This book focuses on combining C++ s power and flexibility with high performance and
scalability, resulting in the best of both worlds. Specific topics include temporary objects,
memory management, templates, inheritance, virtual functions, inlining, referencecounting,
STL, and much more
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.
Text mining tries to solve the crisis of information overload by combining techniques from data mining, machine learning, natural language processing, information retrieval, and knowledge management. In addition to providing an in-depth examination of core text mining and link detection algorithms and operations, this book examines advanced pre-processing techniques, knowledge representation considerations, and visualization approaches. Finally, it explores current real-world, mission-critical applications of text mining and link detection in such varied fields as M&A business intelligence, genomics research and counter-terrorism activities.
The makers of handheld medical, industrial and consumerdevices use a wide variety of high resolution, small tomedium sized color TFT LCD displays. The power supplydesigners for these displays must contend with shrinkingboard area, tight schedules, and variations in displaytypes and feature requirements. The LTC®3524 simplifi esthe designer’s job by combining a versatile, easily programmed,TFT LCD bias supply and white LED backlightdriver in a low profi le 4mm × 4mm QFN package.
Piezoelectric motors are used in digital cameras for autofocus,zooming and optical image stabilization. Theyare relatively small, lightweight and effi cient, but theyalso require a complicated driving scheme. Traditionally,this challenge has been met with the use ofseparatecircuits, including a step-up converter and an oversizedgeneric full-bridge drive IC. The resulting high componentcount and large board space are especially problematicin the design of cameras for ever shrinking cell phones.The LT®3572 solves these problems by combining astep-up regulator and a dual full-bridge driver in a 4mm× 4mm QFN package. Figure 1 shows a typical LT3572Piezo motor drive circuit. A step-up converter is usedto generate 30V from a low voltage power source suchas a Li-Ion battery or any input power source within thepart’s wide input voltage range of 2.7V to 10V. The highoutput voltage of the step-up converter, adjustable upto 40V, is available for the drivers at the VOUT pin. Thedrivers operate in a full-bridge fashion, where the OUTAand OUTB pins are the same polarity as the PWMA andPWMB pins, respectively, and the OUTA and OUTB pinsare inverted from PWMA and PWMB, respectively. Thestep-up converter and both Piezo drivers have their ownshutdown control. Figure 2 shows a typical layout
鎖定放大是微弱信號檢測的重要手段。基于相關(guān)檢測理論，利用開關(guān)電容的開關(guān)實現(xiàn)鎖定放大器中乘法器的功能，提出開關(guān)電容和積分器相結(jié)合以實現(xiàn)相關(guān)檢測的方法，并設(shè)計出一種鎖定放大器。該鎖定放大器將微弱信號轉(zhuǎn)化為與之相關(guān)的方波，通過后續(xù)電路得到正比于被測信號的直流電平，為后續(xù)采集處理提供方便。測量數(shù)據(jù)表明鎖定放大器前級可將10-6 A的電流轉(zhuǎn)換為10-1 V的電壓，后級通過帶通濾波器級聯(lián)可將信號放大1×105倍。該方法在降低噪聲的同時，可對微弱信號進行放大，線性度較高、穩(wěn)定性較好。
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.
為了提高傳統(tǒng)溫度控制系統(tǒng)的性能，將PID控制理論與嵌入式系統(tǒng)相結(jié)合，采用瑞薩電子公司的H8S/2166作為核心處理器，AD公司的AD7705以及熱敏電阻溫度傳感器作為溫度檢測單元，利用4×6小鍵盤、LCD顯示器和S1D13305液晶控制器達到良好的人機交互，設(shè)計出了一個應(yīng)用于化工領(lǐng)域的嵌入式實時溫度控制系統(tǒng)。相比于傳統(tǒng)溫度控制系統(tǒng)，該系統(tǒng)提供了更強的計算能力和可擴展能力，采用增量PID控制算法實現(xiàn)復(fù)雜控制。通過實驗，該系統(tǒng)能達到0.1 ℃的溫度控制精度以及小于120 s的溫度穩(wěn)定時間。
Abstract:
In order to improve the performance of conventional temperature control system， combining PID control theory with embedded systems， using the Renesas Electronics Corp. H8S/2166 micro-controller as a core processors， AD7705 and thermistor temperature sensor as a temperature detection unit and 4×6 small keyboard， LCD and S1D13305 LCD controller as a good human-computer interaction， this paper designed an embedded real-time temperature control system which is applied in chemical industry. Compared with conventional temperature control system， this system provides more computing power and extensibility， and adopts PID control algorithm for complex control. Through the experiment， the system can reach temperature control accuracy of 0.1 ℃ and temperature stabilization time of less than 120 seconds.
為了提高環(huán)境參數(shù)采集的自動化水平，提升效率，設(shè)計了無線傳感器系統(tǒng)。本系統(tǒng)運用了傳感器技術(shù)、通信技術(shù)和單片機技術(shù)，實現(xiàn)了對環(huán)境溫度、濕度、光照度以及可燃性氣體濃度等參數(shù)的檢測。它能夠?qū)崟r地與上位機進行無線通信，滿足對環(huán)境參數(shù)實時監(jiān)測的要求。
Abstract:
In order to increase the degree of automation and improve the efficiency of the environment monitoring parameters，the wireless sensor system was developed.combining with the technique of sensor,automatic monitoring，communication and single-chip microcomputer，it realized real-time monitoring environment parameters,such as temperature，humidity，illumination，concentration of com- bustible gas and so on.At the same time it can communicate with upper personal computers，satisfy the desire of real-time monitoring.
