Electronic transport behavior of 4,6-bis(4-nitrophenyl)-2-phenyl-3,5-diaza-bicyclo[3.1.0]hex-2-ene (a bicyclic aziridine) as optical molecular switch: a first-principles approach

Journal of Computational Electronics - In this study, the electronic transport properties of 4,6-bis(4-nitrophenyl)-2-phenyl-3,5-diaza-bicyclo[3.1.0]hex-2-ene (as a bicyclic aziridine) have been...     

Application of artificial intelligence to improve quality of service in computer networks

Resource sharing between book-ahead (BA) and instantaneous request (IR) reservation often results in high preemption rates for ongoing IR calls in computer networks. High IR call preemption rates cause interruptions to service continuity, which is considered detrimental in a QoS-enabled network. A number of call admission control models have been proposed in the literature to reduce preemption rates for ongoing IR calls. Many of these models use a tuning parameter to achieve certain level of preemption rate. This paper presents an artificial neural network (ANN) model to dynamically control the preemption rate of ongoing calls in a QoS-enabled network. The model maps network traffic parameters and desired operating preemption rate by network operator providing the best for the network under consideration into appropriate tuning parameter. Once trained, this model can be used to automatically estimate the tuning parameter value necessary to achieve the desired operating preemption rates. Simulation results show that the preemption rate attained by the model closely matches with the target rate.     

Rapid Synthesis of Cobalt Metal Organic Framework

Metal-organic framework (MOF) has been shown to potential applications due to the high porous hybrid structure. Cobalt MOF was synthesized rapidly by ultrasound energy with about 3,000 m²/g surface area by BET method. Furthermore, this component is crystalline with significant thermal stability, on account of X-ray diffraction and thermal analysis, respectively. Based on high roughness, crystallinity, and unreported type of FTIR spectrum, a new structure of Co-MOF structure was proposed.     

Utilisation of iron ore mine tailings for the production of geopolymer bricks

This study presents a methodology for making bricks, in a cost-effective and environmentally friendly manner, using the tailings produced from iron ore mines in Western Australia (WA). The study was based on the geopolymerisation process, which is known to conserve energy by reducing the emission of greenhouse gases. The reduction is accomplished by avoiding the processes of high temperature kiln firing, traditionally utilised when making bricks from sandy soils with high clay content. In this study, the sodium silicate was added to the mine tailings in powder form, as an activator for the formulation of the geopolymer bricks. The effects of the initial setting time, curing temperature, curing time and activator content on the unconfined compressive strength (UCS), water absorption and other durability properties of the bricks were investigated. X-ray diffraction analysis was performed to investigate the phase composition of the geopolymer bricks. The bricks achieved an UCS as high as 50.53 MPa for the optimum values of the parameters. Technically, the geopolymer bricks that were produced met both the American Society of Testing and Materials and the Australian Standards (AS) requirements for bricks. A cost analysis of the geopolymer bricks is also presented, and this shows that the cost of geopolymer bricks is lower than that of the commercial, fired clay bricks.     

Efficient optimization of network protection design with <Emphasis Type="Italic">p</Emphasis>-cycles

The purpose of this paper is to consider network survivability designs that utilize the p-cycle, and to propose a novel ILP formulation for capacity design based on network fundamental cycles, as well as the available straddling links. Concepts of visible and hidden straddling links—which are essential components of the model presented herein—are also introduced. The proposed model caters for the case of joint optimization of a p-cycle network that can be solved without enumerating p-cycle candidates. In addition, the complexity of the proposed model is much less than any conventional model dealing with large size networks and suitable for the design of networks having multiple quality of protection (MQoP) service classes using mixed protection techniques.     

Flexible Prime‐Field Genus 2 Hyperelliptic Curve Cryptography Processor with Low Power Consumption and Uniform Power Draw

This paper presents an energy‐efficient (low power) prime‐field hyperelliptic curve cryptography (HECC) processor with uniform power draw. The HECC processor performs divisor scalar multiplication on the Jacobian of genus 2 hyperelliptic curves defined over prime fields for arbitrary field and curve parameters. It supports the most frequent case of divisor doubling and addition. The optimized implementation, which is synthesized in a 0.13 μm standard CMOS technology, performs an 81‐bit divisor multiplication in 503 ms consuming only 6.55 μJ of energy (average power consumption is 12.76 μW). In addition, we present a technique to make the power consumption of the HECC processor more uniform and lower the peaks of its power consumption.     

Optimization of pH sensing using silicon nanowire field effect transistors with HfO2 as the sensing surface

Silicon nanowire field effect transistor sensors with SiO(2)/HfO(2) as the gate dielectric sensing surface are fabricated using a top down approach. These sensors are optimized for pH sensing with two key characteristics. First, the pH sensitivity is shown to be independent of buffer concentration. Second, the observed pH sensitivity is enhanced and is equal to the Nernst maximum sensitivity limit of 59 mV/pH with a corresponding subthreshold drain current change of ～ 650%/pH. These two enhanced pH sensing characteristics are attributed to the use of HfO(2) as the sensing surface and an optimized fabrication process compatible with silicon processing technology.     

Interfaces for high speed fiber-optic links: analysis andexperiment

An analysis of directly and externally modulated fiber-optic links is presented. The theoretical analysis is based on the signal flow diagram of the interface circuits to the laser diode, Mach-Zehnder electro-optic modulator, and p-i-n photodiode. System parameters such as gain, noise figure, two-tone intermodulation distortion, and spurious free and compression dynamic range are expressed as a function of frequency and operating point of the laser and external modulator. Two directly and externally modulated fiber-optic links were designed and fabricated to verify the analytical models. The direct modulation FO link was developed at the Ku-band (11.6-12.4 GHz), whereas the external modulation link was at L-band (875-925 MHz). Spurious-free dynamic ranges of 95.8 dB Hz^2/3 and 113 dB Hz ^2/3, respectively, were achieved. The predictions based on the analytical models match the measured results