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数理式中符号和单位应怎样注释? 被引量:1
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作者 同任 《编辑学报》 CSSCI 北大核心 2001年第5期305-305,共1页
关键词 科技期刊 科技论文 数理式 符号 单位 注释方法 编辑工作
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Omega results for coefficients of Rankin-Selberg L-functions over sparse sequences
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作者 CUI Hanfang LAO Huixue 《纯粹数学与应用数学》 2024年第3期407-416,共10页
Ω results involving the coefficients of automorphic L-functions are important research object in analytic number theory.Let f be a primitive holomorphic cusp form.Denote by λ_(f×f)(n) the nth Fourier coefficien... Ω results involving the coefficients of automorphic L-functions are important research object in analytic number theory.Let f be a primitive holomorphic cusp form.Denote by λ_(f×f)(n) the nth Fourier coefficient of Rankin-Selberg L-function L(f×f,s).This paper combines Kühleitner and Nowak′s Omega theorem and the analytic properties of Rankin-Selberg L-functions to study Omega results for coefficients of Rankin-Selberg L-functions over sparse sequences,and establishes the asymptotic formula for Σ_(n≤x)λf×f(n^(m))(m=2,3). 展开更多
关键词 cusp form Rankin-Selberg L-function Omega theorem
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The theoretical expressions of wood thermal diffusivity
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作者 杨庆贤 杨绮 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期133-135,共3页
From viewpoint of chemical element and microstructure of wood, this paper makes a discussion on thermal diffusivity of wood and two theoretical expressions of thermal diffusivity for the choral and radial directions w... From viewpoint of chemical element and microstructure of wood, this paper makes a discussion on thermal diffusivity of wood and two theoretical expressions of thermal diffusivity for the choral and radial directions were derived. The thermal diffusivities of the choral and radial directions for about 20 species of trees were calculated with the derived theoretical expressions and compared with the experimental values. The average error of the theoretical values of thermal diffusivity was 7.5% for choral direction and 6.2% for radial direction. 展开更多
关键词 Thermal diffusivity Theoretical expression WOOD
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Theoretical expressions of thermal conductivity of wood 被引量:8
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作者 杨庆贤 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期43-46,共5页
In this paper, the theoretical expressions of wood thermal conductiv ity in the choral and radical direction are derived from the micro-structure of wood by applying some basic principles in physical mechanics. The t... In this paper, the theoretical expressions of wood thermal conductiv ity in the choral and radical direction are derived from the micro-structure of wood by applying some basic principles in physical mechanics. The thermal conduc tivities of about twenty species of trees were calculated by means of the expres sions and compared with its experimental values under the same condition. The av erage relative error is about 5%, so the calculation result is satisfactory. 展开更多
关键词 Thermal conductivity WOOD Choral direction Radical direction Theor etical expression
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Determinant Theory in Banach Algebras
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作者 许天周 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期19-24,共6页
A determinant theory is developed for Banach algebras and a characterization of those traced unital Banach algebras admitting a determinant is given.
关键词 TRACE winding number DETERMINANT K-theory group Banach algebra
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Invariant Determinants in Banach Algebras
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作者 许天周 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期25-29,共5页
The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a... The invariant determinants ha Banach algebras are discussed and a necessary and sufficient condition for those integral traced unital Barach algebra(A,τ) admitting a G-invari- ant determinant is obtained,where G is a group of trace preserving automorphisms of A. 展开更多
关键词 TRACE invariant determinant K-theory group Banach algebra
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Analysis of radial basis function interpolation approach 被引量:4
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作者 邹友龙 胡法龙 +3 位作者 周灿灿 李潮流 李长喜 Keh-Jim Dunn 《Applied Geophysics》 SCIE CSCD 2013年第4期397-410,511,共15页
The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical prop... The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical properties in the laboratory on the basis of physical rock datasets, which include the formation factor, viscosity, permeability, and molecular composition. However, this approach does not consider the effect of spatial distribution of the calibration data on the interpolation result. This study proposes a new RBF interpolation approach based on the Freedman's RBF interpolation approach, by which the unit basis functions are uniformly populated in the space domain. The inverse results of the two approaches are comparatively analyzed by using our datasets. We determine that although the interpolation effects of the two approaches are equivalent, the new approach is more flexible and beneficial for reducing the number of basis functions when the database is large, resulting in simplification of the interpolation function expression. However, the predicted results of the central data are not sufficiently satisfied when the data clusters are far apart. 展开更多
关键词 Inverse problems radial basis function interpolation new approach
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Stability analysis for nonlinear multi-variable delay perturbation problems
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作者 王洪山 张诚坚 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期193-196,共4页
This paper discusses the stability of theoretical solutions for nonlinear multi-variable delay perturbation problems (MVDPP) of the form x′(t)=f(x(t),x(t-τ 1(t)),...,x(t-τ m(t)),y(t),y(t-τ 1(t)),...,y(t-τ m(t... This paper discusses the stability of theoretical solutions for nonlinear multi-variable delay perturbation problems (MVDPP) of the form x′(t)=f(x(t),x(t-τ 1(t)),...,x(t-τ m(t)),y(t),y(t-τ 1(t)),...,y(t-τ m(t))), and εy′(t)=g(x(t),x(t-τ 1(t)),...,x(t-τ m(t)),y(t),y(t-τ 1(t)),...,y(t-τ m(t))), where 0<ε1. A sufficient condition of stability for the systems is obtained. Additionally we prove the numerical solutions of the implicit Euler method are stable under this condition. 展开更多
关键词 multi-variable delay perturbation problems Euler method stability INTERPOLATION
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Improvement of the Mirror Extending in Empirical Mode Decomposition Method and the Technology for Eliminating Frequency Mixing 被引量:32
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作者 赵进平 《High Technology Letters》 EI CAS 2002年第3期40-47,共8页
The mirror extending approach proposed by Zhao and Huang in EMD method is improved in this paper. Mirror extending manner of data is kept unchanged, but the approach for determining envelopes is changed. When the end ... The mirror extending approach proposed by Zhao and Huang in EMD method is improved in this paper. Mirror extending manner of data is kept unchanged, but the approach for determining envelopes is changed. When the end of data is obviously not extremum, the envelope is determined by the first inner extremum and the image value in the mirror, ignoring the value on the end. This improvement eliminates the frequency compression near the end and decreases the error. Meanwhile, tridiagonal equations are used and the calculation speed is much increased. The temporal process curve is more important in reflecting the real physical process and comparable with other phenomena. Frequency mixing in IMFs makes it impossible. A high frequency reconstruction (HFR) approach is proposed to eliminate common frequency mixing and reconstruct an IMF with all high frequency portions. By this approach, the IMFs without frequency mixing are obtained to express significative processes. The high frequency information restored in high frequency IMF can be extracted by general spectrum method. After obtaining IMFs by EMD method, some of the theoretical and technological issues still exist when using the IMFs. The consistency of IMFs with real physical process is discussed in detail. By virtue of the approach proposed in this paper, the EMD method can be widely used in various fields. 展开更多
关键词 empirical mode decomposition mirror extending intrinsic mode function high frequency reconstruction frequency mixing
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Measuring the Condition of Parking Lot by Image Processing
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作者 吴大勇 魏平 侯朝桢 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期232-237,共6页
Aim To study the parking management in the condition of vehicles' increasing. Methods The methods of pattern recognition and image processing were used to analyze the eigenvalues of parking lot images. Results ... Aim To study the parking management in the condition of vehicles' increasing. Methods The methods of pattern recognition and image processing were used to analyze the eigenvalues of parking lot images. Results The automatic identification of every parking place in the parking plot was realized. The automatic measuring of parked vehicle count and parking lot utilization was completed. Conclusion It can complete the real time recognition, and has some practicabilities. 展开更多
关键词 automatic measuring digital image processing pattern recognition
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A version management model of PDM system and its realization 被引量:2
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作者 钟诗胜 李涛 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期459-464,共6页
Based on the key function of version management in PDM system, this paper discusses the function and the realization of version management and the transitions of version states with a workflow. A directed aeyclic grap... Based on the key function of version management in PDM system, this paper discusses the function and the realization of version management and the transitions of version states with a workflow. A directed aeyclic graph is used to describe a version model. Three storage modes of the directed acyelic graph version model in the database, the bumping block and the PDM working memory are presented and the conversion principle of these three modes is given. The study indicates that building a dynamic product structure configuration model based on versions is the key to resolve the problem. Thus a version model of single product object is built. Then the version management model in product structure configuration is built and the application of version management of PDM syster is presented as a case. 展开更多
关键词 product data management (PDM) version management directed acyclic graph version model product structure configuration management
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An Equivalent Form of the Dedekind Axiomand Its Application(Ⅱ)——Also on the unity of the Continuous Induction,the Mathem atical Induction and the Transfinite Induction 被引量:1
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作者 萧治经 熊萍 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期24-28, ,共5页
In this paper,a common characteristic of real number system and well ordered set is revealed and proved to be an equivalent form of the Dedekind Axiom or the Continuous Induction in R. Basing on it,we get the unified ... In this paper,a common characteristic of real number system and well ordered set is revealed and proved to be an equivalent form of the Dedekind Axiom or the Continuous Induction in R. Basing on it,we get the unified form of the mathematical induction,the transfinite induction and the continuous induction and generalize induction to totally ordered set that has the same characteristic. 展开更多
关键词 mathematical induction transfinite induction continuous induction well order totally order Dedekinds Axiom
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An Equivalent Form of the Dedekind Axiomand Its Application(Ⅰ)——Also on theunity ofthe ContinuousInduction,theMathem aticalInduction and theTransfiniteInduction 被引量:1
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作者 萧治经 熊萍 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第3期74-80, ,共7页
In this paper,a common characteristic of real number system and well ordered set is revealed and proved to be an equivalent form of the Dedekind Axiom or the Continuous Induction in R. Basing on it,we get the unif... In this paper,a common characteristic of real number system and well ordered set is revealed and proved to be an equivalent form of the Dedekind Axiom or the Continuous Induction in R. Basing on it,we get the unified form of the mathematical induction,the transfinite induction and the continuous induction and generalize induction to totally ordered set that has the same characteristic. 展开更多
关键词 mathematical induction transfinite induction continuous induction well order totally order Dedekinds Axiom
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A Survey on Information-Centric Networking: Rationales, Designs and Debates 被引量:8
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作者 JIANG Xiaoke BI Jun +1 位作者 NAN Guoshun LI Zhaogeng 《China Communications》 SCIE CSCD 2015年第7期1-12,共12页
The basic function of the Internet is to delivery data(what) to serve the needs of all applications. IP names the attachment points(where) to facilitate ubiquitous interconnectivity as the current way to deliver data.... The basic function of the Internet is to delivery data(what) to serve the needs of all applications. IP names the attachment points(where) to facilitate ubiquitous interconnectivity as the current way to deliver data. The fundamental mismatch between data delivery and naming attachment points leads to a lot of challenges, e.g., mapping from data name to IP address, handling dynamics of underlying topology, scaling up the data distribution, and securing communication, etc. Informationcentric networking(ICN) is proposed to shift the focus of communication paradigm from where to what, by making the named data the first-class citizen in the network, The basic consensus of ICN is to name the data independent from its container(space dimension) and session(time dimension), which breaks the limitation of point-to-point IP semantic. It scales up data distribution by utilizing available resources, and facilitates communication to fit diverse connectivity and heterogeneous networks. However, there are only a few consensuses on the detailed design of ICN, and quite a few different ICN architectures are proposed. This paper reveals the rationales of ICN from the perspective of the Internet evolution, surveys different design choices, and discusses on two debatable topics in ICN, i.e.,self-certifying versus hierarchical names, and edge versus pervasive caching. We hope this survey helps clarify some mis-understandings on ICN and achieve more consensuses. 展开更多
关键词 information-centric networking content-centric networking future internet architecture named-data networking PUBLISH-SUBSCRIBE
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Numerical simulation for explosion wave propagation of combustible mixture gas 被引量:2
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作者 王成 宁建国 马天宝 《Journal of Central South University of Technology》 EI 2008年第3期361-367,共7页
A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based co... A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based combustible mixture gas. In the code,Young's technique was employed to track the interface between the explosion products and air,and combustible function model was adopted to simulate ignition process. The code was employed to study explosion flow field inside and outside the duct and to obtain peak pressures in different boundary conditions and ignition positions. Numerical results suggest that during the propagation in a duct,for point initiation,the curvature of spherical wave front gradually decreases and evolves into plane wave. Due to the multiple reflections on the duct wall,multi-peak values appear on pressure-time curve,and peak pressure strongly relies on the duct boundary conditions and ignition position. When explosive wave reaches the exit of the duct,explosion products expand outward and forms shock wave in air. Multiple rarefaction waves also occur and propagate upstream along the duct to decrease the pressure in the duct. The results are in agreement with one-dimensional isentropic gas flow theory of the explosion products,and indicate that the ignition model and multi-material interface treatment method are feasible. 展开更多
关键词 combustible mixture gas explosion wave interface treatment combustion function mode
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MAXIMUM LIKELIHOOD ESTIMATION FOR INSAR IMAGE CO-REGISTRATION 被引量:1
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作者 Li Xinglin Song Hongjun +3 位作者 Robert Wang Shao Yunfeng Zhang Zhiguang Yan He 《Journal of Electronics(China)》 2013年第6期553-560,共8页
This paper presents a closed-form robust phase correlation based algorithm for performing image registration to subpixel accuracy.The subpixel translational shift information is directly obtained from the phase of the... This paper presents a closed-form robust phase correlation based algorithm for performing image registration to subpixel accuracy.The subpixel translational shift information is directly obtained from the phase of the normalized cross power spectrum by using Maximum Likelihood Estimation(MLE).The proposed algorithm also has slighter time complexity.Experimental results show that the proposed algorithm yields superior registration precision on the Cramér-Rao Bound(CRB) in the presence of aliasing and noise. 展开更多
关键词 Cramer-Rao Bound (CRB) Interferometric Synthetic Aperture Radar (InSAR) Maximum Likelihood Estimation (MLE) Phase correlation Subpixel image registration
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Relocation Selection for Poverty Alleviation:Factor Analysis and GIS Modeling 被引量:2
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作者 LI Yimin YIN Haihong LIU Suhong 《Journal of Mountain Science》 SCIE CSCD 2011年第3期466-475,共10页
Resettlement is considered a major policy measure in two major Chinese policy programs,the "Great Development of the West" and poverty alleviation in the new century,and the "New Countryside Development... Resettlement is considered a major policy measure in two major Chinese policy programs,the "Great Development of the West" and poverty alleviation in the new century,and the "New Countryside Development".The selection of the target location of resettlement sites for poverty-stricken villages is of critical importance to the success of resettlement projects,yet the selection process is challenged by the need for analyzing a variety of contributing factors,and the need for many rounds of tedious data processing.So in this paper we present an in-depth analysis of the major factors and data processing model concerning mountainous povertystricken villages,which also takes a major part of China's poor villages.Our analysis shows the following factors bear the most importance in resettlement selection:1) topography:candidate areas should have slope less than 25 degrees and altitude less than 2400 meters.2) accessibility:close to market conventions places and transportation facilities.3) farming resources:with abundant land and water resources.4) non-intrusiveness:interests of receiving villages should be considered and negative impact minimized.A simple measure could be having the candidate area 1000 m away from the receiving residents.5) Minimal ecological and political footprint:candidate areas shall not conflict with nature conservation areas or nationally planned key land use projects.6) Social and cultural compatibility:residents will better off if relocated in the same county,considering language,religion,ethnic culture and other factors.Taking Makuadi,Lushui County of Nujiang Prefecture as a case study,we demonstrate how GIS analysis and modeling tools can be used in the selection process of resettlement projects in mountainous areas. 展开更多
关键词 RESETTLEMENT Makuadi village Geographic modeling GIS Analysis China
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Removal of PCDDs/Fs from municipal solid waste incineration by entrained-flow adsorption technology 被引量:8
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作者 YAN Jian-hua PENG Zheng +2 位作者 LU Sheng-yong LI Xiao-dong CEN Ke-fa 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第11期1896-1903,共8页
Entrained flow adsorption using activated carbon as the adsorbent is widely adopted for PCDDs/Fs-abatement in municipal solid waste incineration (MSWI) process. The effects of operating parameters including flue gas t... Entrained flow adsorption using activated carbon as the adsorbent is widely adopted for PCDDs/Fs-abatement in municipal solid waste incineration (MSWI) process. The effects of operating parameters including flue gas temperature, feeding rate of activated carbon, polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/Fs) concentration at the inlet of the air pollution control device (APCD), filter materials, pressure drop on PCDDs/Fs removal efficiency are reviewed and commented upon in this paper. Evaluation on the various mechanistic models for entrained flow adsorption is carried out based on the computational simulation in terms of the actual operating condition and theoretical analysis. Finally, an advancement of en- trained flow adsorption in combination of dual bag filter is introduced. 展开更多
关键词 PCDDs/Fs Entrained flow adsorption Operating parameters Mechanistic model Dual bag filters
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SLC-index: A scalable skip list-based index for cloud data processing 被引量:2
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作者 HE Jing YAO Shao-wen +1 位作者 CAI Li ZHOU Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第10期2438-2450,共13页
Due to the increasing number of cloud applications,the amount of data in the cloud shows signs of growing faster than ever before.The nature of cloud computing requires cloud data processing systems that can handle hu... Due to the increasing number of cloud applications,the amount of data in the cloud shows signs of growing faster than ever before.The nature of cloud computing requires cloud data processing systems that can handle huge volumes of data and have high performance.However,most cloud storage systems currently adopt a hash-like approach to retrieving data that only supports simple keyword-based enquiries,but lacks various forms of information search.Therefore,a scalable and efficient indexing scheme is clearly required.In this paper,we present a skip list-based cloud index,called SLC-index,which is a novel,scalable skip list-based indexing for cloud data processing.The SLC-index offers a two-layered architecture for extending indexing scope and facilitating better throughput.Dynamic load-balancing for the SLC-index is achieved by online migration of index nodes between servers.Furthermore,it is a flexible system due to its dynamic addition and removal of servers.The SLC-index is efficient for both point and range queries.Experimental results show the efficiency of the SLC-index and its usefulness as an alternative approach for cloud-suitable data structures. 展开更多
关键词 cloud computing distributed index cloud data processing skip list
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Three New Integrable Hierarchies of Equations
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作者 GUO Fu-Kui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期769-772,共4页
A general Lie algebra Vs and the corresponding loop algebra Vx are constructed, from which the linear isospectral Lax pairs are established, whose compatibility presents the zero curvature equation. As its application... A general Lie algebra Vs and the corresponding loop algebra Vx are constructed, from which the linear isospectral Lax pairs are established, whose compatibility presents the zero curvature equation. As its application, a new Lax integrable hierarchy containing two parameters is worked out. It is not Liouville-integrable, however, its two reduced systems are Liouville-integrable, whose Hamiltonian structures are derived by making use of the quadratic-form identity and the γ formula (i.e. the computational formula on the constant γ appeared in the trace identity and the quadratic-form identity). 展开更多
关键词 Lie algebra Hamiltonian structure quadratic-form identity
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