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主从结构的交直流混合微电网综合控制策略

分布式能源 2018年第3期3卷 42-50页

作者：汪宝匡洪海郑丽平丁晓薇湖南工业大学电气与信息工程学院湖南株洲412007

考虑到单一交流微电网与单一直流微电网在系统控制与便捷交直流负荷供电方面的不足,针对一种主从结构的交直流混合微电网,将交流侧储能变流器设置为主控单元,联络变流器设置为从控单元。在分析系统各单元控制策略的基础上,基于系统功率... 详细信息

考虑到单一交流微电网与单一直流微电网在系统控制与便捷交直流负荷供电方面的不足,针对一种主从结构的交直流混合微电网,将交流侧储能变流器设置为主控单元,联络变流器设置为从控单元。在分析系统各单元控制策略的基础上,基于系统功率平衡进行了系统综合控制策略的研究。通过系统储能装置的功率平抑,采用相应的控制策略实现了交直流混合微电网在不同运行模式下系统的功率稳定,并通过仿真对所述模型及其控制策略进行了仿真验证。

关键词：主从结构交直流混合微电网综合控制

空心玻璃微珠添加量对有机硅高导热灌封胶性能影响的实验研究

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塑料包装 2024年第6期34卷 30-33页

作者：丁小卫欧阳俊花李艺基深圳市安品有机硅材料有限公司广东深圳518100

本实验以双组分加成型硅凝胶为主要原料,氧化铝为导热填料,添加空心玻璃微珠、铂金催化剂等制得低介电有机硅高导热灌封胶。研究了添加不同质量百分比的空心玻璃微珠增强导热灌封胶的力学性能、体积电阻率、导热系数、击穿电压和低介电... 详细信息

本实验以双组分加成型硅凝胶为主要原料,氧化铝为导热填料,添加空心玻璃微珠、铂金催化剂等制得低介电有机硅高导热灌封胶。研究了添加不同质量百分比的空心玻璃微珠增强导热灌封胶的力学性能、体积电阻率、导热系数、击穿电压和低介电常数。结果表明:随着空心玻璃微珠添加量的逐渐上升,灌封胶的黏度呈现逐渐上升趋势,导热系数、比重、介电常数等逐渐降低;当空心玻璃微珠的添加量达到3.0%时,灌封胶的导热系数降低至0.9W/mK,介电常数达到4.186(1mhz)。

关键词：导热灌封胶有机硅低介电常数空心玻璃微珠

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低压电器产品的通信测试

低压电器 2012年第20期 54-56页

作者：苑佳郑静丁小伟李新强上海电器设备检测所上海200063

搭建了低压电器通信测试的框架,包括通信协议测试、通信规范测试和"四遥"通信功能验证,并已着手建设检测能力,为低压电器产品从传统的分立元器件向可通信、智能化、可集成化方向发展提供良好的检测服务。

关键词：低压电器通信测试总线协议通信规范

基于Modbus协议的智能型低压电器自动测试系统

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低压电器 2013年第3期 47-49页

作者：丁小伟郑静苑佳李新强上海电器设备检测所上海200063

针对智能型低压电器的通信功能检测,开发了一个自动测试系统。该系统不仅能对采用Modbus协议的智能型低压电器进行协议一致性测试,而且可以进行遥测、遥信、遥控、遥调功能测试。以VK60控制与保护开关电器为例,演示了测试方法。

关键词： Modbus协议一致性测试四遥功能测试自动测试系统

基于历史秃山航空影像获取高精度DEM关键技术的应用研究

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测绘与空间地理信息 2019年第11期42卷 129-132页

作者：丁小蔚邓廷起徐大展江瑞浙江华云电力工程设计咨询有限公司浙江杭州310014 浙江省第二测绘院浙江杭州310012

历史航空影像真实地反映了各个历史时期的地表形态、社会经济与环境状况等信息,客观有效地记录了地表演化变迁过程。早期历史航片山地植被覆盖率低,城市建筑物相对稀疏,通过航测法获取的DEM数据理论上可以直接反映山地的地形,且精度会... 详细信息

历史航空影像真实地反映了各个历史时期的地表形态、社会经济与环境状况等信息,客观有效地记录了地表演化变迁过程。早期历史航片山地植被覆盖率低,城市建筑物相对稀疏,通过航测法获取的DEM数据理论上可以直接反映山地的地形,且精度会优于现今植被茂密、覆盖率高的数码航片获取的DEM精度。本文基于区域网空三加密、密集匹配以及滤波分类等关键技术,对1979年浙江省某市北部山地区域秃山地表航空影像资料进行处理,获取高精度DEM数据,并通过与机载激光雷达获取的点云数据以及野外实地高程点测量值进行比较。结果表明,通过历史秃山地表航空影像获取的DEM数据山地精度优于0.8 m。

关键词：历史航片秃山地表数字高程模型密集匹配滤波分类

基于高通量测序的花马盐湖原核微生物及其耐盐基因

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微生物学报 2018年第10期58卷 1743-1753页

作者：刘开辉张波丁小维杨学英邓百万兰阿峰彭浩牛明月米洋陕西理工大学生物科学与工程学院陕西汉中723001

【目的】揭示陕北花马盐湖沉积物原核微生物群落组成,并分析其潜在的耐盐功能基因。【方法】构建盐湖沉积物宏基因组16S r RNA文库和fosmid文库,利用Illumina HiSeq高通量测序及生物信息技术分析细菌古菌群落组成和耐盐菌株(5-5)外源宏... 详细信息

【目的】揭示陕北花马盐湖沉积物原核微生物群落组成,并分析其潜在的耐盐功能基因。【方法】构建盐湖沉积物宏基因组16S r RNA文库和fosmid文库,利用Illumina HiSeq高通量测序及生物信息技术分析细菌古菌群落组成和耐盐菌株(5-5)外源宏基因组的潜在耐盐基因。【结果】获得18978条有效的16Sr RNA序列,共5221个OTUs,包括23个门,155个属,其中广古菌门(Euryarchaeota)和变形菌门(Proteobacteria)为优势菌门,盐杆状菌属(Halorhabdus)、盐红菌属(Halorubrum)及假单胞菌属(Pseudomonas)等16个属为优势属,以及嗜盐单胞菌属(Halomonas)、冷弯菌属(Psychroflexus)及不动细菌属(Acinetobacter)等139个属为非优势属。从4126个fosmid文库菌株中筛选出37株耐盐菌株,其中菌株5-5、2E4和2F4对不同浓度的NaCl、CuSO_4、ZnSO_4及CdSO_4具有耐受性,从5-5的外源宏基因组序列中获得61个Unigene,其中12个Unigene的同源基因编码的蛋白质如无机焦磷酸酶、转座酶、亚碲酸钾抗性蛋白及钙调蛋白等广泛参与其他生物的耐盐逆境。【结论】盐湖沉积物中蕴藏着丰富多样的细菌古菌类群以及潜在耐盐功能基因资源。

关键词：盐湖宏基因组文库原核微生物耐盐基因高通量测序

Surface integrity evolution during creep feed profile grinding ofγ-TiAl blade tenon

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Chinese Journal of Aeronautics 2024年第8期37卷 496-512页

作者： Tao CHEN xiaowei WANG Biao ZHAO Wenfeng ding Jiuhua XU National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Gamma titanium-aluminum(γ-TiAl)intermetallic compounds are increasingly used in manufacturing key hot-end components(e.g.,blade tenon)in aero engines due to their high specific strength and lightweight *** feed profile grinding(CFPG)as a crucial precision process that is applied to produce the final profile of the blade ***,sudden surface burns and microcracks of machined c-TiAl blade tenon often occur because of its low plasticity and high strength during grinding processes,leading to poor surface *** this work,CFPG experiments based on the profile characteristics ofγ-TiAl blade tenon were performed and an associated undeformed chip thickness model considering grain–workpiece contact condition was established to explore the evolution of the surface ***,the surface integrity was analyzed at different positions of the blade tenon in terms of surface roughness and morphology,metallographic structure,microhardness,and residual *** show that the profile characteristics of blade tenon have a significant influence on machined surface integrity because of the thermomechanical effect at various detecting *** residual stress was established based on the undeformed chip thickness model considering the profile structure,with a prediction error of 10%–15%.The thermomechanical effect is more obvious at the bottom area,where the surface roughness,work hardening degree,and subsurface plastic deformation range are the largest,while the values at the bevel area are the *** on the undeformed chip thickness model,a residual stress finite element simulation was conducted by employing thermomechanical coupled *** addition,the error between the simulation and the experiment was between 10%–15%.Strain and strain rate equations were established through the relationship between material displacement and *** average strain and strain rate of the ground surface when ap is 1.0 mm are 18.8%and 33.2%l

关键词： Gamma titanium-aluminum intermetallic compounds Blade tenon Creep feed profile grinding Surface integrity Thermomechanical effect

Prediction of maximum upward displacement of shield tunnel linings during construction using particle swarm optimization-random forest algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 1-17页

作者： xiaowei YE Xiaolong ZHANG Yanbo CHEN Yujun WEI Yang ding MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Zhejiang Engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou310015China

During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield *** floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the *** this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel *** mechanism and factors causing upward movement of the tunnel lining are comprehensively *** input variables were selected according to results from analysis of influencing *** prediction performance of two models,PSO-RF and RF(default)were *** Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of *** PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.

关键词： Random forest(RF) Particle swarm optimization(PSO) Upward displacement of lining Machine learning prediction Shieldtunneling construction

Short-term tunnel-settlement prediction based on Bayesian wavelet:a probability analysis method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第11期24卷 960-977页

作者： Yang ding xiaowei YE Zhi ding Gang WEI Yunliang CUI Zhen HAN Tao JIN Key Laboratory of Safe Construction and Intelligent Maintenance for Urban Shield Tunnels of Zhejiang Province Hangzhou City UniversityHangzhou 310015China Zhejiang Engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou 310015China Department of Civil Engineering Hangzhou City UniversityHangzhou 310015China Department of Civil Engineering Zhejiang UniversityHangzhou 310058China Nanjing Metro Operation Co. Ltd.Nanjing 210012China

As urbanization accelerates,the metro has become an important means of *** the safety problems caused by metro construction,ground settlement needs to be monitored and predicted regularly,especially when a new metro line crosses an existing *** this paper,we propose a settlement-probability prediction model with a Bayesian emulator(BE)based on the Gaussian prior(GP),that is,a *** addition,considering the distortion characteristics of monitoring data,the data is denoised using wavelet decomposition(WD),so the final prediction model is *** particular,the effects of different prediction ratios and moving windows on prediction performance are explored,and the optimal number of moving windows is *** addition,the predicted value for GPBE based on the original data is compared with the predicted value for WD-GPBE based on the denoised *** year of settlement-monitoring data collected by a structural health monitoring(SHM)system installed on the Nanjing Metro is used to demonstrate the effectiveness of WDGPBE and GPBE for predicting settlement.

关键词： Metro construction Settlement probability prediction Structural health monitoring(SHM) Wavelet denoising Gaussian prior(GP) Bayesian emulator(BE)