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基于扩张状态观测器的双母管系统预测控制

控制工程 2024年第3期31卷 489-496页

作者：唐炜洁沈炯张俊礼王海涛董宸中国能源建设集团江苏省电力设计院有限公司江苏南京211102 东南大学能源与环境学院江苏南京211189

双母管式机组较为广泛地应用于热电联产机组中,但由于多炉多机和2根大容量母管互相影响,导致热电负荷跟踪不及时,母管压力控制自动化水平较低。为此,针对双母管系统的非线性、强耦合、大迟延特性,设计了基于广义扩张状态观测器的多模型... 详细信息

双母管式机组较为广泛地应用于热电联产机组中,但由于多炉多机和2根大容量母管互相影响,导致热电负荷跟踪不及时,母管压力控制自动化水平较低。为此,针对双母管系统的非线性、强耦合、大迟延特性,设计了基于广义扩张状态观测器的多模型预测控制(generalized extended state observer based muti-model predictive control,GESOMMPC)方法。首先,建立了基于间隙度量(gap-metric)的多模型控制对象用于逼近非线性系统;其次,设计了扩张状态观测器估计系统耦合的集总扰动,并作为前馈信号输入到预测控制器中;最后,设计基于扰动前馈的多模型预测控制器实现对双母管系统的控制。实验结果表明,相对于PID方法,所提方法在满足电热负荷的同时,可以在允许范围内保持母管压力稳定,且动态偏差更小,过渡过程时间更短。

关键词：双母管状态观测器预测控制间隙度量多模型

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校企协同育人促单片机课程实践教学改革与实践

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创新创业理论研究与实践 2024年第9期7卷 46-48+56页

作者：唐伟杰曹少泳北京理工大学珠海学院工业自动化学院

单片机课程是工科类专业非常重要的核心课程，对学科竞赛、学生科研项目以及学生就业有巨大的推动作用。该课程非常注重实践环节，而传统的实践课程教学与产业需求脱节，学生被动地接受知识，学习积极性不高，教学效果不佳。该文探讨基... 详细信息

单片机课程是工科类专业非常重要的核心课程，对学科竞赛、学生科研项目以及学生就业有巨大的推动作用。该课程非常注重实践环节，而传统的实践课程教学与产业需求脱节，学生被动地接受知识，学习积极性不高，教学效果不佳。该文探讨基于校企协同育人促进单片机课程实践教学质量的提升，在实践教学中，高校与企业紧密合作，以专业认证为指导，共同开发设计实践教学内容，融合项目驱动式教学，校企协同以赛促学，取得了良好的成效。

关键词：校企协同育人单片机课程实践教学专业认证项目驱动以赛促学

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煤制气遗留场地修复后再开发安全利用评估

环境监控与预警 2024年第3期16卷 65-71页

作者：刘翠翠唐卫杰王栋王水江苏省环境科学研究院江苏南京210036 江苏省环境工程重点实验室江苏南京210036 中国科学院南京土壤研究所江苏南京210008 江苏省环境工程技术有限公司江苏南京210019 江苏省环保集团有限公司江苏南京210036

随着社会经济发展和城镇建设加快,原有土地使用性质发生改变,其中工业遗留场地的污染物可能对土壤和地下水造成污染。但由于修复技术的局限性以及水文地质的复杂性,修复后场地仍然可能存在不利于安全利用的物质残留或异味等风险隐患。... 详细信息

随着社会经济发展和城镇建设加快,原有土地使用性质发生改变,其中工业遗留场地的污染物可能对土壤和地下水造成污染。但由于修复技术的局限性以及水文地质的复杂性,修复后场地仍然可能存在不利于安全利用的物质残留或异味等风险隐患。为了进一步完善污染地块修复后再利用评价方法,对可能存在的污染风险进行识别,现选取了一块经原位化学氧化和原位热脱附修复后的煤制气遗留场地,从感官可接受度、工程安全性和环境质量3个方面系统全面地评估场地修复后再开发安全利用的适宜性。评估结果表明,在感官可接受度方面,硫化氢的质量浓度是其嗅阈值的1.6~4.8倍,氨、甲苯和三氯甲烷质量浓度均低于其嗅阈值,臭气浓度低于检出限,感官可接受程度高;在工程安全性方面,地块经原位热脱附和原位化学氧化修复后,基本土性参数、压缩系数和渗透系数未发生明显改变,但是原位化学氧化区MH2点位浅层土壤硫酸盐残留浓度达到中腐蚀等级;在环境质量方面,修复后场地土壤中和地下水中污染物的质量浓度均低于相应评价标准限值。在场地后期开发建设中,应进一步对土壤中硫化氢气体和土壤硫酸盐腐蚀性进行监测,确保地块安全开发利用。研究结果可为其他污染地块修复后的再利用提供有效、科学的指导。

关键词：煤制气遗留场地原位化学氧化原位热脱附安全利用评估

基于轻量级MobileNetV2-DeeplabV3+的棒材分割方法

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重庆工商大学学报（自然科学版） 2024年第3期41卷 66-71页

作者：汤维杰方挺韩家明袁东祥安徽工业大学电气与信息工程学院安徽马鞍山243000

针对当前语义分割模型为提升像素分割精度,不断增加算法复杂度,导致模型出现参数量大,耗时长,难以部署至工业现场等问题,提出一种基于轻量级MobileNetV2-DeeplabV3+模型的棒材分割算法。算法为平衡像素分割精度、模型参数量和算法检测速... 详细信息

针对当前语义分割模型为提升像素分割精度,不断增加算法复杂度,导致模型出现参数量大,耗时长,难以部署至工业现场等问题,提出一种基于轻量级MobileNetV2-DeeplabV3+模型的棒材分割算法。算法为平衡像素分割精度、模型参数量和算法检测速度,在原网络基础上做出一系列改进:将原有的Xception主干网络替换为轻量级MobileNetV2网络以降低模型参数量与计算复杂度;在空洞空间金字塔池化(ASPP)模块基础上密集连接各空洞卷积以获得更大的感受野,更加密集的像素采样,并扩大输出特征覆盖的语义信息;使用深度可分离卷积(DSConv)替代ASPP模块中的标准卷积进一步降低模型的计算复杂度;此外,引入有效通道注意力(ECA)模块聚焦目标边缘特征,增强特征图通道信息提取的效果。实验表明:改进后的模型在棒材数据集下平均交并比(MIOU)为89.37%,平均像素精度(MPA)为94.57%,帧率(FPS)为33.09帧/s,模型参数量为33.6 M。与U-net、M-PSPNet、M-DeeplabV3+等模型相比,改进后算法的MIOU值与MPA值略低于最佳值,但仍处于较高水准,模型参数量小,FPS值得到较大提升。实验表明:改进后的算法能较好地平衡分割精度和算法实时性,能满足部署至工业现场的需求。

关键词：语义分割 DeepLabv3+模型轻量级棒材

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Estimation of spectral responses and chlorophyll based on growth stage effects explored by machine learning methods

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The Crop Journal 2022年第5期10卷 1292-1302页

作者： Dehua Gao Lang Qiao Lulu An Ruomei Zhao Hong Sun Minzan Li weijie tang Nan Wang Key Laboratory of Modern Precision Agriculture System Integration Research Ministry of EducationChina Agricultural UniversityBeijing 100083China Key Laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing 100083China Yantai Institute of China Agricultural University Yantai 264670ShandongChina

Estimation of leaf chlorophyll content(LCC) by proximal sensing is an important tool for photosynthesis evaluation in high-throughput phenotyping. The temporal variability of crop biochemical properties and canopy structure across different growth stages has great impacts on wheat LCC estimation, known as growth stage effects. It will result in the heterogeneity of crop canopy at different growth stages, which would mask subtle spectral response of biochemistry variations. This study aims to explore spectral responses on the growth stage effects and establish LCC models suited for different growth stages. A total number of 864 pairwise samples of wheat canopy spectra and LCC values with 216 observations of each stage were sampled at the tillering, jointing, booting and heading stages in 2021. Firstly, statistical analysis of LCC and spectral response presented different distribution traits and typical spectral variations peak at 470, 520 and 680 nm. Correlation analysis between LCC and reflectance showed typical red edge shifts. Secondly, the testing model of partial least square(PLS) established by the entire datasets to validate the predictive performance at each stage yielded poor LCC estimation accuracy. The spectral wavelengths of red edge(RE) and blue edge(BE) shifts and the poor estimation capability motivated us to further explore the growth stage effects by establishing LCC models at respective growth ***, competitive adaptive reweighted sampling PLS(CARS-PLS), decision tree(DT) and random forest(RF) were used to select sensitive bands and establish LCC models at specific stages. Bayes optimisation was used to tune the hyperparameters of DT and RF regression. The modelling results indicated that CARS-PLS and DT did not extract specific wavelengths that could decrease the influences of growth stage effects. From the RF out-of-bag(OOB) evaluation, the sensitive wavelengths displayed consistent spectral shifts from BE to GP and from RE to RV from t

关键词： Wheat chlorophyll content Growth stage effects Sensitive wavelengths Spectral response Random forest

不同浓度茉莉酸甲酯处理对“金冠”苹果保鲜效果的影响

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包装与食品机械 2024年第1期42卷 12-18页

作者：唐伟杰张潆支张良吕静祎孙明宇葛永红陈敬鑫渤海大学食品科学与工程学院辽宁锦州121013 锦州市检验检测认证中心辽宁锦州121013

以“金冠”苹果果实为试验对象,研究10,100,1500µmol/L的茉莉酸甲酯处理对其在常温(20±2)℃贮藏期间保鲜效果的影响。结果表明:在第21 d,1500µmol/L MeJA处理组的呼吸速率和乙烯释放速率高峰分别是对照组的1.07,1.05倍,而10µmol/L M... 详细信息

以“金冠”苹果果实为试验对象,研究10,100,1500µmol/L的茉莉酸甲酯处理对其在常温(20±2)℃贮藏期间保鲜效果的影响。结果表明:在第21 d,1500µmol/L MeJA处理组的呼吸速率和乙烯释放速率高峰分别是对照组的1.07,1.05倍,而10µmol/L MeJA处理组分别比对照组低26%和24%。在第35 d,1500µmol/L MeJA处理组的硬度、可滴定酸和总酚含量分别比对照组低5%,10%和9%,而10µmol/L MeJA处理组分别是100µmol/L MeJA处理组的1.05,1.07,1.04倍。在第35 d,10µmol/L MeJA处理组的丙二醛含量及O2-·产生速率比对照组分别低14%和12%,都比100µmol/L MeJA处理组低5%,而1500µmol/L MeJA处理组分别是对照组的1.06,1.16倍。10µmol/L MeJA处理的保鲜效果更佳,1500µmol/L MeJA处理则有相反效果,加速果实的成熟与衰老。研究为苹果保鲜新技术的开发提供参考。

关键词：苹果茉莉酸甲酯保鲜品质

Federated Learning Model for Auto Insurance Rate Setting Based on Tweedie Distribution

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工程与科学中的计算机建模(英文) 2024年第1期138卷 827-843页

作者： Tao Yin Changgen Peng weijie Tan Dequan Xu Hanlin tang State Key Laboratory of Public Big Data Guizhou UniversityGuiyang550025China Guizhou Big Data Academy Guizhou UniversityGuiyang550025China Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang550025China College of Computer Science and Technology Guizhou UniversityGuiyang550025China ChinaDataPay Company Guiyang550025China

In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie *** traditional approach to obtaining the Tweedie regression model involves training on a centralized dataset,when the data is provided by multiple parties,training a privacy-preserving Tweedie regression model without exchanging raw data becomes a *** address this issue,this study introduces a novel vertical federated learning-based Tweedie regression algorithm for multi-party auto insurance rate setting in data *** algorithm can keep sensitive data locally and uses privacy-preserving techniques to achieve intersection operations between the two parties holding the *** determining which entities are shared,the participants train the model locally using the shared entity data to obtain the local generalized linear model intermediate *** homomorphic encryption algorithms are introduced to interact with and update the model intermediate parameters to collaboratively complete the joint training of the car insurance rate-setting *** tests on two publicly available datasets show that the proposed federated Tweedie regression algorithm can effectively generate Tweedie regression models that leverage the value of data fromboth partieswithout exchanging *** assessment results of the scheme approach those of the Tweedie regressionmodel learned fromcentralized data,and outperformthe Tweedie regressionmodel learned independently by a single party.

关键词： Rate setting Tweedie distribution generalized linear models federated learning homomorphic encryption

Efficient adiabatic silicon-on-insulator waveguide taper

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Photonics Research 2014年第3期2卷 S0041-S0044页

作者： Yunfei Fu Tong Ye weijie tang Tao Chu State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

A silicon-on-insulator-based adiabatic waveguide taper with a high coupling efficiency and small footprint is *** taper was designed to reduce the incidence of mode conversion to higher-order and radiation modes inside the *** connecting a 0.5-μm-wide output waveguide and a 12-μm-wide input waveguide of a grating coupler,a compact 120-μm-long taper was demonstrated,achieving a transmission of 98.3%.Previously,this transmission level could only be achieved using a conventional linear taper with a length of more than 300μm.

关键词： waveguide taper adiabatic

Experimental Study of Electrical‑Assisted Nanomachining of Monocrystalline Copper Using Customized Tungsten Tip

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Nanomanufacturing and Metrology 2024年第2期7卷 60-75页

作者： Tao Wang Yanling Tian Zhilai Lu weijie Wang Zhao Zhang Guangwei Zhu Hui tang Dawei Zhang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China School of Engineering University of WarwickCoventry CV47ALUK State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China

As a promising micro/nanofabrication method,electrical-assisted nanomachining has obtained substantial attention due to its high material removal rate and attainable superior surface *** this study,a rectangular wave electrical signal was applied for nanomachining by a customized tungsten *** to the coupling effect between the electric field and mechanical force,the cutting depth of the machined grooves can be *** electrical-assisted groove processing,a depth of 270 nm and an aspect ratio of 0.6 on the copper sample can be *** influence of operation parameters including applied voltage,frequency,duty ratio,normal force and cutting speed on the machining performance was investigated in terms of the groove depth,width,aspect ratio,and surface *** potential machining mechanisms should be a combination of electric field force,nanoscale electric discharge,electric contact thermal effects,possible annealing behavior,and scraping and plowing actions induced by mechanical forces.

关键词： Tip-based nanofabrication Electrical-assisted machining Nanoscale scratching Machining parameters