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Structural Analysis for Qazzaz Metamorphic Core Complex,Northwestern Arabian Shield,Saudi Arabia

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Acta Geologica Sinica(English Edition) 2024年第5期98卷 1187-1201页

作者： Mansour H.AL-HASHIM osama M.K.KASSEM Department of Geology and Geophysics College of ScienceKing Saud University11451 RiyadhSaudi Arabia Department of Geology National Research CenterCairoEgypt

Identifying deformational mechanisms and associated structures at various scales,ranging from regional-scale structures to microscopic fabric,is crucial for the assessment of tectonic ***-three samples were taken from the Qazzaz metamorphic core complex to estimate the finite strain for felsic and mafic *** samples included gneisses rocks,monzogranite,and metavolcano-sedimentary rocks for both the Thalbah and Bayda *** the Rf/j and Fry methods,the axial ratios(XZ)range about 2.20 to 7.10 and 1.90 to 9.10,*** various rock units,the strain measurements show moderate to highly *** of the observed samples show shallow WNW dipping along a N to WNW trend of finite strain(X).The short axes(Z)based to be subvertical foliation related with a subhorizontal *** results demonstrate that contacts generated at semi-brittle to ductile deformation and that the strain of magnitude has the same value for different lithologic *** concluded that nappe generation in orogens results from pure shear deformation.

关键词： Finite strain metamorphic core complex Qazzaz area Saudi Arabia

Gear Drive Mechanism for Continuous Variable Valve Timing of IC Engines

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Engineering（科研） 2013年第3期5卷 245-250页

作者： osama H. M. Ghazal mohamad S. H. Dado Mechanical Engineering Department Applied Science Private University Amman Jordan

Continuous variable valve actuating (CVVA) technology provides high potential in achieving high performance, low fuel consumption and pollutant reduction. To get full benefits from (CVVT) various types of mechanisms have been proposed and designed. Some of these mechanisms are in production and have shown significant benefits in improving engine performance. In this investigation a newly designed gear drive mechanism that controls the intake valve opening (IVO) and closing (IVC) angles is studied. The control scheme is based on maximizing the engine brake power (P) and specific fuel consumption (BSFC) at any engine speed by continuously varying the phase between the cam shaft angle and the crank shaft angle. A single-cylinder engine is simulated by the “LOTUS” software to find out the optimum phase angle for maximum power and minimum fuel consumption at a given engine speed. The mechanism is a planetary gear drive designed for precise and continuous control. This mechanism has a simple design and operation conditions which can change the phase angle without limitation.

关键词： Mechanism Design Planetary Gear Variable Valve Timing Spark Ignition Engines Performance

Digital Continuity Guarantee Approach of Electronic Record Based on Data Quality Theory

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Computers, Materials & Continua 2020年第6期63卷 1471-1483页

作者： Yongjun Ren Jian Qi Yaping Cheng Jin Wang osama Alfarraj School of Computer and Software Engineering Research Center of Digital ForensicsMinistry of EducationNanjing University of Information Science&TechnologyNanjing210044China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing210044China School of Computer&Communication Engineering Changsha University of Science&TechnologyChangsha410114China Computer Science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia

Since the British National Archive put forward the concept of the digital continuity in 2007,several developed countries have worked out their digital continuity action ***,the technologies of the digital continuity guarantee are still *** first,this paper analyzes the requirements of digital continuity guarantee for electronic record based on data quality theory,then points out the necessity of data quality guarantee for electronic ***,we convert the digital continuity guarantee of electronic record to ensure the consistency,completeness and timeliness of electronic record,and construct the first technology framework of the digital continuity guarantee for electronic ***,the temporal functional dependencies technology is utilized to build the first integration method to insure the consistency,completeness and timeliness of electronic record.

关键词： Electronic record digital continuity data quality

A secure image steganography algorithm based on least significant bit and integer wavelet transform

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Journal of Systems Engineering and Electronics 2018年第3期29卷 639-649页

作者： ELSHAZLY Emad ABDELWAHAB Safey ABOUZAID Refaat ZAHRAN osama ELARABY Sayed ELKORDY Mohamed Engineering Department Nuclear Research CenterAtomic Energy AuthorityCairo 11787Egypt Electronics and Electrical Communications Engineering Department Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt

The rapid development of data communication in modern era demands secure exchange of information. Steganography is an established method for hiding secret data from an unauthorized access into a cover object in such a way that it is invisible to human eyes. The cover object can be image, text, audio,or video. This paper proposes a secure steganography algorithm that hides a bitstream of the secret text into the least significant bits（LSBs） of the approximation coefficients of the integer wavelet transform（IWT） of grayscale images as well as each component of color images to form stego-images. The embedding and extracting phases of the proposed steganography algorithms are performed using the MATLAB software. Invisibility, payload capacity, and security in terms of peak signal to noise ratio（PSNR） and robustness are the key challenges to steganography. The statistical distortion between the cover images and the stego-images is measured by using the mean square error（MSE） and the PSNR, while the degree of closeness between them is evaluated using the normalized cross correlation（NCC）. The experimental results show that, the proposed algorithms can hide the secret text with a large payload capacity with a high level of security and a higher invisibility. Furthermore, the proposed technique is computationally efficient and better results for both PSNR and NCC are achieved compared with the previous algorithms.

关键词： image steganography image processing integer wavelet transform

Physical and economic impacts of studded tyre use on pavement structures in cold climates

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Transportation Safety and Environment 2021年第4期3卷 100-114页

作者： osama A.Abaza Mahmoud Arafat Muhammad Saif Uddin Department of Civil Engineering University of Alaska Anchorage2900 Spirit DriveEIB 301 LAnchorageAlaska 99508USA Department of Civil and Environmental Engineering Florida International University10555 West Flagler StreetEC 3730MiamiFL 33174USA

In cold regions like Alaska of USA,Canada and the northern parts of Europe,using studded tyres is common among the public when driving in icy and snowy ***,studded tyres cause extensive wear to asphalt pavement,reducing pavement *** study addresses the physical and economic impacts of winter studded tyres on the roadway system to better inform decision makers as they develop alternative solutions and future *** approach is applied in a case study from a sample of Alaska statewide road *** were employed to examine the extent of the use of studded tyres and cost-effective alternatives.A pavement life-cycle cost review was established considering several variables to discover a realistic cost of roadway resurfacing and *** rates due to studded tyres and rut rates due to wheel loads were found for different highway *** results indicate higher average wear rates due to studded passenger vehicles on freeways than average rut rates due to heavy wheel *** results also indicate lower average wear rates on arterial and collector *** estimates show that studded tyre use reduced asphalt surface life by about 7 years on the selected freeway sample in the case study,which is about 47%loss in pavement life based on the initial design life of 15 *** road classes experienced lower reductions in service ***,cost analysis was provided to reflect the impact of studded tyres on the state’s *** were suggested,which in turn may help other cold regions develop strategies on the use of new winter tyre technology.

关键词： wear rate pavement rutting studded tyre winter tyre technology economic analysis

A Storage Optimization Scheme for Blockchain Transaction Databases

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Computer Systems Science & Engineering 2021年第3期36卷 521-535页

作者： Jingyu Zhang Siqi Zhong Jin Wang Xiaofeng Yu osama Alfarraj School of Computer and Communication Engineering Changsha University of Science and TechnologyChangsha410114China School of Systems Engineering National University of Defense TechnologyChangsha410000China School of Information Science and Engineering Fujian University of TechnologyFuzhou350000China School of Business Nanjing UniversityNanjing210093China Computer Science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia

As the typical peer-to-peer distributed networks, blockchain systemsrequire each node to copy a complete transaction database, so as to ensure newtransactions can by verified independently. In a blockchain system (e.g., bitcoinsystem), the node does not rely on any central organization, and every node keepsan entire copy of the transaction database. However, this feature determines thatthe size of blockchain transaction database is growing rapidly. Therefore, with thecontinuous system operations, the node memory also needs to be expanded tosupport the system running. Especially in the big data era, the increasing networktraffic will lead to faster transaction growth rate. This paper analyzes blockchaintransaction databases and proposes a storage optimization scheme. The proposedscheme divides blockchain transaction database into cold zone and hot zone usingexpiration recognition method based on Least Recently Used (LRU) algorithm. Itcan achieve storage optimization by moving unspent transaction outputs outsidethe in-memory transaction databases. We present the theoretical analysis on theoptimization method to validate the effectiveness. Extensive experiments showour proposed method outperforms the current mechanism for the blockchaintransaction databases.

关键词： Blockchain distributed systems transaction databases

Lymphocytic colitis: A clue to bacterial etiology

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World Journal of Gastroenterology 2005年第46期11卷 7266-7271页

作者： Thanaa EA Helal Naglaa S Ahmed osama Abo El Fotoh Department of PathologyFaculty of Medicine Ain Shams UniversityEgypt Department of Internal MedicineFaculty of Medicine Ain Shams UniversityEgypt

AIM： To find out the role of bacteria as a possible etiological factor in lymphocytic colitis. METHODS： Twenty patients with histopathological diagnosis of lymphocytic colitis and 10 normal controls were included in this study. Colonoscopic biopsies were obtained from three sites （hepatic and splenic flexures and rectosigmoid region）. Each biopsy was divided into two parts. A fresh part was incubated on special cultures for bacterial growth. The other part was used for the preparation of histologic tissue sections that were examined for the presence of bacteria with the help of Giemsa stain. RESULTS： Culture of tissue biopsies revealed bacterial growth in 18 out of 20 patients with lymphocytic colitis mostly Escherichia coil （14/18）, which was found in all rectosigmoid specimens （14/14）, but only in 8/14 and 6/14 of splenic and hepatic flexure specimens respectively. In two of these cases, E coli was associated with proteus. Proteus was found only in one case, Klebsiella in two cases, and Staphylococcus aureus in one case. In the control group, only 2 out of 10 controls showed the growth of E coli in their biopsy cultures. Histopathology showed rod-shaped bacilli in the tissue sections of 12 out of 14 cases with positive E coli in their specimen＇s culture. None of the controls showed these bacteria in histopathological sections. CONCLUSION： This preliminary study reports an association between E coli and lymphocytic colitis, based on histological and culture observations. Serotyping and molecular studies are in process to assess the role of E coli in the pathogenesis of lymphocytic colitis.

关键词： Lymphocytic colitis E coli Histopathology Culture

Road scene analysis for determination of road traffic density

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Frontiers of Computer Science 2014年第4期8卷 619-628页

作者： Omar AL-KADI osama AL-KADI Rizik AL-SAYYED Ja'far ALQATAWNA King Abdullah lI School for Information Technology University of Jordan Amman 11942 Jordan College of Engineering and Computer Science Australian National University Canberra ACT 0200 Australia

Road traffic density has always been a concern in large cities around the world, and many approaches were developed to assist in solving congestions related to slow traffic flow. This work proposes a congestion rate estimation approach that relies on real-time video scenes of road traffic, and was implemented and evaluated on eight different hotspots covering 33 different urban roads. The approach relies on road scene morphology for estimation of vehicles average speed along with measuring the overall video scenes randomness acting as a frame texture analysis indicator. Experimental results shows the feasibility of the proposed approach in reliably estimating traffic density and in providing an early warning to drivers on road conditions, thereby mitigating the negative effect of slow traffic flow on their daily lives.

关键词： road congestion image texture local binary pattern scene morphology

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

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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