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Neural regeneration research 2024年第7期19卷 1419-1420页

作者： Muhammad N.Arshad Janice r.Naegele Department of Biology Wesleyan UniversityMiddletownCTUSA Department of Neuroscience Tufts University School of MedicineBostonMAUSA

Temporal lobe epilepsy(TLE) is a common type of focal epilepsy characterized by seizure foci within the temporal *** surgical resection of the foci is an established and effective approach for controlling seizures,both temporal lobes cannot be removed,due to their prominent roles in learning and ***,seizures induce changes to the temporal lobes that contribute to hyperexcitability,including mossy fiber sprouting,astrogliosis.

关键词： epilepsy progenitor seizures

Integralinput-to-statestability ystemswithsmalldelays Integral input-to-state stability of systems with small delays

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Control Theory and Technology 2024年第3期22卷 455-467页

作者： r.H.Harsha Nawarathna Yuandan Lin Yuan Wang Department of Mathematical Sciences Florida Atlantic UniversityBoca RatonFL 33431USA

We consider how small delays affect the integral-input-to-state stability(iss)property for a *** result is similar to the input-to-state stability(Iss)result obtained in[1]:the iss property will be preserved in a practical and semi-global manner if the delay interval is small ***,since the iss quantifies the robust stability in terms of a generalized Li norm of the inputs instead of a generalized Loo norm of the inputs for the Iss case,the techniques and proofs for the Iss case do not apply to the iss case *** the proofs in[1]are based on the lyapunov-razumikhin approach,our proofs are based on the iss-lyapunov functions for the zero-delay *** addition to the interest by its own in showing how the iss property is affected by small delays,the result also serves to the study of the iss property for singularly perturbed systems.

关键词： Integral-input-to-state stability Nonlinear systems Small delays lyapunov method

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

Design of a large-scale model for wind tunnel test of a multiadaptive flap concept

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Chinese Journal of Aeronautics 2024年第2期37卷 58-80页

作者： Mürüvvet Sinem SICIM DEMIrCI rosario PECOrA Metin Orhan KAYA Aeronautical Engineering Department Istanbul Technical UniversityIstanbulTurkey Industrial Engineering Department University of Naples Federico IINapoliItaly

The design and application of morphing systems are ongoing issues compelling the aviation *** Clean Sky-program represents the most significant aeronautical research ever launched in Europe on advanced technologies for greening next-generation *** primary purpose of the program is to develop new concepts aimed at decreasing the effects of aviation on the environment,increasing reliability,and promoting eco-friendly *** ambitions are pursued through research on enabling technologies fostering noise and gas emissions reduction,mainly by improving aircraft aerodynamic *** the Clean Sky framework,a multimodal morphing flap device was designed based on tight industrial requirements and tailored for large civil aircraft *** flap is deployed in one unique setting,and its cross section is morphed differently in take-off and landing to get the necessary extra lift for the specific flight ***,during the cruise,the tip of the flap is deflected for load control and induced drag *** manufacturing the first flap prototype,a high-speed(Ma=0.3),large-scale test campaign(geometric scale factor 1:3)was deemed necessary to validate the performance improvements brought by this novel system at the aircraft *** the other hand,the geometrical scaling of the flap prototype was considered impracticable due to the unscalability of the embedded mechanisms and actuators for shape ***,a new architecture was conceived for the flap model to comply with the scaled dimensions requirements,withstand the relevant loads expected during the wind tunnel tests and emulate the shape transition capabilities of the true-scale *** strategies were developed to effectively morph the model during wind tunnel tests while ensuring the robustness of each morphed configuration and maintaining adequate stiffness levels to prevent undesirable deviations from the intended aerodynamic ***,

关键词： Morphing structures Smart aircraft Morphing flap Adaptive systems Finger-like ribs Wind tunnel tests Large-scale morphing archi-tectures Variable camber airfoil

西太平洋麦哲伦海山群Hemler、Vlinder和Il’ichev海山熔岩的成因及其形成的深部动力学机制

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中国科学：地球科学 2024年第6期54卷 1883-1900页

作者：位荀张艳石学法张辉自然资源部第一海洋研究所海洋地质与成矿作用重点实验室青岛266061 青岛海洋科技中心海洋地质过程与环境功能实验室青岛266237 山东省深海矿产资源开发重点实验室(筹) 青岛266061

经典的“地幔柱假说”能够很好解释年龄随空间位置线性变化的大洋板内火山链的成因.而位于西太平洋的众多海山群,空间分布广、年龄-位置关系杂乱,很难用经典的“地幔柱假说”来解释,其成因存在争议.本研究选择西太平洋麦哲伦海山群Hemle... 详细信息

经典的“地幔柱假说”能够很好解释年龄随空间位置线性变化的大洋板内火山链的成因.而位于西太平洋的众多海山群,空间分布广、年龄-位置关系杂乱,很难用经典的“地幔柱假说”来解释,其成因存在争议.本研究选择西太平洋麦哲伦海山群Hemler、Vlinder和Il’ichev海山熔岩,对其进行40Ar-39Ar年代学、主量和微量元素以及Sr-Nd-Pb-Hf同位素分析,来揭示其岩石成因和形成的深部动力学机制. Hemler、Vlinder和Il’ichev海山熔岩属于碱性玄武岩、碧玄岩/霞石岩和粗面岩, MgO>8wt.%的熔岩具有较高的CaO、FeOT和TiO2含量,是碳酸盐化榴辉岩熔融的熔体与橄榄岩反应的产物.这些熔岩具有较高的Zr/Hf比值(40.6~45.2)和Zr-Hf负异常,指示它们的地幔源区存在碳酸盐组分. Hemler、Vlinder和Il’ichev海山熔岩富集不相容元素,其Sr-Nd-Pb-Hf同位素显示EM1(1型富集地幔)特征,与rarotonga和Samoa热点相似.虽然产出于同一个海山, Il’ichev碱性玄武岩与Il’ichev碧玄岩的同位素组成明显不同:前者具有更为亏损的Sr-Nd-Hf同位素特征.结合板块构造恢复结果, Hemler(100.1Ma)、Vlinder造盾前(100.2Ma)和造盾期后((87.5±0.4)Ma)以及Il’ichev((56.4±1.2)Ma)海山熔岩的形成时间明显偏离了南太平洋Macdonald、Arago、rarotonga和Samoa热点的运移轨迹,因此它们并非来源于深部地幔柱的直接熔融,更可能是浅部过程的产物.麦哲伦海山群所在的大洋板块的一个典型特征是:岩石圈断裂带在该区域广泛分布.我们提出,在中白垩世当麦哲伦海山群所在的太平洋板块经过rarotonga地幔柱上方时, rarotonga地幔柱直接熔融形成Vlinder(造盾期)、Pako和Ioah海山.随着地幔对流分散在周围软流圈中的rarotonga和Samoa地幔柱物质,在岩石圈裂隙处发生减压熔融,形成Hemler和Vlinder造盾前和造盾期后熔岩;Il’ichev海山碱性玄武岩和碧玄岩是岩石圈裂隙诱发的软流圈中不均一富集组分熔融的产物.这种不均一组分最可能是滞留在软流圈中的不同地幔柱的物质,也有可能是残留在软流圈中的再循环的地球表层物质.

关键词：地幔柱麦哲伦海山链碳酸盐化地幔热点岩石圈伸展

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.I.KUZMINA Y.V.OSIPOV A.r.PESTErEV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

边缘下皮质(IL)的动态改变以及IL对前边缘皮质(PL)的调控参与大鼠慢性炎症痛

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中国疼痛医学杂志 2024年第7期30卷 158-158页

作者：刘风雨(译) 北京大学神经科学研究所

慢性疼痛是临床的常见病。内侧前额叶皮质(medial prefrontal cortex,mPFC)参与慢性疼痛发病机制。前边缘皮质(prelimbic cortex,PL)是mPFC的一个核心亚区,介导慢性疼痛。边缘下皮质(IL)是mPFC的另一个亚区,也能够调控伤害性反应。神经... 详细信息

慢性疼痛是临床的常见病。内侧前额叶皮质(medial prefrontal cortex,mPFC)参与慢性疼痛发病机制。前边缘皮质(prelimbic cortex,PL)是mPFC的一个核心亚区,介导慢性疼痛。边缘下皮质(IL)是mPFC的另一个亚区,也能够调控伤害性反应。神经解剖学研究表明,IL深层的兴奋性锥体神经元通过支配PL深层的抑制性中间神经元,进而作用到PL局部的锥体神经元上,调控PL的功能。IL、PL以及IL-PL环路如何参与慢性疼痛的发病机制,不甚清晰。研究者采用完全弗氏佐剂(complete Freund's adjuvant,CFA)建立的大鼠慢性炎症痛模型,结合体电生理记录和化学遗传学等方法,深入解析IL、PL及其环路在慢性疼痛中的作用。

关键词：中间神经元完全弗氏佐剂慢性疼痛神经解剖学锥体神经元大鼠发病机制

Hybrid LES/rANS Simulations of Compressible Flow in a Linear Cascade of Flat Blade Profiles

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Journal of Thermal Science 2024年第5期33卷 1839-1850页

作者： Jaromír PrIHODA Petr STrAKA David SIMUrDA Petr SIDLOF Jan LEPICOVSKY Institute of Thermomechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aerospace research and Test Centre Beranovych 13019905 PragueCzech Republic Technical University of Liberec Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The paper reports on 3D numerical simulations of unsteady compressible airflow in a blade cascade consisting of flat profiles using a hybrid LES/rANS approach including a transition *** a first step towards simulation of blade flutter in turbomachinery,various incidence angle offsets of the middle blade were *** simulations were run for the flow regime characterized by outlet isentropic Mach number M_(is)=0.5and zero *** results of the LES/rANS simulations(pressure and Mach number distributions)were compared to a baseline rANS model,and to experimental data measured in a high-speed wind *** numerical results show that both methods overpredict flow separation taking place at the leading *** this regard,the hybrid LES/rANS method does not provide superior results compared to the traditional rANS ***,the LES/rANS results also capture vortex shedding from the blunt trailing *** frequency of the trailing edge vortex shedding in CFD simulations matches perfectly the spectral peak recorded during wind tunnel measurements.

关键词： numerical simulation blade cascade hybrid LES/rANS

Multi-objective method of selecting performance-based local climatic zones using binomial logistic regression in warm and humid climate

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Frontiers of Architectural research 2024年第1期13卷 184-200页

作者： G.r.Madhavan Dorairaj Kannamma Department of Architecture National Institute of TechnologyTiruchirappalliTamil Nadu 620015India

Urban agglomeration is a serious concern due to its high energy usage and impact on the local *** countries strive to determine the development path to optimize energy *** present study aims to examine the local climatic zones(LCZs)performance in warm and humid climate through a multi-objective approach for the residential *** performance is assessed by evaluating the urban microclimate and cooling load consumption for both summer and winter months using binomial logistic *** study concludes that LCZ 2_(3)(compact mid-rise with open low-rise)and LCZ 6_(B)(open low-rise with scattered trees)perform better for 80%and 50%of total hours in warm and humid *** also proves the presence of significant performance differences between mid-rise and low-rise *** intra-zonal differences between the climatic variables are higher than the inter-zonal differences due to the impact of land surface temperature(LST).The high aspect ratio and low sky view factor of LCZ 2_(3) help the residents in that morphology in enhancing better thermal comfort and reducing cooling load *** present study contributes to building regulation policymakers by providing information on the suitable morphology for warm and humid climate.

关键词： LCZ Outdoor thermal comfort Cooling load LST and urban morphology indicators