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International Journal of Ophthalmology(English edition) 2020年第1期13卷 129-134页

作者： Amr Mounir Engy Mohamed Mostafa hatem ammar Osama Ali Mohammed Alahmady Hamad Alsmman Mahmoud Mohamed Farouk Mohamed Gamal Elghobaier Department of Ophthalmology Sohag Faculty of MedicineSohag UniversitySohag 82524Egypt Egyptian Police Hospitals Cairo 11765Egypt

AIM: To evaluate the safety and efficacy of transepithelial photorefractive keratectomy(t-PRK) with adjuvant mitomycin C(MMC) versus femtosecond laser assisted keratomileusis(Femto-LASIK) in correction of high ***: Prospective randomized comparative study including 156 eyes of 156 patients with high myopia and a spherical equivalent refraction(SER) <-6.00 D. They were divided randomly into two groups: Group A included 72 eyes treated with t-PRK with adjuvant MMC and Group B included 84 eyes treated with Femto-LASIK. Visual acuity, SER, corneal topography, pachymetry and keratometry were assessed for 12 mo ***: The preoperative mean SER was-8.86±1.81 and-9.25±1.70 D in t-PRK MMC group and Femto-LASIK respectively(P=0.99) which improved to-0.65±0.43 D and-0.69±0.50 D at 12 mo follow up. Mean SER remained stable during the 12 mo of follow-up, with no statistically significant difference between the two groups(P=0.64). In t-PRK MMC group, only six eyes needed retreatment after six months of follow up. And two eyes showed haze(one reversible haze grade 2, while the other had dense irreversible haze grade 4).CONCLUSION: t-PRK MMC provides safe and satisfactory visual outcomes and acceptable risk as Femto-LASIK in patients with high myopia.

关键词： transepithelial photorefractive keratectomy femtosecond laser assisted keratomileusis high myopia corneal haze Egypt

Effects of Depression of Water Level in the Euphrates River in Iraq on the Operation of AI-Anbar Thermal Power Station

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Journal of Civil Engineering and Architecture 2013年第3期7卷 350-363页

作者： ammar hatem Kamel Issam Mohammed Ayad Sulaiby Mustaffa College of Engineering University of Anbar Ramadi 31003 Iraq

Increase in demand of electrical power for different purposes in Iraq leads increase towards to power plant system such as thermal power plant. Any thermal power plant requires water for processing, cooling, oilfields, boiler feed and other miscellaneous uses including domestic requirements. The main parameter to measure the efficiency of thermal power plant is the availability of water and technology employed. Therefore, the thermal power plants like A1-Anbar thermal power station is built on the Euphrates River bank in the city of Ramadi in the middle part of Iraq. Depending on the field measurements and pervious measurements, the computation of river water level for different frequency periods was achieved to determine the inundation area of the plant and the required height of power plant intakes. The problems of intake operation include low flow rate of the river at intake that resulting low water level （minimum flow rate was recorded 107 m^3/s with water level 47.8 m）, and annual sediments at intake that may be caused operation off. Therefore, any design for the intake or operation must consider the above problems. The study referred to the discharge for full operation is about 300 m^3/s and water level is 51.3 m to satisfy these requirements. The study suggested two solutions for this problem, first by using the groins and the second by building two weirs.

关键词： Thermal power station hydrologic study intake structure.

Investigation of Physical and Numerical Model of Archimedes Screw Turbine

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Journal of Power and Energy Engineering 2020年第10期8卷 26-42页

作者： Omar Sulaiman Abdullah Wissam Hashim Khalil ammar hatem Kamel Amir J. Shareef Dams & Water Resources Engineering Department Engineering College University of Anbar Ramadi Iraq Renewable Energy Research Center University of Anbar Ramadi Iraq

Archimedes screw turbines have been developed as they work with a low head with high efficiency, where flow energy can be exploited in small rivers, streams, regulators and others. The power can be produced using Archimedes turbines and depends on some parameters including the number of blades, flow, and angle of the shaft inclination and the length of the pitch. A physical and numerical model has been developed to determine the performance of the Archimedes turbine on the Ramadi Dam in Iraq. The physical model was made of stainless steel with the following parameters (length 1000 mm, pitch 70 mm, diameter ratio 0.536, inclination angles 30°, 35°, 40°, 45°). Work was carried out on different flow rates and inclination angles. The experimental results showed that the highest efficiency was 81.4% at 35° inclination angle and a flow rate of 1.12 l/s; the maximum power of 9.03 watts was at a 45° inclination angle and a flow rate of 2.065 l/s and 72% efficiency. Also, the impact of the pitch and the number of blades were studied. The results show that torque is increase with

关键词： Archimedes Screw Turbine Physical Model Small Hydropower Station CFD Low Head Turbine

Mechanical behaviour of fiber-reinforced grout in rock bolt reinforcement

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 437-453页

作者： Yingchun Li ammar Ahmed Danqi Li Deep Underground Engineering Research Center Dalian University of TechnologyDalian116024China WA School of Mines:Minerals Energy and Chemical Engineering Curtin UniversityKalgoorlieWA6430Australia

Grouted rock bolts subject to axial loading in the field exhibit various failure modes,among which the most predominant one is the bolt-grout interface ***,mechanical characterization of the grout is essential for understanding its performance in ground *** date,few studies have been conducted to characterize the mechanical behaviour of fiber-reinforced grout(FRG)in rock bolt *** we experimentally studied the mechanical behaviour of FRG under uniaxial compression,indirect tension,and direct shear loading *** also conducted a series of pullout tests of rebar bolt encapsulated with different grouts including conventional cementitious grout and *** was developed using 15%silica fume(SF)replacement of cement(by weight)and steel fiber to achieve highstrength and crack-resistance to overcome drawbacks of the conventional *** types of steel fibers including straight and wavy steel fibers were further added to enhance the grout *** effect of fiber shape and fiber volume proportion on the grout mechanical properties were *** experimental results showed that the addition of SF and steel fiber by 1.5%fiber volume proportion could lead to the highest compressive,tensile,and shear strengths of the *** minimum volume of fiber that could improve the mechanical properties of grout was found at 0.5%.The scanning electron microscopy(SEM)analysis demonstrated that steel fibers act as an excellent bridge to prevent the cracks from propagating at the interfacial region and hence to aid in maintaining the integrity of the cementitious *** laboratory pullout tests further confirmed that FRG could prevent the cylindrical grout annulus from radial crack and hence improve the rebar’s load carrying ***,FRG has a potential to be utilized in civil and mining applications where high-strength and crack-resistance support is required.

关键词： Fiber-reinforced grout(FRG) Steel fibers Mechanical properties Direct shear test Pullout test

Modern Mobile Malware Detection Framework Using Machine Learning and Random Forest Algorithm

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Computer Systems Science & Engineering 2024年第5期48卷 1171-1191页

作者： Mohammad Ababneh Ayat Al-Droos ammar El-Hassan School of Computing Sciences Princess Sumaya University for TechnologyAmman11941Jordan

With the high level of proliferation of connected mobile devices,the risk of intrusion becomes *** Intelligence(AI)and Machine Learning(ML)algorithms started to feature in protection software and showed effective *** algorithms are nonetheless hindered by the lack of rich datasets and compounded by the appearance of new categories of malware such that the race between attackers’malware,especially with the assistance of Artificial Intelligence tools and protection solutions makes these systems and frameworks lose effectiveness *** this article,we present a framework for mobile malware detection based on a new dataset containing new categories of mobile *** focus on categories of malware that were not tested before by Machine Learning algorithms proven effective in malware *** carefully select an optimal number of features,do necessary preprocessing,and then apply Machine Learning algorithms to discover malicious code *** our experiments,we have found that the Random Forest algorithm is the best-performing algorithm with such mobile malware with detection rates of around 99%.We compared our results from this work and found that they are aligned well with our previous *** also compared our work with State-of-the-Art works of others and found that the results are very close and competitive.

关键词： Android malware detect prevent artificial intelligence machine learning mobile CICMalDroid2020 CCCSCIC-AndMal-2020

Investigating and predicting the role of photovoltaic, wind, and hydrogen energies in sustainable global energy evolution

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Global Energy Interconnection 2024年第4期7卷 429-445页

作者： Mahmood Swadi Dheyaa Jasim Kadhim Mohamed Salem Firas Mohammed Tuaimah ammar Sabri Majeed Ali Jawad Alrubaie Department of Electrical Engineering College of EngineeringUniversity of BaghdadBaghdad 10001Iraq Libyan Authority for Scientific Research Tripoli 80045Libya School of Electrical and Electronic Engineering Universiti Sains Malaysia(USM)Nibong Tebal 14300PenangMalaysia Continuing Education Center University of BaghdadBaghdad 10001Iraq Al-Furat Al-Awsat Technical University AL-Mussaib Technical CollegeBabylonIraq

The global shift toward next-generation energy systems is propelled by the urgent need to combat climate change and the dwindling supply of fossil *** review explores the intricate challenges and opportunities for transitioning to sustainable renewable energy sources such as solar,wind,and *** transition economically challenges traditional energy sectors while fostering new industries,promoting job growth,and sustainable economic *** transition to renewable energy demands social equity,ensuring universal access to affordable energy,and considering community *** environmental benefits include a significant reduction in greenhouse gas emissions and a lesser ecological *** study highlights the rapid growth of the global wind power market,which is projected to increase from$112.23 billion in 2022 to$278.43 billion by 2030,with a compound annual growth rate of 13.67%.In addition,the demand for hydrogen is expected to increase,significantly impacting the market with potential cost reductions and making it a critical renewable energy source owing to its affordability and zero *** 2028,renewables are predicted to account for 42%of global electricity generation,with significant contributions from wind and solar photovoltaic(PV)technology,particularly in China,the European Union,the United States,and *** developments signify a global commitment to diversifying energy sources,reducing emissions,and moving toward cleaner and more sustainable energy *** review offers stakeholders the insights required to smoothly transition to sustainable energy,setting the stage for a resilient future.

关键词： Next energy Renewable energy Sustainability Environmental benefits Economic opportunities

Tribological behavior of shape-specific microplate-enriched synovial fluids on a linear two-axis tribometer

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Friction 2024年第3期12卷 539-553页

作者： Agnese FRAGASSI Antonietta GRECO Martina DI FRANCESCO Luca CESERACCIU Aiman ABU ammar Israel DVIR Thomas Lee MOORE Haytam KASEM Paolo DECUZZI Laboratory of Nanotechnology for Precision Medicine Fondazione Istituto Italiano di TecnologiaGenova 16163Italy Department of Chemistry and Industrial Chemistry University of GenovaGenoa 16146Italy Materials Characterization Facility Istituto Italiano di TecnologiaGenova 16163Italy Department of Pharmaceutical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel Department of Mechanical Engineering Azrieli College of Engineering JerusalemJerusalem 9103501Israel

Nano-and micro-particles are being increasingly used to tune interfacial frictional properties in diverse applications,from friction modifiers in industrial lubrication to enhanced biological fluids in human osteoarthritic ***,we assessed the tribological properties of a simulated synovial fluid enriched with non-spherical,poly lactic-co-glycolic acid(PLGA)microparticles(μPL)that have been previously demonstrated for the pharmacological management of osteoarthritis(OA).Three different μPL configurations were fabricated presenting a 20μm×20μm square base and a thickness of 5μm(thin,5H μPL),10μm(10H μPL),and 20μm(cubical,20H μPL).After extensive morphological and physicochemical characterizations,the apparent Young’s modulus of the μPL was quantified under compressive loading returning an average value of~6 kPa,independently of the particle ***,using a linear two-axis tribometer,the static(μ_(s))and dynamic(μ_(d))friction coefficients of the μPL-enriched simulated synovial fluid were determined in terms of particle configuration and concentration,varying from 0(fluid only)to 6×10^(5) μPL/*** particle morphology had a modest influence on friction,possibly because the μPL were fully squeezed between two mating surfaces by a 5.8 N normal load realizing boundary-like lubrication ***,friction was observed to depend on the dimensionless parameterW,defined as the ratio between the total volume of the μPL enriching the simulated synovial fluid and the volume of the fluid *** coefficients of friction were documented to grow withWreaching a plateau of μ_(s)~0.4 and μ_(d)~0.15,already at Ω~2×10^(-3).Future investigations will have to systematically analyze the effect of sliding velocity,normal load,and rigidity of the mating surfaces to elucidate in full the tribological behavior of μPL in the context of osteoarthritis.

关键词： osteoarthritis microparticles tribology synovial fluid pin on plate

Analysis and Control of the Vehicle Roll Dynamics Using Sum of Squares Polynomial Approach

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Journal of Systems Science & Complexity 2024年

作者： IBEN ammar Imen DOUMIATI Moustapha TALJ Reine CHOKOR Abbas MACHMOUM Mohamed ESEO-IREENA Institut de Recherche en énergie électrique de Nantes Atlantique IREENA UR 4642 37 Boulevard de l’Université-BP406 Sorbonne Universités Université de Technologie de Compiègne CNRS Institut de Recherche en énergie électrique de Nantes Atlantique IREENA UR 4642 37 Boulevard de l’Université-BP 406

The safety of vehicle travel relies on good stability performance, making vehicle motion control a vital technology in vehicles. This paper focuses on investigating the impact of roll control on vehicle performance, particularly in terms of avoiding rollover and ensuring lateral stability. By introducing a feedback roll moment, the roll motion can be effectively controlled. The paper considers two roll reference generators: A static one aimed at zero roll, and a dynamic one based on the vehicle's lateral acceleration. The static roll reference generator enhances stability by employing a fixed reference, particularly beneficial during routine driving conditions. In contrast, the dynamic roll reference generator continually adapts the roll angle reference in response to real-time vehicle dynamics and driving conditions. These proposed reference generators can be paired with varying suspension systems — Static reference could be achieved using semi-active suspensions, while the dynamic one is integrated into advanced active suspension systems, offering heightened adaptability and *** address the roll control objectives, this paper proposes a novel sum of squares(SOS) integral polynomial tracking control. The proposed controller satisfies control bounds and considers control constraints during the design phase. The effectiveness and robustness of the proposed control scheme are evaluated through numerical simulations using a full vehicle nonlinear model in Matlab/Simulink. The results of these simulations are compared to super-twisting sliding mode and Lyapunov-based controllers.

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Prevalence and associated factors of clubfoot in the eastern province of Saudi Arabia: A hospital-based study

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World Journal of Orthopedics 2024年第7期15卷 635-641页

作者： ammar K Alomran Bandar A Alzahrani Bader S Alanazi Mohammed A Alharbi Loay M Bojubara Eman M Alyaseen Department of Orthopedic College of MedicineImam Abdulrahman bin Faisal UniversityDammam 34212Saudi Arabia College of Medicine Imam Abdulrahman bin Faisal UniversityDammam 34212Saudi Arabia College of Medicine Arabian Gulf UniversityManama 329Bahrain

BACKGROUND Clubfoot,or congenital talipes equinovarus,is a widely recognized cause of disability and congenital deformity worldwide,which significantly impacts the quality of *** management of clubfoot requires long-term,multidiscip-linary *** is important to understand how common this condition is in order to assess its impact on the ***,few studies have investigated the prevalence of clubfoot in Saudi *** To determine the prevalence of clubfoot in Saudi Arabia via the patient population at King Fahad University Hospital(KFUH).METHODS This was a retrospective study conducted at one of the largest hospitals in the country and located in one of the most densely populated of the administrative *** Of the 7792 births between 2015 to 2023 that were included in the analysis,42 patients were diagnosed with clubfoot,resulting in a prevalence of 5.3 per 1000 live births at *** The observed prevalence of clubfoot was significantly higher than both global and local estimates,indicating a substantial burden in the study population.

关键词： Clubfoot Talipes equinovarus Congenital talipes equinovarus Prevalence Saudi Arabia

Parallel Inference for Real-Time Machine Learning Applications

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Journal of Computer and Communications 2024年第1期12卷 139-146页

作者： Sultan Al Bayyat ammar Alomran Mohsen Alshatti Ahmed Almousa Rayyan Almousa Yasir Alguwaifli College of Computer Science and Information Technology Imam Abdulrahman Bin Faisal University Dammam Saudi Arabia

Hyperparameter tuning is a key step in developing high-performing machine learning models, but searching large hyperparameter spaces requires extensive computation using standard sequential methods. This work analyzes the performance gains from parallel versus sequential hyperparameter optimization. Using scikit-learn’s Randomized SearchCV, this project tuned a Random Forest classifier for fake news detection via randomized grid search. Setting n_jobs to -1 enabled full parallelization across CPU cores. Results show the parallel implementation achieved over 5× faster CPU times and 3× faster total run times compared to sequential tuning. However, test accuracy slightly dropped from 99.26% sequentially to 99.15% with parallelism, indicating a trade-off between evaluation efficiency and model performance. Still, the significant computational gains allow more extensive hyperparameter exploration within reasonable timeframes, outweighing the small accuracy decrease. Further analysis could better quantify this trade-off across different models, tuning techniques, tasks, and hardware.

关键词： Machine Learning Models Computational Efficiency Parallel Computing Systems Random Forest Inference Hyperparameter Tuning Python Frameworks (TensorFlow PyTorch Scikit-Learn) High-Performance Computing