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光的衍射的理论分析及Mathematica仿真模拟 被引量:7
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作者 陈学文 罗源源 +1 位作者 张家伟 姚雪 《西南师范大学学报(自然科学版)》 CAS 北大核心 2018年第11期156-161,共6页
首先利用旋转矢量从理论上推出了光的多缝干涉的光强分布公式,并将狭缝数N→!,从而得到光的单缝衍射光强分布,进而在多缝干涉和单缝衍射的基础上得到了光栅衍射光强分布.此外,将Mathematica仿真模拟应用到光的衍射课堂教学中.基于Mathem... 首先利用旋转矢量从理论上推出了光的多缝干涉的光强分布公式,并将狭缝数N→!,从而得到光的单缝衍射光强分布,进而在多缝干涉和单缝衍射的基础上得到了光栅衍射光强分布.此外,将Mathematica仿真模拟应用到光的衍射课堂教学中.基于Mathematica软件的交互功能,利用Mathematica的Manipulate命令对单缝夫琅禾费衍射和光栅衍射做了仿真模拟,获得了相应的可以调节各参数(如波长、狭缝宽度、光栅常数等)的动态图形.这对学生建立清晰的物理图像,更好地理解光的衍射的物理规律有很好的促进作用. 展开更多
关键词 光的衍射 旋转矢量 MATHEMATICA 虚拟仿真
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Mathematical Model of the Spread of the Coronavirus Disease 2019 (COVID-19) in Burkina Faso
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作者 Aboudramane Guiro Blaise Koné Stanislas Ouaro 《Applied Mathematics》 2020年第11期1204-1218,共15页
In this paper, we develop a mathematical model of the COVID-19 pandemic in Burkina Faso. We use real data from Burkina Faso National Health Commission against COVID-19 to predict the dynamic of the disease and also th... In this paper, we develop a mathematical model of the COVID-19 pandemic in Burkina Faso. We use real data from Burkina Faso National Health Commission against COVID-19 to predict the dynamic of the disease and also the cumulative number of reported cases. We use public policies in model in order to reduce the contact rate, this allows to show how the reduction of the daily report of infectious cases goes, so we would like to draw the attention of decision makers for a rapid treatment of reported cases. 展开更多
关键词 COVID-19 STATISTICS Data Exposed Person Reported and Unreported Cases Mathematical Model Public Policies Basic Reproduction Number Prediction
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MathWorks推出与机器人操作系统(ROS)完整集成的Robotics System Toolbox
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《微型机与应用》 2015年第9期70-70,共1页
Math Works近日推出Robotics System Toolbox(机器人系统工具箱),这个新产品是Release 2015a的组成部分。、通过即用型算法和用于开发自动移动机器人应用程序的硬件连接性,Robotics System Toolbox提供了常用的机器人算法,以及MAT... Math Works近日推出Robotics System Toolbox(机器人系统工具箱),这个新产品是Release 2015a的组成部分。、通过即用型算法和用于开发自动移动机器人应用程序的硬件连接性,Robotics System Toolbox提供了常用的机器人算法,以及MATLAB和Simulink与机器人操作系统(ROS)之间的接口和集成。现在,机器人研究人员和工程师们可以在单个统一的设计环境中开发机器人算法,在支持ROS的机器人和机器人仿真器(如Gazebo和V—REP)上测试和部署机器人算法。它通过减少从MATLAB程序转换到ROS程序所需的手动修改时间,留出了更多的时间来测试和调试算法。 展开更多
关键词 TOOLBOX 机器人系统 MATH 操作系统 集成 Simulink MATLAB Release
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A mathematical perspective on the determination of coastal peopling nuclei
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作者 Claude Gauthier Ahcène Brahmi Ghislain Vautour 《Natural Science》 2013年第1期15-21,共7页
Two versions of a mathematical model are proposed for the process underlying the choice of settlement sites of past, present and future populations along the world coastline. The model is primarily based on the geomet... Two versions of a mathematical model are proposed for the process underlying the choice of settlement sites of past, present and future populations along the world coastline. The model is primarily based on the geometry of coastline at the scale of the map representing the region under study. It can be used to determine sites of human occupation for archaeological interest, as well as to plan future movements of present coastal populations due to the current sea level rise. Two examples related to history are presented: the first applies to the coastal peopling of the Mediterranean region, and the second to the settlement of Acadians in North-East of the Canadian province of New Brunswick in the second half of the 18th century. 展开更多
关键词 MATHEMATICAL MODELING COASTAL
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A Mathematical Model of COVID-19: Analysis and Identification of Parameters for Better Decision Making
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作者 Ouaténi Diallo Yaya Kone +2 位作者 Chata Sanogo Jérô me Pousin 《Applied Mathematics》 2022年第2期205-214,共10页
Since the onset of the COVID-19 epidemic, the world has been impressed by two things: The number of people infected and the number of deaths. Here, we propose a mathematical model of the spread of this disease, analyz... Since the onset of the COVID-19 epidemic, the world has been impressed by two things: The number of people infected and the number of deaths. Here, we propose a mathematical model of the spread of this disease, analyze this model mathematically and determine one or more dominant factors in the propagation of the COVID-19 epidemic. We consider the S-E-I-R epidemic model in the form of ordinary differential equations, in a population structured in susceptibles S, exposed E as caregivers, travelers and assistants at public events, infected I and recovered R classes. Here we decompose the recovered class into two classes: The deaths class D and the class of those who are truly healed H. After the model construction, we have calculated the basic reproduction number R<sub>0</sub>, which is a function of certain number of parameters like the size of the exposed class E. In our paper, the mathematical analysis, which consists in searching the equilibrium points and studying their stability, is done. The work identifies some parameters on which one can act to control the spread of the disease. The numerical simulations are done and they illustrate our theoretical analysis. 展开更多
关键词 COVID-19 Mathematical Model R0 SPREAD Control Parameters Malian Data
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Mathematical Model of Dynamics of Micropolar Orthotropic Elastic Thin Bars with Free Fields of Displacements and Rotations
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作者 Sargsyan Samvel Margaryan Lilit 《Journal of Mechanics Engineering and Automation》 2012年第2期110-118,共9页
In the present paper, initial-boundary value problem of plane stress state of micropolar theory of elasticity is considered for orthotropic material in the domain of thin rectangle. General hypotheses are formulated, ... In the present paper, initial-boundary value problem of plane stress state of micropolar theory of elasticity is considered for orthotropic material in the domain of thin rectangle. General hypotheses are formulated, which are the qualitative results of the asymptotic method of integration of the stated initial-boundary value problem. On the basis of the accepted hypotheses general applied one-dimensional models of dynamics of bending deformation of micropolar orthotropic elastic thin bars with free fields of displacements and rotations are constructed with and without consideration of shear deformations. With the help of the constructed models different dynamic problems of micropolar bars can be studied. Here concrete problems of free and forced vibrations of hinged supported micropolar orthotropic elastic thin bar are studied. Numerical analysis is done and specific features of dynamic characteristics of micropolar material are revealed. Particularly, it is shown that there is a frequency of vibrations of the micropolar bar that does not depend on bar sizes. 展开更多
关键词 DYNAMICS MICROPOLAR ORTHOTROPIC mathematical model free and forced vibrations.
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GLOBAL BIFURCATION AND CHAOS IN A VAN DER POL-DUFFING-MATHIUE SYSTEM WITH A SINGLE-WELL POTENTIAL OSCILLATOR 被引量:1
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作者 Xu, J Wang, C +1 位作者 Chen, YS Lu, QS 《Acta Mechanica Solida Sinica》 SCIE EI 1997年第3期262-275,共14页
The global bifurcation and chaos are investigated in this paper for a van der Pol-Duffing-Mathieu system with a single-well potential oscillator by means of nonlinear dynamics. The autonomous system corresponding to t... The global bifurcation and chaos are investigated in this paper for a van der Pol-Duffing-Mathieu system with a single-well potential oscillator by means of nonlinear dynamics. The autonomous system corresponding to the system under discussion is analytically studied to draw all global bifurcation diagrams in every parameter space. These diagrams are called basic bifurcation ones. Then fixing parameter in every space and taking the parametrically excited amplitude as a bifurcation parameter, we can observe how to evolve from a basic bifurcation diagram to a chaos pattern in terms of numerical methods. The results are sufficient to show that the system has distinct dynamic behavior. Finally, the properties of the basins of attraction are observed and the appearance of fractal basin boundaries heralding the onset of a loss of structural integrity is noted in order to consider how to control the extent and the rate of the erosion in the next paper. 展开更多
关键词 global bifurcation CHAOS nonlinear vibration basin FRACTAL
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Applying a Mathematical Model to the Performance of a Female Monofin Swimmer 被引量:1
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作者 Elisée Gouba Balira Ousmane Konfe +2 位作者 Ousseynou Nakoulima Blaise Some Olivier Hue 《Applied Mathematics》 2013年第12期1673-1681,共9页
This study sought to determine the best method to quantify training based on heart rate data. It proposes a modification of Banister’s original performance model to improve the accuracy of predicted performance. The ... This study sought to determine the best method to quantify training based on heart rate data. It proposes a modification of Banister’s original performance model to improve the accuracy of predicted performance. The new formulation introduces a variable that accounts for changes in the subject’s initial performance as a result of the quantity of training. The two systems models were applied to a well-trained female monofin swimmer over a 24-week training period. Each model comprised a set of parameters unique to the individual and was estimated by fitting model-predicted performance to measured performance. We used the Alienor method associated to Optimization-Preserving Operators to identify these parameters. The quantification method based on training intensity zones gave a better estimation of predicted performance in both models. Using the new model in sports in which performance is generally predicted (running, swimming) will help us to define its real interest. 展开更多
关键词 TRAINING Quantification Banister’s MODEL
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SIEMENS AUTOMATION和MATHWORKS在仿真与基于模型的设计方面展开协作
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《微型机与应用》 2015年第1期96-96,共1页
MathWorks近日宣布,与Siemens Automation Systems拓展关系,使客户能够更加方便地利用基于模型的设计来开发和实施复杂的控制算法。控制工程师们现在可以从Simulink生成代码,然后将其部署到SiemensSIMATICS7模块化PLC控制器和SIMATIC... MathWorks近日宣布,与Siemens Automation Systems拓展关系,使客户能够更加方便地利用基于模型的设计来开发和实施复杂的控制算法。控制工程师们现在可以从Simulink生成代码,然后将其部署到SiemensSIMATICS7模块化PLC控制器和SIMATICWinACRTX软件控制器。因此,在PLC硬件上执行进一步验证前,可以使用仿真来设计和测试高级控制策略以证明概念的可行性。为了支持这一集成,SiemensAutomationSystems还加入了MathWorksConnectionsProgram。 展开更多
关键词 AUTOMATION 基于模型 SIEMENS 设计 仿真 AUTOMATION PLC控制器 SIMULINK
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Automated classification technique for edge-on galaxies based on mathematical treatment of brightness data
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作者 Mohamed Eassa Ibrahim Mohamed Selim +1 位作者 Walid Dabour Passent Elkafrawy 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第10期231-238,共8页
Classification of edge-on galaxies is important to astronomical studies due to our Milky Way galaxy being an edge-on galaxy.Edge-on galaxies pose a problem to classification due to their less overall brightness levels... Classification of edge-on galaxies is important to astronomical studies due to our Milky Way galaxy being an edge-on galaxy.Edge-on galaxies pose a problem to classification due to their less overall brightness levels and smaller numbers of pixels.In the current work,a novel technique for the classification of edge-on galaxies has been developed.This technique is based on the mathematical treatment of galaxy brightness data from their images.A special treatment for galaxies’brightness data is developed to enhance faint galaxies and eliminate adverse effects of high brightness backgrounds as well as adverse effects of background bright stars.A novel slimness weighting factor is developed to classify edge-on galaxies based on their slimness.The technique has the capacity to be optimized for different catalogs with different brightness levels.In the current work,the developed technique is optimized for the EFIGI catalog and is trained using a set of 1800 galaxies from this catalog.Upon classification of the full set of 4458 galaxies from the EFIGI catalog,an accuracy of 97.5% has been achieved,with an average processing time of about 0.26 seconds per galaxy on an average laptop. 展开更多
关键词 techniques:image processing methods:data analysis galaxies:formation
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Erratum to “Manifolds with Bakry-Emery Ricci Curvature Bounded Below”, Advances in Pure Mathematics, Vol. 6 (2016), 754-764
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作者 Issa Allassane Kaboye Bazanfaré Mahaman 《Advances in Pure Mathematics》 2017年第11期647-648,共2页
The original online version of this article (Issa Allassane Kaboye, Bazanfaré Mahaman (2016) Manifolds with Bakry-Emery Ricci Curvature bounded below 6, 754-764. http://dx.doi.org/10.4236/apm.2016.611061 unfortun... The original online version of this article (Issa Allassane Kaboye, Bazanfaré Mahaman (2016) Manifolds with Bakry-Emery Ricci Curvature bounded below 6, 754-764. http://dx.doi.org/10.4236/apm.2016.611061 unfortunately contains a mistake. The author wishes to correct the errors. 展开更多
关键词 Erratum
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Exploring Zika's dynamics:A scoping review journey from epidemic to equations through mathematical modelling
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作者 Jhoana P.Romero-Leiton Elda K.E.Laison +4 位作者 Rowin Alfaro E.Jane Parmley Julien Arino Kamal R.Acharya Bouchra Nasri 《Infectious Disease Modelling》 2025年第2期536-558,共23页
Zika virus(ZIKV)infection,along with the concurrent circulation of other arboviruses,presents a great public health challenge,reminding the utilization of mathematical modelling as a crucial tool for explaining its in... Zika virus(ZIKV)infection,along with the concurrent circulation of other arboviruses,presents a great public health challenge,reminding the utilization of mathematical modelling as a crucial tool for explaining its intricate dynamics and interactions with co-circulating pathogens.Through a scoping review,we aimed to discern current mathematical models investigating ZIKV dynamics,focusing on its interplay with other pathogens,and to identify underlying assumptions and deficiencies supporting attention,particularly regarding the epidemiological attributes characterizing Zika outbreaks.Following the PRISMA-Sc guidelines,a systematic search across PubMed,Web of Science,and MathSciNet provided 137 pertinent studies from an initial pool of 2446 papers,showing a diversity of modelling approaches,predominantly centered on vector-host compartmental models,with a notable concentration on the epidemiological landscapes of Colombia and Brazil during the 2015–2016 Zika epidemic.While modelling studies have been important in explaining Zika transmission dynamics and their intersections with diseases such as Dengue,Chikungunya,and COVID-19 so far,future Zika models should prioritize robust data integration and rigorous validation against diverse datasets to improve the accuracy and reliability of epidemic prediction.In addition,models could benefit from adaptable frameworks incorporating human behavior,environmental factors,and stochastic parameters,with an emphasis on open-access tools to foster transparency and research collaboration. 展开更多
关键词 Zika virus Mathematical modelling ARBOVIRUSES EPIDEMIOLOGY Public health
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Mathematical modeling of contact tracing and stability analysis to inform its impact on disease outbreaks;an application to COVID-19
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作者 Mohamed Ladib Aziz Ouhinou Abdul-Aziz Yakubu 《Infectious Disease Modelling》 CSCD 2024年第2期329-353,共25页
We develop a mathematical model to investigate the effect of contact tracing on containing epidemic outbreaks and slowing down the spread of transmissible diseases.We propose a discrete-time epidemic model structured ... We develop a mathematical model to investigate the effect of contact tracing on containing epidemic outbreaks and slowing down the spread of transmissible diseases.We propose a discrete-time epidemic model structured by disease-age which includes general features of contact tracing.The model is fitted to data reported for the early spread of COVID-19 in South Korea,Brazil,and Venezuela.The calibrated values for the contact tracing parameters reflect the order pattern observed in its performance intensity within the three countries.Using the fitted values,we estimate the effective reproduction number R_(e)and investigate its responses to varied control scenarios of contact tracing.Alongside the positivity of solutions,and a stability analysis of the disease-free equilibrium are provided. 展开更多
关键词 Mathematical modeling Infectious diseases Discrete systems Disease-age structured populations Contact tracing Effective reproduction number COVID-19
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多模态视觉语言表征学习模型及其对抗样本攻防技术综述
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作者 曾诚 葛云洁 +1 位作者 赵令辰 王骞 《计算机研究与发展》 北大核心 2025年第9期2208-2232,共25页
随着计算机视觉、自然语言处理与深度学习技术的快速发展,多模态视觉语言表征学习模型在图像描述、文本生成图像、视觉问答等任务中展现出了卓越的性能,已成为当前学术界与工业界共同关注的研究热点.然而,这类模型的多模态特性和复杂性... 随着计算机视觉、自然语言处理与深度学习技术的快速发展,多模态视觉语言表征学习模型在图像描述、文本生成图像、视觉问答等任务中展现出了卓越的性能,已成为当前学术界与工业界共同关注的研究热点.然而,这类模型的多模态特性和复杂性为攻击者提供了更加多样的攻击途径,攻击者可以通过对抗样本引导模型输出错误的、有害的或虚假的内容,使该类模型面临的安全威胁日益严峻.系统地梳理了多模态视觉语言模型的研究现状,同时,对近年来出现的针对该类模型的对抗样本攻击方法及其防御策略进行了分类总结,详细归纳了相关研究的基本原理、实施方法与研究结论.在此基础上,对多模态视觉语言表征学习的安全研究现状与未来方向进行了探讨,并展望了视觉语言表征学习技术在未来结合可解释性技术的应用前景. 展开更多
关键词 表征学习 视觉语言学习 对抗性攻击 对抗性防御 网络空间安全
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面向单目可见光环境的自适应双手重建网络
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作者 廖国琼 黄龙杰 +2 位作者 李清新 辜勇 李海波 《图学学报》 北大核心 2025年第4期837-846,共10页
准确重建双手手部网格对于自然的人机交互体验来说是一个至关重要的过程,但由于双手的遮挡、户外收集双手交互数据集的复杂性和复杂的光照环境干扰等因素导致双手手部重建任务仍极具挑战性。目前已有的工作大多是在环境干扰比较小的实... 准确重建双手手部网格对于自然的人机交互体验来说是一个至关重要的过程,但由于双手的遮挡、户外收集双手交互数据集的复杂性和复杂的光照环境干扰等因素导致双手手部重建任务仍极具挑战性。目前已有的工作大多是在环境干扰比较小的实验室等场景下取得的的良好效果,而在复杂的光照场景中的重建效果仍不佳。为了解决上述问题,提出一种面向单目可见光环境的自适应手部重建网络。通过引入单手检测框和使用2D复杂光照场景数据集进行弱监督等策略使得模型得以对复杂光照场景产生泛化性;设计的双手特征交互器得以有效建立左右手特征的远距离依赖关系,缓解了单手检测框缺乏双手交互信息的问题;针对如何有效融合交互特征与单手特征的问题,设计了自适应融合的策略,增强了模型的鲁棒性。实验结果表明,在包含多个复杂光照场景的HIC数据集中取得了最佳的效果。 展开更多
关键词 复杂光照场景 手部网格 双手交互 弱监督 特征融合
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基于Internet+“运筹学”课程教学改革探索——以农林院校为例
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作者 占青义 谢向东 《教育教学论坛》 2025年第36期151-154,共4页
新时代,随着人工智能技术的发展,高校“运筹学”课程教学面临着比较显著的困难。如何从实际出发,切实有效提高“运筹学”的教学效果成为一个比较迫切的教改课题。通过参考国内外同行的经验,结合笔者多年的教学实践,从提高“运筹学”课... 新时代,随着人工智能技术的发展,高校“运筹学”课程教学面临着比较显著的困难。如何从实际出发,切实有效提高“运筹学”的教学效果成为一个比较迫切的教改课题。通过参考国内外同行的经验,结合笔者多年的教学实践,从提高“运筹学”课程教学效果的角度,基于“Internet+”深度理性地审视农林院校“运筹学”课程教学困境,拟在优化教学内容的选择与组织、重视数学基础理论、强化非线性规划的教与学、加强实践教学与算法改进等四个方面,提出课程教学改革的优化策略,并通过教学实践,进一步验证方法的适用性和可行性,以期为其他高校“运筹学”教学改革与课程建设提供借鉴与参考。 展开更多
关键词 运筹学 线性规划 函数的极值 线性方程组的求解 教学改革
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基于最小二乘的量化评估页岩气压裂改造效果方法
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作者 邓才 孙可心 +1 位作者 文欢 胡朝浪 《工程科学与技术》 北大核心 2025年第4期103-111,共9页
在页岩气压裂改造过程中,水平井分段多簇压裂技术是实现页岩气高效开发的关键技术之一,但这项技术缺乏低成本、可量化的评价方法。页岩气压裂改造效果的好坏通常通过井下射孔的有效开启个数来判断,有效孔眼开启得多,则压裂改造效果好,... 在页岩气压裂改造过程中,水平井分段多簇压裂技术是实现页岩气高效开发的关键技术之一,但这项技术缺乏低成本、可量化的评价方法。页岩气压裂改造效果的好坏通常通过井下射孔的有效开启个数来判断,有效孔眼开启得多,则压裂改造效果好,反之则差。针对目前页岩气压裂改造技术评估的瓶颈,本文设计一种基于非线性最小二乘的量化评估模型,该模型结合井下各项摩阻理论与孔眼扩展方程,实现了有效开启射孔数的高效计算。首先,根据压裂过程中阶梯降排量测试中的总摩阻(井筒摩阻、孔眼摩阻、近井摩阻之和)与压裂液排量的对应关系,构造了页岩气摩阻拟合的非线性最小二乘目标函数,从而拟合出各项摩阻系数,尤其是孔眼摩阻系数;然后,结合孔眼摩阻方程和孔眼扩展方程,创建了射孔有效开启孔数和磨蚀后射孔平均直径的计算模型;最后,将该模型应用于工业生产,根据有效开启射孔数和磨蚀后射孔平均直径的计算结果,得到该井段水平井分段多簇压裂改造的实施效果评估依据。在摩阻拟合方面,相比原有模型,本文模型具有可区分所有拟合参数的优点,并且添加了符合工程实际的约束条件,使得拟合结果符合工程需求。所提出的评估方法具有数学理论完备的优点,且实施成本低、效率高,可作为评价压裂改造的新方法。 展开更多
关键词 页岩气开采 水平井分段多簇压裂 摩阻拟合 非线性最小二乘 有效开启孔数
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病例队列设计下乳腺癌患者雌二醇水平及其生存数据的联合建模研究
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作者 吴梦娟 张涛 +2 位作者 高春洁 赵婷 王蕾 《中国全科医学》 北大核心 2025年第14期1765-1772,共8页
背景乳腺癌是一种性激素受体依赖的恶性肿瘤,雌二醇(E2)的动态变化在乳腺癌发展过程中起着非常重要的作用;经典病例队列设计完全忽略未选入样本的信息,容易产生估计偏倚。目的探究乳腺癌患者E2水平动态变化对其生存预后的影响,评估改良... 背景乳腺癌是一种性激素受体依赖的恶性肿瘤,雌二醇(E2)的动态变化在乳腺癌发展过程中起着非常重要的作用;经典病例队列设计完全忽略未选入样本的信息,容易产生估计偏倚。目的探究乳腺癌患者E2水平动态变化对其生存预后的影响,评估改良病例队列设计的优良性。方法对2015—2019年于新疆医科大学附属肿瘤医院经病理学检查确诊为乳腺癌的8226例患者进行随访,以患者确诊时间作为随访时间起点、患者因乳腺癌死亡为结局事件,随访截止日期为2021-12-31。收集患者的人口学特征、免疫组化指标、临床病理特征以及生存状态等,并对患者的血清E2水平进行纵向测量。基于经典病例队列设计,通过纳入病例队列样本外患者的生存数据改良病例队列设计。在经典及改良病例队列设计下采用线性混合效应模型和Cox比例风险模型分别拟合乳腺癌患者的纵向数据(纵向子模型)和生存数据(生存子模型),并建立纵向与时间-事件数据的联合模型;进一步采用马尔可夫链蒙特卡罗算法对联合模型参数进行估计;此外,通过受试者工作特征曲线下面积(AUC)以及预测误差(PE)比较经典及改良病例队列设计下联合模型的区分度与校准度。结果基于纳入与排除标准,本研究全队列中共纳入895例乳腺癌患者作为研究对象,其中53例患者因乳腺癌死亡。患者中位随访时间约为28个月。从全队列中抽取1/4的患者作为随机子队列,与随机子队列外在随访期间死亡的患者合并作为经典病例队列设计的样本,其中,包含236例患者的生存数据、1062人次E2水平的测量值。此外,在经典病例队列设计的基础上,纳入经典病例队列样本之外在随访期间存活的乳腺癌患者(G_(4))的生存数据,作为改良病例队列设计的样本(共包含895例患者的生存数据、236例患者1062人次的E2水平测量值,其中认为存在2958人次E2水平测量的纵向缺失值)。经典和改良病例队列设计下的联合模型结果均显示E2水平动态变化是乳腺癌患者预后的影响因素,且lg(E2)纵向每增加1个单位,患者的死亡风险将分别增加23%(HR=1.23,R^=1.015)和8%(HR=1.08,R^=1.020)。此外,改良病例队列设计下的联合模型展现出更好的区分度与校准度(AUC=0.706~0.962,PE=0.0012~0.0108)。结论乳腺癌患者E2水平纵向升高可能会导致患者生存概率降低。病例队列设计下联合模型能够对纵向与生存数据同时进行分析,且改良病例队列设计优于经典病例队列设计。 展开更多
关键词 乳腺癌 雌二醇 病例队列设计 联合模型 生存数据
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