High-Power and Ultralong-Life Aqueous Zinc-Ion Hybrid Capacitors Based on Pseudocapacitive Charge Storage

Rechargeable aqueous zinc-ion hybrid capacitors and zincion batteries are promising safe energy storage systems.In this study,amorphous RuO2·H2O for the first time was employed to achieve fast and ultralong-life Zn2+storage based on a pseudocapacitive storage mechanism.In the RuO2·H2O||Zn zinc-ion hybrid capacitors with Zn(CF3SO3)2 aqueous electrolyte,the RuO2·H2O cathode can reversibly store Zn2+in a voltage window of 0.4-1.6 V(vs.Zn/Zn2+),delivering a high discharge capacity of 122 mAh g?1.In particular,the zinc-ion hybrid capacitors can be rapidly charged/discharged within 36 s with a very high power density of 16.74 kW kg?1 and a high energy density of 82 Wh kg?1.Besides,the zinc-ion hybrid capacitors demonstrate an ultralong cycle life(over 10,000 charge/discharge cycles).The kinetic analysis elucidates that the ultrafast Zn2+storage in the RuO2·H2O cathode originates from redox pseudocapacitive reactions.This work could greatly facilitate the development of high-power and safe electrochemical energy storage.

Probabilistic Analysis of Life Cycle Cost for Power Transformer

The selection of power transformer is very important to power sector. Most methods are utilized according to the initial cost and don’t consider the synthetical evaluation of economy and technology. Based on previous research, this paper addresses a new practical probabilistic life cycle cost model. Then, in order to demonstrate the practicability of probabilistic life cycle cost for the power transformer, illustrative investment alternatives of actual power transformers are discussed. From the result of the numerical investigation, it may be positively stated that the optimum investment alternative for the power transformer based on the probabilistic life cycle cost model proposed in this study will lead to a more rational, economical and effective procedure compared with the conventional method only considering the initial cost.

Power Relation in A Life in the Theatre

As a noted modern American playwright, David Mamet attracts wide attention from the readers, the audience, as well as the academic circle with his fascinating language features. In his plays, in order to achieve their individual goals, the male characters, applying the discursive power with language as weapon, endeavor to build a new structure of power. It aims to analyze A Life in the Theatre, with such discourse-analysis mechanics as turn-taking and politeness strategy, to examine the power relations between the two male characters in the play, and finally to explain how discourse influence and alter the power relations in reality.

Power Density and SAR in Multi-Layered Life Tissue at Global System Mobile (GSM) Frequencies

In this paper, the power density and specific absorption rate (SAR) distribution in multi-layered life tissues and exposed to electromagnetic field emitted from handheld cellular phone operating in the 900 MHz and 1800 MHz is studied. We modeled a life tissue by four layered system to represent skin-fat-muscles-organs respectively. Matlab program and finite difference time domain (FDTD) computations were used to evaluator the electric, magnetic field, power density and specific absorption rate. A one dimensional FDTD algorithm has been built, some simulations for electromagnetic wave through the life tissue is made. Results show that electro magnetic fields penetrate the life tissues and attenuate fast to reach zero at the organs layer. The absorbent power and SAR show maximum at the skin and fat layers.

LiFePO_(4)动力电池加速循环寿命实验研究

针对LiFePO_(4)动力电池循环寿命评估周期长,成本高的问题,设计了以充电倍率、放电倍率、环境测试温度以及多因素耦合为测试条件的加速循环容量衰退实验。实验表明,充、放电倍率加速寿命能力随着电池温度的升高而提高。在环境测试温度为25~55℃时,温度升高具有明显的加速作用,进一步提高环境测试温度不再具有加速作用。该实验结果可为LiFePO_(4)动力电池多加速参数耦合的加速循环寿命高效评估研究提供参考,同时也可为动力电池延长使用寿命的设计提供参考。

LiFePO_4动力电池直流等效内阻劣化规律研究

对Li Fe PO4动力电池进行循环测试,循环条件包括不同的环境温度,不同充放电倍率,不同的充放电区间和充放电深度等。通过总结直流等效内阻的劣化规律,选择荷电状态(SOC)为0.5～0.8区间的直流等效内阻总和作为内阻谱的表征参数,对比不同电池样本的直流等效内阻变化规律,结果表明工作环境温度是决定电池内阻增长速度的主要因素。

Life Prediction Based on Transient Dynamics Analysis of Van Semi-trailer with Air Suspension System

The early fatigue damage in the van-body of the semi-trailer is often caused by the unique mechanical characteristics and the dynamic impact of the loads.The traditional finite element method with static strength analysis cannot support the fatigue design of van-body;thus,the dynamics analysis should be adopted for the endurance performance.The accurate dynamics model to describe the transient impacts of all kinds of uneven road and the proper system transfer functions to calculate the load transfer effects from tire to van-body are two critical factors for transient dynamics analysis.In order to evaluate the dynamic performance,the dynamics model of the trailer with the air suspension is brought forward.Then the analysis method of the power spectral density （PSD） is set up to study the transient responses of the road dynamic impacts.The transient responses transferred from axles to van-body are calculated,such as dynamic stress,dynamic RMS acceleration,and dynamic load factors.Based on the above dynamic responses,the fatigue life of van-body is predicted with the finite element analysis （FEA） method.Applying the test parameters of the trailer with air suspension,the simulation system with Matlab/Simulink is constructed to describe the dynamic responses of the impacts of the tested PSD of the vehicle axles,and then the fatigue life is predicted with FEA method.The simulated results show that the vibration level of the van-body with air suspension is reduced and the fatigue life is improved.The real vehicle tests on different roads are carried out,and the test results validate the accuracy of the simulation system.The proposed fatigue life prediction method is effective for the virtual design of auto-body.

PowerDesigner工具集及其应用

简要地介绍了一种计算机辅助软件工程（CASE）工具集中的PowerDesigner,讨论了其在电力企业管理信息系统（MIS）开发中的应用．指出了在MIS开发中体现分析设计过程和结果的文档是非常重要的，文档产生的速度快慢、文档的质量高低是决定MIS开发项目能否取得成功、MIS是否具有生命力的重要因素之一，而CASEI具集能帮助我们快速清晰地表达、分析设计思想，是我们开发MIS形成清晰文档的有力工具．

新能源汽车动力电池回收利用过程减碳成效测算

为量化评价新能源汽车动力电池回收利用过程的环境效益,为报废动力电池管理体系和回收再利用相关标准的完善提供支撑,助力国家“双碳”目标的实现,以三元锂电池为研究对象,选取典型的动力电池回收利用场景,将三元锂电池的生命周期划分为4个阶段:原材料获取、制造装配、使用和报废回收,并建立相应的GaBi模型,基于湿法回收A、湿法回收B、火法-湿法联合回收3种不同回收利用方式进行三元锂电池生命周期评价模型搭建与回收再利用过程减碳成效测算。研究结果表明,三元锂电池回收再利用过程有较好的减碳成效,基于3种不同回收工艺的三元锂电池回收再利用可以减少CO_(2)排放量分别为:湿法回收A为60.71kgCO_(2)/kWh;湿法回收B为150.00kgCO_(2)/kWh;火法-湿法联合回收为153.57 kg CO_(2)/kWh。基于这3种不同回收工艺的CO_(2)减排效果从优至劣依次为:湿法-火法联合回收、湿法回收B和湿法回收A。合理的动力电池回收利用方式可以显著减少其回收利用过程中的碳排放量,从而产生更好的环境效益。

Study on Prediction Method of Structural Three-parameter Power Function P-S-N Curve

This paper applies weighted least square method to estimate the three-parameter power function equation of the fatigue life curve, and uses comprehensive fatigue life coefficient to correct the equation, and at the same time combines probability statistics method to bring out the prediction method of structure＇s three- parameter power function P-S-N curve, finally applies the prediction method to a ship＇s frame-type elevate, based on the fatigue test data of it＇s material-SA06 aluminium alloy, to obtain it＇s structure＇s three-parameter power function P-S-N curve. Compared with the conventional least square method, the presented method can give

Aging and Life Management System of Reactor Pressure Vessel

Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life of RPV, and thus, the aging and life research on a RPV is a key factor in determining the life extension of NPPs. The purpose of this paper is to introduce an aging and life management system for an operating RPV which can be used as a reference of the lifetime extension. In order to realize the objective, an aging and life management system was developed. It is an comprehensive knowledge management system that integrates decentralized information and serves as a valuable data center. Based on the storage and management of RPV state information and operation data, this system provides real-time monitoring of important operating parameters, evaluation of irradiation embrittlement, and RPV aging assessment. Therefore, it is anticipated that the developed system can be used as an efficient tool for aging and life estimation of RPV.

基于全生命周期评价的冷热电联供系统优化研究

天然气与太阳能互补是提高能源利用率和实现节能减排的有效方法,该文构建一种光-气-储互补的冷热电联供(CCHP)系统。基于全生命周期理论,以一次能源节约率、总污染物减排率为目标函数,建立冷热电联供系统优化模型,应用遗传算法对系统变工况运行下的容量配置进行优化;将物质回收阶段纳入全生命周期评价,并在运输阶段考虑燃料运输。结果表明:经优化后,CCHP系统电跟随(FEL)策略可实现较好的节能减排效益。分供(SP)系统在物质回收阶段对环境的影响微乎其微,CCHP系统燃料运输能耗量远低于SP系统。

基于政策文本分析的我国科研诚信建设职责划分研究

科研诚信是科技创新的基石,而科研诚信政策则是健全完善科研诚信工作机制强大的制度保障,文章从科研诚信政策深入探究我国科研诚信建设的责任主体及职责分布,采用科研生命周期理论,通过系统地文献检索、文献筛选,对69份政策文件进行主题分析。结果表明:各级政府和相关行业主管部门是科研诚信建设的领导者,各类科研和管理机构是科研诚信建设的管理者,各类科研和管理人员是科研诚信建设的践行者,各个责任主体在科研生命周期的不同阶段具有不同的职责,分布亦有所侧重。研究有助于明晰我国科研诚信建设的责任主体和职责分布,对进一步推进科研诚信政策建设和深入理解我国科研诚信制度建设的实际具有参考作用。

基于改进VIKOR算法的梯次利用电池电网储能场景适用性评价方法

快速发展的电动汽车带来了巨量的退役动力电池,但其梯次利用场景缺乏科学的甄选方法。研究了梯次利用电池电网储能场景适用性评价方法。首先,从技术性能、经济性能和安全性能3个维度,构建了综合考虑电池运行状态、储能配置经济效益和梯次利用安全风险的梯次利用电池电网储能场景适用性评价指标体系。其次,采用多属性群决策方法优化设定评价维度权重,采用CRITIC法和熵权法形成组合赋权法对评价指标进行权重设置,设计了基于改进VIKOR算法的应用场景适用性评价算法。最后,针对峰谷套利、平抑可再生能源出力波动和调频辅助服务3种典型电网储能应用场景,量化计算了给定退役动力电池状态下电网储能应用场景的适用度。提出的梯次利用电池电网储能场景适用性评价方法可为给定状态的退役动力电池甄选出适用场景,为实际工程相关决策人员提供决策依据。

基于电池寿命控制策略的交流充电桩设计

针对充电电流对动力电池寿命和性能的影响,提出一种基于电池寿命控制策略的交流充电方式。考虑整个充电系统存在较强的非线性与延迟,采用模糊神经网络控制算法,以马斯最佳充电电流曲线为充电过程中充电电流的实时控制目标,对充电过程中整个充电电流进行实时监测并控制。此外,推导模糊神经网络算法的3个控制参数△k_(p)、△k_(i)、△k_(d),完成实时控制充电电流I_(c)的理论推导,并设计整个控制策略的软件程序框架,搭建整个充电桩的架构,可为家用新能源汽车的充电桩设计提供新的思路和参考。

退役动力电池加速寿命实验教学试验方法设计

为了准确估计退役动力电池的寿命,合理将其进行梯次利用是目前研究的重点,也是高校实验教学开展的重要内容。因此,通过一种基于逆幂律模型的加速寿命试验方法对退役动力电池进行研究。此试验方法涉及了仪器设备和仿真软件等多个理论基础知识,系统地训练了学生资料查询、试验操作与分析的能力。在试验中,首先在不同倍率下对退役动力电池进行充放电实验,建立放电倍率与健康度的关联特性;其次,搭建动力电池的加速寿命试验平台,选取不同放电倍率为加速应力进行加速寿命试验;最后,通过仿真与试验结果进行分析,进一步确定动力电池的寿命衰减特性,为高校教学研究动力电池的梯次利用提供参考。此外,通过仿真试验和教学平台的有机结合,提高学生实际工程应用和开发的实践综合能力。

航天地面电源加速寿命试验研究

以某航天地面电源为研究对象,开展加速寿命试验研究。首先,介绍了加速寿命试验的特点、目的和优点;然后,阐述了加速试验的方法和流程;最后,对加速寿命试验的结果进行了分析。结果表明,与传统的可靠性试验相比,加速寿命试验可有效降低试验成本、提升试验效率,具有绝对优势。

计及电池寿命的储能系统参与二次调频功率分配策略

储能系统辅助火电机组二次调频具有响应速度快、跟踪精度高等优点,但功率分配不当会加速电池寿命衰减,导致运行成本增加,经济效益下降。如何制定合理的储能功率分配策略,在确保调频性能的同时延长电池寿命并提高经济效益,已成为亟待解决的重要问题。首先基于二阶RC等效电路建立储能锂电池的数学模型,采用限定记忆最小二乘递推算法辨识模型参数;随后,在火储联合调频模型的基础上,对基于比例、差额和频率的3种功率分配策略进行了仿真分析;最后,根据江苏某660 MW火电机组的实际运行数据,重点分析了不同策略对系统调频性能、电池寿命及经济性的影响。结果表明,比例分配策略的调频效果最差,且会加速电池寿命衰减;差额分配策略在调频性能上表现优异,但对电池寿命的改善有限;频率分配策略能够有效降低电池更换频率,可提高整体经济效益。总体而言,频率分配策略不仅可提高系统的调频能力,还能最大限度延长电池寿命并优化经济效益,在储能系统辅助火电机组二次调频中具有显著的应用优势。

一种可解释人工智能(XAI)在测量设备故障诊断和寿命预测中的应用

基于人工智能算法的变压器故障诊断和寿命预测模型在提高准确率方面已经达到了很好的效果,但是仍存在泛化性能较低,对数据质量要求过高,判断结果无法解释等问题.该文基于DBSO-CatBoost模型,提出一种可用于故障判断解释的变压器故障诊断方法.该方法基于数据特征提取,采用差分变异头脑风暴优化(DBSD)算法对CatBoost模型进行优化和故障诊断.①对于数据预处理,引入比率法在原始数据中添加特征;采用基于可解释人工智能(XAI)的Shapley加法解释(SHAP)技术进行特征提取,并采用核主成分分析算法对数据进行降维.Shapley加法解释技术可根据特征贡献解码每个预测来帮助全局解释并评估预测结果.②将预处理后的数据输入到CatBoost模型中进行训练,并采用差分变异头脑风暴优化算法对CatBoost模型的参数进行优化,从而得到最优模型.③利用得到的优化模型诊断变压器故障并输出故障类型与预测结果.实验使用来自中国国家电网公司西北部某电网的真实数据评估该模型.结果表明:该文模型在不同故障诊断中的准确性最佳,平均准确率高达99.29%,证明该文方法可以有效提高电力变压器故障诊断的准确性和效率.

基于非纤维方向应力疲劳模型的复合材料层合板振动寿命预测

复合材料结构在服役过程中会受到外部载荷激励影响而产生随机振动,由于铺层角度的多样性使其寿命预测方法尚不明确。为确保复合材料结构安全服役,需探明复合材料不同铺层角度的振动疲劳寿命预测方法。本文提出一种基于非纤维方向S-N曲线的预测方式,考虑了复合材料的各向异性和多轴应力状态,以Tsai-Wu准则为基础,结合频域法对[0/90]s铺层的复合材料层合板进行了振动疲劳寿命预测。结果表明,非纤维方向S-N曲线能够较为准确地预测复合材料层合板的寿命,且Zhao-Baker概率密度函数模型的准确性最高。