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Comparing the Accuracy of Network Utilization Performance between Real Network and Simulation Model for Local Area Network (LAN)
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作者 Mohd Nazri ISMAIL Abdullah Mohd ZIN 《International Journal of Communications, Network and System Sciences》 2008年第4期339-349,共11页
This article presents a novel approach for the measurement and estimation of network traffic utilization between network nodes in heterogeneous environment. This research investigates performance evaluation of network... This article presents a novel approach for the measurement and estimation of network traffic utilization between network nodes in heterogeneous environment. This research investigates performance evaluation of network interface on heterogeneous services and technologies environment. This study proposes an enhanced equation to evaluate the performance of network interface via Little Law and Queuing theories to improve the evaluation algorithm. To get accuracy results on the performance of simulation model, it measures (verify and validate) data from Local Area Network (real network environment). This project uses network management tool to capture those data and Fluke Optiview device to generate traffic. As a result, this simulation model can provide a good approximation of the real traffic observed in the real network environment. Through laboratory and field experiments, the result shows that the model via simulation is capable of approximating the performance of network utilization and traffic over heterogeneous services and techniques within a minimum error range. 展开更多
关键词 network UTILIZATION real network LAN
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Design, Analysis and Real-time Implementation of Networked Predictive Control Systems 被引量:6
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作者 LIU Guo-Ping SUN Jian ZHAO Yun-Bo 《自动化学报》 EI CSCD 北大核心 2013年第11期1769-1777,共9页
这份报纸用预兆的控制策略涉及设计,分析和联网的控制系统的即时实现。联网的控制系统的特征的分析被详细说明,它证明一个联网的控制系统与常规控制系统不同。完成靠近环的联网的控制系统的需要的性能,联网的预兆的控制计划被介绍。... 这份报纸用预兆的控制策略涉及设计,分析和联网的控制系统的即时实现。联网的控制系统的特征的分析被详细说明,它证明一个联网的控制系统与常规控制系统不同。完成靠近环的联网的控制系统的需要的性能,联网的预兆的控制计划被介绍。设计,稳定性分析和联网的预兆的控制系统的即时实现被学习。它被联网的预兆的控制计划能补偿随机的网络通讯延期和数据退学学生的模拟和实际实验说明,完成需要的控制性能并且有好靠近环的稳定性。 展开更多
关键词 闭环网络控制系统 预测控制系统 实时实现 设计 预测控制策略 控制方案 网络预测 控制性能
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A Real-Time TCP Stream Reassembly Mechanism in High-Speed Network 被引量:3
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作者 熊兵 陈晓苏 陈宁 《Journal of Southwest Jiaotong University(English Edition)》 2009年第3期185-191,共7页
With the continual growth of the variety and complexity of network crime means, the traditional packet feature matching cannot detect all kinds of intrusion behaviors completely. It is urgent to reassemble network str... With the continual growth of the variety and complexity of network crime means, the traditional packet feature matching cannot detect all kinds of intrusion behaviors completely. It is urgent to reassemble network stream to perform packet processing at a semantic level above the network layer. This paper presents an efficient TCP stream reassembly mechanism for real-time processing of high-speed network traffic. By analyzing the characteristics of network stream in high-speed network and TCP connection establishment process, several polices for designing the reassembly mechanism are built. Then, the reassembly implementation is elaborated in accordance with the policies. Finally, the reassembly mechanism is compared with the traditional reassembly mechanism by the network traffic captured in a typical gigabit gateway. Experiment results illustrate that the reassembly mechanism is efficient and can satisfy the real-time property requirement of traffic analysis system in high-speed network. 展开更多
关键词 TCP stream reassembly High-speed network real-time property Reassembly policy
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Real estate appraisal system based on GIS and BP neural network 被引量:12
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作者 LIU Xiao-sheng1, DENG Zhe1, WANG Ting-li2 1. School of Architecture and Survey Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China 2. School of Applied Science, Jiangxi University of Science and Technology, Ganzhou 341000, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期626-630,共5页
For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was desi... For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2008. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system. 展开更多
关键词 BP neural network GIS HEDONIC PRICE real ESTATE APPRAISAL
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Modeling and Statistical Properties Research on Online Real-Time Information Transmission Network 被引量:2
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作者 Guangming Deng Zhen Jia 《Open Journal of Applied Sciences》 2014年第5期234-241,共8页
In this paper, the model of the online real-time information transmission network, such as wechat, micro-blog, and QQ network, is proposed and built, based on the connection properties between users of the online real... In this paper, the model of the online real-time information transmission network, such as wechat, micro-blog, and QQ network, is proposed and built, based on the connection properties between users of the online real-time information transmission network, and combined with the local world evolving characteristics in complex network, then the statistical topological properties of the network is obtained by numerical simulation. Furthermore, we simulated the process of information transmission on the network, according to the actual characteristics of the online real-time information transmission. Statistics show that the degree distribution presents the characteristics of scale free network, presenting power law distribution, while the average path length, the average clustering coefficient and the average size of the network also has a power-law relationship, moreover, the model parameters has no effect on power-law exponent. The spread of information on the network represents obvious fluctuation scaling, reflecting the characteristics that information transmission fluctuates over time. 展开更多
关键词 network INFORMATION TRANSMISSION real-TIME INFORMATION FLUCTUATION SCALING
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Verification of Real-Time Pricing Systems Based on Probabilistic Boolean Networks
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作者 Koichi Kobayashi Kunihiko Hiraishi 《Applied Mathematics》 2016年第15期1734-1747,共15页
In this paper, verification of real-time pricing systems of electricity is considered using a probabilistic Boolean network (PBN). In real-time pricing systems, electricity conservation is achieved by manipulating the... In this paper, verification of real-time pricing systems of electricity is considered using a probabilistic Boolean network (PBN). In real-time pricing systems, electricity conservation is achieved by manipulating the electricity price at each time. A PBN is widely used as a model of complex systems, and is appropriate as a model of real-time pricing systems. Using the PBN-based model, real-time pricing systems can be quantitatively analyzed. In this paper, we propose a verification method of real-time pricing systems using the PBN-based model and the probabilistic model checker PRISM. First, the PBN-based model is derived. Next, the reachability problem, which is one of the typical verification problems, is formulated, and a solution method is derived. Finally, the effectiveness of the proposed method is presented by a numerical example. 展开更多
关键词 Model Checking Probabilistic Boolean networks real-Time Pricing
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Evolution analysis of a UAV real-time operating system from a network perspective 被引量:4
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作者 Zheng ZHENG Guanping XIAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第1期176-185,共10页
With the flourishing development of Unmanned Aerial Vehicles(UAVs), the mission tasks of UAVs have become more and more complex. Consequently, a Real-Time Operating System(RTOS) that provides operating environments fo... With the flourishing development of Unmanned Aerial Vehicles(UAVs), the mission tasks of UAVs have become more and more complex. Consequently, a Real-Time Operating System(RTOS) that provides operating environments for various mission services on these UAVs has become crucial, which leads to the necessity of having a deep understanding of an RTOS. In this paper, an empirical study is conducted on FreeRTOS, a commonly used RTOS for UAVs, from a complex network perspective. A total of 85 releases of FreeRTOS, from V2.4.2 to V10.0.0, are modeled as directed networks, in which the nodes represent functions and the edges denote function calls. It is found that the size of the FreeRTOS network has grown almost linearly with the evolution of the versions, while its main core has evolved steadily. In addition, a k-core analysis-based metric is proposed to identify major functionality changes of FreeRTOS during its evolution.The result shows that the identified versions are consistent with the version change logs. Finally,it is found that the clustering coefficient of the Linux OS scheduler is larger than that of the FreeRTOS scheduler. In conclusion, the empirical results provide useful guidance for developers and users of UAV RTOSs. 展开更多
关键词 Complex networks EVOLUTION FREERTOS k-core DECOMPOSITION real-TIME operating system
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Influences of Network Delay on Quality of Experience for Soft Objects in Networked Real-Time Game with Haptic Sense
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作者 Mya Sithu Yutaka Ishibashi +1 位作者 Pingguo Huang Norishige Fukushima 《International Journal of Communications, Network and System Sciences》 2015年第11期440-445,共6页
In this paper, we investigate the influences of network delay on QoE (Quality of Experience) such as the operability of haptic interface device and the fairness between players for soft objects in a networked real-tim... In this paper, we investigate the influences of network delay on QoE (Quality of Experience) such as the operability of haptic interface device and the fairness between players for soft objects in a networked real-time game subjectively and objectively. We handle a networked balloon bursting game in which two players burst balloons (i.e., soft objects) in a 3D virtual space by using haptic interface devices, and the players compete for the number of burst balloons. As a result, we find that the operability depends on the network delay from the local terminal to the other terminal, and the fairness is mainly dependent on the difference in network delay between the players’ terminals. We confirm that there exists a trade-off relationship between the operability and the fairness. We also see that the contribution of the fairness is larger than that of the operability to the comprehensive quality (i.e., the weighted sum of the operability and fairness). Assessment results further show that the output timing of terminals should be adjusted to the terminal which has the latest output timing to maintain the fairness when the difference in network delay between the terminals is large. In this way, the comprehensive quality at each terminal can be maintained as high as possible. 展开更多
关键词 networkED real-TIME GAME Virtual Environment Balloon BURSTING GAME HAPTIC Interface Devices network Delay Quality of Experience OPERABILITY Fairness
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Contention-Based Beaconless Real-Time Routing Protocol for Wireless Sensor Networks
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作者 Chao Huang Guoli Wang 《Wireless Sensor Network》 2010年第7期528-537,共10页
This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at ... This paper presents a novel real-time routing protocol, called CBRR, with less energy consumption for wireless sensor networks (WSNs). End-to-End real-time requirements are fulfilled with speed or delay constraint at each hop through integrating the contention and neighbor table mechanisms. More precisely, CBRR maintains a neighbor table via the contention mechanism being dependent on wireless broadcast instead of beacons. Comprehensive simulations show that CBRR can not only achieve higher performance in static networks, but also work well for dynamic networks. 展开更多
关键词 Wireless Sensor network real-TIME Routing Protocol Contention-Based Scheme Beaconless
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Multistability of delayed complex-valued recurrent neural networks with discontinuous real-imaginarytype activation functions
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作者 黄玉娇 胡海根 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期271-279,共9页
In this paper, the multistability issue is discussed for delayed complex-valued recurrent neural networks with discontinuous real-imaginary-type activation functions. Based on a fixed theorem and stability definition,... In this paper, the multistability issue is discussed for delayed complex-valued recurrent neural networks with discontinuous real-imaginary-type activation functions. Based on a fixed theorem and stability definition, sufficient criteria are established for the existence and stability of multiple equilibria of complex-valued recurrent neural networks. The number of stable equilibria is larger than that of real-valued recurrent neural networks, which can be used to achieve high-capacity associative memories. One numerical example is provided to show the effectiveness and superiority of the presented results. 展开更多
关键词 complex-valued recurrent neural network discontinuous real-imaginary-type activation function MULTISTABILITY delay
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Research on the Effect of Artificial Intelligence Real Estate Forecasting Using Multiple Regression Analysis and Artificial Neural Network: A Case Study of Ghana 被引量:2
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作者 Madami Michael Ishaku Hill Isaac Lewu 《Journal of Computer and Communications》 2021年第10期1-14,共14页
To transition from conventional to intelligent real estate, the real estate industry must enhance its embrace of disruptive technology. Even though the real estate auction market has grown in importance in the financi... To transition from conventional to intelligent real estate, the real estate industry must enhance its embrace of disruptive technology. Even though the real estate auction market has grown in importance in the financial, economic, and investment sectors, few artificial intelligence-based research has tried to predict the auction values of real estate in the past. According to the objectives of this research, artificial intelligence and statistical methods will be used to create forecasting models for real estate auction prices. A multiple regression model and an artificial neural network are used in conjunction with one another to build the forecasting models. For the empirical study, the study utilizes data from Ghana apartment auctions from 2016 to 2020 to anticipate auction prices and evaluate the forecasting accuracy of the various models available at the time. Compared to the conventional Multiple Regression Analysis, using artificial intelligence systems for real estate appraisal is becoming a more viable option (MRA). The Artificial Neural network model exhibits the most outstanding performance, and efficient zonal segmentation based on the auction evaluation price enhances the model’s prediction accuracy even more. There is a statistically significant difference between the two models when it comes to forecasting the values of real estate auctions. 展开更多
关键词 real Estate Forecasting Artificial Intelligence Artificial Neural networks Multiple Regression Analysis
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基于深度学习的轻量级实时图像分割方法研究 被引量:2
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作者 李建锋 熊明强 +3 位作者 陈园琼 王宗达 向涛 孙培玮 《通信学报》 北大核心 2025年第2期176-190,共15页
针对深度学习在各领域应用中因模型复杂度提升而引发的计算与存储负担,尤其在图像分割任务中面临的算法复杂性、实时响应不足及高内存占用问题,提出了一种轻量级且高效的分割网络架构——多尺度叠加融合网络(MSFNet)。MSFNet设计了一个... 针对深度学习在各领域应用中因模型复杂度提升而引发的计算与存储负担,尤其在图像分割任务中面临的算法复杂性、实时响应不足及高内存占用问题,提出了一种轻量级且高效的分割网络架构——多尺度叠加融合网络(MSFNet)。MSFNet设计了一个双分支多尺度边界融合模块,该模块通过融合不同尺度的特征信息与边界细节,有效提升了图像分割精度,同时显著减少了模型参数量。实验结果表明,MSFNet在3个公开数据集上表现优异,其模型参数量仅为0.6×10^(6),在RTX 3070 GPU上处理大小为800像素×800像素的图像仅需12 ms,显著提升了分割任务的执行效率和资源利用率。因此,该模型特别适合应用于资源有限的边缘设备或移动设备中,为实时图像分割应用提供了有力的技术支撑。 展开更多
关键词 图像分割 轻量级实时网络 双分支多尺度边界融合模块
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A Survey on Real-Time MAC Protocols in Wireless Sensor Networks
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作者 Zheng Teng Ki-Il Kim 《Communications and Network》 2010年第2期104-112,共9页
As wireless sensor network becomes pervasive, new requirements have been continuously emerged. How-ever, the most of research efforts in wireless sensor network are focused on energy problem since the nodes are usuall... As wireless sensor network becomes pervasive, new requirements have been continuously emerged. How-ever, the most of research efforts in wireless sensor network are focused on energy problem since the nodes are usually battery-powered. Among these requirements, real-time communication is one of the big research challenges in wireless sensor networks because most of query messages carry time information. To meet this requirement, recently several real-time medium access control protocols have been proposed for wireless sensor networks in the literature because waiting time to share medium on each node is one of main source for end-to-end delay. In this paper, we first introduce the specific requirement of wireless sensor real-time MAC protocol. Then, a collection of recent wireless sensor real-time MAC protocols are surveyed, classified, and described emphasizing their advantages and disadvantages whenever possible. Finally we present a dis-cussion about the challenges of current wireless sensor real-time MAC protocols in the literature, and show the conclusion in the end. 展开更多
关键词 WIRELESS Sensor networks MEDIUM ACCESS Control (MAC) real-TIME
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基于Real ESRGAN的视频修复系统研究
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作者 黄杰 夏远洋 +3 位作者 杨晓杰 王思洁 田佩 刘涛 《科技创新与应用》 2024年第15期46-49,54,共5页
图像修复和视频修复是计算机视觉的一项重要任务,其中图像修复又是视频修复的基础。为此,如何有效提升图像质量是实现视频质量提升的关键。传统的图像修复算法主要以样本信息为基础,通过对样本内容的扩撒来实现对破损区域的修复;由于这... 图像修复和视频修复是计算机视觉的一项重要任务,其中图像修复又是视频修复的基础。为此,如何有效提升图像质量是实现视频质量提升的关键。传统的图像修复算法主要以样本信息为基础,通过对样本内容的扩撒来实现对破损区域的修复;由于这种方式对于图像样本有一定要求,从而制约传统图像修复技术的发展。为此,以生成新图像内容为基础的神经网络如GAN的出现,为图像修复技术转向深度学习提供方向。该课题主要以Real ESRGAN网络的图像修复技术为基础,通过对音频视频数据的隔离处理以及相同帧数据的优化和标记,构建视频修复处理流程。通过对随机视频样本的测试,并通过对单帧图片质量和视频数据流畅性与协调性的评估,该视频处理方法表现出较好的系统性能。 展开更多
关键词 图像分割 神经网络 视频修复 real ESRGAN 图像修复
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光纤传感网络混合式入侵行为实时检测研究 被引量:1
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作者 陆思辰 王福军 《激光杂志》 北大核心 2025年第1期202-207,共6页
混合式入侵行为往往在一个或多个局部位置出现,且在时间上存在一定的聚集性,无法很好地捕捉其复杂特征,为此提出光纤传感网络混合式入侵行为实时检测方法。以平均过零率和短时能量作为指标对某段信号进行分割处理,减少不断累加的处理延... 混合式入侵行为往往在一个或多个局部位置出现,且在时间上存在一定的聚集性,无法很好地捕捉其复杂特征,为此提出光纤传感网络混合式入侵行为实时检测方法。以平均过零率和短时能量作为指标对某段信号进行分割处理,减少不断累加的处理延时,提取可能存在入侵行为的光纤传感信号。通过高阶谱分析、样本熵分析和奇异值分析进一步提取信号特征,构建并利用多层梯度下降法训练多个深度神经网络,将所提取的特征输入至对应深度神经网络中,经由Softmax函数输出混合式入侵行为检测结果,最后采用改进的DS证据理论关联融合各深度神经网络输出的检测结果,实现光纤传感网络混合式入侵行为实时检测。实验结果表明,所提方法入侵行为检测结果更准确、内存占用率和CPU使用率较低。 展开更多
关键词 光纤传感网络 混合式入侵行为 实时检测 深度神经网络 奇异值分解
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A Novel Real-Time Fault Diagnostic System for Steam Turbine Generator Set by Using Strata Hierarchical Artificial Neural Network
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作者 Changfeng YAN Hao ZHANG Lixiao WU 《Energy and Power Engineering》 2009年第1期7-16,共10页
The real-time fault diagnosis system is very great important for steam turbine generator set due to a serious fault results in a reduced amount of electricity supply in power plant. A novel real-time fault diagnosis s... The real-time fault diagnosis system is very great important for steam turbine generator set due to a serious fault results in a reduced amount of electricity supply in power plant. A novel real-time fault diagnosis system is proposed by using strata hierarchical fuzzy CMAC neural network. A framework of the fault diagnosis system is described. Hierarchical fault diagnostic structure is discussed in detail. The model of a novel fault diagnosis system by using fuzzy CMAC are built and analyzed. A case of the diagnosis is simulated. The results show that the real-time fault diagnostic system is of high accuracy, quick convergence, and high noise rejection. It is also found that this model is feasible in real-time fault diagnosis. 展开更多
关键词 real-TIME FAULT diagnosis STRATA HIERARCHICAL artificial neural network fuzzy CMAC
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数实产业技术融合对我国企业全球价值链稳定性的影响研究 被引量:7
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作者 张兵 张露文 周宏伟 《国际经贸探索》 北大核心 2025年第2期36-53,共18页
文章基于专利引用网络构建企业层面数实产业技术融合指标,从理论和实证两个方面深入探讨了数实产业技术融合对我国企业全球价值链稳定性的影响及其作用机制。研究结果表明,企业进行数实产业技术融合能显著提升其全球价值链的稳定性。融... 文章基于专利引用网络构建企业层面数实产业技术融合指标,从理论和实证两个方面深入探讨了数实产业技术融合对我国企业全球价值链稳定性的影响及其作用机制。研究结果表明,企业进行数实产业技术融合能显著提升其全球价值链的稳定性。融合垂直深度越深、水平广度越广,这一“稳链”作用越明显。机制分析表明,企业通过数实产业技术融合能够扩大出口产品范围、优化进口中间品布局策略及拓展专利知识宽度,从而提升我国企业全球价值链的稳定性。在异质性分析层面,数实产业技术融合对企业全球价值链稳定性的影响在具有不同内部特征和外部环境的企业中存在明显差异。文章为新时代促进数字新质生产力与实体产业的深度融合、提升企业全球价值链稳定性提供了实证支持与政策指引。 展开更多
关键词 数实产业技术融合 专利引用网络 全球价值链稳定性 贸易策略优化
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数实融合、资源配置与绿色转型绩效 被引量:1
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作者 王浩 蒋金荷 《北京工业大学学报(社会科学版)》 北大核心 2025年第5期89-107,共19页
数字经济和实体经济深度融合引发了从生产要素到生产力再到生产关系的系统性变革,是推动经济社会发展全面绿色转型的重要一环。基于2011—2021年全国244个地级市面板数据,在构建数字经济与实体经济融合水平及城市绿色转型绩效测度指标... 数字经济和实体经济深度融合引发了从生产要素到生产力再到生产关系的系统性变革,是推动经济社会发展全面绿色转型的重要一环。基于2011—2021年全国244个地级市面板数据,在构建数字经济与实体经济融合水平及城市绿色转型绩效测度指标的基础上,同时从理论和实证层面研究了数实融合对城市绿色转型绩效的影响和作用机理。研究发现:数实融合对城市绿色转型绩效有显著的促进作用,其重要途径是提高资源配置效率,同时市场一体化水平和数字治理存在正向调节作用。而异质性分析表明,数字鸿沟的存在影响城市绿色转型绩效,技术水平高的城市能够享受更明显的数字红利,相比于中部地区,东部地区和西部地区数实融合能够带来更为显著的促进作用。相较于资源型城市,非资源型城市数实融合对城市绿色转型绩效的促进作用更为明显。由此,从拓宽数字经济与实体经济融合深度广度、完善数字平台和数据市场建设及促进协同发展等方面对提高绿色转型绩效提出政策建议。 展开更多
关键词 数实融合 绿色转型绩效 网络SBM 资源配置
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基于动态贝叶斯网络的地下道路行车风险评估 被引量:1
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作者 尚婷 郭明洋 +1 位作者 唐伯明 徐钰婷 《交通运输系统工程与信息》 北大核心 2025年第3期232-245,共14页
为探究地下道路不同交通标志信息密度下驾驶员行车风险动态演变规律,本文以驾驶员视觉负荷为表征指标,利用自然驾驶试验采集驾驶员眼动数据,基于动态贝叶斯网络理论构建驾驶员行车风险评价模型。基于香农信息熵量化交通标志信息量,构建... 为探究地下道路不同交通标志信息密度下驾驶员行车风险动态演变规律,本文以驾驶员视觉负荷为表征指标,利用自然驾驶试验采集驾驶员眼动数据,基于动态贝叶斯网络理论构建驾驶员行车风险评价模型。基于香农信息熵量化交通标志信息量,构建考虑交通标志信息量呈现速率的交通标志信息密度模型。选取解放碑地下道路4种不同交通标志信息密度的路段开展实车试验,提取并分析不同路段的驾驶员视觉特性指标。引入动态贝叶斯网络理论动态概率预测及推理评估驾驶员行车风险,由诊断推理、敏感性分析和影响链分析得到影响驾驶员行车风险的关键风险因素。结果表明:驾驶员注视持续时间、水平/垂直扫视幅度、水平/垂直扫视速度及瞳孔面积变化速率与交通标志信息密度呈正相关,眨眼频率与交通标志信息密度呈负相关;驾驶员行车风险发生概率随时间呈动态变化,先上升,后趋于平缓,且随交通标志信息密度的增加,4个路段的风险概率分别稳定于22.6%,35.7%,40.1%和43.8%;驾驶员行车风险受注视状态等环节风险因素影响较大,包括注视持续时间、瞳孔面积变化速率和眨眼频率等关键风险因素。 展开更多
关键词 交通工程 视觉负荷 动态贝叶斯网络 地下道路 实车试验 风险评估
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基于时空特性的VLC/RF网络决策机制 被引量:1
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作者 陈北辰 陈硕 +1 位作者 孙洪亮 李丹 《科学技术与工程》 北大核心 2025年第3期1110-1116,共7页
针对室内可见光通信(visible light communication,VLC)与射频(radio frequency,RF)通信异构网络中易因瞬态链路变化而导致频繁切换的问题,提出了一种基于时空特性的VLC/RF网络决策机制。首先,在离线采样阶段,通过对室内网格点的空间位... 针对室内可见光通信(visible light communication,VLC)与射频(radio frequency,RF)通信异构网络中易因瞬态链路变化而导致频繁切换的问题,提出了一种基于时空特性的VLC/RF网络决策机制。首先,在离线采样阶段,通过对室内网格点的空间位置、带宽、接收信号强度、时延与信噪比等特征数据,在控制器中对特征数据进行处理并转换成比例权重,构建数据库。然后,在实时决策阶段,终端将采集到的特征数据反馈给控制器,通过跟控制器数据库中的信息比对来确定用户终端位置,提取出数据库中当前位置的优先链路并连接。最后,利用链路决策模型实时推导出网络通信指数,通过决策函数对数据库中的链路比例权重与网络通信指数聚合计算,求解出最优链路,并使用驻留定时器提高通信质量。仿真结果表明,本文切换算法与传统的模糊逻辑切换算法和等效信噪比(signal-to-noise ratio,SNR)垂直切换决策算法相比,有效降低了平均切换次数、切换中断概率。本文算法可以实现室内异构网络的智能化管理,改善用户体验质量。 展开更多
关键词 可见光通信 异构网络 模糊系统 实时决策
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