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Identifying Proper Names Based on Association Analysis
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作者 张云涛 龚玲 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第5期559-562,共4页
The issue of proper names recognition in Chinese text was discussed. An automatic approach based on association analysis to extract rules from corpus was presented. The method tries to discover rules relevant to exter... The issue of proper names recognition in Chinese text was discussed. An automatic approach based on association analysis to extract rules from corpus was presented. The method tries to discover rules relevant to external evidence by association analysis, without additional manual effort. These rules can be used to recognize the proper nouns in Chinese texts. The experimental result shows that our method is practical in some applications. Moreover, the method is language independent. 展开更多
关键词 named entity recognition natural language processing text processing Chinese text proper name
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English Words from Proper Names
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作者 Fanmao Meng 《Sino-US English Teaching》 2006年第2期63-66,共4页
English has a large vocabulary. Many common words come from very different ways, among which one way of forming words is from proper names. These proper names have nowadays become widely used. They are well known to t... English has a large vocabulary. Many common words come from very different ways, among which one way of forming words is from proper names. These proper names have nowadays become widely used. They are well known to those who speak English. 展开更多
关键词 English words familiar words proper names
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Twin Paradox and Proper Time
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作者 Donald Lem 《Journal of Applied Mathematics and Physics》 2024年第1期12-15,共4页
Professors Mohazzbi and Luo [1] published “Despite several attempts have been made to explain the twin paradox … none of the explanations … resolved the paradox. If the paradox can be ever resolved, it requires a m... Professors Mohazzbi and Luo [1] published “Despite several attempts have been made to explain the twin paradox … none of the explanations … resolved the paradox. If the paradox can be ever resolved, it requires a much deeper understanding … of the theory of relativity”. The deeper understanding of resolving the paradox is by applying more explicit definitions of proper time interval, Lorentz transform, time dilation, and aging time. 展开更多
关键词 Twin Paradox proper Time Minkowski Metric Schwarzschild Metric
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A Model for Mechanical Property Evaluation of the Periodic Porous Low-k Materials by SAW
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作者 李志国 姚素英 +1 位作者 肖夏 白茂森 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第11期1722-1728,共7页
The influence of the distribution of nano-pores on the mechanical properties evaluation of porous low-k films by surface acoustic waves (SAW) is studied. A theoretical SAW propagation model is set up to characterize... The influence of the distribution of nano-pores on the mechanical properties evaluation of porous low-k films by surface acoustic waves (SAW) is studied. A theoretical SAW propagation model is set up to characterize the periodic porous dielectrics by transversely isotropic symmetry. The theoretical deductions of SAW propagating in the low-k film/Si substrate layered structure are given in detail. The dispersive characteristics of SAW in differ- ent propagation directions and the effects of the Young's moduli E, E′ and shear modulus G′ of the films on these dispersive curves are found. Computational results show that E′ and G′ cannot be measured along the propagation direction that is perpendicular to the nano-pores' direction. 展开更多
关键词 periodic porous materials low-k dielectrics transversely isotropic symmetry mechanical proper ty SAW measurement
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A-proper映射拓扑度的应用
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作者 黄晓芹 王绵森 《南昌大学学报(理科版)》 CAS 北大核心 2006年第6期525-526,530,共3页
利用A-proper映射拓扑度的基本性质,在投影完备的M enger PN-空间中研究了一些方程解的存在性。
关键词 MENGER PN-空间 A—proper映射 拓扑度
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一种D-ProPer保护框架下的差分隐私数据发布方法 被引量:1
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作者 邵荣敏 张琳 王汝传 《南京邮电大学学报(自然科学版)》 北大核心 2016年第5期96-104,共9页
差分隐私保护框架是实现差分隐私的基础环境。文中研究了满足PDP保护的Pro Per框架并对其改进应用到分布式环境中,提出了D-Pro Per差分隐私保护框架。在此框架下,针对GS分组划分方法在划分存在离群点的数据集时会造成巨大误差的问题,提... 差分隐私保护框架是实现差分隐私的基础环境。文中研究了满足PDP保护的Pro Per框架并对其改进应用到分布式环境中,提出了D-Pro Per差分隐私保护框架。在此框架下,针对GS分组划分方法在划分存在离群点的数据集时会造成巨大误差的问题,提出了满足ε差分隐私的S-GS数据发布方法。该方法是在原有GS划分方法的基础上引进差值集这一概念用于对数据集中存在的离群点进行判定,并对其进行针对性的划分,并进行了两组S-GS方法与GS方法的对比实验。实验结果表明,在拥有大量离群点的数据集中S-GS方法比GS方法有更强的算法鲁棒性以及更好的数据可用性。 展开更多
关键词 差分隐私 数据发布 proper GS方法
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PROPER CONDITIONS OF MESHING FOR Hy-Vo SILENT CHAIN AND SPROCKET 被引量:17
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作者 MENG Fanzhong LI Chun CHENG Yabing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第4期57-59,共3页
Proper meshing of Hy-Vo silent chain and sprocket is important for realizing the transmission of the silent chain with more efficiency and less noise. Based on the study of the meshing theory of the Hy-Vo silent chain... Proper meshing of Hy-Vo silent chain and sprocket is important for realizing the transmission of the silent chain with more efficiency and less noise. Based on the study of the meshing theory of the Hy-Vo silent chain with the sprocket and the roll cutting machining principle of the sprocket with the hob, the proper conditions of the meshing for the Hy-Vo silent chain and the sprocket are put forward with the variable pitch characteristic of the Hy-Vo silent chain taken into consideration, and the proper meshing design method on the condition that the value of the link tooth pressure angle is unequal to the value of the sprocket tooth pressure angle is studied. Experiments show that this new design method is feasible. In addition, the design of the pitch, the sprocket tooth pressure angle and the fillet radius of the sprocket addendum circle are studied. It is crucial for guiding the design of the hob which cuts the Hy-Vo silent chain sprocket. 展开更多
关键词 Hy-Vo silent chain Variable pitch proper meshing conditions Sprocket tooth pressure angle Sprocket hob Modification coefficient
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BENSON PROPER EFFICIENCY IN THE NEARLY CONE-SUBCONVEXLIKE VECTOR OPTIMIZATION WITH SET-VALUED FUNCTIONS 被引量:16
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作者 XuYihong LiuSanyang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期95-102,共8页
Some properties of convex cones are obtained and are used to derive several equivalent conditions as well as another important property for nearly cone-subconvexlike set-valued functions. Under the assumption of nearl... Some properties of convex cones are obtained and are used to derive several equivalent conditions as well as another important property for nearly cone-subconvexlike set-valued functions. Under the assumption of nearly cone-subconvexlikeness,a Lagrangian multiplier theorem on Benson proper efficiency is presented. Related results are generalized. 展开更多
关键词 nearly cone-subconvexlikeness convex cones Benson proper efficiency Lagrangian multiplier theorem.
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Inverse Method of Centrifugal Pump Impeller Based on Proper Orthogonal Decomposition (POD) Method 被引量:8
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作者 Ren-Hui Zhang Rong Guo +1 位作者 Jun-Hu Yang Jia-Qi Luo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期1025-1031,共7页
To improve the accuracy and reduce the calcu- lation cost for the inverse problem of centrifugal pump impeller, the new inverse method based on proper orthog- onal decomposition (POD) is proposed. The pump blade sha... To improve the accuracy and reduce the calcu- lation cost for the inverse problem of centrifugal pump impeller, the new inverse method based on proper orthog- onal decomposition (POD) is proposed. The pump blade shape is parameterized by quartic Bezier curve, and the initial snapshots is generated by introducing the perturbation of the blade shape control parameters. The internal flow field and its hydraulic performance is predicted by CFD method. The snapshots vector includes the blade shape parameter and the distribution of blade load. The POD basis for the snap- shots set are deduced by proper orthogonal decomposition. The sample vector set is expressed in terms of the linear combination of the orthogonal basis. The objective blade shape corresponding to the objective distribution of blade load is obtained by least square fit. The Iterative correction algorithm for the centrifugal pump blade inverse method based on POD is proposed. The objective blade load dis- tributions are corrected according to the difference of the CFD result and the POD result. The two dimensional and three dimensional blade calculation cases show that the proposed centrifugal pump blade inverse method based on POD have good convergence and high accuracy, and thecalculation cost is greatly reduced. After two iterations, the deviation of the blade load and the pump hydraulic perfor- mance are limited within 4.0% and 6.0% individually for most of the flow rate range. This paper provides a promising inverse method for centrifugal pump impeller, which will benefit the hydraulic optimization of centrifugal pump. 展开更多
关键词 Centrifugal impeller proper orthogonaldecomposition Inverse method Snapshot sets
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Coherency matrix-based proper orthogonal decomposition with application to wind field simulation 被引量:7
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作者 胡亮 李黎 +1 位作者 樊剑 方秦汉 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2006年第2期267-272,共6页
Proper Orthogonal Decomposition (POD) provides a powerful modal transformation tool for stochastic dynamics. In this paper, coherency matrix-based proper orthogonal decomposition (CPOD) is presented as an innovati... Proper Orthogonal Decomposition (POD) provides a powerful modal transformation tool for stochastic dynamics. In this paper, coherency matrix-based proper orthogonal decomposition (CPOD) is presented as an innovative form of the POD based on cross power spectral density matrices. By introducing a discretizing scheme, the CPOD-based spectral representation method is obtained for use in stochastic simulation. Moreover, some criteria are proposed that allow the truncation order of CPOD to be conveniently determined. A numerical example to illustrate the application of the proposed method for the simulation of a wind velocity field is provided. 展开更多
关键词 proper Orthogonal Decomposition coherency matrices order determination criteria wind field simulation
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Driving Mechanism of Cultivated Land Transition in Yantai Proper,Shandong Province,China 被引量:5
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作者 QIN Weishan ZHANG Yifeng LI Guangdong 《Chinese Geographical Science》 SCIE CSCD 2015年第3期337-349,共13页
Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the q... Cultivated land transition and its driving mechanism are the hotspots among studies on land use change. In this study, we constructed a framework to study the driving mechanism of cultivated land transition from the quantitative perspective. Based on the vector data of land use in 1990, 2000 and 2009 of Yantai Proper, Shandong Province China, 11 explanatory variables were chosen from two aspects: the elevation, slope, cost distance to major water area and cost distance to minor water area, which presented physical factors; cost distance to district center, cost distance to town center, cost distance to city expansion center, cost distance to major roads, cost distance to city roads, cost distance to county roads and cost distance to rural roads, which presented the socio-economic factors. Combined with spatial analysis tools and Logistic regression analysis model, we construct Logistic regression analyses with four objectives that were urban construction land, rural residential land, orchard and other lands. The results show that, cost distance to district center, cost distance to town center, cost distance to city expansion center and cost distance to city roads are the significant explanatory variables for the transition of cultivated land into urban construction land. The main explained factors on the transition of cultivated land into rural residential land are slope, cost distance to town center, cost distance to county roads and cost distance to rural roads. Slope, cost distance to minor water area, cost distance to town center, cost distance to county roads and cost distance to rural roads are the significant explanatory variables for the transition of cultivated land into orchard land. Elevation, slope, cost distance to major water area and cost distance to minor water area are the main explanatory variables on the transition of cultivated land into other land uses. 展开更多
关键词 cultivated land use transition driving mechanism Yantai proper China
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A Numerical Study on Hydraulic Fracturing Problems via the Proper Generalized Decomposition Method 被引量:5
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作者 Daobing Wang Sergio Zlotnik +3 位作者 Pedro Díez Hongkui Ge Fujian Zhou Bo Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第2期703-720,共18页
The hydraulic fracturing is a nonlinear,fluid-solid coupling and transient problem,in most cases it is always time-consuming to simulate this process numerically.In recent years,although many numerical methods were pr... The hydraulic fracturing is a nonlinear,fluid-solid coupling and transient problem,in most cases it is always time-consuming to simulate this process numerically.In recent years,although many numerical methods were proposed to settle this problem,most of them still require a large amount of computer resources.Thus it is a high demand to develop more efficient numerical approaches to achieve the real-time monitoring of the fracture geometry during the hydraulic fracturing treatment.In this study,a reduced order modeling technique namely Proper Generalized Decomposition(PGD),is applied to accelerate the simulations of the transient,non-linear coupled system of hydraulic fracturing problem,to match this extremely tight response time constraint.The separability of the solution in space and time dimensions is studied for a simplified model problem.The solid and fluid equations are coupled explicitly by inverting the solid discrete problem,and a simple iterative procedure to handle the non-linear characteristic of the hydraulic fracturing problem is proposed in this work.Numeral validation illustrates that the results of PGD match well with these of standard finite element method in terms o f fracture opening and fluid pressure in the hydro-fracture.Moreover,after the off-line calculations,the numerical results can be obtained in real time. 展开更多
关键词 Hydraulic fracturing proper generalized decomposition reduced order modeling numerical simulation.
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Coherent structures over riblets in turbulent boundary layer studied by combining time-resolved particle image velocimetry(TRPIV),proper orthogonal decomposition(POD),and finite-time Lyapunov exponent(FTLE) 被引量:4
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作者 Shan Li Nan Jiang +2 位作者 Shaoqiong Yang Yongxiang Huang Yanhua Wu 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期395-404,共10页
Time-resolved particle image velocimetry(TRPIV) experiments are performed to investigate the coherent structure's performance of riblets in a turbulent boundary layer(TBL) at a friction Reynolds number of 185. To... Time-resolved particle image velocimetry(TRPIV) experiments are performed to investigate the coherent structure's performance of riblets in a turbulent boundary layer(TBL) at a friction Reynolds number of 185. To visualize the energetic large-scale coherent structures(CSs) over a smooth surface and riblets, the proper orthogonal decomposition(POD) and finite-time Lyapunov exponent(FTLE) are used to identify the CSs in the TBL. Spatial-temporal correlation is implemented to obtain the characters and transport properties of typical CSs in the FTLE fields. The results demonstrate that the generic flow structures, such as hairpin-like vortices, are also observed in the boundary layer flow over the riblets, consistent with its smooth counterpart. Low-order POD modes are more sensitive to the riblets in comparison with the high-order ones,and the wall-normal movement of the most energy-containing structures are suppressed over riblets. The spatial correlation analysis of the FTLE fields indicates that the evolution process of the hairpin vortex over riblets are inhibited. An apparent decrease of the convection velocity over riblets is noted, which is believed to reduce the ejection/sweep motions associated with high shear stress from the viscous sublayer. These reductions exhibit inhibition of momentum transfer among the structures near the wall in the TBL flows. 展开更多
关键词 turbulent boundary layer RIBLETS proper orthogonal decomposition finite-time Lyapunov exponent
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Proper In deposition amount for on-demand epitaxy of InAs/GaAs single quantum dots 被引量:3
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作者 尚向军 徐建星 +8 位作者 马奔 陈泽升 魏思航 李密峰 查国伟 张立春 喻颖 倪海桥 牛智川 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第10期452-458,共7页
The test-QD in-situ annealing method could surmount the critical nucleation condition of InAs/GaAs single quantum dots(SQDs) to raise the growth repeatability.Here,through many growth tests on rotating substrates,we... The test-QD in-situ annealing method could surmount the critical nucleation condition of InAs/GaAs single quantum dots(SQDs) to raise the growth repeatability.Here,through many growth tests on rotating substrates,we develop a proper In deposition amount(θ) for SQD growth,according to the measured critical θ for test QD nucleation(θ;).The proper ratio θ/θ;,with a large tolerance of the variation of the real substrate temperature(T;),is 0.964-0.971 at the edge and> 0.989 but < 0.996 in the center of a 1/4-piece semi-insulating wafer,and around 0.9709 but < 0.9714 in the center of a 1/4-piece N;wafer as shown in the evolution of QD size and density as θ/θ;varies.Bright SQDs with spectral lines at 905 nm-935 nm nucleate at the edge and correlate with individual 7 nm-8 nm-height QDs in atomic force microscopy,among dense 1 nm-5 nm-height small QDs with a strong spectral profile around 860 nm-880 nm.The higher T;in the center forms diluter,taller and uniform QDs,and very dilute SQDs for a proper θ/θ;:only one 7-nm-height SQD in25 μm;.On a 2-inch(1 inch = 2.54 cm) semi-insulating wafer,by using θ/θ;= 0.961,SQDs nucleate in a circle in 22%of the whole area.More SQDs will form in the broad high-T;region in the center by using a proper θ/θ;. 展开更多
关键词 single quantum dot proper deposition amount on-chip distribution height statistics μPL spectra
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ON THE GENERALIZED FRITZ JOHN OPTIMALITY CONDITIONS OF VECTOR OPTIMIZATION WITH SET-VALUED MAPS UNDER BENSON PROPER EFFICIENCY 被引量:3
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1444-1451,共8页
A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condit... A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condition of set-valued optimization under Benson proper efficiency is established, its sufficience is discussed. The form of the optimality conditions obtained here completely tally with the classical results when the set-valued map is specialized to be a single-valued map. 展开更多
关键词 contingent tangent cone set-valued map Benson proper efficiency Fritz John condition
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PROPER SPLITTINGS FOR RESTRICTED LINEAR EQUATIONS AND THE GENERALIZED INVERSE A_(T,S)~2 被引量:2
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作者 王国荣 魏益民 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1998年第1期1-13,共13页
This paper presents a proper splitting iterative method for comparing the general restricted linear euqations Ax=b, x ∈T (where, b ∈AT, and T is an arbitrary but fixed subspace of C<sup>m</sup>) and th... This paper presents a proper splitting iterative method for comparing the general restricted linear euqations Ax=b, x ∈T (where, b ∈AT, and T is an arbitrary but fixed subspace of C<sup>m</sup>) and the generalized in A<sub>T,S</sub> For the special case when b ∈AT and dim(T)=dim(AT), this splitting iterative methverse A<sub>T,S</sub> hod converges to A<sub>T,S</sub>b (the unique solution of the general restricted system Ax=bx ∈T). 展开更多
关键词 proper SPLITTING RESTRICTED linear equations the generalized inverse A2T S.
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The proper orthogonal decomposition method for the Navier-Stokes equations 被引量:2
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作者 王阿霞 马逸尘 晏文璟 《Journal of Pharmaceutical Analysis》 SCIE CAS 2008年第3期141-148,共8页
The proper orthogonal decomposition (POD) method for the instationary Navier-Stokes equations is considered. Several numerical approaches to evaluating the POD eigenfunctions are presented. The POD eigenfunctions are ... The proper orthogonal decomposition (POD) method for the instationary Navier-Stokes equations is considered. Several numerical approaches to evaluating the POD eigenfunctions are presented. The POD eigenfunctions are applied as a basis for a Galerkin projection of the instationary Navier-Stokes equations. And a low-dimensional ordinary differential models for fluid flows governed by the instationary Navier-Stokes equations are constructed. The numerical examples show that the method is feasible and efficient for optimal control of fluids. 展开更多
关键词 proper orthogonal decomposition Navier-Stokes equations low-dimensional modeling Galerkin method
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Extension of Proper _-holom orphic Mappings 被引量:3
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作者 Su Jianbing (Department of Mathematics,Xuzhou Normal University,Xuzhou,221009) 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第3期59-63, ,共5页
In this paper,we prove that a proper μ holomorphic mapping f:D 1→D 2 between bounded domains with some convexity,such that f satisfies some growth condition,extends smoothly to bD 1-{z:U(z)=0}.
关键词 proper μ holomorphic mapping μ- projection bounded domain
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Model reduction for supersonic cavity flow using proper orthogonal decomposition(POD)and Galerkin projection 被引量:2
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作者 Chao ZHANG Zhenhua WAN Dejun SUN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第5期723-736,共14页
The reduced-order model (ROM) for the two-dimensional supersonic cavity flow based on proper orthogonal decomposition (POD) and Galerkin projection is investigated. Presently, popular ROMs in cavity flows are base... The reduced-order model (ROM) for the two-dimensional supersonic cavity flow based on proper orthogonal decomposition (POD) and Galerkin projection is investigated. Presently, popular ROMs in cavity flows are based on an isentropic assumption, valid only for flows at low or moderate Mach numbers. A new ROM is constructed involving primitive variables of the fully compressible Navier-Stokes (N-S) equations, which is suitable for flows at high Mach numbers. Compared with the direct numerical simulation (DNS) results, the proposed model predicts flow dynamics (e.g., dominant frequency and amplitude) accurately for supersonic cavity flows, and is robust. The comparison between the present transient flow fields and those of the DNS shows that the proposed ROM can capture self-sustained oscillations of a shear layer. In addition, the present model reduction method can be easily extended to other supersonic flows. 展开更多
关键词 supersonic cavity flow reduced-order model (ROM) proper orthogonal decomposition (POD) Galerkin projection
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Benson proper efficiency for vector optimization of generalized subconvexlike set-valued maps in ordered linear spaces 被引量:2
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作者 周志昂 《Journal of Shanghai University(English Edition)》 CAS 2010年第5期374-379,共6页
Several equivalent statements of generalized subconvexlike set-valued map are established in ordered linear spaces. Using vector closure, we introduce Benson proper efficient solution of vector optimization problem. U... Several equivalent statements of generalized subconvexlike set-valued map are established in ordered linear spaces. Using vector closure, we introduce Benson proper efficient solution of vector optimization problem. Under the assumption of generalized subconvexlikeness, scalarization, multiplier and saddle point theorems are obtained in the sense of Benson proper efficiency. 展开更多
关键词 set-valued maps vector closure generalized subconvexlikeness Benson proper efficient solution
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