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Autonomous Recommendation of Fault Detection Algorithms for Spacecraft

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 273-275页

作者： Wenbo Li Baoling ning the National Key Laboratory of Science and Technology on Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100094China the School of Data Science and Technology Heilongjiang UniversityHarbin 150001China

Dear Editor, This letter deals with the problem of algorithm recommendation for online fault detection of spacecraft. By transforming the time series data into distributions and introducing a distribution-aware measure, a principal method is designed for quantifying the detectabilities of fault detection algorithms over special datasets.

关键词： fault introducing letter

一种定量地消除波速横向变化影响的三叉震相一维波速结构反演计算方案

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北京大学学报（自然科学版） 2016年第3期52卷 420-426页

作者：李嘉琪王曙光蔡晨宁杰远北京大学地球与空间科学学院北京100871 中国地震局地震预测研究所北京100036 Department of Earth and Planetary Sciences Washington UniversitySaint LouisMO 63130-4899

通过数值模拟分析,定量讨论震源区附近高速异常、接收区附近低速异常以及目标区浅部局地波速异常对三叉震相反演一维波速结构的影响,结果说明波速横向变化在传统的一维波速结构反演中会产生与异常体相同量级的波速异常假象。提出一种借... 详细信息

通过数值模拟分析,定量讨论震源区附近高速异常、接收区附近低速异常以及目标区浅部局地波速异常对三叉震相反演一维波速结构的影响,结果说明波速横向变化在传统的一维波速结构反演中会产生与异常体相同量级的波速异常假象。提出一种借助区域或全球层析成像结果定量地消除波速横向变化对利用三叉震相走时进行一维波速结构反演影响的解决方案。利用射线追踪法进行的测试计算表明,提出的计算方法能有效地消除波速横向变化对计算结果的影响,使得反演结果更接近于真实结构。

关键词：地震反演地球内部结构地幔转换带三叉震相波速污染

Performance enhancement of perovskite solar cells:surface is the key

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Science China Materials 2024年第1期67卷 375-376页

作者： Wenzhuo Li Zhijun ning School of Physical Science and Technology Shanghaitech UniversityShanghai 201210China

Metal halide perovskite solar cells(PSCs)stand out as one of the most promising contenders among photovoltaic technologies for the *** the past decade,PSCs with high power conversion efficiency(PCE)predominantly adopted the normal(ni-p)device ***,a common p-type organic small molecule,Spiro-OMe TAD,which is widely employed at the top layer of n-i-p devices[1],faces issues such as susceptibility to water absorption and poor thermal stability.

关键词： structure stability perovskite

Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

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Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： ning LI Pingzhi FAN Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control

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基于模板识别方法探测断层结构

北京大学学报（自然科学版） 2018年第4期54卷 730-738页

作者：吴梦羽毛淑娟宁杰远唐启家蒋一然北京大学地球与空间科学学院北京100871 Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of Technologycambridge02139 中国地质大学(武汉)地球物理与空间信息学院武汉430074

在模板识别和地震相对定位方法的基础上,提出一种探测断层结构的地震学方法。借用为了发现更多相似地震而在模板识别方法基础上提出的弱模板识别方法,探测与模板地震有空间位置差异的地震,然后根据波形互相关得到的到时差确定新识别出... 详细信息

在模板识别和地震相对定位方法的基础上,提出一种探测断层结构的地震学方法。借用为了发现更多相似地震而在模板识别方法基础上提出的弱模板识别方法,探测与模板地震有空间位置差异的地震,然后根据波形互相关得到的到时差确定新识别出的地震相对于模板地震的空间分布。由于该方法对相似度要求较低,且因计算量小而可以扫描更长时间的地震记录,所以可以探测到更多能够比较精准地刻画断层细结构的微地震。利用渤海湾地区40天的地震波数据,初步证明了这一方法的可行性。

关键词：模板识别方法(MFT) 断层结构地震定位渤海湾微地震

Imprints of ultralight axions on the gravitational wave and pulsar timing measurement

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 23-29页

作者： ning Xie Fa Peng Huang MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

The axion or axion-like particle motivated from a natural solution of strong CP problem or string theory is a promising dark matter *** study the new observational effects of ultralight axion-like particles by the space-borne gravitational wave detector and the radio *** the neutron star-black hole binary as an example,we demonstrate that the gravitational waveform could be obviously modified by the slow depletion of the axion cloud around the black hole formed through the superradiance *** compare these new effects on the binary with the well-studied effects from dynamical friction with dark matter and dipole radiation in model-independent ***,we discuss the constraints from LIGO/Virgo and study the detectability of the ultralight axion particles at LISA and TianQin.

关键词： gravitational wave axion dark matter

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高铁震源地震信号的挤压时频分析应用

地球物理学报 2019年第6期62卷 2328-2335页

作者：王晓凯陈文超温景充宁杰远李嘉琪西安交通大学信息与通信工程学院西安710049 北京大学地球与空间科学学院北京100871 高铁地震学联合研究组北京100029

我国每天有数千趟高铁列车驰骋在纵横交错的高铁线路上,构成了十分理想的均布震源,但寻找适合高铁震源地震信号的处理方法是充分挖掘信息的关键.传统的频谱分析结果表明高铁震源所产生的地震信号具有明显的窄带分立谱特征,但无法精确获... 详细信息

我国每天有数千趟高铁列车驰骋在纵横交错的高铁线路上,构成了十分理想的均布震源,但寻找适合高铁震源地震信号的处理方法是充分挖掘信息的关键.传统的频谱分析结果表明高铁震源所产生的地震信号具有明显的窄带分立谱特征,但无法精确获得高铁震源地震信号的时频变化规律.本文首次将挤压时频分析这种分析工具引入到高铁震源地震信号处理中,对中国南方某高铁沿线采集到的高铁震源地震数据进行了分析.处理结果表明:利用挤压时频分析能够更加精确地刻画频率成分随时间的变化,能够利用单检波器精确刻画高铁列车的运行状态(匀速、加速等);同时利用挤压时频变换还可高精度地重构出所需频带的信号,为提取高铁震源地震信号的特征成分提供了一种有力工具.

关键词：高铁震源地震信号挤压时频分析信号重构

Digital Twin Technology of Human-Machine Integration in Cross-Belt Sorting System

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 195-212页

作者： Yanbo Qu ning Zhao Haojue Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Institute of Microelectronics of the Chinese Academy of Sciences Beijing 100029China Wayzim Technology Co. LtdWuxi 214108China Business School Beijing Technology and Business UniversityBeijing 100048China

The Chinese express delivery industry processes nearly 110 billion items in 2022,averaging an annual growth rate of 200%.Among the various types of sorting systems used for handling express items,cross-belt sorting systems stand out as the most ***,despite their high degree of automation,the workload for operators has intensified owing to the surging volume of express *** the era of Industry 5.0,it is imperative to adopt new technologies that not only enhance worker welfare but also improve the efficiency of cross-belt *** a balance between efficiency in handling express items and operator well-being is *** twin technology offers a promising solution in this respect.A realization method of a human-machine integrated digital twin is proposed in this study,enabling the interaction of biological human bodies,virtual human bodies,virtual equipment,and logistics equipment in a closed loop,thus setting an operating *** technologies in the proposed framework include a collection of heterogeneous data from multiple sources,construction of the relationship between operator fatigue and operation efficiency based on physiological measurements,virtual model construction,and an online optimization module based on real-time *** feasibility of the proposed method was verified in an express distribution center.

关键词： Industry 5.0 Cross-belt sorting system Human-machine integrated Digital twin Online optimization

Flocking Effects of the Stochastic Cucker-Smale System with Noise

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Journal of Systems Science & Complexity 2024年第5期37卷 1978-1994页

作者： HAN ning GE Bin LI Lin School of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China

In this paper,the flocking behavior of a Cucker-Smale model with a leader and noise is studied in a finite *** authors present a Cucker-Smale system with two nonlinear controls for a complex network with stochastic synchronization in *** on the finite-time stability theory of stochastic differential equations,the sufficient conditions for the flocking of stochastic systems in a finite time are obtained by using the Lyapunov function ***,the numerical simulation of the particle system is carried out for the leader and noise,and the correctness of the results is verified.

关键词： Cucker-Smale model flocking behavior leader noise