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Effect of earth reinforcement,soil properties and wall properties on bridge MSE walls

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Frontiers of Structural and Civil Engineering 2021年第5期15卷 1209-1221页

作者： Zaid MOMANI Eyosias BENEBERU nur YAZDANI Department of Civil Engineering Al-Ahliyya Amman UniversityAmman 19328Jordan Bridgefarmer&Associates DallasTX 75234USA Department of Civil Engineering University of Texas at ArlingtonArlingtonTX 76019USA

Mechanically stabilized earth(MSE)retaining walls are popular for highway bridge *** have precast concrete panels attached to earth *** panels are designed to have some lateral ***,in some cases,excessive movement and even complete dislocation of the panels have been *** this study,3-D numerical modeling involving an existing MSE wall was undertaken to investigate various wall *** effects of pore pressure,soil cohesion,earth reinforcement type and length,breakage/slippage of reinforcement and concrete strength,were *** showed that the wall movement is affected by soil pore pressure and reinforcement integrity and length,and unaffected by concrete *** cohesion has a minor effect,while the movement increased by 13–20 mm for flexible geogrid reinforced walls compared with the steel grid *** steel grid stresses were below yielding,while the geogrid experienced significant stresses without *** reinforcement may be used taking account of slippage resistance and wall *** steel grid is used,non-cohesive soil is recommended to minimize *** soil drainage is important for control of pore pressure.

关键词： mechanically stabilized earth walls precast concrete panels backfill soil finite element modeling earth reinforcement

The development of ultralightweight expanded perlite-based thermal insulation panel using alkali activator solution

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Frontiers of Structural and Civil Engineering 2022年第11期16卷 1486-1499页

作者： Damla nur CELIK Gökhan DURMUŞ Civil Engineering Department Technology FacultyGazi UniversityAnkara 06500Turkey

The International Energy Agency(IEA)states that global energy consumption will increase by 53%by *** has 70%of the world’s perlite reserves,and in order to reduce energy consumption a thermal insulation panel was developed in Turkey using different particle sizes of expanded perlite(EP).In this study,0–1.18 mm(powder)and 0–3 mm(granular)EP particle sizes were selected,since they have the lowest thermal conductivity coefficients among all the particle *** addition,an alkali activator solution was used as a binder in the *** alkaline activator solution was obtained by mixing sodium hydroxide solution(6,8,10,and 12 mol·L−1)and sodium silicate(Module 3)at the different ratios of Na2SiO3 to NaOH of 1,1.5,2,and *** study aimed to experimentally determine the optimum binder and distribution ratio of EP,with the lowest coefficient of thermal conductivity and the lowest *** lowest thermal conductivity and the lowest density were determined as 0.04919 W·m−1·K−1 and 133.267 kg/m3,respectively,in the sample prepared with 83.33%powder-size EP,6 mol·L−1 sodium hydroxide solution,and ratio of Na2SiO3 to NaOH of *** density,thermal conductivity,and compressive strength of the sample showed the same trends of behavior when the Na2SiO3 to NaOH ratio was *** addition,the highest compressive strength was measured in 12 mol·L−1 NaOH concentration regardless of particle *** conclusion,the study predicts that the EP-based thermal insulation panel can be used as an insulation material in the construction industry according to the TS825 Thermal Insulation Standard.

关键词： expanded perlite alkali activator thermal insulation panel thermal conductivity

New structures for closed-form wave solutions for the dynamical equations model related to the ion sound and Langmuir waves

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Communications in Theoretical Physics 2021年第3期73卷 1-13页

作者： Md nur Alam M S Osman Department of Mathematics Pabna University of Science and TechnologyPabna6600Bangladesh Department of Mathematics Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Mathematics Faculty of Applied ScienceUnrni Alqura UniversityMakkah 21955Saudi Arabia

This treatise analyzes the coupled nonlinear system of the model for the ion sound and Langmuir *** modified(G'/G)-expansion procedure is utilized to raise new closed-form wave *** solutions are investigated through hyperbolic,trigonometric and rational *** graphical design makes the dynamics of the equations *** provides the mathematical foundation in diverse sectors of underwater acoustics,electromagnetic wave propagation,design of specific optoelectronic devices and physics quantum ***,we concluded that the studied approach is advanced,meaningful and significant in implementing many solutions of several nonlinear partial differential equations occurring in applied sciences.

关键词： the modified(G'/G)-expansion method ion sound wave Langmuir wave closed-form wave solutions

The study on nuclear level density of some deformed Dy radionuclides using collective model approach

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Nuclear Science and Techniques 2016年第5期27卷 225-230页

作者： Sabahattin Akbas Seref Okuducu Nisa nur Akti Science and Technology Application and Research Centre Bozok University 66200 Yozgat Turkey Department of Physics Faculty of Science Gazi University 06500 Ankara Turkey Saraykoy Nuclear Research and Training Centre 06983 Ankara Turkey

Nuclear level density(NLD) is a characteristic property of many-body quantum mechanical *** are of special importance to make statistical calculations in reactor studies and various theoretical and experimental nuclear physics and engineering *** this study,we have investigated a set of particle states in distinct rotational and vibrational bands to calculate nuclear level density parameters and the NLDs of accessible states of some deformed Dy radionuclides using a collective model approach,which included different excitation bands of the observed nuclear *** method used assumes equidistant spacing of collective coupled state bands of the considered *** results of the calculated NLD have been compared with the experimental and compiled data obtained by the Oslo group,shell model Monte Carlo,Hartree-Fock-Bogoliubov + combinatorial approach,Bardeen-Cooper-Schrieffer approach and are in a good agreement.

关键词：核能级密度参数放射性核素集体模型变形实验核物理量子力学系统计算结果 Cooper

Microwave-assisted solvent extraction of castor oil from castor seeds

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2516-2522页

作者： nur Atirah Ibrahim Muhammad Abbas Ahmad Zaini Centre of Lipids Engineering & Applied Research (CLEAR) Ibnu-Sina Institute for Scientific & Industrial Research Universiti Teknologi Malaysia 81310 UTM Johor Bahru Johor Malaysia School of Chemical & Energy Engineering Faculty of Engineering Universiti Teknologi Malaysia

This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed(S/F, ml of solvent to gram of feed) *** process parameters were optimized by statistical approach using historical data design of response surface method(RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield.

关键词： Castor seed Castor oil Dielectric properties Microwave-assisted solvent extraction Oxidation stability

SPT based determination of undrained shear strength:Regression models and machine learning

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 185-198页

作者： Walid Khalid MBARAK Esma nur CINICIOGLU Ozer CINICIOGLU Department of Civil Engigeering Bogazici UniversityIstanbul 34342Turkey School of Business Quantitative Methods DivisionIstanbul UniversityIstanbul 34320Turkey

The purpose of this study is the accurate prediction of undrained shear strength using Standard Penetration Test results and soil consistency indices,such as water content and Atterberg *** this study,along with the conventional methods of simple and multiple linear regression models,three machine learning algorithms,random forest,gradient boosting and stacked models,are developed for prediction of undrained shear *** models are employed on a relatively large data set from different projects around Turkey covering 230 *** an improvement over the available studies in literature,this study utilizes correct statistical analyses techniques on a relatively large database,such as using a train/test split on the data set to avoid overfitting of the developed ***,the validity and consistency of the prediction results are ensured with the correct use of statistical measures like p-value and cross-validation which were missing in previous *** compare the performances of the models developed in this study with the prior ones existing in literature,all models were applied on the test data set and their performances are evaluated in terms of the resulting root mean squared error(RMSE)values and coefficient of determination(R^2).Accordingly,the models developed in this study demonstrate superior prediction capabilities compared to all of the prior ***,to facilitate the use of machine learning algorithms for prediction purposes,entire source code prepared for this study and the collected data set are provided as supplements of this study.

关键词： undrained shear strength linear regression random forest gradient boosting machine learning standard penetration test

Temperature variability caused by internal tides in the coastal waters of east coast of Peninsular Malaysia

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Acta Oceanologica Sinica 2019年第1期38卷 22-31页

作者： nur Hidayah Roseli Mohd Fadzil Akhir Institute of Oceanography and Environment Universiti Malaysia Terengganu

The effects of tidal currents(i.e., barotropic and internal tides) are important in the biogeochemistry of a coastal shelf sea. The high-frequency of currents and near-bottom temperatures collected in three consecutive southwest monsoon seasons(May, June, July and August of 2013 until 2015) is presented to reveal the role of the tidal currents to the temperature variability in the coastal shelf sea of the east coast of Peninsular Malaysia(ECPM),south of the South China Sea(SCS). The results of a spectral density and harmonic analysis demonstrate that the near-bottom temperature variability and the tidal currents are influenced by diurnal(O_1 and K_1) and semidiurnal(M_2) tidal currents. The spectral density of residual currents(detided data) at 5, 10 and 16 m depth also shows significant peaks at the diurnal tidal frequency(K_1) and small peaks at the semidiurnal tidal frequency(M_2)indicating the existence of internal tides. The result of the horizontal kinetic energy(HKE) shows a strong intermittent energy of internal tides in the ECPM with the strongest energy is found at 16 m depth during a sporadic cooling event in June and July. A high horizontal cross-shore heat flux(16 m) also indicates strong intrusions of cooler water into the ECPM in June and July. During the short duration of cold pulse water observed in June and July, a cross-wavelet analysis also reveals the strong relationship between the near-bottom temperatures and the internal tidal currents at the diurnal tidal frequency. The intrusion of this cooler water is probably related to the monsoon-induced upwelling in June. It is loosely interpreted that the interaction between the strong barotropic tides and the steep slope in the central basin of the SCS under the stratified condition in southwest monsoon has generated these internal tides. The dissipation of internal tides from the slope area probably has driven the cold-upwelled water into the ECPM coastal shelf sea when the upwelling intensity is th

关键词： east coast of Peninsular Malaysia South China Sea barotropic tidal currents internal tides nearbottom temperature coastal shelf sea

Synthesis of Zinc Oxide Nanostructures on Graphene/Glass Substrate via Electrochemical Deposition: Effects of Potassium Chloride and Hexamethylenetetramine as Supporting Reagents

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Nano-Micro Letters 2015年第4期7卷 317-324页

作者： nur Ashikyn Hambali Abdul Manaf Hashim Malaysia-Japan International Institute of Technology Universiti Teknologi Malaysia

The effects of the supporting reagents hexamethylenetetramine(HMTA)and potassium chloride(KCl)mixed in zinc nitrate hexahydrate(Zn(NO3)2 6H2O)on the morphological,structural,and optical properties of the resulting Zn O nanostructures electrodeposited on graphene/glass substrates were *** supporting reagent HMTA does not increase the density of nanorods,but it does remarkably improve the smoothness of the top edge surfaces and the hexagonal shape of the nanorods even at a low temperature of 75°***(OH-)ions from the HMTA suppress the sidewall growth of non-polar planes and promote the growth of Zn O on the polar plane to produce vertically aligned nanorods along the c *** contrast,the highly electronegative chlorine(Cl-)ions from the supporting reagent KCl suppress the growth of Zn O on the polar plane and promote the growth on non-polar planes to produce vertical stacking nanowall *** was found to be able to significantly improve the crystallinity of the grown Zn O structures,as indicated by the observation of much lower FWHM values and a higher intensity ratio of the emission in the UV region to the emission in the visible *** mixtures of Zn(NO3)2 6H2O and the supporting reagents HMTA and KCl seem to provide the optimum ratio of concentrations for the growth of high-density,uniform Zn O *** corresponding transmittances for such molar ranges are approximately 55–58%(HMTA)and 63–70%(KCl),which are acceptable for solar cell and optoelectronic devices.

关键词： Zinc oxide Electrochemical deposition Graphene Nanorod Nanowall

Improved Integrity Constraints Checking in Distributed Databases by Exploiting Local Checking

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Journal of Computer Science & Technology 2009年第4期24卷 665-674页

作者： Ali A.Alwan Hamidah Ibrahim nur Izura Udzir Department of Computer Science Faculty of Computer Science and Information TechnologyUniversiti Putra Malaysia 43400 SerdangMalaysia

Most of the previous studies concerning checking the integrity constraints in distributed database derive simplified forms of the initial integrity constraints with the sufficiency property, since the sufficient test is known to be cheaper than the complete test and its initial integrity constraint as it involves less data to be transferred across the network and can always be evaluated at the target site （single site）. Their studies are limited as they depend strictly on the assumption that an update operation will be executed at a site where the relation specified in the update operation is located, which is not always true. Hence, the sufficient test, which is proven to be local test by previous study, is no longer appropriate. This paper proposes an approach to checking integrity constraints in a distributed database by utilizing as much as possible the local information stored at the target site. The proposed approach derives support tests as an alternative to the existing complete and sufficient tests proposed by previous researchers with the intention to increase the number of local checking regardless the location of the submitted update operation. Several analyses have been performed to evaluate the proposed approach, and the results show that support tests can benefit the distributed database, where local constraint checking can be achieved.

关键词： distributed database integrity constraint checking integrity constraint integrity test