A forward fast media independent handover control scheme for Proxy Mobile IPv6 (FFMIH-PMIPv6) over heterogeneous wireless mobile network

Proxy Mobile IPv6 (PMIPv6) is a networked-based handover protocol for the IP layer, i.e., the layer 3 mobility management protocol. In this work, we integrate fast handover and IEEE 802.21 Media Independent Handover (MIH) Services with PMIPv6 to improve the handover performance over the heterogeneous wireless network environment. Since it may have multiple candidate destination networks to which a Mobile Node can select for handover, it needs to consider not only the signal strength but also the corresponding networking situation for the proper selection of the next network. To reduce the packet loss situation, the multicast mechanism is adopted to forward packets to these candidate destination networks during the handover processing period. In this work, a Forward Fast Media Independent Handover Control Scheme for Proxy Mobile IPv6 (FFMIH-PMIPv6) is proposed based on the aforementioned concerns. Through the simulations for performance analysis, it shows that the proposed FFMIH-PMIPv6 can have better handover performance in terms of handover latency, packet loss rate and throughput.     

Pulmonary melioidosis

Melioidosis is the name given to all diseases caused by the bacterium Pseudomonas pseudomallei. Melioidosis is a tropical disease and prevails in parts of Southeast Asia, northern Australia, and Central and South America. However, in recent years, cases of melioidosis have been reported in the United States and other areas. The organism can infect any organ system, although the lung is the most common organ affected. Pulmonary melioidosis presents either as an acute fulminant pneumonia or as an indolent cavitary disease. In northeastern Thailand, the incidence of P pseudomallei infection is extremely high with significant mortality. One of the key problems with treating melioidosis is its recalcitrance to therapy and high relapse rate. In addition, this Gram-negative rod is resistant to aminoglycosides. In nonendemic regions, patients with melioidosis more typically present with reactivation disease occurring months to years after initial exposure to the organism. The pulmonary disease is mainly in the apices and resembles tuberculosis. With the increasing mobility of people throughout the world and the influx of immigrants from endemic to nonendemic areas, it is important that clinicians be aware of this disease. This article will review the epidemiology, clinical presentations, diagnosis, and treatment of pulmonary melioidosis.     

Clarification of viscous poly tetramethylene ether glycol (PTMEG) containing solid suspension by dead‐end flow microfiltration under constant pressure

In this study, the microfiltration of polyester fluid containing solid suspension has been investigated under constant pressure. A membrane module, which consists of a microfilter paper of surface area of 19.4 cm² and a SS‐316 net support (160 mesh), was used. It was found that the homogeneous sodium acetate suspension in polymer can be completely removed by the membrane filter paper to yield a very clear polymer product. The property and rheology of polyester fluid with suspending solids have been studied. The polymer fluid can be viewed as a Newtonian fluid in this work. The filtration behavior in the membrane system was simulated by the blocking filtration law. Satisfactory fit between experimental data and theoretical calculations was demonstrated. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2303–2312, 1999     

The effect of surface chemistry in lubrication on the tribological behaviour of steel rollers under rolling-sliding contacts

Experiments were carried out on a wear test machine utilising a gearcam adapter to simulate line-contact lubrication. Due to the formation of a surface adsorption layer on the steel substrate, the tribological performance was detected by measuring the voltage for a lubricant with various additive concentrations. The roller wear rate was found to be strongly dependent upon both the rising rate of voltage in the wear process and the time period needed to create a positive voltage. The antiwear effect of differing additive concentrations was evaluated using the measurements of voltage for various operating conditions. An increase in rotational speed, with a lubricating oil with a low additive concentration, decreases the wear rate. A lubricating oil with a high additive concentration does little to decrease the wear rate at low rotational speeds.     

Fast approach for H.264 inter mode decision

A fast inter mode decision approach for H.264 coding standard is presented. The objective is to reduce the number of candidate block types in motion estimation. Experimental results show that the proposed method can efficiently save the computation cost for inter mode decision while maintaining the same PSNR and bit rate.     

The Safe Operating Area of GaAs-Based Heterojunction Bipolar Transistors

The safe operating area (SOA) of GaAs-based heterojunction bipolar transistors has been studied considering both the self-heating effect and the breakdown effect. The Kirk effect induced breakdown (KIB) was considered to account for the decrease of the breakdown voltage at high currents. With reasonable emitter ballastors, the KIB effect was shown to be the major cause for device failure at high currents, while the thermal effect controls the low current failure. The effect of emitter resistance and base resistance on device stability was also studied. While the emitter resistance always improves the device stability by expanding the SOAs, the base resistance degrades SOAs when the KIB dominates the failure mechanism. The effect of the base resistance on SOAs was explained by its control on the flow of the avalanche current. Since the KIB effect depends on the collector structure, it was shown that a nonuniformly doped collector can effectively improve the SOAs     

General switch‐and‐examine relaying for demodulate‐and‐forward cooperative diversity

Two new demodulate‐and‐forward schemes of multi‐relay cooperative diversity with switch‐and‐examine relaying (SER) are analyzed. To reduce relay usage and enhance bandwidth efficiency, the two new cooperative diversity schemes employ a switch‐based relay selection. The proposed schemes consume less communication resource than regular relaying schemes, such as the selection combining (SC) or maximal ratio combining (MRC) schemes that always use all relays, and also achieve better performance than distributed switch‐and‐stay schemes. In the first scheme, the decision statistic for relay usage and selection is based on the signal‐to‐noise ratio (SNR). In the second scheme, the log‐likelihood ratio (LLR) of received signals is used for the decision of relay usage and selection. With the two SER schemes, the bit error probability (BEP) of binary phase shift keying (BPSK) and the average number of used paths are derived and expressed in closed‐form for the independent and identically distributed (i.i.d.) Rayleigh fading channels. Numerical and simulation results are presented for performance illustrations. According to the numerical results, the LLR‐based SER not only achieves a lower BEP but also consumes less relay resource than the SNR‐based SER. Furthermore, the LLR‐based SER scheme even outperforms the corresponding SNR‐based SC scheme for a range of average SNR. Copyright © 2014 John Wiley & Sons, Ltd.