So far quite a few ultraluminous X-ray(ULX) pulsars have been discovered.In this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on th...So far quite a few ultraluminous X-ray(ULX) pulsars have been discovered.In this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on their observed spin-up variations and luminosities.We obtain two branches of dipole magnetic field solutions.They are distributed in the range of B-(0.156-64.5) × 10^(10) G and-(0.275-79.0) × 10^(13) G corresponding to the low-and high-B solutions respectively.The low magnetic field solutions correspond to the state that the neutron stars are far away from the spin equilibrium,and the high magnetic field solutions are close to the spin equilibrium.The ultra-strong magnetic fields derived in Be-type ULX pulsars imply that the accretion mode in Be-type ULX pulsars could be more complicated than in the persistent ULX pulsars and may not be accounted for by the magnetized accretion disk model.We suggest that the transition between the accretor and the propeller regimes may be used to distinguish between the low-and high-B magnetic field solutions in addition to the detection of the cyclotron resonance scattering features.展开更多
针对X-Y平台中模型误差和扰动未知等问题,本文以夹胶玻璃自动切膜为应用背景,设计自动切膜恒力控制系统,并对系统中的交互力进行分析与建模。提出了一种改进线性自抗扰(linear active disturbance rejection controller,LADRC)力控制器...针对X-Y平台中模型误差和扰动未知等问题,本文以夹胶玻璃自动切膜为应用背景,设计自动切膜恒力控制系统,并对系统中的交互力进行分析与建模。提出了一种改进线性自抗扰(linear active disturbance rejection controller,LADRC)力控制器,将滑模控制嵌入到基于预报的线性跟踪微分器(tracking differentiator,TD)中,平衡滤波与相位滞后间的矛盾,利用分数阶比例微分(fractional order proportion differentiation,FOPD)快速响应跟踪力误差,并通过Lyapunov函数对改进线性跟踪微分器进行稳定性证明。通过与线性自抗扰进行比较,对所设计的控制器进行了仿真分析与实验验证。实验结果表明,当玻璃位置等参数发生变化时,基于改进跟踪微分器的线性自抗扰控制系统仍能较好地实现对切刀的交互力控制,有效保证切膜效果,证明了提出方法的有效性与实用性。展开更多
The increased use of rechargeable batteries in portable electronic devices and the continuous develop-ment of novel applications （e.g. transportation and large scale energy storage）, have raised a strong de-mand for...The increased use of rechargeable batteries in portable electronic devices and the continuous develop-ment of novel applications （e.g. transportation and large scale energy storage）, have raised a strong de-mand for high performance batteries with increased energy density, cycle and calendar life, safety andlower costs. This triggers significant efforts to reveal the fundamental mechanism determining batteryperformance with the use of advanced analytical techniques. However, the inherently complex character-istics of battery systems make the mechanism analysis sophisticated and difficult. Synchrotron radiationis an advanced collimated light source with high intensity and tunable energies. It has particular ad-vantages in electronic structure and geometric structure （both the short-range and long-range structure）analysis of materials on different length and time scales. In the past decades, synchrotron X-ray tech-niques have been widely used to understand the fundamental mechanism and guide the technologicaloptimization of batteries. In particular, in situ and operando techniques with high spatial and temporalresolution, enable the nondestructive, real time dynamic investigation of the electrochemical reaction,and lead to significant deep insights into the battery operation mechanism. This review gives a brief introduction of the application of synchrotron X-ray techniques to the inves-tigation of battery systems. The five widely implicated techniques, including X-ray diffraction （XRD）, PairDistribution Function （PDF）, Hard and Soft X-ray absorption spectroscopy （XAS） and X-ray photoelectronspectroscopy （XPS） will be reviewed, with the emphasis on their in situ studies of battery systems during cycling.展开更多
在机会网络中,网络拓扑结构动态变化,节点之间间歇性连接,这种间歇性连接是由于缺乏网络基础设施和终端设备随机移动所造成的,机会网络的这些特性使得路由算法的设计成为一项具有挑战性的研究课题.本文提出一种基于无监督学习模型X-Mean...在机会网络中,网络拓扑结构动态变化,节点之间间歇性连接,这种间歇性连接是由于缺乏网络基础设施和终端设备随机移动所造成的,机会网络的这些特性使得路由算法的设计成为一项具有挑战性的研究课题.本文提出一种基于无监督学习模型X-Means的机会网络路由算法XMROP(Opportunistic network routing algorithm based on unsupervised learning model X-Means),致力于利用机器学习模型来做出路由决策.该路由算法提出新的聚类模型应用模式,解决现阶段机会网络中应用聚类模型所存在的问题,综合考虑连接强度、节点活跃度、缓存等属性特征,定义新的节点中心度度量来衡量节点活跃程度,使用X-Means聚类模型对样本数据集进行训练,以适应机会网络拓扑结构的动态变化,提升路由算法性能.仿真实验结果表明,与KROP,DBSCAN-R,Prophet路由算法相比,XMROP具有更好的性能,从而验证了研究方案的有效性.展开更多
基金supported by the National Key Research and Development Program of China (2016YFA0400803)the National Natural Science Foundation of China under grant Nos.11773015 and 10241301Project U1838201 supported by NSFC and CAS。
文摘So far quite a few ultraluminous X-ray(ULX) pulsars have been discovered.In this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on their observed spin-up variations and luminosities.We obtain two branches of dipole magnetic field solutions.They are distributed in the range of B-(0.156-64.5) × 10^(10) G and-(0.275-79.0) × 10^(13) G corresponding to the low-and high-B solutions respectively.The low magnetic field solutions correspond to the state that the neutron stars are far away from the spin equilibrium,and the high magnetic field solutions are close to the spin equilibrium.The ultra-strong magnetic fields derived in Be-type ULX pulsars imply that the accretion mode in Be-type ULX pulsars could be more complicated than in the persistent ULX pulsars and may not be accounted for by the magnetized accretion disk model.We suggest that the transition between the accretor and the propeller regimes may be used to distinguish between the low-and high-B magnetic field solutions in addition to the detection of the cyclotron resonance scattering features.
文摘针对X-Y平台中模型误差和扰动未知等问题,本文以夹胶玻璃自动切膜为应用背景,设计自动切膜恒力控制系统,并对系统中的交互力进行分析与建模。提出了一种改进线性自抗扰(linear active disturbance rejection controller,LADRC)力控制器,将滑模控制嵌入到基于预报的线性跟踪微分器(tracking differentiator,TD)中,平衡滤波与相位滞后间的矛盾,利用分数阶比例微分(fractional order proportion differentiation,FOPD)快速响应跟踪力误差,并通过Lyapunov函数对改进线性跟踪微分器进行稳定性证明。通过与线性自抗扰进行比较,对所设计的控制器进行了仿真分析与实验验证。实验结果表明,当玻璃位置等参数发生变化时,基于改进跟踪微分器的线性自抗扰控制系统仍能较好地实现对切刀的交互力控制,有效保证切膜效果,证明了提出方法的有效性与实用性。
基金the National Natural Science Foundation of China (Grant nos.21233004,21303147 and 21473148,etc.)the National Key Research and Development Program (Grant no.2016YFB0901500)
文摘The increased use of rechargeable batteries in portable electronic devices and the continuous develop-ment of novel applications （e.g. transportation and large scale energy storage）, have raised a strong de-mand for high performance batteries with increased energy density, cycle and calendar life, safety andlower costs. This triggers significant efforts to reveal the fundamental mechanism determining batteryperformance with the use of advanced analytical techniques. However, the inherently complex character-istics of battery systems make the mechanism analysis sophisticated and difficult. Synchrotron radiationis an advanced collimated light source with high intensity and tunable energies. It has particular ad-vantages in electronic structure and geometric structure （both the short-range and long-range structure）analysis of materials on different length and time scales. In the past decades, synchrotron X-ray tech-niques have been widely used to understand the fundamental mechanism and guide the technologicaloptimization of batteries. In particular, in situ and operando techniques with high spatial and temporalresolution, enable the nondestructive, real time dynamic investigation of the electrochemical reaction,and lead to significant deep insights into the battery operation mechanism. This review gives a brief introduction of the application of synchrotron X-ray techniques to the inves-tigation of battery systems. The five widely implicated techniques, including X-ray diffraction （XRD）, PairDistribution Function （PDF）, Hard and Soft X-ray absorption spectroscopy （XAS） and X-ray photoelectronspectroscopy （XPS） will be reviewed, with the emphasis on their in situ studies of battery systems during cycling.
文摘在机会网络中,网络拓扑结构动态变化,节点之间间歇性连接,这种间歇性连接是由于缺乏网络基础设施和终端设备随机移动所造成的,机会网络的这些特性使得路由算法的设计成为一项具有挑战性的研究课题.本文提出一种基于无监督学习模型X-Means的机会网络路由算法XMROP(Opportunistic network routing algorithm based on unsupervised learning model X-Means),致力于利用机器学习模型来做出路由决策.该路由算法提出新的聚类模型应用模式,解决现阶段机会网络中应用聚类模型所存在的问题,综合考虑连接强度、节点活跃度、缓存等属性特征,定义新的节点中心度度量来衡量节点活跃程度,使用X-Means聚类模型对样本数据集进行训练,以适应机会网络拓扑结构的动态变化,提升路由算法性能.仿真实验结果表明,与KROP,DBSCAN-R,Prophet路由算法相比,XMROP具有更好的性能,从而验证了研究方案的有效性.
