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In order to analyze the loss, temperature rise and the mechanical structural response under the combined magnetic tension and thermal stress of the stator core, the electromagnetic-temperature-stress coupling calculation for the stator core of a synchronous generator is carried out in this paper. Firstly, the core loss and the magnetic pull per unit area are theoretically deduced, followed by an analysis of the core's temperature rise characteristics. On this basis, the mechanical structure response of the core under the coupling excitation of magnetic pull and non-uniform thermal load is obtained. Then, a three-dimensional finite element model of the CS-5 synchronous generator is established. This model calculates the magnetic pull per unit area, loss curve and temperature distribution of the stator core. Furthermore, the deformation, strain and stress of the stator core under the simultaneous action of magnetic tension and thermal load are obtained. The results show that the stator slot temperature is highest when the generator runs stably. The deformation at the groove is largest and the stress at the bottom of the groove is higher. Finally, the temperature rises of the end face, inside slot and outside circle of the stator core are monitored in real-time by thermocouples and a temperature monitor. The measured temperature distribution of the stator core is in good agreement with the finite element simulation results, verifying the effectiveness of the electromagnetic-temperature-stress coupling method. In this paper, the temperature distribution of the stator core and the mechanical structural response distribution of the stator core under magnetic and thermal coupling excitation are obtained, providing a technical reference for the reverse optimization design of the generator structure and the prevention of stator core deformation.

Based on the official criminal data released by the Tokyo Metropolitan Police Department in 2019, this paper discusses the temporal-spatial distribution of various types of crimes in the special wards of Tokyo. The results show that: ① The times of high and low incidence of different types of crime differ significantly. Although vicious crime and violent crime present no obvious monthly distribution, property crime clearly differs between the first and second half of a calendar year. ② The month before the new year sees a surge in most types of crime. ③ Vicious crime peaks in the hours between night and early morning. Violent crime and property crime correlate positively with the frequency of human interaction and peak in the morning and evening commuting hours. ④ The spatial distribution of crime resembles the concentric circles of the three rings of the special wards of Tokyo, with a central high-incidence area, a center-peripheral low-incidence area, and a marginal high-incidence area. In addition, the center sees more personal crime than the periphery, whereas property crimes show the opposite trend. ⑤ A spatial autocorrelation analysis shows that the special wards of Tokyo may be grouped into the “high-high” and “low-low” agglomeration modes of different types of crime, with marked differences between the various types of crime. The crime can be divided into three types: central agglomeration, double central agglomeration, and decentralized agglomeration.

Cable conduits are crucial for urban power transmission and distribution systems. However, current conduit robots are often large and susceptible to tilting issues, which hampers the effective and intelligent inspection of these conduits. Therefore, there is an urgent need to develop a smaller-sized conduit inspection robot to address these challenges. Based on an in-depth analysis of the characteristics of the cable conduit working environment and the associated functional requirements, this study successfully developed a small-scale urban cable conduit inspection robot prototype. This development was grounded in relevant design theories, simulation analyses, and experimental tests. The test results demonstrate that the robot's bracing module effectively prevents tilting within the conduit. Additionally, the detection module enables comprehensive 360-degree conduit inspections, and the vacuuming module meets the negative pressure requirements for efficient absorption of dust and foreign matter. The robot has met the expected design goals, effectively enhanced the automation of the cable conduit construction process, and improved the quality control of cable laying. [ABSTRACT FROM AUTHOR]

Background: Usage of immune checkpoint inhibitors (ICIs) has prolonged the overall survival (OS) of patients with extensive‐stage small‐cell lung cancer (ES‐SCLC). In clinical trials, males accounted for a large proportion, leading to the uncertainty of its efficacy in female patients. We therefore conducted this study to explore the efficacy and safety of using ICIs in female patients with ES‐SCLC. Methods: We retrospectively enrolled female SCLC patients and subdivided them into two groups. Group A (n = 40) was defined as ES‐SCLC patients who received first‐line standard chemotherapy with or without ICIs. Group B (n = 47) included relapsed SCLC patients who were administered with second‐line therapies. Kaplan–Meier methodology was used to calculate survival analysis. Chi‐squared tests were used to analyze the incidence of adverse events (AEs). Results: Median progression‐free survival (PFS) and median OS favored the ICI‐contained cohorts (Group A PFS: 8.3 vs. 6.1 months; OS: not reached vs. 11.3 months; Group B PFS: 15.1 vs. 3.3 months; OS: 35.3 vs. 8.3 months), especially in those patients who received second‐line immunotherapies. Patients who received immunotherapy had a slightly higher incidence rate of grade ≥3 AEs (Group A: 71.4% vs. 46.2%; Group B: 44.5% vs. 13.2%). Those who developed grade ≥3 AEs in first‐line ICIs cohort had a more favorable survival (PFS: 8.3 vs. 3.2 months; OS: not reached vs. 5.1 months). Conclusions: Our study suggested that female ES‐SCLC patients treated with immunotherapy tended to achieve a relatively longer survival. The incidence of AEs (grade ≥3) was higher in women patients receiving ICIs, which requires monitoring more closely. [ABSTRACT FROM AUTHOR]

High-precision time–frequency is widely used in time measurement, satellite navigation, scientific research, and other fields. With the rapid development of optical clock technology, the fractional frequency instability and uncertainty of optical clock have reached 10−18 orders of magnitude, which is expected to contribute to generating the International Atomic Time and may even be used to redefine the "second" in the future. Therefore, the long-distance transfer of time–frequency signals between optical atomic clocks is of great significance. Free-space optical frequency transfer technology is one of the important technologies for solving the space-based optical clock comparison because of its high transfer precision and easy networking characteristics. In order to solve the long-distance space-based optical clock comparison, this paper investigates a free-space active phase noise compensation method using an Acousto-Optic Modulator (AOM), based on the traditional optical fiber phase noise compensation scheme. This new method is more flexible and scalable than the optical fiber time–frequency transfer technology. The optical frequency transfer over a 64 m free-space link is demonstrated. The fractional frequency transfer instability during free running is 9.50 × 10−16 at 1 s, and 4.44 × 10−16 at 2000 s, and the fractional frequency instability after compensation is 7.10 × 10−17 at 1 s, 3.07 × 10−19 at 2000 s, which is about 1–3 orders of magnitude better than that in free running, and provides a feasible scheme for space-based optical clock comparison. [ABSTRACT FROM AUTHOR]

Numerous policies have been implemented to advance the growth of renewable energy. Nonetheless, certain policies have not yielded the anticipated impact on the progression of renewable energy development. In order to maximize the promotion effect of renewable energy policies, this study proposes a capacity allocation optimization method of wind power generation, solar power and energy storage in power grid planning under different policy objectives. First, based on the policy quantification, grey relation analysis (GRA) is used to calculate the correlation degree of the policy indicators on the planning capacity of renewable energy. Further, a multi‐objective capacity estimation model for wind, solar and energy storage is comprehensively presented. Some highly correlated policy indicators are transformed into the special constraints. And the economy and the stability of the power grid are integrated as the objective function. Meanwhile, the carbon trading and punishment for wind power and solar power abandonment are considered. Finally, the proposed model is solved by NSGA‐II‐PSO (particle swarm optimization) algorithm. The novelty of the algorithm is that the crossover operation of NSGA‐II is replaced by the position updating of particle swarm. The calculation result of the case study can effectively evaluate the optimal planning capacity of renewable energy under different policies, while ensuring the economic and the stability of the power system. The study can provide the reasonable basis and the valid analytical method for the policy formulation and the renewable energy development. [ABSTRACT FROM AUTHOR]