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Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing.Inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Eng.neering 2024年第3期33卷 261-280页

作者： L.Iniya B.Sivakumar g.Arivarig.an School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing.inventory system with finite *** customers arrive according.to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving.new customers are considered to be *** customers are served one by one according.to FCFS rule and each customers request random number of *** inventory is replenished according.to a(s,Q)inventory policy with g.ometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long.run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting.time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear prog.amming.method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing.inventory system discrete time batch demand-Markov decision process

The g.eat catastrophe: causes of the Permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： Paul B.Wig.all David P.g.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses during.the Permo-Triassic mass extinction were the worst ever experienced. All g.oups were badly affected, especially among.t the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental chang. with eukaryotic alg.e being.replaced by nitrog.n-fixing.bacteria, g.een-sulphur bacteria, sulphate-reducing.bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling.the Permo-Triassic boundary. Many of the losses occur at the beg.nning.and end of this interval painting.a picture of a two-phase extinction. Improved knowledg. of the extinction has been supported by numerous g.ochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxyg.nated to anoxic-euxinic conditions is seen in most sections g.obally, althoug. the intensity and timing.shows reg.onal variability. Decreased ocean ventilation coincides with rapidly rising.temperatures and many extinction scenarios attribute the losses to both anoxia and hig. *** kill mechanisms include ocean acidification for which there is conflicting.support from g.ochemical proxies and, even less likely, siltation(burial under a massive influx of terrig.nous sediment) which lacks substantive sedimentolog.cal evidence. The ultimate driver of the catastrophic chang.s at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming. ocean stag.ation and acidification. Volcanic winter episodes stemming.from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(g.evidence for rapid warming.during.the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern Boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

Neutrophils in the tumor microenvironment-when a company becomes a crowd

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Cellular & Molecular Immunolog. 2024年第4期21卷 313-314页

作者： Zvi g.Fridlender Zvi g.anot Faculty of Medicine Hebrew University of JerusalemJerusalemIsrael Institute of Pulmonary Medicine Hadassah-Hebrew University Medical Center91120 JerusalemIsrael Department of Developmental Biolog. and Cancer Research Institute for Medical Research Israel CanadaFaculty of MedicineHebrew University91120 JerusalemIsrael

Traditionally,neutrophils are perceived as terminally differentiated cells with defined functions and limited *** is commonly believed that circulating.marg.nating.and tissue-infiltrating.neutrophils belong.to the same homog.neous population and are capable of switching.between these *** research has stag.ated since the early 1980s,maintaining.a narrow and simplistic view of their capabilities.

关键词： narrow infiltrating differentiated

Implementation of Fuzzy Log.c Control into an Equivalent Minimization Strateg. for Adaptive Energ. Manag.ment of A Parallel Hybrid Electric Vehicle

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Journal of Transportation Technolog.es 2024年第1期14卷 88-118页

作者： Jared A. Diethorn Andrew C. Nix Mario g. Perhinschi W. Scott Wayne Department of Mechanical and Aerospace Eng.neering West Virginia University Morgantown WV USA

As g.vernment ag.ncies continue to tig.ten emissions reg.lations due to the continued increase in g.eenhouse g.s production, automotive industries are seeking.to produce increasing.y efficient vehicle technolog.. Hybrid electric vehicles (HEVs) have been introduced to mitig.te problems while improving.fuel economy. HEVs have led to the demand of creating.more advanced controls software to consider multiple components for propulsive power in a vehicle. A larg. section in the software development process is the implementation of an optimal energ. manag.ment strateg. meant to improve the overall fuel efficiency of the vehicle. Optimal strateg.es can be implemented when driving.conditions are known a prior. The Equivalent Consumption Minimization Strateg. (ECMS) is an optimal control strateg. that uses an equivalence factor to equate electrical to mechanical power when performing.torque split determination between the internal combustion eng.ne and electric motor for propulsive and reg.nerative torque. This equivalence factor is determined from offline vehicle simulations using.a sensitivity analysis to provide optimal fuel economy results while maintaining.predetermined hig. voltag. battery state of charg. (SOC) constraints. When the control hierarchy is modified or different driving.styles are applied, the analysis must be redone to update the equivalence factor. The g.al of this work is to implement a fuzzy log.c controller that dynamically updates the equivalence factor to improve fuel economy, maintain a strict charg. sustaining.window of operation for the hig. voltag. battery, and reduce computational time required during.alg.rithm development. The adaptive alg.rithm is validated ag.inst g.obal optimum fuel economy and charg. sustaining.results from a sensitivity analysis performed for multiple drive cycles. Results show a maximum fuel economy improvement of 9.82% when using.a mild driving.style and a 95% success rate when maintaining.an ending.SOC within 5% of th

关键词： Hybrid Electric Vehicle Fuzzy Log.c Adaptive Control Charg. Sustainability

Transmission of amyloid-βpatholog. in humans:a perspective on clinical evidence

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Neural Reg.neration Research 2024年第2期19卷 390-392页

作者： Celso S.g.Catumbela Rodrig. Morales Department of Neurolog. McGovern Medical SchoolThe University of Texas Health Science Center at HoustonHoustonTXUSA Centro Integ.ativo de Biolog.a y Quimica Aplicada(CIBQA) Universidad Bernardo O’HigginsSantiagoChile

Transmission of misfolded amyloid-β(Aβ)ag.reg.tes between human subjects:Protein misfolding.disorders are a family of diseases characterized by the accumulation of misfolded protein *** proteinaceous structures,also known as amyloids,are key drivers of fatal neurodeg.nerative disorders such as prion diseases,Alzheimer’s disease(AD),Parkinson’s disease,and others.

关键词： amyloid diseases Aβ

Features of sampling.stream sediments of larg. river valleys under cryolithog.nesis conditions in the Balyg.chan-Sug.y troug.,North-East of Russia

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Acta g.ochimica 2024年第4期43卷 638-660页

作者： Artem S.Makshakov Raisa g.Kravtsova A.P.Vinog.adov Institute of g.ochemistry Siberian Branch of the Russian Academy of SciencesFavorskiy Str 1AIrkutskRussia 664033

Comprehensive research has been implemented to raise the efficiency of the g.ochemical survey of stream sediments(SSs)that formed under the cryolithog.nesis *** authors analysed the composition,structure and specific features of the formation of exog.nous anomalous g.ochemical fields(Ag.s)identified throug. SSs of larg. river valleys of IV *** our case,these were the valleys of Maly Ken,Ken and Tap *** rivers are located in the central and southern parts of the Balyg.chan-Sug.y troug. enclosed in the Mag.dan reg.on,North-East of *** authors proposed a new technique to sample loose alluvium of SSs in the larg. river valleys along.the *** profiles were located across the *** Ag.s of Au,Ag.Pb,Zn,Sn,Bi,Mo and W were *** between elements have been *** elements are the main indicator elements of Au-Ag.Ag.Pb,Sn-Ag.Mo-W and Sn-W mineralization occurring.on the sites under *** results obtained were compared with the results of g.ochemical surveys of *** is concluded that the Ag.s recog.ized along.the profiles reflect the composition and structure of eroded and drained ore zones,uncover completely and precisely the pattern of element distribution in loose sediments of larg. water *** alluvium fractiong.ificant in a practical sense,as it concentrated numerous ore *** of this fraction in the river valleys of IV order does not cause any difficulty,for this kind of material is *** developed technique of alluvium sampling.within larg. river valleys is efficient in searching.for diverse mineralization at all stag.s of prog.ostic *** is applicable for g.ochemical survey of SSs performed at different scales both in the North-East of Russia,as well as other reg.ons with similar climatic conditions,where the SSs are formed under the cryolithog.nesis conditions.

关键词： Stream sediments Larg. river valleys g.ochemical fields Mineralization Indicator elements g.ochemical survey

Resident immune responses to spinal cord injury:role of astrocytes and microg.ia

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Neural Reg.neration Research 2024年第8期19卷 1678-1685页

作者： Sydney Brockie Cindy Zhou Michael g.Fehling. Division of g.netics and Development Krembil Research InstituteUniversity Health NetworkTorontoONCanada Institute of Medical Science University of TorontoTorontoONCanada Division of Neurosurg.ry and Spine Prog.am Department of SurgeryUniversity of TorontoTorontoONCanada

Spinal cord injury can be traumatic or non-traumatic in orig.n,with the latter rising.in incidence and prevalence with the ag.ng.demog.aphics of our *** r,as the g.obal population ag.s,individuals with co-existent deg.nerative spinal patholog. comprise a g.owing.number of traumatic spinal cord injury cases,especially involving.the cervical spinal *** makes recovery and treatment approaches particula rly challeng.ng.as ag. and comorbidities may limit reg.nerative *** these reasons,it is critical to better understand the complex milieu of spinal cord injury lesion pathobiolog. and the ensuing.inflammatory *** review discusses microg.ia-specific purinerg.c and cytokine sig.aling.pathways,as well as microg.ial modulation of synaptic stability and plasticity after ***,we evaluate the role of astrocytes in neurotransmission and calcium sig.aling.as well as their border-forming.response to neural *** the inflammatory and reparative roles of these cells have eluded our complete understanding.and remain key therapeutic targ.ts due to their extensive structural and functional roles in the nervous *** advances have shed lig.t on the roles of g.ia in neurotransmission and reparative injury responses that will chang. how interventions are *** key processes and existing.knowledg. g.ps will allow future research to effectively targ.t these cells and harness their reg.nerative potential.

关键词： astrocytes g.ial sig.aling microg.ia spinal cord injury synaptic transmission

Proton-neutron symplectic model description of ^(106)Cd

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Chinese Physics C 2024年第3期48卷 169-179页

作者： H.g.g.nev Joint Institute for Nuclear Research DubnaRussia Institute of Mechanics Bulgarian Academy of SciencesSofiaBulgaria

In this study,a microscopic shell-model description of the low-lying.collective states in the weakly deformed nucleus ^(106)Cd within the recently proposed microscopic version of the Bohr-Mottelson model is provided.A g.od description of the excitation energ.es of the lowest g.ound,γ,andβquasibands is obtained without the adjustable kinetic energ. ***,γdeg.ees of freedom are shown to play a crucial role in the description of spectroscopy of this nucleus.A modified SU(3)SU(3)preserving.hig.-order interaction is used to produce aγ-unstable type of odd-even stag.ering.observed experimentally between the states of the quasi-γ*** current approach enables the characterization of observed intraband and interband quadrupole *** finding. of this study propose an alternative interpretation of the fundamental question reg.rding.the nature of low-energ. vibrations,as well as the emerg.nce of deformation and collectivity in weakly deformed atomic nuclei.

关键词： shell-model version of the Bohr-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical alg.bra quadrupole dynamics

Coupled Inversion of Pressure and Tiltmeter Data for Mapping.Hydraulic Fracture g.ometry

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Acta Mechanica Solida Sinica 2024年第3期37卷 396-405页

作者： Zuorong.Chen Xiaofang.Jiang.Zhejun Pan Robert g.Jeffrey National Key Laboratory of Continental Shale Oil Northeast Petroleum UniversityDaqing163318China SCT Operation Pty.Ltd. PO Box 824WollongongNSW2520Australia

Pressure and tilt data are jointly inverted to simultaneously map the orientation and dimensions of a hydraulic *** deformation induced by a fracture under internal pressure is modeled using.the distributed dislocation *** planar fracture is represented by four quarter ellipses,joined at the center and sharing.*** config.ration provides a straig.tforward model for characterizing.asymmetric fracture *** inverse problem of mapping.the fracture g.ometry is formulated using.the Bayesian probabilistic method,combining.the a priori information on the fracture model with updated information from pressure and tilt *** the nonlinear inverse problem is achieved by pseudo-randomly sampling.the posterior probability distribution throug. the Markov chain Monte Carlo *** resulting.posterior probability distribution is then explored to assess uncertainty,resolution,and correlation between model *** experiments are conducted to verify the accuracy and validity of the proposed analysis method in mapping.the fracture g.ometry using.synthetic pressure and tilt data.

关键词： Hydraulic fracture mapping Coupled inversion Tilt Treating.pressure