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91.
基于MatLab环境的高等数学可视化 总被引:2,自引:0,他引:2
将高等数学与计算机(MatLab工具)结合起来,利用现代科技手段,动态演示高等数学的抽象问题,使高等数学理论、概念不再抽象难懂,提高学生运用先进的数学工具学习高等数学的能力,且有利于培养学生学习数学的兴趣和数学应用意识。 相似文献
92.
如何将多媒体技术有效地应用于经济数学课堂教学中,是目前经济数学教学改革值得注意的问题。结合教学实践,分析当前经济数学多媒体教学存在的问题,提出经济数学课程使用多媒体教学必须结合课程的特点,教学的需要以及学生的实际情况,将传统黑板教学与多媒体教学优势互补,以实现最佳教学效果。 相似文献
93.
在高等数学的教学过程中,把抽象的数学问题与科学计算软件适当结合,有利于培养学生学习数学的兴趣和应用数学理论解决实际问题的意识。同时对增强教学效果、提高教育质量、促进教学改革等方面都是有积极作用。从分析以Matlab软件为代表的科学计算软件在高等数学教学中的作用着手,辅以在教学中学生不易理解的典型实例进一步阐明。同时,根据在教学实践中发现的问题,分析了如果对科学计算软件使用不当会带来的消极影响。 相似文献
94.
陈依鹏 《计算机光盘软件与应用》2011,(20)
随着现代信息社会对通信业务要求的不断增长,图像通信与通信容量的矛盾日益突出。为了缓解网络带宽的不足、加快图像信息的传播速度,对于基于高比率的图像压缩算法的研究很有必要。目前比较流行的多级树集合分裂算法压缩效果比较好,输出的比特流较少,但是需要对内存中的数据反复的读取,且反复的在链表结构中扫描不重要系数,增加内存的负担及软硬件实现的复杂度,从而降低了编码的效率。本文针对多级树集合分裂算法的缺点提出了一种基于离散小波变换的改进的多级树集合分裂算法,通过对小波系数排序过程的调整,减少了对内存反复的读取操作,减轻了对内存造成的负担,提高了编码的效率。 相似文献
95.
一种MIMO-OFDM系统的信道估计算法 总被引:1,自引:1,他引:0
导频辅助的最小平方(LS)算法是MIMO—OFDM系统中常用的信道估计方法,特点是易于实现,但精度不高。基于最小均方误差(MMSE)的信道估计算法性能较好,但复杂度高,难以实现。提出了一种基于离散傅里叶变换(DFT)的信道估计算法,首先将LS信道估计循环前缀长度以外的时域响应值置零,然后选择重要路径,再通过计算参考导频的相位偏移量来进行补偿,最终实现信道的估计。算法能够满足一定的估计精度,且便于实现。仿真数据证明了算法的有效性。 相似文献
96.
We observe that successive applications of known results from the theory of positive systems lead to an efficient general algorithm for positive realizations of transfer functions. We give two examples to illustrate the algorithm, one of which complements an earlier result of [L. Benvenuti, L. Farina, An example of how positivity may force realizations of ‘large’ dimensions, Systems Control Lett. 36 (1999) 261–266]. Finally, we improve a lower-bound of [B. Nagy, M. Matolcsi, A lower-bound on the dimension of positive realizations, IEEE Trans. Circuits Syst. I 50 (2003) 782–784] to indicate that the algorithm is indeed efficient in general. 相似文献
97.
Dimas?Martínez?MoreraEmail author Paulo?Cezar?Carvalho Luiz?Velho 《The Visual computer》2008,24(12):1025-1037
This paper discusses the problem of modeling on triangulated surfaces with geodesic curves. In the first part of the paper
we define a new class of curves, called geodesic Bézier curves, that are suitable for modeling on manifold triangulations. As a natural generalization of Bézier curves, the new curves
are as smooth as possible. In the second part we discuss the construction of C
0 and C
1 piecewise Bézier splines. We also describe how to perform editing operations, such as trimming, using these curves. Special
care is taken to achieve interactive rates for modeling tasks. The third part is devoted to the definition and study of convex
sets on triangulated surfaces. We derive the convex hull property of geodesic Bézier curves.
相似文献
Luiz VelhoEmail: |
98.
Plant floor material handling is a loose loop in most assembly plants. Simulation offers a quick, controllable and tunable approach for prototyping complex material handling processes in manufacturing environments. This paper proposes a hybrid simulation approach, using both discrete event and agent-based technologies, to model complex material handling processes in an assembly line. A prototype system is implemented using a commercial multi-paradigm modeling tool. In this prototype, JIT principles are applied to both the production and the material handling processes. The system performance is evaluated and system optimization directions are suggested. The proposed hybrid modeling approach facilitates the implementation of a responsive and adaptive environment in that various “what-if” scenarios can be simulated under different simulation configurations and real-time situations. 相似文献
99.
Mehdi Ghatee S. Mehdi Hashemi Behnam Hashemi Mehdi Dehghan 《Computers & Mathematics with Applications》2008,55(12):2767-2790
Duality properties have been investigated by many researchers in the recent literature. They are introduced in this paper for a fully fuzzified version of the minimal cost flow problem, which is a basic model in network flow theory. This model illustrates the least cost of the shipment of a commodity through a capacitated network in terms of the imprecisely known available supplies at certain nodes which should be transmitted to fulfil uncertain demands at other nodes. First, we review on the most valuable results on fuzzy duality concepts to facilitate the discussion of this paper. By applying Hukuhara’s difference, approximated and exact multiplication and Wu’s scalar production, we exhibit the flow in network models. Then, we use combinatorial algorithms on a reduced problem which is derived from fully fuzzified MCFP to acquire fuzzy optimal flows. To give duality theorems, we utilize a total order on fuzzy numbers due to the level of risk and realize optimality conditions for providing some efficient combinatorial algorithms. Finally, we compare our results with the previous worthwhile works to demonstrate the efficiency and power of our scheme and the reasonability of our solutions in actual decision-making problems. 相似文献
100.
This paper addresses the problem of fault detection and isolation for a particular class of discrete event dynamical systems
called hierarchical finite state machines (HFSMs). A new version of the property of diagnosability for discrete event systems
tailored to HFSMs is introduced. This notion, called L1-diagnosability, captures the possibility of detecting an unobservable fault event using only high level observations of the
behavior of an HFSM. Algorithms for testing L1-diagnosability are presented. In addition, new methodologies are presented for studying the diagnosability properties of
HFSMs that are not L1-diagnosable. These methodologies avoid the complete expansion of an HFSM into its corresponding flat automaton by focusing
the expansion on problematic indeterminate cycles only in the associated extended diagnoser.
Andrea Paoli received the master degree in Computer Science Engineering and the Ph.D. in Automatic Control and Operational Research from the University of Bologna in 2000 and 2003 respectively. He currently holds a Post Doc position at the Department of Electronics, Computer Science and Systems (DEIS) at the University of Bologna, Italy. He is a member of the Center for Research on Complex Automated Systems (CASY) Giuseppe Evangelisti. From August to January 2002, and in March 2005 he held visiting positions at the Department of Electrical Engineering and Computer Science at The University of Michigan, Ann Arbor. In July 2005 he won the prize IFAC Outstanding AUTOMATICA application paper award for years 2002-2005 for the article by Claudio Bonivento, Alberto Isidori, Lorenzo Marconi, Andrea Paoli titled Implicit fault-tolerant control: application to induction motors appeared on AUTOMATICA issue 30(4). Since 2006 he is a member of the IFAC Technical Committee on Fault Detection, Supervision and Safety of Technical Processes (IFAC SAFEPROCESS TC). His current research interests focus on Fault Tolerant Control and Fault Diagnosis in distributed systems and in discrete event systems and on industrial automation software architectures following an agent based approach. His theoretical background includes also nonlinear control and output regulation using geometric approach. Stéphane Lafortune received the B. Eng degree from Ecole Polytechnique de Montréal in 1980, the M. Eng. degree from McGill University in 1982, and the Ph.D. degree from the University of California at Berkeley in 1986, all in electrical engineering. Since September 1986, he has been with the University of Michigan, Ann Arbor, where he is a Professor of Electrical Engineering and Computer Science. Dr. Lafortune is a Fellow of the IEEE (1999). He received the Presidential Young Investigator Award from the National Science Foundation in 1990 and the George S. Axelby Outstanding Paper Award from the Control Systems Society of the IEEE in 1994 (for a paper co-authored with S. L. Chung and F. Lin) and in 2001 (for a paper co-authored with G. Barrett). At the University of Michigan, he received the EECS Department Research Excellence Award in 1994–1995, the EECS Department Teaching Excellence Award in 1997–1998, and the EECS Outstanding Achievement Award in 2003–2004. Dr. Lafortune is a member of the editorial boards of the Journal of Discrete Event Dynamic Systems: Theory and Applications and of the International Journal of Control. His research interests are in discrete event systems modeling, diagnosis, control, and optimization. He is co-developer of the software packages DESUMA and UMDES. He co-authored, with C. Cassandras, the textbook Introduction to Discrete Event Systems—Second Edition (Springer, 2007). Recent publications and software tools are available at the Web site . 相似文献
Stéphane LafortuneEmail: |
Andrea Paoli received the master degree in Computer Science Engineering and the Ph.D. in Automatic Control and Operational Research from the University of Bologna in 2000 and 2003 respectively. He currently holds a Post Doc position at the Department of Electronics, Computer Science and Systems (DEIS) at the University of Bologna, Italy. He is a member of the Center for Research on Complex Automated Systems (CASY) Giuseppe Evangelisti. From August to January 2002, and in March 2005 he held visiting positions at the Department of Electrical Engineering and Computer Science at The University of Michigan, Ann Arbor. In July 2005 he won the prize IFAC Outstanding AUTOMATICA application paper award for years 2002-2005 for the article by Claudio Bonivento, Alberto Isidori, Lorenzo Marconi, Andrea Paoli titled Implicit fault-tolerant control: application to induction motors appeared on AUTOMATICA issue 30(4). Since 2006 he is a member of the IFAC Technical Committee on Fault Detection, Supervision and Safety of Technical Processes (IFAC SAFEPROCESS TC). His current research interests focus on Fault Tolerant Control and Fault Diagnosis in distributed systems and in discrete event systems and on industrial automation software architectures following an agent based approach. His theoretical background includes also nonlinear control and output regulation using geometric approach. Stéphane Lafortune received the B. Eng degree from Ecole Polytechnique de Montréal in 1980, the M. Eng. degree from McGill University in 1982, and the Ph.D. degree from the University of California at Berkeley in 1986, all in electrical engineering. Since September 1986, he has been with the University of Michigan, Ann Arbor, where he is a Professor of Electrical Engineering and Computer Science. Dr. Lafortune is a Fellow of the IEEE (1999). He received the Presidential Young Investigator Award from the National Science Foundation in 1990 and the George S. Axelby Outstanding Paper Award from the Control Systems Society of the IEEE in 1994 (for a paper co-authored with S. L. Chung and F. Lin) and in 2001 (for a paper co-authored with G. Barrett). At the University of Michigan, he received the EECS Department Research Excellence Award in 1994–1995, the EECS Department Teaching Excellence Award in 1997–1998, and the EECS Outstanding Achievement Award in 2003–2004. Dr. Lafortune is a member of the editorial boards of the Journal of Discrete Event Dynamic Systems: Theory and Applications and of the International Journal of Control. His research interests are in discrete event systems modeling, diagnosis, control, and optimization. He is co-developer of the software packages DESUMA and UMDES. He co-authored, with C. Cassandras, the textbook Introduction to Discrete Event Systems—Second Edition (Springer, 2007). Recent publications and software tools are available at the Web site . 相似文献