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Fabrication and characterization of gold nano particles for DNA biosensor applications

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Chinese Chemical Letters 2016年第5期27卷 801-806页

作者： ahmed Mishaal mohammed Chemistry Department College of Science Anbar University institutes of Nano Electronic Engineering University Malaysia Perlis

This research involves the preparation ofa biosensor using silicon oxide for biomedical applications, and its effective use for the detection of target DNA hybridization. An electrochemical DNA biosensor was successfully fabricated by using （3-aminopropyl） tri-ethoxysilane （APTES） as a linker molecule combined with gold nanoparticles （GNPs） on a thermally oxidized 5i02 thin film. The size of the GNPs was calculated by utilizing UV-vis data with an average calculated particle size within the range of 30 - 5 nm, and characterization by transmission electron microscopy （TEM） and atomic force microscopy （AFM）. The GNP-modified SiO2 thin films were electrically characterized through the measurement of capacitance, permittivity and conductivity using a low-cost dielectric analyzer. The capacitance, permittivity and conductivity profiles of the fabricated sensor clearly differentiated DNA immobilization and hybridization.

关键词： Gold nanoparticlesElectrochemical DNA hybridization Dielectric analyzer

Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： ahmed M.ATTA Reda N.BEHiRY mohammed i.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt Nile Higher institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

Energy Efficiency of a Solar Green Building Using Bio-Sourced Materials for indoor Temperature and Humidity Optimization

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Energy Engineering 2025年第1期122卷 41-62页

作者： SoumiaMounir Youssef Maaloufa Abdelhamid Khabbazi ElinaMohd Husini Nurul SyalaAbdul Latip YakubuAminuDodo Rime ELHarrouni MinaAmazal Asma Souidi Malika Atigui.ahmed Aharoune National School of Architecture Agadir New Complex Ibn ZohrAgadirBP 20732Morocco EMDD CERNE2DUniversity of Mohammed V in RabatEst SaleSaleBP 227Morocco Thermodynamics and Energetics Laboratory Faculty of ScienceIbn Zohr UniversityAgadirBP 8106Morocco Faculty of Built Environment University Sains Islam MalaysiaNilaiBP 71800Malaysia Architectural Engineering Department Najran UniversityNajranBP 1988Saudi Arabia The Centre of Scientific and Engineering Research Najran UniversityNajranBP 1988Saudi Arabia Euro-Mediterranean School of Architecture Design and UrbanismEuro-Mediterranean University of FezFezBP 51Morocco

A clean environment with low carbon emissions is the goal of research on the development of green and sustainable buildings that use bio-sourced materials in conjunction with solar energy to create more sustainable *** is particularly true in Africa,where there aren’t many studies on the *** current study suggests a 90 m^(2) model of a sustainable building in a dry climate that is movable to address the issue of housing in remote areas,ensures comfort in harsh weather conditions,uses solar renewable resources—which are plentiful in Africa—uses biosourced materials,and examines how these materials relate to temperature and humidity control while emitting minimal carbon *** order to solve the topic under consideration,the work is split into two sections:numerical and experimental *** TRNSYS and Revit,the suggested prototype building is examined numerically to examine the impact of orientation,envelope composition made of bio-sourced materials,and carbon *** a hygrothermal investigation,experiments are conducted to evaluate this prototype’s ***,an examination of the photovoltaic system’s production,consumption,and several scenarios used tomaximize battery life is included in the *** the biosourcedmaterial achieves a thermal transmittance of 0.15(W.m^(-2).K^(-1)),the results demonstrate an intriguing finding in terms of *** value satisfies the requirements of passive building,energy autonomy of the dwelling,and injection in-network with an annual value of 15,757 ***,compared to the literature,the heating needs ratio is 6.38(kWh/m^(2).an)and the cooling needs ratio is 49(kWh/m^(2).an),both of which are good *** to international norms,the inside temperature doesn’t go above 26℃,and the humidity level is within a comfortable range.

关键词： Bio-sourced materials energy sustainability green architecture built environment

investigation on the mechanical properties of sintered porous copper compacts

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China Particuology 2007年第6期5卷 391-394页

作者： Yasser M.Z. ahmed Mohamed i. Riad ahmed i. Zaky mohammed Abdel-Aziz Mohamed M.H. Shalabi Central Metallurgical Research and Development institute CMRDI El-Felzat Street El-Tabbin P.O. Box 87 Helwan Cairo Egypt

in line with recent attention on porous metals having low and medium porosities in the range of 20-50%, this paper studies the effect of porosity on the mechanical properties of sintered copper compacts. Experiments were designed to investigate the effect of porosity, applied stress and sliding velocity on the wear rate of copper compacts, leading to the finding that the effects of both porosity and applied stress of the wear test on the wear rate are approximately similar and higher than that of sliding velocity. The investigation concerning the effect of porosity on compressive strength indicated that the stress-strain curve of high-porosity compact exhibited identifiable ultimate strength points, though low-porosity compact showed distinct stages of elastic plastic behavior.

关键词： Porous copper Wear rate Compressive strength Experimental design technique

Robust Multi-Output Machine Learning Regression for Seismic Hazard Model Using Peak Crust Acceleration Case Study,Turkey,iraq and iran

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Journal of Earth Science 2023年第5期34卷 1447-1464页

作者： Shaheen mohammed Saleh ahmed Hakan Guneyli Department of Geology College of ScienceKirkuk UniversityKirkuk 36001Iraq Department of Geology Faculty EngineeringCukurova UniversityBalcali-Adana 01330Turkey

This paper for the first time improved a Robust Multi-Output machine learning regression model for seismic hazard zoning of Turkey, iraq and iran using constructed 3-D shear-wave velocity(Vs), seismic tomography dataset model for the crust and uppermost mantle beneath the study area. The focus of this paper’s opportunity is to develop a scientific framework leveraging machine learning that will ultimately provide the rapid and more complete characterization of earthquake properties. This work can be targeted at improving the seismic hazard zones system ability to detect and associate seismic signals, or at estimating other seismic characteristics(crust acceleration and crust energy) while traditionally, methods cannot monitor the earthquakes system. This work has derived some physical equations for extraction of many variables as inputs for our developed machine learning model based on a reliable understanding of the tomography data to physical variables by preparing huge dataset from different physical conditions of crust. We have extracted the velocity values of the shear waves from the original NETCDF file, which contains the S velocity values for every one km of the depths of the crust for the study area from one km down to the uppermost mantle beneath the Middle East. For the first time, this study calculated new seismic hazard parameter called Peak Crust Acceleration(PCA) for seismic hazard analysis by considering the transmitted initial seismic energy through the Earthy wrote in python language ’s crust layers from hypocenter. All machine learning algorithms in this studusing anaconda platform the open-source individual Edition(Distribution).

关键词： robust multi-output regressor tomography peak crust acceleration NETCDF machine learning hazards

Ding w-Flat Modules and Dimensions

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Algebra Colloquium 2018年第2期25卷 203-216页

作者： Fuad Ali.ahmed Almahdi mohammed Tamekkante Department of Mathematics Faculty of Sciences King Khalid University P. O. Box. 9004 Abha Saudi Arabia Laboratory MACS Faculty of Sciences University Moulay Ismail 5000 P.B. 11201 Zitoune Meknes Morocco

The introduction of w-operation in the class of flat modules has been successful. Let R be a ring. An R-module M is called a w-fiat module if Tor1r（M, N） is GV-torsion for all R-modules N. in this paper, we introduce the w-operation in Gorenstein homological algebra. An R-module M is called Ding w-flat if there exists an exact sequence of projective R-modules ... → P1 → P0 → p0 → p1 → ... such that M im（P0 → p0） and such that the functor HomR （-,F） leaves the sequence exact whenever F is w-flat. Several well- known classes of rings are characterized in terms of Ding w-flat modules. Some examples are given to show that Ding w-flat modules lie strictly between projective modules and Gorenstein projective modules. The Ding w-flat dimension （of modules and rings） and the existence of Ding w-flat precovers are also studied.

关键词： w-fiat module and dimension Gorenstein projective module and dimension,strongly Gorenstein flat module

A novel algorithm for distance measurement using stereo camera

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CAAi Transactions on intelligence Technology 2022年第2期7卷 177-186页

作者： Elmehdi Adil mohammed Mikou ahmed Mouhsen MiSi Laboratory Faculty of Sciences and TechniquesHassan First University of SettatSettatMorocco iMii Laboratory Faculty of Sciences and TechniquesHassan First University of SettatSettatMorocco

Distance estimation can be achieved by using active sensors or with the help of passive sensors such as *** stereo vision system is generally composed of two cameras to mimic the human binocular *** this paper,a Python-based algorithm is pro-posed to find the parameters of each camera,rectify the images,create the disparity maps and finally use these maps for distance *** using real-time im-ages,which were captured from our stereo vision system,of different obstacles posi-tioned at multiple distances(60-200 cm)prove the effectiveness of the proposed program and show that the calculated distance to the obstacle is relatively *** accuracy of distance measurement is up to 99.83%.The processing time needed to calculate the distance between the obstacle and the cameras is less than 0.355 s.

关键词： computer vision disparity maps distance measurement Python stereoscopic processing

Mathematical models for process commonality under quality and resources breakdown in multistage production

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第11期12卷 837-848页

作者： mohammed Abdul WAZED Shamsuddin ahmed Yusoff Bin NUKMAN Department of Engineering Design and Manufacture University of Malaya Department of Mechanical Engineering Chittagong University of Engineering and Technology(CUET)

it is essential to manage customers' diverse desires and to keep manufacturing costs as low as possible for survival in competition and eventually in *** resources in manufacturing for different products is a vital method of accomplishing this *** advantages of using a common process in production are stated in the ***,the mathematical models as well as simulation or conceptual models are not *** main objective of this paper is to develop mathematical models for multiproduct and multistage production under quality and breakdown *** idea of the process commonality is incorporated in the proposed *** models are validated by primary data collected from a Malaysian company and comparison of the timely requirement schedules of earlier MRP ii and the proposed models under stable and perfect production *** appreciable convergence of the outcomes is ***,the proposed models are carrying additional information about the available locations of the parts in a time *** validation,the effects of process commonality on cost,capacity and the requirement schedule under uncertainties are *** is observed that the use of common processes in manufacturing is always better than the non-commonality scenario in terms of production ***,the increase in capacity requirement for commonality designs is higher for an ideal system,while it is less when the system suffers from breakdowns and a quality problem.

关键词： Process commonality Mathematical model MRP ii Quality Breakdown

Types of trematodes infecting freshwater snails found in irrigation canals in the East Nile locality,Khartoum,Sudan

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infectious Diseases of Poverty 2016年第1期5卷 139-148页

作者： Nidal A.i.mohammed Henry Madsen Abdel Aziz A.R.M.ahmed Department of Zoology Khartoum College of Medical SciencesKhartoumSudan Parasitology and Aquatic Diseases Department of Veterinary Disease BiologyFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksbergDenmark Education Expert Company RiyadhKingdom of Saudi Arabia

Background:The planorbid freshwater snails of the two genera,Biomphalaria and Bulinus-have been vigorously studied due to the role they play as intermediate hosts of *** Sudan specifically,most studies have focused on the chemical and ecological control of the two genera,but few studies have looked at their biological *** study explored the coexistence of other species of freshwater snails and the two genera along with their trematode infections in relation to a number of environmental factors in the East Nile locality,Khartoum state,***:Freshwater snails from irrigation canals(abueshreens)were sampled monthly from January 2004 to December *** snails were examined for trematode infections by cercarial emergence immediately after collection and then weekly for an additional four weeks to allow for the maturation of prepatent *** cover in the study sites as well as the physicochemical characteristics of the water,including temperature,were also ***:A total of 10,493 snails,representing seven species,were *** most abundant species was Biomphalaria pfeifferi,representing 48.6%of the ***,14.1%of the snails were found to be shedding some type of *** species were found to have infections;among these the Bulinus truncatus species was found to be the most heavily infected,with an overall prevalence of 46.2%.Double infections were recorded in only two *** snails and one Cleopatra bulimoides *** different morphotypes of cercariae were recorded,seven of which appeared not to conform to previously described cercariae from *** type 1 was the most common type of cercariae recovered,accounting for 44.3% of all *** density of snails tended to be lower during the summer months than the winter months,except for *** snails,which were not affected by seasonal ***:The findings of this study indicate that besides sc

关键词： Freshwater snails Trematode cercariae Biomphalaria Bulinus East Nile locality Khartoum Sudan