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Journal of Hainan Medical University 2018年第5期24卷 83-86页

作者： Yong-Chao Zhang Bin Xiao quan-hu ge Ran Chen Zhi-Wen Cai Bo Yang Zhi-hua Chen Department of Ultrasound Renmin HospitalHubei University of MedicineShiyan 442000HubeiChina

Objective: The azoospermia is increasingly becoming prevalent year by year,which has been plaguing a great number of infertile couples. Testes biopsy is a gold index to evaluate the testicular spermatogenesis in patients with anspermia. However, it is more invasive and may not accurately reflect the whole spermatogenic function of the testes. In recent years, with the continuous development of ultrasound and assisted reproductive technology, real-time sonoelastography has been widely applied in the evaluation of spermatogenic function in patients with azoospermia. It is still at the initial stage, but shows good application prospects. In this paper, we will summarize and review the present status of male infertility and the clinical application and research progress of real-time sonoelastography in the evaluation of the testicular spermatogenic function of non-obstructive azoospermia patients.

关键词： Real-time sonoelastography Non-obstructive azoospermia Testicular spermatogenesis

A Note on Integral Structures in Some Locally Algebraic Representations of GL_(2)

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Acta Mathematica Sinica,English Series 2021年第1期37卷 59-72页

作者： Yong quan hu Morningside Center of Mathematics Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190P.R.China Chinese Academy of Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China

In the p-adic local Langlands correspondence for GL2(Qp),the following theorem of Berger and Breuil has played an important role:the locally algebraic representations of GL2(Qp)associated to crystabelline Galois representations admit a unique unitary *** this note,we give a new proof of the weaker statement that the locally algebraic representations admit at most one unitary completion and such a completion is automatically *** proof is purely representation theoretic,involving neither(ψ,Γ)-module techniques nor global *** F is a finite extension of Qp,we also get a simpler proof of a theorem of Vignéras for the existence of integral structures for(locally algebraic)special series and for(smooth)tamely ramified principal series.

关键词： Invariant norm diagram

1D Ceria Nanomaterials:Versatile Synthesis and Bio-application

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Journal of Materials Science & Technology 2015年第6期31卷 645-653页

作者： Xueying ge Zhenxing Li quan Yuan Key Laboratory of Analytical Chemistry for Biology and Medicine College of Chemistry and Molecular ScienceMinistry of EducationWuhan University New Energy Research Institute China University of Petroleum

Ceria has emerged as a fascinating and lucrative material in bio-application,for instance,disease treatment,bioimaging and drug delivery due to its abilities of transforming oxidation states between Ce4+and Ce3+and scavenging free radicals,which can produce biological effect,such as being potentially antioxidant towards reactive oxygen ***,many studies about one dimension（ID） CeO2nanomaterials have received much attention because of the unique properties of their length and aspect *** highlight here current research activities focused on the bio-application of 1D ceria *** synthesis methods of 1D cerium oxide nanomaterials were *** synthesis routes,including template,hydrothermal,sonochemical and other methods,were then discussed with examples developed by recent *** differences among these methods were also *** review provides a comprehensive introduction to the synthesis of 1D ceria,its potential applications in biological fields and perspectives on this exciting realm.

关键词： Ceria One dimension Template method Hydrothermal m

Late Cretaceous Aquatic Angiosperms from Jiayin,Heilongjiang,Northeast China

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Acta geologica Sinica(English Edition) 2008年第6期82卷 1133-1140页

作者： quan Cheng SUN ge Research Center of Paleontology ＆ Stratigraphy Jilin University Changchun Jilin 130026 China Key-Lab for Evolution of Past Life and Environment in NE Asia Ministry of Education Changchun Jilin 130026 China Paleontological Institute of Shenyang Normal University Shenyang Jilin 110034 China

Three taxa of Late Cretaceous aquatic angiosperms, Queruexia angulata （Lesq.） Krysht., Cobbania corrugata （Lesq.） Stockey et al. and Nelumbites cf. extenuinervis Upchurch et al. from Jiayin of Heilongjiang, NE China, are described in detail. Among them, Cobbania and Nelumbites from the Upper Cretaceous in China are reported for the first time. The aquatic angiosperm assemblage of Queruexia-Cobbania-Nelumbites appears to imply a seasonal, warm and moist environment in the Jiayin area during the Santonian-Campanian time.

关键词： aquatic angiosperm Late Cretaceous Jiayin Heilongjiang environment

Research on Energy Efficiency Characteristics of Mining Shovel Hoisting and Slewing System Driven by Hydraulic-Electric Hybrid System

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 197-211页

作者： Xiangyu Wang Lei ge Yunhua Li Long quan College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Mining shovel is a crucial piece of equipment for high-efficiency production in open-pit mining and stands as one of the largest energy consumption sources in ***,substantial energy waste occurs during the descent of the hoisting system or the deceleration of the slewing *** reduce the energy loss,an innovative hydrau-lic-electric hybrid drive system is proposed,in which a hydraulic pump/motor connected with an accumulator is added to assist the electric motor to drive the hoisting system or slewing platform,recycling kinetic and potential *** utilization of the kinetic and potential energy reduces the energy loss and installed power of the min-ing ***,the reliability of the mining shovel pure electric drive system also can be *** this paper,the hydraulic-electric hybrid driving principle is introduced,a small-scale testbed is set up to verify the feasibil-ity of the system,and a co-simulation model of the proposed system is established to clarify the system operation and energy *** test and simulation results show that,by adopting the proposed system,compared with the traditional purely electric driving system,the peak power and energy consumption of the hoisting electric motor are reduced by 36.7%and 29.7%,***,the slewing electric motor experiences a significant decrease in peak power by 86.9%and a reduction in energy consumption by 59.4%.The proposed system expands the application area of the hydraulic electric hybrid drive system and provides a reference for its application in over-sized and super heavy equipment.

关键词： Mining shovel Hoisting and slewing system Hydraulic-electric hybrid drive Energy saving

Ambient aerobic pretreatment enhances food waste fermentation broth for high content perchlorate biodegradation

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Progress in Natural Science:Materials International 2023年第6期33卷 891-900页

作者： Lijie Cheng Ningbo Gao Zhiqiang ge Cui quan School of Energy and Power Engineering Xi'an Jiaotong University Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace

The biodegradation of perchlorate(ClO4-) in contaminated environments often requires extra electron donors and carbon *** study investigates the use of ambient aerobic pretreatment technology combined with anaerobic fermentation of food waste to produce fermentation broth of food waste(FBFW) and enhance ClO4-biodegradation *** results demonstrated that FBFW,prepared through aerobic pretreatment,exhibited excellent performance in *** an electron donor-to-acceptor ratio of 1.2,a remarkable ClO4-removal efficiency of 92.38% was achieved at 72 h when using FBFW after a 6-day aerobic *** can be attributed to the higher proportion of lactic acid and lower ammonium ***,FBFW,serving as an electron donor and carbon source after aerobic pretreatment,enhanced the abundance of microbial taxa belonging to Firmicutes and Aeromonas,known for their involvement in electron transfer and reduction processes related to ClO4-.This study highlighted the potential of aerobic pretreatment of food waste combined with anaerobic fermentation to produce FBFW and enhance ClO4-reduction,offering new perspectives for food waste utilization and the remediation of high ClO4-contamination.

关键词： Ambient aerobic pretreatment Food waste Perchlorate biodegradation Lactic acid Ammonium

Initial costates derived by near-optimal reference sequence and least-squares method

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Chinese Journal of Aeronautics 2024年第5期37卷 377-391页

作者： Shaozhao LU Yao ZHANG quan hu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

In this paper,we present a novel initial costates solver for initializing time-optimal trajectory problems in relative motion with continuous low *** proposed solver consists of two primary components:training a Multilayer Perceptron(MLP)for generating reference sequence and Time of Flight(TOF)to the target,and deriving a system of linear algebraic equations for obtaining the initial *** overcome the challenge of generating training samples for the MLP,the backward generation method is proposed to obtain five different training *** training database and sample form are determined by analyzing the input and output correlation using the Pearson correlation *** best-performing MLP is obtained by analyzing the training results with various hyper-parameter combinations.A reference sequence starting from the initial states is obtained by integrating forward with the near-optimal control vector from the output of ***,a system of linear algebraic equations for estimating the initial costates is derived using the reference sequence and the necessary conditions for *** results demonstrate that the proposed initial costates solver improves the convergence ratio and reduce the function calls of the shooting ***,Monte-Carlo simulation illustrates that the initial costates solver is applicable to different initial velocities,demonstrating excellent generalization ability.

关键词： Relative motion Expanding training database Multilayer perceptron Initial costates Least-squares method

On Submanifolds Whose Tubular Hypersurfaces Have Constant Higher Order Mean Curvatures

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Acta Mathematica Sinica,English Series 2016年第4期32卷 474-498页

作者： Tian Shou JIN Jian quan ge Information and Control Engineering Institute ZheJiang Guangsha College of Applied Construction Technology School of Mathematical Sciences Laboratory of Mathematics and Complex SystemsBeijing Normal University

Motivated by the theory of isoparametric hypersurfaces,we study submanifolds whose tubular hypersurfaces have some constant higher order mean *** a k-th order mean curvature Q_k^v（k ≥ 1） of a submanifold M^n-is defined as the k-th power sum of the principal curvatures,or equivalently,of the shape operator with respect to the unit normal vector *** show that if all nearby tubular hypersurfaces of M have some constant higher order mean curvatures,then the submanifold M itself has some constant higher order mean curvatures Q_k^v independent of the choice of *** identities involving higher order mean curvatures and Jacobi operators on such submanifolds are also *** particular,we generalize several classical results in isoparametric theory given by ***,***,***,***,et *** an application,we finally get a geometrical filtration for the focal submanifolds of isoparametric functions on a complete Riemannian manifold.

关键词： Isoparametric hypersurface constant mean curvature austere submanifold

Grain size distribution and topology in 3D grain growth simulation with large-scale Monte Carlo method

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 37-42页

作者： Hao Wang Guo-quan Liu Xiang-ge Qin School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Jiamusi University Jiamusi 154007 China

Three-dimensional normal grain growth was appropriately simulated using a Potts model Monte Carlo algorithm. The quasi-stationary grain size distribution obtained from simulation agreed well with the experimental result of pure iron. The Weibull function with a parameter β=2.77 and the Yu-Liu function with a parameter v =2.71 fit the quasi-stationary grain size distribution well. The grain volume distribution is a function that decreased exponentially with increasing grain volume. The distribution of boundary area of grains has a peak at S/〈S〉=0.5, where S is the boundary area of a grain and 〈S〉 is the mean boundary area of all grains in the system. The lognormal function fits the face number distribution well and the peak of the face number distribution is f=10. The mean radius off-faced grains is not proportional to the face number, but appears to be related by a curve convex upward. In the 2D cross-section, both the perimeter law and the Aboav-Weaire law are observed to hold.

关键词： three-dimensional grain growth Monte Carlo simulation grain size distribution topology

Variational Bayesian Kalman filter using natural gradient

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Chinese Journal of Aeronautics 2022年第5期35卷 1-10页

作者： Yumei hu Xuezhi WANG quan PAN Zhentao hu Bill MORAN School of Automation Northwestern Polytechnical UniversityXi’an 710072China The Key Laboratory of Information Fusion Technology Ministry of EducationXi’an 710072China Department of Electrical and Electronic Engineering The University of MelbourneMelbourneVIC 3010Australia School of Engineering RMIT UniversityMelbourneVIC 3000Australia School of Computer and Information Engineering Henan UniversityKaifeng 475001China

We propose a technique based on the natural gradient method for variational lower bound maximization for a variational Bayesian Kalman *** natural gradient approach is applied to the Kullback-Leibler divergence between the parameterized variational distribution and the posterior density of *** a Gaussian assumption for the parametrized variational distribution,we obtain a closed-form iterative procedure for the Kullback-Leibler divergence minimization,producing estimates of the variational hyper-parameters of state estimation and the associated error *** results in both a Doppler radar tracking scenario and a bearing-only tracking scenario are presented,showing that the proposed natural gradient method outperforms existing methods which are based on other linearization techniques in terms of tracking accuracy.

关键词： Kullback-Leibler divergence Natural gradient Nonlinear Kalman filter Target tracking Variational Bayesian optimization