We address the problem of predicting a word from previous words in a sample of text. In particular, we discuss n-gram models based on classes of words. We also discuss several statistical algorithms for assigning words to classes based on the frequency of their co-occurrence with other words. We find that we are able to extract classes that have the flavor of either syntactically based groupings or semantically based groupings, depending on the nature of the underlying statistics.
标签: predicting particular previous address
上传时间: 2016-12-26
上传用户:xfbs821
Huffman codes In telecommunication, how do we represent a set of messages, each with an access frequency, by a sequence of 0’s and 1’s? To minimize the transmission and decoding costs, we may use short strings to represent more frequently used messages. This problem can by solved by using an extended binary tree which is used in the 2- way merging problem.
标签: telecommunication represent messages Huffman
上传时间: 2014-01-04
上传用户:x4587
CDMA 的仿真程序,Frequency Hopping Spread Spectrum,Random frequency hopps to form a spread signal
上传时间: 2013-12-22
上传用户:nanshan
This is GPS Acquisition..by Matlab, this file performs cold start acquisition on the collected "data". It searches for GPS signals of all satellites, which are listed in field "acqSatelliteList" in the settings structure. Function saves code phase and frequency of the detected signals in the "acqResults" structure.
标签: Acquisition acquisition collected performs
上传时间: 2013-12-28
上传用户:wxhwjf
This is GPS Matlab acquisition code. Function performs cold start acquisition on the collected "data". It searches for GPS signals of all satellites, which are listed in field "acqSatelliteList" in the settings structure. Function saves code phase and frequency of the detected signals in the "acqResults" structure.
标签: acquisition collected Function performs
上传时间: 2014-08-07
上传用户:xjz632
Enhanced version of the Serial Peripheral Interface available on Motorola s MC68HC11 family of CPUs.Enhancements include a wider supported operating frequency range, 4deep read and write fifos, and programmable transfer count dependent interrupt generation. As with the SPI found in MC68HC11 processors the core features programmable clock phase [CPHA] and clock polarity [CPOL]. The core features an 8bit wishbone interface. Very simple, very small.
标签: Peripheral Interface available Enhanced
上传时间: 2014-12-06
上传用户:invtnewer
The Window Design Method The basic idea behind the design of linear-phase FIR filters using the window method is to choose a proper ideal frequency-selective filter [which always has a noncausal, infinite duration impulse response] and then truncate its impulse response hd[n] to obtain a linear-phase and causal FIR filter h[n]. To truncate the impulse response of the ideal filter a time window w[n] is used. Available windows in Matlab are rectangular [or boxcar in Matlab], bartlett, hamming, hanning
标签: linear-phase The the filters
上传时间: 2017-03-20
上传用户:PresidentHuang
We obtained the energy transport velocity distribution for a three dimensional ideal cloak explicitly. Near the operation frequency, the energy transport velocity has rather peculiar distribution. The velocity along a line joining the origin of the cloak is a constant, while the velocity approaches zero at the inner boundary of the cloak. A ray pointing right into the origin of the cloak will experience abrupt changes of velocities when it impinges on the inner surface of the cloak. This peculiar distribution causes long time delays for beams passing through the ideal cloak within a geometric optics description.
标签: distribution dimensional transport obtained
上传时间: 2013-12-19
上传用户:zhliu007
SPWM technique for Three Phase Inverter. Analysis fundamental improvement with respect to modulation index variation is done in simulation. Analysis can be done also for switching frequency variation for shifting the dominant harmonics
标签: fundamental improvement modulation technique
上传时间: 2017-04-23
上传用户:hanli8870
Servomotors are available as AC or DC motors. Early servomotors were generally DC motors because the only type of control for large currents was through SCRs for many years. As transistors became capable of controlling larger currents and switching the large currents at higher frequencies, the AC servomotor became used more often. Early servomotors were specifically designed for servo amplifiers. Today a class of motors is designed for applica-tions that may use a servo amplifier or a variable-frequency controller, which means that a motor may be used in a servo system in one application, and used in a variable-frequency drive in another application. Some companies also call any closed-loop system that does not use a stepper motor a servo system, so it is possible for a simple AC induction motor that is connected to a velocity controller to be called a servomotor.
标签: motors Servomotors servomotors available
上传时间: 2014-08-10
上传用户:源码3