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High-resolution photogrammetry to measure physical aperture of two separated rock fracture surfaces

Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2922-2934页

作者： Masoud Torkan Mateusz Janiszewski Lauri Uotinen alireza baghbanan Mikael Rinne Department of Civil Engineering Aalto UniversityEspooFinland Department of Mining Engineering Isfahan University of TechnologyIsfahanIran

Photogrammetry,reconstructing three-dimensional(3D)models from overlapping two-dimensional(2D)photos,finds application in rock mechanics and rock engineering to extract geometrical details of reconstructed objects,for example rock *** properties are important for determining the mechanical stability,permeability,strength,and shear behavior of the rock *** can be used to reconstruct detailed 3D models of two separated rock fracture surfaces to characterize fracture roughness and physical aperture,which controls the fluid flow,hydromechanical and shear behavior of the rock *** research aimed to determine the optimal number of scale bars required to produce high-precision 3D models of a fracture surface.A workflow has been developed to define the physical aperture of a fracture using *** blocks of Kuru granite(25 cm×25 cm×10 cm)with an artificially induced fracture,were *** scaling 3D models,321 markers were used as ground control points(GCPs)with predefined distances on each *** the samples were wellmatched in their original positions,the entire block was *** data of the GCPs were extracted from the 3D model of the *** half was surveyed separately and georeferenced by GCPs and merged into the same coordinate *** fracture surfaces were extracted from the 3D models and the vertical distance between the two surfaces was digitally calculated as physical *** assessment of the photogrammetric reconstruction showed a 20-30 mm digital control distance accuracy when compared to known distances defined between *** attain this accuracy,the study found that at least 200 scale bars were ***,photogrammetry was employed to measure changes in aperture under normal *** results obtained from this approach were found to be in good agreement with those obtained using linear variable displacement transducers(LVDTs),with differences ran

关键词： Photogrammetry Physical aperture Rock fracture Predefined distances Markers

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Safety analysis of Sormeh underground mine to improve sublevel stoping stability

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Deep Underground Science and Engineering 2023年第2期2卷 173-187页

作者： Mostafa Hosseini Amin Azhari Rahman Lotfi alireza baghbanan Department of Mining Engineering Isfahan University of TechnologyIsfahanIran

In underground mines,sublevel stoping is used among a variety of different methods for mining an orebody,which creates large underground *** this case,the stability of these openings is affected by a number of factors,including the geometrical characteristics of the rock and mining-induced *** this study,a sensitivity analysis was conducted with the numerical,squat pillar,and Mathews stability methods using the Taguchi technique to properly understand the influence of geometric parameters and stress on stope stability according to Sormeh underground mine *** results show a full factorial analysis is more reliable since stope stability is a complex ***,the numerical results indicate that overburden stress has the most impact on stope stability,followed by stope ***,the results obtained with Mathews and squat pillar methods show that stope height has the greatest impact,followed by overburden stress and *** appears that these methods overestimate the impact of stope ***,it is highly recommended that Mathews and squat pillar methods should not be used in high stope that is divided with several sill ***,Mathews method cannot accurately predict how the sill pillar impacts the stope *** addition,numerical analysis shows that all geometric parameters affect the roof safety factor,whereas the sill pillar has no significant influence on the safety factor of the hanging wall,which is primarily determined by the stope height–span ratio.

关键词： numerical method rib pillar stope stability sublevel stoping underground mining

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Effect of seismic waves on the hydro-mechanical properties of fractured rock masses

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 525-536页

作者： Meysam Lak alireza baghbanan Hamid Hashemolhoseini Department of Mining Engineering Isfahan University of Technology (IUT) Isfahan Iran Department of Civil Engineering Isfahan University of Technology (IUT) Isfahan Iran

The transmission of seismic waves in a particular region may influence the hydraulic properties of a rock mass, including permeability, which is one of the most important. To determine the effect of a seismic wave on the hydraulic behavior of a fractured rock mass, systematic numerical modeling was conducted. A number of discrete fracture network（DFN） models with a size of 20 m × 20 m were used as geometrical bases, and a discrete element method（DEM） was employed as a numerical simulation tool. Three different boundary conditions without（Type Ⅰ） and with static（Type Ⅱ） and dynamic（Type Ⅲ） loading were performed on the models, and then their permeability was calculated. The results showed that permeability in Type Ⅲ models was respectively 62.7% and 44.2% higher than in Type I and Type Ⅱ models. This study indicates that seismic waves can affect deep earth, and, according to the results, seismic waves increase the permeability and change the flow rate patterns in a fractured rock mass.

关键词： wave transmission earthquake dynamic analysis discrete fracture network permeability UDEC

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An analytical model for estimating rock strength parameters from small-scale drilling data

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 135-145页

作者： Sajjad Kalantari alireza baghbanan Hamid Hashemalhosseini Department of Mining Engineering Isfahan University of Technology

The small-scale drilling technique can be a fast and reliable method to estimate rock strength parameters. It needs to link the operational drilling parameters and strength properties of rock. The parameters such as bit geometry, bit movement, contact frictions and crushed zone affect the estimated *** analytical model considering operational drilling data and effective parameters can be used for these purposes. In this research, an analytical model was developed based on limit equilibrium of forces in a Tshaped drag bit considering the effective parameters such as bit geometry, crushed zone and contact frictions in drilling process. Based on the model, a method was used to estimate rock strength parameters such as cohesion, internal friction angle and uniaxial compressive strength of different rock types from operational drilling data. Some drilling tests were conducted by a portable and powerful drilling machine which was developed for this work. The obtained results for strength properties of different rock types from the drilling experiments based on the proposed model are in good agreement with the results of standard tests. Experimental results show that the contact friction between the cutting face and rock is close to that between bit end wearing face and rock due to the same bit material. In this case,the strength parameters, especially internal friction angle and cohesion, are estimated only by using a blunt bit drilling data and the bit bluntness does not affect the estimated results.

关键词： Analytical model Rock strength parameters Small-scale drilling data

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Static and dynamic analysis on slope stability using a DFN-DEM approach on the right abutment of the Karun 4 dam

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Earthquake Engineering and Engineering Vibration 2020年第4期19卷 937-951页

作者： Sadegh Kefayati alireza baghbanan Masoud Torkan Hamid Hashemolhosseini Roohollah Narimani Dehnavi Department of Mining Engineering(DME) Isfahan University of Technology(IUT)Isfahan 84156-83111Iran Department of Civil Engineering(DCE) Isfahan University of Technology(IUT)Isfahan 84156-83111Iran

Uncertainty in input fracture geometric parameters during analysis of the stability of jointed rock slopes is inevitable and therefore the stochastic discrete fracture network(DFN)-distinct element method(DEM) is an efficient modeling tool. In this research, potentially unstable conditions are detected in the right abutment of the Karun 4 dam and downstream of the dam body as a case study. Two extreme states with small and relatively large block sizes are selected and a series of numerical DEM models are generated using a number of validated DFN models. Stability of the rock slope is assessed in both static and dynamic loading states. Based on the design basis earthquake(DBE) and maximum credible earthquake(MCE) expected in the dam site, histories of seismic waves are applied to analyze the stability of the slope in dynamic earthquake conditions. The results indicate that a MCE is likely to trigger sliding of rock blocks on the rock slope major joint. Furthermore, the dynamic analysis also shows a local block failure by the DBE, which can consequently lead to slope instability over the long term. According to the seismic behavior of the two models, larger blocks are prone to greater instability and are less safe against earthquakes.

关键词： rock slope DFN DEM UDEC dynamic behavior earthquake

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Tidal modeling based on satellite altimetry observations of TOPEX/ Poseidon, Jason1, Jason2, and Jason3 with high prediction capability: A case study of the Baltic Sea

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Geodesy and Geodynamics 2024年第4期15卷 404-418页

作者： alireza A.Ardalan Asiyeh Hashemifaraz School of Surveying and Geospatial Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal *** generate a time series of along-track observations and apply a developed method to produce tidal models with specific tidal constituents for each *** tidal modeling methodology follows an iterative process:partitioning sea surface height(SSH)observations into analysis/training and prediction/validation parts and ultimately identi-fying the set of tidal constituents that provide the best predictions at each time series *** study focuses on developing 1256 time series along the altimetry tracks over the Baltic Sea,each with its own set of tidal *** of the developed tidal models against the sSH observations within the prediction/validation part reveals mean absolute error(MAE)values ranging from 0.0334 m to 0.1349 m,with an average MAE of 0.089 *** same validation process is conducted on the FES2014 and EOT20 global tidal models,demonstrating that our tidal model,referred to as BT23(short for Baltic Tide 2023),outperforms both models with an average MAE improvement of 0.0417 m and 0.0346 m,*** addition to providing details on the development of the time series and the tidal modeling procedure,we offer the 1256 along-track time series and their associated tidal models as supplementary *** encourage the satellite altimetry community to utilize these resources for further research and applications.

关键词： Satellitealtimetry Baltic Sea Ocean tide modeling Jason3 Jason2 Jason1 TOPEX/Poseidon EOT20 FES2014

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Prevalence of Anemia in Patients with Diabetes Mellitus:A Systematic Review and Meta-Analysis

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Biomedical and Environmental Sciences 2024年第1期37卷 96-107页

作者： Monireh Faghir-Ganji Narjes Abdolmohammadi Maryam Nikbina alireza Amanollahi alireza Ansari-Moghaddam Rozhan Khezri Hamidreza Baradaran Student Research Committee Iran University of Medical SciencesTehranIran Department of Epidemiology School of Public HealthIran University of Medical SciencesTehranIran Department of Epidemiology School of Public HealthTehran University of Medical SciencesTehranIran Department of Midwifery Shoushtar Faculty of Medical SciencesShoushtarIran Department of Epidemiology School of Public Health and SafetyShahid Beheshti University of Medical SciencesTehranIran Trauma and Injury Research Center Iran University of Medical SciencesTehranIran Health Promotion Research Center Zahedan University of Medical SciencesZahedanIran Endocrine Research Center Institute of Endocrinology and MetabolismIran University of Medical SciencesTehranIran

Objective Anemia is a common public health concern in patients with type 2 diabetes *** study aimed to identify the prevalence of anemia among patients with *** Electronic databases,including PubMed,Scopus,Web of Sciences,and Google Scholar,were searched systematically for studies published between 2010 and *** removing duplicates and inappropriate reports,the remaining manuscripts were reviewed and appraised using theNewcastleOttawa Scale(NOS)tool.A random-effects model was used to calculate the pooled estimates of the extracted data using Stata version *** of the studies was assessed using the Q *** A total of 51 articles containing information on 26,485 patients with diabetes were included in this *** articles were mainly from Asia(58.82%)and Africa(35.29%).The overall prevalence of anemia was 35.45%(95%CI:30.30–40.76),with no evidence of heterogeneity by *** the two continents with the highest number of studies,the prevalence of anemia in patients with diabetes was significantly higher in Asia[40.02;95%CI:32.72–47.54]compared to Africa[28.46;95%CI:21.90–35.50](P for heterogeneity=0.029).Moreover,there has been an increasing trend in the prevalence of anemia in patients with diabetes over time,from[15.28;95%CI:9.83–22.21]in 2012 to[40.70;95%CI:10.21–75.93]in *** Globally,approximately 4 in 10 patients with diabetes suffer from ***,routine anemia screening and control programs every 3 months might be useful in improving the quality of life of these patients.

关键词： Prevalence Diabetic foot Anemia Diabetes mellitus

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Distributed Energy and Reserve Scheduling in Local Energy Communities Using L-BFGS Optimization

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 942-952页

作者： Mohammad Dolatabadi alireza Zakariazadeh Alberto Borghetti Pierluigi Siano Department of Management&Innovation Systems University of SalernoSalernoItaly Department of Electrical Electronicand Information EngineeringUniversity of BolognaBolognaItaly University of Science and Technology of Mazandaran BehshahrIran Department of Power Systems National University of Science and Technology POLITEHNICA BucharestBucharestRomania IEEE

Encouraging citizens to invest in small-scale renewable resources is crucial for transitioning towards a sustainable and clean energy *** energy communities(LECs)are expected to play a vital role in this ***,energy scheduling in LECs presents various challenges,including the preservation of customer privacy,adherence to distribution network constraints,and the management of computational *** paper introduces a novel approach for energy scheduling in renewable-based LECs using a decentralized optimization *** proposed approach uses the Limitedmemory Broyden–Fletcher–Goldfarb–Shanno(L-BFGS)method,significantly reducing the computational effort required for solving the mixed integer programming(MIP)*** incorporates network constraints,evaluates energy losses,and enables community participants to provide ancillary services like a regulation reserve to the grid *** assess its robustness and efficiency,the proposed approach is tested on an 84-bus radial distribution *** indicate that the proposed distributed approach not only matches the accuracy of the corresponding centralized model but also exhibits scalability and preserves participant privacy.

关键词： Distributed optimization flexibility services L-BFGS method local energy community renewables reserve

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Massive Dirac particles based on gapped graphene with Rosen-Morse potential in a uniform magnetic field

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Chinese Physics B 2024年第8期33卷 170-178页

作者： A.Kalani alireza Amani M.A.Ramzanpour Department of Physics Ayatollah Amoli BranchIslamic Azad UniversityAmolIran

We explore the gapped graphene structure in the two-dimensional plane in the presence of the Rosen-Morse potential and an external uniform magnetic *** order to describe the corresponding structure,we consider the propagation of electrons in graphene as relativistic fermion quasi-particles,and analyze it by the wave functions of two-component spinors with pseudo-spin symmetry using the Dirac ***,to solve and analyze the Dirac equation,we obtain the eigenvalues and eigenvectors using the Legendre differential *** that,we obtain the bounded states of energy depending on the coefficients of Rosen-Morse and magnetic potentials in terms of quantum numbers of principal n and spin-orbit ***,the values of the energy spectrum for the ground state and the first excited state are calculated,and the wave functions and the corresponding probabilities are plotted in terms of coordinates *** what follows,we explore the band structure of gapped graphene by the modified dispersion relation and write it in terms of the two-dimensional wave vectors K_(x) and K_(y).Finally,the energy bands are plotted in terms of the wave vectors K_(x) and K_(y) with and without the magnetic term.

关键词： massive Dirac equation Rosen–Morse potential Legendre polynomial gapped graphene pseudospin symmetry

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Synergistic effect of adsorption and photocatalytic degradation of oilfield-produced water by electrospun photocatalytic fibers of Polystyrene/Nanorod-Graphitic carbon nitride

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Journal of Environmental Sciences 2024年第7期141卷 287-303页

作者： Parisa Azmoon Mehrdad Farhadian alireza Pendashteh Amir H.Navarchian Department of Chemical Engineering Faculty of EngineeringUniversity of IsfahanIsfahanIran Department of Chemical Engineering Faculty of EngineeringUniversity of GuilanRashtIran Department of Water and Environmental Engineering Caspian Sea Basin Research CenterUniversity of GuilanRashtIran

Graphitic carbon nitride with nanorod structure(Nr-GCN)was synthesized using melamine as a precursor without any other reagents by hydrothermal pretreatment ***,FTIR,SEM,N_(2)adsorption-desorption from BET,UV-Vis DRS spectroscopy,and photoluminescence were used to characterize the prepared ***,the photoelectrochemical behavior of nanoparticles was studied by photocurrent transient response and cyclic voltammetry ***(PS)fibrous mat was fabricated by electrospinning technique and used as a support for the stabilization of the *** performance of the synthesized nanoparticles and photocatalytic fibers(PS/Nr-GCN)was evaluated in oilfield-produced water treatment under visible light *** this process,oil contaminants were adsorbed by hydrophobic polystyrene fibers and simultaneously degraded by *** removal efficiency of chemical oxygen demand(COD)has been obtained 96.6%and 98.4%by Nr-GCN and PS/Nr-GCN,respectively,at the optimum conditions of pH4,photocatalyst dosage 0.5 g/L,COD initial concentration 550 mg/L,and illumination time 150 *** gas chromatography-mass spectroscopy analysis results showed 99.3%removal of total petroleum hydrocarbons using photocatalytic fibers of PS/*** results demonstrated that the GCN has outstanding features like controllable morphology,visible-light-driven,and showing high potential in oily wastewater ***,the synergistic effect of adsorption and photocatalytic degradation is an effective technique in oilfield-produced water treatment.

关键词： Graphitic carbon nitride(GCN) Nanorod structure Polystyrene fibrous mat Photocatalytic fibers Oilfield-produced water(OPW)

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