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Link-16 anti-jamming performance evaluation based on grey relational analysis and cloud model
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作者 NING Xiaoyan WANG Ying +1 位作者 WANG Zhenduo SUN Zhiguo 《Journal of Systems Engineering and Electronics》 2025年第1期62-72,共11页
Anti-jamming performance evaluation has recently received significant attention. For Link-16, the anti-jamming performance evaluation and selection of the optimal anti-jamming technologies are urgent problems to be so... Anti-jamming performance evaluation has recently received significant attention. For Link-16, the anti-jamming performance evaluation and selection of the optimal anti-jamming technologies are urgent problems to be solved. A comprehensive evaluation method is proposed, which combines grey relational analysis (GRA) and cloud model, to evaluate the anti-jamming performances of Link-16. Firstly, on the basis of establishing the anti-jamming performance evaluation indicator system of Link-16, the linear combination of analytic hierarchy process(AHP) and entropy weight method (EWM) are used to calculate the combined weight. Secondly, the qualitative and quantitative concept transformation model, i.e., the cloud model, is introduced to evaluate the anti-jamming abilities of Link-16 under each jamming scheme. In addition, GRA calculates the correlation degree between evaluation indicators and the anti-jamming performance of Link-16, and assesses the best anti-jamming technology. Finally, simulation results prove that the proposed evaluation model can achieve the objective of feasible and practical evaluation, which opens up a novel way for the research of anti-jamming performance evaluations of Link-16. 展开更多
关键词 LINK-16 ANTI-JAMMING grey relational analysis(GRA) cloud model combination weights
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Control model for burning-bubble clouds formed by confined meltcast explosives under thermal stimulation
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作者 Zhi Li Zhuoping Duan +4 位作者 Zhiling Bai Jixuan Jiao Liji Xu Liansheng Zhang Fenglei Huang 《Defence Technology(防务技术)》 2025年第6期268-283,共16页
DNAN-based insensitive melt-cast explosives have been widely utilized in insensitive munition in recent years. When constrained DNAN-based melt-cast explosives are ignited under thermal stimulation, the base explosive... DNAN-based insensitive melt-cast explosives have been widely utilized in insensitive munition in recent years. When constrained DNAN-based melt-cast explosives are ignited under thermal stimulation, the base explosive exists in a molten liquid state, where high-temperature gases expand and react in the form of bubble clouds within the liquid explosive;this process is distinctly different from the dynamic crack propagation process observed in the case of solid explosives. In this study, a control model for the reaction evolution of burning-bubble clouds was established to describe the reaction process and quantify the reaction violence of DNAN-based melt-cast explosives, considering the size distribution and activation mechanism of the burning-bubble clouds. The feasibility of the model was verified through experimental results. The results revealed that under geometrically similar conditions, with identical confinement strength and aspect ratio, larger charge structures led to extended initial gas flow and surface burning processes, resulting in greater reaction equivalence and violence at the casing fracture.Under constant charge volume and size, a stronger casing confinement accelerated self-enhanced burning, increasing the internal pressure, reaction degree, and reaction violence. Under a constant casing thickness and radius, higher aspect ratios led to a greater reaction violence at the casing fracture.Moreover, under a constant charge volume and casing thickness, higher aspect ratios resulted in a higher internal pressure, increased reaction degree, and greater reaction violence at the casing fracture. Further,larger ullage volumes extended the reaction evolution time and increased the reaction violence under constant casing dimensions. Through a matching design of the opening threshold of the pressure relief holes and the relief structure area, a stable burning reaction could be maintained until completion,thereby achieving a control of the reaction violence. The proposed model could effectively reflect the effects of the intrinsic burning rate, casing confinement strength, charge size, ullage volume, and pressure relief structure on the reaction evolution process and reaction violence, providing a theoretical method for the thermal safety design and reaction violence evaluation of melt-cast explosives. 展开更多
关键词 Melt-cast explosives Non-shock-initiated reaction Self-sustaining enhanced combustion Burning-bubble cloud model Pressure relief area Reaction violence
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A cloud model target damage effectiveness assessment algorithm based on spatio-temporal sequence finite multilayer fragments dispersion
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作者 Hanshan Li Xiaoqian Zhang Junchai Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期48-64,共17页
To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage p... To solve the problem of target damage assessment when fragments attack target under uncertain projectile and target intersection in an air defense intercept,this paper proposes a method for calculating target damage probability leveraging spatio-temporal finite multilayer fragments distribution and the target damage assessment algorithm based on cloud model theory.Drawing on the spatial dispersion characteristics of fragments of projectile proximity explosion,we divide into a finite number of fragments distribution planes based on the time series in space,set up a fragment layer dispersion model grounded in the time series and intersection criterion for determining the effective penetration of each layer of fragments into the target.Building on the precondition that the multilayer fragments of the time series effectively assail the target,we also establish the damage criterion of the perforation and penetration damage and deduce the damage probability calculation model.Taking the damage probability of the fragment layer in the spatio-temporal sequence to the target as the input state variable,we introduce cloud model theory to research the target damage assessment method.Combining the equivalent simulation experiment,the scientific and rational nature of the proposed method were validated through quantitative calculations and comparative analysis. 展开更多
关键词 Target damage cloud model Fragments dispersion Effectiveness assessment Spatio-temporal sequence
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Research on BIM Model Reshaping Method Based on 3D Point Cloud Recognition
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作者 SHI Jin-yu YU Xian-feng +1 位作者 SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期125-135,共11页
In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technolog... In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technology and BIM(Building Information Modeling)model was discussed.Focused on the efficient acquisition of building geometric information using the fast-developing 3D point cloud technology,an improved deep learning-based 3D point cloud recognition method was proposed.The method optimised the network structure based on RandLA-Net to adapt to the large-scale point cloud processing requirements,while the semantic and instance features of the point cloud were integrated to significantly improve the recognition accuracy and provide a precise basis for BIM model remodeling.In addition,a visual BIM model generation system was developed,which systematically transformed the point cloud recognition results into BIM component parameters,automatically constructed BIM models,and promoted the open sharing and secondary development of models.The research results not only effectively promote the automation process of converting 3D point cloud data to refined BIM models,but also provide important technical support for promoting building informatisation and accelerating the construction of smart cities,showing a wide range of application potential and practical value. 展开更多
关键词 3D point cloud RandLA-Net network BIM model OSG engine
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Flatness predictive model based on T-S cloud reasoning network implemented by DSP 被引量:4
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作者 ZHANG Xiu-ling GAO Wu-yang +1 位作者 LAI Yong-jin CHENG Yan-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2222-2230,共9页
The accuracy of present flatness predictive method is limited and it just belongs to software simulation. In order to improve it, a novel flatness predictive model via T-S cloud reasoning network implemented by digita... The accuracy of present flatness predictive method is limited and it just belongs to software simulation. In order to improve it, a novel flatness predictive model via T-S cloud reasoning network implemented by digital signal processor(DSP) is proposed. First, the combination of genetic algorithm(GA) and simulated annealing algorithm(SAA) is put forward, called GA-SA algorithm, which can make full use of the global search ability of GA and local search ability of SA. Later, based on T-S cloud reasoning neural network, flatness predictive model is designed in DSP. And it is applied to 900 HC reversible cold rolling mill. Experimental results demonstrate that the flatness predictive model via T-S cloud reasoning network can run on the hardware DSP TMS320 F2812 with high accuracy and robustness by using GA-SA algorithm to optimize the model parameter. 展开更多
关键词 T-S cloud reasoning neural NETWORK cloud model FLATNESS predictive model hardware implementation digital signal PROCESSOR genetic ALGORITHM and simulated annealing ALGORITHM (GA-SA)
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Cloud model-clustering analysis based evaluation for ventilation system of underground metal mine in alpine region 被引量:6
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作者 YAN Fang LI Zi-jun +4 位作者 DONG Long-jun HUANG Rui CAO Ri-hong GE Ji XU Kai-li 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期796-815,共20页
Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation sy... Ventilation system is significant in underground metal mine of alpine region.Reasonable evaluation of ventilation effectiveness will lead to a practical improvement for the maintenance and management of ventilation system.However,it is difficult to make an effective evaluation of ventilation system due to the lack of classification criteria with respect to underground metal mine in alpine region.This paper proposes a novel evaluation method called the cloud model-clustering analysis(CMCA).Cloud model(CM)is utilized to process collected data of ventilation system,and they are converted into cloud descriptors by CM.Cloud similarity(CS)based Euclidean distance(ED)is proposed to make clustering analysis of assessed samples.Then the classification of assessed samples will be identified by clustering analysis results.A case study is developed based on CMCA.Evaluation results show that ventilation effectiveness can be well classified.Moreover,CM is used alone to make comparison of evaluation results obtained by CMCA.Then the availability and validity of CMCA is verified.Meanwhile,difference of CS based ED and classical ED is analyzed.Two new clustering analysis methods are introduced to make comparison with CMCA.Then the ability of proposed CMCA to meet evaluation requirements of ventilation system is verified. 展开更多
关键词 ventilation system underground metal mine alpine region cloud model cloud similarity Euclidean distance
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CT-CloudDetect:用于遥感卫星云检测的混合模型
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作者 方巍 陶恩屹 《遥感信息》 CSCD 北大核心 2024年第5期1-11,共11页
云检测是在遥感卫星云图中检测云的任务。近年来,人们提出了基于深度学习的云检测方法,并取得了良好的性能。然而,现有的基于深度学习的云检测模型大多还是基于卷积神经网络(convolutional neural network,CNN),由于卷积运算的固有局部... 云检测是在遥感卫星云图中检测云的任务。近年来,人们提出了基于深度学习的云检测方法,并取得了良好的性能。然而,现有的基于深度学习的云检测模型大多还是基于卷积神经网络(convolutional neural network,CNN),由于卷积运算的固有局部性,难以捕获长距离依赖关系。针对上述问题,文章提出一个基于CNN和ViT(Vision Transformer)的混合型云检测模型,并提出一种基于CNN和ViT的编码器,使网络具备捕捉局部和全局信息的能力。为了更好地融合语义和尺度不一致的特征,提出了一个双尺度注意力融合模块,通过注意力机制有选择地融合特征。此外,提出了轻量级路由解码器,该解码器通过路由结构降低模型复杂度。在3个公开云检测数据集上对模型进行了评估。大量实验表明,所提出的模型具有比现有模型更好的性能。 展开更多
关键词 深度学习 卷积神经网络 空间Vision Transformer 混合模型 云检测
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Building a Tax Predictive Model Based on the Cloud Neural Network
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作者 田永青 李志 朱仲英 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第3期81-86,共6页
Tax is very important to the whole country, so a scientific tax predictive model is needed. This paper introduces the theory of the cloud model. On this basis, it presents a cloud neural network, and analyzes the main... Tax is very important to the whole country, so a scientific tax predictive model is needed. This paper introduces the theory of the cloud model. On this basis, it presents a cloud neural network, and analyzes the main factors which influence the tax revenue. Then if proposes a tax predictive model based on the cloud neural network. The model combines the strongpoints of the cloud model and the neural network. The experiment and simulation results show the effectiveness of the algorithm in this paper. 展开更多
关键词 cloud model Simplified TS cloud inference Neural network Tax predictive model.
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基于CloudSim的电力系统计算云原生模型与仿真方法 被引量:3
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作者 陈元榉 刘媛媛 +3 位作者 张延旭 蔡煜 胡春潮 蔡泽祥 《电力自动化设备》 EI CSCD 北大核心 2024年第9期189-196,204,共9页
分析基于云计算的电力系统计算过程是实现资源高效利用的基础。因此,提出一种基于CloudSim的电力系统计算的云原生建模与仿真方法。基于云原生技术阐述了电力系统计算架构的关键要素,提出基于CloudSim的电力系统计算架构的云原生模型,... 分析基于云计算的电力系统计算过程是实现资源高效利用的基础。因此,提出一种基于CloudSim的电力系统计算的云原生建模与仿真方法。基于云原生技术阐述了电力系统计算架构的关键要素,提出基于CloudSim的电力系统计算架构的云原生模型,分析电力云任务调配时的资源供需平衡问题。建立基于微服务的电力云任务模型,分析微服务的处理时序逻辑及其层级关系并生成微服务队列。据此提出微服务的动态调配模型,采用微服务-容器映射策略与实体动态整合策略,实现微服务在实体间的动态映射。利用CloudSim进行仿真分析,结果证明所提方法可行且有效,可为电力云计算的资源配置、任务调度等提供基本的仿真工具与方法。 展开更多
关键词 电力系统 cloudSim 云原生建模 电力系统计算架构 动态调配 时序逻辑 微服务队列
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Risk transmission evaluation for parallel construction of warships based on IFCM and the cloud model
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作者 GONG Jun HU Tao YAO Lu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第6期1224-1237,共14页
To cope with multi-directional transmission coupling,spreading, amplification, and chain reaction of risks during multiproject parallel construction of warships, a risk transmission evaluation method is proposed, whic... To cope with multi-directional transmission coupling,spreading, amplification, and chain reaction of risks during multiproject parallel construction of warships, a risk transmission evaluation method is proposed, which integrates an intuitionistic cloud model with a fuzzy cognitive map. By virtue of expectancy Ex, entropy En, and hyper entropy He, the risk fuzziness and randomness of the knowledge of experts are organically combined to develop a method for converting bi-linguistic variable decision-making information into the quantitative information of the intuitionistic normal cloud(INC) model. Subsequently, the threshold function and weighted summation operation in the traditional fuzzy cognitive map is converted into the INC ordered weighted averaging operator to create the risk transmission model based on the intuitionistic fuzzy cognitive map(IFCM) and the algorithm for solving it. Subsequently, the risk influence sequencing method based on INC and the risk rating method based on nearness are proposed on the basis of Monte Carlo simulation in order to realize the mutual conversion of the qualitative and quantitative information in the risk evaluation results.Example analysis is presented to verify the effectiveness and practicality of the methods. 展开更多
关键词 risk evaluation multi-project parallel intuitionistic fuzzy cognitive map(IFCM) intuitionistic normal cloud(INC)model warship construction.
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Cloudless-Training:基于serverless的高效跨地域分布式ML训练框架
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作者 谭文婷 吕存驰 +1 位作者 史骁 赵晓芳 《高技术通讯》 CAS 北大核心 2024年第3期219-232,共14页
跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性... 跨地域分布式机器学习(ML)训练能够联合多区域的云资源协作训练,可满足许多新兴ML场景(比如大型模型训练、联邦学习)的训练需求。但其训练效率仍受2方面挑战的制约。首先,多区域云资源缺乏有效的弹性调度,这会影响训练的资源利用率和性能;其次,模型跨地域同步需要在广域网(WAN)上高频通信,受WAN的低带宽和高波动的影响,会产生巨大通信开销。本文提出Cloudless-Training,从3个方面实现高效的跨地域分布式ML训练。首先,它基于serverless计算模式实现,使用控制层和训练执行层的2层架构,支持多云区域的弹性调度和通信。其次,它提供一种弹性调度策略,根据可用云资源的异构性和训练数据集的分布自适应地部署训练工作流。最后,它提供了2种高效的跨云同步策略,包括基于梯度累积的异步随机梯度下降(ASGD-GA)和跨云参数服务器(PS)间的模型平均(MA)。Cloudless-Training是基于OpenFaaS实现的,并被部署在腾讯云上评估,实验结果表明Cloudless-Training可显著地提高跨地域分布式ML训练的资源利用率(训练成本降低了9.2%~24.0%)和同步效率(训练速度最多比基线快1.7倍),并能保证模型的收敛精度。 展开更多
关键词 跨地域分布式机器学习(ML)训练 跨云ML训练 分布式训练框架 serverless 跨云模型同步
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激光三维点云在岩性语义分割中的应用综述 被引量:1
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作者 邵燕林 刘浪 +4 位作者 曾齐红 胡忠贵 魏薇 邓帆 王庆 《科学技术与工程》 北大核心 2025年第4期1313-1324,共12页
激光三维扫描技术可快速获取扫描目标表面的点云数据,包括用于描述目标几何特征的空间点坐标和刻画目标材质反射率信息的激光反射强度。将激光三维点云的自动语义分割技术应用于地质勘探研究中,能为区域地质特征描绘奠定基础。为了展示... 激光三维扫描技术可快速获取扫描目标表面的点云数据,包括用于描述目标几何特征的空间点坐标和刻画目标材质反射率信息的激光反射强度。将激光三维点云的自动语义分割技术应用于地质勘探研究中,能为区域地质特征描绘奠定基础。为了展示激光三维扫描技术在地质场景大规模语义分割领域的最新进展,首先对摄影测量和激光雷达两种三维点云获取方式进行了比较,得到激光雷达在精度、泛用性、不易受光照条件影响等方面具有优势。通过阐述岩性语义分割的原理,将近年来基于几何特征或强度特征的岩性点云分割方法进行了全面的归纳和总结;介绍了常用大规模点云数据集和评价指标,并比较不同算法分割性能;最后总结了现有方法的局限性,并指出岩性语义分割任务未来研究方向进行展望。 展开更多
关键词 三维激光雷达 数字模型 点云语义分割 岩性分类
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基于代理生成对抗网络的服务质量感知云API推荐系统投毒攻击 被引量:1
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作者 陈真 刘伟 +3 位作者 吕瑞民 马佳洁 冯佳音 尤殿龙 《通信学报》 北大核心 2025年第3期174-186,共13页
针对现有投毒攻击方法生成的虚假用户攻击数据存在攻击效果差且易被检测的不足,提出一种基于代理生成对抗网络的投毒攻击方法。首先,在生成对抗网络中采用K-means算法将数据分类,并引入自注意力机制学习每个类中的全局特征,解决生成对... 针对现有投毒攻击方法生成的虚假用户攻击数据存在攻击效果差且易被检测的不足,提出一种基于代理生成对抗网络的投毒攻击方法。首先,在生成对抗网络中采用K-means算法将数据分类,并引入自注意力机制学习每个类中的全局特征,解决生成对抗网络在数据稀疏时难以有效捕捉真实用户复杂行为模式这一问题,提升虚假用户的隐蔽性。其次,引入代理模型评估生成对抗网络生成的虚假用户的攻击效果,将评估结果作为代理损失优化生成对抗网络,进而实现在兼顾虚假用户隐蔽性的同时增强攻击效果。云API服务质量数据集上的实验表明,所提方法在兼顾攻击的有效性和隐蔽性方面均优于现有方法。 展开更多
关键词 推荐系统 云API 投毒攻击 生成对抗网络 代理模型
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青藏高原公路低生态影响评价与决策方法 被引量:1
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作者 李涛 张宏 +3 位作者 徐鑫 曹升亮 张驰 杨宏志 《生态学报》 北大核心 2025年第8期3733-3749,共17页
公路建设在推动区域经济和社会发展的同时,也对生态环境产生了诸如生境干扰和水土流失加剧等负面影响。为在公路规划设计阶段进行源头生态保护,弥补路线方案决策时生态约束考虑不足和相近决策结果难抉择等问题,通过预测路域生态系统服... 公路建设在推动区域经济和社会发展的同时,也对生态环境产生了诸如生境干扰和水土流失加剧等负面影响。为在公路规划设计阶段进行源头生态保护,弥补路线方案决策时生态约束考虑不足和相近决策结果难抉择等问题,通过预测路域生态系统服务功能的变化,同时考虑路线方案占用生态敏感区的面积,建立了公路低生态影响评价指标体系,包括路线方案经过多年冻土和中厚层季节性冻土的面积、路线方案占用草地和林地面积、路域生境质量变化、路域水源涵养量变化、路域土壤侵蚀量变化。建立多维多规则云模型对路线方案进行评价和决策,并在久马高速上进行了实例应用,结果表明通过优化路线方案、以桥隧代路、完善边坡防护、复垦临时占地等方式能够降低路线工程对生态系统的扰动。研究提出了公路低生态影响评价与决策方法,有助于实现从事后恢复生态环境向事前规划和保护的转变,为公路设计优化、生态风险监测与管理、生态保护政策制定等方面提供决策支持,促进区域生态保护和高质量发展。 展开更多
关键词 环境保护与可持续发展 公路生态影响 公路决策 生态系统服务功能 云模型
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基于PSR+云模型的室内地震应急避难场所的韧性评估 被引量:1
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作者 李海凌 刘睿玲 张怀 《地震工程学报》 北大核心 2025年第1期143-151,共9页
为评估室内地震应急避难场所的韧性等级,提出一种基于压力-状态-响应(PSR)模型+云模型的室内地震应急避难场所韧性评估方法。从PSR角度构建室内地震应急避难场所韧性评估指标体系,划分韧性评估等级标准,利用AHP-DEMATEL为指标赋权,并结... 为评估室内地震应急避难场所的韧性等级,提出一种基于压力-状态-响应(PSR)模型+云模型的室内地震应急避难场所韧性评估方法。从PSR角度构建室内地震应急避难场所韧性评估指标体系,划分韧性评估等级标准,利用AHP-DEMATEL为指标赋权,并结合云模型构建室内地震应急避难场所的韧性评估模型。以该模型对绵阳市九洲体育馆进行实证分析,分别确定其压力韧性、状态韧性、响应韧性的隶属度等级,最终得到综合等级C 2的结论,与九洲体育馆在汶川地震中表现出的韧性状态吻合,验证了模型的有效性。 展开更多
关键词 韧性评估 室内地震应急避难场所 避难建筑 PSR模型 云模型
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电化学储能电站运行风险评价模型与应用研究 被引量:1
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作者 陈西江 毛晓萱 胡少华 《安全与环境学报》 北大核心 2025年第4期1257-1266,共10页
为提升电化学储能电站风险管控水平和本质安全能力,研究基于等级全息模型(Hierarchical Holographic Modeling,HHM)建立电化学储能电站运行风险评价指标体系,包括人员因素、电池因素、环境因素、管理因素4个一级指标,以及壳体破损、荷... 为提升电化学储能电站风险管控水平和本质安全能力,研究基于等级全息模型(Hierarchical Holographic Modeling,HHM)建立电化学储能电站运行风险评价指标体系,包括人员因素、电池因素、环境因素、管理因素4个一级指标,以及壳体破损、荷电状态等20个二级指标。运用最优最劣法(Best-Worst Method,BWM)和改进CRITIC(Criteria Importance Through Intercriteria Correlation)法确定评价指标的主客观权重,利用博弈论方法计算评价指标的组合权重,并应用二维云模型通过仿真分析确定风险指标等级,构建了基于BWM-改进CRITIC-二维云模型的电化学储能电站运行风险评价模型。工程应用结果显示:永川松溉储能电站运行风险等级为Ⅲ级,处于一般风险。该电站电池荷电状态和单体间温度不一致的概率等级、后果等级风险云数字特征较高,分别为5.05、6.58和5.87、5.78,二者在风险管控中应处于核心地位。 展开更多
关键词 安全工程 储能电站 风险评价 二维云模型
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基于无人机MiniSAR和多光谱遥感数据的冬小麦土壤墒情反演 被引量:1
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作者 张成才 祝星星 +2 位作者 姜明梁 王蕊 侯佳彤 《节水灌溉》 北大核心 2025年第3期105-112,共8页
为了去除农作物对雷达散射信号的影响,探究不同极化方式土壤后向散射系数与土壤墒情的响应关系,实现对冬小麦农田土壤墒情的精准监测,基于无人机MiniSAR多极化数据和多光谱数据,提出联合改进水云模型与BP神经网络反演土壤墒情的方法。... 为了去除农作物对雷达散射信号的影响,探究不同极化方式土壤后向散射系数与土壤墒情的响应关系,实现对冬小麦农田土壤墒情的精准监测,基于无人机MiniSAR多极化数据和多光谱数据,提出联合改进水云模型与BP神经网络反演土壤墒情的方法。首先利用植被覆盖度对水云模型进行改进,提取不同极化方式下的土壤后向散射系数,通过设置不同极化方式、极化差、极化比数据与归一化植被指数(NDVI)的多种组合模式,输入BP神经网络,构建冬小麦土壤墒情反演模型,并以河南省鹤壁市浚县中部的冬小麦种植区为试验区分析模型的预测效果。结果表明:相比于冬小麦土壤墒情线性回归模型,基于BP神经网络的土壤墒情反演模型精度更高,其中由改进水云模型计算得到的VV极化下的土壤后向散射系数、HH极化下的土壤后向散射系数以及两者的极化差、极化比组合输入BP神经网络得到的反演结果精度最高,R^(2)达到0.767,MAE为0.0136cm^(3)/cm^(3),RMSE为0.0176cm^(3)/cm^(3)。表明联合改进水云模型与BP神经网络的冬小麦土壤墒情反演模型具有较高的反演精度,为准确监测冬小麦土壤墒情提供了一种新思路。 展开更多
关键词 土壤墒情 水云模型 BP神经网络 后向散射系数 MiniSAR数据
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具有灵活性的指定验证者云审计方案
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作者 赵巨涛 常金勇 《计算机应用与软件》 北大核心 2025年第4期335-339,共5页
在最近的研究工作中,Yan等[13]设计了一个具有指定验证者的云审计协议。研究发现,Yan等的协议具有很高的通信冗余。为了降低这一通信冗余,提出一种具有灵活性的改进方案,该方案将多个数据段对应的标签进行“聚合”,从而可以极大地减少... 在最近的研究工作中,Yan等[13]设计了一个具有指定验证者的云审计协议。研究发现,Yan等的协议具有很高的通信冗余。为了降低这一通信冗余,提出一种具有灵活性的改进方案,该方案将多个数据段对应的标签进行“聚合”,从而可以极大地减少通信冗余。同时,基于计算性的Diffie-Hellman假设给出了改进方案的安全性证明。通过具体实例展示了改进后的方案在整体通信冗余上比Yan等的协议有明显降低。 展开更多
关键词 云审计方案 指定验证者 随机谕言机模型 云存储
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滑坡涌浪危险性云模型及其应用研究
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作者 牟萍 王平义 +2 位作者 韩林峰 喻涛 张帆 《重庆交通大学学报(自然科学版)》 北大核心 2025年第5期81-87,共7页
滑坡涌浪灾害作为一种突发性自然灾害,其预测与防护是工程中需研究的重要问题。笔者在涌浪成因机理分析基础上,基于滑坡体规模、坡形、岩性、高度、水面宽度、水深和河道特征等7个影响因子的滑坡涌浪危险性指标体系,构建了滑坡涌浪危险... 滑坡涌浪灾害作为一种突发性自然灾害,其预测与防护是工程中需研究的重要问题。笔者在涌浪成因机理分析基础上,基于滑坡体规模、坡形、岩性、高度、水面宽度、水深和河道特征等7个影响因子的滑坡涌浪危险性指标体系,构建了滑坡涌浪危险性评价云模型,并将该云模型应用于三峡库区3组典型滑坡案例。结果表明:云模型理论可用于研究滑坡涌浪灾害危险性;三峡库区典型滑坡涌浪灾害的危险程度处于中等和较高之间;应对库区潜在滑坡体进行实时监测预警,并采取相应的措施。 展开更多
关键词 港口与航道工程 滑坡涌浪 危险性 云模型 指标体系
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基于组合赋权—云模型的海绵城市韧性水平研究
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作者 何伟军 曹东杰 +1 位作者 袁亮 孔阳 《生态经济》 北大核心 2025年第5期81-89,126,共10页
在全球气候变化和快速城市化的背景下,增强城市韧性是实现城市可持续发展的必然要求。海绵城市作为一种新型的城市发展模式,探究其韧性发展水平对我国韧性城市建设具有重要意义。论文将韧性理念与海绵城市建设相结合,综合运用组合赋权... 在全球气候变化和快速城市化的背景下,增强城市韧性是实现城市可持续发展的必然要求。海绵城市作为一种新型的城市发展模式,探究其韧性发展水平对我国韧性城市建设具有重要意义。论文将韧性理念与海绵城市建设相结合,综合运用组合赋权、云模型等评估海绵城市建设试点2015—2022年城市韧性水平变化。结果表明:(1)试点城市的城市韧性指数均呈波动上升趋势,城市韧性水平持续提升但发展不均衡,个体差异较大,表现出明显的阶梯分布特征;(2)试点城市的城市韧性存在显著的空间差异性,城市韧性水平表现出“东部>中部>西部>东北”的特征,城市韧性增速表现出“西部>中部>东部>东北”的特征;(3)试点城市的整体韧性等级不断提升,总体由“低韧性”发展为“中韧性”,但仍处于较低等级。各子系统韧性等级也有不同程度的提升,生态韧性提升效果最好,经济韧性提升效果一般。论文不仅评估了我国海绵城市的城市韧性发展水平,而且提出了加强海绵城市韧性建设的对策建议。 展开更多
关键词 海绵城市 城市韧性 组合赋权 云模型 可持续发展
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