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Coupled effect of climate change and human activities on the restoration/degradation of the Qinghai-Tibet Plateau grassland

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Journal of Geographical Sciences 2021年第9期31卷 1299-1327页

作者： YUAN Qin YUAN Quanzhi ren ping Institute of Geography and Resources Science Sichuan Normal UniversityChengdu 610101China Sustainable Development Research Center of Resources and Environment of Western Sichuan Sichuan Normal UniversityChengdu 610066China Key Laboratory of Land Resources Evaluation and Monitoring in Southwest Ministry of EducationSichuan Normal UniversityChengdu 610066China

Climate change(CC)and human activities(HA)are the main reasons for the restoration/degradation of the Qinghai-Tibet Plateau(QTP)*** related studies have been conducted thus far,but the impact mechanism of CC coupled with HA on QTP remains *** summarized the two main coupling factors in recent years(specifically,in the past five years)and obtained the following conclusions.(1)CC and HA have positive and negative effects on the QTP grassland *** primarily affects grassland ecology through temperature,humidification,and extreme climate,and HA mainly affects ecosystems through primary,secondary,and tertiary industries and restoration measures.(2)CC coupled with HA affects soil,plants,animals,and fungi/*** makes the snow line rise by increasing the temperature,which expands the zone for *** also restricts HA through hydrological changes,extreme climate,and outbreak of pikas and ***,measures are implemented through HA to control and adapt to ***,the grassland ecosystem is comprehensively influenced by CC and HA.(3)The grassland ecosystem dynamically adapts to the disturbance caused by CC and HA by changing its physiological characteristics,distribution range,diet structure,community structure,and physical ***,it responds to environmental changes through desertification,poisonous weeds,rodent outbreak,release of harmful gases,and other *** work can be used as a reference for the sustainable development of the QTP grassland.

关键词： Qinghai-Tibet Plateau geochemistry soil organic carbon net primary productivity pikas pests Cordyceps sinensis

Boosting multi-features with prior knowledge for mini unmanned helicopter landmark detection

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 256-261页

作者： Qin-yuan ren ping LI Bo HAN The State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

Without sufficient real training data,the data driven classification algorithms based on boosting method cannot solely be utilized to applications such as the mini unmanned helicopter landmark image *** this paper,we propose an approach which uses a boosting algorithm with the prior knowledge for the mini unmanned helicopter landmark image *** stage forward stagewise additive model of boosting is analyzed,and the approach how to combine it with the prior knowledge model is *** approach is then applied to landmark image detection,where the multi-features are boosted to solve a series of problems,such as rotation,noises affected,*** of real flight experiments demonstrate that for small training examples the boosted learning system using prior knowledge is dramatically better than the one driven by data only.

关键词： Boosting Prior knowledge model Landmark detection

基于OpenFOAM对某溢洪道挑流水动力特性的两相流数值研究

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水电能源科学 2024年第1期42卷 115-119页

作者：刘晗月任春平黄旭中太原理工大学水利科学与工程学院山西太原030024

挑流消能中水舌在空中段及跌落到下游水垫塘的过程中,均存在明显的气液两相流特性,为更加深入探明该过程中的水动力特性,需构建更加先进的气液两相流数值模型。运用CFD开源软件OpenFOAM构建两相流三维数值模型,通过挑流试验测得的水舌... 详细信息

挑流消能中水舌在空中段及跌落到下游水垫塘的过程中,均存在明显的气液两相流特性,为更加深入探明该过程中的水动力特性,需构建更加先进的气液两相流数值模型。运用CFD开源软件OpenFOAM构建两相流三维数值模型,通过挑流试验测得的水舌结果对该数值模型进行验证,结果表明数值模拟结果与试验结果吻合较好,同时通过数值研究发现κ-ωSST湍流模型优于κ-ε、κ-ω湍流模型。将κ-ωSST湍流模型得到的数值模拟结果与已有挑流射程经验公式进行比较,结果表明κ-ωSST湍流模型比经验公式计算结果更接近试验结果。最后,基于数值模拟结果分析射流作用下水垫塘的动水压力分布特征,发现塘底湍动能最大值位于距挑坎1.26L_(1)、1.23L_(2)、1.093L_(3)、1.001L_(4)处。最大塘底压强位于距挑坎约0.91L3处,此处也是整个计算域流速最低的流速滞点。研究结果可为挑流过程的相关研究提供参考。

关键词：挑流气液两相流 OpenFOAM 模型试验湍流模型

Dual-mode predictive control of a rotor suspension system

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Science China(Information Sciences) 2020年第1期63卷 178-189页

作者： Yue WU Gui-ping ren Hai-Tao ZHANG Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and Technology State Key Laboratory of Digital Manufacturing Equipments and Technology

Rotor active magnetic bearing(rotor-AMB) systems are frequently used to alleviate vibrations for various applications such as in national defense, manufacturing industries, IC production, and aerospace engineering. One obstacle to improve machining efficiency and quality is the open-loop instability of rotorAMB systems during the machining process. We built a closed-loop processing platform using a spindle rotor installed with AMBs and thereby developed a rotor-AMB suspension system embedded with a dual-mode predictive controller(DMPC). The performance of the system is thus substantially improved. In the proposed DMPC, both model-based prediction and receding horizon optimization are utilized to guarantee the closedloop stability of the rotor-AMB suspension systems with input constraints. Finally, the effectiveness and superiority of the proposed method are examined through substantial levitation experiments on a machining platform with installed AMBs.

关键词： dual-mode predictive control system identification optimization control model predictive control suspension control

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多功能海军导弹运输车技术研究

现代防御技术 2024年第1期52卷 111-115页

作者：汪晓军任平崔树林赵丽丽北京机械设备研究所北京100854 海装驻北京地区第二军事代表室北京100854

针对海军舰载导弹转运及装舰过程中,运输车功能单一、通用性差,且装舰操作流程繁琐、时间长的问题,提出一种多功能导弹运输车的技术方案,该方案以通用化和结构功能一体化为设计理念,对运输车的运输功能与辅助起竖功能进行一体化设计,在... 详细信息

针对海军舰载导弹转运及装舰过程中,运输车功能单一、通用性差,且装舰操作流程繁琐、时间长的问题,提出一种多功能导弹运输车的技术方案,该方案以通用化和结构功能一体化为设计理念,对运输车的运输功能与辅助起竖功能进行一体化设计,在满足海通各型导弹公路运输功能的前提下,集成导弹水平、垂直姿态转换的功能,突破筒弹在舰面装填方式的限制,解决筒弹装舰过程中吊装流程繁琐的问题,实现在运输车上直接起竖筒弹的功能,缩短筒弹装舰时间。该方案使得舰载导弹转运、装舰的流程得以简化,提升了装备的使用效能。

关键词：导弹运输装填通用起竖姿态转换多功能集成

融合文本图卷积神经网络与注意力机制的唐诗情感分析

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湖北民族大学学报（自然科学版） 2024年第2期42卷 205-211页

作者：蒋天奇方贤进任萍安徽理工大学计算机科学与工程学院安徽淮南232001

针对目前唐诗情感分析任务的语义提取不充分、数据集不完善的问题,构建了一个全新的唐诗情感分类数据集且进一步细化了情感极性,提出了一种融合文本图卷积神经网络与注意力机制(text-graph convolutional neural networks with attentio... 详细信息

针对目前唐诗情感分析任务的语义提取不充分、数据集不完善的问题,构建了一个全新的唐诗情感分类数据集且进一步细化了情感极性,提出了一种融合文本图卷积神经网络与注意力机制(text-graph convolutional neural networks with attention mechanism,AM-Text-GCN)的情感分类模型。模型首先结合双向长短期记忆网络(bi-directional long short-term memory,BiLSTM)和注意力机制捕捉唐诗中的上下文信息和诗句间的语义特征,然后利用融入依存句法分析的2层文本图卷积神经网络在图卷积操作中聚合唐诗全局特征,最终输出唐诗的情感极性。结果表明,所提出模型的S F1值达了79.83%,相较于文本图神经网络的S F1值提高了5.46%,有效地提高了唐诗情感分析的准确性。该研究对于探索诗词情感在历史变迁中的作用具有重要意义和广泛的应用前景。

关键词：情感分析唐诗文本图卷积神经网络注意力机制双向长短期记忆网络

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基于图卷积的神经网络硬件加速器设计

中国集成电路 2024年第1期33卷 24-29,50页

作者：常静涛王仁平福州大学物理与信息工程学院

目前很多的应用都需要用图数据来表示和处理,图数据是位于非欧几里得空间中的不规则数据,出于图数据处理的需求,图卷积神经网络(GCN)应运而生。GCN的主要处理步骤有:聚合,转换和激活。在本文中,我们采用一种异构模式对GCN的推理过程进... 详细信息

目前很多的应用都需要用图数据来表示和处理,图数据是位于非欧几里得空间中的不规则数据,出于图数据处理的需求,图卷积神经网络(GCN)应运而生。GCN的主要处理步骤有:聚合,转换和激活。在本文中,我们采用一种异构模式对GCN的推理过程进行加速。根据数据本身的特点,在转换阶段,加速器采用脉动阵列执行计算来改善数据流,在聚合阶段,将所要处理的负载分成两种类型,有助于改善聚合阶段计算过程中的负载不平衡现象,同时在一定程度上缩短计算时间。最后,通过在Xilinx Virtex UltraScale+VU37P HBM FPGA平台上进行性能评估,本工作相对于CPU和GPU分别实现了平均389.19×和6.73×的加速。

关键词：图卷积机器学习硬件加速

Researches on the Structure and Properties of Mullite Solid Solution Made from Industrial Waste

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Chinese Journal of Structural Chemistry 2006年第8期25卷 965-970页

作者： RUAN Yu-Zhong YU Yan WU ren-ping College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

The waste slag from aluminum profile factory and silicon fine powder from ferroalloy factory were utilized as the main raw materials to synthesize mullite solid solution Al4＋2xSi2-xO10-x/2, whose defect formation mechanism, crystalline phase composition, crystal cell parameters, microstructures and morphologies were characterized in detail by XRD and SEM. The results show that because of the ultrafine particle size of the materials, the content of mullite solid solution synthesized by this method is higher than that by regular method. Keywords： waste slag from aluminum factory, silicon fine powder, mullite, solid solution

关键词： waste slag from aluminum factory silicon fine powder mullite solid solution

Studies on the Structure and Properties of Multiphase Al_2O_3 Abrasion-resistant Ceramics

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Chinese Journal of Structural Chemistry 2006年第7期25卷 805-810页

作者： WU ren-ping YU Yan RUAN Yu-Zhong College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

The Al2O3 abrasion-resistant ceramics is successfully prepared by using waste aluminum sludge as the main raw material with the addition of a little clay, talc and barium carbonate. The crystal structure and microstructure of ceramic are characterized by means of XRD, SEM, etc., and the physical and mechanical properties are also tested. The results show that besides the phase of corundum, a little mullite, Mg-Al spinel and hyalophane phases also exist in the product. These phases are produced via reaction in-situ, which can inhibit the overgrowth of Al2O3 grain in grain boundary, and improve the integral property of the material.

关键词： Al2O3 ceramic crystal structure property in-situ synthesis