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101.
The Journal of Supercomputing - Building sentiment analysis resources is a fundamental step before developing any sentiment analysis model. Sentiment lexicons are one of these critical resources....  相似文献   
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The major challenge in wireless body area networks (WBAN) is setting up a protected communication between data consumers and a body area network controller while meeting the security and privacy requirements. This paper proposes efficient and secure data communication in WBANs using a Twofish symmetric algorithm and ciphertext‐policy attribute‐based encryption with constant size ciphertext; in addition, the proposed scheme incorporates policy updating to update access policies. To the best of the author's knowledge, policy updating in WBAN has not been studied in earlier works. The proposed scheme is evaluated in terms of message size, energy consumption, and computation cost, and the results are compared with those of existing schemes. The result shows that the proposed method can achieve higher efficiency than conventional methods.  相似文献   
105.
In this research article, a triangular‐shaped microwave network cloak made out of interconnected patches was designed at the frequency of 2.88 GHz. Its performances in terms of field distributions and radar cross section scattering were compared with the existing structures. The novel triangular‐shaped cloak structure was then applied to cloak a hindering obstacle placed in front of an electromagnetic source. The simulated scattering parameter and radiation pattern of antenna source were then validated through the experimental results. Also, the proposed structure was applied to reduce the mutual interference between two neighboring antennas. The effects of various parameters such as position and size of the cloak, dielectric constant, and substrate thickness on the cloaking effect were also simulated and studied.  相似文献   
106.
We have examined both single and entangled two-mode multiphoton coherent states and shown how the ‘Janus-faced’ properties between two partner states are mirrored in appropriate tomograms. Entropic squeezing, quadrature squeezing and higher-order squeezing properties for a wide range of nonclassical states are estimated directly from tomograms. We have demonstrated how squeezing properties of two-mode entangled states produced at the output port of a quantum beamsplitter are sensitive to the relative phase between the reflected and transmitted fields. This feature allows for the possibility of tuning the relative phase to enhance squeezing properties of the state. Finally, we have examined the manner in which decoherence affects squeezing and the changes in the optical tomogram of the state due to interaction with the environment.  相似文献   
107.

Nowadays, sensing and detection of ethanol is paramount one for numerous applications including production of ethanol, fuel processing, chemical processing in industry, traffic management, food package testing for safety and medical applications. On the other hand, the rapid growth of nanotechnology paves the way to develop highly sensitive, portable and low-cost sensors with less power consumption. In line with this fact, a cladding modified fiber optic ethanol sensor using CdS nanoflower has been reported in the present study. CdS nanoflower was prepared by one step hydrothermal synthesis and subjected for various characterization techniques to investigate the material properties. The sensor probe was developed viz cladding modification technology followed by dip coating of CdS nanoflower over an unclad section of an optical fiber. The potency of CdS nanoflower has been probed for 0–300 ppm of acetone, ethanol, methanol and isopropanol at ambient environment. The sensing results demonstrates that the sensor coated with CdS nanoflower manifested better sensing performances towards ethanol (~?4.6% at 300 ppm) with response/recovery of 90 s and 100 s than other gases. The unique sensing feature complied that CdS nanoflower is desirable candidate in effective quantification of ethanol.

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108.
Summary The monomer reactivity ratios of methyl phenoxymethacrylate (MPMA), methyl p-cresoxymethacrylate (MCMA) and methyl p-nitrophenoxymethacrylate (MNMA) were evaluated both by Fineman-Ross and Kelen-Tüdös methods. The tendency to form alternating copolymers of these monomers is discussed.  相似文献   
109.
This paper presents a new model-reference adaptive control method based on a bi-objective optimal control formulation for systems with input uncertainty. A parallel predictor model is constructed to relate the predictor error to the estimation error of the control effectiveness matrix. In this work, we develop an optimal control modification adaptive control approach that seeks to minimize a bi-objective linear quadratic cost function of both the tracking error norm and the predictor error norm simultaneously. The resulting adaptive laws for the parametric uncertainty and control effectiveness uncertainty are dependent on both the tracking error and the predictor error, while the adaptive laws for the feedback gain and command feedforward gain are only dependent on the tracking error. The optimal control modification term provides robustness to the adaptive laws naturally from the optimal control framework. Simulations demonstrate the effectiveness of the proposed adaptive control approach.   相似文献   
110.
We carried out a comparative study on the electrical and magnetodielectric properties of polycrystalline BiFeO3, Bi0.9Ca0.1FeO2.95, Bi0.9Ba0.05Ca0.05FeO2.95, and Bi0.9Ba0.1FeO2.95 ceramics. The two dielectric anomalies, near 25 K and 281 K, are observed for BiFeO3. Interestingly, the anomaly near 25 K shifts towards a higher temperature above 60 K with Ca and/or Ba doping, attributed to the doping induced chemical pressure. In addition, the room temperature switchable magnetodielectric effect is witnessed for the doped BiFeO3 compounds, due to the quadratic magnetoelectric coupling. This indicates the improved magnetoelectric coupling in BiFeO3 with the Ca and Ba doping. This is essentially due to the enhanced magnetic ordering and reduced leakage current in BiFeO3 after the doping.  相似文献   
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