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An analytical solution for spherical fluid flow modeling in porous media with non-uniform initial pressure considering the supercharging effect

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Petroleum 2021年第3期7卷 303-313页

作者： Ali Nabizadeh Mohammad sharifi Babak Aminshahidi Institute of GeoEnergy Engineering School of EnergyGeoscienceInfrastructure and SocietyHeriot-Watt UniversityEdinburghUK Department of Petroleum Engineering Amirkabir University of Technology(Tehran Polytechnic)P.O.Box:15875-4413TehranIran

The diffusivity equation is a partial differential equation(PDE)which can be used for fluid flow modeling in porous *** reservoir parameters from pressure data(i.e.,pressure transient analysis)is one of the most important steps in the process of field *** initial evaluation can be used to make decisions about future *** Formation Testing(WFT)is one of the most popular techniques for parameter estimation and has received significant attention in recent *** main problem plaguing WFT is a phenomenon known as the“supercharging effect,”which essentially refers to mud invasion,and this,in turn,alters pressure distribution across the *** this study,an analytical solution for fluid flow modeling in spherical coordinates with non-uniform initial pressure is *** new procedure takes into account the effect of mud invasion,or,in other words,the supercharging *** accuracy of this derivation was validated using previous semianalytical solutions(the Laplace method)in addition to field *** type curves and dimensionless parameters,which can be used for pressure transient analysis,are also *** procedure is applied to the WFT data that was obtained from an oil field in the south of Iran,and an excellent agreement(less than 10%error)was *** addition,there is considerable uncertainty regarding the radius of investigation for spherical *** is important as this parameter greatly affects the applicability of *** analytical derivation of this study was used to determine a reasonable value for this parameter as well.

关键词： Porous media Analytical solution Supercharging effect Welltesting Spherical Darcy's flow

Review on application of nanoparticles for EOR purposes: A critical review of the opportunities and challenges

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Chinese Journal of Chemical Engineering 2019年第2期27卷 237-246页

作者： Yousef Kazemzadeh Sanaz Shojaei Masoud Riazi Mohammad sharifi Department of Petroleum Engineering Amirkabir University of Technology Tehran Polytechnic Enhanced Oil Recovery (EOR) Research Centre IOR/EOR Research Institute Shiraz University Petroleum Engineering Department School of Chemical and Petroleum Eng. Shiraz University

Nanoparticles have already gained attentions for their countless potential applications in enhanced oil ***-sized particles would help to recover trapped oil by several mechanisms including interfacial tension reduction, impulsive emulsion formation and wettability alteration of porous media. The presence of dispersed nanoparticles in injected fluids would enhance the recovery process through their movement towards oil–water interface. This would cause the interfacial tension to be reduced. In this research, the effects of different types of nanoparticles and different nanoparticle concentrations on EOR processes were investigated. Different flooding experiments were investigated to reveal enhancing oil recovery mechanisms. The results showed that nanoparticles have the ability to reduce the IFT as well as contact angle, making the solid surface to more water wet. As nanoparticle concentration increases more trapped oil was produced mainly due to wettability alteration to water wet and IFT reduction. However, pore blockage was also observed due to adsorption of nanoparticles, a phenomenon which caused the injection pressure to increase. Nonetheless, such higher injection pressure could displace some trapped oil in the small pore channels out of the model. The investigated results gave a clear indication that the EOR potential of nanoparticle fluid is significant.

关键词： Enhance oil recovery Nanofluid injection Nanoparticle Interfacial tension Wettability alteration Pore blockage

Correlations between various rock mass classification/characterization systems for the Zagros tunnel-W Iran

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Journal of Mountain Science 2020年第7期17卷 1790-1806页

作者： Shahriar SADEGHI Ebrahim sharifi TESHNIZI Benyamin GHOREISHI Department of Geology Faculty of scienceImam Khomeini International UniversityQazvin34149-16818Iran Engineering Geology Young Researchers and Elite ClubShahrekord BranchIslamic Azad UniversityShahrekord15655-461Iran

This study deals with the comparative investigation on various classification/characterization systems for sedimentary rocks in two parts,40 kmlong of the Zagros tunnel,west of *** results of extensive geotechnical explorations and field measurements were applied to obtain the rock mass classification/characterization systems such as Rock Mass Rating(RMR),Rock Condition Rating(RCR),Q-system(Q),Rock Mass Number(QN),Rock Mass index(RMi),Rock Structure Rating(RSR),and Geological Strength Index(GSI)for a wide range of sedimentary rocks.A set of systems inter-relationship is *** of these correlation relations such as RMR-Q,RMR-RMi,RMi-Q,RCR,GSI-GSI(Cai)are similar to the one or more relations proposed in the previous studies,however,some of them such as RSR-RMR,RSR-Q,RCR-QN and GSI-RMR are not similar to the previous *** set orientation and joint set number are more important parameters that cause weak correlation coefficients where both side classifications are not similar in considering them in calculating *** it is proposed to find relations between any pairs of systems that both of them consider or not consider these *** relations are proposed for a wide range of sedimentary rocks and can be applied for similar geological environments.

关键词： Rock mass dassification/characterization systems Zagros Tunnel Sedimentaiy rocks

Assessment of Cu(Ⅱ) removal from an aqueous solution by raw Gundelia tournefortii as a new low-cost biosorbent: Experiments and modelling

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Chinese Journal of Chemical Engineering 2019年第8期27卷 1945-1955页

作者： Saba Golshan Shandi Faramarz Doulati Ardejani Fereydoun sharifi School of Mining College of EngineeringUniversity of TehranTehranIran Faculty of Mining Petroleum and GeophysicsShahrood University of TechnologyShahroodIran

Lignocellulosic materials can be used as biosorbent for refinement of the wastewaters when they are available in large quantities. Many studies were conducted to uptake Cu(Ⅱ) ion from aqueous *** this paper, the biosorption efficiency of Cu(Ⅱ) ions from a synthetic aqueous solution was investigated using Gundelia tournefortii(GT), without any pre-treatment. Fourier transform infrared spectroscopy,scanning electron microscopy and determining the point of zero charge were employed to characterise the biosorbent. Batch experiments were performed to study the influence of p H, biosorbent dosage, contact time, temperature and initial Cu(Ⅱ) concentration on Cu(Ⅱ) removal. The biosorption isotherms were investigated using the Langmuir, Freundlich, Temkin and D-R isotherm models. The findings show that the biosorption isotherm was better fitted by the Langmuir equation and the maximum adsorption capacity of GT was found to be 38.7597 mg·g^-1. The kinetics data were analysed by pseudo-first order,pseudo-second order, and intra-particle diffusion equations. The results indicate that the pseudosecond-order model was found to explain the adsorption kinetics most effectively. The values of thermodynamic parameters including Gibbs free energy(△G°), enthalpy(△H°), and entropy(△S°) demonstrate that the biosorption process was exothermic and spontaneous. The multiple nonlinear regression(MnLR)and artificial neural network(ANN) analyses were applied for the prediction of biosorption capacity. A relationship between the predicted and observed data was obtained and the results show that the Mn LR and ANN models provided successful predictions.

关键词： Adsorption Batch experiment Kinetics Isotherms Thermodynamic Multiple nonlinear regression Artificial neural network

Photometric stereo for strong specular highlights

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Computational Visual Media 2018年第1期4卷 83-102页

作者： Maryam Khanian Ali sharifi Boroujerdi Michael BreuB Chair of Applied Mathematics Brandenburg Universityof TechnologyCottbus 03046Germany

Photometric stereo is a fundamental technique in computer vision known to produce 3D shape with high accuracy. It uses several input images of a static scene taken from one and the same camera position but under varying illumination. The vast majority of studies in this 3D reconstruction method assume orthographic projection for the camera *** addition, they mainly use the Lambertian reflectance model as the way that light scatters at ***, providing reliable photometric stereo results from real world objects still remains a challenging task. We address 3D reconstruction by use of a more realistic set of assumptions, combining for the first time the complete Blinn–Phong reflectance model and perspective projection. Furthermore, we compare two different methods of incorporating the perspective projection into our model. Experiments are performed on both synthetic and real world images; the latter do not benefit from laboratory conditions. The results show the high potential of our method even for complex real world applications such as medical endoscopy images which may include many specular highlights.

关键词： photometric stereo(PS) complete Blinn–Phong model perspective projection diffuse reflection specular reflection

Gaussian orthogonal matrix transform approach for PAPR reduction of optical OFDM signals

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Optoelectronics Letters 2020年第3期16卷 216-219页

作者： Abbas Ali sharifi Ghanbar Azarnia Department of Electrical Engineering University of BonabBonab ***Iran Engineering Faculty of Khoy Urmia UniversityUrmiaIran

Optical orthogonal frequency division multiplexing(O-OFDM)has been widely adopted as a high-speed data transmission technique in visible light communication *** technique usually suffers from high peak-to-average-power ratio(PAPR).In this paper,a new PAPR reduction technique is proposed for O-OFDM *** the transmitter,a matrix transformation with the Gaussian elements is applied to the time-domain O-OFDM signal and at the receiver,the inverse matrix is used to recover the original *** show that the Gaussian orthogonal matrices can reconstruct the original signals without degrading the bit error rate(BER)***-Schmidt technique is used to orthogonalize the Gaussian *** simulations are conducted for 16-QAM baseband modulated symbols and about 3 dB PAPR reduction gain is achieved by the proposed approach compared with conventional O-OFDM.

关键词： matrix orthogonal Gaussian

Design and analysis of carbon nanotube FET based quaternary full adders

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Frontiers of Information Technology & Electronic Engineering 2016年第10期17卷 1056-1066页

作者： Mohammad Hossein MOAIYERI Shima SEDIGHIANI Fazel sharifi Keivan NAVI Faculty of Electrical Engineering Shahid Beheshti University Tehran *** Iran Nanotechnology and Quantum Computing Lab Shahid Beheshti University Tehran *** Iran

CMOS二进制逻辑受短沟道效应、功率密度及互连约束等条件的限制。非硅多值逻辑计算是克服上述问题的一种有效方案。本研究在碳纳米管场效应管(carbon nanotube field effect transistors,CNTFET)的基础上提出了两种高性能四进制全加单... 详细信息

CMOS二进制逻辑受短沟道效应、功率密度及互连约束等条件的限制。非硅多值逻辑计算是克服上述问题的一种有效方案。本研究在碳纳米管场效应管(carbon nanotube field effect transistors,CNTFET)的基础上提出了两种高性能四进制全加单元。该全加单元利用了CNTFET独有的特性,如目标电压阈值可通过调整碳纳米管管径控制、CNTFET具有与p型和n型器件相同的迁移性。通过在Synopsys HSPICE中使用32 nm斯坦福综合CNTFET模型,在多种测试条件下对所述电路单元进行了仿真。与当前水平的四进制全加器相比,本文所采用的设计平均降低延迟32%,所需平均功率、能耗及静态功率分别为现有水平的68%、83%及77%。仿真结果表明,所述设计在生产制程、电压、温度变化、噪声耐受方面具有较好的鲁棒性。

关键词：纳米电子碳纳米管场效应管多值逻辑四进制逻辑

Daily variation of urban heat island effect and its correlations to urban greenery： A case study of Adelaide

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Frontiers of Architectural Research 2017年第4期6卷 529-538页

作者： All Soitani Ehsan sharifi Shiraz University Shiraz Iran University of South Australia Australia University of Adelaide Australia

Urban structure and landscape cause an artificial temperature increase in cities, known as the urban heat island effect. The magnitude of such urban-rural temperature difference varies in daily and seasonal basis. Daily patterns of urban heat accumulation in Adelaide is under investigation. In this paper, East-West air temperature profile of Adelaide metropolitan area was mapped in 60 journeys alongside a straight cross route connecting Adelaide Hills to the West Beach under clear sky between 26 July and 15 August 2013. The most intense urban-rural temperature differences of 5.9 ℃ occurred during midnight in Adelaide. However, maximum urban heat variation occurred during the late afternoon when the near-surface urban heat fluctuates by 2 ℃ between the CBD East and Western Parklands. During summer heatwaves, the afternoon heat stress limits public life vibrancy in Adelaide. Increased urban greenery can facilitate resilience to heat by providing shadow and evaporative cooling. A better under- standing of daily urban heat variations and the cooling effect of urban greenery assists urban poticy making and public life management in the context of climate change.

关键词： Urban heat istandeffect Mobite traversemethod Heat stress Urban greenery Adetaide

Aging behavior of a copper-bearing high-strength low-carbon steel

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 429-438页

作者： Babak Shahriari Reza Vafaei Ehsan Mohammad sharifi Khosro Farmanesh Department of Materials Engineering Malek Ashtar University of Technology

The effects of aging temperature and time on the hardness and impact toughness of a copper-bearing high-strength low-carbon steel were investigated. The hardness of the aged samples reached maxima after 1 h and 5 h of aging at 500 and 450℃, respectively; this increase in hardness was followed by a decrease in hardness until a temperature of 700℃, at which secondary hardening was observed. The impact toughness of the aged steel was found to be higher for 5 h of aging. Transmission electron microscopy confirmed the presence of carbide and copper precipitates; also, the secondary hardening could be the result of the transformation of austenite（formed in the aging treatment） to martensite. Differential scanning calorimetry of the steel was performed to better understand the precipitation behavior. The results revealed that the precipitation of the steel exhibited two significant stages of copper precipitate nucleation and coarsening of the precipitates, with corresponding activation energies of 49 and 238 kJ·mol^-1, respectively.

关键词： aging treatment BA-160 steel differential scanning calorimetry precipitation