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Amodified variable rate particle filter for maneuvering target tracking

Yun-fei GUO,Kong-shuai FAN,Dong-liang PENG,Ji-an LUO,Han SHENTU

《信息与电子工程前沿(英文)》 2015年 第16卷 第11期   页码 985-994 doi: 10.1631/FITEE.1500149

摘要: To address the problem of maneuvering target tracking, where the target trajectory has prolonged smooth regions and abrupt maneuvering regions, a modified variable rate particle filter (MVRPF) is proposed. First, a Cartesian-coordinate based variable rate model is presented. Compared with conventional variable rate models, the proposed model does not need any prior knowledge of target mass or external forces. Consequently, it is more convenient in practical tracking applications. Second, a maneuvering detection strategy is adopted to adaptively adjust the parameters in MVRPF, which helps allocate more state points at high maneuver regions and fewer at smooth regions. Third, in the presence of small measurement errors, the unscented particle filter, which is embedded in MVRPF, can move more particles into regions of high likelihood and hence can improve the tracking performance. Simulation results illustrate the effectiveness of the proposed method.

关键词: Maneuvering target tracking     Prolonged smooth regions     Variable rate model     Maneuver detection    

Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

《工程管理前沿(英文)》 2014年 第1卷 第2期   页码 160-175 doi: 10.15302/J-FEM-2014024

摘要: This paper proposes an economic growth model based on the Six Basic Factors of Production and Xu Growth Rate Equation for the first time, which fills-in the deficits of the New Classical Economic Growth Model based on the Solow Model. The empirical analysis indicates that over the past three decades, the consumption of six basic factors of production had complicated relations with economic growth. In some years, the consumption rate of the basic factors of production was meager, but the economy witnessed relatively rocketing growth rate; in some years, the factors of production consumption rate was very high, but the economy growth rate slowed down. In general, economy grows at the expenses of huge consumption of four factors. There is an obvious characteristic of huge input and low efficiency. The average contribution rate of technological advance peaks in the middle, while it drops down at two ends. Noticeably, since 2004, the technology contribution rate generally shows a downward trend, reasons of which should be explored systematically in aspects like economic policy and industry structure with a view to boost further transformation of the macro-economy scientific growth model.

关键词: six basic factors of production     economic growth model     Xu Growth Rate Equation    

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

《环境科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 313-319 doi: 10.1007/s11783-009-0025-4

摘要: This investigation was carried out to establish a new domestic landfill gas (LFG) generation rate model that takes into account the impact of leachate recirculation. The first-order kinetics and two-stage reaction (FKTSR) model of the LFG generation rate includes mechanisms of the nutrient balance for biochemical reaction in two main stages. In this study, the FKTSR model was modified by the introduction of the outflow function and the organic acid conversion coefficient in order to represent the in-situ condition of nutrient loss through leachate. Laboratory experiments were carried out to simulate the impact of leachate recirculation and verify the modified FKTSR model. The model calibration was then calculated by using the experimental data. The results suggested that the new model was in line with the experimental data. The main parameters of the modified FKTSR model, including the LFG production potential (), the reaction rate constant in the first stage (), and the reaction rate constant in the second stage () of 64.746 L, 0.202 d, and 0.338 d, respectively, were comparable to the old ones of 42.069 L, 0.231 d, and 0.231 d. The new model is better able to explain the mechanisms involved in LFG generation.

关键词: landfill gas (LFG)     generation rate model     first-order kinetics     two-stage reaction     outflow function    

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1411-9

摘要:

• Actual SAORs was determined using MLVSS and temperature.

关键词: Specific ammonia oxidation rate     Sequencing batch reactor     Biomass     Temperature coefficient     Model simulation    

A rate-dependent Prandtl-Ishlinskii model for piezoelectric actuators using the dynamic envelope function

Meiju YANG,Chunxia LI,Guoying GU,Limin ZHU

《机械工程前沿(英文)》 2015年 第10卷 第1期   页码 37-42 doi: 10.1007/s11465-015-0326-1

摘要:

In this paper, a novel rate-dependent Prandtl-Ishlinskii (P-I) model is proposed to characterize the rate-dependent hysteresis nonlinearity of piezoelectric actuators. The new model is based on a modified rate-dependent play operator, in which a dynamic envelope function is introduced to replace the input function of the classical play operator. Moreover, a dynamic density function is utilized in the proposed P-I model. The parameters of the proposed model are identified by a modified particle swarm optimization algorithm. Finally, experiments are conducted on a piezo-actuated nanopositioning stage to validate the proposed P-I model under the sinusoidal inputs. The experimental results show that the developed rate-dependent P-I model precisely characterize the rate-dependent hysteresis loops up to 1000 Hz.

关键词: piezoelectric actuators     hysteresis     Prandtl-Ishlinskii     rate-dependent    

Performance design of a cryogenic air separation unit for variable working conditions using the lumpedparameter model

Jinghua XU, Tiantian WANG, Qianyong CHEN, Shuyou ZHANG, Jianrong TAN

《机械工程前沿(英文)》 2020年 第15卷 第1期   页码 24-42 doi: 10.1007/s11465-019-0558-6

摘要: Large-scale cryogenic air separation units (ASUs), which are widely used in global petrochemical and semiconductor industries, are being developed with high operating elasticity under variable working conditions. Different from discrete processes in traditional machinery manufacturing, the ASU process is continuous and involves the compression, adsorption, cooling, condensation, liquefaction, evaporation, and distillation of multiple streams. This feature indicates that thousands of technical parameters in adsorption, heat transfer, and distillation processes are correlated and merged into a large-scale complex system. A lumped parameter model (LPM) of ASU is proposed by lumping the main factors together and simplifying the secondary ones to achieve accurate and fast performance design. On the basis of material and energy conservation laws, the piecewise-lumped parameters are extracted under variable working conditions by using LPM. Takagi–Sugeno (T–S) fuzzy interval detection is recursively utilized to determine whether the critical point is detected or not by using different thresholds. Compared with the traditional method, LPM is particularly suitable for “rough first then precise” modeling by expanding the feasible domain using fuzzy intervals. With LPM, the performance of the air compressor, molecular sieve adsorber, turbo expander, main plate-fin heat exchangers, and packing column of a 100000 Nm O /h large-scale ASU is enhanced to adapt to variable working conditions. The designed value of net power consumption per unit of oxygen production (kW/(Nm O )) is reduced by 6.45%.

关键词: performance design     air separation unit (ASU)     lumped parameter model (LPM)     variable working conditions     T–S fuzzy interval detection    

Power maximization of variable-speed variable-pitch wind turbines using passive adaptive neural fault

Hamed HABIBI, Hamed RAHIMI NOHOOJI, Ian HOWARD

《机械工程前沿(英文)》 2017年 第12卷 第3期   页码 377-388 doi: 10.1007/s11465-017-0431-4

摘要:

Power maximization has always been a practical consideration in wind turbines. The question of how to address optimal power capture, especially when the system dynamics are nonlinear and the actuators are subject to unknown faults, is significant. This paper studies the control methodology for variable-speed variable-pitch wind turbines including the effects of uncertain nonlinear dynamics, system fault uncertainties, and unknown external disturbances. The nonlinear model of the wind turbine is presented, and the problem of maximizing extracted energy is formulated by designing the optimal desired states. With the known system, a model-based nonlinear controller is designed; then, to handle uncertainties, the unknown nonlinearities of the wind turbine are estimated by utilizing radial basis function neural networks. The adaptive neural fault tolerant control is designed passively to be robust on model uncertainties, disturbances including wind speed and model noises, and completely unknown actuator faults including generator torque and pitch actuator torque. The Lyapunov direct method is employed to prove that the closed-loop system is uniformly bounded. Simulation studies are performed to verify the effectiveness of the proposed method.

关键词: wind turbine nonlinear model     maximum power tracking     passive fault tolerant control     adaptive neural control    

Improved rate-based modeling of carbon dioxide absorption with aqueous monoethanolamine solution

Stefania MOIOLI, Laura A. PELLEGRINI, Simone GAMBA, Ben LI

《化学科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 123-131 doi: 10.1007/s11705-014-1415-0

摘要: This paper focuses on modeling and simulation of a post-combustion carbon dioxide capture in a coal-fired power plant by chemical absorption using monoethanolamine. The aim is to obtain a reliable tool for process simulation: a customized rate-based model has been developed and implemented in the ASPEN Plus software, along with regressed parameters for the Electrolyte-NRTL model worked out in a previous research. The model is validated by comparison with experimental data of a pilot plant and can provide simulation results very close to experimental data.

关键词: Absorption     carbon dioxide capture     rate-based model     monoethanolamine scrubbing    

classification using Chinese advanced high-resolution satellite imagery and an object-oriented multi-variablemodel

Li-gang MA,Jin-song DENG,Huai YANG,Yang HONG,Ke WANG

《信息与电子工程前沿(英文)》 2015年 第16卷 第3期   页码 238-248 doi: 10.1631/FITEE.1400083

摘要: The Chinese ZY-1 02C satellite is one of the most advanced high-resolution earth observation systems designed for terrestrial resource monitoring. Its capability for comprehensive landscape classification, especially in urban areas, has been under constant study. In view of the limited spectral resolution of the ZY-1 02C satellite (three bands), and the complexity and heterogeneity across urban environments, we attempt to test its performance of urban landscape classification by combining a multivariable model with an object-oriented approach. The multiple variables including spectral reflection, texture, spatial autocorrelation, impervious surface fraction, vegetation, and geometry indexes were first calculated and selected using forward stepwise linear discriminant analysis and applied in the following object-oriented classification process. Comprehensive accuracy assessment which adopts traditional error matrices with stratified random samples and polygon area consistency (PAC) indexes was then conducted to examine the real area agreement between a classified polygon and its references. Results indicated an overall classification accuracy of 92.63% and a kappa statistic of 0.9124. Furthermore, the proposed PAC index showed that more than 82% of all polygons were correctly classified. Misclassification occurred mostly between residential area and barren/farmland. The presented method and the Chinese ZY-1 02C satellite imagery are robust and effective for urban landscape classification.

关键词: ZY-1 02C satellite     Classification     Urban     Multi-variable model    

Simulation of cohesive crack growth by a variable-node XFEM

Weihua FANG, Jiangfei WU, Tiantang YU, Thanh-Tung NGUYEN, Tinh Quoc BUI

《结构与土木工程前沿(英文)》 2020年 第14卷 第1期   页码 215-228 doi: 10.1007/s11709-019-0595-6

摘要: A new computational approach that combines the extended finite element method associated with variable-node elements and cohesive zone model is developed. By using a new enriched technique based on sign function, the proposed model using 4-node quadrilateral elements can eliminate the blending element problem. It also allows modeling the equal stresses at both sides of the crack in the crack-tip as assumed in the cohesive model, and is able to simulate the arbitrary crack-tip location. The multiscale mesh technique associated with variable-node elements and the arc-length method further improve the efficiency of the developed approach. The performance and accuracy of the present approach are illustrated through numerical experiments considering both mode-I and mixed-mode fracture in concrete.

关键词: extended finite element method     cohesive zone model     sign function     crack propagation    

Modification of the activated sludge model for chemical dosage

Shuai MA,Siyu ZENG,Xin DONG,Jining CHEN,Gustaf OLSSON

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 694-701 doi: 10.1007/s11783-014-0732-3

摘要: Full-scale experiments have been carried out to adapt the activated sludge model ASM2d to include the influence of metal dosage (Fe and Al ) for phosphorus removal. Phosphorus removal rates, nitrification rates, as well as pH and sludge settling performance, were evaluated as functions of the metal dosages. Furthermore, models relating certain parameters to the dosage of chemicals have been derived. Corresponding parameters in the ASM2d and the secondary settler models, included in the Benchmark Simulation Model No 1 (BSM1), have been modified to take the metal influence into consideration. Based on the effluent limits and penalty policy of China, an equivalent evaluation method was derived for the total cost assessment. A large number of 300-day steady-state and 14-day open-loop dynamic simulations were performed to demonstrate the difference in behavior between the original and the modified BSM1. The results show that 1) both in low and high mole concentrations, Fe addition results in a higher phosphorus removal rate than Al ; 2) the sludge settling velocity will increase due to the metal addition; 3) the respiration rate of the activated sludge is decreased more by the dosage of Al than Fe ; 4) the inhibition of Al on the nitrification rate is stronger than that of Fe ; 5) the total operating cost will reach the minimum point for smaller dosages of Fe , but always increase with Al addition.

关键词: chemical precipitation     benchmark simulation model     phosphorus removal     respiratory rate     sludge settling     activated sludge model    

Evaluation of measurement uncertainty of the high-speed variable-slit system based on the Monte Carlo

Yin ZHANG, Jianwei WU, Kunpeng XING, Zhongpu WEN, Jiubin TAN

《机械工程前沿(英文)》 2020年 第15卷 第4期   页码 517-537 doi: 10.1007/s11465-020-0589-z

摘要: This paper presents a dynamic and static error transfer model and uncertainty evaluation method for a high-speed variable-slit system based on a two-dimensional orthogonal double-layer air-floating guide rail structure. The motion accuracy of the scanning blade is affected by both the moving component it is attached to and the moving component of the following blade during high-speed motion. First, an error transfer model of the high-speed variable-slit system is established, and the influence coefficients are calculated for each source of error associated with the accuracy of the blade motion. Then, the maximum range of each error source is determined by simulation and experiment. Finally, the uncertainty of the blade displacement measurement is evaluated using the Monte Carlo method. The proposed model can evaluate the performance of the complex mechanical system and be used to guide the design.

关键词: air-floating guide rail     error transfer model     driving and following structure     dynamic error     uncertainty evaluation     Monte Carlo method    

Mechanical design, modeling, and identification for a novel antagonistic variable stiffness dexterous

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0691-5

摘要: This study traces the development of dexterous hand research and proposes a novel antagonistic variable stiffness dexterous finger mechanism to improve the safety of dexterous hand in unpredictable environments, such as unstructured or man-made operational errors through comprehensive consideration of cost, accuracy, manufacturing, and application. Based on the concept of mechanical passive compliance, which is widely implemented in robots for interactions, a finger is dedicated to improving mechanical robustness. The finger mechanism not only achieves passive compliance against physical impacts, but also implements the variable stiffness actuator principle in a compact finger without adding supererogatory actuators. It achieves finger stiffness adjustability according to the biologically inspired stiffness variation principle of discarding some mobilities to adjust stiffness. The mechanical design of the finger and its stiffness adjusting methods are elaborated. The stiffness characteristics of the finger joint and the actuation unit are analyzed. Experimental results of the finger joint stiffness identification and finger impact tests under different finger stiffness presets are provided to verify the validity of the model. Fingers have been experimentally proven to be robust against physical impacts. Moreover, the experimental part verifies that fingers have good power, grasping, and manipulation performance.

关键词: multifingered hand     mechanism design     robot safety     variable stiffness actuator    

一种基于高斯过程与粒子群算法的CNN超参数自动搜索混合模型优化算法 Research Article

闫涵,仲崇权,吴玉虎,张立勇,卢伟

《信息与电子工程前沿(英文)》 2023年 第24卷 第11期   页码 1557-1573 doi: 10.1631/FITEE.2200515

摘要: 卷积神经网络(CNN)在许多实际应用领域中有着快速发展。然而,CNN性能很大程度上取决于其超参数,而为CNN配置合适的超参数通常面临着以下3个挑战:(1)不同类型CNN超参数的混合变量编码问题;(2)评估候选模型的昂贵计算成本问题;(3)确保搜索过程中收敛速率和模型性能问题。针对上述问题,提出一种基于高斯过程(GP)和粒子群优化算法(PSO)的混合模型优化算法(GPPSO),用于自动搜索最优的CNN超参数配置。首先,设计一种新的编码方法高效编码CNN中不同类型的超参数。其次,提出一种混合代理辅助(HSA)模型降低评估候选模型的高计算成本。最后,设计一种新的激活函数改善模型性能并确保收敛速率。在图像分类基准数据集上进行了大量实验,验证GPPSO优于最先进的方法。以金属断口诊断为例,验证GPPSO算法在实际应用中的有效性。实验结果表明,GPPSO仅需0.04和1.70 GPU天即可在CIFAR-10和CIFAR-100数据集上实现95.26%和76.36%识别准确率。

关键词: 卷积神经网络;高斯过程;混合模型;超参数优化;混合变量;粒子群优化    

Variable stiffness and damping magnetorheological isolator

Yang ZHOU, Xingyu WANG, Xianzhou ZHANG, Weihua LI

《机械工程前沿(英文)》 2009年 第4卷 第3期   页码 310-315 doi: 10.1007/s11465-009-0039-4

摘要: This paper presents the development and characterization of a magnetorheological (MR) fluid-based variable stiffness and damping isolator. The prototype of the MR fluid isolator is fabricated, and its dynamic behavior is measured under various applied magnetic fields. The parameters of the model under various magnetic fields are identified, and the dynamic performance of the isolator is evaluated in simulation. Experimental results indicate that both the stiffness and damping capability of the developed MR isolator can be controlled by an external magnetic field.

关键词: magnetorheological (MR) fluid     stiffness     damping     mathematical model     dynamic performance     parameter identification    

标题 作者 时间 类型 操作

Amodified variable rate particle filter for maneuvering target tracking

Yun-fei GUO,Kong-shuai FAN,Dong-liang PENG,Ji-an LUO,Han SHENTU

期刊论文

Economic Growth Model Based on Six Basic Factors of Production—Xu Growth Rate Equation

Shou-bo Xu,Zong-yuan Huang

期刊论文

Modified landfill gas generation rate model of first-order kinetics and two-stage reaction

Jiajun CHEN , Hao WANG , Na ZHANG ,

期刊论文

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

期刊论文

A rate-dependent Prandtl-Ishlinskii model for piezoelectric actuators using the dynamic envelope function

Meiju YANG,Chunxia LI,Guoying GU,Limin ZHU

期刊论文

Performance design of a cryogenic air separation unit for variable working conditions using the lumpedparameter model

Jinghua XU, Tiantian WANG, Qianyong CHEN, Shuyou ZHANG, Jianrong TAN

期刊论文

Power maximization of variable-speed variable-pitch wind turbines using passive adaptive neural fault

Hamed HABIBI, Hamed RAHIMI NOHOOJI, Ian HOWARD

期刊论文

Improved rate-based modeling of carbon dioxide absorption with aqueous monoethanolamine solution

Stefania MOIOLI, Laura A. PELLEGRINI, Simone GAMBA, Ben LI

期刊论文

classification using Chinese advanced high-resolution satellite imagery and an object-oriented multi-variablemodel

Li-gang MA,Jin-song DENG,Huai YANG,Yang HONG,Ke WANG

期刊论文

Simulation of cohesive crack growth by a variable-node XFEM

Weihua FANG, Jiangfei WU, Tiantang YU, Thanh-Tung NGUYEN, Tinh Quoc BUI

期刊论文

Modification of the activated sludge model for chemical dosage

Shuai MA,Siyu ZENG,Xin DONG,Jining CHEN,Gustaf OLSSON

期刊论文

Evaluation of measurement uncertainty of the high-speed variable-slit system based on the Monte Carlo

Yin ZHANG, Jianwei WU, Kunpeng XING, Zhongpu WEN, Jiubin TAN

期刊论文

Mechanical design, modeling, and identification for a novel antagonistic variable stiffness dexterous

期刊论文

一种基于高斯过程与粒子群算法的CNN超参数自动搜索混合模型优化算法

闫涵,仲崇权,吴玉虎,张立勇,卢伟

期刊论文

Variable stiffness and damping magnetorheological isolator

Yang ZHOU, Xingyu WANG, Xianzhou ZHANG, Weihua LI

期刊论文