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Self-improvement of Teachers of Foreign Languages
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作者 Zhang Bingke (English Dept. Yan’an College of Education, Shaanxi 716000) 《延安教育学院学报》 2002年第3期31-33,共3页
The author points out that the foreign language teacher’s role as a best organizer in students’ study of foreign languages requires that teachers of foreign languages should have the good language teaching character... The author points out that the foreign language teacher’s role as a best organizer in students’ study of foreign languages requires that teachers of foreign languages should have the good language teaching characteristics mentioned in this essay. At the same time, the ways for foreign language teachers to realize self improvement are introduced with some necessary examples. 展开更多
关键词 中学 英语教师 自我修养 教学方法
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Improvement in the calculation of anti-Stokes energy transfer and experimental justification based on Er_(0.01)Yb_xY_(1 0.01 x)VO_4 crystal
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作者 陈晓波 卢建 +5 位作者 张蕴芝 徐小灵 冯宝华 王策 Gregory J. Salamo 杨国建 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期604-611,共8页
The improvement on the calculation of anti-Stokes energy transfer rate is studied in the present work. The additional proportion coefficient between Stokes and anti-Stokes light intensities of quantum Raman scattering... The improvement on the calculation of anti-Stokes energy transfer rate is studied in the present work. The additional proportion coefficient between Stokes and anti-Stokes light intensities of quantum Raman scattering theory as compared with the classical Raman theory is introduced to successfully describe the anti-Stokes energy transfer. The theoretical formula for the improvement on the calculation of anti-Stokes energy transfer rate is derived for the first time in this study. The correctness of introducing coefficient exp{△E/kT} from well-known Raman scatter theory is demonstrated also. Moreover, the experimental lifetime measurement in Er0.01YbxY1-0.01-xVO4 crystal is performed to justify the validity of our important improvement in the original phonon-assisted energy transfer theory for the first time. 展开更多
关键词 improvement of anti-Stokes energy transfer Raman scattering quantum and classical theory Er0.01YbxY1-0.01-xVO4 crystal
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基于MDS和改进SSA-SVM的高速铁路道岔故障诊断方法研究
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作者 王彦快 米根锁 +2 位作者 孔得盛 杨建刚 张玉 《铁道学报》 EI CAS CSCD 北大核心 2024年第1期81-90,共10页
针对高速铁路道岔设备故障频繁,现场维修工作量大等问题,提出基于多维尺度缩放法(MDS)和改进麻雀搜索算法(SSA)优化支持向量机(SVM)的高速铁路道岔故障诊断模型。首先以ZDJ9道岔转换功率曲线为研究对象,总结现场典型道岔故障类型及故障... 针对高速铁路道岔设备故障频繁,现场维修工作量大等问题,提出基于多维尺度缩放法(MDS)和改进麻雀搜索算法(SSA)优化支持向量机(SVM)的高速铁路道岔故障诊断模型。首先以ZDJ9道岔转换功率曲线为研究对象,总结现场典型道岔故障类型及故障原因,分别提取道岔功率曲线的时域、频域特征指标以及小波包能量熵,组成特征指标向量;其次采用MDS方法进行多维特征指标的降维优化,建立道岔故障特征指标样本数据库;最后利用改进Circle混沌映射初始化种群,并通过自适应t分布增强麻雀种群的多样性,再以改进SSA算法优化SVM模型中的惩罚因子和核函数方差2个关键参数,构建改进SSA-SVM的道岔故障诊断模型。故障诊断结果表明,本模型的故障诊断正确率高达96.25%,诊断效果优于其他方法,可以为道岔设备的故障维修提供理论依据。 展开更多
关键词 高速铁路道岔 故障诊断 改进麻雀搜索算法-支持向量机 Circle混沌映射 自适应t分布 小波包能量熵 多维尺度缩放法
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非最小相位的单电感双输出Buck-Boost变换器的复合控制方法
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作者 皇金锋 李啸天 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第6期1266-1274,1314,共10页
单电感双输出Buck-Boost (SIDO Buck-Boost)变换器在电感电流连续模式(CCM)下工作存在交叉影响以及非最小相位特性的问题.为了解决上述问题,提出基于储能函数的扩张状态观测器(ESO)的改进非奇异快速终端滑模(NFTSM)和自抗扰控制(ADRC)... 单电感双输出Buck-Boost (SIDO Buck-Boost)变换器在电感电流连续模式(CCM)下工作存在交叉影响以及非最小相位特性的问题.为了解决上述问题,提出基于储能函数的扩张状态观测器(ESO)的改进非奇异快速终端滑模(NFTSM)和自抗扰控制(ADRC)相结合的控制策略.设计主路控制器,对系统的传递函数进行拟合得到ADRC范式,利用该范式对主路进行解耦控制.设计支路控制器,采用改进型ESO对储能函数进行观测,并将观测值反馈补偿到非奇异快速终端滑模控制律中,达到支路解耦的效果.为了抑制滑模控制的抖振问题,对趋近律进行改进.利用Lyapunov理论证明系统稳定性.基于硬件在环(HIL)实验平台进行实验验证.结果表明,所提控制策略与PI控制策略以及基于ESO的滑模控制策略相比,在超调量和响应时间上具有较好的效果. 展开更多
关键词 单电感双输出 BUCK-BOOST变换器 非奇异快速终端滑模控制 自抗扰控制 改进滑模趋近律
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A new method of quality improvement for quadrilateral mesh based on small polygon reconnection 被引量:2
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作者 Jian-Fei Liu Shu-Li Sun Yong-Qiang Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期140-145,共6页
In this paper, a new method of topological cleanup for quadrilateral mesh is presented. The method first selects a patch of mesh around an irregular node. It then seeks the best connection of the selected patch accord... In this paper, a new method of topological cleanup for quadrilateral mesh is presented. The method first selects a patch of mesh around an irregular node. It then seeks the best connection of the selected patch according to its irregular valence using a new topological operation: small polygon reconnection (SPR). By replacing the original patch with an optimal one that has less irregular valence, mesh quality can be improved. Three applications based on the proposed approach are enumerated: (1) improving the quality of a quadrilateral mesh, (2) converting a triangular mesh to a quadrilateral one, and (3) adapting a triangle generator to a quadrilateral one. The presented method is highly effective in all three applications. 展开更多
关键词 Mesh improvement - Topological clean-up Quadrilateral mesh Small polygon reconnection
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OPTIMIZATION ON ANTENNA PATTERN OF SPACEBORNE SAR WITH IMPROVED NSGA-Ⅱ 被引量:2
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作者 Xiao Jiang Wang Xiaoqing +1 位作者 Zhu Minhui Xiao Liu 《Journal of Electronics(China)》 2009年第4期443-447,共5页
Optimization of antenna array pattern used in a spaceborne Synthetic Aperture Radar (SAR) system is considered in this study. A robust evolutionary algorithm, Non-dominated Sorting Genetic Algorithms (the improved NS... Optimization of antenna array pattern used in a spaceborne Synthetic Aperture Radar (SAR) system is considered in this study. A robust evolutionary algorithm, Non-dominated Sorting Genetic Algorithms (the improved NSGA-Ⅱ), is applied on a spaceborne SAR antenna pattern design. The system consists of two objective functions with two constraints. Pareto fronts are generated as a result of multi-objective optimization. After being validated by a test problem ZDT4, the algorithms are used to synthesize spaceborne SAR antenna radiation pattern. The good results with low Ambi- guity-to-Signal Ratio (ASR) and high directivity are obtained in the paper. 展开更多
关键词 Synthetic Aperture Radar (SAR) Radiation pattern improved Non-dominated Sorting Genetic Algorithms (NSGA)- Ambiguity-to-Signal Ratio (ASR)
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Self-expandable metal stents in patients with postoperative delayed gastric emptying after distal gastrectomy 被引量:3
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作者 Seung Han Kim Bora Keum +8 位作者 Hyuk Soon Choi Eun Sun Kim Yeon Seok Seo Yoon Tae Jeen Hong Sik Lee Hoon Jai Chun Soon Ho Um Chang Duck Kim Sungsoo Park 《World Journal of Gastroenterology》 SCIE CAS 2018年第40期4578-4585,共8页
AIM To investigate the efficacy and safety of endoscopic stent insertion in patients with delayed gastric emptying after gastrectomy.METHODS In this study, we prospectively collected data from patients who underwent s... AIM To investigate the efficacy and safety of endoscopic stent insertion in patients with delayed gastric emptying after gastrectomy.METHODS In this study, we prospectively collected data from patients who underwent stent placement for delayed gastric emptying(DGE) after distal gastrectomy between June 2010 and April 2017, at a tertiary referral academic center. Clinical improvement, complications, and consequences after stent insertion were analyzed.RESULTS Technical success was achieved in all patients(100%). Early symptom improvement was observed in 15 of 20 patients(75%) and clinical success was achieved in all patients. Mean follow-up period was 1178.3 ± 844.1 d and median stent maintenance period was 51 d(range 6-2114 d). During the follow-up period, inserted stents were passed spontaneously per rectum without any complications in 14 of 20 patients(70%). Symptom improvement was maintained after stent placement without the requirement of any additional intervention in 19 of 20 patients(95%).CONCLUSION Endoscopic stent placement provides prompt relief of obstructive symptoms. Thus, it can be considered an effective and safe salvage technique for post-operative DGE. 展开更多
关键词 self-expandable metal stent Delayed gastric EMPTYING GASTRECTOMY SALVAGE technique SYMPTOM improvement
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Dynamic Stress Analysis of the Leg Joints of Self-Elevating Platform 被引量:1
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作者 黄曌宇 唐文勇 +1 位作者 汪怡 王文涛 《China Ocean Engineering》 SCIE EI 2011年第2期319-326,共8页
Since a self-elevating platform often works in water for a long time, the lattice leg is largely influenced by wave and current. The amplitude of leg joint stresses is a very important factor for the fatigue life of t... Since a self-elevating platform often works in water for a long time, the lattice leg is largely influenced by wave and current. The amplitude of leg joint stresses is a very important factor for the fatigue life of the platform. However, there are not many researches having been done on the mechanism and dynamic stress analysis of these leg joints. This paper focuses on the dynamic stress analysis and suppression methods of the leg joints of self-elevating platforms. Firstly, the dynamic stresses of the lattice leg joints are analyzed for a self-elevating platform by use of the 5th-order Stokes wave theory. Secondly, the axial and bending stresses are studied due to their large contributions to total stresses. And then, different joint types are considered and the leg-hull interface stiffness is analyzed for the improvement of the joint dynamic stress amplitude. Finally, some useful conclusions are drawn for the optimization design of the self-elevating platform. 展开更多
关键词 self-elevating platform leg joint dynamic stress stress amplitude improvement
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Parameter Self - Learning of Generalized Predictive Control Using BP Neural Network
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作者 陈增强 袁著祉 王群仙 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期54-56,共3页
This paper describes the self—adjustment of some tuning-knobs of the generalized predictive controller(GPC).A three feedforward neural network was utilized to on line learn two key tuning-knobs of GPC,and BP algorith... This paper describes the self—adjustment of some tuning-knobs of the generalized predictive controller(GPC).A three feedforward neural network was utilized to on line learn two key tuning-knobs of GPC,and BP algorithm was used for the training of the linking-weights of the neural network.Hence it gets rid of the difficulty of choosing these tuning-knobs manually and provides easier condition for the wide applications of GPC on industrial plants.Simulation results illustrated the effectiveness of the method. 展开更多
关键词 generalized PREDICTIVE CONTROL self - tuning CONTROL self - LEARNING CONTROL neural networks BP algorithm .
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Self - Crosslinking Behavior of Self - Emulsion Water - Based Polyure-thane Coating Agents
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作者 林萍 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期50-53,共4页
The relation between structures and properties of polyurethane are investigated by modern physical and chemical methods.The results obtained are as follows:the effects of the content of self-crosslinking agent on the ... The relation between structures and properties of polyurethane are investigated by modern physical and chemical methods.The results obtained are as follows:the effects of the content of self-crosslinking agent on the properties of polyurethane,i.e.,dispersion stability,dynamical viscoelasticity and mechanical properties are discussed.It is found that the optimum molar ratio of epichlorohydrin and diethylenetriamine is 1:2.A mois- 展开更多
关键词 POLYURETHANE self - CROSSLINKING dynamical VISCOELASTICITY coated FABRICS .
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Culture Self- Consciousness in Transmission of Chinese Philosophy from the Perspective of English Globalization -- Taking the Belt and Road Initiative for Example
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作者 Wang Yan Shi Wenjun 《学术界》 CSSCI 北大核心 2018年第3期273-282,共10页
The Belt and Road Initiative contains the aspiration of Chinese nation to pursue ideological freedom and desire of strengthening international exchanges and cooperation. This paper takes the Belt and Road Initiative f... The Belt and Road Initiative contains the aspiration of Chinese nation to pursue ideological freedom and desire of strengthening international exchanges and cooperation. This paper takes the Belt and Road Initiative for example,emphasizing the interpretation of the inheritance and development of Chinese culture so as to study the importance of Culture Self-Consciousness in Chinese Philosophy,in the context of English globalization. That is to say,this paper stresses the spirits and the stand of nation 's demonstration on pursuing peace,cooperation and sustainable development in the civilization continuity from traditional China to the contemporary China,with practical philosophic view. 展开更多
关键词 English globalization Chinese PHILOSOPHY CULTURE self - CONSCIOUSNESS thebelt and ROAD INITIATIVE
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住院医师规范化培训Self-study模式的实践与探索 被引量:7
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作者 余情 郑玉英 +2 位作者 阎作勤 李妍莹 朱蓁蓁 《中国毕业后医学教育》 2017年第1期20-22,43,共4页
参考美国毕业后医学教育认证委员会(ACGME)住院医师6大核心能力和加拿大皇家内外科学院(The Royal College of Physicians and Surgeons of Canada)Can MEDS住院医师能力框架的住院医师规范化培训评价指标所设立的住院医师规范化培训Sel... 参考美国毕业后医学教育认证委员会(ACGME)住院医师6大核心能力和加拿大皇家内外科学院(The Royal College of Physicians and Surgeons of Canada)Can MEDS住院医师能力框架的住院医师规范化培训评价指标所设立的住院医师规范化培训Self-study方法,以各联盟医院的住院医师规范化培训管理机构及内科、外科、全科、麻醉科、医学影像科住院医师规范化培训专业基地为评估对象。评估内容:涉及管理机构标准及专业基地项目标准的各评估指标共计140项。对140个评估项目开展现况调研、缺陷查找、设定目标、持续改进的自我评估流程,旨在探讨Self-study模式在住院医师规范化培训中的实践与效果。评估结果显示:在140项评估指标中,完全达标的为132项,部分达标需要完善的有5项,未达标需要计划启动的有3项,总体达标率为94.3%。通过本次Self-study的自我评估发现:中国的住院医师规范化培训急需建立一整套既与国际接轨又符合我国国情的住院医师规范化培训质量控制与综合评估体系。 展开更多
关键词 住院医师规范化培训 self-STUDY 持续改进 实践
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Where Have Network-based Self-learning Classes Gone?——Reflections & Expectations on the Employment of Network-based Self-learning Classes
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作者 吴雪茵 《海外英语》 2012年第18期279-280,共2页
To respond to the further development of college English reforms,many universities employed network-based selflearning classes to aid the traditional classroom teaching,especially in teaching listening,but as time wen... To respond to the further development of college English reforms,many universities employed network-based selflearning classes to aid the traditional classroom teaching,especially in teaching listening,but as time went by,some universities gradually gave them up.The paper intends to reflect on the employment of network-based self-learning listening classes,analyz ing the learning with and without its aid,and meanwhile introduce the need to re-employ it,and discuss how we can improve the network-based self-learning classes to help with students' listening. 展开更多
关键词 NETWORK-BASED self-LEARNING listening improvement
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基于改进YOLOv7-tiny算法的多种类不均衡样本水稻害虫检测
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作者 李鑫 南新元 《山东农业科学》 北大核心 2024年第6期133-142,共10页
为实现基于机器视觉的田间水稻害虫检测,本研究结合IP102农业害虫数据集及网络资源,建立了含有26类标签的不均衡样本水稻害虫数据集;改进YOLOv7-tiny单阶段目标检测算法,以部分卷积PConv作为主要卷积核,结合极化自注意力机制(Polarized ... 为实现基于机器视觉的田间水稻害虫检测,本研究结合IP102农业害虫数据集及网络资源,建立了含有26类标签的不均衡样本水稻害虫数据集;改进YOLOv7-tiny单阶段目标检测算法,以部分卷积PConv作为主要卷积核,结合极化自注意力机制(Polarized Self-Attention),将提取到的特征进行复杂双向多尺度特征融合,建立了适合多种类不均衡样本的水稻害虫检测模型。结果表明,在加入迁移学习和多尺度训练的条件下,改进后的YOLOv7-tiny检测算法在自建水稻害虫数据集的平均检测精度达到96.4%,单张图片的检测时间为8.8 ms,模型大小为9 055 kb,可实现对田间水稻害虫的快速准确识别,为水稻害虫的智能化检测和防治提供了技术支持。 展开更多
关键词 水稻害虫检测 改进YOLOv7-tiny算法 部分卷积 极化自注意力机制 特征融合 迁移学习
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一种自复位摇摆墙的改进Bouc-Wen滞回模型
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作者 苏醒 阎石 +1 位作者 付江监 孙祥磊 《防灾减灾工程学报》 CSCD 北大核心 2024年第1期39-49,201,共12页
Bouc-Wen模型是一种可表征结构及构件刚度、强度退化等的多功能非线性光滑滞回模型,可广泛应用于各类结构滞回行为的描述。自复位摇摆墙(Self-centering rocking wall, SCRW)结构由于其优越的抗震和自复位性能,滞回曲线呈“旗帜型”。... Bouc-Wen模型是一种可表征结构及构件刚度、强度退化等的多功能非线性光滑滞回模型,可广泛应用于各类结构滞回行为的描述。自复位摇摆墙(Self-centering rocking wall, SCRW)结构由于其优越的抗震和自复位性能,滞回曲线呈“旗帜型”。为了更好地表征这种“旗帜型”滞回特性,在Bouc-Wen模型的基础上,建立一种具有较高精度和较好实用性的改进Bouc-Wen滞回模型。改进的Bouc-Wen模型参数是决定结构滞回性能力学特征的关键。由于该模型参数众多且选择范围不明确,为适应该类模型参数高效识别的需求,通过在MATLAB/Simulink环境中搭建程序框图,实现了对该理论模型控制参数的定性及定量分析,并运用遗传算法对10个SCRW试验结果进行参数识别,对识别结果进行统计分析,建立各参数与滞回曲线关键点的关系式,基于统计结果给出了各参数的建议取值范围;最后,通过SCRW拟静力试验对改进的滞回模型和参数取值范围进行了验证。结果表明:这种单自由度改进的Bouc-Wen滞回模型能较好地反映SCRW在往复荷载作用下无残余变形和强度、刚度退化特点的“旗帜型”滞回特性。所提出的参数取值范围显著提升了改进Bouc-Wen模型的识别精度与效率,识别过程对类似模型的参数识别具有参考价值。 展开更多
关键词 自复位摇摆墙 “旗帜形”滞回特性 改进Bouc-Wen模型 模型参数识别 拟静力试验
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基于IMHSA-MSCNN-BiLSTM的风机轴承故障诊断 被引量:1
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作者 张家安 邓强 +1 位作者 马增强 李志军 《电子测量技术》 北大核心 2024年第7期170-176,共7页
由于风力发电机组的非平稳运行条件和周围恶劣的工作环境,风机轴承故障振动脉冲特征易被随机噪声干扰所淹没,这给准确检测滚动轴承故障造成了挑战。为了降低随机干扰对后续特征提取的影响和算法复杂度,提出了一种改进多头自注意力机制(I... 由于风力发电机组的非平稳运行条件和周围恶劣的工作环境,风机轴承故障振动脉冲特征易被随机噪声干扰所淹没,这给准确检测滚动轴承故障造成了挑战。为了降低随机干扰对后续特征提取的影响和算法复杂度,提出了一种改进多头自注意力机制(IMHSA)-多尺度卷积网络(MSCNN)-双向长短期记忆网络(BiLSTM)的风机轴承故障诊断方法。首先,由周期空洞自注意力和局部自注意力组成的IMHSA对特征进行增强,以减少随机干扰影响及特征增强过程中的时间消耗;然后,利用MSCNN-BiLSTM网络提取故障信号中的空间特征与长期依赖特征;最后,经全连接层和Softmax层输出风机轴承故障诊断结果,并采用实验台滚动轴承实际运行数据进行算例分析,通过与领域内其他同类方法的对比,验证了所提方法的有效性和优越性。 展开更多
关键词 风机轴承故障诊断 改进多头自注意力机制 多尺度卷积网络 双向长短期记忆网络
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Optimal Deployment with Self-Healing Movement Algo-rithm for Particular Region in Wireless Sensor Network
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作者 Fan ZHU Hongli LIU +1 位作者 Shugang LIU Jie ZHAN 《Wireless Sensor Network》 2009年第3期212-221,共10页
Optimizing deployment of sensors with self-healing ability is an efficient way to solve the problems of cov-erage, connectivity and the dead nodes in WSNs. This work discusses the particular relationship between the m... Optimizing deployment of sensors with self-healing ability is an efficient way to solve the problems of cov-erage, connectivity and the dead nodes in WSNs. This work discusses the particular relationship between the monitoring range and the communication range, and proposes an optimal deployment with self-healing movement algorithm for closed or semi-closed area with irregular shape, which can not only satisfy both coverage and connectivity by using as few nodes as possible, but also compensate the failure of nodes by mobility in WSNs. We compute the maximum efficient range of several neighbor sensors based on the dif-ferent relationships between monitoring range and communication range with consideration of the complex boundary or obstacles in the region, and combine it with the Euclidean Minimum Spanning Tree (EMST) algorithm to ensure the coverage and communication of Region of Interest (ROI). Besides, we calculate the location of dead nodes by Geometry Algorithm, and move the higher priority nodes to replace them by an-other Improved Virtual Force Algorithm (IVFA). Eventually, simulation results based-on MATLAB are presented, which do show that this optimal deployment with self-healing movement algorithm can ensure the coverage and communication of an entire region by requiring the least number of nodes and effectively compensate the loss of the networks. 展开更多
关键词 Optimal DEPLOYMENT self-HEALING MOVEMENT PARTICULAR REGION Euclidean Minimum SPANNING Tree (EMST) improved Virtual Force Algorithm (IVFA)
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全媒体时代高校红色文化的传播现状及策略研究--以井冈山为例
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作者 肖楠 尤亭亭 樊玉华 《文化创新比较研究》 2024年第1期68-71,共4页
习近平总书记在党的二十大报告中对文化自信自强提出新的要求,“全面建设社会主义现代化国家,必须坚持中国特色社会主义发展道路,增强文化自信,围绕举旗帜、聚民心、育新人、兴文化、展形象建设社会主义文化强国”。红色文化作为中国文... 习近平总书记在党的二十大报告中对文化自信自强提出新的要求,“全面建设社会主义现代化国家,必须坚持中国特色社会主义发展道路,增强文化自信,围绕举旗帜、聚民心、育新人、兴文化、展形象建设社会主义文化强国”。红色文化作为中国文化的重要组成部分,如何在全媒体背景下提高高校传播效果,提升当代大学生对红色文化的认同感,是亟待研究的重要课题。该文以井冈山红色精神为例,在梳理原有传播途径的基础之上,深入井冈山开展现状调研,剖析在高校思政课中红色文化传播受阻的主要原因,根据当前全媒体时代特征提出红色文化传播的新模式,加强全媒体传播体系建设,推动高校思政教育课程改革,从而实现红色文化在高校的有效传播。 展开更多
关键词 文化自信自强 红色精神 全媒体时代 文化传播体系 社会主义核心价值观 思政教育课程改革
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基于改进J-A模型的气动肌肉迟滞建模及其补偿控制 被引量:4
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作者 于晓文 杨辉 郝丽娜 《液压与气动》 北大核心 2018年第7期19-23,共5页
针对气动肌肉非对称迟滞现象,采用改进Jiles-Atherton(J-A)模型来对其进行描述,并利用自适应权重粒子群来对模型所需参数进行辨识;通过与实验数据进行对比,对所建模型精度进行验证。基于所建迟滞模型,进而提出一种积分逆迟滞补偿器,通... 针对气动肌肉非对称迟滞现象,采用改进Jiles-Atherton(J-A)模型来对其进行描述,并利用自适应权重粒子群来对模型所需参数进行辨识;通过与实验数据进行对比,对所建模型精度进行验证。基于所建迟滞模型,进而提出一种积分逆迟滞补偿器,通过将其引入到PID控制系统中,实现对气动肌肉的迟滞补偿控制。仿真结果表明,引入迟滞补偿器后显著提高了对气动肌肉的控制精度,验证了所提迟滞补偿器的有效性。 展开更多
关键词 气动肌肉 改进Jiles-Atherton模型 自适应权重粒子群 迟滞补偿控制
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一种基于改进自忆性原理的西太平洋副热带高压脊线指数动力-统计模型及其预报实验 被引量:2
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作者 洪梅 张韧 +3 位作者 冯芒 马晨晨 余丹丹 郝志男 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2016年第7期2362-2376,共15页
针对西太平洋副热带高压中长期预报不准确的问题,基于动力系统反演思想和改进自忆性原理等途径建立了副高脊线指数的动力预报模型.本文创新性地引入了最大李雅普诺夫指数改进了传统的自忆性函数,使其对副热带高压之类的混沌非线性系统... 针对西太平洋副热带高压中长期预报不准确的问题,基于动力系统反演思想和改进自忆性原理等途径建立了副高脊线指数的动力预报模型.本文创新性地引入了最大李雅普诺夫指数改进了传统的自忆性函数,使其对副热带高压之类的混沌非线性系统更加具有针对性,较好地克服了预报初值单一性问题;并根据实际观测资料重构的动力系统作为其动力核,克服了传统自忆性方程动力核设置较为简单的问题.用建立的副热带高压脊线指数动力预报模型实现了副高南北位置的中长期预报,通过了副高异常年份和正常年份的多次实验,可以发现模型在25天以内的预报效果很好,相关系数能达到0.80左右,相对误差控制在8%以下,证明了改进的模型具有较好的中长期预报效果.另外还将此模型推广到对副热带高压的面积指数和西脊点指数的预报,也取得了较好的预报效果,证明此方法适合于副热带高压的整体预报.鉴于西太副高发生发展机理的复杂性和预报的困难性,本文为副高等复杂天气系统的预报探索了新的方法思路. 展开更多
关键词 副热带高压 改进自忆性原理 动力模型重构 中长期预报 最大李雅普诺夫指数
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