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Big Data Analytics Using Graph Signal Processing

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Computers, Materials & Continua 2023年第1期74卷 489-502页

作者： Farhan Amin omar M.Barukab Gyu Sang Choi Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea Faculty of Computing and Information Technology-Rabigh King Abdulaziz UniversityJeddahSaudi Arabia

The networks are fundamental to our modern world and they appear throughout science and *** to a massive amount of data presents a unique opportunity to the researcher’s *** networks grow in size the complexity increases and our ability to analyze them using the current state of the art is at severe risk of failing to keep ***,this paper initiates a discussion on graph signal processing for large-scale data *** first provide a comprehensive overview of core ideas in Graph signal processing(GSP)and their connection to conventional digital signal processing(DSP).We then summarize recent developments in developing basic GSP tools,including methods for graph filtering or graph learning,graph signal,graph Fourier transform(GFT),spectrum,graph frequency,*** filtering is a basic task that allows for isolating the contribution of individual frequencies and therefore enables the removal of *** then consider a graph filter as a model that helps to extend the application of GSP methods to large *** show the suitability and the effeteness,we first created a noisy graph signal and then applied it to the *** several rounds of simulation *** see that the filtered signal appears to be smoother and is closer to the original noise-free distance-based *** using this example application,we thoroughly demonstrated that graph filtration is efficient for big data analytics.

关键词： Big data data science big data processing graph signal processing social networks

Contralateral eye study of refractive,topographic and aberrometric outcomes after femtosecond assisted Myo Ring implantation and DALK for management of keratoconus

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International Journal of Ophthalmology(English edition) 2018年第10期11卷 1621-1630页

作者： Mohamed omar Yousif Azza Mohamed Ahmed Said Department of Ophthalmology Faculty of Medicine Ain Shams University

AIM：To evaluate the efficacy of femtosecond laser assisted MyoRing intrastromal corneal implant and deep anterior lamellar keratoplasty （DALK） for management of moderate to advanced keratoconus regarding the degree of changes in visual acuity, refraction, corneal asphericity and ***：A prospective non comparative interventional case study was conducted in Ophthalmology Department,Ain Shams University Hospital in the period from January 2015 to February 2017. The study included 30 eyes of moderate to advanced keratoconus. MyoRing was implanted in one eye （Group Ⅰ） and DALK operation was performed in the contralateral eye of the same patient （Group Ⅱ）.Preoperative and 6mo post-operative uncorrected visual acuity（UCVA）, corrected distance visual acuity （CDVA）, spherical equivalent （SE）, corneal and refractive astigmatisms,keratometry and Q-value using topography images were acquired. Quality of vision was assessed in all eyes including total corneal, anterior corneal high order aberrations analysis at 5 mm pupil size and the Strehl ratio of point spread function （PSF） as an objective measure of ***：Mean postoperative UCVA, CDVA, SE, refractive astigmatism,keratometryreadingsandasphericity were statistically improved compared to preoperative parameters in both groups （P〈0.05）. Significant reduction of all corneal aberrations following both techniques（P〈0.05） was achieved except mean trefoil and mean PSF in Group Ⅰ （P〉0.05）. Postoperative corneal aberrations were significantly lower in Group Ⅱ compared to Group Ⅰ.A statistically significant negative correlation was found in Group Ⅰ between the mean change in CDVA （logMAR）and the mean preoperative and mean postoperative total corneal aberrations root mean square （RMS; r=-0.78,P=0.04）. Also a statistically significant negative correlation was found between mean preoperative coma RMS and mean post PSF （r=-0.86, P=0.01）. In Group Ⅱ, there was a statistically significant positive correlation between m

关键词： aberrations deep anterior lamellar keratoplasty femtosecond laser keratoconus MyoRing

Aspect-Oriented Modeling and Verification with Finite State Machines

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Journal of Computer Science & Technology 2009年第5期24卷 949-961页

作者：徐殿祥 omar El-Ariss 许巍峰王林章 National Center for the Protection of the Financial Infrastructure Dakota State UniversityMadisonSD 57042 U.S.A. State Key Laboratory of Novel Software Technology Department of Computer Science and TechnologyNanjing University Department of Computer Science North Dakota State UniversityFargoND 58105 U.S.A Computer and Information Science Department Gannon University109 University SquareEriePA 16541 U.S.A

Aspect-oriented programming modularizes crosscutting concerns into aspects with the advice invoked at the specified points of program execution. Aspects can be used in a harmful way that invalidates desired properties and even destroys the conceptual integrity of programs. To assure the quality of an aspect-oriented system, rigorous analysis and design of aspects are highly desirable. In this paper, we present an approach to aspect-oriented modeling and verification with finite state machines. Our approach provides explicit notations （e.g., pointcut, advice and aspect） for capturing crosscutting concerns and incremental modification requirements with respect to class state models. For verification purposes, we compose the aspect models and class models in an aspect-oriented model through a weaving mechanism. Then we transform the woven models and the class models not affected by the aspects into FSP （Finite State Processes）, which are to be checked by the LTSA （Labeled Transition System Analyzer） model checker against the desired system properties. We have applied our approach to the modeling and verification of three aspect-oriented systems. To further evaluate the effectiveness of verification, we created a large number of flawed aspect models and verified them against the system requirements. The results show that the verification has revealed all flawed models. This indicates that our approach is effective in quality assurance of aspect-oriented state models. As such, our approach can be used for model-checking state-based specification of aspect-oriented design and can uncover some system design problems before the system is implemented.

关键词： aspect-oriented modeling finite state machines modeling verification model checking

Optoelectronic devices informatics: optimizing DSSC performance using random-forest machine learning algorithm

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Optoelectronics Letters 2022年第3期18卷 148-151页

作者： omar Al-Sabana Sameh O.Abdellatif Electrical Engineering Department Faculty of Engineering and FabLab in the Centre for Emerging Learning Technology(CELT)The British University in EgyptCairo 11387Egypt

This paper provides an attempt to utilize machine learning algorithm,explicitly random-forest algorithm,to optimize the performance of dye sensitized solar cells(DSSCs)in terms of conversion *** optimization is implemented with respect to both the mesoporous TiO_(2) active layer thickness and ***,the porosity impact is reflected to the model as a variation in the effective refractive index and dye *** set has been established using our data in the literature as well as numerical data extracted from our numerical *** random-forest model is used for model regression,prediction,and optimization,reaching 99.87%*** agreement with experimental data was observed,with 4.17%conversion efficiency.

关键词： porosity performance algorithm

A scalable blockchain-based scheme for traffic-related data sharing in VANETs

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Blockchain(Research and Applications) 2022年第3期3卷 109-121页

作者： El-hacen Diallo omar Dib Khaldoun Al Agha UniversitéParis-Saclay CNRSLaboratoire Interdisciplinaire des Sciences du Numérique91190Gif-sur-YvetteFrance Department of Computer Science Wenzhou-Kean UniversityWenzhou325015China

Recent advances in wireless technology and embedded systems enable vehicles to share relevant traffic-related data to improve the transportation Quality-of-Service(QoS).However,due to the ubiquitousness of cyber-attacks,it is challenging to ensure the integrity of the data collected from *** paper proposes a novel architecture for road traffic events management in Vehicular Ad hoc NETworks(VANETs)relying on a permissioned *** also introduces the concept of micro-transactions to minimize communication and storage *** simulations,a rigorous performance evaluation of the proposed approach was conducted,and the micro-transactions effectiveness was *** addition,a comparison with close works in the literature was *** proposed scheme ensures road traffic records integrity and traceability,and simulation results on the considered scenarios showed good performance.

关键词： Vehicular ad hoc NETworks(VANETs) Blockchain Consensus mechanisms Practical byzantine fault tolerance(PBFT) Data sharing

Lymphangiogenesis:A new player in cancer progression

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World Journal of Gastroenterology 2010年第32期16卷 4003-4012页

作者： Masayuki Nagahashi Subramaniam Ramachandran omar M Rashid Kazuaki Takabe Division of Surgical Oncology Department of SurgeryVirginia Commonwealth University School of Medicine and Massey Cancer CenterRichmondVA 23298-0011United States

Lymph node metastasis is the hallmark of colon cancer progression,and is considered one of the most important prognostic ***,there has been growing evidence that tumor lymphangiogenesis(formation of new lymphatic vessels) plays an important role in this ***,we review the latest f indings of the role of lymphangiogenesis in colorectal cancer progression,and discuss its clinical application as a biomarker and target for new *** the molecular pathways that regulate lymphangiogenesis is mandatory to pave the way for the development of new therapies for *** the future,tailored treatments consisting of combinations of chemotherapy,other targeted therapies,and anti-lymphangiogenesis agents will hopefully improve patient *** progression to the clinic must be guided by new avenues of research,such as the identif ication of biomarkers that predict response to treatment.

关键词： Colorectal neoplasms Angiogenesis Lymphangiogenesis Lymphatic vessels Lymphatic metastasis Vascular endothelial growth factor Monoclonal antibody D2-40 Therapy-related neoplasms Biomarkers

Space-Fractional Diffusion with Variable Order and Diffusivity:Discretization and Direct Solution Strategies

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Communications on Applied Mathematics and Computation 2022年第4期4卷 1416-1440页

作者： Hasnaa Alzahrani George Turkiyyah omar Knio David Keyes King Abdullah University of Science and Technology ThuwalSaudi Arabia

We consider the multidimensional space-fractional diffusion equations with spatially varying diffusivity and fractional *** computational challenges are encoun-tered when solving these equations due to the kernel singularity in the fractional integral operator and the resulting dense discretized operators,which quickly become prohibitively expensive to handle because of their memory and arithmetic *** this work,we present a singularity-aware discretization scheme that regularizes the singular integrals through a singularity subtraction technique adapted to the spatial variability of diffusiv-ity and fractional *** regularization strategy is conveniently formulated as a sparse matrix correction that is added to the dense operator,and is applicable to different formula-tions of fractional diffusion *** also present a block low rank representation to handle the dense matrix representations,by exploiting the ability to approximate blocks of the resulting formally dense matrix by low rank factorizations.A Cholesky factorization solver operates directly on this representation using the low rank blocks as its atomic com-putational tiles,and achieves high performance on multicore *** results show that the singularity treatment is robust,substantially reduces discretization errors,and attains the first-order convergence rate allowed by the regularity of the *** also show that considerable savings are obtained in storage(O(N^(1.5)))and computational cost(O(N^(2)))compared to dense *** translates to orders-of-magnitude savings in memory and time on multidimensional problems,and shows that the proposed methods offer practical tools for tackling large nonlocal fractional diffusion simulations.

关键词： Fractional diffusion Variable order Variable diffusivity Singularity subtraction Block low rank matrix Tile low rank(TLR)Cholesky

True grit: ingestion of small stone particles by hummingbirds in West Mexico

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Avian Research 2021年第4期12卷 739-749页

作者： omar Maya-García Mauricio Ortega-Flores Jorge E.Schondube Posgrado en Ciencias Biológicas Unidad de PosgradoCoordinación del Posgrado en Ciencias BiológicasUniversidad Nacional Autónoma de MéxicoEdificio D1er pisoCircuito de PosgradosCiudad UniversitariaDel.CoyoacánC.P.04510 México D.F.Mexico Laboratorio de Ecología Funcional Instituto de Investigaciones en Ecosistemas y SustentabilidadUniversidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro No.8701Col.Ex Hacienda de San Joséde la HuertaC.P.58190 MoreliaMichoacánMexico

Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and *** feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West ***: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear Colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird Selasphorus platycercus, and Rufous Hummingbird S. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin ***: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican ***: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;how

关键词： Arthropod chitin content Arthropod digestion Breeding season Mineral nutritional requirements

Neutronic study on the effect of first wall material thickness on tritium production and material damage in a fusion reactor

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Nuclear Science and Techniques 2022年第4期33卷 33-50页

作者： HacıMehmet S¸ahin Güven Tunc¸ Alper Karakoc¸ Melood Mohamad omar Department of Energy Systems Engineering Technology FacultyKarabuk UniversityKarabukTurkey Department of Energy Systems Engineering Technology FacultyGazi UniversityAnkaraTurkey Department of Energy Systems Engineering Institute of Graduate ProgramsKarabuk UniversityKarabukTurkey

In this study,the effects of changing first wall materials and their thicknesses on a reactor were investigated to determine the displacement per atom(DPA)and gas production(helium and hydrogen)in the first wall,as well as the tritium breeding ratio(TBR)in the coolant and tritium breeding ***,the modeling of the magnetic fusion reactor was determined based on the blanket parameters of the International Thermonuclear Experimental Reactor(ITER).Stainless steel(SS 316 LNIG),Oxide Dispersion Strengthened Steel alloy(PM2000 ODS),and China low-activation martensitic steel(CLAM)were used as the first wall(FW)*** family molten salt materials(FLiBe,FLiNaBe,FLiPb)and lithium oxide(LiO_(2))were considered the coolant and tritium production material in the blanket,*** transport calculations were performed using the wellknown 3D code MCNP5 using the continuous-energy Monte Carlo *** built-in continuous energy nuclear and atomic data libraries along with the Evaluated Nuclear Data file(ENDF)system(ENDF/B-V and ENDF/B-VI)were ***,the activity cross-section data library CLAW-IV was used to evaluate both the DPA values and gas production of the first wall(FW)*** interface computer program written in the FORTRAN 90 language to evaluate the MCNP5 outputs was developed for the fusion reactor *** results indicated that the best TBR value was obtained for the use of the FLiPb coolant,whereas depending on the thickness,the first wall replacement period in terms of radiation damage to all materials was between 6 and 11 years.

关键词： ITER First wall material Material damage Tritium breeding ratio Fluorides family molten salt materials