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Calculation of a Three-Jet Cross Section via the e^(+)e^(−)→Hadronic Rindler Horizon→qqg Process

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Chinese Physics Letters 2013年第2期30卷 54-56页

作者： Ali reza Sepehri Somayyeh Shoorvazi Faculty of Physics Shahid Bahonar UniversityP.O.Box 76175KermanIran Islamic Azad University Neyshabur BranchNeyshaburIran

The cross section for three-jet events via the e^(+)e^(−)→hadronic Rindler horizon→qqg process is compared to experimental data from the OPAL *** is found that the model is consistent with the QCD experiments.

关键词： ler experiments. hadron

Production optimization in a fractured carbonate reservoir with high producing GOR

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 224-239页

作者： Amin Izadpanahi reza Azin Shahriar Osfouri reza Malakooti Escola Politécnica Universidade de São PauloBrazil Department of Petroleum Engineering Faculty of Petroleum Gas&Petrochemical EngineeringPersian Gulf UniversityBushehrIran Department of Chemical Engineering Faculty of Petroleum Gas&Petrochemical EngineeringPersian Gulf UniversityBushehrIran Computer Modelling Group LondonUK

The Gas-Oil Ratio(GOR)is a crucial production parameter in oil *** increase in GOR results in higher gas production and lower oil production,potentially leading to well shut-ins due to economic *** study focuses on a real fractured oil field that requires urgent production operations to reduce the producing *** this study,the static model for the field was developed using commercial software,involving steps such as data collection,fault modeling,meshing,and statistical analysis to prepare for dynamic *** dynamic model incorporates geometry,gridding,and rock properties from the static model,utilizing a dual-porosity approach for the naturally fractured reservoir and the Peng-Robinson equation for fluid phase *** reservoir conditions,production history,and rock-fluid interactions were defined,with relative permeability curves indicating a water-wet reservoir and low critical gas saturation affecting the *** better understand the relationship between reservoir and production parameters,a detailed sensitivity analysis was performed using the Response Surface Methodology(RSM).Following the sensitivity analysis,a history matching process was conducted using the Designed Exploration and Controlled Evolution(DECE)optimizer to validate the model for future *** operational scenarios were defined to decrease the production GOR and enhance final recovery from the *** results indicate that the water injection scenario is effective in preventing the GOR increase by maintaining reservoir pressure,thereby sustaining production over a longer *** scenario also improves oil recovery by approximately 6%compared to the base ***,optimization was carried out using the DECE optimizer for each scenario to fine-tune the operational *** goal was to maximize oil revenue for each scenario during the optimization *** study stands out as one of the few that provides a comprehensive analysis

关键词： Reservoir simulation Sensitivity analysis Response surface methodology High gas-oil ratio Production optimization

FREE VIBRATION ANALYSIS OF SIMPLY SUPPORTED BEAM WITH BREATHING CRACK USING PERTURBATION METHOD

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Acta Mechanica Solida Sinica 2010年第5期23卷 459-470页

作者： Mousa rezaee reza Hassannejad Department of Mechanical Engineering University of Tabriz

In this paper, a new analytical method for vibration analysis of a cracked simply supported beam is investigated. By considering a nonlinear model for the fatigue crack, the governing equation of motion of the cracked beam is solved using perturbation method. The solution of the governing equation reveals the superhaxmonics of the fundamental frequency due to the nonlinear effects in the dynamic response of the cracked beam. Furthermore, considering such a solution, an explicit expression is also derived for the system damping changes due to the changes in the crack parameters, geometric dimensions and mechanical properties of the cracked beam. The results show that an increase in the crack severity and approaching the crack location to the middle of the beam increase the system damping. In order to validate the results, changes in the fundamental frequency ratios against the fatigue crack severities are compared with those of experimental results available in the literature. Also, a comparison is made between the free response of the cracked beam with a given crack depth and location obtained by the proposed analytical solution and that of the numerical method. The results of the proposed method agree with the experimental and numerical results.

关键词： free vibration cracked beam breathing crack damping factor perturbation method

How do machine learning techniques help in increasing accuracy of landslide susceptibility maps?

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Geoscience Frontiers 2020年第3期11卷 871-883页

作者： Yacine Achour Hamid reza Pourghasemi Department of Civil Engineering Bordj Bou Arreridj University34030El AnnasserAlgeria Department of Natural Resources and Environmental Engineering College of AgricultureShiraz UniversityShirazIran

Landslides are abundant in mountainous *** are responsible for substantial damages and losses in those *** A1 Highway,which is an important road in Algeria,was sometimes constructed in mountainous and/or semi-mountainous *** studies of landslide susceptibility mapping conducted near this road using statistical and expert methods have yielded ordinary *** this research,we are interested in how do machine learning techniques help in increasing accuracy of landslide susceptibility maps in the vicinity of the A1 Highway *** do this,an important section at Ain Bouziane(NE,Algeria) is chosen as a case study to evaluate the landslide susceptibility using three different machine learning methods,namely,random forest(RF),support vector machine(SVM),and boosted regression tree(BRT).First,an inventory map and nine input factors were prepared for landslide susceptibility mapping(LSM) *** three models were constructed to find the most susceptible areas to this *** results were assessed by calculating the receiver operating characteristic(ROC) curve,the standard error(***),and the confidence interval(CI) at 95%.The RF model reached the highest predictive accuracy(AUC=97.2%) comparatively to the other *** outcomes of this research proved that the obtained machine learning models had the ability to predict future landslide locations in this important road *** addition,their application gives an improvement of the accuracy of LSMs near the road *** machine learning models may become an important prediction tool that will identify landslide alleviation actions.

关键词： Spatial modelling Support vector machine Random forest Boosted regression tree Validation measures Algeria

Combined load bearing capacity of rigid piles embedded in a crossanisotropic clay deposit using 3D finite element lower bound

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 717-737页

作者： Ardavan Izadi reza Jamshidi Chenari Department of Civil Engineering Faculty of EngineeringUniversity of GuilanRashtGuilanIran

In this study,an iterative-based three-dimensional finite element lower bound in association with the second-order cone programming method is adopted to evaluate the limit load of a single pile embedded in cross-anisotropic soils under general loading *** lower bound solutions of the pile embedded in an anisotropic soil deposit can be found by formulating the element equilibrium,equilibrium of shear and normal stresses along discontinuities,boundary conditions,yield function,and optimizing the objective function through the second-order cone programming method in conjunction with an iterative-based update procedure.A general loading condition is considered to profile the expansion of the safe load in the vertical-horizontal-moment(V-H-M)*** results of this study are compared and validated against three different cases including an isotropic lateral loading,anisotropic end bearing capacity,and a pile embedded in an isotropic soil deposit under general loading condition.A parametric study is conducted to evaluate the impact of different influencing *** was found that the effect of anisotropy on the variation of lateral limit load of a single pile is more pronounced than the corresponding vertical and bending moment limit loads,whereas the interface properties have more significant effects on the vertical and bending moment limit loads in comparison to the lateral limit load.

关键词： Rigid pile Cross-anisotropy Clay Combined loading Three-dimensional finite element lower bound

CHARACTEIZATIONS OF WOVENT g-FRAMES AND WEAVING g-FRAMES IN HILBERT SPACESS AND C^(*)-MODULES

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维普期刊数据库

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Acta Mathematica Scientia 2023年第6期43卷 2471-2482页

作者： Amir KHOSRAVI Mohammad reza FARMANI Faculty of Mathematical Sciences and Computer Kharazmi University599 Taleghani Ave.Tehran 15618Iran

In this paper,using Parseval frames we generalize Sun’s results to g-frames in Hilbert C^(*)-***,for g-frames in Hilbert spaces,we present some characterizations in terms of a family of frames,not only for orthonormal ***,we have a note about a comment and a relation in the proof of Proposition 5.3 in[*** et al.,On weaving g-frames for Hilbert spaces,Complex Analysis and Operator Theory,2020].Finally,we have some results for g-Riesz bases,woven and P-woven g-frames.

关键词： g-frame fusion frame woven frame Riesz basis g-Riesz basis

Effect of Active Gas on Weld Shape and Microstructure of Advanced A-TIG-Welded Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2016年第3期29卷 295-300页

作者： reza Nakhaei Alireza Khodabandeh Hamidreza Najafi Department of Materials Engineering Tehran Science and Research BranchIslamic Azad University

Advanced A-TIG method was conducted to increase the weld penetration and compared with the conventional TIG welding process.A two-pipeline setup was designed to apply Ar ＋ CO_2 mixed gas as the outer layer,while pure argon was applied as the inner layer to prevent any consumption of the tungsten *** results indicate that the presence of active gas in the molten pool led to the change in the temperature coefficient of surface tension so that the Marangoni convection turns inward and forms a deep weld *** increase in gas flow rate causes a decrease in the weld efficiency which is attributed to the increase in oxygen content in the weld pool and the formation o f a thicker oxide layer on the weld ***,the stir and the temperature fluctuation,led by double shielding gas,create more homogeneous nucleation sites in the molten pool so that a fine grain micros true ture was obtained.

关键词： Advanced A-TIG welding Weld metal Active gas Microstructure Marangoni convection

Influences of adsorptions of some inorganic molecules on electronic, optical, and thermodynamic properties of Mg_(12)O_(12) nanocage: A computational approach

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Chinese Physics B 2018年第8期27卷 280-289页

作者： Asghar Mohammadi Hesari Hamid reza Shamlouei Chemistry Department Lorestan UniversityI(horram AbadLorestanIraa

According to density functional theory, we investigate the effects of BF3, BF4, BCI3, A1F3, AICI3, A1Br3, 13eF3, GaF3, GaC13, GaBr3, NO3, BS2, BSO, BO2, F2, PFs, PC15, and ASF5 molecules on the geometric, electronic, linear, and nonlinear optical properties of an Mg12012 nanocage. The thermodynamic stability and feasibility of the adsorption process are investigated by analyzing the free energy. It is shown that the adsorptions of almost all molecules on the Mg12OI2 surface are exothermic. The calculations of the polarizability of these nanoclusters show that among the studied molecules, BeF3 has the largest influence on the polarizability value （a≈315 a.u., the unit a.u. is short for atomic unit）. The static first hyperpolarizability （β0） value is increased in the presence of these superhalogens. This increase is greatest for BeF3 and BF4 of which the highest value of the first hyperpolarizability （βO≈ 5775 a.u.） is related to a BeF3_c（e@Mgl2Ol2） nanocluster. The adsorption position is a key to estimating the value of increasing the first hyperpolarizability.

关键词： Mg1201 polarizability hyperpolarizability binding energy nanocage DFT calculation

Partially decoupling and collar bonding of the encapsulated rebar rockbolts to improve their performance in seismic prone deep underground excavations

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International Journal of Mining Science and Technology 2019年第3期29卷 409-418页

作者： reza Masoudi Mostafa Sharifzadeh Masoud Ghorbani Department of Mining & Metallurgical Engineering Curtin UniversityWestern Australian School of Mines (WASM)Australia Department of Mining Metallurgy and Petroleum EngineeringAmirkabir University of Technology (Tehran Polytechnic)TehranIran

Rockbolt is widely employed all over the world as an effective ground reinforcement element in order to secure the underground *** encapsulated rebar or rebar rockbolt is most popular and commonly used as reinforcement in a ground support system because of its accessibility,cost effectiveness and easy *** elements in a seismic condition such as rock burst have to dissipate the energy release of the dynamic impact via their deformation and ultimate load capacity,knowing that the former is more *** other words,achieving early stiff behaviour along with large deformation capacity in rockbolts are the goals for new development in rock *** rockbolts are expensive while some of them have large deformation capability with low ultimate load *** this paper,modifications were made on encapsulation of rebar rockbolts to utilise it effectively as a yielding reinforcement in seismic *** a sufficient decoupled length in the shank of rebar rockbolts which industry has regularly been using to control the bulking of the stress fractured ground,improves the deformation capacity of the ***,leaving a collar bonding underneath of the bearing pad and plate removes the weaknesses of the head anchorage of *** the dynamic performance of the bolt is improved by these easily applicable *** behaviour and performance of encapsulated rockbolts have been discussed first,then the effects of modifications are *** proposed modification of the rebars is not only cost effective but also easy to apply in the field and improves the performance of reinforcements in seismic prone zones.

关键词： Rockbolt Tunnel support Collar bonding Seismic rock support Tunnelling