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Prediction of permeability from well logs using a new hybrid machine learning algorithm

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Petroleum 2023年第1期9卷 108-123页

作者： Morteza Matinkia Romina Hashami Mohammad Mehrad Mohammad Reza Hajsaeedi Arian velayati Department of Petroleum Engineering Omidiyeh BranchIslamic Azad UniversityOmidiyehIran Department of Applied Mathematics Faculty of Mathematics and Computer SciencesAmirkabir University of TechnologyTehranIran Faculty of Mining Petroleum and Geophysics EngineeringShahrood University of TechnologyShahroodIran Department of Chemical and Materials Engineering University of AlbertaEdmontonCanada

Permeability is a measure of fluid transmissibility in the rock and is a crucial concept in the evaluation of formations and the production of hydrocarbon from the *** techniques such as intelligent methods have been introduced to estimate the permeability from other petrophysical *** efficiency and convergence issues associated with artificial neural networks have motivated researchers to use hybrid techniques for the optimization of the networks,where the artificial neural network is combined with heuristic *** research combines social ski-driver(SSD)algorithm with the multilayer perception(MLP)neural network and presents a new hybrid algorithm to predict the value of rock *** performance of this novel technique is compared with two previously used hybrid methods(genetic algorithm-MLP and particle swarm optimization-MLP)to examine the effectiveness of these hybrid methods in predicting the permeability of the *** results indicate that the hybrid models can predict rock permeability with excellent ***-SSD method yields the highest coefficient of determination(0.9928)among all other methods in predicting the permeability values of the test data set,followed by MLP-PSO and MLP-GA,***,the MLP-GA converged faster than the other two methods and is computationally less expensive.

关键词： Permeability Artificial neural network Multilayer perceptron Social ski driver algorithm

Numerical investigation of the hydraulic fracturing mechanisms in oil sands

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Underground Space 2021年第2期6卷 195-216页

作者： Siavash Taghipoor Morteza Roostaei Arian velayati Atena Sharbatian Dave Chan Alireza Nouri Department of Civil and Environmental Engineering University of AlbertaCanada KGHM International 1010 Lorne StSudburyON P3C 4R9Canada RGL Reservoir Management Inc. 690842 StLeducAB T9E 0R8Canada

This paper presents a numerical investigation of hydraulic fracturing in oil sands during cold water injection by considering the aspects of both geomechanics and reservoir fluid *** to previous studies,the low shear strengths of unconsolidated or weakly consolidated sandstone reservoirs significantly influence the hydraulic fracturing ***,classical hydraulic fracture models cannot simulate the fracturing process in weak sandstone *** the current numerical models,the direction of a tensile fracture is predetermined based on in situ stress ***,the potential transformation of a shear fracture into a tensile fracture and the potential reorientation of a tensile fracture owing to shear banding at the fracture tip have not yet been addressed in the *** this study,a smeared fracture technique is employed to simulate tensile and shear fractures in oil *** model used combines many important fracture features,which include the matrix flow,poroelasticity and plasticity modeling,saturation-dependent permeability,gradual degradation of the oil sands as a result of dilative shear deformation,and the tensile fracturing and shear failure that occur with the simultaneous enhancement of ***,sensitivity analyses are also performed with respect to the reservoir and geomechanical parameters,including the apparent tensile strength and cohesion of the oil sands,magnitude of the minimum and maximum principal stress,absolute permeability and elastic modulus of the oil sands and ramp-up *** these analyses are performed to clarify the influences of these parameters on the fracturing response of the oil sands.

关键词： Smeared fracture Hydraulic fracturing Numerical simulation Oil sand

Prevalence of non-tuberculosis mycobacteria among samples deposited from the National Tuberculous Reference Laboratory of Iran(2011-2018)

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Asian Pacific Journal of Tropical Medicine 2021年第10期14卷 451-456页

作者： Saman Ayoubi Parissa Farnia Poopak Farnia Jafar Aghajani Jalaledin Ghanavi Ali Akbar velayati Mycobacteriology Research Center(MRC) National Research Institute of Tuberculosis and Lung Disease(NRITLD)Shahid Beheshti University of Medical SciencesTehranIran Department of Biotechnology School of Advanced Technology in MedicineShahid Beheshti University of Medical SciencesTehranIran

Objective:To investigate the prevalence of non-tuberculosis mycobacteria(NTM)among the samples deposited from the National Tuberculosis Reference Laboratory of Iran between 2011 and ***:The study evaluated the prevalence of NTM among specimens from patients with pulmonary tuberculosis symptoms(n=15771)deposited at the National Tuberculosis Reference Laboratory of Iran from 2011 to *** of Mycobacterium(M.)tuberculosis was based on presence of a 190-bp amplicon from IS6110 insertion sequence using Tb1 and Tb2 primers,and amplicon-negative specimens were tested for NTM and ***(refractory to IS6110 amplification)using restriction fragment length polymorphism PCR of hsp65 amplicon ***:A total of 7307(46.33%)*** and 658(4.17%)NTM specimens were found,the latter mainly comprising ***(10.18%),***(2.28%),***(8.97%),***(10.49%),***(4.71%),and ***(56.08%).Conclusions:As treatment for NTM differs from that for ***,accurate detection of Mycobacterium *** of public health significance.

关键词： Diagnosis Iran Non-tuberculosis Mycobacterium Prevalence

Colloidal gas aphron(CGA) based foam cement system

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Petroleum Exploration and Development 2019年第6期46卷 1281-1287页

作者： velayati Arian ROOSTAEI Morteza RASOOLIMANESH Rasool SOLEYMANI Mohammad FATTAHPOUR Vahidoddin University of Alberta Edmonton T6G 2R3Canada RGL Reservoir Management Inc. Leduc T9E 0B7Canada Supervisor of Design and Exploitation Unit at Ehyasepahan Iron Mines(EIM) Tehran ***Iran Drilling Technologies Director RIPITehran ***Iran

To solve the problems such as high denstiy,foam instability,low compressive strength,high porosity and poor durability associated with conventional foam cements,a novel colloidal gas aphron(CGA)based foam cement system was investigated and tested for *** is used in a base slurry as the foam component and the recipe was optimized with hollow sphere and micro-silica in terms of particle size distribution(PSD).Porosity,permeability,strength,brittleness,elasticity,free water content,foam stability and density tests on the CGA based foam cement system were carried out to evaluate the performance of the *** to the experiment results,at the foam proportion of 10%,the cement density was reduced to 1040 kg/m3,and stable microfoam net structure not significantly affected by high temperature and high pressure was formed in the cement *** optimal CGA based foam cement has a free water content of 0%,porosity of 24%,permeability of 0.7×10-3μm2,low elasticity modulus,high Poisson’s ratio,and reasonable compressive strength,and is more elastic and flexible with capability to tolerate regional stresses.

关键词： colloidal gas aphron foam cement light weight cement compressive strength well cementing

Comparison of resin composite restorations microleakage: An <i>in-vitro</i>study

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Open Journal of Stomatology 2013年第2期3卷 209-214页

作者： Horieh Moosavi Fatemeh Maleknejad Yazdi Fatemeh velayati Moghadam Saherh Soltani Dental Material Research Center and Operative Dentistry Department Dental School Mashhad University of Medical Sciences Mashhad Iran Dentist Mashhad Iran

The aim of this study was to compare the microleakage of total-etch and self-etch adhesives by three methods including dye extraction, dye penetration and fluid filtration with determining the correlation value among these techniques. Seventy-two premolar teeth were selected for this in vitro study and Class 5 cavities were prepared on the buccal surface of these at the cementoenamel junction area. It was applied for half of these cavities, Optibond Solo Plus (OSP) (two-step etch & rinse) and another half, Optibond All-in-One (OA) (one-step self-etch) and then all of them were restored with a light cure resin composite;Herculite XRV. Then samples were divided randomly into three subgroups based on the method of microleakage measurement (n = 12). In the first pair group, leakage was assessed by the dye extraction method. Dye penetration and fluid filtration methods were used in the second and third pair groups for the same purpose respectively. Data were analyzed by Paired t-test and Wilcoxon test and correlation coefficients (α = 0.05). There was no significant difference in the dye extraction (P = 0.657) and dye penetration (P = 0.732) methods between the microleakage of total-etch and self-etch adhesives. Microleakage of self-etch adhesive in fluid filtration technique was significantly more than total-etch adhesive (P = 0.012). No significant correlation was found among the results obtained with the three methods of microleakage evaluation. Adhesive systems showed variously behave in different methods of microleakage assessment.

关键词： Dye Extraction Dye Penetration Fluid Filtration Microleakage

Stool-based DNA testing,a new noninvasive method for colorectal cancer screening,the first report from Iran

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World Journal of Gastroenterology 2007年第10期13卷 1528-1533页

作者： Mohammad Reza Abbaszadegan Alireza Tavasoli Arash velayati Hamid Reza Sima Hassan Vosooghinia Mehdi Farzadnia Hamid Asadzedeh Mehran Gholamin Ezzat Dadkhah Azadeh Aarabi Mohammad Reza Abbaszadegan Division of Human GeneticsImmunology Research CenterBu-Ali Research InstituteMUMSMashhadIran Department of Surgery Ghaem HospitalMashhad University of Medical SciencesMashhadIran Department of Internal Medicine Imam Reza HospitalMUMSMashhadIran Department of Internal Medicine Ghaem HospitalMUMSMashhadIran Department of Pathology Imam Reza HospitalMUMSMashhadIran

AIM： To detect tumor-associated DNA changes in stool samples among Iranian patients with colorectal cancer （CRC） compared to healthy individuals using BAT-26, p16 hypermethylation and long DNA markers. METHODS： Stool DNA was isolated from 45 subjects including 25 CRC patients and 20 healthy individuals using a new, fast and easy extraction method. Long DNA associated with tumor was detected using polymerase chain reaction method. Microsatellite studies were performed utilizing denaturating polyacrylamide gel to determine the instability of BAT-26. Methylation status of p16 promoter was analyzed using methylation-specific PCR （MSP）. RESULTS： The results showed a significant difference in existence of long DNA （16 in patients vs 1 in controls, P 〈 0.001） and p16 （5 in patients vs none in controls, P = 0.043） in the stool samples of two groups. Long DNA was detected in 64% of CRC patients; whereas just one of the healthy individuals was positive for Long DNA. p16 methylation was found in 20% of patients and in none of healthy individuals. Instability of BATo26 was not detected in any of stool samples. CONCLUSION： We could detect colorectal cancer related genetic alterations by analyzing stool DNA with a sensitivity of 64% and 20% and a specificity of 95% and 100% for Long DNA and p16 respectively. A non- invasive molecular stool-based DNA testing can provide a screening strategy in high-risk individuals. However, additional testing on more samples is necessary from Iranian subjects to determine the exact specificity and sensitivity of these markers.

关键词： Stool DNA Colorectal cancer Cancer screening Long DNA BAT-26 p16