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Communications in Theoretical Physics 2024年第2期76卷 1-13页

作者： Yexuan Feng Zhonglong zhao School of Mathematics North University of ChinaTaiyuanShanxi 030051China

In this paper,we mainly focus on proving the existence of lump solutions to a generalized(3+1)-dimensional nonlinear differential ***’s bilinear method and a quadratic function method are employed to derive the lump solutions localized in the whole plane for a(3+1)-dimensional nonlinear differential *** examples of such a nonlinear equation are presented to investigate the exact expressions of the lump ***,the 3d plots and corresponding density plots of the solutions are given to show the space structures of the lump *** addition,the breath-wave solutions and several interaction solutions of the(3+1)-dimensional nonlinear differential equation are obtained and their dynamics are analyzed.

关键词： lump solutions generalized(3+1)-dimensional nonlinear differential equation Hirota's bilinear method quadratic function method interaction solutions

Universal method for designing periodic orbits by homotopy classes in the elliptic restricted three-body problem

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Astrodynamics 2024年第1期8卷 175-188页

作者： Yue Zheng Min zhao School of Electronic Engineering Xi’an Aeronautical InstituteXi’an710077China School of Aircraft Engineering Xi’an Aeronautical InstituteXi’an710077China School of Astronautics Northwestern Polytechnical UniversityXi’an710072China

The current methods for designing periodic orbits in the elliptic restricted three-body problem(ERTBP)have the disadvantages of targeting limited orbits and ergodic searches and considering only symmetric orbits.A universal method for designing periodic orbits is proposed in this ***,the homotopy classes of orbits are structured based on their topological ***,a dynamic model based on homotopy classes,ranging from the circular restricted three-body problem(CRTBP)to the ERTBP,can be built using the homotopy ***,a multi-and a single-period orbit were selected based on the resonance ***,the corresponding orbit in the ERTBP was computed by modifying the initial condition of the orbit in the *** method,without an ergodic search,can extend to any orbit,including an asymmetric orbit in the CRTBP,to the ERTBP model,and the two orbits are of the same homotopy *** of the Earth–Moon ERTBP are presented to verify the efficiency of this method.

关键词： periodic orbit elliptic restricted three-body problem(ERTBP) topology homotopy circular restricted three-body problem(CRTBP)

STRONG CONVERGENCE OF JUMP-ADAPTED IMPLICIT MILSTEIN METHOD FOR A CLASS OF NONLINEAR JUMP-DIFFUSION PROBLEMS

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Journal of Computational Mathematics 2024年第1期42卷 248-270页

作者： Xu Yang Weidong zhao School of Mathematics China University of Mining and TechnologyXuzhou 221116China School of Mathematics Shandong UniversityJinan 250100China

In this paper,we study the strong convergence of a jump-adapted implicit Milstein method for a class of jump-diffusion stochastic differential equations with non-globally Lipschitz drift *** with the regular methods,the jump-adapted methods can significantly reduce the complexity of higher order methods,which makes them easily implementable for scenario ***,due to the fact that jump-adapted time discretization is path dependent and the stepsize is not uniform,this makes the numerical analysis of jump-adapted methods much more involved,especially in the non-globally Lipschitz *** provide a rigorous strong convergence analysis of the considered jump-adapted implicit Milstein method by developing some novel analysis techniques and optimal rate with order one is also successfully *** experiments are carried out to verify the theoretical findings.

关键词： Jump-diffusion Jump-adapted implicit Milstein method Poisson jumps Strong convergence rate Non-Lipschitz coefficients

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胃癌血管侵犯的临床病理分析

中华消化外科杂志 2015年第3期14卷 207-211页

作者：余亮吕成余赵有财陈维袁爱华南京医科大学附属南京医院普通外科 210006 南京医科大学附属南京医院病理科 210006

目的探讨胃癌血管侵犯与患者临床病理因素及预后的关系，分析影响胃癌患者预后的相关因素。方法回顾性分析2007年1月至2010年12月南京医科大学附属南京医院收治的206例胃癌患者的临床病理资料。收集胃癌患者手术切除的肿瘤标本，采用免... 详细信息

目的探讨胃癌血管侵犯与患者临床病理因素及预后的关系，分析影响胃癌患者预后的相关因素。方法回顾性分析2007年1月至2010年12月南京医科大学附属南京医院收治的206例胃癌患者的临床病理资料。收集胃癌患者手术切除的肿瘤标本，采用免疫组织化学染色检测肿瘤标的本血管侵犯情况。采用门诊和电话方式进行随访，随访时间截至2014年3月。计数资料比较采用r检验。采用Kaplan-Meier法绘制生存曲线，Log-rank检验进行生存分析和单因素分析。采用COX模型逐步后退法进行多因素分析。结果206例患者中，血管侵犯率为27．67％（57／206）。胃癌患者的不同肿瘤分化程度、神经侵犯、T分期、N分期、TNM分期胃癌组织中血管侵犯率比较，差异有统计学意义（χ^2=14．396，9．569，15．579，43．453，30．732，P〈0．05）。188例患者获得术后随访，随访率为91．26％（188／206），随访时间为6．0～60．0个月，中位随访时间为34．0个月。188例获得随访患者中，血管侵犯患者中位生存时间为32．4个月，5年累积生存率为19．6％；血管未侵犯患者中位生存时间为40．7个月，5年累积生存率为42．0％，两者生存情况比较，差异有统计学意义（χ^2=9．364，P〈0．05）。单因素分析结果显示：肿瘤直径、肿瘤分化程度、神经侵犯、血管侵犯、T分期、N分期、TNM分期是影响胃癌患者预后的相关因素（χ^2=9．241，17．486，11．243，9．364，27．666，216．745，49．887，P〈0．05）。多因素分析结果显示：肿瘤直径≥5cm、血管侵犯、T分期为T4期、N分期为N3期、TNM分期为Ⅲ期是影响胃癌患者预后的独立危险因素（HR=0．502，0．456，0．052，0．001，0．735，95％可信区间：0．334—0．754，0．289～0．720，0．004—0．664，0．000～0．006，0．159～3．398，P〈0．05）。结论胃癌患者血管侵犯可能与肿瘤进展有关。肿瘤直径≥5cm、血管侵犯、T分期为T4期、N分期为N3期、TNM分期为Ⅲ期是影响胃癌患者预后的独立危险因素。血管侵犯可作为判断胃癌患者预后不良的指标。

关键词：胃肿瘤血管侵犯预后

Towards data-efficient mechanical design of bicontinuous composites usinggenerative AI

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 57-64页

作者： Milad Masrouri zhao Qin Department of Civil and Environmental Engineering Syracuse UniversitySyracuseNY 13244USA Laboratory for Multiscale Material Modelling Syracuse UniversitySyracuseNY 13244USA The BioInspired Institute Syracuse UniversitySyracuseNY 13244USA

The distribution of material phases is crucial to determine the composite’s mechanical *** the full structure-mechanics relationship of highly ordered material distributions can be studied with finite number of cases,this relationship is difficult to be revealed for complex irregular distributions,preventing design of such material structures to meet certain mechanical *** noticeable developments of artificial intelligence(AI)algorithms in material design enables to detect the hidden structure-mechanics correlations which is essential for designing composite of complex *** is intriguing how these tools can assist composite ***,we focus on the rapid generation of bicontinuous composite structures together with the stress distribution in *** find that generative AI,enabled through fine-tuned Low Rank Adaptation models,can be trained with a few inputs to generate both synthetic composite structures and the corresponding von Mises stress *** results show that this technique is convenient in generating massive composites designs with useful mechanical information that dictate stiffness,fracture and robustness of the material with one model,and such has to be done by several different experimental or simulation *** research offers valuable insights for the improvement of composite design with the goal of expanding the design space and automatic screening of composite designs for improved mechanical functions.

关键词： Generative artificial intelligence Stable diffusion Composite design Phase field model Molecular dynamics simulation

A stochastic gradient-based two-step sparse identification algorithm for multivariate ARX systems

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Control Theory and Technology 2024年第2期22卷 213-221页

作者： Yanxin Fu Wenxiao zhao Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

We consider the sparse identification of multivariate ARX systems, i.e., to recover the zero elements of the unknown parameter matrix. We propose a two-step algorithm, where in the first step the stochastic gradient (SG) algorithm is applied to obtain initial estimates of the unknown parameter matrix and in the second step an optimization criterion is introduced for the sparse identification of multivariate ARX systems. Under mild conditions, we prove that by minimizing the criterion function, the zero elements of the unknown parameter matrix can be recovered with a finite number of observations. The performance of the algorithm is testified through a simulation example.

关键词： ARX system Stochastic gradient algorithm Sparse identification Support recovery Parameter estimation Strong consistency

Opinion Dynamics in Two-Layer Networks with Hypocrisy

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Journal of the Operations Research Society of China 2024年第1期12卷 109-132页

作者： Chi zhao Elena Parilina Saint Petersburg State University Saint Petersburg199034Russia Qingdao University School of Mathematics and StatisticsQingdao 266071ShandongChina

We propose a general concealed voter model(GCVM),in which individuals interact in two layers and can exchange their opinions in the internal *** interaction is not allowed in a *** exchanging opinions in the internal layer,we mean that individuals share their real or internal opinions with their close *** process of opinion formation in GCVM is presented in the *** make the series of numerical simulations of GCVM with different network structures(both external and internal)and get some counterintuitive *** instance,we find out that sometimes with a relatively simple network structure of an external layer the consensus within the individuals’opinions cannot be reached,and if individuals in the network are not good at expressing their opinions publicly(in an external layer),exchanging opinions with their close friends(in an internal layer)is almost useless.

关键词： Opinion dynamics Voter model Concealed voter model General concealed voter model

Retaining the self-released chalcogenate at reconstructed cobalt sites by self-transformed carbonate regulation for boosted oxygen evolution

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Journal of Energy Chemistry 2024年第10期97卷 46-54,I0002页

作者： Jingxuan zhao Zhe Xue Qing Wang Xiangyang Li Shoujie Liu Xu zhao School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina Key Laboratoryof Materials Physics Instituteof Solid State PhysicsHefei Institutes of Physical Science(HFIPS)Chinese Academy of SciencesHefei 23031 Anhui China School of Materials Science and Engineering Anhui UniversityHefei 230601AnhuiChina

The in-situ generated oxyanions at electrochemically reconstructed catalysts from metal-based nonoxide compounds have been proven to significantly accelerate oxygen evolution reaction(OER)***,it remains a challenge to retain these self-released oxyanions at reconstructed catalysts,hindering its utilization as a tool to develop efficient OER ***,we demonstrate a versatile selftransformed carbonate regulation strategy to efficiently retain the self-released chalcogenate at Co oxyhydroxides reconstructed from carbon-incorporated Co selenides under OER *** selftransformed CO_(3)^(2-)can induce electron accumulation and narrow d bond at Co sites to facilitate the Co3d-O 2p orbital hybridization between Co sites and SeO_(x)^(2-)for enhanced SeO_(x)^(2-)retention,which can accelerate the rate-limiting step for^(*)OOH formation during *** to CoOOH-SeO_(x)^(2-)with limited SeO_(x)^(2-)residues,CoOOH-CO_(3)^(2-)/SeO_(x)^(2-)with elevated SeO_(x)^(2-)retention by CO_(3)^(2-)regulation exhibited a 5.6-fold increase in current density and a remarkable lower Tafel slope towards *** strategy paves a rational avenue to design efficient catalysts for electrooxidation reactions through finely regulating self-released oxyanions at reconstructed structures.

关键词： Electrochemical reconstruction Chalcogenate retention Carbonate regulation Orbital hybridization Oxygen evolution reaction

生活垃圾填埋场渗滤液性质随时间变化关系研究

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环境科学学报 2007年第6期27卷 987-992页

作者：楼紫阳柴晓利赵由才宋玉李雄刘振宇同济大学污染控制与资源化研究国家重点实验室上海200092

通过对上海老港填埋场不同年份渗滤液样品的分析,测定了以下参数:电导率、ORP、CODCr、NPOC、NH4+-N、TN、正磷酸盐与总磷、pH、阴离子(F-、Cl-、Br-、SO42-),并建立了各参数与时间的关系.发现不同的渗滤液指标随填埋时间延长,其变化趋... 详细信息

通过对上海老港填埋场不同年份渗滤液样品的分析,测定了以下参数:电导率、ORP、CODCr、NPOC、NH4+-N、TN、正磷酸盐与总磷、pH、阴离子(F-、Cl-、Br-、SO42-),并建立了各参数与时间的关系.发现不同的渗滤液指标随填埋时间延长,其变化趋势略有差异,其中NPOC、COD、N、P、pH、电导率等指标值随时间的延长,总体表现为降低趋势;而ORP则逐渐升高;阴离子等变化趋势不明显,呈现波动趋势.对于相同变化趋势的指标,其降解过程也并不一致,对于含C物质——NPOC和COD,经4a降解后分别达到<500mg·L-1和<2000mg·L-1;对于含N物质,则可分为3个阶段,前4a为快速降解阶段,随后3a为中速降解,最后进入慢速降解阶段稳定在500mg·L-1以内;TP含量随填埋时间在开始的9a内降解迅速,从35mg·L-1降到3.4mg·L-1,此后基本维持稳定值;pH值则在开始的7a内下降较快,随后变化不大;电导率在填埋开始的7年内下降较快;而ORP则在开始的9a内上升较多.同时发现,随着填埋时间的延长,NPOC/TOC、NH4+-N/TN、正磷酸盐/TP比例总体表现为降低,SO24-/Cl-比例稍微有升高,最终保持在0.2左右.

关键词：渗滤液老港填埋场性质表征

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废旧塑料无水清洁装置的设计及其清洗实验

环境工程学报 2017年第4期11卷 2457-2461页

作者：宋楠王罗春周涛孙艳秋周家珍赵由才上海电力学院环境与化学工程学院上海200090 同济大学环境科学与工程学院上海200092

为提高回收塑料识别、分离准确度和再生塑料产品的质量,需对废旧塑料进行清洗。传统的水洗清洁方法会产生大量污染废水,后续的污水处理系统和干燥装置增加了清洗成本。为了克服湿法清洁带来的污染和高成本,设计和运行了一种轻质废旧塑... 详细信息

为提高回收塑料识别、分离准确度和再生塑料产品的质量,需对废旧塑料进行清洗。传统的水洗清洁方法会产生大量污染废水,后续的污水处理系统和干燥装置增加了清洗成本。为了克服湿法清洁带来的污染和高成本,设计和运行了一种轻质废旧塑料无水清洁装置,以廉价砂石和空气作为清洗介质,在不产生二次污染的前提下对废旧塑料膜进行无水清洗。结果表明:无水清洁40 min和50 min的样品清洗率分别达到92.72%和94.90%,接近于水洗样品的94.56%;无水清洁40 min和50 min的样品平均遮光率分别达到43.56%和40.10%,接近于水洗样品的41.84%。

关键词：无水清洁废旧塑料清洗率遮光率