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A new robust predictive model for lost circulation rate using convolutional neural network:A case study from Marun Oilfield

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Petroleum 2023年第3期9卷 468-485页

作者： Farshad Jafarizadeh Babak Larki Bamdad Kazemi Mohammad Mehrad sina rashidi Jalil Ghavidel Neycharan Mehdi Gandomgoun Mohammad Hossein Gandomgoun Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Department of Petroleum Engineering Omidiyeh Branch of Islamic Azad UniversityOmidiyehIran Science and Research Branch Islamic Azad UniversityTehranIran Faculty of Mining Petroleum and Geophysics EngineeringShahrood University of TechnologyShahroodIran Department of Information Technology and Computer Engineering Shahid Madani University of AzerbaijanTabrizIran Faculty of Petroleum Engineering Sahand University of TechnologyTabrizIran

A major cause of some of serious issues encountered in a drilling project,including wellbore instability,formation damage,and drilling string stuck e which are known to increase non-productive time(NPT)and hence the drilling cost e is what we know as mud *** mud loss can be prevented or at least significantly reduced by taking proper measures beforehand provided the position and intensity of such loss can be properly predicted using an accurate predictor ***,in this study,we used the convolutional neural network(CNN)and hybridized forms of multilayer extreme learning machine(MELM)and least square support vector machine(LSSVM)with the Cuckoo optimization algorithm(COA),particle swarm optimization(PSO),and genetic algorithm(GA)for modeling the mud loss rate based on drilling data,mud properties,and geological information of 305 drilling wells penetrating the Marun *** this purpose,we began by a pre-processing step to attenuate the effect of noise using the Savitzky-Golay *** whole set of available data was divided into the modeling(including 2300 data points)and the validation(including 483 data points)***,the second generation of the non-dominated sorting genetic algorithm(NSGA-Ⅱ)was applied to the modeling data to identify the most significant features for estimating the mud *** results showed that the prediction accuracy increased with the number of selected features,but the increase became negligible when the number of selected features exceeded ***,the following 9 features were selected as input to the intelligent algorithms(IAs):pump pressure,mud weight,fracture pressure,pore pressure,depth,gel 10 min/gel 10 s,fan 600/fan 300,flowrate,and formation *** of the hybrid algorithms and simple forms of LSSVM and CNN to the training data(80%of the modeling data,i.e.1840 data points)showed that all of the models tend to underestimate the mud loss at higher mud loss rates,although the CNN exhibited l

关键词： Lost circulation prediction Artificial intelligence Deep learning Feature selection

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Predictor homotopy analysis method for nanofluid flow through expanding or contracting gaps with permeable walls

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International Journal of Biomathematics 2015年第4期8卷 145-159页

作者： Navid Freidoonimehr Behnam Rostami Mohammad Mehdi rashidi Young Researchers and Elite Club Hamedan Branch Islamic Azad University Hamedan Iran Shanghai Key Lab of Vehicle Aerodynamics and Vehicle Thermal Management Systems4800 Cao An Rd. Jiadong Shanghai 201804 P. R. China ENN-Tongji Clean Energy Institute of Advanced Studies Shanghai P. R. China Mechanical Engineering DepartmentEngineering Faculty of Bu-Ali sina University Hamedan Iran

In this paper a definitely new analytical technique, predictor homotopy analysis method (PHAM), is employed to solve the problem of two-dimensional nanofluid flow through expanding or contracting gaps with permeable walls. Moreover, comparison of the PHAM results with numerical results obtained by the shooting method coupled with a Runge–Kutta integration method as well as previously published study results demonstrates high accuracy for this technique. The fluid in the channel is water containing different nanoparticles: silver, copper, copper oxide, titanium oxide, and aluminum oxide. The effects of the nanoparticle volume fraction, Reynolds number, wall expansion ratio, and different types of nanoparticles on the flow are discussed.

关键词：流体流动问题纳米颗粒同伦分析预测器水墙差距龙格-库塔积分方法

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Comparative numerical study of single and two-phase models of nanofluid heat transfer in wavy channel

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Applied Mathematics and Mechanics(English Edition) 2014年第7期35卷 831-848页

作者： M.M.rashidi A.HOSSEINI I.POP S.KUMAR N.FREIDOONIMEHR Department of Mechanical Engineering Faculty of EngineeringBu-Ali Sina UniversityHamedan 65178-38695 Iran Department of Mathematics Babe?Bolyai UniversityCluj-Napoca 400084Romania Department of Mathematics National Institute of TechnologyJamshedpur 831014Jharkhand India Young Researchers & Elite Club Hamedan BranchIslamic Azad UniversityHamedan 65181-15743 Iran

The main purpose of this study is to survey numerically comparison of two- phase and single phase of heat transfer and flow field of copper-water nanofluid in a wavy channel. The computational fluid dynamics （CFD） prediction is used for heat transfer and flow prediction of the single phase and three different two-phase models （mixture, volume of fluid （VOF）, and Eulerian）. The heat transfer coefficient, temperature, and velocity distributions are investigated. The results show that the differences between the temperature fie].d in the single phase and two-phase models are greater than those in the hydrodynamic tleld. Also, it is found that the heat transfer coefficient predicted by the single phase model is enhanced by increasing the volume fraction of nanoparticles for all Reynolds numbers; while for the two-phase models, when the Reynolds number is low, increasing the volume fraction of nanoparticles will enhance the heat transfer coefficient in the front and the middle of the wavy channel, but gradually decrease along the wavy channel.

关键词： nanofluid two-phase model wavy channel semi implicit method for pres-sure linked equation (SIMPLE) method

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Effects of thermal boundary conditions on the joule heating of electrolyte in a microchannel

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Journal of Hydrodynamics 2016年第5期28卷 850-862页

作者： M. Y. ABDOLLAHZADEH JAMALABADI J. H. PARK M. M. rashidi J. M. CHEN Department of Ship Engineering Chabahar Maritime University Chabahar Iran Department of Aerospace and System Engineering Gyeongsang National University Jinju Korea . Engineering Faculty of Bu-Ali sina University Hamedan Iran Department of Mechanical and Nuclear Engineering Kansas State University Manhattan USA

Joule heating effects on a slit microcharmel filled with electrolytes are comprehensively investigated with emphasis on the thermal boundary conditions. An accurate analytical expression is proposed for the electrical field and the temperature distributions due to Joule heating are numerically obtained from the energy balance equation. The results show that a thermal design based on the average electric potential difference between electrodes can cause severe underestimation of Joule heating. In addition, the parame- tric study of thermal boundary conditions gives us an insight into the best cooling scenario for microfluidic devices. Other significant thermal characteristics, including Nusselt number, thermophoretic force, and entropy generation, are discussed as well. This study will provide useful information for the optimization of a bioMEMS device in relation to the thermal aspect.

关键词： microchannel electrolyte joule heating Nusselt number thermophoretic force entropy generation optimized thermaldesign

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A numerical study for off-centered stagnation flow towards a rotating disc

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Propulsion and Power Research 2015年第3期4卷 169-178页

作者： M.Heydari G.B.Loghmani M.M.rashidi S.M.Hosseini Department of Mathematics Yazd UniversityP.O.Box 89195-741YazdIran Mechanical Engineering Department Engineering Faculty of Bu-Ali Sina UniversityHamedanIran Department of Mathematics Khatam CenterIslamic Azad UniversityYazdIran

In this investigation,a semi-numerical method based on Bernstein polynomials for solving off-centered stagnation flow towards a rotating disc is *** method expands the desired solutions in terms of a set of Bernstein polynomials over a closed interval and then makes use of the tau method to determine the expansion coefficients to construct approximate *** method can satisfy boundary conditions at *** properties of Bernstein polynomials are presented and are utilized to reduce the solution of governing nonlinear equations and their associated boundary conditions to the solution of algebraic *** results are presented to investigate the influence of the rotation ratioαon the radial velocity,azimuthal velocity and the induced velocities.A comparative study with the previous results of viscous fluid flow in the literature is made.

关键词： Off-centered stagnation flow Similarity transform Bernstein polynomials Function approximation Tau method

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Pressure ulcers and acute risk factors in individuals with traumatic spinal fractures with or without spinal cord injuries:A prospective analysis of the National Spinal Column/Cord Injury Registry of Iran(NSCIR-IR)data

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Chinese Journal of Traumatology 2023年第4期26卷 193-198页

作者： Farzin Farahbakhsh Hossein Rezaei Aliabadi Vali Baigi Zahra Ghodsi Mohammad Dashtkoohi Ahmad Pour-Rashid James SHarrop Vafa Rahimi-Movaghar sina and Trauma Surgery Research Center Tehran University of Medical SciencesTehranIran Brain and SpinalCord Injury Research Center NeuroscienceInstute Tehran Universityof Medical SciencesTehranIran Department of Neurosurgery Shariati HospitalTehran University of Medical SciencesTehranIran Sports Medicine Research Center Tehran University of Medical SciencesTehranIran School of Medicine Bam University of Medical SciencesBamIran Students'Scientific Research Center(SSRC) Tehran University of Medical SciencesTehranIran Department of Neurosurgery Sina HospitalTehran University of Medical SciencesTehranIran Department of Neurosurgery Thomas Jefferson UniversityPhiladelphiaUSA Universal Scientific Education and Research Network(USERN) TehranIran Institute of Biochemistry and Biophysics University of TehranTehranIran Spine Program University of TorontoTorontoCanada

Purpose:To identify risk factors for developing pressure ulcers(PUs)in the acute care period of traumatic spinal fracture patients with or without spinal cord injuries(SCIs).Methods:Data were collected prospectively in participating the National Spinal column/Cord Injury Registry of Iran(NSCIR-IR)from individuals with traumatic spinal fractures with or without SCIs,in-clusive of the hospital stay from admission to *** nursing staff examined the patients for the presence of PUs every 8 h during their hospital *** presence and grade of PUs were assessed according to the European Pressure Ulcer Advisory Panel *** addition to PU,following data were also extracted from the NSCIR-IR datasets during the period of 2015-2021:age,sex,Glasgow coma scale score at admission,having SCIs,marital status,surgery for a spinal fracture,American Spinal Injury Association impairment scale(AIS),urinary incontinence,level of education,admitted center,length of stay in the intensive care unit(ICU),hypertension,respiratory diseases,consumption of ciga-rettes,diabetes mellitus and length of stay in the *** regression models were used to es-timate the unadjusted and adjusted odds ratio(OR)with 95%confidence intervals(CI).Results:Altogether 2785 participants with traumatic spinal fractures were *** them,87(3.1%)developed PU during their hospital stay and 392(14.1%)had *** the SCI population,63(16.1%)developed PU during hospital *** logistic regression for the whole sample showed that marital status,having SCIs,urinary incontinence,level of education,treating center,number of days in the ICU,age,and Glasgow coma scale score were significant predictors for ***,further analysis by multiple logistic regression only revealed the significant risk factors to be the treating center,marital status,having SCIs,and the number of days in the *** the subgroup of individuals with SCIs,marital status,AIS,urinary incontinenc

关键词： Spinal fractures Spinal cord injuries Pressureulcer NSCIR-IR

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Synthesis,characterization,in vitro antimicrobial and antioxidant activities of catecholthioethers

Synthesis,characterization,in vitro antimicrobial and antiox...

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13th Asian Chemical Congress

作者： ADIBI HADI KHODAEI MOHAMMAD MEHDI ALIZADEH ABDOLHAMID PAKRAVAN NARGES rashidi ATEFEH MAJNOONI MOHAMMAD BAGHER ABIRI RAMIN NEMATOLLAHI DAVOOD Faculty of Pharmacy Kermanshah University of Medical SciencesKermanshahIran Faculty of of Chemistry Razi University Faculty of Medicine Kermanshah University of Medical SciencesKermanshahIran Faculty of Chemistry Bu-Ali Sina University

＜正＞Generation of reactive oxygen species（ROS）and free radicals in vivo is involved in a wide range of human ***,including superoxide anion,hydrogen peroxide and hydroxyl radical,are by products of a variety of pathways of aerobic *** catecholthioethers have become an important structural motif in biological *** report here the synthesis of a series of

关键词： Catecholthioethers Antioxidant Antimicrobial

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