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Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils
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作者 Belemdara Dingamadji Hilaire Mbaïnaïbeye Jérôme Guidkaya Golam 《Journal of Electromagnetic Analysis and Applications》 2024年第2期11-23,共13页
The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the tw... The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet. 展开更多
关键词 MODELLING 3D Finite Elements Magnetic Flux Hybrid stepping Motor
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ROBUST ADAPTIVE CONTROL SCHEME FOR IMPROVING LOW-SPEED PROFILE TRACKING PERFORMANCE OF HYBRID STEPPING MOTOR SERVO DRIVE 被引量:3
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作者 陈卫东 容启亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第1期8-16,共9页
A robust adaptive control approach is presented to improve the performance of the control scheme proposed in the authors' previous work, aiming at producing a low ripple hybrid stepping motor servo drive for precisio... A robust adaptive control approach is presented to improve the performance of the control scheme proposed in the authors' previous work, aiming at producing a low ripple hybrid stepping motor servo drive for precision profile tracking at a low speed. In order to construct a completely integrated control design philosophy to reduce torque ripple and at the same time to enhance tracking performance, the properties of nonlinear uncertainties in the system dynamics are uncovered, and then incorporated into the design of the controller. The system uncertainties concerned with ripple dynamics and other external disturbances are composed of two categories. The first category of uncertainties with linear parameterization arising from the detention effect is dealt with by the wellknown adaptive control method. A robust adaptive method is used to deal with the second category of uncertainties resulting from the non-sinusoidal flux distribution. The μ-modification scheme is used to cease parameter adaptation by the robust adaptive control law, thus ensuring that the trajectory tracking error asymptotically converges to a pre-specified boundary. Experiments are performed with a typical hybrid stepping motor to test its profile tracking accuracy. Results confirm the proposed control scheme. 展开更多
关键词 robust adaptive control tracking control stepping motor torque ripple
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A Proper Time Integration with Split Stepping for the Explicit Free-Surface Modeling 被引量:2
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作者 周伟东 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第2期255-265,共11页
Errors due to split time stepping are discussed for an explicit free–surface ocean model. In commonly used split time stepping, the way of time integration for the barotropic momentum equation is not compatible with ... Errors due to split time stepping are discussed for an explicit free–surface ocean model. In commonly used split time stepping, the way of time integration for the barotropic momentum equation is not compatible with that of the baroclinic one. The baroclinic equation has three–time–level structure because of leapfrog scheme. The barotropic one, however, has two–time–level structure when represented in terms of the baroclinic time level, on which the baroclinic one is integrated. This incompatibility results in the splitting errors as shown in this paper. The proper split time stepping is therefore proposed in such a way that the compatibility is kept between the barotropic and baroclinic equations. Its splitting errors are shown extremely small, so that it is particularly relevant to long–term integration for climate studies. It is applied to a free–surface model for the North Pacific Ocean. 展开更多
关键词 Free–surface model Split time stepping Split error Leapfrog scheme
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Linear Piezoelectric Stepping Motor with Broad Operating Frequency 被引量:2
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作者 陈西府 王寅 +1 位作者 孙梦馨 黄卫清 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第2期137-142,共6页
The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displac... The existing resonant linear piezoelectric motors must operate with high working voltage in resonant condition,resulting in their narrow operating frequency range and poor running stability.Here,with the large displacement output characteristics of piezoelectric stacks,the trajectory at the drive foot of stator is firstly produced with two space quadrature piezoelectric actuators excited by sawtooth wave and square wave.Secondly,the friction drive principle of motor is used to analyze the working mechanisms of the continuous stepping motion.Finally,the motor prototype is designed and experiments are carried out.The experimental result shows that the motor can stably operate within the scope of 350 Hz to 750 Hz.When the excitation voltage is 30 Vand pre-load is 3Nor10 N,the lateral amplitude of the drive foot is approximately 4μm and the stable average interval ranges from3.1μm to 3.2μm with the error rate of 5%—7.5%. 展开更多
关键词 linear motor piezoelectric stack stepping motor broad operating frequency
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The Stepping Motion of Brownian Particle Derived by Nonequilibrium Fluctuation 被引量:2
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作者 ZHANYong ZHAOTong-Jun YUHui SONGYan-Li ANHai-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第6期653-656,共4页
The direct motion of Brownian particle is considered as a result of system derived by external nonequilibriumfluctuating. The cooperative effects caused by asymmetric ratchet potential, external rocking force and addi... The direct motion of Brownian particle is considered as a result of system derived by external nonequilibriumfluctuating. The cooperative effects caused by asymmetric ratchet potential, external rocking force and additive colorednoise drive a Brownian particle in the directed stepping motion. This provides this kind of motion of kinesin along amicrotubule observed in experiments with a reasonable explanation. 展开更多
关键词 stepping motion nonequilibrium fluctuation KINESIN
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Splitting Based Scheme for Three-dimensional MHD with Dual Time Stepping 被引量:1
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作者 FU Huazheng FENG Xueshang 《空间科学学报》 CAS CSCD 北大核心 2015年第1期9-17,共9页
A new hybrid numerical scheme of combining an E-CUSP(Energy-Convective Upwind and Split Pressure) method for the fluid part and the Constrained Transport(CT) for the magnetic induction part is proposed.In order to avo... A new hybrid numerical scheme of combining an E-CUSP(Energy-Convective Upwind and Split Pressure) method for the fluid part and the Constrained Transport(CT) for the magnetic induction part is proposed.In order to avoid the occurrence of negative pressure in the reconstructed profiles and its updated value,a positivity preserving method is provided.Furthermore,the MHD equations are solved at each physical time step by advancing in pseudo time.The use of dual time stepping is beneficial in the computation since the use of dual time stepping allows the physical time step not to be limited by the corresponding values in the smallest cell and to be selected based on the numerical accuracy criterion.This newly established hybrid scheme combined with positivity preserving method and dual time technique has demonstrated the accurateness and robustness through numerical experiments of benchmark problems such as the 2D Orszag-Tang vortex problem and the3 D shock-cloud interaction problem. 展开更多
关键词 SPLITTING BASED SCHEME THREE-DIMENSIONAL MHD Dual time stepping
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Distributed Stepping Motor Control System 被引量:1
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作者 Bai Jie, Chen Zhiqiang, Xiao Guoqing, Zhan Wenlong, Guo Zhongyan, Wang Meng, Sun Zhiyu Li Jiaxing, Tian Wendong, Wang Jiansong, Wang Wusheng, Mao Ruishi, Chen Zhiqiang Hu Zhcngguo, Chen Lixin and Li Ch 《IMP & HIRFL Annual Report》 2001年第1期100-100,共1页
The beam diagnostic devices used at RIBLL are driven by stepper motors, which are controlled by I/O modules based on ISA-bus in an industrial computer. The disadvantages of such mode are that a large number of long ca... The beam diagnostic devices used at RIBLL are driven by stepper motors, which are controlled by I/O modules based on ISA-bus in an industrial computer. The disadvantages of such mode are that a large number of long cables are used and one computer to control is unsafe. We have developed a distributed stepping motor control system for the remote, local and centralized control of the stepping motors. RS-485 bus is used for the connection between the remote control unit and the local control units. The con... 展开更多
关键词 disadvantages stepping CENTRALIZED contr STEPS DIAGNOSTIC ABSOLUTE switches panel START
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The Stable Explicit Time Stepping Analysis with a New Enrichment Scheme by XFEM
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作者 Xue-cong Liu Qing Zhang Xiao-zhou Xia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2017年第4期411-427,共17页
This paper focuses on the study of the stability of explicit time integration algorithm for dynamic problem by the Extended Finite Element Method(XFEM).A new enrichment scheme of crack tip is proposed within the frame... This paper focuses on the study of the stability of explicit time integration algorithm for dynamic problem by the Extended Finite Element Method(XFEM).A new enrichment scheme of crack tip is proposed within the framework of XFEM.Then the governing equations are derived and evolved into the discretized form.For dynamic problem,the lumped mass and the explicit time algorithm are applied.With different grid densities and different forms of Newmark scheme,the Dynamic Stress Intensity Factor(DSIF)is computed by using interaction integral approach to reflect the dynamic response.The effectiveness of the proposed scheme is demonstrated through the numerical examples,and the critical time stepping in different situations are listed and analyzed to illustrate the factors that affect stability. 展开更多
关键词 XFEM DSIF NEWMARK SCHEME time stepping stability
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TIME ACCURATE 2D NAVIER-STOKES CALCULATIONS WITH A DUAL-TIME STEPPING METHOD
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作者 Yang Yong, Qiao Zhide (Faculty 503, Northwestern Polytechnical University, Xi′an, 710072, China) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1997年第3期9-14,共6页
With the cell vertex finite volume discretization in space and second order backward implicit discretization in time, 2D unsteady Navier Stokes equations are solved by a dual time stepping method to simulate compr... With the cell vertex finite volume discretization in space and second order backward implicit discretization in time, 2D unsteady Navier Stokes equations are solved by a dual time stepping method to simulate compressible viscous flow around rigid airfoils in arbitrary unsteady motion. The selection of physical time step is not restricted by stability condition any more, and most of the successful acceleration techniques used in steady calculations can be implemented to increase the computation efficiency. 展开更多
关键词 two dimensional flow unsteady flow Navier Stokes equation viscous flow implicit discretization dual time stepping
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MINIMUN TIME OPTIMAL CONTROL OF STEPPING MOTOR
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作者 Luo An(College of Information Engineering, Central South University of Technology, Changsha, 410083, China) 《Journal of Central South University》 SCIE EI CAS 1995年第2期54-58,共5页
The paper describes a new method of the stepping motor moimun time optimal control with closed-loop control. A mathematical model and optimal control strategy for the optimal control of stepping motor are proposed. ... The paper describes a new method of the stepping motor moimun time optimal control with closed-loop control. A mathematical model and optimal control strategy for the optimal control of stepping motor are proposed. Realizing technology for accelerating 展开更多
关键词 OPTIMAL CONTROL stepping MOTOR MICROCOMPUTER
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Sliding state stepping algorithm for solving impact problems of multi-rigid-body system with joint friction
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作者 姚文莉 陈滨 +1 位作者 刘才山 徐鉴 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第12期1621-1627,共7页
Impact dynamics of multi-rigid-body systems with joint friction is considered. Based on the traditional approximate assumption dealing with impact problem, a general numerical method called the sliding state stepping ... Impact dynamics of multi-rigid-body systems with joint friction is considered. Based on the traditional approximate assumption dealing with impact problem, a general numerical method called the sliding state stepping algorithm is introduced. This method can avoid difficulties in solving differential equations with variable scale and its result can avoid energy inconsistency before and after impact from considering complexily of tangential sliding mode. An example is given to describe details using this algorithm. 展开更多
关键词 multi-rigid-body system joint friction sliding state stepping algorithm
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Static-torque Characteristics of Three-phase Hybrid(HB) Stepping Motors and Influence of Way of Winding Connection on Operating Characteristics of Motors of This Kind
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作者 刘宝廷 郑萍 崔淑梅 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第4期59-62,共4页
The paper presents the static-torque characteristics of three-phase hybrid stepping motors and discusses the influence of way of winding connection on operating characteristics of motors of this kind.
关键词 stepping motors TORQUE CHARACTERISTICS WINDING CONNECTION
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The Stable Explicit Time Stepping Analysis with a New Enrichment Scheme by XFEM
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作者 Xue-cong Liu Qing Zhang Xiao-zhou Xia 《Computers, Materials & Continua》 SCIE EI 2017年第3期187-206,共20页
This paper focuses on the study of the stability of explicit time integration algorithm for dynamic problem by the Extended Finite Element Method(XFEM).A new enrichment scheme of crack tip is proposed within the frame... This paper focuses on the study of the stability of explicit time integration algorithm for dynamic problem by the Extended Finite Element Method(XFEM).A new enrichment scheme of crack tip is proposed within the framework of XFEM.Then the governing equations are derived and evolved into the discretized form.For dynamic problem,the lumped mass and the explicit time algorithm are applied.With different grid densities and different forms of Newmark scheme,the Dynamic Stress Intensity Factor(DSIF)is computed by using interaction integral approach to reflect the dynamic response.The effectiveness of the proposed scheme is demonstrated through the numerical examples,and the critical time stepping in different situations are listed and analyzed to illustrate the factors that affect the numerical stability. 展开更多
关键词 XFEM DSIF Newmark scheme time stepping stability
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A hybrid stepping motor system with dual CPU
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作者 高晗璎 赵克 孙力 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第4期382-386,共5页
An indirect method of measuring the rotor position based on the magnetic reluctance variation is presented in the paper. A single-chip microprocessor 80C196KC is utilized to compensate the phase shift produced by the ... An indirect method of measuring the rotor position based on the magnetic reluctance variation is presented in the paper. A single-chip microprocessor 80C196KC is utilized to compensate the phase shift produced by the process of position signals. At the same time, a DSP (Data Signal Processor) unit is used to realize the speed and current closed-loops of the hybrid stepping motor system. At last, experimental results show the control system has excellent static and dynamic characteristics. 展开更多
关键词 closed-loop control indirect measurement hybrid stepping motor
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Stepping through a new door in La Porte IN
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作者 Lan T. Nguyen Timothy Yee Thach Nguyen 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2007年第3期174-,共1页
  In this issue of the Journal of Geriatric Cardiology,Yang et al.1 studied the effects of arotinolol, a beta-blocker (BB), on the right ventricular (RV) function.……
关键词 stepping through a new door in La Porte IN LA
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Finite Element Methods Applied to the Tubular Linear Stepping Motor
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作者 Walid El Fezzani Abdessattar Ben Amor 《Journal of Electromagnetic Analysis and Applications》 2013年第5期219-222,共4页
In this paper proposes a Finite Element Methods analyzing applied to the linear tubular stepping actuator. The linear displacement is modeled by means of a layer of finite elements placed in the air gap. The design of... In this paper proposes a Finite Element Methods analyzing applied to the linear tubular stepping actuator. The linear displacement is modeled by means of a layer of finite elements placed in the air gap. The design of the linear stepper motor for achieving a specific performance requires the choice of appropriate tooth geometry. The magnetic field of the actuator has been analyzed using the finite element method over a current-displacement variation. The magneto static field and electromagnetic force was introduced in order to predict before construction, the inductance values according to the displacement and the currents into the coils. The results were obtained for the magnetic flux density distribution and the electromagnetic force for different positions and current. 展开更多
关键词 FINITE Element Methods Linear TUBULAR stepping ACTUATOR MESH Repartition
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Detonator stepping stress acceleration life test
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作者 郑波 张红星 王波 《Journal of Measurement Science and Instrumentation》 CAS 2013年第2期139-141,共3页
Through the failure mechanism analysi s and simulation test of a certain kind of detonator,this paper confirms the str ess level of the stepping stress acceleration life test of the detonator,and t hen e stablishes th... Through the failure mechanism analysi s and simulation test of a certain kind of detonator,this paper confirms the str ess level of the stepping stress acceleration life test of the detonator,and t hen e stablishes the data processing mathematical model and storage life forecasting m ethod.At last,according to the result of the stepping stress acceleration lif e test of the detonator,this paper forecasts the reliable storage life of the detonator under the normal stress level. 展开更多
关键词 DETONATOR stepping stress acceleration life test storage life forecast
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Evaluating the effects of open/closed eyes and age-related differences on center of foot pressure sway during stepping at a set tempo
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作者 Hiroki Aoki Shinichi Demura +4 位作者 Haruka Kawabata Hiroki Sugiura Yu Uchida Ning Xu Hitoshi Murase 《Advances in Aging Research》 2012年第3期72-77,共6页
This study aimed to examine the effects of open/ closed eyes and age difference on Center of Foot Pressure (COP) sway during stepping. The subjects were 87 healthy males aged 10 - 80 years. COP was measured 20 times w... This study aimed to examine the effects of open/ closed eyes and age difference on Center of Foot Pressure (COP) sway during stepping. The subjects were 87 healthy males aged 10 - 80 years. COP was measured 20 times when subjects stepped on two force plates (left and right) at a rate of 60 steps/min. The evaluation parameters selected were: total trace length, velocity, circumference, rectangular area,left-right width, and front-back width. The former four of these parameters were found to be significantly lower with eyes open than eyes closed in 80-year-old subjects, while the last parameter was significantly lower with eyes open in 10-year-old subjects. In 70- and 80-year-old subjects with eyes open, circumference was greater than that in 10- and 40 - 60-year-old subjects;their rectangular area was greater than that in 50- and 60-year-old subjects;and, their front-back width was greater than that in 10- and 30 - 60-year-old subjects. With eyes closed, circumference, rectangular area, left-right width, and front-back width in 80-year- old subjects, were greater than those in 10 - 70- year-old subjects. The front-back width during stepping with eyes closed was greater in 70- and 80-year-old subjects than in 30 - 50-year-old subjects. The Romberg quotient for all COP sway parameters revealed no significant age-related differences. From our findings, a difference in body sway was observed in 80-year-old subjects (with eyes open/closed) when compared with the other age groups. In addition, the extent of sway varied little among 80 year-old- subjects have greater body sway during stepping, particularly with eyes closed. 展开更多
关键词 Elderly Dynamic Balance TEMPO stepping CENTER of FOOT Pressure (COP)
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Numerical Modeling of the Coupled Electromagnetic and Mechanical Phenomena of Linear Stepping Motors
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作者 Mustapha Zaouia Nacereddine Benamrouche M'hemed Rachek 《Journal of Electromagnetic Analysis and Applications》 2012年第1期1-8,共8页
In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepp... In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepping Motor (LSRSM). After the resolution of the non-linear electromagnetic equation governing the behaviour of the different materials of the motor using the nodal-based finite element method, this equation is then coupled to the mechanical equation firstly through the magnetic force computed by Maxwell stress tensor, and secondly by the modified flux distribution due to the moving part. Because of the precision required in the mobile part displacement and the very small air gap of stepping motors, the simulation of the movement is assured by the Macro-Element (ME) technique compared to other movement techniques that present many disadvantages. The validity of the developed model is verified through the comparison of the computed displacement of the LSRSM moving part with those given experimentally [2]. The Results shows satisfactory agreement. The obtained dynamic characteristics, particularly the starting magnetic force, are obtained by considering two values of the supplying currents. 展开更多
关键词 NUMERICAL Modeling Electromagnetic-Mechanical PHENOMENA Finite Element MOVEMENT stepping Motors
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Can the Stepping Stone Enhance the Establishment, Competition and Distribution of Sown Grassland Species during Recovery on Ex-Arable Lands?
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作者 Jimmy Edgar Alvarez-Diaz María del Carmen Santa-Regina Ignacio Santa-Regina 《Open Journal of Ecology》 2016年第10期579-597,共19页
Most diversity restoration projects are not to improve diversity per se, but rather to enhance the presence and abundance of species that are characteristic of reference or target community. The use of Bromus inermis ... Most diversity restoration projects are not to improve diversity per se, but rather to enhance the presence and abundance of species that are characteristic of reference or target community. The use of Bromus inermis suppresses annual noxious grasses and increases the control of other-forb group these species are also noxious weeds;these may be substituted with another perennial species of the same functional group all through the whole experimental period, as it occurs with other perennial-forb Carduus tenuifolius. A field experiment was conducted on abandoned arable land with sown low and high diversity treatments and natural colonization following typical farming practice for the site. Experimental plots were installed on former agricultural land that had been cropped with (a rotation of) monocultures until the end of 1995. The experiment was organized according to a block design with five replicate blocks. An opposite trend was performed among the colonizer species, because the colonizer grasses were relegated by the high dominance of sown grasses. But at the same time, the sown grasses facilitated the dominance of other colonizer-forbs species;therefore its functional replacement in the community due to sown effect was again tested. However, in natural conditions the other-forbs group was the dominant group, without taking into account the stepping-stone treatment and there was also a functional change of dominance. Our study has demonstrated the restoration effectiveness of species richness at abandoned arable land and may be enhanced by sowing late successional species. 展开更多
关键词 Colonizer Species Ecosystem Functioning INVASIVENESS Noxious Weeds RESTORATION Sowing Experiment Species Richness stepping Stone
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