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Innovation Analysis Approach to Design Parameters of High Speed Train Carriage and Their Intrinsic Complexity Relationships

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1091-1100页

作者： Shou-Ne Xiao Ming-Meng Wang guang-zhong Hu guang-Wu Yang State Key Laboratory of Traction Power Southwest Jiaotong University School of Mechanical Engineering Sichuan University of Science & Engineering

In view of the problem that it＇s difficult to accurately grasp the influence range and transmission path of the vehicle top design requirements on the underlying design parameters. Applying directed-weighted complex network to product parameter model is an important method that can clarify the relationships between product parameters and establish the top-down design of a product. The relationships of the product parameters of each node are calculated via a simple path searching algorithm, and the main design parameters are extracted by analysis and comparison. A uniform definition of the index formula for out-in degree can be provided based on the analysis of out- in-degree width and depth and control strength of train carriage body parameters. Vehicle gauge, axle load, crosswind and other parameters with higher values of the out-degree index are the most important boundary condi- tions; the most considerable performance indices are the parameters that have higher values of the out-in-degree index including torsional stiffness, maximum testing speed, service life of the vehicle, and so on; the main design parameters contain train carriage body weight, train weight per extended metre, train height and other parameters with higher values of the in-degree index. The network not only provides theoretical guidance for exploring the relationship of design parameters, but also further enriches the appli- cation of forward design method to high-speed trains.

关键词： Train carriage body parameters Complexnetwork Width influence Depth influence Parametercontrol strength

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Experimental demonstration of suppressing residual geometric dephasing

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Science Bulletin 2019年第23期64卷 1757-1763页

作者： Jin-Ming Cui Ming-zhong Ai Ran He zhong-Hua Qian Xiao-Ke Qin Yun-Feng Huang Zheng-Wei Zhou Chuan-Feng Li Tao tu guang-Can Guo CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Center For Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Luoyang Institute of Electro-Optical Equipment AVICLuoyang 471000China

The geometric phase is regarded as a promising strategy in fault tolerance quantum information processing(QIP) domain due to its phase only depending on the geometry of the path executed. However, decoherence caused by environmental noise will destroy the geometric phase. Traditional dynamic decoupling sequences can eliminate dynamic dephasing but can not reduce residual geometric dephasing, which is still vital for high-precision quantum manipulation. In this work, we experimentally demonstrate effective suppression of residual geometric dephasing with modified dynamic decoupling schemes,using a single trapped171 Ybtion. The experimental results show that the modified schemes can reduce dephasing rate up to more than one order of magnitude compared with traditional dynamic decoupling schemes, where residual geometric dephasing dominates. Besides, we also investigate the impact of intensity and correlation time of the low-frequency noise on coherence of the quantum system. And we confirm these methods can be used in many cases.

关键词： Geometric dephasing Berry phase Dynamic decoupling Ion trap

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Analysis of Venezuela's oil-oriented economy: from the perspective of entropy

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Petroleum Science 2018年第1期15卷 200-209页

作者： Xian-zhong Mu guang-Wen Hu Institute of Circular Economy Beijing University of Technology

To investigate the efficiency and stability of Venezuela＇s oil-oriented economy, this paper applied entropy to the *** on this method, Venezuela＇s oil-centered industry, inefficient regulatory system, and insensitive response to external changes are recognized as an increase in the country＇s entropy. According to these facts, a dissipative structure model is constructed to analyze the efficiency and stability of the Venezuela＇s economic system. The results show that financial assistants（fund flow）, policy reform（policy flow）, and advanced technology（technology flow） can perform as negative entropy inflows（NEIFs）. These NEIFs will promote a series of influence and feedback reactions, which will contribute to recovering Venezuela＇s system efficiency and stability.

关键词： Venezuela Oil-oriented economy system Resource curse Entropy Dissipative structure

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Investigation of the dynamic characteristics of a dual rotor system and its start-up simulation based on finite element method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第4期14卷 268-280页

作者： zhong-xiu FEI Shui-guang TONG Chao WEI Institute of Chemical Machinery Engineering Zhejiang University Mechanical Design Institute Zhejiang University Institute of Thermal Engineering and Power Systems Zhejiang University

Recently,the finite element method(FEM) has been commonly applied in the engineering analysis of rotor *** moments,rotary inertia,transverse shear deformation and gravity can be included in computational models of rotor-bearing *** this paper,a finite element model and its solution method are presented for the calculation of the dynamics of dual rotor systems.A typical structure with two rotor shafts is discussed and the procedure for obtaining the coupling motion equations of the subsystems is illustrated.A computer program is developed to solve critical speeds and to simulate the transient *** influence of gyroscopic moments on co-rotation and counter-rotation is analyzed,and the effect of the speed ratio on critical speed is *** dynamic characteristics under different conditions of increasing speed during start-up are demonstrated by comparison with transient nodal *** presented model provides a complete foundation for further investigation of the dynamics of dual rotor systems.

关键词： Dual rotor system Critical speed Transient response Finite element method(FEM)

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REEs recovery from molten salt electrolytic slag:Challenges and opportunities for environmentally friendly techniques

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Journal of Rare Earths 2024年第6期42卷 1009-1019,I0001页

作者： Ziyan Yang Faxin Xiao Shuchen Sun Heng zhong Ganfeng tu School of Metallurgy Northeastern UniversityShenyang110819China Key Laboratory for Recycling of Nonferrous Metal Resources(Shenyang) Shenyang110819China

Due to the unique physical and chemical properties,rare earth elements(REEs)play a significant role in the high-tech *** the past few decades,the rare earth reserve in China has been gradually decreasing and more pressure has been exerted on the global rare earth supply for the increasing demand of REEs,which indicates that it is essential to recycle secondary resources to meet the rare earth *** for rare earth molten salt electrolytic slag(REMES),although its high rare earth content has potential huge economic value,its high fluorine content of approximately 10 wt%-20 wt%can pollute the *** methods are used to treat *** metallurgical and pyro-hydrometallurgical methods have gotten a big success for solving most of the hydrometallurgical problems,while some problems,like long route and waste water,need to be *** distillation is a new and promising method with a short process due to its harmlessness and high efficiency,but has shortcomings such as high energy consumption and material *** review presents these above three treatment methods,and the challenges and chances of using the recovery technique of REMES in an environmentally friendly way.

关键词： Rare earths Molten salt electrolytic slag Hydrometallurgy Pyro-hydrometallurgy Vacuum distillation Recovery

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理论研究IIB族金属二氢化物分子的基态性质

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原子与分子物理学报 2025年第3期42卷 1-7页

作者：张志鹏杨培龙涂喆研李仁忠西安工程大学理学院西安710048 西安工程大学环境与化学工程学院西安710048

基于小核能量一致性相对论赝势,采用密度泛函理论和耦合簇理论,分别在标量和二分量水平上计算研究了MH_(2)(M=Zn,Cd,Hg,Cn)分子的平衡键长和振动频率.计算结果显示,HgH_(2)和CnH_(2)的自旋轨道耦合效应较为明显.采用的8种泛函总体较好... 详细信息

基于小核能量一致性相对论赝势,采用密度泛函理论和耦合簇理论,分别在标量和二分量水平上计算研究了MH_(2)(M=Zn,Cd,Hg,Cn)分子的平衡键长和振动频率.计算结果显示,HgH_(2)和CnH_(2)的自旋轨道耦合效应较为明显.采用的8种泛函总体较好地评估了自旋轨道耦合效应.耦合簇理论计算的ZnH_(2)、CdH_(2)、HgH_(2)的键长和Σ_(u)振动频率与实验值偏差略大,这可能是由于其多参考态特性较明显.二分量PBE泛函计算的键长和Σ_(u)振动频率与实验值最接近.目前最重的CnH_(2)相关研究未见报道,研究给出了其键长和振动频率的理论值.

关键词：金属二氢化物密度泛函理论耦合簇理论标量相对论自旋轨道耦合

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Isothermal reduction of titanomagnetite concentrates containing coal

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 131-137页

作者： tu Hu Xue-wei Lü Chen-guang Bai Gui-bao Qiu College of Materials Science and Engineering Chongqing University Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology

The isothermal reduction of the Panzhihua titanomagnetite concentrates （PTC） briquette containing coal under argon atmosphere was investigated by thermogravimetry in an electric resistance furnace within the temperature range of 1250-1350°C. The samples reduced in argon at 1350°C for different time were examined by X-ray diffraction （XRD） analysis. Model-fitting and model-free methods were used to evaluate the apparent activation energy of the reduction reaction. It is found that the reduction rate is very fast at the early stage, and then, at a later stage, the reduction rate becomes slow and decreases gradually to the end of the reduction. It is also observed that the reduction of PTC by coal depends greatly on the temperature. At high temperatures, the reduction degree reaches high values faster and the final value achieved is higher than at low temperatures. The final phase composition of the reduced PTC-coal briquette consists in iron and fer-rous-pseudobrookite （FeTi2O5）, while Fe2.75Ti0.25O4, Fe2.5Ti0.5O4, Fe2.25Ti0.75O4, ilmenite （FeTiO3） and wustite （FeO） are intermediate products. The reaction rate is controlled by the phase boundary reaction for reduction degree less than 0.2 with an apparent activation energy of about 68 kJ·mol-1 and by three-dimensional diffusion for reduction degree greater than 0.75 with an apparent activation energy of about 134 kJ·mol-1. For the reduction degree in the range of 0.2-0.75, the reaction rate is under mixed control, and the activation energy increases with the increase of the reduction degree.

关键词： titanomagnetite carbothermal reduction thermogravimetric analysis kinetics

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NS Condition of Admissibility for the Linear Estimator of Normal Mean with Unknown Variance

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1083-1086页

作者： Xing zhong XU Qi guang WU Beijing Institute of Technology Beijing 100081 P. R. China Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China

Suppose Y - N（β, σ^2 In）, where β ∈ R^n and σ^2 〉 0 are unknown. We study the admissibility of linear estimators of mean vector under a quadratic loss function. A necessary and sufficient condition of the admi... 详细信息

关键词： Multivariate normal distribution Mean vector Linear estimator Admissibility

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Propagation of a Rectangular Pulse in an Anomalous Dispersive Medium

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Communications in Theoretical Physics 2002年第8期38卷 224-226页

作者： HUANG Chao-guang ZHANG Yuan-zhong Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918 Beijing 100039 China Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China Institute of Theoretical Physics the Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China CCAST (World Laboratory) P.O. Box 8730 Beijing 100080 China

The pulse with a rectangular envelop propagating through the caesium vapour with two gain lines used inthe Wang, Kuzmich, and Dogariu [Nature (London) 406 (2000) 277] experiment is studied. It is shown that there exis... 详细信息

关键词： propagation of rectangular pulse, anomalous dispersive medium

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An Interpretable Denoising Layer for Neural Networks Based on Reproducing Kernel Hilbert Space and its Application in Machine Fault Diagnosis

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 104-114页

作者： Baoxuan Zhao Changming Cheng Guowei tu Zhike Peng Qingbo He guang Meng State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

Deep learning algorithms based on neural networks make remarkable achievements in machine fault diagnosis,while the noise mixed in measured signals harms the prediction accuracy of *** denoising methods in neural networks,such as using complex network architectures and introducing sparse techniques,always suffer from the difficulty of estimating hyperparameters and the lack of physical *** address this issue,this paper proposes a novel interpretable denoising layer based on reproducing kernel Hilbert space(RKHS)as the first layer for standard neural networks,with the aim to combine the advantages of both traditional signal processing technology with physical interpretation and network modeling strategy with parameter *** investigating the influencing mechanism of parameters on the regularization procedure in RKHS,the key parameter that dynamically controls the signal smoothness with low computational cost is selected as the only trainable parameter of the proposed ***,the forward and backward propagation algorithms of the designed layer are formulated to ensure that the selected parameter can be automatically updated together with other parameters in the neural ***,exponential and piecewise functions are introduced in the weight updating process to keep the trainable weight within a reasonable range and avoid the ill-conditioned *** studies verify the effectiveness and compatibility of the proposed layer design method in intelligent fault diagnosis of machinery in noisy environments.

关键词： Machine fault diagnosis Reproducing kernel Hilbert space(RKHS) Regularization problem Denoising layer Neural network

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