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蔡元培与威廉·洪堡教育思想之比较研究 被引量:8
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作者 徐艳 《浙江海洋学院学报(人文科学版)》 2000年第3期27-34,共8页
对蔡元培和洪堡两位教育家的教育思想和实践做了一个粗略的比较,比较的重点是他们的教育独立观,他们对完全人格教育的看法以及他们的大学改革实践。
关键词 洪堡 教育思想 比较研究 个性 群性 普通教育 专门教育 高校 改革
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A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in aqueous solutions and its applications in binary and ternary aqueous solutions 被引量:1
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作者 杨学民 赵伟洁 +2 位作者 柴国明 郭汉杰 张强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期626-641,共16页
A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexi... A universal thermodynamic model of calculating mass action concentrations for structural units or ion couples in ternary and binary strong electrolyte aqueous solution was developed based on the ion and molecule coexistence theory and verified in four kinds of binary aqueous solutions and two kinds of ternary aqueous solutions. The calculated mass action concentrations of structural units or ion couples in four binary aqueous solutions and two ternary solutions at 298.15 K have good agreement with the reported activity data from literatures after shifting the standard state and concentration unit. Therefore, the calculated mass action concentrations of structural units or ion couples from the developed universal thermodynamic model for ternary and binary aqueous solutions can be applied to predict reaction ability of components in ternary and binary strong electrolyte aqueous solutions. It is also proved that the assumptions applied in the developed thermodynamic model are correct and reasonable, i.e., strong electrolyte aqueous solution is composed of cations and anions as simple ions, H2O as simple molecule and other hydrous salt compounds as complex molecules. The calculated mass action concentrations of structural units or ion couples in ternary and binary strong electrolyte aqueous solutions strictly follow the mass action law. 展开更多
关键词 universal thermodynamic model mass action concentration activity ternary aqueous solution binary aqueous solution ion and molecule coexistence theory structural units ion couples components
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DUAL QUATERNION CURVE INTERPOLATION ALGORITHM FOR FORMATION SATELLITES 被引量:1
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作者 李静 王惠南 刘海颖 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期90-95,共6页
The traditional algorithms for formation flying satellites treat the satellite position and attitude sepa- rately. A novel algorithm combining satellite attitude with position is proposed. The principal satellite traj... The traditional algorithms for formation flying satellites treat the satellite position and attitude sepa- rately. A novel algorithm combining satellite attitude with position is proposed. The principal satellite trajectory is obtained by dual quaternion interpolation, then the relative position and attitude of the deputy satellite are ob- tained by dual quaternion modeling on the principal satellite. Through above process, relative position and atti- tude are unified. Compared with the orbital parameter and the quaternion methods, the simulation result proves that the algorithm can unify position and attitude, and satisfy the precision requirement of formation flying satel- lites. 展开更多
关键词 formation satellites dual quaternion interpolation algorithm relative position and attitude
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Study of Object Oriented Petri Net and Its Application in Flexible Manufacturing Cells 被引量:1
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作者 何小燕 吴介一 罗军舟 《Journal of Southeast University(English Edition)》 EI CAS 1999年第2期37-42,共6页
This paper presents an object oriented Petri net (OOPN) schema to model the dynamic behaviors of a flexible manufacturing cells (FMCs). The OOPN paradigm incorporates the characteristics of a Petri net and OOP. It in... This paper presents an object oriented Petri net (OOPN) schema to model the dynamic behaviors of a flexible manufacturing cells (FMCs). The OOPN paradigm incorporates the characteristics of a Petri net and OOP. It increases the maintainability and reusability of objects in Petri net modeling, thus it has more powerful modeling and analysis abilities. 展开更多
关键词 OO Petri net flexible manufacturing cell
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The Multiplier Algebra of a Ternary Algebra 被引量:1
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作者 许天周 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期6-11,共6页
In this article, we have given the definition of the relative double multiplier (quasi-multiplier) on a ternary algebra,and studied the isomorphic problem of the multiplier algebra M(A,e) of a ternary algerbra A.
关键词 multiplier algebra ternary algebra relative arens product
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Analysis and Producing Causes of Available Sulphur Status quo(Rich or Insufficient) in Farmlands and Countermeasures in Dengzhou City
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作者 张有成 《Agricultural Science & Technology》 CAS 2014年第8期1348-1350,共3页
In the research, available sulphur in 4 700 soil samples was tested and analyzed in 2006-2007 in Dengzhou, and the results showed that available sulphur was insufficient in farmlands in Dengzhou for cereal crop and ab... In the research, available sulphur in 4 700 soil samples was tested and analyzed in 2006-2007 in Dengzhou, and the results showed that available sulphur was insufficient in farmlands in Dengzhou for cereal crop and about 60% farmlands with available sulphur belong to the farmlands with potential shortage of available sulphur for Cruciferae, Liliaceae and Leguminosae. Meanwhile, the producing causes were analyzed from the perspectives of fertilization structure and planting structure and the countermeasures were proposed in terms of sulphur movements in plants and characters. 展开更多
关键词 Available sulphur S Rich or insufficient COUNTERMEASURES
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Determination of Trace Elements in Potatoes by Flame Atomic Absorption Spectrometry
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作者 王宁芳 《Agricultural Science & Technology》 CAS 2014年第5期716-717,723,共3页
[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry (FAAS), the contents of variou... [Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry (FAAS), the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision. 展开更多
关键词 POTATO Flame atomic absorption spectrometry Trace elements Relative deviation PRECISION
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MULTIVARIATE ABSOLUTE DEGREE OF GREY INCIDENCE BASED ON DISTRIBUTION CHARACTERISTICS OF POINTS
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作者 张可 王岩 +1 位作者 辛江慧 许叶军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期145-151,共7页
The analysis result of absolute degree of grey incidence for multivariate time series is often inconsistent with the qualitative analysis. To overcome this shortage, a multivariate absolute degree of grey incidence ba... The analysis result of absolute degree of grey incidence for multivariate time series is often inconsistent with the qualitative analysis. To overcome this shortage, a multivariate absolute degree of grey incidence based on distribution characteristics of points is proposed. Based on the geometric description of multivariate time se- ries, the neighborhood extrema are extracted in the different regions, and a characteristic point set is constructed. Then according to the distribution of the characteristic point set, a characteristic point sequence reflecting the ge- ometric features of multivariate time series is obtained. The incidence analysis between multivariate time series is transformed into the relational analysis between characteristic point sequences, and a grey incidence model is established. The model possesses the properties of translational invariance, transpose and rank transform invari- ance, and satisfies the grey incidence analysis axioms. Finally, two cases are studied and the results prove the ef- fectiveness of the model. 展开更多
关键词 grey system absolute degree of grey incidences multivariate time series similarity measure
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Characterizations of EP, normal and Hermitian elements in rings using generalized inverses
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作者 马一琳 陈建龙 韩瑞珠 《Journal of Southeast University(English Edition)》 EI CAS 2017年第2期249-252,共4页
The properties and some equivalent characterizations of equal projection( EP), normal and Hermitian elements in a ring are studied by the generalized inverse theory. Some equivalent conditions that an element is EP ... The properties and some equivalent characterizations of equal projection( EP), normal and Hermitian elements in a ring are studied by the generalized inverse theory. Some equivalent conditions that an element is EP under the existence of core inverses are proposed. Let a∈R , then a is EP if and only if aa a^# = a^#aa . At the same time, the equivalent characterizations of a regular element to be EP are discussed.Let a∈R, then there exist b∈R such that a = aba and a is EP if and only if a∈R , a = a ba. Similarly, some equivalent conditions that an element is normal under the existence of core inverses are proposed. Let a∈R , then a is normal if and only if a^*a = a a^*. Also, some equivalent conditions of normal and Hermitian elements in rings with involution involving powers of their group and Moore-Penrose inverses are presented. Let a∈R ∩R^#, n∈N, then a is normal if and only if a^* a^+( a^#) n = a^# a*( a^+) ^n. The results generalize the conclusions of Mosiet al. 展开更多
关键词 equal projection(EP) elements normal elements Hermitian elements core inverse Moore-Penrose inverse group inverse
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SINS in-Flight Alignment Using Quaternion Error Models 被引量:11
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作者 WEI Chun-ling ZHANG Hong-yue 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2001年第3期166-170,共5页
The widely used conventional linearized error models or perturbation models are not effective to represent the nonlinear characteristics of SINS error propagation with large attitude errors.Error equations in terms of... The widely used conventional linearized error models or perturbation models are not effective to represent the nonlinear characteristics of SINS error propagation with large attitude errors.Error equations in terms of quaternion error are derived,and extended Kalman filter techniques are used to solve the in-flight alignment problems.In the case of small attitude errors,the nonlinear models can be reduced to conventional phi-angle models.The simulation results show that the proposed error models may improve the performance of alignment. 展开更多
关键词 inertial navigation initial alignment QUATERNION nonlinear filtering
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Orientation-dependent Hydrodynamic Instabilities from Chemo-Marangoni Cells to Large Scale Interfacial Deformations 被引量:9
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作者 石英 Kerstin Eckert 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第5期748-753,共6页
The interplay between chemistry and interfacial-tension-driven hydrodynamic instabilities has been studied experimentally. The system on hand consists of two immiscible liquids separated along an initially plane inter... The interplay between chemistry and interfacial-tension-driven hydrodynamic instabilities has been studied experimentally. The system on hand consists of two immiscible liquids separated along an initially plane interface at which an interfacial reaction takes place to produce in situ a surfactant. It is identified that the dynamics of the system depends on the orientation of the Hele-Shaw cell with respect to the vector of gravity. If the nele-Shaw cell is placed vertically, Marangoni cells with vigorous convection develop in both phases along a nearly planar interface. However, if the Hele-Shaw cell is tilted off the gravity, the instabilities in the system are characterized by the large scale interracial deformation with a spatio-temporal periodicity together with the chemo-Marangoni convection. The focus is on the exploration of the transition from the cellular mode to the large scale interfacial deformation. 展开更多
关键词 interfacial reaction in situ produced surfactant Marangoni convection interfacial deformation
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Finite element analysis of contact fatigue and bending fatigue of a theoretical assembling straight bevel gear pair 被引量:15
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作者 邓松 华林 +1 位作者 韩星会 黄松 《Journal of Central South University》 SCIE EI CAS 2013年第2期279-292,共14页
The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulat... The aim of this work is to propose a 3D FE model of a theoretical assembling straight bevel gear pair to analyze the contact fatigue on the tooth surface and the bending fatigue in the tooth root. Based on the cumulative fatigue criterion and the stress-life equation, the key meshing states of the gear pair were investigated for the contact fatigue and the bending fatigue. Then, the reliability of the proposed model was proved by comparing the calculation result with the simulation result. Further study was performed to analyze the variation of the contact fatigue stress and the bending fatigue stress under different loads. Furthermore, the roles of the driving pinion and the driven gear pair were evaluated in the fatigue life of the straight bevel gear pair and the main fatigue failure mode was determined for the significant gear. The results show that the fatigue failure of the driving pinion is the main fatigue failure for the straight bevel gear pair and the bending fatigue failure is the main fatigue failure for the driving pinion. 展开更多
关键词 straight bevel gear finite element method contact fatigue bending fatigue
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Electric Wheelchair Control System Using Brain-Computer Interface Based on Alpha-Wave Blocking 被引量:2
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作者 明东 付兰 +8 位作者 陈龙 汤佳贝 綦宏志 赵欣 周鹏 张力新 焦学军 王春慧 万柏坤 《Transactions of Tianjin University》 EI CAS 2014年第5期358-363,共6页
A brain-computer interface(BCI)-based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control... A brain-computer interface(BCI)-based electric wheelchair control system was developed, which enables the users to move the wheelchair forward or backward, and turn left or right without any pre-learning. This control system makes use of the amplitude enhancement of alpha-wave blocking in electroencephalogram(EEG) when eyes close for more than 1 s to constitute a BCI for the switch control of wheelchair movements. The system was formed by BCI control panel, data acquisition, signal processing unit and interface control circuit. Eight volunteers participated in the wheelchair control experiments according to the preset routes. The experimental results show that the mean success control rate of all the subjects was 81.3%, with the highest reaching 93.7%. When one subject's triggering time was 2.8 s, i.e., the flashing time of each cycle light was 2.8 s, the average information transfer rate was 8.10 bit/min, with the highest reaching 12.54 bit/min. 展开更多
关键词 electric wheelchair alpha-wave blocking brain-computer interface (BCI) success control rate
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Simultaneous diagonalization of two quaternion matrices
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作者 周建华 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期178-181,共4页
The simultaneous diagonalization by congruence of pairs of Hermitian quaternion matrices is discussed. The problem is reduced to a parallel one on complex matrices by using the complex adjoint matrix related to each q... The simultaneous diagonalization by congruence of pairs of Hermitian quaternion matrices is discussed. The problem is reduced to a parallel one on complex matrices by using the complex adjoint matrix related to each quaternion matrix. It is proved that any two semi-positive definite Hermitian quaternion matrices can be simultaneously diagonalized by congruence. 展开更多
关键词 semi-positive definite matrix quaternion matrix adjoint matrix CONGRUENCE
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Catalytic Conversion of Biomass-Derived Polyols into Para-xylene over SiO2-Modified Zeolites 被引量:2
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作者 Sheng-fei Wang Ming-hui Fan +1 位作者 Yu-ting He Quan-xin Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第4期513-520,I0003,共9页
This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromat... This work proved that biomass-based polyols (sorbitol, xylitol, erythritol, glycerol and ethanediol) were able to be converted into high-value chemical (p-xylene) by catalytic cracking of polyols, alkylation of aromatics, and the isomerization of xylenes over the SiO2-modified zeolites. Compared to the conventional HZSM-5 zeolite, the SiO2-containing zeolites considerably increased the selectivity and yield of p-xylene due to the reduction of external surface acidity and the narrowing of pore entrance. The influences of the methanol additive, reaction temperature, and types of polyols on the selectivity and yield of p-xylene were investigated in detail. Catalytic cracking of polyols with methanol significantly enhanced the production of p-xylene by the alkylation of toluene with methanol. The highest p-xylene yield of 10.9 C-mol% with a p-xylene/xylenes ratio of 91.1% was obtained over the 15wt%SiO2/HZSM-5 catalyst. The reaction pathway for the formation of p-xylene was addressed according to the study of the key reactions and the characterization of catalysts. 展开更多
关键词 Biomass-derived polyols PARA-XYLENE Catalytic conversion SiO2-modified HZSM-5
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Numerical method and model for calculating thermal storage time for an annular tube with phase change material 被引量:5
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作者 刘泛函 徐建新 +1 位作者 王辉涛 王华 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第1期217-226,共10页
For calculating the thermal storage time for an annular tube with phase change material (PCM), a novel method is proposed. The method is suitable for either low-temperature PCM or high-temperature PCM whose initial ... For calculating the thermal storage time for an annular tube with phase change material (PCM), a novel method is proposed. The method is suitable for either low-temperature PCM or high-temperature PCM whose initial temperature is near the melting point. The deviation fit is smaller than 8% when the time is below 2x104 s. Comparison between the predictions and the reported experimental data of thermal storage time at same conditions is investigated and good agreements have been got. Based on this method, the performance of the thermal storage unit and the role of natural convection are also investigated. Results show a linear relation between the maximum amount of stored heat and thermal storage time, and their ratio increases with the height of the thermal storage unit. As the thickness of the cavity increases, natural convection plays an increasingly important role in promoting the melting behavior of paraffin. When the thickness of the cavity is small, natural convection restrains the melting behavior of paraffin. 展开更多
关键词 natural convection energy storage modeling heat transfer mass transfer
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Diagnosis of uremia patients based on color space 被引量:2
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作者 WANG Xue-min SHAO Na +4 位作者 WANG Rui-yun SUN Ying-ying YU Zhi-feng JIANG Zhi-hao ZHOU Peng 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第1期38-44,共7页
Since traditional nail diagnosis is susceptible to objective factors such as illumination,medical experience,etc.,a nail diagnosis system of traditional Chinese medicine which combines objective nail image acquisition... Since traditional nail diagnosis is susceptible to objective factors such as illumination,medical experience,etc.,a nail diagnosis system of traditional Chinese medicine which combines objective nail image acquisition with information analysis is proposed and applied to the clinical research of nail diagnosis of uremia patients.Fifteen nail pictures of uremic patients were collected and segmented.The color information of nails was extracted.The relationship between the hemoglobin values of uremic patients and the values of color space before and after maintenance hemodialysis was analyzed by correlation analysis and multiple regression analysis.The experimental results show that the hemoglobin value of uremic patients have certain correlations with multiple color channels;before and after dialysis,there are significant changes in multiple channels;and the related multiple regression equation is established. 展开更多
关键词 nail classification nail color UREMIA correlation analysis paired t test multiple regression
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High-Order Binary Symmetry Constraints of a Liouville Integrable Hierarchy and Its Integrable Couplings
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作者 CHEN Lan-Xin SUN Ye-Peng ZHANG Jun-Xian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期540-544,共5页
A 3 × 3 matrix spectral problem and a Liouville integrable hierarchy are constructed by designing a new subalgebra of loop algebra A^-2. Furthermore, high-order binary symmetry constraints of the corresponding hi... A 3 × 3 matrix spectral problem and a Liouville integrable hierarchy are constructed by designing a new subalgebra of loop algebra A^-2. Furthermore, high-order binary symmetry constraints of the corresponding hierarchy are obtained by using the binary nonlinearization method. Finally, according to another new subalgebra of loop algebra A^-2, its integrable couplings are established. 展开更多
关键词 Liouville integrable hierarchy loop algebra symmetry constraint binary nonlinearization integrable coupling
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Measurements and thermodynamic modeling of liquid–liquid equilibria in ternary system 2-methoxy-2-methylpropane+p-cresol+water 被引量:5
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作者 Liejin Luo Dong Liu +1 位作者 Libo Li Yun Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第3期360-364,共5页
Liquid-liquid equilibrium (LLE) data for the ternary system 2-methoxy-2-methylpropane (methyl tert-butyl ether) + p-cresol + water was measured at atmospheric pressure and temperatures of 298.15 K and 313.15 K. ... Liquid-liquid equilibrium (LLE) data for the ternary system 2-methoxy-2-methylpropane (methyl tert-butyl ether) + p-cresol + water was measured at atmospheric pressure and temperatures of 298.15 K and 313.15 K. From the distribution coefficients and selectivity, it was found that 2-methoxy-2-methylpropane is an efficient solvent to extract p-cresol from wastewater. The consistency of the experimental tie-line data was verified with the Hand and Bachman equations. These data were also correlated with the non-random two liquid (NRTL) and universal quasi-chemical correlation activity coefficient (UN1QUAC) models to yield binary interac- tion parameters for p-cresol extraction process evaluation. Both models agreed with experiments very well, yet the NRTL model showed even smaller average deviation than the UNIQUAC model. 展开更多
关键词 Liquid-liquid equilibriaSolvent extractionWaste treatmentNRTLUNIQUACSimulation
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The Properties of Finitely Generated Shift-invariant Subspace in L_(2π)~2
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作者 薛明志 朱秀阁 田继善 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期69-75, ,共7页
In this paper, some properties of shift invariant subspace in Periodic wavelets theory are discussed.
关键词 shift invariant subspace periodic wavelets dual element
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