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Normal Crossings Degenerations of Symplectic Manifolds

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Peking Mathematical Journal 2019年第3期2卷 275-351页

作者： mohammad farajzadeh tehrani Aleksey Zinger Simons Center for Geometry and Physics Stony Brook UniversityStony BrookNY 11794USA Department of Mathematics The University of IowaIowa CityIA 52242USA Department of Mathematics Stony Brook UniversityStony BrookNY 11794USA

We use local Hamiltonian torus actions to degenerate a symplectic manifold to a normal crossings symplectic variety in a smooth one-parameter *** construction,motivated in part by the Gross-Siebert and ***’s programs,contains a multifold version of the usual(two-fold)symplectic cut construction and in particular splits a symplectic manifold into several symplectic manifolds containing normal crossings symplectic divisors with shared irreducible components in one step.

关键词： symplectic manifold irreducible

Liquid injectivity in a SAG foam process:Effect of permeability

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Petroleum Science 2024年第1期21卷 302-314页

作者： Jia-Kun Gong Yuan Wang Ridhwan-Zhafri B.Kamarul Bahrim Raj-Deo Tewari mohammad-Iqbal Mahamad Amir Rouhi farajzadeh William Rossen College of Mechanics and Materials Hohai UniversityNanjing210098JiangsuChina College of Water Conservancy&Hydropower Engineering Hohai UniversityNanjing210098JiangsuChina PETRONAS Kuala Lumpur50088Malaysia Department of Geoscience and Engineering Delft University of Technology2628 CNDelftthe Netherlands Shell Global Solutions International B.V. 1031 HWAmsterdamthe Netherlands

Foam is utilized in enhanced oil recovery and CO_(2) ***-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in *** previous studies with similar permeability cores show that during SAG injection,several banks occupy the area near the well where fluid exhibits distinct ***,underground reservoirs are heterogeneous,often *** is crucial to understand the effect of permeability on fluid behaviour and injectivity in a SAG *** this work,coreflood experiments are conducted in cores with permeabilities ranging from 16 to 2300 *** observe the same sequence of banks in cores with different ***,the speed at which banks propagate and their overall mobility can vary depending on *** higher permeabilities,the gas-dissolution bank and the forced-imbibition bank progress more rapidly during liquid *** total mobilities of both banks decrease with *** utilizing a bank-propagation model,we scale up our experimental findings and compare them to results obtained using the Peaceman *** findings reveal that the liquid injectivity in a SAG foam process is misestimated by conventional simulators based on the Peaceman *** lower the formation permeability,the greater the error.

关键词： Foam Enhanced oil recovery Surfactant-alternating-gas Injectivity Permeability

Enhanced Sensitivity and Stability in Gelatin-Based Fricke gel Dosimeters:Impact of Benzoic Acid on Low-Dose Radiation Measurements

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Instrumentation 2024年 23-29页

作者： Seyed Amir Saeedi-Sini Sedigheh Sina mohammad Hossein Sadeghi Ebrahim farajzadeh Nuclear Engineering Department School of Mechanical EngineeringShiraz University Radiation Research Center School of Mechanical EngineeringShiraz University Secondary Standard Dosimetry Laboratory(SSDL) Pars Isotope Co.

Fricke gel dosimetry is a critical technique for accurate radiation dose measurement,leveraging the radiation-induced oxidation of ferrous to ferric ions within a hydrogel *** study aimed to advance the field by preparing and evaluating seventy-one Fricke gel dosimeter (FGD) samples with varying chemical compositions,focusing on the incorporation of benzoic *** gelatin-based samples demonstrated superior sensitivity,particularly for low-dose *** findings indicated that the sample without benzoic acid exhibited a 1.75 times higher sensitivity compared to the sample containing benzoic acid,with lower limits of detection at 0.04 Gy and 0.1 Gy,*** tests revealed temperature-dependent responses,with better performance observed under refrigerated *** was confirmed through consistent calibration curves across multiple ***,the dosimeters'responses varied with different radiation types,underscoring the need for specific *** study concludes that while benzoic acid slightly reduces sensitivity,it provides consistent responses across various radiation energies,suggesting its potential as a beneficial additive in diverse clinical *** research contributes to the ongoing optimization of FGDs for precise radiation dose assessment.

关键词：

Auto-tuning PVT data using multi-objective optimization:Application of NSGA-II algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi mohammad Madani mohammad Jafarzadegan Reservoir Engineering Systems Petroleum Engineering DepartmentMain Office Building of National Iranian South Oil Company(NISOC)AhvazIran Reservoir Engineering Division Petroleum Engineering DepartmentPetroleum Engineering and Development Company(PEDEC)TehranIran Combined Planning Management National Iranian Oil Company(NIOC)TehranIran

Reservoir simulation is known as perhaps the most widely used,accurate,and reliable method for field development in the petroleum *** integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS ***,EOS models are tuned iteratively through arduous workflows against experimental PVT ***,this comes with a number of drawbacks such as forcingly using weight factors,which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective *** order to illustrate the robustness of the presented technique,three different PVT samples are used,including two black-oil and one gas condensate *** utilize PengRobinson EOS during all the manual and auto-tuning *** of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is *** addition,the proposed method,contrary to the manual matching process,provides the engineer with several matched solutions,which allows them to select a match based on the engineering background to be best amenable to the problem at *** addition,the proposed technique is fast,and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

Investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad M.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical *** study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)*** analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(ITS),and permeability tests were ***,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were *** the final stage,SFP was compared to HMA in terms of engineering characteristics and *** to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HMA had a better performance in fracture tests,including SCB *** to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,***,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the ***,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

Recent Progress in Bionic Hydrogels for Articular Cartilage:Tribological and Mechanical Characteristics

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Journal of Bionic Engineering 2024年第2期21卷 653-673页

作者： mohammad Javan Almasi Dangsheng Xiong School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Cartilage regeneration and repair are considered clinical challenges since cartilage has limited capability for *** tissue-engineered materials have the ability to repair cartilage,they have weak mechanical characteristics and cannot resist long-term *** the other hand,surgery to replace the joint is frequently done to treat significant cartilage deterioration these ***,the materials that are being used for replacement have high friction coefficients,lack shock absorption functions,and lack *** research on natural articular cartilage structure and function may lead to bionic hydrogels,which have suitable physicochemical and biological characteristics(e.g.,tribological and mechanical properties and the ability to support loadbearing capability),but need *** on their tribological and mechanical characteristics,the current review highlights the most recent advancements of bionic hydrogels used for articular cartilage,highlighting both the field's recent progress and its potential for future *** this reason,firstly,some important property improvement methods of bionic hydrogels are discussed and then,the recent findings of various research on the making of those bionic materials are provided and *** seems that by using some modifications such as product design,surface treatments,animal tests,controlling the isoelectric point of hydrogels,and computer simulation,the intended mechanical and tribological characteristics of natural articular cartilage may be attained by the bionic hydrogels.

关键词： Bionic hydrogel Articular cartilage Mechanical property Tribological property Lubrication

Ultrasensitive plasmonic sensor based on MDM waveguide containing Persian Orsi window cavities for refractive index and blood plasma sensing

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Optoelectronics Letters 2024年第7期20卷 406-411页

作者： mohammad Ghanavati mohammad Azim Karami School of Electrical Engineering Iran University of Science and TechnologyTehran 16846-13114Iran12

We developed a plasmonic refractive index(RI)with a metal-dielectric-metal(MDM)structure that utilizes two Persian Orsi windows-like separated cavities with a high figure of merit(FoM)and *** simulated and optimized Ag-air-Ag MDM sensor for surface plasmon resonance(SPR)offers high RI sensitivity(SRI)and the ability to detect blood plasma concentration(BPC).The results verified that structural parameters have an effect on SRI,full width at half maximum(FWHM),FoM,sensitivity of blood plasma(S_(p))for right and left peaks,whose values are 1345.45 nm·RIU^(−1),32 nm,42.04 RIU^(−1),0.26 and 0.19 nm·L·g^(-1),*** proposed design opens a new horizon in sensor development.

关键词： index utilize MDM

Enhanced adaptive nonlinear extended state observer for pure feedback systems with matched and mismatched disturbances

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Control Theory and Technology 2024年第2期22卷 254-268页

作者： Mahtab Delpasand mohammad Farrokhi School of Electrical Engineering Iran University of Science and TechnologyTehran16846-13114Iran Center of Excellence for Modelling and Control of Complex Systems Iran University of Science and TechnologyTehran16846-13114Iran

In this paper, an enhanced adaptive nonlinear extended state observer (EANESO) for single-input single-output pure feedback systems in the presence of external time-varying disturbances is proposed. In this paper, a nonlinear system with matched and mismatched disturbances is considered. The conventional extended state observer (ESO) can only be applied to systems that are in the form of integral chains. Moreover, this method has limitations in the face of mismatched disturbances. In the presence of time-varying disturbances, the traditional ESOs cannot estimate the disturbances accurately. To overcome this limitation, an EANESO is proposed in this paper. The main idea is to design the nonlinear ESO (NESO) to estimate the states of the system and multiple disturbances simultaneously. The observer gains are considered time-varying and adjusted with adaptation laws to improve the estimation accuracy and overcome the peaking phenomenon. Next, the proposed controller is designed based on output feedback to eliminate the effects of multiple disturbances and stabilize the closed-loop system. Subsequently, the stability analysis of the closed-loop system and convergence of the observer error are discussed. Finally, the proposed method is applied to the inverted pendulum system. The simulated results show good performance of the proposed method as compared with a recently published scheme in the related literature.

关键词： Nonlinear extended state observer Enhanced adaptive extended state observer Adaptation law Multiple-channel disturbances Inverted pendulum system Time-varying gain

The modeling non-sequential double ionization of helium atom under highintensity femtosecond laser pulses with shielding charge approximation

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Communications in Theoretical Physics 2024年第2期76卷 151-156页

作者： Marjan Zakavi mohammad Sabaeian Department of Physics Faculty of ScienceShahid Chamran University of AhvazIran Center for Research on Laser and Plasma Shahid Chamran University of AhvazIran

In this study,we successfully extracted the‘knee structure’for non-sequential double ionization(NSDI)in the helium *** achieve this,for the first time,we solved the time-dependent Schrödinger equation in three dimensions for the helium atom,utilizing the shielding charge *** findings corroborate prior observations by Wang et al[Wang and Eberly,***.105,083001(2010)],demonstrating that NSDI occurs within a narrower time window in circular polarization compared to linear *** a result,the yield of linear polarization was higher than that of circular polarization,aligning with the previously reported ***,in the case of circular polarization,the time window further narrows with increasing intensity,attributed to a decrease in the time-of-flight.

关键词： NSDI knee structure TDSE shielding charge helium 3D-TDSE