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NDVI-Based Lacunarity Texture for Improving Identification of Torreya Using Object-Oriented Method 被引量:5
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作者 HAN Ning WU Jing +2 位作者 Amir Reza Shah Tahmassebi XU Hong-wei WANG Ke 《Agricultural Sciences in China》 CAS CSCD 2011年第9期1431-1444,共14页
Normalized Difference Vegetation Index (NDVI) is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the... Normalized Difference Vegetation Index (NDVI) is a very useful feature for differentiating vegetation and non-vegetation in remote sensed imagery. In the light of the function of NDVI and the spatial patterns of the vegetation landscapes, we proposed the lacunarity texture derived from NDVI to characterize the spatial patterns of vegetation landscapes concerning the "gappiness" or "emptiness" characteristics. The NDVI-based lacunarity texture was incorporated into object-oriented classification for improving the identification of vegetation categories, especially Torreya which was the targeted tree species in the present research. A three-level hierarchical network of image objects was defined and the proposed texture was integrated as potential sources of information in the rules base. A knowledge base of rules created by classifier C5.0 indicated that the texture could potentially be applied in object-oriented classification. It was found that the addition of such texture improved the identification of every vegetation category. The results demonstrated that the texture could characterize the spatial patterns of vegetation structures, which could be a promising approach for vegetation identification. 展开更多
关键词 Torreya NDVI LACUNARITY class hierarchy object-oriented method decision tree spatial pattern
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Product Family Design Methodology Using Object-Oriented Approach
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作者 WANG Ai-min, MENG Ming-chen, HUANG Jing-yuan (Department. of Precision Instruments and Mechanology, Tsinghua Univers ity, Beijing 100084, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期141-142,共2页
The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m a... The serious competition environment of global marke t requests the enterprise to change traditional product development strategy and a dopt new theory in order to meet diverse customer needs while maintaining near m ass production efficiency, which is the main philosophy of mass customization. P roduct family design is research focus at present and also is the core technolog y of DFMC (design for mass customization). Firstly, this paper explores the fund amental issues of product family, such as concepts of modularity, commonality/di versity, product platform and product family architecture etc. We compare the te rminology between product family and object-oriented approach in the next step. Thirdly, this paper puts forwards one product family design methodology based o n product platform and under different phase of product life cycle constrains, f or example, functional, assembly and service etc. At the end section of this pap er, we applied, the object-oriented approach in above mentioned product family design methodology to realize the design process. In one word, this paper propos ed one product family design methodology based on object oriented approach and p roduct life cycle consideration, especially the conjointness of characteristic o f OOA and concepts of product family. The main property of OOA are encapsulation , inherence and polymorphism. Encapsulation can represent the module or building blocks of product family. Inherence can be extended to describe the modularity and commonality, and also be used to construct variant space. Alternative specif ic of product family architecture can be embodied with polymorphism. And fin aly, we give the future work contents. In order to derive the product platform a nd achieve modularity and commonality/diversity, interface management between bu ilding block is necessary. The question is how the OOA can be applied in interfa ce management to get our aim OOA is the basis of many information management sy stem, then the question is how to build one system to manage the information of product family and support mass customization The third question is how to deve lop one computer aided tool to facilitate the application of OOA for product fam ily design, even be used to category of design for mass customization. 展开更多
关键词 product family design product platform object- oriented approach (OOA) product life cycle
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Research on Modeling and Reusing of Computer Numerical Control Software with Object-oriented Technology 被引量:1
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作者 胡俊 王宇晗 +1 位作者 王涛 蔡建国 《Journal of Donghua University(English Edition)》 EI CAS 2001年第3期66-69,共4页
To improve the reusable and configurable ability of computer numerical control ( CNC ) software, a new method to construct reusable model of CNC software with object-oriented (OO) technology is proposed. Based on anal... To improve the reusable and configurable ability of computer numerical control ( CNC ) software, a new method to construct reusable model of CNC software with object-oriented (OO) technology is proposed. Based on analyzing function of CNC software, the article presents how to construct a general class library of CNC software with OO technology. Most function modules of CNC software can he reused because of inheritable capability of classes. Besides, the article analyzes the object relational model in request/report mode, and multitask concurrent management model, which can he applied on double-CPU hardware platform and Windows 95/NT environment. Finally, the method has been successfully applied on a turning CNC system and a milling CNC system, and some function modules have been reused. 展开更多
关键词 CNC Software object- oriented Request/Report Multitask CONCURRENT Process.
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Object-Oriented Design for FDTD Visual Scientific Computing
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作者 Dong, X. Wang, W. Wang, G. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第3期71-75,共5页
A scheme for general purposed FDTD visual scientific computing software is introduced in this paper using object-oriented design (OOD) method. By abstracting the parameters of FDTD grids to an individual class and sep... A scheme for general purposed FDTD visual scientific computing software is introduced in this paper using object-oriented design (OOD) method. By abstracting the parameters of FDTD grids to an individual class and separating from the iteration procedure, the visual software can be adapted to more comprehensive computing problems. Real-time gray degree graphic and wave curve of the results can be achieved using DirectX technique. The special difference equation and data structure in dispersive medium are considered, and the peculiarity of parameters in perfectly matched layer are also discussed. 展开更多
关键词 Computational methods Computer aided design Data structures Difference equations Finite difference method Iterative methods Natural sciences computing Object oriented programming Parameter estimation Three dimensional computer graphics Time domain analysis
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New Refinement Relations of Z Specifications for Multiple Viewpoints Oriented Requirements Method
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作者 He Yan xiang, Song Qiang, Huang Qian School of Computer, State Key Laboratory of Software Engineering Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期304-312,共9页
In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate ... In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate or correct when considering specifications that have temporal relationships of operations. The concept of temporal state variables is introduced into Z. Then new implementation relations are defined and new refinement relations are deduced, mainly for temporal state variables to process temporal relationships of operations. We use state transition systems to abstract the temporal state transitions. A simple example is used to show the procedures of MVORM. Finally some directions of further work are forwarded. 展开更多
关键词 temporal state variable formal description language state transition system implementation relation refinement relation multiple viewpoints oriented requirements method
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Two Generic Frameworks of Multiple Viewpoints Oriented Requirements Method and Their Comparison
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作者 Song Qiang, He Yan xiang, Huang Qian School of Computer Science, State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期313-319,共7页
Traditional requirements method has some problems when it is used for large distributed systems. Multiple viewpoints oriented requirements method (MVORM) is a new method for resolving these problems. This paper develo... Traditional requirements method has some problems when it is used for large distributed systems. Multiple viewpoints oriented requirements method (MVORM) is a new method for resolving these problems. This paper develops two generic formal frameworks of MVORM, framework based on refinement relation (FBRR) and framework based on implementation relation (FBIR). They are generic, because no assumptions are made about the development process or the formal description languages to be used. Three kinds of specification relations and three kinds of specification transformations are discussed over FBIR and FBRR. This paper also compares the equivalence between FBIR and FBRR. We point out that an equivalent FBIR can be found for any FBRR, but reverse transformation is not always possible. We think FBIR is better than FBRR on most cases. 展开更多
关键词 multiple viewpoints oriented requirements method framework based on refinement relation framework based on implementation relation refinement relation implementation relation
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Temperature Field Reconstruction in High-Temperature Gas by Using the Colored Background Oriented Schlieren Method
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作者 Jun Wu Haitao Xu +3 位作者 Fengcheng Song Jun Xu Yanling Li Tao Wang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第3期425-434,共10页
A 3D temperature field reconstruction method using the colored background oriented schlieren(CBOS)method is proposed to address image blurring due to the different refractive index of the multi-wavelength light and si... A 3D temperature field reconstruction method using the colored background oriented schlieren(CBOS)method is proposed to address image blurring due to the different refractive index of the multi-wavelength light and significant errors produced when the traditional background oriented schlieren(BOS)method is applied to high-temperature gas.First,the traditional method is employed to reconstruct the non-uniform 3D temperature field.Second,the CBOS method is applied to correct the distortion.Then,by analyzing the correlation coefficient among different color points of the colored background pattern,the non-uniform temperature field is reconstructed much more accurately.Finally,the experimental results are verified by applying the Runge-Kutta ray-tracing method and the thermocouple contact measurement method.The maximum average temperature error of the CBOS-reconstructed temperature field is 12.92°C,compared with the thermocouples.Therefore,an accurate three-dimensional reconstruction of the temperature field can be achieved by the proposed method effectively. 展开更多
关键词 3D temperature field reconstruction colored background oriented schlieren method ABEL inverse transform image processing
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Practical Discussion of Output Oriented Method in English Major Teaching
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作者 Yunning Zhang 《Journal of Contemporary Educational Research》 2020年第4期86-90,共5页
China’s education has always been the focus for all sectors of society,and the education reform has been going on an in-depth process.Therein English major has made good progress in teaching reform,and is the focus f... China’s education has always been the focus for all sectors of society,and the education reform has been going on an in-depth process.Therein English major has made good progress in teaching reform,and is the focus for the education sector and the public.At present,colleges and universities in our country are facing some prominent problems.They are the phenomena that many colleges and universities have always attached great importance to language education and paid not enough attention to the ability of language communication,and paid too much attention to the explanation process and lack of training.Only the overall reform and development can make the teaching effect reach a satisfactory level.By promoting students to obtain good achievements,we can carry on longterm development in the new background and new era.Output oriented method is a new word with strong timeliness.It can improve the comprehensive quality of students to a certain extent.At the same time,it can promote the teaching quality in a certain sense,and has a positive role. 展开更多
关键词 Output oriented method English major Teaching practice
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Finite Element Structural Analysis UsingObject-Oriented Techniques
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作者 张冬泉 姜继海 +1 位作者 梁迎春 孙靖民 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第2期67-71,共5页
This paper describes the object-oriented implementational method of finite element structural analysis, gives the basic concepts of the object-oriented method and objectoriented programming, develops a complete class ... This paper describes the object-oriented implementational method of finite element structural analysis, gives the basic concepts of the object-oriented method and objectoriented programming, develops a complete class hierarchy structure of object-oriented finite element structural analysis, and gives a part C+ + code description. 展开更多
关键词 object-oriented method(OOM) object-oriented programming(OOP) finite element analysis(FEA) class HIERARCHY
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OBJECT-ORIENTED FINITE ELEMENT ANALYSIS AND PROGRAMMING IN VC++
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作者 MA Yong-qi(马永其) +1 位作者 FENG Wei(冯伟) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1437-1443,共7页
The design of finite element analysis program using object-oriented programming (OOP) techniques is presented. The objects, classes and the subclasses used in the programming are explained. The system of classes libra... The design of finite element analysis program using object-oriented programming (OOP) techniques is presented. The objects, classes and the subclasses used in the programming are explained. The system of classes library of finite element analysis program and Windows-type Graphical User Interfaces by VC + + and its MFC are developed. The reliability, reusability and extensibility of program are enhanced. It is a reference to develop the large-scale, versatile and powerful systems of object-oriented finite element software. 展开更多
关键词 object-oriented programming finite element method PROGRAM design VC+ +
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A Shortcut for Extricating System Development from Predicament-by Means of Object-oriented Methods
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作者 潘启澍 安实 +1 位作者 王福胜 张宝祥 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第3期92-95,共4页
Three main problems in system development and the plight of the system development are analyzed and discussed. Finally a practical and formalized method-object-oriented method is proposed to extncate the system develo... Three main problems in system development and the plight of the system development are analyzed and discussed. Finally a practical and formalized method-object-oriented method is proposed to extncate the system development from the predicament. 展开更多
关键词 ss: object-oriented method (o-o method) RELATIONAL SYSTEM SYSTEM developing SYSTEM design
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An AI Embedded Object-Oriented Approach for Formulating Computable General Equilibrium
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作者 Li Tong (Department of Automatic Control Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China) Chen Shuheng (Department of Economics, National Chengchi University, Taipei, 11623) Feng Shan (Department of Automatic Control 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第1期14-21,共8页
This paper proposes and illustrates an AI embedded object-oriented methodology to formulate the computable general equilibrium (CGE) models. In this framework, a CGE model is viewed as a collection of objects embedd... This paper proposes and illustrates an AI embedded object-oriented methodology to formulate the computable general equilibrium (CGE) models. In this framework, a CGE model is viewed as a collection of objects embedded AI or namely agents in computer world, corresponding to economic agents and entities in real world, such as government, households, markets and so on. A frame representation of major objects in CGE model is used for trade and environment. Embedded Al object-oriented approach (or software agent) is used in the CGE model representation can able to narrow the gap among the semantic representation, formal CGE (mathematical) representation and computer and algorithm representation, and to improve CGE in understanding and maintenance etc. In such a system, constructing a CGE model to appear an intuitive process rather than an abstract process. This intuitive process needs more understanding of the substance of economics and the logic underlying the problem rather than mathematical notation. 展开更多
关键词 Computable general equilibrium Artificial intelligence object-oriented method Agents.
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Object-oriented software tools for parallel PDE solvers
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作者 Michael Thune(Uppsala University, Dept. of Scientific Computing, Box 12O, S-751 04, Uppsala, Sweden.E-mail: ndchael@tdb.uu.se) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期420-429,共10页
An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writ... An object-oriented approach is taken to the problem of formulating portable, easy-to-modify PDE solvers for realistic problems in three space dimensions. The resulting software library, Cogito, contains tools for writing programs to be executed on MIMD computers with distributed memory. Difference methods on composite, structured grids are supported. Most of the Cogito classes have been implemented in Fortran 77, in such a way that the object-oriented design is visible. With respect to parallel performance, these tools yield code that is comparable to parallel solvers written in plain Fortran 77. The resulting programs are can be executed without modification on a large number of multicomputer platforms, and also on serial computers. The uppermost level of abstraction in Cogito concerns the problem of decoupling the numerical method from the PDE problem. The validity of these tools has been preliminarily demonstrated with a C++ implementation for one-dimensional problems. 展开更多
关键词 object-oriented software tool parallel computer PDE composite grid difference method
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Concurrent Object-Oriented Programming Based on MPI
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作者 鲁宏伟 裴晓黎 +1 位作者 汪厚祥 肖永玲 《Journal of Shanghai University(English Edition)》 CAS 2004年第3期295-300,共6页
Object-oriented model possesses inherent concurrency. Integration of concurrency and object-orientation is a promising new field. MPI is a message-passing standard and has been adopted by more and more systems. This p... Object-oriented model possesses inherent concurrency. Integration of concurrency and object-orientation is a promising new field. MPI is a message-passing standard and has been adopted by more and more systems. This paper proposes a novel approach to realize concurrent object-oriented programming based on Message-passing interface(MPI) in which future method communication is adopted between concurrent objects. A state behavior set is proposed to solve inheritance anomaly, and a bounded buffer is taken as an example to illustrate this proposal. The definition of ParaMPI class, which is the most important class in the concurrent class library, and implementation issues are briefly described. 展开更多
关键词 message-passing interface object-oriented the future method inheritance anomaly concurrent class library.
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Goal-oriented error estimation applied to direct solution of steady-state analysis with frequency-domain finite element method
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作者 林治家 由小川 庄茁 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第5期539-552,共14页
Based on the concept of the constitutive relation error along with the residuals of both the origin and the dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed. It lead... Based on the concept of the constitutive relation error along with the residuals of both the origin and the dual problems, a goal-oriented error estimation method with extended degrees of freedom is developed. It leads to the high quality locM error bounds in the problem of the direct-solution steady-state dynamic analysis with a frequency-domain finite element, which involves the enrichments with plural variable basis functions. The solution of the steady-state dynamic procedure calculates the harmonic response directly in terms of the physical degrees of freedom in the model, which uses the mass, damping, and stiffness matrices of the system. A three-dimensional finite element example is carried out to illustrate the computational procedures. 展开更多
关键词 goal-oriented error estimation finite element method (FEM) direct-solutionsteady-state analysis frequency domain
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Object-Oriented Modeling of the Variation of Acceleration and Deceleration Characteristics in Relation to Speed Bands for Railway Vehicles
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作者 Hyun-Soo Jeong Jong-Young Park Hanmin Lee 《Energy and Power Engineering》 2023年第8期277-290,共14页
Automated operation and artificial intelligence technology have become essential for ensuring the safety, efficiency, and punctuality of railways, with applications such as ATO (Automatic Train Operation). In this stu... Automated operation and artificial intelligence technology have become essential for ensuring the safety, efficiency, and punctuality of railways, with applications such as ATO (Automatic Train Operation). In this study, the authors propose a method to efficiently simulate the kinematic characteristics of railroad vehicles depending on their speed zone. They utilized the function overloading function supported by a programming language and applied the fourth-order Lunge-Kutta method for dynamic simulation. By constructing an object model, the authors calculated vehicle characteristics and TPS and compared them with actual values, verifying that the developed model represents the real-life vehicle characteristics accurately. The study highlights potential improvements in automated driving and energy consumption optimization in the railway industry. 展开更多
关键词 Railway Vehicle ATO Lunge-Kutta method object-oriented Model Function Overloading
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Object-Oriented Finite Element Analysis of Metal Working Processes
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作者 Surendra Kumar 《Journal of Software Engineering and Applications》 2010年第6期572-579,共8页
Recently an object-oriented approach has been applied in the fields of finite element analysis with a view to treating the various complexities within these. It has been demonstrated that finite element software desig... Recently an object-oriented approach has been applied in the fields of finite element analysis with a view to treating the various complexities within these. It has been demonstrated that finite element software designed using an object-oriented approach can be significantly more robust than traditional codes. This paper describes a special kind of implementation of object-oriented programming which is rather hybrid in nature, in the development of a finite element code for engineering analysis of metal working problems using C++, and discusses the advantages of this approach. 展开更多
关键词 FINITE Element method Data ABSTRACTION Techniques object-oriented PROGRAMMING C++ PROGRAMMING Language METAL Working
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Behavior——oriented Teaching Method and English Curriculum Reform of Vocational Education
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作者 曾海波 《海外英语》 2017年第2期239-240,共2页
This thesis introduces the Behavior-oriented teaching method and the principles of curriculum reform in Vocational English.It mainly discusses the application of behavior oriented teaching method in the reform of Voca... This thesis introduces the Behavior-oriented teaching method and the principles of curriculum reform in Vocational English.It mainly discusses the application of behavior oriented teaching method in the reform of Vocational English Education,and refers problems and suggestions. 展开更多
关键词 Behavior-oriented teaching method Vocational English reform of education application
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Partitioning characteristics of gas channel of coal-rock mass in mining space and gas orientation method 被引量:8
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作者 Zhao Zhiqiang Ma Nianjie +1 位作者 Jia Housheng Cheng Yuanping 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期873-877,共5页
In order to research the influence of coal-rock mass morphology of mining space on the flow law of gas,the laboratory physical model and numerical computation methods were adopted to simulate coal mining activities.Th... In order to research the influence of coal-rock mass morphology of mining space on the flow law of gas,the laboratory physical model and numerical computation methods were adopted to simulate coal mining activities.The simulation results indicate that,after coal seam mining,the loose rock accumulation body of free caving,ordered rock arrangement body of plate damage rich in longitudinal and transverse fractures and horizontal fissure body formed by rock mass deformation imbalance are formed from bottom to top in the mining space.For these three types of accumulation bodies,there are essential differences in the accumulation state,rock size and gas breakover characteristics.According to this,the coal-rock mass in the mining space is classified into gas turbulence channel area,gas transitional flow channel area and gas seepage channel area.In the turbulence channel area,the gas is distributed transversely and longitudinally and gas diffuses in the form of convection with Reynolds number R_e more than100;in the transitional flow channel area,one-way or two-way gas channels are crisscross and gas is of transitional flow regime with R,.between 10 and 100.In the seepage channel area,there are a few vertical gas channels with R,.less than 10.In this paper,the researches on the gas orientation method in different partitions were further carried out,gas orientation methods of low-level pipe burying,middle-level interception and high-level extraction were determined and an on-site industrial test was conducted,achieving the effective diversion of gas and verifying the reasonableness of gas channel partition. 展开更多
关键词 Gas channel Partitioning characteristics Gas flow regime Gas orientation method
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Stator-Flux Oriented Continuous Control of Torque in Induction Motors 被引量:4
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作者 Hong-ming Xie Yi Ruan Bo-shi Chen 《Advances in Manufacturing》 2000年第1期49-53,共5页
This paper analyzes dynamic equivalent circuit of induction motor and the relationship among inner fluxes, then presents a direct stator flux oriented continuous torque control (DSFOCTC) scheme of induction motor , wh... This paper analyzes dynamic equivalent circuit of induction motor and the relationship among inner fluxes, then presents a direct stator flux oriented continuous torque control (DSFOCTC) scheme of induction motor , which uses stator current vector control instead of voltage vector control. As a combination of direct torque control (DTC) and flux oriented vector control, it achieves round stator flux and continuous dynamic torque control resulting in less torque ripple than that in DTC. It reduces the dependence on rotor parameters, and is especially insensitive to rotor resistance. Finally, an induction motor speed control system incorporating this novel scheme is given and checked by simulation. 展开更多
关键词 flux accelerate method stator flux oriented rotor flux oriented DTC
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