A novel surface-mounted magnetic screw mechanism (SMMSM) with large output torque and high magnetic energy utilization is proposed. To study the torque-displacement characteristics, the analytical model of SMMSM is derived based on the equivalent magnetic charge theory, virtual displacement method and superposition principle. The influence of the spiral angle of SMMSM, number of magnetic bar, thickness of magnetic bar, and thickness of air gap on the torque are explored, and key structural parameters are selected to design and manufacture the prototype. A static and dynamic experimental platform is built, and the experiment show that the maximum output torque of the SMMSM can reach 1.185 N m at a displacement of 1 mm, and the step response time is 27.5 ms, which are substantially superior to the existing maglev couplings. Finally, the SMMSM is applied to 2D flow valve. The experiments show that the SMMSM-based 2D flow valve has the advantages of large flow rate, high system pressure and fast dynamic response: the maximum flow rate is 167.8 L/min at a system pressure of 25 MPa, the step response time is 16.5 ms, and the amplitude-frequency width is 46.0 Hz, which is also superior to the existing maglev 2D flow valves in terms of these performance indexes. The research indicates the SMMSM-based 2D flow valve can be used as a potential solution for electro-hydraulic servo-proportional valves.

The microwave window unit is the core component of the electron cyclotron heating and current drive (EC H CD) system used in fusion reactors. In this work, a diamond disk for the microwave window was designed according to the electromagnetic propagation theory. Then, the finite element method was employed to build a microwave window model based on our tailored dimension. The effect of brazing and subsequent service processes on the stress/strain distributions and electrical parameters were explored. Overall, the microwave window exhibited excellent performance, with the maximum principal stress of the brazed disk under service being 51 MPa, which was much lower than the allowable stress of diamond. It was also indicated that the electrical properties barely changed, which could satisfy functional requirements. This work provided theoretical guidance for the design and manufacture of diamond microwave windows used in fusion reactors.

AbstractA model-free adaptive robust control based on time delay estimation (TDE) is proposed for robot in the presence of disturbance and input saturation. TDE is utilized to estimate the complicated nonlinear terms of the robot including unknown dynamics and disturbance, and a TDE error observer is developed to estimate the inevitable TDE error. When the input torque of the robot exceeds the upper or lower limit of the input saturation, an auxiliary system and a saturation deviation boundary adaptive law are employed to mitigate the negative impact of input saturation on the position tracking. Finally, the robust control law is obtained by backstepping. The stability of the closed-loop system is proved by Lyapunov functions, and the validity of the proposed method is demonstrated by comparative simulations and experiments. Compared with the model-based controllers and other model-free controllers, the proposed method does not necessitate the accurate dynamic model of the complicated system and with lower computation. Moreover, it can guarantee the desired position tracking performance of the robot even subject to disturbance and input saturation simultaneously.

Si has been regarded as a hopeful advanced anode of lithium-ion batteries due to its features such as ultrahigh theoretical specific capacity and high natural abundance. But, it suffers from electrochemical irreversibility because of large volumetric change and poor conductivity during cycle. In spite of obtaining enhanced lithium storage performance after compositing with carbon materials, most of the reported Si/C composite anodes lack a simple preparation process. For the new anode materials, the simple preparation process is as important as showing high performance. Herein, an efficient simple method is developed to prepare a composite of N-doped carbon embedding Si nanoparticles (Si@C) to response to the above Si faced challenges. Its preparation process just consists of very simple ball milling and pyrolysis carbonization, showing great simplicity. The findings confirm that the combination of the ball-milling mixing and the use of PVP carbon precursor enables the optimal Si@C-2 composite to have a N-doped carbon embedding structure and a robust interface Si-O-C chemical bond bonding, hence obtaining enhanced conductivity, high electrochemical kinetics and superb structure stability during cycling process. Therefore, the Si@C-2 anode exhibits excellent performance, with 1542 and 794.7 mA h g-1 after 100 and 1000 cycles at 100 and 1000 mA g-1, respectively, superior to many reported Si/C composites. The simple, scalable preparation method and superb performances offer Si@C-2 great promising in advanced LIB anode applications.

A novel full circumferential reluctance maglev coupling (FCRMC) is proposed in this paper, which not only meets the requirements of force transmission and valve position feedback of two-dimensional (2D) valve but also has the advantages of closed -loop magnetic circuit and high magnetic energy utilization rate. To investigate the torque -displacement characteristic of FCRMC, a detailed analytical model based on the equivalent magnetic circuit method is formulated, which considers the leakage flux effect, edge effect, and magnetic permeability nonlinearity. The effects of the inclination angle, width, air gap, and number of teeth on the torque are explored by the analytical model, and appropriate structural parameters are selected to design and manufacture the prototype. A dedicated test bench is built and the static/dynamic characteristics of FCRMC are tested. The experimental results show that the FCRMC prototype has a step velocity of 20.8 x 10-3 mm/ms, a torque -volume ratio of 8.47 x 10-3 N m/cm3, a torque -permanent magnets(PMs) volume ratio of 0.050 N m/cm3, and a step velocity-PMs volume ratio of 2.63 x 10-3 mm/ms & sdot;cm3. Finally, to verify the feasibility of the FCRMC in real work situations, the FCRMC is applied to a 2D electro-hydraulic proportional flow valve. The experimental results show that, at 15 MPa, the no-load flow of the valve is 82.4L/min, with a hysteresis of 3.8 %, a step velocity of 17.5 x 10-3 mm/ms, and amplitude and phase frequency widths of 22.4 Hz and 26.5 Hz.

Autonomous driving is one of the high technology for the application of AI large models. The technical framework includes perception, prediction, and vehicle control. An appropriate number of multi-sensor combinations can provide more comprehensive, accurate and decision-making capabilities. Whether it is urban NOA or AVP (Automated Valet Parking), multi-source data fusion technology is needed, involving cameras, lidars, radars, ultrasonic sensors, etc. However, the key factor affecting multi-source data fusion is the weight distribution problem. The target motion attributes output by multiple sensors when detecting the same target at different positions are different, especially the accuracy of the target at the edge of the FOV (field of view) is significantly reduced. In order to solve this problem, this paper proposes a multi-sensor dynamic weight distribution algorithm with improved Kalman filtering. The influence factors of the algorithm in this paper consider the longitudinal distance and the circumferential angle, and the reliability of the theoretical model is verified by numerical simulation results, which can provide an important reference for the fusion technology of radars, lidars and ultrasonic radars. In addition, based on the dynamic weight distribution algorithm, this paper also gives a dynamic effective detection area, which can improve the early warning measurement when the moving target enters the area, and also effectively improves the safety factor of autonomous driving, which provides a new theoretical model for the realization of intelligent transportation and the realization of more advanced autonomous driving.

This paper presents for the first time the seismic analysis of a half-space containing a water-filled valley under 2D oblique P- and SV-waves by the finite-infinite element (FE-IFE) method. The equivalent seismic forces for the Chi-Chi Earthquake on the near-field boundary are calculated based on the exact free-field response. The effect of water-filled valleys on the seismic response of the half-space is a problem not well treated previously, which is considered through the soil-liquid interface in this paper. The present analysis procedure including the soil-liquid coupling is verified against Luco et al. for a half-space with an empty semi-circular canyon. New findings of this paper include: (1) The horizontal acceleration is amplified on the "near" side (to incident waves) of the valley, which is higher for filled valleys under P-waves, but decayed by the filled valley under SV-waves. (2) The effect of overlying water body on vertical acceleration is less significant for SV- than for P-waves. (3) For SV-waves with overly critical angles, the horizontal acceleration is larger for the "far" than "near" side, and larger difference exists for deeper filled valleys, coupled by amplified vertical acceleration. Additional observations were made for the numerical analysis inside the text.

For the fabrication of diamond microwave windows, a solid joining of diamond with copper rings is critically required. In this work, the AgCu-mSn-nTi filler alloys were designed to braze the diamond and copper. The typical joint microstructure was characterized and its formation mechanism was unveiled. The effect of Ti or Sn fraction on the microstructure and joint shear strength was examined. Finally, an inherent relationship between the microstructure and joint bond strength was clarified. The joint average shear strength optimized reached 256.1 MPa when brazed using AgCu-10Sn-1Ti. With more Ti addition, excessive CuSn3Ti5 compounds produced early failure in the interlayer. Increasing Sn content helped to densify the interlayer. However, rigid Cu5Sn formed declined the joint strength when Sn was over 15 wt%. The work performed provided an optimized filler composition for low-temperature joining of diamond and copper and would guide the fabrication of diamond windows theoretically and technologically.

Retraction: Wang L, Huang W, Zhang S, Liu Z. Complex image denoising framework with CNN-wavelet under concurrency scenarios for informatics systems.J Concurrency Computat: Pract Exper. 2021; 33-12. The above article, published online on 13 Nov 2018 Wiley Online Library (https://onlinelibrary.wiley.com/doi/full/10.1002/cpe.5059) has been retracted by agreement between the journal Editor, Professor David W. Walker, School of Computer Science and Informatics, Cardiff University, Cardiff CF24 3AA, UK and Wiley Periodicals, LLC. The retraction has been agreed following an investigation based on allegations raised by a third party. Several inconsistencies were found, including general logical flaws and irrelevant citations, making the motivation and conclusions of the article untrustworthy. The editorial office did not receive a response from the authors, and so requested underlying experimental data was not available for evaluation. Accordingly, the editors consider the conclusions of this manuscript invalid.

Background: For metastatic colorectal cancer (mCRC), the efficacy of third-line or above treatments is not ideal. Combining targeted vascular endothelial growth factor (VEGF) or vascular endothelial growth factor receptor (VEGFR) biological agents with chemotherapy or anti-programmed death receptor 1 (PD-1) treatment can bring longer survival benefits to patients with mCRC compared with the application of a single drug. In this study, fruquintinib was used as the research drug, and the main purpose was to compare the efficacy and safety of fruquintinib in combination with sintilimab (FS) or trifluridine and tipiracil (TAS-102) (FT) in the third-line or above treatment in mCRC patients.Methods: Based on real-world clinical practice, mCRC patients who progressed after second-line or higher-line chemotherapy regimens and received FS or FT as third-line or above treatment from December 2020 to November 2022 were analyzed. Progression-free survival (PFS) was the primary endpoint. Safety, disease control rate (DCR) and objective response rate (ORR) were secondary end points.Results: In the FS group, 47 patients received FS, and in the FT group, 45 patients received FT. The DCR values in the FS and FT groups were 80.9% (38/47) and 55.6% (25/45), respectively (P<0.05). The median PFS (mPFS) in the FS group was 6.0 months, and the mPFS in the FT group was 3.5 months (P<0.05). Most adverse events (AEs) were grade 1-2 in severity.Conclusions: As a third-line or above regimen in mCRC patients, compared to FT, treatment with FS provides a higher DCR and longer mPFS and is better tolerated. The combination of fruquintinib and sintilimab may become a new treatment option for mCRC patients.

Current robot path planning methods only consider local obstacle avoidance, and there are conflicts between global planning path and local planning path, resulting in the planned path is not global optimal and the planning efficiency of the method is low. In order to solve the above problems, the autonomous global path planning method of substation remote patrol robot is studied. After establishing the kinematic plane model of the remote patrol robot, the kinematic relation of the robot in space is determined according to the coordinate relation. Artificial potential field is introduced to calculate the initial heuristic information of ant colony algorithm, and the left and right planning path is obtained by bidirectional search. Experimental results show that the average path planning time of the proposed method is 22.92ms, and the number of robot collisions is significantly reduced, which effectively ensures the safety of patrol work.

In service life, the premature destruction mechanism and durability of reinforced concrete (RC) structures are mainly governed either by mechanical or environmental loads or by combined ones. These damages can strongly affect the water transport in concrete which may lead to more serious deterioration. This paper presented an experimental investigation on the coupling action of different uniaxial compressive stress levels ( $$\lambda _{c}$$ = 0, 0.6, 0.7, 0.8) and freeze-thaw cycles (0, 50, 100, 150, 200, 250 and 300 cycles), following by capillary water absorption tests. The residual strain was measured by strain gauges to evaluate the damage evolution of concrete. Moreover, the cumulative water content and sorptivity of specimens under the coupling action were recorded at a given time of exposure through an improved water absorption test set-up. The results show that concrete specimens with fly ash (15% by cement) exhibit better frost and water penetration resistance than ordinary concrete. The frozen samples with applying 60% ultimate load (0.6fc) have the best water penetration resistance in comparison with that samples are applied 0, 0.7 and 0.8, which is consistent with the result that under uniaxial compressive load only. Residual strain derived from strain-temperature curves indicates the deterioration of concrete is a continued accumulated and irreversible damage process. The distribution of water content and wetting front of penetration depth are remarkably influenced by the stress levels and freeze-thaw cycles (FTCs). The test data of cumulative water content confirms that FTCs play a relatively important role in the water absorption of concrete under the coupling action. In addition, an effectively theoretical method for predicting water absorption of concrete damaged under the coupling action of uniaxial compressive load and FTCs was developed in terms of the sorptivity. These conclusions presented in this paper will be helpful to better understand the degradation mechanism of frost resistance for RC structures after subjected to uniaxial compressive loading in coastal regions.

Social relations are closely related to each of us and are a crucial part of society. Recognizing the social relationships of people in pictures can improve AI’s understanding of human behavior, thereby facilitating collaborative interactions between computers and humans. Previous work only focused on a single picture, so too little information can be obtained. In this paper, we proposed Picture Reasoning Model(PRM) to achieve relationship classification, which innovatively uses the self-attention method to learn the association between relationships. The association between relationships is at the social level, thus using it to assist relationship recognition can get rid of the problem of insufficient information in a single picture. In addition, the model also adopts a two-stream approach, extracting both characters and global features for getting multiple perspectives information. We conduct extensive experiments on two benchmark datasets PIPA and PISC. Experimental results show that our model has improved the accuracy metric of the datasets compared with SOTA. On the PIPA dataset, the accuracy increases from 64.4% to 65.6%, and on the PISC dataset, the mAP raises from 72.7% to 73.2%, which validates the effectiveness of our proposals.

In order to improve compliance in human–robot interaction, a sensorless variable impedance control method is proposed. Variable impedance control is constructed using the end-effector velocity and the human–robot interaction force. Then, the impedance parameters are adjusted online to make the end-effector velocity more compliant with human behavior. Next, a velocity controller is designed to stabilize the end-effector velocity, and a compensation force is designed to avoid the measurement of the interaction force. Based on the velocity controller and the compensation force, an integrated controller is constructed to achieve stable end-effector velocity while compensating the interaction force online. The Lyapunov theory proves that with the sensorless variable impedance control, the system is stable, and the velocity tracking is bounded; simulation results demonstrate its feasibility. The sensorless variable impedance control can achieve more stable velocity and better compliance in human–robot interaction.

The risk of road accidents is rising rapidly. Distracted driving remains one of the leading causes of traffic accidents. Therefore, the identifying of the distracted driving become significant. Extensive methods based on the convolutional neural network (CNN) have been applied to the detection of the distracted driving. Within Convolutional Neural Network (CNN), the convolution operations are good at extracting local features but experience difficulty to capture global representations. Within visual transformer (ViT), the cascaded self-attention modules perform surpassingly in capturing content-based global interactions but unfortunately deteriorate local feature details. In order to address those challenges mentioned before, we propose a new distracted driving detection method that utilizes the driver and related object cues as guidance and combines CNN with ViT as a backbone to capture the local and global features. Besides, the simulation module is introduced to obtain the result of classification during a certain time period in the stage of inference. Under the widely used StateFarm benchmark, our proposed method presents the best performance.

This paper addresses the communication congestion and actuator fault in a nonlinear networked control system. A weighted average event-triggered mechanism adopted the weighted average of data packets is proposed to alleviate the communication congestion and save the network communication resources. Meanwhile, based on the system state estimation and fault estimation obtained by a state-fault observer, a fault-tolerant controller is designed to compensate and reduce the influence of fault and nonlinear factors in the networked control systems. The stability of the closed-loop system is proved by the Lyapunov–Kroasovskii theory, and the gains of the observer and controller are obtained by linear matrix inequalities. The feasibility of the proposed scheme is verified by the networked motor control system. The proposed weighted average event-triggered fault-tolerant control scheme can reduce the data transmission without affecting system performance. Meanwhile, it not only has fault-tolerant control performance but also reduces the influence of nonlinear factors on the system output.

The dynamic response characteristics of an earth-rock fill dam on a deep overburden are the focus of seismic research. In particular, evaluating the influence of the earthquake safety of the dam. A dynamic response analysis of earth-rock fill dam on a deep overburden based on viscoelastic boundary conditions was used to study the influence of boundary conditions (including fixed boundary conditions and viscoelastic boundary conditions). The results show that the fixed boundary condition greatly improves the dynamic response level of the dam during an earthquake and has no obvious influence on the distribution of the acceleration response in the dam and the foundation. The difference in the calculation results under the two boundary conditions is related to the seismic input characteristics and dynamic deformation characteristics of the soil material. An analysis of the acceleration response spectrum shows that the influence of the boundary conditions on the calculation results is limited to the magnitude level of the acceleration response, while the spectral characteristics of the vibration of the dam and the foundation do not have a significant impact.

A novel process for groove forming using electromagnetic field-assisted laser machining was studied using a high power diode laser (HPDL) to machine grooves into a 316L stainless steel substrate. The effect of directional Lorentz force generated by electromagnetic field on the discharge of the molten metal in laser processing is investigated and the corresponding experiment is carried out. First, based on the orthogonal experiment, the effects of laser power, scanning speed, magnetic field intensity and current density on the groove forming are analysed qualitatively. Then the Box-Behnken experimental scheme is used to supplement the experimental samples, and the back propagation (BP) neural network is applied to establish the quantitative computation model of process parameters and groove morphology characteristics. The experimental results reveal that scanning speed and laser power have greater influence on the groove depth, scanning speed and magnetic field intensity have larger influence on the upper groove width, and scanning power and laser power have greater influence on the lower groove width. The process parameter model based on BP neural network can conveniently analyse the electromagnetic field-assisted laser groove forming process.

加权平均电流(weighted average current,WAC)控制方法由于其环路降阶特性,在并网逆变器系统中得到了广泛的应用.然而,传统WAC控制方法并未充分考虑数字控制延时对并网逆变器系统造成的影响.该文分析表明,数字控制延时引入的相位滞后导致传统WAC控制方法不再具备环路降阶特性,而使得环路增益中出现一个随电网阻抗变化的反向谐振峰,使并网系统存在失稳的风险.针对此问题,该文提出一种基于超前补偿器的高鲁棒性WAC控制策略,该策略利用前馈通道中引入的超前补偿器来补偿反向谐振峰频率范围内的相位滞后,以此来实现环路降阶特性及弱电网适应性.对比分析和实验研究表明,所提控制策略能够保留传统WAC控制的降阶优点,同时对弱电网亦有很强的适应能力.