检索结果-南通市图书馆

Research on Cavitation Characteristics and Influencing Factors of Herringbone Gear Pump

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computer modeling in Engineering & Sciences 2024年第6期139卷 2917-2946页

作者： Jinlong Yang Kwang-Hee Lee Chul-Hee Lee department of Mechanical Engineering of Inha University Incheon22212South Korea

Cavitation is a common issue in pumps,causing a decrease in pump head,a fall in volumetric efficiency,and an intensification of outlet flow *** is one of the main hazards that affect the regular operation of the *** on pump cavitation mainly focuses on mixed flow pumps,jet pumps,external spur gear pumps,***,there are few cavitation studies on external herringbone gear *** addition,pumps with different working principles significantly differ in the flow and complexity of the internal flow ***,it is urgent to study the cavitation characteristics of external herringbone gear *** with experimentalmethods,visual research and cavitation area identification are achieved through computation fluid dynamic(CFD),and changing the boundary conditions and shape of the gear rotor is *** simulation yields a head error of only 0.003%under different grid numbers,and the deviation between experimental and simulation results is less than 5%.The study revealed that cavitation causes flow pulsation at the outlet,and the cavitation serious area is mainly distributed in the meshing gap and meshing *** can be inhibited by reducing the speed,increasing the inlet pressure,and changing the helix angle can be *** example,when the inlet pressure is 5 bar,the maximumgas volume fraction in themeshing area is less than 50%.These results provide a reference for optimizing the design and finding the optimal design parameters to reduce or eliminate cavitation.

关键词： Herringbone gear pump cavitation rotating speed inlet pressure helix angle TwinMesh

Coupling Analysis of Multiple Machine Learning Models for Human Activity Recognition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第6期79卷 3783-3803页

作者： Yi-Chun Lai Shu-Yin Chiang Yao-Chiang Kan Hsueh-Chun Lin department of Public Health China Medical UniversityTaichung406040Taiwan department of Information and Telecommunications Engineering Ming Chuan UniversityGui-ShanTaoyuan333Taiwan department of Electrical Engineering Yuan Ze UniversityChung-Li32003Taiwan department and Institute of Health Service Administrations China Medical UniversityTaichung406040Taiwan

Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation *** study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their effectiveness in *** analytical dataset comprises 561 features sourced from the UCI-HAR database,forming the foundation for training the ***,the MHEALTH database is employed to replicate the modeling process for comparative purposes,while inclusion of the WISDM database,renowned for its challenging features,supports the framework’s resilience and *** ML-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIS),support vector machine(SVM),and random forest(RF),for data *** contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature ***,the recursive feature elimination(RFE)algorithm,which drives an ML-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model *** best accuracies of the ANFIS,SVM,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,*** analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,SVM,and ANFIS models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,***,when applied to the WISDM dataset,the DL-based and ML-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research *** conclusion,the proposed framework yields HAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications.

关键词： Human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination

Multidisciplinary design optimization of a dual-spin guided vehicle

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第7期37卷 133-148页

作者： Jalal Karimi Mohammad Reza Rajabi Seyed Hossein Sadati Seyed Mahid Hosseini department of Aerospace Engineering Malek Ashtar University of TechnologyTehranIran

In this research,a Multidisciplinary design Optimization approach is proposed for the dual-spin guided flying projectile design considering external and internal parts of the body as design *** this way,a parametric formulation is *** related disciplines,including structure,aerodynamics,guidance,and control are *** total mass,maximum aerodynamic control effectiveness,minimum miss distance,maximum yield stress in all subsystems,controllability and gyroscopic stability constraints are some of objectives/constraints taken into *** problem is formulated in All-At-Ones Multidisciplinary design Optimization approach structure and solved by Simulated Annealing and minimax *** optimal configurations are evaluated in various *** resulted optimal configurations have met all design objectives and constraints.

关键词： Flying projectile optimal design All-at-ones multidisciplinary optimization Structure discipline Guidance and control discipline Aerodynamic discipline

维普期刊数据库

Predicting the Mechanical Behavior of a Bioinspired Nanocomposite through Machine Learning

在线全文

学校读者我要写书评

暂无评论

Computer modeling in Engineering & Sciences 2024年第8期140卷 1299-1313页

作者： Xingzi Yang Wei Gao Xiaodu Wang Xiaowei Zeng department of Mechanical Engineering University of Texas at San AntonioSan AntonioTX78249USA department of Mechanical Engineering Texas A&M UniversityCollege StationTX77843USA

The bioinspired nacre or bone structure represents a remarkable example of tough,strong,lightweight,and multifunctional structures in biological materials that can be an inspiration to design bioinspired high-performance *** bioinspired structure consists of hard grains and soft material *** the material interface has a very low volume percentage,its property has the ability to determine the bulk material *** learning technology nowadays is widely used in material science.A machine learning model was utilized to predict the material response based on the material interface properties in a bioinspired *** model was trained on a comprehensive dataset of material response and interface properties,allowing it to make accurate *** results of this study demonstrate the efficiency and high accuracy of the machine learning *** successful application of machine learning into the material property prediction process has the potential to greatly enhance both the efficiency and accuracy of the material design process.

关键词： Bioinspired nanocomposite computational model machine learning finite element material interface

Robust control of isopropyl benzene production process using H_(∞) loop shaping control scheme

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 Control and Decision 2024年第1期11卷 153-163页

作者： Vinila Mundakkal Lakshmanan Aparna Kallingal Sreepriya Sreekumar department of Chemical Engineering National Institute of Technology CalicutKozhikodeKeralaIndia department of Robotics and Automation Adi Shankara Institute of Engineering and TechnologyKaladyIndia

This paper discusses robust control strategy for isopropyl benzene production process using the method of loop shaping H_(∞) *** cumene production process is a part of phenol plant in HOCL,Kochi.H_(∞) control of the propylene concentration is done *** H_(∞) controller is derived from the linearised model of the *** optimal H_(∞) controller is obtained by simplifying two algebraic Riccati *** proposed PID-like H_(∞) controller provides a single tuning parameter which makes the controller design more *** proposed controller has been compared with other robust controllers like H_(2) and *** H_(∞) controller is found to be superior in a wide frequency range and has a feature of low distortion and good regulating *** reactor model has been developed in COMSOL Multiphysics with the parameters obtained from HOCL plant,*** model extracted is reduced using model order reduction for the controller design.

关键词： Cumene reactor H_(∞)loop shaping model order reduction Riccati equation PID control stability robustness

Towards implementation of alloy-specific thermo-fluid modelling for laser powder-bed fusion of Mg alloys

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 Magnesium and Alloys 2024年第6期12卷 2327-2344页

作者： Mohammad Hoseini-Athar Mikael Ersson Peter Hedström department of Material Science and Engineering KTH Royal Institute of TechnologyStockholmSE-10044 Sweden

Multi-physics thermo-fluid modeling has been extensively used as an approach to understand melt pool dynamics and defect formation as well as optimizing the process-related parameters of laser powder-bed fusion(L-PBF).However,its capabilities for being implemented as a reliable tool for material design,where minor changes in material-related parameters must be accurately captured,is still in *** the present research,first,a thermo-fluid computational fluid dynamics(CFD)model is developed and validated against experimental *** the predicted material properties of the pure Mg and commercial ZK60 and WE43 Mg alloys,parametric studies are done attempting to elucidate how the difference in some of the material properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the melt pool *** is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation mass *** viscosity and wider solidification range can increase the non-uniformity of temperature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and formation of ***,the WE43 alloy showed the best behavior in terms of defect formation and evaporation mass loss,providing theoretical support to the extensive use of this alloy in *** summary,this study suggests an approach to investigate the effect of materials-related parameters on L-PBF melting and solidification,which can be extremely helpful for future design of new alloys suitable for L-PBF.

关键词： Mg alloys Laser powder-bed fusion(L-PBF) Melt pool dynamics Computational fluid dynamics Fluid flow

维普期刊数据库

Optimization Algorithms of PERT/CPM Network Diagrams in Linear Diophantine Fuzzy Environment

在线全文

学校读者我要写书评

暂无评论

Computer modeling in Engineering & Sciences 2024年第4期139卷 1095-1118页

作者： Mani Parimala Karthikeyan Prakash Ashraf Al-Quran Muhammad Riaz Saeid Jafari department of Mathematics Bannari Amman Institute of TechnologySathyamangalamTamil Nadu638401India Basic Sciences department Preparatory Year DeanshipKing Faisal UniversityAl-Ahsa31982Saudi Arabia department of Mathematics University of the PunjabLahorePakistan College of Vestsjaelland South Herrestraede 11Slagelse4200Denmark

The idea of linear Diophantine fuzzy set(LDFS)theory with its control parameters is a strong model for machine learning and optimization under *** activity times in the critical path method(CPM)representation procedures approach are initially static,but in the Project Evaluation and Review Technique(PERT)approach,they are *** study proposes a novel way of project review and assessment methodology for a project network in a linear Diophantine fuzzy(LDF)*** LDF expected task time,LDF variance,LDF critical path,and LDF total expected time for determining the project network are all computed using LDF numbers as the time of each activity in the project *** primary premise of the LDF-PERT approach is to address ambiguities in project network activity timesmore simply than other approaches such as conventional PERT,Fuzzy PERT,and so *** LDF-PERT is an efficient approach to analyzing symmetries in fuzzy control systems to seek an optimal *** also present a new approach for locating LDF-CPM in a project network with uncertain and erroneous activity *** the available resources and activity times are imprecise and unpredictable,this strategy can help decision-makers make better judgments in a project.A comparison analysis of the proposed technique with the existing techniques has also been *** suggested techniques are demonstrated with two suitable numerical examples.

关键词： Linear Diophantine fuzzy graphs project management PERT CPM linear Diophantine fuzzy numbers score function accuracy function

Cellular interplay to 3D in vitro microphysiological disease model:cell patterning microbiota-gut-brain axis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bio-design and Manufacturing 2024年第3期7卷 320-357页

作者： Kamare Alam Lakshmi Nair Souvik Mukherjee Kulwinder Kaur Manjari Singh Santanu Kaity Velayutham Ravichandiran Sugato Banerjee Subhadeep Roy department of Pharmacology and Toxicology National Institute of Pharmaceutical Education and ResearchKolkataWest Bengal 700054India department of Pharmaceutical Sciences Assam UniversitySilchar 788011India department of Pharmaceutical Sciences Guru Ghasidas UniversityKoniBilaspur 495009C.G.India School of Pharmacy and Biomolecular Sciences RCSI University of Medicine and Health SciencesDublin D02 YN77Ireland Tissue Engineering Research Group Department of Anatomy and Regenerative MedicineRCSI University of Medicine and Health SciencesDublin D02 YN77Ireland department of Pharmaceutics National Institute of Pharmaceutical Education and ResearchKolkataWest Bengal 700054India department of Natural Products National Institute of Pharmaceutical Education and ResearchKolkataWest Bengal 700054India

The microbiota-gut-brain axis(MGBA)has emerged as a key prospect in the bidirectional communication between two major organ systems:the brain and the *** between the two organ systems allows the body to function without disease,whereas dysbiosis has long-standing evidence of etiopathological *** most common communication paths are the microbial release of metabolites,soluble neurotransmitters,and immune ***,each pathway is intertwined with a complex *** the emergence of in vitro models and the popularity of three-dimensional(3D)cultures and Transwells,engineering has become easier for the scientific understanding of neurodegenerative *** paper briefly retraces the possible communication pathways between the gut microbiome and the *** further elaborates on three major diseases:autism spectrum disorder,Parkinson’s disease,and Alzheimer’s disease,which are prevalent in children and the *** diseases also decrease patients’quality of ***,understanding them more deeply with respect to current advances in in vitro modeling is crucial for understanding the *** of MGBA in the laboratory uses many molecular technologies and biomaterial *** and organoids provide a more realistic picture of the cell and tissue structure than *** them with the Transwell system offers the advantage of compartmentalizing the two systems(apical and basal)while allowing physical and chemical cues between ***-edge technologies,such as bioprinting and microfluidic chips,might be the future of in vitro modeling,as they provide dynamicity.

关键词： Microbiota-gut-brain axis Neurodegeneration 3D disease model Organoid Transwell system

维普期刊数据库

Indispensable gutter layers in thin-film composite membranes for carbon capture

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2024年第8期9卷 1220-1238页

作者： Gengyi Zhang Haiqing Lin department of Chemical and Biological Engineering University at Buffalo The State University at New York

Industrial thin-film composite(TFC) membranes achieve superior gas separation properties from high-performance selective layer materials,while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing. However, the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity, while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers. This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance. We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results. Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed, and the strategies to improve their compatibility with the selective layer are highlighted, such as oxygen plasma treatment, polydopamine deposition, and surface grafting. Finally, we present the opportunities of the gutter layer design for practical applications.

关键词： Thin-film composite membranes Gutter layer Gas separation Carbon capture