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Optimization strategies for operational parameters of Rydberg atom-based amplitude modulation receiver
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作者 Yuhao Wu Dongping Xiao +1 位作者 Huaiqing Zhang Sheng Yan 《Chinese Physics B》 2025年第1期280-287,共8页
The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches... The Rydberg atom-based receiver, as a novel type of antenna, demonstrates broad application prospects in the field of microwave communications. However, since Rydberg atomic receivers are nonlinear systems, mismatches between the parameters of the received amplitude modulation(AM) signals and the system's linear workspace and demodulation operating points can cause severe distortion in the demodulated signals. To address this, the article proposes a method for determining the operational parameters based on the mean square error(MSE) and total harmonic distortion(THD) assessments and presents strategies for optimizing the system's operational parameters focusing on linear response characteristics(LRC) and linear dynamic range(LDR). Specifically, we employ a method that minimizes the MSE to define the system's linear workspace, thereby ensuring the system has a good LRC while maximizing the LDR. To ensure that the signal always operates within the linear workspace, an appropriate carrier amplitude is set as the demodulation operating point. By calculating the THD at different operating points, the LRC performance within different regions of the linear workspace is evaluated, and corresponding optimization strategies based on the range of signal strengths are proposed. Moreover, to more accurately restore the baseband signal, we establish a mapping relationship between the carrier Rabi frequency and the transmitted power of the probe light, and optimize the slope of the linear demodulation function to reduce the MSE to less than 0.8×10^(-4). Finally, based on these methods for determining the operational parameters, we explore the effects of different laser Rabi frequencies on the system performance, and provide optimization recommendations. This research provides robust support for the design of high-performance Rydberg atom-based AM receivers. 展开更多
关键词 Rydberg atom-based receiver amplitude modulation(AM) operating parameters optimization
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Pulsed gas–liquid discharge plasma catalytic degradation of bisphenol A over graphene/Cd S:process parameters optimization and O_(3)activation mechanism analysis
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作者 姜楠 李学川 +4 位作者 李举 李杰 廖兵 彭邦发 刘国 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第10期81-90,共10页
In the present work,pulsed gas–liquid hybrid discharge plasma coupled with graphene/Cd S catalyst was evaluated to eliminate bisphenol A(BPA)in wastewater.The optimization of a series of process parameters was perfor... In the present work,pulsed gas–liquid hybrid discharge plasma coupled with graphene/Cd S catalyst was evaluated to eliminate bisphenol A(BPA)in wastewater.The optimization of a series of process parameters was performed in terms of BPA degradation performance.The experimental results demonstrated that nearly 90%of BPA(20 mg l^(-1))in the synthetic wastewater(p H=7.5,σ=10μS m^(-1))was degraded by the plasma catalytic system over 0.2 g l^(-1)graphene/Cd S at 19k V with a 4 l min^(-1)air flow rate and 10 mm electrode gap within 60 min.The BPA removal rate increased with increasing the discharge voltage and decreasing the initial BPA concentration or solution conductivity.Nevertheless,either too high or too low an air flow rate,electrode gap,catalyst dosage or initial solution p H would lead to a decrease in BPA degradation.Moreover,optical emission spectroscopy was used to gain information on short-lived reactive species formed from the pulsed gas–liquid hybrid discharge plasma system.The results indicated the existence of several highly oxidative free radicals such as·O and·OH.Finally,the activation pathway of O_(3)on the catalyst surface was analyzed by density functional theory. 展开更多
关键词 pulsed discharge gas-liquid discharge wastewater treatment parameters optimization DFT calculation
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Parameters analysis and application of the differential excitation detection technology
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作者 于霞 张卫民 +2 位作者 陈国龙 邱忠超 曾卫琴 《Journal of Beijing Institute of Technology》 EI CAS 2015年第3期348-354,共7页
A differential excitation probe based on eddy current testing technology was designed. Sheet specimens of Q 235 steel with prefabricated micro-cracks of different widths and of aluminum with prefabricated micro-cracks... A differential excitation probe based on eddy current testing technology was designed. Sheet specimens of Q 235 steel with prefabricated micro-cracks of different widths and of aluminum with prefabricated micro-cracks of different depths were detected through the designed detection system. The characteristics of micro-cracks can be clearly showed after signals processing through the short-time Fourier transform( STFT). By changing the parameter and its value in detecting process,the factors including the excitation frequency and amplitude,the lift-off effect and the scanning direction were discussed,respectively. The results showed that the differential excitation probe was insensitive to dimension and surface state of the tested specimen,while it had a high degree of recognition for micro-crack detection. Therefore,when the differential excitation detection technology was used for inspecting micro-crack of turbine blade in aero-engine,and smoothed pseudo Wigner-Ville distribution was used for signal processing,micro-cracks of 0. 3 mm depth and 0. 1 mm width could be identified. The experimental results might be useful for further research on engineering test of turbine blades of aero-engine. 展开更多
关键词 differential excitation probe eddy current testing micro-crack defect influence parameters analysis
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Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation 被引量:2
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作者 Guo-Peng Yu Yong-Feng Cheng +1 位作者 Na Zhang Ping-Jian Ming 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期183-209,共27页
The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayto... The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully. 展开更多
关键词 Supercritical CO_(2)Brayton cycle Nuclear power generation thermo-economic analysis Multi-objective optimization Decision-making methods
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Hydrocarbon gas huff-n-puff optimization of multiple horizontal wells with complex fracture networks in the M unconventional reservoir
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作者 Hao-Chuan Zhang Yong Tang +5 位作者 You-Wei He Yong Qin Jian-Hong Luo Yu Sun Ning Wang De-Qiang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1018-1031,共14页
The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective meth... The oil production of the multi-fractured horizontal wells(MFHWs) declines quickly in unconventional oil reservoirs due to the fast depletion of natural energy. Gas injection has been acknowledged as an effective method to improve oil recovery factor from unconventional oil reservoirs. Hydrocarbon gas huff-n-puff becomes preferable when the CO_(2) source is limited. However, the impact of complex fracture networks and well interference on the EOR performance of multiple MFHWs is still unclear. The optimal gas huff-n-puff parameters are significant for enhancing oil recovery. This work aims to optimize the hydrocarbon gas injection and production parameters for multiple MFHWs with complex fracture networks in unconventional oil reservoirs. Firstly, the numerical model based on unstructured grids is developed to characterize the complex fracture networks and capture the dynamic fracture features.Secondly, the PVT phase behavior simulation was carried out to provide the fluid model for numerical simulation. Thirdly, the optimal parameters for hydrocarbon gas huff-n-puff were obtained. Finally, the dominant factors of hydrocarbon gas huff-n-puff under complex fracture networks are obtained by fuzzy mathematical method. Results reveal that the current pressure of hydrocarbon gas injection can achieve miscible displacement. The optimal injection and production parameters are obtained by single-factor analysis to analyze the effect of individual parameter. Gas injection time is the dominant factor of hydrocarbon gas huff-n-puff in unconventional oil reservoirs with complex fracture networks. This work can offer engineers guidance for hydrocarbon gas huff-n-puff of multiple MFHWs considering the complex fracture networks. 展开更多
关键词 Unconventional oil reservoir Complex fracture network Hydrocarbon gas huff-n-puff Parameter optimization Numerical simulation
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Optimization of Processing Parameters of Power Spinning for Bushing Based on Neural Network and Genetic Algorithms 被引量:3
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作者 Junsheng Zhao Yuantong Gu Zhigang Feng 《Journal of Beijing Institute of Technology》 EI CAS 2019年第3期606-616,共11页
A neural network model of key process parameters and forming quality is developed based on training samples which are obtained from the orthogonal experiment and the finite element numerical simulation. Optimization o... A neural network model of key process parameters and forming quality is developed based on training samples which are obtained from the orthogonal experiment and the finite element numerical simulation. Optimization of the process parameters is conducted using the genetic algorithm (GA). The experimental results have shown that a surface model of the neural network can describe the nonlinear implicit relationship between the parameters of the power spinning process:the wall margin and amount of expansion. It has been found that the process of determining spinning technological parameters can be accelerated using the optimization method developed based on the BP neural network and the genetic algorithm used for the process parameters of power spinning formation. It is undoubtedly beneficial towards engineering applications. 展开更多
关键词 power SPINNING process parameters optimization BP NEURAL network GENETIC algorithms (GA) response surface methodology (RSM)
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Optimization of CNC cutting parameters using design of experiment(DOE) and desirability function 被引量:3
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作者 Ender Hazir Emine Seda Erdinler Kücük Hüseyin Koc 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1423-1434,共12页
In this study,2~5 (five factors at two-level factorial design) design of experiment was applied to investigate a set of optimal machining parameters to achieve a minimum surface roughness value for Abies nordmannian... In this study,2~5 (five factors at two-level factorial design) design of experiment was applied to investigate a set of optimal machining parameters to achieve a minimum surface roughness value for Abies nordmanniana.Wood specimens were prepared using different values of spindle speed,feed rate,depth of cut,tool radius,and cutting directions.Average surface roughness (R_z) values were applied using a stylus.The objectives were to:(1)obtain the effective variables of wood surface roughness;(2) analyze which of these factors had an impact on variability in the CNC machining process;(3) evaluate the optimal cutting values within the range of different cutting levels of machining parameters.The results indicate that the design of experiment(DOE) based on the desirability function approach determined the optimal machining parameters successfully,leading to minimum R_a compared to the observed value.Minimum surface roughness values of tangential and radial cutting directions were 3.58 and 3.21 μm,respectively. 展开更多
关键词 Wood surface roughness optimization CNC Desirability function Pareto analysis
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Estimation of forest parameters based on TM imagery and statistical analysis 被引量:2
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作者 CHEN Wen-bo ZHAO Xiao-fan 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第3期241-244,共4页
One of the primary forestry research interests lies in estimating forest stand parameters by applying empirical or semi-empirical model to establish the relationship between the forest stand parameters and remote sens... One of the primary forestry research interests lies in estimating forest stand parameters by applying empirical or semi-empirical model to establish the relationship between the forest stand parameters and remote sensing data. Using remote sensing image and the inventory data from 2 compartments in northeast Florida, U.S.A., this paper explored the correlation between forest stand parameters and Landsat TM spectral digital number (DN) value. Results showed that less than 50% of the total variance could be explained by linear regression models with only either a single band or such vegetation indices as vegetation index (VI) or normalized difference vegetation index (NDVI) as predicators. In consequence, multi-linear regression models which synthesized more predicators were introduced to estimate forest parameters. Regression results were tested in terms of the other group of data, and verification showed a better capability of explaining over 75% variance except for forest density. The weakness and further improvement of prediction models were also discussed in the article. This paper is expected to provide a better understanding of the relationship between TM spectral and forest characteristics 展开更多
关键词 TM image DN value Estimation of forest parameters Correlation and regression analysis
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Data network traffic analysis and optimization strategy of real-time power grid dynamic monitoring system for wide-frequency measurements 被引量:4
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作者 Jinsong Li Hao Liu +2 位作者 Wenzhuo Li Tianshu Bi Mingyang Zhao 《Global Energy Interconnection》 EI CAS CSCD 2022年第2期131-142,共12页
The application and development of a wide-area measurement system(WAMS)has enabled many applications and led to several requirements based on dynamic measurement data.Such data are transmitted as big data information ... The application and development of a wide-area measurement system(WAMS)has enabled many applications and led to several requirements based on dynamic measurement data.Such data are transmitted as big data information flow.To ensure effective transmission of wide-frequency electrical information by the communication protocol of a WAMS,this study performs real-time traffic monitoring and analysis of the data network of a power information system,and establishes corresponding network optimization strategies to solve existing transmission problems.This study utilizes the traffic analysis results obtained using the current real-time dynamic monitoring system to design an optimization strategy,covering the optimization in three progressive levels:the underlying communication protocol,source data,and transmission process.Optimization of the system structure and scheduling optimization of data information are validated to be feasible and practical via tests. 展开更多
关键词 Power system Data network Wide-frequency information Real-time system Traffic analysis optimization strategy
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Transient analysis and optimization of passive residual heat removal heat exchanger in advanced nuclear power plant 被引量:3
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作者 Yan-Bin Liu Xiang-Yu Meng +3 位作者 Xue-Sheng Wang Qi-Ming Men Yu-Yang Yuan Jia-Ming Cao 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第8期147-162,共16页
The transient performance and optimization of a passive residual heat removal heat exchanger(PRHR HX)were investigated.First,a calculation method was developed for predicting the heat transfer of the PRHR HX.The calcu... The transient performance and optimization of a passive residual heat removal heat exchanger(PRHR HX)were investigated.First,a calculation method was developed for predicting the heat transfer of the PRHR HX.The calculation results were validated through comparisons with ROSA experimental data.The heat-transfer performance of the AP1000 PRHR HX in the initial period was predicted,and it satisfied the design requirements.Second,the distributions of the heat flux,tube-inside/outside heattransfer coefficients,and heat load for the AP1000 PRHR HX over 2000 s were examined.Third,an optimization study was conducted by adjusting the horizontal length and tube diameter.Their effects on the four main heat-transfer parameters and the heat-transfer area were analyzed.Furthermore,the influence of the initial in-containment refueling water storage tank(IRWST)temperature was investigated using an established simulation procedure.The results indicated that it significantly affected the trends of the IRWST temperature and reactor outlet temperature.Finally,the minimum required flow rates over time to maintain the reactor outlet temperature at the safety line were determined for different start-up times.The trends of the minimum required flow rate and the peak flow rate were analyzed. 展开更多
关键词 Heat transfer PRHR HX Transient analysis optimization investigation
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Mechanical Analysis and Optimization of ITER Upper ELM Coil & Feeder 被引量:1
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作者 张善文 宋云涛 +8 位作者 王忠伟 卢速 戢翔 杜双松 刘旭峰 冯昌乐 杨洪 王松可 罗志仁 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第8期794-799,共6页
International thermonuclear experimental reactor (ITER) edge localized mode (ELM) coils are used to mitigate or suppress ELMs. The location of the coils in the vacuum vessel and behind the blankets exposes them to... International thermonuclear experimental reactor (ITER) edge localized mode (ELM) coils are used to mitigate or suppress ELMs. The location of the coils in the vacuum vessel and behind the blankets exposes them to high radiation levels and high temperatures. The feeders provide the power and cooling water for ELM coils. They are located in the chinmey ports and experience lower radiation and temperature levels. These coils and feeders work in a high magnetic field environment and are subjected to alternating electromagnetic force due to the interaction between high magnetic field and alternating current (AC) current in the coils. They are also subjected to thermal stresses due to thermal expansion. Using the ITER upper ELM coil and feeder as an example, mechanical analyses are performed to verify and optimize the updated design to enhance their structural performance. The results show that the conductor, jacket and bracket can meet the static, fatigue and crack threshold criteria. The optimization indicates that adding chamfers to the bracket can reduce the high stress of the bracket, and removing two rails can reduce the peak reaction force on the two rails arising from thermal expansion. 展开更多
关键词 ELM coil FEEDER mechanical analysis optimization
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Calibration and uniqueness analysis of microparameters for DEM cohesive granular material 被引量:4
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作者 Songtao Ji Jurij Karlovšek 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第1期121-136,共16页
The differential evolution(DE)algorithm was deployed to calibrate microparameters of the DEM cohesive granular material.4 macroparameters,namely,uniaxial compressive strength,direct tensile strength,Young’s modulus a... The differential evolution(DE)algorithm was deployed to calibrate microparameters of the DEM cohesive granular material.4 macroparameters,namely,uniaxial compressive strength,direct tensile strength,Young’s modulus and Poisson’s ratio,can be calibrated to high accuracy.The best calibration accuracy could reach the sum of relative errors RE_(sum)<0.1%.Most calibrations can be achieved with RE_(sum)<5%within hours or RE_(sum)<1%within 2 days.Based on the calibrated results,microparameters uniqueness analysis was carried out to reveal the correlation between microparameters and the macroscopic mechanical behaviour of material:(1)microparameters effective modulus,tensile strength and normal-to-shear stiffness ratio control the elastic behaviour and stable crack growth,(2)microparameters cohesion and friction angles present a negative linear correlation that controls the axial strain and lateral strain prior to the peak stress,and(3)microparameters friction coefficient controls shear crack friction and slip mainly refers to the unstable crack behaviour.Consideration of more macroparameters to regulate the material mechanical behaviour that is dominated by shear crack and slip motion is highlighted for future study.The DE calibration method is expected to serve as an alternative method to calibrate the DEM cohesive granular material to its peak strength. 展开更多
关键词 Discrete element method(DEM) Particle flow code(PFC) Differential evolution(DE) Parameter calibration Uniqueness analysis Post-peak behaviour
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Application of the Tikhonov regularization method to wind retrieval from scatterometer data I.Sensitivity analysis and simulation experiments 被引量:1
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作者 钟剑 黄思训 +1 位作者 杜华栋 张亮 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期274-283,共10页
Scatterometer is an instrument which provides all-day and large-scale wind field information, and its application especially to wind retrieval always attracts meteorologists. Certain reasons cause large direction erro... Scatterometer is an instrument which provides all-day and large-scale wind field information, and its application especially to wind retrieval always attracts meteorologists. Certain reasons cause large direction error, so it is important to find where the error mainly comes. Does it mainly result from the background field, the normalized radar cross-section (NRCS) or the method of wind retrieval? It is valuable to research. First, depending on SDP2.0, the simulated 'true' NRCS is calculated from the simulated 'true' wind through the geophysical mode] function NSCAT2. The simulated background field is configured by adding a noise to the simulated 'true' wind with the non-divergence constraint. Also, the simulated 'measured' NRCS is formed by adding a noise to the simulated 'true' NRCS. Then, the sensitivity experiments are taken, and the new method of regularization is used to improve the ambiguity removal with simulation experiments. The results show that the accuracy of wind retrieval is more sensitive to the noise in the background than in the measured NRCS; compared with the two-dimensional variational (2DVAR) ambiguity removal method, the accuracy of wind retrieval can be improved with the new method of Tikhonov regularization through choosing an appropriate regularization parameter, especially for the case of large error in the background. The work will provide important information and a new method for the wind retrieval with real data. 展开更多
关键词 SCATTEROMETER variational optimization analysis wind retrieval regularization method
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Breakage and separation mechanism of ZGM coal mill based on parameters optimization model 被引量:5
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作者 Wei Hua He Yaqun +3 位作者 Shi Fengnian Zhou Nianxing Wang Shuai Ge Linhan 《International Journal of Mining Science and Technology》 SCIE EI 2014年第2期285-289,共5页
Sampling ports were firstly drilled on a ZGM95 coal mill in the power plant in China, and the coal samples from various points in the pulverizer were collected under the different operation conditions. The prop- erty ... Sampling ports were firstly drilled on a ZGM95 coal mill in the power plant in China, and the coal samples from various points in the pulverizer were collected under the different operation conditions. The prop- erty of the sampling material from the mill was analyzed, applying the float-sink test, size distribution analysis, proximate analysis and so on. It was indicated that the +250 I^m fraction in the pulverized fuel accounted for only 0.02%, while it was 83.2% in the new feed. The circulating ratio and coal flow in the separator and the cone zone were calculated using the mass balance of the circulating load. So, the cir- culating ratio in the separator of the pulverizer was between 8 and 13, and the circulating ratio, the feed flow of separator and cone zone all raised with the increase of the air volume. Furthermore, the parameters of the separation functions were obtained based on the fitting method. It was shown that the mean value of the shape factor B was 0.7617, and the parameter D which is the particle size at 50% cumulative yield in the separator almost kept unchanged. 展开更多
关键词 ZGM mill Coal grinding parameters optimization Mass balance
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Numerical analysis on the effect of process parameters on deposition geometry in wire arc additive manufacturing 被引量:1
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作者 Shilong FAN Fei YANG +3 位作者 Xiaonan ZHU Zhaowei DIAO Lin CHEN Mingzhe RONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第4期1-12,共12页
Here we develop a two-dimensional numerical model of wire and arc additive manufacturing(WAAM)to determine the relationship between process parameters and deposition geometry,and to reveal the influence mechanism of p... Here we develop a two-dimensional numerical model of wire and arc additive manufacturing(WAAM)to determine the relationship between process parameters and deposition geometry,and to reveal the influence mechanism of process parameters on deposition geometry.From the predictive results,a higher wire feed rate matched with a higher current could generate a larger and hotter droplet,and thus transfer more thermal and kinetic energy into melt pool,which results in a wider and lower deposited layer with deeper penetration.Moreover,a higher preheat temperature could enlarge melt pool volume and thus enhance heat and mass convection along both axial and radial directions,which gives rise to a wider and higher deposited layer with deeper penetration.These findings offer theoretical guidelines for the acquirement of acceptable deposition shape and optimal deposition quality through adjusting process parameters in fabricating WAAM components. 展开更多
关键词 additive manufacturing arc plasma process parameter deposition geometry numerical analysis
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Inverse displacement analysis of the general six degree-of-freedom serial robot based on optimization method 被引量:1
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作者 赵永杰 《Journal of Chongqing University》 CAS 2011年第2期60-67,共8页
The paper presents a new solution of inverse displacement analysis of the general six degree-of-freedom serial robot.The inverse displacement analysis of the general serial robot is transformed into a minimization pro... The paper presents a new solution of inverse displacement analysis of the general six degree-of-freedom serial robot.The inverse displacement analysis of the general serial robot is transformed into a minimization problem and then the optimization method is adopted to solve the nonlinear least squares problem with the analytic form of new Jacobian matrix.In this way,joint variables of the general serial robot can be searched out quickly under the desired precision when positions of the three non-collinear end effector points are given.Compared with the general Newton iterative method,the proposed algorithm can search out the solution when the robot is at the singular configuration and the initial configuration used in the optimization method may also be the singular configuration.So the convergence domain is bigger than that of the general Newton iterative method.Another advantage of the proposed algorithm is that positions of the three non-collinear end effector points are usually much easier to be measured than the orientation of the end effector.The inverse displacement analysis of the general 6R(six-revolute-joint) serial robot is illustrated as an example and the simulation results verify the efficiency of the proposed algorithm.Because the three non-collinear points can be selected at random,the method can be applied to any other types of serial robots. 展开更多
关键词 inverse displacement analysis general serial robot optimization method
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Rationale of Timed-Release Analysis and the Improvement of Flotation Experiment
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作者 刘炯天 周振英 +2 位作者 李备备 沈正义 王进才 《International Journal of Mining Science and Technology》 SCIE EI 1998年第2期113-117,共5页
The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward... The fundamental aspects of The Timed-Release Analysis (TRA) and some problems are analysed. Having studied the attribute of optimum flotation test results and the way of optimum test conditions, the auther put forward a proposal to improve this test method by adding a new test step of scavenging flotation and using optimum test conditions varied with different fine coals instead of the given ones settled by the TRA norm. Comparison between test results of the two methods of TRA shows that the improved method is very good. 展开更多
关键词 laboratory COAL FLOTATION TEST Method timed-release analysis optimization of TEST conditions optimum results of COAL FLOTATION
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Finite Element Analysis for the Structure Optimization Design of the CPUE Load-Bearing Wheel of Tracked Vehicle
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作者 于立彪 郑慕侨 张英 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期162-165,共4页
A new kind of material cast polyurethane elastomers (CPUE) is introduced to take the place of rubber on load bearing wheel for the first time. Based on load bearing wheel dimensions, material properties and operatin... A new kind of material cast polyurethane elastomers (CPUE) is introduced to take the place of rubber on load bearing wheel for the first time. Based on load bearing wheel dimensions, material properties and operating conditions, the structure of wheel flange is optimized by zero order finite element method. A detailed three dimensional finite element model of flange of load bearing wheel is developed and utilized to optimize structure of wheel flange. Its service life, which is affected by flange structure parameter, is analyzed by comparing the optimization results with those of prototype of wheel. The results of optimization are presented and the stress field of load bearing wheel in optimal dimension obtained by using finite element analysis method is demonstrated. The finite element analysis and optimization results show that the CPUE load bearing wheel is feasible and suitable for the tracked vehicle and has a guiding value in practice of the weighting design of the whole tracked vehicle. 展开更多
关键词 zero order finite element analysis structure optimization cast polyurethane elastomers(CPUE) load bearing wheel durability
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Design optimization on the front wheel orientation parameters of a vehicle
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作者 褚志刚 《Journal of Chongqing University》 CAS 2003年第2期12-15,共4页
A uniform optimization object function for front wheel orientation parameters of a vehicle is reported, which includes the tolerances of practical values and set values of front wheel orientation parameters under full... A uniform optimization object function for front wheel orientation parameters of a vehicle is reported, which includes the tolerances of practical values and set values of front wheel orientation parameters under full load, and the changing value of each parameter with front wheel fluctuation to build a front suspension model for optimization analysis based on the multi-body dynamic (MD) theory. The original suspension is optimized with this model, and the variation law of each parameter with front wheel fluctuation is obtained. The results of a case study demonstrate that the front wheel orientation parameters of the optimized vehicle are reasonable under typical conditions and the variation of each parameter is in an ideal range with the wheel fluctuating within 40 mm. In addition, the driving performance is improved greatly in the road test and practical use. 展开更多
关键词 SUSPENSION optimization multi-body dynamics front wheel orientation parameter
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Particle swarm optimization and its application to the design of a compact tunable guided-mode resonant filter
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作者 Dan-Yan Wang Qing-Kang Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期451-455,共5页
A compact tunable guided-mode resonant filter (GMRF) in the telecommunication region near the 1550 nm wave-length is proposed in this paper. Particle swarm optimization (PSO) is used to design the GMRF. The tunabi... A compact tunable guided-mode resonant filter (GMRF) in the telecommunication region near the 1550 nm wave-length is proposed in this paper. Particle swarm optimization (PSO) is used to design the GMRF. The tunability of the GMRF is achieved by an MEMS-based physical movement (in the horizontal or vertical direction) combined with an incident angle in a certain range. The results show that the resonant wavelength tuning of 110 nm (140mm) is obtained by horizontal movement of 168 nm (vertical movement of 435 nm) combined with an about 11° variation of incident angle. 展开更多
关键词 guided-mode resonant filter (GMRF) particle swarm optimization (PSO) tunable filter rigorous coupled wave analysis (RCWA)
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