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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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论社会主义核心价值观的形成、内涵与意义

北京师范大学学报（社会科学版） 2015年第3期 5-13页

作者：李文阁 <求是>杂志社北京100727

社会主义核心价值观的形成过程分为酝酿、提出、深化三个阶段。把握社会主义核心价值观的基本内涵,关键是要从价值理念的层次或高度上来理解它,而不是从目标、特征、实现方式、实践要求等角度去理解。培育核心价值观是建立文化自信,化... 详细信息

社会主义核心价值观的形成过程分为酝酿、提出、深化三个阶段。把握社会主义核心价值观的基本内涵,关键是要从价值理念的层次或高度上来理解它,而不是从目标、特征、实现方式、实践要求等角度去理解。培育核心价值观是建立文化自信,化解社会矛盾、解决社会问题、凝聚社会力量的需要。对围绕核心价值观产生的一些困惑和片面理解,对如何深化核心价值观研究,要给出符合时代精神的回答。

关键词：社会主义核心价值观文明自由文化自信

gear walk instability caused by brake-disc friction characteristics

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Chinese Journal of Aeronautics 2024年第2期37卷 343-359页

作者： Xiaoqiong DU Bin li wen CAI linyin LUO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Department of Mechanical Engineering University of MichiganAnn Arbor 48109USA AVIC general Huanan Aircraft Industry Co.Ltd. Zhuhai 519040China

A multi-body dynamic rigid-flexible coupling model of landing gear is established to study the gear walk instability caused by the friction characteristics of the brake *** validating the model with the experimental results,the influence of the landing gear structure and braking system parameters on gear walk is further *** the above factors,the slope of the graph for the friction coefficient of the brake disc and the relative velocity of brake stators and rotors is the most influential factor on gear walk *** trajectory analysis verifies that gear walk occurs when the coupling of multiple factors causes the system to exhibit an equivalent negative damping *** consider a more realistic braking case,a back propagation neural network method is employed to describe the nonlinear behavior of the friction coefficient of the brake *** the realistic nonlinear model of the friction coefficient,the maximum error in predicting the braking torque is less than 10%and the effect of the brake disc temperature on gear walk is *** results reveal that a more negative friction slope may contribute to a more severe unstable gear walk,and reducing the braking pressure is an effective approach to avoid gear walk,which provides help for future braking system design.

关键词： gear walk Friction characteristics of brake disc Brake-induced vibration Negative damping Rigid-flexible coupling Negative slope of braking torque

Distributed user pairing and effective computation offloading in aerial edge networks

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Chinese Journal of Aeronautics 2024年第4期37卷 378-390页

作者： Wei liANG Shuhui wen lixin li Jingjing CUI School of Electronics and Information Northwestern Polytechnical UniversityXi’an CN710072China The State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an CN710126China School of Electronics and Computer Science University of SouthamptonSouthampton SO167NSUK

Future Sixth-generation (6G) mobile communication networks extremely require the global connectivity and the ground Base Stations (BSs) are difficult to develop in some specific areas,such as mountainous ***,the aerial networks are the key framework for the future communications,in which the aerial vehicle could act as the access ***,Mobile Edge Computing (MEC) is also essential to enhance the data processing capabilities of aerial *** this paper,we study a comprehensive communication-computation resource management problem for jointly optimizing user pairing,power and time allocation in the MEC aided Cognitive Radio (CR) aerial networks,namely CR-MEC aerial ***,this multilevel optimization problem could be decomposed into the user pairing and power allocation as well as time allocation *** the conceived CR-MEC aerial networks,we propose a User Pairing and Computation Offloading Management Algorithm (UPCOMA) based on three-sided matching theory,aiming to minimize the system’s energy *** the first step of UPCOMA,multiple Primary Users (PUs) and Cognitive Users (CUs) on the ground negotiate to each other with the suitable power allocation coefficients and construct the stable user ***,the stable user pairs would match to a high altitude platform who act as the base station,which is for appropriately allocating Transmission Time Slots (TSs) at the second step of ***,a hybrid offloading mode is proposed in our conceived networks in order to support ground users to offload their tasks adaptively according to their individual ***,the simulation results reveal that the relative performance of UPCOMA is close to that of the Brute-Force Search Algorithm (BFSA) with low ***,the hybrid offloading mode with less energy consumption supports much more ground user pairs to offload tasks compared to the binary mode.

关键词： Aerial edge computing Binary offloading Cognitive radio Hybrid offloading Resource management

A new integrated model of deformation resistance and its application in prediction of rolling force of a thick plate

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Journal of Iron and Steel Research International 2024年第4期31卷 882-893页

作者： Shun-hu Zhang Yan li li-zhi Che wen-hao Tian Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The prediction accuracy of existing models of the rolling force of a thick plate is always very *** address this problem,a high-precision genetic algorithm-backpropagation network(GA-BP)model of deformation resistance was built,and its integration with the traditional fitted model was further ***,a novel rolling force model was obtained by embedding the integration model of deformation resistance in the original model of rolling *** to this research idea,the industrial data are normalized at *** this basis,the interactions among the process parameters were disclosed through the variance analysis,and then described by various virtual *** factors are set as part of input ***,the optimal structure of the GA-BP model of deformation resistance was determined and an integration model of deformation resistance was ***,a novel rolling force model is obtained by substituting the traditional fitted deformation resistance into the Sims model with the integration model of the deformation *** results proves that the introduction of virtual factors can increase the hit rate of±5%from 75.8%to 78%and can reduce the root mean square error from 4.72%to 4.48%.Besides,it is found that the mean relative error of the traditional fitted deformation resistance is 0.142,while that of the modified deformation resistance is only *** addition,the mean relative error in the original rolling force model is 0.145,while that of the present model is only 0.03.

关键词： Integration model-Deformation resistance Variance analysis Virtual factor genetic algorithm-backpropagation network model

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回归现实生活世界——现代哲学的基本趋向

教学与研究 2000年第1期 44-51页

作者：李文阁中国社会科学院哲学研究所北京100732

从马克思开始的现代哲学旨在回归近代哲学由之出发但却遗忘了的现实生活世界。阐述由科学世界向生活世界回归的发生、实质和意义,廓清马克思的生活世界观的内容,并由此考察传统哲学的三大领域:自然、历史和认识,才能真正体认现代哲学所... 详细信息

从马克思开始的现代哲学旨在回归近代哲学由之出发但却遗忘了的现实生活世界。阐述由科学世界向生活世界回归的发生、实质和意义,廓清马克思的生活世界观的内容,并由此考察传统哲学的三大领域:自然、历史和认识,才能真正体认现代哲学所实现的哲学视野的根本置换。在新的世纪。

关键词：现代哲学马克思哲学生活世界实践论思维方式

工读学生与普通学生攻击性行为外显和内隐社会认知特点的比较研究

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福建师范大学学报（哲学社会科学版） 2005年第2期 141-145,147页

作者：李闻戈福建师范大学教育科学与技术学院福建福州350007

本研究借助内隐社会认知的研究范式 ,从内隐和外显两个层面对工读学生和普通学生攻击性行为社会认知特点进行比较研究。结果表明 :(1 )与普通学生相比 ,工读生在攻击性行为外显社会认知特征上 ,缺乏对弱者的普遍同情心 ,未牢固地建立对... 详细信息

本研究借助内隐社会认知的研究范式 ,从内隐和外显两个层面对工读学生和普通学生攻击性行为社会认知特点进行比较研究。结果表明 :(1 )与普通学生相比 ,工读生在攻击性行为外显社会认知特征上 ,缺乏对弱者的普遍同情心 ,未牢固地建立对攻击性行为作否定评价的社会道德规范意识 ;(2 )在攻击性行为内隐社会认知特征上 ,两类学生都表现出偏好攻击者 ,而工读生的偏好的程度更强烈 ;(3 )普通学生对中立人物的偏好率明显高于攻击者和被攻击者的总和 ,但工读生仍然更偏好于攻击者。

关键词：工读学生攻击性行为社会认知特点

Fortifying Smart Grids: A Holistic Assessment Strategy against Cyber Attacks and Physical Threats for Intelligent Electronic Devices

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Computers, Materials & Continua 2024年第8期80卷 2579-2609页

作者： Yangrong Chen June li Yu Xia Ruiwen Zhang lingling li Xiaoyu li lin ge School of Computer Science Zhengzhou University of AeronauticsZhengzhou450046China Henan Xin’an Century Technology Co. Ltd.Henan Data Security Engineering Technology Research CenterZhengzhou450046China Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of EducationSchool of Cyber Science and EngineeringWuhan UniversityWuhan430072China

Intelligent electronic devices(IEDs)are interconnected via communication networks and play pivotal roles in transmitting grid-related operational data and executing control *** the context of the heightened security challenges within smart grids,IEDs pose significant risks due to inherent hardware and software vulner-abilities,as well as the openness and vulnerability of communication *** grid security,distinct from traditional internet security,mainly relies on monitoring network security events at the platform layer,lacking an effective assessment mechanism for ***,we incorporate considerations for both cyber-attacks and physical faults,presenting security assessment indicators and methods specifically tailored for ***,we outline the security monitoring technology for IEDs,considering the necessary data sources for their security ***,we classify IEDs and establish a comprehensive security monitoring index system,incorporating factors such as running states,network traffic,and abnormal *** index system contains 18 indicators in 3 ***,we elucidate quantitative methods for various indicators and propose a hybrid security assessment method known as GRCW-hybrid,combining grey relational analysis(GRA),analytic hierarchy process(AHP),and entropy weight method(EWM).According to the proposed assessment method,the security risk level of IEDs can be graded into 6 levels,namely 0,1,2,3,4,and *** higher the level,the greater the security ***,we assess and simulate 15 scenarios in 3 categories,which are based on monitoring indicators and real-world situations encountered by *** results show that calculated security risk level based on the proposed assessment method are consistent with actual ***,the reasonableness and effectiveness of the proposed index system and assessment method are validated.

关键词： Smart grid intelligent electronic device security assessment abnormal behaviors network traffic running states

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激光表面改性的发展趋势

金属热处理 2006年第11期31卷 1-7页

作者：张光钧李军李文戈上海工程技术大学激光工业技术研究所上海201620 上海工程技术大学材料工程学院上海201620

从激光表面改性的技术特点及先进制造业的发展需求出发,论述了激光表面改性在纳米表面工程、绿色再制造、复合表面工程、智能制造及柔性加工等领域的发展趋势。

关键词：激光表面改性纳米表面工程再制造复合处理智能制造柔性制造准分子激光