检索结果-南通市图书馆

First Passage Density of Brownian Motion with Two-sided Piecewise Linear Boundaries

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第6期40卷 1505-1520页

作者： Zhen yu Mao Zai TIAN Center for Applied Statistics School of StatisticsRenmin University of ChinaBeijing 100872P.R.China School of Mathematics and Data Science Changji UniversityChangji 831100P.R.China

The first passage time has many applications in fields like finance,econometrics,statistics,and ***,explicit formulas for the first passage density have only been obtained for a few *** paper derives an explicit formula for the first passage density of Brownian motion with twosided piecewise continuous boundaries which may have some points of *** are used to obtain a simplified formula for estimating the first passage ***,the results are also generalized to the case of two-sided general nonlinear *** can be easily carried out with Monte Carlo method and it is demonstrated for several typical two-sided boundaries that the proposed approximation method offers a highly accurate approximation of first passage density.

关键词： Boundary non-crossing probability first density passage density two-sided piecewise continuous boundaries Brownian motion

Type I interferon pathway in pediatric systemic lupus erythematosus

在线全文

学校读者我要写书评

暂无评论

World Journal of Pediatrics 2024年第7期20卷 653-668页

作者： yu Zhou Hong‑Mei Song Department of Pediatrics Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijingChina State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalBeijingChina

Background The role of type I interferon(IFN-I)signaling in systemic lupus erythematosus(SLE)has been well ***,unanswered questions remain regarding the applicability of these findings to pediatric-onset *** aim of this review is to provide an overview of the novel discoveries on IFN-I signaling in pediatric-onset *** sources A literature search was conducted in the PubMed database using the following keywords:“pediatric systemic lupus erythematosus”and“type I interferon”.Results IFN-I signaling is increased in pediatric SLE,largely due to the presence of plasmacytoid dendritic cells and pathways such as cyclic GMP-AMP synthase–stimulator of interferon genes–TANK-binding kinase 1 and Toll-like receptor(TLR)4/*** extracellular traps and oxidative DNA damage further stimulate IFN-I *** variants in IFN-I-related genes,such as IFN-regulatory factor 5 and tyrosine kinase 2,are linked to SLE susceptibility in pediatric *** addition,type I interferonopathies,characterized by sustained IFN-I activation,can mimic SLE symptoms and are thus important to *** on interferonopathies also contribute to exploring the pathogenesis of *** IFN-I activation is crucial for SLE diagnosis and *** IFNstimulated gene expression and serum IFN-α2 levels are common *** cytometry markers such as CD169 and galectin-9 are promising ***-IFN therapies,such as sifalimumab and anifrolumab,show promise in adult patients with SLE,but their efficacy in pediatric patients requires further *** kinase inhibitors are another treatment option for severe pediatric SLE *** This review presents an overview of the IFN-I pathway in pediatric *** the intricate relationship between IFN-I and pediatric SLE may help to identify potential diagnostic markers and targeted therapies,paving the way for improved patient care and outcomes.

关键词： Interferonopathies Pediatric systemic lupus erythematosus Type I interferon

Relation Between the Eventual Continuity and the E-property for Markov-Feller Semigroups

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第1期40卷 1-16页

作者： Yong Liu Zi-yu Liu LMAM School of Mathematical SciencePeking UniversityBeijing100871China

We investigate some relations between two kinds of semigroup regularities, namely the e-property and the eventual continuity, both of which contribute to the ergodicity for Markov processes on Polish *** precisely, we prove that for Markov-Feller semigroup in discrete time and stochastically continuous MarkovFeller semigroup in continuous time, if there exists an ergodic measure whose support has a nonempty interior,then the e-property is satisfied on the interior of the support. In particular, it implies that, restricted on the support of each ergodic measure, the e-property and the eventual continuity are equivalent for the discrete-time and the stochastically continuous continuous-time Markov-Feller semigroups.

关键词： Markov-Feller semigroup ergodicity e-property eventual continuity

Relative Broken Family Sensitivity

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第9期40卷 2297-2306页

作者： Zhuo Wei LIU Tao yu Department of Mathematics Shantou UniversityShantou 515063P.R.China

Letπ:(X,T)→(Y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of *** introduce the notion of relative broken *** Fs(***,Finf)be the families consisting of all syndetic subsets(*** upper Banach density subsets,infinite subsets).We show that for a factor mapπ:(X,T)→(Y,S)between transitive systems,πis relatively broken F-sensitive for F=Fs or Fpubd if and only if there exists a relative sensitive pair which is an F-recurrent point of(R_(π),T^((2)));is relatively broken Finf-sensitive if and only if there exists a relative sensitive pair which is not *** a factor mapπ:(X,T)→(Y,S)between minimal systems,we get the structure of relative broken F-sensitivity by the factor map to its maximal equicontinuous factor.

关键词： Relative sensitivity recurrent points Furstenberg family relative sensitive pairs maximal equicontinuous factor

On Stability Discrimination of Limit Cycles for Piecewise Smooth Systems

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第7期40卷 1785-1803页

作者： Mao An HAN Xia yu ZHOU School of Mathematical Sciences Zhejiang Normal UniversityJinhua321004P.R.China

This paper is concerned with the problem of stability discrimination of limit cycles for piecewise smooth *** first establish the Poincaré map near a periodic orbit,and deduce the first order derivative of the map for general piecewise smooth systems on the ***,we obtain a sufficient condition for determining the stability of limit cycles for these systems.

关键词： Piecewise smooth system limit cycle stability

An experimental study on effects of temperature gradient on microstructure of a 308L stainless steel manufactured by directed energy deposition

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第8期31卷 2031-2040页

作者： Ting Dai De-yu Gu yu-wen Qiu Wei Guo Hui Ding Yi-wei Sun School of Materials Science and Engineering Jiangsu Key Laboratory of Advanced Metallic MaterialsSoutheast UniversityNanjing 211189JiangsuChina

The effect of spatial temperature gradient on the microstructural evolution of a 308L stainless steel during the directed energy deposition(DED)process was experimentally investigated.A novel cooling system was designed and incorporated to a DED system in order to control the temperature gradient along the deposition direction during *** deposition,the workpiece was placed on a lifting platform,and as the deposition process proceeded,the platform and workpiece were gradually lowered into cooling water so that the temperature gradient along the deposition direction could be controlled and maintained stable during the deposition *** microstructure characterization results indicated that a deposition strategy with higher G and G/R values(where G is temperature gradient and R is solidification rate)produced finer cellular grains that were better aligned with the deposition direction,while a deposition strategy with lower G and G/R values produced columnar grains with larger primary arm spacing and less aligned with the deposition direction.

关键词： Additive manufacturing Directed energy deposition Stainless steel Microstructure Temperature gradient

Trudinger–Moser Inequalities on a Closed Riemann Surface with a Symmetric Conical Metric

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2024年第9期40卷 2263-2284页

作者： yu FANG yun Yan YANG College of Teacher Education Quzhou UniversityQuzhou 324003P.R.China Department of Mathematics Renmin University of ChinaBeijing 100872P.R.China

This is a continuation of our previous work(*** ***.,20,1295–1324,2020).Let(Σ,g)be a closed Riemann surface,where the metric g has conical singularities at finite *** G is a group whose elements are isometries acting on(Σ,g).Trudinger–Moser inequalities involving G are established via the method of blow-up analysis,and the corresponding extremals are also *** extends previous results of Chen(***.,1990),Iula–Manicini(Nonlinear Anal.,2017),and the authors(2020).

关键词： Trudinger-Moser inequality blow-up analysis conical singularity

Cable-driven legged landing gear for unmanned helicopter:Prototype design,optimization and performance assessment

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第4期67卷 1196-1214页

作者： TIAN BaoLin GAO HaiBo yu HaiTao SHAN HaoMin HOU JunChen yu HongYing DENG ZongQuan State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China China Academy of Aerospace Science and Innovation Beijing 100048China

Unmanned helicopters equipped with adaptive landing gear will dramatically extend their application especially in dealing with challenging *** study presents a novel cable-driven legged landing gear(CLG)with differential transmission for unmanned helicopters in complex landing *** obtain the preferred configuration of the legged mechanism,a multi-objective optimization framework for the CLG is constructed by concurrently considering terrain adaptability,landing stability and reasonable linkage of internal *** non-dominated sorting genetic algorithmⅡis employed to numerically acquire the optimal scale parameters that guide the mechanical design of the *** unmanned helicopter prototype equipped with the devised CLG is developed with key performance *** results show that the devised CLG can provide energy-efficient support over uneven terrains(totally driven torque demand less than 0.1 N m)in quasi-static landing tests,and favorable terrain adaptability(posture fluctuation of the fuselage less than±1°)in unknown slope landing *** exhibited merits give the proposed CLG the potential to enhance the landing performance of future aircraft in extreme environments.

关键词： unmanned helicopter adaptive landing gear experimental verification

Unveiling the Contribution of Lactic Acid to the Passivation Behavior of Ti-6Al-4V Fabricated by Laser Powder Bed Fusion in Hank’s Solution

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 102-118页

作者： yu-Hang Chu Liang-yu Chen Bo-yuan Qin Wenbin Gao Fanmin Shang Hong-yu Yang Lina Zhang Peng Qin Lai-Chang Zhang School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100China Foshan(Southern China)Institute for New Materials Foshan528200China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

In actual physiological environments,bacteria can activate the immune system and release lactic ***,the detailed contribution of lactic acid to the passivation behavior of titanium(Ti)alloys is still *** current work investigated the in vitro passivation behavior of Ti-6Al-4V(TC4)alloys fabricated by laser powder bed fusion in Hank's solution with and without adding lactic *** methods,inductively coupled plasma atomic emission spectrometer,and X-ray photoelectron spectroscopy were jointly *** lactic acid decreases the corrosion resistance of samples by degrading the formed passive *** film formed in the(lactic acid)-containing solution exhibits a higher level of oxygen vacancies and a lower thickness,attributed to the suppressed formation of Ti^(4+)transformed from Ti^(3+)and Ti^(2+).Moreover,the presence of lactic acid would increase the open circuit potential,relieve the ions release,and hinder the deposition of calcium phosphates within 24 h immersion.

关键词： Titanium alloy Corrosion behavior Passive film Lactic acid Laser powder bed fusion