W* effect considered harmful [Internet WAP]

Claiming that “wireless is different” WAP 1.1 rewrites almost every Web standard in the book. The commercial demand for WAP has proved sufficient to implement most of its technologies, but it should be adopted very cautiously. The author discusses the component technologies of WAP     

Impact of ozonation on subsequent treatment of azo dye solutions

BACKGROUND: Aqueous solutions of four azo‐dyes, Acid Red 14 (AR14), Congo Red (CR), Reactive Black 5 (RB5), and Reactive Violet 5 (RV5) were treated with ozone, and the impact of ozonation on their subsequent treatability by aerobic biodegradation processes was investigated. RESULTS: In all cases, ozonation at the highest ozone doses investigated could remove more than 96% of the original dye, and the corresponding residual colour of the azo dye solutions declined to less than 20 on the Pt‐Co scale. Ozonation also resulted in reduction of chemical oxygen demand (COD), total organic carbon (TOC) the COD/TOC ratio and pH, while in all cases electrical conductivity of the dye solutions increased. Activity of the microbial colonies present in domestic wastewater was not inhibited when un‐ozonized solutions of these dyes were mixed in a 1:1 volumetric ratio with domestic wastewater, although the dyes themselves were not degraded. Also, no significant inhibition of microbial activity was observed in 1:1 mixtures of ozonized dye solutions and domestic wastewater, especially when the initial dye concentration was low and the applied ozone dose was high. In almost all cases, progressively enhanced BOD exertion was observed in mixtures containing dye solutions ozonized with progressively higher doses. This indicated that some ozonation by‐products of the above dyes could be degraded by microorganisms present in domestic wastewater. CONCLUSIONS: It was concluded that the above dye solutions, after ozonation for partial or complete colour removal, could be mixed with domestic wastewater for subsequent treatment by aerobic biological processes, with no adverse impact on the activity of the microbial colonies present in domestic wastewater. Copyright © 2007 Society of Chemical Industry     

Automatic System for Measuring and Controlling the Length of a Moving Product in Industries

This paper describes the design and development of a very simple low-cost online system for measuring the length of moving billets in the steel industry. Few photosensors, digital logic gates, and light-emitting diodes are used to track and display the wide variation in billet length. Not a single amplifier or comparator is used in photosensor circuit. The comparative study shows its superiority over other costly dimension-measuring systems, viz., shaft encoder, laser Doppler meter, and charge-coupled-device camera. Before, an operator had a risk of an accident while crossing the hot-cobble-prone area for measuring the billet length. However, today, the length of each billet is displayed in a pulpit, thereby increasing the safety. The measuring error in the billet length, ranging from +100 to -100 mm, is reduced to +50 mm. The fluctuation in linear velocity of an incoming billet to a flying shear causes wide variation in its cut lengths. To overcome this severe problem, the speed of the flying shear is adjusted during the tail end of each billet. The benefit of the system is in the tune of Rs 49.5 times 10⁶ (approximately U.S. $1.26 times 10⁶) per annum, whereas the payback period is less than 15 days. Apart from the different steel products like the slab, bloom, and rail, the developed system is also useful in the dimensional measurement of the products in nonferrous industries.     

Anatomy of a URL (and other Internet-scale namespaces. 1)

The author discusses the anatomy of a URL (Uniform Resource Locator). He considers domain names, IP addresses, MAC addresses, phone numbers, path names and names in HTTP messages     

A Room‐Temperature Ferroelectric Ferromagnet in a 1D Tetrahedral Chain Network

Ferroelectricity occurs in crystals with broken spatial inversion symmetry. In conventional perovskite oxides, concerted ionic displacements within a 3D network of transition‐metal–oxygen polyhedra (MO_x) manifest spontaneous polarization. Meanwhile, some 2D networks of MO_x foster geometric ferroelectricity with magnetism, owing to the distortion of the polyhedra. Because of the fundamentally different mechanism of ferroelectricity in a 2D network, one can further challenge an uncharted mechanism of ferroelectricity in a 1D channel of MO_x and estimate its feasibility. Here, ferroelectricity and coupled ferromagnetism in a 1D FeO₄ tetrahedral chain network of a brownmillerite SrFeO_2.5 epitaxial thin film are presented. The result provides a new paradigm for designing low‐dimensional MO_x networks, which is expected to benefit the realization of macroscopic ferro‐ordering materials including ferroelectric ferromagnets.     

Highly dispersible and uniform size Cu2ZnSnS4 nanoparticles for photocatalytic application

Highly dispersible, uniform size (～7 nm) single-phase Cu₂ZnSnS₄ nanoparticles have been synthesized by hydrothermal method using non-toxic surfactant (oleic acid). High resolution transmission electron microscopy image indicates good crystallinity of the Cu₂ZnSnS₄ nanoparticles with the growth along (1 1 2) plane. X-ray photoelectron spectroscopy analyses suggested that the formation of with Cu, Zn, and Sn in +1, +2 and +4 oxidation states. The optical absorption spectrum of Cu₂ZnSnS₄ nanoparticles exhibits an absorption in the visible region and its optical band gap was found to be ～1.72 eV, which could be much more appropriate for photocatalytic application under visible light irradiation. These Cu₂ZnSnS₄ nanoparticles have been shown high photocatalytic degradation activity of methylene blue (MB) dye in the presence of visible light irradiation. The rate constant (k) value of Cu₂ZnSnS₄ nanoparticles is found to be 0.0144 min^?1. We have discussed the mechanism of dye degradation process that drives the photocatalytic degradation process. The reusability of the Cu₂ZnSnS₄ nanoparticles for the dye degradation is also demonstrated.     

Utilization of the Yellow Component of a Copper-Vapor Laser for Extending the Tuning Range of a Rhodamine 6G Dye Laser by Use of an Additional Dye in a Novel Coupled Resonator Scheme

We demonstrate the use of both 510.6- and 578.2-nm components and the extension of the tuning range of a Rhodamine 6G dye laser in a novel coupled resonator scheme. Rhodamine 6G is pumped by 510.6-nm light in one resonator and Sulforhodamine B is pumped by 578.2 nm in the other. The spectral tuning range of 564-609 nm of the Rhodamine 6G laser is extended up to 640 nm. A two-mirror arrangement ensures continuous tuning across the spectral ranges of the two dyes by rotation of a single plane mirror.     

The transfer protocols

There are many Internet-scale messaging systems: Telnet for duplex byte streams, File Transfer Protocol (FTP) for pulling files, Simple Mail Transfer Protocol (SMTP) for reliable e-mail messaging, Network News Transfer Protocol (NNTP) for pushing e-mail, HyperText Transfer Protocol (HTTP) for pulling Web pages, and a host of other special-purpose schemes, from Finger to Network File System (NFS). How can we make sense of it all? Understanding the history of these transfer protocols (TPs) is the key to charting their future, especially as new contenders like HTTP-NG (next-generation) emerge. In this article, I set forth a general ontology-a vocabulary for describing and classifying TPs, with the aim of developing a framework to help navigate among the alternatives     

Detection of collision using optimized deep model and mitigation of collision using dolphin ant lion optimizer in wireless sensor network

Wireless sensor network (WSN) comprises automatic sensors that are dispersed into a huge region. WSN is constructed from huge sensors, which is allocated to a particular task and the majority of task involves reporting and monitoring. However, as the network can be extended to several sensor nodes, there is a high chance of collision. Thus, this paper devises a novel technique for performing both collision detection and mitigation in WSN. Initially, the simulation of WSN is performed, and then the selection of cluster head is done using fractional artificial bee colony (FABC). Here, the network-based parameter is extracted that involves received signal strength index (RSSI), priority level, delivery rate, and energy consumed. The deep recurrent neural network (DRNN) is adapted for collision detection. Here, the training of DRNN is done using lion crow search optimizer (LCSO). After collision detection, the collision mitigation is performed with a pre-scheduling algorithm, namely dolphin ant lion optimizer (Dolphin ALO). Here, fitness is considered for collision mitigation that includes energy, sleep index (SI), delivery rate, priority level, E-waste, and E-save. The proposed method outperformed with the smallest energy consumption of 0.185, highest throughput of 0.815, highest packet delivery ratio (PDR) of 0.815, and highest collision detection rate of 0.930.     

Free vibration of composite and sandwich laminates with a higher-order facet shell element

A simple C⁰ isoparametric finite element formulation based on a shear deformable model of higher-order theory using a higher-order facet shell element is presented for the free vibration analysis of isotropic, orthotropic and layered anisotropic composite and sandwich laminates. This theory incorporates a realistic non-linear variation of displacements through the shell thickness, and eliminates the use of shear correction coefficients. The validity and efficiency of the present formulation is established by obtaining solutions to a wide range of problems and comparing them with the available three-dimensional closed-form and finite element solutions. In addition, other plate and shell solutions of different kind and available in the literature are also compiled and tabulated for the sake of completeness. The parametric effects of degree of orthotropy, length-to-thickness ratio, plate aspect ratio, number of layers and fibre orientation upon the frequencies and mode shapes are discussed.