检索结果-南通市图书馆

Energy efficiency aware dynamic rate and power adaptation in carrier sensing based WLANs under Rayleigh fading and shadowing

引用

Digital Communications and Networks 2024年第4期10卷 918-933页

作者： md.forkan uddin Department of Electrical and Electronic Engineering Bangladesh University of Engineering and TechnologyDhaka1205Bangladesh

We consider the problem of energy efficiency aware dynamic adaptation of data transmission rate and transmission power of the users in carrier sensing based Wireless Local Area Networks(WLANs)in the presence of path loss,Rayleigh fading and log-normal *** a data packet transmission,we formulate an optimization problem,solve the problem,and propose a rate and transmission power adaptation scheme with a restriction methodology of data packet transmission for achieving the optimal energy *** the restriction methodology of data packet transmission,a user does not transmit a data packet if the instantaneous channel gain of the user is lower than a *** evaluate the performance of the proposed scheme,we develop analytical models for computing the throughput and energy efficiency of WLANs under the proposed scheme considering a saturation traffic *** then validate the analytical models via *** find that the proposed scheme provides better throughput and energy efficiency with acceptable throughput fairness if the restriction methodology of data packet transmission is *** means of the analytical models and simulations,we demonstrate that the proposed scheme provides significantly higher throughput,energy efficiency and fairness index than a traditional non-adaptive scheme and an existing most relevant adaptive *** and energy efficiency gains obtained by the proposed scheme with respect to the existing adapting scheme are about 75%and 103%,respectively,for a fairness index of *** also study the effect of various system parameters on throughput and energy efficiency and provide various engineering insights.

关键词： Carrier sense multiple access Energy efficiency Fading and shadowing Rate and power adaptation Throughput Wireless local area networks

来源：

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

Steel Surface Defect Detection Using Learnable Memory Vision Transformer

引用

Computers, Materials & Continua 2025年第1期82卷 499-520页

作者： Syed Tasnimul Karim Ayon Farhan md.Siraj Jia uddin Department of Computer Science and Engineering BRAC UniversityDhaka1212Bangladesh Department of AI and Big Data Endicott CollegeWoosong UniversityDaejeon34606Republic of Korea

This study investigates the application of Learnable Memory Vision Transformers(LMViT)for detecting metal surface flaws,comparing their performance with traditional CNNs,specifically ResNet18 and ResNet50,as well as other transformer-based models including Token to Token ViT,ViT withoutmemory,and Parallel *** awidely-used steel surface defect dataset,the research applies data augmentation and t-distributed stochastic neighbor embedding(t-SNE)to enhance feature extraction and *** techniques mitigated overfitting,stabilized training,and improved generalization *** LMViT model achieved a test accuracy of 97.22%,significantly outperforming ResNet18(88.89%)and ResNet50(88.90%),aswell as the Token to TokenViT(88.46%),ViT without memory(87.18),and Parallel ViT(91.03%).Furthermore,LMViT exhibited superior training and validation performance,attaining a validation accuracy of 98.2%compared to 91.0%for ResNet 18,96.0%for ResNet50,and 89.12%,87.51%,and 91.21%for Token to Token ViT,ViT without memory,and Parallel ViT,*** findings highlight the LMViT’s ability to capture long-range dependencies in images,an areawhere CNNs struggle due to their reliance on local receptive fields and hierarchical feature *** additional transformer-based models also demonstrate improved performance in capturing complex features over CNNs,with LMViT excelling particularly at detecting subtle and complex defects,which is critical for maintaining product quality and operational efficiency in industrial *** instance,the LMViT model successfully identified fine scratches and minor surface irregularities that CNNs often *** study not only demonstrates LMViT’s potential for real-world defect detection but also underscores the promise of other transformer-based architectures like Token to Token ViT,ViT without memory,and Parallel ViT in industrial scenarios where complex spatial relationships are *** research m

关键词： Learnable Memory Vision Transformer(LMViT) Convolutional Neural Networks(CNN) metal surface defect detection deep learning,computer vision image classification learnable memory gradient clipping label smoothing t-SNE visualization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Status and prospects for symmetric organic redox flow batteries

引用

Journal of Energy Chemistry 2025年第1期100卷 125-143页

作者： md Al Raihan C.Adam Dyker Department of Chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Regeneration mechanisms and therapeutic strategies for neuromuscular junctions in aging and diseases

引用

Neural Regeneration Research 2025年第1期20卷 193-194页

作者： Masashi Fujitani Abu md Mamun Tarif Yoshinori Otani Department of Anatomy and Neuroscience Faculty of MedicineShimane UniversityShimaneJapan

The neuromuscular junction(NMJ)is an essential synaptic structure composed of motor neurons,skeletal muscles,and glial cells that orchestrate the critical process of muscle contraction(Li et al.,2018).The typical NMJ structure is classically described as having a“pretzel-like”shape in mice(Figure 1),whereas human NMJs have a smaller,fragmented structure throughout *** NMJs exhibit smaller or fragmented endplates,partial denervation,reduced numbers of synaptic vesicles,abnormal presynaptic mitochondria,and dysfunctional perisynaptic Schwann cells(Alhindi et al.,2022).

关键词： aging structure Figure

来源：

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

Ru/NiMnB spherical cluster pillar for highly proficient green hydrogen electrocatalyst at high current density

引用

Journal of Energy Chemistry 2025年第1期100卷 397-408页

作者： md Ahasan Habib Shusen Lin Mehedi Hasan Joni Sumiya Akter Dristy Rutuja Mandavkar Jae-Hun Jeong Jihoon Lee Department of Electronic Engineering College of Electronics and Information Kwangwoon University

Advanced OER/HER electrocatalytic alternatives are crucial for the wide adaptation of green hydrogen ***,Ru/NiMnB spherical cluster pillar （SCP）,denoted as Ru/NiMnB,is synthesized using a combination of electro-deposition and hydrothermal *** investigation of Ru doping in the NiMnB matrix revealed significant improvements in electrocatalytic *** Ru/NiMnB SCPs demonstrate superior OER/HER activity with low overpotentials of 150 and 103 mV at 50mA/cm2in 1 M KOH,making them highly competitive with state-of-the-art ***,the Ru/NiMnB SCPs exhibit a low 2-E cell voltage of 2.80 V at ultra-high current density of 2,000 m A/cm2in 1 M KOH,outperforming the standard benchmark electrodes of RuO2||Pt/C,thereby positioning Ru/NiMnB as one of the best bifunctional *** SCPs exhibit exceptional high-current characteristics,stability and corrosion resistance,as evidenced by continuous operation at 1,000 mA/cm2high-current density for over 150 h in 6 M KOH at elevated temperatures under harsh industrial *** a small amount of Ru incorporation significantly enhances the electrocatalytic performances of NiMnB,attributed to increased active sites and improved intrinsic properties such as conductivity,adsorption/desorption capability and reaction ***,Ru/NiMnB SCPs present a promising bi-functional electrode concept for efficient green H2production.

关键词： Potassium hydroxide

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Reduction and pH-responsive performance of nitroxide radical-containing copolymers probed by EPR spectroscopy Dedicated to Professor Chaohui Ye on the occasion of his 80th birthday

引用

Magnetic Resonance Letters 2022年第4期2卷 255-265页

作者： md Alim uddin Haojie Yu Li Wang State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China

Although stimuli-responsive polymers have appeared as promising materials for drug administration,the effectiveness of these materials on various bioinspired stimuli is still open for *** this work,the stimuli-responsive behaviors of radical-containing nonamphiphilic copolymers were investigated using electron paramagnetic resonance(EPR)spectroscopy while altering the pH and reductant *** concentration of radicals in the aqueous solution had a considerable impact on *** nitroxide radicals(hydrophobic)were converted to hydroxylamine(hydrophilic)when ascorbic acid(Asc)was added as a reductant,and the assemblies were switched to dissolution with a rate control *** behavior of morphological change was observed in the acidic pH due to the disproportionation reaction of nitroxide radicals forming cationic *** acquired results give new insights into the colloidal nanoparticles of nonamphiphilic copolymers and encourage the development of comparable responsive nanoparticles with intriguing drug delivery applications.

关键词： Nonamphiphilic Nanoparticles Stimuli-responsive Self-assembly Electron paramagnetic resonance

来源：

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

Spatiotemporal variability of channel and bar morphodynamics in the Gorai-Madhumati River,Bangladesh using remote sensing and GIS techniques

引用

Frontiers of Earth Science 2020年第4期14卷 828-841页

作者： md.Yousuf Gazi Farhad Hossain Sumiya Sadeak md.Mahin uddin Department of Geology University of DhakaDhaka1000Bangladesh Department of Geography and Environment University of DhakaDhaka1000Bangladesh

Bangladesh is a riparian country that is criss-crossed by the many tributaries and distributaries of the mighty Ganges,Brahmaputra,and Meghna river ***-Madhumati,a distributary of the Ganges River is an example where morphological development of the river is associated with frequent channel shifting within the catchment *** main objective of this research is to quantify the extent of channel migration,erosion-accretion,river width,sinuosity,and charland morpho-dynamics from 1972 to 2018 using geospatial techniques combined with satellite images and hydrological *** study also addressed the impacts of Farakka Barrage construction in India on the shifting,flow behavior,and siltation of Gorai-Madhumati *** study shows that bar surface areas have abnormally increased in both segments after 1975 due to the construction of Farakka *** flow in the Gorai-Madhumati has dropped remarkably in the downstream and instigated huge sedimentation in this *** of the time series satellite images revealed that the morphology of the river channel experienced huge changes simultaneously with the changes in the seasonal flow and sedimentation all over the study *** trend has frequently shifted and taken place in the NW and NE direction in the observed sections of the *** the study period,total amount of accretion was greater than the net percentage of erosion on both banks of the *** discharge,bar accretion,and erosion history show that the Gorai-Madhumati River will no longer exist with the present flowing condition without attention and proper river management.

关键词： channel migration erosion-accretion morphodynamics geospatial techniques Gorai-Madhumati Bangladesh

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Fractional order prey-predator model incorporating immigration on prey:Complexity analysis and its control

引用

International Journal of Biomathematics 2024年第5期17卷 285-317页

作者： md.Jasim uddin Chandra Nath Podder Departmentof Mathematics University of Dhaka Dhaka-1000Bangladesh

In this paper,the Caputo fractional derivative is assumed to be the prey-predator *** order to create Caputo fractional differential equations for the prey-predator model,a discretization process is first *** fixed points of the model are categorized *** identify requirements for the fixed points of the suggested prey-predator model's local asymptotic *** demonstrate analytically that,under specific parametric conditions,a fractional order prey-predator model supports both a Neimark-Sacker(NS)bifurcation and a Flip *** present evidence for NS and Flip bifurcations using central manifold and bifurcation *** parameter values and the initial conditions have been found to have a profound impact on the dynamical behavior of the fractional order prey-predator *** the bifurcation parameter is increased,the system displays chaotic *** simulations are shown to demonstrate chaotic behaviors like bifurcations,phase portraits,invariant closed cycles,and attractive chaotic sets in addition to validating analytical *** suggested prey-predator dynamical system's chaotic behavior will be controlled by the OGY and hybrid control methodology,which will also visualize the chaotic state for various biological parameters.

关键词： Prey-predator model Caputo fractional derivative Flip and Neimark-Sacker(NS)bifurcations immigration chaos control numerical simulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Flow and erosion at a bend in the braided Jamuna River

引用

International Journal of Sediment Research 2012年第4期27卷 498-509页

作者： Mohammad Nazim uddin md.Munsur RAHMAN Department of Civil Engineering Dhaka University of Engineering and Technology Institute of Water and Flood Management Bangladesh University of Engineering and Technology

The braided Jamuna River frequently changes its *** the secondary channel in a braided river acts as a single thread meandering *** the present study an attempt has been made to investigate the flow patterns and to estimate the rate of bank erosion in a bend along the Jamuna *** three dimensional(3D) flow velocities were measured using Acoustic Doppler Current Profiler(ADCP).It is found that the near bank velocity is amplified by 1.1 to 1.3 times as compared with the section averaged velocity.A dominant secondary current is found in the upstream *** evolution as well as decay of the secondary current is not as clear as it is found in the laboratory *** is revealed from the analysis of the flow process that the causes of higher rate of erosion at the study bend are the oblique flow near bankline,six times amplified shear velocity than critical shear velocity near bankline and the secondary current which acts as a sediment transporting agent from the outer bank towards the inner bank or the sand *** on the flow processes,a simplified erosion prediction model is developed and applied to estimate the rate of erosion at a selected *** the predicted results have been compared with the observed data at the bend and all the available data at other bends along the Jamuna River.

关键词： Braided Jamuna River Bend Flow pattern Erosion prediction model

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Numerical solution of thermo-solutal mixed convective slip flow from a radiative plate with convective boundary condition

引用

Journal of Hydrodynamics 2016年第3期28卷 451-461页

作者： m.j.uddin o.anwar bég m.n.uddin a.i.md.ismail Department of Mathematics American International University-BangladeshDhakaBangladesh Fluid Mechanics Spray Research GroupPetroleum and Gas Engineering DivisionRoom G77Newton BuildingSchool of ComputingScience and Engineering(CSE)University of SalfordM54WTUK Department of Mathematical Sciences Ball State University2000 W University AvenueMuncieIN 47306USA School of Mathematical Sciences Universiti Sains MalaysiaPenang 11800Malaysia

A mathematical model for mixed convective slip flow with heat and mass transfer in the presence of thermal radiation is presented. A convective boundary condition is included and slip is simulated via the hydrodynamic slip parameter. Heat generation and absorption effects are also incorporated. The Rosseland diffusion flux model is employed. The governing partial differential conservation equations are reduced to a system of coupled, ordinary differential equations via Lie group theory method. The resulting coupled equations are solved using shooting method. The influences of the emerging parameters on dimensionless velocity, tempera- ture and concentration distributions are investigated. Increasing radiative-conductive parameter accelerates the boundary layer flow and increases temperature whereas it depresses concentration. An elevation in convection-conduction parameter also accelerates the flow and temperatures whereas it reduces concentrations. Velocity near the wall is considerably boosted with increasing momentum slip parameter although both temperature and concentration boundary layer thicknesses are decreased. The presence of a heat source is found to increase momentum and thermal boundary layer thicknesses but reduces concentration boundary layer thickness. Excelle- nt correlation of the numerical solutions with previous non-slip studies is demonstrated. The current study has applications in bio- reactor diffusion flows and high-temperature chemical materials processing systems.

关键词： slip flow thermal radiation lie group theory heat source/sink materials processing

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：