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Nonlinear compensation research and simulation of.bandlimited QPSK digital satellite channels

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Journal of.Harbin Institute of.Technology(New Series) 2000年第1期7卷 46-49页

作者：何茂平顾学迈 dept. of.ece Harbin Institute of Technology Harbin 150001 China

Presents a phase compensation against the signal distortion mainly caused by TWTA to solve the problem of.compensation and modelling of.a nonlinear QPSK satellite channel assumed to be bandlimited and exhibit both amplitude and phase nonlinearities, and to lower the bit error probability of.nonlinear channel, and concludes with simulation results that the compensation against phase distortion of.TWTA can significantly improve the nonlinear performance of.the channel.

关键词： QPSK satellite channel nonlinearity phase compensation

A Multi-Channel CMOS Analog Front-End Interface IC with 157.8 d B Current Detection Dynamic Range

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Chinese Journal of.Electronics 2024年第2期33卷 393-402页

作者： Kunyu WANG Wenjing XU Chengbin ZHANG Yanjun YANG Man-Kay LAW Li ZHOU Jie CHEN Ming CHEN Institute of.Microelectronics of.the Chinese Academy of.Science University of.Chinese Academy of.Sciences Zunyi Normal University Institute of.Microelectronics and dept.of.ece FST University of Macau

A high dynamic range and low-noise CMOS(complementary metal-oxide-semiconductor transistor)front-end interface integrated circuit(IC) with multi-channel detection is presented in this paper. Two different current detection channels, composed of.a trans-impedance amplifier(TIA) and an integrator-differentiator TIA, are used to boost the current detection range. A capacitance-coupled instrument amplifier(CCIA) is also included to realize high precision voltage detection. A fourth-order sigma-delta modulator using a second-order loop filter and a second-order noise shaping integral quantizer is adopted to realize effective number of.bits above 16 bits. The presented interface IC is implemented in 0.18-μm CMOS process with supply voltage of.3.3 V, and a proto-type electrochemical sensor platform with miniaturized sensor array is developed to verify the functionality of.the interface IC. Measurement results indicate that the designed interface IC achieves 157.8 d B current detection dynamic range, and the measured input-referred current noise and voltage noise floor are 1.04 p A and 58.4 n V within 10 k Hz integration bandwidths,respectively.

关键词： Integrated circuits Sigma-delta modulation Semiconductor device measurement Voltage measurement Current measurement Noise Bandwidth

An Application of.Hierarchical Hybrid Control Theory to Automotive Powertrain Systems

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An Application of Hierarchical Hybrid Control Theory to Auto...

The Study of.the Grit-blasting Parameters and Their Effects on the Adhesive Strength of.the Plasma Sprayed Coatings

第十九届中国控制会议

作者： Peter E．Caines M．Shahid Shaikh dept. ece McGill University MontréalQCCanada H3A 2A7 dept. ece McGill University MontréalQCCanada H3A 2A7

＜正＞The notion of.state aggregation via the dynamical consistency relation and the resulting abstractions of.dynamical systems were originally developed by Caines and Wei [9] and then extended by Lemch and Caines [12, 6, 7] to the case of.hybrid systems. In this paper, the theory of.hybrid systems and the theory of.state aggregated hierarchical hybrid systems are used as a framework for an initial formulation of.sub-optimal control strategies for automatic automotive powertrain （i.e. engine and transmission） systems under cruise control.

关键词： Hierarchical hybrid systems Automotive powertrain control Automobile cruise control Optimal control.

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厦门大学学报（自然科学版） 2002年第S1期41卷 108-109页

作者： M Heydarzadeh Sohi M Frooghieh Sh Khameneh Asl dept. of.Metallurgy and Materials Engineering Faculty of.Engineering University of TehranDept. of Metallurgy and Materials Engineering Faculty of EngineeringUniversity of TehranDept. of Metallurgy and Materials Engineering Faculty of Engineering University of Tehran IranIranIran

Surface Preparation is very important in adhesive b on ding of.spray coatings to the surface of.a work piece. The common practice is gr it-blasting of.the surface before subjecting it to the spray coating process. In this study, grit-blasting of.an AISI 4130 steel (of.different heat treatmen ts) with Al 2O 3 particles was studied. Various grit-blasting parameters such as blasting particle size, the distance between blasting nozzle and the work pi ece (25, 30 and 40 cm.), blasting pressure (3,4,5,6 and 7 bars), blasting time ( 3, 6 and 10 seconds), and the blasting angle (45° and 90°) were examined in or der to find the optimum roughness. The mean roughness (Ra) of.the grit-blasted surfaces were measured and the vari ations of.the roughness with respect to the above mentioned variables were studi ed. The results show that by increasing blasting time, surface roughness increas es up to a maximum and then slightly decreases it with further duration of.t he process. On the other hand a lengthy blasting causes some undesirable results such as an increase in residual particles between surface irregularities. There fore an optimum blasting time is of.great importance. Increasing the blasting pr essure also provides a rougher surface, but in grit blasting of.harder specimens the surface roughness decreases when the pressure reaches a certain limit. About the blasting angle, it was noticed that an angle of.45° results in less r esidual particles between the surface irregularities, in comparison to the angle of.90°. After grit-blasting, the specimens were plasma spray coated with 80% ZrO 2-20 % Y 2O 3 powder. The adhesive strength of.the coating to the substrate was the n measured according to the DIN 50160 standard. The results show that for a certain base metal, the adhesive strength is directl y related to the surface roughness of.the base material. Residual particles afte r grit-blasting the surface of.the specimens can also have a strong deteriorati ng effect on adhesive

关键词： The Study of.the Grit-blasting Parameters and Their Effects on the Adhesive Strength of.the Plasma Sprayed Coatings

Automatic Detection and Classification of.Insects Using Hybrid FF-GWO-CNN Algorithm

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Intelligent Automation & Sof. Computing 2023年第5期36卷 1881-1898页

作者： B.Divya M.Santhi Department of.ece Saranathan College of EngineeringTrichyIndia

Pest detection in agricultural cropﬁelds is the most challenging task,so an effective pest detection technique is required to detect insects *** processing techniques are widely preferred in agricultural science because they of.er multiple advantages like maximal crop protection,improved crop man-agement and *** the other hand,developing the automatic pest mon-itoring system dramatically reduces the workforce and *** image processing approaches are limited due to the disadvantages like poor efﬁciency and less ***,a successful image processing technique based on FF-GWO-CNN classiﬁcation algorithm is introduced for effective pest monitor-ing and *** four-step image processing technique begins with image pre-processing,removing the insect image’s noise and sunlight illumination by utilizing an adaptive medianﬁ*** insects’size and shape are identiﬁed using the Expectation Maximization Algorithm(EMA)based clustering technique,which involves not only clustering the data but also uncovering the correlations by visualizing the global shape of.an *** up robust feature(SURF)method is employed to select the best possible image ***,the image with best features is classiﬁed by introducing a hybrid FF-GWO-CNN algorithm,which combines the beneﬁts of.Fireﬂy(FF),Grey Wolf Optimization(GWO)and Convolutional Neural Network(CNN)classiﬁcation algorithm for enhancing the classiﬁcation *** entire work is executed in MATLAB simulation *** test result reveals that the suggested technique has deliv-ered optimal performance with high accuracy of.97.5%,precision of.94%,recall of.92%and F-score value of.92%.

关键词： Adaptive medianﬁlter EMA SURF FF algorithm GWO CNN

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FD-MIMO距离高分辨雷达及其旁瓣抑制

电子与信息学报 2008年第9期30卷 2033-2037页

作者：戴喜增许稼彭应宁夏香根清华大学电子工程系北京100084 空军雷达学院信息与指挥自动化系武汉430010 dept. of.ece University of Delaware Newark DE 19716 USA

为了提高距离分辨率而又不增加对发射/接收机带宽的要求,该文提出了频分多入多出(Frequency-Divided Multiple Input Multiple Output,FD-MIMO)雷达。该雷达利用同时发射的多路窄带信号合成宽带波形,进而得到目标的高分辨距离像。由于... 详细信息

为了提高距离分辨率而又不增加对发射/接收机带宽的要求,该文提出了频分多入多出(Frequency-Divided Multiple Input Multiple Output,FD-MIMO)雷达。该雷达利用同时发射的多路窄带信号合成宽带波形,进而得到目标的高分辨距离像。由于持续时间短,合成高分辨距离像具有很好的多普勒容限。此外,针对由合成频谱不连续性造成的近区高旁瓣和由子带间耦合造成的远区高旁瓣,该文分别提出使用倒数谱滤波器和对子带信号加带外衰减的方法予以抑制。最后,理论分析和数值仿真证明了旁瓣抑制方法的有效性。

关键词：频分多入多出雷达模糊函数高分辨距离像倒数谱滤波

Modeling of.tunneling current density of.GeC based double barrier multiple quantum well resonant tunneling diode

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Journal of.Semiconductors 2018年第10期39卷 34-38页

作者： Swagata Dey Vedatrayee Chakraborty Bratati Mukhopadhyay Gopa Sen Institute of.Radio Physics and Electronics University of CalcuttaKolkata 700009India B.p.Poddar Institute of.Management and Technology(ece dept. Kolkata 700052India

The double barrier quantum well（DBQW） resonant tunneling diode（RTD） structure made of.SiGeSn/GeC/SiGeSn alloys grown on Ge substrate is analyzed. The tensile strained Ge（1-z）Cz on Si（1-x-y）GexSny heterostructure provides a direct band gap type I configuration. The transmission coefficient and tunneling current density have been calculated considering single and multiple quantum wells. A comparative study of.tunnelling current of.the proposed structure is done with the existing RTD structure based on GeSn/SiGeSn DBH. A higher value of.the current density for the proposed structure has been obtained.

关键词： DBQW MQW RTD NDR tunneling current density