在Weak环境下的knn算法开发 具体需要的说明都在文件包中
上传时间： 2014-01-11
上传用户：sxdtlqqjl
Boosting is a meta-learning approach that aims at combining an ensemble of Weak classifiers to form a strong classifier. Adaptive Boosting (Adaboost) implements this idea as a greedy search for a linear combination of classifiers by overweighting the examples that are misclassified by each classifier. icsiboost implements Adaboost over stumps (one-level decision trees) on discrete and continuous attributes (words and real values). See http://en.wikipedia.org/wiki/AdaBoost and the papers by Y. Freund and R. Schapire for more details [1]. This approach is one of most efficient and simple to combine continuous and nominal values. Our implementation is aimed at allowing training from millions of examples by hundreds of features in a reasonable time/memory.
标签： meta-learning classifiers combining Boosting
上传时间： 2016-01-29
上传用户：songnanhua
AdaBoost is an efficient tool in machine learning. It can combine a series of Weak learners into a strong learner. Besides pattern classification, it also can be applied into feature selection. This document explains the use of AdaBoost.
标签： efficient AdaBoost learning learners
上传时间： 2013-12-06
上传用户：小宝爱考拉
Passion is sweet Love makes Weak You said you cherised freedom so You refused to let it go Follow your faith Love and hate never failed to seize the day Don t give yourself away Oh when the night
标签： You cherised Passion freedom
上传时间： 2014-12-01
上传用户：电子世界
it is an adaboost Weak learner
上传时间： 2013-12-21
上传用户：gtf1207
Many applications have required the positioning accuracy of a Global Navigation Satellite System (GNSS). Some applications exist in environments that attenuate GNSS signals, and, consequently, the received GNSS signals become very Weak. Examplesofsuchapplicationsarewirelessdevicepositioning,positioninginsensor networks that detect natural disasters, and orbit determination of geostationary and high earth orbit (HEO) satellites. Conventional GNSS receivers are not designed to work with Weak signals. This book presents novel GNSS receiver algorithms that are designed to work with very Weak signals.
标签： Receivers Signals GNSS Weak for
上传时间： 2020-06-09
上传用户：shancjb
微弱信号检测装置 四川理工学院 刘鹏飞、梁天德、曾学明 摘要： 本设计以TI的Launch Pad为核心板，采用锁相放大技术设计并制作了一套微弱信号检测装置，用以检测在强噪声背景下已知频率微弱正弦波信号的幅度值，并在液晶屏上数字显示出所测信号相应的幅度值。实验结果显示其抗干扰能力强，测量精度高。 关键词：强噪声；微弱信号；锁相放大；Launch Pad Abstract: This design is based on the Launch Pad of TI core board, using a lock-in amplifier technique designed and produced a Weak signal detection device, to measure the known frequency sine wave signal amplitude values of the Weak in the high noise background, and shows the measured signal amplitude of the corresponding value in the liquid crystal screen. Test results showed that it has high accuracy and strong anti-jamming capability. Keywords: Weak signal detection; lock-in-amplifier; Launch Pad 1、引言 随着现代科学技术的发展，在科研与生产过程中人们越来越需要从复杂高强度的噪声中检测出有用的微弱信号，因此对微弱信号的检测成为当前科研的热点。微弱信号并不意味着信号幅度小，而是指被噪声淹没的信号，“微弱”也仅是相对于噪声而言的。只有在有效抑制噪声的条件下有选择的放大微弱信号的幅度，才能提取出有用信号。微弱信号检测技术的应用相当广泛，在生物医学、光学、电学、材料科学等相关领域显得愈发重要。 2、方案论证 针对微弱信号的检测的方法有很多，比如滤波法、取样积分器、锁相放大器等。下面就针对这几种方法做一简要说明。 方案一：滤波法。 在大部分的检测仪器中都要用到滤波方法对模拟信号进行一定的处理，例如隔离直流分量，改善信号波形，防止离散化时的波形混叠，克服噪声的不利影响，提高信噪比等。常用的噪声滤波器有：带通、带阻、高通、低通等。但是滤波方法检测信号不能用于信号频谱与噪声频谱重叠的情况，有其局限性。虽然可以对滤波器的通频带进行调节，但其噪声抑制能力有限，同时其准确性与稳定性将大打折扣。
上传时间： 2013-11-04
上传用户：lty6899826
锁定放大是微弱信号检测的重要手段。基于相关检测理论，利用开关电容的开关实现锁定放大器中乘法器的功能，提出开关电容和积分器相结合以实现相关检测的方法，并设计出一种锁定放大器。该锁定放大器将微弱信号转化为与之相关的方波，通过后续电路得到正比于被测信号的直流电平，为后续采集处理提供方便。测量数据表明锁定放大器前级可将10-6 A的电流转换为10-1 V的电压，后级通过带通滤波器级联可将信号放大1×105倍。该方法在降低噪声的同时，可对微弱信号进行放大，线性度较高、稳定性较好。 Abstract: Lock-in Amplifying（LIA）is one of important means for Weak signal detection. Based on cross-correlation detection theory， switch in the swithched capacitor was used as multiplier of LIA， and a new method of correlation detection was proposed combining swithched capacitor with integrator. A kind of LIA was designed which can convert the Weak signal to square-wave， then DC proportional to measured signal was obtained through follow-up conditioning circuit， providing convenience for signal acquisition and processing. The measured data shows that the electric current（10-6 A） can be changed into voltage（10-1 V） by LIA， and the signal is magnified 1×105 times by cascade band-pass filter. The noise is suppressed and the Weak signal is amplified. It has the advantages of good linearity and stability.
上传时间： 2013-11-28
上传用户：黑漆漆
为提高电容测量精度，针对电容式传感器的工作原理设计了基于PIC16LF874单片机电容测量模块。简单阐述了电容测量电路的应用背景和国内外研究现状，介绍了美国Microchip公司PIC16LF874单片机的特性。电容式传感器输出的动态微弱电容信号通过PS021型电容数字转换器把模拟量数据转换成数字量数据，所测数据由PIC16LF874单片机应用程序进行处理、显示和保存。实验结果表明，固定电容标称值为10~20 pF 的测量值相对误差在1%以内，同时也可知被测电容容值越大，测量值和标称值相对误差越小。 Abstract: To improve the accuracy of capacitance measurement，aimed at the principle of work of mercury capacitance acceleration transducer，the design of micro capacitance measurement circuit is based on the key PIC16LF874 chip. Briefly discusses the application of the capacitance measuring circuit for the background and status of foreign researchers，focusing on the United States PIC16LF874 microcontroller features. Capacitive sensor outputed signal through the dynamics of Weak PS021-chip capacitors （capacitancedigital converter） to convert analog data into digital data，the measured data from the PIC16LF874 microcontroller application process， display and preservation. Experimental results show that the fixed capacitor 10pF ~ 20pF nominal value of the measured value of relative error is within 1%，but also it canbe seen the value of the measured capacitance larger，measuring value and the nominal value of relative error smaller.
上传时间： 2013-10-29
上传用户：wojiaohs
Kismet is an 802.11b network sniffer and network dissector. It is capable of sniffing using most wireless cards, automatic network IP block detection via UDP, ARP, and DHCP packets, Cisco equipment lists via Cisco Discovery Protocol, Weak cryptographic packet logging, and Ethereal and tcpdump compatible packet dump files. It also includes the ability to plot detected networks and estimated network ranges on downloaded maps or user supplied image files. Kismet是一个针对IEEE802.11b无线局域网的嗅探和包分析器，支持大多数无线网卡，支持自动检测UDP、ARP和DHCP的数据包，支持通过CDP协议检测思科网络设备，支持加密数据包记录，采用与Ethereal和Tcpdump兼容的的数据包记录文件，支持通过用户提供地图来检测和评估无线网络范围。
标签： network dissector sniffing capable
上传时间： 2014-11-25
上传用户：wweqas
