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Percentile-based Neighborhood Precipitation Verification and Its Application to a Landfalling Tropical Storm Case with Radar Data Assimilation

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Advances in Atmospheric Sciences 2015年第11期32卷 1449-1459页

作者： zhu Kefeng YANG Yi Ming xue Key Laboratory of Mesoscale Severe Weather/Ministry of Education and School of Atmospheric Sciences Nanjing University Center for Analysis and Prediction of Storms University of Oklahoma College of Atmospheric Sciences Lanzhou University

The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thresholds in terms of the percentiles of overall precipitation instead of fixed threshold values. The impact of intensity forecast bias on the calculated threat score is reduced. The method is tested with the forecasts of a tropical storm that re-intensified after making landfall and caused heavy flooding. The forecasts are produced with and without radar data assimilation. The forecast with assimilation of both radial velocity and reflectivity produce precipitation patterns that better match observations but have large positive intensity bias. When using fixed thresholds, the neighborhood threat scores fail to yield high scores for forecasts that have good pattern match with observations, due to large intensity bias. In contrast, the percentile-based neighborhood method yields the highest score for the forecast with the best pattern match and the smallest position error. The percentile-based method also yields scores that are more consistent with object-based verifications, which are less sensitive to intensity bias, demonstrating the potential value of percentile-based verification.

关键词： neighborhood precipitation threat score percentile-based verification radar data assimilation

Stent-grafts for the treatment of TIPS dysfunction:Fluency stent vs Wallgraft stent

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World Journal of Gastroenterology 2013年第30期19卷 5000-5005页

作者： xue-Feng Luo ling Nie zhu Wang Jiaywei Tsauo ling-Jun Liu Yang Yu Biao Zhou Cheng-Wei Tang Xiao Li Department of Gastroenterology West China HospitalSichuan University Department of Interventional Radiology West China HospitalSichuan University Department of Pathology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To evaluate the clinical efficacy of an expanded polytetrafluoro-ethylene-covered Fluency stent compared with that of a polyethylene terephthalate-covered Wallgraft stent for the management of transjugular intrahepatic portosystemic shunt(TIPS)***:A retrospective review of patients who underwent TIPS revision with stent-grafts between May 2007 and June 2011 was *** patients were divided into two groups according to the stentgrafts implanted:the Fluency stent(Bard Incorporated,Karlsruhe,Germany)and the Wallgraft stent(Boston Scientific,Galway,Ireland).The primary patency rates were calculated and compared using the Kaplan-Meier ***:A total of 73 patients were evaluated in this study:33 with Fluency stents and 40 with Wallgraft *** primary patency rates at 12 and 24 mo were 91% and 85%,respectively,in the Fluency stent group and 78% and 63%,respectively,in the Wallgraft stent *** primary shunt patency rates after TIPS revision were significantly better with the Fluency stent than with the Wallgraft stent(P = 0.033).CONCLUSION:TIPS revision with the Fluency stent has higher medium-term patency rates than that with the Wallgraft stent.

关键词： Expanded polytetrafluoroethylene-covered stent-grafts Transjugular intrahepatic portosystemic shunt dysfunction Revision Fluency

NEW HYDRAULIC ACTUATOR'S POSITION SERVOCONTROL STRATEGY

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Chinese Journal of Mechanical Engineering 2007年第5期20卷 46-53页

作者： KE Zunrong zhu Yuquan ling Xuan School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074. China

A new hydraulic actuator-hydraulic muscle （HM） is described, and the actuator＇s features and applications are analyzed, then a position servocontrol system in which HM is main actuator is set up. The mathematical model of the system is built up and several control strategies are discussed. Based on the mathematical model, simulation research and experimental investigation with subsection PID control, neural network self-adaptive PID control and single neuron self-adaptive PID control adopted respectively are carried out, and the results indicate that compared with PID control, neural network self-adaptive PID control and single neuron self-adaptive PID control don＇t need controlled system＇s accurate model and have fast response, high control accuracy and strong robustness, they are very suitable for HM position servo control system.

关键词： Hydraulic muscle (HM) Position servocontrol Control strategies Subsection PID control Neural network self-adaptive PID control Single neuron self-adaptive PID control

Gel-state polybenzimidazole proton exchange membranes with flexible alkyl sulfonic acid side chains for a wider operating temperature range(25–240 ℃)

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Journal of Energy Chemistry 2023年第10期85卷 91-101,I0005页

作者： Taizhong zhu Danyi zhu Jiazhen Liang Liang Zhang Fei Huang Lixin xue Center for Membrane Separation and Water Science&Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014ZhejiangChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035ZhejiangChina Received 18 April 2023Revised 30 May 2023Accepted 31

High-temperature proton exchange membrane fuel cells(HT-PEMFC) possess distinct technical advantages of high output power, simplified water/heat management, increased tolerance to fuel impurities and diverse fuel sources, within the temperature range of 120–200 ℃. However, for practical automobile applications, it was crucial to broaden their low-temperature operating window and enable cold start-up capability. Herein, gel-state phosphoric acid(PA) doped sulfonated polybenzimidazole(PBI) proton exchange membranes(PEMs) were designed and synthesized via PPA sol-gel process and in-situ sultone ring-opening reactions with various proton transport pathways based on absorbed PA, flexible alkyl chain connected sulfonic acid groups and imidazole sites. The effects of flexible alkyl sulfonic acid side chain length and content on PA doping level, proton conductivity, and membrane stability under different temperature and relative humidity(RH) were thoroughly investigated. The prepared gel-state membranes contained a self-assembled lamellar and porous structure that facilitated the absorption of a large amount of PA with rapid proton transporting mechanisms. At room temperature, the optimized membrane exhibited a proton conductivity of 0.069 S cm^(-1), which was further increased to 0.162 and 0.358 S cm^(-1)at 80 and 200 ℃, respectively, without additional humidification. The most significant contribution of this work was demonstrating the feasibility of gel-state sulfonated PBI membranes in expanding HT-PEMFC application opportunities over a wider operating range of 25 to 240 ℃.

关键词： Wide temperature range Proton exchange membrane Fuel cell Gel-state Polybenzimidazole

Viscoelastic Property Evolution of Thermoplastic Polyurethane during Annealing Treatment and Its Correlation with Segmental Crystallization

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Chinese Journal of Polymer Science 2024年第12期42卷 1976-1985,I0010页

作者： Jian-Wen Shan Yan-Bo zhu ling-ling Ni Peng-Ju Pan State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310058China Department of Polymer Science and Engineering Zhejiang UniversityHangzhou310058China

Viscoelastic properties of thermoplastic polyurethane(TPU)is of fundamental importance for its *** this work,we prepared different TPUs from polycaprolactone(PCL)diol,diphenylmethane-4,4′-diisocyanate(MDI),and 1,4-butanediol(BDO),and investigated the viscoelastic behavior of three TPUs with different hard segment content during thermal annealing *** storage modulus(G′)of TPU increases over time in a medium annealing temperature(T_(a))region,but remains unchanged at both high and low temperature *** growth of loss modulus(G″)over time is slower than that of G′.At medium T_(a),both G′and G″increase during the repeating frequency(ω)sweep,due to the gradual crystallization of hard *** indicates that the crystallites primarily restrain the relaxation of unit with large *** increments of G′and G″are weakened when the content of hard segment in TPU is *** TPU with high content of hard segments,a complete high elastic platform with a width of 3 orders of magnitude was observed only through one frequency scan test at medium T_(a).In addition,the crystallites of hard segments grow up continuously during frequency scan test(isothermal annealing treatment)and cause the extreme increase in G′and G″withωin lowωregion.

关键词： Thermoplastic polyurethane Viscoelastic properties Annealing Crystalization

The Viability Property of Controlled Jump Diffusion Processes

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Acta Mathematica Sinica,English Series 2008年第8期24卷 1351-1368页

作者： Shi Ge PENG xue Hong zhu Institute of Mathematics Shandong University Ji'nan 250100 P. R. China School of Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

In this paper, we first give a comparison theorem of viscosity solution to some nonlinear second order integrodifferential equation. And then using the comparison theorem, we obtain a necessary and sufficient condition for the viability property of some controlled jump diffusion processes which can keep the solution within a constraint K.

关键词： viability integrodifferential equation viscosity solution

g-Besselian Frames in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2117-2130页

作者： Ming ling DING Yu Can zhu College of Computer and Information Fujian Agriculture and Forestry University Fuzhou 350002 P. R. China Department of Mathematics Fuzhou University Fuzhou 350108 P. R. China

In this paper, we introduce the concept of a g-Besselian frame in a Hilbert space and discuss the relations between a g-Besselian frame and a Besselian frame. We also give some characterizations of g-Besselian frames. In the end of this paper, we discuss the stability of g-Besselian frames. Our results show that the relations and the characterizations between a g-Besselian frame and a Besselian frame are different from the corresponding results of g-frames and frames.

关键词： g-frame Besselian frame g-Besselian frame stability

Proteomic analysis of blast-resistant near-isogenic lines derived from japonica rice, var. Yunyin, infected with Magnaporthe oryzae

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Chinese Science Bulletin 2014年第32期59卷 4312-4322页

作者： Weimin xue Xiaohui Mao Yidong Wei Lian ling Yongsheng zhu Shuilin He Jianfu Zhang Huaan Xie Rice Research Institute Fujian Academy of Agricultural Sciences National Engineering Laboratory of Rice South Base of National Key Laboratory of Hybrid Rice of China College of Crop Science Fujian Agriculture and Forestry

Rice blast is one of the most devastating diseases in the world and outbreaks occur *** differences in protein expression between blast resistant and susceptible near-isogenic lines(NILs)of japonica rice *** infected with Magnaporthe oryzae were analyzed using proteomics,indicated that 67 different proteins were identified from 75 obtained proteins using the matrixassisted laser desorption/ionization time-of-flight mass spectrometry *** specific expression proteins,43 up-regulated proteins and 17 down-regulated proteins were identified among the 67 *** bioinformatical analysis demonstrated that these 67 different proteins were involved in many biological physiological processes including five proteins related to photosynthesis,25 proteins related to metabolism,six proteins related to antioxidants,10 proteins related to protein synthesis and modification,five proteins related to signal transduction,four proteins related to adversity stress and 12 non-functional *** identified proteins were directly or indirectly related to *** proteins related to different physiological processes were *** cDNA sequences were predicted and their expression patterns were analyzed using real-time PCR,demonstrated that the genes would response to *** and the response blindingly different between blast resistant and blast susceptible NILs.

关键词：蛋白质组学近等基因系稻瘟病菌 VAR 粳稻学分感染基质辅助激光解吸

Molecular engineering of an electron-transport triarylphosphine oxide-triazine conjugate toward high-performance phosphorescent organic light-emitting diodes with remarkable stability

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Science China Chemistry 2020年第7期63卷 904-910页

作者： ling-ling Chen ling Peng Lin-Ye Wang Xu-Hui zhu Jian-Hua Zou Junbiao Peng State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and DevicesSouth China University of Technology(SCUT)Guangzhou 510640China Guangzhou New Vision Opto-Electronic Technology Co. LtdGuangzhou 510730China

Organic electron-transport materials are an essential component to boost performances and stability of organic light-emitting diodes. We present a robust organic electron-transport compound 3-(6-(3-(4,6-bis(4-biphenylyl)-1,3,5-triazin-2-yl)phenyl)pyridin-2-yl)phenyldiphenylphosphine oxide by facilely coupling the triphenylphosphine oxide moiety to the 2-phenyl-4,6-bis(4-biphenylyl)-1,3,5-triazine unit via a 2,6-pyridinylene linker. It is well soluble in weakly polar solvents and possesses a high Tg of 123 ℃ with an exceptional Td≈470 ℃ at 1% weight loss and deep HOMO/LUMO levels of ca.-6.45/-3.06 eV. The phosphorescent spectrum measured in solid state at 77 K reveals a notable triplet energy of 2.88 eV. n-Doping with 8-hydroxyquinolatolithium(Liq) produces the electron mobility value of 4.66×10-5–3.21×10-4 cm2 V-1 s-1@(2–5)×105 V ***, the contrasting solubility of the bromo reaction intermediate and the new compound in alcoholic solvents facilitates separation. The characterizations of bottom-and top-emission green phosphorescent OLEDs involving this single Liq-doped electron-transport layer reveal long stability. In particular, the latter provides outstanding performances with 77.4 cd A–1(corresponding to an EQE of 18.7%) and 86.8 lm W–1@ca. 1000 cd m-2, based on the green emitter bis(2-phenylpyridine)(2-(4-methyl-3-phenylphenyl)pyridine)iridium(Ⅲ). Moreover, driven by a constant current for ca. 640 h, the initial luminance of 1000 cd m–2 appears almost no decay.

关键词： electron-transport materials halogen impurities heterocycles lifetime phosphine oxides