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Progress review of US-China joint research on advanced technologies for plug-in electric vehicles

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Science China(Technological Sciences) 2018年第10期61卷 1431-1445页

作者： OUYANG MingGao DU JiuYu PENG huei WANG HeWu FENG XuNing SONG ZiYou State Key Laboratory of Automotive Safety and Energy Tsinghua University University of Michigan Mechanical Engineering

The United States and China are the world's largest automobile markets and oil consumers, and both face a severe challenge to conserve energy and reduce tailpipe emissions. Thus, both countries urgently need to transform conventional internal combustion engines to electrified powertrains. Targeting the advanced core technologies of plug-in electric vehicles(PEVs), a joint research collaboration between China and the US, called the "Clean Vehicle Consortium"(CVC), was set up in 2010. Six years of collaboration on PEV technologies has resulted in significant progress in three technical areas. Based on CVC publications,we review herein the progress made by the CVC research efforts on three key advanced PEV technologies. This includes the development of a safe battery with an energy density of 260 W h kg^(-1) and a systematic method for designing safe traction battery systems. Thus, a breakthrough in high power density and efficient traction motor systems has occurred. In addition to discussing advanced electric-drive powertrains, we also discuss global energy management strategies that aim to improve PEV energy efficiency. This discussion covers scientific and comprehensive analysis methods to analyze energy systems, which include costbenefit analyses of plug-in hybrid electric vehicles, life-cycle assessments for evaluating vehicle emissions, and PEV-ownership projections.

关键词： US-China joint research plug-in electric vehicle safety of traction battery electric driving powertrain energy system analysis

Organic matter and concentrated nitrogen removal by shortcut nitrification and denitrification from mature municipal landfill leachate

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Journal of Environmental Sciences 2007年第6期19卷 647-651页

作者： ZHANG shu-jun PENG Yong-zhen WANG shu-ying ZHENG shu-wen GUO Jin College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

An UASB＋Anoxic/Oxic （A/O） system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leaehate, the denitrifieation of NOx^--N in the reeireulation effluent from the elarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrifieation in the UASB. The NH4^＋-N loading rate （ALR） of A/O reactor and operational temperature was 0.28- 0.60 kg NH4^＋-N/（m^3-d） and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4^＋-N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4^＋-N/（m^3.d）, the NH4^＋-N removal efficiency was more than 98%. With the influent NH4^＋-N of 1200-1800 mg/L, the effluent NH4^＋-N was less than 15 mg/L. The shortcut nitrification and denitrifieation can save 40% carbon source, with a highly efficient denitrifieation taking place in the UASB. When the ratio of the feed COD to feed NH4^＋-N was only 2-3, the total inorganic nitrogen （TIN） removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria （AOB） accounted for 4% of the total eubaeterial population, whereas nitrite oxidation bacteria （NOB） accounted only for 0.2% of the total eubaeterial population.

关键词： mature landfill leachate UASB+A/O shortcut nitrification carbon source

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基于LSTM模型的股票价格预测

江苏商论 2025年第1期 83-86页

作者：姜淑瑜湖北工业大学经济与管理学院湖北武汉430068

股票市场的价格波动被视为经济发展的晴雨表。对股票价格的精准预测一直是众多研究学者努力的方向。随着人工智能技术与大数据技术的不断应用与发展以及疫情防控期间国内经济变化和国际形势变换给股价带来的巨大波动,如何对股价进行精... 详细信息

股票市场的价格波动被视为经济发展的晴雨表。对股票价格的精准预测一直是众多研究学者努力的方向。随着人工智能技术与大数据技术的不断应用与发展以及疫情防控期间国内经济变化和国际形势变换给股价带来的巨大波动,如何对股价进行精准预测变得越来越重要。本文根据股票市场的特点和LSTM(Long Short-Term Memory)递归神经网络的特性,对浦发银行(600000)股价进行预测。实验结果表明,LSTM模型预测股价,结果误差小,精准度高,具有良好的预测效果。

关键词：股票价格预测 LSTM 机器学习神经网络

Roles of crystal defects in the persistent luminescence of Eu^(2+), Dy^(3+) co-doped strontium aluminate based phosphors

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Rare Metals 2007年第4期26卷 305-310页

作者： LU Xingdong shu Wangen School of Materials Jiangxi University of Finance and Economy Nanchang 330013 China College of Chemistry and Chemical Engineering Central South University Changsha 330013 China

The roles of different point defects in persistent luminescence of SrAl2O4：Eu,Dy phosphors were investigated. The research results showed that Dyer plays an important role in the persistent luminescence of SrA1EO4：Eu, Dy phosphors. It can serve as the electron trap of suitable depth for persistent luminescence. V~ does not serve as the electron trap of suitable depth, but its existence can increase the depth of electron traps. There is interaction between the Dy^3＋（ DySr ） and the Eu^2＋（Eu^x Sr ）, and only if the distance between the Dy^3＋（DySr） and the Eu^2＋（Eu^x Sr） is close enough, the Dyer can work as an effective electron trap. The point defect of V＂ Sr can be hole trap, but the change of its density in crystal matrix does not arouse the obvious change of persistent luminescence.

关键词： inorganic non-metal material strontium aluminate persistent luminescence rare earth ions point defect

Maximum Principle for Partially-Observed Optimal Control Problems of Stochastic Delay Systems

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Journal of Systems Science & Complexity 2017年第2期30卷 316-328页

作者： WU shuang shu Lan School of Mathematical Sciences University of Electronic Science and Technology of China Department of Applied Mathematics China University of Petroleum

This paper is concerned with partially-observed optimal control problems for stochastic delay systems. Combining Girsanov's theorem with a standard variational technique, the authors obtain a maximum principle on the assumption that the system equation contains time delay and the control domain is convex. The related adjoint processes are characterized as solutions to anticipated backward stochastic differential equations in finite-dimensional spaces. Then, the proposed theoretical result is applied to study partially-observed linear-quadratic optimal control problem for stochastic delay system and an explicit observable control variable is given.

关键词： Anticipated backward stochastic differential equation maximum principle partially-observed optimal control stochastic delay systems.

Inverse Lyapunov Theorem for Linear Time Invariant Fractional Order Systems

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Journal of Systems Science & Complexity 2019年第6期32卷 1544-1559页

作者： LIANG shu LIANG Yinshan Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China Institute of Information Spreading Engineering Changchun University of TechnologyChangchun 130012China

This paper investigates the inverse Lyapunov theorem for linear time invariant fractional order *** is proved that given any stable linear time invariant fractional order system,there exists a positive definite functional with respect to the system state,and the first order time derivative of that functional is negative definite.A systematic procedure to construct such Lyapunov candidates is provided in terms of some Lyapunov functional equations.

关键词： Fractional order systems infinite-dimensional systems inverse Lyapunov theorem stability criterion

A Comprehensive Evaluation on Energy, Economic and Environmental Performance of the Trombe Wall during the Heating Season

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Journal of Thermal Science 2019年第6期28卷 1141-1149页

作者： ZHANG Hongliang shu Haiwen School of Civil Engineering Dalian University of Technology

Trombe wall is a passive building energy saving technology that uses solar energy to reduce buildings’ heating load and adjust indoor thermal environment. In recent years, much research has been done to increase the thermal efficiency of Trombe wall, but little is focused on the evaluation of Trombe wall from energy, economic and environmental aspects comprehensively. Based on the thermal performance calculation method in ISO 52016-2:2017(E), the authors proposed a concise method to evaluate the energy, economic and environmental performance of ventilated and non-ventilated Trombe walls during a heating season. Firstly, non-iteration calculation methods were introduced for the energy evaluation of Trombe wall and conventional wall during the heating season. Then the economic and environmental evaluation models were brought out according to the energy performance of Trombe wall. After that, a residential building was presented as the case building to evaluate Trombe walls’ performance in five building climate zones of China. The calculation results showed that both heating degree days and solar radiation had significant impact on the energy saving effect of Trombe walls. In comparison with non-ventilated Trombe walls, ventilated ones displayed more obvious energy saving potential in all five climate regions, which can provide averagely 62% more heating for the room in the case study. Though the heating degree days of Guangzhou(hot-summer and warm-winter zone) was the smallest in the five zones, ventilated Trombe wall in the zone had the poorest economic performance due to the scarcest solar radiation during the heating season.

关键词： Trombe wall energy evaluation economic evaluation environmental evaluation heating load

Uranyl oxamate hydrates: hydrothermal synthesis, crystal structure, photophysical properties, and selective crystallization

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Science China Chemistry 2016年第6期59卷 740-745页

作者： Yubo shu Weisheng Liu College of Chemistry and Chemical Engineering Lanzhou University School of Chemical and Biological Engineering Hechi University

Presented here are two isostructural uranyl coordination polymers [UOe（EDO）（H2O）]· H2O （1） and [UO2（BDO）（H2O）]-2H2O （2）（EDO2---ethylene-1,2-dioxamate; BDO2 =butylene-1,2-dioxamate） with identical stepwise zigzag chain structure and distinct interchain hydrogen bonding interaction, prepared from hydrothermal reaction of DEEDO or DEBDO （DEEDO- diethyl ethylene-1,2-dioxamate; DEBDO--diethyl butylene-l,2-dioxamate） with uranyl ions. The monomeric uranyl-based fluorescence emissions of compounds 1 and 2 are red-shifted by about 6 and 5 nm respectively, compared to that of uranyl nitrate hexahydrate. Compound 1 has stronger emission than compound 2, but both their emissions exhibit triple-exponential decay. The photophysics of uranyl oxalate trihydrate was also investigated for comparison. The selective crystallization of compound 1 in alkaline solution was applied to the sequestration of uranyl ions, showing a kinetic preference.

关键词： uranium oxamate hydrothermal synthesis photophysics selective crystallization

A practical method in calculating one loop quantum fluctuations to the energy of the non-topological soliton

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 65-68页

作者： Song shu Department of Physics and Electronic Science Hubei University Wuhan 430062 China Department of Physics and Astronomy Stony Brook University New York 11794 USA

Non-topological soliton models which are effective models inspired from the underlying QCD theory are phenomenologically successful in describing the low energy nuclear physics. However, the main calculation methods in these models are based on mean field approximation, in other words treating the fields classically [1-4]. The quantum corrections in the background fields of spatially non-trivial con- figurations are very difficult to calculate. This is partly due to the fact that these calculations are nonlocal. During the past decades different calculation methods and approximate schemes have been developed on this problem [5-12]. As the calculation of quantum corrections of solitons is much more complex than those usual calculations of quantum loop corrections of trivial background fields, most studies on this problem are based on the derivative expansion method [5-9]. The renormalization in this method is a very nontrivial task.

关键词： QCD