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Unstabilized Self-amalgamation of a Heegaard Splitting along Disks
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作者 Liang Liang Lei Feng-chun Li Feng-ling 《Communications in Mathematical Research》 CSCD 2016年第2期117-121,共5页
In this paper, we prove that a self-amalgamation of a strongly irreducible Heegaard splitting along disks is unstabilized.
关键词 Heegaard splitting self-amalgamation unstabilized
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MERGING AND SPLITTING SECOND-ORDER SELF-SIMILAR PROCESSES (TRAFFICS) 被引量:2
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作者 施建俊 诸鸿文 《Journal of Shanghai Jiaotong university(Science)》 EI 2000年第2期33-37,共5页
Recent traffic measurements in corporate LANs, Variable Bit Rate (VBR) video sources, ISDN control channels, and other communication systems, have indicated traffic behavior of self similar nature, which has implicati... Recent traffic measurements in corporate LANs, Variable Bit Rate (VBR) video sources, ISDN control channels, and other communication systems, have indicated traffic behavior of self similar nature, which has implications for design, control and analysis of high speed networks. Merging and splitting are two basic networking operations. This paper gave the necessary and sufficient conditions for that merging of second order self similar traffic streams also results in a second order self similar stream. It shows that splitting traffic streams of the second order self similar stream are still self similar streams by the independent splitting operation. 展开更多
关键词 self similar TRAFFIC MERGING TRAFFIC splitTING TRAFFIC Document code:A
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Ti^(3+) self-doped TiO_2 photoelectrodes for photoelectrochemical water splitting and photoelectrocatalytic pollutant degradation
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作者 Chaoyi Wu Zhenggang Gao +5 位作者 Shanmin Gao Qingyao Wang Hui Xu Zeyan Wang Baibiao Huang Ying Dai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第4期726-733,共8页
To improve the harvesting of visible light and reduce the recombination of photogenerated electrons and holes, Ti3+ self-doped TiO2 nanoparticles were synthesized and assembled into photoanodes with high visible light... To improve the harvesting of visible light and reduce the recombination of photogenerated electrons and holes, Ti3+ self-doped TiO2 nanoparticles were synthesized and assembled into photoanodes with high visible light photoelectrochemical properties. X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectra, electron resonance spectroscopy and energy dispersive X-ray spectra were used to characterize the structure, crystallinity, morphology and other properties of the obtained nanoparticles. UV-visible diffuse reflectance spectra showed that the Ti3+ self-doped TiO2 nanoparticles had a strong absorption between 400 and 800 nm. Moreover, when hydrothermal treatment time was prolonged to 22 h, the heterogeneous junction was formed between the anatase and rutile TiO2, where the anatase particles exposed highly active {001} facets. Under visible light irradiation, the Ti3+ self-doped TiO2 electrode exhibited an excellent photoelectrocatalytic degradation of rhodamine B (RhB) and water splitting performance. Intriguingly, by selecting an appropriate hydrothermal time, the high photoconversion efficiency of 1.16% was achieved. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 Ti3+ self-doping TITANIUM PHOTOANODE Water splitting Photoelectrocatalytic properties
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Self-Adaptive Algorithms for the Split Common Fixed Point Problem of the Demimetric Mappings
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作者 Xinhong Chen Yanlai Song +1 位作者 Jianying He Liping Gong 《Journal of Applied Mathematics and Physics》 2019年第10期2187-2199,共13页
The split common fixed point problem is an inverse problem that consists in finding an element in a fixed point set such that its image under a bounded linear operator belongs to another fixed-point set. In this paper... The split common fixed point problem is an inverse problem that consists in finding an element in a fixed point set such that its image under a bounded linear operator belongs to another fixed-point set. In this paper, we present new iterative algorithms for solving the split common fixed point problem of demimetric mappings in Hilbert spaces. Moreover, our algorithm does not need any prior information of the operator norm. Weak and strong convergence theorems are given under some mild assumptions. The results in this paper are the extension and improvement of the recent results in the literature. 展开更多
关键词 HILBERT Space Demimetric Mapping split Common Fixed Point PROBLEM self-ADAPTIVE Algorithm
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小样本下基于SCResNeSt50和迁移学习的齿轮故障诊断
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作者 刘杰 郭泽锋 杨娜 《沈阳工业大学学报》 北大核心 2026年第1期110-119,共10页
【目的】现有研究针对不同设备间迁移学习的齿轮故障诊断仍存在不足,尤其是在小样本条件下,诊断准确率仍待提高。为此,提出一种结合自校准卷积分散注意力网络(SCResNeSt50)模型与迁移学习策略的小样本齿轮故障诊断方法。【方法】基于连... 【目的】现有研究针对不同设备间迁移学习的齿轮故障诊断仍存在不足,尤其是在小样本条件下,诊断准确率仍待提高。为此,提出一种结合自校准卷积分散注意力网络(SCResNeSt50)模型与迁移学习策略的小样本齿轮故障诊断方法。【方法】基于连续小波变换对齿轮信号进行时频分析,生成时频图作为模型输入。采用ResNeSt网络结构融合分散注意力机制与自校准卷积改进传统卷积神经网络对时频图的线性处理方式,即使用自校准卷积替代ResNeSt模块中的常规卷积,以实现自适应响应校准和多尺度特征编码,从而扩大感受野并增强故障特征表征能力。采用迁移学习策略,通过微调源域预训练模型的分类器参数,并冻结特征提取层,以实现目标任务的有效适配,同时保留源模型的通用知识和特征表示,提高小样本条件下的齿轮故障诊断准确率。【结果】在东南大学齿轮箱数据集与康涅狄格大学齿轮数据集上进行实验,验证了方法的有效性。实验包括变工况迁移学习与跨数据集迁移学习两类场景,并与现有故障诊断方法进行对比分析。结果表明,在变工况迁移学习实验中,目标域诊断准确率分别达到98.7%和98.9%;在东南大学数据集向康涅狄格大学数据集的迁移实验中,当目标域训练集中每种齿轮状态的样本量分别为25、20、16、12、8及6个时,诊断准确率分别达到98.1%、98.1%、97.8%、97.5%、96.5%及93.1%。【结论】方法在多个实验中均取得优于其他方法的诊断准确率,表明改进的自校准卷积有效提升了齿轮故障特征的表征能力,而迁移学习策略在小样本条件下显著增强了故障诊断的可靠性。该研究为小样本条件下的齿轮故障诊断提供了可行的解决方案,推动了智能故障诊断技术的发展。 展开更多
关键词 小样本 故障诊断 齿轮 自校准卷积 分散注意力机制 迁移学习 源域 目标域
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自持续IRS辅助速率拆分多址系统的资源分配方案
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作者 赵新宇 唐菁敏 宋耀莲 《重庆邮电大学学报(自然科学版)》 北大核心 2026年第1期39-48,共10页
为增强速率拆分多址(rate-splitting multiple access,RSMA)系统中智能反射面(intelligent reflecting surface,IRS)部署的灵活性,同时提高RSMA系统能量效率,建立了自持续IRS辅助的RSMA下行链路系统模型。模型以最大化系统能量效率为目... 为增强速率拆分多址(rate-splitting multiple access,RSMA)系统中智能反射面(intelligent reflecting surface,IRS)部署的灵活性,同时提高RSMA系统能量效率,建立了自持续IRS辅助的RSMA下行链路系统模型。模型以最大化系统能量效率为目标,在能量收集和离散相移约束下,建立了一个速率分配、波束成形、模式选择和离散相移的联合优化问题,并将问题分解为两个子问题,交替迭代优化直至收敛。针对速率分配和波束成形子问题,采用半正定松弛算法(semidefinite relaxation,SDR)、逐次凸逼近(successive convex approximation,SCA)算法和Dinkelbach算法求解;针对模式选择和离散相移子问题,采用SCA算法和罚函数法求解。仿真结果表明,相比于基线方案,提出的优化方案具有更好的性能。 展开更多
关键词 智能反射面 速率拆分多址 离散相移 自持续智能反射面
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DnaB Split Intein高表达载体及其介导的环肽库构建
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作者 蔺增曦 王胜兰 +1 位作者 杨秀山 杨克迁 《生物工程学报》 CAS CSCD 北大核心 2008年第11期1924-1930,共7页
以pET28a为起始质粒,构建高表达DnaB split intein的重组质粒。将质粒pVmut上的编码IntC-dnaB-N-IntN片段克隆至pET28a,得到表达载体pEV,在T7启动子的作用下可使融合DnaB split intein大量表达;并在split intein介导下发生催化DnaB-N的... 以pET28a为起始质粒,构建高表达DnaB split intein的重组质粒。将质粒pVmut上的编码IntC-dnaB-N-IntN片段克隆至pET28a,得到表达载体pEV,在T7启动子的作用下可使融合DnaB split intein大量表达;并在split intein介导下发生催化DnaB-N的剪接反应,生成环化的DnaB-N蛋白。将合成的包含随机编码5肽的大小为115 bp的片段插入质粒pEV DnaB-N位置,转化大肠杆菌后得到一个编码含有6肽(含5个随机氨基酸和1个Cys)的包含约103个克隆的表达载体pEV-IS库。随机挑取20个克隆,测序证明均按正确阅读框插入了不同的小肽序列;挑取其中9个克隆进行表达,结果表明可产生大量的融合蛋白,90%的融合蛋白在16oC表达20 h后发生体内剪接。将在30oC表达3 h的融合蛋白用His柱进行纯化,通过MALDI-TOF质谱检测到了目的环肽分子量。 展开更多
关键词 split SSP DNAB mini—intein 环肽库 自我剪接
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Facile synthesis of free-standing nickel chalcogenide electrodes for overall water splitting 被引量:2
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作者 Haonan Ren Zheng-Hong Huang +3 位作者 Zhiyu Yang Shujun Tang Feiyu Kang Ruitao Lv 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1217-1222,共6页
Developing high-performance noble metal-free and free-standing catalytic electrodes are crucial for overall water splitting. Here, nickel sulfide(NiS) and nickel selenide(Ni Se) are synthesized on nickel foam(NF... Developing high-performance noble metal-free and free-standing catalytic electrodes are crucial for overall water splitting. Here, nickel sulfide(NiS) and nickel selenide(Ni Se) are synthesized on nickel foam(NF) with a one-pot solvothermal method and directly used as free-standing electrodes for efficiently catalyzing hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) in alkaline solution.In virtue of abundant active sites, the NiS/NF and the NiS e/NF electrodes can deliver a current density of 10 m A cmat only 123 m V, 137 m V for HER and 222 m V, 271 m V for OER. Both of the hierarchical NiS/NF and Ni Se/NF electrodes can serve as anodes and cathodes in electrocatalytic overall watersplitting and can achieve a current density of 10 m A cmwith an applied voltage of.59 V and 1.69 V,respectively. The performance of as-obtained NiS/NF||NiS/NF is even close to that of the noble metalbased Pt/C/NF||IrO/NF system. 展开更多
关键词 Overall water splitting Nickel chalcogenide self-standing SOLVOTHERMAL Active sites
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Evolution of dark solitons in the presence of Raman gain and self-steepening effect 被引量:1
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作者 于宇 贾维国 +2 位作者 闫青 门克内木乐 张俊萍 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期366-372,共7页
Based on the equation satisfied by optical pulse that is a slowly varying function, the higher-order nonlinear Schr o¨dinger equation(NLSE) including Raman gain and self-steepening effect is deduced in detail, an... Based on the equation satisfied by optical pulse that is a slowly varying function, the higher-order nonlinear Schr o¨dinger equation(NLSE) including Raman gain and self-steepening effect is deduced in detail, and a new Raman gain function is defined. By using the split-step Fourier method, the influence of the combined effect between Raman gain and self-steepening on the propagation characteristic of dark solitons is simulated in the isotropic fiber. The results show that gray solitons can be symmetrically formed by high order dark soliton, however self-steepening effect will inhibit the formation mechanism through the phenomenon that gray solitons are produced only in the trailing edge of the central black soliton. Meanwhile, the Raman gain changes the propagation characteristic of optical soliton and inhibits the self-steepening effect, resulting in the broadening of pulse width and the decreasing of pulse offset. 展开更多
关键词 split-step Fourier method self-steepening effect dark soliton propagation characteristic
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An Identifier-Based Network Access Control Mechanism Based on Locator/Identifier Split
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作者 Rui TU Jinshu SU Ruoshan KONG 《International Journal of Communications, Network and System Sciences》 2009年第7期641-644,共4页
Legacy IP address-based access control has met many challenges, because the network nodes cannot be identified accurately based on their variable IP addresses. “Locator/Identifier Split” has made it possible to buil... Legacy IP address-based access control has met many challenges, because the network nodes cannot be identified accurately based on their variable IP addresses. “Locator/Identifier Split” has made it possible to build a network access control mechanism based on the permanent identifier. With the support of “Locator/Identifier Split” routing and addressing concept, the Identifier-based Access Control (IBAC) makes net-work access control more accurate and efficient, and fits for mobile nodes’ access control quite well. Moreover, Self-verifying Identifier makes it possible for the receiver to verify the packet sender’s identity without the third part authentication, which greatly reduces the probability of “Identifier Spoofing”. 展开更多
关键词 ACCESS Control Locator/Identifier split IBAC self-Verifying IDENTIFIER IDENTIFIER SPOOFING
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大电流密度电解水制氢自支撑催化电极的研究进展 被引量:2
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作者 何小波 赵艳玲 +1 位作者 银凤翔 李国儒 《常州大学学报(自然科学版)》 2025年第2期17-28,共12页
开发和设计具有高活性和耐久性的催化电极对于电解水制氢技术的发展具有重要作用。自支撑催化电极作为一种优异的电极备受关注。文章以满足大电流密度(500 mA/cm^(2))电解水制氢自支撑催化电极的研究为目标,阐述了构建晶格缺陷,掺杂异... 开发和设计具有高活性和耐久性的催化电极对于电解水制氢技术的发展具有重要作用。自支撑催化电极作为一种优异的电极备受关注。文章以满足大电流密度(500 mA/cm^(2))电解水制氢自支撑催化电极的研究为目标,阐述了构建晶格缺陷,掺杂异质杂原子,构建异质结界面以及“超疏气”微纳米结构等几种不同策略在析氢反应(HER)和析氧反应(OER)的近期研究进展。最后,从优化导电基底,加深理论计算,制备高耐久性和宽pH应用范围的催化电极方面,提出了电解水催化电极未来发展的方向与挑战,以期对高性能和稳定型的HER/OER催化电极的设计提供指导。 展开更多
关键词 制氢 水分解 催化 自支撑催化电极 大电流密度
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基于SC-ResNeSt及频域格拉姆角场的滚动轴承故障诊断方法 被引量:2
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作者 王海涛 郭一帆 史丽晨 《计算机集成制造系统》 北大核心 2025年第4期1272-1286,共15页
在实际的工程环境中,滚动轴承通常在强噪声、变负载的条件下工作,针对传统深度学习模型在滚动轴承的故障诊断领域中面临着抗噪性、模型泛化性、鲁棒性差等问题,提出一种基于深度残差分散自校准卷积网络(SC-ResNeSt)和频域格拉姆角场(GAF... 在实际的工程环境中,滚动轴承通常在强噪声、变负载的条件下工作,针对传统深度学习模型在滚动轴承的故障诊断领域中面临着抗噪性、模型泛化性、鲁棒性差等问题,提出一种基于深度残差分散自校准卷积网络(SC-ResNeSt)和频域格拉姆角场(GAF)的滚动轴承故障诊断新方法。首先,利用GAF编码将振动信号转换为二维图像,并进行二维离散傅里叶变换(2D-DFT)将该图像从空间域转换到频域;其次,因为传统的卷积层缺少动态变化的感受野来提取更具代表性的特征,所以在分散注意力网络(ResNeSt)的基础上引入了自校准卷积模块(SC),提出了一种新的网络模型,即SC-ResNeSt;最后,以频域空间中的GAF作为SC-ResNeSt的输入,故障特征提取完成后,由Softmax分类器完成对故障特征的分类。为验证模型性能,采用美国凯斯西储大学(CWRU)轴承数据集和德国帕博德恩大学(PU)轴承数据集进行测试,实验结果表明所提方法在两种数据集中都取得了较高的故障识别准确率,从而证明了其良好的抗噪性、泛化性以及实用性。 展开更多
关键词 自校准卷积 分散注意力机制 格拉姆角场 故障诊断
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Effects of CuO Nanoparticles on Microstructure,Physical,Mechanical and Thermal Properties of Self-Compacting Cementitious Composites 被引量:2
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作者 Ali Nazari Shadi Riahi 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第1期81-92,共12页
In the present study,split tensile strength of self-compacting concrete with different amount of CuO nanoparticles has been investigated.CuO nanoparticles with the average particle size of 15 nm were added partially t... In the present study,split tensile strength of self-compacting concrete with different amount of CuO nanoparticles has been investigated.CuO nanoparticles with the average particle size of 15 nm were added partially to self compacting concrete and split tensile strength of the specimens has been measured.The results indicate that CuO nanoparticles are able to improve the split tensile strength of self compacting concrete and recover the negative effects of polycarboxylate superplasticizer on split tensile strength.CuO nanoparticle as a partial replacement of cement up to 4 wt% could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH)2 amount at the early ages of hydration.The increase of the CuO nanoparticles more than 4 wt% causes the decrease of the split tensile strength because of unsuitable dispersion of nanoparticles in the concrete matrix.Accelerated peak appearance in conduction calorimetry tests,more weight loss in thermogravimetric analysis and more rapid appearance of related peaks to hydrated products in X-ray diffraction(XRD) results all also indicate that CuO nanoparticles up to4 wt% could improve the mechanical and physical properties of the specimens.Finally,CuO nanoparticles could improve the pore structure of concrete and shift the distributed pores to harmless and few-harm pores. 展开更多
关键词 self-compacting concrete(SCC) CuO nanoparticles split tensile strength Thermogravimetric analysis(TGA) X-ray diffraction(XRD) Pore structure
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Generation of time-dependent ultra-short optical pulse trains in the presence of self-steepening effect 被引量:1
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作者 钟先琼 向安平 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期624-629,共6页
Starting from the extended nonlinear Schrodinger equation in which the self-steepening effect is included, the evolution and the splitting processes of continuous optical wave whose amplitude is perturbed into time re... Starting from the extended nonlinear Schrodinger equation in which the self-steepening effect is included, the evolution and the splitting processes of continuous optical wave whose amplitude is perturbed into time related ultra-short optical pulse trains in an optical fibre are numerically simulated by adopting the split-step Fourier algorithm. The results show that the self-steepening effect can cause the characteristic of the pulse trains to vary with time, which is different from the self-steepening-free case where the generated pulse trains consist of single pulses which are identical in width, intensity, and interval, namely when pulses move a certain distance, they turn into the pulse trains within a certain time range. Moreover, each single pulse may split into several sub-pulses. And as time goes on, the number of the sub-pulses will decrease gradually and the pulse width and the pulse intensity will change too. With the increase of the self-steepening parameter, the distance needed to generate time-dependent pulse trains will shorten. In addition, for a large self-steepening parameter and at the distance where more sub-pulses appear, the corresponding frequency spectra of pulse trains are also wider. 展开更多
关键词 nonlinear optics self-steepening effect ultra-short optical pulse trains split-step Fourier algorithm optical perturbation
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时空余弦多高斯关联部分相干脉冲光束的传输特性
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作者 焦帅 丁超亮 +2 位作者 于丹 沈礼 亓协兴 《光学仪器》 2025年第4期1-12,共12页
基于部分相干光场的相干理论,介绍了一类新的具有空间余弦–多高斯和时间余弦–多高斯关联的部分相干脉冲光束,即时空余弦多高斯关联部分相干(spatiotemporal cosine-multi-Gaussian correlation partially coherent,STCMGCPC)脉冲光束... 基于部分相干光场的相干理论,介绍了一类新的具有空间余弦–多高斯和时间余弦–多高斯关联的部分相干脉冲光束,即时空余弦多高斯关联部分相干(spatiotemporal cosine-multi-Gaussian correlation partially coherent,STCMGCPC)脉冲光束。利用广义惠更斯–菲涅尔衍射积分公式,推导出了STCMGCPC脉冲光束通过时空ABCD光学系统的解析传输公式。以静止的水作为色散介质的实例,研究了STCMGCPC脉冲光束的时空强度演化特性。研究结果表明,STCMGCPC脉冲光束同时表现出时空自分裂和自聚焦现象,出现这些现象的物理原因是脉冲光束特殊的时空相干结构和脉冲啁啾的相互作用。该研究结果在水下激光通信和成像领域具有潜在应用价值。 展开更多
关键词 相干性 时空强度 部分相干脉冲光束 自分裂
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基于多路激励和金字塔切分注意力的鸟类行为识别 被引量:1
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作者 邓抒憧 陈爱斌 戴子健 《应用科学学报》 北大核心 2025年第1期154-168,共15页
针对传统行为识别方法在处理复杂鸟类行为模式时存在辨识率低、误判率高等问题,提出了一种基于多路激励模块和金字塔切分注意力的改进3D残差网络的深度学习模型。利用帧间差分法有效减轻计算负担,在精确保留关键时空信息的同时提高了识... 针对传统行为识别方法在处理复杂鸟类行为模式时存在辨识率低、误判率高等问题,提出了一种基于多路激励模块和金字塔切分注意力的改进3D残差网络的深度学习模型。利用帧间差分法有效减轻计算负担,在精确保留关键时空信息的同时提高了识别精度。引入多路激励模块改进原有残差块,使模型能够精准捕捉细微运动行为特征,解决了鸟类复杂动态行为识别易混淆的问题。以3D金字塔切分注意力替换原有3D卷积层,实现对不同尺度鸟类行为特征的有效捕获。在自建鸟类行为视频数据集上进行实验,对常见鸟类行为的识别准确率达到90.48%,显著优于基准模型与其他现有流行行为识别网络,证明了所提模型对复杂鸟类行为识别的有效性。 展开更多
关键词 鸟类行为识别 多路激励 金字塔切分注意力 帧间差分法 自建数据集
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求解高光谱解混的三算子分裂方法
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作者 董云达 张园园 李一怡 《郑州大学学报(理学版)》 CAS 北大核心 2025年第2期85-88,共4页
对于高光谱解混问题,提出了一个相应的三算子单调包含和求解该问题的一个分裂方法,其中邻近因子可以自适应选取。该方法还可用于求解更一般的带有线性复合的三算子单调包含问题。数值实验表明,该算法的性能远远超过最近提出的邻近内点方... 对于高光谱解混问题,提出了一个相应的三算子单调包含和求解该问题的一个分裂方法,其中邻近因子可以自适应选取。该方法还可用于求解更一般的带有线性复合的三算子单调包含问题。数值实验表明,该算法的性能远远超过最近提出的邻近内点方法,并且与其变尺度版本相当。 展开更多
关键词 邻近内点法 单调包含 分裂方法 高光谱解混 自适应
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聚甲醛纤维对自密实混凝土工作性能和力学性能影响 被引量:3
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作者 刘恒 贺晶晶 +1 位作者 冯兴国 崔海鹏 《中国农村水利水电》 北大核心 2025年第3期166-171,共6页
针对聚甲醛(POM)纤维自密实混凝土开展性能试验研究,分析纤维几何特性、纤维掺量对自密实混凝土(SCC)的工作性能的与力学性能的影响规律及机理。研究表明:纤维长度一定时,掺量在0.8~2.4 kg/m^(3)范围内增加时,SCC坍落扩展度下降,SCC的... 针对聚甲醛(POM)纤维自密实混凝土开展性能试验研究,分析纤维几何特性、纤维掺量对自密实混凝土(SCC)的工作性能的与力学性能的影响规律及机理。研究表明:纤维长度一定时,掺量在0.8~2.4 kg/m^(3)范围内增加时,SCC坍落扩展度下降,SCC的力学性能呈先增后减的趋势;纤维掺量一定时,纤维长度6~20 mm范围内增大时,SCC坍落扩展度变化不大,SCC力学性能呈先增后减的趋势。掺量1.6 kg/m^(3)、长度12 mm的圆柱状纤维对SCC抗压强度提升幅度最大,较素SCC的28 d强度提升了3.6%;长度12 mm扁平状纤维与长度6 mm圆柱状纤维混杂,掺量为1.6 kg/m^(3)时,SCC的28 d劈裂抗拉强度提高14.52%。POM的掺入,使得对SCC微观结构更为密实,纤维与胶凝体紧密结合可有效吸收破坏产生能量,实现宏观力学性能提升。研究结论可为POM纤维自密实混凝土工程应用提供参考。 展开更多
关键词 自密实混凝土 聚甲醛纤维 坍落扩展度 抗压强度 劈裂抗拉强度 微观结构
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高压绝缘分体式可快速拆卸安装接线套管环网柜的设计与应用
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作者 张锐豪 黄丽华 +4 位作者 李光辉 韩茂龙 陈光伟 佘文标 陈海明 《机电工程技术》 2025年第16期144-148,共5页
为攻克传统环网柜安装效率低、安全风险高的难题,融合多学科前沿原理,将电气绝缘、机械结构、导体连接等技术综合运用,精心设计出高压绝缘分体式可快速拆卸安装接线套管的环网柜,并内置集成自锁装置。在设计电气绝缘时,依据Paschen定律... 为攻克传统环网柜安装效率低、安全风险高的难题,融合多学科前沿原理,将电气绝缘、机械结构、导体连接等技术综合运用,精心设计出高压绝缘分体式可快速拆卸安装接线套管的环网柜,并内置集成自锁装置。在设计电气绝缘时,依据Paschen定律精准选材料;机械结构运用有限元分析优化连接,使部件应力降30%;导体连接采用弹簧触指等实现低损耗、大载流量,搭配智能温湿度控制器控温。经第三方检测,产品多项性能达标。实际应用显示,在城市电网与工业用电场景中,该环网柜故障率较传统产品降低40%,供电可靠性超99.5%,安装效率提升超3倍,停电时长削减约50%,以显著优势为电力系统稳定运行提供有力支撑。 展开更多
关键词 环网柜 高压绝缘 分体式设计 自锁装置 安全防护系统
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架空输电线路无人机自动接地技术研究
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作者 丁思明 周涛 +1 位作者 胡家顺 许兆帅 《自动化与仪表》 2025年第12期134-138,共5页
该文探究基于无人机的架空输电线路接地新方案。针对电网扩大、电压提升后,传统人工登塔检修存在触电、高空坠落风险及效率低的问题,提出无人机分体式自锁挂拆接地线技术。结合理论与实验,研制适配架空线路的挂拆装备,采用分体式设计、... 该文探究基于无人机的架空输电线路接地新方案。针对电网扩大、电压提升后,传统人工登塔检修存在触电、高空坠落风险及效率低的问题,提出无人机分体式自锁挂拆接地线技术。结合理论与实验,研制适配架空线路的挂拆装备,采用分体式设计、重力锁定原理及“夹具型”夹紧锁定结构,确保接地线与导线牢固连接。装置重1.8 kg~2.0 kg,适配26 mm~52 mm分裂子导线及荷载≥2 kg多旋翼无人机。经试验验证,新技术适应性、可靠性良好,能够显著提升检修效率与安全性。 展开更多
关键词 无人机 架空输电线路 分体式自锁接地线 重力锁定 夹具型夹紧结构 挂拆装置
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