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Asymptotic Analysis of Lattice Boltzmann Outflow Treatments

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Communications in Computational Physics 2011年第5期9卷 1117-1127页

作者： Michael Junk zhaoxia yang FB Mathematik und Statistik Universität KonstanzPostfach D19478457 KonstanzGermany

We show the methodology and advantages of asymptotic analysis when applied to lattice Boltzmann outflow *** the one hand,one can analyze outflow algorithms formulated directly in terms of the lattice Boltzmann variables,like the extrapolation method,to find the induced outflow conditions in terms of the NavierStokes *** the other hand,one can check the consistency and accuracy of lattice Boltzmann outflow treatments to given hydrodynamic outflow conditions like the Neumann or average pressure *** example how the gained insight can be used,we propose an improvement of the well known extrapolation method.

关键词： Outflow condition asymptotic analysis lattice Boltzmann method

Analysis and Invariant Properties of a Lattice Boltzmann Method

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Advances in Applied Mathematics and Mechanics 2010年第5期2卷 640-669页

作者： Michael Junk zhaoxia yang FB Mathematik und Statistik Universit¨at KonstanzPostfach D19478457 KonstanzGermany

We investigate a two-relaxation-time(TRT)lattice Boltzmann algorithm with the asymptotic analysis *** results are used to analyze invariance properties of the *** particular,we focus on time dependent Stokes and Navie... 详细信息

关键词： Two-relaxation-time LBM invariance property asymptotic analysis

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消毒供应中心卓越质量评价指标体系的构建

国际护理学杂志 2024年第6期43卷 961-966页

作者：王俊亭杨朝霞山东第一医科大学第二附属医院消毒供应中心泰安271000 山东第一医科大学第二附属医院护理部泰安271000

目的旨在以卓越绩效模型为基础框架,构建消毒供应中心质量评价指标体系,为科学评价消毒供应中心质量提供工具。方法依据卓越绩效模型和我国消毒供应中心质量管理现状,进行两轮德尔菲专家函询,构建基于卓越绩效模型的消毒供应中心质量评... 详细信息

目的旨在以卓越绩效模型为基础框架,构建消毒供应中心质量评价指标体系,为科学评价消毒供应中心质量提供工具。方法依据卓越绩效模型和我国消毒供应中心质量管理现状,进行两轮德尔菲专家函询,构建基于卓越绩效模型的消毒供应中心质量评价指标体系。结果构建的评价指标体系,共包含一级指标6个、二级指标27个、三级指标62个。专家函询的专家权威系数为0.892,两轮专家函询的肯德尔和谐系数(Kendall W)分别为一级指标0.142、0.197,二级指标0.185、0.206,三级指标0.199、0.202,变异系数(CV)均值分别为一级指标0.119、0.083,二级指标0.111、0.098,三级指标0.121、0.108。经χ^(2)检验,差异均有统计学意义(均P<0.05)。结论本研究构建出的消毒供应中心质量评价指标体系。函询专家积极性高,权威程度高,协调性好,指标构建科学性高。

关键词：消毒供应中心卓越绩效德尔菲法质量评价指标体系

丹参转录因子SmWRKY1基因克隆及遗传转化拟南芥

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北方园艺 2024年第4期 81-89页

作者：凌娜杨朝霞杨雅兰刘炼邢硕铭孟凡荣商丘学院风景园林与建筑学院河南商丘476000 河南农业大学生命科学学院河南郑州450002

以丹参为试材,提取总RNA和合成cDNA,采用PCR扩增获得丹参转录因子SmWRKY1基因序列,通过生物信息软件及在线工具检测基因编码蛋白质的理化性质及氨基酸多序列比对,构建过表达载体并使用花序侵染法转入拟南芥,研究了转SmWRKY1基因对拟南... 详细信息

以丹参为试材,提取总RNA和合成cDNA,采用PCR扩增获得丹参转录因子SmWRKY1基因序列,通过生物信息软件及在线工具检测基因编码蛋白质的理化性质及氨基酸多序列比对,构建过表达载体并使用花序侵染法转入拟南芥,研究了转SmWRKY1基因对拟南芥生长性状和生理指标的影响,以期初步探究丹参SmWRKY1转录调控因子的生物学功能。结果表明:SmWRKY1基因全长1041 bp,编码346个氨基酸,NCBI数据库保守区BLAST分析显示具有典型的“WRKY”DNA结合保守结构域和C2H2型锌指结构。编码蛋白分子量为37310.4 Da,等电点pI为9.77,GRAVY为-0.571,ProtParam分析SmWRKY1属于亲水性蛋白。构建过表达载体pCAMBIA-SmWRKY1,并使用花序侵染法转入拟南芥,经鉴定获得11株转SmWRKY1基因的阳性苗,转基因植株可以使叶片和莲座直径显著变大,叶绿素和可溶性糖含量增加,MDA和脯氨酸含量减少,因此推测丹参SmWRKY1可能是一个与植物基础防御有关的负调控因子,参与植物非生物胁迫反应。

关键词：丹参 SmWRKY 基因克隆遗传转化

Optimization of ripple filter for pencil beam scanning

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Nuclear Science and Techniques 2013年第6期24卷 94-98页

作者： yang zhaoxia ZHANG Manzhou LI Deming Shanghai Institute of Applied Physics Chinese Academy of Sciences

This paper presents a novel approach to seek the bar width for ripple filter used in pencil beam scanning proton therapy.A weight decay quadratic programming method is employed for the new optimization *** to the commonly used iterative-least-square technique,the ripple filter derived by the proposed method not only has better depth dose uniformity,i.e.,the dose uniformity is within 0.5%,but also has triangle-like vertical cross-sectional shape which is suitable for ***,the new method has such good robust characteristics that it is also applicable to the real application with unavoidable measurement errors and *** simulation results of this study may be helpful in improving the design of the ripple filter.

关键词：优化策略滤波器扫描铅笔波纹最小二乘法二次规划截面形状

心脏磁共振自由呼吸运动校正人工智能电影序列在心力衰竭患者中的临床应用

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磁共振成像 2024年第3期15卷 62-67,73页

作者：冉玲平黄璐严祥虎赵赟杨朝霞周舒畅夏黎明华中科技大学同济医学院附属同济医院放射科武汉430030

目的通过评估自由呼吸运动校正人工智能(free-breathing with motion correction artificial intelligence,FB-MOCO AI)电影序列的图像质量、双心室容积和功能参数,探讨其在心力衰竭患者心脏磁共振(cardiac magnetic resonance,CMR)检查中应用的可行性。材料与方法前瞻性连续纳入2022年8月至2023年5月期间来我院进行CMR检查的心力衰竭患者29例。所有患者均行常规屏气电影和FB-MOCO AI电影序列的心脏短轴面扫描。由两名放射科医师对两种电影序列采集的图像进行整体图像质量评分(5分法)。测量两种序列的双心室容积和功能参数,包括舒张末期容积(end-diastolic volume,EDV)、收缩末期容积(end-systolic volume,ESV)、每搏输出量(stroke volume,SV)、射血分数(ejection fraction,EF)和左心室舒张末期质量(LV end-diastolic mass,LVEDM)。采用配对样本t检验或Wilcoxon符号秩检验来评估两种序列之间定量数据和定性评分数据的差异。并对两种序列间定量参数做相关性分析。通过Bland-Altman分析来评估从不同序列中获得的定量参数的一致性。结果FB-MOCO AI电影序列的总扫描时间[(14.3±1.9)s]比常规屏气电影[(79.2±11.4)s]明显缩短(P0.05),并且有强相关性(r值均≥0.94,P值均<0.001)。Bland-Altman分析显示,两种电影序列的所有心功能定量参数平均差异均接近于零,且变异范围很小,一致性高。结论与常规屏气电影序列相比,心衰患者中FB-MOCO AI电影序列扫描时间明显缩短并且提供了相当的图像质量、心室容积和功能指标,有潜力替代心衰患者的常规电影序列应用于临床。

关键词：心脏心力衰竭人工智能自由呼吸运动校正磁共振成像

Fluorescence Determination of Artemisinin Using Hemoglobin as Catalyst and Pyronine B as Substrate

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 704-708页

作者： CHEN Lihua ZHANG Yongkang YIN Hong LIU Liuzha yang zhaoxia SHEN Hanxi College of Chemistry and Chemical Engineering Jishou University Jishou 416000 Hunan China College of Chemistry Nankai University Tianjin 300071China

Fluorescence decrease ratio was applied to determine of arte misinin （qinghaosu, QHS） based on the catalytic effect of hemoglobin （Hb） using tetraethyldiaminoxanthenyl chloride （Pryonine B, PB） as monitor in this work, Experimental results show that the catalytic characteristics of Hb for QHS, being expressed as Michaelis-Menten parameters, Km, Vmax and Kcat are 2.8×10^-5 mol·L^-1, 4.2×10^-5 mol·L^-1·s^-1 and 280 s^-1 , respectively. Like hemin, enzymatic bioactivities of Hb is inhibited by both deactivated agents and high temperature whereas enhanced by ethanol. With the catalytic action of Hb, quantitative method of QHS can be established based on the fluorescence decrease of PB and linear relationship between the fluorescence decrease ratio F0/F and the concentration of QHS is in the range of （0.0-1.1）×10^-6 mol·L^-1 with detection limit （3σ） being 7. 2×10^-9 mol·L^-1, The concentration of QHS in the media of plasma or urine was detected using this method.

关键词： hemoglobin artemisinin pyronine B fluorescence decrease ratio

Cyber-Physical Resilience Enhancement for Power Transmission Systems with Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 844-855页

作者： Wenhao Zhang Dongyang Rui Weihong Wang yang Guo zhaoxia Jing Wenhu Tang School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China Guangzhou Zhiguang Electric Co. Ltd and Zhiguang Research Institute(Guangzhou)Co.LtdGuangzhou 510765China

In a power system, when extreme events occur, such as ice storm, large scale blackouts may be unavoidable. Such small probability but high risk events have huge impact on power systems. Most resilience research in power systems only considers faults on the physical side, which would lead to overly idealistic results. This paper proposes a two-stage cyber-physical resilience enhancement method considering energy storage (ES) systems. The first stage calculates optimal planning of ES systems, and the second stage assesses resilience and enhancement of ES systems during the disaster. In the proposed model, cyber faults indirectly damage the system by disabling monitoring and control function of control center. As a result, when detection and response process of physical faults are blocked by cyber failures, serious load shedding occurs. Such a cyber-physical coupling mechanism of fault, response, restoration process is demonstrated in the modified IEEE Reliable Test System-79 (RTS-79). Simulation results show compared with the physical-only system, the cyber-physical system has a more accurate but degraded resilient performance. Besides, ES systems setting at proper place effectively enhance resilience of the cyber-physical transmission system with less load Shedding.

关键词： Cyber-physical faults energy storage systems resilience enhancement transmission systems

THE STUDENT-CENTRED CLASS

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Chinese Journal of Applied Linguistics 1996年第1期19卷 39-41页

作者： yang zhaoxia

IntroductionIn recent years,many theories have been put forward on second language teaching,and the focus ofattention has shifted from the teacher,who has tended to be the centre of the classroom,to thelearners,whose role is‘to react to the stimuli and instructions’(Littlewood,1990:1)provided by *** and practical research have resulted in a new methodology-the student-centredclass.

关键词：初记