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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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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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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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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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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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基于多状态故障树的北极船舶冰困风险预警模型
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作者 姜河蓉 吴铭燕 +2 位作者 付姗姗 敖晨韵 王胜正 《极地研究》 北大核心 2025年第3期574-584,共11页
北极海冰状态和气候变化给船舶航行安全保障带来了挑战,为降低船舶冰困的风险,保障船员和船舶安全,开展北极航行船舶冰困风险预警研究具有重要意义。本文从气候环境、海况、冰况、船舶和人为因素等方面对诱发北极航行船舶冰困的风险因... 北极海冰状态和气候变化给船舶航行安全保障带来了挑战,为降低船舶冰困的风险,保障船员和船舶安全,开展北极航行船舶冰困风险预警研究具有重要意义。本文从气候环境、海况、冰况、船舶和人为因素等方面对诱发北极航行船舶冰困的风险因素进行了识别,结合船舶航行分级预警规则构建了基于多状态故障树的北极航行船舶冰困风险预警模型,同时对海冰环境、船舶运行状态等组合场景下的船舶冰困风险进行了概率预测。本预警模型由16个节点(包含12个基本事件、3个中间事件和1个顶事件)组成,且节点设定了报警、警告、提醒和安全4种状态等级,可根据北极航行船舶实测数据进行冰困风险动态预警。 展开更多
关键词 船舶冰困 多状态故障树 风险预警 北极航行
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滞针结合面针应用于面部美容22例
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作者 李孟汉 张元 +2 位作者 冉大为 杨欣铭 李静宜 《中国针灸》 北大核心 2025年第1期41-44,共4页
目的:观察滞针结合面针应用于面部美容的临床疗效。方法:对22例存在面部衰老症状的女性患者给予滞针结合面针治疗,其中滞针取双侧太阳透下关、颊车透大迎和迎香,每周针刺1次;面针取印堂、阿是穴(鼻唇沟处)及双侧阳白、颧髎、四白、下关... 目的:观察滞针结合面针应用于面部美容的临床疗效。方法:对22例存在面部衰老症状的女性患者给予滞针结合面针治疗,其中滞针取双侧太阳透下关、颊车透大迎和迎香,每周针刺1次;面针取印堂、阿是穴(鼻唇沟处)及双侧阳白、颧髎、四白、下关、地仓、颊车、大迎、人迎,每周针刺2次。共治疗4周。于治疗后评定患者整体美学改善量表(GAIS)评分,观察患者治疗前后皱纹严重程度评定量表(WSRS)评分,并于治疗前后进行皮肤特征定量分析。结果:治疗后,22例患者完全改善3例,明显改善15例,部分改善4例,无改善0例;WSRS评分及皱纹、纹理、毛孔评分较治疗前降低(P<0.01)。结论:滞针结合面针可有效改善面部衰老症状。 展开更多
关键词 美容 滞针 面针
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面向“卡脖子”技术创新的公共采购政策设计研究——以光刻机制造技术为例
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作者 刘京 苏新纪 +1 位作者 康晓玲 张霞 《西安电子科技大学学报(社会科学版)》 2025年第2期25-35,共11页
为了进一步加快面向“卡脖子”问题的技术创新,需要推动相关创新政策的迭代升级。本文以光刻机制造技术为例,以一种新兴的创新政策——创新导向型公共采购为工具,采用方法论拼接探究了针对“卡脖子”技术的精准干预设计问题。首先,在卡... 为了进一步加快面向“卡脖子”问题的技术创新,需要推动相关创新政策的迭代升级。本文以光刻机制造技术为例,以一种新兴的创新政策——创新导向型公共采购为工具,采用方法论拼接探究了针对“卡脖子”技术的精准干预设计问题。首先,在卡点识别的基础上,基于“问题-解空间”将卡点细分为四种类型——窒息性卡点、紧缩性卡点、急发性卡点和消耗性卡点;然后,在创新导向型公共采购类型学和产业界政策需求分析的基础上,从创新政策精细化和动态化两个方面,提出了针对光刻机制造技术的定制化政策设计方案。在精细化方面,本文提出了针对四类不同卡点的政策工具选择与组合设计;在动态化方面,本文提出了产业优先型、技术优先型、均衡发展型和赛道变换型四条政策动态调整路径。本研究不仅提升了对“卡脖子”技术识别的细粒度,也为我国进一步推动“卡脖子”技术创新政策的迭代升级提供了新思路。 展开更多
关键词 卡点 “卡脖子”技术 问题-解空间 创新导向型公共采购 光刻机制造技术
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元坝气田水平井卡埋钻故障原因及处置
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作者 全家正 程佳豪 《科技和产业》 2025年第18期211-216,共6页
元坝气田某口水平井在钻进过程中发生了埋卡故障,造成了严重的经济损失。为了明确该地区水平井卡埋钻故障原因,梳理了卡埋钻故障发生及处理过程,分析故障发生的可能主要原因:长兴组与飞一段地层压力系数相差大;飞一地层泥质灰岩及泥质... 元坝气田某口水平井在钻进过程中发生了埋卡故障,造成了严重的经济损失。为了明确该地区水平井卡埋钻故障原因,梳理了卡埋钻故障发生及处理过程,分析故障发生的可能主要原因:长兴组与飞一段地层压力系数相差大;飞一地层泥质灰岩及泥质条带吸水膨胀使泥岩强度降低,影响井眼稳定性;排量小环空大不利于岩屑携带。针对元坝气田井下复杂情况,提出卡埋钻事故主要预防措施:钻井施工过程中需要更高密度支撑井壁,并且控制钻井液失水性能防塌;设置合适的排量、转速、划眼速度;在钻井施工前开展钻具强度评估并分析可能的失效结果。相关研究结果为该地区水平井钻井施工提供借鉴。 展开更多
关键词 元坝气田 水平井 卡埋钻 钻具 打捞
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基于有监督与无监督算法的卡钻智能诊断分析
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作者 宋先知 王易玮 +2 位作者 杨彦龙 刘慕臣 祝兆鹏 《新疆石油天然气》 2025年第2期24-34,共11页
在钻井工程中,卡钻作为常见的井下复杂工况之一严重影响钻井效率,卡钻监测对保障钻井作业的安全与效率至关重要。近年来,人工智能技术的快速发展为卡钻监测提供了新的思路,而现有的卡钻智能监测研究多聚焦单一无监督或有监督算法的优化... 在钻井工程中,卡钻作为常见的井下复杂工况之一严重影响钻井效率,卡钻监测对保障钻井作业的安全与效率至关重要。近年来,人工智能技术的快速发展为卡钻监测提供了新的思路,而现有的卡钻智能监测研究多聚焦单一无监督或有监督算法的优化与应用,针对两类算法在卡钻监测场景中的系统性对比研究仍存空白。通过距离相关系数筛选钻头位置、大钩高度、转盘扭矩等多维度钻井参数为研究对象,构建包含经典无监督算法模型(自编码器、K均值聚类、DBSCAN聚类)和有监督算法模型(支持向量机、随机森林、长短期记忆网络)的对比评估体系,对两类算法的卡钻趋势判断能力开展性能分析。结果表明,与有监督算法模型相比,无监督算法模型的卡钻监测平均准确率提高12.5%、平均虚警率降低37.1%、平均漏警率降低27.6%,无监督算法模型在小样本及无机理约束情况下更有优势。研究结果可为钻井工程卡钻智能监测的模型选型与优化提供参考,推动无监督算法模型在卡钻风险监测中的实际应用。 展开更多
关键词 卡钻监测 机器学习 无监督算法模型 有监督算法模型 钻井
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