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Adaptive Integral-type Sliding Mode Control for Spacecraft Attitude Maneuvering Under Actuator Stuck Failures 被引量:17
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作者 HU Qinglei ZHANG Youmin +1 位作者 HUO Xing XIAO Bing 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第1期32-45,共14页
A fault tolerant control (FTC) design technique against actuator stuck faults is investigated using integral-type sliding mode control (ISMC) with application to spacecraft attitude maneuvering control system. The... A fault tolerant control (FTC) design technique against actuator stuck faults is investigated using integral-type sliding mode control (ISMC) with application to spacecraft attitude maneuvering control system. The principle of the proposed FTC scheme is to design an integral-type sliding mode attitude controller using on-line parameter adaptive updating law to compensate for the effects of stuck actuators. This adaptive law also provides both the estimates of the system parameters and external disturbances such that a prior knowledge of the spacecraft inertia or boundedness of disturbances is not required. Moreover, by including the integral feedback term, the designed controller can not only tolerate actuator stuck faults, but also compensate the disturbances with constant components. For the synthesis of controller, the fault time, patterns and values are unknown in advance, as motivated from a practical spacecraft control application. Complete stability and performance analysis are presented and illustrative simulation results of application to a spacecraft show that high precise attitude control with zero steady-error is successfully achieved using various scenarios of stuck failures in actuators. 展开更多
关键词 integral sliding mode control attitude maneuvering stuck failure adaptive control SPACECRAFT
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Trajectory Tracking Strategy for Gliding Hypersonic Vehicle with Aileron Stuck at an Unknown Angle 被引量:2
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作者 Haibo Ji Lei Wang 《Journal of Beijing Institute of Technology》 EI CAS 2019年第3期447-455,共9页
A nonlinear robust trajectory tracking strategy for a gliding hypersonic vehicle with an aileron stuck at an unknown position is presented in this paper. First, the components of translational motion dynamics perpendi... A nonlinear robust trajectory tracking strategy for a gliding hypersonic vehicle with an aileron stuck at an unknown position is presented in this paper. First, the components of translational motion dynamics perpendicular to the velocity are derived, and then a guidance law based on a time-varying sliding mode method is used to realize trajectory tracking. Furthermore, the rotational equations of motion are separated into an actuated subsystem and an unactuated subsystem. And an adaptive time-varying sliding mode attitude controller is proposed based on the actuated subsystem to track the command attitude and the tracking performance and robustness are therefore enhanced. The proposed guidance law and attitude controller make the hypersonic vehicle fly along the reference trajectory even when the aileron is stuck at an unknown angle. Finally, a hypersonic benchmark platform is used to demonstrate the effectiveness of the proposed strategy. 展开更多
关键词 TRAJECTORY tracking stuck AILERON TIME-VARYING SLIDING mode
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A numerical method for determining the stuck point in extended reach drilling 被引量:2
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作者 Sun Lianzhong Gao Deli 《Petroleum Science》 SCIE CAS CSCD 2011年第3期345-352,共8页
A stuck drill string results in a major non-productive cost in extended reach drilling engineering. The first step is to determine the depth at which the sticking has occurred. Methods of measurement have been proved ... A stuck drill string results in a major non-productive cost in extended reach drilling engineering. The first step is to determine the depth at which the sticking has occurred. Methods of measurement have been proved useful for determining the stuck points, but these operations take considerable time. As a result of the limitation with the current operational practices, calculation methods are still preferred to estimate the stuck point depth. Current analytical methods do not consider friction and are only valid for vertical rather than extended reach wells. The numerical method is established to take full account of down hole friction, tool joint, upset end of drill pipe, combination drill strings and tubular materials so that it is valid to determine the stuck point in extended reach wells. The pull test, torsion test and combined test of rotation and pulling can be used to determine the stuck point. The results show that down hole friction, tool joint, upset end of drill pipe, tubular sizes and materials have significant effects on the pull length and/or the twist angle of the stuck drill string. 展开更多
关键词 Extended reach drilling stuck pipe torque and drag numerical method
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Mobile Deals Set to Lure Shoppers Stuck in Line
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《China's Foreign Trade》 2011年第23期76-76,共1页
According to New York Times on November 19, as retailers battle to draw customers into their stores on Black Friday, online merchants are plotting a cunning ambush, offering an arsenal of mobile-only deals intended to... According to New York Times on November 19, as retailers battle to draw customers into their stores on Black Friday, online merchants are plotting a cunning ambush, offering an arsenal of mobile-only deals intended to pick off shoppers as they wait in line. The Gilt Groupe, for example, which 展开更多
关键词 Mobile Deals Set to Lure Shoppers stuck in Line LINE
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基于红外热成像技术观察滞针提拉法治疗亚急性期周围性面瘫的临床疗效
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作者 徐晓霜 李肖伟 +5 位作者 舒玉铃 张雅婷 张京璨 苗婷婷 杨骏 石海平 《中国针灸》 北大核心 2026年第1期49-53,共5页
目的:基于红外热成像技术观察滞针提拉法治疗亚急性期周围性面瘫的临床疗效。方法:将60例亚急性期周围性面瘫患者随机分为观察组和对照组,各30例。对照组采用常规针刺治疗,穴取患侧牵正、四白、阳白、鱼腰、颊车、地仓等;观察组在对照... 目的:基于红外热成像技术观察滞针提拉法治疗亚急性期周围性面瘫的临床疗效。方法:将60例亚急性期周围性面瘫患者随机分为观察组和对照组,各30例。对照组采用常规针刺治疗,穴取患侧牵正、四白、阳白、鱼腰、颊车、地仓等;观察组在对照组的基础上,选取阳白透刺鱼腰、四白透刺地仓、地仓透刺颊车三组穴位施用滞针提拉法。两组患者均每次留针30 min,隔日治疗1次,至病程的第28天结束。采用红外热像仪观察两组患者治疗前后阳白、四白和地仓健侧与患侧温度差值(ΔT),比较两组患者治疗前后House-Brackmann(H-B)分级、Sunnybrook面神经评定量表评分,对两组患者痊愈时间进行生存分析,并评定临床疗效。结果:治疗后,两组患者阳白、四白、地仓穴位ΔT均较治疗前降低(P<0.05),且观察组低于对照组(P<0.05)。两组患者H-B分级、Sunnybrook面神经评定量表评分均较治疗前改善(P<0.05),且观察组优于对照组(P<0.05)。观察组中位痊愈时间短于对照组(P<0.05)。观察组总有效率为96.7%(29/30),高于对照组的90.0%(27/30,P<0.05)。结论:在常规针刺的基础上,滞针提拉法可提升亚急性期周围性面瘫的临床疗效,可有效改善临床症状,缩短病程。 展开更多
关键词 周围性面瘫 针刺 滞针提拉法 红外热成像
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热-粒耦合作用下插装式换向阀阀芯滞卡与磨损特性研究
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作者 薛静 冀宏 +2 位作者 柴文伟 罗畅敏 陈乾鹏 《机床与液压》 北大核心 2026年第2期177-182,194,共7页
为探究插装式换向阀阀芯在颗粒污染、温度以及热-粒耦合作用下的滞卡力特性、表面磨损规律及其对换向速度的影响,利用自主设计的滞卡力测试装置,在不同污染等级的油液、不同温度条件以及热-粒耦合条件下,对阀芯的滞卡力进行测量;采用三... 为探究插装式换向阀阀芯在颗粒污染、温度以及热-粒耦合作用下的滞卡力特性、表面磨损规律及其对换向速度的影响,利用自主设计的滞卡力测试装置,在不同污染等级的油液、不同温度条件以及热-粒耦合条件下,对阀芯的滞卡力进行测量;采用三维变焦表面形貌仪测量磨损前后阀芯表面微观形貌参数;最后,分析颗粒作用和热-粒耦合作用下阀芯滞卡对换向阀换向速度的影响。结果表明:在颗粒单作用下阀芯的滞卡力较小,多数时间处于1 N左右;在温度单因素下阀芯的滞卡力明显增大,峰值达到7.24 N,且阀芯温度、热形变与滞卡力呈正相关;在热-粒耦合作用下,阀芯滞卡力峰值明显增大,达到13.82 N;表明温度升高显著提升了敏感颗粒的数量。磨损后阀芯表面平均粗糙度Ra显著增大,例如配合段2周向的Ra从磨损前的0.94572μm增至2.6673μm;当阀芯温度从90℃升高至110℃时,摩擦力占弹簧预紧力的比值从9.33%增至50.31%,响应滞后率从5.02%增至41.87%,使摩擦力接近于驱动力进而导致阀芯卡死,严重影响转换活门的换向速度。研究为降幅阀芯滞卡以及优化阀芯结构提供了理论依据。 展开更多
关键词 滑阀滞卡 热-粒耦合 敏感颗粒 表面形貌 换向速度
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Therapeutic Observation on “Green Tortoise Probing Cave”Operation plus Stuck Needle Method in Treating Transverse Process Syndrome of the Third Lumbar Vertebra 被引量:2
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作者 梁业安 王玲玲 张沈煜 《Journal of Acupuncture and Tuina Science》 2009年第5期286-287,共2页
Transverse process syndrome of the third lumbar vertebra is a common cause of lumbago and sciatica It is manifested by localized soreness, distention and pain on unilateral or bilateral aspect of the third lumbar tran... Transverse process syndrome of the third lumbar vertebra is a common cause of lumbago and sciatica It is manifested by localized soreness, distention and pain on unilateral or bilateral aspect of the third lumbar transverse process. There is also fixed tenderness point at the tip of the transverse process. This condition frequently occurs in young adults who are engaged in physical work. In recent years, the author used green tortoise probing cave method and stuck needle method for treating 72 cases of transverse process syndrome of the third lumbar vertebra, it is now report as follows. 展开更多
关键词 Acupuncture Therapy Low Back Pain stuck Needle
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卡钻风险无监督诊断与处置措施检索推荐系统
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作者 吕泽昊 李桢 +3 位作者 魏风奇 纪国栋 李令东 陈伟峰 《新疆石油天然气》 2026年第1期26-32,共7页
卡钻是钻井过程中常见的风险,严重制约安全高效钻井。传统的阻卡诊断与卡钻处置方法大多基于专家经验、机理模型或监督机器学习算法,存在诊断滞后、过拟合虚警高、主观性强和适配性低等问题。基于无监督学习与K近邻算法,提出了卡钻风险... 卡钻是钻井过程中常见的风险,严重制约安全高效钻井。传统的阻卡诊断与卡钻处置方法大多基于专家经验、机理模型或监督机器学习算法,存在诊断滞后、过拟合虚警高、主观性强和适配性低等问题。基于无监督学习与K近邻算法,提出了卡钻风险诊断与处置案例推荐方法,并形成软件系统。该系统分为卡钻风险诊断与卡钻事故处理两大核心模块。卡钻风险诊断模块采用孤立森林算法(Isolation Forest)对井下实时数据中的核心工程参数的异常变化趋势进行监控与诊断;卡钻事故处理模块则采用基于KD-Tree+KNN的案例推理算法检索卡钻案例决策库,将相似度最高的前三个案例数据返回到客户端辅助工程师处理卡钻事故。基于上述研究,设计并实现了基于案例推理的井下卡钻智能诊断系统。测试表明,本系统在事故前5 min左右成功发出预警,并快速检索出相似度最高的3个历史处置案例,并推送到界面,为工程师提供了直接的决策支持。 展开更多
关键词 卡钻预测 案例推理 孤立森林 KD树
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A New Classification of Path-Delay Fault Testability in Terms of Stuck-at Faults
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作者 SubhashisMajumder BhargabB.Bhattacharya +1 位作者 VishwaniD.Agrawal MichaelL.Bushnell 《Journal of Computer Science & Technology》 SCIE EI CSCD 2004年第6期955-964,共10页
A new classification of path-delay fault testability in a combinational circuit is presented in terms of testability of stuck-at faults in an equivalent circuit. Earlier results describing correlation of path-delay an... A new classification of path-delay fault testability in a combinational circuit is presented in terms of testability of stuck-at faults in an equivalent circuit. Earlier results describing correlation of path-delay and stuck-at faults are either incomplete, or use a complex model of equivalent circuit based on timing parameters. It is shown here that a path-delay fault (rising or falling) is testable if and only if certain single or multiple stuck-at fault in the equivalent circuit is testable. Thus, all aspects of path-delay faults related to testability under various classification schemes can be interpreted using the stuck-at fault model alone. The results unify most of the existing concepts and provide a better understanding of path-delay faults in logic circuits. Keywords delay fault - false path - redundancy - stuck-at fault Regular PaperThis work was funded in part by Motorola India Electronics Ltd., Bangalore 560042, India.An earlier version of this paper appeared in the Proceedings of the 12th Int. Coaf. VLSI Design, Jan. 1999.Subhashis Majumder is a professor and course leader for the Computer Science and Engineering Department of International Institute of Information Technology, Kolkata. He started his career in Texas Instruments India Pvt. Ltd. and has over seven years of industry experience. He received his M. Tech degree in computer science from the Indian Statistical Institute, Kolkata in 1996. His undergraduate work was done in the Electronics and Telecommunication Engineering Dept. of the Jadvpur University, Koikata. He also worked as a research assistant in the Computer Eng. Dept. of Rutgers University for a year. He has led product development teams working on protocol stack development as well as VoIP. His current areas of interest include delay fault testing, wire routing, partitioning, approximation algorithms, and application of computational geometry to CAD problems.Bhargab B. Bhattacharya received the B.Sc. degree in physics from the Presidency College, Calcutta, the B.Tech. and M.Tech. degrees in radiophysics and electronics, and the Ph.D. degree in computer science all from the University of Calcutta, India. Since 1982, he has been on the faculty of the Indian Statistical Institute, Calcutta, where currently he is a full professor. He visited the Department of Computer Science and Engineering, University of Nebraska-Lincoln, USA, during 1985–1987, and 2001–2002, and the Fault-Tolerant Computing Group, Institute of Informatics, at the University of Potsdam, Germany during 1998–2000. His research interest includes logic synthesis and testing of VLSI circuits, physical design, graph algorithms, and image processing architecture. He has published more than 130 papers in archival journals and refereed conference proceedings, and holds 6 United States patents. Currently, he is collaborating with Intel Corporation, USA, and IRISA, France, for development of image processing hardware and reconfigurable parallel computing tools. Dr. Bhattacharya is a fellow of the Indian National Academy of Engineering. He served on the conference committees of the International Test Conference (ITC), the Asian Test Symposium (ATS), the VLSI Design and Test Workshop (VDAT), the International Conference on Advanced Computing (ADCOMP), and the International Conference on High-Performance Computing (HiPC). For the International Conference on VLSI Design, he served as Tutorial Co-Chair (1994), Program Co-Chair (1997), General Co-Chair (2000), and as a member of the Steering Committee during 2001–2003. He is on the editorial board of the Journal of Circuits, Systems, and Computers (World Scientific, Singapore), and the Journal of Electronic Testing: Theory and Applications (Kluwer Academic Publishers, USA). [http://www.isical.ac.in/~bhargab]Vishwani D. Agrawal is the James J. Danaher Professor of Electrical and Computer Engineering at Auburn University, Alabama. He has over thirty years of industry and University experience, working at Bell Labs, Murray Hill, NJ; Rutgers University, New Brunswick, NJ; TRW, Redondo Beach, CA; IIT, Delhi, India; EG&G, Albuquerque. NM; and ATI, Champaign, IL. His areas of work include VLSI testing, lowpower design, and microwave antennas. He obtained his B.E. degree from the University of Roorkee (renamed as Indian Institute of Technology, Roorkee), India, in 1964; M.E. degree from the Indian Institute of Science, Bangalore, India, in 1966; and Ph.D. degree in electrical engineering from the University of Illinois, Urbana-Champaign, in 1971. He has published over 250 papers, has coauthored five books and holds thirteen United States patents. His textbook, Essentials of Electronic Testing for Digital, Memory and Mixed-Signal VLSI Circuits (Kluwer Academic Publishers), co-authored with M. L. Bushnell, was published in 2000. He is the founder and Editor-in-Chief (1990-) of the Journal of Electronic Testing: Theory and Applications, and a past Editor-in-Chief (1985–87) of the IEEE Design & Test of Computers magazine. He is the Founder and Consulting Editor of the Frontiers in Electronic Testing Book Series of Kluwer Academic Publishers, Boston. He is a co-founder of the International Conference on VLSI Design, and the International Workshops on VLSI Design and Test, held annually in India. He has served on numerous conference committees and is a frequently invited speaker. He was the invited Plenary Speaker at the 1998 International Test Conference, Washington D.C., and the Keynote Speaker at the Ninth Asian Test Symposium in December 2000. During 1989 and 1990, he served on the Board of Governors of the IEEE Computer Society, and in 1994, chaired the Fellow Selection Committee of that Society. He has received seven Best Paper Awards and one Honorable Mention Paper Award. In 1998, he received the Harry H. Goode Memorial Award of the IEEE Computer Society, for innovative contributions to the field of electronic testing, and in 1993, received the Distinguished Alumnus Award of the University of Illinois at Urbana-Champaign, in recognition of his outstanding contributions in design and test of VLSI systems. Dr. Agrawal is a fellow of the IEEE, the ACM, and IETE-India. He has served on the advisory boards of the ECE Departments at University of Illinois, New Jersey Institute of Technology, and the City College of the City University of New York. [http://www.ece.wisc.edu/~va]Michael L. Bushnell is a professor and a Board of Trustees Research Fellow in the Electrical and Computer Engineering Department at Rutgers University, New Jersey. He was also a Henry Rutgers Research Fellow. He has 24 years of industry and university experience, working at General Electric, Honeywell, Instron, Applicon, and Rutgers University. He received his Ph.D. degree in 1986 and his M.S. degree in 1983, both from Carnegie Mellon University. His undergraduate work was done at the Massachusetts Institute of Technology. He is a Presidential Young Investigator (1990) of the National Science Foundation of the United States. He is a co-author of 4 books (including the leading VLSI testing textbook entitled Essentials of Electronic Testing for Digital, Memory and Mixed-Signal VLSI Circuits (Kluwer Academic Publishers, 2000), co-authored with Vishwani Agrawal), 91 papers, and 7 patents. He is the co-author of two Prize Papers and one Honorable Mention paper. He served twice as Program Co-Chair of the International Conference on VLSI Design (1995 and 1996), and twice as the Conference Vice-Chair of the North Atlantic Test Workshop (2002 and 2003). His current VLSI CAD research interests are automatic mixed-signal circuit test-pattern generation, built-in self-testing, synthesis for testability, fault modeling for nano-technology, and low-power design. [http://www.ece.rutgers.edu/directory/bushnell.html] 展开更多
关键词 delay fault false path REDUNDANCY stuck-at fault
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BIST Design for Detecting Multiple Stuck—Open Faults in CMOS Circuits Using Transition Count
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作者 HafizurRahaman DebeshK.Das 《Journal of Computer Science & Technology》 SCIE EI CSCD 2002年第6期731-737,共7页
This paper presents a built-in self-test (BIST) scheme for detecting allrobustly testable multiple stuck-open faults confined to any single complex cell of a CMOS circuit.The test pattern generator (TPG) generates all... This paper presents a built-in self-test (BIST) scheme for detecting allrobustly testable multiple stuck-open faults confined to any single complex cell of a CMOS circuit.The test pattern generator (TPG) generates all n·2~n single-input-change (SIC) ordered test pairsfor an n-input circuit-under-test (CUT) contained in a sequence of length 2n·2~n. The proposeddesign is universal, i.e., independent of the structure and functionality of the CUT. A counter thatcounts the number of alternate transitions at the output of the CUT, is used as a signatureanalyzer (SA). The design of TPG and SA is simple and no special design-or synthesis-for-testabilitytechniques and/or additional control lines are needed. 展开更多
关键词 BIST CMOS complex cell stuck-open faults testing TPG
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断层破碎带双护盾TBM卡刀盘脱困技术
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作者 李旭辉 叶焰中 +1 位作者 贺文浩 崔浩 《广东水利水电》 2026年第2期105-109,115,共6页
面对断层破碎带等不良地质时,双护盾TBM受自身工法限制,常会出现TBM卡刀盘或者卡机的情况,在借鉴行业工程案例经验的基础上,以罗铁工程T3区间双护盾TBM卡刀盘事件为例,对本次断层破碎刀双护盾TBM卡刀盘原因进行了深入分析,制定针对性解... 面对断层破碎带等不良地质时,双护盾TBM受自身工法限制,常会出现TBM卡刀盘或者卡机的情况,在借鉴行业工程案例经验的基础上,以罗铁工程T3区间双护盾TBM卡刀盘事件为例,对本次断层破碎刀双护盾TBM卡刀盘原因进行了深入分析,制定针对性解决方案,并开展复推总结。研究成果可为类似工程提供参考借鉴。 展开更多
关键词 TBM 双护盾TBM 卡刀盘 卡机 脱困 复推
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Fault detection for sector-bounded non-linear systems with servo inputs and sensor stuck faults
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作者 Ying Gu Xiao-Jian Li 《Journal of Control and Decision》 EI 2019年第3期147-165,共19页
This paper addresses the fault detection(FD)problem for discretetime sector-bounded non-linear systems with finite-frequency servo inputs.The non-linear systems are firstly modelled as multi-models.The main contributi... This paper addresses the fault detection(FD)problem for discretetime sector-bounded non-linear systems with finite-frequency servo inputs.The non-linear systems are firstly modelled as multi-models.The main contributions are that a novel FD filter which combines the finite-frequency H∞and H−indices is designed.Different from the existing methods,the proposed FD scheme guarantees that the generated residuals are robust against the servo inputs in fault-free case and sensitive to them in faulty cases.Thus,the small sensor stuck faults including outagefaults can be detected.For this class of systems,the existing finite-frequency FD filter design methods are invalid.A new lemma is developed to characterise the system performances in finite-frequency domain.In addition,sufficient conditions for the existence of such a FD filter are derived by introducing slack variable and linear matrix inequalities techniques.Finally,an example is presented to demonstrate the method and its effectiveness. 展开更多
关键词 Fault detection servo inputs sensor stuck faults sector-bounded nonlinearity finite-frequency domain
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套管封隔器坐封失效原因分析及对策
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作者 伍怡 《石油工业技术监督》 2026年第1期14-18,共5页
近年来完井封隔器在川渝地区油田广泛应用,完井封隔器因长期可靠密封性和耐恶劣环境能力成为主流选择。但完井封隔器在使用过程中,因各种原因导致失效,通常表现为异常坐封,可能导致封隔器卡瓦提前张开或胶筒非正常膨胀,造成管柱遇阻、... 近年来完井封隔器在川渝地区油田广泛应用,完井封隔器因长期可靠密封性和耐恶劣环境能力成为主流选择。但完井封隔器在使用过程中,因各种原因导致失效,通常表现为异常坐封,可能导致封隔器卡瓦提前张开或胶筒非正常膨胀,造成管柱遇阻、无法下入或解封困难;封隔器未完全胀封,导致验封失败等。完井封隔器失效,会造成作业成本与效率损失。如二次作业,需起出管柱重新完井,增加作业时间和费用。针对上述情况,通过对比几种完井封隔器失效情况,采用现场数据、车间数据分析失效原因,在管柱设计、作业条件等方面提出改进措施。为改善作业环境及条件,提高完井封隔器管柱成功率提供思路。 展开更多
关键词 套管封隔器 坐封失效 遇卡 泥浆沉淀 无固相结晶
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伊拉克米桑油田卡尾管事故预防及处理技术
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作者 王宝 《石化技术》 2026年第1期39-41,共3页
本文针对伊拉克米桑油田水平井作业中频发的尾管卡钻事故,以6井6-5/8"尾管卡钻为典型案例,通过事故井地质条件、井眼轨迹特征及作业参数分析,结合同区块2/4/60井的对比案例,揭示了尾管卡钻的主要原因是井眼局部狗腿度过大、扶正器... 本文针对伊拉克米桑油田水平井作业中频发的尾管卡钻事故,以6井6-5/8"尾管卡钻为典型案例,通过事故井地质条件、井眼轨迹特征及作业参数分析,结合同区块2/4/60井的对比案例,揭示了尾管卡钻的主要原因是井眼局部狗腿度过大、扶正器配置不合理及管柱静置时间过长导致的摩阻骤增,并给出了尾管卡钻后的处理措施。最后本文还提出了优化地质卡层预测与轨迹控制策略、采用半刚性扶正器并科学布设、改进尾管下入作业流程等预防措施。现场应用表明,该技术体系可显著降低复杂地质条件下水平井尾管卡钻风险。 展开更多
关键词 伊拉克BUCN油田 水平井 尾管卡钻 井眼轨迹控制 扶正器优化 预防措施
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CRISIS FOCUS: Stuck With Liquidity
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《Beijing Review》 2011年第1期35-35,共1页
With the risk of large-scale and systematic financial market crashes all but diminished, 2011 marks the beginning of the post-crisis era for the global economy and financial markets. But an old friend of 2010-
关键词 CRISIS FOCUS stuck With Liquidity
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Stuck in the Middle
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作者 YIN PUMIN 《Beijing Review》 2011年第36期20-22,共3页
Better-paid urban residents aren’t enjoying the life they have expected Sun Lijun works as a software engineer at a Beijing-based IT company and earns around 8,000 yuan ($1,254) a month. His relatively high income me... Better-paid urban residents aren’t enjoying the life they have expected Sun Lijun works as a software engineer at a Beijing-based IT company and earns around 8,000 yuan ($1,254) a month. His relatively high income means his friends and colleagues, as well as China’s statistical agencies, 展开更多
关键词 stuck in the Middle
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Stuck in the Cold War
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作者 Clifford A.Kiracofe 《Beijing Review》 2016年第44期22-23,共2页
The Obama administration's eight years in office have failed to reset U.S.-Russia relations. Instead. they have moved toward a provocative and volatile new Cold War scenario, thereby increasing world tensions. With P... The Obama administration's eight years in office have failed to reset U.S.-Russia relations. Instead. they have moved toward a provocative and volatile new Cold War scenario, thereby increasing world tensions. With President Barack Obama now a lame duck and the U.S. presidential election imminent. international concern over Washington's future direction is understandable. 展开更多
关键词 stuck in the Cold War
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Scraping technique of stuck needle at Anmian point in the treatment of insomnia: a randomized controlled trial
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作者 张全爱 《China Medical Abstracts(Internal Medicine)》 2013年第3期136-136,共1页
Objective To compare the efficacy difference in the treatment of insomnia between scraping technique of stuck needle and conventional acupuncture at Anmian (Extra) .Methods One hundred and thirty one
关键词 NEEDLE acupuncture stuck hundred thirty PSQI DISTURBANCE apparently ARRIVAL rotating
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Teen Dies After Prized Fish Stuck in Throat
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作者 E.J.Mundell 郭世梅 《当代外语研究》 2003年第9期24-24,共1页
柬埔寨的一个小孩在河里活捉了一条小鱼,不慎,小鱼一个挣扎,从小孩手中滑脱,结果落到小孩嘴中,卡在喉咙,小孩因此不治身亡。Accidents canhappen at any time.是文末的慨叹。文虽短,但有两个语言难点。一是标题中的形容词prized如何理解... 柬埔寨的一个小孩在河里活捉了一条小鱼,不慎,小鱼一个挣扎,从小孩手中滑脱,结果落到小孩嘴中,卡在喉咙,小孩因此不治身亡。Accidents canhappen at any time.是文末的慨叹。文虽短,但有两个语言难点。一是标题中的形容词prized如何理解?prize有“捕获”的意思,如:The ship was prized for vio-lating neutrality./那艘船因违犯中立而被捕获。如此理解也许不对,分析请读文内注释;二是文中出现where it became stuck because of barbs running down itsback.这里的barb有“鱼钩”的意思,但是,根据上下文,大概也不能如此理解,如何理解也请看文内注释。读者若有不同看法,可发email给我们。 展开更多
关键词 Teen Dies After Prized Fish stuck in Throat
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面向脉动阵列加速器的软硬件协同容错设计
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作者 魏晓辉 关泽宇 +2 位作者 王晨洋 岳恒山 吴旗 《计算机科学》 北大核心 2025年第5期91-100,共10页
近年来,随着模型推理精度的不断提高,卷积神经网络(CNN)在安全关键领域得到了广泛应用。为了满足CNN在实时性、高性能和低功耗计算方面的需求,领域专用架构的CNN加速器应运而生。其中,脉动阵列架构凭借其结构简单和高并行度等优势被广... 近年来,随着模型推理精度的不断提高,卷积神经网络(CNN)在安全关键领域得到了广泛应用。为了满足CNN在实时性、高性能和低功耗计算方面的需求,领域专用架构的CNN加速器应运而生。其中,脉动阵列架构凭借其结构简单和高并行度等优势被广泛应用。然而,由于制程变异和设备老化等因素的影响,脉动阵列容易发生Stuck-At故障(SAF),进而可能导致灾难性事故。因此,制定针对脉动阵列的容错策略显得尤为重要。然而,现有的容错策略存在时间和资源开销大、网络参数修改过多等问题。为实现高效且低开销的轻量级容错策略,拟挖掘CNN的固有容错能力,对部分影响较小的SAF进行松弛处理,以减少整体容错开销。同时,充分考虑脉动阵列的计算特性,提出了行(列)交换和权重拆分两种软硬件协同容错设计,有效缓解SAF对模型推理精度的影响。实验结果表明,相较于传统行(列)跳过策略和选择保护策略,所提软硬件协同容错策略在执行效率和模型精度恢复方面更具优势。 展开更多
关键词 卷积神经网络 容错设计 stuck-At故障 脉动阵列 卷积神经网络加速器
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