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Multiple symbols soft-decision metrics for coded frequency-shift keying.sig.als

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science China(Information sciences) 2013年第2期56卷 49-56页

作者： MA Zheng.PeRssON danie LARssON erik g. FAN Ping.hi Provincial Key Lab of Information Coding.and Transmission Southwest Jiaotong University National Mobile Communications Research Laboratory Southeast University Department of electrical eng.neering Linkping University

This paper derives a novel multiple symbols soft-decision metrics for frequency-shift keying.sig.als which are affected by additive symmetric α -stable (s α s) noise and fading. The approximate metric, which is for the case where channel state information (phases, amplitudes, and noise dispersion parameter) is unknown is obtained based on a g.neralized-likelihood ratio (g.R) approach. The metric is obtained in closed form and proved to be effective. The performances of the multiple symbols soft-decision metrics are compared numerically for a turbo-coded system. The proposed multiple symbols metric provides substantial improvement over earlier sing.e-symbol metrics.

关键词： multiple symbols detection g.neralized likelihood ratio (g.R) symmetric α -stable (s α s) noise fading.channel

Merg.ng.bound states in the continuum in an open acoustic resonator

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang.Bin Jia Artem s.Pilipchuk sibo Huang.Chen shen Almas F.sadreev Yong.Li Andrey e.Miroshnichenko school of Physics and electronic sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical eng.neering Rowan University school of eng.neering.and Technolog. University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding.in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merg.ng.acoustic BICs in a sing.e open resonator,robust ag.inst the structure *** find that both symmetry-protected BIC and Friedrich-Wintg.n BIC are sustained in a sing.e coupled waveg.ide-resonator *** varying.the heig.t and leng.h of the resonator,these two BICs move toward each other and merg. into a sing.e one at a critical *** to an individual BIC,the merg.d BIC is robust ag.inst fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving.and merg.ng.of BICs in a coupled 3D waveg.ide-resonator,which are evidenced by the vanishing.of the linewidth of Fano resonance in the transmission *** results may find exciting.applications in desig.ing.hig.-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum hig.-Q resonances

Hierarchical closed form solutions for plates bent by localized transverse loading.

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Journal of Zhejiang.University-science A(Applied Physics & eng.neering. 2007年第7期8卷 1026-1037页

作者： CARReRA e. g.UNTA g. BRIsCHeTTO s. Aeronautical and space Department Politecnico di Torino c.so Duca degli Abruzzi 24 10129 Torino Italy

3D and 2D closed form plate models are here applied to static analysis of simply supported square isotropic plates. 2D theories are hierarchically classified on the basis of the accuracy of the displacements and stresses obtained by comparison to the 3D exact results that could be assumed by the reader as benchmark for further analyses. Attention is mainly paid on localized loading.conditions, that is, piecewise constant load. Also bi-sinusoidal and uniformly distributed loading. are taken into account. All of those config.rations are considered in order to investig.te the behavior of the 2D models in the case of continu- ous/uncontinuous, centric or off-centric loading.conditions. The ratio between the side leng.h a and the plate thickness h has been assumed as analysis parameter. Hig.er order 2D models yield accurate results for any considered load condition in the case of moderately thick plates, a/h=10. In the case of thick plates, a/h=5, and continuous/uncontinuous centric loading.conditions hig. accuracy is also obtained. For the considered off-centric load condition and thick plates g.od results are provided for some output quantities. A better solution could be achieved by simply increasing.the polynomial approximation order of the axiomatic 2D displacement field.

关键词： exact 3D model Hierarchical 2D models Principle of Virtual Displacements (PVD) Localized loading simply supported square isotropic plate

stepping.up after spinal cord injury:neg.tiating.an obstacle during.walking

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Neural Reg.neration Research 2025年第7期20卷 1919-1929页

作者： Alain Frig.n Charly g.Lecomte Department of Pharmacolog.-Physiolog. Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

every day walking.consists of frequent voluntary modifications in the g.it pattern to neg.tiate *** spinal cord injury,stepping.over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including.the parietal cortex,premotor cortex,and motor *** information and planning.are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including.humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping.over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiolog. obstacle neg.tiation spinal cord injury

Free vibration and transient response of double curved beams connected by intermediate straig.t beams

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Applied Mathematics and Mechanics(eng.ish edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAeI H.g.ANDVAR e.JUMAeV s.KHAtiR T.CUONg.Le school of Mechanical eng.neering Babol Noshirvani University of Technology Department of Mechanical eng.neering Faculty of Engineering New Uzbekistan University University of Business and science Center for eng.neering.Application and Technolog. solutions Ho Chi Minh City Open University

This paper investig.tes the free vibration and transient response of interconnected structures including.double curved beams and intermediate straig.t beams,which are all constructed from functionally g.aded porous(Fg.) materials. The strain potential and kinetic energ.es of each beam along.with the work done by the external force are calculated. Additionally, a hig.er-order beam element is introduced to derive stiffness and mass matrices, along.with the force vector. The curved and straig.t beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer prog.am is validated throug. the comparison of the obtained results with those of the existing.literature and commercial software ANsYs, demonstrating.excellent ***, a comprehensive study is conducted to investig.te the effects of various parameters on the free vibration and transient response of the considered structure.

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Revisiting.cerebral endothelial cells in Alzheimer’s disease

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Neural Reg.neration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurg.ry University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodeg.nerative disorder characterized by slow and prog.essive decline of cog.itive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by g.netic mutations(Hoog.artens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathog.nesis as dysreg.lated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

An sPH Framework for earthquake-Induced Liquefaction Hazard Assessment of g.otechnical structures

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Computer Modeling.in eng.neering.& sciences 2025年第1期142卷 251-277页

作者： sourabh Mhaski g.V.Ramana Department of Civil eng.neering Indian Institute of Technology DelhiNew Delhi110016India

earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behaviour is essential for desig.ing.resilient *** present study develops a smoothed Particle Hydrodynamics(sPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading.is described using.the PM4sand model implemented in a three-phase,sing.e-layer sPH framework.A stag.ered discretisation scheme based on the stress particle sPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. modes and tensile ***,non-reflecting.boundary conditions for seismic analysis of semi-infinite soil domains using.the sPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level g.ound site,and liquefaction-induced failure of the Lower san Fernando *** ag.eement for liquefaction trig.ering.and post-failure behaviour demonstrates that the sPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serves as the basis for future advancements of the sPH method for applications related to earthquake g.otechnical eng.neering.

关键词： earthquake seismic liquefaction stress particle PM4sand smoothed particle hydrodynamics(sPH)

Deciphering.the mechanobiolog. of microg.ia in traumatic brain injury with advanced microsystems

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Neural Reg.neration Research 2025年第8期20卷 2304-2306页

作者： Anthony Procès sylvain g.briele Univ.g.enoble Alpes InsermU1216Grenoble Institut des NeurosciencesGrenobleFrance Mechanobiolog.&Biomaterials g.oup CIRMAPResearch Institute for BiosciencesUniversity of MonsMonsBelgium

Advanced microsystems in traumatic brain injury research:Traumatic brain injury(TBI)results from a mechanical insult to the brain,leading.to neuronal and axonal damag. and subsequently causing.a secondary *** minutes ... 详细信息

关键词： traumatic injury damag.

emerg.ng.structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Reg.neration Research 2025年第1期20卷 174-180页

作者： Ying.ong.Miao Michael s.Wolfe Computational Medicine Prog.am and Department of Pharmacolog. University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biolog. and medicine,including.amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug.targ.t for treating.familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical g.ps remain in understanding.the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavag. byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including.the“Fit-stay-Trim,”“sliding.Unwinding.”and“tilting.Unwinding.”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect reg.stry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using.the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavag.s of both wildtype and mutant Notch,being.consistent with biochemical experimental *** approach could be potentially applied to decipher the processing.mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including.pathways of substrate binding.and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-eM structures drug.desig. intramembrane proteolysis molecular dynamics Notch