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Fault-observer-based iterative learning model predictive controller for trajectory tracking of hypersonic vehicles
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作者 CUI Peng GAO Changsheng AN Ruoming 《Journal of Systems Engineering and Electronics》 2025年第3期803-813,共11页
This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hype... This work proposes the application of an iterative learning model predictive control(ILMPC)approach based on an adaptive fault observer(FOBILMPC)for fault-tolerant control and trajectory tracking in air-breathing hypersonic vehicles.In order to increase the control amount,this online control legislation makes use of model predictive control(MPC)that is based on the concept of iterative learning control(ILC).By using offline data to decrease the linearized model’s faults,the strategy may effectively increase the robustness of the control system and guarantee that disturbances can be suppressed.An adaptive fault observer is created based on the suggested ILMPC approach in order to enhance overall fault tolerance by estimating and compensating for actuator disturbance and fault degree.During the derivation process,a linearized model of longitudinal dynamics is established.The suggested ILMPC approach is likely to be used in the design of hypersonic vehicle control systems since numerical simulations have demonstrated that it can decrease tracking error and speed up convergence when compared to the offline controller. 展开更多
关键词 hypersonic vehicle actuator fault tracking control iterative learning control(ILC) model predictive control(MPC) fault observer
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Fixed-time Target-guided Coordinate Control of Unmanned Surface Vehicles Based on Dynamic Surface Control
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作者 LI Chao−yi XU Hai−xiang +2 位作者 YU Wen−zhao DU Zhe DING Ya−nan 《船舶力学》 北大核心 2025年第6期849-862,共14页
This paper presents an investigation on the target-guided coordinated control(TACC)of unmanned surface vehicles(USVs).In the scenario of tracking non-cooperative targets,the status information of the target can only b... This paper presents an investigation on the target-guided coordinated control(TACC)of unmanned surface vehicles(USVs).In the scenario of tracking non-cooperative targets,the status information of the target can only be obtained by some USVs.In order to achieve semi-encirclement tracking of noncooperative targets under maritime security conditions,a fixed-time tracking control method based on dynamic surface control(DSC)is proposed in this paper.Firstly,a novel TACC architecture with decoupled kinematic control law and decoupled kinetic control law was designed to reduce the complexity of control system design.Secondly,the proposed DSC-based target-guided kinematic control law including tracking points pre-allocation strategy and sigmoid artificial potential functions(SigAPFs)can avoid collisions during tracking process and optimize kinematic control output.Finally,a fixed-time TACC system was proposed to achieve fast convergence of kinematic and kinetics errors.The effectiveness of the proposed TACC approach in improving target tracking safety and reducing control output chattering was verified by simulation comparison results. 展开更多
关键词 unmanned surface vehicle distributed control target-guided coordinate control fixed-time convergence dynamic surface control
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Observed-based adaptive neural tracking control for nonlinear systems with unknown control directions and input delay
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作者 DENG Yuxuan WANG Qingling 《Journal of Systems Engineering and Electronics》 2025年第1期269-279,共11页
Enhancing the stability and performance of practical control systems in the presence of nonlinearity,time delay,and uncertainty remains a significant challenge.Particularly,a class of strict-feedback nonlinear uncerta... Enhancing the stability and performance of practical control systems in the presence of nonlinearity,time delay,and uncertainty remains a significant challenge.Particularly,a class of strict-feedback nonlinear uncertain systems characterized by unknown control directions and time-varying input delay lacks comprehensive solutions.In this paper,we propose an observerbased adaptive tracking controller to address this gap.Neural networks are utilized to handle uncertainty,and a unique coordinate transformation is employed to untangle the coupling between input delay and unknown control directions.Subsequently,a new auxiliary signal counters the impact of time-varying input delay,while a Nussbaum function is introduced to solve the problem of unknown control directions.The leverage of an advanced dynamic surface control technique avoids the“complexity explosion”and reduces boundary layer errors.Synthesizing these techniques ensures that all the closed-loop signals are semi-globally uniformly ultimately bounded(SGUUB),and the tracking error converges to a small region around the origin by selecting suitable parameters.Simulation examples are provided to demonstrate the feasibility of the proposed approach. 展开更多
关键词 adaptive neural network dynamic surface control unknown control direction input delay
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Modeling and sliding mode control based on inverse compensation of piezo-positioning system
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作者 LI Zhi-bin XIN Yuan-ze +1 位作者 ZHANG Jian-qiang SUN Chong-shang 《中国光学(中英文)》 北大核心 2025年第1期170-185,共16页
In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis... In order to enhance the control performance of piezo-positioning system,the influence of hysteresis characteristics and its compensation method are studied.Hammerstein model is used to represent the dynamic hysteresis nonlinear characteristics of piezo-positioning actuator.The static nonlinear part and dynamic linear part of the Hammerstein model are represented by models obtained through the Prandtl-Ishlinskii(PI)model and Hankel matrix system identification method,respectively.This model demonstrates good generalization capability for typical input frequencies below 200 Hz.A sliding mode inverse compensation tracking control strategy based on P-I inverse model and integral augmentation is proposed.Experimental results show that compared with PID inverse compensation control and sliding mode control without inverse compensation,the sliding mode inverse compensation control has a more ideal step response and no overshoot,moreover,the settling time is only 6.2 ms.In the frequency domain,the system closed-loop tracking bandwidth reaches 119.9 Hz,and the disturbance rejection bandwidth reaches 86.2 Hz.The proposed control strategy can effectively compensate the hysteresis nonlinearity,and improve the tracking accuracy and antidisturbance capability of piezo-positioning system. 展开更多
关键词 piezo-positioning system hysteresis nonlinearity Hammerstein model Prandtl-Ishlinskii(P-I)model system identification sliding mode control
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Integrated Scheduling of Communication,Sensing,and Control for UAV-aided FSO Systems
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作者 LU Dingshan YU Yinchang +1 位作者 SU Daopeng WANG Jinyuan 《电讯技术》 北大核心 2025年第6期892-902,共11页
Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investig... Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investigate the integrated scheduling of communication,sensing,and control for UAV-aided FSO communication systems.Initially,a sensing-control model is established via the control theory.Moreover,an FSO communication channel model is established by considering the effects of atmospheric loss,atmospheric turbulence,geometrical loss,and angle-of-arrival fluctuation.Then,the relationship between the motion control of the UAV and radial displacement is obtained to link the control aspect and communication aspect.Assuming that the base station has instantaneous channel state information(CSI)or statistical CSI,the thresholds of the sensing-control pattern activation are designed,respectively.Finally,an integrated scheduling scheme for performing communication,sensing,and control is proposed.Numerical results indicate that,compared with conventional time-triggered scheme,the proposed integrated scheduling scheme obtains comparable communication and control performance,but reduces the sensing consumed power by 52.46%. 展开更多
关键词 FSO communications integrated scheduling of communication sensing and control unmanned aerial vehicle(UAV)
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Robust fixed-time flight controller for a dual-system convertible UAV in the cruise mode
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作者 Lulu Chen Zhenbao Liu +2 位作者 Qingqing Dang Wen Zhao Wenyu Chen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期53-66,共14页
This paper investigates the attitude tracking control problem for the cruise mode of a dual-system convertible unmanned aerial vehicle(UAV)in the presence of parameter uncertainties,unmodeled uncertainties and wind di... This paper investigates the attitude tracking control problem for the cruise mode of a dual-system convertible unmanned aerial vehicle(UAV)in the presence of parameter uncertainties,unmodeled uncertainties and wind disturbances.First,a fixed-time disturbance observer(FXDO)based on the bi-limit homogeneity theory is designed to estimate the lumped disturbance of the convertible UAV model.Then,a fixed-time integral sliding mode control(FXISMC)is combined with the FXDO to achieve strong robustness and chattering reduction.Bi-limit homogeneity theory and Lyapunov theory are applied to provide detailed proof of the fixed-time stability.Finally,numerical simulation experimental results verify the robustness of the proposed algorithm to model parameter uncertainties and wind disturbances.In addition,the proposed algorithm is deployed in a open-source UAV autopilot and its effectiveness is further demonstrated by hardware-in-the-loop experimental results. 展开更多
关键词 Convertible UAV Flight control Disturbance observer Fixed-time control
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Realizing high-speed target tracking by using multi-rate feedforward predictive control for the acquisition, tracking, and pointing system
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作者 Hang Li Gaoliang Peng +4 位作者 Xiaobiao Shan Mingyuan Zhao Wei Zhang Jinghan Wang Feng Cheng 《Defence Technology(防务技术)》 2025年第7期137-151,共15页
The acquisition,tracking,and pointing(ATP)system is widely used in target tracking,counter-UAV operations,and other related fields.As UAV technology develops,there is a growing demand to enhance the tracking capabilit... The acquisition,tracking,and pointing(ATP)system is widely used in target tracking,counter-UAV operations,and other related fields.As UAV technology develops,there is a growing demand to enhance the tracking capabilities of ATP systems.However,in practical applications,ATP systems face various design constraints and functional limitations,making it infeasible to indefinitely improve hardware performance to meet tracking requirements.As a result,tracking algorithms are required to execute increasingly complex tasks.This study introduces a multi-rate feedforward predictive controller to address issues such as low image feedback frequency and significant delays in ATP systems,which lead to tracking jitter,poor tracking performance,low precision,and target loss.At the same time,the pro-posed approach aims to improve the tracking capabilities of ATP systems for high-speed and highly maneuverable targets under conditions of low sampling feedback rates and high feedback delays.The method suggested is also characterized by its low order,fast response,and robustness to model parameter variations.In this study,an actual ATP system is built for target tracking test,and the proposed algorithm is fully validated in terms of simulation and actual system application verification.Results from both simulations and experiments demonstrate that the method effectively compensates for delays and low sampling rates.For targets with relative angular velocities ranging from 0 to 90°/s and angular accelerations between 0 and 470°/s^(2),the system improved tracking accuracy by 70.0%-89.9%at a sampling frequency of 50 Hz and a delay of 30 m s.Moreover,the compensation algorithm demonstrated consistent performance across actuators with varying characteristics,further confirming its robustness to model insensitivity.In summary,the proposed algorithm considerably enhances the tracking accuracy and capability of ATP systems for high-speed and highly maneuverable targets,reducing the probability of target loss from high speed.This approach offers a practical solution for future multi-target tracking across diverse operational scenarios. 展开更多
关键词 Multi-rate systems Predictive feedforward control Target tracking Laser weapon
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Formation-containment control for nonholonomic multi-agent systems with a desired trajectory constraint
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作者 GU Xueqiang LU Lina +1 位作者 XIANG Fengtao ZHANG Wanpeng 《Journal of Systems Engineering and Electronics》 2025年第1期256-268,共13页
This paper addresses the time-varying formation-containment(FC) problem for nonholonomic multi-agent systems with a desired trajectory constraint, where only the leaders can acquire information about the desired traje... This paper addresses the time-varying formation-containment(FC) problem for nonholonomic multi-agent systems with a desired trajectory constraint, where only the leaders can acquire information about the desired trajectory. Input the fixed time-varying formation template to the leader and start executing, this process also needs to track the desired trajectory, and the follower needs to converge to the convex hull that the leader crosses. Firstly, the dynamic models of nonholonomic systems are linearized to second-order dynamics. Then, based on the desired trajectory and formation template, the FC control protocols are proposed. Sufficient conditions to achieve FC are introduced and an algorithm is proposed to resolve the control parameters by solving an algebraic Riccati equation. The system is demonstrated to achieve FC, with the average position and velocity of the leaders converging asymptotically to the desired trajectory. Finally, the theoretical achievements are verified in simulations by a multi-agent system composed of virtual human individuals. 展开更多
关键词 multi-agent systems nonholonomic dynamics formation-containment(FC)control desired trajectory constrains
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Non-singular fast terminal sliding mode control for roll-pitch seeker based on extended state observers
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作者 XIAO Bowen XIA Qunli 《Journal of Systems Engineering and Electronics》 2025年第2期537-551,共15页
For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode contr... For air-to-air missiles, the terminal guidance’s preci-sion is directly contingent upon the tracking capabilities of the roll-pitch seeker. This paper presents a combined non-singular fast terminal sliding mode control method, aimed at resolving the frame control problem of roll-pitch seeker tracking high maneu-vering target. The sliding mode surface is structured around the principle of segmentation, which enables the control system’s rapid attainment of the zero point and ensure global fast conver-gence. The system’s state is more swiftly converged to the slid-ing mode surface through an improved adaptive fast dual power reaching law. Utilizing an extended state observer, the overall disturbance is both identified and compensated. The validation of the system’s stability and its convergence within a finite-time is grounded in Lyapunov’s stability criteria. The performance of the introduced control method is confirmed through roll-pitch seeker tracking control simulation. Data analysis reveals that newly proposed control technique significantly outperforms existing sliding mode control methods by rapidly converging the frame to the target angle, reduce the tracking error of the detec-tor for the target, and bolster tracking precision of the roll-pitch seeker huring disturbed conditions. 展开更多
关键词 air-to-air missile roll-pitch seeker finite-time con-vergence combined sliding mode control extended state observer
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Impact time control guidance for moving-target considering velocity variation and field-of-view constraint
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作者 YANG Hao ZHANG Shifeng +1 位作者 BAI Xibin YANG Chengye 《Journal of Systems Engineering and Electronics》 2025年第2期552-568,共17页
In the existing impact time control guidance (ITCG) laws for moving-targets, the effects of time-varying velocity caused by aerodynamics and gravity cannot be effectively con-sidered. Therefore, an ITCG with field-of-... In the existing impact time control guidance (ITCG) laws for moving-targets, the effects of time-varying velocity caused by aerodynamics and gravity cannot be effectively con-sidered. Therefore, an ITCG with field-of-view (FOV) constraints based on biased proportional navigation guidance (PNG) is developed in this paper. The remaining flight time (time-to-go) estimation method is derived considering aerodynamic force and gravity. The number of differential equations is reduced and the integration step is increased by changing the integral variable, which makes it possible to obtain time-to-go through integration. An impact time controller with FOV constraints is proposed by analyzing the influence of the biased term on time-to-go and FOV constraint. Then, numerical simulations are performed to verify the correctness and superiority of the method. 展开更多
关键词 moving target time-varying velocity time-to-go esti-mation field-of-view(FOV)constraint flight time control.
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A high maneuvering motion strategy and stable control method for tandem twin-rotor aerial-aquatic vehicles near the water surface
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作者 Sifan Wu Maosen Shao +4 位作者 Sihuan Wu Zhilin He Hui Wang Jinxiu Zhang Yuan Liu 《Defence Technology(防务技术)》 2025年第2期206-220,共15页
The maneuverability and stealth of aerial-aquatic vehicles(AAVs)is of significant importance for future integrated air-sea combat missions.To improve the maneuverability and stealth of AAVs near the water surface,this... The maneuverability and stealth of aerial-aquatic vehicles(AAVs)is of significant importance for future integrated air-sea combat missions.To improve the maneuverability and stealth of AAVs near the water surface,this paper proposed a high-maneuverability skipping motion strategy for the tandem twin-rotor AAV,inspired by the motion behavior of the flying fish to avoid aquatic and aerial predators near the water surface.The novel tandem twin-rotor AAV was employed as the research subject and a strategybased ADRC control method for validation,comparing it with a strategy-based PID control method.The results indicate that both control methods enable the designed AAV to achieve high stealth and maneuverability near the water surface with robust control stability.The strategy-based ADRC control method exhibits a certain advantage in controlling height,pitch angle,and reducing impact force.This motion strategy will offer an inspiring approach for the practical application of AAVs to some extent. 展开更多
关键词 Tandem twin-rotor Aerial-aquatic vehicle High maneuvering motion strategy Active disturbance rejection controller Skipping on water surface
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绵阳-长宁拉张槽东北缘埃迪卡拉系灯影组上部地层缺失及构造意义 被引量:1
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作者 丁一 刘树根 +9 位作者 文龙 马奎 陈代钊 宋金民 王瀚 王林康 陈明思 杨钹 唐攀 李智武 《地质学报》 北大核心 2025年第2期352-364,共13页
尽管绵阳-长宁拉张槽的油气地质意义已经得到广泛认可,其时空分布及成因机制自发现以来争议不断。在此背景下,本文对拉张槽北段东缘广元—宁强地区的震旦系(国际上称埃迪卡拉系)—寒武系过渡地层开展了系统的地层序列、岩相分析工作。... 尽管绵阳-长宁拉张槽的油气地质意义已经得到广泛认可,其时空分布及成因机制自发现以来争议不断。在此背景下,本文对拉张槽北段东缘广元—宁强地区的震旦系(国际上称埃迪卡拉系)—寒武系过渡地层开展了系统的地层序列、岩相分析工作。特征岩相及生物地层表明宽川铺、舒家坝、曹家坝—东山子地区普遍出现碑湾段下部甚至藻白云岩段上部与宽川铺组不整合接触,反映了高家山段和碑湾段的广泛缺失。该地层缺失区可以与川中—北斜坡地区连成一线。研究区灯影组以局限潮坪—潟湖环境的藻白云岩及泥晶白云岩沉积为主,而西侧的大滩—羊木地区灯影组截然变化为斜坡—盆地相硅质岩沉积,指示同沉积伸展断层的活动。这种相带突变样式在中扬子台地南缘和上扬子台地东缘也有发育,反映了整个中上扬子地区在震旦纪—寒武纪转折期总体处于伸展背景,广泛发育断控型碳酸盐岩台地边缘。绵阳-长宁拉张槽巨大的宽度(数十千米)、剥蚀厚度(数百米)及灯影组顶部长期的沉积间断(近20 Ma)说明其形成与差异升降作用有关,难以用岩溶地貌解释。考虑到研究区与川中—北斜坡的灯影组上段的缺失区总体呈线状分布,可用断层上盘的掀斜作用引起相对抬升来解释。伸展断层活动的高峰期大致可以约束在灯影组沉积晚期到麦地坪组沉积初期,对应灯影组上部到宽川铺组底部的广泛缺失。 展开更多
关键词 绵阳-长宁拉张槽 灯影组 地层缺失 伸展背景 断控
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基于TGA-IST-GC-MS协同TGA和GC-MS评价香料的热稳定性及香气释放特征 被引量:1
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作者 朱龙杰 王蕙婷 +6 位作者 吴昌健 张华 朱君 叶远青 曹毅 殷志琦 朱怀远 《食品科学》 北大核心 2025年第4期201-208,共8页
为更好地评估香料的热稳定性,提升香料的使用价值,通过热重分析-样品存储接口-气相色谱-质谱(thermogravimetric analysis-sample storage interface-gas chromatography-mass spectrometry,TGA-IST-GC-MS)联用法辅以TGA和GC-MS建立香... 为更好地评估香料的热稳定性,提升香料的使用价值,通过热重分析-样品存储接口-气相色谱-质谱(thermogravimetric analysis-sample storage interface-gas chromatography-mass spectrometry,TGA-IST-GC-MS)联用法辅以TGA和GC-MS建立香料热稳定性的统一评价方法。首先根据香料的挥发特性,利用TGA获得最佳进样温度,然后使用GC-MS和TGA-IST-GC-MS在不同体系下分别获得常规GC-MS图和TGA-GC-MS图,通过2种色谱图对比计算得到香料热稳定性的稳定度、裂解度和碎裂度3个重要指标,最后再依据热稳定性对香料加热前后的香气变化进行考察。结果表明:以香料挥发时的最大质量损失速率峰温度作为TGA-IST-GC-MS的最佳进样温度,方法具有较高的响应强度和较好的重复性;通过2种GC-MS图的对比,有效降低了香料基质背景的影响,提高了方法的准确性,使其对单体香料和多组分天然香料都具有较好的适用性;依据热稳定性的3个指标,可进一步掌握香料受热反应时的裂解强度和新裂解产物的生成量,对香气评价具有较好的实用性和指导性。 展开更多
关键词 热重分析-样品存储接口-气相色谱-质谱 香料 热稳定性 裂解产物 香气评价
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基于顶空-固相微萃取-气相色谱-质谱和顶空-气相色谱-离子迁移谱技术结合化学计量法分析芜菁冻干片挥发性成分 被引量:1
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作者 岳丽 张英仙 +4 位作者 祖力皮牙·买买提 王佳敏 毛红艳 于明 热依拉木·海力力 《食品与发酵工业》 北大核心 2025年第2期300-310,共11页
为探究不同品种芜菁冻干片中挥发性有机物(volatile organic compounds,VOCs)的差异,采用顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction gas chromatography-mass spectrometry,HS-SPME-GC-MS)和顶空-气相色谱... 为探究不同品种芜菁冻干片中挥发性有机物(volatile organic compounds,VOCs)的差异,采用顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction gas chromatography-mass spectrometry,HS-SPME-GC-MS)和顶空-气相色谱-离子迁移谱(headspace gas chromatography-ion mobility spectrometry,HS-GC-IMS)对紫色、黄色和白色3种芜菁冻干片的VOCs进行分析,并结合主成分分析(principal component analysis,PCA)和偏最小二乘判别法(partial least squares-discriminant analysis,PLS-DA)等化学计量法探究不同品种芜菁冻干片挥发性成分的差异。结果表明,通过HS-SPME-GC-MS共解析出96种VOCs,包括醛类、醇类、酮类、含硫化合物、酯类、酸类等化合物,其中含硫化合物和酯类为芜菁冻干片中相对含量最高的化合物种类;HS-GC-IMS共解析出94种VOCs,包括醛类、酯类、酮类及含硫化合物等挥发性成分。HS-SPME-GC-MS和HS-GC-IMS检出的挥发性物质种类和含量存在差异,共有VOCs有15种,二者结果互为补充,结合使用可以较全面系统地表征芜菁冻干片的挥发性成分。PCA和PLS-DA结果表明,2种方法均能够有效区分3种芜菁冻干片。通过变量投影重要度分别筛选了59种和23种差异VOCs,该结果可为芜菁冻干片VOCs的差异分析提供参考方法。 展开更多
关键词 芜菁冻干片 挥发性有机物 顶空-固相微萃取-气相色谱-质谱 顶空-气相色谱-离子迁移谱 变量投影重要度
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应力-渗流-溶蚀耦合作用下三维岩石裂隙渗透特性数值计算研究 被引量:2
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作者 申林方 吕倩文 +3 位作者 刘文连 张家明 杨鸿忠 李泽 《岩土工程学报》 北大核心 2025年第2期428-437,共10页
基于格子Boltzmann方法采用双分布函数分别模拟渗流速度场与溶质浓度场的演化过程,建立了三维岩石裂隙应力-渗流-溶蚀耦合作用机制的数值计算模型,并讨论了渗流流速、法向应力、溶蚀反应速率等因素对裂隙渗透特性演化规律的影响。结果表... 基于格子Boltzmann方法采用双分布函数分别模拟渗流速度场与溶质浓度场的演化过程,建立了三维岩石裂隙应力-渗流-溶蚀耦合作用机制的数值计算模型,并讨论了渗流流速、法向应力、溶蚀反应速率等因素对裂隙渗透特性演化规律的影响。结果表明:在渗流流速较低时,壁面溶蚀出来的离子得不到及时输运,使得出口处浓度较高溶蚀速度慢,裂隙结构呈“喇叭口”状。增大法向应力会减小裂隙开度,减慢溶质的运移速率,使得裂隙出口处的溶蚀速率显著降低,从而限制了其渗透率的发展。当壁面溶蚀反应速率较小时,裂隙渗透率呈持续缓慢增长的状态;随着溶蚀反应速率增加,出口处的溶蚀量会明显小于入口处,导致出口处壁面发生显著溶蚀之前,裂隙渗透率发展缓慢,此后渗透率便呈急速突变增长趋势。研究成果能够为酸蚀作用下岩石裂隙渗透能力的定量评价提供重要理论支撑。 展开更多
关键词 岩石裂隙 应力-渗流-溶蚀耦合 渗透特性 格子BOLTZMANN方法 数值计算
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黄芪-莪术-蚤休配伍调控PINK1/Parkin信号通路抑制小鼠结肠癌生长转移的研究 被引量:1
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作者 陈思 梁众擎 +5 位作者 苏婷婷 张慧兰 梁研 祁恒奕 陈怀祖 唐德才 《南京中医药大学学报》 北大核心 2025年第4期473-482,共10页
目的探讨黄芪-莪术-蚤休(芪-术-蚤)角药配伍基于PINK1/Parkin/EMT信号通路抑制结肠癌生长和转移的影响。方法30只BALB/c雄性小鼠,随机分为空白组、模型组、阳性对照组、芪-术-蚤高剂量组(5.85 g·kg^(-1))、芪-术-蚤低剂量组(2.925 ... 目的探讨黄芪-莪术-蚤休(芪-术-蚤)角药配伍基于PINK1/Parkin/EMT信号通路抑制结肠癌生长和转移的影响。方法30只BALB/c雄性小鼠,随机分为空白组、模型组、阳性对照组、芪-术-蚤高剂量组(5.85 g·kg^(-1))、芪-术-蚤低剂量组(2.925 g·kg^(-1)),每组6只,使用结肠癌CT26.WT细胞构建小鼠原位结肠癌模型。给药15 d后,取各组小鼠肿瘤、肝脏组织,HE病理染色评估肿瘤转移情况,透射电镜观察肿瘤组织线粒体自噬现象,Western blot、免疫组化(IHC)检测线粒体自噬相关蛋白PINK1、Parkin、p62、LC3-Ⅱ/LC3-Ⅰ表达情况,Western blot、qPCR、IHC检测EMT相关E-cadherin、N-cadherin、Vimentin、Snail蛋白和mRNA表达情况。结果与模型组相比,给药组小鼠肿瘤体积明显变小、转移灶数目变少,肝脏组织发生改变,小鼠生长状态得到明显改善;芪-术-蚤给药组肿瘤组织线粒体发生了选择性自噬现象,伴随着自噬小体的产生;芪-术-蚤给药组影响了PINK1/Parkin通路介导的线粒体自噬生物学过程:PINK1、Parkin、p62、LC3-Ⅱ/LC3-Ⅰ均有一定程度上调(P<0.05,P<0.01),且高剂量组效果优于低剂量组(P<0.05,P<0.01);芪-术-蚤给药组降低了EMT相关N-cadherin、Vimentin、Snail的蛋白含量与mRNA水平(P<0.05,P<0.01),同时增高了E-cadherin的蛋白与mRNA水平(P<0.05,P<0.01),且高剂量组均优于低剂量组(P<0.05,P<0.01)。结论芪-术-蚤角药配伍一定程度抑制结肠癌原位移植瘤小鼠模型肿瘤生长和转移,其机制可能是通过PINK1/Parkin信号通路扭转线粒体功能异常,抑制上皮-间质转化(EMT)过程,达到治疗结肠癌的作用。 展开更多
关键词 -- 线粒体自噬 PINK1/Parkin信号通路 上皮-间质转化 结肠癌
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多类混凝土损伤比强度理论及塑性-损伤模型研究进展与应用 被引量:1
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作者 丁发兴 吴霞 +7 位作者 吕飞 王文君 孙浩 SADAT Said Ikram 许云龙 王恩 王莉萍 余志武 《铁道科学与工程学报》 北大核心 2025年第2期690-711,共22页
为完善混凝土强度理论和塑性-损伤模型,通过参考岩石损伤比强度理论,根据现有普通混凝土、再生混凝土、轻骨料混凝土和纤维混凝土等多类混凝土多轴强度试验数据,推荐损伤比变量中的五经验系数取值,完善多类混凝土损伤比强度理论并揭示... 为完善混凝土强度理论和塑性-损伤模型,通过参考岩石损伤比强度理论,根据现有普通混凝土、再生混凝土、轻骨料混凝土和纤维混凝土等多类混凝土多轴强度试验数据,推荐损伤比变量中的五经验系数取值,完善多类混凝土损伤比强度理论并揭示约束混凝土工作原理。分析表明,随着静水压力的增加,混凝土压损伤比将由单轴受压时为1左右线性递减至小于0.5,八面体剪应力先增大后减小,轴向峰值应力提升为某一定值,压损伤比取值减小引发非弹性体积膨胀减小至不变,因而导致混凝土由单轴受压脆性破坏向多轴受压塑性破坏转变,该理论为钢管混凝土柱中发挥混凝土耗能潜力提供理论依据。依据混凝土损伤比强度理论,确定多类混凝土塑性-损伤模型中的三轴强度参数,包括膨胀角、拉压子午线强度比值和二轴等压与单轴抗压强度比值,并建议常温静力荷载下多类混凝土的单轴受压、受拉应力-应变曲线方程及其参数表达式,常温地震荷载下普通混凝土的单轴受压、受拉应力-应变曲线方程及其参数表达式,以及火灾升温环境下普通混凝土的单轴受压、受拉应力-应变曲线方程及其参数表达式,建立约束混凝土三轴塑性-损伤模型。介绍多类混凝土塑性-损伤模型在钢-混凝土组合结构有限元模型中的应用,模型中混凝土采用实体单元而钢管与钢梁采用壳单元,可模拟钢管与混凝土之间的界面滑移与约束作用,当采取增强约束拉筋强柱构造方法时可提升钢管混凝土柱及其结构的承载力、抗震与抗火性能。 展开更多
关键词 混凝土 损伤比 强度理论 塑性-损伤模型 三轴参数 应力-应变曲线 实体-壳单元模型
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双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质 被引量:1
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作者 张宇红 李博 +4 位作者 陈自然 李渊 徐友辉 张莉萍 何旭东 《原子与分子物理学报》 CAS 北大核心 2025年第2期15-23,共9页
使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与... 使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料. 展开更多
关键词 双偶氮 二苯并[b i]噻蒽-[2 3-b]苯-5 7 12 14-四酮 密度泛函理论 电子吸收光谱 二阶非线性光学性质
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长三角地区“产-才-城”适配的时空演化及影响因素研究 被引量:2
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作者 黄永春 周炯岚 +1 位作者 李娜 宫尚俊 《华东经济管理》 北大核心 2025年第4期9-20,共12页
在长三角一体化发展中,产业、人才和城市的融合协调是推进区域高质量发展的重要途径。文章根据2011—2022年长三角地区41个城市数据,探索“产-才-城”适配度的时空格局演化趋势及其影响因素。结果表明:在时间趋势上,长三角地区“产-才-... 在长三角一体化发展中,产业、人才和城市的融合协调是推进区域高质量发展的重要途径。文章根据2011—2022年长三角地区41个城市数据,探索“产-才-城”适配度的时空格局演化趋势及其影响因素。结果表明:在时间趋势上,长三角地区“产-才-城”适配度呈稳定增长态势,多极化现象渐显;在空间分异中,呈“西低东高”的地域差异,形成以长三角核心城市为主的高水平聚集带。同时,“产-才-城”适配度的空间自相关显著为正,具有空间俱乐部收敛特征。影响因素分析显示,社会保障能力和金融发展水平是提升“产-才-城”适配度的关键因素,对外贸易水平、科技支出水平和政府调控能力的作用稍弱,且存在地域差异。 展开更多
关键词 长三角一体化 “产--城”适配 时空演化 耦合协调
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基于电压-功率灵敏度的有源配电网数据驱动电压协调控制策略 被引量:1
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作者 张波 文晓君 吴璇 《电力系统及其自动化学报》 北大核心 2025年第1期35-42,共8页
随着分布式光伏渗透率的不断提高,实现配电网电压的快速精确调控变得愈加重要。首先,建立多输入-多输出的电压-功率灵敏度BP神经网络回归预测模型,得到功率参数、节点电压与电压-功率灵敏度间的非线性映射关系;其次,构建高比例光伏有源... 随着分布式光伏渗透率的不断提高,实现配电网电压的快速精确调控变得愈加重要。首先,建立多输入-多输出的电压-功率灵敏度BP神经网络回归预测模型,得到功率参数、节点电压与电压-功率灵敏度间的非线性映射关系;其次,构建高比例光伏有源配电网电压协调控制策略,基于电压-功率灵敏度降序调控原则,通过无功补偿和有功削减结合的两阶段电压调控模式实现配电网节点电压的快速调控;最后,利用IEEE 33和IEEE 141节点典型配电系统的仿真,计算分析验证所提方法的正确性和有效性。 展开更多
关键词 BP神经网络 数据驱动 电压-功率灵敏度 电压协调控制 有源配电网
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