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 78 毫秒
1.
为了研究时间交织流水线ADC的结构和性能,提出了一种完全在Matlab自带的Simulink仿真环境下对时间交织流水线ADC进行高层次行为级建模和仿真的方法.在完整掌握了该类型AD转换器整体结构的基础上,对各个基本模块进行了Matlab数学建模,并最终完成了一个四通道、1.5bit/stage、采用数字校正技术的10位分辨率时间交织流水线AD转换器.最后还给出了ADC动、静态性能的测试方法并在Simulink仿真环境下对其进行了仿真测试,结果表明这种高层次的仿真方法具有高效、准确的优点,大大提高了AD转换器电路的设计效率.  相似文献   

2.
一个新的MOS模拟单元电路版图的STACK生成方法   总被引:1,自引:0,他引:1  
提出了一种新的MOS模拟单元电路的STACK版图自动生成方法。该方法将电路网表映射为扩散图,基于扩散图进行电路划分、模板匹配和对称查找。提出的对称查找算法适用于非全对称电路的最大匹配对称结构查找。文中改进了Atallah欧拉路径生成算法,通过增加哑元条保证欧拉路 径的生成。对生成的STACK,采用分布式寄生电容模型计算各个节点的寄生电容,并计算STACK的面积和形状,以确保其能够满足设计要求。  相似文献   

3.
针对降落伞折叠展开数值模拟中需要解决的降落伞多层折叠建模这一关键技术问题,根据降落伞折叠的特点,提出一种采用初始矩阵方法修正直接折叠模型的方法.该方法采用单元坐标空间转换实现直接折叠建模,通过映射关系将映射网格和参考网格间差异作为初始位移施加在映射网格上,从而对直接折叠产生的初始单元误差进行修正,以解决由于初始单元误差造成计算结果不准确的问题.最后以某模型降落伞为例进行了降落伞的多层“Z”型折叠建模,通过计算对比和风洞实验证明了文中方法的可行性和合理性;该方法不仅可以解决降落伞折叠建模问题,对其他柔性织物体积压缩比大的折叠建模也有一定的指导作用.  相似文献   

4.
提出一种模拟电路行为级自动建模的方法.通过构建节点代数方程确定系统结构描述,利用小波配置方法建立所有基本单元的行为级描述,最终建立系统行为级模型,并据此开发了自动建模软件.所建模型面向模拟电路硬件描述语言的工业标准形式,在保证较高精度的同时,在仿真速度上与晶体管级描述相比具有明显的优势.  相似文献   

5.
多维函数的进化逼近   总被引:4,自引:0,他引:4  
提出一种多维函数的通用进化逼近方法,通过构造一类结合采样九样条函数优点的基本函数优点的基本函数族,提出一种单调函数逼近方法,并借助采样函数的有界变差特点,将该方法推广到一般函数情形,这两种函数的逼近都可通过遗传算法完成,该方法的优点在于可以简单一致地推广到更高维函数的逼近,并使逼近复杂度与维数成线性关系,降低学习算法难度,试验表明,方法是有效的,基于文中单调函数逼近技术提出的一种新的决策策略学习方  相似文献   

6.
在基于模糊G均值(FCM)聚类的模糊建模和神经模糊建模中,模糊聚类数是一个非常重要的参数,其决定了模型结构的复杂程度.本文提出了基于误差回溯的启发式模糊聚类学习方法.在建模过程中,该方法可以从较小的聚类数开始,根据误差检测,逐步填补输入聚类空间的"空洞",从而获得合适的模型规则数.函数逼近和非线性动态系统建模实验结果表明这种方法是简便而有效的.  相似文献   

7.
从提高神经网络泛化能力的角度提出一种改进方法.利用Taylor级数展开的思想,用线性和非线性组合构成函数映射关系,即改进的神经网络是用原神经网络的非线性映射和关于输入信号的线性映射的和来逼近期望值.文中还给出了该神经网络学习速率的自适应调节方法.对线性对象和非线性对象分别进行建模仿真,结果表明,改进的神经网络比基于正则化方法的神经网络具有更好的泛化能力.  相似文献   

8.
本文介绍一个基于模糊神经网络的数据逼近和泛化建模方法,定义了一种模糊系统动态调节神经网络的学习率,给出了用迭代自组织数据分析算法确定神经网络结构、初始化神经网络参数的方法.在雷达天线罩视线误差建模中的应用表明,这种方法加快了网络的收敛速度,避免了局部极值,具有较高的数据逼近和泛化能力.  相似文献   

9.
分值函数估计的准确性是影响自然梯度盲分离算法收敛速度和稳定性的一个重要因素.提出了一种通过函数逼近直接估计分值函数的方法.用一组正交多项式的线性组合来逼近分值函数,其性能用均方误差来衡量.线性组合的系数向量可运用分值函数的性质,通过最小化均方误差自适应学习得到.将估计到的分值函数代入自然梯度迭代公式中就得到新算法.实验...  相似文献   

10.
为避免使用函数逼近器(神经网络或模糊系统),并提高双惯量伺服系统的瞬态响应和稳态性能,针对含外部扰动的双惯量伺服系统,提出一种基于预设性能函数(Prescribed performance function, PPF)的类比例状态反馈控制策略.首先,提出一种改进的带有最大超调、收敛速率以及稳态误差的预设性能函数,并将该函数融入控制器设计使二惯量伺服的跟踪误差保持在预定的边界之内.其次,基于预设性能函数设计了类比例状态反馈控制器实现跟踪控制.与传统基于函数逼近控制方法相比较,该方法可降低控制系统计算复杂度同时消除反演控制中存在的复杂度爆炸问题.最后,利用双惯量伺服系统实验平台开展了对比实验,验证了所提出方法的有效性.  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.  相似文献   

18.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

19.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

20.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  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