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Cavitation Diagnostics Based on Self-Tuning VMD for Fluid Machinery with Low-SNR Conditions

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 212-226页

作者： Hao Liu Zheming tong Bingyang Shang Shuiguang tong State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China

Variational mode decomposition(VMD)is a suitable tool for processing cavitation-induced vibration signals and is greatly affected by two parameters:the decomposed number K and penalty factorαunder strong noise *** solve this issue,this study proposed self-tuning VMD(SVMD)for cavitation diagnostics in fluid machinery,with a special focus on low signal-to-noise ratio conditions.A two-stage progressive refinement of the coarsely located target penalty factor for SVMD was conducted to narrow down the search space for accelerated decomposition.A hybrid optimized sparrow search algorithm(HOSSA)was developed for optimalαfine-tuning in a refined space based on fault-type-guided objective *** on the submodes obtained using exclusive penalty factors in each iteration,the cavitation-related characteristic frequencies(CCFs)were extracted for *** power spectrum correlation coefficient between the SVMD reconstruction and original signals was employed as a stop criterion to determine whether to stop further *** proposed SVMD overcomes the blindness of setting the mode number K in advance and the drawback of sharing penalty factors for all submodes in fixed-parameter and parameter-optimized *** with other existing methods in simulation signal decomposition and in-lab experimental data demonstrated the advantages of the proposed method in accurately extracting CCFs with lower computational *** especially enhances the denoising capability of the VMD-based method.

关键词： Fluid machinery Self-tuning VMD Cavitation diagnostics Hybrid optimized sparrow search algorithm

General teleparallel gravity from Finsler geometry

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Communications in Theoretical Physics 2023年第9期75卷 104-112页

作者： Yeheng tong Interdisciplinary Center for Theoretical Study University of Science and Technology of ChinaHefeiAnhui 230026China Peng Huanwu Center for Fundamental Theory HefeiAnhui 230026China

Riemannian geometry, as a basis for general relativity, can be obtained from the more general Finsler geometry in terms of the Cartan connection and Chern connection, as discussed frequently in the literature. However, there are other gravity theories that can be made to be equivalent to general relativity but are based on non-Riemannian geometry. Famous examples are the Teleparallel and Symmetric Teleparallel gravity theories. In this paper, we show how to obtain the geometry for Teleparallel gravity from Finsler geometry in terms of a ‘Teleparallel type’ connection.

关键词： Finsler geometry teleparallel gravity Finsler connection

Limits of One-dimensional Interacting Particle Systems with Two-scale Interaction

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Chinese Annals of Mathematics,Series B 2022年第2期43卷 195-208页

作者： tong ZHAO School of Mathematical Sciences Fudan UniversityShanghai 200433China

This paper characterizes the limits of a large system of interacting particles distributed on the real *** interaction occurring among neighbors involves two kinds of independent actions with different *** system is a generalization of the voter process,of which each particle is of type A or *** suitable scaling,the local proportion functions of A particles converge to continuous functions which solve a class of stochastic partial differential equations driven by Fisher-Wright white *** obtain the convergence,the tightness of these functions is derived from the moment estimate method.

关键词： Interacting particle systems Stochastic partial differential equations Two-scale interaction Tightness

新疆南天山榆树沟含石榴夕线石泥质麻粒岩的超高温变质作用及其构造意义

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岩石学报 2025年第1期41卷 215-236页

作者：荆彦清仝来喜刘兆李超大陆动力学国家重点实验室西北大学地质学系西安710069

天山造山带是中亚造山带的重要组成部分,新疆南天山造山带出露有橄榄岩-麻粒岩地体,其北部榆树沟地区麻粒岩超高温变质作用的确定及P-T-t轨迹的建立为南天山造山带增生造山过程的研究提供了重要依据。本文主要以榆树沟地区3个含石榴夕... 详细信息

天山造山带是中亚造山带的重要组成部分,新疆南天山造山带出露有橄榄岩-麻粒岩地体,其北部榆树沟地区麻粒岩超高温变质作用的确定及P-T-t轨迹的建立为南天山造山带增生造山过程的研究提供了重要依据。本文主要以榆树沟地区3个含石榴夕线石泥质麻粒岩为研究对象,在详细岩相学研究的基础上进行了温压计算、相平衡模拟及锆石U-Pb年龄分析。结果显示其普遍保留了4个阶段的矿物组合:(1)峰前阶段(M1)主要是石榴子石核部与核部包裹体矿物Grt1+Bt1+Pl1+Ilm1+Rt1+Qz1±Ksp1;(2)峰期阶段(M2)由石榴子石幔部和基质矿物核部组成,Grt2+Sil2+Ksp2+Pl2+Ilm2+Rt2+Qz2+Liq2,其温压条件为910~973℃和0.90~1.09GPa;(3)高压麻粒岩相阶段(M3)主要是石榴子石内边部和边部包裹体及基质中矿物的边部,Grt3+Bt3+Sil3+Ksp3+Pl3+Ilm3+Rt3+Qz3+Liq3,其温压结果为845~869℃和1.01~1.14GPa;(4)角闪岩相退变质阶段(M4)以石榴子石的外边部及围绕石榴子石的矿物为代表,Grt4+Bt4+Sil4+Ksp4+Pl4+Ilm4+Qz4±Rt4,其温压条件为701~737℃和0.7~0.8GPa。温压结果指示泥质麻粒岩记录了一条逆时针P-T轨迹。锆石U-Pb年龄分析结果指示原岩沉积是在427Ma之后,超高温变质作用发生在397~409Ma,压力峰期变质作用年龄范围为381~395Ma,退变质年龄结果为355~387Ma。超高温变质作用的热源可能是泥盆纪弧岩浆侵入,随后麻粒岩及与之接触的橄榄岩被俯冲板片捕获并经历了高压变质作用,后期受挤压折返发生了退变质降压冷却。

关键词：泥质麻粒岩超高温变质作用 P-T轨迹榆树沟南天山

Interface of transition metal oxides at the atomic scale

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Science China(Physics,Mechanics & Astronomy) 2016年第9期59卷 1-9页

作者： tong-tong Shang Xin-Yu Liu Lin Gu Beijing National Laboratory Jor Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences Beijing 100190China Collaborative Innovation Center of Quantum Matter Beijing 100190China

Remarkable phenomena arise at well-defined heterostructures, composed of transition metal oxides, which is absent in the bulk counterpart, providing us a paradigm for exploring the various electron correlation effects. The functional properties of such heterostructures have attracted much attention in the microelectronic and renewable energy fields. Exotic and unexpected states of matter could arise from the reconstruction and coupling among lattice, charge, orbital and spin at the interfaces. Aberration-corrected scanning transmission electron microscopy （STEM） is a powerful tool to visualize the lattice structure and electronic structure at the atomic scale. In the present study some novel phenomena of oxide heterostructures at the atomic scale are summarized and pointed out from the perspective of electron microscopy.

关键词： interface transition metal oxides STEM strong correlation

Synthesis, Structure and Geometrical Calculation of a Novel Co-crystal of {[4-Bromo-2-(benzimidazol-2-yl)phenolato][2-(1-butylbenzimidazol-2-yl)phenolato]zinc(Ⅱ)] and Bis[μ-2-(1-butylbenzimidazol-2-yl)phenolato]-1κN^3:2κO;1κO:2κN^3-bis{[2-(1-butylbe

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Chinese Journal of Structural Chemistry 2007年第2期26卷 143-148页

作者： tong Yi-Ping Department of Chemistry Hanshan Normal University Chaozhou 521041 China

The title compound has been synthesized and characterized crystallographicaUy. It is a co-crystal consisting of two different neutral zinc（H） complexes with Hbpbm （Hbpbm = 4- bromo-2-（benzimidazol-2-yl）phenol） and Hnpbm （Hnpbm = 2-（1-butylbenzimidazol-2-yl）phenol）. One is a monomeric mixed-ligand complex of [Zn（bpbm）（npbm）] 1 and the other a dimer of [Zn2（npbm）4] 2 with their ratio of 2：1. Thus the overall formula for the title compound is 21.2. Adjacent 1 and 2 are connected to each other by intermolecular hydrogen bonding interactions in the lattice. The crystal data： monoclinic, space group P21/c, a = 15.0141（12）, b = 20.9941（17）, c = 18.4686（15） A, β = 97.445（2）°, V = 5772.4（8） A^3, Mr= 2429.68, Z = 2, Dc = 1.398 g/cm^3,μ = 1.579 -1 mm , F（000） = 2504, R = 0.0637 and wR = 0.1771 for 6464 observed reflections （I 〉 2σ（I））. The geometrical structure for 1 has also been theoretically optimized and compared with the experimental one.

关键词： zinc complex co-crystal structure 4-bromo-2-(1-butylbenzimidazol-2-yl)phenol 2-(1-butylbenzimidazol-2-yl)phenol

追寻东坡足迹,倾听苏子心声--《念奴娇·赤壁怀古》《赤壁赋》联读教学探索

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黄冈师范学院学报 2025年第1期45卷 52-57页

作者：童志国安徽省铜陵市第十八中学安徽铜陵244121

《念奴娇·赤壁怀古》与《赤壁赋》作为苏轼在豪放词和赋体散文领域的代表作,其在高中语文教学中的价值不容忽视。本研究采用比较式群文联读模式,对这两篇体裁各异但题材与创作背景相似的经典文学作品进行比较阅读教学。经过“感知性阅... 详细信息

《念奴娇·赤壁怀古》与《赤壁赋》作为苏轼在豪放词和赋体散文领域的代表作,其在高中语文教学中的价值不容忽视。本研究采用比较式群文联读模式,对这两篇体裁各异但题材与创作背景相似的经典文学作品进行比较阅读教学。经过“感知性阅读—读出情感”“理解性阅读—读出作者”“思辨性阅读—读出发现”三个阶段的系列教学活动,旨在深度剖析苏轼作品中蕴含的深层心理意涵,解读苏子字里行间隐藏的心灵密码,从而实现对经典文本的持续创新解读与教学,达到使经典作品常读常新、教学方法常教常新的目标。

关键词：《念奴娇·赤壁怀古》《赤壁赋》感知性阅读理解性阅读思辨性阅读高阶思维

Full-duplex two-way AF relaying systems with imperfect interference cancellation in Nakagami-m fading channels

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Science China(Information Sciences) 2021年第8期64卷 143-155页

作者： Jianping tong Caijun ZHONG College of Science Zhejiang University of Technology Department of Information and Communication Engineering Zhejiang University

Full-duplex(FD) two-way relaying has the potential to substantially improve the spectral efficiency of the system, and is regarded as an enabling technology for the next generation wireless communication systems. Nevertheless, the joint effect of residual interference and channel fading condition on the fundamental performance of FD two-way relaying systems remains unclear. Motivated by this, this study considers a general FD two-way amplify-and-forward(AF) relaying system with imperfect interference cancellation in the versatile Nakagami-m fading channels, and presents a detailed analytical investigation on the outage performance of the system. The findings of the paper suggest that the performance of the FD two-way AF relaying system depends heavily on the residual interference strength, fading condition parameter m, and signal-to-noise ratio(SNR). The FD scheme outperforms the half-duplex(HD) two-way relaying counterpart in the low and moderate SNR regime, while becomes inferior in the high SNR regime, owing to strong residual interference. Also, compared to the channel fading condition of the information transmission channels, the impact of the channel fading condition of the interference channel on the system performance is relatively insignificant. Moreover, it is desirable to deploy the FD scheme when the channel fading condition of the information transmission channels is good, since it can effectively alleviate the detrimental effect of residual interference.

关键词： full-duplex two-way relaying Nakagami-m fading outage probability sum throughput

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A 10-bit 500-MS/s Current Steering DAC with Improved Random Layout

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Chinese Journal of Electronics 2020年第1期29卷 73-81页

作者： tong Xingyuan WANG Chaofeng School of Electronics Engineering Xi'an University of Posts and Telecommunications

According to the segmented current steering Digital-to-analog converter(DAC), the influence of current mismatch and output impedance of the current array on the linearity of DAC is discussed by theoretical analysis and derivation. An optimized layout plan for the current source array randomizes all these unit current sources corresponding to each thermometer code, which can significantly reduce the fist-order and second-order systematic mismatch errors in the current source array,and improve the linearity performance of DAC. With the segmented structure of 6 bit thermometer code and 4 bit binary code, a 10-bit DAC is realized in a 0.18-μm CMOS by using the above layout plan. The active area of this DAC is 620μm× 340μm. Operated at 1 V digital supply and 1.8 V analog supply, with 500 MS/s sampling rate, the measured power consumption of this DAC is 14.3 mW. The measurement results show that the Differential nonlinearity(DNL) and the Integral nonlinearity(INL) of the DAC with this random layout scheme are 0.71 LSB and 1.02 LSB. With 500 MS/s sampling rate and 1.465 MHz input frequency, the Spurious free dynamic range(SFDR) and the Effective number of bits(ENOB) are 65.6 dB and 9.2 bit, respectively.

关键词： Digital-to-analog converter Segmented current steering Random layout Nonlinearity