首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
On the example of a finite dimensional approximation of the Kuramoto-Sivashinsky equation we show how topological methods may be successfully used in computer assisted proofs of the existence of heteroclinic connections in ordinary differential equations.  相似文献   

2.
In this paper, we proposed a lattice Boltzmann model based on the higher-order moment method for the Kuramoto-Sivashinsky equation. A series of partial differential equations obtained by using multi-scale technique and Chapman-Enskog expansion. According to Hirt’s heuristic stability theory, the stability of the scheme can be controlled by modulating some special moments to design the fifth-order dispersion term and the sixth-order dissipation term. As results, the Kuramoto-Sivashinsky equation is recovered with higher-order truncation error. The numerical examples show the higher-order moment method can be used to raise the accuracy of the truncation error of the lattice Boltzmann scheme for the Kuramoto-Sivashinsky equation.  相似文献   

3.
The paper is concerned with adaptive stabilization of a reaction-diffusion system governed by the Kuramoto-Sivashinsky equation (a non-linear partial differential equation). Under the existence of bounded deterministic disturbances, the adaptive stabilizer is constructed by the concept of high-gain non-linear output feedback and the estimation mechanism of the unknown parameters. In the control system, the global asymptotic stability and convergence of the system state to zero will be guaranteed. The problem of set point regulation is also considered.  相似文献   

4.
We propose an efficient and generic algorithm for rigorous integration forward in time of partial differential equations written in the Fourier basis. By rigorous integration we mean a procedure which operates on sets and return sets which are guaranteed to contain the exact solution. The presented algorithm generates, in an efficient way, normalized derivatives which are used by the Lohner algorithm to produce a rigorous bound. The algorithm has been successfully tested on several partial differential equations (PDEs) including the Burgers equation, the Kuramoto-Sivashinsky equation, and the Swift-Hohenberg equation. The problem of rigorous integration in time of partial differential equations is a problem of large computational complexity and efficient algorithms are required to deal with PDEs on higher dimensional domains, like the Navier-Stokes equation. Technicalities regarding the various optimization techniques implemented in the software used in this paper will be reported elsewhere.  相似文献   

5.
首先介绍了带有两个辅助参数的改进同伦分析方法,然后用该方法得到了推广Kuramoto-Sivashin-sky方程的同伦近似解.所得近似解与精确孤立波解进行比较,发现本文得到的近似解更有效地逼近真实解.因为该解包含了两个辅助参数,所以能够更有效地调节和控制其收敛区域和速度.研究表明带有两个辅助参数的改进同伦分析方法对复杂非线性系统的研究更有它的优点.  相似文献   

6.
Formation of hexagonal periodic nanoscale structures at the surface of aluminum oxide is considered in the present paper. The mathematical model of chemical reactions at metal-oxide and oxide/electrolyte interfaces is described. A weak nonlinear approximation near the instability threshold results in the two-dimensional Kuramoto-Sivashinsky equation. The solution of this equation provides the same regular hexagonal nanoscale structure arrays that are observed in physical experiments. The two-stage complex Rosenbrock scheme developed by the author is applied for the numerical simulation of this problem in the present paper. The high accuracy O4) and L1 stability, along with the relative simplicity of the method, make it possible to use a conventional PC to perform the calculations.  相似文献   

7.
为了方便临床医生使用医学影像进行手术的规划和引导,提出了一种新颖的计算机辅助肝癌微波消融手术方法.采用基于GPU加速的三维可视化技术实时重构影像的三维模型,显示出患者器官的解剖关系;采用基于生物传热学的三维热场计算技术,规划手术路径及消融设备的作用时间和功率.经过大量的临床应用以及手术影像对比,表明该方法能够有效计算消融手术的作用效果,并在手术的引导过程中发挥了重要的作用,提高了手术的临床精度和效果.  相似文献   

8.
王爱民 《计算机工程与应用》2002,38(22):232-234,248
文章介绍了基于犤1犦中提出的设计理论,开发智能化AutoCAD教学系统的设计思想与实现方法。  相似文献   

9.
Decision theory is a formal basis for considering human decision making. It has typically focused on humans and even if the decision-maker is assisted in the process, it is assumed that the assistance is provided by another human. However, in the computer age the decision-maker is assisted more often than not by a computer. Hence in this paper we explore the rationale for an integrated human-computer information processor and consider the information processing capabilities of the human and the computer within a formal model of decision-making. The analysis for the computer is done assuming it has at least the capabilities of a decision support system.  相似文献   

10.
微信公众平台在教学活动中得到了广泛应用,增强了师生之间的互动。本文以微信公众平台与计算机教学辅 助系统为研究主题,从系统特点、系统原理、系统结构、开发要点、教学模式构建等方面对基于微信平台的计算机教学辅助系统 设计与实现进行研究。  相似文献   

11.
The programme of development of computer assisted learning materials for students of engineering in the higher education sector is described. The concept of the computer experiment is discussed and developed. The use of computer graphics is illustrated with examples taken from current teaching material.  相似文献   

12.
面向大型数据库的审计数据采集方法   总被引:2,自引:0,他引:2  
陈伟  QIU Ro-bin 《计算机应用》2008,28(8):2144-2146
计算机辅助审计是目前审计领域研究的一个热点,审计数据采集是面向数据的计算机辅助审计的关键步骤。分析了常用的审计数据采集方法,比较了各自的优缺点。在此基础上,针对我国实施计算机辅助审计的现状以及面向大型数据库的审计数据采集的特点,分析了适合大型数据库的审计数据采集方法,并以Oracle数据库为例,分析了该方法的应用。  相似文献   

13.
计算机多媒体技术近年来发展成熟,多媒体辅助教学模式被引入到各专业课程教学实践应用中。本文探讨了计算机多媒体辅助教学模式在数学教学中优势,以及在数学教学实践存在的问题。  相似文献   

14.
Computed tomography (CT) imaging remains the most utilized modality for liver-related cancer screening and treatment monitoring purposes. Liver, liver tumor and liver vasculature segmentation from CT data is a prerequisite for treatment planning and computer assisted detection/diagnosis systems. In this paper, we present a survey on liver, liver tumor and liver vasculature segmentation methods that are using CT images, recent methods presented in the literature are viewed and discussed along with positives, negatives and statistical performance of these methods. Liver computer assisted detection/diagnosis systems will also be discussed along with their limitations and possible ways of improvement. In this paper, we concluded that although there is still room for improvement, automatic liver segmentation methods have become comparable to human segmentation. However, the performance of liver tumor segmentation methods can be considered lower than expected in both automatic and semi-automatic methods. Furthermore, it can be seen that most computer assisted detection/diagnosis systems require manual segmentation of liver and liver tumors, limiting clinical applicability of these systems. Liver, liver tumor and liver vasculature segmentation is still an open problem since various weaknesses and drawbacks of these methods can still be addressed and improved especially in tumor and vasculature segmentation along with computer assisted detection/diagnosis systems.  相似文献   

15.
根据“高等数学”教学目前的实际情况,结合自己的教学经验,阐述引入计算机辅助教学的优点.提出将传统教学和计算机辅助教学相结合时自己的认识和建议。  相似文献   

16.
根据"高等数学"教学目前的实际情况,结合自己的教学经验,阐述引入计算机辅助教学的优点,提出将传统教学和计算机辅助教学相结合时自己的认识和建议。  相似文献   

17.
基于用户行为模型的计算机辅助翻译方法   总被引:1,自引:0,他引:1  
与全自动机器翻译相比,计算机辅助翻译技术更具实用性,已成为机器翻译领域的一个研究热点.传统的辅助翻译过程中,用户只能被动接受系统提供的辅助译文,并进行翻译后编辑操作.该文提出一种基于用户行为模型的辅助翻译方法,通过实时记录用户的后编辑过程,分析出用户的翻译决策,建立用户行为模型,使得翻译系统能够动态获取和共享用户的翻译...  相似文献   

18.
The purpose of this study was to establish factors that lead to poor integration of Information and communication technology (ICT) for teaching and learning in schools in Kenya, despite comprehensive policy, institutional, infrastructural frameworks and capacity building by the Ministry of Education. The subject of this study was administered by use of questionnaires in three categories of public schools: national school, provincial schools and district schools. The respondents were students from each level that is from one, two, three and four and teachers based on the most offered subjects in the secondary schools. The computer assisted learning facilities were classified into computers, internet and content in optical media. In national school Internet based research, optical media content provided by Kenya Institute of Curriculum Development and Cyber School program for science subjects was used in learning. In provincial school, it lacks adequate computers, reliable Internet and content in optical media. In district school, it lacks adequate computer, no internet connection and content in optical media. A learner management system which can be accessed by all learners by use of any internet access devices like mobile phone access will be an ideal tool with over 4,000,000 mobile phone subscribers currently in Kenya.  相似文献   

19.
从理论的角度阐述MCAI从研发到设计再到具体制作的全过程,并辅以实例来说明,如何利用多媒体技术将声音、图像、动画等载体将信息融合在一起,通过计算机进行综合和控制的教学方法。  相似文献   

20.
从理论的角度阐述MCAI从研发到设计再到具体制作的全过程,并辅以实例来说明,如何利用多媒体技术将声音、图像、动画等载体将信息融合在一起,通过计算机进行综合和控制的教学方法.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号