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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 81-100页

作者： S.SAUrABH r.KIrAN D.SINGH r.VAISH V.S.CHAUHAN School of Mechanical and Materials Engineering Indian Institute of Technology Mandi

Bio-inspired helicoidal composite laminates, inspired by the intricate helical structures found in nature, present a promising frontier for enhancing the mechanical properties of structural designs. Hence, this study provides a comprehensive investigation into the nonlinear free vibration and nonlinear bending behavior of bio-inspired composite plates. The inverse hyperbolic shear deformation theory(IHSDT) of plates is employed to characterize the displacement field, with the incorporation of Green-Lagrange nonlinearity. The problem is modeled using the C0finite element method(FEM), and an in-house code is developed in the MATLAB environment to solve it numerically. Various helicoidal layup configurations including helicoidal recursive(Hr), helicoidal exponential(HE), helicoidal semi-circular(HS), linear helicoidal(LH), and Fibonacci helicoidal(FH)with different layup sequences and quasi-isotropic configurations are studied. The model is validated, and parametric studies are conducted. These studies investigate the effects of layup configurations, side-to-thickness ratio, modulus ratios, boundary conditions, and loading conditions at different load amplitudes on the nonlinear vibration and nonlinear bending behaviors of bio-inspired composite plates. The results show that the laminate sequence exerts a substantial impact on both nonlinear natural frequencies and nonlinear bending behaviors. Moreover, this influence varies across different side-to-thickness ratios and boundary conditions of the bio-inspired composite plate.

关键词：

PLATFOrM SELECTION FOr COMPLEX SYSTEMS:BUILDING AUTOMATION SYSTEMS

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Journal of Systems Science and Systems Engineering 2014年第4期23卷 415-438页

作者： Geerten van de Kaa Henk Jan de Vries jafar rezaei Faculty of Technology Policyand ManagementDelft University of TechnologyJaffalaan 52628BX DelftThe Netherlands rotterdam School of Management Erasmus UniversityBurgemeester Oudlaan 503062PARotterdam The Netherlands Faculty of TechnologyPolicyand ManagementDelft University of Technology Jaffalaan 52628BX DelftThe Netherlands Faculty of Technology Policyand ManagementDelft University of Technology Jaffalaan 52628BXDelftThe Netherlands

Automation systems for buildings interconnect components and technologies from the information technology industry and the telecommunications *** these industries,existing platforms and new platforms（that are designed to make building automation systems work） compete for market acceptance and consequently several platform battles among suppliers for building automation networking are being *** is unclear what the outcome of these battles will be and also which factors are important in achieving platform *** the fuzziness of decision makers＇ judgments into account,a fuzzy multi-criteria decision-making methodology called the Fuzzy Analytic Hierarchy Process is applied to investigate the importance of such factors in platform battles for building automation *** present the relative importance of the factors for three types of platforms（subsystem platforms,system platforms,and evolved subsystem platforms）.The results provide a first indication that the set of important factors differs per type of *** example,when focusing on other stakeholders,for subsystem platforms,the previous installed base is of importance;for system platforms,the diversity of the network of stakeholders is essential;and for evolved subsystem platforms,the judiciary is an important factor.

关键词： Building automation system complex system platform Fuzzy Analytic Hierarchy Process(AHP) multi-criteria decision-making(MCDM)

Environmental impact prediction using remote sensing images

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 381-390页

作者： Pezhman rOUDGArMI Masoud MONAVArI Jahangir FEGHHI jafar NOUrI Nematollah KHOrASANI Tehran Agricultural and Natural resources research Center Agricultural Research and Education Organization (AREO) Tehran Iran Department of Environmental Management Graduate School of the Environment and Energy Science and Research Campus IAU Tehran Iran Department of Environmental Science Graduate School of the Environment and Energy Science and Research Campus IAU Tehran Iran Department of Forestry and Forest Economics Faculty of Natural Resources University of Tehran Karaj Iran Department of Environmental Health Engineering School of Public Health and Center for Environmental Research Medical Science University of Tehran Tehran Iran Department of Environmental Science Faculty of Natural ResourcesUniversity of TehranKarajIran

Environmental impact prediction is an important step in many environmental studies. A wide variety of methods have been developed in this concern. During this study, remote sensing images were used for environmental impact prediction in ro-batkarim area, Iran, during the years of 2005～2007. It was assumed that environmental impact could be predicted using time series satellite imageries. Natural vegetation cover was chosen as a main environmental element and a case study. Environmental impacts of the regional development on natural vegetation of the area were investigated considering the changes occurred on the extent of natural vegetation cover and the amount of biomass. Vegetation data, land use and land cover classes (as activity factors) within several years were prepared using satellite images. The amount of biomass was measured by Soil-adjusted Vegetation Index (SAVI) and Normalized Difference Vegetation Index (NDVI) based on satellite images. The resulted biomass estimates were tested by the paired samples t-test method. No significant difference was observed between the average biomass of estimated and control samples at the 5% significance level. Finally, regression models were used for the environmental impacts prediction. All obtained regression models for prediction of impacts on natural vegetation cover show values over 0.9 for both correlation coefficient and r-squared. According to the resulted methodology, the prediction models of projects and plans impacts can also be developed for other environmental elements which may be derived using time series remote sensing images.

关键词： Environmental impact remote sensing Prediction Vegetation Biomass

Immobilization of organophosphorus hydrolase enzyme by covalent attachment on modified cellulose microfibers using different chemical activation strategies:Characterization and stability studies

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Chinese Journal of Chemical Engineering 2019年第1期27卷 191-199页

作者： Meisam Sharifi Seyed-Mortaza robatjazi Minoo Sadri jafar Mohammadian Mosaabadi Department of Bioscience and Biotechnology Malek Ashtar University of Technology

The plant cellulose powder was activated by two different methods using 1,4-butanediol diglycidyl ether(BTDE)and 1,1′-Carbonyldiimidazole(CDI) as the chemical coupling *** hydrolase(OPH) from Flavobacterium ATCC 27551 was immobilized on any of activated support through covalent *** optimal conditions of affecting parameters on enzyme immobilization in both methods were found, and it was demonstrated that the highest activity yields of immobilized OPH onto epoxy and CDI treated cellulose were 68.32%and 73.51%, *** surface treatment of cellulose via covalent coupling with BTDE and CDI agents was proved by FTIr *** kinetic constants of the free and immobilized enzymes were determined, and it was showed that both immobilization techniques moderately increased the Kmvalue of the free *** improvements in storage and thermal stability were investigated and depicted that the half-life of immobilized OPH over the surface of epoxy modified cellulose had a better growth compared to the free and immobilized enzymes onto CDI treated ***, the pH stability of the immobilized preparations was enhanced relative to the free counterpart and revealed that all enzyme samples would have the same optimum pH value for stability at ***, the immobilized OPH onto epoxy and CDI activated cellulose retained about 59% and 68% of their initial activity after ten turns of batch operation, *** results demonstrated the high performance of OPH enzyme in immobilized state onto an inexpensive support with the potential of industrial applications.

关键词： Organophosphorus hydrolase Cellulose powder Activation Immobilization Stability

Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural regeneration research 2025年第3期20卷 803-804页

作者： Glenn A.Harris Lauren r.Hirschfeld rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3r) or 4-repeat(4r) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases

Analytical Modeling of a Multi-queue Nodes Network router

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International Journal of Automation and computing 2011年第4期8卷 459-464页

作者： Hussein Al-Bahadili jafar Ababneh Fadi Thabtah Faculty of Information Technology Petra University Amman Jordan Faculty of Information Technology and Sciences World Islamic Sciences and Education University Amman Jordan Faculty of Information Technology Philadelphia University Amman Jordan

This paper presents the derivation of an analytical model for a multi-queue nodes network router, which is referred to as the multi-queue nodes （mQN） model. In this model, expressions are derived to calculate two performance metrics, namely, the queue node and system utilization factors. In order to demonstrate the flexibility and effectiveness of the mQN model in analyzing the performance of an mQN network router, two scenarios are performed. These scenarios investigated the variation of queue nodes and system utilization factors against queue nodes dropping probability for various system sizes and packets arrival routing probabilities. The performed scenarios demonstrated that the mQN analytical model is more flexible and effective when compared with experimental tests and computer simulations in assessing the performance of an mQN network router.

关键词： Congested networks network routers active queue managements multi-queue nodes (mQN) systems analytical model- ing utilization factor.

Ether-IoT:A realtime Lightweight and Scalable Blockchain-Enabled Cache Algorithm for IoT Access Control

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Computers, Materials & Continua 2023年第5期75卷 3797-3815页

作者： Hafiz Adnan Hussain Zulkefli Mansor Zarina Shukur Uzma jafar Universiti Kebangsaan Malaysia Bangi43000Malaysia

Several unique characteristics of Internet of Things(IoT)devices,such as distributed deployment and limited storage,make it challenging for standard centralized access control systems to enable access control in today’s large-scale IoT *** solve these challenges,this study presents an IoT access control system called Ether-IoT based on the Ethereum Blockchain(BC)infrastructure with Attribute-Based Access Control(ABAC).Access Contract(AC),Cache Contract(CC),Device Contract(DC),and Policy Contract(PC)are the four central smart contracts(SCs)that are included in the proposed *** offers a way to save user characteristics in a local cache system to avoid delays during transactions between BC and IoT *** is the fundamental program users typically need to run to build an access control *** offers a means for storing the resource data created by devices and a method for querying that *** offers administrative settings to handle ABAC policies on users’***-IoT,combined with ABAC and the BC,enables IoT access control management that is decentralized,fine-grained and dynamically *** research gives a real-world case study to illustrate the suggested framework’s *** the end,a simulation experiment is performed to evaluate the system’s *** ensure data integrity in dispersed systems,the results show that Ether-IoT can sustain high throughput in contexts with a large number of requests.

关键词： Blockchain Internet of Things IoT access control ABAC Ethereum distributed system

An extended discrete particle swarm optimization algorithm for the dynamic facility layout problem

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 520-529页

作者： Hassan rEZAZADEH Mehdi GHAZANFArI Mohammad SAIDI-MEHrABAD Seyed jafar SADJADI Department of Industrial Engineering Iran University of Science and TechnologyNarmak Tehran Iran

We extended an improved version of the discrete particle swarm optimization (DPSO) algorithm proposed by Liao et al.(2007) to solve the dynamic facility layout problem (DFLP). A computational study was performed with the existing heuristic algorithms, including the dynamic programming (DP), genetic algorithm (GA), simulated annealing (SA), hybrid ant system (HAS), hybrid simulated annealing (SA-EG), hybrid genetic algorithms (NLGA and CONGA). The proposed DPSO algorithm, SA, HAS, GA, DP, SA-EG, NLGA, and CONGA obtained the best solutions for 33, 24, 20, 10, 12, 20, 5, and 2 of the 48 problems from (Balakrishnan and Cheng, 2000), respectively. These results show that the DPSO is very effective in dealing with the DFLP. The extended DPSO also has very good computational efficiency when the problem size increases.

关键词： Dynamic facility layout problem (DFLP) Particle swarm optimization (PSO) Optimization Heuristic method

Application of decision tree to selection of MTBM for adverse geological conditions

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International Journal of Mining Science and Technology 2013年第4期23卷 499-507页

作者： jafarimoghaddam Alireza Khademi Hamidi jafar Najaf Mohammad Member of Young researchers Club Islamic Azad University Mining Engineering Department Faculty of Engineering Tarbiat Modares University Department of Civil Engineering University of Texas at Arlington

So many potential risks can be identifed for application of trenchless technology especially using microtunneling *** changes in ground conditions,such as encountering boulders,tree roots,ground water and man-made structures such as old foundations are the principal geotechnical risks,which affect the selection of an appropriate microtunnel boring *** the other hand,the performance of each microtunneling technique will differ while encountering such ***,predicting the potential hazards provides a better safety and risk management *** this study,a couple of potentially hazardous situation,which are commonly associated with ground conditions,were identifed and investigated.A decision tree aid methodology was proposed based on geotechnical risk assessment for selection of proper microtunneling *** on the approach the most appropriate microtunneling technique has the minimum risk level either before or after hazards mitigation *** order to check the effciency of the approach in practice,selection of microtunnel boring machine for Hamadan sewerage pipeline project was ***,an earth pressure balance(EPB)MTBM was selected for the project.

关键词： Trenchless technology Microtunnel boring machine(MTBM) Diffcult ground conditions Geotechnical risk Decision tree

Multigene genetic programming for sediment transport modeling in sewers for conditions of non-deposition with a bed deposit

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International Journal of Sediment research 2018年第3期33卷 262-270页

作者： Mir jafar Sadegh Safari Ali Danandeh Mehr Department of Civil Engineering Urmia University Department of Civil Engineering University of Tabriz Department of Civil Engineering Antalya Bilim University

It is known that construction of large sewers based on consideration of flow with non-deposition without a bed deposit is not economical. Sewer design based on consideration of flow with nondeposition with a bed deposit reduces channel bed slope and construction cost in which the presence of a small depth of sediment deposition on the bed increases the sediment transport capacity of the *** paper suggests a new Pareto-optimal model developed by the multigene genetic programming(MGGP) technique to estimate particle Froude number(Frp) in large sewers with conditions of sediment deposition on the bed. To this end, four data sets including wide ranges of sediment size and concentration, deposit thickness, and pipe size are used. On the basis of different statistical performance indices, the efficiency of the proposed Pareto-optimal MGGP model is compared to those of the best MGGP model developed in the current study as well as the conventional regression models available in the literature. The results indicate the higher efficiency of the MGGP-based models for Frp estimation in the case of no additional deposition onto a bed with a sediment deposit. Inasmuch as the Pareto-optimal MGGP model utilizes a lower number of input parameters to yield comparatively higher performance than the conventional regression models, it can be used as a parsimonious model for self-cleansing design of large sewers in practice.

关键词： Bed load Bed deposition Non-deposition Multigene genetic programming Sediment transport Sewer