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关键词： 微压计   检定   管式   工作液体   示值超差   仪器   零位  

摘要： 一、调配工作液体及冲洗仪器 有些检定员在拿到斜管式微压计（以下简称“微压计”）后，发现盒状容器内盛有工作液体，调整好零位后马上检定，结果示值超差。

关键词： 叶栅   流场   攻角   数值模拟   流动损失  

摘要： 以某型航空发动机的压气机平面叶栅为研究对象,基于Gambit软件建立叶栅模型并划分网格,采用Fluent软件,仿真计算了不同攻角时叶栅通道内流场的流动情况,比较分析了不同攻角时叶栅通道的流动特性。仿真结果对压气机的设计和改进具有一定的指导意义。

关键词： 流体包裹体   花岗闪长岩   锆石U-Pb测年   矽卡岩   西昆仑造山带  

摘要： 班迪尔司热洪铜铁矿区位于西昆仑造山带西北部,铜铁矿化分布在花岗闪长岩体与碳酸盐岩的接触带上,受控于矽卡岩带,成矿与花岗闪长岩具有密切的时间、空间关系。本文对该矿床中与成矿关系密切的花岗闪长岩进行了详细的锆石U-Pb年代学研究,结果表明,LA-ICP-MS锆石U-Pb测年获得班迪尔司热洪花岗闪长岩成岩年龄为239.8±1.5Ma,表明成矿作用发生在早中三叠世。根据矿物组合和脉体穿插关系,班迪尔司热洪铜铁矿可分为4个成矿阶段：矽卡岩阶段、退化矽卡岩阶段、石英-硫化物阶段和碳酸盐阶段,石英-硫化物阶段为主成矿阶段。主成矿阶段石英脉中广泛发育流体包裹体,分别为气液两相包裹体（W型）、含子矿物三相包裹体（S型）和含CO2包裹体（C型）三类。流体包裹体研究表明,包裹体均一温度为145.5~304℃,盐度范围为0.9%~33.1%NaC leqv,成矿流体为H20-CO2-NaC l体系。班迪尔司热洪铜铁矿地质特征和成矿流体特征表明,班迪尔司热洪铜铁矿为热液交代矽卡岩型矿床,区域断裂为成矿岩浆提供运移通道,岩浆侵位发育矽卡岩型岩浆流体系统,并伴随着Cu、Fe矿化。

关键词： 文丘里流量计   数值模拟   喉径比   收缩锥角   流动特性  

摘要： 利用Ansys Fluent软件对文丘里管中流体流动状况进行了数值模拟,主要讨论了不同流量下文丘里管收缩锥度和喉段缩径比对文丘里管压降和流场的影响:当收缩锥度为定值时,进出口的压差将随着缩径比的增大而减小;当缩径比一定时,进出口压差随着收缩锥度的增大而增大。数值模拟结果与实验值吻合度较高,基本偏差控制在0.2以下。模拟分析结果对于一定的管路系统设计和选择合适结构参数的流量计具有一定的指导意义。

关键词： power loss   DC-power flow   smart grid   distributed energy resource   distributed control   tie-set graph theory   TIE-SET GRAPH  

摘要： In this paper, a novel decentralized algorithm is proposed to minimize power flow loss in a large-scale future grid connecting with many real-time-distributed generation systems by which power flows bi-directionally. The DC-power loss at each link is defined as the product of resistance and the square of current that can be considered as a quadratic flow cost. We employ the notion of tie-sets that reduces the complexity of the power flow loss problem by dividing a power network into a set of loops that forms a linear vector space on which the power loss problem can be formulated as a convex optimization problem. As finding a solution in each tie-set enables global optimization, we realize parallel computing within a system of independent tie-sets by integrating autonomous agents. Simulation results demonstrate the minimization of the power loss on every link by iteratively optimized power flows and show the superiority against the traditional centralized optimization scheme. Copyright (c) 2014 John Wiley & Sons, Ltd.

关键词： Human robot environments   boosting algorithms   people versus robot detection   optical flow-based features   PEDESTRIAN DETECTION   HISTOGRAMS   SPACE  

摘要： The goal of this work is to distinguish between humans and robots in a mixed human-robot environment. We analyze the spatio-temporal patterns of optical flow-based features along several frames. We consider the Histogram of Optical Flow (HOF) and the Motion Boundary Histogram (MBH) features, which have shown good results on people detection. The spatio-temporal patterns are composed of groups of feature components that have similar values on previous frames. The groups of features are fed into the FuzzyBoost algorithm, which at each round selects the spatio-temporal pattern (i.e. feature set) having the lowest classification error. The search for patterns is guided by grouping feature dimensions, considering three algorithms: (a) similarity of weights from dimensionality reduction matrices, (b) Boost Feature Subset Selection (BFSS) and (c) Sequential Floating Feature Selection (SFSS), which avoid the brute force approach. The similarity weights are computed by the Multiple Metric Learning for large Margin Nearest Neighbor (MMLMNN), a linear dimensionality algorithm that provides a type of Mahalanobis metric Weinberger and Saul, J. MaCh. Learn. Res. 10 (2009) 207-244. The experiments show that FuzzyBoost brings good generalization properties, better than the GentleBoost, the Support Vector Machines (SVM) with linear kernels and SVM with Radial Basis Function (RBF) kernels. The classifier was implemented and tested in a real-time, multi-camera dynamic setting.

关键词： Ventricular assist devices (VAD)   Rotodynamic pumps   Continuous flow   Pulsatile flow   Particle image velocimetry (PIV)   Flow coefficient   Regime map   VENTRICULAR ASSIST DEVICE   CIRCULATORY SUPPORT   PIV MEASUREMENTS   FLUID-DYNAMICS   PULSATILE  

摘要： Rotodynamic blood pumps (also known as rotary or continuous flow blood pumps) are commonly evaluated in vitro under steady flow conditions. However, when these devices are used clinically as ventricular assist devices (VADs), the flow is pulsatile due to the contribution of the native heart. This study investigated the influence of this unsteady flow upon the internal hemodynamics of a centrifugal blood pump. The flow field within the median axial plane of the flow path was visualized with particle image velocimetry (PIV) using a transparent replica of the Levacor VAD. The replica was inserted in a dynamic cardiovascular simulator that synchronized the image acquisition to the cardiac cycle. As compared to steady flow, pulsatile conditions produced periodic, transient recirculation regions within the impeller and separation in the outlet diffuser. Dimensional analysis revealed that the flow characteristics could be uniquely described by the non-dimensional flow coefficient (Phi) and its time derivative (Phi), thereby eliminating impeller speed from the experimental matrix. Four regimes within the Phi-Phi plane were found to classify the flow patterns, well-attached or disturbed. These results and methods can be generalized to provide insights for both design and operation of rotodynamic blood pumps for safety and efficacy.

关键词： MPO - myeloperoxidase   ALL - acute lymphoblastic leukaemia   AML -acute myeloid leukaemia   MPAL -mixed phenotypic acute leukaemia   FCM -flow cytometry   ACUTE MYELOID-LEUKEMIA   CLASSIFICATION   PROPOSALS  

摘要： Objectives: Myeloperoxidase (MPO) detection either by enzyme cytochemistry (cMPO) or flow cytometry (fMPO) plays a major role in acute leukaemia (AL) diagnosis as per World Health Organization (WHO) 2008 classification. Although 3% cMPO was recommended as positivity, no specific cut-off had been mentioned by WHO for fMPO. Various authors recommend different cut-offs ranging from 3 to 28% for fMPO. The aim of this study was to analyse fMPO cut-offs ranging from 3 to 10% in classifying AL and to assess whether a new cut-off could be suggested. Methods: Totally, 216 cases of AL were retrospectively analysed for fMPO ranging from 3 to 10% and compared with gold standard. Presence of cMPO (>= 3%) and/or expression of two or more pan-myeloid markers (CD13, CD33, and CD117) in the absence of CD19 and CD3 were kept as gold standard for diagnosis of acute myeloid leukaemia (AML). Results: Sensitivities for classifying AL as AML/mixed phenotypic acute leukaemia (MPAL) at 3, 5.4, and 10% were 98.3, 98.3, and 96.6%, respectively, whereas specificities at this cut-off were 22.2, 91, and 71%, respectively. Discussion: Only few studies have been done in this aspect to define a consistent cut-off for fMPO for proper classification of acute leukaemias. This was one of the largest and few studies available till date in this regard. Conclusion: The newer cut-off for fMPO (5.4%) emerged out from our study with best sensitivity and specificity for accurately classifying AL cases into acute lymphoblastic leukaemia, AML, and MPAL.

关键词： LIMIT-SETS   EQUIDISTRIBUTION   ORBITS  

摘要： Let G be a connected simple linear Lie group of rank one, and let I" < G be a discrete Zariski dense subgroup admitting a finite Bowen-Margulis-Sullivan measure m (BMS). We show that the right translation action of the one-dimensional diagonalizable subgroup is mixing on (I"G, m (BMS)). Together with the work of Roblin, this proves ergodicity of the Burger-Roblin measure under the horospherical group N, establishes a classification theorem for N invariant Radon measures on I"G, and provides precise asymptotics for the Haar measure matrix coefficients.

关键词： flow cytometry   polyploidy   seed   taxonomy   PLOIDY LEVEL   GENOME SIZE   AGGREGATE   L.   EVOLUTION   POLYGONACEAE   BIOGEOGRAPHY   COEXISTENCE   MORPHOLOGY   BIOLOGY  

摘要： Portulaca oleracea is a noxious annual weed of worldwide distribution in temperate to tropical climates. Its taxonomy has been treated in contradictory ways in the past. Various microspecies have been described, lumped into a single species by other authors. We re-examined the importance of seed size and ploidy variation, previously applied as the most important taxonomic characters, for systematic classification based on accessions from Europe, Asia, Africa and South America using flow cytometry, chromosome counting and morphometry. Sixteen microspecies and six transitional forms, covering the ploidy and seed character variation, proposed for the complex, were studied from 178 populations. Portulaca grandiflora was included as a reference species from outside the complex. DNA hyper-pentaploidy or hexaploidy were inferred for the majority of accessions which exhibited the full range of seed size. It is recommended that the only species of lower ploidy (either diploid based on x=12 or tetraploid based on x=12) encountered, ***, should be separated from the *** complex as it deviates in base chromosome number and monoploid genome size. The frequency distribution of seed size was continuous and unimodal within the wild taxa of the complex and in pairs of taxa defined by testa sculpture. Seed size of DNA hexaploids was slightly negatively correlated with sample/standard fluorescence intensities. Our results conflict with the current microspecies concept. Possible reasons underlying the discrepancy are discussed and strategies for future systematic research are suggested.(c) 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179, 144-156.