Proposal for Highly Nonlinear Dispersion-Flattened Octagonal Photonic Crystal Fibers

A highly nonlinear photonic crystal fiber (HNL-PCF) based on an octagonal structure with isosceles triangular-latticed cladding is proposed for the telecommunication window. The finite-difference method with anisotropic perfectly matched boundary layer is used to investigate the guiding properties. It is demonstrated that it is possible to design a simple HNL low-loss dispersion-flattened PCF with a nonlinear coefficient of the order 27 W^-1km^-1 at a 1.55-mum wavelength. According to simulation, ultraflattened dispersion of 0 plusmn 0.5 ps/nm/km is obtained in a 1.46- to 1.66-mum wavelength with low confinement losses less than 0.06 dB/km in the entire band of interest.     

Link failure and congestion-aware reliable data delivery mechanism for mobile ad hoc networks

Link failures and packet drops due to congestion are two frequently occurring problems in mobile ad hoc networks, degrading the network performance significantly. In this paper, we propose a link failure and congestion-aware reliable data delivery (LCRDD) mechanism that jointly exploits local packet buffering and multilevel congestion detection and control approaches for increasing the data delivery performance. On the detection of link failure or congestive state, an LCRDD intermediate node buffers the incoming data packets at the transport layer queue and resumes transmission when the route is repaired locally. In addition, LCRDD’s multilevel congestion detection helps it to take the most appropriate action proactively. Thus, it offers increased reliability and throughput and decreased end-to-end packet delivery delay and routing overhead compared to state-of-the-art protocols, as shown in results of performance evaluations carried out in network simulator v-2.34.     

Topology based placement of multicast capable nodes for supporting efficient multicast communication in WDM optical networks

Most existing algorithms for the problem of optical signal splitter placement or multicast splitting-capable node placement in a WDM network are based on the performance of attempting a large set of randomly generated multicast sessions in the network. Experiments show that placement of multicast capable nodes based on their importance for routing one set of multicast sessions may not be a right choice for another set of multicast sessions. In this work, we propose placement algorithms that are based on network topology and the relative importance of a node in routing multicast sessions, which is measured by our proposed metrics. Since a network topology is fixed once given, the proposed algorithms are essentially network traffic independent. We evaluate the proposed placement algorithms given static sets of multicast sessions as well as under dynamic traffic conditions, which are routed using our splitter constrained multicast routing algorithm. Our results show that the proposed algorithms perform better, compared to existing algorithms.     

Green biocides,a promising technology: current and future applications to industry and industrial processes

The study of biofilms has skyrocketed in recent years due to increased awareness of the pervasiveness and impact of biofilms. It costs the USA literally billions of dollars every year in energy losses, equipment damage, product contamination and medical infections. But biofilms also offer huge potential for cleaning up hazardous waste sites, filtering municipal and industrial water and wastewater, and forming biobarriers to protect soil and groundwater from contamination. The complexity of biofilm activity and behavior requires research contributions from many disciplines such as biochemistry, engineering, mathematics and microbiology. The aim of this review is to provide a comprehensive analysis of emerging novel antimicrobial techniques, including those using myriad organic and inorganic products as well as genetic engineering techniques, the use of coordination complex molecules, composite materials and antimicrobial peptides and the use of lasers as such or their modified use in combination treatments. This review also addresses advanced and recent modifications, including methodological changes, and biocide efficacy enhancing strategies. This review will provide future planners of biofilm control technologies with a broad understanding and perspective on the use of biocides in the field of green developments for a sustainable future. © 2013 Society of Chemical Industry     

Development of functional alginate fibers for medical applications

In this study, antibacterial alginate fibers were developed by using two approaches for fiber development. Firstly, replacing the sodium ions of sodium alginates with metal ions like zinc. Secondly, replacing the sodium ions of sodium alginate with biologically inactive ions like calcium and loading the fibers with ZnO nanorods. Fibers were characterized by liquid absorption and ion release measurements, by placing them separately in distilled water, solution A (0.8298% NaCl & 0.0368% CaCl2) and normal saline solution. Results showed that release of ions from fibers was affected by liquid absorption, physiology of solution and contact time with solution. More ions were released from fibers with higher absorption and longer contact time. Calcium alginate fibers containing zinc ions showed greater absorbency as well as the greater metal ions release. Fibers containing zinc ions, and ZnO nanorods were also tested for their mechanical properties and antibacterial properties against Staphylococcus aureus and Escherichia coli. Alginate fibers containing ZnO nanorods were stronger than alginate fibers containing zinc ions. However, calcium fibers containing zinc ions exhibited more antibacterial activity.     

The effects of ordering on the morphology of two-layer alumite—Forming a patterned interface

Two-layer alumite has been synthesized by three-step anodizing such that the 1st layer was formed by commonly known two-step anodizing at a prescribed voltage and the 2nd layer was formed at two-times higher anodizing voltage, in suitable electrolytes. When the 2nd layer is formed at an ordering voltage, alternate pores of the 1st layer continue growing through the 2nd layer, in a regular pattern. The neighboring pores cease their growth, possibly due to upward flow and thickening of barrier oxide at the new cell boundaries. The growing pores in the 2nd layer are equi-distant provided that the 1st layer is also formed under ordering conditions. If the 2nd layer is formed under non-ordering conditions the regular pattern at the interface is completely lost. Employing the two-layer alumite, nanowires by the 1st layer can be grown such that alternate pores remain empty, providing a new superlattice.     

Simulating oriental brush character considered with aerial action of pen tablet

Multimedia Tools and Applications - The calligraphy is widely known in the oriental countries and has received art and high evaluation in history. The calligraphy is not only intended as a means of...