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Research on the Casting-forging Precision Forming Process of Alternator Poles 被引量:6
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作者 CHEN Hui-qin, WANG Quan-cong, GUO Hui-guang (Material Science and Engineering Department, Taiyuan Heavy Machinery Institute, Taiyuan 030024, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期4-5,共2页
The casting-forging combined technique and the closed die forging without flash-less are both new developed material working methods. The former can not only decrease forming operations of forgings, but also increase ... The casting-forging combined technique and the closed die forging without flash-less are both new developed material working methods. The former can not only decrease forming operations of forgings, but also increase the material utilization ratio. Therefore, it is applied to produce more complex forgings. The latter is required for forging precise parts without burrs. The alternator pole is a complex forging, which was usually produced by hot forging, upsetting-extrusion or upsetting-extrusion and bending processes. During these processes, not only the forming force is higher, but the material of burrs accounts for 30 percent or so of total required material. And burrs are difficult to remove in the sequential machining process. In accordance with defects exiting in current manufacturing of alternator poles by upsetting-extruding process, such as more material demand, higher forming force and difficulty of next machining, a casting-forging precision process of alternator poles was developed and investigated in this paper. In the process, the pole was formed by two operations. One is the pre-forming operation by casting. The other is the final forming operation by the closed precision forging process. This can not only shorten processes, decrease material and power demand, but also increase precision of forgings. First, the casting blocker was designed considering the casting process and the forging ratio and the mode of deformation. Then the die structure for closed precision forging was designed, and the closing device for forging dies with spring assemblies in order to provide the necessary closing force was also designed. Finally the forming processes was investigated by test and numerical simulation method to optimum process parameters and die structure design parameters. The result can provide basis for applying the process to manufacture poles in practice. 展开更多
关键词 alternator pole casting-forging precision forming process
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Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole 被引量:2
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作者 J.L.Song D.J.Hu Q.C.Wang H.Q.Chen H.G.Guo 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期79-82,共4页
As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the respons... As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future. 展开更多
关键词 ALTERNATOR claw-pole casting-forging NEAR NET forming NUMERICAL simulation
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Developments and perspectives on the precision forming processes for ultra-large size integrated components 被引量:17
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作者 Shijian Yuan Xiaobo Fan 《International Journal of Extreme Manufacturing》 2019年第2期34-51,共18页
In order to meet the requirements of high reliability,long-lifetime and lightweight in a new generation of aerospace,aviation,high-speed train,and energy power equipment,integrated components are urgently needed to re... In order to meet the requirements of high reliability,long-lifetime and lightweight in a new generation of aerospace,aviation,high-speed train,and energy power equipment,integrated components are urgently needed to replace traditional multi-piece,welded components.The applications of integrated components involve in a series of large-size,complex-shaped,highperformance components made of difficult-to-deform materials,which present a huge challenge for forming ultra-large size integrated components.In this paper,the developments and perspectives of several extreme forming technologies are reviewed,including the sheet hydroforming of ultra-large curved components,dieless hydroforming of ellipsoidal shells,radial-axial ring rolling of rings,in situ manufacturing process of flanges,and local isothermal forging of titanium alloy components.The principle and processes for controlling deformation are briefly illustrated.The forming of typical ultra-large size integrated components and industrial applications are introduced,such as the high strength aluminum alloy,3m in diameter,integrated tank dome first formed by using a sheet blank with a thickness the same as the final component,and a 16m diameter,integrated steel ring rolled by using a single billet.The trends for extreme forming of ultra-large size integrated components are discussed with a goal of providing ideas and fundamental guidance for the further development of new forming processes for extreme-size integrated components in the future. 展开更多
关键词 ultra-large size integrated components extreme forming HYDROforming radial-axial ring rolling isothermal forging
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Numerical study on forming complex fitting body on end of integrated stainless steel pipe without welds 被引量:2
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作者 张大伟 赵升吨 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第2期269-276,共8页
It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of pre... It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of preforming combined finish forming process is developed. The preforming process is characterized by flaring combined upsetting for left fitting body which is like a flange, and is characterized by tube axial compressive process under die constraint for right fitting body which is like a double-wall pipe. The finite element simulations of the processes are carried out by software package DEFORM, and the results indicate that: 1) left or right fitting body can be formed by a two-step forming process without folding and under-filling defects; 2) by using two-step forming, strain and stress in left fitting body are larger than those in right fitting body, and deformation in right fitting body is more homogenous than the deformation in left fitting body; 3) two or more preforming steps may be needed for left fitting body considering the distributions of strain and stress. 展开更多
关键词 复杂接头 焊缝成形 不锈钢管 数值研究 一体化 成形过程 应力分布 预成形工艺
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FORMING FREEFORM SURFACE SHEET METAL USING INTEGRATED REVERSE ENGINEERING TECHNOLOGY
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作者 邢渊 《Journal of Shanghai Jiaotong university(Science)》 EI 2001年第2期216-220,共5页
This paper presented a model of integrated reverse engineering system and set up its various data output flowchart, which is easy to be associated with other systems. The idea of integrated reverse engineer is introdu... This paper presented a model of integrated reverse engineering system and set up its various data output flowchart, which is easy to be associated with other systems. The idea of integrated reverse engineer is introduced to the system of forming sheet metal with complex surface and using IDEF0 method sets up the function model of the system. The freeform surface reconstruction and CAD modeling of the system are described and decomposed. This paper discussed some problems, such as the feature expression, feature modeling and feature translation of the sheet parts and dies. 展开更多
关键词 system integration reverse engineering sheet metal forming
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FEM equivalent model for press bend forming of aircraft integral panel 被引量:12
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作者 阎昱 万敏 王海波 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第2期414-421,共8页
An original plastic equivalent model was proposed to solve the problem of excessive FEM simulation time when designing the press bend forming path and optimizing the process parameters of press bend forming of the int... An original plastic equivalent model was proposed to solve the problem of excessive FEM simulation time when designing the press bend forming path and optimizing the process parameters of press bend forming of the integrally stiffened aircraft panels. Based on the in-depth analysis of the mechanics of the bending and springback of the detailed model and the equivalent model of the integral panels,the plastic equivalent model of the virtual material with special initial yield stress and hardening coefficients was constructed. FEM results indicate that the objective of getting the similar contour with the same press bend forming path is achieved with the error less than 6%,and the efficiency of FEM simulation is improved by more than 80%. The plastic equivalent model is valuable and essential for the further research on the press bend forming process of large scale complicated integral panels. 展开更多
关键词 弯曲成形 有限元模型 飞机 有限元模拟 等效模型 组成 优化工艺参数 成形路径
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Optimization of press bend forming path of aircraft integral panel 被引量:6
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作者 阎昱 万敏 +1 位作者 王海波 黄霖 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第2期294-301,共8页
In order to design the press bend forming path of aircraft integral panels,a novel optimization method was proposed, which integrates FEM equivalent model based on previous study,the artificial neural network response... In order to design the press bend forming path of aircraft integral panels,a novel optimization method was proposed, which integrates FEM equivalent model based on previous study,the artificial neural network response surface,and the genetic algorithm.First,a multi-step press bend forming FEM equivalent model was established,with which the FEM experiments designed with Taguchi method were performed.Then,the BP neural network response surface was developed with the sample data from the FEM experiments.Furthermore,genetic algorithm was applied with the neural network response surface as the objective function. Finally,verification was carried out on a simple curvature grid-type stiffened panel.The forming error of the panel formed with the optimal path is only 0.098 39 and the calculating efficiency has been improved by 77%.Therefore,this novel optimization method is quite efficient and indispensable for the press bend forming path designing. 展开更多
关键词 弯曲成形 路径积分 新闻界 面板 优化 飞机 神经网络响应面 有限元方法
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Research on the Comparison and Integration of Chinese and Western Music Cultures
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作者 LEI Shuwen 《Cultural and Religious Studies》 2024年第1期32-35,共4页
This research undertakes a nuanced examination of the intersections and distinctions between these two diverse musical traditions.Employing a meticulous comparative analysis,the study scrutinizes fundamental musical e... This research undertakes a nuanced examination of the intersections and distinctions between these two diverse musical traditions.Employing a meticulous comparative analysis,the study scrutinizes fundamental musical elements such as scales,modes,and compositional styles,illuminating shared threads and distinctive attributes that characterize Chinese and Western music.Against the backdrop of contemporary global dynamics,the research investigates the ongoing integration of these musical cultures.It explores the impact of globalization and technological advancements,revealing instances of cross-cultural collaboration and the emergence of hybrid musical forms.Augmenting theoretical discussions with concrete case studies,the paper offers illuminating examples of how Chinese and Western musical elements interweave,contributing to the evolving landscape of global music.This research not only advances scholarly understanding but also contributes practical insights for musicians,educators,and enthusiasts navigating the evolving dynamics of cross-cultural musical expression.By elucidating the intricate relationship between Chinese and Western music cultures,the paper underscores the richness borne out of their interaction and the cultural synthesis that defines contemporary musical landscapes. 展开更多
关键词 comparative music analysis cross-cultural integration hybrid forms globalization influence
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Historical-Dynamic Integrative Classification of Basinogenesis and Ore-Forming Basins
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作者 Chen GuodaChangsha Institute of Geotectonics, Academa Sinica, Changsha 410083 《Journal of Earth Science》 SCIE CAS CSCD 1993年第1期6-11,共6页
Interesting classifications of basinogenesis and basins were proposed by many scientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamic angle . I... Interesting classifications of basinogenesis and basins were proposed by many scientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamic angle . In order to more comprehensively understand them for more effectively guiding prospecting and exploration, the author integrates the two methods of analysis with each other and proposes an integrative classification .According to the historical - dynamic integrative classification,basinogenesis and basins can be.di-vided into three types :oceanic crust type ,embryo-continental (transitional )crust type and continental crust type .Oceanic crust type can be subdivided into mobile region type (mainly tenskmal )and stable region type . Embryo-continental type includes pre-geosynclinal type (divisible into several mobile region types and stable region types with tensional type predominating among mobile region types ) and ear ly-geosynclinal type (mainly tenskmal ) .Continental crust type includes late- geosynclinal (fold belt)type (compressional or tenskmal ),platform type (mainly sinking and rarely tenskmal subsidence-aulacogen)and geodepression (diwa )type (compressional , tenskmal or compresskmal-tenskmal ). 展开更多
关键词 basinogenesis and ore-forming basin historical-dynamic integrative classification oceanic crust type embryo-continental (transitional) crust type continental crust type pre-geosynclinal type geosynclinal type pbtform type geodepression
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HISTORICAL-DYNAMIC INTEGRATIVE CLASSIFICATION OF BASINOGENESIS AND ORE-FORMING BASINS
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作者 CHEN Guoda (Chang sha Institnte of Geutectunics, A cad emia Sinica, Chang sha 410013) 《Geotectonica et Metallogenia》 1994年第Z1期1-26,共26页
Interesting classifications of basinogenesis and basins were proposed by many seientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamie angle. In... Interesting classifications of basinogenesis and basins were proposed by many seientists. They classified basinogenesis and basins mainly from a single angle, either from a historical angle or from a dynamie angle. In order to more comprehensively understand them for moore effectively guidlilg prospeeting and exploration, the author integrates the two methods of analysis wilh cach other and proposes an integrative classification. According to the historieal-dynamic integrative classification, basinogenesis and basins can be divided into three types: occanic erust type. embryo-continental (transitional ) erust iype and continental crust type. Oceanie erust type call be subdivided into mobile region type (mainly tensional) and stable region type. Embryo-continental type includes pre-geosynclinal type (divisible into several mobile region types and stable region types with tensional type predoiminating among mobile region trpes) and early-geosynelinal type (mainly tensional). Continental erust type ineludes late-gcosynelinal (fold belt) type (compressional or tensional), platform type (mainly sinking and rarely tensional subsidence-aulacogen) and gcodepression (diwa) type (compressional, tensional or compressional-tensional ). 展开更多
关键词 basinogenesis and ORE-forming basin historical-dynamic integrATIVE classification oceanic CRUST TYPE embryo-continental (transitional) CRUST TYPE CONTINENTAL CRUST TYPE pre-geosynelinal TYPE geosynclinal TYPE platform TYPE geodepression (di
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An Integration of Meaning-Focused and Form-Focused Approach in EFL Reading and Writing——a Conceptual Inquiry and Experiment
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作者 王智杰 《海外英语》 2017年第22期247-248,250,共3页
Whether to adopt the meaning-oriented or form-oriented approach in EFL teaching has been in hot academic debate in the past decades. This paper investigates the literature contribution on these two methods, attempts a... Whether to adopt the meaning-oriented or form-oriented approach in EFL teaching has been in hot academic debate in the past decades. This paper investigates the literature contribution on these two methods, attempts an integration of the two,and introduces a teaching experiment of EFL reading and writing at China Agricultural University. 展开更多
关键词 integrATION MEANING form College English Reading and Writing
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General Integral Formulasof (0, q)(q 〉 0)Differential Forms on the Analytic Varieties 被引量:3
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作者 CHEN Shu-jin 《Chinese Quarterly Journal of Mathematics》 2017年第4期355-370,共16页
In this paper, firstly using different method and technique we derive the cor-responding integral representation formulas of (0, q)(q 〉 0) differential forms for the twotypes of the bounded domains in complex sub... In this paper, firstly using different method and technique we derive the cor-responding integral representation formulas of (0, q)(q 〉 0) differential forms for the twotypes of the bounded domains in complex submanifolds with codimension-m. Secondly weobtain the unified integral representation formulas of (0, q)(q 〉 0) differential forms for thegeneral bounded domain in complex submanifold with codimension-m, which include Hatzi-afratis formula, i.e. Koppelman type integral formula for the bounded domain with smoothboundary in analytic varieties. In particular, when m -- 0, we obtain the unified integralrepresentation formulas of (0, q)(q 〉 0) differential forms for general bounded domain in Cn,which are the generalization and the embodiment of Koppelman-Leray formula. 展开更多
关键词 Complex SUBMANIFOLD ANALYTIC VARIETIES UNIFIED formULA Extension Differ-ential form integral representation
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Viscous Inner and Outer Pressure Forming Method of Thin-walled Tube and Its Application 被引量:3
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作者 高铁军 LIU Yang WANG Zhongjin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第2期404-407,共4页
Aiming at overcoming the difficulties in integral forming of thin-walled tubes with complex shapes, a novel forming method by inner and outer pressure through viscous was proposed. In this method, by dividing large de... Aiming at overcoming the difficulties in integral forming of thin-walled tubes with complex shapes, a novel forming method by inner and outer pressure through viscous was proposed. In this method, by dividing large deformation of the part into inner and outer pressure forming deformations, the limit deformation of tube part can be increased by several times. Meanwhile, the principle of viscous inner and outer pressure forming was provided, and key problems during the forming process such as reduction of the wall-thickness and instability wrinkling were analyzed. Thereby, the complex curved surface super-alloy GH3044 thin-walled tube with varying diameter ratio of 1.35(the ratio between the maximum and minimum diameters of the part) can be integrally formed by this method. The experimental surface of the formed part is superior in quality and the wall-thickness distribution is uniform. The results show that the viscous inner and outer pressure forming can provide a new approach for integral forming of thin-walled tubes with complex shapes. 展开更多
关键词 thin-walled tube inner and outer pressure forming viscous medium integral forming
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INVARIANT FORM AND INTEGRAL INVARIANTS ON KAHLER MANIFOLD
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作者 张荣业 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第2期269-278,共10页
The important notions and results of the integral invariants of Poincard and Cartan-Poincard and the relationship between integral invariant and invariant form established first by E. Cartan in the classical mechanics... The important notions and results of the integral invariants of Poincard and Cartan-Poincard and the relationship between integral invariant and invariant form established first by E. Cartan in the classical mechanics are generalized to Hamilton mechanics on Kiihler manifold, by the theory of modern geometry and advanced calculus, to get the corresponding wider arid deeper results. differential 展开更多
关键词 Kahler manifold symplectic manifold invariant form integral invariant vector field form field Lie derivative exterior differential
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Hidden Properties of Mathematical Physics Equations. Double Solutions. The Realization of Integrable Structures. Emergence of Physical Structures and Observable Formations
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作者 L. I. Petrova 《Journal of Applied Mathematics and Physics》 2020年第7期1255-1262,共8页
With the help of skew-symmetric differential forms the hidden properties of the mathematical physics equations are revealed. It is shown that the equations of mathematical physics can describe the emergence of various... With the help of skew-symmetric differential forms the hidden properties of the mathematical physics equations are revealed. It is shown that the equations of mathematical physics can describe the emergence of various structures and formations such as waves, vortices, turbulent pulsations and others. Such properties of the mathematical physics equations, which are hidden (they appear only in the process of solving these equations), depend on the consistency of derivatives in partial differential equations and on the consistency of equations, if the equations of mathematical physics are a set of equations. This is due to the integrability of mathematical physics equations. It is shown that the equations of mathematical physics can have double solutions, namely, the solutions on the original coordinate space and the solutions on integrable structures that are realized discretely (due to any degrees of freedom). The transition from the solutions of the first type to one of the second type describes discrete transitions and the processes of origin of various structures and observable formations. Only mathematical physics equations, on what no additional conditions such as the integrability conditions are imposed, can possess such properties. The results of the present paper were obtained with the help of skew-symmetric differential forms. 展开更多
关键词 integrability of Mathematical Physics Equations Double Solutions integrable Structures Discrete Transitions Skew-Symmetric Differential forms
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Notes on Canonical Forms of Integrable Vector Nonlinear Schr?dinger Systems
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作者 陈奎 张大军 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期5-7,共3页
We present canonical forms of integrable vector nonlinear Sehr6dinger systems. Mathematically, it is enough to focus on these canonical forms.
关键词 NLS Notes on Canonical forms of integrable Vector Nonlinear Schr?dinger Systems
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Making Cultural Integration Work——Lessons form the Successful Air France KLM Combination
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作者 Marc Raynaud 《China's Foreign Trade》 2008年第Z3期59-61,共3页
The reccnt Alcatel Lucent failure is an example of how many mergers run into considerable implementing difficulties in the months following their launch. Despite promising perspectives,no coherent whole seems to come ... The reccnt Alcatel Lucent failure is an example of how many mergers run into considerable implementing difficulties in the months following their launch. Despite promising perspectives,no coherent whole seems to come out of the merger,just as anticipated synergies have a hard time materializing. 展开更多
关键词 Lessons form the Successful Air France KLM Combination WORK KLM Making Cultural integration Work very
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Hamiltonian Forms for a Hierarchy of Discrete Integrable Coupling Systems
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作者 XU Xi-Xiang YANG Hong-Xiang LU Rong-Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1269-1275,共7页
A semi-direct sum of two Lie algebras of four-by-four matrices is presented,and a discrete four-by-fourmatrix spectral problem is introduced.A hierarchy of discrete integrable coupling systems is derived.The obtainedi... A semi-direct sum of two Lie algebras of four-by-four matrices is presented,and a discrete four-by-fourmatrix spectral problem is introduced.A hierarchy of discrete integrable coupling systems is derived.The obtainedintegrable coupling systems are all written in their Hamiltonian forms by the discrete variational identity.Finally,we prove that the lattice equations in the obtained integrable coupling systems are all Liouville integrable discreteHamiltonian systems. 展开更多
关键词 离散可积系 广义Hamiltonian模型 可积耦合 孤子方程 理论物理学
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Integral estimates for Jacobians and components of Quasiconformal mappings
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作者 王勇 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第4期415-418,共4页
We obtain the global weighted estimates for Jacobian J(x,f)and its subdeterminants, as well as the components of K-quasiconformalmappings in L^s(μ)-averagingdomains. To develop these estimates, both local and global ... We obtain the global weighted estimates for Jacobian J(x,f)and its subdeterminants, as well as the components of K-quasiconformalmappings in L^s(μ)-averagingdomains. To develop these estimates, both local and global weighted Ponincaré inequalities for differential forms are established. 展开更多
关键词 积分估计 Jacobians行列式 准投影映射 L^p积分
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产教融合共同体建设:形态演进、现实审视与路径优化 被引量:4
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作者 汤慧芹 周斌 《中国职业技术教育》 北大核心 2024年第3期21-27,共7页
打造产教融合共同体是深化现代职业教育体系建设改革、推动产业结构调整升级、促进经济社会发展的重要途径。通过分析产教融合组织形态演进历程发现,产教融合共同体形态从初级阶段的项目合作式向着未来阶段的生态圈型共同体演进。针对... 打造产教融合共同体是深化现代职业教育体系建设改革、推动产业结构调整升级、促进经济社会发展的重要途径。通过分析产教融合组织形态演进历程发现,产教融合共同体形态从初级阶段的项目合作式向着未来阶段的生态圈型共同体演进。针对产教融合共同体建设中的现实问题,需要在加强产教融合共同体建设的政策供给和财政支持、鼓励和引导产教融合共同体的组织变革、建立高效的信息交流平台和沟通协调机制、推进实体化运行和市场化运作等方面积极行动,促进产教融合共同体的健康发展,实现建设职教强国的战略目标。 展开更多
关键词 产教融合 共同体 形态演进 现实审视 路径优化
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