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Optimal Control of Service Rates of Discrete-Time(s,Q)Queuei.g.inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.iniya B.Sivakumar g.Arivarignan 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 queuei.g.inventory system with finite *** customers arrive accordi.g.to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arrivi.g.new customers are considered to be *** customers are served one by one accordi.g.to FCFS rule and each customers request random number of *** inventory is replenished accordi.g.to a(s,Q)inventory policy with geometric 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 waiti.g.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 programmi.g.method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

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

The great 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.Wignall David P.g.Bond School of Earth & Environment University of Leeds School of Environmental Sciences University of Hull

The marine losses duri.g.the Permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental change with eukaryotic algae bei.g.replaced by nitrogen-fixi.g.bacteria, green-sulphur bacteria, sulphate-reduci.g.bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddli.g.the Permo-Triassic boundary. Many of the losses occur at the beginni.g.and end of this interval painti.g.a picture of a two-phase extinction. improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timi.g.shows regional variability. Decreased ocean ventilation coincides with rapidly risi.g.temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicti.g.support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warmi.g. ocean stagnation and acidification. Volcanic winter episodes stemmi.g.from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(i.g.evidence for rapid warmi.g.duri.g.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

improved Dwarf Mongoose Optimization Algorithm for Feature Selection:Application in Software Fault Prediction Datasets

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Journal of Bionic Engineering 2024年第4期21卷 2000-2033页

作者： Abdelaziz i.Hammouri Mohammed A.Awadallah Malik ShBraik Mohammed Azmi Al-Betar Majdi Beseiso Department of Computer Science Al-Balqa Applied UniversityAl-Salt19117Jordan Department of Scientific Research and graduate Studies University of Prince Mugrin42241MedinaSaudi Arabia Department of Computer Science Al-Aqsa UniversityGaza4051Palestine Artificial intelligence Research Center(AiRC) Ajman UniversityAjmanUnited Arab Emirates Department of information Technology Al-Huson University CollegeAl-Balqa Applied UniversityAl-HusonIrbid21110Jordan

Feature selection(FS)plays a crucial role in pre-processi.g.machine learni.g.datasets,as it eliminates redundant features to improve classification accuracy and reduce computational *** paper presents an enhanced approach to FS for software fault prediction,specifically by enhanci.g.the binary dwarf mongoose optimization(BDMO)algorithm with a crossover mechanism and a modified positioni.g.updati.g.*** proposed approach,termed iBDMOcr,aims to fortify exploration capability,promote population diversity,and lastly improve the wrapper-based FS process for software fault prediction *** gained superb performance compared to other well-esteemed optimization methods across 17 benchmark *** ranked first in 11 out of 17 datasets in terms of average classification ***,iBDMOcr outperformed other methods in terms of average fitness values and number of selected features across all *** findi.g. demonstrate the effectiveness of iBDMOcr in addressi.g.FS problems in software fault prediction,leadi.g.to more accurate and efficient models.

关键词： Dwarf mongoose optimization algorithm Optimization Feature selection Classification

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

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Cellular & Molecular immunology 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 Biology 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 circulati.g.marginati.g.and tissue-infiltrati.g.neutrophils belong to the same homogeneous population and are capable of switchi.g.between these *** research has stagnated since the early 1980s,maintaini.g.a narrow and simplistic view of their capabilities.

关键词： narrow infiltrating differentiated

Selection of shaped charges parameters for produci.g.aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： Vladimir i.Kolpakov Sergey V.Fedorov Ekaterina P.Vinogradova irina A.Bolotina Bauman Moscow State Technical University Moscow 105005Russia

Testi.g.rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out usi.g.shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeli.g.of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics usi.g.three different computi.g.codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. it is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently slopi.g.segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-formi.g.part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation

The current status and future development of high-temperature conventional superconductivity

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National Science Review 2024年第07期 18-20页

作者： Mikhail i.Eremets High Pressure Chemistry and Physics group Max-Planck-Institut für Chemie

This survey highlights key advancements in high-temperature superconductivity in hydrogen-rich materials, emphasizi.g.the robust evidence and reproducibility of superconductivity under challengi.g.experimental conditions of megabar pressures. in the near future, achievi.g.room-temperature superconductivity is highly probable, and the field is expected to transition towards near-ambient-pressure superconductivity.

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Prompt neutron emission in ^(250)No spontaneous fission associated with ground and isomeric state decays

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Chinese Physics C 2024年第6期48卷 112-117页

作者： R.S.Mukhin A.V.isaev A.V.Andreev M.L.Chelnokov V.i.Chepigin H.M.Devaraja i.N.izosimov A.A.Kuznetsova O.N.Malyshev A.g.Popeko Yu.A.Popov A.Rahmatinejad B.Sailaubekov T.M.Shneidman E.A.Sokol A.i.Svirikhin M.S.Tezekbayeva M.A.Bychkov A.V.Yeremin O.Dorvaux B.gall K.Kessaci K.Hauschild A.Lopez-Martens Joint institute for Nuclear Research Dubna141980Russia Dubna State University Dubna141982Russia institute of Nuclear Physics Almaty050032Kazakhstan L.N.gumilyov Eurasian National University Astana010008Kazakhstan Kazan Federal University Kazan420008Russia Universitéde Strasbourg CNRSStrasbourg67000France iJCLab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)Pb(^(48)Ca,2n)^(250)No was used to study two activities of^(250)No with distinct half-lives.A total of 1357 events were observed in the SFiNx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)No was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and K-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide

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

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Neural Regeneration Research 2024年第2期19卷 390-392页

作者： Celso S.g.Catumbela Rodrigo Morales Department of Neurology McGovern Medical SchoolThe University of Texas Health Science Center at HoustonHoustonTXUSA Centro integrativo de Biologia y Quimica Aplicada(CiBQA) Universidad Bernardo O’HigginsSantiagoChile

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

关键词： amyloid diseases Aβ

Beneficial use of mussel shell as a bioadditive for TPU green composites by the valorization of an aqueous waste

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Waste Disposal and Sustainable Energy 2024年第1期6卷 123-137页

作者： SedefŞişmanoğlu Yasin Kanbur Carmen-Mihaela Popescu Diana Kindzera Ümit Tayfun Department of Chemistry Karabuk University78050KarabukTurkey Petru Poni institute of Macromolecular Chemistry of the Romanian Academy 700487IasiRomania Department of Chemical Engineering Lviv Polytechnic National UniversityLviv79013Ukraine Department of Basic Sciences Bartin University74110BartinTurkey

Scientific studies have focused on environmentally friendly solutions as effective as the reuse of crop products owi.g.to plastic-waste problems in recent *** issue is the main drivi.g.force for upcomi.g.academic research attempts in waste valorization-related ***,we integrated an aqua-waste,mussel shell(MS),as a bioadditive form into green thermoplastic polyurethane(TPU)green *** of the MS surface was performed to achieve strong adhesion between composite *** surface functionalities of MS powders were evaluated via infrared spectroscopy and scanni.g.electron microscopy(SEM)*** samples were prepared by melt-compoundi.g.followed by injection moldi.g.*** was confirmed by morphological analysis that relatively better adhesion between the phases was achieved for composites involvi.g.surface-modified MS compared to unmodified *** strength and Young’s modulus of surface-modified MS-filled composites were found to be higher than those of unmodified MS,whereas the elongation at break shifted to lower values with MS *** shore hardness of TPU was remarkably improved after bei.g.incorporated with silane-treated MS(AS-MS).Stearic acid-treated MS(ST-MS)additions resulted in an enhancement in the thermal stability of the ***-mechanical analysis showed that the storage moduli of composites were higher than those of unfilled ***-MS additions led to an increase in the characteristic glass transition temperature of *** flow index(MFi)of neat TPU was highly improved after MS loadi.g.regardless of modification *** to the wear test,surface modification of MS displayed a positive effect on the wear resistance of *** the water absorption data of the composites were evaluated,the TPU/AS-MS composite yielded the lowest water *** silane layer on MS inclusion promoted water repellency of composites due to the hydrophobicity of *** results of the biodegradation

关键词： Aqua-waste Polyurethane Mussel shell green composites Sustainability Waste valorization