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Two-phase guidance law for impact time control under physical constraints 被引量:8
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作者 Yang TANG Xiaoping ZHU +1 位作者 Zhou ZHOU Fei YAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第11期2946-2958,共13页
An impact-time-control guidance law is required for the simultaneous attack of suicide attack unmanned aerial vehicles.Based on the nonlinear model,a two-phase guidance strategy is proposed.The impact time is derived ... An impact-time-control guidance law is required for the simultaneous attack of suicide attack unmanned aerial vehicles.Based on the nonlinear model,a two-phase guidance strategy is proposed.The impact time is derived in a simple analytical form of initial states and switching states,and it can be controlled by switching at an appropriate range.Firstly,a two-phase guidance law is designed to make the magnitude of the heading error decrease monotonically from its initial value to zero.And then,the feasible interval of the switching ranges and of the impact times under the acceleration constraint are given analytically in sequence.Furthermore,a general form of twophase guidance law is proposed,which allows the magnitude of the heading error to increase in the first phase,to improve the applicability of the methodology.Having the same structure as proportional navigation guidance with a time-varying gain,the proposed algorithms are simple and easy to implement.The corresponding feedback form is presented for realistic implementation.When a predefined impact time is taken within its permissible set,the constraints on the acceleration and fieldof-view will not be violated during the interception.Finally,simulations validate the effectiveness of the methodology in impact time control and salvo attack. 展开更多
关键词 Acceleration constraint Field-of-view constraint GUIDANCE impact time control Switching
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A hybrid proportional navigation based two-stage impact time control guidance law 被引量:3
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作者 HUANG Jia CHANG Sijiang CHEN Shengfu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第2期461-473,共13页
To improve applicability and adaptability of the impact time control guidance(ITCG) in practical engineering, a twostage ITCG law with simple but effective structure is proposed based on the hybrid proportional naviga... To improve applicability and adaptability of the impact time control guidance(ITCG) in practical engineering, a twostage ITCG law with simple but effective structure is proposed based on the hybrid proportional navigation, namely, the pureproportional-navigation and the retro-proportional-navigation.For the case with the impact time error less than zero, the first stage of the guided trajectory is driven by the retro-proportionalnavigation and the second one is driven by the pure-proportionalnavigation. When the impact time error is greater than zero, both of the stages are generated by the pure-proportional-navigation but using different navigation gains. It is demonstrated by twoand three-dimensional numerical simulations that the proposed guidance law at least has comparable results to existing proportional-navigation-based ITCG laws and is shown to be advantageous in certain circumstances in that the proposed guidance law alleviates its dependence on the time-to-go estimation, consumes less control energy, and adapts itself to more boundary conditions and constraints. The results of this research are expected to be supplementary to the current research literature. 展开更多
关键词 missile guidance law impact time control pure-proportional-navigation retro-proportional-navigation time-to-go estimation
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Impact time control guidance against maneuvering targets based on a nonlinear virtual relative model 被引量:3
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作者 Yuru BIN Hui WANG +2 位作者 Defu LIN Yaning WANG Xin SUN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第7期444-459,共16页
Aiming at the problem of high-precision interception of air-maneuvering targets with impact time constraints,this paper proposes a novel guidance law based on a nonlinear virtual relative model in which the origin is ... Aiming at the problem of high-precision interception of air-maneuvering targets with impact time constraints,this paper proposes a novel guidance law based on a nonlinear virtual relative model in which the origin is attached to the target.In this way,the original maneuvering target is transformed into a stationary one.A polynomial function of the guidance command in the range domain with two unknown coefficients is introduced into the virtual model,one of the coefficients is determined to achieve the impact time constraint,and the other is determined to satisfy a newly defined virtual look angle constraint.For meeting the terminal constraints simultaneously,the guidance command can finally be obtained.The resulting solution is represented as a combination of proportional navigation guidance-like term which is aimed to meet the zero miss distance constraint,a bias term for impact time control by adjusting the length of the homing trajectory,and an additional term for target maneuvers.Numerous simulations demonstrate that the proposed law achieves an acceptable impact time error for various initial conditions against different types of maneuvering targets and shows more effective performance in comparison with those of other existing guidance laws. 展开更多
关键词 impact time control Maneuvering targets Polynomial guidance Virtual relative model Virtual look angle constraint
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Sliding mode control and Lyapunov based guidance law with impact time constraints 被引量:6
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作者 Xiaojian Zhang Mingyong Liu Yang Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1186-1192,共7页
This paper analyses the issue of impact time control of super-cavitation weapons impact fixed targets which mainly refer to the ships or submarines who lost power, but still have combat capability. Control over impact... This paper analyses the issue of impact time control of super-cavitation weapons impact fixed targets which mainly refer to the ships or submarines who lost power, but still have combat capability. Control over impact time constraints of guidance law(ITCG) is derived by using sliding mode control(SMC) and Lyapunov stability theorem. The expected impact time is realized by using the notion of attack process and estimated time-to-go to design sliding mode surface(SMS). ITCG contains equivalent and discontinuous guidance laws, once state variables arrive at SMS,the equivalent guidance law keeps the state variables on SMS,then the discontinuous guidance law enforces state variables to move and reach SMS. The singularity problem of ITCG is also analyzed. Theoretical analysis and numerical simulation results are given to test the effectiveness of ITCG designed in this paper. 展开更多
关键词 Lyapunov stability sliding mode control impact time salvo attack time-TO-GO guidance law
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Impact angle control over composite guidance law based on feedback linearization and finite time control 被引量:8
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作者 ZHANG Xiaojian LIU Mingyong +1 位作者 LI Yang ZHANG Feihu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期1036-1045,共10页
The impact angle control over guidance(IACG) law against stationary targets is proposed by using feedback linearization control(FLC) and finite time control(FTC). First, this paper transforms the kinematics equation o... The impact angle control over guidance(IACG) law against stationary targets is proposed by using feedback linearization control(FLC) and finite time control(FTC). First, this paper transforms the kinematics equation of guidance systems into the feedbackable linearization model, in which the guidance law is obtained without considering the impact angle via FLC. For the purpose of the line of sight(LOS) angle and its rate converging to the desired values, the second-order LOS angle is considered as a double-integral system. Then, this paper utilizes FTC to design a controller which can guarantee the states of the double-integral system converging to the desired values. Numerical simulation illustrates the performance of the IACG, in contrast to the existing guidance law. 展开更多
关键词 guidance law impact angle feedback linearization finite time control global stabilization
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Optimal three-dimensional impact time guidance with seeker’s field-of-view constraint 被引量:15
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作者 Shaoming HE Chang-Hun LEE +1 位作者 Hyo-Sang SHIN Antonios TSOURDOS 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第2期240-251,共12页
This paper proposes a new three-dimensional optimal guidance law for impact time control with seeker’s Field-of-View(FOV) constraint to intercept a stationary target. The proposed guidance law is devised in conjuncti... This paper proposes a new three-dimensional optimal guidance law for impact time control with seeker’s Field-of-View(FOV) constraint to intercept a stationary target. The proposed guidance law is devised in conjunction with the concept of biased Proportional Navigation Guidance(PNG). The guidance law developed leverages a nonlinear function to ensure the boundedness of velocity lead angle to cater to the seeker’s FOV limit. It is proven that the impact time error is nullified in a finite-time under the proposed method. Additionally, the optimality of the biased command is theoretically analyzed. Numerical simulations confirm the superiority of the proposed method and validate the analytic findings. 展开更多
关键词 Applied optimal control Field-of-view constraint impact time control Missile guidance Optimal error dynamics
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Guidance law with impact time and impact angle constraints 被引量:59
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作者 Zhang Youan Ma Guoxin Liu Aili 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第4期960-966,共7页
A novel closed-form guidance law with impact time and impact angle constraints is pro- posed for salvo attack of anti-ship missiles, which employs missile's normal acceleration (not jerk) as the control command dir... A novel closed-form guidance law with impact time and impact angle constraints is pro- posed for salvo attack of anti-ship missiles, which employs missile's normal acceleration (not jerk) as the control command directly. Firstly, the impact time control problem is formulated as tracking the designated time-to-go (the difference between the designated impact time and the current flight time) for the actual time-to-go of missile, and the impact angle control problem is formulated as tracking the designated heading angle for the actual heading angle of missile. Secondly, a biased proportional navigation guidance (BPNG) law with designated heading angle constraint is constructed, and the actual time-to-go estimation for this BPNG is derived analytically by solving the system differential equations. Thirdly, by adding a feedback control to this constructed BPNG to eliminate the time-to-go errorthe difference between the standard time-to-go and the actual time-to-go, a guidance law with adjustable coefficients to control the impact time and impact angle simultaneously is developed. Finally, simulation results demonstrate the performance and feasibility of the proposed approach. 展开更多
关键词 Feedback control Guidance law impact angle impact time Missiles Proportional navigation guidance
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Real Time Chatter Vibration Control System in High Speed Milling
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作者 Hyeok Kim Mun-Ho Cho +2 位作者 Jun-Yeong Koo Jong-Whan Lee Jeong-Suk Kim 《材料科学与工程(中英文A版)》 2015年第5期221-229,共9页
关键词 振动控制系统 高速铣削加工 实时控制 快速傅里叶变换 切削颤振 刀具寿命 切削条件 表面完整性
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An adaptive fast fixed-time guidance law with an impact angle constraint for intercepting maneuvering targets 被引量:21
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作者 Yao ZHANG Shengjing TANG Jie GUO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第6期1327-1344,共18页
Sliding mode guidance laws based on a conventional terminal sliding mode guarantees only finite-time convergence, which verifies that the settling time is required to be estimated by selecting appropriate initial laun... Sliding mode guidance laws based on a conventional terminal sliding mode guarantees only finite-time convergence, which verifies that the settling time is required to be estimated by selecting appropriate initial launched conditions. However, rapid convergence to a desired impact angle within a uniform bounded finite time is important in most practical guidance applications. A uniformly finite-time/fixed-time convergent guidance law means that the convergence(settling) time is predefined independently on initial conditions, that is, a closed-loop convergence time can be estimated a priori by guidance parameters. In this paper, a novel adaptive fast fixed-time sliding mode guidance law to intercept maneuver targets at a desired impact angle from any initial heading angle,with no problems of singularity and chattering, is designed. The proposed guidance law achieves system stabilization within bounded settling time independent on initial conditions and achieves more rapid convergence than those of fixed-time stable control methods by accelerating the convergence rate when the system is close to the origin. The achieved acceleration-magnitude constraints are rigorously enforced, and the chattering-free property is guaranteed by adaptive switching gains.Extensive numerical simulations are presented to validate the efficiency and superiority of the proposed guidance law for different initial engagement geometries and impact angles. 展开更多
关键词 Adaptive gain tuning Fixed-time convergence impact angle constraint Missile guidance Nonsingular terminal sliding mode control
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Three-dimensional adaptive finite-time guidance law for intercepting maneuvering targets 被引量:21
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作者 Yujie SI Shenmin SONG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第6期1985-2003,共19页
To intercept maneuvering targets at desired impact angles, a three-dimensional terminal guidance problem is investigated in this study. Because of a short terminal guidance time, a finitetime impact angle control guid... To intercept maneuvering targets at desired impact angles, a three-dimensional terminal guidance problem is investigated in this study. Because of a short terminal guidance time, a finitetime impact angle control guidance law is developed using the fast nonsingular terminal sliding mode control theory. However, the guidance law requires the upper bound of lumped uncertainty including target acceleration, which may not be accurately obtained. Therefore, by adopting a novel reaching law, an adaptive sliding mode guidance law is provided to release the drawback. At the same time, this method can accelerate the convergence rate and weaken the chattering phenomenon to a certain extent. In addition, another novel adaptive guidance law is also derived; this ensures systems asymptotic and finite-time stability without the knowledge of perturbations bounds.Numerical simulations have demonstrated that all the three guidance laws have effective performances and outperform the traditional terminal guidance laws. 展开更多
关键词 Adaptive control Finite-time guidance law impact angle Sliding mode control Three-dimensional guidance law
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Technical development and future prospects of cooperative terminal guidance based on knowledge graph analysis:a review 被引量:1
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作者 Shuangxi LIU Zehuai LIN +1 位作者 Wei HUANG Binbin YAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第7期605-634,共30页
Cooperative guidance is a method for achieving combat objectives through information sharing and cooperative effects,and has emerged as a significant research area in the fields of missile guidance and systematic warf... Cooperative guidance is a method for achieving combat objectives through information sharing and cooperative effects,and has emerged as a significant research area in the fields of missile guidance and systematic warfare.This study presents a systematic review and analysis of current research on cooperative guidance.First,a bibliometric analysis is conducted on 513 articles using the Scopus database and CiteSpace software to assess keyword clustering,keyword cooccurrence,and keyword burst,and to later visualize the results.Second,fundamental theories of cooperative guidance,including relative motion modeling methods,algebraic graph theory,and multi-agent consensus theory,are summarized.Subsequently,an overview of current cooperative laws and corresponding analysis methods is provided,with categorization based on the cooperative structure and convergence performance.Finally,we summarize current research developments based on five perspectives and propose a developmental framework based on five layers(cyber,physical,decision,information,and system),discussing potential future advancements in cooperative terminal guidance.This framework emphasizes five key areas of research:networked,heterogeneous,integrated,intelligent,and group cooperations,with the goal of offering trends and insights for futurework. 展开更多
关键词 Cooperative guidance Guidance law Multiple missiles Cooperative operations Guidance and control impact time control impact angle control Consensus theory CiteSpace analysis
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半主动碰撞耗能装置减震性能分析及优化设计研究
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作者 鲁正 张家伟 《地震工程与工程振动》 北大核心 2025年第1期74-84,共11页
文中提出了一种具有碰撞出力时机可控的半主动碰撞耗能装置(semi-active impact damper,SAID),旨在控制地震激励下土木工程结构的多模态振动,SAID无需额外的控制元件,依靠其碰撞作动力干预结构振幅的积累实现振动控制。根据SAID力学模... 文中提出了一种具有碰撞出力时机可控的半主动碰撞耗能装置(semi-active impact damper,SAID),旨在控制地震激励下土木工程结构的多模态振动,SAID无需额外的控制元件,依靠其碰撞作动力干预结构振幅的积累实现振动控制。根据SAID力学模型和对应半主动控制策略提出了一种碰撞净距可调的装置构造,并开展了振动台试验,探究了SAID系统在5层框架结构的减震效果。研究表明,SAID系统可以有效减小结构顶层加速度和结构层间位移,依据时频能量分析可以发现SAID能够在可控碰撞中将结构的振动能量由低阶模态向高阶模态转移,从而快速耗散能量,并有效限制主导模态所引起的结构反应。本研究进一步提出了SAID系统的优化方案增强型半主动碰撞耗能装置(enhanced semi-active impact damper,ESAID)系统,以减少冲击引起的加速度突变的负面影响,同时提高SAID系统的减震性能。 展开更多
关键词 半主动碰撞耗能装置 多模态振动控制 时频能量分析 碰撞耗能装置 半主动控制
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Distributed three-dimensional cooperative guidance via receding horizon control 被引量:11
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作者 Zhao Jiang Zhou Rui 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第4期972-983,共12页
The paper presents a new three-dimensional (3D) cooperative guidance approach by the receding horizon control (RHC) technique. The objective is to coordinate the impact time of a group of interceptor missiles against ... The paper presents a new three-dimensional (3D) cooperative guidance approach by the receding horizon control (RHC) technique. The objective is to coordinate the impact time of a group of interceptor missiles against the stationary target. The framework of a distributed RHC scheme is developed, in which each interceptor missile is assigned its own finite-horizon optimal control problem (FHOCP) and only shares the information with its neighbors. The solution of the local FHOCP is obtained by the constrained particle swarm optimization (PSO) method that is integrated into the distributed RHC framework with enhanced equality and inequality constraints. The numerical simulations show that the proposed guidance approach is feasible to implement the cooperative engagement with satisfied accuracy of target capture. Finally, the computation efficiency of the distributed RHC scheme is discussed in consideration of the PSO parameters, control update period and prediction horizon. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license. 展开更多
关键词 Distributed algorithms impact time Missile guidance Multiple missiles Particle swarm optimization (PSO) Receding horizon control (RHC) Three-dimensional (3D)
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计及尾流效应时滞影响的风电场频率响应建模及自适应综合惯性控制
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作者 周涛 杜可可 《控制与信息技术》 2025年第5期31-39,共9页
随着风电在电力系统中渗透率的不断提高,其波动性与间歇性对电网频率的稳定性带来了严峻挑战。为了减少风电场内部尾流效应和时滞效应对风电场整体调频能力的影响,本文研究了计及尾流效应时滞影响的风电场频率响应建模方法与风电机组自... 随着风电在电力系统中渗透率的不断提高,其波动性与间歇性对电网频率的稳定性带来了严峻挑战。为了减少风电场内部尾流效应和时滞效应对风电场整体调频能力的影响,本文研究了计及尾流效应时滞影响的风电场频率响应建模方法与风电机组自适应综合惯性控制策略。首先详细分析了风电场尾流效应的时滞影响,建立了计及尾流效应的风电场频率响应模型,以准确描述其在电力系统中的动态特性;在此基础上,提出了基于风速和风电机组转速的模糊自适应综合惯性控制策略,通过动态调整控制系数,计及尾流效应时滞影响并充分利用风电机组的转子动能完成系统调频。仿真结果表明,所提策略在不同负荷扰动和风速条件下均能有效提升频率最低点,减少频率波动,展现出良好的适应性和稳定性,显著提高了风电场的调频性能和电力系统的频率稳定性。 展开更多
关键词 风电场 尾流效应 时滞影响 模糊控制 综合惯性控制
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考虑攻击时间与区域封控的协同制导方法
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作者 郭征 李国飞 +1 位作者 熊华 吴云洁 《系统仿真学报》 北大核心 2025年第11期2714-2723,共10页
针对机动目标的多飞行器协同打击问题,提出了攻击时间控制与末端区域封控下的协同制导方法。利用分布式干扰观测器达到对目标机动的估计,基于构建的攻击时间一致性协同误差设计视线方向协同制导律,实现对目标的指定时间同时命中;依据目... 针对机动目标的多飞行器协同打击问题,提出了攻击时间控制与末端区域封控下的协同制导方法。利用分布式干扰观测器达到对目标机动的估计,基于构建的攻击时间一致性协同误差设计视线方向协同制导律,实现对目标的指定时间同时命中;依据目标运动状态设计末端区域封控指令,构造滑模面并设计视线法向制导律,保证滑模面及视线角的收敛。理论分析表明:所设计制导方法可实现攻击时间控制下对目标的区域封控,数值仿真验证了方法的有效性。 展开更多
关键词 多飞行器 协同制导 攻击时间控制 区域封控 机动目标
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考虑视场角约束的视角塑形攻击时间制导律
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作者 郭子淳 王乐 +2 位作者 席建祥 秦明星 高久安 《电光与控制》 北大核心 2025年第8期7-11,24,共6页
考虑精确制导任务中存在的导引头视场角约束问题,提出一种基于视角塑形的攻击时间制导律。首先,构建关于无量纲弹目距离的三次多项式形式参考视角剖面,将攻击时间和最大视角表示为剖面参数的方程,通过求解该参数方程获得满足约束的参考... 考虑精确制导任务中存在的导引头视场角约束问题,提出一种基于视角塑形的攻击时间制导律。首先,构建关于无量纲弹目距离的三次多项式形式参考视角剖面,将攻击时间和最大视角表示为剖面参数的方程,通过求解该参数方程获得满足约束的参考视角剖面。其次,根据导弹的动力学模型设计跟踪参考视角剖面的制导指令,得到视场角约束下的攻击时间制导律,并推导对应的攻击时间可达域。所提出的制导律不依赖于剩余飞行时间估计、线性化模型和切换逻辑,且可以实现终端零控。最后,通过数值仿真验证所提制导律的有效性。 展开更多
关键词 攻击时间控制 视场角约束 视角塑形 制导律
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考虑路径点约束的攻击时间与攻击角度控制制导方法
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作者 雷刚 王和 +1 位作者 李少朋 罗炜 《中国惯性技术学报》 北大核心 2025年第2期172-178,共7页
为提升导弹武器在进行协同打击时的效能,对仅满足攻击时间与攻击角度控制的制导方法进行扩展,设计了一种带有路径点约束的多项式飞行轨迹,推导建立了指令加速度与飞行时间的关系。通过在飞行轨迹上设置路径点约束,改变了战术导弹的飞行... 为提升导弹武器在进行协同打击时的效能,对仅满足攻击时间与攻击角度控制的制导方法进行扩展,设计了一种带有路径点约束的多项式飞行轨迹,推导建立了指令加速度与飞行时间的关系。通过在飞行轨迹上设置路径点约束,改变了战术导弹的飞行轨迹,提高了导弹的机动突防能力。通过仿真对设计的制导方法进行验证,实验条件下所提方法的导弹攻击时间与攻击角度误差为0,脱靶量小于0.18 m,路径点偏差小于0.12 m。仿真结果表明所提出的制导方法能够有效实现攻击时间和攻击角度的控制且满足路径点约束。 展开更多
关键词 路径点约束 攻击时间与攻击角度控制 多项式
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新型冠状病毒感染疫情防控措施对克拉玛依市常见呼吸道传染病发病影响的定量评估 被引量:2
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作者 蔺洁 梁智超 +1 位作者 胥婉婷 曹明芹 《实用预防医学》 2025年第1期9-14,共6页
目的了解新型冠状病毒感染疫情防控措施对克拉玛依市常见呼吸道传染病发病影响作用,为政府部门采取有针对性干预措施提供依据。方法采用时间序列分析方法,按新型冠状病毒感染疫情前、新型冠状病毒感染疫情期间、新型冠状病毒感染疫情后... 目的了解新型冠状病毒感染疫情防控措施对克拉玛依市常见呼吸道传染病发病影响作用,为政府部门采取有针对性干预措施提供依据。方法采用时间序列分析方法,按新型冠状病毒感染疫情前、新型冠状病毒感染疫情期间、新型冠状病毒感染疫情后分阶段分析2016—2023年克拉玛依市肺结核、猩红热、流行性感冒、流行性腮腺炎4种常见呼吸道传染病发病数据,定量分析采取新型冠状病毒感染疫情防控措施和取消疫情防控措施对克拉玛依市常见呼吸道传染病发病的影响作用。结果用2016—2019年报告的肺结核、猩红热、流行性感冒和流行性腮腺炎发病数据,分别建立Holt-Winter加法模型、AR(9,0)模型、ARIMA(0,0,3)×(1,1,0)_(12)模型和简单季节模型,用最优模型拟合克拉玛依市2019年7—12月4种传染病报告发病数,预测相对误差在-0.020~0.028之间波动,用最优模型预测2020—2022年4种常见呼吸道传染病发病情况,肺结核2020—2022年实际发病数较预测值分别下降33.15%、24.57%、33.53%,猩红热较预测值分别下降92.65%、97.42%、91.69%,流行性感冒较预测值分别下降87.41%、96.67%、32.18%,流行性腮腺炎较预测值分别下降59.85%、51.47%、58.99%。用2020—2022年4种传染病报告发病数据建立简单季节模型,用最优模型拟合克拉玛依市2022年7—12月4种传染病报告发病数,预测相对误差在-0.292~0.081之间波动,用最优模型预测2020—2022年4种常见呼吸道传染病发病情况,肺结核2023年实际发病数较预测值上升59.38%,猩红热较预测值上升926.67%,流行性感冒较预测值上升666.67%,流行性腮腺炎较预测值下降3.33%。结论新型冠状病毒感染疫情防控措施对克拉玛依市呼吸道传染病有不同程度的降低发病水平作用,但降低发病水平的持久性有限。建议今后根据疫情防控措施对呼吸道传染病的影响效果,在各类呼吸道传染病高发期,有针对性、有重点的投入防控力量,事半功倍地提高疫情防控效果。 展开更多
关键词 疫情防控措施 时间序列 呼吸道传染病 发病影响
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调距桨轴系及轴内油管抗冲击性能研究
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作者 何书浩 孙威 +6 位作者 雷俊松 武于哲 施睿贇 王国亮 祁亮 马召召 周瑞平 《舰船科学技术》 北大核心 2025年第24期120-125,共6页
针对调距桨轴系及轴内油管抗冲击分析中传统动态设计法(Dynamic Design Analysis Method,DDAM)精度不足、全时域法效率低的问题,提出一种DDAM-时域法耦合的计算方法。将轴内油管简化为轴系的附加质量,通过DDAM法计算基准冲击谱;构建时... 针对调距桨轴系及轴内油管抗冲击分析中传统动态设计法(Dynamic Design Analysis Method,DDAM)精度不足、全时域法效率低的问题,提出一种DDAM-时域法耦合的计算方法。将轴内油管简化为轴系的附加质量,通过DDAM法计算基准冲击谱;构建时域冲击输入载荷,完成轴内油管精细化计算分析。以某型舰船调距桨轴系及轴内油管为对象,采用此方法对其进行抗冲击性能研究。结果表明,耦合方法计算耗时10 h,较全时域法计算时间降低67%,轴系最大综合应力响应为391.91 MPa,轴内油管最大应力响应为216.42 MPa,均低于材料许用应力值,满足抗冲击要求。为船舶推进系统抗冲击设计提供了一种“整体-分布”分层分析的高效研究方法。 展开更多
关键词 调距桨轴系 抗冲击性能 DDAM 时域分析
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机械式自动变速器离合器起步控制优化策略
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作者 陈东东 尹继辉 +2 位作者 韦茂松 王浩齐 张鹏雷 《交通科技与经济》 2025年第3期68-75,共8页
为解决电控机械式自动变速器(AMT)汽车起步阶段中离合器的接合控制问题,以AMT离合器为研究对象,以离合器结合速度为控制目标,选取冲击度和滑磨功作为评价指标,研究设计三输入单输出的自适应模糊神经控制策略,并与传统控制策略进行仿真... 为解决电控机械式自动变速器(AMT)汽车起步阶段中离合器的接合控制问题,以AMT离合器为研究对象,以离合器结合速度为控制目标,选取冲击度和滑磨功作为评价指标,研究设计三输入单输出的自适应模糊神经控制策略,并与传统控制策略进行仿真对比。研究结果表明,在低速、中速、高速3种起步意图下,控制策略优化后汽车所需的起步时间分别为2.03 s、1.80 s、1.75 s,少于模糊控制的2.18 s、2 s、1.80 s;产生的最大冲击度为8.02 m·s^(-3)、9 m·s^(-3)、9.80 m·s^(-3),低于模糊控制的8.25 m·s^(-3)、9.50 m·s^(-3)、9.90 m·s^(-3)和PID控制下的8.17 m·s^(-3)、9.27 m·s^(-3)、9.85 m·s^(-3);产生的滑磨功为6.20 kJ、5.45 kJ、5.20 kJ,少于模糊控制下产生的6.60 kJ、5.65 kJ、5.49 kJ和PID控制下的6.46 kJ、5.61 kJ、5.46 kJ。合理的冲击度下起步平顺性较好,滑磨功的减少使得离合器使用寿命更长,自适应模糊神经控制较之传统模糊控制效果更好,具有更高的自适应能力和鲁棒性。 展开更多
关键词 汽车工程 离合器起步控制 自适应模糊控制策略 起步时间 冲击度 滑磨功
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