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Kinematic analysis of flexible bipedal robotic systems

Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： R.fAZEL A.M.shafei S.R.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

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对先进多功能雷达系统行为的识别、推理与预测:综述与展望

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信号处理 2024年第1期40卷 17-55页

作者：王沙飞朱梦韬李云杰杨健李岩电磁空间认知与智能控制技术实验室北京100191 北京理工大学网络空间安全学院北京100081 北京理工大学信息与电子学院北京100081

多功能雷达(Multi-function Radar,MfR)是先进体制雷达辐射源的典型代表,其能够在雷达时间线上对多个目标调度多个同时执行的任务,具有波束指向瞬时调度、工作模式灵活动态、信号调制复杂多变的特点。随着计算智能、认知理论、数字阵列... 详细信息

多功能雷达(Multi-function Radar,MfR)是先进体制雷达辐射源的典型代表,其能够在雷达时间线上对多个目标调度多个同时执行的任务,具有波束指向瞬时调度、工作模式灵活动态、信号调制复杂多变的特点。随着计算智能、认知理论、数字阵列、软件自定义及硬件可重构系统的不断发展,先进多功能雷达系统自由度和性能潜力不断提升,给现代电子侦察与对抗系统带来了巨大挑战。本文首先较为全面地给出了雷达系统行为的分类,依据雷达系统行为活动的内容与目的将雷达行为分为推理行为、决策行为和动作行为三类,并从雷达方和侦察方两个不同视角对上述三类行为进行了归类划分。然后围绕对先进MfR系统行为的感知识别难题,从侦察方视角对多功能雷达行为进行分析识别的侦察分析模型建模表征、雷达系统外显行为识别、内隐行为推理以及对未来行为预测等四方面对相关基础理论、实现技术的研究进行了全面梳理,并对未来研究面临的挑战和重点进行了分析,旨在为针对先进MfR系统行为相关的后续理论研究与技术发展提供有益参考。

关键词：多功能雷达侦察分析模型行为识别行为推理行为预测

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HER2免疫组织化学结果为0的乳腺癌HER2 mRNA定量分析

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中华病理学杂志 2024年第5期53卷 464-469页

作者：孙铭晨武莎斐蔡宇梦刘媛媛李凯咪赵大春曾瑄中国医学科学院、北京协和医学院、北京协和医院病理科北京100730

目的探讨HER2免疫组织化学(IHC)检测结果为0乳腺癌患者HER2 mRNA的表达特征,初步分析以HER2基因表达水平分层乳腺癌HER2超低表达和HER2无表达(IHC无染色)的可行性。方法收集北京协和医院2020年1月至2023年3月手术的甲醛固定石蜡包埋的... 详细信息

目的探讨HER2免疫组织化学(IHC)检测结果为0乳腺癌患者HER2 mRNA的表达特征,初步分析以HER2基因表达水平分层乳腺癌HER2超低表达和HER2无表达(IHC无染色)的可行性。方法收集北京协和医院2020年1月至2023年3月手术的甲醛固定石蜡包埋的浸润性乳腺癌组织标本41例,包括21例HER2 IHC 1+和20例HER2 IHC 0(HER2超低表达12例,HER2无表达8例)。采用数字PCR方法,以荧光fAM(HER2)/VIC(内参基因)比值计算HER2 mRNA水平。结果HER2 IHC 1+、HER2超低表达及HER2无表达的HER2 mRNA表达分别为0.30~1.78(平均0.90,中位0.82)、0.55~1.51(平均0.93,中位0.90)及0.22~0.78(平均0.41,中位0.36)。每组HER2 mRNA表达的平均值和中位值,HER2 IHC 1+和HER2超低表达之间差异无统计学意义(P=0.757);HER2 IHC 1+与HER2无表达及HER2超低表达与HER2无表达之间差异有统计学意义(分别P=0.002,P=0.001)。结论根据HER2 mRNA水平,HER2无表达与HER2弱表达(HER21+和HER2超低表达)属于两组不同的肿瘤;而HER21+和HER2超低表达可能是同一组肿瘤。有必要进一步验证以HER2 mRNA精细分层HER2弱表达的能力及确定阈值。

关键词：乳腺肿瘤基因 erbB-2 免疫组织化学超低表达

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回顾性分析真实世界中HER2低表达乳腺癌的临床病理特征

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中华病理学杂志 2024年第7期53卷 691-696页

作者：李凯咪武莎斐孙铭晨张鸿曦腾新仪刘媛媛梁智勇曾瑄中国医学科学院北京协和医学院北京协和医院病理科北京100730

目的探讨HER2低表达乳腺癌的特征。方法收集北京协和医院2019年4月至2022年7月3422例存档的浸润性乳腺癌患者临床资料,其中包括具有完整新辅助化疗信息的患者136例。所分析的指标包括年龄、雌激素受体和孕激素受体状态、HER2状态、Ki-6... 详细信息

目的探讨HER2低表达乳腺癌的特征。方法收集北京协和医院2019年4月至2022年7月3422例存档的浸润性乳腺癌患者临床资料,其中包括具有完整新辅助化疗信息的患者136例。所分析的指标包括年龄、雌激素受体和孕激素受体状态、HER2状态、Ki-67阳性指数、组织学分型、肿瘤分化、肿瘤大小及淋巴结转移,以及病理完全缓解(pathologic complete response,pCR)率。结果在未接受新辅助治疗的3286例乳腺癌中,检出免疫组织化学(IHC)0者616例(616/3286,18.7%)、IHC 1+者1047例(1047/3286,31.9%)、IHC 2+者1099例(1099/3286,33.4%)及IHC 3+者524例(524/3286,15.9%)。在IHC 2+组中1070例乳腺癌进行荧光原位杂交(fISH)检测,其中HER2扩增者161例。在本队列中,HER2低表达(IHC 1+和IHC 2+/fISH-)乳腺癌共计1956例。与HER2 IHC 0组相比,HER2低表达好发于50岁以上(P=0.008)、激素受体阳性(P0.05)。新辅助化疗后,HER2低表达组的pCR率低于HER2 IHC 0组(分别为13.3%和23.9%),但差异无统计学意义(P>0.05);尽管按激素受体状态分类,也都观察到HER2低表达组的pCR率略低于HER2 IHC 0组,但差异仍无统计学意义(P>0.05)。结论HER2低表达组乳腺癌的临床病理特征不同于HER2 IHC 0组。准确区分HER2低表达和HER2 IHC 0并探索其是否为一个独立的生物学实体是有必要的。

关键词：乳腺肿瘤基因,erbB-2 低表达

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混合教学模式下案例教学法结合超星学习通在口腔正畸学教学中的应用实践及分析

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卫生职业教育 2024年第12期42卷 74-76页

作者：李雪周芳翟莎菲柴娟张佳西安医学院口腔医学院陕西西安710021

为研究混合教学模式下案例教学法与超星学习通在口腔正畸学教学中的运用,将西安医学院口腔医学院2017级和2018级本科生纳入研究范围,并将其设为对照组与实验组。在这两组中,对照组使用常规的教学方法,而实验组则使用混合教学方法。比较... 详细信息

为研究混合教学模式下案例教学法与超星学习通在口腔正畸学教学中的运用,将西安医学院口腔医学院2017级和2018级本科生纳入研究范围,并将其设为对照组与实验组。在这两组中,对照组使用常规的教学方法,而实验组则使用混合教学方法。比较两组学生的教学满意度、学业表现、综合能力以及对教学方法的评估。教学实践表明,在高校口腔正畸学教学中采用混合式教学法,能够提高学生解决实际问题的能力及考试成绩,从而进一步提高教学质量和效率,值得推广。

关键词：混合式教学案例教学法口腔正畸学

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Development of a Medium Voltage, High Power, High frequency four-Port Solid State Transformer

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 95-104页

作者： Ahmad El shafei Saban Ozdemir Necmi Altin Garry Jean-Pierre Adel Nasiri IEEE Department of Electrical Engineering University of Wisconsin Milwaukee Department of Electrical-Electronic Engineering Faculty of TechnologyUniversity of Gazi Department of Electrical Engineering University of South Carolina

The power and voltage levels of renewable energy resources is growing with the evolution of the power electronics and switching module *** that,the need for the development of a compact and highly efficient solid-state transformer is becoming a critical task in-order to integrate the current AC grid with the new renewable energy *** objective of this paper is to present the design,implementation,and testing of a compact multi-port solid-state transformer for microgrid integration *** proposed system has a four-port transformer and four converters connected to the *** transformer has four windings integrated on a single common ***,it can integrate different renewable energy resources and energy storage *** port has a rated power of 25 kW,and the switching frequency is pushed to 50 k *** ports are chosen to represent a realistic industrial microgrid model consisting of grid,energy storage system,photovoltaic system,and *** grid port is designed to operate at 4.16 k VAC corresponding to 7.2 kV DC bus voltage,while the other three ports operate at 500 ***,the grid,energy storage and photovoltaic ports are active ports with dual active bridge topologies,while the load port is a passive port with full bridge rectifier *** proposed design is first validated with simulation results,and then the proposed transformer is implemented and *** results show that the designed system is suitable for 4.16 k VAC medium voltage grid integration.

关键词： Co-simulation high frequency high power medium voltage microgrid Multi-port solid state transformer

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Sequence stratigraphic evaluation for the Abu Madi formation,Abu Madi/El Qar'a/Khilala gas fields,onshore Nile Delta,Egypt

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Petroleum Research 2023年第4期8卷 514-523页

作者： farouk I.Metwalli Amir Ismail M.S.Metwally Ibrahim M.El shafei Geology Department Faculty of ScienceHelwan UniversityCairoEgypt Desert Research Center CairoEgypt Petrobel Oil Company CairoEgypt

The present study aims to integrate a large set of geological and geophysical data into a comprehensive model describing the depositional features of the Abu Madi/El Qar'a/Khilala gas *** model is based on the sequence stratigraphic framework of the Abu Madi formation defined using cores,well logs,and time-migrated seismic *** trace attribute sections and relative acoustic impedance sections are also used.A possible depositional pattern for the main Level Ill is established,based on the lithological and petrophysical information derived from the seismic data *** Abu Madi for-mation can be regarded as a depositional sequence recording the progressive drowning of the incised *** sequence is bounded at the base by an erosional unconformity,created by a drop in the level of the Late Messinian Sea,and at the top by a drowning unconformity related to the Early Pliocene *** bottom of Level II divides the Abu Madi sequence into two smaller *** both sequences,gas-bearing traps can be found in the Lowstand Systems Tracts,represented by the fluvial Level Ill and fluvial-deltaic Level Il,respectively.

关键词： Abu Madi gas field El Qar'a area Khilala area Sequence stratigraphy analysis Onshore Nile Delta Abu Madi formation

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Modification of Serum Galectin-3 and Reversal of Cardiac Remodeling following Pediatric Transcatheter Atrial Septal Defect Closure

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Congenital Heart Disease 2022年第2期17卷 173-185页

作者： Omnia shafei Alyaa A.Kotby Mona MEl Ganzoury Nevin M.Habeeb Eman Elsayed Department of Pediatrics Faculty of MedicineAin Shams UniversityCairoEgypt Children’s Hospital Cardiology UnitAin Shams University HospitalsCairoEgypt

Objectives:We aimed to evaluate the effect of percutaneous atrial septal defect(ASD)closure in children using right heart indices and serum galectin-3(Gal-3),as potential biomarkers of right heart ***:This case–control prospective study included 40 children with ASD and 25 control *** echocardiographic evaluation was performed before the procedure,as well as 24 h,1 month,and 6 months after *** Gal-3 was measured before,and 1 month after the ***:Serum Gal-3 concentration,right atrial(RA)dimensions,right ventricular(RV)dimensions,indexed RA area,and right index of myocardial performance(RIMP)were significantly increased in children with ASD compared with control subjects while tricuspid annular plane systolic excursion(TAPSE)was significantly *** months after closure,RA,and RV dimensions significantly decreased and RVfunction improved(RIMP decreased and TAPSE increased).Gal-3 oncentration significantly decreased 1 month after ASD closure,but it did not reach normal range compared with control subjects.A positive correlation between Gal-3 and age at closure,RA area,RV dimensions,and RIMP was observed.A positive correlation was observed between the decrease in Gal-3 concentration and the decrease in RA area and RV dimensions 1 month after ASD closure.A significant negative correlation was observed between TAPSE and Gal-3 concentration before and after ***:Percutaneous ASD closure can improve right-sided indices and decrease serum Gal-3 ***-3 can be used as a sensitive biomarker of right heart remodeling,with a decrease in Gal-3 concentration suggesting reversal of maladaptive remodeling.

关键词： Percutaneous device closure Galectin-3 cardiac remodeling children atrial septal defect

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The role of nitric oxide in the dorsomedial periaqueductal gray(dmPAG)column in cardiovascular responses in urethane-anesthetized male rats

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Animal Models and Experimental Medicine 2022年第6期5卷 557-564页

作者： Mohammad Najaftomaraei Atiyeh Ghorbani Alireza Rahimi Reza Mohebbati Sogol Sherkat Mohammad Naser shafei Department of Physiology Faculty of MedicineMashhad University of Medical SciencesMashhadIran Material Science and Metallurgy Engineering Islamic Azad University-Karaj BranchKarajIran Department of Physiology Faculty of MedicineGonabad University of Medical SciencesGonabadIran Applied Biomedical Research Center Mashhad University of Medical SciencesMashhadIran Department of Physiology School of MedicineSabzevar University of Medical SciencesSabzevarIran Division of Neurocognitive Sciences Psychiatry and Behavioral Sciences Research CenterMashhad University of Medical SciencesMashhadIran

Background:The dorsomedial periaqueductal gray(dmPAG)is a mesencephalic area and has numerous functions including cardiovascular *** nitric oxide(NO)is present in the dmPAG,here we investigate,the probable cardiovascular effect of NO in the ***:five groups(n=6 for each group)were used as follows:(1)control;(2)L-NAME(N^(G)-nitro-L-arginine methyl ester,a NO synthase inhibitor,90 nmol);(3)Larginine(L-Arg,a precursor for NO,60 nmol);(4)Sodium nitroprusside(SNP,a NO donor,27 nmol);and(5)L-Arg+*** cardiovascular parameters were recorded by a Power Lab device after cannulation of the femoral *** were injected using a stereotaxic *** changes(Δ)in systolic blood pressure(SBP),mean arterial pressure(MAP),and heart rate(HR)were calculated at different times and compared to the control ***:Microinjection of L-NAME significantly increased ΔSBP,ΔMAP,and ΔHR more than saline(from pficantly increased ΔHR(pficantly increased(from pficantly as with L-NAME *** of SNP significantly decreased ΔSBP and ΔMAP more than in the control and L-NAME groups(from pffect on cardiovascular responses in anesthetized rats.

关键词： blood pressure dorsomedial periaqueductal gray L-arginine L-NAME nitric oxide

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Improved particle filtering techniques based on generalized interactive genetic algorithm

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Journal of Systems Engineering and Electronics 2016年第1期27卷 242-250页

作者： Yan Zhang shafei Wang Jicheng Li ATR Key Laboratory National University of Defense Technology Changsha 410073 China Institute of North Electronic Equipment Beijing 100191 China

This paper improves the resampling step of particle filtering（Pf） based on a broad interactive genetic algorithm to resolve particle degeneration and particle *** target tracking in image processing,this paper uses the information coming from the particles of the previous fame image and new observation data to self-adaptively determine the selecting range of particles in current fame *** improved selecting operator with jam gene is used to ensure the diversity of particles in mathematics,and the absolute arithmetical crossing operator whose feasible solution space being close about crossing operation,and non-uniform mutation operator is used to capture all kinds of mutation in this *** result of simulating experiment shows that the algorithm of this paper has better iterative estimating capability than extended Kalman filtering（EKf）,Pf,regularized partide filtering（RPf）,and genetic algorithm（GA）-Pf.

关键词： particle filtering(Pf) particle degeneration particle shortage broad interactive genetic algorithm

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