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Inverse full state hybrid projective synchronization for chaotic maps with different dimensions 被引量:3
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作者 Adel Ouannas Giuseppe Grassi 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期251-256,共6页
A new synchronization scheme for chaotic(hyperchaotic) maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach ... A new synchronization scheme for chaotic(hyperchaotic) maps with different dimensions is presented.Specifically,given a drive system map with dimension n and a response system with dimension m,the proposed approach enables each drive system state to be synchronized with a linear response combination of the response system states.The method,based on the Lyapunov stability theory and the pole placement technique,presents some useful features:(i) it enables synchronization to be achieved for both cases of n 〈 m and n 〉 m;(ii) it is rigorous,being based on theorems;(iii) it can be readily applied to any chaotic(hyperchaotic) maps defined to date.Finally,the capability of the approach is illustrated by synchronization examples between the two-dimensional H′enon map(as the drive system) and the three-dimensional hyperchaotic Wang map(as the response system),and the three-dimensional H′enon-like map(as the drive system) and the two-dimensional Lorenz discrete-time system(as the response system). 展开更多
关键词 chaotic map full state hybrid projective synchronization inverse problem maps with different dimensions
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Fixed-Time Adaptive Time-Varying Matrix Projective Synchronization of Time-Delayed Chaotic Systems with Different Dimensions
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作者 Peng Zheng Xiaozhen Guo Guoguang Wen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1451-1463,共13页
This paper deals with the fixed-time adaptive time-varying matrix projective synchronization(ATVMPS)of different dimensional chaotic systems(DDCSs)with time delays and unknown parameters.Firstly,to estimate the unknow... This paper deals with the fixed-time adaptive time-varying matrix projective synchronization(ATVMPS)of different dimensional chaotic systems(DDCSs)with time delays and unknown parameters.Firstly,to estimate the unknown parameters,adaptive parameter updated laws are designed.Secondly,to realize the fixed-time ATVMPS of the time-delayed DDCSs,an adaptive delay-unrelated controller is designed,where time delays of chaotic systems are known or unknown.Thirdly,some simple fixed-time ATVMPS criteria are deduced,and the rigorous proof is provided by employing the inequality technique and Lyapunov theory.Furthermore,the settling time of fixed-time synchronization(Fix-TS)is obtained,which depends only on controller parameters and system parameters and is independent of the system’s initial states.Finally,simulation examples are presented to validate the theoretical analysis. 展开更多
关键词 Time-varying matrix projective synchronization(TVMPS) fixed-time control unknown parameters different dimensions time-delayed chaotic systems(TDCSs)
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Computational Quantification of Map Projection Distortion by Fractal Dimension of Coastlines
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作者 Franklin Lee 《Journal of Applied Mathematics and Physics》 2024年第5期1890-1903,共14页
Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short w... Maps, essential tools for portraying the Earth’s surface, inherently introduce distortions to geographical features. While various quantification methods exist for assessing these distortions, they often fall short when evaluating actual geographic features. In our study, we took a novel approach by analyzing map projection distortion from a geometric perspective. We computed the fractal dimensions of different stretches of coastline before and after projection using the divide-and-conquer algorithm and image processing. Our findings revealed that map projections, even when preserving basic shapes, inevitably stretch and compress coastlines in diverse directions. This analysis method provides a more realistic and practical way to measure map-induced distortions, with significant implications for cartography, geographic information systems (GIS), and geomorphology. By bridging the gap between theoretical analysis and real-world features, this method greatly enhances accuracy and practicality when evaluating map projections. 展开更多
关键词 Map Projection Distortion COASTLINE Fractal dimension CARTOGRAPHY Geographic Information Systems
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Notes on pure projective modules
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作者 宋贤梅 陈建龙 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期506-508,共3页
Let R be an associated ring with identity. A new equivalent characterization of pure projective left R-modules is given by applying homological methods. It is proved that a left R-module P is pure projective if and on... Let R be an associated ring with identity. A new equivalent characterization of pure projective left R-modules is given by applying homological methods. It is proved that a left R-module P is pure projective if and only if for any pure epimorphism E→M→0, where E is pure injective, HomR(P, E)→HomR(P, M)→0 is exact. Also, we obtain a dual result of pure injective left R-modules. Furthermore, it is shown that every pure projective left R-module is closed under pure submodule if and only if every pure injective left R-module is closed under pure epimorphic image. 展开更多
关键词 pure projective left R-module pure injective left R-module pure submodule pure exact sequence
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Possibilities and challenges of expanding dimensions of waterway downstream of Three Gorges Dam 被引量:6
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作者 Tao Yan Yun-ping Yang +2 位作者 Yi-bing Li Yuan-fang Chai Xiao-bing Cheng 《Water Science and Engineering》 EI CAS CSCD 2019年第2期136-144,共9页
The waterway in the middle and lower reaches of the Yangtze River has long been known as the Golden Waterway and has served as an important link in the construction of the Yangtze River Economic Belt.Therefore,expandi... The waterway in the middle and lower reaches of the Yangtze River has long been known as the Golden Waterway and has served as an important link in the construction of the Yangtze River Economic Belt.Therefore,expanding its dimensions is a significant goal,particularly given the long-range cumulative erosion occurring downstream of the Three Gorges Dam (TGD),which has been concentrated in the dry river channel.With the regulation of the volume from upstream reservoirs and the TGD,the minimum discharge and water level of the river downstream are increasing,and creating favorable conditions for the increase of the depth of the waterway.The discharge compensation effect during the dry season offsets the decline in the water level of the river channel caused by the down-cutting of part of the riverbed,but the minimum navigable water level of the segment near the dam still shows a declining trend.In recent years,several waterway remediation projects have been implemented in the downstream reaches of the TGD and although the waterway depth and width have been increased,the channel dimensions are still insufficient in the Yichang-Anqing reach (with a total length of 1026 km),as compared to the upstream reservoir area and the deep water channel in the downstream tidal reaches.A comprehensive analysis of the water depth and the number and length of shoals in the waterway indicates that its dimensions can be increased to 4.5 m ×200 m and 6.0 m×200 m in the Yichang-Wuhan and Wuhan-Anqing reaches,respectively.This is also feasible given the remediation technologies currently available,but remediation projects need to be coordinated with those for flood prevention and ecological protection. 展开更多
关键词 WATERWAY dimension Condition analysis Three Gorges Project Yichang-Anqing REACH YANGTZE River
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On Ding homological dimensions 被引量:1
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作者 ZHU Hai-yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第4期491-502,共12页
In this paper, we investigate Ding projective dimensions and Ding injective di- mensions of modules and rings. Let R be a ring with rDPD(R) = n 〈 ∞, and let YYl = {Mild(M) 〈 ∞}. We prove that (DP,W1) is a co... In this paper, we investigate Ding projective dimensions and Ding injective di- mensions of modules and rings. Let R be a ring with rDPD(R) = n 〈 ∞, and let YYl = {Mild(M) 〈 ∞}. We prove that (DP,W1) is a complete hereditary cotorsion pair such that a module M belongs to DD∩W1 if and only if M is projective, moreover, 1421 = (M[pd(M) 〈 ∞} = {MIfd(M) ≤ n} = {MIpd(M) ≤ n}. Then we introduce and inves- tigate Ding derived functor Dext^i(-, -), and use it to characterize global Ding dimension. We show that if R is a Ding-Chen ring, or if R is a ring with rDPD(R) 〈≤ and rDID(R) 〈 ≤, then rDPD(R) 〈 n if and only if rDID(R) 〈 n if and only if Dext^n+i(M,N) = 0 for all modules M and N and all integer i ≥ 1. 展开更多
关键词 Ding projective (injective) dimension cotorsion pair derived functor.
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Cleft扩张下的余纯投射维数
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作者 陈秀丽 陈建龙 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2015年第2期264-266,共3页
令H为有限维Hopf代数且A为固定域k上的代数,AB为H-cleft扩张.利用cleft扩张和交叉积间的关系,证明了当H半单时,在cleft扩张下左余纯投射维数是不变的,并给出了A与B的QF性质.
关键词 cleft扩张 余纯投射维数 QF环
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Recursive super-convergence computation for multi-dimensional problems via one-dimensional element energy pro jection technique 被引量:11
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作者 Si YUAN Yue WU Qinyan XING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第7期1031-1044,共14页
This paper presents a strategy for computation of super-convergent solutions of multi-dimensional problems in the finite element method (FEM) by recursive application of the one-dimensional (1D) element energy pro... This paper presents a strategy for computation of super-convergent solutions of multi-dimensional problems in the finite element method (FEM) by recursive application of the one-dimensional (1D) element energy projection (EEP) technique. The main idea is to conceptually treat multi-dimensional problems as generalized 1D problems, based on which the concepts of generalized 1D FEM and its consequent EEP formulae have been developed in a unified manner. Equipped with these concepts, multi-dimensional problems can be recursively discretized in one dimension at each step, until a fully discretized standard finite element (FE) model is reached. This conceptual dimension-by- dimension (D-by-D) discretization procedure is entirely equivalent to a full FE discretization. As a reverse D-by-D recovery procedure, by using the unified EEP formulae together with proper extraction of the generalized nodal solutions, super-convergent displacements and first derivatives for two-dimensional (2D) and three-dimensional (3D) problems can be obtained over the domain. Numerical examples of 3D Poisson's equation and elasticity problem are given to verify the feasibility and effectiveness of the proposed strategy. 展开更多
关键词 three-dimensional(3D)problem generalized one-dimensional(1D)finiteelement method (FEM) dimension-by-dimension(D-by-D) super-convergence elementenergy projection(EEP)
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CONVERGENCE ANALYSIS FOR SYSTEM OF EQUILIBRIUM PROBLEMS AND LEFT BREGMAN STRONGLY RELATIVELY NONEXPANSIVE MAPPING
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作者 Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1081-1097,共17页
In this paper, we prove strong convergence theorems for approximation of a fixed point of a left Bregman strongly relatively nonexpansive mapping which is also a solution to a finite system of equilibrium problems in ... In this paper, we prove strong convergence theorems for approximation of a fixed point of a left Bregman strongly relatively nonexpansive mapping which is also a solution to a finite system of equilibrium problems in the framework of reflexive real Banach spaces. We also discuss the approximation of a common fixed point of a family of left Bregman strongly nonexpansive mappings which is also solution to a finite system of equilibrium problems in reflexive real Banach spaces. Our results complement many known recent results in the literature. 展开更多
关键词 left Bregman strongly relatively nonexpansive mapping left Bregman projection equilibrium problem Banach spaces
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Cotorsion Dimension of Weak Crossed Products
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作者 Chen Hua-xi Liang Jin-rong 《Communications in Mathematical Research》 CSCD 2018年第2期133-140,共8页
Let H be a finite-dimensional weak Hopf algebra over a field κ and A an associative algebra, and A#;H a weak crossed product. In this paper, a spectral sequence for Ext is constructed which yields an estimate for cot... Let H be a finite-dimensional weak Hopf algebra over a field κ and A an associative algebra, and A#;H a weak crossed product. In this paper, a spectral sequence for Ext is constructed which yields an estimate for cotorsion dimension of A#;H in terms of the corresponding data for H and A. 展开更多
关键词 weak crossed product cotorsion dimension projective resolution
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Statistics of Projected Motion in One Dimension of a D-Dimensional Random Walker
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作者 Jayeeta Chattopadhyay Muktish Acharyya 《Applied Mathematics》 2018年第6期602-617,共16页
We are studying the motion of a random walker in generalised d-dimensional continuum with unit step length (up to 10 dimensions) and its projected one dimensional motion numerically. The motion of a random walker in l... We are studying the motion of a random walker in generalised d-dimensional continuum with unit step length (up to 10 dimensions) and its projected one dimensional motion numerically. The motion of a random walker in lattice or continuum is well studied in statistical physics but what will be the statistics of projected one dimensional motion of higher dimensional random walker is yet to be explored. Here in this paper, by addressing this particular type of problem, it shows that the projected motion is diffusive irrespective of any dimension;however, the diffusion rate is changing inversely with dimensions. As a consequence, it can be predicted that for the one dimensional projected motion of infinite dimensional random walk, the diffusion rate will be zero. This is an interesting result, at least pedagogically, which implies that though in infinite dimensions there is diffusion, its one dimensional projection is motionless. At the end of the discussion we are able to make a good comparison between projected one dimensional motion of generalised d-dimensional random walk with unit step length and pure one dimensional random walk with random step length varying uniformly between -h to h where h is a “step length renormalizing factor”. 展开更多
关键词 HIGHER dimensions RANDOM WALK Projected WALK Renormalizing FACTOR Diffusive
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On Rings with Finite Global Gorenstein Dimensions
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作者 REN Wei ZHANG Yu 《Chinese Quarterly Journal of Mathematics》 2017年第3期255-260,共6页
As a proper setting to study Gorenstein projective and injective dimensions of modules via vanishing of Gorenstein Ext-functors, a notion of a generalized Gorenstein ring is introduced, which is a non-trivial generali... As a proper setting to study Gorenstein projective and injective dimensions of modules via vanishing of Gorenstein Ext-functors, a notion of a generalized Gorenstein ring is introduced, which is a non-trivial generalization of Gorenstein rings. Moreover, a new proof for Bennis and Mahdou's equality of global Gorenstein dimension is given. 展开更多
关键词 generalized Gorenstein ring Gorenstein projective(injective) dimension
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Relative Ding Projective Modules over Formal Triangular Matrix Rings
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作者 Hongyan Fan Xi Tang 《Journal of Applied Mathematics and Physics》 2023年第6期1598-1614,共17页
Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using t... Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using the left global relative Ding projective dimensions of A and B, we estimate the relative Ding projective dimension of a left T-module. 展开更多
关键词 Formal Triangular Matrix Ring Relative Ding projective Module Relative Ding projective dimension
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No One Left Behind
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作者 Ge Lijun 《ChinAfrica》 2016年第9期54-55,共2页
EVERY morning, fifth-grade schoolgirl Liu Lu goes to school with a smile on her face. But today little Liu and her classmates are even more excited, as they are looking forward to their favorite subject: art class. T... EVERY morning, fifth-grade schoolgirl Liu Lu goes to school with a smile on her face. But today little Liu and her classmates are even more excited, as they are looking forward to their favorite subject: art class. They will be taught for the first time how to use clay to create their own artworks. Liu has chosen to make a clay baby crocodile. 展开更多
关键词 PROJECT No One left Behind
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Rainfall Assimilation Using a New Four-Dimensional Variational Method:A Single-Point Observation Experiment
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作者 刘娟娟 王斌 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第4期735-742,共8页
Accurate forecast of rainstorms associated with the mei-yu front has been an important issue for the Chinese economy and society. In July 1998 a heavy rainstorm hit the Yangzi River valley and received widespread atte... Accurate forecast of rainstorms associated with the mei-yu front has been an important issue for the Chinese economy and society. In July 1998 a heavy rainstorm hit the Yangzi River valley and received widespread attention from the public because it caused catastrophic damage in China. Several numerical studies have shown that many forecast models, including Pennsylvania State University National Center for Atmospheric Research’s fifth-generation mesoscale model (MM5), failed to simulate the heavy precipitation over the Yangzi River valley. This study demonstrates that with the optimal initial conditions from the dimension-reduced projection four-dimensional variational data assimilation (DRP-4DVar) system, MM5 can successfully reproduce these observed rainfall amounts and can capture many important mesoscale features, including the southwestward shear line and the low-level jet stream. The study also indicates that the failure of previous forecasts can be mainly attributed to the lack of mesoscale details in the initial conditions of the models. 展开更多
关键词 data assimilation dimension-reduced projection four-dimensional variational data assimilation (DRP-4DVar) RAINSTORM numerical simulation
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New Exact Solutions for the Generalized (2 + 1)-dimensional Nonlinear Schroedinger Equation with Variable Coefficients
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作者 JIANG Zhi-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第2期224-231,共8页
With the help of the variable-coefficient generalized projected Ricatti equation expansion method, we present exact solutions for the generalized (2+1)-dimensional nonlinear SchrSdinger equation with variable coeff... With the help of the variable-coefficient generalized projected Ricatti equation expansion method, we present exact solutions for the generalized (2+1)-dimensional nonlinear SchrSdinger equation with variable coefficients. These solutions include solitary wave solutions, soliton-like solutions and trigonometric function solutions. Among these solutions, some are found for the first time. 展开更多
关键词 (2+1)-dimensions nonlinear SchrSdinger equation variable coefficients projected Ricatti equation expansion method
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A study of making use of computer-aided projection fringe system to measure breast dimension
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作者 查选平 《外科研究与新技术》 2005年第3期211-211,共1页
To measure breast basic dimension by using computer-aided projection fringe system.Methods A system has been developed for measuring breast basic dimension based on computer-aided projection fringe measurement and pro... To measure breast basic dimension by using computer-aided projection fringe system.Methods A system has been developed for measuring breast basic dimension based on computer-aided projection fringe measurement and programming software.Plastic manikins breast’s SN-N (sternal notch to nipple distance),N-ML (nipple to midline distance),N-N (internipple distance),MBW (base width of breast) and N-IMF (nipple to inframammary fold distance) are measured with this system.At the same time,these items are also measured with routine ruler.Results This study indicate that the system has some merits:① non-touching measurement;② it is very rapid,the patient measured need hold his breath only 0.5 second,and all the time it takes is about 2.5 minutes;③ the measurement’s sensitivity is as high as to 0.6 mm,which meets the clinic requirement entirely;④ the measurement’s accuracy of the system is not significantly when comparing to the routine ruler’s.Conclusion Computer-adided projection fringe system for measuring breast basic dimension is feasible and advanced.14 refs,1 fig. 展开更多
关键词 A study of making use of computer-aided projection fringe system to measure breast dimension
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Gorenstein稳定范畴的粘合和等价不变量
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作者 高楠 陈浩标 《南京师大学报(自然科学版)》 CAS 北大核心 2024年第2期1-7,共7页
引入了Gorenstein投射刚性维数,以Gorenstein投射模的稳定范畴的粘合为主要工具,证明了Gorenstein投射刚性维数是Morita等价、Gorenstein稳定等价和导出等价的不变量,刻画了某些代数类的Gorenstein投射刚性维数.
关键词 GORENSTEIN投射模 Gorenstein投射刚性维数 Gorenstein稳定等价 三角范畴的粘合
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关于n-纯同调维数的注记
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作者 吕家凤 金欣怡 《浙江师范大学学报(自然科学版)》 2024年第1期14-18,共5页
为了研究环与模的n-纯同调维数,通过同调的方法,分别给出了n-纯投射模与n-纯内射模的一些新刻画.作为应用,证明了环R的n-纯投射整体维数不超过1的充分必要条件是R的n-纯内射整体维数不超过1,得到了一个环R的n-纯投射整体维数与R的n-纯... 为了研究环与模的n-纯同调维数,通过同调的方法,分别给出了n-纯投射模与n-纯内射模的一些新刻画.作为应用,证明了环R的n-纯投射整体维数不超过1的充分必要条件是R的n-纯内射整体维数不超过1,得到了一个环R的n-纯投射整体维数与R的n-纯内射整体维数的对应关系. 展开更多
关键词 n-纯正合列 n-纯投射模 n-纯内射模 同调维数
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基于“五维四融”的应用型人才培养体系研究与实践——以工程造价专业为例
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作者 吴霞 《教育教学论坛》 2024年第16期185-188,共4页
在应用型教育背景下,我国部分院校在转型发展过程中存在一定的问题,在改革创新的过程中,须要采取强有力的措施进行突破。通过对我国应用型本科院校工程造价专业人才培养现状进行调研分析,提出构建“五维四融”人才培养体系,为工程造价... 在应用型教育背景下,我国部分院校在转型发展过程中存在一定的问题,在改革创新的过程中,须要采取强有力的措施进行突破。通过对我国应用型本科院校工程造价专业人才培养现状进行调研分析,提出构建“五维四融”人才培养体系,为工程造价专业人才培养、专业课程优化设置、“双师”教师培养、实践教学体系、校企共建教材、提高人才培养质量等提供依据和支撑条件。实施效果表明,对该培养体系进行推广和实施,具有重要的实践意义。 展开更多
关键词 “五维四融” 培养体系 工程造价 具体实施
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