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可逆多分支的双模态自适应融合目标跟踪算法
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作者 耿礼智 周冬明 +2 位作者 王长城 刘宜松 孙逸秋 《激光与红外》 CAS CSCD 北大核心 2024年第11期1767-1776,共10页
由于可见光和红外图像具有很强的互补性,越来越多的关注集中在通过这两种模态的联合信息进行跟踪。然而,在现有的跟踪算法中,不能有效地学习两者的互补信息并挖掘模态特定特征,这限制了跟踪器的性能。因此,本文提出了一种可逆多分支的... 由于可见光和红外图像具有很强的互补性,越来越多的关注集中在通过这两种模态的联合信息进行跟踪。然而,在现有的跟踪算法中,不能有效地学习两者的互补信息并挖掘模态特定特征,这限制了跟踪器的性能。因此,本文提出了一种可逆多分支的双模态自适应融合跟踪网络。首先,设计了一个三分支结构网络,分别用于学习热红外、可见光以及它们的通用特征。这不仅充分利用了两种模态之间的共享信息,还保留了红外和可见光数据之间的差异特性以及丰富的细节信息。此外,还引入了一个模态特征交互模块,以自适应地挖掘模态之间的互补信息并滤除冗余信息。通过在多个公开数据集上进行大量实验证明了该跟踪器的有效性,尤其在面对尺度变化、镜头抖动、遮挡等环境时,表现出卓越的抗干扰能力。 展开更多
关键词 热红外目标跟踪 多分支 自适应融合 可逆结构
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阴离子主导的手性Cu(Ⅱ)配位聚合物:可逆的结构转换,圆二色谱和二次谐波响应(英文) 被引量:1
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作者 程林 刘琪 +1 位作者 杨晶华 章清松 《无机化学学报》 SCIE CAS CSCD 北大核心 2018年第6期1018-1027,共10页
用手性的V形双齿配体N,N′-((1R,2R)-1,2-二取代环己二胺)双(N-苯甲酸(3-吡啶亚甲基)酰胺(1R,2R)-3-bcpb)和不同的Cu(Ⅱ)盐反应,组装成2个新的手性Cu(Ⅱ)配位聚合物{[Cu((1R,2R)-3-bcpb)]Cl_2}_n(1)和{[Cu((1R,2R)-3-bcpb)_2](ClO_4)2&#... 用手性的V形双齿配体N,N′-((1R,2R)-1,2-二取代环己二胺)双(N-苯甲酸(3-吡啶亚甲基)酰胺(1R,2R)-3-bcpb)和不同的Cu(Ⅱ)盐反应,组装成2个新的手性Cu(Ⅱ)配位聚合物{[Cu((1R,2R)-3-bcpb)]Cl_2}_n(1)和{[Cu((1R,2R)-3-bcpb)_2](ClO_4)2·2H_2O·2CH_3OH}_n(2)。其中1是一维链状结构,2具有二维(4,4)网络拓扑。溶剂热条件下,在甲醇溶剂体系中,通过引入AgClO_4,1能转换成2,同时通过加入NaCl,2也能转换成1。圆二色谱和二次谐波响应测试验证了它们具有结构上的手性。 展开更多
关键词 手性配位聚合物 可逆结构转换 手性-1 2-环己二胺 阴离子主导
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Sn-Bi合金熔体可逆液-液结构转变的研究 被引量:6
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作者 胡成明 李先芬 +3 位作者 祖方遒 毛丽娜 刘明全 刘永驰 《原子与分子物理学报》 CAS CSCD 北大核心 2008年第4期1003-1007,共5页
本文采用直流四电极电阻法研究了Sn-Bi系合金熔体在连续几轮的升降温过程中电阻率随温度的变化规律.结果表明,Sn-Bi合金熔体在连续几轮的升降温过程都出现了电阻率随温度的异常变化.由于电阻率是结构敏感物理参数之一,电阻率随温度的异... 本文采用直流四电极电阻法研究了Sn-Bi系合金熔体在连续几轮的升降温过程中电阻率随温度的变化规律.结果表明,Sn-Bi合金熔体在连续几轮的升降温过程都出现了电阻率随温度的异常变化.由于电阻率是结构敏感物理参数之一,电阻率随温度的异常变化间接表明合金熔体发生了温度诱导的液态结构转变,而且转变具有一定的可逆性.对比纯锡和纯铋的电阻率实验结果,可以认为结构转变的可逆性主要与合金中Sn的有关. 展开更多
关键词 SN-BI合金 电阻率 可逆液态结构转变
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可逆弱群缠绕结构的例子与群余环(英文)
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作者 方小利 《南京大学学报(数学半年刊)》 CAS 2010年第1期57-74,共18页
作为弱缠绕结构的自然推广,我们引进了(广义)弱群缠绕结构的概念,并通过弱Hopf群余代数构造了一些例子.进一步,通过弱Hopf群余代数也构造了可逆弱群缠绕结构的例子.在这篇文章中,我们还用群余环解释这些概念的重要性.
关键词 群余环 弱群缠绕结构 可逆弱群缠绕结构
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基于动态共价键的液晶弹性体可逆三维结构加工方法研究进展 被引量:1
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作者 张宇白 吉岩 《液晶与显示》 CAS CSCD 北大核心 2022年第2期199-216,共18页
液晶弹性体是一类在外界刺激(如热、光、电、磁等)下能够产生宏观可逆形变的智能材料。液晶弹性体必须经过取向后才能够展现宏观可逆形变性能。动态共价键在一定的条件下可以发生可逆断裂与再生成,能够改变传统共价交联网络的拓扑结构,... 液晶弹性体是一类在外界刺激(如热、光、电、磁等)下能够产生宏观可逆形变的智能材料。液晶弹性体必须经过取向后才能够展现宏观可逆形变性能。动态共价键在一定的条件下可以发生可逆断裂与再生成,能够改变传统共价交联网络的拓扑结构,因此可被用于液晶弹性体的取向中。液晶弹性体可构筑具有一定形状、且在外界刺激下能够产生可逆形变的智能三维结构,在生物医药、组织工程、航空航天以及柔性机器人等多种领域具有广阔的应用前景。基于动态共价键取向法,对液晶弹性体进行三维空间取向或对液晶弹性体进行组装,有助于提高液晶弹性体可逆三维结构的复杂性,并丰富其形变模式。本文对基于动态共价键的液晶弹性体可逆三维结构的加工方法进行综述,并对该领域的挑战和机遇进行分析。 展开更多
关键词 液晶弹性体 动态共价键 可逆三维结构 取向 组装
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一种新型压裂液 被引量:49
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作者 罗平亚 郭拥军 刘通义 《石油与天然气地质》 EI CAS CSCD 北大核心 2007年第4期511-515,共5页
在"可逆结构溶液"新型压裂液概念的指导下,研制出一种新型压裂液增稠剂及其压裂液体系。试验研究表明:该体系G′恒大于G,″是典型的粘弹结构溶液;粘度不低于30 mPa.s(170 s-1)的体系携砂能力即可满足施工要求;温度为150℃,增... 在"可逆结构溶液"新型压裂液概念的指导下,研制出一种新型压裂液增稠剂及其压裂液体系。试验研究表明:该体系G′恒大于G,″是典型的粘弹结构溶液;粘度不低于30 mPa.s(170 s-1)的体系携砂能力即可满足施工要求;温度为150℃,增稠剂加量仅为0.8 wt%时,体系粘度既达到了30 mPa.s(170 s-1)以上,且对剪切时间不敏感;破胶液"清洁",对支撑剂导流能力保持在90%以上,岩心渗透率伤害低于10%。中原油田5口井(濮65-9、文99-20、卫10-40、卫侧214、卫355-4井)的应用表明,该新型压裂液施工简单,与常规压裂液相比组分少、配制简单,携砂性能良好,摩阻仅为清水的22%,使用温度已达到120℃,对地层的伤害低,取得了比常规压裂液更好的增产效果。 展开更多
关键词 可逆结构溶液 压裂液 清洁压裂液 增稠剂
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超分子压裂液的研究及现场应用 被引量:3
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作者 方梦莉 高婷 徐毓珠 《江汉石油职工大学学报》 2014年第3期18-20,共3页
超分子压裂液体系属于可逆交联的多元结构型聚合物,有别于胍胶和其他合成聚合物,此结构可随剪切速率、盐度和温度等条件变化而可逆变化。通过对该压裂液体系的耐剪切性能、流变特征、携砂,破胶等室内的评价分析,现场应用表明:该新型压... 超分子压裂液体系属于可逆交联的多元结构型聚合物,有别于胍胶和其他合成聚合物,此结构可随剪切速率、盐度和温度等条件变化而可逆变化。通过对该压裂液体系的耐剪切性能、流变特征、携砂,破胶等室内的评价分析,现场应用表明:该新型压裂液体系与常规压裂液相比具有组分少、施工配液简单、携砂优良、破胶彻底,对地层的伤害低,易于返排等优点,在改造低渗透油气藏及非常规油气藏中具有明显优势。 展开更多
关键词 超分子压裂液 可逆结构 低伤害 储层改造
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Study on the Reversible DC-DC Converter as Interface between Low and Medium Voltage DC Networks
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作者 Stephan Kenzelmann Carlo Arrioja Alfred Rufer 《Journal of Energy and Power Engineering》 2012年第8期1284-1291,共8页
This paper introduces an isolated reversible DC-DC converter with a particular topology, which benefits from both the NPC (neutral point clamped) structure and the series-parallel connection of converters. The key p... This paper introduces an isolated reversible DC-DC converter with a particular topology, which benefits from both the NPC (neutral point clamped) structure and the series-parallel connection of converters. The key property of the proposed topology is the output voltage elevation above the blocking capabilities of each switch, without taking to a delicate synchronization of series-connected semiconductors. The converter is composed by two identical cells, each containing a full bridge, a medium frequency transformer and an NPC converter, connected in parallel at the input and in series at the output. The operation principle of each cell, into which a trapezoidal modulation was implemented, is similar to a DAB (dual active bridge). A new model improves the dynamic performance of the controller. Simulation and experimental results verify the proposed topology, its control and start-up strategy. 展开更多
关键词 DC-DC converter multilevel converter DC transformer medium voltage medium frequency transformer.
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Non-Linear Dependence in Oil Price Behavior
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作者 Semei Coronado Ramirez Leonardo Gatica Arreola Mauricio Ramirez Grajeda 《Journal of Mathematics and System Science》 2012年第2期110-118,共9页
In this paper, the authors analyze the adequacy of GARCH-type models to analyze oil price behavior by applying two types of non-parametric tests, the Hinich portmanteau test for non-linear dependence and a frequency-d... In this paper, the authors analyze the adequacy of GARCH-type models to analyze oil price behavior by applying two types of non-parametric tests, the Hinich portmanteau test for non-linear dependence and a frequency-dominant test of time reversibility, the reverse test based on the bispectrum, to explore the high-order spectrum properties of the Mexican oil price series. The results suggest strong evidence of a non-linear structure and time irreversibility. Therefore, it does not comply with the i.i.d (independent and identically distributed) property. The non-linear dependence, however, is not consistent throughout the sample period, as indicated by a windowed test, suggesting episodic nonlinear dependence. The results imply that GARCH models cannot capture the series structure. 展开更多
关键词 Bispcctrum time reversibility NONLINEARITY asymmetry oil price.
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醇溶剂交换对聚合物/黏土纳米复合水凝胶的性能改进及结构表征 被引量:1
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作者 任怀银 朱美芳 原口和敏 《高分子学报》 SCIE CAS CSCD 北大核心 2012年第7期689-693,共5页
采用原位自由基聚合,制备了聚N,N-二甲基丙烯酰胺(PDMAA)/黏土(clay)纳米复合水凝胶(D-NCgel),黏土在体系结构中充当多官能团交联点的作用.考察了D-NC gel中溶剂水被交换为醇溶剂时,凝胶结构稳定性,溶胀特性,以及机械性能的变化.D-NC ge... 采用原位自由基聚合,制备了聚N,N-二甲基丙烯酰胺(PDMAA)/黏土(clay)纳米复合水凝胶(D-NCgel),黏土在体系结构中充当多官能团交联点的作用.考察了D-NC gel中溶剂水被交换为醇溶剂时,凝胶结构稳定性,溶胀特性,以及机械性能的变化.D-NC gel在醇溶剂中仍能保持完整的三维网络结构,体系没有瓦解.而且,D-NC gel在醇溶剂中表现出依赖于醇溶剂种类的溶剂交换和溶胀行为.在甲醇中,凝胶溶胀度呈现单调增长,但是在其它醇溶剂,如乙醇、1-丙醇或1-丁醇中,凝胶表现出先收缩后溶胀的特殊溶胀行为.通过在醇溶剂中先溶胀后干燥的方法,制备具有优异机械性能的醇溶剂纳米复合凝胶.与D-NC5 gel相比,D-NC5甲醇凝胶其拉伸力学强度提高了67%(从155 kPa增加到259 kPa),拉伸模量提高了49%(从7.5 kPa增加到11.2kPa).基于凝胶在醇水溶剂中结构可逆性讨论的基础上,探讨了醇溶剂对D-NC水凝胶的改性机理. 展开更多
关键词 纳米复合水凝胶 黏土 醇溶剂 溶胀行为 机械性能 结构可逆
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单轴柔性铰链设计方法研究 被引量:62
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作者 李玉和 李庆祥 +1 位作者 陈璐云 白立芬 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2002年第2期172-174,共3页
针对微机电系统中常用单轴柔性铰链机构原始理论设计的复杂性 ,提出了简洁而准确的单轴柔性铰链设计计算方法。从基础理论出发推导出了柔性铰链刚度及转角设计公式 ,分析了柔性铰链设计中结构参数与性能的关系。通过一种压电驱动微动工... 针对微机电系统中常用单轴柔性铰链机构原始理论设计的复杂性 ,提出了简洁而准确的单轴柔性铰链设计计算方法。从基础理论出发推导出了柔性铰链刚度及转角设计公式 ,分析了柔性铰链设计中结构参数与性能的关系。通过一种压电驱动微动工作台设计实例分析了单轴柔性铰链机构在微机电系统中的应用。实践证明了该方法的简便。 展开更多
关键词 柔性铰链 微机电系统 计算机辅助设计 刚度 转角 机械传动 可逆弹性支撑结构
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Boosting reaction kinetics and reversibility in Mott-Schottky VS/MoS heterojunctions for enhanced lithium storage 被引量:4
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作者 Yuru Dong Yu Liu +3 位作者 Yanjie Hu Kun Ma Hao Jiang Chunzhong Li 《Science Bulletin》 SCIE EI CAS CSCD 2020年第17期1470-1478,M0004,共10页
Heterostructures have lately been recognized as a viable implement to achieve high-energy Li-ion batteries(LIBs) because the as-formed built-in electric field can greatly accelerate the charge transfer kinetics. Herei... Heterostructures have lately been recognized as a viable implement to achieve high-energy Li-ion batteries(LIBs) because the as-formed built-in electric field can greatly accelerate the charge transfer kinetics. Herein, we have constructed the Mott-Schottky heterostructured VS2/MoS2 hybrids with tailorable 1T/2H phase based on their matchable formation energy, which are made of metallic and few-layered VS2 vertically grown on MoS2 surface. The density functional theory(DFT) calculations unveil that such heterojunctions drive the rearrangement of energy band with a facilitated reaction kinetics and enhance the Li adsorption energy more than twice compared to the MoS2 surface. Furthermore, the VS2 catalytically expedites the Li–S bond fracture and meantime the enriched Mo6+ enables the sulfur anchoring toward the oriented reaction with Li+to form Li2S, synergistically enhancing the reversibility of electrochemical redox. Consequently, the as-obtained VS2/MoS2 hybrids deliver a very large specific capacity of 1273 m Ah g^-1 at 0.1 A g^-1 with 61% retention even at 5 A g^-1. It can also stabilize 100 cycles at 0.5 A g^-1 and 500 cycles at 1 A g^-1. The findings provide in-depth insights into engineering heterojunctions towards the enhancement of reaction kinetics and reversibility for LIBs. 展开更多
关键词 HETEROSTRUCTURE VS2/MoS2 Interface effect High-energy density Li-ion batteries
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On Inherent Irreversibility in a Reactive Hydromagnetic Channel Flow 被引量:1
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作者 O.D.Makinde O.Anwar Bég 《Journal of Thermal Science》 SCIE EI CAS CSCD 2010年第1期72-79,共8页
This study is devoted to investigate the inherent irreversibility and thermal stability in a reactive electrically conducting fluid flowing steadily through a channel with isothermal walls under the influence of a tra... This study is devoted to investigate the inherent irreversibility and thermal stability in a reactive electrically conducting fluid flowing steadily through a channel with isothermal walls under the influence of a transversely imposed magnetic field.Using a perturbation method coupled with a special type of Hermite-Pade' approximation technique,the simplified governing non-linear equation is solved and the important properties of overall flow structure including velocity field,temperature field and thermal criticality conditions are derived which essentially expedite to obtain expressions for volumetric entropy generation numbers,irreversibility distribution ratio and the Bejan number in the flow field. 展开更多
关键词 Hydromagnetic channel flow Entropy analysis Thermal criticality Arrhenius kinetics Hermite-Pade approximants
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Reversible phase transition of the 1:1 complex between 18-crown-6 and n-propylammonium triiodide
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作者 GE JiaZhen 《Science China Chemistry》 SCIE EI CAS 2012年第2期208-213,共6页
Solid-state structure of the crystalline 1:1 complex [C3H10N(18-crown-6)]+[I3] (1) between 18-crown-6 and n-propylammonium triiodide has been determined at 293 and 93 K, respectively, showing a change from monoc... Solid-state structure of the crystalline 1:1 complex [C3H10N(18-crown-6)]+[I3] (1) between 18-crown-6 and n-propylammonium triiodide has been determined at 293 and 93 K, respectively, showing a change from monoclinic P21/m to monoclinic P21/a. Crystal structural analysis shows that in addition to van der Waals' forces, conventional N-H..-O hydrogen bonds are the key interactions. Measurements of unit cell parameters versus temperature show that the values of one of the three axes and the crystal volume change abruptly and remarkably at 220 K, indicating a first-order phase transition. The lack of the mirror plane in the low temperature structure is the most important differences between the two structural forms. Dif- ferential scanning calorimetry (DSC) measurement confirms that I undergoes a reversible phase transition at about 220 K with a thermal hysteresis of 3.5 K. The relatively large latent heat makes 1 a good candidate for phase change materials. The phase transition is accompanied by an anomaly of dielectric constant during heating and cooling process near the phase transition temperature. 展开更多
关键词 phase transition dielectric constant phase change material crown ether crystal structure
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Complex micelles with the bioactive function of reversible oxygen transfer
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作者 Liangliang Shen Lizhi Zhao +4 位作者 Rui Qu Fan Huang Hongjun Gao Yingli An Linqi Shi 《Nano Research》 SCIE EI CAS CSCD 2015年第2期491-501,共11页
A complex micelle as a hemoglobin functional model with the biaoactive function of reversible oxygen transfer has been constructed through the hierarchical assembly of the diblock copolymer poly(ethylene glycol)-blo... A complex micelle as a hemoglobin functional model with the biaoactive function of reversible oxygen transfer has been constructed through the hierarchical assembly of the diblock copolymer poly(ethylene glycol)-block- poly(4-vinylpyridine-co-N-heptyl-4-vinylpyridine) (PEG-b-P(4VP-co-4VPHep)), tetrakis(4-sulfonatophenyl)porphinato iron(II) (Fe(II)TPPS) and β-cyclodextrin (β-CD). The μ-oxo dimer of Fe(II)TPPS was successfully inhibited because the Fe(II)TPPS was included into the cavities of β-CDs through host-guest interaction. Fe(II)TPPS coordinated with pyridine groups functions as the active site to reversibly bind dioxygen. In adition, the host-guest inclusion (β-CD/Fe(II)TPPS) was encapsulated in the hydrophobic core of the complex micelle and tightly fixed by P4VP chains. The hydrophilic PEG blocks stretched in aqueous solution to constitute the shells which stabilize the structure of the complex micelle as well as endow the complex micelle with sufficient blood circulation time. Dioxygen can be bound to the Fe(II)TPPS located in the confined space and excellent reversibility of the binding-release process of dioxygen can be achieved. The quaternary amine N-heptyl-4-vinylpyridine can coerce abundant S2O4^2- ions into the core of the complex micelle to facilitate the self-reduction process. Dioxygen adducts (Fe(II)TPPS(O2)) were effectively protected by the double hydrophobic barriers constructed by the cavity of the cyclodextrin and the core of the complex micelle which enhances the ability to resist nucleophilic molecules. Therefore, the rationally designed amphiphilic structure can work as a promising artificial O2 carrier. Potentially, the complex micelle can be expected to improve the treatment of diseases linked with hypoxia. 展开更多
关键词 ionic block copolymer bioactive self-assembly METALLOPORPHYRIN reversibledioxygen-binding proton sponge effect
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