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Bearing capacity of circular footings on multi-layered sand-waste tire shreds reinforced with geogrids

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1085-1094页

作者： mahmoud Ghazavi Ehsan Khosroshahi Faculty of Civil Engineering K.N.Toosi University of TechnologyTehranIran

The presence of waste tires poses an environmental challenge as they occupy a significant amount of land and are expensive to dispose in ***,reusing waste tires can address this issue when waste tires are used in geotechnical *** determine the viability of this approach,laboratoryscale tests were conducted to investigate load-bearing capacity of circular footings on sand-tire shred(STS)mixtures with shredded waste tire contents of 5%e15%by weight and three different widths of *** investigation focused on analyzing the thickness of layers composed of STS mixtures,the soil cap,and the impact of geogrids on bearing *** results indicate that a specific mixture of sand and tire shreds provides the highest footing-bearing *** addition,the optimal shred content and size were found to be 10%by weight and 2 cm×10 cm,***,for a given tire shred width,a particular length provides the largest bearing *** results agree well with that of previous research conducted by the first author and his colleagues in direct shear and California bearing ratio(CBR)*** primary finding of this research is that the use of two-layered STS mixtures reinforced by geogrids significantly enhances the bearing capacity.

关键词： Geogrid Sand Waste tire shred Bearing capacity Waste tire shred optimization Tire shred aspect ratio

Design of a Bio-inspired Hull Shape for an AUV from Hydrodynamic Stability Point of View through Experiment and Numerical Analysis

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Journal of Bionic Engineering 2018年第6期15卷 950-959页

作者： Amir Honaryar mahmoud Ghiasi Faculty of Marine Technology Amirkabir University of Technology Hafez Avenue 15875-4413 Tehran Iran

The hydrodynamic characteristics and body shape of catfish, Hypostomus, are used to design and develop an Autonomous Under- water Vehicle （AUV） named ZRAUV for subsea pipeline and cable inspection. Among the hydrodynamic characteristics, stability of this bio-inspired AUV, which may be adversely affected by disturbances such as marine currents during inspection process, is taken into consideration and evaluated both numerically and experimentally. Concerning numerical investigation, computational fluid dynamics based on Reynolds Averaged Navier-Stokes equations are applied to compute the hydrodynamic damping derivatives needed for stability analysis. In order to verify the numerical predictions, computations are also performed for the well-known submarine body with a typical axisymmetric hull shape, SUBOFF. Experiments are also carried out for both proposed AUV and a conventional axisymmetric one using self-propulsion tests. Measurements of turning rate in turning circle maneuver are in reasonably good agreement with those of numerical estimations and indicate that the turning rate of conventional bodies like SUBOFF is approximately 3.8 times as great as that of bio-inspired AUV. In other words, the findings reveal that in comparison with common axisymmetric bodies, the proposed AUV with biological hull shape is more stable by about 99%, thus, it is highly suitable for subsea pipeline and cable inspection.

关键词： catfish hydrodynamic stability bio-inspired AUV hull form computational fluid dynamics

Dielectric spectroscopy coupled with artificial neural network for classification and quantification of sesame oil adulteration

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Information Processing in Agriculture 2022年第2期9卷 233-242页

作者： mahmoud Soltani Firouz mahmoud Omid Mehrdad Babaei Mahdi Rashvand Department of Agricultural Machinery Engineering Faculty of Agricultural Engineering and TechnologyUniversity of TehranKarajIran Machine Design and Mechatronics Department Institute of MechanicsIranian Research Organization for Science and TechnologyTehranIran

Adulteration using cheap vegetable oils into expensive oils such as sesame oil is a considerable challenge in the edible oil market. To discriminate pure and adulterated sesame oilwith sunflower and canola oils (commonly used as an adulterant to the high-price oils),dielectric spectroscopy was applied in the range of 40 kHz–20 MHz. The principal component analysis (PCA) plots were able to distinguish the pure sesame oil, while it was impossible to separate the adulterated oils based on the kind of adulteration. The correlationbased feature selection (CFS) method was used to select the more relevant dielectric datawithin the spectrum and to reduce the dimensionality of the input vector belongs to theartificial neural network (ANN). The ANN classifier with topology of 19-5-4 structureshowed a perfect accuracy of 100% in detecting the authentic and the adulterated sesameoil. The regression ANN with the topology of 15-5-1, 21-8-1 and 10-11-1 were the mostrobust models in quantifying the amount of adulteration in sesame oil generated by sun-flower oil, canola oil and sunflower + canola oils, with R2Test of 1, 1 and 0.999 9, *** proposed technique is a powerful and simple method to detect and quantify adulteration of sesame oil. The novelty of this research is capability of used system for authentication of adulterated sesame oil using low frequency. Furthermore, the developed systemhas a good capability for other types of sesame oil adulterations as well as to detect adulteration in other expensive edible oils.

关键词： Adulteration Artificial neural network Chemometrics Sesame oil Correlation-based feature selection Principal component analysis

Arabic Bank Check Processing: State of the Art

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Journal of Computer Science & Technology 2013年第2期28卷 285-299页

作者： Irfan Ahmad Sabri A.mahmoud Information and Computer Science Department King Fahd University of Petroleum & Minerals

In this paper, we present a general model for Arabic bank check processing indicating the major phases of a check processing system. We then survey the available databases for Arabic bank check processing research. The state of the art in the different phases of Arabic bank check processing is surveyed （i.e., pre-processing, check analysis and segmentation, features extraction, and legal and courtesy amounts recognition）. The open issues for future research are stated and areas that need improvements are presented. To the best of our knowledge, it is the first survey of Arabic bank check processing.

关键词： handwriting analysis document analysis text processing feature evaluation and selection pattern analysis

Source localization based on field signatures:Laboratory ultrasonic validation

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Journal of Electronic Science and Technology 2024年第3期22卷 47-56页

作者： mahmoud Eissa Dmitry Sukhanov Department of Radiophysics Tomsk State UniversityTomsk634050Russia Higher Institute for Applied Sciences and Technology(HIAST) Damascus31983Syria

Location awareness in wireless networks is essential for emergency services,navigation,gaming,and many other *** article presents a method for source localization based on measuring the amplitude-phase distribution of the field at the base *** existing scatterers in the target area create unique scattered field interference at each source *** unique field interference at each source location results in a unique field signature at the base station which is used for source *** the proposed method,the target area is divided into a grid with a step of less than half the *** grid node is characterized by its field signature at the base *** signatures corresponding to all nodes are normalized and stored in the base station as fingerprints for source *** normalization of the field signatures avoids the need for time synchronization between the base station and the *** a source transmits signals,the generated field signature at the base station is normalized and then correlated with the stored *** maximum correlation value is given by the node to which the source is the *** simulations and results of experiments on ultrasonic waves in the air show that the ultrasonic source is correctly localized using broadband field signatures with one base station and without time *** proposed method is potentially applicable for indoor localization and navigation of mobile robots.

关键词： Base station Field signature Fingerprints Localization Ultrasonic frequencies

Aerodynamic Characteristics of Conventional and Innovative High Lift Swept Wings

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Journal of Bionic Engineering 2019年第3期16卷 432-441页

作者： Mojtaba Ramezani Voloojerdi mahmoud Mani Aerospace Engineering Department Amirkabir University of Technology 424 Hafez Ave Tehran 158757413 Iran

The new bird inspired wing sweep was introduced and compared with straight and conventional swept wings in gliding flight by an experimental test setup. Due to the similarity with the birds, wing, all test models have S1223 airfoil. Swept models inspired from the bird consist of two parts: the straight part near the root and the swept part near the tip. Aerodynamic forces on each wing were measured from 0° to 24° angles of attack and Reynolds numbers of 4.3×10^4, 8.6×10^4, 1.3×10^5, and 1.7× 10^5. Wind tunnel test results show that wings with an innovative sweep at α> 0 have more lift for Reynolds numbers between 4.3× 10^4 and 8.6×10^4. Also, innovative sweep increases the stall angle, and the wing did not stall until α = 24° for Reynolds between 1.3×10^5 and 1.7×10^5. An increase in lift and having sufficient aerodynamic performance in low Reynolds numbers for birds' inspired wing sweep in gliding flight may be the answer to why the wing sweep of birds is not like conventional sweeps.

关键词： bio-inspired wing wing sweep wing aerodynamics bird wing low Reynolds number

Nonlinear dynamics of two degree of freedom systems with linear and nonlinear stiffnesses

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Earthquake Engineering and Engineering Vibration 2013年第3期12卷 411-420页

作者： Bayat mahmoud I.Pakar Department of Civil Engineering Mashhad Branch Islamic Azad UniversityMashhad Iran

In this study, a new analytical approach is developed to analyze the free nonlinear vibration of conservative two-degree-of-freedom （TDOF） systems. The mathematical models of these systems are governed by second--order nonlinear partial differential equations. Nonlinear differential equations were transferred into a single equation by using some intermediate variables. The single nonlinear differential equations are solved by using the first order of the Hamiltonian approach （HA）. Different parameters, which have a significant impact on the response of the systems, are considered and discussed. Some comparisons are presented to verify the results between the Hamiltonian approach and the exact solution. The maximum relative error is less than 2.2124 % for large amplitudes of vibration. It has been established that the first iteration of the Hamiltonian approach achieves very accurate results, does not require any small perturbations, and can be used for a wide range of nonlinear problems.

关键词： nonlinear vibration two-degree-of-freedom (TDOF) analytical approach Hamitonian approach (HA)

Changes in Relative Plate Motion during the Isan Orogeny(1670-1500Ma) and Implications for Pre-Rodinia Reconstructions

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Acta Geologica Sinica(English Edition) 2016年第1期90卷 88-105页

作者： A.S.A.A.abu SHARIB School of Earth and Environmental Science James Cook University Geology Department Beni-Suef University

Foliation inflexion/intersection axes （FIAs） preserved within porphyroblasts that grew throughout Isan orogenesis reveal significant anticlockwise changes in the direction of bulk horizontal shortening between 1670 and 1500 Ma from NE-SW, N-S, E-W to NW-SE. This implies an anticlockwise shift in relative plate motion with time during the Isan orogeny. Dating monazite grains amongst the axial planar foliations defining three of the four FIAs enabled an age for the periods of relative plate motion that produced these structures to be determined. Averaging the ages from monazite grains defining each FIA set revealed 1649^-12 Ma for NE-SW shortening, 1645±7 Ma for N-S shortening, and 1591±10 Ma for that directed E-W. Inclusion trail asymmetries indicate shear senses of top to the SW for NW-SE FIAs and dominantly top to the N for E-W FIAs, reflecting thrusting towards the SW and N. No evidence for tectonism related to early NE-SW bulk horizontal shortening has previously been detected in the Mount Isa Inlier. Amalgamation of the Broken Hill and possibly the Gawler provinces with the Mount Isa province may have taken place during these periods of NE-SW and N-S-directed thrusting as the ages of tectonism are similar. Overlapping dates, tectonic, metamorphic, and metallogenic similarities between eastern Australia （Mount Isa and Broken Hill terranes） and the southwest part of Laurentia imply a most probable connection between both continental masses. Putting Australia in such position with respect to North America during the Late-Paleo-to-Mesoproterozoic time is consistent with the AUSWUS model of the Rodinia supercontinent.

关键词： Foliation Intersection/Inflexion Axes (FIA) tectono-metamorphic porphyroblasts bulk horizontal shortening Isan Orogeny.

Analysing user daylight preferences in heritage buildings using virtual reality

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Building Simulation 2022年第9期15卷 1561-1576页

作者： Mohamed Marzouk Maryam ElSharkawy Ayman mahmoud Department of Structural Engineering Faculty of EngineeringCairo University12613GizaEgypt Department of Architecture Engineering Faculty of EngineeringCairo University12613GizaEgypt

Technology has always been creating effective ways to support human *** virtual reality(IVR)has emerged to engage users in a simulated world,and this has gained the interest of a wide variety of users in the heritage industry.A historical case study built in the early 19th century is considered for an adaptive reuse *** palace is located in Cairo,Egypt,and named after Prince Omar *** current palace state incorporates a smashed top-lit zone,which is being studied and analyzed for daylighting *** simulated distinct optimum skylight configurations are suggested for the redesign where the selection should not be based solely on simulation data,but should consider real-user *** daylight design criteria are previously based on simulation data that do not necessarily indicate the users'*** utilizing user interactive tools such as IVR to test daylight redesign options,a whole new dimension is *** this study,the VR users’survey data is statistically analyzed using Statistical Package for Social Sciences(SPSS),where results revealed that the assessment attributes succeeded in reflecting the users'preferences;which,motivated designers to consider potential users’daylight preferences in reused *** paper highlights the most significant emotional attributes that provide cost-effective and reliable information concerned with the performance of daylight in IVR before design *** study compares and analyzes the effect of three skylight designs(Cases A,B&C)on the users'perception before design implementation using(IVR)***-eight participants have contributed to the study,providing their feedback on six attributes namely:Pleasant,Contrasting,Brightness,Uniform Distribution,Visual Comfort,and *** attributes are evaluated for the three cases in space using five scale rating values to reveal that the"Pleasant"attribute is most reliable in the study to reflect th

关键词： daylight preferences heritage buildings rehabilitation immersive virtual reality statistical analysis