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跨域联合学习与共享子空间度量的车辆重识别
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作者 汪琦 雪心远 +3 位作者 闵卫东 汪晟 盖迪 韩清 《中国图象图形学报》 CSCD 北大核心 2024年第5期1364-1380,共17页
目的 现有的跨域重识别任务普遍存在源域与目标域之间的域偏差大和聚类质量差的问题,同时跨域模型过度关注在目标域上的泛化能力将导致对源域知识的永久性遗忘。为了克服以上挑战,提出了一个基于跨域联合学习与共享子空间度量的车辆重... 目的 现有的跨域重识别任务普遍存在源域与目标域之间的域偏差大和聚类质量差的问题,同时跨域模型过度关注在目标域上的泛化能力将导致对源域知识的永久性遗忘。为了克服以上挑战,提出了一个基于跨域联合学习与共享子空间度量的车辆重识别方法。方法 在跨域联合学习中设计了一种交叉置信软聚类来建立源域与目标域之间的域间相关性,并利用软聚类结果产生的监督信息来保留旧知识与泛化新知识。提出了一种显著性感知注意力机制来获取车辆的显著性特征,将原始特征与显著性特征映射到一个共享子空间中并通过它们各自全局与局部之间的杰卡德距离来获取共享度量因子,根据共享度量因子来平滑全局与局部的伪标签,进而促使模型能够学习到更具鉴别力的特征。结果 在3个公共车辆重识别数据集VeRi-776(vehicle re-identification-776 dataset)、VehicleID(largescale vehicle re-identification dataset)和VeRi-Wild(vehicle re-identification dataset in the wild)上与较新方法进行实验对比,以首位命中率(rank-1 accuracy,Rank-1)和平均精度均值(mean average precision,mAP)作为性能评价指标,本文方法在VeRi-776→VeRi-Wild,VeRi-Wild→VeRi-776,VeRi-776→VehicleID,VehicleID→VeRi-776的跨域任务中,分别在目标域中取得了42.40%,41.70%,56.40%,61.90%的Rank-1准确率以及22.50%,23.10%,41.50%,49.10%的mAP准确率。在积累源域的旧知识表现中分别取得了84.60%,84.00%,77.10%,67.00%的Rank-1准确率以及55.80%,44.80%,46.50%,30.70%的mAP准确率。结论 相较于无监督域自适应和无监督混合域方法,本文方法能够在积累跨域知识的同时有效缓解域偏差大的问题,进而提升车辆重识别的性能。 展开更多
关键词 车辆重识别 跨域联合学习(CJL) 交叉置信软聚类 共享空间度量(SSM) 显著性感知注意力机制 伪标签平滑
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闭映射和稳定集拓扑(英文)
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作者 陈怀鹏 王博森 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第4期94-100,共7页
首次引入稳定集拓扑空间的概念,研究了稳定集拓扑空间并得到了稳定集拓扑空间的一些命题.然后利用这些命题,得到了闭映射的一个新的特征.利用稳定集拓扑空间的技巧,证明了关于子量量空间完全像的一个定理.
关键词 闭映射 度量空间 子度量空间 μ-空间 稳定集拓扑空间
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Investigation of the Ion-Exchange Behavior of Zeolite Y in the Presence of Resin 被引量:2
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作者 Zhang Yi Zheng Jinyu +3 位作者 Liu Zhongqing Gao Xiuzhi Luo Yibin Zong Baoning 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第2期50-56,共7页
Ion-exchange process of zeolite Y using ammonium-type resin as an exchange reagent was successfully carried out. The effect of temperature, space velocity and ion concentration on the breakthrough curves was carefully... Ion-exchange process of zeolite Y using ammonium-type resin as an exchange reagent was successfully carried out. The effect of temperature, space velocity and ion concentration on the breakthrough curves was carefully investigated. At the first exchange section, the maximum proportion of qualified zeolites(QR) was obtained at a temperature of 70 ℃, a weight hourly space velocity of 0.61 h-1, and an ion concentration of 197 mg/L. The minimum length of mass-transfer zone(MTZ) of the resin bed was achieved at a temperature of 70 ℃, a space velocity of 0.61 h-1, and an ion concentration of 423 mg/L. At the second exchange section, the length of MTZ of the resin bed was significantly increased, and the exchange of Na+ ions contained in zeolite Y was more difficult than that achieved at the first exchange section. In both the first and the second exchange sections, the zeolite Y subjected to ion exchange with the resin maintained the similar physical and chemical properties as compared to those exchanged by the conventional approaches, but the zeolite Y, which was obtained after ion exchange, contained a significantly lower content of Na2 O. 展开更多
关键词 zeolite Y RESIN ion-exchange
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Disentanglement of Two Qubits Coupled to an XY Spin Chain at Finite Temperature
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作者 NIE Jing WANG Lin-Cheng YI Xue-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期815-819,共5页
The disentanglement evolution of bipartite spin-1/2 system coupled to a common surrounding XY chain in transverse fields at nonzero temperature is studied in this letter. The dynamical process of the entanglement is n... The disentanglement evolution of bipartite spin-1/2 system coupled to a common surrounding XY chain in transverse fields at nonzero temperature is studied in this letter. The dynamical process of the entanglement is numerically and analytically investigated. We find that thermal effects can enhance disentanglement if the entangled initial state of the central spins does not in the decoherence free space. The critical phenomenon of quantum phase transitions reflected in the disentanglement can be washed out by the thermal effect eventually. 展开更多
关键词 DISENTANGLEMENT quantum phase transition XY spin chain
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PT Symmetric Quantum Models Living in an Auxiliary Pontryagin Space
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作者 Miloslav Znojil 《Journal of Mathematics and System Science》 2012年第2期102-109,共8页
In the traditional theoretical descriptions of microscopic physical systems (typically, atoms and molecules) people strongly relied upon analogies between the classical mechanics and quantum theory. Naturally, such ... In the traditional theoretical descriptions of microscopic physical systems (typically, atoms and molecules) people strongly relied upon analogies between the classical mechanics and quantum theory. Naturally, such a methodical framework proved limited as it excluded, up to the recent past, multiple, less intuitively accessible phenomenological models from the serious consideration. For this reason, the classical-quantum parallels were steadily weakened, preserving still the basic and robust abstract version of the key Copenhagen-school concept of treating the states of microscopic systems as elements of a suitable linear Hilbert space. Less than 20 years ago, finally, powerful innovations emerged on mathematical side. Various less standard representations of the Hilbert space entered the game. Pars pro toto, one might recall the Dyson's representation of the so-called interacting boson model in nuclear physics, or the steady increase of popularity of certain apparently non-Hermitian interactions in field theory. In the first half of the author's present paper the recent heuristic progress as well as phenomenologieal success of the similar use of non-Hermitian Ham iltonians will be reviewed, being characterized by their self-adjoint form in an auxiliary Krein space K. In the second half of the author's text a further extension of the scope of such a mathematically innovative approach to the physical quantum theory is proposed. The author's key idea lies in the recommendation of the use of the more general versions of the indefinite metrics in the space of states (note that in the Krein-space case the corresponding indefinite metric P is mostly treated as operator of parity). Thus, the author proposes that the operators P should be admitted to represent, in general, the indefinite metric in a Pontryagin space. A constructive version of such a generalized quantization strategy is outlined and found feasible. 展开更多
关键词 Quantum mechanics Hermitizations of observables auxiliary Krein and Pontryagin spaces Jacobi-matrix Hamiltonians Dieudonne equation.
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Full-Scale Measurement and Numerical Analysis of Liquefied Petroleum Gas Water Heaters with Ventilation Factors in Balcony
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作者 Chen-Wei Chiu Chiun-Hsun Chen +1 位作者 Chun-Wan Chen Yueh-Jen Chen 《Journal of Civil Engineering and Architecture》 2015年第11期1341-1353,共13页
This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtig... This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space. 展开更多
关键词 Water heater carbon monoxide FDS POISON LPG (liquefied petroleum gas).
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Grassmann流形上半监督特征映射算法及其视频目标识别 被引量:2
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作者 李淑芳 曾宪华 冯萧 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2014年第2期265-270,共6页
将视频集看成Grassmann流形上的子空间集合,结合半监督的拉普拉斯特征映射算法,即基于子空间相似性度量和具有标记子空间的类别信息,将视频集非线性地映射到低维欧氏空间,提出Grassmann流形上半监督特征映射算法对视频目标进行识别,该... 将视频集看成Grassmann流形上的子空间集合,结合半监督的拉普拉斯特征映射算法,即基于子空间相似性度量和具有标记子空间的类别信息,将视频集非线性地映射到低维欧氏空间,提出Grassmann流形上半监督特征映射算法对视频目标进行识别,该算法分别在步态视频数据库、人手姿势视频数据库和物体姿势视频数据库上进行了目标识别实验,并和典型的基于子空间相似性的分类算法的识别结果进行对比,证明该算法具有较好的性能。 展开更多
关键词 GRASSMANN流形 空间距离度量 半监督特征映射视 视频目标识别
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Quantum hyperentanglement and its applications in quantum information processing 被引量:13
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作者 Fu-Guo Deng Bao-Cang Ren Xi-Han Li 《Science Bulletin》 SCIE EI CAS CSCD 2017年第1期46-68,共23页
Hyperentanglement is a promising resource in quantum information processing with its high capacity character, defined as the entanglement in multiple degrees of freedom(DOFs) of a quantum system, such as polarization,... Hyperentanglement is a promising resource in quantum information processing with its high capacity character, defined as the entanglement in multiple degrees of freedom(DOFs) of a quantum system, such as polarization, spatial-mode, orbit-angular-momentum, time-bin and frequency DOFs of photons.Recently, hyperentanglement attracts much attention as all the multiple DOFs can be used to carry information in quantum information processing fully. In this review, we present an overview of the progress achieved so far in the field of hyperentanglement in photon systems and some of its important applications in quantum information processing, including hyperentanglement generation, complete hyperentangled-Bell-state analysis, hyperentanglement concentration, and hyperentanglement purification for high-capacity long-distance quantum communication. Also, a scheme for hyper-controlled-not gate is introduced for hyperparallel photonic quantum computation, which can perform two controlled-not gate operations on both the polarization and spatial-mode DOFs and depress the resources consumed and the photonic dissipation. 展开更多
关键词 Quantum hyperentanglement High-capacity quantum communication Concentration and purification Hyperparallel photonic quantumcomputation Quantum information processing
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METRIC GENERALIZED INVERSE OF LINEAR OPERATOR IN BANACH SPACE 被引量:29
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作者 WANGHUI WANGYUWEN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2003年第4期509-520,共12页
The Moore-Penrose metric generalized inverse T+ of linear operator T in Banach space is systematically investigated in this paper. Unlike the case in Hilbert space, even T is a linear operator in Banach Space, the Moo... The Moore-Penrose metric generalized inverse T+ of linear operator T in Banach space is systematically investigated in this paper. Unlike the case in Hilbert space, even T is a linear operator in Banach Space, the Moore-Penrose metric generalized inverse T+ is usually homogeneous and nonlinear in general. By means of the methods of geometry of Banach Space, the necessary and sufficient conditions for existence, continuitv, linearity and minimum property of the Moore-Penrose metric generalized inverse T+ will be given, and some properties of T+ will be investigated in this paper. 展开更多
关键词 Banach space Metric generalized inverse Generalized orthogonal decomposition Homogeneous operator
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Coarse Embedding into Uniformly Convex Banach Spaces
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作者 Qinggang REN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第5期733-742,共10页
In this paper, the author studies the coarse embedding into uniformly convex Banach spaces. The author proves that the property of coarse embedding into Banach spaces can be preserved under taking the union of the met... In this paper, the author studies the coarse embedding into uniformly convex Banach spaces. The author proves that the property of coarse embedding into Banach spaces can be preserved under taking the union of the metric spaces under certain condi- tions. As an application, for a group G strongly relatively hyperbolic to a subgroup H, the author proves that B(n) = {g ∈ G/ │g│suЭe≤ n} admits a coarse embedding into a uniformly convex Banach space if H does. 展开更多
关键词 Coarse embedding Uniformly convex Banach spaces Relative hyper-bolic groups
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Remarks on the Operator Norm Localization Property
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作者 Xianjin WANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2011年第4期593-604,共12页
The author studies the metric spaces with operator norm localization property. It is proved that the operator norm localization property is coarsely invariant and is preserved under certain infinite union. In the case... The author studies the metric spaces with operator norm localization property. It is proved that the operator norm localization property is coarsely invariant and is preserved under certain infinite union. In the case of finitely generated groups, the operator norm localization property is also preserved under the direct limits. 展开更多
关键词 Metric space Asymptotic dimension Operator norm localization Coarse invariance Roe algebra
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Fisher Information and Complexity Measure of Generalized Morse Potential Model
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作者 C.A. Onate J.O.A. Idiodi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第9期275-279,共5页
The spreading of the quantum-mechanical probability distribution density of the three-dimensional system is quantitatively determined by means of the local information-theoretic quantity of the Shannon information and... The spreading of the quantum-mechanical probability distribution density of the three-dimensional system is quantitatively determined by means of the local information-theoretic quantity of the Shannon information and information energy in both position and momentum spaces. The complexity measure which is equivalent to Cramer–Rao uncertainty product is determined. We have obtained the information content stored, the concentration of quantum system and complexity measure numerically for n = 0, 1, 2 and 3 respectively. 展开更多
关键词 fisher information Shannon entropy complexity measures
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Room-Temperature Steady-State Entanglement in a Four-Mode Optomechanical System
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作者 王涛 张锐 苏雪梅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第5期596-600,共5页
Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equa... Stationary entanglement in a four-mode optomechanical system,especially under room-temperature,is discussed.In this scheme,when the coupling strengths between the two target modes and the mechanical resonator are equal,the results cannot be explained by the Bogoliubov-mode-based scheme.This is related to the idea of quantummechanics-free subspace,which plays an important role when the thermal noise of the mechanical modes is considered.Significantly prominent steady-state entanglement can be available under room-temperature. 展开更多
关键词 four-mode optomechanics steady-state entanglement quantum-mechanics-free subspace
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Quantum Field Theory with a Minimal Length Induced from Noncommutative Space
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作者 林冰生 衡太骅 陈伟 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第5期605-610,共6页
From the inspection of noncommutative quantum mechanics, we obtain an approximate equivalent relation for the energy dependence of the Planck constant in the noncommutative space, which means a minimal length of the s... From the inspection of noncommutative quantum mechanics, we obtain an approximate equivalent relation for the energy dependence of the Planck constant in the noncommutative space, which means a minimal length of the space. We find that this relation is reasonable and it can inherit the main properties of the noncommutative space.Based on this relation, we derive the modified Klein–Gordon equation and Dirac equation. We investigate the scalar field and φ4model and then quantum electrodynamics in our theory, and derive the corresponding Feynman rules. These results may be considered as reasonable approximations to those of noncommutative quantum field theory. Our theory also shows a connection between the space with a minimal length and the noncommutative space. 展开更多
关键词 noncommutative space minimal length quantum field theory
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