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Multi-Pattern Matching Algorithm with Wildcards Based on Bit-Parallelism

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Wuhan University Journal of.Natural Sciences 2017年第2期22卷 178-184页

作者： ahmed A. f. Saif.HU Liang CHU Jianf.ng College of.Computer Science and Technology Jilin University Changchun 130012 Jilin China

Multi-pattern matching with wildcards is a problem of.f.nding the occurrence of.all patterns in a pattern set {p^1,… ,p^k} in a given text t. If.the percentage of.wildcards in pattern set is not high, this problem can be solved using f.nite automata. We introduce a multi-pattern matching algorithm with a f.xed number of.wildcards to overcome the high percentage of.the occurrence of.wildcards in patterns. In our proposed method, patterns are matched as bit patterns using a sliding window approach. The window is a bit window that slides along the given text, matching against stored bit patterns. Matching process is executed using bit wise operations. The experimental results demonstrate that the percentage of.wildcard occurrence does not af.ect the proposed algorithm＇s perf.rmance and the proposed algorithm is more ef.icient than the algorithms based on the f.st f.urier transf.rm. The proposed algorithm is simple to implement and runs ef.iciently in O（n ＋ d（n/σ ）（m/w）） time, where n is text length, d is symbol distribution over k patterns, m is pattern length, and σ is alphabet size.

关键词： multi-pattern string matching wildcard bitparallelism

An energetic nano-f.ber composite based on polystyrene and 1,3,5-trinitro-1,3,5-triazinane f.bricated via electrospinning technique

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Def.nce Technology（防务技术） 2023年第9期27卷 1-8页

作者： Mahmoud Abdelhaf.z ahmed K.Hussein Waleed f.Khalil ahmed Elbeih Military TechnicalCollege(MTC) KobryElkobbahCairoEgypt Saf.ty f.elCycleDepartment NRSRCEgyptianAtomicEnergyAuthority(EAEA)CairoEgypt

Electrospinning is a simple technique used to f.bricate polymeric nano-f.brous *** nano-f.bers have f.und a wide range of.valuable applications in the biomedical ***,it has not been utilized with solid high explosives ***,the electrospinning technique has been used to f.bricate polystyrene(PS)/1,3,5-trinitro-1,3,5-triazinane(RDX)composite *** governed electrospinning parameters,voltage,distance f.om the collector,f.ow rate,mandrel rotating speed,time,and solution concentration,that greatly af.ect the morphology of.the obtained nanof.bers were *** f.bricated PS/RDX nano-f.bers were characterized using scanning electron microscopy(SEM),X-ray dif.ractometer(XRD),and f.urier Transf.rm Inf.ared(f.IR)*** impact and f.iction sensitivities of.PS/RDX were also *** thermal behavior of.the prepared composite and the pure materials were studied by the thermal gravimetric analysis technique(TGA).SEM results proved the f.brication of.PS/RDX f.bers in the nano-size via *** spectroscopy conf.rmed the existence of.the characteristic f.nctional groups of.both PS and RDX in the composite *** sharp peaks showed the conversion of.amorphous PS into crystalline shape via electrospinning and also conf.rmed the f.rmation of.PS/RDX *** PS f.bers absorbed the heat and increased the onset decomposition of.the pure RDX f.om 181.5 to 200.7℃in the case of.PS/RDX ***,PS/RDX nano-f.bers showed the relatively low impact and f.iction sensitivities of.100 J and 360 N *** results could introduce PS/RDX nanof.brous composite in the f.eld of.explosives detection with high levels of.saf.ty.

关键词： Electrospinning Nano-f.bers 1,3,5-Trinitro-1,3,5-triazinane(RDX) Polystyrene(PS) Sensitivity

Ef.ect of.f.nctionalized Multi-walled Carbon Nanotubes with Poly(N-vinyl pyrrolidone-co-2-acrylamido-2-methyl-1-propanesulf.nic acid) on the Release of.Tramadol Hydrochloride

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Chinese Journal of.Polymer Science 2015年第3期33卷 376-385页

作者： ahmed Awadallah-f.Tahia B.Mostaf. National Center f.r Radiation Research and Technology Chemistry Department University College for WomenAin Shams University

Multi-walled carbon nanotubes （MWCNTs） were graf.ed with poly（N-vinyl-2-pyrrolidone） and with poly（2- acrylamido-2-methyl-1-propanesulf.nic acid） at dif.erent compositions by using y-rays technique as initiator. The MWCNTs, MWCNT-graf.-PNVP, MWCNT-graf.-PAMPS and MWCNTs-graf.-P（NVP-co-AMPS） were characterized by f.urier transf.rm inf.a red （f.IR） spectroscopy, X-ray dif.raction （XRD）, thermal gravimetric analysis （TGA）, elemental analysis and high-resolution transmission electron microscopy （HR-TEM）. The results indicated that the graf.ing processes of.PNVP, PAMPS and P（NVP-co-AMPS） occurred on to the surf.ces of.MWCNTs without destroying the f.amework of.MWCNTs. Tramadol hydrochloride （TH） was loaded as model drug and its release behavior was analyzed via various kinetic models. Release of.the loaded TH was studied in simulated gastric f.uid （SGf. pH = 1.2） and simulated intestinal f.uid （SIf. pH = 7.4） at 37 ℃. Controlled release of.TH f.om graf.ed MWCNTs was investigated. The outcome results suggest that the graf.ed MWCNTs could be used as a promising matrix candidate f.r oral drug delivery system by harmonization between the composition and pH level of.the simulated biological f.uids.

关键词： Polymer graf.ing Gamma irradiation Multi-walled carbon nanotubes Controlled release Tramdol hydrochloride.

Sequence architecture of.a Jurassic ramp succession f.om Gebel Maghara(North Sinai,Egypt):Implications f.r eustasy

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Journal of.Palaeogeography 2015年第3期4卷 305-330页

作者： ahmed Awad Abdelhady f.anz Theodor f.rsich Geology Department Faculty of ScienceMinia University f. Pal?oumwelt Geozentrum Nordbayern der Universit?t Erlangen

The Jurassic succession at Gebet Maghara, North Sinai, Egypt, represents a mixed carbonate-siticictastic sequence. Combining inf.rmation f.om both f.ssits and rocks attowed a ptausibte reconstruction of.the depositionat environments and of.the basin evotution. The Ju- rassic succession of.Gebel Maghara was deposited on a ramp, and the architecture of.the ramp f.cies was strongty controtted not onty by sea-revel changes but atso by extensionat tectonics in connection with rif.ing of.the Tethys, North Gondwana. Seven tectonicalty modif.ed thirdorder sequences （DS 1-DS 7） have been recognized. The f.rst three sequences （DS 1-DS 3）, ranging f.om the Toarcian to the Bajocian, record sea invasion （intertidat to shattow subtida[lconditions） across an intracratonic area as a resutt of.eustatic sea-f.ver changes during a quiescent rif. stage. The remaining sequences （DS 4-DS 7） ref.ect open marine mid to outer ramp settings. Non-marine conditions around the Bajocian-Bathonian boundary, documented by catiche, represent the maximum regression of.the sea. During an active extensionat stage, horsts, which f.rmerty acted as barriers separating the Maghara sub-basin f.om the main ocean, subsided. Subsequent rejuvenation and reactivation of.f.utts shif.ed the homoctinat physiography of.the ramp to a distatty steepened ramp during the earty Bathonian, creating a 200-m-thick dettaic wedge. SimiLar processes during the earty Kimmeridgian created a catcirudite-catcarenite succession of.stope origin. The diversity and the epif.unat/inf.unat percentage of.the macrof.una disptay a cyctic pattern which coincides more or tess with the sequence stratigraphic architecture.

关键词： f.cies sequence stratigraphy ramp extensional basin Jurassic Gebel Maghara Egypt

Design, Sonosynthesis, Quantum-Chemical Calculations, and Evaluation of.New Mono-and Bis-pyridine Dicarbonitriles as Antiprolif.rative Agents

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Chinese Journal of.Chemistry 2020年第5期38卷 501-508页

作者： Wael Abdelgayd ahmed Araf. Modather f.Hussein Chemistry Department College of ScienceJouf UniversityP.O.Box 2014SakakaAljoufKingdom of Saudi Arabia Chemistry Department Faculty of ScienceFayoum UniversityP.O.Box 63514Fayoum CityEgypt Chemistry Department Faculty of ScienceAl-Azhar UniversityAsyut branchEgypt

A highly ef.icient,simple,and clean single-step sonosynthetic procedure has been sophisticated f.r assembling new series of.mono-and bis-pyridine dicarbonitriles f.om ketones,HCl,and *** presented protocol is applicable f.r the preparation of.a broad range of.uniquely substituted pyridine dicarbonitriles and seems to be superior in comparison with other previously reported *** antiprolif.rative impact of.the newly synthesized derivatives was screened towards three representative cancer cell lines(MCf.7,A549,and HCT116).Most of.the evaluated derivatives showed a moderate to excellent anti-prolif.rative activity towards the selected cell *** these,compounds 4h,4k,10,12a,and 12b showed both potent anticancer activity(ICs0f.ect(ICs0>58μM)on non-tumorigenic cells(MCf.10A and NCM460),suggesting their promising potential to be lead molecules f.r f.ture antitumor drug *** structure-activity relationships have been also ***,quantum chemical studies based on Density f.nctional Theory(Df.)of.the synthesized compounds were investigated and f.und to be consistent with the in vitro inhibitory activities.

关键词： pyridine nitrile synthesis

Hyperspectral imaging and remote trace detection of.cis-1,3,4,6-tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHMX)compared with traditional explosives using laser induced f.uorescence

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Def.nce Technology（防务技术） 2021年第5期17卷 1609-1616页

作者： Hany S.Ayoub Ashraf.f.El-Sherif.ahmed Elbeih Department of.Physics Faculty of ScienceCairo UniversityEgypt Laser Photonics Research Center Engineering Physics DepartmentMilitary Technical CollegeCairoEgypt Explosives Department Military Technical CollegeKobry ElkobbahCairoEgypt

cis-1,3,4,6-Tetranitrooctahydroimidazo-[4,5 d]imidazole(BCHMX)is an advanced energetic compound that expected to spread worldwide in the near ***,no approved remote detection methods were reported in current literature f.r this material,we perf.rmed hyper-spectral imaging and laser induced f.uorescence(LIf.to a BCHMX sample under low laser f.uence f.r determining the optimum laser wavelength used in any f.ture BCHMX-LIf.based remote detection *** this purpose,an experimental setup consisted of.a sun spectrum lamp and hyper-spectral camera was built to illuminate and image white powder samples of.BCHMX in comparison with the traditional explosives,HMX(1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane),RDX(1,3,5-trinitro-1,3,5-triazacyclohexane),PETN(2,2-Bis[(nitroxy)methyl]propane-1,3-diyldinitrate).The imaging reveals strong BCHMX sample absorption contrast among other samples at wavelength ranging f.om 400 to 410 *** light source was replaced by a 405 nm laser diode illuminator,a strong BCHMX sample LIf.at the spectral range f.om 425 to 700 nm was observed under low laser f.uence condition of.0.1 mJ/cm^(2).f.nally,we demonstrated successf.lly the ability of.the 405 nm LIf.and the hyperspectral imaging technique to detect f.nger print traces of.BCHMX on white cellulose f.bric f.om a distance of.15 m and a detection limit of.1 mg/cm^(2).

关键词： Hyperspectral imaging Remote trace detection BCHMX Laser induced f.uorescence

Automatic Correction of.DEM Surf.ce Errors

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Journal of.Geographic Inf.rmation System 2017年第3期9卷 326-338页

作者： ahmed f. Elaksher Civil Engineering Department Cal Poly University Pomona CA USA

The automation of.extracting planner surf.ces is a main f.eld of.research in digital photogrammetry. These surf.ces are essential to generate three dimensional GIS databases. Surf.ces are usually determined f.om either DEMs or images. Each dataset provides a dif.erent type of.inf.rmation. Thus, the combination of.the two datasets should enhance the surf.ce reconstruction process. This paper presents a new technique f.r generating 3D surf.ces by combining both correlation-based DEMs and aerial images. The process starts by discriminating DEM points that represent planner surf.ces using local statistics of.neighboring elevations and intensities and point elevations. A segmented orthophoto is then used to group these points into dif.erent regions. The elevations of.the points in each region are f.d into a least squares adjustment model to compute the best-f.t planner surf.ce parameters. Ref.nement of.surf.ce borders is then perf.rmed using a region growing algorithm. The RMSE f.r f.ve test sites showed a spatial accuracy of.5 - 8 cm.

关键词： Photogrammetry DEM Orthophoto Planner Surf.ces

Elaboration of.ZnO nanowires by solution based method,characterization and solar cell applications

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Journal of.Semiconductors 2018年第9期39卷 8-14页

作者： f.A.Mahmoud Ninet ahmed Solid State Physics Department Physics Division National Research Centre Solar Cell Laboratory Center of Excellence for Advanced Sciences National Research Center Photovoltaic Department Electronics Research Institute

ZnO nanowires（NWs）layers have been synthesized using a two-step chemical solution method on ITO glass substrates coated with ZnO seeds at dif.erent immersing *** structures,morphology and optical properties of.the synthesized ZnO NWs have been *** prepared ZnO NWs have an obvious polycrystalline hexangular wurtzite structure and are pref.rentially oriented along the c-axis（002）.f.SEM micrographs showed that the prepared ZnO NWs are close to being vertically grown and more densely at higher immersing ***[2-methoxy-5（2-′-ethyl-hexyloxy）-1,4-phenylenevinylene],MEH-PPV,was used as an active layer to prepare three samples of.MEH-PPV/ZnO solar cell based on ZnO NWs that were prepared at dif.erent immersing times.A maximum power conversion ef.iciency of.0.812%was achieved f.r MEH-PPV/ZnO solar cell prepared at a higher immersing *** improved ef.iciency may be attributed to the enhancement of.both open-circuit voltage and f.ll f.ctor.

关键词： ZnO nanowires two step chemical solution method structural properties optical properties MEH-PPV/ZnO solar cell

Ef.ect of.Surf.ctant Concentration on Aqueous LiBr Solution Absorption Rate

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Open Journal of.Physical Chemistry 2013年第1期3卷 1-6页

作者： ahmed f. Elsaf.y College of.Engineering and Technology AUM—American University of the Middle East Egaila Kuwait

It is well known that small amounts of.surf.ctants, such as 1-Octanol, in the aqueous solution can increase the absorption rate signif.cantly. In this paper, experimental data were obtained f.r absorption of.water vapour into an aqueous LiBr solution with dif.erent concentrations of.1-Octanol. An experimental rig was specif.cally designed and developed in this work in order to investigate the ef.ect of.surf.ctant (1-Octanol) on the enhancement of.the heat and mass transf.r in the absorption process, in addition to, the investigation of.the impact of.the use of.magnetic stirrer inside the absorber. The experimental rig f.r this study was based on the ref.igeration mode of.the intermittent vapour absorption system. In order to study the heat and mass transf.r in water-lithium bromide vapour absorption air conditioning systems, it was necessary to monitor the concentration of.the solution continuously. As a consequence, two procedures f.r obtaining the LiBr solution concentration were used. The f.rst method was based on the measurement of.the density and temperature of.the solution, while the second was based on its electrolyte conductivity and the temperature. The experimental results showed that the surf.ctant concentration has a signif.cant ef.ect on the absorption rate;this is called the Marangoni instability. It has been concluded that, in order to clarif. the absorption enhancement phenomenon, it is necessary to understand the physicochemical aspects of.the absorption process and the ef.ect of.surf.ctants on the enhancement of.such process. Additionally, it has been concluded that new approaches are needed to explain the observed behaviour.

关键词： Absorption Surf.ctant Electrolyte Conductivity Binary Solutions