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Degree of Compactness in I-fuzzy Topological Spaces 被引量:1
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作者 李宏艳 《Northeastern Mathematical Journal》 CSCD 2008年第6期485-491,共7页
In this paper, the concept of degree of compactness is introduced in the general framework of I-fuzzy topological spaces, and its property is discussed. All good compactness are generalized to I-fuzzy topological spac... In this paper, the concept of degree of compactness is introduced in the general framework of I-fuzzy topological spaces, and its property is discussed. All good compactness are generalized to I-fuzzy topological spaces accordingly. 展开更多
关键词 I-fuzzy topology value set of compactness degrees of compactness
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Bias-Free Solar-to-Hydrogen Conversion in a BiVO_(4)/PM6:Y6 Compact Tandem with Optically Balanced Light Absorption
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作者 Catarina G.Ferreira Constanza Sansierra +3 位作者 Francisco Bernal-Texca Mingyu Zhang Carles Ros Jordi Martorell 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期231-238,共8页
The high voltage required to overcome the thermodynamic threshold and the complicated kinetics of the water splitting reaction limit the efficiency of single semiconductor-based photoelectrochemistry.A semiconductor/s... The high voltage required to overcome the thermodynamic threshold and the complicated kinetics of the water splitting reaction limit the efficiency of single semiconductor-based photoelectrochemistry.A semiconductor/solar cell tandem structure has been theoretically demonstrated as a viable path to achieve an efficient direct transformation of sunlight into chemical energy.However,compact designs exhibiting the indispensable optimally balanced light absorption have not been demonstrated.In the current work,we design and implement a compact tandem providing the complementary absorption of a highly transparent BiVO_(4)photoanode and a PM6:Y6 solar cell.Such bandgap combination approaches the optimal to reach the solar-to-hydrogen(STH)conversion upper limit for tandem photoelectrochemical cells(PECs).We demonstrate that,by using a photonic multilayer structure to adequately balance sunlight absorption among both tandem materials,a 25%increase in the bias-free STH conversion can be achieved,setting a clear path to take compact tandem PECs to the theoretical limit performance. 展开更多
关键词 bismuth vanadate compact tandem organic solar cells photonic multilayers solar-to-hydrogen conversion
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Application of Compactness Detection to Complicated Concrete-Filled Steel Tube by Ultrasonic Method 被引量:1
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作者 杨建江 王飞 +1 位作者 陆苏亮 王川 《Transactions of Tianjin University》 EI CAS 2014年第2期126-132,共7页
An example of using ultrasonic method to detect the compactness of complicated concrete-filled steel tube in certain high-rise building was discussed in this study.Because of the particularity of the complicated concr... An example of using ultrasonic method to detect the compactness of complicated concrete-filled steel tube in certain high-rise building was discussed in this study.Because of the particularity of the complicated concrete-filled steel tubular column,the plane detection method and embedded sounding pipe method were adopted in the process of effectively detecting the column.According to the results of the plane detection method and embedded sounding pipe method,the cementing status of steel tube and concrete can be concluded,which cannot be judged by the hammering method in the rectangular steel tube-reinforced concrete. 展开更多
关键词 ultrasonic method concrete-filled steel tube plane detection method embedded sounding pipe method compactness
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Almost Fuzzy Compactness in L-fuzzy Topological Spaces
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作者 Li Hong-yan Cui Wei Lei Feng-chun 《Communications in Mathematical Research》 CSCD 2015年第3期267-273,共7页
In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characte... In this paper, the notion of almost fuzzy compactness is dened in L-fuzzy topological spaces by means of inequality, where L is a completely distributiveDeMorgan algebra. Its properties are discussed and many characterizations of it arepresented. 展开更多
关键词 L-fuzzy topological space L-fuzzy almost compactness L-fuzzy compactness almost fuzzy compactness
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Relative Strong F Compactness and Relative Ultra-F Compactness in L-topological Spaces
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作者 李尧龙 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期8-15,共8页
In this paper, two concepts of relative compactness-the relative strong fuzzy compactness and the relative ultra-fuzzy compactness are defined in L-topological spaces for an arbitrary L-set. Properties of relative str... In this paper, two concepts of relative compactness-the relative strong fuzzy compactness and the relative ultra-fuzzy compactness are defined in L-topological spaces for an arbitrary L-set. Properties of relative strong fuzzy sets and relative ultra-fuzzy compact sets are studied in detail and some characteristic theorems are given. Some examples are illustrated. 展开更多
关键词 Fuzzy topology complete latice relative strong F compactness relative ultra- F compactness coprime element remote neighborhood
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当归乙醇提取物抑制黑色素瘤B16-F10细胞增殖、诱导凋亡的作用及机制研究
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作者 柯佳杰 沈煜洲 +3 位作者 许雅苹 陈煜沛 陈培元 吴黉坦 《中国临床药理学与治疗学》 北大核心 2025年第1期51-60,共10页
目的:探究当归乙醇提取物(EEA)对黑色素瘤细胞B16-F10细胞增殖和凋亡的影响及其作用机制。方法:噻唑蓝(MTT)法评价细胞存活率;细胞克隆形成法检测细胞增殖能力;倒置显微镜观察细胞汇合度及形态变化;Hoechst 33342染色法检测细胞凋亡;流... 目的:探究当归乙醇提取物(EEA)对黑色素瘤细胞B16-F10细胞增殖和凋亡的影响及其作用机制。方法:噻唑蓝(MTT)法评价细胞存活率;细胞克隆形成法检测细胞增殖能力;倒置显微镜观察细胞汇合度及形态变化;Hoechst 33342染色法检测细胞凋亡;流式细胞术(FCM)检测细胞周期和凋亡;透射电镜(TEM)观察细胞线粒体形态结构变化;免疫印迹法(Western blot)检测细胞周期、凋亡、线粒体生物发生和动力学相关蛋白的表达情况。结果:与空白对照组相比,10~400μg/mL EEA处理24 h和48 h后,细胞存活率降低(P<0.05,P<0.01);100μg/mL和200μg/mL EEA处理24 h后,细胞汇合度下降,出现皱缩变圆、体积缩小等形态改变及染色质固缩等凋亡特征;10~200μg/mL EEA处理14 d后,细胞克隆数目减少(P<0.01);200μg/mLEEA处理24h后,细胞内线粒体变圆变短,其内容物严重破坏甚至消失;20~200μg/mL EEA处理24 h后,G0/G1期细胞比例增加(P<0.01),早期细胞凋亡率增加(P<0.01),活化胱天蛋白酶-9(cleaved caspase-9)和Bax蛋白表达升高(P<0.01),细胞周期蛋白D1(Cyclin D1)、Cyclin E、细胞周期蛋白依赖性激酶2(CDK2)、CDK4、Bcl-2、Bad、Bcl-XL、沉默信息调节因子2相关酶1(SIRT1)、过氧化物酶体增殖物激活受体γ辅助激活因子-1α(PGC-1α)、核呼吸因子1(NRF1)、线粒体转录因子A(TFAM)、线粒体融合蛋白2(MFN2)、视神经萎缩蛋白1(OPA1)蛋白表达降低(P<0.05,P<0.01),动力相关蛋白1(DRP1)和Fission 1蛋白(FIS1)表达升高(P<0.05,P<0.01)。结论:EEA对B16-F10细胞具有显著抑制作用,其机制可能与诱导细胞G1/S期阻滞,激活内源性线粒体途径细胞凋亡,破坏线粒体生物发生与动力学平衡有关。 展开更多
关键词 当归乙醇提取物 B16-f10细胞 细胞周期 凋亡 线粒体生物发生与动力学
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A COMPACTNESS THEOREM FOR STABLE FLAT SL(2, C) CONNECTIONS ON 3-FOLDS
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作者 Teng HUANG 《Acta Mathematica Scientia》 SCIE CSCD 2022年第3期1160-1172,共13页
Let Y be a closed 3-manifold such that all flat SU(2)-connections on Y are non-degenerate.In this article,we prove a Uhlenbeck-type compactness theorem on Y for stable flat SL(2,C)connections satisfying an L^(2)-bound... Let Y be a closed 3-manifold such that all flat SU(2)-connections on Y are non-degenerate.In this article,we prove a Uhlenbeck-type compactness theorem on Y for stable flat SL(2,C)connections satisfying an L^(2)-bound for the real curvature.Combining the compactness theorem and a result from[7],we prove that the moduli space of the stable flat SL(2,C)connections is disconnected under certain technical assumptions. 展开更多
关键词 Stable flat SL(2 C)connections Vafa-Witten equations compactness theorem
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VITEK■ 2 Compact全自动微生物鉴定药敏分析仪虚拟仿真教学软件的开发与应用
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作者 黄荔丰 《工业微生物》 CAS 2024年第3期31-34,共4页
文章主要介绍了VITEK■2 Compact全自动微生物鉴定药敏分析仪虚拟仿真教学软件的设计与开发,以及虚拟仿真融合线上线下混合教学模式在医学微生物检验实验教学中的应用。结果表明,该仿真教学软件的实际应用既有利于培养学生的实践操作能... 文章主要介绍了VITEK■2 Compact全自动微生物鉴定药敏分析仪虚拟仿真教学软件的设计与开发,以及虚拟仿真融合线上线下混合教学模式在医学微生物检验实验教学中的应用。结果表明,该仿真教学软件的实际应用既有利于培养学生的实践操作能力及思维方式,又能弥补学校实训环境与临床实际不符的缺陷,为微生物检验实验教学质量的提升开辟新的思路。 展开更多
关键词 VITEK■2 compact 虚拟仿真 微生物学检验 实验教学
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A NOTE IN APPROXIMATIVE COMPACTNESS AND MIDPOINT LOCALLY K-UNIFORM ROTUNDITY IN BANACH SPACES 被引量:4
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作者 刘春燕 张子厚 周宇 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期643-650,共8页
In this article, we prove the following results: (1) A Banach space X is weak midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively weakly compact k-Chebyshev set; (2) A ... In this article, we prove the following results: (1) A Banach space X is weak midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively weakly compact k-Chebyshev set; (2) A Banach space X is midpoint locally k-uniformly rotund if and only if every closed ball of X is an approximatively compact k-Chebyshev set. 展开更多
关键词 k-Chebyshev set approximatively weak compactness approximative compactness weak midpoint locally k-uniform rotundity midpoint locally k-uniform rotundity k-strict rotundity
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COMPACT FINITE DIFFERENCE-FOURIER SPECTRAL METHOD FOR THREE-DIMENSIONAL INCOMPRESSIBLE NAVIER-STOKES EQUATIONS 被引量:5
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作者 熊忠民 凌国灿 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1996年第4期296-306,共11页
A new compact finite difference-Fourier spectral hybrid method for solving the three dimensional incompressible Navier-Stokes equations is developed in the present paper. The fifth-order upwind compact finite differen... A new compact finite difference-Fourier spectral hybrid method for solving the three dimensional incompressible Navier-Stokes equations is developed in the present paper. The fifth-order upwind compact finite difference schemes for the nonlinear convection terms in the physical space, and the sixth-order center compact schemes for the derivatives in spectral space are described, respectively. The fourth-order compact schemes in a single nine-point cell for solving the Helmholtz equations satisfied by the velocities and pressure in spectral space is derived and its preconditioned conjugate gradient iteration method is studied. The treatment of pressure boundary conditions and the three dimensional non-reflecting outflow boundary conditions are presented. Application to the vortex dislocation evolution in a three dimensional wake is also reported. 展开更多
关键词 compact finite difference Fourier spectral method numerical simulation vortex dislocation
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Compactness for the commutators of multilinear singular integral operators with non-smooth kernels 被引量:2
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作者 BU Rui CHEN Jie-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2019年第1期55-75,共21页
In this paper, the behavior for commutators of a class of bilinear singular integral operators associated with non-smooth kernels on the product of weighted Lebesgue spaces is considered. By some new maximal functions... In this paper, the behavior for commutators of a class of bilinear singular integral operators associated with non-smooth kernels on the product of weighted Lebesgue spaces is considered. By some new maximal functions to control the commutators of bilinear singular integral operators and CMO(Rn) functions, compactness for the commutators is proved. 展开更多
关键词 singular integral OPERATOR maximal function weighted norm inequality COMMUTATOR compact OPERATOR
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COMPACTNESS FOR THE COMMUTATOR OF BOCHNER-RIESZ OPERATOR 被引量:1
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作者 卜瑞 陈杰诚 胡国恩 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1373-1384,共12页
Let α ∈0,(n-1)/2 and T~α be the Bochner-Riesz operator of order α. In this paper, for n = 2 and n ≥ 3, the compactness on Lebesgue spaces and Morrey spaces are considered for the commutator of Bochner-Riesz opera... Let α ∈0,(n-1)/2 and T~α be the Bochner-Riesz operator of order α. In this paper, for n = 2 and n ≥ 3, the compactness on Lebesgue spaces and Morrey spaces are considered for the commutator of Bochner-Riesz operator generated by CMO(R^n) function and T~α. 展开更多
关键词 Bochner-Riesz operator COMMUTATOR compact operator Fourier transform estimate
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ON COMPACTNESS FOR ITERATED COMMUTATORS 被引量:1
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作者 刘永民 于燕燕 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期491-500,共10页
The authors study the iterated commutators on the weighted Bergman spaces A2(φ), and prove that Cnh is compact on A2(φ) if and only if h ∈ B0.
关键词 Weighted Bergman space iterated commutator normal function littleBloch function compactness
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Measurement and Spatial Distribution of Urban Agglomeration Industrial Compactness in China 被引量:4
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作者 QI Weifeng FANG Chuanglin SONG Jitao 《Chinese Geographical Science》 SCIE CSCD 2008年第4期291-299,共9页
Urban agglomeration (UA) compactness means spatial concentration degree of physical entities, such as cities (towns), industries, resources, funds, traffic and technologies, whose concentration is formed according to ... Urban agglomeration (UA) compactness means spatial concentration degree of physical entities, such as cities (towns), industries, resources, funds, traffic and technologies, whose concentration is formed according to specified economic and technologic association in the process of UA formation and development. The UA industrial compactness means the concentration degree of industry and industry clusters with reference to the industrial, technologi- cal and economic relations among the cities in the UA in the process of rational industrial division and with the exten- sion of industrial chain. After analyzing the researches on compactness, this paper finds that the relevant measurement coefficient and methods reflecting industrial geographical concentration fail to link industries spatial concentration with urban spatial concentration. Taking 23 UAs as samples and classifying them by development degree, this paper probes into UA compactness and spatial distribution characteristics from the perspective of industry by adopting UA index systems of industry and measurement models. The research finds out: 1) there is obvious positive correlation between UA industrial compactness and UA development degree; 2) the spatial distribution difference of UA industrial compactness is relatively great; and 3) UA industrial compactness shows a gradually decreasing tendency from the eastern part, the middle part to the western part of China. From the research thoughts and approaches, this article suggests that studies on the UA integrated compactness measurement should be enhanced from a multidimensional perspective involving space, traffic, population density and so on. 展开更多
关键词 industrial compactness urban agglomeration(UA) China
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Magnetic properties and thermal stability of anisotropic bonded Nd-Fe-B magnets by warm compaction 被引量:1
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作者 TAO Siwua LU Xina +4 位作者 TIAN Jianjun QU Xuanhui Y. Honkura H. Mitarai K. Noguchi 《Rare Metals》 SCIE EI CAS CSCD 2009年第3期245-247,共3页
Anisotropic bonded magnets were prepared by warm compaction using anisotropic Nd-Fe-B powder. The forming process, magnetic properties, and temperature stability were studied. The results indicate that the optimal tem... Anisotropic bonded magnets were prepared by warm compaction using anisotropic Nd-Fe-B powder. The forming process, magnetic properties, and temperature stability were studied. The results indicate that the optimal temperature of the process, which was decided by the vis-cosity of the binders, was 110°C. With increasing pressure, the density of the magnets increased. When the pressure was above 700 MPa, the powder particles were destroyed and the magnetic properties decreased. The magnetic properties of the anisotropic bonded magnets were as follows: remanence Br=0.98 T, intrinsic coercivity iHc=1361 kA/m, and maximum energy product BHmax=166 kJ/m3. The magnets had excellent thermal stability because of the high coercivity and good squareness of demagnetization curves. The flux density of the magnets was 35% higher than that of isotropic bonded Nd-Fe-B magnets at 120°C for 1000 h. The flux density of the bonded magnets showed little change with regard to temperature. 展开更多
关键词 anisotropic magnets Nd-fe-B magnets warm compaction process magnetic properties thermal stability
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Research of warm compaction technology on nylon bonded Nd-Fe-B magnets 被引量:1
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作者 Xiuhai ZHANG Weihao XIONG Dameng YE Jun QU Zhenhua YAO 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第3期174-180,共7页
Warm compaction and room temperature compaction were applied to prepare bonded Nd-Fe-B magnets. The results indicated that the density of magnet was determined by the compaction pressure and warm compaction temperatur... Warm compaction and room temperature compaction were applied to prepare bonded Nd-Fe-B magnets. The results indicated that the density of magnet was determined by the compaction pressure and warm compaction temperature, whereas, the thermosetting temperature could hardly affect the density of magnet. The mechanical properties of magnets were the best when the thermosetting temperature was 200 ℃. The Br, Hob, and (BH)max of warm compaction magnet were higher than those of room compaction. When the warm compaction temperature and thermosetting temperature were invariable, the density of magnet increased with the increase of compaction pressure, which resulted in the increase of Br, Hcb, and (BH)max of magnet and the decrease of Hcj of magnet. When the warm compaction temperature and compaction pressure were invariable, the magnetic properties of magnets decreased with the increase of thermosetting temperature. The magnetic properties of warm compaction molding magnets were better than those of injection molding magnets. 展开更多
关键词 Bonded Nd-fe-B magnets Warm compaction molding Magnetic properties Mechanical properties
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STRONG COMPACTNESS OF APPROXIMATE SOLUTIONS TO DEGENERATE ELLIPTIC-HYPERBOLIC EQUATIONS WITH DISCONTINUOUS FLUX FUNCTION 被引量:1
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作者 Helge Holden Kenneth H. Karlsen +1 位作者 Darko Mitrovic Evgueni Yu. Panov 《Acta Mathematica Scientia》 SCIE CSCD 2009年第6期1573-1612,共40页
Under a non-degeneracy condition on the nonlinearities we show that sequences of approximate entropy solutions of mixed elliptic-hyperbolic equations are strongly precompact in the general case of a Caratheodory flux ... Under a non-degeneracy condition on the nonlinearities we show that sequences of approximate entropy solutions of mixed elliptic-hyperbolic equations are strongly precompact in the general case of a Caratheodory flux vector. The proofs are based on deriving localization principles for H-measures associated to sequences of measurevalued functions. This main result implies existence of solutions to degenerate parabolic convection-diffusion equations with discontinuous flux. Moreover, it provides a framework in which one can prove convergence of various types of approximate solutions, such as those generated by the vanishing viscosity method and numerical schemes. 展开更多
关键词 degenerate hyperbolic-elliptic equation degenerate convection-diffusion equation conservation law discontinuous flux approximate solutions compactness
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Investigation of compaction and sintering behavior of SiC powder after ultra-fine treatment 被引量:3
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作者 郭兴忠 杨辉 《Journal of Zhejiang University Science》 EI CSCD 2004年第8期950-955,共6页
Silicon carbide ceramics were prepared with SiC powder treated by the fluidized bed opposed jet mill as raw materials, and the effects of the ultra-fine treatment mechanism on the compaction and sintering behavior of ... Silicon carbide ceramics were prepared with SiC powder treated by the fluidized bed opposed jet mill as raw materials, and the effects of the ultra-fine treatment mechanism on the compaction and sintering behavior of SiC ceramics were investigated. The results showed that the compacts had higher density and microstructure homogeneity when the sintering temperature of the compact was decreased; and that the surface microstructure, densification and mechanical properties of the sintered body could be ameliorated obviously. 展开更多
关键词 SiC ceramic Ultra-fine treatment compaction efficiency Sintering behavior
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EQUI-ATTRACTION AND BACKWARD COMPACTNESS OF PULLBACK ATTRACTORS FOR POINT-DISSIPATIVE GINZBURG-LANDAU EQUATIONS 被引量:1
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作者 李扬荣 佘连兵 尹金艳 《Acta Mathematica Scientia》 SCIE CSCD 2018年第2期591-609,共19页
A new concept of an equi-attractor is introduced, and defined by the minimal compact set that attracts bounded sets uniformly in the past, for a non-autonomous dynam- ical system. It is shown that the compact equi-att... A new concept of an equi-attractor is introduced, and defined by the minimal compact set that attracts bounded sets uniformly in the past, for a non-autonomous dynam- ical system. It is shown that the compact equi-attraction implies the backward compactness of a pullback attractor. Also, an eventually equi-continuous and strongly bounded process has an equi-attractor if and only if it is strongly point dissipative and strongly asymptotically compact. Those results primely strengthen the known existence result of a backward bounded pullback attractor in the literature. Finally, the theoretical criteria are applied to prove the existence of both equi-attractor and backward compact attractor for a Ginzburg-Landau equation with some varying coefficients and a backward tempered external force. 展开更多
关键词 Non-autonomous systems point dissipative processes pullback attractors backward compact attractors equi-attractors Ginzburg-Landau equations
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Compactness of Composition Operators from the p-Bloch Space to the q-Bloch Space on the Classical Bounded Symmetric Domains 被引量:1
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作者 Jianbing Su Huijuan Li +1 位作者 Xingxing Miao Rui Wang 《Advances in Pure Mathematics》 2014年第12期649-664,共16页
In this paper, we introduce the weighted Bloch spaces on the first type of classical bounded symmetric domains , and prove the equivalence of the norms and . Furthermore, we study the compactness of composition operat... In this paper, we introduce the weighted Bloch spaces on the first type of classical bounded symmetric domains , and prove the equivalence of the norms and . Furthermore, we study the compactness of composition operator from to , and obtain a sufficient and necessary condition for to be compact. 展开更多
关键词 BLOCH Space Classical Bounded Symmetric DOMAINS Composition Operators compactness BERGMAN Metric
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