检索结果-内蒙古大学图书馆

QoE oriented intelligent online learning evaluation technology in B5G scenario

Digital communications and networks 2024年第1期10卷 7-15页

作者： Mingzi Chen Xin Wei Peizhong Xie Zhe Zhang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing210003China Institute of Higher Education Nanjing University of Posts and TelecommunicationsNanjing210003China

Students'demand for online learning has exploded during the post-COvID-19 pandemic ***,due to their poor learning experience,students'dropout rate and learning performance of online learning are not always *** technical advantages of Beyond Fifth Generation(B5G)can guarantee a good multimedia Quality of Experience(QoE).As a special case of multimedia services,online learning takes into account both the usability of the service and the cognitive development of the *** that affect the Quality of Online Learning Experience(OL-QoE)become more *** get over this dilemma,we propose a systematic scheme by integrating big data,Machine Learning(ML)technologies,and educational psychology ***,we first formulate a general definition of OL-QoE by data analysis and experimental *** formula considers both the subjective and objective factors(i.e.,video watching ratio and test scores)that most affect ***,we induce an extended layer to the classic Broad Learning System(BLS)to construct an Extended Broad Learning System(EBLS)for the students'OL-QoE *** the extended layer can increase the width of the BLS model and reduce the redundant nodes of BLS,the proposed EBLS can achieve a trade-off between the prediction accuracy and computation ***,we provide a series of early intervention suggestions for different types of students according to their predicted OL-QoE *** timely interventions,their OL-QoE and learning performance can be *** results verify the effectiveness oftheproposed scheme.

关键词： B5G Online learning Quality of experience

来源：评论

学校读者我要写书评

暂无评论

Enhanced photoelectrochemical performance of ZnO/α-Fe2O3 heterojunction photoelectrode fabricated by facile hydrothermal and spin-coating method

引用

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2024年 51卷 633-642页

作者： Zhang, Ruiliang Zhao, Gaoman Hu, Jun Lu, Pei Liu, Shengli Li, Xiaobing Hebei Normal Univ Hebei Prov Innovat Ctr Wireless Sensor Network Dat Hebei Prov Key Lab Informat Fus & Intelligent Cont Shijiazhuang 050024 Hebei Peoples R China

The present study reports the successful fabrication of ZnO/alpha-Fe2O3 heterojunctions by facile and simple hydrothermal and spin-coating methods. The effect of spin-coating different FeCl3 precursor layers on the photo electrochemical performance has been investigated. Additionally, the procedure of spin-coating FeCl3 precursors was simulated by fluent software. It is noteworthy that ZnO/alpha-Fe2O3 heterojunctions increase the absorption of visible light, promote the separation and transfer of photogenerated charge carriers, reduce the interfacial resistance between the photoelectrode and electrolyte, and provide a larger electrochemically active contact area in contrast to pure ZnO nanorods. The highest photocurrent density and the highest IPCE (incident photon-to current efficiency) reach 1.82 mA cm-2 and 40 % respectively when spin-coating three layers. Moreover, the mechanism of enhanced PEC performance was further discussed via EIS (electrochemical impedance spectroscopy), Mott-Schottky curves, Energy band structure diagram, and the electrochemical active surface area (ECSA) test.

关键词： ZnO nanorods PEC performance Fluent simulation Photo-corrosion

来源：评论

学校读者我要写书评

暂无评论

A teacher-student based attention network for fine-grainedimage recognition

引用

Digital communications and networks 2025年第1期11卷 52-59页

作者： Ang Li Xueyi Zhang Peilin Li Bin Kang Key Laboratory of Broadband Wireless Communication and Sensor Network Technology(Ministry of Education) Nanjing University of Posts and TelecommunicationsNanjing210003China School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China

Fine-grained Image Recognition(FGIR)task is dedicated to distinguishing similar sub-categories that belong to the same super-category,such as bird species and car *** order to highlight visual differences,existing FGIR works often follow two steps:discriminative sub-region localization and local feature ***,these works pay less attention on global context *** neglect a fact that the subtle visual difference in challenging scenarios can be highlighted through exploiting the spatial relationship among different subregions from a global view ***,in this paper,we consider both global and local information for FGIR,and propose a collaborative teacher-student strategy to reinforce and unity the two types of *** framework is implemented mainly by convolutional neural network,referred to Teacher-Student Based Attention Convolutional Neural network(T-S-ACNN).For fine-grained local information,we choose the classic Multi-Attention network(MA-Net)as our baseline,and propose a type of boundary constraint to further reduce background noises in the local attention *** this way,the discriminative sub-regions tend to appear in the area occupied by fine-grained objects,leading to more accurate sub-region *** fine-grained global information,we design a graph convolution based Global Attention network(GA-Net),which can combine extracted local attention maps from MA-Net with non-local techniques to explore spatial relationship among *** last,we develop a collaborative teacher-student strategy to adaptively determine the attended roles and optimization modes,so as to enhance the cooperative reinforcement of MA-Net and *** experiments on CUB-200-2011,Stanford Cars and FGVC Aircraft datasets illustrate the promising performance of our framework.

关键词： Fine-grained image recognition Collaborative teacher-student strategy Multi-attention Global attention

来源：评论

学校读者我要写书评

暂无评论

Task Offloading With Service Migration for Satellite Edge Computing: A Deep Reinforcement Learning Approach

引用

IEEE ACCESS 2024年 12卷 25844-25856页

作者： Wu, Haonan Yang, Xiumei Bu, Zhiyong Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai 200050 Peoples R China Chinese Acad Sci Key Lab Wireless Sensor Network & Commun Shanghai 200050 Peoples R China

Satellite networks with edge computing servers promise to provide ubiquitous and low-latency computing services for the Internet of Things (IoT) applications in the future satellite-terrestrial integrated network (STIN). For some emerging IoT applications, the services require real-time user-dependent state information, such as time-varying task states and user-specific configurations, to maintain service continuity. Service migration is crucial for dynamic task offloading to synchronize the user-dependent state information between computing servers. However, how to offload computing tasks at low latency with the impact of service migration remains challenging due to the high-speed movement and load imbalance of low Earth orbit (LEO) satellite networks. In this work, we investigate the task offloading problem with service migration for satellite edge computing (SEC) using inter-satellite cooperation. Facing dynamic service requirements with limited on-board bandwidth, energy, and storage resources of satellite networks, we formulate the problem with the aim of minimizing the service delay to optimize the offloading path selection. By leveraging a deep reinforcement learning (DRL) approach, we propose a distributed scheme based on the Dueling-Double-Deep-Q-Learning (D3QN) algorithm. Simulation results show that the proposed scheme can effectively reduce the service delay, and outperform the benchmark algorithms.

关键词： Satellites Task analysis Low earth orbit satellites Delays Servers Internet of Things Low latency communication Edge computing Deep reinforcement learning Satellite edge computing (SEC) task offloading service migration deep reinforcement learning (DRL)

来源：评论

学校读者我要写书评

暂无评论

Dual Radial-Resonant Wide Beamwidth Circular Sector Microstrip Patch Antennas

引用

Chinese Journal of Electronics 2023年第4期32卷 710-719页

作者： MAO Xiaohui LU Wenjun JI Feiyan XING Xiuqiong ZHU Lei Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Department of Electrical and Computer Engineering Faculty of Science and Technology University of Macau

In this article, a design approach to a radial-resonant wide beamwidth circular sector patch antenna is advanced. As properly evolved from a U-shaped d ipole, a prototype magnetic dipole can be fit in the radial direction of a circular sector patch radiator, with its length set as the positive odd-integer multiples of onequarter wavelength. In this way, multiple TM0m（m = 1,2,...） modes resonant circular sector patch antenna with short-circuited circumference and widened E-plane beamwidth can be realized by proper excitation and perturbations. Prototype antennas are then designed and fabricated to validate the design approach. Experimental results reveal that the E-plane beamwidth of a dual-resonant antenna fabricated on air/Teflon substrate can be effectively broadened to 128°/120°, with an impedance bandwidth of 17.4%/7.1%, respectively. In both cases, the antenna heights are strictly limited to no more than 0.03-guided wavelength. It is evidently validated that the proposed approach can effectively enhance the operational bandwidth and beamwidth of a microstrip patch antenna while maintaining its inherent low profile merit.

关键词： Geometry Patch antennas Perturbation methods Prototypes Magnetic resonance Microstrip antennas Bandwidth

来源：评论

学校读者我要写书评

暂无评论

Equivalent Bandwidth Concept and Its Usage in the network Selection

引用

China communications 2025年第2期22卷 213-225页

作者： Ma Anhua Pan Su Zhou Weiwei Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and TelecommunicationsNanjing 210003China

Maximize the resource utilization efficiency and guarantee the quality of service(QoS)of users by selecting the network are the key issues for heterogeneous network operators,but the resources occupied by users in different networks cannot be compared *** paper proposes a network selection algorithm for heterogeneous ***,the concept of equivalent bandwidth is proposed,through which the actual resources occupied by users with certain QoS requirements in different networks can be compared *** the concept of network applicability is defined to express the abilities of networks to support different *** proposed network selection algorithm first evaluates whether the network has enough equivalent bandwidth required by the user and then prioritizes network with poor applicability to avoid the situation that there are still residual resources in entire network,but advanced services can not be *** simulation results show that the proposed algorithm obtained better performance than the baselines in terms of reducing call blocking probability and improving network resource utilization efficiency.

关键词： call blocking probability equivalent bandwidth heterogeneous network network applicability

来源：评论

学校读者我要写书评

暂无评论

Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter Communication System

引用

China communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang Ting Li Yin Lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

来源：评论

学校读者我要写书评

暂无评论

Quality-Aware Massive Content Delivery in Digital Twin-Enabled Edge networks

引用

China communications 2023年第2期20卷 1-13页

作者： Yun Gao Junqi Liao Xin Wei Liang Zhou School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China

Massive content delivery will become one of the most prominent tasks of future B5G/6G ***,various multimedia applications possess huge differences in terms of object oriented(i.e.,machine or user)and corresponding quality evaluation metric,which will significantly impact the design of encoding or decoding within content delivery *** get over this dilemma,we firstly integrate the digital twin into the edge networks to accurately and timely capture Quality-of-Decision(QoD)or Quality-of-Experience(QoE)for the guidance of content ***,in terms of machinecentric communication,a QoD-driven compression mechanism is designed for video analytics via temporally lightweight frame classification and spatially uneven quality assignment,which can achieve a balance among decision-making,delivered content,and encoding ***,in terms of user-centric communication,by fully leveraging haptic physical properties and semantic correlations of heterogeneous streams,we develop a QoE-driven video enhancement scheme to supply high data *** results demonstrate the remarkable performance improvement of massive content delivery.

关键词： content delivery digital twin edge networks QoD QoE

来源：评论

学校读者我要写书评

暂无评论

A novel analog circuit fault diagnosis method based on multi-channel 1D-resnet and wavelet packet transform

引用

ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING 2024年第1-3期121卷 25-38页

作者： Zhou, Xin Tang, Xuanzhong Liang, Wenhai Sichuan Normal Univ Coll Phys & Elect Engn Chengdu 610101 Sichuan Peoples R China Sichuan Normal Univ Key Lab Wireless Sensor Network Univ Sichuan Prov Chengdu 610101 Sichuan Peoples R China

To quickly and accurately locate the fault location and fault parameter deviation of analog circuits, a novel incipient fault diagnosis method based on multi-channel one-dimensional residual networks (MC-1D-ResNet) and wavelet packet transform(WPT) is proposed in this paper. The WPT is employed to preprocess the time-domain response signals of analog circuit, and the proposed MC-1D-ResNet is utilized for feature mining and fault *** two-level WPT is first carried out on the time-domain response signal to generate one approximate signal and three detailed signals. Secondly, MC-1D-ResNet further performs feature mining on approximate signals and three detailed signals, and realizes fault diagnosis. Through simulation analysis, the proposed method is fully evaluated with the Sallen-key bandpass filter circuit and the four-op-amp biquad high-pass filter circuit. Even in complex Four-op-amp biquad high-pass filtering circuits, the diagnostic accuracy can reach 99.74%. This article also designs a hardware testing platform based on FPGA, and conduct actual fault diagnosis tests on the four-op-amp biquad high-pass filter circuit. The results show that the average accuracy of 50 actual diagnoses for each type of fault in the circuit was 97.80%.

关键词： Fault diagnosis Multi-channel 1D-ResNet Analog circuit Wavelet packet transform

来源：评论

学校读者我要写书评

暂无评论

Achieving the Optimum Rate for Cross-Modal Source Coding

引用

IEEE TRANSACTIONS ON MULTIMEDIA 2024年 26卷 9722-9735页

作者： Yuan, Zhe Wu, Dan Zhou, Liang Nanjing Univ Posts & Telecommun Key Lab Broadband Wireless Commun & Sensor Network Minist Educ Nanjing 210003 Peoples R China Army Engn Univ PLA Coll Commun Engn Nanjing 210007 Peoples R China

Multi-modal applications are expected to dominate in the 5G and B5G era. However, traditional source coding methods are not efficient or reliable due to neglecting semantic redundancy and mutual influences between different modalities' sources. To address this, cross-modal source coding (CMSC) has been proposed as a promising solution. However, there are still two main challenges: determining the optimum rate of CMSC considering delay and reliability constraints, and designing a practical CMSC near the optimum rate. To tackle these challenges, this paper focuses on studying the optimum source coding rate of CMSC and its practical implementation. On the theoretical side, an (n, epsilon)-achievable rate region is derived, representing the source coding rates subject to a fixed blocklength n and the target error probability e . Additionally, the optimum source coding rate can be approximated by calculating the infimum of the (n, epsilon)- achievable rate region with a rate dispersion function. On the technical side, a general implementation for CMSC is proposed, which fully leveraging channel coding and artificial intelligence (AI) semantic analysis to achieve the optimum rate. Numerical results demonstrate that CMSC can obtain 50% improvement in theory and 37.5% enhancement in practice against the baseline model abstracted from traditional schemes when multi-modal sources are semantically correlated.

关键词： Semantics Source coding Haptic interfaces Reliability Streams Redundancy Decoding Cross-modal source coding semantic relevance achievable rate region optimum rate video and haptic coding

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：