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The sudden load changes impact power grids by frequency and power oscillations. In order to distinguish the complex and massive abnormal user load data， this paper proposes a method combining multiple features and LOF （local outlier factor） algorithm. Firstly， the statistical characteristic mean value， standard deviation， waveform characteristic dispersion coefficient， kurtosis， waveform factor and pulse factor of load data are extracted， and the effective features are obtained through dimensionality reduction of PCA （principal component analysis）. Furthermore， the LOF algorithm is used to detect abnormal user load data every day. This detection algorithm is used in the Zhejiang power data center based on Alibaba cloud. The results show that it can detect users with abrupt load changes in massive measured data at fixed times of every day and realizes online detection with high accuracy.

Li6PS5Cl (LPSC), a sulfide solid-state electrolyte with an argyrodite structure, is one of the ideal electrolyte materials for the construction of all-solid-state lithium-ion batteries.It has good development prospects because of its high ionic conductivity (>3×10-3 S·cm-1) and good stability to lithium. In this work, LPSC was prepared by the combination of high-energy ball milling and inert atmosphere solid-phase sintering, and powder X-ray diffraction, Raman spectra, and scanning electron microscopy were used to investigate the effects of the preparation process on the structure, composition, electrical properties, and ion conductivity of LPSC. The results show that the extended ball milling time is beneficial to the amorphization and subsequent sintering of the LPSC precursor powder. The increase of the sintering temperature will promote the physical purity and electrical conductivity of the prepared LPSC electrolyte, but the high sintering temperature will lead to the decomposition of LPSC. The LPSC prepared by 8 h ball milling and 500℃ sintering has the highest ion/electron conductivity ratio (2.091×105) at room temperature, with ionic conductivity up to 4.049×10-3 S·cm-1 and electronic conductivity only 1.936×10-8 S·cm-1. The 712 NCM/LPSC/In-Li all-solid-state battery prepared with this electrolyte has a first-turn discharge specific capacity of 151.3 mAh·g-1 at a charge/discharge ratio of 0.1 C, and has excellent cycling stability.

Traditional multicast routing strategies can hardly meet the demanding requirements of multicasting mission assignment messages in airborne tactical networks. This letter proposes an intent‐driven routing strategy, termed as IDR, to realize reliable and efficient multicast. IDR exploits bit index explicit replication technique to encode not only the destination information but also the retransmission information into packet headers. If part of the multicast members failed to receive the packet, IDR can perceive the error and retransmit the packet to the precise set of nodes. Compared to the state‐of‐the‐art reliable multicast routing methods, IDR can enhance multicast retransmission success rate by about 10% or more and reduce retransmission overhead by around 50%. [ABSTRACT FROM AUTHOR]

Salmonella enterica is one of the most common bacterial pathogens in humans and animals. Systematic studies on the trends and geographical distribution of antimicrobial-resistant Salmonella and dominant serovars have been well studied in European and American countries while not in China. Here, taking the One-Health strategy, we used >35 000  Salmonella enterica isolates to explore the temporal and spatial dynamics of dominant serovars in China. We found that Salmonella Typhimurium was the dominant serovar causing human infection in China, which was consistent with Australia but inconsistent with North American and European countries. The proportion of Salmonella serovars Typhimurium, London, Rissen, Corvallis, Meleagridis, Kentucky, and Goldcoast showed an increasing trend during 2006–2019. We randomly selected 1962 isolates for comparative genomics and antimicrobial resistance studies and found that the number of antibiotic resistance genes (ARGs) per isolate increased 1.84 and 2.69 times of human and non-human origins, respectively, spanning 14 years. The proportion of antimicrobial-resistant Salmonella isolates had an increasing trend during 2006–2019, especially beta-lactam, quinolone, tetracycline, and rifampicin resistance. Moreover, we found that higher diversity of sequence types (STs) in S. Typhimurium than in other serovars, ST34 from pig and ST19 from chicken origin, were mainly associated with isolates causing child and adult gastro-infection, respectively. Our results fill in the data gap on the trends of dominant serovars and antimicrobial resistance of Salmonella enterica in China. These data provide useful information for public health decision-makers prioritizing interventions for foodborne diseases and food safety. [ABSTRACT FROM AUTHOR]

During the rolling process of profile ring, the design of the rolling cavity directly affects the forming quality of the final ring. In order to improve the cavity filling rate and reduce the production cycle time, this paper proposes a general evaluation method of the filling difficulty for profile ring rolling cavity by combining the response surface method(RSM) and the finite element method(FEM) with the step-type ring as the research object. Firstly, a universally applicable design method for profile ring rolling cavity is proposed, and based on the description of the rolling cavity, three design variables and a corresponding response objective are defined to achieve multi-objective optimization. Secondly, a finite element model of this step-type ring rolling process is established, and the response model is built and improved by significance analysis and analysis of variance(ANOVA) based on the forming simulation results. Then, the effects of different variables on the optimization objectives are comprehensively investigated by this response model. Finally, the evaluation method of the filling difficulty for profile ring rolling cavity is obtained by combining the contour plot of the response objective.

In view of the problem that the current asynchronous network update method takes a long time to update and can not avoid updating deadlock, in order to reduce the network performance loss during updating, a time-based update method for airborne network of aviation swarm is proposed. Considering the real link delay, the time parameter is combined with the update dependency graph. Firstly, a time-based update dependency graph is constructed. Secondly, a greedy scheduling algorithm is designed to allocate the update time step for each update operation. Finally, the timed network update is realized and the update sequence coordination in asynchronous update is avoided. Simulation experiments show that compared with the existing asynchronous updating methods, the update time can be reduced by 50%~60% through the proposed timing update method, and the update deadlock rate and the network congestion are reduced during the network update. [ABSTRACT FROM AUTHOR]

To solve the problem of control node failure in the control domain of software-defined airborne network of the aviation swarm, the problem of failure recovery is transformed into the issue of leader election, and an election-based software-defined airborne network controller failure recovery mechanism is proposed, and the transmission node is elected as a new control one in the control domain. To optimize the performance of the new control node, the three parameters of the average transmission delay, the maximum request amount and the average failure rate of each transmission node are combined to calculate the weight of the transmission node. The election priority is defined according to the weight, and a priority-based control node election (PBCNE) algorithm is proposed. The experimental results show that compared with the existing election algorithms, the complexity (number of messages and amount of time) of the PBCNE algorithm has been significantly reduced, the failure recovery delay has been effectively reduced, and the controller failure can be recovered quickly and efficiently. [ABSTRACT FROM AUTHOR]