检索结果-南通市图书馆

A gated recurrent unit model to predict Poisson’s ratio using deep learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 123-135页

作者： Fahd Saeed Alakbari Mysara Eissa Mohyaldinn Mohammed Abdalla Ayoub ibnelwaleed a.hus.ein Ali Samer Muhsan Syahrir Ridha Abdullah Abduljabbar Salih Petroleum Engineering Department Universiti Teknologi PETRONAS32610Bandar Seri IskandarPerakMalaysia Institute of Hydrocarbon Recovery Universiti Teknologi PETRONAS32610Bandar Seri IskandarPerakMalaysia Gas Processing Center College of EngineeringQatar UniversityP.O.Box 2713DohaQatar Department of Chemical Engineering College of EngineeringQatar UniversityP.O.Box 2713DohaQatar Mechanical Engineering Department Universiti Teknologi PETRONAS32610Bandar Seri IskandarPerakMalaysia

Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand *** models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical *** this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error *** GRU model showed the proper trends,and the model data ranges were wider than previous *** GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other *** GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,*** group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs.

关键词： Static Poisson’s ratio Deep learning Gated recurrent unit(GRU) Sand control Trend analysis Geomechanical properties

Investigation of dense slurry suspensions with coaxial mixers:Influences of design variables through tomography and mathematical modelling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2022年第6期20卷 1-16页

作者： Prakash Mishra Farhad ein-Mozaffari Department of Chemical Engineering Ryerson UniversityTorontoM5B 2K3Canada

The coaxial mixers enhance the suspension of concentrated slurries in an agitated *** this research work,the complex slurry suspension and dissemination behavior in a coaxial slurry mixing system(comprised of a close clearance anchor rotating with a low speed and an inner axial impeller rotating with a high speed)was analyzed employing ERT(electrical resistance tomography,a non-intrusive flow visualization technique),and computational fluid dynamics(CFD).The numerical models were validated by comparing the axial solid concentration profiles generated using the ERT data and the CFD simulation *** influences of various important parameters such as the diameter of the inner axial impeller,the inner impeller type,and the inner impeller spacing on the hydrodynamic characteristics of the slurry suspensions in a coaxial mixing vessel were thoroughly *** radial and axial velocity profiles of solid particles were generated using the validated mathematical *** assessment of energy loss due to the solid-solid collisions,the particle-fluid frictions,and the particle-vessel wall collisions was *** evaluation of optimum inner impeller clearance and inner impeller diameter is essential to attain a high degree of solids suspension and dissemination in a coaxial slurry mixing system.

关键词： Coaxial mixer Slurry suspension Homogeneity Mixing index Electrical resistance tomography(ERT) Computational fluid dynamics(CFD)

Effect of impeller type on mixing of highly concentrated slurries of large particles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2020年第3期18卷 88-99页

作者： Argang Kazemzadeh Farhad ein-Mozaffari Ali Lohi Department of Chemical Engineering Ryerson University350 Victoria StreetTorontoM5B 2K3Canada

Many chemical engineering processes deal with dense suspensions of large solid particles in *** of such systems are difficult to predict because the many solid particles strongly affect the hydrodynamics produced by the *** main objective was to assess the performances of the PBT,A310,and PF3 impellers in agitating highly concentrated slurries of large *** resistance tomography was used to determine the degree of homogeneity and solid particle distribution within the slurry *** gain more insight into the complex behavior of the flow inside the dense suspensions,computational fluid dynamics simulations were conducted using a Eulerian-Eulerian multiphase *** qualitative and quantitative analyses were performed to obtain details on the dispersed solid phase distribution and its effect on the mixing *** found that the PBT impeller was the most efficient in terms of consuming power and generating velocity and turbulent kinetic energy within the mixing tank.

关键词： Suspension Highly concentrated slurry Electrical resistance tomography Computational fluid dynamics Homogeneity

Mixing and segregation assessment of bi-disperse solid particles in a double paddle mixer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2023年第3期74卷 184-199页

作者： Behrooz Jadidi Mohammadreza Ebrahimi Farhad ein-Mozaffari Ali Lohi Department of Chemical Engineering Ryerson University350 Victoria StreetTorontoM5B 2K3Canada

A double paddle blender's flow patterns and mixing mechanisms were analyzed using discrete element method(DEM)and *** mixing performance of this type of the blender containing bi-disperse particles has been rarely studied in the ***-Burman design of experiments(DoE)methodology was used to calibrate the DEM input ***,the impact of the particle number ratio,vessel fill level,and paddle rotational speed on mixing performance was investigated using the calibrated DEM *** mixing performance was assessed using relative standard deviation and segregation *** performance was significantly affected by the paddle rotational speed and particle number ***,the Peclet number and diffusivity coefficient were used to evaluate the mixing mechanism in the *** revealed that the diffusion was the predominant mixing mechanism,and the best mixing performance was observed when the diffusivity coefficients of 3 mm and 5 mm particles were almost equal.

关键词： Double paddle blender Discrete element method(DEM) Granular mixing Mixing kinetics and mechanism Bi-disperse solid particles

Circulation intensity and axial dispersion of non-cohesive solid particles in a V-blender via DEM simulation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2013年第6期11卷 619-626页

作者： Parisa Tahvildarian Farhad ein-Mozaffari Simant R.Upreti Department of Chemical Engineering Ryerson University

In this study, discrete element method （DEM） was employed to simulate the movement of non-cohesive mono-dispersed particles in a V-blender along with particle-particle and particle-boundary interactions. To validate the model, DEM results were successfully compared to positron emission particle tracking （PEPT） data reported in literature. The validated model was then utilized to explore the effects of rotational speed and fill level on circulation intensity and axial dispersion coefficient of non-cohesive particles in the V-blender. The results showed that the circulation intensity increased with an increase in the rotational speed from 15 to 60 rpm. As the fill level increased from 20% to 46%, the circulation intensity decreased, reached its minimum value at a fill level of 34% for all rotational speeds, and did not change significantly at fill levels greater than 34%. The DEM results also revealed that the axial dispersion coefficient of particles in the V-blender was a linear function of the rotational speed. These trends were in good agreement with the experimentallv determined values reported bv previous researchers.

关键词： Powder mixing Discrete element method Circulation intensity Dispersion coefficient V-blender

Benzimidazole and its derivatives as cancer therapeutics:The potential role from traditional to precision medicine

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2023年第2期13卷 478-497页

作者： Yeuan Ting Lee Yi Jer Tan Chern ein Oon Institute for Research in Molecular Medicine(INFORMM) Universiti Sains Malaysia11800 MindenPenangMalaysia

Cancer is the second leading cause of mortality globally which remains a continuing threat to human health *** insensitivity and resistance are critical hurdles in cancer treatment;therefore,the development of new entities targeting malignant cells is considered a high *** therapy is the cornerstone of precision *** synthesis of benzimidazole has garnered the attention of medicinal chemists and biologists due to its remarkable medicinal and pharmacological *** has a heterocyclic pharmacophore,which is an essential scaffold in drug and pharmaceutical *** studies have demonstrated the bioactivities of benzimidazole and its derivatives as potential anticancer therapeutics,either through targeting specific molecules or non-gene-specific *** review provides an update on the mechanism of actions of various benzimidazole derivatives and the structure-activity relationship from conventional anticancer to precision healthcare and from bench to clinics.

关键词： Benzimidazole derivatives Targeted therapy Anticancer Precision medicine

Statistical Entropy of Three-Dimensional Spherical Spacetime

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第3期17卷 177-179页

作者： WANG ein SU Ru-Keng FENG Shi-Xiang Department of Physics Fudan UniversityShanghai 200433 Department of Physics Shanghai Normal UniversityShanghai 200234 Department of Modern Physics University of Science and Technology of ChinaHefei 230026

Ey means of conformal Held theory,we have related the degrees of freedom of microstates to the entropy of three-dimensional charged black hole as well as the entanglement entropy of three-dimensional De Sitter spacetime,We have shown that the degrees of freedom of the conformal theory responsible for the entropy represent states on the horizon and localized in physical spacetime.

关键词： entropy conformal states

Species traits and shoot-root biomass allocation in 20 dry-grassland species

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Plant Ecology 2018年第2期11卷 273-285页

作者： Iveta husáková Jacob Weiner Zuzana Münzbergová Department of Botany Faculty of ScienceCharles UniversityBenátská2CZ-12801 PragueCzech Republic Institute of Botany Academy of Sciences of the Czech RepublicZámek 1CZ-25243 PrůhoniceCzech Republic Department of Plant and Environmental Sciences University of CopenhagenThorvaldsensvej 40DK-1871 FrederiksbergDenmark

Aims A plant has a limited amount of resources at any time and it allo-cates them to different *** spite of the large number of previous studies on allocation patterns within single species,knowledge of general patterns in species allocation is still very *** is because each study was done in different condi-tions using different methodology,making generalization *** investigate intraspecific above-versus below-ground biomass allocation among individuals across a spectrum of dry-grassland plant species at two different developmental stages and ask whether allocation is age-and species specific,and whether differences among species can be explained by their life-history traits and *** We collected data on above-and below-ground biomass of seedlings and adult plants of 20 species from a common garden *** analysed data on shoot-root biomass allocation allometrically and studied the relationship between the allometric exponents(slopes on log-log scale),species life-history traits and phylogenetic *** Findings We found isometric as well as allometric patterns of biomass alloca-tion in the studied *** and adult individuals of more than half of the species differed in their above-versus below-ground biomass allometric *** and adult individuals of the remaining species differed in their allometric coefficients(inter-cepts).Annual species generally allocated proportionally more to above-than below-ground biomass as seedlings than as adults,whereas perennial species showed the opposite *** life-history traits,such as plant life span,age of first flowering,month in which the species begin flowering and specific leaf area were much more important in explaining differences in shoot-root allometry among species than were phylogenetic *** suggests that allocation patterns vary greatly among closely related species but can be predicted based on species life-hi

关键词： above-ground biomass below-ground biomass allometry isometry seedling adult plant life-history traits phylogenetic relatedness root-shoot ratio

Using the discrete element method to assess the mixing of polydisperse solid particles in a rotary drum

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2016年第2期14卷 133-142页

作者： Basel Alchikh-Sulaiman Meysam Alian Farhad ein-Mozaffari Ali Lohi Simant R. Upreti Department of Chemical Engineering Ryerson University 350 Victoria Street Toronto Canada M5B 2K3

Despite the wide applications of powder and solid mixing in industry, knowledge on the mixing of polydisperse solid particles in rotary drum blenders is lacking. This study investigates the mixing of monodisperse, bidisperse, tridisperse, and polydisperse solid particles in a rotary drum using the dis- crete element method. To validate the model developed in this study, experimental and simulation results were compared. The validated model was then employed to investigate the effects of the drum rotational speed, particle size, and initial loading method on the mixing quality. The degree of mixing of polydis- perse particles was smaller than that for monodisperse particles owing to the segregation phenomenon. The mixing index increased from an initial value to a maximum and decreased slightly before reaching a plateau for bidisperse, tridisperse, and polydisperse particles as a direct result of the segregation of par- ticles of different sizes. Final mixing indices were higher for polydisperse particles than for tridisperse and bidisperse particles. Additionally, segregation was weakened by introducing additional particles of intermediate size. The best mixing of bidisperse and tridisperse particles was achieved for top-bottom smaller-to-larger initial loading, while that of polydisperse systems was achieved using top-bottom smaller-to-larger and top-bottom larger-to-smaller initial loading methods.

关键词： Rotary drum mixer Discrete element method Mixing index Polydisperse particles Loading methods