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方形截面RC构件及其CFRP加固构件在横向冲击作用下动力响应对比研究

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方形截面RC构件及其CFRP加固构件在横向冲击作用下动力响应对比研...

作者： ZAIDI khaled MALEH hussein MOHAMMED 西南交通大学

学位级别：硕士

钢筋混凝土框架结构是高铁站房常用结构类型之一。站房结构柱在其生命周期中,可能会遭遇来自脱轨列车等偶然荷载的撞击作用,从而引起钢筋混凝土柱发生严重破坏,甚至整个站房结构的连续倒塌,给人们的生命安全和国家财产造成巨大损失。近... 详细信息

钢筋混凝土框架结构是高铁站房常用结构类型之一。站房结构柱在其生命周期中,可能会遭遇来自脱轨列车等偶然荷载的撞击作用,从而引起钢筋混凝土柱发生严重破坏,甚至整个站房结构的连续倒塌,给人们的生命安全和国家财产造成巨大损失。近年来,利用碳纤维增强聚合物（CFRP）复合材料,提高结构构件的抗冲击性能已成为研究热点。本文以高铁站房常用典型钢筋混凝土结构柱以及碳纤维加固的钢筋混凝土结构柱为研究对象,主要研究内容和结果如下:（1）根据高铁站房钢筋混凝土结构、列车撞击点、列车撞击能量等因素,设计了5根方型截面钢筋混凝土柱试验构件FH1～FH5,并以FH2为基准构件,设计沿构件纵向包裹CFRP加强的试验构件FH2-Z1;设计了冲击锤冲击试验方案。（2）对FH1～FH5,FH2-Z1进行了不等跨（冲击点在2/9L处）冲击试验。试验研究结果表明:（1）钢筋混凝土试验构件FH1～FH5均表现为剪切破坏模式;各构件冲击力时程曲线均由平值段、平台段、下降段构成;随着冲击高度的增大,冲击力峰值增大,但平台值变化不明显;随着纵向配筋率增大,冲击力平台值稍有增大,持时缩短;随着配=箍率加大,平台段更为平稳,波动减少;轴压比影响较大,使平台段迅速缩短。（2）对CFRP加固的FH2-Z1构件,与相应FH2相比,其破坏模式总体表现为受弯状态,冲击力峰值减少,平台值变化不大,平台段持时缩短。（3）为进一步研究CFRP的作用,建立了有限元模型。与试验结果对比,验证了模型的正确性。通过对比分析弯矩时程、剪力时程、CFRP应变时程。分析结果表明,在冲击过程中,RC构件临界截面（冲击点截面）的剪力在达到峰值后立即下降,丧失了大部分承载力,截面不能形成有效弯矩;在整个构件范围内,钢筋的主要应变集中在箍筋处;FRP加固的钢筋混凝土构件的抗弯剪强度增加,达到峰值后,CERP-RC构件的弯矩和剪力保持在较高水平,然后开始下降,直至纵筋断裂。进一步验证了CFRP加固的FH2-Z1,由原有FH2的剪切模式,转变为弯曲破坏模式。（4）运用有限元分析了参数对FH2及FH2-Z1的撞击性能影响,参数包括冲击速度、配筋率。结果表明,冲击速度和纵向配筋率的变化不会改变两构件的破坏机理,钢FH2为剪切破坏,FH2-Z1为弯曲破坏;但随着冲击速度和纵向配筋率的增大,可以有效地改善CFRP-RC构件的冲击性能,减小构件的挠度。

关键词：横向冲击方形截面混凝土构件 FRP加固动力响应破坏模式

The Multiplicative Analytic Hierarchy Process (MIAHP) as a Quality Criterion Determining the Technological Value of the Egyptian Cotton Varieties

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American Journal of Plant Sciences 2010年第2期1卷 106-112页

作者： khaled M. hussein AbdElbaset A. Hassan Mostafa M. Kamal 不详

This study was undertaken to develop a numerical process that can be used as a quality criterion to determine the technological value of the Egyptian cotton varieties, which in turn would denote the end-use of their fibers. However the material used in the study comprised the 6 Egyptian cotton varieties Giza70, Giza80, Giza86, Giza88, Giza90 and Giza92. According to the local practice in Egypt, Giza70, Giza88 and Giza92 belong to the Extra-Long Staple (ELS) category, while Giza80, Giza86 and Giza90 are included under the Long Staple (LS) category. The regression analysis of the relationships between fiber properties and yarn skein strength (lea product) of the 2 carded ring counts 40 and 50 Ne, was employed to drive an equation for calculating the Multiplicative Analytic Hierarchy Process (MIAHP) values. The values of the MIAHP have been used as numerical determinations of the technological values of the Egyptian cotton varieties. Nevertheless, the findings of this study clarified that with respect to the criteria weights, the pair-wise comparisons denoted that fiber length properties of Egyptian cotton ranked first where they revealed the most dominant effect on yarn strength, while tensile properties ranked second with a relative weight close to that of fiber length. On the contrary, the relative weight of fiber fineness (micronaire reading) was found to be marginal. With regard to the relative weight of sub-criterion, the pair-wise comparisons indicated that the role of fiber tenacity as a determinant of yarn strength is much superior to that of fiber elongation. Further the global weights of the sub-criterion of fiber length pointed out that the UHML (upper half mean length) plays an important role in determining yarn strength of the Egyptian cotton comparing with either the UI (uniformity index) or the SFC (short fiber content). In conformity with the values of the MIAHP, it was found that in the order of descending rank, Giza88 ranked first, followed by Giza92

关键词： Analytic Hierarchy Process Cotton Fiber Quality Technological Value

Near-zero stiffness accelerometer with buckling of tunable electrothermal microbeams

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Microsystems & Nanoengineering 2024年第2期10卷 67-81页

作者： hussein hussein Chen Wang Rui Amendoeira Esteves Michael Kraft Hossein Fariborzi Department of Mechanical Engineering MSFEAAmerican University of BeirutBeirut11072020Lebanon King Abdullah University of Science and Technology Thuwal23955-6900Saudi Arabia ESAT-MNS University of Leuven3001LeuvenBelgium

Pre-shaped microbeams,curved or inclined,are widely used in MEMS for their interesting stiffness *** mechanisms allow a wide range of positive and negative stiffness tuning in their direction of motion.A mechanism of pre-shaped beams with opposite curvature,connected in a parallel configuration,can be electrothermally tuned to reach a near-zero or negative stiffness behavior at the as-fabricated *** simple structure helps incorporate the tunable spring mechanism in different designs for accelerometers,even with different transduction *** sensitivity of the accelerometer can be considerably increased or tuned for different applications by electrothermally changing the stiffness of the spring *** inclined beams are implemented in a capacitive micromachined *** measurements on fabricated prototypes showed more than 55 times gain in sensitivity compared to their initial *** experiments showed promising results in enhancing the resolution of acceleration sensing and the potential to reach unprecedent performance in micromachined accelerometers.

关键词： properties. mechanism. stiffness

Predictive Value of Neutrophil-to-Lymphocyte Ratio in Outcomes of Patients with Acute Coronary Syndrome

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World Journal of Cardiovascular Diseases 2018年第5期8卷 265-275页

作者： Wassam Eldin Hadad El Shafey Ahmed Mohamed Emara Walaa Farid Mosa khaled hussein El-Sharnouby Department of Cardiology Menoufia University Hospitals Menoufia Egypt Department of Cardiology Shibin El Kom Teaching Hospital Menoufia Egypt

Objectives: Previous studies have demonstrated the role of inflammation in acute coronary syndrome (ACS). The neutrophil-to-lymphocyte ratio (NLR) was found to be a useful inflammatory marker for predicting adverse outcomes. We hypothesized that an elevated neutrophil-to-lymphocyte ratio would be associated with increased mortality in patients with acute coronary syndrome. Methods: The study consisted of 40 patients with acute coronary syndrome who were admitted to Cardiology Department—Menoufia University Hospitals. The primary endpoint was all-cause in-hospital as well as 30-day mortality, and the patients were divided into three tertiles according to their admission NLR results. Results: All-cause 30-day mortality in the three groups based on NLR was 0.0%, 7.7% and 28.6%, in the low-, middle- and high-NLR groups, respectively (P χ2 test). In a logistic regression analysis, including baseline demographic, clinical, and biochemical covariates, the neutrophil-to-lymphocyte ratio was an independent predictor of mortality (OR = 2.44, 95% CI = 1.185 - 5.007, P Conclusion: An elevated neutrophil-to-lymphocyte ratio (NLR), a simple, relatively inexpensive and universally available inflammatory marker, seems to be a predictor of 30-day mortality in patients with acute coronary syndrome.

关键词： Acute Coronary Syndrome Inflammation Ischemia Neutrophil-to-Lymphocyte Ratio Mortality

Correlation between SYNTAX Score and Pattern of Risk Factors in Patients Referred for Coronary Angiography in Cardiology Department, Menoufia University

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World Journal of Cardiovascular Diseases 2018年第8期8卷 431-439页

作者： Ahmed Mokhtar El Kersh Ahmed Ashraf Reda Mohamed Gamal El Hadad khaled hussein El-Sharnouby Department of Cardiology Menoufia University Hospitals Menoufia Egypt Department of Cardiology Shibin El Kom Teaching Hospital Menoufia Egypt

Objectives: The role of SYNTAX (SX) score in assessing the complexity of coronary artery disease (CAD) is well established. In this study we investigate the relationship between conventional risk factors of CAD with its complexity using SX score. Methods: The study consisted of 52 patients with CAD who were admitted to Cardiology Department—Menoufia University Hospitals for elective coronary angiography. The overall SX score was calculated prospectively using the SX score algorithm. Then comparison was done between populations with and without each risk factor. Results: There was a statistically significant correlation between age, hypertension, diabetes mellitus, dyslipidemia and smoking with SX score results (p 0.05). In a multivariate regression analysis, including conventional risk factors of CAD as independent covariates, it revealed that aging, having diabetes mellitus and smoking were identified as significant independent risk factors for CAD complexity. Conclusion: Advanced age, having diabetes mellitus and cigarette smoking are considered to be independent risk factors for the complexity of CAD. Therefore, when these factors present, we expect that the SX score of the patient to be high indicating a complex CAD.

关键词： Coronary Artery Disease SYNTAX Score Risk Factors

Synthesis and characterization of nanocarbon from waste batteries via an eco-friendly method

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Waste Disposal and Sustainable Energy 2024年第2期6卷 197-208页

作者： Maraim Kh.Uoda hussein Q.hussein Rana R.Jalil Chemical Engineering Department College of EngineeringUniversity of BaghdadBaghdadIraq Thi.Qar Oil Company NassriyaIraq Petroleum Research and Development Center BaghdadIraq

The widespread use of disposable batteries to power common electronic devices is a major source of *** are growing environmental and health concerns due to the expansion of e-waste around the ***,developing a reli-able system for recycling old batteries has reached the top of the recycling priority *** current study presents a novel approach to synthesis carbon nanoparticles(CNPs)from spent batteries via an eco-friendly method that offers economical,environment-friendly,and nontoxic approaches in comparison to conventional chemical *** synthesized nano-particles were characterized by field emission scanning electron microscopy(FE-SEM),energy-dispersive X-ray(EDX),powder X-ray diffractometry(XRD),UV-VIS absorption analysis(UV),Fourier transform infrared spectroscopy(FT-IR),Atomic force microscope(AFM),and thermo-gravimetric analysis(TGA).The average diameter of the synthesized particles was 40.16 nm,and the particles tended to be aspherical in *** analysis also predicted the presence of pure carbon,with some contamination arrived at 15%(in weight).This is a novel study in which nanocarbons were synthesized in a brine(7600x10-6)from a target(CNPs>75 nm),which paves the way for future use of CNPs derived from spent batteries and helps the environment by decreasing the amount of electronic waste dumped in landfills.

关键词： Novel Zn-C battery Carbon nanoparticles Characterization Eco-friendly methods

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联合手术方法治疗儿童先天性马蹄内翻足

临床骨科杂志 2006年第5期9卷 431-432页

作者：苏仕奎 khaled Zain hussein 巢湖市第二人民医院骨科安徽巢湖238000 Alarzi Hospital AbyonRepublic of YemenP.O.Box3107

目的探讨联合手术方法治疗小儿先天性马蹄内翻足。方法18例33足先天性马蹄内翻足患儿。采用联合手术方法包括跟腱冠状位延长、胫前肌移位、足内侧短缩软组织切开、跖筋膜切断和骰骨内“V”形截骨。结果14例25足获得随访。随访时间6～18... 详细信息

目的探讨联合手术方法治疗小儿先天性马蹄内翻足。方法18例33足先天性马蹄内翻足患儿。采用联合手术方法包括跟腱冠状位延长、胫前肌移位、足内侧短缩软组织切开、跖筋膜切断和骰骨内“V”形截骨。结果14例25足获得随访。随访时间6～18月,平均7月。优良13例24足,1例1足手术效果差。结论联合手术方法治疗儿童先天性马蹄内翻足具有减少手术次数、短期无复发的优点。

关键词：儿童畸形足/外科学联合手术

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有关蛋鸡支原体感染治疗的新见解

国外畜牧学（猪与禽） 2017年第10期37卷 19-20页

作者：章薇邵建忠何闪 khaled hussein 安徽省农业科学院畜牧兽医研究所

商品蛋的品顺受到诸多因素的影响，包括营养、疾病状况（鸡滑液囊支原体和传染性支气管炎病毒感染）以及饲养管理措施等。大部分因素已为人熟知，并且多年来已经有17充分的记录。

关键词：支原体感染传染性支气管炎病毒感染蛋鸡鸡滑液囊支原体治疗饲养管理营养病状

A reinforcement learning approach for thermostat setpoint preference learning

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Building Simulation 2024年第1期17卷 131-146页

作者： hussein Elehwany Mohamed Ouf Burak Gunay Nunzio Cotrufo Jean-Simon Venne Department of Environmental Engineering Carleton UniversityOttawaCanada Departmentof Building Civiland Environmental EngineeringConcordia UniversityMontrealCanada BrainBox Al Inc. MontrealCanada

Occupant-centric controls(OcC)is an indoor climate control approach whereby occupant feedback is used in the sequence of operation of building energy *** OcC has been used in a wide range of building applications,an OcC category that has received considerable research interest is learning occupants'thermal preferences through their thermostat interactions and adapting temperature setpoints *** recent studies used reinforcement learning(RL)as an agent for OcC to optimize energy use and occupant *** studies depended on predicted mean vote(PMV)models or constant comfort ranges to represent comfort,while only few of them used thermostat *** paper addresses this gap by introducing a new off-policy reinforcement learning(RL)algorithm that imitates the occupant behaviour by utilizing unsolicited occupant thermostat *** algorithm is tested with a number of synthetically generated occupant behaviour models implemented via the Python APl of *** simulation results indicate that the RL algorithm could rapidly learn preferences for all tested occupant behaviour scenarios with minimal exploration *** substantial energy savings were observed with most occupant scenarios,the impact on the energy savings varied depending on occupants'preferences and thermostat use behaviour stochasticity.

关键词： reinforcement learning preference learning occupant-centric controls smart thermostats off-policy learning