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Applying and Comparison of Chaotic-Based Permutation Algorithms for Audio Encryption

Computers, materials & Continua 2021年第6期67卷 3161-3176页

作者： osama m.abu zaid medhat A.Tawfeek Saad Alanazi Department of Computer Science Faculty of Computers and InformationKafrelsheikh UniversityEgypt Department of Computer Science College of Computer and Information SciencesJouf UniversityKSA Department of Computer Science Faculty of Computers and InformationMenoua UniversityEgypt

This research presents,and claries the application of two permutation algorithms,based on chaotic map systems,and applied to a le of speech *** are the Arnold cat map-based permutation algorithm,and the Baker’s chaotic map-based permutation *** algorithms are implemented on the same speech signal ***,both the premier and the encrypted le histograms are documented and *** speech signal amplitude values with time signals of the original le are recorded and plotted against the encrypted and decrypted ***,the original le is plotted against the encrypted le,using the spectrogram frequencies of speech signals with the signal *** permutation algorithms are used to shufe the positions of the speech les signals’values without any changes,to produce an encrypted speech le.A comparative analysis is introduced by using some of sundry statistical and experimental analyses for the procedures of encryption and decryption,e.g.,the time of both procedures,the encrypted audio signals histogram,the correlation coefcient between specimens in the premier and encrypted signals,a test of the Spectral Distortion(SD),and the Log-Likelihood Ratio(LLR)*** outcomes of the different experimental and comparative studies demonstrate that the two permutation algorithms(Baker and Arnold)are sufcient for providing an efcient and reliable voice signal encryption ***,the Arnold’s algorithm gives better results in most cases as compared to the results of Baker’s algorithm.

关键词： Arnold’s cat map chaotic maps permutation algorithms speech encryption Baker’s chaotic map

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Regeneration mechanisms and therapeutic strategies for neuromuscular junctions in aging and diseases

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Neural Regeneration Research 2025年第1期20卷 193-194页

作者： masashi Fujitani abu md mamun Tarif Yoshinori Otani Department of Anatomy and Neuroscience Faculty of MedicineShimane UniversityShimaneJapan

The neuromuscular junction(NmJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NmJ structure is classically described as having a“pretzel-like”shape in mice(Figure 1),whereas human NmJs have a smaller,fragmented structure throughout *** NmJs exhibit smaller or fragmented endplates,partial denervation,reduced numbers of synaptic vesicles,abnormal presynaptic mitochondria,and dysfunctional perisynaptic Schwann cells(Alhindi et al.,2022).

关键词： aging structure Figure

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Genesis of nanocrystalline Ho_2O_3 via thermal decomposition of holmium acetate: Structure evolution and electrical conductivity properties

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Journal of Rare Earths 2019年第2期37卷 185-192页

作者： Bahaa m.abu-Zied Abdullah m.Asiri Center of Excellence for Advanced materials Research (CEAmR) King Abdulaziz University Chemistry Department Faculty of Science King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This study focuses on the preparation of nanostructured holmium oxide via the decomposition of holmium acetate precursor utilizing the non-isothermal strategy. Thermogravimetric analysis(TGA) was used to follow up the various thermal events involved in the decomposition process. Dehydration completes approximately at 150℃, which is followed by the decomposition of the anhydrous acetate leading to the formation of holmium oxide. Based on the TGA results the acetate precursor was heated non-isothermally at the temperature range of 150 e700℃. The obtained solids were characterized using powder X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), Fourier transform infrared spectroscopy(FT-IR), field-emission scanning electron microscopy(FE-SEm) and transmission electron microscopy(TEm). It is found that nanocrystalline Ho_2 O_3 starts to form at 500℃ and presents the only phase detected at the 500 e700℃ range. The electrical conductivity of the solids that form at the temperature range of 300 e700℃ was investigated. The obtained values were correlated with the observed structural modifications accompanying the heat treatment. The electrical conductivity of the Ho_2 O_3 samples prepared at 500, 600 and 700℃ reaches the values of 1.92 × 10^(-7), 1.61 × 10^(-7) and 8.33 × 10^(-8) Ω^(-1)cm^(-1) at a measuring temperature of 500℃, respectively. These values are potentially advantageous for high-resistivity devices.

关键词： Nanocrystalline Ho2O3 Thermal decomposition Ho2O3 Holmium oxide Rare earth oxides Nanomaterials

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Synthesis of Dy_2O_3 nanoparticles via hydroxide precipitation: effect of calcination temperature

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Journal of Rare Earths 2014年第3期32卷 259-264页

作者： Bahaa m.abu-Zied Abdullah m.Asiri Chemistry Department Faculty of Science King Abdulaziz University Center of Excellence for Advanced materials Research (CEAmR) King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This work described the preparation of dysprosium oxide, Dy203, nanoparticles using the homogeneous precipitation method. Dy3＋ ions were precipitated using NaOH solution. The obtained product was filtered, dried, and then calcined for 1 h at the temperature range of 300-700 ℃ in static air. The calcination temperature of the Dy-precttrsor was chosen based on its decomposi- tion as indicated by the TGA analysis. The crystalline structure and surface morphology of the calcined solids were studied by X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEm）, transmission electron microscopy （TEm） and X-ray pho- toelectron spectroscopy （XPS）. The obtained results revealed that Dy203 with crystallites size of 11-21 nm was formed at 500 ℃. Such value increased to 25-37 nm for the sample calcined at 700 ℃.

关键词： nanocrystalline dysprosium oxide Dy203 precipitation method Dy203 nanoparticles rare earths

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Fabrication,characterization,and electrical conductivity properties of Pr_6O_(11) nanoparticles

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Journal of Rare Earths 2013年第7期31卷 701-708页

作者： Bahaa m.abu-Zied Youssef A.mohamed Abdullah m.Asiri Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceAssiut University71516 AssiutEgypt Center of Excellence for Advanced materials Research(CEAmR) King Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

PrrOll nanoparticles were obtained by subsequent thermal decomposition of the as-prepared precipitate formed under ambient temperature and pressure using NaOH as precipitant. The calcination process was affected, for 1 h in static air atmosphere, at 400-700 ℃ temperature range. The different samples were characterized using X-ray diffraction （XRD）, transmission electron microscopy （TEm）, field emission scanning electron microscopy （FE-SEm）, thermogravimetric analysis （TGA）, in situ electrical conductivity, and N2 adsorption/desorption. The obtained results demonstrated that nano-crystalline Pr6O11, with crystallites size of 6-12 nm, started to form at 500 ℃. Such value increased to 20-33 nm for the sample calcined at 700℃. The as-synthesized PrrOll nanoparticles presented high electrical conductivity due to electron hopping between Pr（III）-Pr（IV） pairs.

关键词： nanocrystalline praseodymium oxide Pr6O11 nano structured materials electrical conductivity rare earths

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Correction of laser sweeping nonlinearities using ultralow-loss on-chip 7 m spiral resonators

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Photonics Research 2025年第1期13卷 40-48页

作者： osama TERRA WARREN JIN HUSSEIN KOTB JOEL GUO JOHN E.BOWERS Department of Electrical and Computer Engineering University of California Primary Length and Laser Technology Laboratory National Institute of Standards Anello Photonics Department of Electronics and Electrical Communication Engineering Faculty of EngineeringAin Shams University

Swept laser interferometry is an extremely powerful solution embedded in several recent technologies such as absolute distance measurement,light detection and ranging (LiDAR),optical frequency domain reflectometry,optical coherence tomography,microresonator characterization,and gas *** in the optical frequency sweeping of tunable lasers is a fatal drawback in gaining the expected outcome from these ***,we introduce an on-chip,millimeter-scale,7 m spiral resonator that is made of ultralow-loss Si3N4to act as a frequency ruler for correction of the tunable lasers sweeping *** sharp 2 mHz frequency lines of the 8.5×107high-quality factor resonator and the narrow-spaced 25.566 mHz frequency ticks of the 7 m spiral allow unprecedented precision for an on-chip solution to correct the laser sweeping *** measurements of the ruler’s frequency spacing,linewidth,and temperature and wavelength sensitivities of the frequency ticks are performed here to demonstrate the quality of the frequency *** addition,the spiral resonator is implemented in an frequency-modulated continuous-wave LiDAR experiment to demonstrate a potential application of the proposed on-chip frequency ruler.

关键词： Absolute distance measurement High power lasers Optical coherence tomography Optical frequency domain reflectometry Tunable diode lasers Tunable lasers

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AC-electronic and dielectric properties of semiconducting phthalocyanine compounds: a comparative study

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Journal of Semiconductors 2013年第11期34卷 1-6页

作者： Safa’a m.Hraibat Rushdi m-L.Kitaneh mohammad m.abu- Samreh Abdelkarim m.Saleh Al-Quds University Physics Dept.Abu DeesJerusalem P.O.Box 20002 Palestine via Israel

The AC-electronic and dielectric properties of different phthalocyanine films （ZnPc, CuPc, FePc, and H2Pc） were investigated over a wide range of temperature. Both real and imaginary parts of the dielectric constant （ε = ε1 - ε2） were found to be influenced by temperature and frequency. Qualitatively the behavior was the same for those compounds; however, the central atom, film thickness, and the electrode type play an important role in the variation of their values. The relaxation time, r, was strongly frequency-dependent at all temperatures and low frequencies, while a weak dependency is observed at higher frequencies. The relaxation activation energy was derived from the slopes of the fitted lines of In r and the reciprocal of the temperature （l/T）. The values of the activation energy were accounted for the hopping process at low temperatures, while a thermally activated conduction process was dominant at higher temperatures. The maximum barrier height, Wm, was found to be temperature and frequency dependent for all phthalocyanine compounds. The value Wm depends greatly on the nature of the central atom and electrode material type. The correlated barrier hopping model was found to be the appropriate mechanism to describe the charge carrier＇s transport in phthalocyanine films.

关键词： dielectric function organic semiconductor phthalocyanine relaxation time

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Deep Learning multimodal for Unstructured and Semi-Structured Textual Documents Classicatio

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Computers, materials & Continua 2021年第7期68卷 589-606页

作者： Nany Katamesh osama abu-Elnasr Samir Elmougy Faculty of Computers and Information Department of Computer ScienceMansoura University35516Egypt

Due to the availability of a huge number of electronic text documents from a variety of sources representing unstructured and semi-structured information,the document classication task becomes an interesting area for controlling data *** paper presents a document classication multimodal for categorizing textual semi-structured and unstructured *** multimodal implements several individual deep learning models such as Deep Neural Networks(DNN),Recurrent Convolutional Neural Networks(RCNN)and Bidirectional-LSTm(Bi-LSTm).The Stacked Ensemble based meta-model technique is used to combine the results of the individual classiers to produce better results,compared to those reached by any of the above mentioned models individually.A series of textual preprocessing steps are executed to normalize the input corpus followed by text vectorization *** techniques include using Term Frequency Inverse Term Frequency(TFIDF)or Continuous Bag of Word(CBOW)to convert text data into the corresponding suitable numeric form acceptable to be manipulated by deep learning ***,this proposed model is validated using a dataset collected from several spaces with a huge number of documents in every *** addition,the experimental results prove that the proposed model has achieved effective ***,upon investigating the PDF Documents classication,the proposed model has achieved accuracy up to 0.9045 and 0.959 for the TFIDF and CBOW features,***,concerning the JSON Documents classication,the proposed model has achieved accuracy up to 0.914 and 0.956 for the TFIDF and CBOW features,***,as for the XmL Documents classication,the proposed model has achieved accuracy values up to 0.92 and 0.959 for the TFIDF and CBOW features,respectively.

关键词： Document classication deep learning text vectorization convolutional neural network bi-directional neural network stacked ensemble

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A comparison between different ohmic contacts for ZnO thin films

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Journal of Semiconductors 2015年第3期36卷 41-45页

作者： Shadia J.Ikhmayies Naseem m.abu El-Haija Riyad N.Ahmad-Bitar AlIsra University Faculty of Information Technology Department of Basic Sciences-Physics Physics Department Faculty of Science University of Jordan

There are several metals that form ohmic contacts for ZnO thin films, such as copper, aluminum and silver. The aim of this work is to make a comparison between these ohmic contacts. To achieve this purpose, polycrystalline ZnO thin films were prepared by the spray pyrolysis technique, and characterized by the I-V measurements at room temperature. Two strips of each metal were thermally evaporated on the surface of the film and measurements were first recorded in the dark and room light, then in the dark before and after annealing for A1, which was found to be the best in the set. Films with aluminum contacts gave the smallest resistivity, best ohmicity and they are slightly affected by light as required. On the other hand, copper was found to be the worst, and films with copper contacts gave the largest resistivity, worst ohmicity and they are the most affected by light. Annealing improved the aluminum contacts due to alloying and doping.

关键词： transparent conducting oxide ohmic contacts annealing solar cells

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A Novel Design of Octal-Valued Logic Full Adder Using Light Color State model

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Computers, materials & Continua 2021年第6期67卷 3487-3503页

作者： Ahmed Talal osama abu-Elnasr Samir Elmougy Department of Computer Science Faculty of Computes and InformationMansoura UniversityMansoura35516Egypt

Due to the demand of high computational speed for processing big data that requires complex data manipulations in a timely manner,the need for extending classical logic to construct new multi-valued optical models becomes a challenging and promising research *** paper establishes a novel octal-valued logic design model with new optical gates construction based on the hypothesis of Light Color State model to provide an efficient solution to the limitations of computational processing inherent in the electronics *** provide new mathematical definitions for both of the binary OR function and the PLUS operation in multi valued logic that is used as the basis of novel construction for the optical full adder *** case studies were used to assure the validity of the proposed *** cases proved that the proposed optical 8-valued logic models provide significantly more information to be packed within a single bit and therefore the abilities of data representation and processing is increased.

关键词： mathematical modeling numerical simulations optical logic optics in computing multi-valued logic full adder

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