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Numerical simulation and optimization of process parameters in fineblanking process 被引量:1
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作者 庄新村 赵震 +2 位作者 谢晓龙 虞松 李从心 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期514-518,共5页
Fineblanking process is a typical large localized plastic deformation process. Based on its forming characteristics, a numerical model is established and an elasto-plastic simulation is performed using the finite elem... Fineblanking process is a typical large localized plastic deformation process. Based on its forming characteristics, a numerical model is established and an elasto-plastic simulation is performed using the finite element method (FEM). The re-meshing method is used when the severe element distortion occurs to facilitate further computation and avoid divergence. The McClintock fracture criterion is adopted to predict and determine the time and site of crack initiation and propagation. Based on this numerical model, the distribution and developing trend of the stress and strain in the shearing zone are predicted. Furthermore, the influence of several process parameters, such as punch-die clearance, edge radius of punch and die, V-ring force, counter force, etc., on the blanked quality is analyzed. The discipline is in accordance with the actual manufacture situation, which can be a guidance to optimization of process parameters. 展开更多
关键词 metal forming fineblanking ductile damage ductile fracture finite element method
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Dynamic analysis of pavement on long span steel bridge decks 被引量:7
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作者 刘云 钱振东 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期212-215,共4页
In order to analyze the dynamic response of pavement on long-span steel bridge decks under random dynamic loads, the irregularities of the pavement surface is simulated with the power spectrum density function, and th... In order to analyze the dynamic response of pavement on long-span steel bridge decks under random dynamic loads, the irregularities of the pavement surface is simulated with the power spectrum density function, and the random load is calculated according to a vehicle vibration equation of vehicle model. The mechanical responses of three different cases are compared by using a transient dynamic analysis method, i. e., under random dynamic load, constant moving load and dead load respectively. The results indicate that the mid-span of two adjacent transversal diaphragms is the worst load position. The maximum vertical displacement and the maximum transversal tensile stress of the pavement are 1.33 times and 1.39 times as much as those when only considering the impact coefficients. This study not only provides a theoretical basis for the mixture design and structural design of pavement, but also puts forward higher demand on the construction and maintenance for steel deck pavement. 展开更多
关键词 steel deck pavement finite element method dynamic analysis impact coefficient
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Springback prediction of TC4 titanium alloy V-bending under hot stamping condition 被引量:5
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作者 YANG Xiao-ming DANG Li-ming +2 位作者 WANG Yao-qi ZHOU Jing WANG Bao-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第9期2578-2591,共14页
In this paper,the springback of TC4 titanium alloy under hot stamping condition was studied by means of experiment and numerical analysis.Firstly,an analytical model was established to predict the V-shaped springback ... In this paper,the springback of TC4 titanium alloy under hot stamping condition was studied by means of experiment and numerical analysis.Firstly,an analytical model was established to predict the V-shaped springback angleΔαunder the stretch-bending conditions.The model took into account of blank holder force,friction,property of the material,thickness of the sheet and the neutral layer shift.Then,the influence of several process parameters on springback was studied by experiment and finite element simulation using a V-shaped stamping tool.In the hot stamping tests,the titanium alloy sheet fractured seriously at room temperature.The titanium alloy has good formability when the initial temperature of the sheet is 750–900°C.However,the springback angle of formed parts is large and decreases with increasing temperature.The springback angleΔαdecreased by 50%from 0.5°to 0.25°,and the angleΔβdecreased by 46.7%from 1.5°to 0.8°when the initial temperature of sheet increased from 750°C to 900°C.The springback angle of titanium alloy sheet increases gradually with the increase of the punch radius,because of the increase of elastic recovery,the complex distribution of stress,the length of forming region and the decreasing degree of stress.Compared with the simulation results,the analytical model can better predict the springback angleΔα. 展开更多
关键词 titanium alloy hot stamping SPRINGBACK FE modelling analytical model
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Numerical study of RC beams under various loading rates with LS-DYNA 被引量:1
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作者 Leila MAJIDI Nima USEFI Reza ABBASNIA 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第5期1226-1239,共14页
Having an accurate understanding of concrete behavior under effects of high strain rate loading with the aim of reducing incurred damages is of great importance. Due to complexities and high costs of experimental rese... Having an accurate understanding of concrete behavior under effects of high strain rate loading with the aim of reducing incurred damages is of great importance. Due to complexities and high costs of experimental research, numerical studies can be an appropriate alternative for experimental methods. Therefore, in this research capability of the finite element method for predicting concrete behavior at various loading conditions is evaluated by LS-DYNA software. First, the proposed method is presented and then is validated in three stages under different conditions. Results of load-lnidspan displacement showed good agreement between experimental and finite element results. Capability of finite element method in analyses of beams under various rates of loading was also validated by low error of the results. In addition, the proposed method has reasonable ability to evaluate reinforced concrete beams under various loading rates and different conditions. 展开更多
关键词 strain rate dynamic loading RC beam impact loading finite element LS-DYNA
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An analytical model for predicting sheet springback after V-bending 被引量:8
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作者 ZHANG Dong-juan CUI Zhen-shan +1 位作者 CHEN Zhi-ying RUAN Xue-yu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第2期237-244,共8页
Springback is caused by the redistribution of stress in sheet material after the tooling is removed. Precise prediction of sheet springback is very important in die design. Based on Hill’s yielding criterion and plan... Springback is caused by the redistribution of stress in sheet material after the tooling is removed. Precise prediction of sheet springback is very important in die design. Based on Hill’s yielding criterion and plane strain condition, an analytical model is proposed in this paper which takes into account the effects of contact pressure, the length of bending arm between the punch and die, transverse stress, neutral surface shifting and sheet thickness thinning on the sheet springback of V-bending. The predicted results by this analytical model indicated that the contact pressure and transverse stress have much effect on the springback when the bending ratio (the ratio of punch radius to sheet thickness) is less than five. The contact pressure declined when the length of bending arm goes up, which means that shorter length of bending arm will result in larger springback. The effect of neutral surface shifting on the springback is less than that of contact pressure and decreases with the bending ratio. However, this research showed that the influence of thickness thinning on the springback can be ignored. Comparison with finite element method (FEM) simu-lating results shows that the predicted results by the analytical model accord well with simulation results by FEM. In addition to that, the bending ability—the limit bending ratio for a given sheet thickness and material properties was also determined. 展开更多
关键词 SPRINGBACK V-bending Contact pressure Neutral surface shifting Transverse stress Bending ratio
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An effective discrete artificial bee colony algorithm for flow shop scheduling problem with intermediate buffers 被引量:3
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作者 张素君 顾幸生 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3471-3484,共14页
An effective discrete artificial bee colony(DABC) algorithm is proposed for the flow shop scheduling problem with intermediate buffers(IBFSP) in order to minimize the maximum completion time(i.e makespan). The effecti... An effective discrete artificial bee colony(DABC) algorithm is proposed for the flow shop scheduling problem with intermediate buffers(IBFSP) in order to minimize the maximum completion time(i.e makespan). The effective combination of the insertion and swap operator is applied to producing neighborhood individual at the employed bee phase. The tournament selection is adopted to avoid falling into local optima, while, the optimized insert operator embeds in onlooker bee phase for further searching the neighborhood solution to enhance the local search ability of algorithm. The tournament selection with size 2 is again applied and a better selected solution will be performed destruction and construction of iterated greedy(IG) algorithm, and then the result replaces the worse one. Simulation results show that our algorithm has a better performance compared with the HDDE and CHS which were proposed recently. It provides the better known solutions for the makespan criterion to flow shop scheduling problem with limited buffers for the Car benchmark by Carlier and Rec benchmark by Reeves. The convergence curves show that the algorithm not only has faster convergence speed but also has better convergence value. 展开更多
关键词 discrete artificial bee colony algorithm flow shop scheduling problem with intermediate buffers destruction and construction tournament selection
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AN ITERATIVE ALGORITHM FOR OPTIMAL DESIGN OF NON-FREQUENCY-SELECTIVE FIR DIGITAL FILTERS 被引量:1
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作者 Tian Xinguang Duan Miyi +1 位作者 Sun Chunlai Liu Xin 《Journal of Electronics(China)》 2008年第5期667-672,共6页
This paper proposes a novel iterative algorithm for optimal design of non-frequency-selective Finite Impulse Response(FIR) digital filters based on the windowing method.Different from the traditional optimization conc... This paper proposes a novel iterative algorithm for optimal design of non-frequency-selective Finite Impulse Response(FIR) digital filters based on the windowing method.Different from the traditional optimization concept of adjusting the window or the filter order in the windowing design of an FIR digital filter,the key idea of the algorithm is minimizing the approximation error by succes-sively modifying the design result through an iterative procedure under the condition of a fixed window length.In the iterative procedure,the known deviation of the designed frequency response in each iteration from the ideal frequency response is used as a reference for the next iteration.Because the approximation error can be specified variably,the algorithm is applicable for the design of FIR digital filters with different technical requirements in the frequency domain.A design example is employed to illustrate the efficiency of the algorithm. 展开更多
关键词 Finite Impulse Response (FIR) digital filters Optimal design Windowing method Approximation error Iterative algorithm
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Numerical simulation for sheet metal forming process of 16Mn blade of large concrete-mixer truck 被引量:1
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作者 王锦红 夏伟 +2 位作者 周照耀 陈维平 郧建国 《Journal of Central South University of Technology》 2005年第1期83-87,共5页
A finite element analysis method was used to simulate the stamping process of the blade of a large concrete-mixer truck. The updated Lagrange method and the elasto-plastic constitutive equation were adopted to solve t... A finite element analysis method was used to simulate the stamping process of the blade of a large concrete-mixer truck. The updated Lagrange method and the elasto-plastic constitutive equation were adopted to solve the large strain and displacement deformation of the blade. A modified Coulomb friction model was used to solve the sliding contact between the blade and the dies. The von Mises stress distribution in the blade, the spatial displacement variation and the spring-back of the typical node were investigated in the simulation. The von Mises stress in the blade where the spring-back occurs is lowered from 463.0MPa to 150.0MPa before and after the spring-back. A typical node in the blade has a 3.33mm spring-back in Z direction. The results of the (experiments) agree well with the simulation. The analysis results are valuable for designing optimal tool dies. 展开更多
关键词 finite element simulation SPRING-BACK stamping process concrete-mixer truck BLADE
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Prediction of crack location and propagation in stretch flanging process of aluminum alloy AA-5052 sheet using FEM simulation 被引量:2
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作者 Y.DEWANG M.S.HORA S.K.PANTHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2308-2320,共13页
The stretch flanging process is significantly affected by various geometrical,material and process parameters.The punch-die clearance and initial flange length are main parameters which have major effects on the edge ... The stretch flanging process is significantly affected by various geometrical,material and process parameters.The punch-die clearance and initial flange length are main parameters which have major effects on the edge crack location and strain distribution along die profile radius in the flange.Non-axisymmetric stretch flanging process of AA-5052 sheet metal blanks was carried out by numerical simulation to predict the deformation behavior of flange,location and propagation of crack in flange and to investigate the effect of punch die clearance,flange length,die and punch profile radius and friction in the stretch flanging process.The experimental investigations were made to validate the simulations results.The results reveal that the crack length increases with the increase in the flange length.It is found that the flange length has a significant effect in circumferential direction as compared with the radial direction.The punch die clearance has the most significant effect in crack propagation in comparison with flange length.The circumferential strain is found to be larger in the case of punch having the profile radius less than the die profile radius,which leads to faster edge crack propagation.A close agreement is found between simulation and experimental results in terms of location of edge crack and forming load. 展开更多
关键词 stretch flanging process finite element simulation punch-die clearance initial flange length edge crack
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SAR IMAGE ENHANCEMENT BASED ON BEAM SHARPENING TECHNIQUE
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作者 LIYong ZI-IANGKun-hui +1 位作者 ZHUDai-yin ZHUZhao-da 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第2期147-151,共5页
A major problem encountered in enhancing SAR image is the total loss of phase information and the unknown parameters of imaging system. The beam sharpening technique, combined with synthetic aperture radiation pattern... A major problem encountered in enhancing SAR image is the total loss of phase information and the unknown parameters of imaging system. The beam sharpening technique, combined with synthetic aperture radiation pattern estimation provides an approach to process this kind of data to achieve higher apparent resolution. Based on the criterion of minimizing the expected quadratic estimation error, an optimum FIR filter with a symmetrical structure is designed whose coefficients depend on the azimuth response of local isolated prominent points because this response can be approximately regarded as the synthetic aperture radiation pattern of the imaging system. The point target simulation shows that the angular resolution is improved by a ratio of almost two to one. The processing results of a live SAR image demonstrate the validity of the method. 展开更多
关键词 synthetic aperture radar (SAR) image enhancement beam sharpening
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Simulation and experimental study of 7A09 aluminum alloy milling under double liquid quenching 被引量:1
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作者 LUO Heng WANG You-qiang ZHANG Ping 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期372-380,共9页
To explore the influence of double liquid quenching on the cutting performance of the 7A09 aluminum alloy,quasi-static compression and dynamic impact tests were carried out on the 7A09 aluminum alloy after double liqu... To explore the influence of double liquid quenching on the cutting performance of the 7A09 aluminum alloy,quasi-static compression and dynamic impact tests were carried out on the 7A09 aluminum alloy after double liquid quenching using an MTS810.23 universal testing machine and split-Hopkinson pressure bar(SHPB).The experimental data were fitted to obtain the Johnson–Cook constitutive model parameters of the alloy.Simulations of the machining process were carried out using the Deform-3D finite element software.The results showed that the rheological stress increased with the increase in strain rate and the decrease in temperature.The increase in the cutting speed and feed caused the cutting temperature to rise sharply,whereas the influence of the cutting amount on the cutting temperature was weak.Because of the presence of chip nodules,there was extremum in the cutting force vs cutting speed curves.The increase in the feed and cutting depth increased the cutting area Ac,so the cutting force also increased.The simulation results were verified by experiments.The simulation predictions were in good agreement with the test values,and the cutting force and temperature variations with the cutting parameters were the same.Thus,the correctness of the 7A09 aluminum alloy finite element model was verified. 展开更多
关键词 7A09 aluminum alloy double liquid quenching dynamic impact performance CUTTING finite element method(FEM)
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Influence of Underground Mining on Ground Surface and Railway Bridge Under Thick Alluvium 被引量:8
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作者 GE Xin-hui YU Guang-yun 《Journal of China University of Mining and Technology》 EI 2006年第1期97-100,共4页
Patterns of ground movement and pore water pressure variation are obtained through a case study using a finite element method. With the progress of excavation, ground subsidence, ground inclination and horizontal disp... Patterns of ground movement and pore water pressure variation are obtained through a case study using a finite element method. With the progress of excavation, ground subsidence, ground inclination and horizontal displacement accelerates. Along the striking direction, a subsidence basin is formed on the ground surface induced by underground mining. The maximum subsidence is around 5.41m. The ratio of ground subsidence to the thickness of the coal seam is 1.08. The maximum inclination is 11.5 mm/m. The maximum horizontal displacement is 2.15 mm/m. At the time the coal has been excavated, the maximum pore water pressure reaches 25 kPa. In order to improve protection of structures lo- cated over the area with underground mining, the variation of additional stresses of a railway bridge induced by ground surface deformation is analyzed. The main effect of underground mining on the railway bridge is the tensile stress and the maximum value reaches as high as 4.29 MPa, which is greater than the concrete tensile strength. 展开更多
关键词 thick alluvium ground surface movement disturbed soil finite element method.
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Analysis and numerical simulation of dynamic effect on rock under high pressure water jet 被引量:1
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作者 李晓红 司鹄 王丹丹 《Journal of Coal Science & Engineering(China)》 2008年第2期209-212,共4页
Based on continuum mechanics and rock dynamics,analyzed the micro-struc- ture damage of rock and the impulsive effect under high pressure water jet and developed the dynamic model.Further,on the assumption of that roc... Based on continuum mechanics and rock dynamics,analyzed the micro-struc- ture damage of rock and the impulsive effect under high pressure water jet and developed the dynamic model.Further,on the assumption of that rock was homogeneous and iso- tropic,a computational model was established based on nonlinear finite element and Arbi- trary Lagrangian-Eulerian(ALE) method.The dynamic effect impacted on rock under high pressure water jet was simulated by the dynamic contact method.The propagation of stress wave in rock was numerically simulated at different impacting velocity.The results show that the propagation velocity of stress wave is proportional to the impacting velocity of high pressure water jet.The faster the impacting velocity is,the quicker the comedown of stress wave. 展开更多
关键词 high pressure waterjet impulsive dynamics stress wave nonlinear finite element
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MINIMUM-PHASE FIR PRECODER DESIGN FOR MULTICASTING OVER MIMO FREQUENCY-SELECTIVE CHANNELS
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作者 Du Baisheng Xu Xiaodong Dai Xuchu 《Journal of Electronics(China)》 2013年第4期319-327,共9页
To maximize the throughput of frequency-selective multicast channel, the minimum-phase Finite Impulse Response (FIR) precoder design is investigated in this paper. This problem can be solved in two steps. Firstly, we ... To maximize the throughput of frequency-selective multicast channel, the minimum-phase Finite Impulse Response (FIR) precoder design is investigated in this paper. This problem can be solved in two steps. Firstly, we focus on designing a nonminimum-phase FIR precoder under the criterion of maximizing the throughput, and develop two efficient algorithms for the FIR precoder design from perspectives of frequency domain and time domain. In the second step, based on the theory of spectral factorization, the nonminimum-phase FIR precoder is transformed into the corresponding minimum-phase FIR precoder by a classic iterative algorithm without affecting the throughput. Numerical results indicate that the achievable rate of the proposed design has remarkable improvement over that of existing schemes, moreover, the group delay introduced by the FIR precoder is minimized. 展开更多
关键词 Finite hnpulse Response (FIR) precoder Physical layer multicasting Frequency-selectivechannel Minimum-phase filter
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Numerical simulation of deep-level rockburst in Fuxin coalfield
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作者 唐巨鹏 潘一山 李英杰 《Journal of Coal Science & Engineering(China)》 2005年第1期13-16,共4页
On the basis of ANSYS finite element model(FEM) software, the deep-level rockburst in Fuxin coalfield was simulated numerically. Based on Haizhou Mine and Wulong Mine as two typical deep-level rockburst examples in Fu... On the basis of ANSYS finite element model(FEM) software, the deep-level rockburst in Fuxin coalfield was simulated numerically. Based on Haizhou Mine and Wulong Mine as two typical deep-level rockburst examples in Fuxin coalfield, the rules and characteristics of the deep-level rockburst were analyzed. And the models were es- tablished. For Haizhou mine, the relationship between mining distance and rockburst was presented when 100, 300, 600 m were mined in 3313 working face. When 300 m were mined, the rockburst began to emerge. When 600 m were mined, the rockburst was the most possible to happen and the compression stress of the working face reached to the maximum value. The effect of tectonic stress on synclinal axis is also a key factor to rockburst occurrence. This was verified by the rockburst happened when 496 m were mined. For Wulong mine, based on the 311 working face as an example, the contours of Y stress in the roof and floor were obtained when the mining distance were 100, 200, 300 and 400 m. When 100 and 400 m were mined, the high stress con- centration regions occurred in the front of working face. This shows the rockburst is easy to happen. It is confirmed by the rockburst when 91m were mined in 311 working plane. The above indicates that the numerical simulation has instructive rule to study the deep-level rockburst in Fuxin coalfield. 展开更多
关键词 Fuxin coalfield ANSYS deep-level rockburst numerical simulation finite element model
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Study on Water-Soluble Organic Reducing Substances. I. Determination of Organic Reducing Substances by Differential Pulse Voltammetry
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作者 WUYOU-XIAN DINGCHANG-PU 《Pedosphere》 SCIE CAS CSCD 1991年第2期157-167,共11页
A new method was proposed for study of organic reducing substances in soils. According to the theoretical relationship between the voltammetric behaviors and reduction-oxidation reaction of reducing substances, the wo... A new method was proposed for study of organic reducing substances in soils. According to the theoretical relationship between the voltammetric behaviors and reduction-oxidation reaction of reducing substances, the working conditions of differential pulse voltammetry (d.p. v.) for determining the organic reducing substances produced during the processes of the anaerobic decomposition of plant materials were established with a glass carbon electrode as working electrode, 1 M Ag-AgCl electrode with large area as reference electrode, 0.2 M NH4AC as supporting electrolyte and pH buffer solution, pulse amplitude (AE) of 25 mV, scan rate at 2 mV·S-1and scan potential ranging from -0.5 to +1.2 voltage(vs. M Ag-AgCl). The peak current proportional to the concentration of reducing substances, and the characteristic peak potential of each organic reducing substance were regarded as the quantitative and qualitative base, respectively. These results obtained under the conditions mentioned above directly reflect both the reducing intensity and capacity of the organic reducing system in soils. 展开更多
关键词 differential pulse voltammetry organic reducing substances peak current peak potential
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3D Finite Element Analysis of a Man Hip Joint Femur under Impact Loads
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作者 YU Xue-zhong GUO Yi-mu +2 位作者 LI Jun ZHANG Yun-qiu HE Rong-xin 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第1期1-7,共7页
Objective: The biomechanical characters of the bone fracture of the man femoral hip joint under impact loads are explored. Methods :A biosystem model of the man femoral hip joint by using the GE ( General Electric... Objective: The biomechanical characters of the bone fracture of the man femoral hip joint under impact loads are explored. Methods :A biosystem model of the man femoral hip joint by using the GE ( General Electric) lightspeed multi-lay spiral CT is conducted. A 3D finite element model is established by employing the finite element software ANSYS. The FE analysis mainly concentrates on the effects of the impact directions arising from intense movements and the parenchyma on the femoral hip joint on the stress distributions of the proximal femur. Results:The parenchyma on the hip joint has relatively large relaxation effect on the impact loads. Conclusion:Effects of the angle δ of the impact load to the anterior direction and the angle γ of the impact load to the femur shaft on the bone fracture are given;δ has larger effect on the stress and strain distributions than the angle γ,which mainly represents the fracture of the upper femur including the femoral neck fracture when the posterolateral femur is impacted, consistent with the clinical resuits. 展开更多
关键词 Femoral hip joint Impact loading 3 D finite element analysis
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An Unstructured Finite Volume Method for Impact Dynamics of a Thin Plate 被引量:1
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作者 Weidong Chen Yanchun Yu 《Journal of Marine Science and Application》 2012年第4期478-485,共8页
The examination of an unstructured finite volume method for structural dynamics is assessed for simulations of systematic impact dynamics. A robust display dual-time stepping method is utilized to obtain time accurate... The examination of an unstructured finite volume method for structural dynamics is assessed for simulations of systematic impact dynamics. A robust display dual-time stepping method is utilized to obtain time accurate solutions. The study of impact dynamics is a complex problem that should consider strength models and state equations to describe the mechanical behavior of materials. The current method has several features, l) Discrete equations of unstructured finite volume method naturally follow the conservation law. 2) Display dual-time stepping method is suitable for the analysis of impact dynamic problems of time accurate solutions. 3) The method did not produce grid distortion when large deformation appeared. The method is validated by the problem of impact dynamics of an elastic plate with initial conditions and material properties. The results validate the finite element numerical data 展开更多
关键词 unstructured finite volume method structural impact dynamics large deformation strength models state equations
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New Interference Estimation for Power Control in Wireless Networks
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作者 Pyung-soo KIM Jeong-hun CHOI +2 位作者 Eung-hyuk LEE Doo-hee JUNG Eung-tae KIM 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期152-156,共5页
This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fl... This paper proposes new interference estimation for power control in broadband wireless data networks. The proposed approach gives the filtered interference power in real-time removing undesired effects such as the fluctuation of interference power and the measurement noise due to receiver noise. The well-known Finite Impulse Response (FIR) structure filter is adopted for both the interference and the noise covarianee estimation. The proposed mechanism provides both the filtered interference power and the filtered number of active co-channel interferers, which shows good inherent properties. And the filtered interference power is not affected by the constant number of active co-channel interferes. It is also shown that the filtered number of active co-channel interference is separated from the filtered interference power. From discussions about the choice of design parameters such as window length and eovariance ratio, they can make the estimation performance of the proposed FIR filtering based mechanism as good as possible. Via extensive computer simulations, the performance of the proposed mechanism is shown to be superior to the existing Kalman filtering based mechanism. 展开更多
关键词 power control interference estimation FIR filtering Kalman filtering
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Effects of parameters on rotational fine blanking of helical gears 被引量:3
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作者 杨珊 宋燕利 张梅 《Journal of Central South University》 SCIE EI CAS 2014年第1期50-57,共8页
The application of fine blanking to the manufacturing of helical gears directly from a strip has been restricted due to the traditional linear cutting stroke of the punch and die.In this work,rotational fine blanking ... The application of fine blanking to the manufacturing of helical gears directly from a strip has been restricted due to the traditional linear cutting stroke of the punch and die.In this work,rotational fine blanking which combined the linear and rotational motion of punch and counterpunch was applied for the forming of helical gears.A three-dimensional(3D) rigid-plastic finite element model was developed on the DEFORM-3D platform.By finite element simulation and analysis,the influences of key parameters on the punch load and cut surface were investigated.It is shown that: 1) with increasing the counterforce or helical angle,the punch load and the depth of die roll increase; 2) with increasing blank holder force,the punch load increases while the depth of die roll decreases; 3) V-ring indenter facilitates an improvement in the quality.The results of this research reveal the deformation mechanism of rotational fine blanking of helical gears,and provide valuable guidelines for further experimental studies. 展开更多
关键词 rotational fine blanking helical gear finite element simulation
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