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基于改进Super-Twisting滑模观测器的永磁同步电机无传感器控制 被引量:5
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作者 王涛 黄景春 +1 位作者 周行之 金靖 《西南交通大学学报》 北大核心 2025年第2期445-453,共9页
在无传感器控制宽调速范围内,传统super-twisting二阶滑模观测器算法在永磁同步电机中存在转子位置估计误差随速度变化而发生抖动的问题.为减小转子位置估计误差并提升电机调速控制性能,本文基于双曲函数提出一种改进的滑模观测器,并设... 在无传感器控制宽调速范围内,传统super-twisting二阶滑模观测器算法在永磁同步电机中存在转子位置估计误差随速度变化而发生抖动的问题.为减小转子位置估计误差并提升电机调速控制性能,本文基于双曲函数提出一种改进的滑模观测器,并设计定子电阻的在线辨识方案,同时开发扰动电压观测器以在线估计逆变器非线性引起的失真电压;最后,通过电机硬件在环实验测试进行验证.测试结果表明:位置估计误差减小7.6%,速度估计精度提高5.8%. 展开更多
关键词 永磁同步电机 无传感器控制 改进super-twisting算法 定子电阻在线辨识 逆变器非线性补偿
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尿脱落细胞蜡块在尿路上皮癌TWIST1基因甲基化检测中的应用
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作者 张继伟 谭艳佳 《临床与实验病理学杂志》 北大核心 2025年第5期685-687,共3页
目的探讨尿脱落细胞蜡块用于TWIST1基因甲基化检测的临床价值,及用于尿路上皮癌早期筛查的可行性。方法收集22例泌尿系统肿瘤患者术前尿液样本,其中5例用于比较尿脱落细胞和细胞蜡块检测TWIST1基因甲基化结果。结果尿脱落细胞和细胞蜡... 目的探讨尿脱落细胞蜡块用于TWIST1基因甲基化检测的临床价值,及用于尿路上皮癌早期筛查的可行性。方法收集22例泌尿系统肿瘤患者术前尿液样本,其中5例用于比较尿脱落细胞和细胞蜡块检测TWIST1基因甲基化结果。结果尿脱落细胞和细胞蜡块检测TWIST1基因甲基化结果一致性为100%,同时TWIST1和内标基因GAPDH扩增曲线的Ct值之间差异无统计学意义。以病理诊断结果为“金标准”,尿脱落细胞学检查诊断尿路上皮癌的一致性为50.00%,细胞蜡块TWIST1基因甲基化检测的一致性为81.82%。结论尿脱落细胞蜡块可以用于包括膀胱癌在内的尿路上皮癌早期筛查的TWIST1基因甲基化检测。 展开更多
关键词 膀胱癌 尿路上皮癌 细胞蜡块 twist1基因
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TPT1-AS1靶向miR-324/TWIST1轴调控上皮性卵巢癌细胞侵袭、迁移及血管生成的分子机制
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作者 王爱萍 戚莹莹 《细胞与分子免疫学杂志》 北大核心 2025年第6期536-543,共8页
目的探究肿瘤蛋白翻译调控1反义RNA1(TPT1-AS1)靶向miR-324/核转录因子扭曲相关蛋白1(TWIST1)轴调控上皮性卵巢癌(EOC)细胞的增殖、侵袭、迁移及血管生成从而影响卵巢癌(OC)发展的作用机制。方法实时定量PCR检测29例OC灶及癌旁组织样本... 目的探究肿瘤蛋白翻译调控1反义RNA1(TPT1-AS1)靶向miR-324/核转录因子扭曲相关蛋白1(TWIST1)轴调控上皮性卵巢癌(EOC)细胞的增殖、侵袭、迁移及血管生成从而影响卵巢癌(OC)发展的作用机制。方法实时定量PCR检测29例OC灶及癌旁组织样本中TPT1-AS1和miR-324的表达;构建“TPT1-AS1过表达”与“miRNA324敲除”的两种OC细胞模型,并采用CCK-8、Transwell TM和划痕试验法检测细胞增殖、侵袭和迁移能力;Western blot法检测TWIST1、上皮钙黏蛋白(E-cadherin)、波形蛋白(Vimentin)、血管内皮生长因子A(VEGF-A)的蛋白表达;荧光原位杂交实验、RNA下拉实验验证TPT1-AS1与miR-324之间的相互作用;免疫组织化学染色法检测、Targetscan生物信息学分析验证miR-324的表达对上皮-间质转化(EMT)过程及血管生成有负调控作用。结果TPT1-AS1在OC组织中的表达水平显著高于癌旁组织,而miR-324的表达水平在OC组织中则显著低于癌旁组织。在TPT1-AS1过表达的人卵巢癌细胞株SKOV3细胞中,miR-324的表达水平明显下降,TPT1-AS1与miR-324呈显著负相关。实验还发现,TPT1-AS1与miR-324在OC细胞中共同表达,并且二者之间存在直接结合关系。下调miR-324显著促进了SKOV3细胞的增殖、侵袭和迁移能力。进一步研究发现miR-324与EMT关键转录因子TWIST13′-UTR端有结合位点,抑制miR-324表达可以上调TWIST1的转录水平,从而导致E-cadherin蛋白表达的下降和Vimentin蛋白表达的上升。此外,miR-324下调时,VEGF-A蛋白表达水平上升。结论本研究揭示了TPT1-AS1通过负调控miR-324/TWIST1轴促进EOC细胞增殖、侵袭、迁移以及血管生成,从而促进OC的发展,这些发现为OC的诊断和治疗提供了新的潜在靶点。 展开更多
关键词 卵巢癌(OC) 上皮-间质转化(EMT) twist1 miR-324 血管生成
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Retraction:Swainsonine inhibits invasion and the EMT process in esophageal carcinoma cells by targeting twist1
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作者 《Oncology Research》 2025年第5期1253-1253,共1页
The published article titled“Swainsonine inhibits invasion and the EMT process in esophageal carcinoma cells by targeting twist1”has been retracted from Oncology Research,Vol.26,No.8,2018,pp.1207–1213.
关键词 SWAINSONINE EMT twist targeting twist INVASION esophageal carcinoma esophageal carcinoma cells emt process
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lncRNA SNHG12通过miR-409-3p/TWIST1轴调节急性髓系白血病细胞的增殖、迁移和侵袭 被引量:1
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作者 赵海歌 王静 +1 位作者 肖梦瑶 崔雯萱 《医学研究与战创伤救治》 北大核心 2025年第2期135-142,共8页
目的探讨lncRNA SNHG12是否可通过miR-409-3p/TWIST1轴调节急性髓系白血病(AML)细胞的增殖、迁移和侵袭。方法用q RT-PCR检测47例急性髓系白血病患者和47例非血液系统肿瘤性疾病患者骨髓单个核细胞中SNHG12、miR-409-3p和TWIST1 mRNA的... 目的探讨lncRNA SNHG12是否可通过miR-409-3p/TWIST1轴调节急性髓系白血病(AML)细胞的增殖、迁移和侵袭。方法用q RT-PCR检测47例急性髓系白血病患者和47例非血液系统肿瘤性疾病患者骨髓单个核细胞中SNHG12、miR-409-3p和TWIST1 mRNA的表达水平;然后将HL-60细胞分为对照组、sh-NC组、sh-SNHG12组、sh-SNHG12+inhibitor NC组、sh-SNHG12+miR-409-3p inhibitor组、sh-SNHG12+oe-NC组、sh-SNHG12+oe-TWIST1组;用q RT-PCR检测各组细胞SNHG12、miR-409-3p和TWIST1 mRNA表达水平;CCK-8检测细胞增殖;Transwell实验检测细胞迁移和侵袭;流式细胞术检测细胞凋亡;Western blot检测细胞中TWIST1、CyclinD1、Ki67、Cleaved-caspase-3、MMP-9蛋白表达量。双荧光素酶报告基因实验检测miR-409-3p与SNHG12和TWIST1的靶向关系。结果AML患者骨髓单个核细胞和建株AML细胞中SNHG12和TWIST1 mRNA表达显著升高,miR-409-3p表达显著降低(P<0.05);下调SNHG12表达显著降低HL-60细胞中SNHG12和TWIST1 mRNA表达、A_(450)(24、48 h)值、细胞迁移和侵袭个数、TWIST1、CyclinD1、Ki67、MMP-9蛋白表达,提高凋亡率、miR-409-3p和Cleaved-caspase-3蛋白表达(P<0.05);下调miR-409-3p表达或上调TWIST1表达均可减弱下调SNHG12对HL-60细胞的抑制作用(P<0.05)。结论干扰SNHG12表达可提高miR-409-3p表达抑制TWIST1,进而抑制AML细胞增殖、迁移和侵袭。 展开更多
关键词 lncRNA SNHG12 miR-409-3p/twist1轴 急性髓系白血病 细胞
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USP8调控TWIST1对卵巢癌细胞上皮间质转化的影响
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作者 杨贺 蔡娱飞 +6 位作者 马奎丽 周影 李文会 鄢杰 陈雨 马溯阳 马哲 《海南医学》 2025年第6期761-766,共6页
目的探究USP8调控TWIST1对卵巢癌细胞上皮间质转化的影响。方法将卵巢癌OVCAR3细胞和SKOV3细胞均随机分为si NC实验组、si USP8实验组和si TWIST1实验组。采用细胞集落实验分析OVCAR3和SKOV3细胞的增殖能力;采用Transwell实验方法分析OV... 目的探究USP8调控TWIST1对卵巢癌细胞上皮间质转化的影响。方法将卵巢癌OVCAR3细胞和SKOV3细胞均随机分为si NC实验组、si USP8实验组和si TWIST1实验组。采用细胞集落实验分析OVCAR3和SKOV3细胞的增殖能力;采用Transwell实验方法分析OVCAR3和SKOV3细胞的侵袭能力;采用细胞划痕实验分析OVCAR3和SKOV3细胞的迁移能力;采用蛋白免疫印迹方法分析N-cadherin、Vimentin、USP8与TWIST1蛋白的表达。结果抑制USP8表达后,细胞集落实验显示,si USP8以及si TWIST1实验组的OVCAR3和SKOV3细胞增殖能力下降,差异均有统计学意义(P<0.05);Transwell实验显示,si USP8以及si TWIST1实验组的OVCAR3和SKOV3细胞侵袭数量下降,差异均有统计学意义(P<0.05);细胞划痕实验显示,si USP8以及si TWIST1实验组的OVCAR3和SKOV3细胞迁移率下降,差异均有统计学意义(P<0.05);蛋白免疫印迹实验结果显示,si USP8以及si TWIST1实验组的N-cadherin、Vimentin蛋白表达水平下降,si USP8实验组的USP8、TWIST1蛋白表达水平下降,差异均有统计学意义(P<0.05)。结论抑制USP8表达后,OVCAR3和SKOV3细胞的上皮间质转化过程受到抑制,该机制与USP8调节TWIST1密切相关。 展开更多
关键词 USP8 twist1 增殖 卵巢癌 侵袭 迁移 上皮间质转化 SIRNA
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炎症微环境下miR-210调控Twist1对牙周膜干细胞成骨分化的影响
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作者 郑兴 何家才 《实用口腔医学杂志》 北大核心 2025年第1期21-25,共5页
目的:研究炎症微环境下微小RNA(miR)-210调控Twist1对牙周膜干细胞(PDLSCs)成骨分化的影响。方法:培养PDLSCs,分为对照组、炎症组、miR-阴性对照(NC)组、炎症+miR-NC组、炎症+miR-210组、miR-NC+NC质粒组、炎症+miR-NC+NC质粒组、炎症+m... 目的:研究炎症微环境下微小RNA(miR)-210调控Twist1对牙周膜干细胞(PDLSCs)成骨分化的影响。方法:培养PDLSCs,分为对照组、炎症组、miR-阴性对照(NC)组、炎症+miR-NC组、炎症+miR-210组、miR-NC+NC质粒组、炎症+miR-NC+NC质粒组、炎症+miR-210+NC质粒组、炎症+miR-210+Twist1质粒组,各炎症组均采用10μg/L肿瘤坏死因子-α处理的方式建立炎症微环境,采用脂质体转染miR序列或质粒。处理24 h后检测miR-210和Twist1的表达水平;成骨诱导分化2周后检测茜素红染色的A590水平及Runt相关转录因子2(Runx2)、骨钙素(OCN)的表达水平。结果:炎症组的miR-210表达水平低于对照组,Twist1表达水平高于对照组(P<0.05);炎症+miR-NC组的miR-210表达水平及成骨诱导后的A590水平、Runx2及OCN表达水平均低于miR-NC组,Twist1表达水平高于miR-NC组(P<0.05);炎症+miR-210组的miR-210表达水平及成骨诱导后的A590水平、Runx2及OCN表达水平均高于炎症+miR-NC组,Twist1表达水平低于炎症+miR-NC组(P<0.05);miR-210组的Twist1表达水平及野生型Twist1报告基因的荧光值均低于miR-NC组(P<0.05);炎症+miR-210+Twist1质粒组的Twist1表达水平高于炎症+miR-210+NC质粒组,成骨诱导后的A590水平、Runx2及OCN表达水平均低于炎症+miR-210+NC质粒组(P<0.05)。结论:炎症微环境下miR-210表达降低,进而增加Twist1表达并抑制PDLSCs成骨分化。 展开更多
关键词 牙周炎 牙周膜干细胞 MIR-210 twist1 成骨分化
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一种基于TwIST稀疏正则化的冲击载荷识别方法
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作者 袁哲锋 缪炳荣 +3 位作者 张盈 金月皓 尹兆珂 胡天棋 《机械制造与自动化》 2025年第3期126-131,共6页
针对冲击载荷识别精度低的问题,提出一种基于稀疏正则化和两步迭代收缩阈值算法(TwIST)的冲击载荷识别方法。该方法采用稀疏正则化方法构建冲击载荷识别模型,使用TwIST算法迭代求解冲击载荷。通过铝合金梁冲击载荷识别试验对该方法进行... 针对冲击载荷识别精度低的问题,提出一种基于稀疏正则化和两步迭代收缩阈值算法(TwIST)的冲击载荷识别方法。该方法采用稀疏正则化方法构建冲击载荷识别模型,使用TwIST算法迭代求解冲击载荷。通过铝合金梁冲击载荷识别试验对该方法进行验证。结果表明:在单源、多源冲击载荷两种工况中,TwIST稀疏正则化方法能够准确识别冲击载荷,与传统的Tikhonov正则化方法相比,该方法的识别准确性、稳定性和抗噪性更优。 展开更多
关键词 冲击载荷识别 稀疏正则化 twist 逆问题
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基于Super-Twisting的自适应分数阶滑模控制PMSM调速系统
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作者 邹大林 刘曰涛 +3 位作者 于智勇 王福凯 温尚林 祝保财 《组合机床与自动化加工技术》 北大核心 2025年第9期103-107,共5页
针对PMSM在实际工作情况中面临复杂多变的工况、极易受到外界干扰且具有非线性的特点,常用的PI控制系统精度不高,难以满足现代工业电机控制要求,提出了一种新型自适应分数阶滑模控制(AFOSMC)方法。根据永磁同步电机的实时工作状态,采用... 针对PMSM在实际工作情况中面临复杂多变的工况、极易受到外界干扰且具有非线性的特点,常用的PI控制系统精度不高,难以满足现代工业电机控制要求,提出了一种新型自适应分数阶滑模控制(AFOSMC)方法。根据永磁同步电机的实时工作状态,采用自适应滑模控制实时地转变电机运行状态,相比于传统的PI控制更为灵活。同时结合一种Super-Twisting观测器,使控制系统有较强的鲁棒性。两者相结合取长补短,能更好地完成对PMSM的精确控制。通过实验验证,使用该控制系统超调量减小至3.9%,在突增负载时转速下降27 r/min,稳态调节时间为0.01 s,具有良好的运动性能和抗干扰性,且明显减小了传统滑模控制中的抖振现象。 展开更多
关键词 永磁同步电机 自适应控制 滑模控制 Super-twisting算法
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基于Super-Twisting滑模观测器的主动侧杆杆力控制研究
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作者 陈嘉鸿 张科平 王志胜 《机械与电子》 2025年第6期48-54,共7页
针对主动侧杆使用场景下电机受环境温度、磁场耦合等影响产生的综合扰动问题,设计了一种基于改进Super-Twisting滑模观测器无差拍电流预测控制方法,并对开关函数进行修改,加快扰动跟踪响应速度,抑制了因滑模面存在的不连续性而产生的高... 针对主动侧杆使用场景下电机受环境温度、磁场耦合等影响产生的综合扰动问题,设计了一种基于改进Super-Twisting滑模观测器无差拍电流预测控制方法,并对开关函数进行修改,加快扰动跟踪响应速度,抑制了因滑模面存在的不连续性而产生的高频抖振。此外,添加了自适应动态前馈参数调节,使主动侧杆系统在更大的电机参数摄动范围下能够稳定响应且保持良好的性能。同时,设计了一种前馈控制作为杆力控制器,改善杆力控制精度与跟踪性能。通过仿真实验可知,在电机模型参数产生较大摄动时,系统仍能稳定运行且有更小的电流波动,在杆力快速性与精度上有着更优秀的表现,证明了该算法的有效性。 展开更多
关键词 主动侧杆 无差拍电流预测控制 改进Super-twisting滑模观测器 自适应动态前馈
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miR-130a-5p靶向Twist1调控卵巢癌增殖与迁移
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作者 徐成博 惠豪斌 +4 位作者 李红希 吴蔚 朱昆维 王东旭 任碧琦 《黑龙江医药科学》 2025年第5期1-5,共5页
目的:明确miR-130a-5p对Twist1(扭曲螺旋转录因子1)的靶向调控作用及对卵巢癌转移的影响。方法:通过基因组测序将与卵巢癌有关的差异基因筛选出来,在临床标本中验证。本研究拟通过过表达miR-130a-5p,采用Transwell, CCK-8(细胞活力检测... 目的:明确miR-130a-5p对Twist1(扭曲螺旋转录因子1)的靶向调控作用及对卵巢癌转移的影响。方法:通过基因组测序将与卵巢癌有关的差异基因筛选出来,在临床标本中验证。本研究拟通过过表达miR-130a-5p,采用Transwell, CCK-8(细胞活力检测方法), Western blot等方法,明确miR-130a-5p对Twist的调控作用。结果:miR-130a-5p是通过生物信息学分析发现的miRNA。miR-130a-5p的表达与肿瘤组织有关,可能会对病人的预后造成影响。miR-130a-5p是前期研究发现的、显著高表达针对卵巢癌的miRNA。研究表明,在抑制卵巢癌细胞增殖和转移方面,miR-130a-5p发挥了一定作用。此外,机制研究表明,卵巢癌组织中Twist1表达显著上调,miR-130a-5p能抑制卵巢癌细胞EMT(上皮间质转化)及干细胞特性。结论:(1)miR-130a-5p是新近发现的在卵巢癌中发挥重要作用的miRNA。(2)miR-130a-5p通过Twist信号通路的调节来抑制卵巢癌的进展。 展开更多
关键词 卵巢癌 twist1 miR-130a-5p 增殖 迁移
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Birkhoff Orbits for Twist Homeomorphisms on the High-Dimensional Cylinder
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作者 ZHOU Tong 《Wuhan University Journal of Natural Sciences》 2025年第1期43-48,共6页
It is known that monotone recurrence relations can induce a class of twist homeomorphisms on the high-dimensional cylinder,which is an extension of the class of monotone twist maps on the annulus or two-dimensional cy... It is known that monotone recurrence relations can induce a class of twist homeomorphisms on the high-dimensional cylinder,which is an extension of the class of monotone twist maps on the annulus or two-dimensional cylinder.By constructing a bounded solution of the monotone recurrence relation,the main conclusion in this paper is acquired:The induced homeomorphism has Birkhoff orbits provided there is a compact forward-invariant set.Therefore,it generalizes Angenent's results in low-dimensional cases. 展开更多
关键词 monotone recurrence relation twist homeomorphism high-dimensional cylinder bounded action Birkhoff orbit
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Electrically tunable Г-Q interlayer excitons in twisted MoSe_(2)bilayers
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作者 Jinqiang Huang Zhiren Xiong +7 位作者 Jinkun He Xingguang Wu Kenji Watanabe Takashi Taniguchi Shen Lai Tongyao Zhang Zheng Vitto Han Siwen Zhao 《Journal of Materials Science & Technology》 2025年第4期70-75,共6页
Twist,the very degree of freedom in van der Waals heterostructures,offers a compelling avenue to manipulate and tailor their electrical and optical characteristics.In particular,moirépatterns in twisted homobilay... Twist,the very degree of freedom in van der Waals heterostructures,offers a compelling avenue to manipulate and tailor their electrical and optical characteristics.In particular,moirépatterns in twisted homobilayer transition metal dichalcogenides(TMDs)lead to zone folding and miniband formation in the resulting electronic bands,holding the promise to exhibit inter-layer excitonic optical phenomena.Although some experiments have shown the existence of twist-angle-dependent intra-and inter-layer excitons in twisted MoSe2 homobilayers,electrical control of the interlayer excitons in MoSe_(2) is relatively under-explored.Here,we show the signatures of the moiréeffect on intralayer and interlayer excitons in 2H-stacked twisted MoSe2 homobilayers.Doping-and electric field-dependent photoluminescence mea-surements at low temperatures give evidence of the momentum-direct K-K intralayer excitons,and the momentum-indirect Г-K and Г-Q interlayer excitons.Our results suggest that twisted MoSe_(2) homobilayers are an intriguing platform for engineering interlayer exciton states,which may shed light on future atomically thin optoelectronic applications. 展开更多
关键词 Interlayer excitons Intralayer excitons twisted bilayer TMDs Momentum indirect excitons
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Sub-Riemannian Limits,Connections with Torsion and the Gauss-Bonnet Theorem for Four Dimensional Twisted BCV Spaces
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作者 LI Hong-feng LIU Ke-feng WANG Yong 《Chinese Quarterly Journal of Mathematics》 2025年第2期111-134,共24页
In this paper,we compute sub-Riemannian limits of some important curvature variants associated with the connection with torsion for four dimensional twisted BCV spaces and derive a Gauss-Bonnet theorem for four dimens... In this paper,we compute sub-Riemannian limits of some important curvature variants associated with the connection with torsion for four dimensional twisted BCV spaces and derive a Gauss-Bonnet theorem for four dimensional twisted BCV spaces. 展开更多
关键词 Gauss-Bonnet theorem Sub-Riemannian limit twisted BCV spaces Orthogonal connections with torsion
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Higher-order topology in twisted multilayer systems:A review
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作者 Chunbo Hua Dong-Hui Xu 《Chinese Physics B》 2025年第3期2-10,共9页
In recent years,there has been a surge of interest in higher-order topological phases(HOTPs)across various disciplines within the field of physics.These unique phases are characterized by their ability to harbor topol... In recent years,there has been a surge of interest in higher-order topological phases(HOTPs)across various disciplines within the field of physics.These unique phases are characterized by their ability to harbor topological protected boundary states at lower-dimensional boundaries,a distinguishing feature that sets them apart from conventional topological phases and is attributed to the higher-order bulk-boundary correspondence.Two-dimensional(2D)twisted systems offer an optimal platform for investigating HOTPs,owing to their strong controllability and experimental feasibility.Here,we provide a comprehensive overview of the latest research advancements on HOTPs in 2D twisted multilayer systems.We will mainly review the HOTPs in electronic,magnonic,acoustic,photonic and mechanical twisted systems,and finally provide a perspective of this topic. 展开更多
关键词 higher-order topology twisted multilayer systems van der Waals materials corner states
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Thermal Torsion Effect of Twisted Polymer Actuators
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作者 Jiongjiong Hu Lei Liu +1 位作者 Hao Liu Dabiao Liu 《Acta Mechanica Solida Sinica》 2025年第2期320-330,共11页
Twisted polymer artificial muscles activated by thermal heating represent a new class of soft actuators capable of generating torsional actuation.The thermal torsion effect,characterized by the reversible untwisting o... Twisted polymer artificial muscles activated by thermal heating represent a new class of soft actuators capable of generating torsional actuation.The thermal torsion effect,characterized by the reversible untwisting of twisted fibers as temperature increases due to greater radial than axial thermal expansion,is crucial to the actuation performance of these artificial muscles.This study explores the thermal torsion effect of polymer muscles made of twisted Nylon 6 fibers in experimental and theoretical aspects,focusing on the interplay between material properties and temperature.It is revealed that the thermal torsion effect enhances the actuation performance of the twisted polymer actuator while the thermal softening effect diminishes it.A thermal-mechanical model incorporating both the thermal torsion effect and thermal softening effect is used to predict the recovered torque of the twisted polymer actuators.An optimal bias angle and operating temperature are identified to maximize the recovered torque.Analysis of strain and stress distributions in the cross-section of the twisted polymer fiber shows that the outer layers of the fiber predominantly contribute to the torsional actuation.This work aids in the precise control and structural optimization of the thermally-activated twisted polymer actuators. 展开更多
关键词 twisted fiber Artificial muscles Thermal torsion effect Thermal expansion coefficient Recovered torque
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Adaptive terminal sliding combined super twisting control design and flight tests for automatic carrier landing system
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作者 Zhuoer YAO Daochun LI +1 位作者 Zi KAN Jinwu XIANG 《Chinese Journal of Aeronautics》 2025年第4期437-449,共13页
Considering the challenges posed by external disturbances on carrier-based aircraft land-ing control,higher demands are required for the precision and convergence of the carrier landingcontrol system.First,this paper ... Considering the challenges posed by external disturbances on carrier-based aircraft land-ing control,higher demands are required for the precision and convergence of the carrier landingcontrol system.First,this paper proposes an Adaptive Terminal Sliding Combined Super TwistingControl(ATS-STC)method to address the issues of low precision,slow convergence,and poor dis-turbance rejection capability resulting from external disturbances,such as carrier air-wake and deckmotion.By introducing a nonlinear term into the sliding surface and employing an integralapproach,the proposed ATS-STC method can ensure finite-time convergence and mitigate the chat-tering problem.An adaptive law is also utilized to estimate the external disturbances,therebyenhancing the anti-disturbance performance.Then,the stability and convergence time analysis ofthe designed controller are conducted.Based on the proposed method,an Automatic Carrier Land-ing System(ACLS)is developed to perform the carrier landing control task.Furthermore,a multi-dimensional validation is carried out.For the numerical simulation test,the Terminal Sliding ModeControl(TSMC)method and Proportion Integration Differentiation(PID)method are introducedas comparison,the quantitative assessment results show that the tracking error of TSMC and PIDcan reach 1.5 times and 2 times that of the proposed method.Finally,the Hardware-in-the-Loop(HIL)test and real flight test are conducted.All the experimental results demonstrate that the pro-posed control method is more effective and precise. 展开更多
关键词 Terminal sliding mode control Super twisting control Automatic carrier landing system Numerical methods Hardware-in-the-loop test Flight test
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Tunable Electronic and Thermoelectric Performance in Twisted Bilayer Blue-Phosphorene Nanoribbon-Based Heterojunctions
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作者 Liang Zhang Shihua Tan +1 位作者 Xiaofang Peng Mengqiu Long 《Chinese Physics Letters》 2025年第6期155-162,共8页
In two-dimensional bilayer systems,twist-angle-dependent electronic and thermoelectric properties have garnered significant scientific interest in recent years.In this work,based on a combination of density functional... In two-dimensional bilayer systems,twist-angle-dependent electronic and thermoelectric properties have garnered significant scientific interest in recent years.In this work,based on a combination of density functional theory and nonequilibrium Green’s function method,we explore the electronic and thermoelectric properties in blue-phosphorene nanoribbon-based heterojunction(BPNRHJ)with and without blue-phosphorene nanoribbon(BPNR)stack.Our calculations find that the electronic conductance and power factor can be strongly enhanced by the BPNR stack,and their enhancements can be further observed with the twist between the layers.The main reason for this is the electronic hybridization between the layers can provide new transport channels,and the twist can modulate the strength of interlayer electronic hybridization,resulting in extremely violent fluctuations in electron transmission and hence an enhanced power factor.While the phonon thermal conductance exhibits very low dependence on the layer stack and twist.Combining these factors,our results reveal that the thermoelectric performance can be greatly modulated and enhanced in twist bilayer BPNRHJ:the figure of merit will be over 2.5 in 4-4-ZBPNR@ZGNR-AA-8.8∘at 500 K. 展开更多
关键词 tunable electronic properties thermoelectric performance twisted bilayer density functional theory electronic thermoelectric properties blue phosphorene nanoribbon heterojunction electronic conductance
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虚实奇境 Twist错觉博物馆
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作者 秋落(编译) Gilbert McCarragher(摄影) 《室内设计与装修》 2025年第12期146-147,共2页
位于伦敦市中心的Twist错觉博物馆旨在重新探索看待与感知事物的方式。访客的体验之旅始于牛津街的地面层。入口处即成为他们首个“接触”博物馆内容的场所:一个受牛津街历史及其昔日娱乐特色启发的预告空间,暗示着楼下将展现的奇妙世... 位于伦敦市中心的Twist错觉博物馆旨在重新探索看待与感知事物的方式。访客的体验之旅始于牛津街的地面层。入口处即成为他们首个“接触”博物馆内容的场所:一个受牛津街历史及其昔日娱乐特色启发的预告空间,暗示着楼下将展现的奇妙世界。红毯铺就的通道延伸至镜面天花板房间,这一充满错觉感的序章,预先揭示了后续旅程的盎然趣味。 展开更多
关键词 牛津街 伦敦市中心 twist错觉博物馆
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Quantum anomalous Hall effect in twisted bilayer graphene
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作者 Wen-Xiao Wang Yi-Wen Liu Lin He 《Chinese Physics B》 2025年第4期2-10,共9页
Recent advancements in two-dimensional van der Waals moir´e materials have unveiled the captivating landscape of moir´e physics.In twisted bilayer graphene(TBG)at‘magic angles’,strong electronic correlatio... Recent advancements in two-dimensional van der Waals moir´e materials have unveiled the captivating landscape of moir´e physics.In twisted bilayer graphene(TBG)at‘magic angles’,strong electronic correlations give rise to a diverse array of exotic physical phenomena,including correlated insulating states,superconductivity,magnetism,topological phases,and the quantum anomalous Hall(QAH)effect.Notably,the QAH effect demonstrates substantial promise for applications in electronic and quantum computing devices with low power consumption.This article focuses on the latest developments surrounding the QAH effect in magic-angle TBG.It provides a comprehensive analysis of magnetism and topology—two crucial factors in engineering the QAH effect within magic-angle TBG.Additionally,it offers a detailed overview of the experimental realization of the QAH effect in moir´e superlattices.Furthermore,this review highlights the underlying mechanisms driving these exotic phases in moir´e materials,contributing to a deeper understanding of strongly interacting quantum systems and facilitating the manipulation of new material properties to achieve novel quantum states. 展开更多
关键词 quantum anomalous Hall effect magic-angle twisted bilayer graphene moirésuperlattices
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