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Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls
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作者 Yang Shi Mingjun Wu +14 位作者 Shengbo Ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期98-134,共37页
Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and... Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass materials.These materials offer numerous advantages such as being lightweight,porous,and hierarchical.Due to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding materials.Despite concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding materials.In particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be valuable.The preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and analyzed.The composite methods and fillers of various biomass materials were reviewed.this paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field. 展开更多
关键词 Biomass materials Electromagnetic interference shielding Micro-nano structure interface control CONDUCTIVITY
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Association of the glycemic background patterns and the diabetes management efficacy in poorly controlled type 2 diabetes
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作者 Ayşe N Erbakan Müzeyyen Arslan Bahadır +6 位作者 FatoşN Kaya Büşra Güleç MiraçVural Keskinler Ümmügülsüm AktemurÇelik Özge Faydalıel Banu Mesçi Aytekin Oğuz 《World Journal of Diabetes》 SCIE 2025年第1期74-90,共17页
BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of ... BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of intensive and supportive glycemic management strategies over a 12-month period in individuals with T2DM with glycated hemoglobin(HbA1c)≥10%and varying backgrounds of glycemic control.METHODS This prospective observational study investigated glycemic control in patients with poorly controlled T2DM over 12 months.Participants were categorized into four groups based on prior glycemic history:Newly diagnosed,previously well controlled with recent worsening,previously off-target but now worsening,and HbA1c consistently above 10%.HbA1c levels were monitored quarterly,and patients received medical,educational,and dietary support as needed.The analysis focused on the success rates of good glycemic control and the associated factors within each group.RESULTS The study showed significant improvements in HbA1c levels in all participants.The most significant improvement was observed in individuals newly diagnosed with diabetes:65%achieved an HbA1c target of≤7%.The results varied between participants with different glycemic control histories,followed by decreasing success rates:39%in participants with previously good glycemic control,21%in participants whose glycemic control had deteriorated compared to before,and only 10%in participants with persistently poor control,with mean HbA1c levels of 6.3%,7.7%,8.2%,and 9.7%,respectively.After one year,65.2%of the“newly diagnosed patients”,39.3%in the“previously controlled group”,21.9%in the“previously off-target but now worsened'”group and 10%in the“poorly controlled from the start”group had achieved HbA1c levels of 7 and below.CONCLUSION In poorly controlled diabetes,the rate at which treatment goals are achieved is associated with the glycemic background characteristics,emphasizing the need for tailored strategies.Therefore,different and comprehensive treatment approaches are needed for patients with persistent uncontrolled diabetes. 展开更多
关键词 Type 2 diabetes mellitus Glycated hemoglobin Glycemic control Patient-centered care Diabetes management glycemic background
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Passive activity enhances residual control ability in patients with complete spinal cord injury
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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NURBS CURVE INTERPOLATOR WITH ADAPTIVE ACCELERATION-DECELERATION CONTROL 被引量:2
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作者 刘凯 赵东标 陆永华 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第4期241-247,共7页
The feedrate profile of non-uniform rational B-spline (NURBS) interpolation due to the contour errors is analyzed. A NURBS curve interpolator with adaptive acceleration-deceleration control is presented. In interpo-... The feedrate profile of non-uniform rational B-spline (NURBS) interpolation due to the contour errors is analyzed. A NURBS curve interpolator with adaptive acceleration-deceleration control is presented. In interpo- lation preprocessing, the sensitive zones of feedrate variations are processed with acceleration-deceleration control. By using the proposed algorithm, the machining accuracy is guaranteed and the feedrate is adaptively adjusted to he smoothed. The mechanical shock imposed in the servo system is avoided by the first and the second time derivatives of feedrates. A simulation of NURBS interpolation is given to demonstrate the validity and the effectiveness of the algorithm. The proposed interpolator can also be applied to the trajectory planning of the other parametric curves. 展开更多
关键词 numerical control systems INTERPOLATION adaptive algorithms NURBS curve interpolator adaptive acceleration and deceleration limited jerk
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Research on cubic polynomial acceleration and deceleration control model for high speed NC machining 被引量:10
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作者 Hong-bin LENG Yi-jie WU Xiao-hong PAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第3期358-365,共8页
To satisfy the need of high speed NC (numerical control) machining, an acceleration and deceleration (acc/dec) control model is proposed, and the speed curve is also constructed by the cubic polynomial. The proposed c... To satisfy the need of high speed NC (numerical control) machining, an acceleration and deceleration (acc/dec) control model is proposed, and the speed curve is also constructed by the cubic polynomial. The proposed control model provides continuity of acceleration, which avoids the intense vibration in high speed NC machining. Based on the discrete characteristic of the data sampling interpolation, the acc/dec control discrete mathematical model is also set up and the discrete expression of the theoretical deceleration length is obtained furthermore. Aiming at the question of hardly predetermining the deceleration point in acc/dec control before interpolation, the adaptive acc/dec control algorithm is deduced from the expressions of the theoretical deceleration length. The experimental result proves that the acc/dec control model has the characteristic of easy implementation, stable movement and low impact. The model has been applied in multi-axes high speed micro fabrication machining successfully. 展开更多
关键词 High speed NC machining acceleration and deceleration (acc/dec) control model Cubic speed curve Discrete mathematical model Adaptive acceleration and deceleration control algorithm
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Torque-based Optimal Acceleration Control for Electric Vehicle 被引量:1
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作者 LU Dongbin OUYANG Minggao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期319-330,共12页
The existing research of the acceleration control mainly focuses on an optimization of the velocity trajectory with respect to a criterion formulation that weights acceleration time and fuel consumption. The minimum-f... The existing research of the acceleration control mainly focuses on an optimization of the velocity trajectory with respect to a criterion formulation that weights acceleration time and fuel consumption. The minimum-fuel acceleration problem in conventional vehicle has been solved by Pontryagin's maximum principle and dynamic programming algorithm, respectively. The acceleration control with minimum energy consumption for battery electric vehicle(EV) has not been reported. In this paper, the permanent magnet synchronous motor(PMSM) is controlled by the field oriented control(FOC) method and the electric drive system for the EV(including the PMSM, the inverter and the battery) is modeled to favor over a detailed consumption map. The analytical algorithm is proposed to analyze the optimal acceleration control and the optimal torque versus speed curve in the acceleration process is obtained. Considering the acceleration time, a penalty function is introduced to realize a fast vehicle speed tracking. The optimal acceleration control is also addressed with dynamic programming(DP). This method can solve the optimal acceleration problem with precise time constraint, but it consumes a large amount of computation time. The EV used in simulation and experiment is a four-wheel hub motor drive electric vehicle. The simulation and experimental results show that the required battery energy has little difference between the acceleration control solved by analytical algorithm and that solved by DP, and is greatly reduced comparing with the constant pedal opening acceleration. The proposed analytical and DP algorithms can minimize the energy consumption in EV's acceleration process and the analytical algorithm is easy to be implemented in real-time control. 展开更多
关键词 permanent magnet synchronous motor(PMSM) field oriented control(FOC) efficiency model electric vehicle energy optimal acceleration
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Acceleration feedback control (AFC) enhanced by disturbance observation and compensation (DOC) for high precision tracking in telescope systems 被引量:3
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作者 Qiang Wang Hua-Xiang Cai +8 位作者 Yong-Mei Huang Liang Ge Tao Tang Yan-Rui Su Xiang Liu Jin-Ying Li Dong He Sheng-Ping Du Yu Ling 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第8期51-60,共10页
Abstract In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observa- tion and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Teles... Abstract In this paper, a cascade acceleration feedback control (AFC) enhanced by a disturbance observa- tion and compensation (DOC) method is proposed to improve the tracking precision of telescope systems. Telescope systems usually suffer some uncertain disturbances, such as wind load, nonlinear friction and other unknown disturbances. To ensure tracking precision, an acceleration feedback loop which can in- crease the stiffness of such a system is introduced. Moreover, to further improve the tracking precision, we introduce the DOC method which can accurately estimate the disturbance and compensate it. Furthermore, the analysis of tracking accuracy used by this method is proposed. Finally, a few comparative experimental results show that the proposed control method has excellent performance for reducing the tracking error of a telescope system. 展开更多
关键词 telescopes -- instrumentation control method - instrumentation miscellaneous high angularresolution - instrumentation detector -- control software
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Deformation,fragmentation and acceleration of a controlled fragmentation charge casing 被引量:1
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作者 Andreas Helte Olof Andersson Patrik Lundberg 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第5期786-795,共10页
Two different finite element software,LS-DYNA and Impetus,have been evaluated to test their ability to predict the deformation,fragmentation and acceleration of a controlled fragmentation charge casing.The general-pur... Two different finite element software,LS-DYNA and Impetus,have been evaluated to test their ability to predict the deformation,fragmentation and acceleration of a controlled fragmentation charge casing.The general-purpose program LS-DYNA was used with a multi-material ALE formulation and a masspreserving erosion criterion coupled to a Johnson-Cook fracture criterion.In the Impetus simulations,a third order Lagrangian element formulation was used for the casing and a node-splitting element erosion treatment coupled to a Cockcroft-Latham failure criterion was used to describe casing fracture.The high-explosive gases were described by a discrete particle formalism.In order to acquire data to validate our computational tools and constitutive models,a series of experiments have been performed using a laboratory charge with an internal grooved casing.In the test series,the charge geometry was fixed except that the groove depth were varied from very shallow to very deep resulting in different deformation patterns,fracture modes and terminal velocities.Various diagnostic tools captured the different stages of the expansion and fragmentation of the casing.A high-speed framing camera depicted the deformation pattern before fragmentation and was used to determine the moment when the casing failed.Three different complementary techniques were used to follow the acceleration of the fragments;a Photon Doppler velocimetry to determine the initial acceleration of the casing,double exposed radiographs to estimate the fragment velocity after break-up and a high-speed video to determine the terminal velocity of the fragment after leaving the fireball.In addition,the fragments were soft recovered in a set of sawdust pit tests and their final shape and weight were measured.A SEM was used to characterise the fracture surfaces and to determine the modus of fracture(tensile or shear failure).Comparisons to experiments show that both software can predict the change in deformation behaviour when the groove depth increases,from tangential necking for shallow grooves to radial punching for deep groves.Both software could also reasonable well predict the acceleration of the fragments,though both overestimates the terminal velocity for the charge with the deepest grooves. 展开更多
关键词 controlLED FRAGMENTATION Fracture MECHANICS LS-DYNA Impetus
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Fuzzy sliding mode control guidance law with terminal impact angle and acceleration constraints 被引量:6
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作者 Qingchun Li Wensheng Zhang +1 位作者 Gang Han Yuan Xie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期664-679,共16页
In this paper, a novel fuzzy sliding mode control(FSMC) guidance law with terminal constraints of miss distance, impact angle and acceleration is presented for a constant speed missile against the stationary or slow... In this paper, a novel fuzzy sliding mode control(FSMC) guidance law with terminal constraints of miss distance, impact angle and acceleration is presented for a constant speed missile against the stationary or slowly moving target. The proposed guidance law combines the sliding mode control algorithm with a fuzzy logic control scheme for the lag-free system and the first-order lag system. Through using Lyapunov stability theory, we prove the sliding surface converges to zero in finite time. Furthermore, considering the uncertain information and system disturbances, the guidance gains are on-line optimized by fuzzy logic technique. Numerical simulations are performed to demonstrate the performance of the FSMC guidance law and the results illustrate the validity and effectiveness of the proposed guidance law. 展开更多
关键词 guidance law sliding mode control fuzzy logic impact angle
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Acceleration Feedback Enhanced H_∞Disturbance Attenuation Control for a Class of Nonlinear Underactuated Vehicle Systems 被引量:3
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作者 HE Yu-Qing HAN Jian-Da 《自动化学报》 EI CSCD 北大核心 2008年第5期558-564,共7页
在这篇论文,一个概括加速反馈控制(声频抗流圈) 设计方法,命名声频抗流圈提高了 H ∞控制器,为两个被建议完整激活并且在激活的非线性的自治车辆系统下面。声频抗流圈基于已知的动力学作为柔韧的改进被设计到正常控制。首先,以便拒... 在这篇论文,一个概括加速反馈控制(声频抗流圈) 设计方法,命名声频抗流圈提高了 H ∞控制器,为两个被建议完整激活并且在激活的非线性的自治车辆系统下面。声频抗流圈基于已知的动力学作为柔韧的改进被设计到正常控制。首先,以便拒绝不确定性和外部骚乱,线性 prefilter 在新声频抗流圈设计方法被使用在正常声频抗流圈代替高获得。然后,背走算法被用于 AFC 设计在激活的系统下面。两个的分析在有限获得 L2 稳定性显示出的频率领域和输入产量的骚乱变细新控制器设计方法是适用的。最后,模拟关于无人的模型直升飞机的追踪的控制被进行。结果与没有声频抗流圈,追踪的控制获得验证新方法的可行性的那些相比。 展开更多
关键词 干扰弱化 加速反馈控制 非线性H∞控制 自动控制系统
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Acceleration feedback of a current-following synchronized control algorithm for telescope elevation axis 被引量:1
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作者 Tao Tang Tong Zhang +2 位作者 Jun-Feng Du Ge Ren Jing Tian 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第11期7-12,共6页
This paper proposes a dual-motor configuration to enhance closed-loop performance of a telescope control system. Two identical motors are mounted on each side of a U-type frame to drive the telescope elevation axis in... This paper proposes a dual-motor configuration to enhance closed-loop performance of a telescope control system. Two identical motors are mounted on each side of a U-type frame to drive the telescope elevation axis instead of a single motor drive, which is usually used in a classical design. This new configuration and mechanism can reduce the motor to half the size used in the former design, and it also provides some other advantages. A master-slave current control mode is employed to synchronize the two motors. Acceleration feedback control is utilized to further enhance the servo performance. Extensive experiments are used to validate the effectiveness of the proposed control algorithm in synchronization, disturbance attenuation and low-velocity tracking. 展开更多
关键词 telescopes -- instrumentation: control method-- instrumentation miscellaneous: high angularresolution -- instrumentation: detector -- control software
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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:4
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作者 Ding Wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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The acceleration of a high-charge electron bunch to 10 GeV in a 10-cm nanoparticle-assisted wakefield accelerator 被引量:1
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作者 Constantin Aniculaesei Thanh Ha +24 位作者 Samuel Yoffe Lance Labun Stephen Milton Edward McCary Michael M.Spinks Hernan J.Quevedo Ou Z.Labun Ritwik Sain Andrea Hannasch Rafal Zgadzaj Isabella Pagano Jose A.Franco-Altamirano Martin L.Ringuette Erhart Gaul Scott V.Luedtke Ganesh Tiwari Bernhard Ersfeld Enrico Brunetti Hartmut Ruhl Todd Ditmire Sandra Bruce Michael E.Donovan Michael C.Downer Dino A.Jaroszynski Bjorn Manuel Hegelich 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第1期15-24,共10页
An intense laser pulse focused onto a plasma can excite nonlinear plasma waves.Under appropriate conditions,electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic vel... An intense laser pulse focused onto a plasma can excite nonlinear plasma waves.Under appropriate conditions,electrons from the background plasma are trapped in the plasma wave and accelerated to ultra-relativistic velocities.This scheme is called a laser wakefield accelerator.In this work,we present results from a laser wakefield acceleration experiment using a petawatt-class laser to excite the wakefields as well as nanoparticles to assist the injection of electrons into the accelerating phase of the wakefields.We find that a 10-cm-long,nanoparticle-assisted laser wakefield accelerator can generate 340 pC,10±1.86 GeV electron bunches with a 3.4 GeV rms convolved energy spread and a 0.9 mrad rms divergence.It can also produce bunches with lower energies in the 4–6 GeV range. 展开更多
关键词 acceleration NANOPARTICLE CHARGE
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Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer 被引量:1
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作者 Chi Ma Dianbiao Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1039-1050,共12页
This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eli... This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the system.In addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader agent.To address this problem,a neural network state observer based on the leader state information is designed.Then,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite time.Finally,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm. 展开更多
关键词 Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control
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Exhaustive review of acceleration strategies for Monte Carlo simulations in photon transit 被引量:1
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作者 Louzhe Xu Zijie Zhu Ting Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第5期5-21,共17页
Monte Carlo simulation techniques have become the quintessence and a pivotal nexus of inquiry in the realm of simulating photon movement within biological fabrics.Through the stochastic sampling of tissue archetypes d... Monte Carlo simulation techniques have become the quintessence and a pivotal nexus of inquiry in the realm of simulating photon movement within biological fabrics.Through the stochastic sampling of tissue archetypes delineated by explicit optical characteristics,Monte Carlo simulations possess the theoretical capacity to render unparalleled accuracy in the depiction of exceedingly intricate phenomena.Nonetheless,the quintessential challenge associated with Monte Carlo simulation methodologies resides in their extended computational duration,which significantly impedes the refinement of their precision.Consequently,this discourse is specifically dedicated to exploring innovations in strategies and technologies aimed at expediting Monte Carlo simulations.It delves into the foundational concepts of various acceleration tactics,evaluates these strategies concerning their speed,accuracy,and practicality,and amalgamates a comprehensive overview and critique of acceleration methodologies for Monte Carlo simulations.Ultimately,the discourse envisages prospective trajectories for the employment of Monte Carlo techniques within the domain of tissue optics. 展开更多
关键词 Medical optics photon transport simulation Monte Carlo simulation acceleration
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Controlled transition to different proton acceleration regimes:Near-critical-density plasmas driven by circularly polarized few-cycle pulses
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作者 Shivani Choudhary De Marco Sudipta Mondal +1 位作者 Daniele Margarone Subhendu Kahaly 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第5期1-18,共18页
A controlled transition between two different ion acceleration mechanisms would pave the way to achieving different ion energies and spectral features within the same experimental set up,depending on the region of ope... A controlled transition between two different ion acceleration mechanisms would pave the way to achieving different ion energies and spectral features within the same experimental set up,depending on the region of operation.Based on numerical simulations conducted over a wide range of experimentally achievable parameter space,reported here is a comprehensive investigation of the different facets of ion acceleration by relativistically intense circularly polarized laser pulses interacting with thin near-critical-density plasma targets.The results show that the plasma thickness,exponential density gradient,and laser frequency chirp can be controlled to switch the interaction from the transparent operating regime to the opaque one,thereby enabling the choice of a Maxwellian-like ion energy distribution with a cutoff energy in the relativistically transparent regime or a quasi-monoenergetic spectrum in the opaque regime.Next,it is established that a multispecies target configuration can be used effectively for optimal generation of quasi-monoenergetic ion bunches of a desired species.Finally,the feasibility is demonstrated for generating monoenergetic proton beams with energy peak atℰ≈20–40 MeV and a narrow energy spread ofΔℰ/ℰ≈18%–28.6%confined within a divergence angle of∼175 mrad at a reasonable laser peak intensity of I0≃5.4×10^(20)W/cm^(2). 展开更多
关键词 acceleration REGIME CIRCULAR
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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances 被引量:1
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作者 ZHOU Li WANG Guo-rong WAN Min 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期271-284,共14页
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control... An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller. 展开更多
关键词 adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control
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Current protocol to achieve dental movement acceleration and pain control with Photo-biomodulation
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作者 Angela Dominguez 《World Journal of Methodology》 2023年第5期379-383,共5页
When designing a study on dental movement acceleration or pain control during orthodontic treatment,it is crucial to consider effective parameters.The objective of this editorial is to compile the most effective param... When designing a study on dental movement acceleration or pain control during orthodontic treatment,it is crucial to consider effective parameters.The objective of this editorial is to compile the most effective parameters supported by evidence that should be considered in future studies to achieve complete parameter homogenization.The protocol currently recommended to homogenize the parameters and facilitate the development of further meta-analysis in terms of acceleration of movement and pain control in orthodontics is Wavelength:810 nm,2.2 J per surface,0.1 W in continuous mode/0.1 W average power in a superpulsed,sweeping movement,1mm from the mucosa,22 seconds along the vestibular surface and 22 seconds along the lingual surface,the recommended speed of movement is 2 mm/sec,1 application during each orthodontic control,to achieve dental movement acceleration and repeat the dose at 24 h to ensure pain elimination.The energy density and power density will depend on the spot size used in the equipment and the distance from the mucosa.It will strengthen the evidence of photobiomodulation as the best therapy to accelerate tooth movement and at the same time control the pain produced by orthodontic treatments. 展开更多
关键词 PHOTOBIOMODULATION Laser-assisted orthodontics Dental movement acceleration Pain control Diode laser
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Control of highly pathogenic avian influenza through vaccination 被引量:1
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作者 Xianying Zeng Jianzhong Shi Hualan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1447-1453,共7页
The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian in... The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus. 展开更多
关键词 avian influenza control highly pathogenic VACCINATION
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