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Adaptive Optimal Tracking Control for Continuous-Time Systems Using Identifier-Critic Based Dynamic Programming

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Adaptive Optimal Tracking Control for Continuous-Time System...

Characteristics of emissive spectrum and the removal of nitric oxide in N_2/O_2/NO plasma with argon additive

第36届中国控制会议

作者： dawei hou Jing Na Yongfeng Lv Guanbin Gao Xing Wu Kunming University Of Science & Technology Faculty Of Mechanical & Electrical Engineering School of Automation Beijing Institute of Technology

ISBN: (纸本)9781538629185

This paper proposes an optimal tracking control of completely unknown affine nonlinear systems using a system augmentation scheme and a modified discounted performance function, where the feedforward and feedback control actions can be obtained simultaneously. We first present an adaptive identifier to estimate the unknown dynamics, where the estimated parameters are updated based on a new adaptive law such that these estimated parameters converge to a small neighborhood around their true values. An augmented system consisting of the tracking error and the generator of the trajectory to be tracked are then constructed, which derives an augmented tracking Hamilton-Jacobi-Bellman（HJB） equation. An online critic neural network（NN） is finally presented to approximate the optimal value function of HJB equation, and then calculate the optimal control action. This leads to an identifier-critic based adaptive dynamic programming（ADP） structure. Simulation results are presented to demonstrate the effectiveness of the proposed method.

关键词： Optimal Tracking Control Adaptive Control Adaptive Dynamic Programming System Augmentation

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Journal of Environmental Sciences 2009年第6期21卷 790-794页

作者： LIN Wenfeng,ZHANG Bin,hou Wenhui,LI dawei,YANG Hongmin School of Power Engineering,Nanjing Normal University,Nanjing 210042,China School of Power Engineering Nanjing Normal University Nanjing 210042 China. E-mail: booboo.ai@***

Although the approach using non-thermal plasma（NTP） for deNOx has been studied for over 15 years,how to achieve higher removal effciency with lower cost is still a barrier for its industrial *** order to investigate the impact of the argon additive on electron density,energy and nitric oxide reduction process in plasma,the spectrum of the dielectric barrier discharge at atmospheric pressure in a coaxial reactor was measured using the monochromater with high *** comparative experiments for NO reduction were carried out simultaneously in N2/O2/NO plasma stream with and without argon,*** nitrogen molecular spectrum which is attributed to the energy level transition（C^3πu→ B^3πg） was compared in the wavelength range 300-480 nm and the electron density and temperature were determined based on the relative intensities and Stark broadening width of spectral *** spectrum results indicated that the argon additive could enhance the intensity of emissive spectrum of plasma,thus the electron concentration as well as the energy was increased,and finally prompted the ionization rate to produce active N,O and *** results of NO reduction showed that NO conversion effciency increased in the range of 10%-30% with 5% addition of argon in stream comparing with the condition without argon *** study will play a positive role in the industrial application of dielectric barrier discharge deNOx reactor.

关键词： argon emissive spectrum nitric oxide non-thermal plasma

退耕还林背景下寒地山区土地生态安全格局动态变化

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农业工程学报 2017年第18期33卷 267-276页

作者：侯大伟刘艳孙华南京农业大学土地管理学院南京210095

为了研究退耕还林工程引起的土地生态安全格局变化,该文应用遥感和GIS技术对牡丹江地区2000-2014年土地利用变化特征进行了分析,并基于DPSIR概念框架构建评价指标体系,从空间上揭示了研究区退耕还林期间土地生态安全水平及格局变化。结... 详细信息

为了研究退耕还林工程引起的土地生态安全格局变化,该文应用遥感和GIS技术对牡丹江地区2000-2014年土地利用变化特征进行了分析,并基于DPSIR概念框架构建评价指标体系,从空间上揭示了研究区退耕还林期间土地生态安全水平及格局变化。结果表明,退耕还林工程的实施对研究区土地利用结构产生了极大的影响,林地面积增加1 520.16 km^2,草地、耕地面积分别减少878.50、517.14 km^2,土地利用强度先下降后上升;退耕还林工程在有效控制坡地垦殖、增加林地面积的同时,能够显著提高区域土地生态安全水平,2000-2014年,各坡度等级内安全、较安全、临界安全面积共增加1 088.6 km^2;14 a来研究区土地生态安全水平总体呈"先改善后恶化"的趋势,但仍较2000年工程实施前有了较大幅度的提升,西部、东部及南部地区土地生态安全水平显著提高,但中部牡丹江河谷盆地土地生态安全水平提升缓慢,建议新一轮退耕还林工程将此地区作为重点调控整治区域。

关键词：土地利用生态植被退耕还林土地生态安全寒地山区

Decade Milestone Advancement of Defect-Engineered g-C_(3)N_(4) for Solar Catalytic Applications

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Nano-Micro Letters 2024年第4期16卷 153-218页

作者： Shaoqi hou Xiaochun Gao Xingyue Lv Yilin Zhao Xitao Yin Ying Liu Juan Fang Xingxing Yu Xiaoguang Ma Tianyi Ma dawei Su School of Mathematical and Physical Sciences Faculty of ScienceUniversity of Technology Sydney(UTS)SydneyNSW 2007Australia Laboratory of Plasma and Energy Conversion School of Physics and Optoelectronic EngineeringLudong University186 Middle Hongqi RoadYantai 264025People’s Republic of China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083People’s Republic of China Department of Chemistry The University of Tokyo7‑3‑1 HogoBunkyoTokyoJapan School of Science STEM CollegeRMIT UniversityMelbourneVIC 3000Australia

Over the past decade, graphitic carbon nitride(g-C_(3)N_(4)) has emerged as a universal photocatalyst toward various sustainable carbo-neutral technologies. Despite solar applications discrepancy, g-C_(3)N_(4) is still confronted with a general fatal issue of insufficient supply of thermodynamically active photocarriers due to its inferior solar harvesting ability and sluggish charge transfer dynamics. Fortunately, this could be significantly alleviated by the “all-in-one” defect engineering strategy, which enables a simultaneous amelioration of both textural uniqueness and intrinsic electronic band structures. To this end, we have summarized an unprecedently comprehensive discussion on defect controls including the vacancy/non-metallic dopant creation with optimized electronic band structure and electronic density, metallic doping with ultraactive coordinated environment(M–N_(x), M–C_(2)N_(2), M–O bonding), functional group grafting with optimized band structure, and promoted crystallinity with extended conjugation π system with weakened interlayered van der Waals interaction. Among them, the defect states induced by various defect types such as N vacancy, P/S/halogen dopants, and cyano group in boosting solar harvesting and accelerating photocarrier transfer have also been emphasized. More importantly, the shallow defect traps identified by femtosecond transient absorption spectra(fs-TAS) have also been highlighted. It is believed that this review would pave the way for future readers with a unique insight into a more precise defective g-C_(3)N_(4) “customization”, motivating more profound thinking and flourishing research outputs on g-C_(3)N_(4)-based photocatalysis.

关键词： Defect engineering g-C_(3)N_(4) Electronic band structures Photocarrier transfer kinetics Defect states

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燃煤电站SO3迁移转化特性试验分析

热力发电 2020年第4期49卷 29-33页

作者：侯大伟中国大唐集团科学技术研究院有限公司华东电力试验研究院安徽合肥230000

燃煤烟气中SO3质量浓度较低,性质活泼易被吸附,同时SO3捕集效率偏低,因此难以获得燃煤电厂SO3酸雾典型排放数据。本文在分析介绍主流SO3酸雾监测方法的基础上,选用异丙醇吸收法对典型燃煤电站烟气处理设备协同脱除SO3作用展开试验研究... 详细信息

燃煤烟气中SO3质量浓度较低,性质活泼易被吸附,同时SO3捕集效率偏低,因此难以获得燃煤电厂SO3酸雾典型排放数据。本文在分析介绍主流SO3酸雾监测方法的基础上,选用异丙醇吸收法对典型燃煤电站烟气处理设备协同脱除SO3作用展开试验研究。结果表明:燃煤产生的SO3质量浓度因不同的燃烧方式有较大差异,其与入炉煤质的含硫量正相关,SCR脱硝过程中SO2/SO3的转化率为0.44%~1.02%;电除尘器对于SO3的脱除效率约40%,除尘器进口SO3的质量浓度较高时,其脱除效率可略微提升,而电袋复合除尘器对于SO3的协同脱除效果更佳;湿式电除尘系统在不同工况下,对于SO3的脱除效率介于44%~75%之间,SO3排放质量浓度可控制在5 mg/m3以下;常规湿法脱硫系统SO3脱除效率在38%~56%之间,托盘塔对SO3酸雾的协同脱除效果更好。

关键词：燃煤电站 SO3 酸雾监测方法迁移转化异丙醇吸收法协同脱除

An Ultra-wideband Doubler Chain with 43–65 dBc Fundamental Rejection in Ku/K/Ka Band

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Chinese Journal of Electronics 2024年第5期33卷 1204-1217页

作者： Long WANG Jixin CHEN Debin hou Xiaojie XU Zekun LI dawei TANG Rui Zhou Hao QI Yu XIANG State Key Laboratory of Millimeter Waves Southeast University MISIC Microelectronics Co.Ltd.

In this paper, a double-balanced doubler chain with >43-dBc fundamental rejection over an ultra-wide bandwidth in 0.13-μm SiGe BiCMOS technology is proposed. To achieve high fundamental rejection, high output power, and high conversion gain over an ultra-wideband, a double-balanced doubler chain with pre-and post-drivers employs a bandwidth broadening technique and a ground shielding strategy. Analysis and comparison of the singlebalanced and double-balanced doublers were conducted, with a focus on their fundamental rejection and circuit imbalance. Three doublers, including a passive single-balanced doubler, an active single-balanced doubler, and a passive double-balanced doubler were designed to verify the performance and characteristics of the single-and doublebalanced doublers. Measurements show that the proposed double-balanced doubler chain has approximately 15 dB better fundamental rejection, and more than twice the relative bandwidth compared to the single-balanced doubler chain fabricated with the same process. Over an 86.9% 3-dB bandwidth from 13.4 GHz to 34 GHz, the double-balanced doubler chain delivers 14.7-dBm peak output power and has >43-/33-dBc fundamental/third-harmonic rejection. To the authors' best knowledge, the proposed double-balanced doubler chain shows the highest fundamental rejection over an ultra-wideband among silicon-based doublers at millimeter-wave frequency bands.

关键词： Millimeter wave technology Bandwidth Harmonic analysis Frequency conversion Millimeter wave communication Power generation Gain Doubler Double-balanced Fundamental rejection Single-balanced FREQUENCY DOUBLER POWER-AMPLIFIER GAIN COMPENSATION EFFICIENCY SILICON

Quantitative Detection and Attribution of Runoff Variations in the Aksu River Basin

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Quantitative Detection and Attribution of Runoff Variations ...

一种基于实例分割和点云配准的六维位姿估计方法

第十五届中国水论坛

作者：孟凡浩刘铁 HUANG Yue LUO Min BAO Anming hou dawei State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences University of Chinese Academy of Sciences The College of Public Administration Nanjing Agricultural University

Since the flow variations of Aksu River are strongly influenced by climate change and human activities which threat the local ecosystem and its sustainable development, it is necessary to quantify the impact degree of driven factors. Therefore, this study aims to quantify the impacts of climate change and human activities on the variability of runoff in the Aksu River Basin. The Mann-Kendall trend test and accumulative anomaly method were used to analyse the break points of the flow difference value（FDV） between the upstream and downstream flume stations. The improved slope change ratio of cumulative quantity（SCRCQ） method and the Soil and Water Assessment Tool（SWAT） model were applied to decouple the contribution of each driving factor to the FDV variations. Furthermore, a Pearson correlation analysis was performed to show the relationships among the driving factors and the FDV. The time series prior to the year（1988） of break point was considered the baseline period. Based on the mean annual precipitation and the potential evapotranspiration（PET）, the relative impacts of precipitation, PET and human activities on FDV variations as determined by the SCRCQ method were 77.35%,-0.98% and 23.63%, respectively. In addition, the SWAT model indicated that climate factors and human activities were responsible for 92.28% and 7.72% of the variability, respectively. Thus, climate change and human activities showed a similar scale of impact on FDV changes.

关键词： runoff variation climate change human activities Aksu River

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信息技术与网络安全 2021年第6期40卷 56-61页

作者：侯大伟中国科学技术大学信息科学技术学院安徽合肥230026

本文提出一种基于Mask R-CNN实例分割网络和Super4PCS点云配准算法来估计物体六维姿态的方法。通过目标点云与已知位姿的参考点云进行配准,可以获取目标的六维姿态。但实际中往往采用三维设备扫描目标的整体环境,生成的点云数量庞大,直... 详细信息

本文提出一种基于Mask R-CNN实例分割网络和Super4PCS点云配准算法来估计物体六维姿态的方法。通过目标点云与已知位姿的参考点云进行配准,可以获取目标的六维姿态。但实际中往往采用三维设备扫描目标的整体环境,生成的点云数量庞大,直接作为源点云与参考点云配准时,会由于候选集较多从而导致运算时间太长,因此本文先对目标实例分割处理后再配准:首先,利用深度相机获取整体环境的RGB-D图,其次利用Mask R-CNN模型将把目标分割出来,并将分割的目标RGB-D图转化为点云图,利用Super4PCS点云配准算法与参考点云进行配准,最终得到目标的六维位姿。在自制作的数据集上进行了验证,对比分割前后的四组实验,时间降低率约为60%-80%,有效证明了本方法的可行性。

关键词：六维姿态估计 Mask R-CNN实例分割 Super4PCS点云配准

典型棕地修复前后土壤重金属生态风险变化——以江西贵溪冶炼厂为例

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生态学报 2017年第18期37卷 6128-6137页

作者：张金婷孙华谢丽侯大伟南京农业大学资源环境与城乡规划系南京210095

目前,我国对于棕(褐)地周边区域生态风险的研究较少,且主要是针对风险源带来的潜在危害进行评价,没有考虑风险受体能够承受生态风险能力的大小,生态风险评价研究不全面。在棕(褐)地周边区域的生态风险评价中加入风险受体的相关研究,主... 详细信息

目前,我国对于棕(褐)地周边区域生态风险的研究较少,且主要是针对风险源带来的潜在危害进行评价,没有考虑风险受体能够承受生态风险能力的大小,生态风险评价研究不全面。在棕(褐)地周边区域的生态风险评价中加入风险受体的相关研究,主要从风险源的危害分析和风险受体的生态脆弱性两方面对生态风险进行评价,使评价更加全面,另外,现有研究少有对生态风险在时间上的变化研究,考虑了生态风险时间上的变化,对贵溪冶炼厂周边两个时期的生态风险进行评价并分析其变化,利用GIS软件对评价结果进行空间表达,对研究区域存在的生态风险空间差异进行分析。结果表明:修复前苏门区、九牛岗、水泉区、串山垅等地区存在很强生态风险,沈家-林家区和长塘周家区的生态风险相对较小,处于中等风险水平,修复后研究区的生态风险大大降低,很强风险降为强风险水平,中等风险降为低风险,说明修复方式比较有效,但仍有小范围区域存在较强风险,应加强修复,研究区域中耕地的生态脆弱性最大。对于生态脆弱性较大且生态风险较大的区域应进一步进行修复治理,生态脆弱性大而生态风险较低的地区应加强监测防范,防止再次发生较强风险。

关键词：棕(褐)地生态风险重金属