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Stability analysis of discrete-time BAM neural networks based on standard neural network models 被引量:1
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作者 张森林 刘妹琴 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期689-696,共8页
To facilitate stability analysis of discrete-time bidirectional associative memory (BAM) neural networks, they were converted into novel neural network models, termed standard neural network models (SNNMs), which inte... To facilitate stability analysis of discrete-time bidirectional associative memory (BAM) neural networks, they were converted into novel neural network models, termed standard neural network models (SNNMs), which interconnect linear dynamic systems and bounded static nonlinear operators. By combining a number of different Lyapunov functionals with S-procedure, some useful criteria of global asymptotic stability and global exponential stability of the equilibrium points of SNNMs were derived. These stability conditions were formulated as linear matrix inequalities (LMIs). So global stability of the discrete-time BAM neural networks could be analyzed by using the stability results of the SNNMs. Compared to the existing stability analysis methods, the proposed approach is easy to implement, less conservative, and is applicable to other recurrent neural networks. 展开更多
关键词 standard neural network model (SNNM) Bidirectional associative memory (BAM) Linear matrix inequality (LMI) STABILITY Generalized eigenvalue problem (GEVP)
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Interval standard neural network models for nonlinear systems
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作者 LIU Mei-qin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期530-538,共9页
A neural-network-based robust control design is suggested for control of a class of nonlinear systems. The design ap- proach employs a neural network, whose activation functions satisfy the sector conditions, to appro... A neural-network-based robust control design is suggested for control of a class of nonlinear systems. The design ap- proach employs a neural network, whose activation functions satisfy the sector conditions, to approximate the nonlinear system. To improve the approximation performance and to account for the parameter perturbations during operation, a novel neural network model termed standard neural network model (SNNM) is proposed. If the uncertainty is bounded, the SNNM is called an interval SNNM (ISNNM). A state-feedback control law is designed for the nonlinear system modelled by an ISNNM such that the closed-loop system is globally, robustly, and asymptotically stable. The control design equations are shown to be a set of linear matrix inequalities (LMIs) that can be easily solved by available convex optimization algorithms. An example is given to illustrate the control design procedure, and the performance of the proposed approach is compared with that of a related method reported in literature. 展开更多
关键词 Interval standard neural network model (ISNNM) Linear matrix inequality (LMI) Nonlinear system Asymptotic stability Robust control
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Challenges of the Performance Standards of the International Finance Corporation in Financing the African Integrated High-Speed Railway Network and the Way Forward: The Case of Standard Gauge Railway in Tanzania
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作者 Emmanuele Elifadhili Mchome Uwezo Wilbard Nzoya 《Journal of Transportation Technologies》 2023年第4期772-788,共17页
Financing of the African Integrated High-Speed Railway Network (AIHSRN) through Standard Gauge Railway (SGR) Projects is very expensive. As a result, most of the African countries seek financial supports from the Inte... Financing of the African Integrated High-Speed Railway Network (AIHSRN) through Standard Gauge Railway (SGR) Projects is very expensive. As a result, most of the African countries seek financial supports from the International Financial Institutions (IFIs). However, conditions provided by the IFIs through the Performance Standards (PS) of the International Financial Corporation (IFC) increase cost of the projects and thus, it becomes a burden to most of the African countries. This study aimed to explore the causes of IFC-PS through the SGR Projects that escalate costs and how to address them. The Tanzania SGR Lot 1 Project that covered 205 km from Dar es Salaam to Morogoro was selected as a case study. The methods used for data collection involved literature review, focus group discussions and interviews. The results and findings show a gap between the IFC-PS and the National Laws and Regulations that escalates costs of the projects if funds from the IFIs were to be secured. To bridge the gap, it is recommended that the African countries should engage into negotiations with the IFIs to agree to waive IFC-PS conditions that escalate costs provided they are adequately covered in the national laws and regulations;engagement of locally established national and regional financial institutions;and the responsible government institutions in the African countries should sit together for assessment and review of the IFC-PS against the national laws and regulations. 展开更多
关键词 African Integrated High-Speed Railway network International Financial Institutions standard Gauge Railway Performance standards
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Development of an Ontology-Based Knowledge Network by Interconnecting Soil/Water Concepts/Properties, Derived from Standards Methods and Published Scientific References Outlining Infiltration/Percolation Process of Contaminated Water 被引量:1
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作者 Stephanos D. V. Giakoumatos Anastasios K. T. Gkionakis 《Journal of Geoscience and Environment Protection》 2021年第1期25-52,共28页
The present work deals with the development of an Ontology-Based Knowledge Network of soil/water physicochemical & biological properties (soil/water concepts), derived from ASTM Standard Methods (ASTMi,n) and rele... The present work deals with the development of an Ontology-Based Knowledge Network of soil/water physicochemical & biological properties (soil/water concepts), derived from ASTM Standard Methods (ASTMi,n) and relevant scientific/applicable references (published papers—PPi,n) to fill up/bridge the gap of the information science between cited Standards and infiltration discipline conceptual vocabulary providing accordingly a dedicated/internal Knowledge Base (KB). This attempt constitutes an innovative approach, since it is based on externalizing domain knowledge in the form of Ontology-Based Knowledge Networks, incorporating standardized methodology in soil engineering. The ontology soil/water concepts (semantics) of the developed network correspond to soil/water physicochemical & biological properties, classified in seven different generations that are distinguished/located in infiltration/percolation process of contaminated water through soil porous media. The interconnections with arcs between corresponding concepts/properties among the consecutive generations are defined by the relationship of dependent and independent variables. All these interconnections are documented according to the below three ways: 1) dependent and independent variables interconnected by using the logical operator “<em>depends on</em>” quoting existent explicit functions and equations;2) dependent and independent variables interconnected by using the logical operator “<em>depends on</em>” quoting produced implicit functions, according to Rayleigh’s method of indices;3) dependent and independent variables interconnected by using the logical operator “<em>related to</em>” based on a logical dependence among the examined nodes-concepts-variables. The aforementioned approach provides significant advantages to semantic web developers and web users by means of prompt knowledge navigation, tracking, retrieval and usage. 展开更多
关键词 INFILTRATION PERCOLATION ASTM standards Soil/Water Contamination Knowledge Base Ontology network Semantics Porous Media
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Strategy Selection of Production Technical Standards in a Manufacturing Supply Chain Network: The Role of Partnership Density
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作者 ZHANG Huiying LI Zhendong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第6期517-522,共6页
This paper presents the game of production technical standards between downstream and upstream suppliers on a manufacturing supply chain network when the two parties have different partnership densities, namely, the n... This paper presents the game of production technical standards between downstream and upstream suppliers on a manufacturing supply chain network when the two parties have different partnership densities, namely, the numbers of replaceable and mature manufacturing partners. We firstly constructed a manufacturing chain network and analyzed its three relationship structures among suppliers with the presence of different relationship densities, and found that all the three relationships brought about the game of production technical standards between partnership-rich and partnership-scanty suppliers. Then we built a two-party payoff matrix, and analyzed the two-party game and evolutionary stable strategy, based on replication dynamic equation and asymmetric evolutionary game theory. The evolutionary stable strategies of two parties under varying payoff parameters were validated through numerical simulation. Finally, we proposed some suggestions for both those manufacturers with more partners and fewer partners, respectively. 展开更多
关键词 production technical standard asymmetric game partnership density manufacturing supply chain network
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基于绿氢配额机制的多氢系统-掺氢管网协同运行研究
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作者 江岳文 黄筱翊 李镇杭 《电网技术》 北大核心 2026年第2期576-587,I0046-I0050,共17页
该文针对氢系统与掺氢天然气管网的协同运行问题,兼顾二者经济效益、碳减排效益及运行安全,设计与源端绿电供给潜力相关的绿氢配额机制,包括年配额指标的分解方法、实际绿氢消纳量及绿氢证书数量的计算规则,以引导掺氢管网完成终端绿氢... 该文针对氢系统与掺氢天然气管网的协同运行问题,兼顾二者经济效益、碳减排效益及运行安全,设计与源端绿电供给潜力相关的绿氢配额机制,包括年配额指标的分解方法、实际绿氢消纳量及绿氢证书数量的计算规则,以引导掺氢管网完成终端绿氢消纳任务,促进可再生能源消纳与氢产业的发展。上层模型以多氢系统经济效益最大化与促进可再生能源消纳为目标,采用离网风电与电网电力相结合的制氢方式,各氢系统虽独立完成制氢、储氢和供氢过程,但通过聚合机制将各氢系统进行统一管理,由氢系统聚合商集中优化购电、制绿氢及储氢策略;下层模型以掺氢管网购气成本最小化为目标,结合气体热值、动态掺氢比例及管网运行安全约束等,设计基于流向判断的掺氢比例迭代更新机制及热值更新方法,优化购气策略。考虑多运营主体间的数据隐私需求,引入交替方向乘子法求解。最后,基于某工业园区内由一个多氢系统聚合体与20节点掺氢天然气管网组成的系统进行仿真,验证所提模型的合理性以及方法的可行性。 展开更多
关键词 多氢系统 掺氢管网 绿氢配额机制 协同运行
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关于在LAN环境中应用IEEE 802.1X Standard的安全性分析 被引量:3
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作者 赖炜 钱骏 《现代计算机》 2003年第4期51-53,87,共4页
本文对在LAN环境中实施IEEE802.1X协议的安全性作了一个初步的分析,并着重研究了基于802.11协议的无线网与802.1X协议的结合应用。在此基础上,分析了IEEE802.1X Standard内在的安全缺陷,提出了相应的解决方法。
关键词 LAN 局域网 计算机网络 IEEE802.1X协议 安全性
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生态环境标准提升、产业关联与全产业链绿色转型——基于生产网络的视角
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作者 丁辰鑫 孙慧 +1 位作者 王芝炜 张贤峰 《南方经济》 北大核心 2026年第2期92-116,共25页
以国家标准提升引领传统产业优化升级是推动经济社会发展全面绿色转型的具体举措,如何更有效地发挥环境标准对全产业链绿色转型的带动效应在当前阶段尤其值得关注。文章基于生产网络视角,通过构建企业在环保约束下的生产设备选择模型,... 以国家标准提升引领传统产业优化升级是推动经济社会发展全面绿色转型的具体举措,如何更有效地发挥环境标准对全产业链绿色转型的带动效应在当前阶段尤其值得关注。文章基于生产网络视角,通过构建企业在环保约束下的生产设备选择模型,从理论上分析了环境标准提升对代表性企业生产设备选择的影响,以及不同的设备更新方式(外部购置或自主创新)如何带动上下游关联行业的生产变革,并最终带动全产业链的绿色转型。在此基础上,将2004—2014年的水污染排放标准提升作为一项准自然实验,通过构造省级4位数行业层面的生产网络进行了实证检验。结果表明,水污染排放标准的分批次提升不仅能在不减产的前提下促进规制行业的COD减少,还能协同减少关联行业的COD,实现全产业链的绿色转型。水污染排放标准提升引发了规制行业的技术创新、生产设备和污染治理设备更新,且对不同产业链位置的关联行业的减排存在非对称影响:(1)设备购买诱发了上游设备行业的自主创新,并协同减少了其COD;(2)水污染标准提升的压力和知识溢出的辅力共同推动下游行业通过创新、增加生产设备和污染治理设备购买实现了COD减排;(3)水污染标准提升的压力在平均意义上未能有效降低上游原材料行业的COD,仅当标准提升幅度较大时,或与被国家和地方共同关注的行业关联时才存在减排效应。进一步,利用上市公司数据再次检验2015年后新一轮水污染排放标准提升的效果,新一轮标准提升对不同产业链位置关联企业的绿色转型均有显著的带动效应。文章从产业链溢出视角丰富了环境标准推动产业绿色转型的经验证据,可为环境标准规制对象的扩围和限值提升幅度的选择提供依据,也可为树立产业链治理思维提供参考。 展开更多
关键词 生态环境标准 水污染排放标准 生产网络 产业链溢出 绿色转型
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基于条件生成对抗网络和Vision Transformer的胎儿颅脑超声标准切面识别方法
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作者 李惠莲 林艺榕 +1 位作者 刘中华 柳培忠 《临床超声医学杂志》 2026年第2期164-169,共6页
胎儿颅脑超声检查是产前常规筛查中至关重要的一环,准确识别标准切面对于评估胎儿大脑发育状况具有重要意义。然而,由于超声图像质量差异和切面获取的复杂性,准确识别标准切面具有较大的挑战性。本文提出了一种基于条件对抗生成网络(CG... 胎儿颅脑超声检查是产前常规筛查中至关重要的一环,准确识别标准切面对于评估胎儿大脑发育状况具有重要意义。然而,由于超声图像质量差异和切面获取的复杂性,准确识别标准切面具有较大的挑战性。本文提出了一种基于条件对抗生成网络(CGAN)和Vision Transformer的胎儿颅脑超声标准切面识别方法,利用CGAN对原始数据进行增强,生成额外的标准切面和非标准切面图像,解决数据不足的问题;同时采用YOLOv9模型对超声图像中的颅骨区域进行自动裁剪,去除无关信息,确保模型专注于关键区域。在分类模型中采用Vision Transformer对所有输入图像进行归一化和尺寸调整,使用了数据增强技术如随机水平或垂直翻转、调整图像对比度、中心裁剪和调整图像饱和度等。结果显示,相较于现有最优模型CSwin Transformer的方法,本文提出的方法在胎儿颅脑超声标准切面识别任务中表现出色,其精确率、召回率、F1分数及准确率分别为92.5%、92.3%、92.4%和93.3%。该方法在提升识别精度方面具有显著优势,为临床超声检查提供了有效技术支持。 展开更多
关键词 条件生成对抗网络 Vision Transformer 颅脑超声 胎儿 标准切面识别方法
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胰腺神经内分泌肿瘤的临床诊疗——美国国家综合癌症网络临床实践指南(2025年第2版)解读
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作者 刘肖凤 田伯乐 《临床外科杂志》 2026年第1期22-25,共4页
本文对《美国国家综合癌症网络神经内分泌肿瘤临床实践指南(2025年第2版)》中胰腺神经内分泌肿瘤(pNENs)的相关内容进行系统解读。pNENs具有高度异质性,其临床管理需依托多学科协作模式。该指南体现了精准诊疗理念,通过整合病理分级、... 本文对《美国国家综合癌症网络神经内分泌肿瘤临床实践指南(2025年第2版)》中胰腺神经内分泌肿瘤(pNENs)的相关内容进行系统解读。pNENs具有高度异质性,其临床管理需依托多学科协作模式。该指南体现了精准诊疗理念,通过整合病理分级、分子特征及功能影像学实现诊断与风险分层。在治疗方面,倡导个体化策略:对局部疾病,手术决策应综合考量肿瘤大小、分级及病人整体状况;对晚期疾病,依据肿瘤生物学行为及特定分子靶点选择全身治疗方案。此外,指南重视遗传风险评估与长期随访管理,建议对特定病人进行遗传易感基因检测,并制定为期10年以上的规律随访计划。总体而言,该指南为pNENs的临床管理提供了系统化、基于循证医学的完整诊疗框架。 展开更多
关键词 胰腺神经内分泌肿瘤 美国国家综合癌症网络 临床指南 诊疗规范
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Considerations of treatment standardization from the procession of NCCN guideline of esophagealcancer 被引量:7
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作者 Xian-Shu Gao 《Chinese Journal of Cancer》 SCIE CAS CSCD 北大核心 2010年第10期860-864,共5页
Esophageal carcinoma is one of the most common malignant tumors, especially in China which is the high incidence area. As a result of mild symptoms of early-stage esophageal cancer, the majority of patients cannot be ... Esophageal carcinoma is one of the most common malignant tumors, especially in China which is the high incidence area. As a result of mild symptoms of early-stage esophageal cancer, the majority of patients cannot be diagnosed until they develop to advanced cancer, and the treatment outcome of surgery or chemoradiotherapy is still unsatisfactory at present. The guidelines of esophageal cancer issued by National Comprehensive Cancer Network (NCCN) are regarded as important reference tools by clinical oncologists, and provide uniform criteria for the diagnosis and treatment of esophageal carcinoma. However, the guidelines are not always suitable for Chinese patients because the data come from European and American population which have significant ethnical difference from Chinese. We retrospectively analyzed the changes of treatment strategy of esophageal cancer in NCCN guidelines and the advance of treatment for esophageal carcinoma in China, aiming to provide our oncologists with new research ideas. We also hope to set up clinical cancer cooperation organizations, and release our own cancer guidelines to serve Chinese patients and oncologists. 展开更多
关键词 治疗效果 食管癌 标准化 癌症患者 恶性肿瘤 民族差异 合作组织 肿瘤学
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高速公路路网运行监测与预警平台研发与应用
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作者 张佳鹏 《无线互联科技》 2026年第4期87-90,96,共5页
高速公路路网的智慧化运营是行业发展的核心方向,针对传统管理模式粗放、数据协同性差、应急处置效率低等痛点,文章构建了一套高速公路路网运行监测与预警平台。平台以全场景动态管控为目标,从数据标准、中间支撑、核心功能3个维度展开... 高速公路路网的智慧化运营是行业发展的核心方向,针对传统管理模式粗放、数据协同性差、应急处置效率低等痛点,文章构建了一套高速公路路网运行监测与预警平台。平台以全场景动态管控为目标,从数据标准、中间支撑、核心功能3个维度展开设计:制定路网编码、设备编码、数据接口及通信协议等标准,实现全路网数据的标准化接入;搭建图层管理、场景2D页面、视频流媒体、在线报表等中间支撑服务,夯实平台运行基础;开发监控态势、场景监测、视频监控、网络管理等核心功能模块,形成“场景精准监控—路段整体调度—省级宏观把控”的三级管控架构。该平台已在山西省中心及12个路段中心落地应用,实现了路网运行状态的全景化监测、风险隐患的提前预警、应急事件的高效协同处置,推动了高速公路运营管理从被动应对向主动预判转型,为路网智慧化运营提供了可行的解决方案。 展开更多
关键词 高速公路 路网监测 智慧管控 应急协同 数据标准
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低空运输路空协同新交通体系框架构建与深圳市实践
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作者 孙超 黄愉文 韩广广 《城市交通》 2026年第1期79-86,共8页
作为新质生产力的重要组成部分,低空经济正从飞行试验阶段加速迈向规模化商业应用。推进路空协同发展,对加强路空资源统筹与安全管控、提升综合立体交通网络整体效能、引领战略性新兴产业发展具有重要作用。从设施协同、管控协同、运营... 作为新质生产力的重要组成部分,低空经济正从飞行试验阶段加速迈向规模化商业应用。推进路空协同发展,对加强路空资源统筹与安全管控、提升综合立体交通网络整体效能、引领战略性新兴产业发展具有重要作用。从设施协同、管控协同、运营协同、服务协同与产业协同5个方面提出低空运输路空协同新交通体系框架,以支撑地面交通与低空交通的融合发展。在此基础上,结合低空运输发展实际,围绕时空融合感知、可计算空域底座、设施资源协同配置、全流程安全管控、多模式智能调度、政策标准体系完善等方面,系统阐述低空运输路空协同的发展思路,并以深圳市为例,提出覆盖设施建设、安全管控、调度服务、政策标准的全链条发展路径。 展开更多
关键词 低空经济 交通运输 路空协同 立体交通网络 智能调度 政策标准
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Robust exponential stability analysis of a larger class of discrete-time recurrent neural networks 被引量:1
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作者 ZHANG Jian-hai ZHANG Sen-lin LIU Mei-qin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第12期1912-1920,共9页
The robust exponential stability of a larger class of discrete-time recurrent neural networks (RNNs) is explored in this paper. A novel neural network model, named standard neural network model (SNNM), is introduced t... The robust exponential stability of a larger class of discrete-time recurrent neural networks (RNNs) is explored in this paper. A novel neural network model, named standard neural network model (SNNM), is introduced to provide a general framework for stability analysis of RNNs. Most of the existing RNNs can be transformed into SNNMs to be analyzed in a unified way. Applying Lyapunov stability theory method and S-Procedure technique, two useful criteria of robust exponential stability for the discrete-time SNNMs are derived. The conditions presented are formulated as linear matrix inequalities (LMIs) to be easily solved using existing efficient convex optimization techniques. An example is presented to demonstrate the transformation procedure and the effectiveness of the results. 展开更多
关键词 standard neural network model (SNNM) Robust exponential stability Recurrent neural networks (RNNs) DISCRETE-TIME Time-delay system Linear matrix inequality (LMI)
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LMI-based approach for global asymptotic stability analysis of continuous BAM neural networks 被引量:2
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作者 张森林 刘妹琴 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第1期32-37,共6页
Studies on the stability of the equilibrium points of continuous bidirectional associative memory (BAM) neural network have yielded many useful results. A novel neural network model called standard neural network mode... Studies on the stability of the equilibrium points of continuous bidirectional associative memory (BAM) neural network have yielded many useful results. A novel neural network model called standard neural network model (SNNM) is ad- vanced. By using state affine transformation, the BAM neural networks were converted to SNNMs. Some sufficient conditions for the global asymptotic stability of continuous BAM neural networks were derived from studies on the SNNMs’ stability. These conditions were formulated as easily verifiable linear matrix inequalities (LMIs), whose conservativeness is relatively low. The approach proposed extends the known stability results, and can also be applied to other forms of recurrent neural networks (RNNs). 展开更多
关键词 standard neural network model (SNNM) Bidirectional associative memory (BAM) neural network Linear matrix inequality (LMI) Linear differential inclusion (LDI) Global asymptotic stability
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Attribute-Based Re-Encryption Scheme in the Standard Model 被引量:4
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作者 GUO Shanqing ZENG Yingpei +1 位作者 WEI Juan XU Qiuliang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期621-625,共5页
In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext unde... In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext under another set of attributes on the same message, but not vice versa, furthermore, its security was proved in the standard model based on decisional bilinear Diffie-Hellman assumption. This scheme can be used to realize fine-grained selectively sharing of encrypted data, but the general proxy rencryption scheme severely can not do it, so the proposed schemecan be thought as an improvement of general traditional proxy re-encryption scheme. 展开更多
关键词 ATTRIBUTE-BASED re-encryption scheme standard model network storage
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Stability analysis of extended discrete-time BAMneural networks based on LMI approach
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作者 刘妹琴 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期588-594,共7页
We propose a new approach for analyzing the global asymptotic stability of the extended discrete-time bidirectional associative memory (BAM) neural networks. By using the Euler rule, we discretize the continuous-tim... We propose a new approach for analyzing the global asymptotic stability of the extended discrete-time bidirectional associative memory (BAM) neural networks. By using the Euler rule, we discretize the continuous-time BAM neural networks as the extended discrete-time BAM neural networks with non-threshold activation functions. Here we present some conditions under which the neural networks have unique equilibrium points. To judge the global asymptotic stability of the equilibrium points, we introduce a new neural network model - standard neural network model (SNNM). For the SNNMs, we derive the sufficient conditions for the global asymptotic stability of the equilibrium points, which are formulated as some linear matrix inequalities (LMIs). We transform the discrete-time BAM into the SNNM and apply the general result about the SNNM to the determination of global asymptotic stability of the discrete-time BAM. The approach proposed extends the known stability results, has lower conservativeness, can be verified easily, and can also be applied to other forms of recurrent neural networks. 展开更多
关键词 standard neural network model bidirectional associative memory DISCRETE-TIME linear matrix inequality global asymptotic stability.
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The development of brain functional connectivity networks revealed by resting-state functional magnetic resonance imaging 被引量:4
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作者 Chao-Lin Li Yan-Jun Deng +2 位作者 Yu-Hui He Hong-Chang Zhai Fu-Cang Jia 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第8期1419-1429,共11页
Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the... Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the independent components of activation and network connectivity between brain regions, we examined brain activity status and development trends in children aged 3 and 5 years. These data could provide a reference for brain function rehabilitation in children with illness or abnormal function. We acquired functional magnetic resonance images from 15 3-year-old children and 15 5-year-old children under natural sleep cond让ions. The participants were recruited from five kindergartens in the Nanshan District of Shenzhen City, China. The parents of the participants signed an informed consent form with the premise that they had been fully informed regarding the experimental protocol. We used masked independent component analysis and BrainNet Viewer software to explore the independent components of the brain and correlation connections between brain regions. We identified seven independent components in the two groups of children, including the executive control network, the dorsal attention network, the default mode network, the left frontoparietal network, the right frontoparietal network, the salience network, and the motor network. In the default mode network, the posterior cingulate cortex, medial frontal gyrus, and inferior parietal lobule were activated in both 3- and 5-year-old children, supporting the "three-brain region theory” of the default mode network. In the frontoparietal network, the frontal and parietal gyri were activated in the two groups of children, and functional connectivity was strengthened in 5-year-olds compared with 3-year-olds, although the nodes and network connections were not yet mature. The high-correlation network connections in the default mode networks and dorsal attention networks had been significantly strengthened in 5-year-olds vs. 3-year-olds. Further, the salience network in the 3-year-old children included an activated insula/inferior frontal gyrus-anterior cingulate cortex network circu让 and an activated thalamus-parahippocampal-posterior cingulate cortex-subcortical regions network circuit. By the age of 5 years, no des and high-correlation network connections (edges) were reduced in the salience network. Overall, activation of the dorsal attention network, default mode network, left frontoparietal network, and right frontoparietal network increased (the volume of activation increased, the signals strengthened, and the high-correlation connections increased and strengthened) in 5-year-olds compared with 3-year-olds, but activation in some brain nodes weakened or disappeared in the salience network, and the network connections (edges) were reduced. Between the ages of 3 and 5 years, we observed a tendency for function in some brain regions to be strengthened and for the generalization of activation to be reduced, indicating that specialization begins to develop at this time. The study protocol was approved by the local ethics committee of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences in China with approval No. SIAT-IRB- 131115-H0075 on November 15, 2013. 展开更多
关键词 nerve REGENERATION FUNCTIONAL MRI BRAIN network FUNCTIONAL connectivity RESTING-STATE ICA BRAIN development children RESTING-STATE networkS INFANT template standardized neural REGENERATION
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S-curve networks and an approximate method for estimating degree distributions of complex networks 被引量:2
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作者 郭进利 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期68-74,共7页
In the study of complex networks almost all theoretical models have the property of infinite growth, but the size of actual networks is finite. According to statistics from the China Internet IPv4 (Internet Protocol ... In the study of complex networks almost all theoretical models have the property of infinite growth, but the size of actual networks is finite. According to statistics from the China Internet IPv4 (Internet Protocol version 4) addresses, this paper proposes a forecasting model by using S curve (logistic curve). The growing trend of IPv4 addresses in China is forecasted. There are some reference values for optimizing the distribution of IPv4 address resource and the development of IPv6. Based on the laws of IPv4 growth, that is, the bulk growth and the finitely growing limit, it proposes a finite network model with a bulk growth. The model is said to be an S-curve network. Analysis demonstrates that the analytic method based on uniform distributions (i.e., Barabasi-Albert method) is not suitable for the network. It develops an approximate method to predict the growth dynamics of the individual nodes, and uses this to calculate analytically the degree distribution and the scaling exponents. The analytical result agrees with the simulation well, obeying an approximately power-law form. This method can overcome a shortcoming of Barabasi-Albert method commonly used in current network research. 展开更多
关键词 complex network scale-free network power-law distribution IPv4 standard logistic curve
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基于空-天-地一体化的电力现场新型应急通信系统研究及应用
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作者 潘海囤 张栋 +3 位作者 焦立彬 刘俊超 张华琳 吴嘉龙 《电力信息与通信技术》 2026年第2期87-91,共5页
近年来,极端灾害频发给电力保障救援带来巨大挑战,对电力部门应急保障能力提出了更高要求。文章针对“断路”、“断电”、“断网”复杂场景,采用多制式融合终端、音视频弱网可靠传输和多载波正交频分复用技术,设计开发了一套空-天-地一... 近年来,极端灾害频发给电力保障救援带来巨大挑战,对电力部门应急保障能力提出了更高要求。文章针对“断路”、“断电”、“断网”复杂场景,采用多制式融合终端、音视频弱网可靠传输和多载波正交频分复用技术,设计开发了一套空-天-地一体化电力现场新型应急通信系统。该系统已成功应用于河南电网、南方电网等公司,构建了空-天-地一体化、多制式融合、灵活组网的全天候电力应急指挥通信体系,为电力应急抢修和重要保电保障提供坚实的通信支撑。 展开更多
关键词 电力应急通信 空-天-地一体化 多制式融合 弱网可靠传输
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