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With the rapid development of computer networks, the network architecture has been more and more complex and diverse. Smart grid is a kind of wireless sensor network consuming energy in smart city. Smart grid communications have developed rapidly in recent years, while the privacy, integrity and confidentiality of user data have been the main security issues. However, lattice-based homomorphic cryptography can resist quantum attacks and effectively provide the security of the scheme. In this paper, we proposed an aggregate signature scheme based on new Batch RSA. After that, a data aggregation scheme is proposed based on this aggregate signature scheme and the qualified homomorphic cryptosystem. Compared with the previous schemes, our scheme is more secure because we implement seven properties, such as post quantum, privacy and so on. Compared with the representative scheme proposed by Abdallah et al., our scheme has lower computation and communication overhead. In addition, the cryptographic algorithms involved in our scheme are lightweight. The network model in our scheme is suitable for large intelligent communities. So our scheme is very suitable for residential area network.

SUMMARYThe strategies adopted by viruses to reprogram the protein translation and quality control machineries to promote infection are poorly understood. Here, we discovered that the viral ubiquitin deconjugase (vDUB) encoded in the large tegument protein of Epstein- Barr virus (EBV) regulates ribosomal stress responses. The vDUB participates in protein complexes that include the ubiquitin ligases ZNF598 and LTN1 and the UFM1 ligase UFL1. Upon ribosomal stalling, the vDUB counteracts the ubiquitination of 40S ribosome subunits, inhibits the degradation of translation-stalled polypeptides by the proteasome, and prevents UFMylation of the 60S particle, which impairs the ER-phagy- dependent clearance of stalled products. Inhibition of the ribosome quality control activates a GCN2-dependent integrated stress response that decreases global protein translation while promoting the readthrough of stall-inducing mRNAs. The vDUB enhances viral mRNAs translation and virus release during productive infection, pointing to a pivotal role in cell reprogramming that enables virus production and underlies the pathogenesis of EBV-associated cancers and autoimmune diseases.GRAPHIC SUMMARY

The mechanical properties of Al matrix composites reinforced by AlCoCrFeNi high entropy alloy particles were greatly enhanced after spark plasma sintering at 600 °C accompanied with the formation of reinforcement core–shell structure. The dependence of mechanical properties and fracture behavior of the composites on the reinforcement core–shell structure was investigated and discussed based on the modified Ramakrishnan model and finite element simulation. The FCC equiaxed grains (Shell-1) and BCC columnar grains (Shell-2) were found in the shell. Thus, three kinds of interfaces were generated in the composite, where there is a coherent relationship between Shell-1 and Al matrix. The shell with appropriate plasticity can restrain cracks propagation and is considered as one part of matrix during analyzing cracks nucleation and propagation. However, the core–shell structure segments the Al matrix and the shell is regarded as one of reinforcement during inspecting the yield strength. Thus, as compared with the composite without core–shell structure, at 5 vol.%, 10 vol.%, and 15 vol.% plasticity of composites with core–shell structure is respectively improved by 42.7%, 6.6%, and 3.2%. Meanwhile, the yield strength is increased about 1.9 times higher of the composites with HEA volume fraction at 15%.

Si3N4/TaC composite MAO coatings were fabricated by microarc oxidation (MAO) on a Ti–6Al–4V (TC4) alloy in a phosphate-based electrolyte containing Si3N4/TaC mixed particles. The influence of the amount of Si3N4/TaC particles on the microstructure, composition, tribological behavior, and corrosion properties of the MAO coatings has been investigated. Morphological research of the MAO coatings was carried out using scanning electron microscopy (SEM), with the surface porosity analyzed by ImageJ software. X-ray diffraction (XRD) was used for the detection of the phase characteristic of the MAO coatings, and an abrasive wear test and electrochemical measurements were conducted in the artificial seawater solution by the ball-on-disc friction tester and the electrochemical workstation, respectively. The results showed that Si3N4/TaC particles could be successfully incorporated into the composite coatings, and the addition of Si3N4/TaC particles greatly reduced the porosity of the coatings, thus improving both tribological and corrosion properties of the composite MAO coatings. The composite MAO coating with the addition of 1 g/L Si3N4 + 0.5 g/L TaC particles showed the best tribological property and the optimum corrosion properties.

Significant efforts are being put into the development of efficient micrometer-scale light emitting diodes (LEDs) for future display technologies due to their marked benefits over existing displays. To date, however, the efficiency of microLED devices remains significantly lower than that of conventional broad-area devices. The deterioration in device performance with smaller device size has been linked to the plasma damage induced on mesa sidewalls during device fabrication. Here, we studied bottom-up red-emitting nanowire LEDs with different Mg doping levels in the p-GaN layer. The resulting sub-micron LED devices show a distinct improvement in efficiency with increasing Mg dopant incorporation. Through optimization of the doping, we measured an external quantum efficiency of ∼8.3% and a wall-plug efficiency of ∼4.6%, at a current density of ∼1 A/cm2, for a red-emitting sub-micrometer scale LED operating at >630 nm. This study highlights the importance of p-doping in microLEDs for attaining high efficiency performance in nanostructure-based devices.

III-nitride semiconductors are promising optoelectronic and electronic materials and have been extensively investigated in the past decades. New functionalities, such as ferroelectricity, ferromagnetism, and superconductivity, have been implanted into III-nitrides to expand their capability in next-generation semiconductor and quantum technologies. The recent experimental demonstration of ferroelectricity in nitride materials, including ScAl(Ga)N, boron-substituted AlN, and hexagonal BN, has inspired tremendous research interest. Due to the large remnant polarization, high breakdown field, high Curie temperature, and significantly enhanced piezoelectric, linear and nonlinear optical properties, nitride ferroelectric semiconductors have enabled a wealth of applications in electronic, ferroelectronic, acoustoelectronic, optoelectronic, and quantum devices and systems. In this review, the development of nitride ferroelectric semiconductors from materials to devices is discussed. While expounding on the unique advantages and outstanding achievements of nitride ferroelectrics, the existing challenges and promising prospects have been also discussed.

XRD results show that diffraction peak of M3B is gradually apparent with the increase of annealing temperature and time, which indicates that annealing can promote the formation of M3B phase. The i...

The accurate and fast diagnosis of transformer winding deformation faults is of significance to power suppliers and utilities. An improved winding mechanical deformation fault classification method is proposed. In this study, the transformer frequency response data is used to draw polar plots, and then its texture features are extracted for fault classification. The classification model constructed by multiple support vector machines is successfully obtained and shows good classification effect. Besides, this article uses an improved genetic algorithm based on the Emperor-Selective mating scheme and catastrophic operation, to optimize the parameters of support vector machine. The feasibility and accuracy of the proposed method are verified with experimental data obtained from a model transformer, and the proposed method is demonstrated to exhibit better performance compared with the traditional method.

Herein, strongly coupled Mo2C and Ni nanoparticles with in-situ formed interfaces encapsulated by porous carbon nanofibers (Ni-Mo2C-CNF) have been rationally fabricated via pyrolyzing electrospinning polyvinyl alcohol fibers containing hydrothermally obtained NiMoO4 under Ar atmosphere and applied as high-performance and stable electrocatalyst for HER in alkaline electrolytes. Powered by NiMoO4 as homologous bimetallic precursor, the Ni-Mo2C-CNF possesses numerous in-situ formed Ni-Mo2C interfaces, which facilitates the synergistic effect between Ni and Mo2C, improving the conductivity and thus boosting the electrocatalytic performance towards HER. In the meantime, the porous carbon nanofibers with well encapsulated Ni-Mo2C active components stacks, constituting conductive network, which promotes the mass transport, electron transfer, active sites exposure and electrocatalytic stability. As a result, the Ni-Mo2C-CNF features prominently in HER, as it demands a low overpotential of 196 mV but is able to stably yield the current density of 10 mA cm−2 with a small Tafel plot of 54.7 mV dec−1. The method demonstrated in our work to synthesize bimetallic heterostructured materials will offer valuable inspiration to construct promising non-precious electrocatalysts for diverse vital renewable energy applications.

In this Letter, we demonstrated fully epitaxial ScAlN/AlGaN/GaN based ferroelectric high electron mobility transistors (HEMTs). Clean and atomically sharp heterostructure interfaces were obtained by utilizing molecular beam epitaxy. The fabricated ferroelectric gate HEMTs showed counterclockwise hysteretic transfer curves with a wide threshold voltage tuning range of 3.8 V, a large ON/OFF ratio of 3 × 107, and reconfigurable output characteristics depending on the poling conditions. The high quality ferroelectric gate stack and effective ferroelectric polarization coupling lead to improved subthreshold performance, with subthreshold swing values approaching 110 and 30 mV/dec under forward and backward gate sweeps, respectively. The results provide fundamental insight into the ferroelectric polarization coupling and threshold tuning processes in ferroelectric nitride heterostructures and are promising for nitride-based nonvolatile, multi-functional, reconfigurable power, and radio frequency devices as well as memory devices and negative capacitance transistors for next-generation electronics.

The cloud's flexibility and promise of seamless auto-scaling notwithstanding, its ability to meet service level objectives (SLOs) typically calls for some form of control in resource usage. This seemingly traditional problem gives rise to new challenges in a cloud setting, and in particular a subtle yet significant trade-off involving load-distribution decisions (the distribution of workload across available cloud resources to optimize performance), and rate limiting (the capping of individual workloads to prevent global over-commitment). This paper investigates that trade-off through the design and implementation of a real-time messaging system motivated by Internet-of- Things (IoT) applications, and demonstrates a solution capable of realizing an effective compromise. The paper's contributions are in both explicating the source of this trade-off, and in demonstrating a possible solution.

Topoisomerases are essential for the replication of herpesviruses but the mechanisms by which the viruses hijack the cellular enzymes are largely unknown. We found that topoisomerase-II (TOP2) is a substrate of the Epstein-Barr virus (EBV) ubiquitin deconjugase BPLF1. BPLF1 co-immunoprecipitated and deubiquitinated TOP2, and stabilized SUMOylated TOP2 trapped in cleavage complexes (TOP2ccs), which halted the DNA damage response to TOP2-induced double strand DNA breaks and promoted cell survival. Induction of the productive virus cycle in epithelial and lymphoid cell lines carrying recombinant EBV encoding the active enzyme was accompanied by TOP2 deubiquitination, accumulation of TOP2ccs and resistance to Etoposide toxicity. The protective effect of BPLF1 was dependent on the expression of tyrosyl-DNA phosphodiesterase 2 (TDP2) that releases DNA-trapped TOP2 and promotes error-free DNA repair. These findings highlight a previously unrecognized function of BPLF1 in supporting a non-proteolytic pathway for TOP2ccs debulking that favors cell survival and virus production., Author summary The N-terminal domains of the herpesvirus large tegument proteins encode a conserved cysteine protease with ubiquitin- and NEDD8-specific deconjugase activity. Members of the viral enzyme family regulate different aspects of the virus life cycle including virus replication, the assembly of infectious virus particles and the host innate anti-viral response. However, only few substrates have been validated under physiological conditions of expression and very little is known on the mechanisms by which the enzymes contribute to the reprograming of cellular functions that are required for efficient infection and virus production. Cellular type I and type II topoisomerases (TOP1 and TOP2) resolve topological problems that arise during DNA replication and transcription and are therefore essential for herpesvirus replication. We report that the Epstein-Barr virus (EBV) ubiquitin deconjugase BPLF1 selectively regulates the activity of TOP2 in cells treated with the TOP2 poison Etoposide and during productive infection. Using transiently transfected and stable cell lines that express catalytically active or inactive BPLF1, we found that BPLF1 interacts with both TOP2α and TOP2β in co-immunoprecipitation and in vitro pull-down assays and the active enzyme stabilizes TOP2 trapped in TOP2ccs, promoting a shift towards TOP2 SUMOylation. This hinders the activation of DNA-damage responses and reduces the toxicity of Etoposide. The physiological relevance of this finding was validated using pairs of EBV carrying HEK-293T cells and EBV immortalized lymphoblastoid cell lines (LCLs) expressing the wild type or catalytic mutant enzyme. Using knockout LCLs we found that the capacity of BPLF1 to rescue of Etoposide toxicity is dependent on the expression of tyrosyl-DNA phosphodiesterase 2 (TDP2) that releases DNA-trapped TOP2 and promotes error-free DNA repair.

To achieve high quality, strong adaptability, and stability of visible light communication system, this paper plans to study the hemispherical array structure to realize the alignment of the light path. The structured surface covers multiple LED and PD detection arrays according to the longitude and weft direction, realizing the bidirectional sending and receiving model. It is demonstrated that the effective light intensity ratio of the hemispherical array is higher than that of the planar array, and the interference between channels of the hemispherical array is less than that of the planar array under the same conditions. In addition, the influence mechanism of optical mechanism parameters (transceiver hemisphere array radius, LED tilt angle, and PD tilt angle) on beam scattering is established, and the influence of relative position changes between LED array and PD array on communication performance is clarified.

[Purpose/meaning] Due to its potential impact on business efficiency, automated customer complaint labeling and classification are of great importance for management decisions and business-level applications. The majority of the current research on automated labeling uses large and well-balanced datasets. However, customer complaints' labels are hierarchical in structure, with many labels at the lowest hierarchy level. Relying on lower-level labels leads to small and imbalanced samples, thus rendering the current automatic labeling practices not applicable to customer complaints. [Methodology/process] This article proposes an automatic labeling model incorporating the BERT and Word2Vec methods. The model is validated on electric utility customer complaints data. Within the model, the BERT method serves to obtain shallow-level text tags. Further, text enhancement is used to mitigate the problem of uneven samples that emerges when the number of labels is large. Finally, the Word2Vec model is utilized for the deep-level text analysis. [Findings/conclusions] The experiments demonstrate the proposed model's efficiency in automating customer complaint labeling. Consequently, the proposed model supports the enterprises in improving their service quality while simultaneously reducing labor costs.

The AlFeCoNiBx (x = 0, 0.05, 0.10, 0.15, 0.2) high entropy alloys are prepared by vacuum arc melting. The effect of B on the microstructure and mechanical behaviors of the alloys are systematically investigated. X-Ray Diffraction results and Electro-Probe Microanalyzer results show that small amount of B atoms are dissolved into B2 matrix and the other B atoms result in the formation of FCC phase. The addition of B content leads to transformation of microstructure from pure B2 phase to “B2 phase + particle FCC structure” and then to “B2 phase + eutectic structure”. Eutectic structure consists of FCC1 phase and FCC2 phase. FCC1 phase is rich in Co and Ni and FCC2 phase is rich in B, Fe and Co. With the increase of B content, grain size of B2 phase firstly reduce and then increase. By increasing the B content from 0 to 0.2, fracture strength and plastic strain increase from 850 MPa to 2293 MPa and 0.07 to 0.27 respectively. The increase of yield strength is due to the solid solution strengthening and fine grain strengthening of boron atom. While, the increase of plasticity is due to the formation of FCC eutectic structure.

The 5 vol% AlCoCrFeNi high-entropy alloy (HEA) reinforced Al matrix composites were fabricated successfully by spark plasma sintering at the temperatures ranging from 540 °C to 600 °C. At 540 °C, there is a smooth interface between HEA reinforcement and Al matrix. At the sintering temperature above 560 °C, the melting of particle-contacting zone between HEA reinforcement and Al matrix leads to the formation of a transition layer with a single FCC phase. Furthermore, its thickness increases with increasing sintering temperature. This is favorable for the transformation of the stress state from the iso-stress condition to the iso-strain condition for the composites during deformation process. Therefore, both yield strength and ductility are significantly improved. The yield strength and compressive strain of composites without transition layer are 96 MPa and 36%, respectively. In contrast, the yield strength of composites containing the transition layer with an average thickness of 7.6 μm is about 137 MPa and no macroscopic fracture can be observed in the Al matrix composite after 50% compression strain. This work can provide guidance for fabrication of HEA/Al composites with high strength and good plasticity.

As an important part of power system, power transformer plays an irreplaceable role in the process of power transmission. Diagnosis of transformer's failure is of significance to maintain its safe and stable operation. Frequency response analysis (FRA) has been widely accepted as an effective tool for winding deformation fault diagnosis, which is one of the common failures for power transformers. However, there is no standard and reliable code for FRA interpretation as so far. In this paper, support vector machine (SVM) is combined with FRA to diagnose transformer faults. Furthermore, advanced optimization algorithms are also applied to improve the performance of models. A series of winding fault emulating experiments were carried out on an actual model transformer, the key features are extracted from measured FRA data, and the diagnostic model is trained and obtained, to arrive at an outcome for classifying the fault types and degrees of winding deformation faults with satisfactory accuracy. The diagnostic results indicate that this method has potential to be an intelligent, standardized, accurate and powerful tool.