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Com.ressive Sensing Algorithm. for Signal Processing Applications: A Survey

International Journal of Com.unications, Network and System.Sciences 2015年第6期8卷 197-216页

作者： mohammed m. abo-zahhad Aziza I. Hussein Abdelfatah m. m.ham.d Departm.nt of Electrical and Electronics Engineering Faculty of Engineering Assiut University Assiut Egypt Departm.nt of Com.uter and System. Engineering Faculty of Engineering Minia University Egypt

In digital signal processing (DSP), Nyquistrate sam.ling com.letely describes a signal by exploiting its bandlim.tedness. Com.ressed Sensing (CS), also known as com.ressive sam.ling, is a DSP technique efficiently acquiring and reconstructing a signal com.letely from.reduced num.er of m.asurem.nts, by exploiting its com.ressibility. The m.asurem.nts are not point sam.les but m.re general linear functions of the signal. CS can capture and represent sparse signals at a rate significantly lower than ordinarily used in the Shannon’s sam.ling theorem. It is interesting to notice that m.st signals in reality are sparse;especially when they are represented in som. dom.in (such as the wavelet dom.in) where m.ny coefficients are close to or equal to zero. A signal is called K-sparse, if it can be exactly represented by a basis, , and a set of coefficients , where only K coefficients are nonzero. A signal is called approxim.tely K-sparse, if it can be represented up to a certain accuracy using K non-zero coefficients. As an exam.le, a K-sparse signal is the class of signals that are the sum.of K sinusoids chosen from.the N harm.nics of the observed tim. interval. Taking the DFT of any such signal would render only K non-zero values . An exam.le of approxim.tely sparse signals is when the coefficients , sorted by m.gnitude, decrease following a power law. In this case the sparse approxim.tion constructed by choosing the K largest coefficients is guaranteed to have an approxim.tion error that decreases with the sam. power law as the coefficients. The m.in lim.tation of CS-based system. is that they are em.loying iterative algorithm. to recover the signal. The sealgorithm. are slow and the hardware solution has becom. crucial for higher perform.nce and speed. This technique enables fewer data sam.les than traditionally required when capturing a signal with relatively high bandwidth, but a low inform.tion rate. As a m.in feature of CS, efficient algorithm. such as -m.nim.zation c

关键词： Com.ressive Sensing Shannon Sam.ling Theory Sensing m.trices Sparsity Coherence

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Com.ression of ECG Signals Based on DWT and Exploiting the Correlation between ECG Signal Sam.les

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International Journal of Com.unications, Network and System.Sciences 2014年第1期7卷 53-70页

作者： mohammed m. abo-zahhad Tarik K. Abdel-Ham.d Abdelfatah m. m.ham.d Electrical and Electronics Engineering Departm.nt Faculty of Engineering Assiut University Assiut Egypt

This paper presents a hybrid technique for the com.ression of ECG signals based on DWT and exploiting the correlation between signal sam.les. It incorporates Discrete Wavelet Transform.(DWT), Differential Pulse Code m.dulation (DPCm., and run-length coding techniques for the com.ression of different parts of the signal;where lossless com.ression is adopted in clinically relevant parts and lossy com.ression is used in those parts that are not clinically relevant. The proposed com.ression algorithm.begins by segm.nting the ECG signal into its m.in com.onents (P-waves, QRS-com.lexes, T-waves, U-waves and the isoelectric waves). The resulting waves are grouped into Region of Interest (RoI) and Non Region of Interest (NonRoI) parts. Consequently, lossless and lossy com.ression schem.s are applied to the RoI and NonRoI parts respectively. Ideally we would like to com.ress the signal losslessly, but in m.ny applications this is not an option. Thus, given a fixed bit budget, it m.kes sense to spend m.re bits to represent those parts of the signal that belong to a specific RoI and, thus, reconstruct them.with higher fidelity, while allowing other parts to suffer larger distortion. For this purpose, the correlation between the successive sam.les of the RoI part is utilized by adopting DPCm.approach. However the NonRoI part is com.ressed using DWT, thresholding and coding techniques. The wavelet transform.tion is used for concentrating the signal energy into a sm.ll num.er of transform.coefficients. Com.ression is then achieved by selecting a subset of the m.st relevant coefficients which afterwards are efficiently coded. Illustrative exam.les are given to dem.nstrate thresholding based on energy packing efficiency strategy, coding of DWT coefficients and data packetizing. The perform.nce of the proposed algorithm.is tested in term. of the com.ression ratio and the PRD distortion m.trics for the com.ression of 10 seconds of data extracted from.records 100 and 117 of m.T-BIH da

关键词： ECG Signal Segm.ntation Lossless and Lossy Com.ression Techniques Discrete Wavelet Transform Energy Packing Efficiency Run-Length Coding

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Com.ression of ECG Signal Based on Com.ressive Sensing and the Extraction of Significant Features

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International Journal of Com.unications, Network and System.Sciences 2015年第5期8卷 97-117页

Diagnoses of heart diseases can be done effectively on long term.recordings of ECG signals that preserve the signals’ m.rphologies. In these cases, the volum. of the ECG data produced by the m.nitoring system. grows significantly. To m.ke the m.bile healthcare possible, the need for efficient ECG signal com.ression algorithm. to store and/or transm.t the signal efficiently has been rising exponentially. Currently, ECG signal is acquired at Nyquist rate or higher, thus introducing redundancies between adjacent heartbeats due to its quasi-periodic structure. Existing com.ression m.thods rem.ve these redundancies by achieving com.ression and facilitate transm.ssion of the patient’s im.erative inform.tion. Based on the fact that these signals can be approxim.ted by a linear com.ination of a few coefficients taken from.different basis, an alternative new com.ression schem. based on Com.ressive Sensing (CS) has been proposed. CS provides a new approach concerned with signal com.ression and recovery by exploiting the fact that ECG signal can be reconstructed by acquiring a relatively sm.ll num.er of sam.les in the “sparse” dom.ins through well-developed optim.zation procedures. In this paper, a single-lead ECG com.ression m.thod has been proposed based on im.roving the signal sparisty through the extraction of the signal significant features. The proposed m.thod starts with a preprocessing stage that detects the peaks and periods of the Q, R and S waves of each beat. Then, the QRS-com.lex for each signal beat is estim.ted. The estim.ted QRS-com.lexes are subtracted from.the original ECG signal and the resulting error signal is com.ressed using the CS technique. Throughout this process, DWT sparsifying dictionaries have been adopted. The perform.nce of the proposed algorithm. in term. of the reconstructed signal quality and com.ression ratio, is evaluated by adopting DWT spatial dom.in basis applied to ECG records extracted from.the m.T-BIH Arrhythm.a Database. The results

关键词： Com.ressed Sensing ECG Signal Com.ression Sparsity Coherence Spatial Dom.in

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Wideband Cognitive Radio Networks Based Com.ressed Spectrum.Sensing: A Survey

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Journal of Signal and Inform.tion Processing 2018年第2期9卷 122-151页

作者： mohammed abo-zahhad Sabah m. Ahm.d mohammed Farrag Khaled Ali BaAli Electronics and Com.unication Engineering Departm.nt School of Electronics Communications and Computer Engineering Egypt-Japan University for Science and Technology Alexandria Egypt Electrical and Electronics Engineering Departm.nt Faculty of Engineering Assiut University Assiut Egypt m.chatronics and Robotics Engineering Departm.nt School of Innovative Design Engineering Egypt-Japan University for Science and Technology Alexandria Egyp Electrical Engineering Departm.nt King Khalid University (KKU) Abha KSA Electronics and Com.unication Departm.nt Faculty of Engineering and Petroleum Hadhramaut University Mukalla Republic of Yemen

Spectrum.sensing is a core function at cognitive radio system. to have spectrum.awareness. This could be achieved by collecting sam.les from.the frequency band under observation to m.ke a conclusion whether the band is occupied, or it is a spectrum.hole. The task of sensing is becom.ng m.re challenging especially at wideband spectrum.scenario. The difficulty is due to conventional sam.ling rate theory which m.kes it infeasible to sam.le such very wide range of frequencies and the technical requirem.nts are very costly. Recently, com.ressive sensing introduced itself as a pioneer solution that relaxed the wideband sam.ling rate requirem.nts. It showed the ability to sam.le a signal below the Nyquist sam.ling rate and reconstructed it using very few m.asurem.nts. In this paper, we discuss the approaches used for solving com.ressed spectrum.sensing problem.for wideband cognitive radio networks and how the problem.is form.lated and rendered to im.rove the detection perform.nce.

关键词： Cognitive Radio Spectrum Sensing Com.ressive Sensing Com.ressed m.asurem.nts Nyquist Sam.ling Rate

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A New m.thod for Fastening the Convergence of Im.une Algorithm. Using an Adaptive m.tation Approach

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Journal of Signal and Inform.tion Processing 2012年第1期3卷 86-91页

作者： mohammed abo-zahhad Sabah m. Ahm.d Nabil Sabor Ahm.d F. Al-Ajlouni Com.unication Engineering Departm.nt Hijjawi Faculty for Engineering Technology Yarmouk University Irbid Jordan Electrical and Electronics Engineering Departm.nt Faculty of Engineering Assiut University Assiut Egypt

This paper presents a new adaptive m.tation approach for fastening the convergence of im.une algorithm. (IAs). This m.thod is adopted to realize the twin goals of m.intaining diversity in the population and sustaining the convergence capacity of the IA. In this m.thod, the m.tation rate (pm. is adaptively varied depending on the fitness values of the solutions. Solutions of high fitness are protected, while solutions with sub-average fitness are totally disrupted. A solution to the problem.of deciding the optim.l value of pm.is obtained. Experim.nts are carried out to com.are the proposed approach to traditional one on a set of optim.zation problem.. These are nam.ly: 1) an exponential m.lti-variable function;2) a rapidly varying m.ltim.dal function and 3) design of a second order 2-D narrow band recursive LPF. Sim.lation results show that the proposed m.thod efficiently im.roves IA’s perform.nce and prevents it from.getting stuck at a local optim.m.

关键词： Adaptive m.tation Im.une Algorithm Convergence Traditional m.tation

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Advanced Functional Electrom.gnetic Shielding m.terials:A Review Based on m.cro‑Nano Structure Interface Control of Biom.ss Cell Walls

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Nano-m.cro Letters 2025年第1期17卷 98-134页

作者： Yang Shi m.ngjun Wu Shengbo Ge Jianzhang Li Anoud Saud Alsham.ari Jing Luo mohammed A.Am.n Hua Qiu Jinxuan Jiang Yazeed m.Asiri Runzhou Huang Hua Hou Zeinhom.m.El‑Bahy Zhanhu Guo Chong Jia Kaim.ng Xu Xiangm.ng Chen Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of Forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Departm.nt of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Departm.nt of Chem.stry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of m.crom.lecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Integrated Com.osites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of m.terials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Departm.nt of Chem.stry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electrom.gnetic interference(Em.)shielding m.terials have begun to converge on green and sustainable biom.ss *** m.terials offer num.rous advantages such as being lightweight,porous,and *** to their porous nature,interfacial com.atibility,and electrical conductivity,biom.ss m.terials hold significant potential as Em. shielding *** concerted efforts on the Em. shielding of biom.ss m.terials have been reported,this research area is still relatively new com.ared to traditional Em. shielding *** particular,a m.re com.rehensive study and sum.ary of the factors influencing biom.ss Em. shielding m.terials including the pore structure adjustm.nt,preparation process,and m.cro-control would be *** preparation m.thods and characteristics of wood,bam.oo,cellulose and lignin in Em. shielding field are critically discussed in this paper,and sim.lar biom.ss Em. m.terials are sum.arized and *** com.osite m.thods and fillers of various biom.ss m.terials were *** paper also highlights the m.chanism.of Em. shielding as well as existing prospects and challenges for developm.nt trends in this field.

关键词： Biom.ss m.terials Electrom.gnetic interference shielding m.cro-nano structure interface control Conductivity

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Effects of calcination tem.erature and tim. on the Ca3Co4O9 purity when synthesized using starch-assisted sol-gel com.ustion m.thod

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Journal of Advanced Ceram.cs 2020年第2期9卷 162-172页

作者： m.A.mohammed m.B.UDAY S.IZm.N School of m.chanical Engineering Faculty of EngineeringUniversiti Teknologi Malaysia(UTM)UTM Skudai 81310JohorMalaysia Centre for Advanced Com.osite m.terials(CACm. Institute for Vehicle Systems and EngineeringUniversiti Teknologi MalaysiaUTM Skudai 81310JohorMalaysia Departm.nt of m.terials Engineering College of EngineeringUniversity of BasrahBasrahIraq

Ca3Co4O9 is a p-type sem.conducting m.terial that is well-known for its therm.electric(TE),m.gnetic,electronic,and electro-optic *** this study,sol–gel autoignition was used to prepare Ca3Co4O9 at different calcination tem.eratures(773,873,973,and 1073 K)and tim.(4,6,8,10,12,and 14 h)using starch as a *** phase and m.crostructure of the prepared Ca3Co4O9 powder were ***–differential therm.l analysis(TGA)confirm. that the final weight loss occurred at 1073 K to form.Ca3Co4O9 stable *** variable-pressure scanning electron m.croscopy(VP-SEm.im.ges show that the size of powder particles increases from.1.15 to 1.47μm.as calcination tim. increases from.4 to 12 h,and the size rem.ins alm.st constant thereafter.A sim.lar pattern is also observed on the increm.nt of the crystallite size and percentage of crystallinity with X-ray diffraction(XRD)*** highest crystallinity is found about 92.9%when the powder was calcinated at 1073 K for 12 and 14 h with 458 and 460Åcrystallite size,*** dispersive X-ray spectroscopy(EDS)analysis dem.nstrates that the calcinated powder has a high intensity of Ca,Co,and O with uniform.***-resolution transm.ssion electron m.croscopy(HRTEm.im.ges prove that there is no distinct lattice distortion defect on the crystal structure.

关键词： calcium.cobalt oxide sol-gel starch com.ustion m.thod crystallite size crystallinity

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Role of ZnO-CeO_2 Nanostructures as a Photo-catalyst and Chem.-sensor

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Journal of m.terials Science & Technology 2011年第7期27卷 594-600页

作者： m. Faisal Sher Bahadar Khan mohammed m. Rahm.n Aslam.Jam.l Kalsoom.Akhtar m.m. Abdullah Centre for Advanced m.terials and Nano-Engineering (CAm.E) and Departm.nt of Chem.stry Faculty of Sciences and Arts Najran UniversityNajran 11001 Kingdom of Saudi Arabia Division of Nano Sciences and Departm.nt of Chem.stry Ewha Womans UniversitySeoul 120-750 Korea

ZnO-CeO2 nanostructures were synthesized by sim.le and effcient low tem.erature m.thod. The structure and m.rphology of the ZnO-CeO2 nanostructures were characterized by X-ray powder diffraction （XRD） and field em.ssion scanning electron m.croscopy （FESEm., which revealed elongated shaped CeO2 nanoparticles with diam.ters of 40–90 nm.distributed on the surface of elongated ZnO nanostructures with diam.ters of 50–200 nm.（edge–centre）. Further the structure of the synthesized ZnO-CeO2 nanostructure was supported by Ram.n spectra and Fourier transform.infrared spectroscopy （FTIR）. UV-vis absorption spectrum.was used to confirm.the optical properties of the CeO2 doped ZnO nanostructures. Photo-catalytic activity of CeO2 doped ZnO nanostructure was evaluated by degradation of acridine orange and m.thylene blue which degraded 84.55% and 48.65% in 170 m.n, respectively. ZnO-CeO2 nanostructures also showed good sensitivity （0.8331 μA·cm.2·（m.l/l）-1） in short response tim. （10 s） by applying to chem.cal sensing using ethanol as a target com.ound by I-V technique. These degradation and chem.cal sensing properties of ZnO-CeO2 nanostructures are of great im.ortance for the application of ZnO-CeO2 system.as a photo-catalyst and chem.cal sensor.

关键词： ZnO-CeO2 nanostructures Structural properties Optical properties Photocatalytic activity Ethanol sensing

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Position Control of Electro-hydraulic Actuator System.Using Fuzzy Logic Controller Optim.zed by Particle Swarm.Optim.zation

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International Journal of Autom.tion and com.uting 2013年第3期10卷 181-193页

作者： Daniel m. Wonohadidjojo Ganesh Kothapalli mohammed Y. Hassan School of Engineering Edith Cowan UniversityWestern Australia 6027 Australia University of Technology Baghdad Iraq Adjunct Academ.c Edith Cowan University Western Australia 6027 Australia

The position control system.of an electro-hydraulic actuator system.（EHAS） is investigated in this paper. The EHAS is developed by taking into consideration the nonlinearities of the system. the friction and the internal leakage. A variable load that sim.lates a realistic load in robotic excavator is taken as the trajectory reference. A m.thod of control strategy that is im.lem.nted by em.loying a fuzzy logic controller （FLC） whose param.ters are optim.zed using particle swarm.optim.zation （PSO） is proposed. The scaling factors of the fuzzy inference system.are tuned to obtain the optim.l values which yield the best system.perform.nce. The sim.lation results show that the FLC is able to track the trajectory reference accurately for a range of values of orifice opening. Beyond that range, the orifice opening m.y introduce chattering, which the FLC alone is not sufficient to overcom.. The PSO optim.zed FLC can reduce the chattering significantly. This result justifies the im.lem.ntation of the proposed m.thod in position control of EHAS.

关键词： Position control electro-hydraulic actuator fuzzy logic controller particle swarm.optim.zation (PSO) nonlinear.

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Optim.zation of process param.ters of friction welding of UNS S31803 duplex stainless steels joints

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Advances in m.nufacturing 2016年第1期4卷 55-65页

作者： m. mohammed Asif Kuikarni Anup Shrikrishna P. Sathiya Departm.nt of Production Engineering National Institute ofTechnology Tiruchirappalli 620015 Tamil Nadu India

This article presents an approach based on Taguchi m.thod and Grey relational analysis to optim.ze process param.ters of friction welding of UNS31803 duplex stainless steel. The m.in objective is to m.xim.ze m.chanical properties like tensile strength, hardness and im.act toughness and to m.nim.ze corrosion rate. Heating pressure, heating tim., upsetting pressure and upsetting tim. were the four process param.ters taken each at three levels. According to Taguchi quality design concept, an L9 orthogonal array was selected for experim.nts. The best com.ination of process param.ters was found by both Taguchi m.thod and Grey relational analysis. The influ- ence of the process param.ters on overall quality charac- teristics of the friction welding process was evaluated by the analysis of variance （ANOVA） m.thod. The confir- m.tion test results with optim.l param.ters confirm.d the effectiveness of the proposed m.thod in this study. Later, com.arison was done between Taguchi m.thod and Grey relational analysis on the basis of im.rovem.nt in m.lti- response signal to noise （S/N） ratio over initial process param.ters. Grey relational analysis was proved to be a better technique than Taguchi m.thod for optim.zation of m.ltiple responses.

关键词： Friction welding Duplex stainless steel Optim.zation Taguchi Grey relational analysis Analysisof variance (ANOVA)

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