The equal-area theorem●This is sinusoidal PWM (SPWM)●The equal-area theorem can be appliedto realize any shape of waveforms ●Natural sampling●Calculation based on equal-area criterion●Selected harmonic elimination●Regular sampling●Hysteresis-band control●Triangular wave comparison withfeedback control
上传时间： 2013-11-22
上传用户：linyao
The field of microelectromechanical systems (MEMS), particularly micromachinedmechanical transducers, has been expanding over recent years, and the productioncosts of these devices continue to fall. Using materials, fabrication processes, anddesign tools originally developed for the microelectronic circuits industry, newtypes of microengineered device are evolving all the time—many offering numerousadvantages over their traditional counterparts. The electrical properties of siliconhave been well understood for many years, but it is the mechanical properties thathave been exploited in many examples of MEMS. This book may seem slightlyunusual in that it has four editors. However, since we all work together in this fieldwithin the School of Electronics and Computer Science at the University of Southampton,it seemed natural to work together on a project like this. MEMS are nowappearing as part of the syllabus for both undergraduate and postgraduate coursesat many universities, and we hope that this book will complement the teaching thatis taking place in this area.
上传时间： 2013-10-16
上传用户：朗朗乾坤
在研究传统家用燃气报警器的基础上，以ZigBee协议为平台，构建mesh网状网络实现网络化的智能语音报警系统。由于传感器本身的温度和实际环境温度的影响，传感器标定后采用软件补偿方法。为了减少系统费用，前端节点采用半功能节点设备，路由器和协调器采用全功能节点设备，构建mesh网络所形成的家庭内部报警系统，通过通用的电话接口连接到外部的公用电话网络，启动语音模块进行报警。实验结果表明，在2.4 GHz频率下传输，有墙等障碍物的情况下，节点的传输距离大约为35 m，能够满足家庭需要，且系统工作稳定，但在功耗方面仍需进一步改善。 Abstract: On the basis of studying traditional household gas alarm system, this paper proposed the platform for the ZigBee protocol，and constructed mesh network to achieve network-based intelligent voice alarm system. Because of the sensor temperature and the actual environment temperature, this system design used software compensation after calibrating sensor. In order to reduce system cost, semi-functional node devices were used as front-end node, however, full-function devices were used as routers and coordinator，constructed alarm system within the family by building mesh network，connected to the external public telephone network through the common telephone interface, started the voice alarm module. The results indicate that nodes transmit about 35m in the distance in case of walls and other obstacles by 2.4GHz frequency transmission, this is able to meet family needs and work steadily, but still needs further improvement in power consumption.
上传时间： 2013-10-30
上传用户：swaylong
英语句子自然语言处理统计分析例子 Statistical parsing of English sentences Shows how to generate parse trees for English language sentences using a C# port of OpenNLP, a statistical natural language parsing library.
标签： Statistical sentences generate English
上传时间： 2015-04-18
上传用户：fxf126@126.com
A C++ N-grams Package 2.0 This is a simple C++ n-grams package that includes a header, the corresponding cpp file, and a sample driver program. It is a natural language processing tool for creating n-gram profiles for text documents. The details on usage is documented in the header right above each public function defined. This package is based on Dr. Vlado Keselj s Perl package Text::Ngrams which is available in CPAN.
标签： includes correspo N-grams Package
上传时间： 2015-06-12
上传用户：wfl_yy
zemax源码： This DLL models a standard ZEMAX surface type, either plane, sphere, or conic The surface also demonstrates a user-defined apodization filter The filter is defined as part of the real ray trace, case 5 The filter can be used at the stop to produce x-y Gaussian apodization similar to the Gaussian pupil apodization in ZEMAX but separate in x and y. The amplitude apodization is of the form EXP[-(Gx(x/R)^2 + Gy(y/R)^2)] The transmission is of the form EXP[-2(Gx(x/R)^2 + Gy(y/R)^2)] where x^2 + y^2 = r^2 R = semi-diameter The tranmitted intensity is maximum in the center. T is set to 0 if semi-diameter < 1e-10 to avoid division by zero.
标签： standard surface models either
上传时间： 2013-12-05
上传用户：003030
《Prolog Programming in Depth》: In this book, we emphasize practical Prolog programming, not just theory. We present several ready-to-run expert system shells, as well as routines for sorting,searching, natural language processing, and even numerical equation solving. We also emphasize interoperability with other software. For example, Chapter 5 presents techniques for reading Lotus spreadsheets and other special file formats from within a Prolog program.
标签： Prolog Programming programming emphasize
上传时间： 2014-01-24
上传用户：JIUSHICHEN
http://w3eval.calcsharp.net/ W3Eval is Java applet that evaluates mathematical expressions. It uses different approach from conventional calculator, which is more natural to the way people calculate.
标签： mathematical expressions calcsharp evaluates
上传时间： 2013-12-13
上传用户：youke111
This paper presents an interactive technique that produces static hairstyles by generating individual hair strands of the desired shape and color, subject to the presence of gravity and collisions. A variety of hairstyles can be generated by adjusting the wisp parameters, while the deformation is solved efficiently, accounting for the effects of gravity and collisions. Wisps are generated employing statistical approaches. As for hair deformation, we propose a method which is based on physical simulation concepts but is simplified to efficiently solve the static shape of hair. On top of the statistical wisp model and the deformation solver, a constraint-based styler is proposed to model artificial features that oppose the natural flow of hair under gravity and hair elasticity, such as a hairpin. Our technique spans a wider range of human hairstyles than previously proposed methods, and the styles generated by this technique are fairly realistic.
标签： interactive hairstyles generating technique
上传时间： 2013-12-20
上传用户：sssl
The Joint Video Team (JVT) of ISO/IEC MPEG and ITU-T VCEG are finalising a new standard for the coding (compression) of natural video images. The new standard [1] will be known as H.264 and also MPEG-4 Part 10, “Advanced Video Coding”. This document describes the methods of filtering reconstructed blocks in an H.264 CODEC. Note that the H.264 draft standard is not yet finalised and so readers are encouraged to refer to the latest version of the standard.
标签： finalising standard Joint ITU-T
上传时间： 2015-12-08
上传用户：fanboynet
