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Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio

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Frontiers of Structural and Civil Engineering 2021年第6期15卷 1400-1414页

作者： tarek uddin mohammed Aziz Hasan MAHMOOD Mohammad Zunaied-Bin-HARUN Jamil Ahmed JOY MdAsif AHMED Department of Civil and Environmental Engineering Islamic University of Technology(IUT)Organization of Islamic Cooperation(OIC)Board BazarGazipur 1704Bangladesh Centre for Infrastructure Engineering and Safety School of Civil and Environmental EngineeringThe University of New South WalesSydneyNSW 2052Australia Department of Civil Engineering European University of BangladeshMirpurDhaka 1216Bangladesh

Aggregates are the biggest contributor to concrete volume and are a crucial parameter in dictating its mechanical *** such,a detailed experimental investigation was carried out to evaluate the effect of sand-toaggregate volume ratio(s/a)on the mechanical properties of concrete utilizing both destructive and non-destructive testing(employing UPV(ultrasonic pulse velocity)measurements).For investigation,standard cylindrical concrete samples were made with different s/a(0.36,0.40,0.44,0.48,0.52,and 0.56),cement content(340 and 450 kg/m^(3)),water-to-cement ratio(0.45 and 0.50),and maximum aggregate size(12 and 19 mm).The effect of these design parameters on the 7,14,and 28 d compressive strength,tensile strength,elastic modulus,and UPV of concrete were *** careful analysis demonstrates that aggregate proportions and size need to be optimized for formulating mix designs;optimum ratios of s/a were found to be 0.40 and 0.44 for the maximum aggregate size of 12 and 19 mm,respectively,irrespective of the W/C(water-to-cement)and cement content.

关键词： aggregates non-destructive testing sand-to-aggregate volume ratio(s/a) maximum aggregate size(MAS)

Power system voltage instability risk mitigation via emergency demand response-based whale optimization algorithm

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Protection and Control of Modern Power Systems 2019年第1期4卷 295-308页

作者： mohammed Amroune tarek Bouktir Ismail Musirin Department of Electrical Engineering University of Ferhat Abbas Setif 119000SetifAlgeria Faculty of Electrical Engineering Universiti Teknologi MARA40450Shah AlamMalaysia

In recent years, due to the economic and environmental issues, modern power systems often operate proximately to the technical restraints enlarging the probable level of instability risks. Hence, efficient methods for voltage instability prevention are of great importance to power system companies to avoid the risk of large blackouts. In this paper, an event-driven emergency demand response (EEDR) strategy based on whale optimization algorithm (WOA) is proposed to effectively improve system voltage stability. The main objective of the proposed EEDR approach is to maintain voltage stability margin (VSM) in an acceptable range during emergency situations by driving the operating condition of the power system away from the insecure points. The optimal locations and amounts of load reductions have been determined using WOA algorithm. To test the feasibility and the efficiency of the proposed method, simulation studies are carried out on the IEEE 14-bus and real Algerian 114-bus power systems.

关键词： Voltage stability Emergency demand response Whale optimization algorithm Blackouts

Cutaneous leishmaniasis in Al Hassa, Saudi Arabia: Epidemiological trends from 2000 to 2010

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Asian Pacific Journal of Tropical Medicine 2013年第8期6卷 667-672页

作者： tarek Tawfik Amin Hamdan Ibrahim Al-mohammed Feroze Kaliyadan Balghonaim Salah mohammed King Faisal University Cairo University Vector Control Unit Preventive Medicine Department Local Health Directorate Al Hofuf Ministry of Health

Objective: To study epidemiological trends related to cutaneous leishmaniasis (CL) in Al Hassa, an endemic area in Saudi Arabia. Methods: This retrospective study included the spatial/ temporal analysis of the reported cases of CL using the available surveillance database for the disease at the regional Vector Control Unit, from 2000 to 2010. Results: The incidence of CL was declining at a stable rate especially during the last 3 years of the study (2008-2010). An interesting finding was the percentage of expatriates affected was increasing over the last 10 years compared to that of the Saudis. Conclusions: A definite declining trend in the incidence of CL was observed in Al Hassa. Further studies are warranted to assess whether special public health measures are needed for better control of CL in expatriate populations in Saudi Arabia.

关键词： Cutaneous leishmaniasis Epidemiology Saudi Arabia

Advancing sandstone reservoir compressibility prediction:A correlation-driven methodology

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Petroleum Research 2024年第2期9卷 273-279页

作者： tarek Ganat Meftah Hrairi Amr Badawy Vahid Khosravi mohammed Abdalla Department of Petroleum Chemical Engineering Sultan Qaboos UniversityP.O.Box 50Al-Khod123MuscatOman Department of Mechanical and Aerospace Engineering International Islamic University MalaysiaP.O.Box 1050728Kuala LumpurMalaysia Reservoir Engineering Section Petronas Carigali SDN BHDP.O.Box 10500088Kuala LumpurMalaysia Department of Chemical and Petroleum Engineering Faculty of EngineeringTechnologyand Built EnvironmentUCSI University56000Kuala LumpurMalaysia Chemical&Petroleum Engineering United Arab Emirates UniversityP.O.Box No.15551Al AinUAE

This study presents a correlation-based approach for predicting the compressibility of sandstone reservoir *** study proposes a matrix of new empirical equations that significantly improve the precision of measuring the pore volume compressibility,with the most optimal fit of results based on a cubic polynomial *** accuracy of the calculations was validated through comparison with actual data using root mean square method,and the suggested correlations significantly enhance the precise prediction of rock compressibility in sandstone *** this study,the source of data collection is consolidated and unconsolidated sandstone from East Asia offshore ***,variations in compressibility with net overburden pressure over the course of the field's lifespan have been *** results demonstrate the application of regression analysis in establishing a network of linkages between independent and dependent *** proposed correlations for consolidated and unconsolidated sandstones offer a remarkable improvement in the accurate calculation of rock compressibility compared to traditional laboratory procedures,with an average error of 2.5%compared to 5-10%for laboratory *** approach of this study offers a cost-effective and time-efficient alternative to remarkedly enhance the overall performance of sandstone reservoirs in the oil and gas industry.

关键词： Compressibility Consolidated and unconsolidated sandstone Rock properties Rock mechanics

Prevalence of intestinal parasitic infections and its relationship with socio-demographics and hygienic habits among male primary schoolchildren in Al-Ahsa,Saudi Arabia

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Asian Pacific Journal of Tropical Medicine 2010年第11期3卷 906-912页

作者： Hamdan Ibrahim Al-mohammed tarek Tawfik Amin Elsayed Aboulmagd Hatem Refaat Hablus Burhan Omar Zaza Department of Medical Microbiology and Parasitology College of MedicineKing Faisal UniversitySaudi Arabia Department of Community Medicine Faculty of MedicineCairo UniversityEgypt Department of Paediatrics College of MedicineKing Faisal UniversitySaudi Arabia Technical Director School Health Preventive ServicesMinistry of EducationAl-Hofuf DirectorateSaudi Arabia

Objective:To investigate the prevalence of different intestinal parasitic infections among male primary schoolchildren in Al-Ahsa,Saudi Arabia,and to explore the possible relative socioeconomic, environmental and behavioural sanitary ***:A cross-sectional descriptive study was performed.A total of 1 289 male students aged from 7 to 12 years were selected randomly from 20 urban and 12 rural primary schools by multistage sampling method. Data collection was carried out by self administered questionnaire form to the parents/guardians of students and included inquires about socio-demographics,environmental conditions,and behavioural sanitary *** analysis was carried out to examine the presence of intestinal parasitic ***:Overall prevalence of parasitic infections was 27.2%,more among rural *** encountered infections included Entamoeba histolytica/dispar(8.2%), Giardia lamblia(6.5%),Entamoeba coli(4.0%) and Enterobius vermicularis(1.6%).Logistic regression revealed that lower maternal educational level and occupational status,low family income,big family size,poor personal hygienic practices and positive history of previous intestinal infections among family members increased the likelihood of ***: Although of low magnitude,intestinal parasitic infections still represent a public health concern among male schoolchildren in Al-Ahsa ***-demographic and poor personal hygienic habits are the main predictors for these infections.

关键词： Intestinal parasitic infections Schoolchildren Epidemiological correlates Hygiene Saudi Arabia

Probing Nucleon Structure in Deep Inelastic Scattering

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Journal of Applied Mathematics and Physics 2015年第5期3卷 608-622页

作者： mohammed Sultan Al-Buriahi mohammed tarek Hussein mohammed Tawfik Ghoneim Faculty of Science Cairo University Cairo Egypt

The comparison between the muon and the neutrino as probes of the nucleon structure is presented. The prediction of the structure functions, quark distributions, leptonic currents, and cross section led us to obtain some of the features of the electro-weak interactions in the deep inelastic scattering. A perturbation technique is used to evaluate the leptonic current that is assumed to be a complex quantity. The imaginary part of which represents the rate of absorption. On the other hand, the quarks wave functions forming the nucleon are extracted from experimental data for neutrino-nucleon and muon-nucleon collisions. A numerical technique is applied to analyze the data of the experiments CERN-NA-2 and CERN-WA25, to evaluate the quark functions and hence to calculate the hadronic current. It is found that the quark distribution functions predicted by the muon as a probe is slightly shifted up compared with that of the neutrino. Finally, the differential cross section is calculated in terms of leptonic and hadronic currents.

关键词： Lepton-Nucleon Interactions Deep Inelastic Structure Function Quark Functions

Type-2 Fuzzy Extended Kalman Filter for Dynamic Security Monitoring Based on Novel Sensor Fusion

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Journal of Intelligent Learning Systems and Applications 2012年第3期4卷 159-168页

作者： tarek Dakhlallah mohammed Zohdy Omar Salim Electrical Engineering Department Benha University Benha Egypt. School of Engineering and Computer Science Oakland University Rochester USA

In this paper, we have focused on several relevant sensors [Laser (for speed measurements), Sonar (for space scanning) and RF (for access rights)] to cooperate in monitoring the security status of multiple dynamic agent in surveillance area. Such coordination is achieved by employing novel concepts of sensors similarity and complementarity. Furthermore, this system is aided with Extended Kalman Filter (EKF) in order to estimate the agent’s non-linear movement. Finally, transforms system state to be able to make a security suspiciousness decision by using type-2 fuzzy logic system to handle uncertainty. It is shown that the system performance can exhibit promising improvements for this dynamic security monitoring application.

关键词： Sensor Similarity Sensor Complementarity Type-2 Fuzzy

Development and characterization of a regional lunar soil simulant for emirates lunar missions

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International Journal of Mining Science and Technology 2024年第9期34卷 1305-1315页

作者： Bo Peng Prabu Thannasi Waleed El-Sekelly tarek Abdoun Kemal Celik Division of Engineering New York University Abu DhabiAbu Dhabi PO Box 129188United Arab Emirates Structural Engineering Department Faculty of EngineeringMansoura UniversityMansoura 35516Egypt

Lunar soil simulants(LSS)have been pivotal in the success of past and current lunar *** have enhanced the design of lander and rover wheels through interaction studies on the lunar testbed under simulated environmental *** have also been used to evaluate the geotechnical,geomechanical,and dynamic characteristics of the lunar soil(LS),which is vital for future lunar *** most simulants have focused on either the chemical and mineralogical or geotechnical properties,developing a comprehensive LSS that mimics the lunar soil is of paramount importance for lander and rover soft-landing and future lunar *** article presents the significant development and characterization of the new LSS NYUAD-1,the first regional soil simulant tailored for the planned Emirates lunar *** material and geotechnical properties of NYUAD-1,including chemical composition,mineralogy,particle size,morphology,specific gravity,density,shear strength,and compressibility behaviors,were assessed through laboratory tests conducted per ASTM *** analysis with authentic lunar regolith and various regolith simulants confirms the significance and applicability of NYUAD-1 for lunar-based research,offering a promising step toward future lunar habitation.

关键词： LSS Chemical composition Mineralogy Density Shear strength Compressibility

Removing Iron Ions Contaminants from Groundwater Using Modified Nano-Hydroxyapatite by Nano Manganese Oxide

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Journal of Water Resource and Protection 2019年第6期11卷 789-809页

作者： mohammed Abd-El-Aal Ahmed Ayash tarek Ahmed Seaf Elnasr Madiha Hassan Soliman Sohag Company for Water and Waste Water Dar El Salam Sohag Egypt Chemistry Department Faculty of Science Al-Azhar University Assiut Egypt Chemistry Department Collage of Science Jouf University KSA Chemistry Department Faculty of Science Helwan University Cairo Egypt

In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), Elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = ?51 KJ/mol, and ΔS = ?142 (KJ/mol)) for the adsorption process were also calculated and discussed.

关键词： Groundwater Adsorption Nano Materials Hydroxyapatite Manganese Oxide Iron Ions Kinetic Thermodynamic