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Hole cleaning evaluation and installation spacing optimization of cuttings bed remover in extended-reach drilling

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Petroleum Science 2024年第3期21卷 2005-2022页

作者： Shuo Peng Wen-jun Huang De-li Gao MOE Key Laboratory of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China

In extended-reach or long-horizontal drilling,cuttings usually deposit at the bottom of the *** cuttings accumulate to a certain thickness,complex problems such as excessive torque and drag,tubing buckling,and pipe stuck probably occur,which results in a lot of non-productive time and remedial *** bed remover can efficiently destroy deposited cuttings in time through hydraulic and mechanical stirring *** paper aims to build a method for hole cleaning evaluation and installation spacing optimization of cuttings bed remover to improve the wellbore cleaning ***,a Computational Fluid Dynamics approach with Eulerian—Eulerian multiphase model was utilized to investigate the mechanism of cuttings transportation,and a new type of cuttings bed remover was ***,an evaluation method of hole cleaning effect of remover was *** that,the effects of several drilling parameters on hole cleaning including flow rate of drilling fluid,rotational speed of drillpipe,rate of penetration,wellbore size,rheological property of drilling fluid,and remover eccentricity on the performance of cuttings bed remover were *** results demonstrate that the new type of remover with streamline blade performs better than conventional *** efficiency of hole cleaning is greatly improved by increasing the rotational speed of drillpipe,flow rate of drilling fluid,remover eccentricity,and 6 rpm Fann dial reading for drilling *** higher rate of penetration and large wellbore size result in worse hole *** findings can serve as an important guide for the structure optimization design of cuttings bed remover and installation spacing of removers.

关键词： Extended-reach drlling Drilling hydraulics Cuttings transport Hole cleaning Cuttings bed remover

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Two-way shape memory effect in a Ti-Zr-Nb-Ta high-temperature shape memory alloy

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Rare Metals 2024年第3期43卷 1257-1262页

作者： Cheng-Yang Xiong Tuo li jun Wang Yan li School of Materials Science and Engineering Beihang UniversityBeijing100191China

The two-way shape memory effect in a Ti-18.5Zr-10Nb-3.5Ta high-temperature shape memory alloy was investigated.X-ray diffraction measurem ent shows that the alloy is composed of orthorhombicα"-martensite.ωphase is not found in Ti-18.5Zr-10Nb-3.5Ta alloy due to the suppressing effect of Ta ***α"-martensite laths are found in the transmission electron microscope observation;after the bending deformation,there appear a lot of *** alloy exhibits a shape memory strain of 3.8%aud a high reverse martensite transformation start temperature of 464 *** maximum two-way shape memory strain of 1.2%is obtained in the alloy with the prebending training strain of 10%.The mechanism can be ascribed to the effect of internal stress field caused by dislocations.

关键词： Ti-Zr Shape memory alloys Two-way shape memory effect

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Time-history performance optimization of flapping wing motion using a deep learning based prediction model

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Chinese Journal of Aeronautics 2024年第5期37卷 317-331页

作者： Tianqi WANG liu liU jun li lifang ZENG School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311800China

Flapping Wing Micro Aerial Vehicles(FWMAVs)have caused great concern in various fields because of their high efficiency and *** wing motion is a very important factor that affects the performance of the aircraft,and previous works have always focused on the time-averaged performance ***,the time-history performance is equally important in the design of motion mechanism and flight control *** this paper,a time-history performance optimization framework based on deep learning and multi-island genetic algorithm is presented,which is designed in order to obtain the optimal two-dimensional flapping wing ***,the training dataset for deep learning neural network is constructed based on a validated computational fluid dynamics *** aerodynamic surrogate model for flapping wing is obtained after the convergence of *** surrogate model is tested and proved to be able to accurately and quickly predict the time-history curves of lift,thrust and ***,the optimization framework is used to optimize the flapping wing motion in two specific cases,in which the optimized propulsive efficiencies have been improved by over 40%compared with the ***,a dimensionless parameter C_(variation)is proposed to describe the variation of the time-history characteristics,and it is found that C_(variation)of lift varies significantly even under close time-averaged *** the importance of time-history performance in practical applications,the optimization that integrates the propulsion efficiency as well as C_(variation)is carried *** final optimal flapping wing motion balances good time-averaged and time-history performance.

关键词： FWMAV Flapping wing motion Deep learning Unsteady aerodynamic performance Optimization Time-history curve

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Celastrus orbiculatus Extract Inhibits Immune Inflammatory Thrombotic State of B-Lymphoma

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Chinese Journal of Integrative Medicine 2024年第11期30卷 1018-1026页

作者： ZHU Miao SHI qing-qing NI jun WU Wei SUN Xing SUN Mei XU Kai-lin liU Yan-qing GU Jian GU Hao Department of Hematology Clinical Medical Col ege Yangzhou University Yangzhou Institute of Hematology Department of Hematology The Affiliated Hospital of Xuzhou Medical University Department of Oncology The Affiliated Hospital of Yangzhou University Yangzhou University Department of Neurology The Affiliated Brain Hospital of Nanjing Medical University

Objective:To investigate the inhibitory effect of Celastrus orbiculatus extracts（COE） on the proliferation of lymphoma cells and the immune regulation ability on inflammation and thrombophilia in ***:The 38B9 lymphoma cells were treated with COE（160μg/mL） and CTX（25 μmol/L）.The apoptosis rate and cell cycle of each group were detected by flow *** secretion of inflammatory factors,including interleukin（IL）-6,IL-10,and tumor necrosis factor α（TNF-α）,in cell supernatant was detected by enzyme-linked immunosorbent assay（EliSA）.In vivo,BALB/c mice were subcutaneously injected with 38B9 lymphoma cells to establish lymphoma ***(3 mg·kg-1·d-1) and CTX(40 mg-kg-1·d-1) were administered to the model mice,*** expression of plasma inflammatory factors（IL-6,IL-10 and TNF-α） and thrombus indexes,including D-dimer（D-D）,von Willebrand factor（vWF） and tissue factor（TF）,were detected by EliSA before tumor bearing（1 d）,after tumor formation（14 d） and after intervention（21 d）.PicoGreen dsDNA was used to detect the level of serum neutrophil extracellular traps（NETs）.Flow cytometry was used to detect the expression of platelet activation marker calcium-dependent lectin-like receptor 2（CLEC-2）.The tumor growth and survival of mice were ***:The 38B9 lymphoma cells were apoptotic after the intervention of COE and *** ratio of G2-M phase cells decreased in COE intervented cells compared with the control cells（P<0.05）,and S phase cells decreased in CTX intervented cells（P<0.05）.Also,the secretion level of IL-6 was significantly reduced after COE or CTX intervention（P<0.05）,and IL-10 was significantly increased（P<0.05）.Furthermore,the tumor mass was reduced,and the median survival time was longer in COE and CTX intervented tumor-bearing mice than in nonintervented *** significantly lower levels of TNF-α,IL-6,NETs,TF,DD and CLEC-2,as well as higher IL-10 were observed in COE and CTX treatment mice in comparision with the control mice（P

关键词： Celastrus orbiculatus extract immune regulation lymphoma murine lymphoma cells proliferation inhibition thrombotic state tumor inflammation

Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

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Tungsten 2024年第3期6卷 585-595页

作者： Hai-Qi Zhang Xiao-jun Zeng qing-qing Zhang Zu-liang Zhang Chu-Long Jin Rong-Hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

Nonlinear Filtering With Sample-Based Approximation Under Constrained Communication:Progress, Insights and Trends

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1539-1556页

作者： Weihao Song Zidong Wang Zhongkui li Jianan Wang qing-Long Han IEEE the State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of Engineering Peking University the Department of Computer Science Brunel University London the School of Aerospace Engineering Beijing Institute of Technology the School of Science Computing and Engineering Technologies Swinburne University of Technology

The nonlinear filtering problem has enduringly been an active research topic in both academia and industry due to its ever-growing theoretical importance and practical *** main objective of nonlinear filtering is to infer the states of a nonlinear dynamical system of interest based on the available noisy measurements. In recent years, the advance of network communication technology has not only popularized the networked systems with apparent advantages in terms of installation,cost and maintenance, but also brought about a series of challenges to the design of nonlinear filtering algorithms, among which the communication constraint has been recognized as a dominating concern. In this context, a great number of investigations have been launched towards the networked nonlinear filtering problem with communication constraints, and many samplebased nonlinear filters have been developed to deal with the highly nonlinear and/or non-Gaussian scenarios. The aim of this paper is to provide a timely survey about the recent advances on the sample-based networked nonlinear filtering problem from the perspective of communication constraints. More specifically, we first review three important families of sample-based filtering methods known as the unscented Kalman filter, particle filter,and maximum correntropy filter. Then, the latest developments are surveyed with stress on the topics regarding incomplete/imperfect information, limited resources and cyber ***, several challenges and open problems are highlighted to shed some lights on the possible trends of future research in this realm.

关键词： Communication constraints maximum correntropy filter networked nonlinear filtering particle filter sample-based approximation unscented Kalman filter

Influence of friction-lubrication characteristics varying with rolling speed on instability of chatter and slip in cold tandem rolling process

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Journal of Iron and Steel Research International 2024年第4期31卷 894-908页

作者： Yan-li Xin Zhi-ying Gao Bo Tian qing-dong Zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China

In the high-speed cold tandem rolling process of thin plate,chatter or slip instability gives rise to the deterioration of equipment and product *** instability behavior is closely related to interfacial friction-lubrication con-dition which is generally characterized by the friction ***,with higher and higher speed requirements,the commonly used model of friction coefficient is no longer applicable and accurate.A novel approach is suggested to calculate the speed-dependent friction coefficient,in which the viscosity-pressure-temperature effects of the lubricant,surface roughness states of work rolls and rolled piece are comprehensively involved and the mixed flm lubrication theory is ***,the influences of friction coefficient on the instability of slip and chatter are investigated for a five-stand cold tandem rolling *** one side,the critical friction coefficient for each stand is determined by calculating the corresponding slip factor;on the other hand,the friction coefficient varying with rolling speed is combined with the model of theoretical critical rolling speed presented under constant friction coefficient,so that the speed threshold is ***,the stable and unstable regions corresponding to the rear three stands are individually discussed,and the technical strategies are proposed to suppress both slip and chatter frequently occurring in the actual rolling process.

关键词： Cold tandem rolling:Oil film thickness Speed-dependent friction coefficient-Slip:Chatter

Disease and Economic Burden of Kashin-Beck Disease—China,2021

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China CDC weekly 2024年第2期6卷 40-44页

作者： Silu Cui Wenjun Que Zhe Jiao qing Deng Xufeng Zhang Yanhong Cao Ning liu Ailin li Alphonse Sowanou Zhe li Tuo Wang Yang li jun Yu junrui Pei NHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University) Key Laboratory of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceInstitute of Kashin-Beck Disease ControlCenter for Endemic Disease ControlChinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina NHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University) Heilongjiang Provincial Key Laboratory of Trace Elements and Human HealthKey Laboratory of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceInstitute of Endemic Fluorosis ControlCenter for Endemic Disease ControlChinese Center for Disease Control and PreventionHarbin Medical UniversityHarbin CityHeilongjiang ProvinceChina

What is already known about this topic?Kashin-Beck disease(KBD)is a chronic and degenerative osteoarthropathy characterized by cartilage *** is an endemic disease that is highly prevalent among the Chinese population and poses a significant health *** is added by this report?This is the first national report on the economic burden of KBD in *** to the data from 2021,KBD has caused significant disease and economic *** most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older,resulting in a total indirect economic burden of 112.74 million Chinese Yuan(CNY).What are the implications for public health practice?The results of this study will contribute to informing the development of tailored prevention and control strategies by the *** strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies,which will be based on the demographic characteristics of the endemic areas.

关键词： prevention degeneration burden

Adaptive coupled-sliding-variable-based finite-time control of composite formation for multi-robot systems

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Science China(Information Sciences) 2024年第10期67卷 244-260页

作者： Xinru MA Hengyu li jun liU Yueying WANG Shaorong XIE jun LUO School of Mechatronic Engineering and Automation Shanghai University School of Mathematics and Computer Application Technology Jining University School of Computer Science Shanghai University College of Mechanical and Vehicle Engineering Chongqing University

This paper focuses on the finite-time control(FTC) of the composite formation consensus(CFC)problems for multi-robot systems(MRSs). The CFC problems are firstly proposed for MRSs under the complex network topology of cooperative or cooperative-competitive networks. Regarding the problems of FTC and CFC on multiple Lagrange systems(MLSs), coupled sliding variables are introduced to deal with the robustness and consistent convergence. Then, the adaptive finite-time protocols are given based on the displacement approaches. With the premised FTC, tender-tracking methods are further developed for the problems of tracking information disparity. Stability analyses of those MLSs mentioned above are clarified with Lyapunov candidates considering the coupled sliding vectors, which provide new verification for tender-tracking systems. Under the given coupled-sliding-variable-based finite-time protocols, MLSs distributively adjust the local formation error to achieve global CFC and perform uniform convergence in time-varying tracking. Finally, simulation experiments are conducted while providing practical solutions for the theoretical results.

关键词： composite formation time-vary tracking information disparity tender-tracking finite-time control nonlinear robots complex networks symmetry consensus