Metering data from the advanced metering infrastructure can be used to find abnormal electricity behavior for the detection of electricity theft, which causes huge financial losses to electric ...companies every year. This article proposes an electricity theft detector using metering data based on extreme gradient boosting (XGBoost). The metering data are preprocessed, including recover missing and erroneous values and normalization. The classification model based on XGBoost is trained using both benign and malicious samples. Simulations are done by using the Irish Smart Energy Trails data set with six certain attack types. Compared with the support vector machine, decision tree, and other eight machine learning methods, the proposed method can detect electricity theft with either higher accuracy or lower false-positive rate. Experiment results also demonstrate that the proposed method is robust when the data are imbalanced. Our codes are available at https://github.com/WenHe-Hnu/Electric_Theft_XGBoost .
Recently, quantum anomalous Hall effect with spontaneous ferromagnetism was observed in twisted bilayer graphenes (TBG) near 3/4 filling. Importantly, it was observed that an extremely small current ...can switch the direction of the magnetization. This offers the prospect of realizing low energy dissipation magnetic memories. However, the mechanism of the current-driven magnetization switching is poorly understood as the charge currents in graphenes are generally believed to be non-magnetic. In this work, we demonstrate that in TBG, the twisting and substrate induced symmetry breaking allow an out of plane orbital magnetization to be generated by a charge current. Moreover, the large Berry curvatures of the flat bands give the Bloch electrons large orbital magnetic moments so that a small current can generate a large orbital magnetization. We further demonstrate how the charge current can switch the magnetization of the ferromagnetic TBG near 3/4 filling as observed in the experiments.
A unique feature of the cytokine storm in coronavirus disease 2019 (COVID-19) is the dramatic elevation of interleukin 10 (IL-10). This was thought to be a negative feedback mechanism to suppress ...inflammation. However, several lines of clinical evidence suggest that dramatic early proinflammatory IL-10 elevation may play a pathological role in COVID-19 severity.
Electricity theft has been a growing concern for the smart grid. It can be defined as follows: illegal customers use energy from electric utilities without a contract or manipulate their meter ...readings to pay less or not pay the electricity bill. Over the past decade, significant studies have been done to prevent and combat theft. This article aims to provide a general overview of the progress of electricity theft detection, including threat models, datasets and input features adopted, methodologies and techniques, and evaluation metrics. We also make a performance comparison for each detection method. Finally, the challenges and future research directions are presented in this article.
The phase-locked loop (PLL)-caused couplings on the grid-connected converter (GCC) are strengthened by increasing its bandwidth and then incur synchronization instability. This article proposes a ...constant-coupling-effect-based PLL (CCE-PLL) to resolve the aforementioned issues. Initially, the feature of the PLL-caused couplings on GCC is explored. It exhibits that the couplings are varied along with the PLL bandwidth hence jeopardizing the system's stability. Subsequently, the CCE-PLL with a constant and low coupling regardless of its bandwidth on the GCC is proposed. It illustrates that the CCE-PLL bandwidth does not influence the GCC's impedance response, bringing the GCC and CCE-PLL can be designed separately. Last, the experiments confirm that using CCE-PLL, the system has high robustness against grid impedance variation, and the GCC is capable of injecting/absorbing 1.0 per unit active power in a very weak grid. Moreover, the system attains good anti-interference ability and transient performance under system disturbances thanks to the permission usage of the high CCE-PLL bandwidth.
Enhancing health intervention for floating populations has become an essential aspect of public health around the world. China launched a policy reform aimed at implementing immediate reimbursement ...for trans-provincial inpatient treatments. The objective of this study was to investigate the effects of this policy change on socioeconomic inequality in health among the floating population.
This study used two waves of individual-level data from the China Migrants Dynamic Survey (CMDS) collected in 2017 and 2018 as well as administrative hospital data at the city level. The sample included 122061 individuals and 262 cities. Under a quasi-experimental research design, we built up the framework to employ the generalized and multi-period difference-in-differences estimation strategy. We used the number of qualified hospitals that could provide immediate reimbursement to represent the degree and intensity of the implementation of this policy change. We also calculated the Wagstaff Index (WI) to measure socioeconomic inequality in health.
This policy change and income level had a negative joint impact on the health status of floating population (odds ratio = 0.955, P < 0.01), that is, the lower the income, the better the number of qualified hospitals' effect on health improvement. Furthermore, as the number of qualified tertiary hospitals increased, the health inequality would decrease significantly on average at the city level (P < 0.05). In addition, inpatient utilization as well as total expenditure and reimbursement significantly improved after the policy change, and the magnitude of increase was greater in the relatively lower-income group (P < 0.01). Finally, only inpatient spending could obtain immediate reimbursement in the early stage, thus, compared with primary care, these impacts were greater in tertiary care.
Our study revealed that after the implementation of immediate reimbursement, the floating population could obtain greater and more timely reimbursement, which significantly increased its inpatient utilization, promoted health, and reduced the health inequality caused by socioeconomic factors. These results suggest that a more accessible and friendly medical insurance scheme should be promoted for this group.
Following the discovery of the quantum Hall effect1, 2 and topological insulators3, 4, the topological properties of classical waves began to draw attention5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, ...17, 18, 19, 20, 21. Topologically non-trivial bands characterized by non-zero Chern numbers are realized through either the breaking of time-reversal symmetry using an external magnetic field5, 6, 7, 15, 16 or dynamic modulation8, 17. Owing to the absence of a Faraday-like effect, the breaking of time-reversal symmetry in an acoustic system is commonly realized with moving background fluids20, 22, which drastically increases the engineering complexity. Here we show that we can realize effective inversion symmetry breaking and create an effective gauge flux in a reduced two-dimensional system by engineering interlayer couplings, achieving an acoustic analogue of the topological Haldane model2, 23. We show that the synthetic gauge flux is closely related to Weyl points24, 25, 26 in the three-dimensional band structure and the system supports chiral edge states for fixed values of kz.
Studies of Late Quaternary geological slip-rates and the GPS decadal slip-rates along the major strike-slip faults in the northern margin of the Tibetan Plateau show that slip-rates remain relatively ...constant along the middle sections of each fault and decrease rapidly toward the ends. Our recent studies suggest that the slip rates are low (<10mm/yr) along the major strike-slip faults, i.e., Altyn-Tagh fault and Qilian-Haiyuan fault. West of 95°E, the slip rate on the Altyn-Tagh fault has been determined to be 8–12mm/yr, and gradually decreases from 95°E eastward to about 1–2mm/yr at the easternmost segment of the fault. The slip-rate of Qilian-Haiyuan fault is about 1–2mm/yr near the Halahu Lake, near the western tip of the fault, then increases to a relatively constant value of 4–5mm/yr in the Qilian area (101°E and eastward). Eastward, the fault merges into the NS trending Liupan Shan fault zone east of Haiyuan, and the slip rate drops to 1–3mm/yr, or even lower. Our present observations on the variation and distribution of slip rates along the major strike slip faults indicate that slip on the Altyn-Tagh fault is mainly dissipated through internal deformation, by thrust faulting within the Qilian Shan and shortening within the adjacent Cenozoic basins. Left-lateral strike-slip on the Qilian-Haiyuan fault might be transformed into shortening and growth of the Liupan Shan to the east, and may also contribute partially to the deformation in the western Qilian Shan. In conclusion, the distribution of slip rates from both late Quaternary geological records and the current GPS observations suggest a decrease in slip rate, a redistribution of strain, and the transformation of displacement along the major strike slip faults into crustal shortening, basin formation and mountain uplift that characterize present-day deformation of the northern margin of the Tibetan Plateau.
►Slip rates of faults are jointly determined by geological and geodetic methods. ►Boundary faults of northern Tibet slip at very low rate of less than 10mm/a. ►Sharp tapers of slip rate are found at the ends of these boundary faults. ►Slips on boundary faults are dissipated by thrust faulting and basin shortening. ►Present-day deformation of north Tibet margin is featured by this dissipation.
The laurel family within the Magnoliids has attracted attentions owing to its scents, variable inflorescences, and controversial phylogenetic position. Here, we present a chromosome-level assembly of ...the Litsea cubeba genome, together with low-coverage genomic and transcriptomic data for many other Lauraceae. Phylogenomic analyses show phylogenetic discordance at the position of Magnoliids, suggesting incomplete lineage sorting during the divergence of monocots, eudicots, and Magnoliids. An ancient whole-genome duplication (WGD) event occurred just before the divergence of Laurales and Magnoliales; subsequently, independent WGDs occurred almost simultaneously in the three Lauralean lineages. The phylogenetic relationships within Lauraceae correspond to the divergence of inflorescences, as evidenced by the phylogeny of FUWA, a conserved gene involved in determining panicle architecture in Lauraceae. Monoterpene synthases responsible for production of specific volatile compounds in Lauraceae are functionally verified. Our work sheds light on the evolution of the Lauraceae, the genetic basis for floral evolution and specific scents.
Aims
This study aims to compare estimates of primary liver cancer mortality from World Health Organization (WHO), Global Burden Disease (GBD) and Global Cancer Observatory (GCO).
Methods
Liver cancer ...mortality was extracted from WHO, GBD and GCO for 92 countries for the most recent year. Age‐standardized rate (ASR) was computed and used for current comparisons across the three data sources. Temporal trend for 75 countries was analysed and compared between WHO and GBD from 1990 to 2019 using joinpoint regression. Average annual percentage change for the most recent 10 years was used as indicator for change.
Results
The estimates of ASR were quite consistent across the three data sources, but most similar estimates were found between WHO and GCO in both region and country levels. The differences in ASR were negatively correlated with completeness of cause‐of‐death registration, human development index and proportion of liver cancer because of alcohol consumption. Consistent trends of ASR were found from 35 countries between WHO and GBD in the most recent 10 years. However, opposite trends were found from 10 countries with five from Southern America, four from Europe and one from Asia. Of the 18 countries for projection, opposite trends between WHO and GBD were found from seven countries.
Conclusion
While the ASR of primary liver cancer mortality was comparable across the three data sources, most similar estimates were found between WHO and GCO. The opposite trends found from 10 countries between WHO and GBD raised concerns of true patterns in these countries.
Lay summary
To date, the global estimates of primary liver cancer mortality have been provided by World Health Organization, Global Burden Disease, and Global Cancer Observatory, yet no study has compared the current estimates of primary liver cancer mortality from different data sources globally. This study aims to compare the most recent estimates of primary liver cancer mortality from 92 countries across these three sources. The comparisons were also made through the temporal trend analysis from 1990 to 2019, and the projection to 2030 between WHO and GBD. While the estimates of primary liver cancer mortality were comparable across the three data sources for 92 countries, most similar estimates were found between WHO and GCO. Opposite trends in the most recent 10 years were identified from five Southern American countries (Colombia, Cuba, Dominican Republic, Jamaica and Mexico), four European countries (Latvia, Sweden, Cyprus and Poland) and one Asian country (Uzbekistan).
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