Blends of PC and PPSQ (A) with high M-w and good ladderlike regularity or PPSQ(B) with low M-w and more defective Si-atoms in its structure have been prepared by solution casting. The dispersed spheres (PPSQ(A)-rich) ...Blends of PC and PPSQ (A) with high M-w and good ladderlike regularity or PPSQ(B) with low M-w and more defective Si-atoms in its structure have been prepared by solution casting. The dispersed spheres (PPSQ(A)-rich) are unevenly dispersed in the continuous PC-rich phase and there is no phase-inversion as PPSQ(A) content increases when the percentage of PPSQ(A) is not more than 70%. PPSQ(B)-rich spheres are evenly dispersed in the continuous phase (PC-rich) and phase-inversion occurs when PPSQ(B) percentage is up to 70%. T-g of PPSQ(A)/PC or PPSQ(B)/PC at some compositions are lower than that of pure PC due to the enlarged free-volume of PC-rich phase because some spheres of rigid PPSQ chains are included in the PC-rich phase. PC and PPSQ(A) or PPSQ(B) are partially compatible. The compatibility of PC and PPSQ(B) is better than that of PC and PPSQ(A) with high M-w and good ladderlike regularity. Heat history has some influence on the T(g)s and compatibility of PPSQ(A)/PC and PPSQ(B)/PC blends.展开更多
Based on the observations of a squall line on 11 May 2020 and stratiform precipitation on 6 June 2020 from two X-band dual-polarization phased array weather radars(DP-PAWRs)and an S-band dual-polarization Doppler weat...Based on the observations of a squall line on 11 May 2020 and stratiform precipitation on 6 June 2020 from two X-band dual-polarization phased array weather radars(DP-PAWRs)and an S-band dual-polarization Doppler weather radar(CINRAD/SA-D),the data reliability of DP-PAWR and its ability to detect the fine structures of mesoscale weather systems were assessed.After location matching,the observations of DP-PAWR and CINRAD/SA-D were compared in terms of reflectivity(Z_(H)),radial velocity(V),differential reflectivity(Z_(DR)),and specific differential phase(K_(DP)).The results showed that:(1)DP-PAWR has better ability to detect mesoscale weather systems than CINRAD/SAD;the multi-elevation-angles scanning of the RHI mode enables DP-PAWR to obtain a wider detection range in the vertical direction.(2)DP-PAWR’s Z_(H)and V structures are acceptable,while its sensitivity is worse than that of CINRAD/SA-D.The Z H suffers from attenuation and the Z_(H)area distribution is distorted around strong rainfall regions.(3)DP-PAWR’s Z_(DR)is close to a normal distribution but slightly smaller than that of CINRAD/SA-D.The K_(DP)products of DP-PAWR have much higher sensitivity,showing a better indication of precipitation.(4)DP-PAWR is capable of revealing a detailed and complete structure of the evolution of the whole storm and the characteristics of particle phase variations during the process of triggering and enhancement of a small cell in the front of a squall line,as well as the merging of the cell with the squall line,which cannot be observed by CINRAD/SA-D.With its fast volume scan feature and dual-polarization detection capability,DP-PAWR shows great potential in further understanding the development and evolution mechanisms of meso-γ-scale and microscale weather systems.展开更多
A set of device is designed based on PC to realize the functions of traditional potentiostats in the phase ana1ysis of galvanochemistry. In the device, A/D and D/A conversion is used to measure the electrode potential...A set of device is designed based on PC to realize the functions of traditional potentiostats in the phase ana1ysis of galvanochemistry. In the device, A/D and D/A conversion is used to measure the electrode potential and convert the voltage for outPut; specific program runs in the PC to regulate and control the system. The effect of the proportion factor Kp on the control variation is researched through certain experiment. Two experiments, the control of electrolysis in constant poteniial and the determination of polarization curves, are designed to test and evaluate the effectiveness of the device. The experimemel results show that the variation between the actualanode potential and the target potential could be controlled to below 1 mV if Kp is set to an appropriate value.展开更多
随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase co...随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase compensation based active disturbance rejection control,PC-ADRC)方法。首先,阐述过热汽温系统的工作原理和控制难点。然后,采用低频近似法详细推导相位补偿(phase compensation,PC)网络模型,提出采用PC网络对模型动态特性进行补偿,得到等效降阶模型的简化思路。为便于工程应用,给出PC-ADRC系统的简单实现方法和等效模型分析。最后,对PC-ADRC系统的稳定性和鲁棒性进行研究。理论分析和仿真结果表明,所提出的PC-ADRC系统能有效提升高阶过程控制系统的鲁棒性和快速响应能力。展开更多
针对多模态遥感影像存在非线性辐射畸变的问题,本文提出了一种结合相位对称特征与基于排序局部自相似性的多模态遥感影像匹配方法.首先,利用影像的局部相位信息构造相位对称图,在此基础上利用加速分段测试特征提取算法(features from ac...针对多模态遥感影像存在非线性辐射畸变的问题,本文提出了一种结合相位对称特征与基于排序局部自相似性的多模态遥感影像匹配方法.首先,利用影像的局部相位信息构造相位对称图,在此基础上利用加速分段测试特征提取算法(features from accelerated segment test,FAST)对相位对称图进行特征提取.然后结合基于排序的局部自相似性与相位一致性构造一种新的特征描述符RPCLSS(combining rank,phase congruency and local self-similarity descriptor).最后利用快速抽样一致性算法(fast sample consensus,FSC)进行误匹配点剔除.将本文方法在公开的多源遥感影像数据集上与现有的5种先进匹配方法进行对比实验.实验结果表明,本文方法在正确匹配点数量、匹配精度和匹配正确率方面,优于现有的先进多模态遥感影像匹配方法.展开更多
基金This work was supported by Fund of Head of College of Chemistry,Shandong University.
文摘Blends of PC and PPSQ (A) with high M-w and good ladderlike regularity or PPSQ(B) with low M-w and more defective Si-atoms in its structure have been prepared by solution casting. The dispersed spheres (PPSQ(A)-rich) are unevenly dispersed in the continuous PC-rich phase and there is no phase-inversion as PPSQ(A) content increases when the percentage of PPSQ(A) is not more than 70%. PPSQ(B)-rich spheres are evenly dispersed in the continuous phase (PC-rich) and phase-inversion occurs when PPSQ(B) percentage is up to 70%. T-g of PPSQ(A)/PC or PPSQ(B)/PC at some compositions are lower than that of pure PC due to the enlarged free-volume of PC-rich phase because some spheres of rigid PPSQ chains are included in the PC-rich phase. PC and PPSQ(A) or PPSQ(B) are partially compatible. The compatibility of PC and PPSQ(B) is better than that of PC and PPSQ(A) with high M-w and good ladderlike regularity. Heat history has some influence on the T(g)s and compatibility of PPSQ(A)/PC and PPSQ(B)/PC blends.
基金Guangdong Basic and Applied Basic Research Foundation(2020A1515010602)Special Fund of China Meteorological Administration for Innovation and Development(CXFZ2022J063)+4 种基金Special Fund for Forecasters of China Meteorological Administration(CMAYBY2019-082)Science and Technology Planning Program of Guangzhou(201903010101)Key-Area Research and Development Program of Guangdong Province(2020B1111200001)National Natural Science Foundation of China(42075190,41875182)Radar Application and Shortterm Severe-weather Predictions and Warnings Technology Program(GRMCTD202002)。
文摘Based on the observations of a squall line on 11 May 2020 and stratiform precipitation on 6 June 2020 from two X-band dual-polarization phased array weather radars(DP-PAWRs)and an S-band dual-polarization Doppler weather radar(CINRAD/SA-D),the data reliability of DP-PAWR and its ability to detect the fine structures of mesoscale weather systems were assessed.After location matching,the observations of DP-PAWR and CINRAD/SA-D were compared in terms of reflectivity(Z_(H)),radial velocity(V),differential reflectivity(Z_(DR)),and specific differential phase(K_(DP)).The results showed that:(1)DP-PAWR has better ability to detect mesoscale weather systems than CINRAD/SAD;the multi-elevation-angles scanning of the RHI mode enables DP-PAWR to obtain a wider detection range in the vertical direction.(2)DP-PAWR’s Z_(H)and V structures are acceptable,while its sensitivity is worse than that of CINRAD/SA-D.The Z H suffers from attenuation and the Z_(H)area distribution is distorted around strong rainfall regions.(3)DP-PAWR’s Z_(DR)is close to a normal distribution but slightly smaller than that of CINRAD/SA-D.The K_(DP)products of DP-PAWR have much higher sensitivity,showing a better indication of precipitation.(4)DP-PAWR is capable of revealing a detailed and complete structure of the evolution of the whole storm and the characteristics of particle phase variations during the process of triggering and enhancement of a small cell in the front of a squall line,as well as the merging of the cell with the squall line,which cannot be observed by CINRAD/SA-D.With its fast volume scan feature and dual-polarization detection capability,DP-PAWR shows great potential in further understanding the development and evolution mechanisms of meso-γ-scale and microscale weather systems.
文摘A set of device is designed based on PC to realize the functions of traditional potentiostats in the phase ana1ysis of galvanochemistry. In the device, A/D and D/A conversion is used to measure the electrode potential and convert the voltage for outPut; specific program runs in the PC to regulate and control the system. The effect of the proportion factor Kp on the control variation is researched through certain experiment. Two experiments, the control of electrolysis in constant poteniial and the determination of polarization curves, are designed to test and evaluate the effectiveness of the device. The experimemel results show that the variation between the actualanode potential and the target potential could be controlled to below 1 mV if Kp is set to an appropriate value.
文摘随着可再生能源接入电网比例的逐步增大,热力发电厂需要应对更加频繁、更大范围的负荷变化,给电厂的高阶大惯性过热汽温过程的控制带来严峻的挑战。为此,文中针对一类高阶大惯性过热汽温过程,提出一种基于相位补偿的自抗扰控制(phase compensation based active disturbance rejection control,PC-ADRC)方法。首先,阐述过热汽温系统的工作原理和控制难点。然后,采用低频近似法详细推导相位补偿(phase compensation,PC)网络模型,提出采用PC网络对模型动态特性进行补偿,得到等效降阶模型的简化思路。为便于工程应用,给出PC-ADRC系统的简单实现方法和等效模型分析。最后,对PC-ADRC系统的稳定性和鲁棒性进行研究。理论分析和仿真结果表明,所提出的PC-ADRC系统能有效提升高阶过程控制系统的鲁棒性和快速响应能力。
文摘针对多模态遥感影像存在非线性辐射畸变的问题,本文提出了一种结合相位对称特征与基于排序局部自相似性的多模态遥感影像匹配方法.首先,利用影像的局部相位信息构造相位对称图,在此基础上利用加速分段测试特征提取算法(features from accelerated segment test,FAST)对相位对称图进行特征提取.然后结合基于排序的局部自相似性与相位一致性构造一种新的特征描述符RPCLSS(combining rank,phase congruency and local self-similarity descriptor).最后利用快速抽样一致性算法(fast sample consensus,FSC)进行误匹配点剔除.将本文方法在公开的多源遥感影像数据集上与现有的5种先进匹配方法进行对比实验.实验结果表明,本文方法在正确匹配点数量、匹配精度和匹配正确率方面,优于现有的先进多模态遥感影像匹配方法.
