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Gain-scheduling control of a floating offshore wind turbine above rated wind speed

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Control Theory and Technology 2015年第2期13卷 160-172页

作者： omid BAGHERIEH Ryozo NAGAMUNE Department of Mechanical Engineering University of California at Berkeley 5146 Etcheverry Hall Department of Mechanical Engineering University of British Columbia 6250 Applied Science Lane

This paper presents an application of gain-scheduling(GS) control techniques to a floating offshore wind turbine on a barge platform for above rated wind speed cases. Special emphasis is placed on the dynamics variation of the wind turbine system caused by plant nonlinearity with respect to wind speed. The turbine system with the dynamics variation is represented by a linear parameter-varying(LPV) model, which is derived by interpolating linearized models at various operating wind speeds. To achieve control objectives of regulating power capture and minimizing platform motions, both linear quadratic regulator(LQR) GS and LPV GS controller design techniques are explored. The designed controllers are evaluated in simulations with the NREL 5 MW wind turbine model, and compared with the baseline proportional-integral(PI) GS controller and non-GS controllers. The simulation results demonstrate the performance superiority of LQR GS and LPV GS controllers, as well as the performance trade-off between power regulation and platform movement reduction.

关键词： Wind energy gain-scheduling control linear parameter-varying model floating offshore wind turbines above rated wind speed power

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

Experimental investigation on freeze-thaw durability of polymer concrete

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 1038-1046页

作者： Khashayar JAFARI Fatemeh HEIDARNEZHAD omid MOAMMER Majid JARRAH Department of Civil and Environmental Engineering Pennsylvania State UniversityUniversity ParkPA16802USA Department of Civil Engineering Sharif University of TechnologyTehranIran Department of Civil and Environmental Engineering Washington State UniversityPullmanWA99164USA

Assessing the durability of concrete is of prime importance to provide an adequate service life and reduce the repairing cost of ***-thaw is one such test that indicates the ability of concrete to last a long time without a significant loss in its *** this study,the freeze-thaw resistance of polymer concrete containing different polymer contents was explored and compared to various conventional cement ***’fresh and hardened properties were assessed for their workability,air content,and compressive *** mass loss,length change,dynamic modulus of elasticity,and residual compressive strength were determined for all types of concretes subjected to freeze-thaw cycles according to ASTM C666-procedure *** showed that polymer concrete(PC)specimens prepared with higher dosages of polymer contents possessed better freeze-thaw durability compared to other *** high durability performance of PCs is mainly due to their impermeable microstructures,absence of water in their structure,and the high bond strength between aggregates and a polymer *** is also indicated that the performance of high-strength concrete containing air-entraining admixture is comparable with PC having optimum polymer content in terms of residual compressive strength,dynamic modulus of elasticity,mass loss,and length change.

关键词： durability test freeze-thaw resistance polymer concrete residual compressive strength ASTM C666-15

An ensemble method for data stream classification in the presence of concept drift

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信息与电子工程前沿：英文版 2015年第12期16卷 1059-1068页

作者： omid ABBASZADEH Ali AMIRI Ali Reza KHANTEYMOORI Department of Computer Engineering University of Zanjan

One recent area of interest in computer science is data stream management and processing. By ‘data stream', we refer to continuous and rapidly generated packages of data. Specific features of data streams are immense volume, high production rate, limited data processing time, and data concept drift; these features differentiate the data stream from standard types of data. An issue for the data stream is classification of input data. A novel ensemble classifier is proposed in this paper. The classifier uses base classifiers of two weighting functions under different data input conditions. In addition, a new method is used to determine drift, which emphasizes the precision of the algorithm. Another characteristic of the proposed method is removal of different numbers of the base classifiers based on their quality. Implementation of a weighting mechanism to the base classifiers at the decision-making stage is another advantage of the algorithm. This facilitates adaptability when drifts take place, which leads to classifiers with higher efficiency. Furthermore, the proposed method is tested on a set of standard data and the results confirm higher accuracy compared to available ensemble classifiers and single classifiers. In addition, in some cases the proposed classifier is faster and needs less storage space.

关键词： Data stream Classificaion Ensemble classifiers Concept drift

Thermally Stable and Organo-soluble Polyamides Containing Triazine Rings and Ether Linkages in the Main Chain: Synthesis and Characterization

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Chinese Journal of Polymer Science 2015年第1期33卷 109-117页

作者： Mohsen Hajibeygi Khalil Faghihi Majid Khodaei-tehrani Zeinab Mirzakhanian Faculty of Chemistry Kharazmi University 15719-14911 Tehran Iran Department of Chemistry Faculty of Science Arak University Arak 38156-8-8349 Iran Department of Chemistry Arak Branch Islamic Azad UniversityArak Iran

In order to synthesize new polyamide（PA） 5 and copolyamides（Co PA） 7a-7d, a new-type of dicarboxylic acid containing triazine ring was successfully synthesized from 2,4-dichloro-6-methoxy-s-triazine 1 and 4-aminobenzoic acid. New polyamide 5 containing triazine moiety was prepared from 4,4＇-（6-methoxy-1,3,5-triazine-2,4-diyl）bis（azanediyl）dibenzoic acid 3 and 4,4′-diaminodiphenylether by direct polycondensation reaction. Then new series thermally stable copolyamides 7a-7d with high solubility in common organic solvents were synthesized from the direct polycondensation reaction of diacid 3 as a first monomer, aliphatic-aromatic diacids 6a-6d as second diacids and 4,4′-diaminodiphenylether. All of the above polymers were fully characterized by 1H-NMR and FTIR spectroscopy, elemental analysis（CHN）, inherent viscosity, solubility tests, gel permeation chromatography（GPC）, differential scanning calorimetry（DSC） and thermogravimetric analysis（TGA）. The resulted Co PAs 7a-7d have shown good inherent viscosities, solubility and thermal properties.

关键词： Polyamide Thermally stable Organo-soluble Polycondensation Triazine.

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

p53 modifications:exquisite decorations ofthe powerful guardian

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Journal of Molecular Cell Biology 2019年第7期11卷 564-577页

作者： Yanqing Liu omid Tavana Wei Gu Institute for Cancer Genetics College of Physicians and SurgeonsColumbia UniversityNew YorkNY 10032USA Department of Pathology and Cell Biology College of Physicians and SurgeonsColumbia UniversityNew YorkNY 10032USA Herbert Irving Comprehensive Cancer Center College of Physicians and SurgeonsColumbia UniversityNew YorkNY 10032USA

The last 40 years have witnessed how p53 rose from a viral binding protein to a central factor in both stress responses and tumor *** exquisite regulation of p53 functions is of vital importance for cell fate *** the multiple layers of mechanisms controlling p53 function,posttranslational modifications (PTMs) represent an efficient and precise *** p53 PTMs include phosphorylation,ubiquitination,acetylation,and ***,other PTMs like sumoylation,neddylation,O-GlcNAcylation,adenosine diphosphate (ADP)-ribosylation,hydroxylation,and p-hydroxybutyrylation are also shown to play various roles in p53 *** independent action or interaction,PTMs affect p53 stability,conformation,localization,and binding *** of the PTM-related pathway is among the major causes of p53-associated developmental disorders or diseases,especially in *** review focuses on the roles of different p53 modification types and shows how these modifications are orchestrated to produce various outcomes by modulating p53 activities or targeted to treat different diseases caused by p53 dysregulation.

关键词： p53 acetylation deacetylation phosphorylation ubiquitination methylation transcriptional regulation