Human activity recognition by combining external features with accelerometer sensor data using deep learning network model

Multimedia Tools and Applications - Various Human Activities are classified through time-series data generated by the sensors of wearable devices. Many real-time scenarios such as Healthcare...     

A KINETIC APPROACH TO EVALUATE THE ENERGY AND ENTROPY OF ACTIVATION FOR THE EXCHANGE OF ALKALINE EARTH METAL IONS ON TIN(IV) TUNGSTATE CATION EXCHANGER

Abstract

A new approach based on the Nernst-Planck equations has been applied to study the reaction kinetics on the surface of tin(IV) tungstate for the Mg(II)-H(I), Ca(II)-H(I), Sr(II)-H(I) and Ba(IT)-H(I) exchanges under the conditions favouring a particle diffusion phenomenon. On the basis of these studies the various physical parameters such as the effective diffusion coefficients, activation energies and entropies of activation have been evaluated which give some informations regarding the mechanism of ion-exchange on the surface of inorganic materials.     

Thermal interface tailoring in composite materials

The thermal transport in heterogeneous materials systems, such as in composites, is essentially controlled by the phonon scattering phenomena at the materials interface due to the interface materials property mismatch. Such phenomena are also prevalent in joints or component interfaces. The thermal property mismatch at the materials interface, in the molecular scale, is primarily dictated by the phonon density of state across the interface. In this paper, the interface materials configuration for tailoring the thermal properties of composite materials with nano constituents is presented. The materials modeling using both the finite element analysis (FEM) and molecular dynamics (MD) simulations is performed to identify the effect of materials constituent scale as well as the nano constituent surface functionalization on the interface thermal transport phenomena. It is observed that the effect of surface functionalization towards establishing covalent bonding between the nano constituent surface the matrix (such as polymers) is extremely important in enhancing the interface thermal conductance.     

Growth and field emission study of a monolithic carbon nanotube/diamond composite

Carbon nanotube (CNT)/diamond composite has been fabricated by hot filament chemical vapor deposition on a silicon substrate using iron as catalyst. The material characteristics of this monolithic structure were examined by electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and electron energy loss spectroscopy. The composite material shows the presence of carbon nanotubes of several microns in length together with conspicuous diamond microcrystals of sizes ranging from 0.5 to 2.0 μm. The CNTs protrude from the diamond microcrystals and become entangled around them as they grow. This monolithic CNT/diamond composite provides an intrinsic heat dissipation mechanism for CNTs during field emission and exhibits low turn on field, large field enhancement factor, and an excellent current stability over a period of 44 h.     

Connection Rerouting for Wireless ATM Networks

Wireless ATM (Asynchronous Transfer Mode) is an emerging technology designed to provide multimedia and other Quality of Service-oriented applications to mobile users by extending ATM connections to involve wireless links. The use of wireless ATM has also been motivated by an increasing deployment of ATM technology in backbone networks and also due to the need to support emerging services in the next generation (broadband) wireless networks, both terrestrial and satellite based. Since ATM was originally designed for high bandwidth and low error rate environment to support stationary users, the use of ATM in wireless environment raises many interesting issues. These include managing end-to-end ATM connection (using connection re-routing), maintaining location information about users as they move, supporting transmission of ATM cells over wireless links, and supporting quality of service )QoS( requirements in limited bandwidth environment. As users move, the end-to-end ATM connections need to be rerouted to support continued communications. The design of such rerouting schemes has recently received some consideration in literature, however many important issues including support for multicast and overhead requirements have not been fully addressed. In this paper, we present a detailed treatment of connection rerouting issues, design and performance evaluation of two rerouting schemes, and the support for multicast rerouting.     

Tungsten carbide,boron carbide,and MWCNT reinforced poly(aryl ether ketone) nanocomposites: Morphology and thermomechanical behavior

This study involves the development and thermo-mechanical characterization of the individual, binary, and ternary nanocomposites using radiation resistant fillers like boron carbide (B₄C), tungsten carbide (WC), and functionalized multi-walled carbon nanotubes (F-MWCNT) in a high performance polymer, namely, poly aryl ether ketone (PAEK). Transmission electron microscopy studies revealed the distribution and dispersion of nanofillers in the matrix. It has been observed that the presence of WC and F-MWCNT in PAEK matrix significantly enhanced the tensile strength of the composite whereas B₄C made it stiff and brittle in nature. The tensile property improvement caused by WC and F-MWCNT has been correlated with the tensile fracture surface morphology studies. Dynamic mechanical analysis provided insight into the positive effect of nanofillers in delaying the relaxation of polymer chains. The thermogravimetric analysis gave indications on the increase in the thermal stability of the nanocomposites with the increase of nanofillers content. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47032.     

Imaging for concealed weapon detection: a tutorial overview of development in imaging sensors and processing

Manual screening procedures for detecting concealed weapons such as handguns, knives, and explosives are common in controlled access settings like airports, entrances to sensitive buildings, and public events. The detection of weapons concealed underneath a person's clothing is an important obstacle to the improvement of the security of the general public as well as the safety of public assets like airports and buildings. It is desirable to be able to detect concealed weapons from a standoff distance, especially when it is impossible to arrange the flow of people through a controlled procedure. The goal is the eventual deployment of automatic detection and recognition of concealed weapons. It is a technological challenge that requires innovative solutions in sensor technologies and image processing. A number of sensors based on different phenomenology as well as image processing support are being developed to observe objects underneath people's clothing. The main aim of this article is to provide a tutorial overview of these developments.     

Study of electrical conductivity changes and phase transitions in TiO2 doped ZrO2

The electrical conductivity in ZrO₂ doped with various molar ratios of TiO₂ has been measured at different temperatures. Phase transitions depending on the temperature for different molar compositions were investigated by doping of the samples. The conductivity is also found to increase with rise in temperature till 200 °C and thereafter decreases due to collapse of the fluorite framework. A second rise in conductivity in the doped samples around 462 °C is observed due to phase transition of ZrO₂. X-ray powder diffraction recorded at high temperature show the effect of doping and the phase relationships of doped materials. DTA was also carried out for confirming doping effect and phase transition in samples.     

Effects of Ionizing Radiation on Microbial Decontamination, Phenolic Contents, and Antioxidant Properties of Triphala

ABSTRACT:  Triphala, a mixture of Emblica officinalis , Terminalia chebula , and Terminalia bellirica , containing ingredients from plant origin, is often prone to microbial contamination. A high level of microbial contamination was observed in Triphala samples obtained from different sources. On gamma radiation processing, a sharp decline in log CFU was observed with increasing radiation dose and a complete decontamination at 5 kGy. Average D 10 value for total aerobic and fungal counts were observed to be 0.55 ± 0.073 kGy and 0.94 ± 0.043 kGy, respectively. Water extracts of irradiated samples showed linearly increasing concentration of gallic acid (3.3 to 4.5 times), total phenolic contents (2.16 to 2.87 times), and antioxidant properties with increasing radiation dose up to 25 kGy. The increase could be attributed to easy release of active ingredients from their radiation degraded complex forms. Aflatoxin B₁ and ochratoxin could not be detected in the samples. Gamma-radiation dose up to 5 kGy could be safely used to hygienize Triphala.