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Estimation of highway capacity under environmental constraints *** traffic flow criteria:A case study of Tehran

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第5期8卷 751-761页

作者： Hamid Mirzahossein Farshid Safari erfan Hassannayebi Department of Civil Engineering-Transportation Faculty of Technical and EngineeringImam Khomeini International University(IKIU)Qazvin 34148-96818Iran Research Centre for Integrated Transport Innovation(rCITI) School of Civil and Environmental EngineeringUniversity of New South WalesSydneyNSW 2052Australia Department of Industrial Engineering Sharif University of TechnologyTehran 14588-89694Iran

In this paper,the concept of environmental capacity is developed to identify a convenient maximum traffic volume which will not reduce the life quality of *** presented method investigates the idea of traffic capacity under environmental constraints by calculating the maximum number of vehicles allowed on roads based on acceptable levels of air and noise *** this study,the permissible noise pollution level and permissible levels of CO and NOxpollution are considered for determining environmental *** show the significant difference between environmental capacity and functional traffic capacity,introduced by the highway capacity manual(HCM)as a conventional method for estimating functional ***,maximum allowed pollution is considered a constraint on a vehicle flow rate,which shows the proper traffic flow for selected streets in Tehran,Iran’s *** paper concludes that traffic capacity under noise and air pollution constraints is much less(approximately one-fourth and one-eighth for noise and air pollution respectively)than the current highway capacity estimated using HCM ***,to save the cities like Tehran from noise and air pollution,traffic flows should be limited to the level of environmental capacity by implementing some travel demand management(TDM)policies like road pricing.

关键词： Traffic engineering Environmental pollutions Environmental capacity estimation Admissible traffic flow Highway capacity manual(HCM)

Processing of nanostructured metallic matrix composites by a modified accumulative roll bonding method with structural and mechanical considerations

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 951-956页

作者： Amir Hossein Yaghtin erfan Salahinejad Ali Khosravifard Department of Materials Science and Engineering(Shiraz Branch) Islamic Azad UniversityShiraz 71955Iran Department of Materials Science and Engineering School of EngineeringShiraz UniversityShiraz ***Iran

Particulate reinforced metallic matrix composites have attracted considerable attention due to their lightweight, high strength, high specific modulus, and good wear resistance. A1/B4C composite strips were produced in this work by a modified accumulative roll bonding process where the strips were rotated 90° around the normal direction between successive passes. Transmission electron microscopy and X-ray diffraction analyses reveal the development of nanostructures in the Al matrix after seven passes. It is found that the B4C reinforcement distribution in the matrix is improved by progression of the process. Additionally, the tensile yield strength and elongation of the processed materials are increased with the increase of passes.

关键词： metallic matrix composites particle reinforced composites nanostructures aluminum boron carbide roll bonding tensile properties

Evaluating the characteristics of geological structures in karst groundwater inflow, Nowsud Tunnel

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Journal of Mountain Science 2024年第10期21卷 3434-3452页

作者： BAYAT Narges SADEGHI erfan NASSERY Hamid Reza Department of Minerals and Groundwater Resources Faculty of Earth SciencesShahid Beheshti UniversityEvin AveTehran ***Iran Ministry of Energy Kordestan ExpyTehran ***Iran

Highly permeable geological structures such as dissolution channels, open fractures, and faults create environmental challenges regard to hydrological and hydrogeological aspects of underground construction, often causing significant groundwater inflow during drilling due to the limitations of empirical and analytical methods. This study aims to identify the geological factors influencing water flow into the tunnel. High-flow zones' geological features have been identified and examined for this purpose. According to the geological complexity of the Nowsud tunnel, presence of different formations with different permeability and karstification have led to a high volume of underground inflow water (up to 4700 L/s) to the tunnel. The Nowsud tunnel faces significant geological and hydrogeological challenges due to its passage through the Ilam formation's LI2 unit, characterized by dissolution channels, faults, and fractures. The highest inflow rate (4700 L/s) occurred in the Hz-9 zone within the Zimkan anticline. The relationship between geological features and groundwater inflow indicates that anticlines are more susceptible to inflow than synclines. Additionally, different types of faults exhibit varying hydraulic effects, with strike-slip faults having the most significant impact on groundwater inflow, thrust faults conducting less water into the tunnel, and inflow through normal faults being negligible compared to the other two types of faults. The novelty of this paper lies in its detailed analysis of geological features influencing groundwater inflow into the Nowsud tunnel, providing empirical data on high-flow zones and differentiating the hydraulic effects of various fault types, which enhances the understanding and prediction of groundwater inflow in underground constructions.

关键词： Geological structures Groundwater inflow Hydrogeology Nowsud tunnel Karst

Dynamic earth pressure on rigid retaining walls induced by a neighboring machine foundation,by the meshless local Petrov-Galerkin method

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Earthquake Engineering and Engineering Vibration 2015年第4期14卷 647-661页

作者： Mehdi Veiskarami Arash Bahar erfan Zandi Lak Geotechnical Engineering Division Department of Civil EngineeringUniversity of Guilan Department of Civil and Environmental Engineering School of Engineering No.1Shiraz University Structural Engineering Division Department of Civil EngineeringUniversity of Guilan

Dynamic earth pressure induced by machine foundations on a neighboring retaining wall is analyzed with emphasis on factors which control the intensity and location of the design forces. The meshless local Petrov-Galerkin (MLPG) method is used to analyze the problem for a variety of retaining wall and machine foundation geometries. The soil medium is assumed to be homogeneous and visco-elastic. The machine foundation is idealized as a harmonic sinusoidal dynamic force often encountered in practice. A number of analyses have been made to reveal the effect of the loading frequency, the location and size of the foundation and the soil shear wave velocity on the distribution and magnitude of the dynamic earth pressure. Results indicate that there is a critical frequency and a critical location for which the passive pressure takes the maxima in the entire duration of the dynamic load.

关键词： MLPG retaining wall dynamic loading visco-elastic soil machine foundation

Fabrication of Bulk (Fe,Cr)_3Al/Al_2O_3 Intermetallic Matrix Nanocomposite Through Mechanical Alloying and Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 911-919页

作者： Sayyed erfan Aghili Mohammad Hossein Enayati Fathallah Karimzadeh Department of Materials Engineering Isfahan University of Technology

In the present study, （Fe,Cr）3Al/20 vol% A1203 nanocomposite was prepared through mechanochemical reactions during ball milling and successfully bulked using a combination of cold isostatic press and sintering at 1400℃ for 1 h. Two processing approaches were utilized to produce （Fe,Cr）3A1/A1203 nanocomposite： The first was milling of Fe, Cr, AI and Fe203, while the second one was milling of Fe, Cr, Al and Cr203, both in stoichiometric condition, to synthesize （Fe,Cr）3Al/20 vol% Al2O3. Structural changes of powder particles during mechanical alloying were studied by X-ray diffraction. The microstructure and the morphology of powder particles and bulk samples were also studied by scanning electron microscopy and transmission electron microscopy. Microstructural analysis showed that mechanochemical reactions took place during milling, and nanometric Al2O3 was uniformly distributed in the matrix. The results also showed that the second approach required a considerably higher milling time to produce （Fe,Cr）3Al/Al2O3 nanocomposite, as compared to the first one. For this reason, bulk samples were produced from the synthesized nanocomposite in the first approach. The microstructure of the sintered samples consisted of a network structure of （Fe,Cr）3Al and Al2O3 phases with superior mechanical properties.

关键词： Iron aluminide Mechanical alloying Nanocomposite Mechanochemical treatment

Wettability modification effects on relative permeability end-points:Comparative analysis of surfactant agents for enhanced oil recovery

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Petroleum Research 2024年第2期9卷 206-218页

作者： erfan Hosseini Negar Hosseini Mohammad Sarmadivaleh Exploration Directorate National Iranian Oil Company(NIOC)TehranIran Department of Petroleum Engineering Islamic Azad University(IAU)IlamIran WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerthWestern AustraliaAustralia

This research examines the impact of wettability alteration on the end points of relative permeability,a crucial property of fluids and porous media that influences the displacement processes of immiscible fluids through such *** estimation of the mobility ratio for oil recovery relies on these end points,which are influenced by connate water saturation and residual oil *** investigate this relationship,carbonate rock is generally subjected to wettability alteration using surfactant agents,and core flooding is employed to determine the relative permeability before and after the *** wettability of the rock is commonly assessed through contact angle *** surfactants,TritonX-100(Tx-100)and Cedar,were tested in reducing the wettability of the porous media for *** contact angle measurements revealed that Tx-100 was more effective for this purpose than ***,the relative permeability tests indicated that both surfactants decreased residual oil saturation,but Tx-100 also improved system *** contrast,Cedar reduced residual oil saturation but increased system pressure,possibly because of its high *** results also demonstrate that injecting Tx-100 leads to a 14%increase in ultimate oil recovery compared with water injection,while Cedar injection increased the recovery factor by 5%.This difference may be attributed to the incomplete coverage of the pore wall by Cedar or its weaker chemical structure than ***,in carbonate cores,neither non-ionic surfactant enhanced oil recovery.

关键词： Wettability alteration Relative permeability Core flooding Tx-100 Cedar Contact angle

S100A4 in esophageal cancer:Is this the one to blame?

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World Journal of Gastroenterology 2012年第30期18卷 3931-3935页

作者： Jianyuan Chai M mazen Jamal Laboratory of GI Injury and Cancer VA Long Beach Healthcare System Long Beach CA 90822 United States Division of Gastroenterology Department of Medicine University of California Irvine CA 92868 United States

Metastasis is the main reason for cancer-related death.S100A4 is one of the key molecules involved in this *** studies have shown that overexpression of S100A4 in non-metastatic cancer cells can make them become metastatic,and knockdown of S100A4 in metastatic cancer cells can curtail their invasive nature.A study by Chen et al published in the World J Gastroenterol 18(9):915-922,2012 is a typical *** study showed in vitro and in vivo evidence that S100A4 expression level determines the invasiveness of esophageal squamous *** the fact that more than half of the cancer-related deaths are caused by malignancies derived from the digestive system and esophageal cancer is the 4th top contributor to this fraction,this study warrants more attention.

关键词： Esophageal cancer S100A4 Metastasis

Antioxidant potential of pentoxifylline on spermatozoa of small ruminants

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Asian pacific Journal of Reproduction 2022年第3期11卷 138-145页

作者： mazen Alomar Division of Animal Production Department of AgricultureAtomic Energy CommissionP.O.Box 6091DamascusSyria

Objective:To investigate antioxidant potential of pentoxifylline on spermatozoa of small ruminants including rams and ***:The levels of hydrogen peroxide(H2O2)production in ram and buck spermatozoa incubated with 0(control),4 and 8 mM of pentoxifylline were measured after 45-min ***,the motility parameters of ram and buck spermatozoa incubated with 0(control),1 mM of H2O2,1 mM of H2O2 plus 4 mM of pentoxifylline,and 1 mM of H2O2 plus 8 mM of pentoxifylline were analysed.H2O2 was estimated using a fluorometric assay and spermatozoa motility characteristics were analyzed using computer aided sperm ***:Pentoxifylline significantly decreased the levels of H2O2 produced from both ram and buck spermatozoa(P<0.05),and significant lower rates of H2O2 formation were noted when 8 mM of pentoxifylline was added(P<0.05).The values of all sperm motility parameters for the two species significantly decreased after incubation with H2O2(P<0.05).In contrast,when the spermatozoa were incubated with both H2O2 and two concentrations of pentoxifylline,the motility values rose significantly compared to those incubated with H2O2 alone(P<0.05).For both ram and buck sperm samples,the rapid and static subpopulation motility parameters were the most affected categories by pentoxifylline addition compared to the medium and slow ***:Pentoxifylline possesses an antioxidant capacity proved by its ability of reducing H2O2 levels as well as by increasing motility values of stressed ***,pentoxifylline could be recommended as antioxidant additive for spermatozoa of small ruminants under stress conditions.

关键词： Pentoxifylline Spermatozoa Ram Buck Motiltiy Hydrogen peroxide H2O2 Antioxidants

Computational Analysis of Novel Extended Lindley Progressively Censored Data

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2571-2596页

作者： Refah Alotaibi mazen Nassar Ahmed Elshahhat Department of Mathematical Sciences College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Statistics Faculty of ScienceKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Statistics Faculty of CommerceZagazig UniversityZagazigEgypt Faculty of Technology and Development Zagazig UniversityZagazig44519Egypt

A novel extended Lindley lifetime model that exhibits unimodal or decreasing density shapes as well as increasing,bathtub or unimodal-then-bathtub failure rates, named the Marshall-Olkin-Lindley (MOL) model is *** this research, using a progressive Type-II censored, various inferences of the MOL model parameters oflife are introduced. Utilizing the maximum likelihood method as a classical approach, the estimators of themodel parameters and various reliability measures are investigated. Against both symmetric and asymmetric lossfunctions, the Bayesian estimates are obtained using the Markov Chain Monte Carlo (MCMC) technique with theassumption of independent gamma priors. From the Fisher information data and the simulatedMarkovian chains,the approximate asymptotic interval and the highest posterior density interval, respectively, of each unknownparameter are calculated. Via an extensive simulated study, the usefulness of the various suggested strategies isassessedwith respect to some evaluationmetrics such as mean squared errors, mean relative absolute biases, averageconfidence lengths, and coverage percentages. Comparing the Bayesian estimations based on the asymmetric lossfunction to the traditional technique or the symmetric loss function-based Bayesian estimations, the analysisdemonstrates that asymmetric loss function-based Bayesian estimations are preferred. Finally, two data sets,representing vinyl chloride and repairable mechanical equipment items, have been investigated to support theapproaches proposed and show the superiority of the proposed model compared to the other fourteen lifetimemodels.

关键词： Marshall-Olkin-Lindleymodel reliability inference Bayesian and classical inference progressive Type-II censoring