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Frontiers of Structural and Civil Engineering 2022年第8期16卷 976-989页

作者： Abdelwahhab KHATIR Roberto CAPOZUCCA samir KHATIR Erica MAGAGNINI Structural Section DICEA Polytechnic University of MarcheAncona 60131Italy Faculty of Civil Engineering Ho Chi Minh City Open UniversityHo Chi Minh City 700000Vietnam

Vibration-based damage detection methods have become widely used because of their advantages over traditional *** paper presents a new approach to identify the crack depth in steel beam structures based on vibration analysis using the Finite Element Method(FEM)and Artificial Neural Network(ANN)combined with Butterfly Optimization Algorithm(BOA).ANN is quite successful in such identification issues,but it has some limitations,such as reduction of error after system training is complete,which means the output does not provide optimal *** paper improves ANN training after introducing BOA as a hybrid model(BOA-ANN).Natural frequencies are used as input parameters and crack depth as *** data are collected from improved FEM using simulation tools(ABAQUS)based on different crack depths and locations as the first ***,data are collected from experimental analysis of cracked beams based on different crack depths and locations to test the reliability of the presented *** proposed approach,compared to other methods,can predict crack depth with improved accuracy.

关键词： damage prediction ANN BOA FEM experimental modal analysis

Global asymptotic stability for a SEI reaction-diffusion model of infectious diseases with immigration

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International Journal of Biomathematics 2018年第3期11卷 289-305页

作者： Salem Abdelmalek samir Bendoukha Department of Mathematics University of Tebessa 12002 Algeria Department of Electrical Engineering College of Engineering Yanbu Taibah University Saudi Arabia

This paper studies the local and global stability of solutions for a spatially spread SEI epidemic model with immigration of individuals using a Lyapunov functional. It is shown that in the presence of diffusion, the unique steady state remains globally stable. Numerical results obtained through Matlab simulations are presented to confirm the findings of this study.

关键词： SEI epidemic model reaction-diffusion global asymptotic stability Lyapunov functional.

Topical tacrolimus in anterior segment inflammatory disorders

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Eye and Vision 2017年第1期4卷 30-36页

作者： samir S.Shoughy The Eye Center and the Eye Foundation for Research in Ophthalmology PO Box 55307Riyadh 11534Saudi Arabia

Immune mediated inflammatory anterior segment diseases are variable and their management requires intense *** with topical steroids is associated with serious ocular side *** order to overcome the potentially blinding complications of topical steroids,immunomodulatory drugs are being used more *** is a calcineurin inhibitor that induces suppression of T lymphocytes activity and reduction of ocular *** was recently investigated for application in various anterior segment inflammatory *** this review,we will discuss the therapeutic application of topical tacrolimus as a steroid-sparing agent in treating T cell mediated anterior segment inflammation.

关键词： Tacrolimus Topical Ocular Immune-mediated T cells

Recommending the IHACRES model for water resources assessment and resolving water conflicts in Africa

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Journal of Arid Land 2011年第1期3卷 40-48页

作者： samir Mohammad Ali Alredaisy Department of Geography Faculty of EducationUniversity of Khartoum

The International Association of Hydrological Sciences （IAHS） recognized the lack of hydro- logical data as a world-wide problem in 2002 and adopted the Prediction of Ungauged Basins （PUB） as a decadal research agenda during the period of 2003 to 2012. One of the objectives is to further develop methodologies for prediction in ungauged basins and to reduce uncertainties in model prediction. Estimation of stream flows is required for flood control, water quality control, valley habitat assessment and water budget of a country. However, the majority of water catchments, streams and valleys are ungauged in most developing countries. The main objective of this paper is to introduce the IHACRES （Identification of Hy- drographs and Components from Rainfall, Evaporation and Stream） model into African hydrological plan- ning as a methodology for water resources assessment, which in turn can be used to resolve water conflicts between communities and countries and to study the climate change issues. This is because the IHACRES model is applied for the estimation of flows in ungauged catchments whose physical catchments descriptors （PCDs） can be determined by driving variables （i.e. rainfall and temperature）; and also in gauged streams but whose gauging stations are no longer operational but historical data are available for model calibration. The model provides a valuable insight into the hydrologic behaviour of the upper water sources for valleys as well as provides a useful methodology for water resources assessment in situations of scarce financial resources in developing countries. In addition, it requires relatively few parameters in its calibration and has been successful applied in previous regionalization studies. It will also make possible the equitable distri- bution of water resources in international basins and rivers＇ catchments. This paper does not apply the model anywhere, but recommends it as a methodology for water resources assessment in order to cure water

关键词： ungauged catchment water resources assessment rainfall runoff lumped models Nile Basin Africa

Mitigating the catastrophic impacts of torrential rivers in semi-arid environments: a case of the Gash River in eastern Sudan

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Journal of Arid Land 2011年第3期3卷 174-183页

作者： samir Mohammad Ali Alredaisy Department of Geography Faculty of EducationUniversity of Khartoum

The climatic, geomorphic, hydrologic and aquifer characteristics of the torrential Gash River across mountainous areas, in far eastern Sudan, were analyzed in order to mitigate its recurring catastrophic impacts. Hydrologic and climatic data and interpretation of Gash River satellite images were from relevant research works carried out in Gash Basin from 1985 to 2008. The results indicated that the total catchment area of Gash River is about 21,000 km2, and the basin area is 31,000 km2. The total length of Gash River is 450 km and the average slope is 200 cm/km. The width of the catchment varies from 30 m to 90 m and that of the basin is from 100 m to 800 m, and the course of the river is varied. During the period of 1980？2008, the mean annual rainfall was 250 mm and the mean annual discharge was 6.8 ×10~8 m^3, and the flooding is approximately one time per 5 years. Torrential floods measured at Kassala town since 1907 showed that an absolute maximum discharge was 876 m3/s and a mean maximum discharge was 365 m3/s. These characteristics differ widely between catchment and basin areas. The author proposes that, by analyzing the climatic, geomorphic, hydrologic and aquifer characteristics of the Gash River and considering the role of community, a concise database could be provided to formulate the aquifer, geomorphic, hydrologic and climatic （AQUIGEOHYCLIM） regional approach to mitigate Gash River recurring catastrophic impacts.

关键词： AQUIGEOHYCLIM Gash River basin climate geomorphology hydrology mitigation water management

Prognostic Role of Preoperative Tricuspid Annular Plane Systolic Excursion (TAPSE) in Mitral Valve Replacement (MVR) for Rheumatic Mitral Stenosis Patients

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World Journal of Cardiovascular Surgery 2024年第8期14卷 115-130页

作者： Satyajit Sharma Muhit Abdullah Md. Noor-E-Elahi Mozumder Munjerin Refat Synthee Md. Zafar-Al-Nimari Anowarul Azim Saikat Das Gupta Dewan Iftakher Raza Chowdhury Siddhartha Shankar Howlader Noel Crypian Gomes Saleh Ahmed samir Kumar Biswas Department of Cardiac Surgery National Heart Foundation Hospital & Research Institute (NHFH & RI) Dhaka Bangladesh Department of Cardiac Surgery National Institute of Cardiovascular Diseases & Hospital Dhaka Bangladesh Department of Cardiothoracic and Vascular Surgery Square Hospital Dhaka Bangladesh Department of Cardiothoracic and Vascular Surgery Evercare Hospital Chattogram Bangladesh

Tricuspid annular plane systolic excursion has been proposed as a simple and reproducible parameter for quantitative assessment of the right ventricular ejection fraction. The prognostic importance of preoperative TAPSE in patients with mitral valve replacement for rheumatic mitral stenosis patients is still under focused. Therefore, the objective of the study was to predict the outcome after MVR in rheumatic mitral stenosis patients in relation to preoperative TAPSE. This comparative cross-sectional study was conducted at the Department of Cardiac Surgery, National Heart Foundation Hospital and Research Institute. A total of 72 patients of rheumatic mitral stenosis patients who underwent mitral valve replacement were included in the study. They were divided into two groups: Group A and B. Group A included 36 patients with TAPSE 0.05) except for the preoperative TAPSE. Mean TAPSE of Group A was 13.17 (±1.40) and Group B was 18.61 (±1.57), the difference was statistically significant (p 0.05). Among the postoperative complications, including postoperative atrial fibrillation was higher in Group A (30.56%) than Group B (11.11%), mean ventilation time was higher in Group A (27.78%) than Group B (5.56%), length of intensive care was higher in Group A (33.33%) than Group B (11.12%), and hospital stay was higher in Group A (25.0%) than Group B (5.56%), (p < 0.05). Higher preoperative TASPE could be used as a prognostic tool for MVR in rheumatic mitral stenosis patients in our settings.

关键词： Tricuspid Annular Plane Systolic Excursion Mitral Valve Replacement Rheumatic Heart Disease Mitral Stenosis Right Ventricular Ejection Fraction Postoperative Complications

ON THE SUPERSTABILITY OF THE PEXIDER TYPE GENERALIZED TRIGONOMETRIC FUNCTIONAL EQUATIONS

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Acta Mathematica Scientia 2014年第6期34卷 1749-1760页

作者： Driss ZEGLAMI Ahmed CHARIFI samir KABBAJ Department of Mathematics E.N.S.A.M Moulay Ismail University Department of Mathematics Faculty of SciencesIbn Tofail University

The aim of this paper is to investigate the superstability problem for the pexiderized trigonometric functional equation∑ v∈Φ∫Kf（xkv（y）k^-1）dwK（k）= Φ g（x）h（y）, x, y ∈ G,where G is any topological group, K is a compact subgroup of G, ωK is the normalized Haar measure of K, Φ is a finite group of K-invariant morphisms of G and f, g, h are continuous complex-valued ***, we have generalized the results of stability for d＇Alembert＇s and Wilson＇s equations by R. Badora, J. Baker, B. Bouikhalene, P. Gavruta, S. Kabbaj, Pl. Kannappan, G. ***, J.M. Rassias, A. Roukbi, L. Sz′ekelyhidi, D. Zeglami, etc.

关键词： superstability generalized Pexider d'Alembert equation Wilson's functional equation group of morphisms

GLOBAL EXISTENCE AND ASYMPTOTIC BEHAVIOR OF SOLUTIONS FOR SOME COUPLED SYSTEMS VIA A LYAPUNOV FUNCTIONAL

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Acta Mathematica Scientia 2019年第6期39卷 1538-1550页

作者： Lamia DJEBARA Salem ABDELMALEK samir BENDOUKHA Department of Mathematics and Computer Science ICOSI LaboratoryUniversity of KhenchelaKhenchela04000Algeria Department of Mathematics and Informatics Faculty of Exact Sciences and Natural Sciences and LifeUniversity of Larbi TebessiTebessa12002Algeria Electrical Engineering Department College of Engineering at YanbuTaibah UniversitySaudi Arabia

The purpose of this work is to study the global existence and asymptotic behavior of solutions to a coupled reaction-diffusion system describing epidemiological or chemical situations. Our analytical proofs are based ... 详细信息

关键词： epidemic model reaction-diffusion global existence of solutions asymptotic stability

Spectral lags of flaring events in LS I+61°303 from RXTE Observations

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Research in Astronomy and Astrophysics 2016年第7期16卷 29-38页

作者： Tamal Sarkar samir Sarkar Arunava Bhadra High Energy&Cosmic Ray Research Centre University of North BengalSiliguriWB 734013India University Science Instrumentation Centre University of North BengalSiliguriWB 734013India

This work reports the first discovery of（negative） spectral lags in X-ray emission below 10 ke V from the gamma ray binary LS I＋61？303 during large flaring episodes using Rossi X-ray Timing Explorer（RXTE） observations. It is found from the RXTE data that during the flares, low energy（3–5 ke V） variations lead the higher energy（8–10 ke V） variations by a few tens of seconds whereas no significant time lag is observed during the non-flaring states. The observed spectral lag features for flaring events suggest that inverse Compton scattering may be operating, at least in some part of the system. Another possibility is that the sites of particle acceleration may be different for flaring and non-flaring events such as in the microquasar model, in which the flaring radiation may come from hot spots sitting above the black hole while steady state emissions are due to the jets.

关键词： X-rays:binaries X-rays:individual(LS I+61?303)

Shear reinforcement effect of reinforced concrete tie-columns on the lateral resistance of confined masonry walls

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Earthquake Engineering and Engineering Vibration 2016年第2期15卷 313-324页

作者： samir Bouhedja Abdelkrim Bourzam Ahmed Boukhaled Ammar Nechnech University of Sciences and Technology Houari Boumediene(USTHB)Faculty of Civil EngineeringLaboratory of EnvironmentWaterGeomechanics and Structures(LEEGO)BP 32 El AliaBab EzzouarAlgiers16111Algeria University of Sciences and Technology Houari Boumediene(USTHB)Faculty of Civil EngineeringLaboratory of Built Environment Research(LBE)BP 32 El AliaBab EzzouarAlgiers16111Algeria

Tie-columns improve significantly the lateral resistance of masonry bearing walls against persistent, transient and accidental loads. The research work described herein has been carried out to assess the lateral resistance of confined masonry walls, where contribution of the masonry panel is evaluated according to material mechanics and tie-columns effect is estimated by a proposed analytical formulation based on a model reported on previously. This approach takes into account the effect of dowel support on the reaction of its adjacent shear reinforcement： the conditions for the various contributions of transverse reinforcements are better defined following a clear evaluation of the participation ratio of these reinforcements. Lateral resistances of confined masonry walls measured in full-scale tests and gleaned from the literature are compared and checked with resistances calculated using the present approach.

关键词： reinforcement columns confined reinforced walls Shear formulation panel participation herein