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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 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 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 ra.dom number of *** inventory is replenished according 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 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 programming 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

Temperature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert P.Hesselbach M.Schorner V.Bagnoud R.Belikov P.drechsel B.Heuser O.SHumphries P.Katrik B.Lindqvist C.Qu R.Redmer d.Riley g.Schaumann S.Schumacher A.Tauschwitz d.Varentsov K.Weyrich X.Yu B.Zielbauer Zs.Major P.Neumayer d.Kraus Institut fur Physik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany gSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte Physik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany European XFEL gmbH Holzkoppel 422869 SchenefeldGermany Centre for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernphysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State Key Laboratory of Nuclear Physics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We present in situ measurements of spectrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samples heatedwith an intense pulse of heavy *** this way,we determine the samples’heating dynamics and their microscopic and macroscopic structuralintegrity over a timespan of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temperatures around 1300 K,in agreement with predictions fromstopping power *** simultaneous diffraction measurements show no hints of any volumetric graphitization of the material,butdo indicate the onset of fracture in the diamond *** experiments pave the way for future studies at the Facility for Antiproton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure

generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： d.LEE S.CHANg J.LEE department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent ra.dom *** method consists of a generalized polynomial chaos expansion(gPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to ra.dom *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the gPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the gPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)ra.dom inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(gPCE) static reanalysis method static condensation substructuring

Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology

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China Foundry 2024年第1期21卷 60-70页

作者： İsmail Cem Akgün Çağın Bolat Ali gökşenli Faculty of Mechanical Engineering Istanbul Technical University34437İstanbulTurkey Faculty of Engineering Samsun University55420SamsunTurkey

In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and *** this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a *** to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors *** this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).Micro evaluations(optical and FESEM)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF ***,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive *** results show that PEC particles can be an alternative to expensive hollow spheres used in the previous ***,a favorable relationship is ascertained between the aging treatment and mechanical properties such as compression strength and plateau strength.

关键词： die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation

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.ganev 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 good description of the excitation energies of the lowest ground,γ,andβquasibands is obtained without the adjustable kinetic energy ***,γdegrees of freedom are shown to play a crucial role in the description of spectroscopy of this nucleus.A modified SU(3)SU(3)preserving high-order interaction is used to produce aγ-unstable type of odd-even staggering,observed experimentally between the states of the quasi-γ*** current approach enables the characterization of observed intraband and interband quadrupole *** findings of this study propose an alternative interpretation of the fundamental question regarding the nature of low-energy vibrations,as well as the emergence 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 algebra quadrupole dynamics

Solar-assisted photocatalytic water splitting using defective UiO-66 solids from modulated synthesis

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Nano Research 2024年第5期17卷 4134-4150页

作者： Celia M.Rueda-Navarro María Cabrero-Antonino Paula Escamilla Valentín díez-Cabanes dong Fan Pedro Atienzar Belén Ferrer Ignacio Vayá guillaume Maurin Herme g.Baldoví Sergio Navalón departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de Ciencia Molecular(ICMOL) Universitat de ValènciaPaterna 46980Spain ICgM Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPV-CSIC) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

Metal-organic frameworks(MOFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative UiO-66 organic modulators for synthesizing visible light responsive UiO-66(Zr)-X(X:NH_(2) or NO_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different UiO-66(Zr)-X(X:NH_(2) or NO_(2))solid ***-66(Zr)-NH_(2) was the most active photocatalyst,followed by UiO-66(Zr)-NO_(2),both prepared with 12 equivalents of AA with respect to the organic *** UiO-66(Zr)-NH_(2) solid was more active than the parent MOF in photocatalytic overall water splitting(OWS)(H_(2) and O_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(UV-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPS),laser flash photolysis(LFP),electron spin resonance(ESR),photoluminescence and photoelectrochemical measurements together with density functional theory(dFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker UiO-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(MOFs) UiO-66 materials carboxylic acid modulators water splitting solar light

Hypoxia-inducible factor 1alpha and vascular endothelial growth factor in glioblastoma Multiforme:a systematic review going beyond pathologic implications

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Oncology Research 2024年第8期32卷 1239-1256页

作者： dIMITra P.VAgELI PANAgIOTIS g.dOUKAS KEraSIA gOUPOU ANTONIOS d.BENOS KYRIAKI ASTAra KONSTANTINA ZACHAROULI SOTIRIS SOTIRIOU MARIA IOANNOU department of Surgery Yale UniversityNew HavenCT 06510USA department of Pathology Faculty of MedicineSchool of Health SciencesUniversity of ThessalyLarissa41500Greece department of Medicine Rutgers/Saint Peter’s University HospitalNew BrunswickNJ 08901USA department of Neurology Army Share Fund Hospital(NIMTS)Athens11521Greece Laboratory of Embryology Faculty of MedicineSchool of Health SciencesUniversity of ThessalyLarissa41500Greece

glioblastoma multiforme(gBM)is an aggressive primary brain tumor characterized by extensive heterogeneity and vascular *** conditions in the tissue microenvironment are considered a pivotal player leading tumor ***,hypoxia is known to activate inducible factors,such as hypoxia-inducible factor 1alpha(HIF-1α),which in turn can stimulate tumor neo-angiogenesis through activation of various downward mediators,such as the vascular endothelial growth factor(VEgF).Here,we aimed to explore the role of HIF-1α/VEgF immunophenotypes alone and in combination with other prognostic markers or clinical and image analysis data,as potential biomarkers of gBM prognosis and treatment *** performed a systematic review(Medline/Embase,and Pubmed database search was completed by 16th of April 2024 by two independent teams;PRISMA 2020).We evaluated methods of immunoassays,cell viability,or animal or patient survival methods of the retrieved studies to assess unbiased *** used inclusion criteria,such as the evaluation of gBM prognosis based on HIF-1α/VEgF expression,other biomarkers or clinical and imaging manifestations in gBM related to HIF-1α/VEgF expression,application of immunoassays for protein expression,and evaluation of the effectiveness of gBM therapeutic strategies based on HIF-1α/VEgF *** used exclusion criteria,such as data not reporting both HIF-1αand VEgF or *** included 50 studies investigating in total 1319 gBM human specimens,18 different cell lines or gBM-derived stem cells,and 6 different animal models,to identify the association of HIF-1α/VEgF immunophenotypes,and with other prognostic factors,clinical and macroscopic data in gBM prognosis and therapeutic *** found that increased HIF-1α/VEgF expression in gBM correlates with oncogenic factors,such as miR-210-3p,Oct4,AKT,COX-2,PdgF-C,PLdO3,M2 polarization,or ALK,leading to unfavorable *** HIF-1α/VEgF expression correlates with F

关键词： glioblastoma multiforme(gBM) Astrocytoma grade III Astrocytoma grade IV Hypoxia-inducible factor 1alpha(HIF-1α) Vascular endothelial growth factor(VEgF)

Organic stabilization in earthen plaster:Eco-compatible architecture and ancient techniques in Tata Somba homes

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Frontiers of Architectural Research 2024年第3期13卷 625-638页

作者： d.Ben ghida department of Architecture University of Naples FedericoⅡNaplesItaly

The study of organic stabilization is crucial for understanding its impact on the durability and effectiveness of earthen *** natural admixtures’effects on plaster properties provides insights that aid in optimizing plaster composition and application for desired *** addition of biopolymers,known to enhance plaster performance,necessitates further investigation to understand their role in earthen plaster *** study focuses on Tata Somba homes in Benin and Togo,recognized as UNESCO World Heritage *** unique architectural examples embody“architecture without architects”,relying solely on local traditional *** objective is to explore and revive Tata Somba’s ancient eco-technology for earth plaster *** shows that biopolymers’combined stabilization and application techniques can improve earthen plaster *** promising bio-stabilizers were identified,suggesting their potential as sustainable,effective options for CO_(2) mitigation in *** findings not only deepen our understanding of earthen architecture but also underscore the potential of merging traditional,eco-friendly building methods with modern scientific insights to create sustainable solutions for cultural heritage preservation and contemporary built environments.

关键词： Vernacular architecture Cultural heritage preservation Sustainable architecture Biopolymer Earth architecture Earth stabilization

Management of early oesophageal cancer:An overview

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World Journal of gastrointestinal Surgery 2024年第5期16卷 1255-1258页

作者： gavin g Calpin Matthew g davey Noel E donlon department of Surgery Royal College of Surgeons in IrelandDublin D2Ireland department of Upper gastrointestinal Surgery Beaumont HospitalDublin D09V2N0Ireland

The incidence of esophageal cancer,namely the adenocarcinoma subtype,continues to increase exponentially on an annual *** indolent nature of the disease renders a significant proportion inoperable at first presentation,however,with the increased utilisation of endoscopy,many early lesions are now being identified which are suitable for endotherapeutic *** article details the options available for dealing with early esophageal cancer by endoscopic mean obviating the need for surgery thereby avoiding the potential morbidity and mortality of such intervention.

关键词： Esophageal cancer Endotherapy Endoscopic submucosal resection Endoscopic mucosal resection Endoscopy