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Abstract Road traffic accidents are the leading causes of injuries and fatalities. Understanding the traffic accident occurrence pattern and its contributing factors are prerequisites for effective traffic safety management. The paper proposes a deep learning approach for traffic accident recognition and information extraction from online Chinese news to extract and organize traffic accidents automatically. The approach consists of three modules, including automated news collection, news classification, and traffic accident information extraction. The automated news collection module crawls news from online sources, cleans and organizes it into a general news database with different categories of news. The news classification module robustly recognizes the traffic accident news from all types of news by fusing the sentence‐wise and context‐wise semantic news information. The accident information extraction module extracts the key attributes of traffic accidents (e.g. causes, times, locations) from news text using the SoftLexicon‐BiLSTM‐CRF method. The proposed approach is validated by comparing it with state‐of‐the‐art text mining methods using Chinese news data crawled online. The results show that the approach can achieve a high information extraction performance in terms of precision, recall, and F1‐score. It improves the performance of the best benchmark model (BiLSTM‐CRF) by 18.8% in precision and 12.08% in F1‐score. In addition, the potential value of the automatically extracted accident data is illustrated from online news in complementing traditional authority accident data to drive more effective traffic safety management in practice.

Abstract In response to the challenge of telomere attrition during DNA replication, cancer cells predominantly employ telomerase or, in 10–15% of cases, the alternative lengthening of telomeres (ALT). The intricate details of ALT, however, remain elusive. In this study, we unveil that the knockdown of lamina-associated polypeptide 2 alpha (LAP2α) in ALT cells results in telomere dysfunction, triggering a notable increase in ALT-associated hallmarks, including high frequencies of PML bodies (APBs), C-rich extrachromosomal circles (C-circles), and telomere sister chromatid exchange (T-SCE). Furthermore, LAP2α emerges as a crucial player in break-induced telomere replication for telomerase-positive cells following telomeric double-strand breaks. Mechanistically, our investigation suggests that LAP2α may influence the regulation of the heterochromatic state of telomeres, thereby affecting telomeric accessibility. In line with our findings, LAP2α expression is markedly reduced in ALT-positive osteosarcoma. And the use of methotrexate (MTX) can restore the heterochromatin state altered by LAP2α depletion. This is evidenced by a significant inhibition of tumor proliferation in ALT-positive patient-derived xenograft (PDX) mouse models. These results indicate the important role of LAP2α in regulating ALT activity and offer insights into the interplay between lamina-associated proteins and telomeres in maintaining telomere length. Importantly, our findings may help identify a more appropriate target population for the osteosarcoma therapeutic drug, MTX.

The dc-link voltage oscillation caused by the negative impedance characteristic of the constant power load is a significant issue in the series LC branch-permanent magnet synchronous motor (PMSM) cascade system. To this end, this paper proposes a voltage prediction compensation (VPC) strategy to suppress the dc-link voltage oscillation by adding a voltage stability constraint term to the finite control set model predictive current control (FCS-MPCC). First, the linearized q-axis reference voltage is obtained by taking the derivation of the cost function of the VPC, thereby deriving the input impedance of the inverter-permanent magnet motor system. Then, the impedance matching criterion and Nyquist stability criterion are used to theoretically prove that the proposed strategy can effectively improve system stability, and the robustness of the proposed method to changes in motor parameters is analyzed. Finally, experimental verification was conducted on a 1 kW motor platform. The results show that when the motor is running under rated working conditions, after adding the stability constraint, the dc-link voltage fluctuation drops from 40 V to 7 V; the q-axis current pulsation rate also drops to 3.8 %. Theoretical analysis and experimental results show that the VPC strategy can effectively suppress the dc-link voltage oscillation of the cascade drive system.

Polyurethane concrete has excellent mechanical properties, rapid solidification and durability, but brittle damage is easy to occur at room temperature. To solve the problem of insufficient bending toughness of polyurethane concrete, steel fibers were added into the traditional polyurethane concrete to prepare steel fiber polyurethane concrete in this paper. A total of 8 test beams with dimensions of 150 mm × 150 mm × 550 mm were made. The influence of steel fibers with different length-diameter ratios and volume ratios on the flexural strength of polyurethane concrete was studied through four points bending tests. The results show that under the same volume ratio and diameter, as the length of steel fiber increases from 30 mm to 60 mm, the peak load decreased by 8.6%, and the displacement corresponding to the peak load decreased by 41.1%. Under the same length-diameter ratio, the steel fiber volume ratio from 0.5% to 2.0%, the peak load increased by 49.1%, and the displacement corresponding to the peak load increased by 100.8%. The toughening degree, relative initial flexural toughness ratio and relative residual flexural toughness ratio were proposed, and the inconsistencies of calculation criteria for flexural toughness in steel fiber reinforced concrete (JG/T 472–2015) were optimized.

The warm shed method is commonly employed in concrete construction during winter as an effective technique. This study aims to investigate the impact of different sizes and heating methods on the temperature inside the shed and the concrete through scale model testing. The hot air heating method is simulated using finite element software, and a prediction model is developed. The findings reveal an inverse relationship between the size of the warm shed and its heat preservation effect. When utilizing hot air, both the maximum temperature inside the warm shed and at the center of the concrete increase by 15.5 °C and 25.2 °C respectively compared to when employing a point heat source, resulting in earlier stabilization times of 390 min and 1000 min respectively, as well as a more uniform temperature distribution across all parts. Based on finite element simulation results, an optimal wind speed μ is proposed along with a corresponding prediction model.

ABSTRACT Objective: The study aims to explore the relationship between lipoprotein lipase (LPL) variants and hyperlipidemic acute pancreatitis (HLAP) in the southeastern Chinese population. Subjects and methods: In total, 80 participants were involved in this study (54 patients with HLAP and 26 controls). All coding regions and intron-exon boundaries of the LPL gene were sequenced. The correlations between variants and phenotypes were also analysed. Results: The rate of rare LPL variants in the HLAP group is 14.81% (8 of 54), higher than in controls. Among the detected four variants (rs3735959, rs371282890, rs761886494 and rs761265900), the most common variant was rs371282890. Further analysis demonstrated that subjects with rs371282890 "GC" genotype had a 2.843-fold higher risk for HLAP (odds ratio [OR]: 2.843, 95% confidence interval [CI]: 1.119-7.225, p = 0.028) than subjects with the "CC" genotype. After adjusting for sex, the association remained significant (adjusted OR: 3.083, 95% CI: 1.208-7.869, p = 0.018). Subjects with rs371282890 "GC" genotype also exhibited significantly elevated total cholesterol, triglyceride and non-high-density lipoprotein cholesterol levels in all the participants and the HLAP group (p < 0.05). Conclusion: Detecting rare variants in LPL might be valuable for identifying higher-risk patients with HLAP and guiding future individualised therapeutic strategies.

The relationship between biodegraded oil and its source has long been a complex and contentious topic. The Western Halaalate area is located in the Piedmont area on the northwest margin of the Junggar Basin. Source rocks of the Fengcheng Formation exist both locally and in the nearby Mahu Depression. In order to determine the source of biodegraded crude oil in this area, the molecular marker characteristics of biodegraded crude oil were analyzed by gas chromatography-mass spectrometry. The results showed that the vitrinite reflectance (Ro) of source rocks of the Permian Fengcheng Formation in the nearby Mahu Depression is greater than 1.3% and has entered a high mature stage of condensate oil and moisture gas; the source rock of Permian Fengcheng Formation in Western Halaalate area is in a mature stage with Ro of 0.79%~1.13%. The ascending configuration of tricyclic terpenes C20-C21-C23 for the crude oil samples found in the Carboniferous strata of the Western Halaalate Area is consistent with the characteristics of the Fengcheng Formation source rocks, which are present in both the Western Halaalate Area and the nearby Mahu Depression. Chromatography spectrometry examination shows that crude oils have undergone a varying degree of biodegradation. The Carboniferous oil was originated from the in situ Fengcheng Formation source rocks based on the application of molecular markers resistant to biodegradation, such as maturity parameters, salinity parameters, the new gammacerane index, and aromatic hydrocarbon parameters, combined with the analysis of hydrocarbon migration pathway. In addition, the oil biodegradation alteration rules in the Western Halaalate area were clarified, which advances regional knowledge of the relationship between biodegraded oil and source rocks.

The vibration of concrete is a typical concealed construction process, in which mature supervisory methods are lacking. The quality of vibration relies heavily on the subjective experience and sense of responsibility of the vibration operators. For the widely used hand-held concrete vibrators, existing methods for monitoring the quality of vibration primarily focus on the horizontal positioning of the vibrator. Due to the limited measurable range of vibration depth, these methods are inapplicable for monitoring the vibration depth during the vibration of deeper structures such as walls, columns, and large volumes of concrete. This paper makes the initial attempt to address the issue of monitoring concrete vibration depth, presenting a method that broadens the measurable range of depth in vibration monitoring. Inspired by the principles of optical and magnetic scales, this paper introduces a radio frequency identification (RFID) scales positioning system for the real-time monitoring of vibration depth. The proposed RFID scales vibration depth monitoring method theoretically has no upper limit on the measurable vibration depth, rendering it applicable to monitoring vibration depth of any extent. By comparing the positioning accuracy of different RFID scales hardware compositions, the optimal RFID scales hardware composition and the most effective RFID scales positioning algorithm were identified. The feasibility and accuracy of the vibration depth monitoring method based on RFID scales were validated through engineering field application. This method achieves centimeter-level accuracy in monitoring vibration depth, offers a tool for the precise control of vibration depth, and helps avoid potential quality issues in vibration.

Repetitive control (RC) has been widely used in many fields due to its excellent ability to suppress periodic disturbances. However, when the permanent magnet synchronous motor (PMSM) operates at variable speeds, the speed loop sampling frequency is usually not equal to an integer multiple of the fundamental frequency of speed ripple, which prevents disturbances from being completely suppressed. In addition, the open-loop gain of the motor control system with RC is too large at certain frequencies, resulting in excessive speed overshoot during startup and loading. To solve these two problems, this paper proposes a fractional order repetitive control (FORC) strategy with dynamically adjustable gain. A fractional order delay link is introduced to make up for the shortcomings of the conventional repetitive controller (CRC) in its ability to suppress periodic speed ripples when the sampling frequency is not an integer multiple of the fundamental frequency of the motor. Then, to weaken the speed overshoot caused by RC, a nonlinear function fal(e,α,δ) is added in the front of the FORC to dynamically adjust the FORC gain. Simulation and experimental results verify the effectiveness of the proposed method.

This paper proposes a new method for compensating current measurement errors in shipboard permanent magnet propulsion motors. The method utilizes cascade decoupling second-order generalized integrators (SOGIs) and adaptive linear neurons (ADALINEs) as the current harmonic extractor and the compensator, respectively. It can compensate for the dq-axes offset and scaling errors simultaneously, improving phase current distortion while reducing the ripples of motor speed and torque. Compared to the traditional motor model-based compensation strategies, the proposed method is robust against the changes in motor parameters with the online adaptive capability of the ADALINE algorithm. Furthermore, due to the good real-time performance of SOGIs and ADALINEs, the proposed compensation strategy can effectively operate in both the steady state and transient state of the motor. Finally, the effectiveness of the proposed method is verified through the physical and hardware-in-the-loop (HIL) experiments. After compensating for the current measurement errors of a 1 kW test motor with the propeller-characteristics load, the torque ripple and speed ripple are reduced by more than 65% and 80%, respectively. At the same time, the DC component and the second-order and third-order harmonics in the phase currents are also significantly reduced. Similar test results can be also obtained on the HIL platform with a 100 kW permanent magnet motor.