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Dynamics of a Nonautonomous Plant Disease Model with General Nonlinear Incidence Rate and Time-Varying Impulse 被引量:1
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作者 Jianping Wang Xue Zhang +1 位作者 Juanjuan Wang Quanben Sun 《Journal of Applied Mathematics and Physics》 2019年第10期2518-2530,共13页
In this paper, for controlling the spread of plant diseases, a nonautonomous SEIS (Susceptible → Exposed → Infectious → Susceptible) epidemic model with a general nonlinear incidence rate and time-varying impulsive... In this paper, for controlling the spread of plant diseases, a nonautonomous SEIS (Susceptible → Exposed → Infectious → Susceptible) epidemic model with a general nonlinear incidence rate and time-varying impulsive control strategy is proposed and investigated. This novel model could result in an objective criterion on how to control plant disease transmission by replanting of healthy plants and removal of infected plants. Using the method of small amplitude perturbation, the sufficient conditions under which guarantee the globally attractive of the disease-free periodic solution and the permanence of the disease are obtained, that is, the disease dies out if R12>1. 展开更多
关键词 PLANT Disease NONAUTONOMOUS Model TIME-VARYING impulse general Nonlinear INCIDENCE PERMANENCE
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基于System Generator的宽带电力线脉冲噪声实现方法 被引量:10
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作者 王毅 田富公 +3 位作者 侯兴哲 郑可 叶君 李松浓 《电力系统自动化》 EI CSCD 北大核心 2017年第12期218-223,共6页
随机脉冲噪声是影响用电信息采集系统中宽带电力线载波(BPLC)通信的关键因素。目前的评估测试技术中缺乏标准化的宽带电力线噪声建模和实现方法。研究了经典的Middleton Class-A脉冲噪声模型,分析了二项分布逼近泊松分布的条件,从伯努... 随机脉冲噪声是影响用电信息采集系统中宽带电力线载波(BPLC)通信的关键因素。目前的评估测试技术中缺乏标准化的宽带电力线噪声建模和实现方法。研究了经典的Middleton Class-A脉冲噪声模型,分析了二项分布逼近泊松分布的条件,从伯努利实验模型出发,依据Middleton Class-A模型的脉冲指数设定满周期线性同余法生成伪随机序列的阈值,通过判定阈值以获取特定强度的泊松序列。该序列在加权因子部分进行数值运算,得到特定状态的噪声方差,利用乘法器与高斯白噪声序列相乘。所提Class-A脉冲噪声的System Generator模块化设计方法能够实现快速的算法验证,通过对比现场可编程门阵列(FPGA)输出与理论随机脉冲噪声的统计特性,证明了该实现方法的有效性与准确性。 展开更多
关键词 电力线载波通信 现场可编程门阵列 System generator Middleton Class-A 脉冲噪声 线性同余
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Impulsive generalized synchronization of chaotic system 被引量:1
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作者 张荣 徐振源 何雪明 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1912-1917,共6页
In this paper, with a given manifold y = H(x), we have constructed a response system for a continuous-time chaotic system as a drive system, and used impulsive control theory to demonstrate theoretically that this r... In this paper, with a given manifold y = H(x), we have constructed a response system for a continuous-time chaotic system as a drive system, and used impulsive control theory to demonstrate theoretically that this response system can achieve impulsive generalized synchronization (GS) with the drive system. Our theoretical result is supported by numerical examples. 展开更多
关键词 synchronization manifold impulsive generalized synchronization impulsive control impulsive differential equation
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Influence of an irradiation of a liquid phase by nanosecond electromagnetic impulses (NEMI) on properties of metals and alloys
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作者 RI E H RI Hosen +1 位作者 DOROFEEV S V KUHARENKO E B 《Rare Metals》 SCIE EI CAS CSCD 2007年第S1期14-19,共6页
The results of research on influence of an irradiation of a liquid phase by nanosecond electromagnetic impulses(NEMI) on processes of crystallization and structurization,physicomechanical and operational properties of... The results of research on influence of an irradiation of a liquid phase by nanosecond electromagnetic impulses(NEMI) on processes of crystallization and structurization,physicomechanical and operational properties of copper,aluminium and alloys on their basis(bronze and silumin) were presented. 展开更多
关键词 generator NEMI nanosecond electromagnetic impulses corrosion resistant heat resistance
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Proper Understanding of the Nerve Impulses and the Action Potential
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作者 Salama Abdelhady 《World Journal of Neuroscience》 2023年第3期103-117,共15页
Neurologists define the transmission of nerve impulses across the membranes of the neural cells as a result of difference in the concentration of ions while they measured an electric potential, called as an action pot... Neurologists define the transmission of nerve impulses across the membranes of the neural cells as a result of difference in the concentration of ions while they measured an electric potential, called as an action potential, which allows the propagation of such nerve impulses as electrical signals. Such measurements should guide them to a logical explanation of the nerve impulses as electric charges driven by the measured action potential. However, such logical conclusion, or explanation, is ignored due to a wrong definition of the flow of electric charges as a flow of electrons that cannot pass through neural networks. According to recent studies, electric charges are properly defined as electromagnetic (EM) waves whose energy is expressed as the product of its propagating electric potential times their entropy flow which is adhered to the flow of such energy. Such definition matches the logical conclusion of the nerve impulses as electric charges, as previously explained, and defines the entropy of the neural network, measured by Ammeters, in Watt or Joule/Volt. The measured entropy represents a neurodiagnostic property of the neural networks that measures its capacity to allow the flow of energy per unit action potential. Theoretical verification of the innovative definition of nerve impulses is presented by following an advanced entropy approach. A proper review of the machine records of the stimulating electric charges, used in the diagnosis of the neural networks, and the stimulated nerve impulses or stimulated responses, represents practical verifications of the innovative definitions of the electric charges and the nerve impulses. Comparing the functioning of the thermoelectric generators and the brain neurons, such neurons are defined as thermoelectric generators of the electric nerve impulses and their propagating, or action, potential. 展开更多
关键词 Nerve impulses Action Potential Electric Charges ENTROPY Electromagnetic Waves Thermoelectric generators
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Distributional Relations on Impulse Radiating Surface and Point Type Sources
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作者 Burak Polat 《Journal of Mathematics and System Science》 2012年第2期72-81,共10页
The electromagnetic field relations are demonstrated on impulse radiating surface and point type sources, which are characterized by first and second order singularities at rest in a Schwartz-Sobolev space setting. Th... The electromagnetic field relations are demonstrated on impulse radiating surface and point type sources, which are characterized by first and second order singularities at rest in a Schwartz-Sobolev space setting. The investigation starts with a general introduction to Schwartz-Sobolev distributions, the electromagnetic field equations and various modes of impulsive radiation. This is followed by an outline of temporal distributional relations in arbitrary media and distributional derivative operations on an arbitrary regular surface, all of which are employed in an investigation of impulse radiation mechanism on single and double layer sources. Similar steps are followed in a description of point distributions and investigation of impulse radiation mechanism on electric and magnetic point dipoles. 展开更多
关键词 generalized functions electromagnetic phenomena single and double layers point sources impulse radiation.
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New Criteria for Boundedness in Terms of Two Measures for Impulsive Differential Equations
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作者 XIA Zhinan 《数学理论与应用》 2025年第4期73-86,共14页
In this paper,we utilize the theory of Kurzweil-Henstock integrals to investigate new criteria for boundedness in terms of two measures for generalized ordinary differential equations.As applications,we establish crit... In this paper,we utilize the theory of Kurzweil-Henstock integrals to investigate new criteria for boundedness in terms of two measures for generalized ordinary differential equations.As applications,we establish criteria for(h_(0),h)-uniform boundedness and(h_(0),h)-uniform ultimate boundedness in terms of two measures for impulsive differential equations. 展开更多
关键词 generalized ordinary differential equation impulsive differential equation (h_(0) h)-uniform boundedness (h_(0) h)-uniform ultimate boundedness
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基于机器学习方法的社会融资规模驱动因素
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作者 郝雨桐 钟宁桦 +1 位作者 刘若蕖 沈一帆 《同济大学学报(自然科学版)》 北大核心 2026年第1期160-170,共11页
近年来社会融资规模扩张动能减弱,为厘清其背后的深层成因并探索驱动其增长的有效路径,采用XGBoost算法与2种解释性工具,剖析影响社会融资规模的关键因素,得到比较一致的结论。研究结果表明:消费和投资是社会融资规模增长的关键驱动力... 近年来社会融资规模扩张动能减弱,为厘清其背后的深层成因并探索驱动其增长的有效路径,采用XGBoost算法与2种解释性工具,剖析影响社会融资规模的关键因素,得到比较一致的结论。研究结果表明:消费和投资是社会融资规模增长的关键驱动力。分时间的脉冲响应分析显示,2012年后投资驱动社会融资规模能力逐渐减弱,而消费驱动能力逐渐增强。消费市场疲软是近期拖累社会融资规模增长的主要因素。进一步分析我国不同地区之间的差异,发现消费对社会融资规模的驱动作用具有区域差异,在东部地区效果最强。建议应更好地发挥消费的基础性作用,逐渐形成“以消促投”的良性循环,最终以消费和投资“双轮”驱动社会融资规模稳健增长。 展开更多
关键词 社会融资规模 投资消费 广义脉冲响应 XGBoost
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500 MW冲击式水轮发电机调相及深度进相运行能力分析研究
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作者 刘振东 杨勇 +3 位作者 周胜耕 刘健俊 熊小康 李文博 《水电能源科学》 北大核心 2026年第2期211-215,139,共6页
为分析水轮发电机调相及进相运行在电网电压调节中的作用机制,首先通过理论分析揭示了影响运行性能的关键限制因素,并基于多个水电机组进相试验数据分析运行特性规律;进而以扎拉500 MW冲击式水轮发电机为研究对象,建立仿真模型,系统对... 为分析水轮发电机调相及进相运行在电网电压调节中的作用机制,首先通过理论分析揭示了影响运行性能的关键限制因素,并基于多个水电机组进相试验数据分析运行特性规律;进而以扎拉500 MW冲击式水轮发电机为研究对象,建立仿真模型,系统对比分析了不同运行电压和联系电抗条件下的调相及进相运行能力,仿真结果与理论分析的规律一致。基于研究结果,提出了优化水电机组调相及进相运行的具体建议,为电网电压调节提供了理论依据和实践指导。 展开更多
关键词 冲击式水轮发电机 运行电压 联系电抗 调相 进相深度 限制因素
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Indirect Adaptive Fuzzy and Impulsive Control of Nonlinear Systems
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作者 Hai-Bo Jiang 《International Journal of Automation and computing》 EI 2010年第4期484-491,共8页
The problem of indirect adaptive fuzzy and impulsive control for a class of nonlinear systems is investigated. Based on the approximation capability of fuzzy systems, a novel adaptive fuzzy and impulsive control strat... The problem of indirect adaptive fuzzy and impulsive control for a class of nonlinear systems is investigated. Based on the approximation capability of fuzzy systems, a novel adaptive fuzzy and impulsive control strategy with supervisory controller is developed. With the help of a supervisory controller, global stability of the resulting closed-loop system is established in the sense that all signals involved are uniformly bounded. Furthermore, the adaptive compensation term of the upper bound function of the sum of residual and approximation error is adopted to reduce the effects of modeling error. By the generalized Barbalat's lemma, the tracking error between the output of the system and the reference signal is proved to be convergent to zero Asymptotically. Simulation results illustrate the effectiveness of the proposed approach. 展开更多
关键词 Fuzzy control adaptive control impulsive control generalized Barbalat's lemma.
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Mild Solutions for Nonlocal Impulsive Fractional Semilinear Differential Inclusions with Delay in Banach Spaces
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作者 Ahmed Gamal Ibrahim Nawal Abdulwahab Al Sarori 《Applied Mathematics》 2013年第7期40-56,共17页
In this paper, we give various existence results concerning the existence of mild solutions for nonlocal impulsive differential inclusions with delay and of fractional order in Caputo sense in Banach space. We conside... In this paper, we give various existence results concerning the existence of mild solutions for nonlocal impulsive differential inclusions with delay and of fractional order in Caputo sense in Banach space. We consider the case when the values of the orient field are convex as well as nonconvex. Our obtained results improve and generalize many results proved in recent papers. 展开更多
关键词 FRACTIONAL DIFFERENTIAL INCLUSIONS impulsIVE SEMILINEAR Functional DIFFERENTIAL INCLUSIONS The Infinitesimal generator of a Semigroup NONLOCAL Conditions Mild Solutions
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Analysis of Nonlinear Stochastic Systems with Jumps Generated by Erlang Flow of Events
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作者 Alexander S. Kozhevnikov Konstantin A. Rybakov 《Open Journal of Applied Sciences》 2013年第1期1-7,共7页
In this paper we consider the stochastic systems with jumps (random impulses) generated by Erlang flow of events that lead to discontinuities in paths. These systems may be used in various applications such as a contr... In this paper we consider the stochastic systems with jumps (random impulses) generated by Erlang flow of events that lead to discontinuities in paths. These systems may be used in various applications such as a control of complex technical systems, financial mathematics, mathematical biology and medicine. We propose to use a spectral method formalism to the probabilistic analysis problem for the stochastic systems with jumps. This method allows to get a solution of the analysis problem in an explicit form. 展开更多
关键词 ANALYSIS ERLANG FLOW of EVENTS generalized Fokker-Planck Equations Random impulses JUMP-DIFFUSION Process SPECTRAL Characteristic SPECTRAL Method Formalism Stochastic System
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Impulsive synchronization of two coupled complex networks with time-delayed dynamical nodes
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作者 王树国 姚洪兴 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期136-141,共6页
In this paper, we investigate the impulsive synchronization between two coupled complex networks with time- delayed dynamical nodes. Based on the Lyapunov stability, the linear feedback control and the impulsive contr... In this paper, we investigate the impulsive synchronization between two coupled complex networks with time- delayed dynamical nodes. Based on the Lyapunov stability, the linear feedback control and the impulsive control theories, the linear feedback and the impulsive controllers are designed separately. By using the generalized Barbalat's lemma, the global asymptotic impulsive synchronization of the drive-response complex networks is derived and some corresponding sufficient conditions are also obtained. Numerical examples are presented to verify the effectiveness and the correctness of the synchronization criteria. 展开更多
关键词 complex dynamical networks impulsive synchronization time-delayed nodes general-ized Barbalat lemma
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On Wavelet Transform General Modulus Maxima Metric for Singularity Classification in Mammograms
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作者 Tomislav Bujanovic Ikhlas Abdel-Qader 《Open Journal of Medical Imaging》 2013年第1期17-30,共14页
Continuous wavelet transform is employed to detect singularities in 2-D signals by tracking modulus maxima along maxima lines and particularly applied to microcalcification detection in mammograms. The microcalcificat... Continuous wavelet transform is employed to detect singularities in 2-D signals by tracking modulus maxima along maxima lines and particularly applied to microcalcification detection in mammograms. The microcalcifications are modeled as smoothed positive impulse functions. Other target property detection can be performed by adjusting its mathematical model. In this application, the general modulus maximum and its scale of each singular point are detected and statistically analyzed locally in its neighborhood. The diagnosed microcalcification cluster results are compared with health tissue results, showing that general modulus maxima can serve as a suspicious spot detection tool with the detection performance no significantly sensitive to the breast tissue background properties. Performed fractal analysis of selected singularities supports the statistical findings. It is important to select the suitable computation parameters-thresholds of magnitude, argument and frequency range-in accordance to mathematical description of the target property as well as spatial and numerical resolution of the analyzed signal. The tests are performed on a set of images with empirically selected parameters for 200 μm/pixel spatial and 8 bits/pixel numerical resolution, appropriate for detection of the suspicious spots in a mammogram. The results show that the magnitude of a singularity general maximum can play a significant role in the detection of microcalcification, while zooming into a cluster in image finer spatial resolution both magnitude of general maximum and the spatial distribution of the selected set of singularities may lead to the breast abnormality characterization. 展开更多
关键词 Continuous Wavelet Transform Fractal Dimension generAL MODULUS Maximum MICROCALCIFICATION SINGULARITY Smoothed impulse Function
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基于高解析度CFD-DEM流固耦合算法的滑坡涌浪数值计算模型 被引量:1
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作者 赵兰浩 李荣臻 +1 位作者 毛佳 肖景文 《华北水利水电大学学报(自然科学版)》 北大核心 2025年第6期92-100,共9页
【目的】库岸滑坡涌浪严重威胁库区安全,现有经验公式及传统数值模型难以准确刻画涌浪产生过程中的流体-固体耦合效应。旨在建立一种基于高解析度CFD-DEM流固耦合算法的数值模型,以精确模拟滑坡涌浪全过程。【方法】采用基于欧拉框架的... 【目的】库岸滑坡涌浪严重威胁库区安全,现有经验公式及传统数值模型难以准确刻画涌浪产生过程中的流体-固体耦合效应。旨在建立一种基于高解析度CFD-DEM流固耦合算法的数值模型,以精确模拟滑坡涌浪全过程。【方法】采用基于欧拉框架的计算流体动力学(CFD)模拟流体运动,基于拉格朗日框架的离散元法(DEM)描述滑坡体运动,通过浸入边界法(IBM)处理移动边界与强流固耦合作用,并利用守恒式Level Set方法(CLS)追踪自由界面演变。通过交错迭代实现流体与固体间的高解析度耦合求解。【结果】(1)双颗粒沉降算例验证表明,模型能精确捕捉颗粒尾流效应及“牵引-接触-翻滚”现象,计算结果与文献结果高度吻合。(2)可变形水下滑坡涌浪模拟显示,模型可准确反映稠密块体与流体的相互作用,自由面演化规律与试验数据一致。(3)在Lituya湾实际案例中,模型成功复现了涌浪产生、传播及爬高过程,最大浪高计算值(146 m)与实测值(150 m)误差仅为2.7%。【结论】所提出的高解析度CFD-DEM耦合模型能有效模拟滑坡涌浪中的复杂流固耦合行为,显著优于依赖经验公式的非解析方法,为库区滑坡涌浪灾害风险评估提供了可靠的数值工具。 展开更多
关键词 滑坡涌浪 浸入边界法 计算流体力学 离散元法 守恒式Level Set方法
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基于FLOW3D的V型河道滑坡涌浪首浪高度影响因素分析
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作者 王环玲 冯业林 +2 位作者 粟焕 赵富刚 马行生 《三峡大学学报(自然科学版)》 北大核心 2025年第3期1-6,19,共7页
滑坡涌浪是影响山区水库安全运行的主要威胁之一,研究V型河道滑坡涌浪的首浪特征和影响因素对库区灾害防治有重要意义.本文使用FLOW3D计算流体力学方法对V型河道滑坡涌浪灾害进行了系统研究.建立了V型河道滑坡涌浪计算模型,考虑滑坡体... 滑坡涌浪是影响山区水库安全运行的主要威胁之一,研究V型河道滑坡涌浪的首浪特征和影响因素对库区灾害防治有重要意义.本文使用FLOW3D计算流体力学方法对V型河道滑坡涌浪灾害进行了系统研究.建立了V型河道滑坡涌浪计算模型,考虑滑坡体体积、滑速、河道水深、岸坡倾角、滑床摩擦系数等因素,进行了35组不同工况下的滑坡涌浪数值模拟,获取滑坡入水产生涌浪的过程和首浪高度.将数值模拟结果与经验公式进行了对比,分析不同因素对首浪高度的影响程度.结果表明,河道水深、滑床摩擦系数与首浪高度呈负相关,滑坡体积、入水速度、岸坡倾角与首浪高度呈正相关.各因素对首浪高度的影响程度关系为:入水速度>滑坡体积>岸坡倾角>河道水深>滑床摩擦系数.本文研究为山区水库滑坡涌浪灾害防治提供参考. 展开更多
关键词 滑坡涌浪 首浪高度 敏感性分析 V型河道 FLOW3D
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滑坡涌浪综合防控工程措施研究进展与挑战 被引量:1
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作者 黄波林 殷跃平 +4 位作者 李仁江 蒋树 秦臻 张鹏 闫国强 《工程地质学报》 北大核心 2025年第1期159-170,共12页
滑坡涌浪的研究从科学认识、预测分析走向风险防控是防灾减灾的必然要求。本文以滑坡涌浪演进阶段为线,串联综述了涌浪防控的方法、硬性工程措施及其机制。在滑坡造浪阶段总结了以减少造浪能力为目标的滑坡整治措施;斜坡式、直墙式和浮... 滑坡涌浪的研究从科学认识、预测分析走向风险防控是防灾减灾的必然要求。本文以滑坡涌浪演进阶段为线,串联综述了涌浪防控的方法、硬性工程措施及其机制。在滑坡造浪阶段总结了以减少造浪能力为目标的滑坡整治措施;斜坡式、直墙式和浮式等防波堤类型可适用于传播浪的消减,主要功能为阻挡、反射和耗散涌浪能量;不同类型的防浪墙阻挡爬坡浪的机制不同。根据滑坡状态等条件,滑坡涌浪风险防控可利用回避、保留、转移和损失控制等4种方法来进行,具体措施包括选址规划与整治利用、防治规划与监测预警、涌浪降险消减工程、涌浪预警与应急避险等。阐述了滑坡涌浪风险防控面临的重大挑战,指引滑坡涌浪防控研究向前发展的方向。 展开更多
关键词 造浪能力 防波堤 防浪墙 耗散 涌浪降险消减工程
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偏压对AEG辅助离子渗氮+HiPIMS沉积TiAlSiN涂层组织和力学性能的影响 被引量:1
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作者 曾琨 成永健 +3 位作者 李志荣 胡树兵 罗志明 刘纪元 《材料热处理学报》 北大核心 2025年第1期154-163,共10页
采用AEG(Arc electronic generator)弧光电子发生器辅助渗氮技术在H13(4Cr5MoSiV1)钢表面进行真空离子渗氮,通过X射线衍射仪、扫描电镜和维氏硬度计分析了偏压对渗氮层的微观组织和性能的影响。结果表明:渗氮层的物相主要为含氮马氏体α... 采用AEG(Arc electronic generator)弧光电子发生器辅助渗氮技术在H13(4Cr5MoSiV1)钢表面进行真空离子渗氮,通过X射线衍射仪、扫描电镜和维氏硬度计分析了偏压对渗氮层的微观组织和性能的影响。结果表明:渗氮层的物相主要为含氮马氏体α-Fe(N),随着偏压的增加,α-Fe(N)相向ε-Fe_(3)N相与γ′-Fe_(4)N相转变,渗氮层的厚度也随之增加,直到偏压增加到-600 V时渗氮层被刻蚀下来。在-400 V时,渗氮层的厚度最厚,为90μm,硬度最高约为1300 HV0.1。在-400 V偏压渗氮层的基础上,利用高功率脉冲磁控溅射(HiPIMS)技术沉积TiAlSiN涂层,采用X射线衍射仪、扫描电镜、划痕仪和纳米硬度计等分析了不同偏压下涂层的组织和性能。结果表明:TiAlSiN涂层基本以TiALN(200)相形式存在,随着偏压的增加,Ti元素的比例会增加;涂层的结合力随着偏压的增加而先增加后下降,在-120 V时,临界载荷LN,C2最高为85 N;TiAlSiN涂层的力学性能(H_(IT)/E_(IT)、H_(IT)^(3)/E_(IT)^(2))随着偏压的增加而先增加后下降,在-90 V时H_(IT)/E_(IT)最高约为0.093,H_(IT)^(3)/E_(IT)^(2)最高约为0.275。 展开更多
关键词 离子渗氮 AEG 偏压 HIPIMS TiAlSiN 力学性能
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喷管喉径对火药点火器点火性能影响仿真分析
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作者 朱珂 柳洋 +3 位作者 何昆 李雪飞 张靖宇 董海平 《火箭推进》 北大核心 2025年第5期93-101,110,共10页
为了确保低温条件下某运载火箭燃气发生器火药点火器主装药的点火性能满足要求,基于经典内弹道理论,建立了该发生器火药点火器内弹道燃烧模型及仿真模型,利用MATLAB软件的Simulink模块对内弹道仿真模型进行求解,得到了在低温条件下,喷... 为了确保低温条件下某运载火箭燃气发生器火药点火器主装药的点火性能满足要求,基于经典内弹道理论,建立了该发生器火药点火器内弹道燃烧模型及仿真模型,利用MATLAB软件的Simulink模块对内弹道仿真模型进行求解,得到了在低温条件下,喷管喉径分别为3.2、3.4、3.6、3.8、4.0 mm时火药点火器燃烧室内点火压力-时间曲线,采用Origin软件计算了不同喷管喉径下的点火冲量和压力峰值,得到了点火冲量和压力峰值随喷管喉径而变化的趋势。结合满足该点火器主装药正常点火的临界点火冲量和点火器壳体能承受的最大压力值,确定了该发生器火药点火器喷管喉部直径设计的最佳范围为3.4~3.6 mm。试验表明,仿真结果与试验验证结果基本一致,误差不超过5%。 展开更多
关键词 发生器火药点火器 喷管喉径 点火冲量 压力峰值
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一类分数阶脉冲微分方程组边值问题的研究 被引量:1
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作者 刘龙 吴克晴 王慧慧 《杭州师范大学学报(自然科学版)》 2025年第5期493-502,共10页
研究了一类具有Caputo导数的分数阶脉冲微分方程组的Fredholm边值问题,以及对应的弱扰动线性边值问题.其中边值问题由线性向量泛函指定,其分量的个数与分数阶脉冲微分方程组的维数不相等.通过求解相关齐次系统的通解和非齐次系统的任意... 研究了一类具有Caputo导数的分数阶脉冲微分方程组的Fredholm边值问题,以及对应的弱扰动线性边值问题.其中边值问题由线性向量泛函指定,其分量的个数与分数阶脉冲微分方程组的维数不相等.通过求解相关齐次系统的通解和非齐次系统的任意一个特解,得出该分数阶微分方程组的通解.基于此通解,应用投影理论,构造出该边值问题的一类线性无关解.同时,在齐次生成边值问题的解不唯一且非齐次生成边值问题无解的条件下,确定了弱扰动线性边值问题解的分岔条件.最后,给出一个具体实例来说明主要结论的有效性. 展开更多
关键词 边值问题 分数阶微分方程 脉冲 广义逆矩阵 分岔
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