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皮纳图博火山地震震级-频度分布的空间变化

世界地震译丛 2005年第1期36卷 28-36页

作者： J．J．sánchez s．r．mcnutt J．A．Power M．Wyss 邢秀芬尹志军不详地震出版社

对菲律宾皮纳图博火山区直到山顶以下14km深度通过b值测定的地震震级-频度分布绘制成二维和三维图。我们采用最大似然法,分析了1991年6月下旬至 8月记录的1406次MD≥0．73的定位较好的地震。我们发现b值高于正常值(b=1．0), 其范围在b=1... 详细信息

对菲律宾皮纳图博火山区直到山顶以下14km深度通过b值测定的地震震级-频度分布绘制成二维和三维图。我们采用最大似然法,分析了1991年6月下旬至 8月记录的1406次MD≥0．73的定位较好的地震。我们发现b值高于正常值(b=1．0), 其范围在b=1．0至b=1．8之间。在邻近火山口西南方偏西地区计算出较低b值,而又发现两个显著高b值的异常区(b-1．7),一个位于火山口东北2 km处,深度为0～ 4 km,第二个位于火山口东南5 km处,深度在8 km以下。所选的低b值和高b值区域之间的统计学差异其置信水平确定为99%。高b值异常与早期从P波走时层析成像法研究得出的低速异常具有较好的空间相关性。我们的数据配置不适合把b值作为时间的函数的变化分析。我们推断,皮纳图博火山周围的高b值异常为裂纹密度增加的区,和／或高孔隙压力区,与邻近存在的岩浆体有关。

关键词：皮纳图博火山地震震级-频度分布空间变化 FMD

2014年1月古巴北部地震序列:不寻常的位置和意外的震源机制变化

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世界地震译丛 2020年第4期51卷 363-375页

作者： J.Braunmiller G.Thompson s.r.mcnutt 罗恒之(译) 任家琪(译) 张天中(校) 不详宁夏地震局地震分析预报中心中国地震局地球物理研究所

2014年1月9日,位于古巴北部海岸的巴哈马—古巴缝合线的沿线发生了MW5.1地震,揭示出了佛罗里达南部一个令人惊讶的地震危险源,那里的人们普遍有感。因为它的位置问题,这一事件及其余震只在遥远的地方被记录下来,从而导致高检测阈值和低... 详细信息

2014年1月9日,位于古巴北部海岸的巴哈马—古巴缝合线的沿线发生了MW5.1地震,揭示出了佛罗里达南部一个令人惊讶的地震危险源,那里的人们普遍有感。因为它的位置问题,这一事件及其余震只在遥远的地方被记录下来,从而导致高检测阈值和低定位精度。我们使用区域地震图来确定该地震序列中7个最大的地震事件的震源机制和相对位置。通过瑞利波互相关将余震相对于主震重新定位,表明这是一个密集的事件丛。在最近的佛罗里达南部061Z台站,经低通滤波(T>10s)的垂直地震波,在P波到达时,一些余震的表面波极性相对于主震出现了令人惊讶的翻转。区域矩张量反演证实了机制的改变。与全球矩心矩张量解一致,我们发现了一个主震和一次余震的机制大致东西走向的正断层。三次余震指示东西向逆断层,P轴和T轴相对于正断层事件翻转。不确定之处是,所有事件的深度都不可识别,表现为浅层断裂(小于或等于10km)。一个有趣的解释是两组地震都是在同一断层破裂,不同的机制是对动态过冲的补偿。然而,地震活动也可能稍有分离,在拉伸破裂下方出现反向机制或滑动发生在共轭断层上。沿着缝合带的浅源深度表明,更大的可能触发海啸的地震可能在古巴北部附近海域发生,这可能对当地以及佛罗里达和巴哈马造成危害。

关键词：震源机制地震序列正断层矩张量反演区域地震断层破裂地震事件浅源

Insights into optimizing exosome therapies for acute skin wound healing and other tissue repair

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Frontiers of Medicine 2024年第2期18卷 258-284页

作者： Tianjing sun Mo Li Qi Liu Anyong Yu Kun Cheng Jianxing Ma sean Murphy Patrick Michael mcnutt Yuanyuan Zhang Department of Emergency Affiliated Hospital of Zunyi Medical UniversityZunyi563003China Department of Nephrology Affiliated Hospital of Zunyi Medical UniversityZunyi563003China Division of Pharmacology and Pharmaceutical sciences School of PharmacyUniversity of Missouri-Kansas CityKansas CityMO64108USA Department of Biochemistry Wake Forest University School of MedicineWinston-SalemNC27157USA Wake Forest Institute of regenerative Medicine Wake Forest School of MedicineWinston-SalemNC27109USA

Exosome therapy holds great promise as a novel approach to improve acute skin wound *** review provides a comprehensive overview of the current understanding of exosome biology and its potential applications in acute skin wound healing and ***,small extracellular vesicles secreted by various stem cells,have emerged as potent mediators of intercellular communication and tissue *** advantage of exosome therapy is its ability to avoid potential risks associated with stem cell therapy,such as immune rejection or stem cells differentiating into unwanted cell ***,further research is necessary to optimize exosome therapy,not only in the areas of exosome isolation,characterization,and engineering,but also in determining the optimal dose,timing,administration,and frequency of exosome ***,optimization of exosome therapy is critical for the development of more effective and safer exosome-based therapies for acute skin wound healing and other diseases induced by cancer,ischemia,or *** review provides valuable insights into the potential of exosome therapy and highlights the need for further research to optimize exosome therapy for clinical use.

关键词： exosomes stem cells therapeutic impact skin wound healing

FEA-based Geometrical Modification of switched reluctance Motor for radial Force reduction

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Chinese Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： rani s Jayapragash r school of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

switched reluctance motors(srMs)are becoming increasingly popular in the automotive sector owing to their robust ***,srMs are preferred particularly for EV applications owing to their fault tolerance,magnet-free structure,and high power/torque *** main concerns of srM compared to other machines include torque ripple and *** primary cause of vibration is the radial force created by the srM.A geometry-based modification of the srM to reduce the radial force without significantly changing the average torque produced is *** primary goal is to design a 4-phase,8/6 srM with a lower radial *** possible geometrical alterations are proposed:one with square windows and the other with circular holes on the rotor *** windows are sized and positioned to avoid flux *** criteria are developed for the optimal window size and *** element analysis(FEA)modelling of the srM is used to validate its *** FEA results are compared with the performance parameters obtained using the analytical *** the multiphysics design tool ANsYs to obtain the natural frequencies and associated deformations through modal *** to the conventional geometry,the radial force is significantly reduced by providing windows.

关键词： 8/6 srM radial force modal analysis FEA analysis natural frequencies srM with windows

Kinematic analysis of flexible bipedal robotic systems

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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

Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of structural and Civil Engineering 2024年第2期18卷 170-183页

作者： r.MOHANA s.M.Leela BHArATHI Department of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolymer structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of deriving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability *** optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer *** can explain the extraordinary gain in strength of 72.11 MPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

An Efficient Modelling of Oversampling with Optimal Deep Learning Enabled Anomaly Detection in streaming Data

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China Communications 2024年第5期21卷 249-260页

作者： r.rajakumar s.sathiya Devi srinivasa ramanujan Centre SASTRA Deemed UniversityKumbakonamTamil Nadu 612001India University College of Engineering BIT CampusAnna UniversityTiruchirappalli 620024India

recently,anomaly detection(AD)in streaming data gained significant attention among research communities due to its applicability in finance,business,healthcare,education,*** recent developments of deep learning(DL)models find helpful in the detection and classification of *** article designs an oversampling with an optimal deep learning-based streaming data classification(Os-ODLsDC)*** aim of the OsODLsDC model is to recognize and classify the presence of anomalies in the streaming *** proposed Os-ODLsDC model initially undergoes preprocessing *** streaming data is unbalanced,support vector machine(sVM)-synthetic Minority Over-sampling Technique(sVM-sMOTE)is applied for oversampling ***,the Os-ODLsDC model employs bidirectional long short-term memory(Bi LsTM)for AD and ***,the root means square propagation(rMsProp)optimizer is applied for optimal hyperparameter tuning of the Bi LsTM *** ensuring the promising performance of the Os-ODLsDC model,a wide-ranging experimental analysis is performed using three benchmark datasets such as CICIDs 2018,KDD-Cup 1999,and NsL-KDD datasets.

关键词： anomaly detection deep learning hyperparameter optimization oversampling sMOTE streaming data

Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control Theory and Technology 2024年第2期22卷 326-341页

作者： T.r.Dil Kumar s.J.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. The system comprises a ball and plate mechanism and a rotary servo unit. The ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. The nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. The simplified nonlinear model of the system is obtained with suitable assumptions. The model is linearized around the operating point using the Jacobian. The validity of the developed models is investigated through correlation function analysis. The open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MATLAB/simulink platform. since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PsO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PsO) PsO PID controller

Probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： s r Wu B Q Wang Z W Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the reissner-Nordström-de sitter BH surrounded by quintessence(rN-dsQ).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dsQ under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the rN-dsQ are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant