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Frontiers of Structural and Civil Engineering 2023年第3期17卷 411-428页

作者： sayed ahmed Hossam ATEF Mohamed HUSAIN Department of Structural Engineering Faculty of EngineeringZagazig UniversityZagazig 44519Egypt Track Work Department National Authority for TunnelsCairo 11522Egypt

In this study,ultrahigh-performance fiber-reinforced concrete(UHPFRC)used in a type B70 concrete sleeper is investigated experimentally and *** main parameters investigated are the steel fiber volume fractions(0%,0.5%,1%,and 1.5%).Under European standards,35 UHPFRC sleepers are subjected to static bending tests at the center and rail seat sections,and the screw on the fastening system is pulled *** first cracking load,failure load,failure mode,crack propagation,load–deflection curve,load–crack width,and failure load from these tests are measured and compared with those of a control sleeper manufactured using normal concrete *** accuracy of the parametric study is verified ***,the results of the study are applied to UHPFRC sleepers with different concrete volumes to investigate the effects of the properties of UHPFRC on their *** and parametric study results show that the behavior of UHPFRC sleepers improves significantly when the amount of steel fiber in the mix is *** manufactured using UHPFRC with a steel fiber volume fraction of 1%and a concrete volume less than 25%that of standard sleeper B70 can be used under the same loads and requirements,which contributes positively to the cost and surrounding environment.

关键词： pre-stressed concrete sleeper ultrahigh performance fiber-reinforced concrete pull-out test static bending test steel fiber aspect ratio volume fraction

Assessment of clay stiffness and strength parameters using index properties

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 579-593页

作者： sayed M.ahmed Structural Engineering Department Ain Shams University

A new approach is developed to determine the shear wave velocity in saturated soft to firm clays using measurements of the liquid limit, plastic limit, and natural water content with depth. The shear wave velocity is assessed using the site-specific variation of the natural water content with the effective mean stress. Subsequently, an iterative process is envisaged to obtain the clay stiffness and strength *** at-rest earth pressure coefficient, as well as bearing capacity factor and rigidity index related to the cone penetration test, is also acquired from the analyses. Comparisons are presented between the measured clay parameters and the results of corresponding analyses in five different case studies. It is demonstrated that the presented approach can provide acceptable estimates of saturated clay stiffness and strength parameters. One of the main privileges of the presented methodology is the site-specific procedure developed based on the relationships between clay strength and stiffness parameters, rather than adopting direct correlations. Despite of the utilized iterative processes, the presented approach can be easily implemented using a simple spreadsheet, benefiting both geotechnical researchers and practitioners.

关键词： Soft to firm clays Atterberg limits Shear wave velocity Small-strain shear modulus Constrained modulus Undrained shear strength Effective friction angle Cone penetration test

Position Control of Synchronous Motor Drive by Modified Adaptive Two-phase Sliding Mode Controller

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International Journal of Automation and computing 2008年第4期5卷 406-412页

作者： Mohamed Said sayed ahmed Automation Science and Electrical Engineering School Beijing University of Aeronautics and Astronautics

A modified adaptive two-phase sliding mode controller for the synchronous motor drive that is highly robust to uncertain- ties and external disturbances is proposed in this *** proposed controller uses two-phase sliding mode control (SMC) where the 1st phase mainly controls the system in steady states and disturbed states-it is a smoothing *** 2nd phase is used mainly in the case of disturbed ***,it is an autotuning phase and uses a simple adaptive algorithm to tune the gain of conventional variable structure control (VSC).The modified controller is useful in position control of a permanent magnet synchronous drive.

关键词： Reaching law adaptive control sliding mode control (SMC) chattering.

Spatial-Temporal Water Balance Evaluation in The Nile Valley Upstream of The New Assiut Barrage，Egypt

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Spatial-Temporal Water Balance Evaluation in The Nile Valley...

作者： ahmed sayed Eladly Abdelhafiz 扬州大学

学位级别：硕士

Pyronaridine combined with diminazene aceturate inhibits Babesia in vitro and in vivo

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Asian Pacific Journal of Tropical Biomedicine 2024年第3期14卷 93-99页

作者： Shimaa Abd El-Salam El-sayed Mohamed Z.sayed-ahmed Shaimaa ahmed Awad Ali Nourah Alsadaan Nawazish Alam Mahmoud S.Alkhoudary Ikuo Igarashi Mohamed Abdo Rizk National Research Center for Protozoan Diseases Obihiro University of Agriculture and Veterinary MedicineInada-ChoObihiroHokkaido 080-8555Japan Department of Biochemistry and Chemistry of Nutrition Faculty of Veterinary MedicineMansoura UniversityMansoura 35516Egypt Department of Clinical Pharmacy College of PharmacyJazan UniversityJazan 45142Saudi Arabia Medical-Surgical Department College of NursingJouf UniversitySakaka 72388Saudi Arabia Critical Care and Emergency Nursing Faculty of NursingMansoura UniversityEgypt College of Nursing Jouf UniversitySakaka 72388Saudi Arabia Faculty of Pharmacy Mansoura UniversityMansoura 35516DakahliaEgypt Department of Internal Medicine and Infectious Diseases Faculty of Veterinary MedicineMansoura UniversityMansoura 35516Egypt

Objective:To evaluate the combination therapy of pyronaridine tetraphosphate and diminazene aceturate against Babesia in vitro and in ***:Bioinformatic analysis was performed using atom pair *** in vitro combination test was performed against Babesia bovis and Theileria ***,the in vivo chemotherapeutic efficacy of pyronaridine tetraphosphate in combination with diminazene aceturate was investigated against the growth of Babesia microti in mice using a fluorescence inhibitory ***:Pyronaridine tetraphosphate and diminazene aceturate exhibited nearly similar molecular *** in vitro combination of pyronaridine tetraphosphate and diminazene aceturate was synergistic on Babesia bovis and additive on Theileria *** addition,5 mg/kg pyronaridine tetraphosphate combined with 10 mg/kg diminazene aceturate inhibited Babesia microti growth significantly compared with those observed after treatment with 25 mg/kg diminazene aceturate alone from day 6 post treatment to day 12 post *** combination therapy also normalized the hematological parameters of infected ***:An oral dose of pyronaridine tetraphosphate combined with a subcutaneous dose of diminazene aceturate inhibits Babesia in vitro and in mice,suggesting it might be a new paradigm for the treatment of babesiosis.

关键词： Babesia Pyronaridine tetraphosphate Diminazene aceturate Babesiosis Theileria

Nag Mohashoy Temple Complex,Narayanganj:A Case Study of Adaptive Reuse for Hindu Religious Site

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Journal of World Architecture 2024年第5期8卷 1-17页

作者： sayed ahmed Department of Architecture Leading UniversitySylhetBangladesh

With an emphasis on the religious component of reuse potentiality,this study investigates the crucial nexus between spatial development and the conservation model for religious practice with socio-communal *** reuse is a critical tactic for global preservation and revitalization to elevate heritage sites in culturally significant locations but provides contemporary functions to them *** study examines the various facets of adaptive reuse concerning the religious cultural heritage of suppressed minorities,stressing its insight and importance including the inherent cultural worth of ancient structures and difficulties through creative solutions to modify the temple with modern *** research methodology approaches through an extensive analysis of the literature and case studies and ends with design *** looks into the socioeconomic advantages of adaptive reuse in religious practice,such as the promotion of pilgrimage tourism,community revitalization,and sustainable *** possible findings will emphasize the conversation on sustainable heritage management by combining theoretical frameworks with practical discoveries as an architectural project with certain concepts.

关键词： Cultural heritage Architectural conservation Sustainability Adaptive reuse Community participation

Bond-slip Behavior of BFRP Bars in Concrete under Cyclic Loading

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Bond-slip Behavior of BFRP Bars in Concrete under Cyclic Loa...

作者：雅德（Shehabeldeen ahmed sayed ahmed）东南大学

学位级别：硕士

本研究旨在探讨单调和循环荷载下BFRP筋的粘结性能。对4种不同表面处理(光圆、缠绕、包裹和裹砂)的BFRP筋在单调荷载下进行了一系列的标准拉拔试验,并与变形钢筋进行了比较。研究参数包括筋材直径、混凝土抗压强度和筋材表面处理方式。... 详细信息

本研究旨在探讨单调和循环荷载下BFRP筋的粘结性能。对4种不同表面处理(光圆、缠绕、包裹和裹砂)的BFRP筋在单调荷载下进行了一系列的标准拉拔试验,并与变形钢筋进行了比较。研究参数包括筋材直径、混凝土抗压强度和筋材表面处理方式。结果表明,表明处理对筋材在单调荷载下的粘结性能有显著的影响,表面缠绕的BFRP筋粘结性能相比其他方式更具有优越性。然后,为了研究BFRP筋在循环荷载下的粘结性能,进行了循环荷载拉拔试验。试验中采用了6种不同特征的循环加载模式,并以单调荷载结束以确定BFRP筋的残余粘结应力。研究了 BFRP筋表面处理方式、混凝土抗压强度、循环荷载加载卸载次数、循环荷载幅值、循环荷载方向(拉-拉和拉-压)对BFRP筋粘结性能的影响,并与变形钢筋进行了比较。所有试验筋材的粘结性能均出现了退化,退化幅度随着筋材表面处理方式以及加载条件的不同,幅度变化在轻微退化和严重退化之间。表面缠绕的BFRP筋粘结性能相比其他筋材受到循环荷载的影响更小。循环荷载的加载次数对粘结性能的影响相比其他荷载参数更大。基于试验结果,提出了一种数值模型来计算表面缠绕的BFRP筋循环荷载下的粘结性能,并与试验结果进行比较,对该模型的准确性和可靠性进行了评估。

关键词： bond BFRP cyclic concrete model surface

Influence of NaCI and Na2SO4 Treatments on Growth Development of Broad Bean （Vicia Faba, L.） Plant

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Journal of Life Sciences 2011年第7期5卷 513-523页

作者： Hameda El sayed ahmed El sayed Department of Biology Faculty of Applied Science for Girls Umm Al Qura University Makkah AI Mukaramah Jeddah 3111-23526Kingdom of Saudi Arabia

Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both salts whereas uptake of Ca^2＋ retarded mainly by Na2SO4. Chlorophyll content was affected mainly by NaCl, while Na2SO4 treatment lowered the rate of photosynthetic activity. Both salt compounds caused accumulation of free amino acids including free proline but reduced the protein content in the leaves. The salt tolerance capacity of the broad beans plant in which the observations of the effect of salinity determined by different concentrations of NaCI and Na2SO4 on growth, chloroplast pigments, photosynthetic, free amino acids, free proline, protein and inorganic elements on plants are combined with observations on growth and yield, in order to arrive at a better understanding of their salt tolerance, has been studied and discussed in this paper. The results for the latter only （fruiting stage） are presented.

关键词： Broad bean Viciafaba L. salinity growth photosynthetic activity elements amino acids proline protein.

Early detection of hepatocellular carcinoma co-occurring with hepatitis C virus infection: A mathematical model

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World Journal of Gastroenterology 2016年第16期22卷 4168-4182页

作者： Abdel-Rahman Nabawy Zekri Amira Salah El-Din Youssef Yasser Mabrouk Bakr Reham Mohamed Gabr Ola sayed ahmed Mostafa Hamed Elberry ahmed Mahmoud Mayla Mohamed Abouelhoda Abeer A Bahnassy Molecular Virology and Immunology Unit Cancer Biology Department National Cancer Institute Cairo University Systems and Biomedical Engineering Department Faculty of Engineering Cairo University Center for Informatics Sciences Nile University Sheikh Zayed City Pathology Department National Cancer Institute Cairo University

AIM: To develop a mathematical model for the early detection of hepatocellular carcinoma (HCC) with a panel of serum proteins in combination with α-fetoprotein (AFP).METHODS: Serum levels of interleukin (IL)-8, soluble intercellular adhesion molecule-1 (sICAM-1), soluble tumor necrosis factor receptor II (sTNF-RII), proteasome, and β-catenin were measured in 479 subjects categorized into four groups: (1) HCC concurrent with hepatitis C virus (HCV) infection (n = 192); (2) HCV related liver cirrhosis (LC) (n = 96); (3) Chronic hepatitis C (CHC) (n = 96); and (4) Healthy controls (n = 95). The R package and different modules for binary and multi-class classifiers based on generalized linear models were used to model the data. Predictive power was used to evaluate the performance of the model. Receiver operating characteristic curve analysis over pairs of groups was used to identify the best cutoffs differentiating the different ***: We revealed mathematical models, based on a binary classifier, made up of a unique panel of serum proteins that improved the individual performance of AFP in discriminating HCC patients from patients with chronic liver disease either with or without cirrhosis. We discriminated the HCC group from the cirrhotic liver group using a mathematical model (-11.3 + 7.38 × Prot + 0.00108 × sICAM + 0.2574 × β-catenin + 0.01597 × AFP) with a cutoff of 0.6552, which achieved 98.8% specificity and 89.1% sensitivity. For the discrimination of the HCC group from the CHC group, we used a mathematical model [-10.40 + 1.416 × proteasome + 0.002024 × IL + 0.004096 × sICAM-1 + (4.251 × 10-4) × sTNF + 0.02567 × β-catenin + 0.02442 × AFP] with a cutoff 0.744 and achieved 96.8% specificity and 89.7% sensitivity. Additionally, we derived an algorithm, based on a binary classifier, for resolving the multi-class classification

关键词： Mathematical model Hepatocellular carcinoma α -fetoprotein Soluble intercellular adhesion molecule-1 β -catenin Interleukin-8 Soluble tumor necrosis factor receptor II Proteasome

过渡金属阳离子预处理对活性炭催化性能的提高

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催化学报 2007年第7期28卷 611-616页

作者： Sahar A. EL-MOLLA Gamil A. EL-SHOBAKY Sohair A. sayed ahmed 艾因沙姆萨大学教育学院化学系国家研究中心

首先将商用活性炭样品在1%的稀硝酸中处理,然后等体积浸渍在含有5%和10%（质量分数）硝酸钴、硝酸镍或硝酸铜的水溶液中,并在100 ℃干燥至恒重,最后将样品在Ar气氛中于400 ℃焙烧 3 h. 采用X射线衍射、N2吸附和红外光谱等分析手段对不... 详细信息

首先将商用活性炭样品在1%的稀硝酸中处理,然后等体积浸渍在含有5%和10%（质量分数）硝酸钴、硝酸镍或硝酸铜的水溶液中,并在100 ℃干燥至恒重,最后将样品在Ar气氛中于400 ℃焙烧 3 h. 采用X射线衍射、N2吸附和红外光谱等分析手段对不同固体样品进行了表征,并考察了其对异丙醇催化转化和25～45 ℃时过氧化氢催化分解的活性. 结果表明,掺杂5%或10%的过渡金属氧化物后,活性炭样品中含有结晶度很差的CoO, Co3O4, NiO, Cu2O和CuO相的纳米晶. 金属氧化物预处理使活性炭的BET比表面积略有增加. 这些固体样品主要用作脱氢催化剂,其选择性均高于90%. 在225 ℃时,经5%氧化钴、氧化镍和氧化铜处理的活性炭的催化活性比硝酸处理的活性炭分别提高了6%, 24.6%和40.6%. 少量CoO处理后的商用活性炭对H2O2催化分解活性的提高是由参与该催化反应的活性位浓度的显著增加而引起的,该处理过程并没有改变H2O2催化分解的机理.

关键词：活性炭过渡金属阳离子掺杂异丙醇转化过氧化氢分解