Recent Study on Schottky Tunnel Field Effect Transistor for Biosensing Applications

Silicon - In this review, we discussed highly sensitive biosensor devices which is having a more attractive, wide scope and development in the sensing field. Biosensor devices can detect the...     

Engineering education and industrial research and development-thepromise and the reality

The author observes that the social fabric of engineering, the support infrastructure of the profession, and the political and economic systems of the world are undergoing shifts that affect what engineering is, how it is accomplished, and what it should do. He asks what these changes mean in terms of the educational system and explores a few of these issues that lie between academia and the industrial environment beyond. He discusses the engineering curriculum as seen from industry, the role of continuing education, research in academia     

Improved error performance of a 3/4‐Sezginer space‐time block codes

The Alamouti space‐time block code (STBC) achieves full diversity gain at a rate of 1/2. However, the Alamouti scheme does not provide multiplexing gain. The Silver code offers both diversity and multiplexing gain. It has a minimum normalization determinant of . The Golden code is another STBC that offers both diversity and multiplexing gain. The Golden code is ranked higher than the Silver code because of its lower minimum normalization determinant of , however, the golden code suffers from a high detection complexity in the modulation order of M⁴. The 3/4‐Sezginer code is another STBC, which compromises between the Alamouti scheme and the Golden code in terms of diversity gain and multiplexing gain. The 3/4‐Sezginer code achieves full diversity and half of multiplexing gain. The uncoded space‐time labeling diversity (USTLD) is a recent scheme that improves the error performance when applied to the STBC in multiple‐input multiple‐output (MIMO) systems and will be applied to the 3/4‐Sezginer STBC to improve the error performance in this paper. The theoretical error probability for both the 3/4‐Sezginer STBC and the improved system is formulated using the union bound in this paper. The theoretical error probabilities of both 16‐QAM and 64‐QAM are validated through Monte Carlo simulation. The simulation and theoretical results show that the proposed system with 4 N_R can achieve an SNR gain of 1 dB for 16‐QAM and 1.2 dB 64‐QAM at a bit error rate (BER) of 10^?6.     

An efficient authentication with key agreement procedure using Mittag–Leffler–Chebyshev summation chaotic map under the multi-server architecture

The recent technological advancement and rapid development of computer networks have increased the popularity of remote password authentication protocols. Toward this end, the emphasis has shifted to protocols that apply to smart cards-empowered multi-server environments. In order to defend against the replay attack, these protocols usually depend on the nonce or timestamp. In this paper, an efficient Mittag–Leffler–Chebyshev Summation Chaotic Map (MLCSCM)-enabled multi-server authentication protocol with the key agreement is proposed and generalized to address this peculiarity in multi-server-oriented applications. The security proof and efficiency analysis of the presented MLCSCM authenticated key agreement protocol is rigorously derived and validated. Compared to the recently published literature, the proposed protocol presents high efficiency with unique features, and it is highly resistant to sophisticated attacks and achieves perfect forward secrecy.

     

Conformation mediated preferential swelling of amphiphilic block copolymer ultrathin films

Steady-state and dynamic swelling characteristics of PEO-PPO-PEO copolymer ultrathin films comprising 2-layered structure, where the bottom layer (L1) is made of one PEO (hydrophilic)-PPO (hydrophobic) bilayer and the top layer (L2) is made of two alternating PEO-PPO bilayers, have been studied at room temperature in precisely controlled environment of 10–93% relative humidity (RH). Swelling, which is monitored by measuring the thickness of the films using X-ray reflectivity (XRR), is found to be largely dissimilar in differently thick films prepared by varying the concentration of mother solutions from 1 g/L to 4 g/L. This is well explained considering a preferential-swelling of amphiphilic block copolymer, where only the hydrophilic PEO blocks contribute in swelling and PPO acts a barrier in the diffusion of water molecules. The swelling kinetics is governed by the thickness/width and coverage of outer PPO block layer.

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Graphical abstract Steady-state and dynamic swelling characteristics of PEO-PPO-PEO triblock copolymer ultrathin films comprising 2-layered structure, where the bottom layer is made of one PEO (hydrophilic)-PPO (hydrophobic) bilayer and the top layer is made of two alternating PEO-PPO bilayers, have been studied at room temperature in precisely controlled environment of 10–93% relative humidity (RH). Swelling, which is monitored by measuring the thickness of the films using X-ray reflectivity (XRR), is found to be largely dissimilar in differently thick films prepared by varying the concentration of mother solutions from 1 g/L to 4 g/L. This is well explained considering a preferential-swelling of amphiphilic triblock copolymer, where only the hydrophilic PEO blocks contribute in swelling and PPO acts a barrier in the diffusion of water molecules. The swelling kinetics is governed by the thickness/width and coverage of outer PPO block layer.

     

WO3 nanomaterials synthesized via a sol-gel method and calcination for use as a CO gas sensor

Carbon monoxide is a poisonous and hazardous gas and sensitive sensor devices are needed to prevent humans from being poisoned by this gas. A CO gas sensor has been prepared from WO₃ synthesized by a sol-gel method. The sensor chip was prepared by a spin-coating technique which deposited a thin film of WO₃ on an alumina substrate. The chip samples were then calcined at 300, 400, 500 or 600 °C for 1 h. The sensitivities of the different sensor chips for CO gas were determined by comparing the changes in electrical resistance in the absence and presence of 50 ppm of CO gas at 200 °C. The WO₃ calcined at 500 °C had the highest sensitivity. The sensitivity of this sensor was also measured at CO concentrations of 100 ppm and 200 ppm and at operating temperatures of 30 and 100 °C. Thermogravimetric analysis of the WO₃ calcined at 500 °C indicated that this sample had the highest gas adsorption capacity. This preliminary research has shown that WO₃ can serve as a CO gas sensor and that is should be further explored and developed.