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Characteristic time scale as optimal input in Machine Learning algorithms:homogeneous autoignition

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Energy and AI 2023年第4期14卷 238-252页

作者： mohammed I.Radaideh Stelios Rigopoulos Dimitris A.Goussis Department of Mechanical Engineering Khalifa University of Science and TechnologyAbu Dhabi 127788United Arab Emirates Imperial College London Mechanical Engineering South Kensington Campus London SW72AZUnited Kingdom Research and Innovation Center on CO_(2)and h_(2) Khalifa University of Science and TechnologyAbu Dhabip127788United Arab Emirates

Considering temporally evolving processes,the search for optimal input selection in Machine Learning(ML)algorithms is extended here beyond(i)the readily available independent variables defining the process and(ii)the dependent variables suggested by feature extraction methods,by considering the time scale that characterizes the *** analysis is based on the process of homogeneous autoignition,which is fully determined by the initial temperature T(0)and pressure p(0)of the mixture and the equivalence ratio𝜙that specifies the initial mixture *** aim is to seek the optimal input for the prediction of the time at which the mixture *** Multilayer Perceptron(MLP)and Principal Component Analysis(PCA)algorithms are employed for prediction and feature extraction,*** is demonstrated that the time scale that characterizes the initiation of the process𝜐𝑓(0),provides much better accuracy as input to MLP than any pair of the three independent parameters T(0),p(0)and𝜙or their two principal ***,it is shown that using𝜐𝑓(0)as input results in a coefficient of determination R 2 in the range of 0.953 to 0.982,while the maximum value of R 2 when using the independent parameters or principal components is *** physical grounds,on which the success of𝜐𝑓(0)is based,are *** results suggest the need for further research in order to develop selection methodologies of optimal inputs among those that characterize the process.

关键词： Machine Learning Feature selection Autoignition

Numerical Simulation of a Granular Flow on a Smooth Inclined Plane

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Fluid Dynamics & Materials Processing 2022年第6期18卷 1631-1638页

作者： Rida Tazi Adil Echchelh mohammed El Ganaoui Aouatif Saad Laboratory of Materials and Energy Faculty of SciencesIbn Tofail UniversityKenitraMorocco LERMAB/IUT Longwy Institut CarnotNancyFrance ASELab Advanced Systems Engineering Laboratory National School of Applied SciencesIbn Tofail UniversityKenitraMorocco

Unlike most fluids,granular materials include coexisting solid,liquid or gaseous regions,which produce a rich variety of complex *** flows of grains driven by gravity down inclines occur in nature and in *** describe the granular flow on an inclined surface,several studies were carried *** can cite in particular the description of Saint-Venant which considers a dry granular flow,without cohesion and it only takes into account the substance-substrate friction,this model proposes a simplified form of the granular flow,which depends on the one side on the angle of inclination of the substrate with respect to the horizontal plane and on the other side on the thickness of the substance *** numerical simulation we have developed is first based on the Saint-Venant model,it allowed us to visualize the variation of the speed according to the thickness of the substance(from 0 to h)and to deduce the average speed of the substance on an inclined ***,this restrictive model does not take into account the effect of particle friction on the flow and considers that the thickness h is *** make our simulation more realistic,we opted for the Savage-hatter *** took into account the variation of the thickness on the particles speed,in addition we have studied the effect of the variation of many parameters on the granular flow,namely the temperature and the roughness of the substrate,the density and the compactness of the substance,we found that the speed of the particles increases and the treatment time decreases with an increase in temperature.

关键词： Granular flow friction cohesion angle ofinclination temperature

Partition of Unity Finite Element Analysis of Nonlinear Transient Diffusion Problems Using p-Version Refinement

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Computer Modeling in Engineering & Sciences 2020年第7期124卷 61-78页

作者： Abdelkarim El Kahoui Mustapha Malek Nouh Izem MShadi Mohamed mohammed Seaid Laboratory of Engineering Sciences Faculty of ScienceIbn Zohr UniversityAgadirMorocco School of Energy GeoscienceInfrastructure and SocietyHeriot-Watt UniversityEdinburghEH144ASUK Department of Engineering Durham UniversityDurhamDH13LEUK International Water Research Institute University Mohammed VI PolytechnicBenguerirMorocco

We propose a high-order enriched partition of unity finite element method for linear and nonlinear time-dependent diffusion *** solution of this class of problems often exhibits non-smooth features such as steep gradients and boundary layers which can be very challenging to recover using the conventional low-order finite element methods.A class of steady-state exponential functions has been widely used for enrichment and its performance to numerically solve these challenges has been ***,these enrichment functions have been used only in context of the standard h-version refinement or the so-called q-version *** this paper we demonstrate that the p-version refinement can also be a very attractive option in terms of the efficiency and the accuracy in the enriched partition of unity finite element ***,the transient diffusion problem is integrated in time using a semi-implicit scheme and the semi-discrete problem is then integrated in space using the p-version enriched finite *** results are presented for three test examples of timedependent diffusion problems in both homogeneous and heterogeneous *** computed results show the significant improvement when using the p-version refined enriched approximations in the finite element *** addition,these results support our expectations for a robust and high-order accurate enriched partition of unity finite element method.

关键词： Partition of unity finite element method p-version refinement

Spectral Evolution of hercules X-1 over Main high State from RXTE/PCA Observations

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Journal of high Energy Physics, Gravitation and Cosmology 2022年第4期8卷 896-918页

作者： Denis A. Leahy mohammed h. Abdallah Department of Physics and Astronomy University of Calgary Calgary Canada Astronomy Department National Research Institute of Astronomy and Geophysics (NRIAG) Cairo Egypt

We test different X-ray spectrum models to find the one that best represents the observed Rossi X-ray Timing Explore/Proportional Counter Array (RXTE /PCA) spectra of her X-1 during Main high state (Mh). We then apply this model to Mh observations taken over the lifetime of RXTE. From the results, we obtain patterns in the spectral parameters vs. 35-day phase during Mh. The precessing-disc occultation model explains the 35-day cycle by changes in observer view of the emission regions by the accretion disc 35-day precession. Qualitatively, we find that this model can describe the main spectral changes. however, several spectral parameters show detailed changes that the models have not addressed yet. These changes will likely require modifications to the basic precessing-disc model for the 35-day cycle.

关键词： X-Ray Binaries hercules X-1 X-Ray Spectrum

Prevalence of Cutaneous Disorders in Patients with Polycystic Ovary Syndrome

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Open Journal of Obstetrics and Gynecology 2020年第9期10卷 1246-1264页

作者： mohammed h. Mostafa Nader F. Ragab Ghada F. mohammed Department of Obstetrics and Gynecology Faculty of Medicine Ain Shams University Cairo Egypt Department of Dermatology Venereology and Andrology Faculty of medicine Ain Shams University Cairo Egypt

Purpose: To determine the prevalence of cutaneous disorders of PCOS and indicate the specific cutaneous lesions that have reliable association with PCOS. Methods: 134 female participants had met the criteria to be diagnosed as PCOS. Dermatological examination regarding hirsutism, acne, androgenic alopecia and acanthosis nigricans as well as any other cutaneous manifestations and assessment of each as regards duration, distribution and scoring was done. Hormonal assay for FSH/LH was done together with ultrasound examination. Results: The study included 134 female participants who had met the criteria to be diagnosed as PCOS; the range of age was 18 - 35 years, with a mean (26.31 ± 4.47 years). Among the PCOS patients at least one cutaneous disorder was found in 18 patients (13.4%), two cutaneous disorders in 44 patients (32.8%), three cutaneous disorders in 47 patients (35.1%), four cutaneous disorders in 24 (17.9%) and five cutaneous disorders were found in only one patient (0.7%). Statistically, there was a significant positive correlations between hirsutism, acne, acanthosis nigricans and Lh/F.S.h ratio (p here was non

关键词： hirsutism Acanthosis Negricans Acne Seborrheic Dermatitis

Software Effort Prediction Using Ensemble Learning Methods

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Journal of Software Engineering and Applications 2020年第7期13卷 143-160页

作者： Omar h. Alhazmi mohammed Zubair Khan Department of Computer Science College of Computer Science and Engineering Taibah University Madinah KSA

Software Cost Estimation (SCE) is an essential requirement in producing software these days. Genuine accurate estimation requires cost-and-efforts factors in delivering software by utilizing algorithmic or Ensemble Learning Methods (ELMs). Effort is estimated in terms of individual months and length. Overestimation as well as underestimation of efforts can adversely affect software development. Hence, it is the responsibility of software development managers to estimate the cost using the best possible techniques. The predominant cost for any product is the expense of figuring effort. Subsequently, effort estimation is exceptionally pivotal and there is a constant need to improve its accuracy. Fortunately, several efforts estimation models are available;however, it is difficult to determine which model is more accurate on what dataset. Hence, we use ensemble learning bagging with base learner Linear regression, SMOReg, MLP, random forest, REPTree, and M5Rule. We also implemented the feature selection algorithm to examine the effect of feature selection algorithm BestFit and Genetic Algorithm. The dataset is based on 499 projects known as China. The results show that the Mean Magnitude Relative error of Bagging M5 rule with Genetic Algorithm as Feature Selection is 10%, which makes it better than other algorithms.

关键词： Software Cost Estimation (SCE) Ensemble Learning Bagging Linear Regression SMOReg REPTree M5 Rule

Passively harmonic mode-locked erbium-doped fiber laser at a 580 Mhz repetition rate based on carbon nanotubes film

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Chinese Optics Letters 2018年第2期16卷 117-121页

作者： Qianqian huang Tianxing Wang Chuanhang Zou mohammed AIAraimi Aleksey Rozhin Chengbo Mou Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai UniversityShanghai 200072China Aston Institute of Photonic Technologies(AIPT) Aston UniversityBirminghamB47ETUnited Kingdom Nanoscience Research Croup Aston UniversityBirmingham B47ETUnited Kingdom Al Musanna College of Technology MuladdahA1 Musanna P.C.314Sultanate of Oman

We propose and demonstrate a passively harmonic mode-locked erbium-doped fiber laser(EDFL)using carbon nanotubes polyvinyl alcohol(CNTs-PVA)*** laser allows generation of the pulses with a repetition rate of 580 Mhz,which corresponds to the 22nd harmonics of a 26.3 Mhz fundamental repetition rate under 323 mW pump power.A particularly noteworthy feature of the pulses is the super-mode suppression ratio(SMSR),which is over 40 dB,indicating a stable operation.

关键词： Carbon nanotubes Erbium fibers Fiber devices Fiber lasers Optical networks Semiconductor saturable absorber mirrors

Post-cholecystectomy iatrogenic bile duct injuries:Emerging role for endoscopic management

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World Journal of Gastrointestinal Surgery 2023年第12期15卷 2709-2718页

作者： Mohamed h Emara mohammed hussien Ahmed Mohamed I Radwan Emad hassan Emara Magdy Basheer Ahmed Ali Asem Ahmed Elfert Department of hepatology Gastroenterology and Infectious DiseasesKafrelsheikh UniversityKafr-Elshikh 33516Egypt Department of Tropical Medicine Zagazig UniversityZagazig 44519Egypt Department of Diagnostic and Interventional Radiology Kafrelsheikh UniversityKafr-Elshikh 33516Egypt Department of Surgery Mansoura UniversityMansours 44176Egypt Department of Emergency Hargeisa Group HospitalHargeisa 1235Somalia Department of Tropical Medicine Tanta UniversityTanta 33120Egypt

Post-cholecystectomy iatrogenic bile duct injuries(IBDIs),are not uncommon and although the frequency of IBDIs vary across the literature,the rates following the procedure of laparoscopic cholecystectomy are much higher than open *** injuries caries a great burden on the patients,physicians and the health care systems and sometime are *** are associated with different manifestations that are not limited to abdominal pain,bile leaks from the surgical drains,peritonitis with fever and sometimes *** injuries if not witnessed during the surgery,can be diagnosed by combining clinical manifestations,biochemical tests and imaging *** such techniques abdominal US is usually the first choice while Magnetic Resonance Cholangio-Pancreatography seems the most *** approach was the ideal approach for such cases,however the introduction of Endoscopic Retrograde Cholangio-Pancreatography(ERCP)was a paradigm shift in the management of such injuries due to accepted success rates,lower cost and lower rates of associated morbidity and ***,the literature lacks consensus for the optimal timing of ERCP intervention in the management of *** management of IBDIs can be tailored according to the nature of the underlying *** the subgroup of patients with complete bile duct ligation and lost ductal continuity,transfer to surgery is indicated without *** patients will not benefit from endoscopy and hence should not do unnecessary *** low–flow leaks *** bed leaks,conservative management for 1-2 wk prior to ERCP is advised,in contrary to high-flow leaks *** duct leaks and stricture lesions in whom early ERCP is *** plus stenting is the ideal management line for cases of *** radiologic techniques are promising options especially for cases of failed endoscopic repair and also for cases with altered *** studies will

关键词： Iatrogenic bile duct injuries Cholecystectomy Surgical repair Endoscopic Retrograde Cholangio-Pancreatography Interventional radiology

Consensus statement on the epidemiology,diagnosis,prevention,and management of cow's milk protein allergy in the Middle East:a modified Delphi-based study

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World Journal of Pediatrics 2021年第6期17卷 576-589页

作者： Moustafa A.El-hodhod Mortada h.F.El-Shabrawi Ahmed AIBadi Ahmed hussein AM Almehaidib Basil Nasrallah Ebtsam mohammed AIBassam hala El Feghali hasan M.Isa Khaled Al Saraf Maroun Sokhn Mehdi Adeli Najwa mohammed Mousa Al-Sawi Pierre hage Suleiman Al-hammadi Department of Pediatrics Faculty of MedicineAin Shams UniversityCairoEgypt Faculty of Medicine October 6 UniversityGizaEgypt Faculty of Medicine Cairo UniversityCairoEgypt International Pediatric Association(IPA) MarengoUSA International Society of Tropical Pediatrics(ISTP) ManilaPhilippines DRC hospital MuscatOman Al Amiri and Al Adan hospitals KuwaitKuwait Pediatric Gastroenterology Department of PediatricsKing Faisal Specialist Hospital and Research Center RiyadhRiyadhSaudi Arabia American hospital Dubai DubaiUnited Arab Emirates Nutrition Service Department King Faisal Specialist and Research Center RiyadhRiyadhSaudi Arabia ChU Notre Dame de Secours ByblosLebanon Pediatric Department Salmaniya Medical ComplexManamaBahrain Pediatric department Arabian Gulf UniversityManamaBahrain Pediatrics Department Dar Al Shifa HospitalKuwaitKuwait Pediatric Gastroenterology Hepatologyand Nutrition DepartmentSaint George University Medical CenterUniversity of BalamandBeirutLebanon Sidra Medicine DohaQatar Department of Pediatrics Doctor Sulaiman Alhabib Medical GroupAlrryan BranchRiyadhSaudi Arabia Pediatric Pulmonology and Allergology University of BalamandBeirutLebanon College of Medicine Mohanuned Bin Rashid University of Medicine and Health SciencesBuilding 14505055 DubaiUnited Arab Emirates

Background This study aimed to develop an expert consensus regarding the epidemiology,diagnosis,and management of cow’s milk protein allergy(CMPA)in the Middle *** A three-step modified Delphi method was utilized to develop the *** specialized pediatricians participated in the development of this *** statement was considered a consensus if it achieved an agreement level of>80%.Results The experts agreed that the double-blind placebo-controlled oral challenge test(OCT)should be performed for 2-A weeks using an amino acid formula(AAF)in formula-fed infants or children with suspected ***-fed infants with confirmed CMPA should be offered a therapeutic *** panel stated that an extensively hydrolyzed formula(ehF)is indicated in the absence of red flag *** the same time,the AAF is offered for infants with red flag signs,such as severe anaphylactic *** panel agreed that infants on an ehF with resolved symptoms within 2-4 weeks should continue the ehF with particular attention to the growth and nutritional *** the other hand,an AAF should be considered for infants with persistent symptoms;the AAF should be continued if the symptoms resolve within 2-4 weeks,with particular attention to the growth and nutritional *** cases with no symptomatic improvements after the introduction of an *** measures should be *** panel developed a management algorithm,which achieved an agreement level of 90.9%.Conclusion This consensus document combined the best available evidence and clinical experience to optimize the management of CMPA in the Middle East.

关键词： Consensus Cow's milk protein allergy Infant formula Middle East Milk hypersensitivity