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Two-phase early prediction method for remaining useful life of lithium-ion batteries based on a neural network and Gaussian process regression

《能源前沿(英文)》 doi: 10.1007/s11708-023-0906-4

摘要: Lithium-ion batteries (LIBs) are widely used in transportation, energy storage, and other fields. The prediction of the remaining useful life (RUL) of lithium batteries not only provides a reference for health management but also serves as a basis for assessing the residual value of the battery. In order to improve the prediction accuracy of the RUL of LIBs, a two-phase RUL early prediction method combining neural network and Gaussian process regression (GPR) is proposed. In the initial phase, the features related to the capacity degradation of LIBs are utilized to train the neural network model, which is used to predict the initial cycle lifetime of 124 LIBs. The Pearson coefficient’s two most significant characteristic factors and the predicted normalized lifetime form a 3D space. The Euclidean distance between the test dataset and each cell in the training dataset and validation dataset is calculated, and the shortest distance is considered to have a similar degradation pattern, which is used to determine the initial Dual Exponential Model (DEM). In the second phase, GPR uses the DEM as the initial parameter to predict each test set’s early RUL (ERUL). By testing four batteries under different working conditions, the RMSE of all capacity estimation is less than 1.2%, and the accuracy percentage (AP) of remaining life prediction is more than 98%. Experiments show that the method does not need human intervention and has high prediction accuracy.

关键词: lithium-ion batteries     RUL prediction     double exponential model     neural network     Gaussian process regression (GPR)    

General closed-form inverse kinematics for arbitrary three-joint subproblems based on the product of exponentialmodel

《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0681-7

摘要: The inverse kinematics problems of robots are usually decomposed into several Paden–Kahan subproblems based on the product of exponential model. However, the simple combination of subproblems cannot solve all the inverse kinematics problems, and there is no common approach to solve arbitrary three-joint subproblems in an arbitrary postural relationship. The novel algebraic geometric (NAG) methods that obtain the general closed-form inverse kinematics for all types of three-joint subproblems are presented in this paper. The geometric and algebraic constraints are used as the conditions precedent to solve the inverse kinematics of three-joint subproblems. The NAG methods can be applied in the inverse kinematics of three-joint subproblems in an arbitrary postural relationship. The inverse kinematics simulations of all three-joint subproblems are implemented, and simulation results indicating that the inverse solutions are consistent with the given joint angles validate the general closed-form inverse kinematics. Huaque III minimally invasive surgical robot is used as the experimental platform for the simulation, and a master–slave tracking experiment is conducted to verify the NAG methods. The simulation result shows the inverse solutions and six sets given joint angles are consistent. Additionally, the mean and maximum of the master–slave tracking experiment for the closed-form solution are 0.1486 and 0.4777 mm, respectively, while the mean and maximum of the master–slave tracking experiment for the compensation method are 0.3188 and 0.6394 mm, respectively. The experiments results demonstrate that the closed-form solution is superior to the compensation method. The results verify the proposed general closed-form inverse kinematics based on the NAG methods.

关键词: inverse kinematics     Paden–Kahan subproblems     three-joint subproblems     product of exponential     closed-form solution    

指数多项式均匀样条模型

赵颜利,平萍,刘凤玉

《中国工程科学》 2008年 第10卷 第7期   页码 147-152

摘要:

给出了k( k ≥ 3) 阶指数多项式的均匀样条模型。该类模型具有很多与B 样条模型相同的性质,并 且增加了一个可调节的形状参数。由该模型构造的曲线,通过改变形状参数的取值,可以调整曲线接近其控 制多边形的程度。应用于CAD/CAM领域,可作为几何造型的一种新的有效模型。

关键词: 指数多项式样条函数     B样条函数     形状参数    

Reaction kinetics of CaC

Renxing Wang,Zhenyu Liu,Leiming Ji,Xiaojin Guo,Xi Lin,Junfei Wu,Qingya Liu

《化学科学与工程前沿(英文)》 2016年 第10卷 第4期   页码 517-525 doi: 10.1007/s11705-016-1585-z

摘要: The production of CaC from coke/lime powders and compressed powder pellets are low cost and fast processes. A number of studies have reported the reaction kinetics of these reactions but they are still not well understood and the proposed kinetic models are not comparable due to differences in the reaction conditions. Therefore the reaction behavior of CaO/C powders (0.074 mm) and cubes (5 mm × 5 mm × (4.6–5.1) mm) compressed from a mixture of powders have been studied using thermal gravimetric analysis (TGA) at 1700– 1850 °C. Kinetic models were obtained from the TGA data using isoconversional and model-fitting methods. The reaction rates for the compressed feeds were lower than those for the powder feeds. This is due to the reduced surface area of the compressed samples which inhibits heat transfer from the surrounding environment (or the heating source) to the sample. The compression pressure had little influence on the reaction rate. The reaction kinetics of both the powder and the compressed feeds can be described by the contracting volume model ( ) = 3(1− ) , where is the conversion rate of reactant. The apparent activation energy and pre-exponential factor of the powder feed were estimated to 346–354 kJ?mol and 5.9 × 10 min , respectively, whereas those of the compressed feed were 305–327 kJ?mol and 3.6 × 10 min , respectively.

关键词: calcium carbide     kinetic model     activation energy     pre-exponential factor    

Determining the optimum economic insulation thickness of double pipes buried in the soil for district

Fating LI, Pengfei JIE, Zhou FANG, Zhimei WEN

《能源前沿(英文)》 2021年 第15卷 第1期   页码 170-185 doi: 10.1007/s11708-020-0680-5

摘要: The insulation thickness (IT) of double pipes buried in the soil (DPBIS) for district heating (DH) systems was optimized to minimize the annual total cost of DPBIS for DH systems. An optimization model to obtain the optimum insulation thickness (OIT) and minimum annual total cost (MATC) of DPBIS for DH systems was established. The zero point theorem and fsolve function were used to solve the optimization model. Three types of heat sources, four operating strategies, three kinds of insulation materials, three buried depth (BD) values, and seven nominal pipe size (NPS) values were considered in the calculation of the OIT and MATC of DPBIS for DH systems, respectively. The optimization results for the above factors were compared. The results show that the OIT and MATC of DPBIS for DH systems can be obtained by using the optimization model. Sensitivity analysis was conducted to investigate the impact of some economic parameters, i.e., unit heating cost, insulation material price, interest rate, and insulation material lifetime, on optimization results. It is found out that the impact of sensitivity factors on the OIT and MATC of DPBIS for DH systems is different.

关键词: double pipes     optimization model     optimum insulation thickness     minimum annual total cost    

指数型粘度修正模型及应用

曲庆文,王梅,柴山,姚福生

《中国工程科学》 2001年 第3卷 第10期   页码 53-58

摘要:

根据吸附理论和分子间能量的变化规律来确定表面相互作用程度,以此可定义吸附层,得出吸附层 厚度的分析计算式。吸附层厚度对研究薄膜润滑是最关键的因素,是薄膜与厚膜不同分析的关键点。根据分子 相互作用的基本理论及流体力学的基本定义得出指数型粘度修正的表达式,用于确定微小间隙内流体粘度的变 化规律,从而建立薄膜润滑理论模型,计算薄膜润滑轴承的特性。

关键词: 吸附层     粘度     薄膜润滑     轴承    

Ultrasonic linear motor using the L-B mode Langevin transducer with an exponential horn

SHI Shengjun, CHEN Weishan, LIU Junkao, ZHAO Xuetao

《机械工程前沿(英文)》 2008年 第3卷 第2期   页码 212-217 doi: 10.1007/s11465-008-0026-1

摘要: An ultrasonic linear motor is proposed and fabricated by using the longitudinal and bending vibration double mode bolt-clamped Langevin type transducer to meet high power and speed requirements in the aerospace and semiconductor ind

关键词: longitudinal     vibration     bolt-clamped     semiconductor     ultrasonic    

Optimal design of double-layer barrel vaults using genetic and pattern search algorithms and optimizedneural network as surrogate model

《结构与土木工程前沿(英文)》 2023年 第17卷 第3期   页码 378-395 doi: 10.1007/s11709-022-0899-9

摘要: This paper presents a combined method based on optimized neural networks and optimization algorithms to solve structural optimization problems. The main idea is to utilize an optimized artificial neural network (OANN) as a surrogate model to reduce the number of computations for structural analysis. First, the OANN is trained appropriately. Subsequently, the main optimization problem is solved using the OANN and a population-based algorithm. The algorithms considered in this step are the arithmetic optimization algorithm (AOA) and genetic algorithm (GA). Finally, the abovementioned problem is solved using the optimal point obtained from the previous step and the pattern search (PS) algorithm. To evaluate the performance of the proposed method, two numerical examples are considered. In the first example, the performance of two algorithms, OANN + AOA + PS and OANN + GA + PS, is investigated. Using the GA reduces the elapsed time by approximately 50% compared with using the AOA. Results show that both the OANN + GA + PS and OANN + AOA + PS algorithms perform well in solving structural optimization problems and achieve the same optimal design. However, the OANN + GA + PS algorithm requires significantly fewer function evaluations to achieve the same accuracy as the OANN + AOA + PS algorithm.

关键词: optimization     surrogate models     artificial neural network     SAP2000     genetic algorithm    

应用指数平滑技术预测边坡位移

沈良峰

《中国工程科学》 2007年 第9卷 第6期   页码 94-97

摘要:

应用趋势型指数平滑模型根据其观测值的数据特点(具线性趋势),选取趋势型二次指数平滑的线性 预测公式和相应at,bt的计算公式及合适的平滑系数值进行计算,预测了某市滑坡区5号监测点的位移量。预 测结果表明,该方法应用于斜坡变形位移的预测,可使预测值与实际位移值之间的误差很小。

关键词: 指数平滑     预测边坡位移     自适应过滤    

基于Web服务的分布式仿真系统的双重访问控制

陈学勤,吴慧中,朱耀琴

《中国工程科学》 2009年 第11卷 第8期   页码 72-78

摘要:

随着分布式仿真系统与Web服务技术的结合日益紧密,以及功能与资源分离的愈加明显,导致大量仿真资源暴露于网络中,传统、单一的访问控制模型已无法应对。为此提出了一种基于属性的针对功能和资源的双重访问控制模型,采用证书代理机制实现功能端单点登录,采用XACML实现资源端多属性的访问控制。详细描述了该模型的访问控制流程,目前已应用到虚拟采办系统中。通过对性能的分析和测试,证明了该双重访问控制模型的可用性和有效性。

关键词: Web服务安全     双重访问控制     分布式仿真系统    

采用线性和非线性拟合方法进行指数模型参数估计 Article

Ping YANG,Chao-peng WU,Yi-lu GUO,Hong-bo LIU,Hui HUANG,Hang-zhou WANG,Shu-yue ZHAN,Bang-yi TAO,Quan-quan MU,Qiang WANG,Hong SONG

《信息与电子工程前沿(英文)》 2017年 第18卷 第3期   页码 434-444 doi: 10.1631/FITEE.1601683

摘要: 本文探讨了通过线性和非线性拟合方法估计指数模型中的未知参数。基于多元函数极值定理及泰勒级数展开,从理论上证明了:在实验测量数据中包含噪声的情况下,通过线性拟合方法所得到的参数估计值并不能保证指数模型的残差平方和达到最小。通过数值仿真对线性和非线性拟合方法的结果进行了对比,仿真结果显示:线性方法只能获得未知参数的次优估计,但非线性方法给出更准确的结果。利用水下图像和成像距离数据对水体光谱衰减系数进行了估计,结果证实非线性拟合方法能够对参数估计准确度有明显的提升。

关键词: 指数模型;参数估计;线性最小二乘法;非线性拟合    

Minimization of total energy consumption in an m-machine flow shop with an exponential time-dependent

Lingxuan LIU, Zhongshun SHI, Leyuan SHI

《工程管理前沿(英文)》 2018年 第5卷 第4期   页码 487-498 doi: 10.15302/J-FEM-2018042

摘要:

This study investigates an energy-aware flow shop scheduling problem with a time-dependent learning effect. The relationship between the traditional and the proposed scheduling problem is shown and objective is to determine a job sequence in which the total energy consumption is minimized. To provide an efficient solution framework, composite lower bounds are proposed to be used in a solution approach with the name of Bounds-based Nested Partition (BBNP). A worst-case analysis on shortest process time heuristic is conducted for theoretical measurement. Computational experiments are performed on randomly generated test instances to evaluate the proposed algorithms. Results show that BBNP has better performance than conventional heuristics and provides considerable computational advantage.

关键词: flow shop     energy-aware scheduling     learning effect     nested partition     worst-case error bound    

Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

《结构与土木工程前沿(英文)》 2007年 第1卷 第4期   页码 448-457 doi: 10.1007/s11709-007-0061-8

摘要: The double- fracture model can well describe the development of cracks undergoing during the entire fracture process in concrete. Therefore, it has been selected as the theoretical basis of the Norm for fracture test of

关键词: development     concrete     theoretical     double- fracture    

Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

《能源前沿(英文)》 2021年 第15卷 第1期   页码 222-234 doi: 10.1007/s11708-017-0480-8

摘要: Architectural shade is an effective method for improving building energy efficiency. A new shade combined with the double skin façade (DSF) system, called middle shade (MS), was introduced and developed for buildings. In this paper, a 3D dynamic simulation was conducted to analyze the influence of MS combined with DSF on the indoor thermal characteristics. The research on MS for DSF involves the temperature, the ventilation rate, the velocity distribution of the air flow duct, and the indoor temperature. The results show that the angle and position of the shade in the three seasons are different, and different conditions effectively enhance the indoor thermal characteristics. In summer, the appearance of MS in DSF makes the indoor temperature significantly lower. The indoor temperature is obviously lower than that of the air flow duct, and the temperature of the air flow duct is less affected by MS. The influence of the position of blinds on indoor temperature and ventilation rate is greater than the influence of the angle of blinds. According to the climate characteristics of winter and transition season, in winter, early spring, and late autumn, the indoor temperature decreases with the increase of the position of blinds at daytime, but the opposite is true at night. The results found in this paper can provide reference for the design and use of MS combined with DSF in hot summer and cold winter zone.

关键词: middle shade     position     thermal characteristics     double skin facade    

Moment-curvature relationship of FRP-concrete-steel double-skin tubular members

Mingxue LIU, Jiaru QIAN

《结构与土木工程前沿(英文)》 2009年 第3卷 第1期   页码 25-31 doi: 10.1007/s11709-009-0012-7

摘要: Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer (FRP)-concrete-steel double-skin tubular members (DSTMs). The strip method was used to calculate the section moment-curvature curves of the 3 specimens and 12 models. A theoretical formula is presented for the flexural strength of DSTMs. The test results show that the tension zone of the specimen FRP tubes was in hoop compression while the compression zone was in hoop tension. The load-carrying capacity did not decrease even when the mid-span deflection reached about 1/24 of the span length. The tests, simulation and theoretical analysis resulted in a simplified formula for the flexural strength of DSTMs and a tri-linear moment-curvature model was expressed as a function of the section bending stiffness for DSTMs.

关键词: fiber reinforced polymer (FRP)     concrete     steel     double-skin tubular members (DSTMs)     moment-curvature curve     flexural strength    

标题 作者 时间 类型 操作

Two-phase early prediction method for remaining useful life of lithium-ion batteries based on a neural network and Gaussian process regression

期刊论文

General closed-form inverse kinematics for arbitrary three-joint subproblems based on the product of exponentialmodel

期刊论文

指数多项式均匀样条模型

赵颜利,平萍,刘凤玉

期刊论文

Reaction kinetics of CaC

Renxing Wang,Zhenyu Liu,Leiming Ji,Xiaojin Guo,Xi Lin,Junfei Wu,Qingya Liu

期刊论文

Determining the optimum economic insulation thickness of double pipes buried in the soil for district

Fating LI, Pengfei JIE, Zhou FANG, Zhimei WEN

期刊论文

指数型粘度修正模型及应用

曲庆文,王梅,柴山,姚福生

期刊论文

Ultrasonic linear motor using the L-B mode Langevin transducer with an exponential horn

SHI Shengjun, CHEN Weishan, LIU Junkao, ZHAO Xuetao

期刊论文

Optimal design of double-layer barrel vaults using genetic and pattern search algorithms and optimizedneural network as surrogate model

期刊论文

应用指数平滑技术预测边坡位移

沈良峰

期刊论文

基于Web服务的分布式仿真系统的双重访问控制

陈学勤,吴慧中,朱耀琴

期刊论文

采用线性和非线性拟合方法进行指数模型参数估计

Ping YANG,Chao-peng WU,Yi-lu GUO,Hong-bo LIU,Hui HUANG,Hang-zhou WANG,Shu-yue ZHAN,Bang-yi TAO,Quan-quan MU,Qiang WANG,Hong SONG

期刊论文

Minimization of total energy consumption in an m-machine flow shop with an exponential time-dependent

Lingxuan LIU, Zhongshun SHI, Leyuan SHI

期刊论文

Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

期刊论文

Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

期刊论文

Moment-curvature relationship of FRP-concrete-steel double-skin tubular members

Mingxue LIU, Jiaru QIAN

期刊论文