Cubic–Quartic Optical Solitons with Differential Group Delay for Kudryashov’s Model by Extended Trial Function

Journal of Communications Technology and Electronics - This paper implements mathematically rigorous extended trial function algorithm to address cubic–quartic optical solitons in...     

Azeotrope formation in gasoline–ethanol blends. Part 1 – Impact of nonionic on E10 distillation curve

Blending 10?vol% of ethanol into hydrocarbon base gasoline (HBG) increases significantly the vapour pressure of the blend (E10), and exhibits near-azeotrope behaviour that severely affects the shape of E10 distillation curve. The distillation curves of HBG and E10 fuel blend, were constructed using ASTM D86 distillation data, and the areas under each distillation curve, were calculated through the numerical trapezoid rule (NTR) and calculus definite integration (CDI) methods. Consequently, the area due to azeotrope formation (ADAF), was estimated. In this paper, we present the impact of small concentration of nonionic surfactant on the area under distillation curve (AUDC) of E10 fuel blend and the area due to azeotrope formation (ADAF). Also, the influences of the added surfactant on the volatility criteria of the investigated E10 fuel blend were discussed.     

Time-variant balanced routing strategy for underwater wireless sensor networks

In the past decade, researchers’ interest in Underwater Wireless Sensors Networks has rapidly increased. There are several challenges facing the lifetime of UWSNs due to the harsh characteristics of the underwater environment. Energy efficiency is one of the major challenges in UWSNs due to the limited battery budget of the sensor nodes. In this paper, we aim at tackling the energy sink-hole problem that especially hits nodes close to the sink when they run out of battery power before other sensors in the network. We prove that we can evenly distribute the transmission load among mobile sensor nodes by letting sensor nodes adjust their transmission ranges. In this paper, we suppose that sensor nodes may adjust their transmission power up to three levels. Consequently, we strive for deriving the optimal load weight for each possible transmission power level that leads to fair energy consumption among all underwater sensors while taking into account the underwater sensors mobility. Performance results show that energy sink-hole problem is overcame and hence the network lifetime is maximized.

     

A modified rain attenuation prediction model for tropical V‐band satellite earth link

Radio wave propagation plays a very important part in the design and eventually dictates performance of space communication systems. Over time, the requirements of satellite communication have grown extensively where higher capacity communications systems are needed. Escalating demands of microwave and millimetre wave communications are causing frequency spectrum congestion. Hence, existing and future satellite system operators are planning to employ frequency bands well above 10 GHz. The challenge in operating at such high frequencies for communication purposes is that there exists stronger electromagnetic interaction between the radio signals and atmospheric hydrometeors. Such instances will degrade the performance of such high frequency satellite communication systems. The development of a revised model for a better‐improved rain fade prediction of signal propagations in tropical region is considered very important. Researchers and engineers can employ the model to accurately plan the future high frequencies satellite services. Copyright © 2014 John Wiley & Sons, Ltd.     

Interference Aware Route Discovery in Wireless Mobile Ad Hoc Networks

In this paper, we propose an interference aware expanding region search algorithm to locate a destination in mobile ad hoc networks. In the proposed approach, signal to interference plus noise ration (SINR) is used in place of TTL field of a route request packet. The source node initializes the search query with a threshold value of SINR. Each relay node forwards the packet if its SINR satisfies the threshold criteria provided by the source node in RREQ packet. As a result, the low SINR nodes are removed in route discovery phase prior to the establishment of routes. The simulation results show that proposed algorithm provides significant improvement in performance of reactive routing protocol in terms of reduced routing overhead, reduced energy consumption, and increased network throughput.

     

Quantum‐Tunneling Metal‐Insulator‐Metal Diodes Made by Rapid Atmospheric Pressure Chemical Vapor Deposition

A quantum‐tunneling metal‐insulator‐metal (MIM) diode is fabricated by atmospheric pressure chemical vapor deposition (AP‐CVD) for the first time. This scalable method is used to produce MIM diodes with high‐quality, pinhole‐free Al₂O₃ films more rapidly than by conventional vacuum‐based approaches. This work demonstrates that clean room fabrication is not a prerequisite for quantum‐enabled devices. In fact, the MIM diodes fabricated by AP‐CVD show a lower effective barrier height (2.20 eV) at the electrode–insulator interface than those fabricated by conventional plasma‐enhanced atomic layer deposition (2.80 eV), resulting in a lower turn on voltage of 1.4 V, lower zero‐bias resistance, and better asymmetry of 107.     

A probabilistic home-based routing scheme for delay tolerant networks

Wireless Networks - In traditional Mobile Adhoc Networks routing algorithms, the existence of a sustainable path between the source and destination is a crucial issue. These algorithms are shown to...     

Design and Implementation of Optical Signal Reinstatement Technique for High DPSK RZ Transceiver Scheme

Wireless Personal Communications - Optical signal reinstatement (OSR) is a common technique used in high-speed communication systems. OSR can be achieved using various techniques such as;...     

A CMOS digitally programmable filter technique for VLSI applications

A novel technique for designing analog CMOS integrated filters is proposed. The technique uses digitally controlled current amplifiers (DCCAs) to provide precise frequency and/or gain characteristics that can be digitally tuned over a wide range. This paper provides an overview of the possibilities of using the DCCA as the core element in programmable filters. In mixed analog/digital systems, the digital tuning feature of the proposed approach allows direct interfacing with the digital signal processing (DSP) part. Basic building blocks such as digitally programmable amplifiers, integrators, and simulated active inductors are given. Systematic designs of second-order filters are presented. Fully differential architectures of the proposed circuits are developed. Experimental results obtained from 0.5 μm standard CMOS chips are provided.