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A new model for dissipative particle dynamics boundary condition of walls with different wettabilities

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Applied Mathematics and Mechanics(English Edition) 2021年第4期42卷 467-484页

作者： yuyi wang Jiangwei SHE Zhewei ZHOU Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China

The implementation of solid-fluid boundary condition has been a major challenge for dissipative particle dynamics(DPD)*** implementations of boundary conditions usually try to approach a uniform density distribution and a velocity profile close to analytical *** density oscillations and slip velocity are intentionally eliminated,and different wall properties disappear in the same analytical *** paper develops a new wall model that combines image and frozen particles and a new strategy to emphasize different wall properties especially *** strategy first studies the realistic wall-fluid system by molecular dynamics(MD)simulation depending on physical ***,a DPD simulation is used to match the density and velocity profiles with the new wall *** obtained DPD parameters can simulate the systems with the same wall and fluid *** this method,a simulation of the Poiseuille flow of liquid argon with copper walls is *** walls with super-hydrophilic,hydrophilic,and hydrophobic wettabilities are also *** limitations of the analytical solution and the effect of the wall-fluid interaction are *** results show that the method suggested in this paper can simulate the mesoscale behavior of the microchannel flow related to realistic systems.

关键词： dissipative particle dynamics(DPD) molecular dynamics(MD) wall-fluid interaction image particle wettability

基于患者队列的随机对照试验设计:队列内试验(TwiCs)的方法与应用

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中国实验方剂学杂志 2024年第5期30卷 96-102页

作者：王禹毅施泽阳李恪丞卜志军王雪惠王彬刘建平刘兆兰北京中医药大学循证医学中心北京100029 重庆市中医院重庆400011 北京中医药大学东直门医院北京101121

队列内试验(TwiCs)是随机对照试验的一种衍生设计方法,目前已在肿瘤、心血管疾病等慢性疾病领域内广泛应用。TwiCs设计基础是一个特定疾病的前瞻性队列,当要实施随机对照试验时,从队列中随机抽样部分符合纳入排除标准的患者接受“试验... 详细信息

队列内试验(TwiCs)是随机对照试验的一种衍生设计方法,目前已在肿瘤、心血管疾病等慢性疾病领域内广泛应用。TwiCs设计基础是一个特定疾病的前瞻性队列,当要实施随机对照试验时,从队列中随机抽样部分符合纳入排除标准的患者接受“试验干预”,而队列中符合纳入排除标准但未被抽样的患者继续接受常规治疗并作为对照组。通过比较试验组和对照组干预措施的疗效差异,来评估干预措施的效果。在队列内,可以重复执行同样的过程来实施多个随机对照试验(RCTS),以评估不同干预措施或比较不同剂量或时机的干预效果。相较经典随机对照试验,TwiCs利用队列更易招募患者,具有更高的外部真实性,为提升随机对照试验的效率和适用性提供了临床研究新范式。但同时TwiCs也可能面临队列内患者依从性不高的挑战,需要研究者在TwiCs设计和操作过程中采取有效措施进行控制。该文重点介绍了TwiCs实施过程中的方法学要点,包括多阶段知情同意(患者进入队列、进入试验组、试验结束后3个阶段分别进行知情同意)、随机程序(只从队列中随机抽样接受“试验干预”的患者)、样本量计算、统计分析方法,对比了TwiCs与经典RCTS的差异,并以实例说明TwiCs研究设计与分析的过程,以期为广大临床研究者提供新的研究思路和方法。

关键词：队列内试验队列多重随机对照试验患者队列随机抽样多阶段知情同意

A modified rheological model of natural debris flows

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Chinese Science Bulletin 2000年第8期45卷 743-748页

作者： wang yuyi FEI Xiangjun CHEN Rui Chengdu Institute of Mountain Hazards and Environment Chinese Academy of SciencesDongchuan Debris Flow Observation and Research StationChinese Academy of SciencesChengdu 610041China Department of Hydraulics Qinghua UniversityBeijing 100083China

The two coefficients of the linear dimensionless viscous-dispersive mixture model have been modified according to their rheological properties of different types of viscous debris flows based on the observation and experimental data of debris flows and their slurries in the field, and then a rheological model of hyperconcentrated debris flows has been derived. The modified coefficients are the exponent of A which is modified by the highly-viscous slurry medium, and the maximum density which is modified by the volume concentration of original debris flows with heterogenous grain size.

关键词： debris flow Theological properties rheological model.

Quantum speedup of twin support vector machines

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Science China(Information Sciences) 2020年第8期63卷 272-274页

作者： Zekun YE Lvzhou LI Haozhen SITU yuyi wang School of Data and Computer Science Sun Yat-Sen University Ministry of Education Key Laboratory of Machine Intelligence and Advanced Computing (Sun Yat-Sen University) College of Mathematics and Informatics South China Agricultural University

Dear editor,Machine learning enables agents or computers to learn from data and improves the performance of specific tasks without requiring explicit programming. As the amount of available data continues to grow, existing machine learning algorithms cannot satisfy the efficiency requirements of various practical applications, and several methods have been

关键词： quantum computing quantum machine learning quantum algorithms twin support vector machines exponential speedup

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防风药材质量的多指标综合评价

浙江农林大学学报 2024年第4期41卷 715-723页

作者：马丙如崔静轩王雨懿刘子君宁凝王云贺杨利民韩忠明吉林农业大学中药材学院/吉林省生态系统与生态恢复重点实验室吉林长春130118 白山市食品药品检验所吉林长春134300 吉林吉隆东北沙棘产业有限责任公司吉林大安131300 国药集团北京华邈药业有限公司北京102600

【目的】建立防风Saposhnikovia divaricata药材多指标成分同时定量分析的测定方法,并以多指标成分为评价指标,结合不同成分对防风药材抗炎活性的贡献,分析不同产地的防风药材质量,为防风药材质量的综合评价提供科学依据。【方法】采用... 详细信息

【目的】建立防风Saposhnikovia divaricata药材多指标成分同时定量分析的测定方法,并以多指标成分为评价指标,结合不同成分对防风药材抗炎活性的贡献,分析不同产地的防风药材质量,为防风药材质量的综合评价提供科学依据。【方法】采用高效液相色谱(HPLC)建立防风6种色原酮和4种香豆素成分同时定量的测定方法,采用聚类分析和主成分分析对防风药材质量进行综合评价;采用脂多糖诱导的RAW 264.7小鼠巨噬细胞炎症模型,分析防风10种化学成分与抗炎活性的相关关系。【结果】防风10种化学成分在各自范围内线性关系、准确度和分离度均良好。聚类分析和主成分分析把17批样品分为4类,其中以内蒙古S5和吉林S8~S11产地的2年生防风的综合质量相对较好;17批防风醇提物能不同程度地抑制脂多糖诱导的RAW264.7细胞分泌一氧化氮(NO)、白细胞介素6(IL-6)、白细胞介素1β(IL-1β);其中升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷、5-O-甲基维斯阿米醇、欧前胡素与抗炎活性呈正相关;灰色关联度分析表明:防风抗炎活性是多种成分协同作用的结果,升麻素苷、5-O-甲基维斯阿米醇苷、升麻素、亥茅酚苷、5-O-甲基维斯阿米醇与3个细胞炎症指标(NO、IL-6和IL-1β)的关联度均大于0.8,是发挥抗炎作用的主要物质基础。【结论】本研究建立的防风多指标成分测定方法良好,可用于防风色原酮和香豆素成分的同时测定,结合抗炎活性与灰色关联度分析法建立了基于生物活性的防风药材质量综合评价模式,为建立防风药材质量综合评价的标准提供了新的方法和科学依据。

关键词：防风色原酮香豆素抗炎活性关联度分析

Gravel Accumulation in Deposits of Viscous Debris Flows with Hyper-concentration

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Journal of Mountain Science 2009年第1期6卷 88-95页

作者： wang yuyi TAN Rongzhi JAN Chyandeng TIAN Bing Key Laboratory of Mountain Hazards & Earth Surface Process Chinese Academy of Sciences Institute of Mountain Hazards & Environment Chinese Academy of Sciences Chengdu 610041 China Department of Hydraulics & Ocean Engineering ChengKung University Tainan Taiwan 70101 China College of Resources & Environment Science Hebei Normal University Shijiazhuang 050016 China

According to the observational data of viscous debris flows with hyper-concentration, debris flows can be classified into three types:high-viscous, viscous, and sub-viscous debris *** formation mechanism of different graded bedding structures in deposits of viscous debris flows was analyzed in this paper by using their yield-stress ratio and flow plug *** paper specially analyzed the effect of Weissenberg which the gravels in squirm condition of hyper-concentration viscous flows would tend to move vertically, and the formation mechanism of the gravels accumulated at surface was also *** analysis in this paper can establish a foundation for the studies on differentiation of bedding structures of debris flow deposits and studies on dynamic parameters of debris flows.

关键词： Viscous debris flow effective yield-stressratio flow plug ratio effect of Weissenberg gravelaccumulation at surface

Close Relationship between the Frangibility of Mountain Eco-Environment and Mountain Disasters:A Case Study of Dongchuan,Kunming in Yunnan Province

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Wuhan University Journal of Natural Sciences 2007年第4期12卷 721-728页

作者： wang yuyi TIAN Bing LIU Shuzhen Key Laboratory of Mountain Hazards and Surface Process Chinese Academy of Sciences/Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China Graduated University of Chinese Academy of Sciences Beijing 100049 China College of Resources and Environment Science Hebei Normal University Shijiazhuang 050061 Hebei China

Anatomical details are given in this article, which is performed by investigating the relationship between through the frangibility of mountain eco-environment and the status of irrational land-use in typical region of debris flow in Dongchuan district, Kunming city, yunnan Province. This analysis is extended to the relationship between vicissitude of mountain disasters and the frangibility of mountain environment. The relatively coupling action of a vicious circle is a evolving characteristic by debris flow sand-gravel there. The eco-security is being faced with serious challenge. The tactics of eco-security has been constructed since 1980s. Thus, the eco-environrnent can gradually be repaired and optimized to achieve a fine circle.

关键词： eco-environment frangibility mountain disasters eco-security

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盲法质量评价方法在中医临床试验中的应用

中国实验方剂学杂志 2024年第3期30卷 75-80页

作者：施泽阳孙源马文欣王禹毅卜志军王雪惠郑酉友刘建平刘兆兰北京中医药大学循证医学中心北京100029 烟台市疾病预防控制中心山东烟台264003 重庆市中医院重庆400017 中国中医科学院中医药信息研究所北京100700

盲法质量评价是对实施盲法的临床试验所获得的临床盲化数据进行评估,通过调查分析不同设盲对象的致盲效果来判断盲法实施的有效性。成功的盲法能够在一定程度上避免受试对象和研究者由于主观因素对试验结果造成的影响,而通过盲法质量评... 详细信息

盲法质量评价是对实施盲法的临床试验所获得的临床盲化数据进行评估,通过调查分析不同设盲对象的致盲效果来判断盲法实施的有效性。成功的盲法能够在一定程度上避免受试对象和研究者由于主观因素对试验结果造成的影响,而通过盲法质量评价不仅可以反映盲法实施的有效性,更能体现临床试验结果的准确性和可信度。近年来随机对照试验广泛应用于中医药临床疗效评价,但其盲法的实施质量参差不齐,尚未形成评价标准。该文对两种定量盲法质量评价方法——James盲法指数(JBI)和Bang盲法指数(BBI)的数据收集方式、计算原理和优缺点进行介绍,并在一项针灸缓解口腔术后疼痛的随机对照试验中进行2种指数的实例分析,应用R软件演示结果计算过程并通过森林图进行可视化展示,同时设计了便于在试验不同阶段进行中医药临床试验盲法评价资料收集的工具表,最后对盲法质量评价在中医药研究中的必要性和可行性进行探讨,以期为评价和提高中医药临床试验中盲法实施质量提供依据。

关键词：盲法质量评价临床试验中医方法学

Experimental Study on the Viscoelastic Behaviors of Debris Flow Slurry

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Journal of Mountain Science 2012年第4期9卷 501-510页

作者： wang yuyi TAN Rongzhi HU Kaiheng CHEN Feiyue YANG Hongjuan ZHANGJinshan LV Juan Key Laboratory of Mountain Hazards and Earth Surface Process Dongchuan Debris Flow Observation and Research Station Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Shanghai Representative Office Anton Paar GmbH Shanghai 200040 China

The rheological properties of most liquid in nature are between liquids and solids, including both elastic changes and viscosity changes, that is socalled ＂viscoelastic＂. Dynamic oscillatory test was used to quantitatively study the distinct viscoelastic behaviors of debris flow slurry in the shear stress conditions for the first time in this study. The debris flow slurry samples were from Jiangjiagou Ravine, Yunnan Province, China. The experimental results were found that at the low and middle stages of shearing, when the angular velocity 09〈72.46 s-1, the loss modulus （G was greater than the storage modulus （G3, i.e. G＂〉G＇. At the late stage of shearing, when the angular velocity co-72.46 s-x, the storage modulus was greater than or equal to the loss G = G, tan -〈 1 （where phase-shift modulus, i.e. ＇〉＂ angle 5=G＂,/G3, and the debris flow slurry was in a gel state. Therefore, the progress of this experimental study further reveals the mechanism of hyperconcentrated debris flows with a high velocity on low-gradient ravines.

关键词： Loss modulus (G" Storage modulus (G' Viscoelastic behaviors Gel state