comparable to other multicast switches in terms of the header overhead and translation table complexity. MSXmin is output buffered and based on the group knockout principle. Moreover, MSXmin is a dual-bit-controlled tree-based switch     

Optimal supervisory control of finite state automata

This paper presents optimal supervisory control of dynamical systems that can be represented by deterministic finite state automaton (DFSA) models. The performance index for the optimal policy is obtained by combining a measure of the supervised plant language with (possible) penalty on disabling of controllable events. The signed real measure quantifies the behaviour of controlled sublanguages based on a state transition cost matrix and a characteristic vector as reported in earlier publications. Synthesis of the optimal control policy requires at most n iterations, where n is the number of states of the DFSA model generated from the unsupervised plant language. The computational complexity of the optimal control synthesis is polynomial in n. Syntheses of the control algorithms are illustrated with two application examples.     

Influence of untreated and novel electron‐beam‐modified surface‐coated silica filler on the thermorheological properties of ethylene–octene copolymer

We developed surface‐modified silica fillers by coating these with an acrylate monomer, trimethylolpropane triacrylate, or a silane coupling agent, triethoxyvinyl silane, followed by electron‐beam irradiation at room temperature. These were incorporated in an ethylene–octene copolymer rubber. Thermorheological studies of the unvulcanized ethylene–octene copolymer and its untreated and modified silica‐filled composites were done with a shear dynamic oscillating rheometer. Modification of the silica filler, especially via the silanization process followed by electron beam treatment, significantly reduced filler–filler networking as revealed from the log–log plots of storage modulus and complex shear viscosity, and its real component. The rheological complexity of the compositions was analyzed from a double logarithmic plot of the storage modulus and loss modulus. The results obtained from the master curves constructed on the basis of the time–temperature superposition principle and the activation energy calculated from the Arrhenius equation for the flow of above these compounds further supported these findings. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2453–2459, 2003