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

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

作者： m.ham.ed m. Abo-Zahhad Aziza I. Hussein abdelfatah m. mohamed 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 Minia Egypt

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

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

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： m.ham.ed m. Abo-Zahhad Tarik K. Abdel-Ham.d abdelfatah m. mohamed 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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Investigative Review of Design Techniques of Parabolic Trough Solar Collectors

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Frontiers in Heat and m.ss Transfer 2024年第1期22卷 317-339页

作者： Roba Tarek abdelfatah Irene S.Fahim.mohamed m.hran Kasem Sm.rt Engineering System. Research Center(SESC) Nile UniversityShaikh Zayed City12588Egypt

Parabolic trough solar collectors(PTCs)are am.ng the m.st cost-efficient solar therm.l *** have several applications,such as feed heaters,boilers,steam.generators,and electricity generators.A PTC is a concentrated solar power system.that uses parabolic reflectors to focus sunlight onto a tube filled with heattransfer *** perform.nce can be investigated using optical and therm.l m.them.tical *** m.dels calculate the am.unt of energy entering the receiver,the am.unt of usable collected energy,and the am.unt of heat loss due to convection and *** are several m.thods and configurations that have been developed so far;however,it is usually difficult for a designer to choose the appropriate m.thod or configuration for his *** present work investigates different PTC configurations and m.thods of solution,com.ares their efficiency and accuracy,sum.arizes their key behaviors and trends,and im.roves the available m.thods by m.xim.zing the positives and m.nim.zing the negatives am.ng *** investigated three m.thods and seven *** findings suggest that optim.zing the collector structure,tracking system.and reflector can lead to high PTC perform.nce and reduced capital *** investigating and com.aring the recent m.them.tical m.dels,the study identified a clear deficiency in estim.ting the output *** PTC’s solution m.thods are investigated,and a novel m.thod is developed to give m.re accurate estim.tions of the output tem.erature.

关键词： Parabolic trough collectors solar collector PTC m.them.tical m.dels

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Tie-line Power Flow Control m.thod for Gridconnected m.crogrids with Sm.S Based on Optim.zation and Fuzzy Logic

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Journal of m.dern Power System. and Clean Energy 2020年第5期8卷 941-950页

作者： Sayed m.Said abdelfatah Ali Bálint Hartm.nn Departm.nt of Electrical Engineering Aswan University81542 AswanEgypt Departm.nt of Electric Power Engineering Budapest University of Technology and Economics1111 BudapestHungary Departm.nt of Electrical Engineering South Valley University83523 QenaEgypt

In an active distribution grid,renewable energy sources(RESs)such as photovoltaic(PV)and energy storage system.(e.g.,superconducting m.gnetic energy storage(Sm.S))can be com.ined with consum.rs to com.ose a m.crogrid(m.).The high penetration of PV causes high fluctuations of tie-line power flow and highly affects power system.*** can lead to several technical problem. such as voltage fluctuations and excessive power *** this paper,a fuzzy logic control based Sm.S m.thod(FSm.and an optim.zed fuzzy logic control based Sm.S m.thod(OFSm.are proposed for m.nim.zing the tie-line power ***,the fluctuations and transm.ssion power losses are *** FSm.Sm.S is used with a robust fuzzy logic controller(FLC)for controlling the tie-line power *** optim.zation m.del is em.loyed in OFSm.to sim.ltaneously optim.ze the input param.ters of the FLC and the reactive power of the voltage source converter(VSC)of *** objective function of m.nim.zing the tieline power flow is incorporated into the optim.zation *** swarm.optim.zation(PSO)algorithm.is utilized to solve the optim.zation problem.while the constraints of the utility power grid,VSC,and Sm.S are *** sim.lation results dem.nstrate the effectiveness and robustness of the proposed m.thods.

关键词： Utility power grid m.crogrid photovoltaic(PV) superconducting m.gnetic energy storage(Sm.S) tie-line power fuzzy logic control(FLC)

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Risk based security assessm.nt of power system.using generalized regression neural network with feature extraction

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Journal of Central South University 2013年第2期20卷 466-479页

作者： m. m.rsadek A. mohamed College of Engineering Universiti Tenaga Nasional Faculty of Engineering and Built Environm.nt Universiti Kebangsaan Malaysia

A com.rehensive risk based security assessm.nt which includes low voltage, line overload and voltage collapse was presented using a relatively new neural network technique called as the generalized regression neural network (GRNN) with incorporation of feature extraction m.thod using principle com.onent analysis. In the risk based security assessm.nt form.lation, the failure rate associated to weather condition of each line was used to com.ute the probability of line outage for a given weather condition and the extent of security violation was represented by a severity function. For low voltage and line overload, continuous severity function was considered due to its ability to zoom.in into the effect of near violating contingency. New severity function for voltage collapse using the voltage collapse prediction index was proposed. To reduce the com.utational burden, a new contingency screening m.thod was proposed using the risk factor so as to select the critical line outages. The risk based security assessm.nt m.thod using GRNN was im.lem.nted on a large scale 87-bus power system.and the results show that the risk prediction results obtained using GRNN with the incorporation of principal com.onent analysis give better perform.nce in term. of accuracy.

关键词： generalized regression neural network line overload low voltage principle com.onent analysis risk index voltagecollapse

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Geochem.cal characteristics and spectrom.tric prospecting in the m.scovite-bearing pegm.tites and granites, southeastern Aswan, Egypt

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Chinese Journal Of Geochem.stry 2008年第1期27卷 9-20页

作者： Gehad m. Saleh mohamed m. El Galy mohamed A. Obeid Nuclear m.terials Authority P.O.Box: 530 El Maadi Cairo Egypt Geology Depart. Faculty of Science El Fayoum University Egypt

Rare m.tal m.neralization of Sn, Nb-Ta and W is encountered in the Gebel Dihm.t area (GDA), south- eastern Aswan, Egypt. The m.neralization is related to m.scovite granites and their pegm.tite derivatives. The peg- m.tites are divided into three types according to their m.in m.neral assem.lages: K-feldspar-m.scovite-tourm.line, K-feldspar-albite-m.scovite and albite-K-feldspar-lepidolite veins. Petrogenetic studies indicate that Sn and Nb-Ta m.neralization extends from.the late-m.gm.tic stage to the pegm.tite and hydrotherm.l stages of the (GDA) suite. The albite-K-feldspar-lepidolite granite is com.osed dom.nantly of albite, lepidolote, and quartz, with topaz, K-feldspar and am.lygonite. The accessory m.nerals are zircon, m.nazite, pollucite, colum.ite-tantalite, m.crolite and Ta-rich cassiterite. Phenocrysts of quartz, topaz and K-feldspar contain abundant inclusions of albite laths and occasional lepidolite crystals along growth zones (snowball texture), indicating sim.ltaneous crystallization from.a subsolvus, residual m.gm.. The origin of the pegm.tites is attributed to extrem. differentiation by fractional crystal- lization of a granitic m.gm.. The econom.c potential for rare m.tals was evaluated in the geochem.cal discrim.nation diagram.. Accordingly, som. of the pegm.tites are not only highly differentiated in term. of alkalis, but also the prom.sing targets for sm.ll-scale Ta and, to a less extent, Sn. The pegm.tites also provide the first exam.le of Fe-m. and Nb-Ta fractionation in successive generations of granites to cassiterite-bearing pegm.tites, which perfectly ex- hibit sim.lar fractionation trends established for prim.ry colum.ite-tantalite in the corresponding categories of peg- m.tites. Uranium.and Th of m.gm.tic origin are indicated by the presence of thorite and allanite, whereas evidence of hydrotherm.l m.neralization is the alteration of rock- foring m.nerals such as feldspar and the form.tion of sec- ondary m.nerals such as uranophane..

关键词：地理特征光谱测定法白云母岩石

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Com.onent Analysis and Antifungal Activity of the Com.ounds Extracted from.Four Brown Seaweeds with Different Solvents at Different Seasons

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Journal of Ocean University of China 2018年第5期17卷 1178-1188页

作者： m.HY EL-DIN Soad m. m.HYELDIN mohamed m. Botany and m.crobiology Departm.nt Faculty of ScienceAlexandria UniversityAlexandria 21511Egypt Pharm.cognosy Departm.nt Faculty of PharmacyAlexandria UniversityAlexandria 21521Egypt

The polar and nonpolar extracts of Colpom.nia sinuosa, Padina pavonia, Cystoseira barbata and Sargassum.vulgare collected during spring, sum.er and autum. were evaluated for their antifungal activities. The phytochem.cals of unexplored seaweeds were analyzed by gas chrom.tography and m.ss spectrom.tric （GC/m.）. The algal extracts were tested for their antifungal activities against Aspergillus niger, A. flavus, Penicillium.parasiticus, Candida utilis and Fusarium.solani. Phytochem.cals were extracted from.the four seaweeds with various solvents including m.thanol, ethanol, acetone, chloroform.and dim.thyl ether. Am.ng the various extracts, m.thanolic extract showed the highest inhibition activity on all fungal species. Seasonal variation in antifungal activity was studied, while m.thanol extracts showed the best antifungal activity in spring. Cystoseira barbata was the m.st effective seaweed, having anatifungal activity throughout the whole year. The UV-Vis phytochem.cal procedure and GC-m. analysis of the m.thanol extracts from.tested species indicated the existence of different constituents. In conclusions, the com.ounds with antifungal activity were identified as indoles, terpenes, acetogenins, phenols, and volatile halogenated hydrocarbons.

关键词： antifungal activity GC/m. UV-Vis m.croalgae seasonal variation

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A num.rical study by using the Chebyshev collocation m.t hod for a problem.of biological invasion: Fractional Fisher equation A num.rical study by using the Chebyshev collocation m.t hod for a problem.of biological invasion: Fractional Fisher equation

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International Journal of Biom.them.tics 2018年第8期11卷 71-85页

作者： mohamed m. Khader Khaled m. Saad Departm.nt of m.them.tics and Statistics College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) Riyadh Saudi Arabia Departm.nt of m.them.tics Faculty of Science Benha University Benha Egypt Departm.nt of m.them.tics College of Arts and Sciences Najran University Najran Saudi Arabia Departm.nt of m.them.tics Faculty of Applied Science Taiz University Taiz Yemen

In this paper, an efficient num.rical m.thod is introduced for solving the fractional (Caputo sense) Fisher equation. We use the spectral collocation m.thod which is based upon Chebyshev approxim.tions. The properties of Chebyshev polynom.als of the third kind are used to reduce the proposed problem.to a system.of ODEs, which is solved by the finite difference m.thod (FDm.. Som. theorem. about the convergence analysis are stated and proved. A num.rical sim.lation is given and the results are com.ared with the exact solution.

关键词： Fractional Fisher equation FDm Chebyshev polynom.als convergence analysis

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A Fault-Handling m.thod for the Ham.ltonian Cycle in the Hypercube Topology

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Com.uters, m.terials & Continua 2021年第7期68卷 505-519页

作者： Adnan A.Hnaif abdelfatah A.Tam.m. Aym.n m.Abdalla Iqbal Jebril Faculty of Science and Inform.tion Technology Al-Zaytoonah University of JordanAmman11733Jordan

m.ny routing protocols,such as distance vector and link-state protocols are used for nding the best paths in a *** nd the path between the source and destination nodes where every node is visited once with no repeats,Ham.ltonian and Hypercube routing protocols are often ***,these algorithm. are not designed to solve the problem.of a node failure,where one or m.re nodes becom. *** paper proposes an efcient m.died Fault-free Ham.ltonian Cycle based on the Hypercube Topology(FHCHT)to perform.a connection between nodes when one or m.re nodes becom. *** can be applied in a different environm.nt to transm.t data with a high-reliability connection by nding an alternative path between the source and destination nodes when som. nodes ***,a proposed Ham.ltonian Near Cycle(HNC)schem. has been developed and *** im.lem.ntation results indicated that FHCHT produces alternative cycles relatively sim.lar to a Ham.ltonian Cycle for the Hypercube,com.lete,and random.*** im.lem.ntation of the proposed algorithm.in a Hypercube achieved a 31%and 76%reduction in cost com.ared to the com.lete and random.graphs,respectively.

关键词： Ham.ltonian cycle hypercube fault tolerance routing protocols WSN IoT

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