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From Website to Platform:The Nationalism Transformation of Chinese Young Netizens
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作者 Chaoyi Ding 《Sociology Study》 2026年第1期60-63,共4页
With the transformation from websites to Internet platforms, Chinese young netizens (born in 1990-2005) have become key subjects in the evolution of cyber-nationalism. Based on survey data, this study classifies their... With the transformation from websites to Internet platforms, Chinese young netizens (born in 1990-2005) have become key subjects in the evolution of cyber-nationalism. Based on survey data, this study classifies their nationalism into four types and explores its transformation alongside globalization cognition. The result shows that moderate nationalism is the mainstream. This has raised their attention to globalization, with greater focus on relations between China and developing countries, and nations along the Belt and Road Initiative. Their personal experiences and cultural exposure foster a more inclusive global vision, shaping the evolution of nationalism and global dialogue. 展开更多
关键词 Internet platform NATIONALISM young netizens social mentality GLOBALIZATION
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FAIR-DQL:Fairness-Aware Deep Q-Learning for Enhanced Resource Allocation and RIS Optimization in High-Altitude Platform Networks
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作者 Muhammad Ejaz Muhammad Asim +1 位作者 Mudasir Ahmad Wani Kashish Ara Shakil 《Computers, Materials & Continua》 2026年第3期758-779,共22页
The integration of High-Altitude Platform Stations(HAPS)with Reconfigurable Intelligent Surfaces(RIS)represents a critical advancement for next-generation wireless networks,offering unprecedented opportunities for ubi... The integration of High-Altitude Platform Stations(HAPS)with Reconfigurable Intelligent Surfaces(RIS)represents a critical advancement for next-generation wireless networks,offering unprecedented opportunities for ubiquitous connectivity.However,existing research reveals significant gaps in dynamic resource allocation,joint optimization,and equitable service provisioning under varying channel conditions,limiting practical deployment of these technologies.This paper addresses these challenges by proposing a novel Fairness-Aware Deep Q-Learning(FAIRDQL)framework for joint resource management and phase configuration in HAPS-RIS systems.Our methodology employs a comprehensive three-tier algorithmic architecture integrating adaptive power control,priority-based user scheduling,and dynamic learning mechanisms.The FAIR-DQL approach utilizes advanced reinforcement learning with experience replay and fairness-aware reward functions to balance competing objectives while adapting to dynamic environments.Key findings demonstrate substantial improvements:9.15 dB SINR gain,12.5 bps/Hz capacity,78%power efficiency,and 0.82 fairness index.The framework achieves rapid 40-episode convergence with consistent delay performance.These contributions establish new benchmarks for fairness-aware resource allocation in aerial communications,enabling practical HAPS-RIS deployments in rural connectivity,emergency communications,and urban networks. 展开更多
关键词 Wireless communication high-altitude platform station reconfigurable intelligent surfaces deep Q-learning
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Integrated Sharing Platform for Genetic Data of Rare and Precious Metal Materials
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作者 Lin Huang Ying Zhou Jingjing Yang 《Computers, Materials & Continua》 2025年第12期4587-4606,共20页
The construction of centralized and standardized material databases is essential to support both scientific innovation and industrial application.However,for rare and precious metal materials,existing data resources a... The construction of centralized and standardized material databases is essential to support both scientific innovation and industrial application.However,for rare and precious metal materials,existing data resources are often decentralized.This results in persistent issues such as data silos and fragmentation,which significantly hinder efficient data utilization and collaboration.In response to these challenges,this study investigates the development of an integrated platform for sharing genetic data of rare and precious metal materials.The research begins by analyzing current trends in material data platforms,both domestically and internationally.These insights help inform the architectural design.The core of the platform consists of several key modules.Data resource integration is designed to aggregate and harmonize heterogeneous data from diverse sources.A structured data management system supports efficient storage and retrieval.A computational environment enables data analysis and modeling.A trusted sharing mechanism ensures security and access control.By integrating these functionalities,the platform aims to provide a unified ecosystem.This system facilitates open yet secure data exchange,promotes reproducibility,and enhances research efficiency.Finally,the article summarizes the initial implementation of the platform.It discusses its potential limitations and outlines future directions for development,including the integration of artificial intelligence tools and the expansion of data coverage. 展开更多
关键词 Material gene engineering DATABASE platform construction blockchain
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Enterprise Digital Planning and Architecture Based on the Industrial Internet Platform
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作者 Li Wang Xiong Li +2 位作者 Juan Zhang Ming Luo Mengwei Liu 《Journal of Electronic Research and Application》 2025年第3期137-143,共7页
Under the current background of an information society,the digital transformation of enterprises has become a necessary means to enhance the competitiveness of enterprises.This article is based on the industrial Inter... Under the current background of an information society,the digital transformation of enterprises has become a necessary means to enhance the competitiveness of enterprises.This article is based on the industrial Internet platform,the digital planning and architecture of enterprises research.First,we analyze the current challenges of digital transformation and the development opportunities brought by the industrial Internet.Then,we propose a digital planning method based on the industrial Internet platform,which takes the full connectivity of people,machine and things and intelligent decision making as the core,takes data collection,processing,analysis and application as the main line,and finally forms the top-level design of the digital transformation of enterprises.At the same time,we also built an industrial Internet platform architecture model,including the previous end perception layer,network transmission layer,platform service layer,and application innovation layer for four levels,to support enterprises in innovative applications and decision support under the industrial Internet environment.Research shows that this kind of enterprise digital planning and architecture based on an industrial Internet platform can effectively promote enterprises to achieve business model innovation,system innovation,and strengthen the flexibility and agility of enterprises to respond to market changes.The results of this research not only have important theoretical and practical significance for guiding enterprises to carry out digital planning and build an industrial Internet platform,but also provide useful reference for relevant policy formulation. 展开更多
关键词 Industrial internet platform Enterprise digital planning Architecture model Innovative application AGILITY
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Timeshare surface-enhanced Raman scattering platform with sensitive and quantitative mode
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作者 Qianqian Ding Xueyan Chen +4 位作者 Yunlu Jia Hong Liu Xiaochen Zhang Ningtao Cheng Shikuan Yang 《Opto-Electronic Advances》 2026年第1期65-74,共10页
The sensitivity and quantification capability of surface-enhanced Raman scattering(SERS)substrates are mutually exclusive,because the ultrasensitive SERS sites(hottest spots)necessary for the sensitivity will signific... The sensitivity and quantification capability of surface-enhanced Raman scattering(SERS)substrates are mutually exclusive,because the ultrasensitive SERS sites(hottest spots)necessary for the sensitivity will significantly magnify the SERS signals of the analyte molecules and thus each of these molecules will be miscounted to be hundreds during the quantification process.We demonstrate a concept to circumvent the above contradiction by engineering a timeshare SERS platform capable of working at the quantitative or the sensitive mode on demand.The timeshare SERS platform was constructed by transferring a monolayer gold nanosphere film onto elastic substrates(e.g.,hydrogel).The volume change of the hydrogel could adjust the inter-nanosphere distance,dynamically controlling the formation or extinction of the SERS hottest spots on the same SERS substrate without influencing the spatial distribution of the analyte molecules.The timeshare SERS platform without the SERS hottest spots showed strong quantification capability,while when equipped with a substantial number of the SERS hottest spots exhibited ultrahigh sensitivity.We demonstrated quantitative and ultrasensitive detection of various analyte molecules using the quantitative and the sensitive mode of the timeshare SERS platform,respectively.We opened an avenue towards designing SERS substrates with both high sensitivity and strong quantification capability. 展开更多
关键词 timeshare SERS platform sensing quantification HYDROGEL gold nanosphere
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Carbon dots-embedded hydrogel ratiometric fluorescent platform for portable determination of doxorubicin in clinical samples
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作者 Xin Liu Haoran Zhu +6 位作者 Yi Wang Haili Zhang Yujie Li Hongcheng Gao Yi Han Dejin Wang Yunsheng Xia 《Chinese Chemical Letters》 2026年第2期465-470,共6页
Portable ratiometric fluorescent platforms have emerged as promising tools for multifarious detection,yet remain unexplored for point-of-care monitoring doxorubicin(DOX),one of clinically antineoplastic drugs.To this ... Portable ratiometric fluorescent platforms have emerged as promising tools for multifarious detection,yet remain unexplored for point-of-care monitoring doxorubicin(DOX),one of clinically antineoplastic drugs.To this end,we herein develop a portable self-calibrating platform namely carbon dots(C-dots)-embedded hydrogel sensors with a smartphone-assisted high-throughput imaging device,for DOX sensing.The prepared green-emitting(λ_(em)=508 nm)and negatively-charged C-dots(−11.40±1.21 mV),which have sufficient spectral overlap with the absorption band of DOX(∼500 nm),can strongly bind with positively-charged DOX molecules by electrostatic attraction effects.As a result,DOX molecules are selectively and rapid(20 s)determined with a detection limit of 10.26 nmol/L via Förster resonance energy transfer processes,demonstrating a remarkably chromatic shift from green to red.Further integrated with a 3D-printed smartphone-assisted device,the platform enabled high-throughput quantification,achieving recoveries of 96.40%-101.85%in human urine/serum(RSDs<2.94%,n=3).Notably,the dual linear detection ranges of the platform align with the reported clinical DOX concentrations in urine and plasma(0-4 h post-administration),validating their capability for direct quantification of DOX in clinical samples without special pre-treatment processes.By virtue of attractive analytical performances and robust feasibility,this platform bridges laboratory precision and point-of-care testing needs,offering promising potential for personalized chemotherapy and multiplexed analyte screening. 展开更多
关键词 Portable platform Carbon dots DOXORUBICIN Point-of-care monitoring Clinical samples
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Phytoremediation of cultural eutrophication:A floating-bed platform plant-based approach for freshwater ecological restoration in Qiandao Lake,an oligo-mesotrophic reservoir
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作者 Xiaolong Huang Kang Liu +5 位作者 Lili Xiong Biao Long Hai Xu Zhaoshi Wu Baohua Guan Kuanyi Li 《Ecological Frontiers》 2026年第1期343-350,共8页
Cultural eutrophication,driven primarily by anthropogenic activities,poses a severe threat to freshwater biodiversity.Aimed to evaluate how nutrient elements affect the phytoremediation potential of floating-bed plant... Cultural eutrophication,driven primarily by anthropogenic activities,poses a severe threat to freshwater biodiversity.Aimed to evaluate how nutrient elements affect the phytoremediation potential of floating-bed plants and to assessed select optimal species for ecological restoration.We investigated the functional traits of three floating-bed plants—edible Oenanthe javanica,Ipomoea aquatica,and ornamental Myriophyllum aquaticum—in Qiandaohu Lake,an oligo-mesotrophic reservoir in China.A mesocosm experiment was conducted using different eutrophic nitrogen(N)and phosphorus(P)concentrations.Plant functional traits[shoot,root,and total biomass,relative growth rate(RGR),and maximum quantum yield of photosystemⅡ(F_(v)/F_(m))]and plant net N and P purification efficiency(μ)were measured.The results revealed that plant species significantly influenced all the traits,with P exerting a stronger effect than N;thus,P was identified as a critical limiting factor for growth and remediation performance,underscoring its role in cultural eutrophication.Specifically,M.aquaticum exhibited optimal eutrophication purification efficiency at high N and P concentrations.However,as an introduced non-invasive plant,M.aquaticum should be used cautiously for phytoremediation.This study highlights the application of floating-bed platforms in oligo-mesotrophic reservoirs,bridging ecological restoration with socioeconomic value. 展开更多
关键词 Floating-bed platform Functional traits Nutrient purification efficiency Non-native species Species-specific responses
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Research on Operation Strategies of Trade Publishing Knowledge Service Platform Based on the SICAS Model:A Case Study of CITIC Academy
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作者 WANG Jun ZHOU Xiaoyi 《Cultural and Religious Studies》 2026年第1期13-21,共9页
Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.... Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.To address this issue,this paper employs a combined approach of theoretical analysis and case study,introducing the SICAS(Sense-Interest-Connection-Action-Share)user consumption behavior analysis model and selecting“CITIC Academy”as the case study subject.It systematically examines and summarizes the platform’s operational practices and specific strategies,aiming to offer strategic insights and practical references for the operational improvement and sustainable,high-quality development of trade publishing knowledge service platforms. 展开更多
关键词 trade publishing knowledge service platform SICAS model operation strategy CITIC Academy
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Research on the Construction and Application of an Integrated Teaching Platform Combining Virtual Simulation and High-End Simulators in Practical Obstetrics and Gynecology Teaching
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作者 Shuo Feng Ao Li +2 位作者 Chao Wang Hui Wang Yingui Sun 《Journal of Clinical and Nursing Research》 2026年第2期263-269,共7页
Objective:To analyze the effectiveness of an integrated teaching platform combining virtual reality(VR)technology and high-end simulators in practical obstetrics and gynecology teaching.Methods:A total of 39 interns w... Objective:To analyze the effectiveness of an integrated teaching platform combining virtual reality(VR)technology and high-end simulators in practical obstetrics and gynecology teaching.Methods:A total of 39 interns who underwent obstetrics and gynecology internships from March 2023 to March 2024 were included in the reference group and received conventional practical teaching methods.Another 39 interns who underwent internships from April 2024 to April 2025 were included in the observation group and received the integrated teaching platform combining VR and high-end simulators.The teaching effects of the two groups were compared.Results:The observation group achieved higher assessment scores than the reference group,with higher scores in self-directed learning ability and clinical thinking ability after teaching,as well as higher teaching satisfaction(p<0.05).Conclusion:The integrated teaching platform combining VR and high-end simulators can improve the assessment scores of obstetrics and gynecology interns,cultivate their self-directed learning ability and clinical thinking ability,and achieve high teaching satisfaction. 展开更多
关键词 Virtual reality High-end simulator Integrated teaching platform Obstetrics and gynecology Practical teaching
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Erratum to"Amine-reactive Polymer Platform for Engineering Surface Modification of Next-generation Sequencing Chips"
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作者 Wei Tian Xin-Yuan Wang +4 位作者 Die-Wen Feng Xiang-Qian Li Yue-Kang Jin Hui Li Hao Liu 《Chinese Journal of Polymer Science》 2026年第1期314-314,I0019,共2页
We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by&quo... We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China".We apologized for the inconvenience caused by this error. 展开更多
关键词 erratum surface modification affiliation next generation sequencing chips reactive polymer platform advanced fiber materialscenter
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Eight Core Trends:From Trade Show Floors to Ecosystem Platforms
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作者 Lan Xin 《China's Foreign Trade》 2026年第1期11-14,共4页
At a critical juncture of global industrial transformation and economic recovery,the 2026 China Expo Forum for International Cooperation(CEFCO)recently concluded in Wuhan.Dubbed the“Davos of the exhibition industry”... At a critical juncture of global industrial transformation and economic recovery,the 2026 China Expo Forum for International Cooperation(CEFCO)recently concluded in Wuhan.Dubbed the“Davos of the exhibition industry”,the forum,attracted more than 600 exhibition professionals from over 20 countries and regions. 展开更多
关键词 trade show floors industrial transformation ecosystem platforms wuhan China expo forum international cooperation davos exhibition industry economic recovery cefco
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基于NS-3的SD-MANET仿真平台设计与实现
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作者 袁洋 杨力 何流 《兵工学报》 北大核心 2026年第3期158-179,共22页
软件定义自组网(Software Defined Mobile Ad Hoc Network,SD-MANET)融合了软件定义网络(Software Defined Network,SDN)集中控制优势和移动自组网(Mobile Ad Hoc Network,MANET)的动态组网优势,但Mininet等现有仿真平台在动态拓扑与扩... 软件定义自组网(Software Defined Mobile Ad Hoc Network,SD-MANET)融合了软件定义网络(Software Defined Network,SDN)集中控制优势和移动自组网(Mobile Ad Hoc Network,MANET)的动态组网优势,但Mininet等现有仿真平台在动态拓扑与扩展性等方面存在显著局限,严重制约了其关键算法的研究。针对这一问题,提出基于网络模拟器-3(Network Simulator-3,NS-3)的仿真平台NS3-SDMANET,具体工作包括:基于NS-3框架实现了SD-MANET网络层关键特性的仿真;基于远程过程调用对平台功能进行封装,并提供可编程接口。战术网的测试案例表明:NS3-SDMANET在SD-MANET网络层关键特性仿真方面表现优异,能够有效支撑SD-MANET网络层算法的高效验证与性能评估,为相关研究提供了高扩展性的基础仿真环境。 展开更多
关键词 软件定义网络 移动自组网 网络模拟器-3 可编程网络仿真平台
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一种结合ZigBee与OneNET云平台的多终端室内无线消防数据采集与预警系统
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作者 田军南 陈樟柯 +1 位作者 李伟 蒋吉慧 《机械设计与制造》 北大核心 2026年第4期264-271,共8页
针对当前火灾隐患不易发觉、消防检查数据采集难、消防检查工作量大等问题,设计了一种结合ZigBee与OneNET云平台的多终端室内无线消防数据采集与预警系统。该系统以STM32为核心主控制器,硬件部分包括ZigBee模块、GSM模块、GPS定位模块... 针对当前火灾隐患不易发觉、消防检查数据采集难、消防检查工作量大等问题,设计了一种结合ZigBee与OneNET云平台的多终端室内无线消防数据采集与预警系统。该系统以STM32为核心主控制器,硬件部分包括ZigBee模块、GSM模块、GPS定位模块、显示模块、WiFi模块、电动水阀控制模块、报警模块以及温湿度等环境数据采集传感器。软件部分利用ZigBee模块通信驱动程序、数据存储与分析模块以及OneNET云平台等实现所设计的功能。系统通过传感器采集数据,并借助卡尔曼-指数平滑滤波进行数据预处理,再传输至主控制器,利用基于阈值的火灾探测算法进行判断,并实时将监测数据上传至OneNET云平台进行数据存储、分析和预警。测试结果表明,该设计方案稳定可靠,实现了消防数据采集和预警的智能化、简便化及科学化,能够有效保障消防安全和人员的生命安全。 展开更多
关键词 ZIGBEE Onenet云平台 数据预处理 火灾预警 多终端
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基于NetLogo平台的大病保险多主体博弈仿真模型构建研究
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作者 赖勇强 苗雯青 +4 位作者 戈倩倩 王欣雨 曲芳琪 陈瑞 李叶 《中国卫生经济》 北大核心 2026年第2期32-37,50,共7页
目的:旨在探索性地引入基于主体的建模仿真方法,构建科学的模型架构,为优化城乡居民大病保险政策提供有力支撑。方法:以某省的数据为变量参数,依托NetLogo仿真建模平台进行虚拟世界的构建与模拟运行,对基金筹集、基金使用和基金结算3个... 目的:旨在探索性地引入基于主体的建模仿真方法,构建科学的模型架构,为优化城乡居民大病保险政策提供有力支撑。方法:以某省的数据为变量参数,依托NetLogo仿真建模平台进行虚拟世界的构建与模拟运行,对基金筹集、基金使用和基金结算3个主要方向展开仿真模拟。结果:提升职工基本医保基金池共济比例至2%可使大病保险结余率转正。分段报销大幅降低患者自付费用,平均减负约0.0629万元,降幅12.55%。商业保险公司3%盈亏率叠加50%额外风险分担比例时,双方亏损差值仅0.1807万元。结论:研究结合样本省实际情况进行方案设计并完成仿真模拟,最终形成了对筹资渠道拓展、报销方式调整、风险分担机制的瞄准与利益主体博弈均衡点的锁定与预测,为大病保险政策优化提供了有力支撑。 展开更多
关键词 大病保险 多主体博弈 医保基金 仿真模拟 netLogo平台
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Design and Implementation of an Open Network Security Management Platform 被引量:2
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作者 曹元大 王勇 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期316-320,共5页
In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasib... In order to manage all kinds of network security devices and software systems efficiently, and make them collaborate with each other, the model for an open network security management platform is presented. The feasibility and key implementing technology of the model are expatiated. A prototype system is implemented to validate it. 展开更多
关键词 network security management open platform XML RPC SNMP
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Dendritic Growth Pattern and Dendritic Network Distortion in the Platform of a Ni-based Superalloy 被引量:6
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作者 Xiaoli Zhang Yizhou Zhou +2 位作者 Yanyun Han Tao Jin Xiaofeng Sun 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2014年第3期223-228,共6页
The pattern of dendritic growth and distortion of dendritic network in the platform have been investigated by one mold casting with different platform length during directional solidification. As the platform length e... The pattern of dendritic growth and distortion of dendritic network in the platform have been investigated by one mold casting with different platform length during directional solidification. As the platform length elongates, the symmetry of dendritic growth along left and right edges gradually worsens in platform base. While the platform length reaches 14 mm, the distortion of dendritic network is first observed in outward platform. It is found that the distortion of dendritic network along platform inside is more serious than that along platform edges. Both [001] deviation and accumulated misorientation along platform inside, up to 9~ and 16.3~, respectively, are far greeter than those along left-outward-right edges. The deformation of dendritic network in a platform may be caused by the asymmetry of the solidification front at the mush zone. 展开更多
关键词 SUPERALLOY Directional solidification Dendritic growth Grain orientation platform
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Active Vibration Isolation of Micro-Manufacturing Platform Based on Neural Network 被引量:4
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作者 ZHANG Chun-liang, MEI De-qing, CHEN Zi-chen (Institute of Production Engineering, Zhejiang University, Hangzhou 310027, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期67-68,共2页
The micromation and precision of the Micro-Electromechanical System demand that its manufacturing, measuring and assembling must work in a micro-manufacturing platform with good ability to isolate vibrations. This pap... The micromation and precision of the Micro-Electromechanical System demand that its manufacturing, measuring and assembling must work in a micro-manufacturing platform with good ability to isolate vibrations. This paper develops a vibration isolation system of micro-manufacturing platform. The brains of many kinds of birds can isolate vibrations well, such as woodpecker’s brain. When a woodpecker pecks the wood at the speed as 1.6 times as the velocity of sound, its brain will tolerate the wallop 1 500 times of the weight of itself without any damage. The isolation mechanics and organic texture of woodpecker’s brain that has good isolation characteristics were studied. A structure model of vibration isolation system for the micro-manufacturing platform is established based on the bionics of the bird’s brain vibration isolation mechanism. In order to isolate effectively the high frequency vibrations from the ground, a rubber layer is used to isolate vibrations passively between the micro-manufacturing platform’s pedestal and the ground. This layer corresponds to the cartilage and muscles in the outer meninges of the bird’s brain. The active vibration isolation technique is adopted to isolate vibrations between the micro-manufacturing platform and the pedestal. Air springs are used as elastic components, which correspond to the interspaces between the outer meninges and the encephala of the bird’s brain. Actuators are made of giant magnetostrictive material, and it corresponds to the nerves and neural muscles linking the meninges and the encephala. The actuators and air springs are arranged vertically in parallel to make use of the giant magnetostrictive actuators effectively. The air springs support almost all weight of the micro-manufacturing platform and the giant magnetostrictive actuators support almost no weight. In order to realize high performance to isolate complex micro-vibration, the control method using a three-layer neural network is presented. This vibration control system takes into account the floor disturbance and the direct disturbance acting on the micro-manufacturing platform. The absolute acceleration of the micro-manufacturing platform is used as the performance index of vibration control. The performance of the control system is tested by numerical simulation. Simulation results show that the active vibration isolation system has good isolation performance against the floor disturbance and the direct disturbance acting on the micro-manufacturing platform in all the frequency range. 展开更多
关键词 micro-manufacturing platform active vibration isolation bionic mechanics neural network
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Experiment Verification of Damage Detection for Offshore Platforms by Neural Networks 被引量:3
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作者 刁延松 李华军 +1 位作者 石湘 王树青 《China Ocean Engineering》 SCIE EI 2006年第3期351-360,共10页
In the present work, damage detection for offshore platforms is divided into three steps. Firstly, the located direction of the damaged member is detemfined by the pmbabilistic neural network with input of the change ... In the present work, damage detection for offshore platforms is divided into three steps. Firstly, the located direction of the damaged member is detemfined by the pmbabilistic neural network with input of the change rate of normalized medal frequency. Secondly, the profile and layer of the damaged member is also determined by the pmbabilistic neural network with input of the normalized damage-signal index. Finally, the damage extent is determined by the back propagation neural networks with input of the squared change rate of modal frequency. So the size of the network and the training time can be reduced greatly. All these networks are trained with simulated data obtained from the finite element model of an experiment model. Then these trained neural networks are examined with data obtained from impulse tests on the experiment model. The experiment results show that the trained neural networks are able to detect the damaged member with reasonable accuracy. 展开更多
关键词 damage detection offshore platform probabilistic neural networks back-propagation neural networks
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Neural Network-Based Active Control for Offshore Platforms 被引量:2
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作者 周亚军 赵德有 《海洋工程:英文版》 2003年第3期461-468,共8页
A new active control scheme, based on neural network, for the suppression of oscillation in multiple-degree-of-freedom (MDOF) offshore platforms, is studied in this paper. With the main advantages of neural network, i... A new active control scheme, based on neural network, for the suppression of oscillation in multiple-degree-of-freedom (MDOF) offshore platforms, is studied in this paper. With the main advantages of neural network, i.e. the inherent robustness, fault tolerance, and generalized capability of its parallel massive interconnection structure, the active structural control of offshore platforms under random waves is accomplished by use of the BP neural network model. The neural network is trained offline with the data generated from numerical analysis, and it simulates the process of Classical Linear Quadratic Regular Control for the platform under random waves. After the learning phase, the trained network has learned about the nonlinear dynamic behavior of the active control system, and is capable of predicting the active control forces of the next time steps. The results obtained show that the active control is feasible and effective, and it finally overcomes time delay owing to the robustness, fault tolerance, and generalized capability of artificial neural network. 展开更多
关键词 active control offshore platform neural network time delay VIBRATION
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Origin of Phosphorite Nodules of Lebedinsky Iron Deposit in Kursk Magnetic Anomaly (KMA) of the Russian Platform 被引量:2
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作者 Tourba Kamaye Phillip Romanovitch 《Journal of China University of Geosciences》 SCIE CSCD 2005年第2期170-177,182,共9页
Phosphorite has become increasingly important as the raw material for phosphatic fertilizer. Phosphorite nodules are widespread in the Kursk complex deposit (Russian platform). Genesis of these nodules has long been a... Phosphorite has become increasingly important as the raw material for phosphatic fertilizer. Phosphorite nodules are widespread in the Kursk complex deposit (Russian platform). Genesis of these nodules has long been a matter of debate, and this has hampered understanding of the mechanism and controls in the formation of the nodules. In this paper, we report the petrographical, mineralogical, and geochemical data of the Lebedinsky phosphorite nodules. Petrographic study reveals complex phosphatic cement resulting in the replacement of apatite minerals around quartz grains. The main mineral composition consists of quartz, phosphate minerals (apatite, francolite mainly), feldspar, iron hydroxides and carbonate minerals. These results, when combined with available data, are used to address the origin of the phosphorite nodules. The nodules are characterized by the universal presence of biogenic and chemical signatures which is phosphorus crown around crystal grains. The structure of the nodules is massive. Their texture is depicted by basaltic cement and concretion, which consists mainly of apatite and its varieties, with general formula: Ca_10 (PO_4, CO_3) 6(F,OH,Cl). Variation of mineralogy appears dependent on geological setting. Microscopic observations of biogenic fossils in Lebedinsky phosphorite favor a chemical and biogenic origin of phosphorites. Weathering has been suggested to be capable of liberating as much as 20 %-35 % P_2O_5 from sedimentary rocks. Previous investigations demonstrate that weathering of the Proterozoic substratum was the main cause in the formation of Fe, Mo, Mn, Pb, Zn, and P in the Russian platform. We therefore suggest that both weathering and biochemical processes have been positive in the formation of the Lebedinsky phosporite nodules. However, whether continental weathering or oceanic bio-chemical processes are more relevant in the phosphorite accumulation remains undetermined. 展开更多
关键词 nodular phosphorite Kursk magnetic anomaly Russian platform WEATHERING bio-chemical process
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