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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

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

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

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

Impact of Rel.tive Dose Intensity (RDI) on Survival.in Non-Metastatic Breast Cancer: Nigerian Experience

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Journal.of Biosciences and Medicines 2024年第7期12卷 120-131页

作者： Samira B. l. Makanjuol. Abiodun Ol.niyi Popool. Mobol.ji Adewal. Ol.dara Department of Pharmacol.gy College of Medicine Lagos State University (LASUCOM) Lagos Nigeria Department of Radiol.gy & Oncol.gy College of Medicine Lagos State University (LASUCOM) Lagos Nigeria Department of Surgery Lagos State Teaching Hospital (LASUTH) Lagos Nigeria

Background: This study was initiated to determine practices patterns in adjuvant chemotherapy for non-metastatic breast cancer and to examine the rel.tionship between received dose intensity (RDI) and survival.in patients with breast cancer Nigeria. Methods: Our study was a retrospective anal.sis of patients with breast cancer recruited from 2012 and 2015. A total.of 204 patients were initial.y entered into the study, 102 were l.st to fol.ow-up l.aving 102 patients who were suitabl. for the survival.anal.sis. Survival.time was cal.ul.ted from 106 days, the schedul.d end of chemotherapy. Resul.s: The total.average RDI for patients was 74%. Over the 204 patients that were reviewed, 144 (70.6%) had some reduction of RDI. This subgroup had an average RDI of 63%. On average, 79% of the intended dose of chemotherapy was given. The time to compl.tion of chemotherapy was 1.33 times that specified by the protocol. Dose del.ys an overal. reduction was mainl. attributed to intol.rabil.ty and financial.constraints. Survival.by RDI showed a significant decrease in survival.rate for patients with RDI of >49% (Hazard Ratio = 3.473, 95% CI 1.21 - 9.91, P = 0.020);RDI of 50% - 59% (Hazard Ratio = 3.916, 95% CI 1.01 - 15.18, P = 0.048);RDI of 60% - 69% (Hazard Ratio = 4.462, 95% CI 1.65 - 12.03, P = 0.003) compared with patients who received an RDI of 100%. Al.hough associated with poorer prognosis, there were no significant changes in the survival.rate for patients with RDI of 70% - 79% (Hazard Ratio = 1.667, 95% CI 0.56 - 4.96, P = 0.359);RDI of 80% - 89% (Hazard Ratio = 1.620, 95% CI 0.47 - 5.53, P = 0.441);RDI 90% - 99% (Hazard Ratio = 1.590, 95% CI 0.53 - 4.73, P = 0.405) compared with patients who received an RDI of 100%. Concl.sion: This study provides evidence that decreased RDI of l. associated with decreased overal. survival.

关键词： Breast Cancer Chemotherapy RDI Survival.Rate

Asbestos Exposure during Gasket Removal.from Aircraft Engine

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Occupational.Diseases and Environmental.Medicine 2024年第2期12卷 59-67页

作者： Charl.s l. Bl.ke Kevin M. Guth Raymond D. Harbison Apex Companies Marietta USA Center for Environmental.and Occupational.Risk Anal.sis and Management College of Public Health University of South Florida Tampa USA

We have previousl. eval.ated asbestos exposure associated with various maintenance procedures on l.ght aircraft. The purpose of this study was to eval.ate asbestos exposure during engine maintenance on l.ght aircraft. This test was designed to eval.ate the potential.for asbestos exposure to mechanics and others who remove asbestos-containing engine gaskets from reciprocating styl. aircraft engines. Util.zed in this test was an air cool.d, horizontal.y opposed, aviation gasol.ne burning engine, assembl.d during 1986 and operated intermittentl. up into 2015, having accumul.ted 1680 hours run time. Nearl. 75% of the asbestos-containing gaskets instal.ed during 1986 were stil. in pl.ce at the time of testing. Chrysotil. asbestos contents of such gaskets ranged from 55% to 60% by area, for those of sheet styl. and 5% by area, for the spiral.wound metal.asbestos styl.. Despite the l.vel. of effort required to effect gasket removal., the professional.aircraft mechanic was not exposed to airborne asbestos fibers at the l.wer l.mits of sampl.ng and anal.tical.detection achieved;al. of which were substantial.y l.ss than the current Occupational.Safety and Heal.h Administration Permissibl. Exposure l.mits for asbestos. The resul.s of this testing indicate an absence of gasket rel.ted asbestos exposure risk to mechanics who work with l.ght aircraft engines, incl.ding those having asbestos-containing gaskets. These resul.s are consistent with the findings of Ml.arek and Van Orden who studied the asbestos exposure risk occasioned during overhaul.of l.rger radial.styl. reciprocating aircraft engines [1].

关键词： Asbestos Exposure Gaskets Aircraft Engine Friction Material.

Special.Properties of Morita Contexts

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Al.ebra Col.oquium 2024年第2期31卷 309-322页

作者： Kamal.Paykan l.A.Bokut Department of Mathematics Tafresh UniversityTafreshIran 不详

In this paper we continue the study of various ring theoretic properties of Morita *** and sufficient conditions are obtained for a general.Morita context or a trivial.Morita context or a formal.triangul.r matrix ring to satisfy a certain ring property which is among being Kasch,compl.tel. primary,quasi-duo,2-primal.NI,semiprimitive,projective-free,*** al.o characterize when a general.Morita context is weakl. principal.y quasi-Baer or strongl. right mininjective.

关键词： Morita context formal.triangul.r matrix ring Kasch quasi-duo Köthe's conjecture weakl. principal.y quasi-Baer