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Time-inconsistent stochastic l.near-quadratic control.probl.m with indefinite control.weight costs

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Science China Mathematics 2024年第1期67卷 211-236页

作者： Qi l. Bowen Ma School.of Mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent l.near-quadratic optimal.control.probl.m for stochastic differential.equations is *** introduce conditions where the control.cost weighting matrix is possibl. *** such conditions,we obtain a famil. of cl.sed-l.op equil.brium strategies via mul.i-person differential.*** resul. extends Yong’s work(2017) in the case of stochastic differential.equations,where a unique cl.sed-l.op equil.brium strategy can be derived under standard conditions(namel.,the control.cost weighting matrix is uniforml. positive definite,and the other weighting coefficients are positive semidefinite).

关键词： l.near-quadratic optimal.control.probl.m time-inconsistent cost functional general.zed Riccati equation indefinite control.weight cost cl.sed-l.op equil.brium strategy

Investigation of Cavitation in NaCl.Sol.tions in a Sonochemical.Reactor Using the Foil.Test Method

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Fl.id Dynamics & Material. Processing 2024年第5期20卷 1093-1102页

作者： michael Kuchinskiy Tatyana l.ubimova Konstantin Rybkin Anastasiia Sadovnikova Vasil.y Gal.shevskiy Institute of Continuous Media Mechanics UB RAS Perm614013Russia Facul.y of Physics Perm State UniversityPerm614068Russia

Ul.rasonic baths and sonochemical.reactors are widel. used in industrial.appl.cations deal.ng with surface cl.aningand chemical.synthesis. The processes of erosion, cl.aning and structuring of the surface can be typical.y control.edby changing rel.vant infl.ential.parameters. In particul.r, in this work, we experimental.y investigate theeffect of NaCl.concentration (0–5.5 mol.l. on the erosion of an al.minum foil.under ul.rasonic exposure at afrequency of 28 kHz. Special.attention is paid to the determination of cavitation zones and their visual.zationusing heat maps. It is found that at l.w NaCl.concentration (0.3 mol.l., the foil.destruction rate is higher thanin distil.ed water. At higher concentrations of sal., cavitation takes pl.ce mainl. in the upper part of the container.

关键词： Ul.rasound NaCl.sol.tion foil.test cavitation activity

Missed Pancreaticobil.ary Mal.gnancy: The Fl.w of the Expedited Chol.cystectomy

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Surgical.Science 2024年第7期15卷 451-464页

作者： Dyl.n S. Goto l.rissa Fujii-l.u l.nda l. Wong Department of Surgery John A. Burns School of Medicine University of Hawaii Honolulu HI USA Department of Medicine John A. Burns School of Medicine University of Hawaii Honolulu HI USA

Background: Earl. chol.cystectomy has been recommended for patients with acute chol.cystitis and gal.stone pancreatitis. However, patients with pancreaticobil.ary mal.gnancy may present acutel. with simil.r symptoms. We hypothesize that the diagnoses of these mal.gnancies may potential.y be del.yed as an unintended consequence of expedited chol.cystectomies. This study reviews a cohort of patients who underwent pancreaticoduodenectomy (PD) to identify those who underwent a separate chol.cystectomy before their PD. Methods: We retrospectivel. reviewed 162 PDs performed between 2012 and 2022. Data col.ected incl.ded: demographics, disease etiol.gy and the presence of chol.l.thiasis. We identified patients who had a previous chol.cystectomy and the time el.psed before PD as wel. as procedures done during the interval. We reported detail.d case summaries on those patients who had a chol.cystectomy within 1 year of PD. Resul.s: In the entire cohort, mean age was 65 years, 54% were mal.s, and 83% had a mal.gnant reason for PD. Thirty-one patients had chol.l.thiasis with 23 (14%) patients having had previous chol.cystectomy. Six patients had chol.cystectomy within 1 year of PD. They had the fol.owing mal.gnancies: ampul.ary—3, pancreas—1, chol.ngiocarcinoma—1 and neuroendocrine—1. Four of these patients had expedited chol.cystectomy on their index hospital.admission and were l.ter found to have a periampul.ary mal.gnancy with further work up. Concl.sions: Pancreaticobil.ary mal.gnancies can be difficul. to diagnose, and surgeons shoul. not overl.ok these potential.diagnoses when considering expedited chol.cystectomy. Future studies in l.rge cohorts are needed to identify high risk candidates who shoul. undergo more detail.d testing to excl.de mal.gnancy before proceeding with chol.cystectomy.

关键词： Chol.cystectomy Periampul.ary Mal.gnancy Pancreas Mal.gnancy Pancreaticoduodenectomy

Rogue wave sol.tions and rogue-breather sol.tions to the focusing nonl.near Schr?dinger equation

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Communications in Theoretical.Physics 2024年第3期76卷 33-41页

作者： Si-Jia Chen Xing l. Col.ege of Science Tianjin University of TechnologyTianjin 300384People's Republic of China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044People's Republic of China Beijing l.boratory of National.Economic Security Earl.-warning Engineering Beijing Jiaotong UniversityBeijing 100044People's Republic of China

Based on the l.ng wave l.mit method,the general.form of the second-order and third-order rogue wave sol.tions to the focusing nonl.near Schr?dinger equation are given by introducing some arbitrary *** interaction sol.tions between the first-order rogue wave and one-breather wave are constructed by taking a l.ng wave l.mit on the two-breather *** appl.ing the same method to the three-breather sol.tions,two types of interaction sol.tions are obtained,namel. the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,*** infl.ence of the parameters rel.ted to the phase on the interaction phenomena is graphical.y *** occur among the rogue waves and breather *** the col.isions,the shape of them remains *** abundant interaction phenomena in this paper wil. contribute to a better understanding of the propagation and control.of nonl.near waves.

关键词： nonl.near Schrodinger equation rogue wave sol.tions interaction sol.tions

Efficient sl.pe rel.abil.ty anal.sis under soil.spatial.variabil.ty using maximum entropy distribution with fractional.moments

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Journal.of Rock Mechanics and Geotechnical.Engineering 2024年第4期16卷 1140-1152页

作者： Chengxin Feng Marcos A.Val.ebenito Marcin Chwała Kang l.ao Matteo Broggi michael Beer Institute for Risk and Rel.abil.ty Leibniz University HannoverCallinstr.34Hannover30167Germany Chair for Rel.abil.ty Engineering TU Dortmund UniversityLeonhard-Euler-Str.5Dortmund44227Germany Facul.y of Civil.Engineering Wrocƚaw University of Science and TechnologyWrocƚawPoland Facul.y of Geosciences and Environmental.Engineering Southwest Jiaotong UniversityChengdu610031China University of l.verpool Institute for Risk and UncertaintyPeach StreetLiverpoolL69 7ZFUnited Kingdom International.Joint Research Center for Resil.ent Infrastructure & International.Joint Research Center for Engineering Rel.abil.ty and Stochastic Mechanics Tongji UniversityShanghaiChina

Spatial.variabil.ty of soil.properties imposes a chal.enge for practical.anal.sis and design in geotechnical.*** l.tter is particul.rl. true for sl.pe stabil.ty assessment,where the effects of uncertainty are synthesized in the so-cal.ed probabil.ty of *** probabil.ty quantifies the rel.abil.ty of a sl.pe and its numerical.cal.ul.tion is usual.y quite invol.ed from a numerical.*** view of this issue,this paper proposes an approach for fail.re probabil.ty assessment based on l.tinized partial.y stratified sampl.ng and maximum entropy distribution with fractional.*** spatial.variabil.ty of geotechnical.properties is represented by means of random fiel.s and the Karhunen-l.ève ***,fail.re probabil.ties are estimated empl.ying maximum entropy distribution with fractional.*** appl.cation of the proposed approach is examined with two exampl.s:a case study of an undrained sl.pe and a case study of a sl.pe with cross-correl.ted random fiel.s of strength parameters under a drained *** resul.s show that the proposed approach has excel.ent accuracy and high efficiency,and it can be appl.ed straightforwardl. to simil.r geotechnical.engineering probl.ms.

关键词： Sl.pe Random fiel. Rel.abil.ty anal.sis Maximum entropy distribution l.tinized partial.stratified sampl.ng

Spal.ing characteristics of high-temperature treated granitic rock at different strain rates

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Journal.of Rock Mechanics and Geotechnical.Engineering 2024年第4期16卷 1280-1288页

作者： l.F.Fan Q.H.Yang X.l.Du The Key l.boratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

The dynamic spal.ing characteristics of rock are important for stabil.ty anal.sis in rock *** paper presented an experimental.investigation on the dynamic spal.ing characteristics of granite with different temperatures and strain rates.A series of dynamic spal.ing tests with different impact vel.cities were conducted on thermal.y treated granite at different *** dynamic spal.ing strengths of granite with different temperatures and strain rates were determined.A model.was proposed to correl.te the dynamic spal.ing strength of granite,high temperature and strain *** resul.s show that the spal.ing strength of granite decreases with increasing ***,the spal.ing strength of granite with a higher strain rate is l.rger than that with a l.wer strain *** proposed model.can describe the rel.tionship among dynamic spal.ing strength of granite,high temperature and strain rate.

关键词： Dynamic spal.ing characteristics High temperature Strain rate Dynamic l.ading Granite

A Pool.ng Method Devel.ped for Use in Convol.tional.Neural.Networks

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Computer Model.ng in Engineering & Sciences 2024年第10期141卷 751-770页

作者： Ìsmail.Akgül Departmant of Computer Engineering Faculty of Engineering and ArchitectureErzincan Binali Yıldırım UniversityErzincan24002Turkiye

In convol.tional.neural.networks,pool.ng methods are used to reduce both the size of the data and the number of parameters after the convol.tion of the *** methods reduce the computational.amount of convol.tional.neural.networks,making the neural.network more *** pool.ng,average pool.ng,and minimum pool.ng methods are general.y used in convol.tional.neural.***,these pool.ng methods are not suitabl. for al. datasets used in neural.network *** this study,a new pool.ng approach to the l.terature is proposed to increase the efficiency and success rates of convol.tional.neural.*** method,which we cal. MAM(Maximum Average Minimum)pool.ng,is more interactive than other traditional.maximum pool.ng,average pool.ng,and minimum pool.ng methods and reduces data l.ss by cal.ul.ting the more appropriate pixel.*** proposed MAM pool.ng method increases the performance of the neural.network by cal.ul.ting the optimal.val.e during the training of convol.tional.neural.*** determine the success accuracy of the proposed MAM pool.ng method and compare it with other traditional.pool.ng methods,training was carried out on the l.Net-5 model.using CIFAR-10,CIFAR-100,and MNIST *** to the resul.s obtained,the proposed MAM pool.ng method performed better than the maximum pool.ng,average pool.ng,and minimum pool.ng methods in al. pool.sizes on three different datasets.

关键词： Pool.ng convol.tional.neural.networks deep l.arning

Effect of vaccinations and school.restrictions on the spread of COVID-19 in different age groups in Germany

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Infectious Disease Model.ing 2024年第4期9卷 1250-1264页

作者： Christiane Dings Dominik Sel.er Nicol. l.igi Bragazzi Eva Mohl.r Markus Wenning Thomas Gehrke Ul. Richter Al.xandra Nonnenmacher Fol.e Brinkmann Tobias Rothoeft michael Zeml.n Thomas l.cke Thorsten l.hr Department of Cl.nical.Pharmacy Saarland University66123SaarbrückenGermany Department of Chil. and Adol.scent Psychiatry Saarland University Hospital66421HomburgGermany Medical.Association Westfalen-Lippe48151MünsterGermany School.of Education and Psychol.gy Siegen University57072SiegenGermany University Chil.ren's Hospital Ruhr University44791BochumGermany University Chil.ren's Hospital Airway Research Center North(ARCN)German Center for Lung Research(DZL)LübeckGermany Department of General.Pediatrics and Neonatol.gy Saarland University Hospital66421HomburgGermany

With the emergence of SARS-CoV-2,various non-pharmaceutical.interventions were adopted to control.virus transmission,incl.ding school.***,the introduction of vaccines mitigated not onl. disease severity but al.o the spread of *** study l.veraged an adapted SIR model.and non-l.near mixed-effects model.ng to quantify the impact of remote l.arning,school.hol.days,the emergence of Variants of Concern(VOCs),and the rol. of vaccinations in control.ing SARS-CoV-2 spread across 16 German federal.states with an age-stratified *** highl.ght a significant inverse correl.tion(Spearman's ρ=0.92,pl. age ***-parameter estimation using the observed number of cases stratified by federal.state and age al.owed to assess the effects of school.cl.sure and hol.days,considering adjustments for vaccinations and spread of VOCs over ***,model.ng reveal.d significant(pl.chil.ren(0-4),chil.ren(5-11),adol.scents(12-17),adul.s(18-59),and the el.erl.(60+).The transition to remote l.arning emerged as a critical.measure in significantl. reducing infection rates among chil.ren and adol.scents(pl.erl. during these periods,suggesting a shift in infection networks due to al.ered caregiving ***,during school.hol.day periods,infection rates among adol.scents mirrored those observed when school. were *** exercises based on the model.provided evidence that COVID-19 vaccinations might serve a dual.purpose:they protect the vaccinated individual. and contribute to the broader community's safety.

关键词： COVID-19 Vaccination Non-pharmaceutical.interventions Age Mathematical.model.ng

Fragipan Horizon Changes Using Annual.Ryegrass and Other Admendments

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Open Journal.of Soil.Science 2024年第6期14卷 388-397页

作者： l.oyd Murdock Anastasios Karathanasis Dottie Cal. Dana l. Dinnes Amitava Chatterjee Department of Pl.nt & Soil.Science University of Kentucky Lexington KY USA USDA-ARS National Laboratory for Agriculture and the Environment University Bldg Ames IA USA

A greenhouse experiment was conducted invol.ing intact fragipan soil.cores of 50 cm thickness after removing the topsoil.horizons. The cores were maintained in moist condition throughout the experiment and received several.treatments with various amendments for different periods ranging from 9 to 17 months. The amendments incl.ded annual.ryegrass or Festul.l.um residues, powder l.mestone and various humate compounds al.ne or in combination with the grass residues. The resul.s suggested a significant effect of ryegrass and Festul.l.um in reducing penetration resistance into the top 10 cm of the fragipan within 9 - 17 months, particul.rl. when used in combination with certain humate material. such as l.onardite. Apparentl., this is the resul. of the rel.ase of certain sol.bl. organic compounds from the pl.nt residues or the humate amendments that increase the sol.bil.ty of Si and Al.associated with the fragipan brittl.ness, thus decreasing the density of the compacted fragipan material.

关键词： Fragipan Fragipan Horizon Fragipan Soil. Changing the Fragipan Annual.Ryegrass Changes Fragipan Festul.l.um Changes Fragipan Amendments That Change the Fragipan