In this paper, we propose a weighted Runge-Kutta (WRK) method to solvethe 2D acoustic and elastic wave equations. This method successfully suppresses thenumerical dispersion resulted from discretizing the wave equatio...In this paper, we propose a weighted Runge-Kutta (WRK) method to solvethe 2D acoustic and elastic wave equations. This method successfully suppresses thenumerical dispersion resulted from discretizing the wave equations. In this method,the partial differential wave equation is first transformed into a system of ordinarydifferential equations (ODEs), then a third-order Runge-Kutta method is proposedto solve the ODEs. Like the conventional third-order RK scheme, this new methodincludes three stages. By introducing a weight to estimate the displacement and itsgradients in every stage, we obtain a weighted RK (WRK) method. In this paper, weinvestigate the theoretical properties of the WRK method, including the stability criteria, numerical error, and the numerical dispersion in solving the 1D and 2D scalarwave equations. We also compare it against other methods such as the high-ordercompact or so-called Lax-Wendroff correction (LWC) and the staggered-grid schemes.To validate the efficiency and accuracy of the method, we simulate wave fields in the2D homogeneous transversely isotropic and heterogeneous isotropic media. We conclude that the WRK method can effectively suppress numerical dispersions and sourcenoises caused in using coarse grids and can further improve the original RK methodin terms of the numerical dispersion and stability condition.展开更多
针对当前操作系统内核安全实验大多采用开放源码的Linux,而缺少Windows内核安全实验的问题,基于微软的Windows Research Kernel(WRK)和Hook等技术设计了一组操作系统安全实验,包括文件监控、键盘监听、进程隐藏和网络抓包等。教学实践表...针对当前操作系统内核安全实验大多采用开放源码的Linux,而缺少Windows内核安全实验的问题,基于微软的Windows Research Kernel(WRK)和Hook等技术设计了一组操作系统安全实验,包括文件监控、键盘监听、进程隐藏和网络抓包等。教学实践表明,这些实验能够帮助学生加深对Windows内核安全机制的理解,提升系统安全实践能力。展开更多
本文在分析进程冻结与恢复所涉及的相关知识点基础上,给出了基于WRK(Windows Research Kernel)实现Windows进程冻结与恢复的技术方案。通过将相关知识点按照相关性和难度分类,设计并实施了一种基于研究性学习法的教学方式,使学生变被动...本文在分析进程冻结与恢复所涉及的相关知识点基础上,给出了基于WRK(Windows Research Kernel)实现Windows进程冻结与恢复的技术方案。通过将相关知识点按照相关性和难度分类,设计并实施了一种基于研究性学习法的教学方式,使学生变被动学习为主动学习,提高了综合分析能力和动手能力,取得了满意的教学效果。展开更多
作为一门理论与实践并重的课程,《操作系统》在计算机本科教学体系中占有重要的地位。课程的特点是:概念抽象、知识点多、逻辑分散。因此,理论课中学习到的原理、方法、算法,一定要通过实践才能充分的理解和吸收。然而由于操作系统自身...作为一门理论与实践并重的课程,《操作系统》在计算机本科教学体系中占有重要的地位。课程的特点是:概念抽象、知识点多、逻辑分散。因此,理论课中学习到的原理、方法、算法,一定要通过实践才能充分的理解和吸收。然而由于操作系统自身的庞大和复杂,一般课程实验多以模拟、测试为主,很少能够真正深入系统内部进行动态观测,大大降低了实验的效果。因此,如何合理的设计操作系统实验一直都是一个具有挑战性的课题。WRK全称"Windows Research Kernel"。展开更多
微软在WRK(Windows Research Kernel)中开放了大部分Windows Server 2003的代码,这对高校了解Windows操作系统内核、设计操作系统实验提供了一个很好的基础。但是由于WRK的代码量很大,在缺乏指导的情况下学生很难有效地在WRK上完成操作...微软在WRK(Windows Research Kernel)中开放了大部分Windows Server 2003的代码,这对高校了解Windows操作系统内核、设计操作系统实验提供了一个很好的基础。但是由于WRK的代码量很大,在缺乏指导的情况下学生很难有效地在WRK上完成操作系统原理实验。本文在分析WRK进程工作集的基础上,设计了三个针对工作集的实验,并给出了实验效果验证方法。展开更多
基金This work was supported by the National Science Fund for Distinguished Young Scholars of China(Grant No.40725012).
文摘In this paper, we propose a weighted Runge-Kutta (WRK) method to solvethe 2D acoustic and elastic wave equations. This method successfully suppresses thenumerical dispersion resulted from discretizing the wave equations. In this method,the partial differential wave equation is first transformed into a system of ordinarydifferential equations (ODEs), then a third-order Runge-Kutta method is proposedto solve the ODEs. Like the conventional third-order RK scheme, this new methodincludes three stages. By introducing a weight to estimate the displacement and itsgradients in every stage, we obtain a weighted RK (WRK) method. In this paper, weinvestigate the theoretical properties of the WRK method, including the stability criteria, numerical error, and the numerical dispersion in solving the 1D and 2D scalarwave equations. We also compare it against other methods such as the high-ordercompact or so-called Lax-Wendroff correction (LWC) and the staggered-grid schemes.To validate the efficiency and accuracy of the method, we simulate wave fields in the2D homogeneous transversely isotropic and heterogeneous isotropic media. We conclude that the WRK method can effectively suppress numerical dispersions and sourcenoises caused in using coarse grids and can further improve the original RK methodin terms of the numerical dispersion and stability condition.
文摘针对当前操作系统内核安全实验大多采用开放源码的Linux,而缺少Windows内核安全实验的问题,基于微软的Windows Research Kernel(WRK)和Hook等技术设计了一组操作系统安全实验,包括文件监控、键盘监听、进程隐藏和网络抓包等。教学实践表明,这些实验能够帮助学生加深对Windows内核安全机制的理解,提升系统安全实践能力。
文摘本文在分析进程冻结与恢复所涉及的相关知识点基础上,给出了基于WRK(Windows Research Kernel)实现Windows进程冻结与恢复的技术方案。通过将相关知识点按照相关性和难度分类,设计并实施了一种基于研究性学习法的教学方式,使学生变被动学习为主动学习,提高了综合分析能力和动手能力,取得了满意的教学效果。
文摘作为一门理论与实践并重的课程,《操作系统》在计算机本科教学体系中占有重要的地位。课程的特点是:概念抽象、知识点多、逻辑分散。因此,理论课中学习到的原理、方法、算法,一定要通过实践才能充分的理解和吸收。然而由于操作系统自身的庞大和复杂,一般课程实验多以模拟、测试为主,很少能够真正深入系统内部进行动态观测,大大降低了实验的效果。因此,如何合理的设计操作系统实验一直都是一个具有挑战性的课题。WRK全称"Windows Research Kernel"。
文摘微软在WRK(Windows Research Kernel)中开放了大部分Windows Server 2003的代码,这对高校了解Windows操作系统内核、设计操作系统实验提供了一个很好的基础。但是由于WRK的代码量很大,在缺乏指导的情况下学生很难有效地在WRK上完成操作系统原理实验。本文在分析WRK进程工作集的基础上,设计了三个针对工作集的实验,并给出了实验效果验证方法。
