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Real-time immune-inspired optimum state-of-charge trajectory estimation using upcoming route information

Ahmad MOZAFFARI,Mahyar VAJEDI,Nasser L. AZAD

《机械工程前沿（英文）》 2015年 第10卷 第2期   页码 154-167 doi: 10.1007/s11465-015-0336-z

摘要：

The main proposition of the current investigation is to develop a computational intelligence-based framework which can be used for the real-time estimation of optimum battery state-of-charge (SOC) trajectory in plug-in hybrid electric vehicles (PHEVs). The estimated SOC trajectory can be then employed for an intelligent power management to significantly improve the fuel economy of the vehicle. The devised intelligent SOC trajectory builder takes advantage of the upcoming route information preview to achieve the lowest possible total cost of electricity and fossil fuel. To reduce the complexity of real-time optimization, the authors propose an immune system-based clustering approach which allows categorizing the route information into a predefined number of segments. The intelligent real-time optimizer is also inspired on the basis of interactions in biological immune systems, and is called artificial immune algorithm (AIA). The objective function of the optimizer is derived from a computationally efficient artificial neural network (ANN) which is trained by a database obtained from a high-fidelity model of the vehicle built in the Autonomie software. The simulation results demonstrate that the integration of immune inspired clustering tool, AIA and ANN, will result in a powerful framework which can generate a near global optimum SOC trajectory for the baseline vehicle, that is, the Toyota Prius PHEV. The outcomes of the current investigation prove that by taking advantage of intelligent approaches, it is possible to design a computationally efficient and powerful SOC trajectory builder for the intelligent power management of PHEVs.

关键词： trip information preview     intelligent transportation     state-of-charge trajectory builder     immune systems     artificial neural network    

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真实空气中TNT装药爆炸近区冲击波传播特性研究

周丰峻,郑磊,孙云厚,张鏖,夏明

《中国工程科学》 2017年 第19卷 第6期   页码 18-26 doi: 10.15302/J-SSCAE-2017.06.004

摘要：

本文基于点源爆炸理论，建立了面源、线源和点源TNT装药强爆炸解，填补了面源与线源强爆炸解的空白；采用真实空气状态方程进行分析计算，研究了真实空气条件下球形TNT装药爆炸近区冲击波的传播特性。通过算例分析，计算结果与已有文献资料数据吻合较好。本文的研究成果对爆炸力学和防护工程研究起到了重要的参考作用。

关键词： TNT装药爆炸     真实空气状态方程     面源装药     线源装药     点源装药     抗爆防护    

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基于多模型融合驱动的锂离子动力电池荷电状态和容量联合估计研究 Article

熊瑞, 王榘, Weixiang Shen, 田金鹏, 穆浩

《工程（英文）》 2021年 第7卷 第10期   页码 1471-1484 doi: 10.1016/j.eng.2020.10.022

摘要：

锂离子动力电池（LIB）已成为各种电动载运工具的首选电源系统，包括电动汽车、电动轮船、电动火车和电动飞机。在全气候全寿命周期运行的电动载运工具中，锂离子电池的能量管理需要实时准确估计电池的荷电状态（SOC）和容量。本文提出了一种多阶段模型融合算法可协同估计SOC和容量。首先，基于正态分布假设，利用模型在不同老化状态下的残差均值和方差计算权重，建立参数稳定的融合模型。其次，将具有预测性的微分增益引入比例-积分观测器（PIO）以提高收敛速度。再次，将多阶段融合模型与比例-积分-微分观测器（PIDO）结合，建立了一种融合算法，可实现复杂应用环境下SOC和容量的协同估计。然后，讨论了融合算法的收敛性和抗噪性能。最后，搭建硬件在环平台，验证了融合算法的性能。不同老化状态和温度下的验证结果表明，融合算法可以实现SOC和容量的高精度协同估计，误差分别在2%和3.3%以内。

关键词： 荷电状态     容量估计     模型融合     比例-积分-微分观测器     硬件在环    

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Multiobjective trajectory optimization of intelligent electro-hydraulic shovel

《机械工程前沿（英文）》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0706-2

摘要： Multiobjective trajectory planning is still face challenges due to certain practical requirements and multiple contradicting objectives optimized simultaneously. In this paper, a multiobjective trajectory optimization approach that sets energy consumption, execution time, and excavation volume as the objective functions is presented for the electro-hydraulic shovel (EHS). The proposed cubic polynomial S-curve is employed to plan the crowd and hoist speed of EHS. Then, a novel hybrid constrained multiobjective evolutionary algorithm based on decomposition is proposed to deal with this constrained multiobjective optimization problem. The normalization of objectives is introduced to minimize the unfavorable effect of orders of magnitude. A novel hybrid constraint handling approach based on -constraint and the adaptive penalty function method is utilized to discover infeasible solution information and improve population diversity. Finally, the entropy weight technique for order preference by similarity to an ideal solution method is used to select the most satisfied solution from the Pareto optimal set. The performance of the proposed strategy is validated and analyzed by a series of simulation and experimental studies. Results show that the proposed approach can provide the high-quality Pareto optimal solutions and outperforms other trajectory optimization schemes investigated in this article.

关键词： trajectory planning     electro-hydraulic shovel     cubic polynomial S-curve     multiobjective optimization     entropy weight technique    

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Charge-carrier photogeneration and extraction dynamics of polymer solar cells probed by a transient photocurrentnearby the regime of the space charge-limited current

Boa Jin, Hyunmin Park, Yang Liu, Leijing Liu, Jongdeok An, Wenjing Tian, Chan Im

《化学科学与工程前沿（英文）》 2021年 第15卷 第1期   页码 164-179 doi: 10.1007/s11705-020-1976-z

摘要： To understand the complex behaviors of photogenerated charge carriers within polymer-based bulk-heterojunction-type solar cells, the charge-carrier photogeneration and extraction dynamics are simultaneously estimated using a transient photocurrent technique under various external-bias voltages, and a wide range of excitation intensities are analyzed. For this purpose, conventional devices with 80 nm thick active layers consisting of a blend of representative P3HT and PTB7 electron-donating polymers and proper electron-accepting fullerene derivatives were used. After the correction for the saturation behavior at a high excitation-intensity range nearby the regime of the space charge-limited current, the incident-photon-density-dependent maximum photocurrent densities at the initial peaks are discussed as the proportional measures of the charge-carrier-photogeneration facility. By comparing the total number of the extracted charge carriers to the total number of the incident photons and the number of the initially photogenerated charge carriers, the external quantum efficiencies as well as the extraction quantum efficiencies of the charge-carrier collection during a laser-pulse-induced transient photocurrent process were obtained. Subsequently, the charge-carrier concentration-dependent mobility values were obtained, and they are discussed in consideration of the additional influences of the charge-carrier losses from the device during the charge-carrier extraction that also affects the photocurrent-trace shape.

关键词： charge-carrier photogeneration     transient photocurrent     polymer solar cells     charge-carrier extraction     space charge-limited current    

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Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework

《结构与土木工程前沿（英文）》   页码 994-1010 doi: 10.1007/s11709-023-0942-5

摘要： The moving trajectory of the pipe-jacking machine (PJM), which primarily determines the end quality of jacked tunnels, must be controlled strictly during the entire jacking process. Developing prediction models to support drivers in performing rectifications in advance can effectively avoid considerable trajectory deviations from the designed jacking axis. Hence, a gated recurrent unit (GRU)-based deep learning framework is proposed herein to dynamically predict the moving trajectory of the PJM. In this framework, operational data are first extracted from a data acquisition system; subsequently, they are preprocessed and used to establish GRU-based multivariate multistep-ahead direct prediction models. To verify the performance of the proposed framework, a case study of a large pipe-jacking project in Shanghai and comparisons with other conventional models (i.e., long short-term memory (LSTM) network and recurrent neural network (RNN)) are conducted. In addition, the effects of the activation function and input time-step length on the prediction performance of the proposed framework are investigated and discussed. The results show that the proposed framework can dynamically and precisely predict the PJM moving trajectory during the pipe-jacking process, with a minimum mean absolute error and root mean squared error (RMSE) of 0.1904 and 0.5011 mm, respectively. The RMSE of the GRU-based models is lower than those of the LSTM- and RNN-based models by 21.46% and 46.40% at the maximum, respectively. The proposed framework is expected to provide an effective decision support for moving trajectory control and serve as a foundation for the application of deep learning in the automatic control of pipe jacking.

关键词： dynamic prediction     moving trajectory     pipe jacking     GRU     deep learning    

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Research on Anthropomorphic Obstacle Avoidance Trajectory Planning for Adaptive Driving Scenarios Based

Jian Wu,Yang Yan,Yulong Liu,Yahui Liu,

《工程（英文）》 doi: 10.1016/j.eng.2023.07.018

摘要： The forward design of trajectory planning strategies requires preset trajectory optimization functions, resulting in poor adaptability of the strategy and an inability to accurately generate obstacle avoidance trajectories that conform to real driver behavior habits. In addition, owing to the strong time-varying dynamic characteristics of obstacle avoidance scenarios, it is necessary to design numerous trajectory optimization functions and adjust the corresponding parameters. Therefore, an anthropomorphic obstacle-avoidance trajectory planning strategy for adaptive driving scenarios is proposed. First, numerous expert-demonstrated trajectories are extracted from the HighD natural driving dataset. Subsequently, a trajectory expectation feature-matching algorithm is proposed that uses maximum entropy inverse reinforcement learning theory to learn the extracted expert-demonstrated trajectories and achieve automatic acquisition of the optimization function of the expert-demonstrated trajectory. Furthermore, a mapping model is constructed by combining the key driving scenario information that affects vehicle obstacle avoidance with the weight of the optimization function, and an anthropomorphic obstacle avoidance trajectory planning strategy for adaptive driving scenarios is proposed. Finally, the proposed strategy is verified based on real driving scenarios. The results show that the strategy can adjust the weight distribution of the trajectory optimization function in real time according to the “emergency degree” of obstacle avoidance and the state of the vehicle. Moreover, this strategy can generate anthropomorphic trajectories that are similar to expert-demonstrated trajectories, effectively improving the adaptability and acceptability of trajectories in driving scenarios.

关键词： Obstacle avoidance trajectory planning     Inverse reinforcement theory     Anthropomorphic     Adaptive driving scenarios    

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Charge and separation characteristics of nanofiltration membrane embracing dissociated functional groups

Zhun MA,Meng WANG,Xueli GAO,Congjie GAO

《环境科学与工程前沿（英文）》 2014年 第8卷 第5期   页码 650-658 doi: 10.1007/s11783-013-0605-1

摘要： The current work focused on the investigation of charge and separation characteristics of nanofiltration (NF) membrane embracing dissociated functional groups under different electrolyte solutions. The electro-kinetic method was carried out to assess the membrane volume charge density ( ) with different salt concentrations ranging from 0.1 to 10 mol·m and different electrolyte species, such as type 1–1, type 2–1 and type 3–1. The Donnan steric pore model-dielectric exclusion (DSPM-DE) model was employed to evaluate the separation characteristics of the NF membrane for wide range of electrolyte concentration (from 25.7 to 598.9 mol·m ). The results indicated that the dissociation of the hydrophilic functional groups and the specific adsorption contributed to charge formation on membrane surface. The former played a dominant role in type 1–1 and type 2–1 electrolytes at dilute aqueous solutions (0.1–0.5 mol·m ). However, for type 3–1 electrolyte, specific adsorption should contribute to the charge effect to a large extent. Moreover, the correlation between the volume charge density and feed concentration was in accordance with Freundlich isotherm. Furthermore, it was found that the separation characteristic of NF membrane could be evaluated well by DSPM-DE model coupling with electro-kinetic method in a whole concentration range.

关键词： Sulfonated polyethersulfone nanofiltration membrane     charge characteristics     electro-kinetic method     volume charge density     separation behavior    

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Visible-light-driven heterostructured g-CN/Bi-TiO floating photocatalyst with enhanced charge carrier

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1417-3

摘要：

• Bi doping in TiO2 enhanced the separation of photo-generated electron-hole.

关键词： Bi doping     Visible light     Algal removal     Charge carrier separation    

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Robust train speed trajectory optimization: A stochastic constrained shortest path approach

Li WANG, Lixing YANG, Ziyou GAO, Yeran HUANG

《工程管理前沿（英文）》 2017年 第4卷 第4期   页码 408-417 doi: 10.15302/J-FEM-2017042

摘要： Train speed trajectory optimization is a significant issue in railway traffic systems, and it plays a key role in determining energy consumption and travel time of trains. Due to the complexity of real-world operational environments, a variety of factors can lead to the uncertainty in energy-consumption. To appropriately characterize the uncertainties and generate a robust speed trajectory, this study specifically proposes distance-speed networks over the inter-station and treats the uncertainty with respect to energy consumption as discrete sample-based random variables with correlation. The problem of interest is formulated as a stochastic constrained shortest path problem with travel time threshold constraints in which the expected total energy consumption is treated as the evaluation index. To generate an approximate optimal solution, a Lagrangian relaxation algorithm combined with dynamic programming algorithm is proposed to solve the optimal solutions. Numerical examples are implemented and analyzed to demonstrate the performance of proposed approaches.

关键词： train speed trajectory optimization     railway operation     stochastic programming    

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autonomous mining: design and development of an unmanned electric shovel via point cloud-based optimal trajectory

《机械工程前沿（英文）》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0686-2

摘要： With the proposal of intelligent mines, unmanned mining has become a research hotspot in recent years. In the field of autonomous excavation, environmental perception and excavation trajectory planning are two key issues because they have considerable influences on operation performance. In this study, an unmanned electric shovel (UES) is developed, and key robotization processes consisting of environment modeling and optimal excavation trajectory planning are presented. Initially, the point cloud of the material surface is collected and reconstructed by polynomial response surface (PRS) method. Then, by establishing the dynamical model of the UES, a point to point (PTP) excavation trajectory planning method is developed to improve both the mining efficiency and fill factor and to reduce the energy consumption. Based on optimal trajectory command, the UES performs autonomous excavation. The experimental results show that the proposed surface reconstruction method can accurately represent the material surface. On the basis of reconstructed surface, the PTP trajectory planning method rapidly obtains a reasonable mining trajectory with high fill factor and mining efficiency. Compared with the common excavation trajectory planning approaches, the proposed method tends to be more capable in terms of mining time and energy consumption, ensuring high-performance excavation of the UES in practical mining environment.

关键词： autonomous excavation     unmanned electric shovel     point cloud     excavation trajectory planning    

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Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI

Zhijun PENG ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 353-358 doi: 10.1007/s11708-009-0035-8

摘要： The influences of charge stratification on spark ignition (SI) engine combustion and NO emission were analyzed using a phenomenological model. The mixture in the cylinder was divided spherically into three parts: a central core with a stoichiometric air-fuel charge, a dilution region without any combustible charge, and a mixing region lying between the core and the dilution region. Three mixture stratification parameters such as the extent of dilution in the mixing region, the extent of combustible charge in the mixing region, and the gradient of stratification in the mixing region were investigated. The results indicate that the extent of combustible charge in the mixing region could reduce in-cylinder NO formation significantly, compared with the extent of dilution in the mixing region. As long as the degree of dilution in the mixing region is within the dilution limit of the combustible charge, the gradient of dilution has little effect on combustion and NO formation.

关键词： charge stratification     SI engine     lean-burn combustion     NO emission    

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A framework for stochastic estimation of electric vehicle charging behavior for risk assessment of distribution networks

Salman HABIB, Muhammad Mansoor KHAN, Farukh ABBAS, Muhammad NUMAN, Yaqoob ALI, Houjun TANG, Xuhui YAN

《能源前沿（英文）》 2020年 第14卷 第2期   页码 298-317 doi: 10.1007/s11708-019-0648-5

摘要： Power systems are being transformed to enhance the sustainability. This paper contributes to the knowledge regarding the operational process of future power networks by developing a realistic and stochastic charging model of electric vehicles (EVs).Large-scale integration of EVs into residential distribution networks (RDNs) is an evolving issue of paramount significance for utility operators. Unbalanced voltages prevent effective and reliable operation of RDNs. Diversified EV loads require a stochastic approach to predict EVs charging demand, consequently, a probabilistic model is developed to account several realistic aspects comprising charging time, battery capacity, driving mileage, state-of-charge, traveling frequency, charging power, and time-of-use mechanism under peak and off-peak charging strategies. An attempt is made to examine risks associated with RDNs by applying a stochastic model of EVs charging pattern. The output of EV stochastic model obtained from Monte-Carlo simulations is utilized to evaluate the power quality parameters of RDNs. The equipment capability of RDNs must be evaluated to determine the potential overloads. Performance specifications of RDNs including voltage unbalance factor, voltage behavior, domestic transformer limits and feeder losses are assessed in context to EV charging scenarios with various charging power levels at different penetration levels. Moreover, the impact assessment of EVs on RDNs is found to majorly rely on the type and location of a power network.

关键词： electric vehicles (EVs)     residential distribution networks (RDNs)     voltage unbalance factor (VUF)     state-of charge (SOC)     time-of-use (TOU)    

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membranes using SPES as a hydrophilic polymer for the effective removal of dyes via steric hindrance and charge

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1555-1567 doi: 10.1007/s11705-023-2338-4

摘要： Herein, polyethersulfone (PES) and sulfonated polysulfone (SPSf) blend membranes were prepared with addition of sulfonated polyethersulfone (SPES) as a hydrophilic polymer and adipic acid as a porogen via non-solvent induced phase separation method for effective fractionation of dyes based on the influence of steric hindrance and charge effect. Raman spectroscopy and molecular dynamic simulation modeling confirmed that hydrogen bonds between PES, SPSf, SPES, and adipic acid were crucial to membrane formation and spatial arrangement. Further addition of hydrophilic SPES resulted in a membrane with reduced pore size and molecular weight cut-off as well as amplified negative charge and pure water permeance. During separation, the blend membranes exhibited higher rejection rates for nine types of small molecular weight (269.3–800 Da) dyes than for neutral polyethylene glycol molecules (200–1000 Da). This was attributed to the size effect and the synergistic effect between steric hindrance and charge repulsion. Notably, the synergistic impact decreased with dye molecular weight, while greater membrane negative charge enhanced small molecular dye rejection. Ideal operational stability and anti-fouling performance were best observed in M2 (PES/SPSf/SPES, 3.1 wt %). Summarily, this study demonstrates that SPES with –SO3‒ functional groups can be applied to control the microstructure and separation of membranes.

关键词： adipic acid     loose nanofiltration membrane     dye/salt selective separation     steric hindrance     charge effect    

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General Optimal Trajectory Planning: Enabling Autonomous Vehicles with the Principle of Least Action

Heye Huang,Yicong Liu,Jinxin Liu,Qisong Yang,Jianqiang Wang,David Abbink,Arkady Zgonnikov,

《工程（英文）》 doi: 10.1016/j.eng.2023.10.001

摘要： This study presents a general optimal trajectory planning (GOTP) framework for autonomous vehicles (AVs) that can effectively avoid obstacles and guide AVs to complete driving tasks safely and efficiently. Firstly, we employ the fifth-order Bezier curve to generate and smooth the reference path along the road centerline. Cartesian coordinates are then transformed to achieve the curvature continuity of the generated curve. Considering the road constraints and vehicle dynamics, limited polynomial candidate trajectories are generated and smoothed in a curvilinear coordinate system. Furthermore, in selecting the optimal trajectory, we develop a unified and auto-tune objective function based on the principle of least action by employing AVs to simulate drivers’ behavior and summarizing their manipulation characteristics of “seeking benefits and avoiding losses.” Finally, by integrating the idea of receding-horizon optimization, the proposed framework is achieved by considering dynamic multi-performance objectives and selecting trajectories that satisfy feasibility, optimality, and adaptability. Extensive simulations and experiments are performed, and the results demonstrate the framework’s feasibility and effectiveness, which avoids both dynamic and static obstacles and applies to various scenarios with multi-source interactive traffic participants. Moreover, we prove that the proposed method can guarantee real-time planning and safety requirements compared to drivers’ manipulation.

关键词： Autonomous vehicle     Trajectory planning     Multi-performance objectives     Principle of least action    

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标题 作者 时间 类型 操作

Real-time immune-inspired optimum state-of-charge trajectory estimation using upcoming route information

Ahmad MOZAFFARI,Mahyar VAJEDI,Nasser L. AZAD

期刊论文

真实空气中TNT装药爆炸近区冲击波传播特性研究

周丰峻,郑磊,孙云厚,张鏖,夏明

期刊论文

基于多模型融合驱动的锂离子动力电池荷电状态和容量联合估计研究

熊瑞, 王榘, Weixiang Shen, 田金鹏, 穆浩

期刊论文

Multiobjective trajectory optimization of intelligent electro-hydraulic shovel

期刊论文

Charge-carrier photogeneration and extraction dynamics of polymer solar cells probed by a transient photocurrentnearby the regime of the space charge-limited current

Boa Jin, Hyunmin Park, Yang Liu, Leijing Liu, Jongdeok An, Wenjing Tian, Chan Im

期刊论文

Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework

期刊论文

Research on Anthropomorphic Obstacle Avoidance Trajectory Planning for Adaptive Driving Scenarios Based

Jian Wu,Yang Yan,Yulong Liu,Yahui Liu,

期刊论文

Charge and separation characteristics of nanofiltration membrane embracing dissociated functional groups

Zhun MA,Meng WANG,Xueli GAO,Congjie GAO

期刊论文

Visible-light-driven heterostructured g-CN/Bi-TiO floating photocatalyst with enhanced charge carrier

期刊论文

Robust train speed trajectory optimization: A stochastic constrained shortest path approach

Li WANG, Lixing YANG, Ziyou GAO, Yeran HUANG

期刊论文

autonomous mining: design and development of an unmanned electric shovel via point cloud-based optimal trajectory

期刊论文

Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI

Zhijun PENG ,

期刊论文

A framework for stochastic estimation of electric vehicle charging behavior for risk assessment of distribution networks

Salman HABIB, Muhammad Mansoor KHAN, Farukh ABBAS, Muhammad NUMAN, Yaqoob ALI, Houjun TANG, Xuhui YAN

期刊论文

membranes using SPES as a hydrophilic polymer for the effective removal of dyes via steric hindrance and charge

期刊论文

General Optimal Trajectory Planning: Enabling Autonomous Vehicles with the Principle of Least Action

Heye Huang,Yicong Liu,Jinxin Liu,Qisong Yang,Jianqiang Wang,David Abbink,Arkady Zgonnikov,

期刊论文