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Physical Network Approach Applied to Wind Turbine Modeling with Simscape Language 被引量:1
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作者 Elhaini Jamila Saka Abdelmjid 《Open Journal of Modelling and Simulation》 2014年第2期77-89,共13页
Model-Based Design is an efficient and cost-effective way to develop controls, signal processing, image processing, communications, mechatronics, and other embedded systems. Rather than re-lying on physical prototypes... Model-Based Design is an efficient and cost-effective way to develop controls, signal processing, image processing, communications, mechatronics, and other embedded systems. Rather than re-lying on physical prototypes and textual specifications, Model-Based Design uses a system model as an executable specification throughout development. It supports system- and component-level design and simulation, automatic code generation, and continuous test and verification. This paper is focused firstly on the so-called model-based design and aims at presenting an up-to-date state of the art in this important field. Secondly, it develops a model based design for wind energy systems. Mathematical formulations and numerical implementations for different components of wind energy systems are highlighted with Simscape language. Finally, results are derived from simulations. 展开更多
关键词 MATHEMATICAL Modeling MODEL-BASED Design Simscape PHYSICAL network approach WIND Energy Systems
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A Neural Network Approach for Designing 2-D FIR Filters with Arbitrary Magnitude Responses
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作者 Xiaohua Wang Yigang He 《通讯和计算机(中英文版)》 2006年第3期66-71,共6页
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A neural network approach based on more input neurons to predict nuclear mass 被引量:1
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作者 Tian-Liang Zhao Hong-Fei Zhang 《Chinese Physics C》 SCIE CAS CSCD 2022年第4期123-130,共8页
The study of nuclear mass is very important,and the neural network(NN)approach can be used to improve the prediction of nuclear mass for various models.Considering the number of valence nucleons of protons and neutron... The study of nuclear mass is very important,and the neural network(NN)approach can be used to improve the prediction of nuclear mass for various models.Considering the number of valence nucleons of protons and neutrons separately in the input quantity of the NN model,the root-mean-square deviation of binding energy between data from AME2016 and liquid drop model calculations for 2314 nuclei was reduced from 2.385 MeV to 0.203 MeV.In addition,some defects in the Weizsacker-Skyrme(WS)-type model were repaired,which well reproduced the two-neutron separation energy of the nucleus synthesized recently by RIKEN RI Beam Factory[Phys.Rev.Lett.125,(2020)122501].The masses of some of the new nuclei appearing in the latest atomic mass evaluation(AME2020)are also well reproduced.However,the results of neural network methods for predicting the description of regions far from known atomic nuclei need to be further improved.This study shows that such a statistical model can be a tool for systematic searching of nuclei beyond existing experimental data. 展开更多
关键词 neural network approach liquid-drop model binding energy
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Magnetic moment predictions of odd-A nuclei with the Bayesian neural network approach 被引量:1
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作者 Zilong Yuan Dachuan Tian +1 位作者 Jian Li Zhongming Niu 《Chinese Physics C》 SCIE CAS CSCD 2021年第12期147-154,共8页
The Bayesian neural network approach has been employed to improve the nuclear magnetic moment predictions of odd-A nuclei.The Schmidt magnetic moment obtained from the extreme single-particle shell model makes large r... The Bayesian neural network approach has been employed to improve the nuclear magnetic moment predictions of odd-A nuclei.The Schmidt magnetic moment obtained from the extreme single-particle shell model makes large root-mean-square(rms)deviations from data,i.e.,0.949μN and 1.272μN for odd-neutron nuclei and odd-proton nuclei,respectively.By including the dependence of the nuclear spin and Schmidt magnetic moment,the machine-learning approach precisely describes the magnetic moments of odd-A uclei with rms deviations of 0.036μN for odd-neutron nuclei and 0.061μN for odd-proton nuclei.Furthermore,the evolution of magnetic moments along isotopic chains,including the staggering and sudden jump trend,which are difficult to describe using nuclear models,have been well reproduced by the Bayesian neural network(BNN)approach.The magnetic moments of doubly closed-shell±1 nuclei,for example,isoscalar and isovector magnetic moments,have been well studied and compared with the corresponding non-relativistic and relativistic calculations. 展开更多
关键词 magnetic moment odd-A nuclei Bayesian neural network approach
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Universal Electrochemical/Chemical Simulator Based on an Exponentially Expanding Grid Network Approach
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作者 邓兆祥 林祥钦 童中华 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第7期719-726,共8页
A universal simulator capable of simulating virtually any user-defined electrochemical/chemical problems in one-dimensional diffusion geometry was developed based on an exponentially expanding grid modification of the... A universal simulator capable of simulating virtually any user-defined electrochemical/chemical problems in one-dimensional diffusion geometry was developed based on an exponentially expanding grid modification of the existing network approach. Some generalized reaction-diffusion governing equations of an arbitrary electrochemical/chemical process were derived, and program controlled automatic generation of the corresponding PSPICE netlist file was realized. On the basis of the above techniques, a universal simulator package was realized, which is capable of dealing with arbitrarily complex electrochemical/chemical problems with one-dimensional diffusion geometry such as planar diffusion, spherical diffusion, cylindrical diffusion and rotational disk diffusion-convection processes. The building of such a simulator is easy and thus it would be very convenient to have it updated for simulations of newly raised electrochemical problems. 展开更多
关键词 electrochemical simulator electrode process network approach exponentially expanding grid
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Research on a Neural Network Approach Based Diagnosis Expert System of Crack Control in Massive Concrete
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作者 HAN Liu-xin 1, WANG Huan-chen 1,\ ZHANG Xian-hui 2 1.Institute of Systems Engineering, Shanghai Jiaotong University, Shanghai 200052, China 2.Shanghai Yongye Enterprise (Group) Co., Ltd,200021 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2001年第3期359-365,共7页
A detailed study of the capabilities of artificial neural networks to diagnoses cracks in massive concrete structures is presented. This paper includes the components of the expert system such as design thought, basic... A detailed study of the capabilities of artificial neural networks to diagnoses cracks in massive concrete structures is presented. This paper includes the components of the expert system such as design thought, basic structure, building of knowledge base and the implementation of neural network applied model. The realizing method of neural network based clustering algorithm in the knowledge base and self study is analyzed emphatically and stimulated by means of the computer. From the above study, some important conclusions have been drawn and some new viewpoints have been suggested. 展开更多
关键词 neural network approach expert system crack control
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Exponentially Expanded Grid Network Approach (EEGNA): An Efficient Way for the Simulation of Stiff Electrochemical Problems
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作者 邓兆祥 林祥钦 童中华 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2003年第9期1137-1145,共9页
The exponentially expanded space grid was incorporated into the network approach to overcome the problem of low simulation efficiency during the simulations of electrochemical problems with stiff kinetics or wide disp... The exponentially expanded space grid was incorporated into the network approach to overcome the problem of low simulation efficiency during the simulations of electrochemical problems with stiff kinetics or wide dispersion of diffusion coefficients, resulting in an effective electrochemical simulation method: exponentially expanded grid network approach (EEGNA). The stability and accuracy of the EEGNA for the simulation of various electrode processes coupled with different types of homogeneous reactions were investigated. 展开更多
关键词 electrochemical simulation exponentially expanded grid network approach stiff problem
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Artificial Neural Network(ANN)Approach for Predicting Concrete Compressive Strength by SonReb
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作者 Mario Bonagura Lucio Nobile 《Structural Durability & Health Monitoring》 EI 2021年第2期125-137,共13页
The compressive strength of concrete is one of most important mechanical parameters in the performance assessment of existing reinforced concrete structures.According to various international codes,core samples are dr... The compressive strength of concrete is one of most important mechanical parameters in the performance assessment of existing reinforced concrete structures.According to various international codes,core samples are drilled and tested to obtain the concrete compressive strengths.Non-destructive testing is an important alternative when destructive testing is not feasible without damaging the structure.The commonly used non-destructive testing(NDT)methods to estimate the in-situ values include the Rebound hammer test and the Ultrasonic Pulse Velocity test.The poor reliability of these tests due to different aspects could be partially contrasted by using both methods together,as proposed.in the SonReb method.There are three techniques that are commonly used to predict the compressive strength of concrete based on the SonReb measurements:computational modeling,artificial intelligence,and parametric multi-variable regression models.In a previous study the accuracy of the correlation formulas deduced from the last technique has been investigated in comparison with the effective compressive strengths based on destructive test results on core drilled in adjacent locations.The aim of this study is to verify the accuracy of Artificial Neural Approach comparing the estimated compressive strengths based on NDT measured parameters with the same effective compressive strengths.The comparisons show the best performance of ANN approach. 展开更多
关键词 Compressive concrete strength destructive tests non-destructive test ultrasonic pulse velocity rebound index SonReb method artificial neural network approach
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An linear matrix inequality approach to global synchronisation of non-parameter perturbations of multi-delay Hopfield neural network
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作者 邵海见 蔡国梁 汪浩祥 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期212-217,共6页
In this study, a successful linear matrix inequality approach is used to analyse a non-parameter perturbation of multi-delay Hopfield neural network by constructing an appropriate Lyapunov-Krasovskii functional. This ... In this study, a successful linear matrix inequality approach is used to analyse a non-parameter perturbation of multi-delay Hopfield neural network by constructing an appropriate Lyapunov-Krasovskii functional. This paper presents the comprehensive discussion of the approach and also extensive applications. 展开更多
关键词 Hopfield neural network LMI approach global synchronisation sliding mode control
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Neural Network Based Normalized Fusion Approaches for Optimized Multimodal Biometric Authentication Algorithm 被引量:2
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作者 E. Sujatha A. Chilambuchelvan 《Circuits and Systems》 2016年第8期1199-1206,共8页
A multimodal biometric system is applied to recognize individuals for authentication using neural networks. In this paper multimodal biometric algorithm is designed by integrating iris, finger vein, palm print and fac... A multimodal biometric system is applied to recognize individuals for authentication using neural networks. In this paper multimodal biometric algorithm is designed by integrating iris, finger vein, palm print and face biometric traits. Normalized score level fusion approach is applied and optimized, encoded for matching decision. It is a multilevel wavelet, phase based fusion algorithm. This robust multimodal biometric algorithm increases the security level, accuracy, reduces memory size and equal error rate and eliminates unimodal biometric algorithm vulnerabilities. 展开更多
关键词 Multimodal Biometrics Score Level Fusion approach Neural network OPTIMIZATION
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Prediction of nuclear charge density distribution with feedback neural network 被引量:5
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作者 Tian‑Shuai Shang Jian Li Zhong‑Ming Niu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第12期24-35,共12页
Nuclear charge density distribution plays an important role in both nuclear and atomic physics,for which the two-parameter Fermi(2pF)model has been widely applied as one of the most frequently used models.Currently,th... Nuclear charge density distribution plays an important role in both nuclear and atomic physics,for which the two-parameter Fermi(2pF)model has been widely applied as one of the most frequently used models.Currently,the feedforward neural network has been employed to study the available 2pF model parameters for 86 nuclei,and the accuracy and precision of the parameter-learning effect are improved by introducing A^(1∕3)into the input parameter of the neural network.Furthermore,the average result of multiple predictions is more reliable than the best result of a single prediction and there is no significant difference between the average result of the density and parameter values for the average charge density distribution.In addition,the 2pF parameters of 284(near)stable nuclei are predicted in this study,which provides a reference for the experiment. 展开更多
关键词 Charge density distribution Two-parameter Fermi model Feedforward neural network approach
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Evolution, resilience and causes of global petroleum gas trade networks: 1995-2020 被引量:2
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作者 Na Li Yi-Ran Song +1 位作者 Ying Wang Chun-Bao Ge 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3656-3674,共19页
Based on the HS 4-digit code trade data in UNCOMTRADE from 1995 to 2020, this paper analyzes the characteristics of the evolution of the global PG trade network using the complex network approach and analyzes the chan... Based on the HS 4-digit code trade data in UNCOMTRADE from 1995 to 2020, this paper analyzes the characteristics of the evolution of the global PG trade network using the complex network approach and analyzes the changes in its resilience at the overall and country levels, respectively. The results illustrated that:(1) The scale of the global PG trade network tends to expand, and the connection is gradually tightened, experiencing a change from a “supply-oriented” to a “supply-and-demand” pattern, in which the U.S., Russia, Qatar, and Australia have gradually replaced Canada, Japan, and Russia to become the core trade status, while OPEC countries such as Qatar, Algeria, and Kuwait mainly rely on PG exports to occupy the core of the global supply, and the trade status of other countries has been dynamically alternating and evolving.(2) The resilience of the global PG trade network is lower than that of the random network and decreases non-linearly with more disrupted countries. Moreover, the impact of the U.S. is more significant than the rest of countries. Simulations using the exponential random graph model(ERGM) model revealed that national GDP, institutional quality, common border and RTA network are the determinants of PG trade network formation, and the positive impact of the four factors not only varies significantly across regions and stages, but also increases with national network status. 展开更多
关键词 Petroleum gas Complex network approach network resilience Exponential random graph model
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Active Network研究综述 被引量:1
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作者 夏正友 钟亦平 张世永 《小型微型计算机系统》 CSCD 北大核心 2003年第10期1821-1824,共4页
介绍了两种实现 Active Network方法 ,描述 Active Network结构与组成、Active Network封装协议和 ActiveNetwork编程模型 .讨论国内外对 Active Network的研究成果和进展 .在该文最后对 Active network研究作了总结 。
关键词 Active-network 离散方法 集成方法 综述 封装协议 编程模型
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基于数据-模型混合驱动方法的多类型移动应急资源优化调度策略
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作者 江昌旭 周龙灿 +3 位作者 庄鹏威 许浩 林俊杰 邵振国 《电网技术》 北大核心 2026年第2期858-868,I0136-I0146,共22页
为有效提升配电网韧性,提出了一种基于数据-模型混合驱动的多类型移动应急资源优化调度方法。首先,考虑到交通道路状态动态变化对移动储能车(mobile energy storage system,MESS)和应急抢修队(repair crew,RC)策略的影响,构建了以电力-... 为有效提升配电网韧性,提出了一种基于数据-模型混合驱动的多类型移动应急资源优化调度方法。首先,考虑到交通道路状态动态变化对移动储能车(mobile energy storage system,MESS)和应急抢修队(repair crew,RC)策略的影响,构建了以电力-交通耦合网总损失成本最小为目标的多类型移动应急资源随机优化调度模型。然后,为了实时准确地求解MESS和RC最优路由和调度策略,提出了一种数据-模型混合驱动方法对所构建的复杂非线性随机优化模型进行求解。在数据驱动部分提出一种图注意力网络多智能体强化学习算法,以求解考虑交通网道路修复时间和移动应急资源邻接关系动态变化等不确定因素的MESS和RC最优路由策略。所提算法有效结合多种改进策略和优先经验回放策略以提高算法的采样效率和训练效果。在模型驱动部分采用二阶锥松弛和大M法将多类型移动应急资源优化调度问题构建为混合整数二阶锥规划模型以求解可再生能源出力和配电网负荷变化影响下MESS和RC最优调度策略。最后,在2个不同规模的电力-交通耦合网中验证所提方法的有效性、泛化能力和可拓展能力。 展开更多
关键词 移动应急资源 配电网韧性 路由和调度策略 数据-模型混合驱动方法 图注意力网络多智能体强化学习
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平原河网地区农业面源污染生态治理模式构建及案例分析
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作者 赵蕊 陈小华 刘熠阳 《华东师范大学学报(自然科学版)》 北大核心 2026年第1期120-131,共12页
平原河网地区农业面源污染来源广泛、构成复杂.尽管各地已针对该类污染开展多项治理实践,但如何依据区域特点精准选择适配的治理模式,仍是当前亟待解决的问题.以长三角地区为研究区域,通过实地调研系统梳理该区域农业面源污染治理经验,... 平原河网地区农业面源污染来源广泛、构成复杂.尽管各地已针对该类污染开展多项治理实践,但如何依据区域特点精准选择适配的治理模式,仍是当前亟待解决的问题.以长三角地区为研究区域,通过实地调研系统梳理该区域农业面源污染治理经验,提炼形成农田内部生态改造、塘田一体化、农(林)湿复合3种核心治理模式.为深入验证治理成效,研究进一步聚焦塘田一体化及农(林)湿复合模式,选取上海市青浦区、嘉定区、松江区的农业面源生态治理作为典型案例,通过监测农田退水集中治理前后的水质变化,定量分析主要污染物指标的削减率.为长三角地区农业面源污染的系统化、精准化治理提供数据支撑与实践参考,也为同类平原河网地区的污染治理模式选择提供借鉴. 展开更多
关键词 面源污染 平原河网地区 生态治理模式 氮磷
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高超声速进气道内收缩基准流场的残差网络智能预测方法
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作者 杨孔强 熊冰 +2 位作者 范晓樯 王翼 唐啸 《国防科技大学学报》 北大核心 2026年第1期28-39,共12页
为了提高内转式进气道的设计效率,实现对内收缩基准流场的快速预测,采用准均匀B样条方法实现内收缩基准流场的参数化设计,提出了基于深度学习残差神经网络架构的流场预测模型。结合峰值信噪比、结构相似性指数等图像质量评估方法,对预... 为了提高内转式进气道的设计效率,实现对内收缩基准流场的快速预测,采用准均匀B样条方法实现内收缩基准流场的参数化设计,提出了基于深度学习残差神经网络架构的流场预测模型。结合峰值信噪比、结构相似性指数等图像质量评估方法,对预测流场进行定量评价,并从中提取壁面特性分布、激波形态等关键流场特性,以实现基于基准流场几何参数快速获取流场云图和特性参数分布的目标。研究结果表明,所构建的流场快速预测模型精度较高,其整体平均峰值信噪比为42.51 dB,平均结构相似性指数为0.9973,且能有效地从预测结果中提取流场的关键特性与参数分布,为内收缩基准流场的快速设计与优化提供有力支持。 展开更多
关键词 高超声速 内收缩 基准流场 参数方法 流场预测 残差神经网络
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Smart Service System(SSS):A Novel Architecture Enabling Coordination of Heterogeneous Networking Technologies and Devices for Internet of Things 被引量:6
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作者 yongan guo hongbo zhu longxiang yang 《China Communications》 SCIE CSCD 2017年第3期130-144,共15页
In Internet of Things(IoT), the devices or terminals are connected with each other, which can be very diverse over the wireless networks. Unfortunately, the current devices are not designed to communicate with the col... In Internet of Things(IoT), the devices or terminals are connected with each other, which can be very diverse over the wireless networks. Unfortunately, the current devices are not designed to communicate with the collocated devices which employ different communication technologies. Consequently, the communication between these devices will be realized only by using the gateway nodes. This will cause the inefficient use of wireless resources. Therefore, in this paper, a smart service system(SSS) architecture is proposed, which consists of smart service terminal(SST), and smart service network(SSN), to realize the Io T in a general environment with diverse communication networks, devices, and services. The proposed architecture has the following advantages: i) the devices in this architecture cover multiple types of terminals and sensor-actuator devices; ii) the communications network therein is a converged network, and will coordinate multiple kinds of existing and emerging networks. This converged network offers ubiquitous access for various sensors and terminals; iii) the architecture has services and applications covering all smart service areas. It also provides theadaptability to new services and applications. A SSS architecture-based smart campus system was developed and deployed. Evaluation experiments of the proposed smart campus system demonstrate the SSS's advantages over the existing counterparts, and verify the effectiveness of the proposed architecture. 展开更多
关键词 Internet of Things network architecture clean slate evolutionary approach network heterogeneity reconfiguration
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Synthesis of the fluid machinery network in a circulating water system 被引量:2
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作者 Wei Gao Xiao Feng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第3期587-597,共11页
Energy consumption of the fluid machinery network in a circulating water system takes up a large part of energy consumption in the process industry, so optimization on the network will enhance the economic and environ... Energy consumption of the fluid machinery network in a circulating water system takes up a large part of energy consumption in the process industry, so optimization on the network will enhance the economic and environmental performance of the industry. In this paper, a synthesis approach is proposed to obtain the optimal network structure. The effective height curves are used as tools to perform energy analysis, so that the potential placement of water turbines and auxiliary pumps can be determined with energy benefit. Then economic optimization is carried out, by the mathematical model with the total cost as the objective function, to identify the branches for water turbines and auxiliary pumps with economic benefit. In this way, the optimal fluid machinery network structure can be obtained. The results of case study indicate that the proposed synthesis approach to optimize the fluid machinery network will obtain more remarkable benefits on economy, compared to optimizing only the water turbine network or pump network. The results under different flowrates of circulating water reveal that using a water turbine to recover power or adding an auxiliary pump to save energy in branches are only suitable to the flowrate in a certain range. 展开更多
关键词 FLUID MACHINERY network SYNTHESIS approach Flowrate RANGE network STRUCTURE
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面向智慧农业的LoRa-WSN自适应拓扑重构方法
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作者 崔运辉 《智能物联技术》 2026年第1期140-144,共5页
针对智慧农业远距离无线电-无线传感器网络(Long Range Radio-Wireless Sensor Network,LoRaWSN)传统拓扑难以适配动态场景的问题,先分析星型、树型分层、传统Mesh这3类主流拓扑的核心劣势(如星型链路适配缺失、树型容错性差、传统Mesh... 针对智慧农业远距离无线电-无线传感器网络(Long Range Radio-Wireless Sensor Network,LoRaWSN)传统拓扑难以适配动态场景的问题,先分析星型、树型分层、传统Mesh这3类主流拓扑的核心劣势(如星型链路适配缺失、树型容错性差、传统Mesh的路由与能耗缺陷),再提出基于链路质量的多跳自适应传输系统,包括链路质量指示-地形适应因子(Link Quality Indicator-terrain adaptation factor,LQI-τ)协同建模、改进粒子群优化(Particle Swarm Optimization,PSO)能耗优化、主成分分析(Principal Component Analysis,PCA)+卡尔曼滤波质量模型与数据优先级差异化保障策略。实验结果表明,所提方法可有效提升数据传输成功率与网络生存周期,降低传输延迟与节点能耗,精准满足智慧农业动态场景需求。 展开更多
关键词 智慧农业 远距离无线电-无线传感器网络(LoRa-WSN) 自适应拓扑 重构方法
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A COMPOUND POISSON MODEL FOR LEARNING DISCRETE BAYESIAN NETWORKS 被引量:2
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作者 Abdelaziz GHRIBI Afif MASMOUDI 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1767-1784,共18页
We introduce here the concept of Bayesian networks, in compound Poisson model, which provides a graphical modeling framework that encodes the joint probability distribution for a set of random variables within a direc... We introduce here the concept of Bayesian networks, in compound Poisson model, which provides a graphical modeling framework that encodes the joint probability distribution for a set of random variables within a directed acyclic graph. We suggest an approach proposal which offers a new mixed implicit estimator. We show that the implicit approach applied in compound Poisson model is very attractive for its ability to understand data and does not require any prior information. A comparative study between learned estimates given by implicit and by standard Bayesian approaches is established. Under some conditions and based on minimal squared error calculations, we show that the mixed implicit estimator is better than the standard Bayesian and the maximum likelihood estimators. We illustrate our approach by considering a simulation study in the context of mobile communication networks. 展开更多
关键词 Bayesian network compound Poisson distribution multinomial distribution implicit approach mobile communication networks
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