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Can baseline ML Flow test results predict leprosy reactions? An investigation in a cohort of patients enrolled in the uniform multidrug therapy clinical trial for leprosy patients in Brazil 被引量:2
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作者 Emerith Mayra Hungria Regiane Morillas Oliveira +8 位作者 Gerson Oliveira Penna Lúcio Cartaxo Aderaldo Maria Araci de Andrade Pontes Rossilene Cruz Heitor de SáGonçalves Maria Lúcia Fernandes Penna Ligia Regina Franco Sansigolo Kerr Mariane Martins de Araújo Stefani Samira Bührer-Sékula 《Infectious Diseases of Poverty》 SCIE 2016年第1期1012-1021,共10页
Background:The predictive value of the serology to detection of IgM against the Mycobacterium leprae-derived phenolic glycolipid-I/PGL-I to identify leprosy patients who are at higher risk of developing reactions rema... Background:The predictive value of the serology to detection of IgM against the Mycobacterium leprae-derived phenolic glycolipid-I/PGL-I to identify leprosy patients who are at higher risk of developing reactions remains controversial.Whether baseline results of the ML Flow test can predict leprosy reactions was investigated among a cohort of patients enrolled in The Clinical Trial for Uniform Multidrug Therapy for Leprosy Patients in Brazil(U-MDT/CT-BR).Methods:This was a descriptive study focusing on the main clinical manifestations of leprosy patients enrolled in the U-MDT/CT-BR from March 2007 to February 2012 at two Brazilian leprosy reference centers.For research purposes,753 leprosy patients were categorized according to a modified Ridley-Jopling(R&J)classification and according to the development of leprosy reactions(reversal reaction/RR and erythema nodosum leprosum/ENL),and whether they had a positive or negative bacillary index/BI.Results:More than half of the patients(55.5%)reported leprosy reaction:18.3%(138/753)had a RR and 5.4%(41/753)had ENL.Leprosy reactions were more frequent in the first year following diagnosis,as seen in 27%(205/753)of patients,while 19%(142/753)developed reactions during subsequent follow-up.Similar frequencies of leprosy reactions and other clinical manifestations were observed in paucibacillary(PB)and multibacillary(MB)leprosy patients treated with U-MDT and regular MDT(R-MDT)(P=0.43 and P=0.61,respectively).Compared with PB patients,leprosy reactions were significantly more frequent in MB patients with a high BI,and more patients developed RR than ENL.However,RR and neuritis were also reported in patients with a negative BI.At baseline,the highest rate of ML Flow positivity was observed in patients with a positive BI,especially those who developed ENL,followed by patients who had neuritis and RR.Among reaction-free patients,81.9%were ML Flow positive,however,the differences were not statistically significant compared to reactional patients(P=0.45).Conclusions:MB and PB patients treated with R-MDT and U-MDT showed similar frequencies of RR and other clinical manifestations.Positive ML Flow tests were associated with MB leprosy and BI positivity.However,ML Flow test results at baseline showed limited sensitivity and specificity for predicting the development of leprosy reactions. 展开更多
关键词 LEPROSY Leprosy reactions Bacillary index Phenolic glycolipid-I Clinical trial ML flow test U-MDT/CT-BR Brazil
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Impact of Typical Steady-state Conditions and Transient Conditions on Flow Ripple and Its Test Accuracy for Axial Piston Pump 被引量:14
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作者 XU Bing HU Min ZHANG Junhui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期1012-1022,共11页
The current research about the flow ripple of axial piston pump mainly focuses on the effect of the structure of parts on the flow ripple. Therein, the structure of parts are usually designed and optimized at rated wo... The current research about the flow ripple of axial piston pump mainly focuses on the effect of the structure of parts on the flow ripple. Therein, the structure of parts are usually designed and optimized at rated working conditions. However, the pump usually has to work in large-scale and time-variant working conditions. Therefore, the flow ripple characteristics of pump and analysis for its test accuracy with respect to variant steady-state conditions and transient conditions in a wide range of operating parameters are focused in this paper. First, a simulation model has been constructed, which takes the kinematics of oil film within friction pairs into account for higher accuracy. Afterwards, a test bed which adopts Secondary Source Method is built to verify the model. The simulation and tests results show that the angular position of the piston, corresponding to the position where the peak flow ripple is produced, varies with the different pressure. The pulsating amplitude and pulsation rate of flow ripple increase with the rise of pressure and the variation rate of pressure. For the pump working at a constant speed, the flow pulsation rate decreases dramatically with the increasing speed when the speed is less than 27.78% of the maximum speed, subsequently presents a small decrease tendency with the speed further increasing. With the rise of the variation rate of speed, the pulsating amplitude and pulsation rate of flow ripple increase. As the swash plate angle augments, the pulsating amplitude of flow ripple increases, nevertheless the flow pulsation rate decreases. In contrast with the effect of the variation of pressure, the test accuracy of flow ripple is more sensitive to the variation of speed. It makes the test accuracy above 96.20% available for the pulsating amplitude of pressure deviating within a range of ~6% from the mean pressure. However, with a variation of speed deviating within a range of ±2% from the mean speed, the attainable test accuracy of flow ripple is above 93.07%. The model constructed in this research proposes a method to determine the flow ripple characteristics of pump and its attainable test accuracy under the large-scale and time-variant working conditions. Meanwhile, a discussion about the variation of flow ripple and its obtainable test accuracy with the conditions of the pump working in wide operating ranges is given as well. 展开更多
关键词 axial piston pump flow ripple test accuracy steady-state condition transient condition wide operating ranges
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Development of an Improved GUI Automation Test System Based on Event-Flow Graph 被引量:2
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作者 Yongzhong Lu Danping Yan +1 位作者 Songlin Nie Chun Wang 《Journal of Software Engineering and Applications》 2008年第1期38-43,共6页
A more automated graphic user interface (GUI) test model, which is based on the event-flow graph, is proposed. In the model, a user interface automation API tool is first used to carry out reverse engineering for a GU... A more automated graphic user interface (GUI) test model, which is based on the event-flow graph, is proposed. In the model, a user interface automation API tool is first used to carry out reverse engineering for a GUI test sample so as to obtain the event-flow graph. Then two approaches are adopted to create GUI test sample cases. That is to say, an improved ant colony optimization (ACO) algorithm is employed to establish a sequence of testing cases in the course of the daily smoke test. The sequence goes through all object event points in the event-flow graph. On the other hand, the spanning tree obtained by deep breadth-first search (BFS) approach is utilized to obtain the testing cases from goal point to outset point in the course of the deep regression test. Finally, these cases are applied to test the new GUI. Moreover, according to the above-mentioned model, a corresponding prototype system based on Microsoft UI automation framework is developed, thus giving a more effective way to improve the GUI automation test in Windows OS. 展开更多
关键词 Automated Software testING GRAPHIC User Interface Event-flow Graph Regression testING ANT COLONY Optimization UI AUTOMATION
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Design and Implementation of Test Flow Description Language
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作者 孟晨 王成 杨锁昌 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第2期158-160,共3页
A test flow description language is designed for the description of test flow.The design concept,composition,program structure and syntax structure of statement are presented.The development and impletementation proce... A test flow description language is designed for the description of test flow.The design concept,composition,program structure and syntax structure of statement are presented.The development and impletementation processes of the language are also described.This language is independent of hardware,which can be used for different platforms,and can be extended.The language is used to describe the test flow easily.It simplifies the development process of test software and reduces the difficulty of software maintenance greatly. 展开更多
关键词 描述语言 测试流程 设计概念 语法结构 程序结构 测试软件 开发过程 软件维护
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3D Particle Image Velocimetry Test of Inner Flow in a Double Blade Pump Impeller 被引量:5
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作者 LIU Houlin WANG Kai +3 位作者 YUAN Shouqi TAN Minggao WANG Yong RU Weimin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期491-497,共7页
The double blade pump is widely used in sewage treatment industry,however,the research on the internal flow characteristics of the double blade pump with particle image velocimetry(PIV) technology is very little at ... The double blade pump is widely used in sewage treatment industry,however,the research on the internal flow characteristics of the double blade pump with particle image velocimetry(PIV) technology is very little at present.To reveal inner flow characteristics in double blade pump impeller under off-design and design conditions,inner flows in a double blade pump impeller,whose specific speed is 111,are measured under the five off-design conditions and design condition by using 3D PIV test technology.In order to ensure the accuracy of the 3D PIV test,the external trigger synchronization system which makes use of fiber optic and equivalent calibration method are applied.The 3D PIV relative velocity synthesis procedure is compiled by using Visual C++ 2005.Then absolute velocity distribution and relative velocity distribution in the double blade pump impeller are obtained.Test results show that vortex exists in each condition,but the location,size and velocity of vortex core are different.Average absolute velocity value of impeller outlet increases at first,then decreases,and then increases again with increase of flow rate.Again average relative velocity values under 0.4,0.8,and 1.2 design condition are higher than that under 1.0 design condition,while under 0.6 and 1.4 design condition it is lower.Under low flow rate conditions,radial vectors of absolute velocities at impeller outlet and blade inlet near the pump shaft decrease with increase of flow rate,while that of relative velocities at the suction side near the pump shaft decreases.Radial vectors of absolute velocities and relative velocities change slightly under the two large flow rate conditions.The research results can be applied to instruct the hydraulic optimization design of double blade pumps. 展开更多
关键词 double blade pump IMPELLER inner flow 3D particle image velocimetry(PIV) test
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基于FLOW⁃3D数值模拟和物理模型试验的水闸水流条件研究
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作者 刘德宇 武帅 +1 位作者 曹阳 李桂青 《水利水电工程设计》 2024年第2期63-68,共6页
介绍FLOW-3D数值模拟和物理模型试验在海口市龙塘大坝枢纽改造工程水流条件研究的应用,通过各工况的数值模拟与物理模型试验,对水闸水流流态、流速和沿程水面线等水力特性进行计算与观测。经对比分析,各工况下FLOW-3D数值模拟和物理模... 介绍FLOW-3D数值模拟和物理模型试验在海口市龙塘大坝枢纽改造工程水流条件研究的应用,通过各工况的数值模拟与物理模型试验,对水闸水流流态、流速和沿程水面线等水力特性进行计算与观测。经对比分析,各工况下FLOW-3D数值模拟和物理模型试验所得的流态、水面线、流速变化及分布规律基本一致,为研究泄水建筑物布置及体型设计的可行性及合理性,泄水建筑物设计及运行管理提供了科学依据。 展开更多
关键词 flow-3D 数值模拟 物理模型试验 水流条件
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Centrifuge model tests of the formation mechanism of coarse sand debris flow
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作者 周建 周韵鸿 +1 位作者 LI Ye-xun WANG Zi-han 《Journal of Chongqing University》 CAS 2014年第3期77-89,共13页
Using the self-developed visualization test apparatus, centrifuge model tests at 20 g were carried out to research the macro and microscopic formation mechanism of coarse sand debris flows. The formation mode and soil... Using the self-developed visualization test apparatus, centrifuge model tests at 20 g were carried out to research the macro and microscopic formation mechanism of coarse sand debris flows. The formation mode and soil-water interaction mechanism of the debris flows were analyzed from both macroscopic and microscopic points of view respectively using high digital imaging equipment and micro-structure analysis software Geodip. The test results indicate that the forming process of debris flow mainly consists of three stages, namely the infiltration and softening stage, the overall slide stage, and debris flow stage. The essence of simulated coarse sand slope forming debris flow is that local fluidization cause slope to wholly slide. The movement of small particles forms a transient stagnant layer with increasing saturation, causing soil shear strength lost and local fluidization. When the driving force of the saturated soil exceeds the resisting force, debris flow happens on the coarse sand slope immediately. 展开更多
关键词 coarse SAND DEBRIS flow CENTRIFUGE model tests formation mode water-soil interaction mechanism
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Sand deposit-detecting method and its application in model test of sand flow 被引量:2
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作者 黎伟 房营光 +2 位作者 莫海鸿 谷任国 陈俊生 《Journal of Central South University》 SCIE EI CAS 2013年第10期2840-2848,共9页
Against the background of the sand-flow foundation treatment engineering of Guangzhou Zhoutouzui variable cross-section immersed tunnel, a kind of sand deposit-detecting method was devised on the basis of full-scale m... Against the background of the sand-flow foundation treatment engineering of Guangzhou Zhoutouzui variable cross-section immersed tunnel, a kind of sand deposit-detecting method was devised on the basis of full-scale model test of sand-flow method. The real-time data of sand-deposit height and radius were obtained by the self-developed sand-deposit detectors. The test results show that the detecting method is simple and has high precision. In the use of sand-flow method, the sand-carrying capability of fluid is limited, and sand particles are all transported to the sand-deposit periphery through crater, gap and chutes after the sand deposit formed. The diffusion range of the particles outside the sand-deposit does not exceed 2.0 m. Severe sorting of sand particles is not observed because of the unique oblique-layered depositing process. The temporal and spatial distributions of gap and chutes directly affect the sand-deposit expansion, and the expansion trend of the average sand-deposit radius accords with quadratic time-history curve. 展开更多
关键词 immersed tube TUNNEL FOUNDATION treatment model test of sand-flow method SAND DEPOSIT detecting structural characteristics of sand-deposit
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基于SolidWorks Flow Simulation的PCB测试设备机柜散热仿真分析
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作者 张世光 赵文燕 邹振霖 《机电工程技术》 2024年第5期54-57,共4页
为了解决PCB测试设备在机柜中温度过高导致被测产品损坏的问题。根据实际应用场景,设计出一款具有散热高效、结构紧凑、制作成本低的PCB测试设备机柜。结合PCB检测设备整体结构对其所在的机柜进行结构设计和散热仿真分析。主要以4台PCB... 为了解决PCB测试设备在机柜中温度过高导致被测产品损坏的问题。根据实际应用场景,设计出一款具有散热高效、结构紧凑、制作成本低的PCB测试设备机柜。结合PCB检测设备整体结构对其所在的机柜进行结构设计和散热仿真分析。主要以4台PCB测试设备满载运行在机柜中散热情况为研究对象。根据实际结构,使用SolidWorks对机柜和测试设备简化仿真模型进行建模,将简化模型导入到SolidWorks Flow Simulation中对机柜进行散热仿真分析。通过分析计算得出散热的分布情况和测试设备关键地方的温升数值,判断机柜散热结构的散热情况是否与预期结果一致。试验结果表明:常温下,在机柜中4台PCB测试设备满载测试时检测区域最高温度达到28℃左右,能够可持续运行状态并保持稳定工作。通过试验验证,机柜的散热实际温度与其散热仿真结果相符,证实了该机柜散热结构设计的合理性以及正确性,并且确定机柜散热结构设计方案。 展开更多
关键词 PCB测试设备 机柜 散热仿真分析 SolidWorks flow Simulation
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基于Moldflow的储物盒注塑成型模拟及试验验证 被引量:10
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作者 黄可 许成中 +2 位作者 刘江 马雪峰 卜凡 《工程塑料应用》 CAS CSCD 北大核心 2019年第8期86-90,共5页
对储物盒盖的注塑难点进行分析,得出模具应设计成单热流道双腔结构。选取熔体温度、注射时间、保压压力、保压时间为研究对象,利用Moldflow 2018模流分析软件,构建4因素4水平正交试验,通过极差分析,得出储物盒盖在熔体温度226℃、注射时... 对储物盒盖的注塑难点进行分析,得出模具应设计成单热流道双腔结构。选取熔体温度、注射时间、保压压力、保压时间为研究对象,利用Moldflow 2018模流分析软件,构建4因素4水平正交试验,通过极差分析,得出储物盒盖在熔体温度226℃、注射时间14 s、保压压力70 MPa、保压时间10 s的条件下,变形总量最小,为0.45 mm。对获得的最优参数进行了试验验证,验证结果表明,成型后储物盒盖整体外观良好;佐证了Moldflow 2018有限元分析数据准确,正交试验构建及模具设计合理。 展开更多
关键词 熔体温度 注射时间 保压压力 保压时间 模流分析 正交试验
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Nonlinear fluid flow through three-dimensional rough fracture networks:Insights from 3D-printing,CT-scanning,and high-resolution numerical simulations 被引量:1
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作者 Bo Li Jiafei Wang +1 位作者 Richeng Liu Yujing Jiang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第5期1020-1032,共13页
Nonlinear flow behavior of fluids through three-dimensional(3D)discrete fracture networks(DFNs)considering effects of fracture number,surface roughness and fracture aperture was experimentally and numerically investig... Nonlinear flow behavior of fluids through three-dimensional(3D)discrete fracture networks(DFNs)considering effects of fracture number,surface roughness and fracture aperture was experimentally and numerically investigated.Three physical models of DFNs were 3D-printed and then computed tomography(CT)-scanned to obtain the specific geometry of fractures.The validity of numerically simulating the fluid flow through DFNs was verified via comparison with flow tests on the 3D-printed models.A parametric study was then implemented to establish quantitative relations between the coefficients/parameters in Forchheimer’s law and geometrical parameters.The results showed that the 3D-printing technique can well reproduce the geometry of single fractures with less precision when preparing complex fracture networks,numerical modeling precision of which can be improved via CT-scanning as evidenced by the well fitted results between fluid flow tests and numerical simulations using CT-scanned digital models.Streamlines in DFNs become increasingly tortuous as the fracture number and roughness increase,resulting in stronger inertial effects and greater curvatures of hydraulic pressure-low rate relations,which can be well characterized by the Forchheimer’s law.The critical hydraulic gradient for the onset of nonlinear flow decreases with the increasing aperture,fracture number and roughness,following a power function.The increases in fracture aperture and number provide more paths for fluid flow,increasing both the viscous and inertial permeabilities.The value of the inertial permeability is approximately four orders of magnitude greater than the viscous permeability,following a power function with an exponent a of 3,and a proportional coefficient b mathematically correlated with the geometrical parameters. 展开更多
关键词 Nonlinear flow 3D-printing CT-scanning Fracture network Permeability Fluid flow test
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基于Visual Modflow的岩溶水疏降流场模拟和涌水量预测 被引量:16
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作者 刘永良 潘国营 《河南理工大学学报(自然科学版)》 CAS 2009年第1期51-54,共4页
为确保鹤壁矿区寺湾矿安全生产,采用国际通用的Visual Modflow地下水渗流模拟软件,以寺湾矿石炭系太原组二灰岩溶水大型放水试验为基础,建立了岩溶水三维渗流数值模型.通过该模型的识别和检验,成功模拟了放水试验所形成的渗流场和水位... 为确保鹤壁矿区寺湾矿安全生产,采用国际通用的Visual Modflow地下水渗流模拟软件,以寺湾矿石炭系太原组二灰岩溶水大型放水试验为基础,建立了岩溶水三维渗流数值模型.通过该模型的识别和检验,成功模拟了放水试验所形成的渗流场和水位动态变化,利用此模型计算的设计疏降水平的涌水量与采用相关曲线外推法、漏斗均衡法和解析法计算结果相差不大,已成为矿井排水系统改造的重要参数,为受承压水威胁的太原组下夹煤的安全合理开采提供了科学依据. 展开更多
关键词 Visual MODflow 放水试验 疏降流场 矿井涌水量
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基于Moldflow的PP薄壁制品注塑工艺计算机模拟 被引量:15
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作者 磨莉 谷林 《工程塑料应用》 CAS CSCD 北大核心 2016年第4期69-73,共5页
利用Moldfl ow对Taguchi法和L16(45)正交表所设计出的聚丙烯(PP)薄壁制品注塑方案进行仿真,研究发现:注射时间、保压时间、保压压力是影响PP薄壁制品翘曲变形的主要因素,并且得到最优注塑参数为:注塑机料筒温度180℃,模具温度75℃,注射... 利用Moldfl ow对Taguchi法和L16(45)正交表所设计出的聚丙烯(PP)薄壁制品注塑方案进行仿真,研究发现:注射时间、保压时间、保压压力是影响PP薄壁制品翘曲变形的主要因素,并且得到最优注塑参数为:注塑机料筒温度180℃,模具温度75℃,注射时间3.0 s,保压时间3.5 s,保压压力65 MPa。另外,通过CAE模流分析软件中PP薄壁制品注塑加工的翘曲变形进行仿真发现,正交试验所获得的优化工艺的总翘曲变形量为1.417 mm,翘曲变形百分比约为3.30%。其中由于冷却引起的翘曲变形量约为0.159 mm,而由收缩和取向引起的翘曲变形分别约为1.853 mm和0.904 mm。 展开更多
关键词 翘曲变形 MOLDflow 正交试验法 CAE模流分析 计算机仿真
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OpenFlow交换机协议一致性测试集模型研究
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作者 曾帅 殷志坚 《电信网技术》 2016年第5期67-69,共3页
针对当前的Open Flow交换机协议测试技术的研究现状,介绍了两个Open Flow交换机协议一致性测试的测试集模型。
关键词 OPEN flow交换机 一致性测试 测试集
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基于Flow Simulation的物料悬浮速度测试装置的流体分析 被引量:1
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作者 连萌 《黄河水利职业技术学院学报》 2018年第2期41-45,共5页
为了优化物料悬浮速度测试套筒的结构,应用Flow simulation软件对测试套筒内的气流速度分布情况和不同风量开度对气流速度的影响进行了分析。结果表明,套筒内的气流速度随着锥筒高度的增加而呈线性下降;锥筒高度相同时,越靠近锥筒轴线,... 为了优化物料悬浮速度测试套筒的结构,应用Flow simulation软件对测试套筒内的气流速度分布情况和不同风量开度对气流速度的影响进行了分析。结果表明,套筒内的气流速度随着锥筒高度的增加而呈线性下降;锥筒高度相同时,越靠近锥筒轴线,气流速度越高;在锥筒中下部半径为0.2 m范围内,气流速度变化一致性好,有利于悬浮速度的测量;风量开度与锥筒下断口处的气流速度近似为线性关系,通过调节风量开度能够有效调节锥筒内的气流速度。 展开更多
关键词 气力技术 物料悬浮速度 测试套筒 flowsimulation软件 流体分析 气流速度 风量开度
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Characteristics of non-Darcy flow in low-permeability reservoirs 被引量:17
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作者 Yao Yuedong Ge Jiali 《Petroleum Science》 SCIE CAS CSCD 2011年第1期55-62,共8页
Well testing is recognized as an effective means of accurately obtaining the formation parameters of low-permeability reservoirs and effectively analyzing the deliverability.Well test models must comply with the parti... Well testing is recognized as an effective means of accurately obtaining the formation parameters of low-permeability reservoirs and effectively analyzing the deliverability.Well test models must comply with the particular characteristics of flow in low-permeability reservoirs in order to obtain reasonable well test interpretation.At present,non-Darcy flow in low-permeability reservoirs is attracting much attention.In this study,displacement tests were conducted on typical cores taken from low-permeability reservoirs.Two dimensionless variables were introduced to analyze the collected experimental data.The results of the dimensionless analysis show whether non-Darcy flow happens or not depends on the properties of fluid and porous media and the pressure differential.The combination of the above three parameters was named as dimensionless criteria coefficient(DCC).When the value of the DCC was lower than a critical Reynolds number(CRN),the flow could not be well described by Darcy's law(so-called non-Darcy flow),when the DCC was higher than CRN,the flow obeyed Darcy's law.Finally,this paper establishes a transient mathematical model considering Darcy flow and non-Darcy flow in low-permeability reservoirs,and proposes a methodology to solve the model.The solution technique,which is based on the Boltzmann transformation,is well suited for solving the flow model of low-permeability reservoirs.Based on the typical curves analysis,it was found that the pressure and its derivative curves were determined by such parameters as non-Darcy flow index and the flow characteristics.The results can be used for well test analysis of low-permeability reservoirs. 展开更多
关键词 Low-permeability non-Darcy flow dimensionless analysis transient flow well testing
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UAV flight test of plasma slats and ailerons with microsecond dielectric barrier discharge 被引量:4
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作者 Zhi Su Jun Li +4 位作者 Hua Liang Bo-Rui Zheng Biao Wei Jie Chen Li-Ke Xie 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期455-464,共10页
Plasma flow control(PFC) is a promising active flow control method with its unique advantages including the absence of moving components, fast response, easy implementation, and stable operation. The effectiveness o... Plasma flow control(PFC) is a promising active flow control method with its unique advantages including the absence of moving components, fast response, easy implementation, and stable operation. The effectiveness of plasma flow control by microsecond dielectric barrier discharge(μs-DBD), and by nanosecond dielectric barrier discharge(NS-DBD) are compared through the wind tunnel tests, showing a similar performance between μs-DBD and NS-DBD. Furthermore, theμs-DBD is implemented on an unmanned aerial vehicle(UAV), which is a scaled model of a newly developed amphibious plane. The wingspan of the model is 2.87 m, and the airspeed is no less than 30 m/s. The flight data, static pressure data,and Tufts images are recorded and analyzed in detail. Results of the flight test show that the μs-DBD works well on board without affecting the normal operation of the UAV model. When the actuators are turned on, the stall angle and maximum lift coefficient can be improved by 1.3° and 10.4%, and the static pressure at the leading edge of the wing can be reduced effectively in a proper range of angle of attack, which shows the ability of μs-DBD to act as plasma slats. The rolling moment produced by left-side μs-DBD actuation is greater than that produced by the maximum deflection of ailerons,which indicates the potential of μs-DBD to act as plasma ailerons. The results verify the feasibility and efficacy of μs-DBD plasma flow control in a real flight and lay the foundation for the full-sized airplane application. 展开更多
关键词 plasma flow control flight test dielectric barrier discharge UAV
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An analytical poroelastic model for laboratorial mechanical testing of the articular cartilage (AC) 被引量:1
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作者 Xiaogang WU Kuijun CHEN +5 位作者 Zhaowei WANG Ningning WANG Teng ZHAO Yanan XUE Yanqin WANG Weiyi CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第6期813-828,共16页
The articular cartilage (AC) can be seen as a biphasic poroelastic material. The cartilage deformation under compression mainly leads to an interstitial fluid flow in the porous solid phase. In this paper, an analyt... The articular cartilage (AC) can be seen as a biphasic poroelastic material. The cartilage deformation under compression mainly leads to an interstitial fluid flow in the porous solid phase. In this paper, an analytical poroelastic model for the AC under laboratorial mechanical testing is developed. The solutions of interstitial fluid pressure and velocity are obtained. The results show the following facts. (i) Both the pressure and fluid velocity amplitudes are proportional to the strain loading amplitude. (ii) Both the amplitudes of pore fluid pressure and velocity in the AC depend more on the loading amplitude than on the frequency. Thus, in order to obtain the considerable fluid stimulus for the AC cell responses, the most effective way is to increase the loading amplitude rather than the frequency. (iii) Both the interstitiM fluid pressure and velocity are strongly affected by permeability variations. This model can be used in experimental tests of the parameters of AC or other poroelastic materials, and in research of mechanotransduction and injury mechanism involved interstitial fluid flow. 展开更多
关键词 articular cartilage (AC) poroelasticity interstitial fluid flow laboratorialmechanical test injury mechanism
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Modeling on Residence Time Distribution in Subsurface Flow Constructed Wetlands by Multi Flow Dispersion Model 被引量:2
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作者 ZHANG Tao SONG Xinshan +1 位作者 LU Shoubo YAN Denghua 《湿地科学》 CSCD 2010年第3期233-239,共7页
As an important design factor for constructed wetlands,hydraulic retention time and its distribution will affect the treatment performance.Instantaneously injected sodium chloride tracers were used to obtain residence... As an important design factor for constructed wetlands,hydraulic retention time and its distribution will affect the treatment performance.Instantaneously injected sodium chloride tracers were used to obtain residence time distributions of the lab scale subsurface flow constructed wetland.Considering the presence of trailing and multiple peaks of the tracer breakthrough curve,the multi flow dispersion model(MFDM)was used to fit the experimental tracer breakthrough curves.According to the residual sum of squares and comparison between the experimental values and simulated values of the tracer concentration,MFDM could fit the residence time distribution(RTD)curve satisfactorily,the results of which also reflected the layered structure of wetland cells,thus to give reference for application of MFDM to the same kind of subsurface flow constructed wetlands. 展开更多
关键词 subsurface flow constructed wetlands tracer test residence time distribution multi flow dispersion model
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mCT-Flow PET/CT性能测试及与mCT-S64-4R和16HR的比较
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作者 潘禾戎 姚杰 +5 位作者 戚鸣 茅娟莉 姚之丰 宋少莉 章英剑 张建平 《肿瘤影像学》 2021年第2期65-70,共6页
目的:研究mCT-Flow正电子发射计算机体层显像仪(positron emission tomography and computed tomography,PET/CT)性能,并将其性能的各项指标与mCT-S64-4R(简称mCT)和16HR进行比较。方法:PET部分使用专用测试模体,测试PET的空间分辨率、... 目的:研究mCT-Flow正电子发射计算机体层显像仪(positron emission tomography and computed tomography,PET/CT)性能,并将其性能的各项指标与mCT-S64-4R(简称mCT)和16HR进行比较。方法:PET部分使用专用测试模体,测试PET的空间分辨率、散射分数、真符合计数率、散射符合计数率、随机符合计数率、噪声等效计数率(noise equivalent count rate,NECR)和系统灵敏度。所得结果与mCT和16HR PET/CT的相应指标进行比较。CT部分测试定位光精度、噪声、图像均匀性、重建层厚偏差、高对比分辨率、低对比可探测能力、CT值线性、诊断床定位精度、CT剂量指数和水的CT值等性能参数。结果:mCT-Flow PET在偏视野(filed of view,FOV)中心1和10 cm处横向和轴向空间分辨率分别为4.51和4.41 mm及5.14和5.99 mm,另10 cm处的横断切向空间分辨率为4.60 mm;设备的散射分数为35%;NECR在18F溶液浓度为0.021 MBq/mL及k=1时峰值为117 kcps;在浓度为0.027 MBq/mL及k=0时峰值为165 kcps。系统灵敏度在FOV中心及偏中心10 cm处分别为9.24和9.14 cps/kBq。与mCT相比,两台设备的空间分辨率、峰值NECR、真符合计数率和随机符合计数率相近,散射符合计数率与散射分数稍低,但灵敏度稍有下降。与16HR相比,mCT-Flow空间分辨率稍高,散射分数更低,峰值NECR提高125%,灵敏度提高了51.9%(0 cm处)和49.6%(10 cm处)。CT各项指标均符合验收标准。结论:mCT-Flow PET/CT的各项测试指标均达到了标准要求。PET部分的主要性能指标与mCT相近,较16HR有所提高。 展开更多
关键词 mCT-flow PET/CT 性能测试 性能比较
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