Left Ventricular Systolic Intraventricular Flow Field Assessment in Hyperthyroidism Patients Using Vector Flow Mapping

Summary： Intraventricular hydrodynamics is considered an important component of cardiac function assessment. Vector flow mapping （VFM） is a novel flow visualization method to describe cardiac pathophysiological condition. This study examined use of new VFM and flow field for assessment of left ventricular （LV） systolic hemodynamics in patients with simple hyperthyroidism （HT）. Thirty-seven simple HT patients were enrolled as HT group, and 38 gender- and age-matched healthy volunteers as control group. VFM model was used to analyze LV flow field at LV apical long-axis view. The follow- ing flow parameters were measured, including peak systolic velocity （Vs）, peak systolic flow （Fs）, total systolic negative flow （SQ） in LV basal, middle and apical level, velocity gradient from the apex to the aortic valve （AV）, and velocity according to half distance （V1/2）. The velocity vector in the LV cavity, stream line and vortex distribution in the two groups were observed. The results showed that there were no significant differences in the conventional parameters such as left ventricular ejection fraction （LVEF）, left ventricular end-diastolic diameter （LVEDD） and left atrium diameter （LAD） between HT group and control group （P〉0.05）. Compared with the control group, a brighter flow and more vortexes were detected in HT group. Non-uniform distribution occurred in the LV flow field, and the stream lines were discontinuous in HT group. The values of Vs and Fs in three levels, SQ in middle and basal levels, AV and V1/2 were higher in HT group than in control group （P〈0.01）. AV was positively correlated with serum free thyroxin （FT4） （r=0.48, P〈0.01）. Stepwise multiple regression analysis showed that LVEDD, FT4, and body surface area （BSA） were the influence factors of △V. The unstable left ventricular sys- tolic hydrodynamics increased in a compensatory manner in simple PIT patients. The present study in- dicated that VFM may be used for early detection of abnormal ventricle contraction in clinical settings.

基于FLOW MAP和学科核心素养的初中生认知结构诊断与补救教学的个案研究

目前我国的基础教育改革目标转向对学生核心素养的培养。从培养学生核心素养的视角看待学生在纸笔测验中反映出的学情,及时进行教学补救,有利于实现核心素养的"落地"。通过运用FLOW MAP测查学优生A和中等生B在科学探究试题中暴露的认知结构,结合试题的学科核心素养水平的要求开展教学补救措施,以帮助学生优化认知结构,取得理想的学习效果,提升学科核心素养。

基于Flow Map的中美教材“氧化还原反应”难度比较

基于Flow Map对中美4种教材"氧化还原反应"内容难度的定量统计表明,中美教材的整合广度和表征深度的差异明显,美国教材的整合广度和表征深度均明显大于中国教材,即美国教材的相关难度较小;质性评价表明,美国教材以"化学变化中的电子"为认识核心,构建了"得失氧—氧的电负性与电子得失—氧化数与电子得失"的认知脉络,采用"电负性"作为先行组织者,更多运用对比与比较、情境推理与解释等信息处理策略,整合了大量的氧化还原反应应用类的知识。

Eulerian Algorithms for Computing the Forward Finite Time Lyapunov Exponent Without Finite Difference Upon the Flow Map

In this paper,effective Eulerian algorithms are introduced for the computation of the forwardfinite time Lyapunov exponent(FTLE)of smoothflowfields.The advantages of the proposed algorithms mainly manifest in two aspects.First,previous Eulerian approaches for computing the FTLEfield are improved so that the Jacobian of theflow map can be obtained by directly solving a corresponding system of partial differential equations,rather than by implementing certainfinite difference upon theflow map,which can significantly improve the accuracy of the numerical solution especially near the FTLE ridges.Second,in the proposed algorithms,all computations are done on thefly,that is,all required partial differential equations are solved forward in time,which is practically more natural.The new algorithms still maintain the optimal computational complexity as well as the second order accuracy.Numerical examples demonstrate the effectiveness of the proposed algorithms.

Spatio-temporal flow maps for visualizing movement and contact patterns

The advanced telecom technologies and massive volumes of intelligent mobile phone users have yielded a huge amount of real-time data of people’s all-in-one telecommunication records,which we call telco big data.With telco data and the domain knowledge of an urban city,we are now able to analyze the movement and contact patterns of humans in an unprecedented scale.Flow map is widely used to display the movements of humans from one single source to multiple destinations by representing locations as nodes and movements as edges.However,it fails the task of visualizing both movement and contact data.In addition,analysts often need to compare and examine the patterns side by side,and do various quantitative analysis.In this work,we propose a novel spatio-temporal flow map layout to visualize when and where people from different locations move into the same places and make contact.We also propose integrating the spatiotemporal flow maps into existing spatiotemporal visualization techniques to form a suite of techniques for visualizing the movement and contact patterns.We report a potential application the proposed techniques can be applied to.The results show that our design and techniques properly unveil hidden information,while analysis can be achieved efficiently.

Assessment of angiographic coronary slow flow phenomenon with intracoronary ultrasound and doppler flow mapping

In order to study the mechanism of angiographic coronary slow flow phenomenon (SF), intracoronary ultrasound (ICUS) and Doppler (ICD) were performed in 14 patients with angiographic SF phenomenon but with normal angiograms and in 16 patients with normal angiographic coronary flow (NF). A 3.5 F, 20 MHz ultrasound catheter (Boston Scientific) was used for ICUS and a 0.014 inch FloWire (Cardiometrics) was used for ICD. Coronary flow velocity including average peak velocity (APV), maximal peak velocity (MPV) at rest and at hyperemia as well as coronary flow reserve (CFR) were compared in both groups in comparison to the presence or absence of plaque formation based on ICUS. CFR in the SF group (4.2±1.1) was even higher than that of the NF group (3.1±0.6, P<0.001). Department of Cardiology, University GHS Essen, Germany (Ge JB, Simon H, Jeremias A, Liu FQ, Grge G, Haude M, Baumgart D and Erbel R) Significant differences were also found concerning the APV and MPV among both groups (both P <0.001). Plaque formation was found in 7/13 patients with a lumen reduction of 21%±24% in SF group and in 7/16 of the NF group with a lumen reduction of 19%±17%. Comparison of APV, MPV and CFR in SF and NF grups. Comparison of APV, MPV and CFR in SF and NF groups[BHDFG1*2,WK8ZQ1,WK11DW,WK11DWW] SF group NF groupAPV (cm/s) Rest 7.7±2.0 21.1±5.0 * Peak31.7±14.961.3±14.2 *MPV (cm/s) Rest17.4±4.637.0±11.4 * Peak56.8±14.981.8±17.7 *CFR4.2±1.13.1±0.6 # * P<0.001, #P=0.002. Coronary slow flow phenomenon in angiography indicates reduced resting flow velocity without reduction of coronary flow reserve.

STOCHASTIC FLOWS OF MAPPINGS

In this paper, the stochastic flow of mappings generated by a Feller convolution semigroup on a compact metric space is studied. This kind of flow is the generalization of superprocesses of stochastic flows and stochastic diffeomorphism induced by the strong solutions of stochastic differential equations.

A control method applied to mixed traffic flow for the coupled-map car-following model

In light of previous work [Phys. Rev. E 60 4000 （1999）], a modified coupled-map car-following model is proposed by considering the headways of two successive vehicles in front of a considered vehicle described by the optimal velocity function. The non-jam conditions are given on the basis of control theory. Through simulation, we find that our model can exhibit a better effect as p = 0.65, which is a parameter in the optimal velocity function. The control scheme, which was proposed by Zhao and Gao, is introduced into the modified model and the feedback gain range is determined. In addition, a modified control method is applied to a mixed traffic system that consists of two types of vehicle. The range of gains is also obtained by theoretical analysis. Comparisons between our method and that of Zhao and Gao are carried out, and the corresponding numerical simulation results demonstrate that the temporal behavior of traffic flow obtained using our method is better than that proposed by Zhao and Gao in mixed traffic systems.

Heat flow of harmonic maps from noncompact manifolds

The global existence of the heat flow for harmonic maps from noncompact manifolds is considered. When L^m norm of the gradient of initial data is small, the existence of a global solution is proved.

EXISTENCE AND NONUNIQUENESS FOR THE HEAT FLOW OF INHOMOGENEOUS HARMONIC MAP EQUATION

A weak solution to the heat flow problems is constructed.Nonuniqueness results of such solutions are also shown when the first data is a weak solution to the Euler Lagrange equation but not a weakly stationary solution to it.

UNCERTAINTY ANALYSIS ON ZONATION MAPS OF DEBRISFLOW HAZARD IN YUNNAN PROVINCE,CHINA

Different researchers select different factors and use different methods to assess the regional hazard degrees of debris now. consequenily, even for the same region, tb.. are often different hazard zonation maps, and there must be some uncertainty in the zonations. Thus the ceriainty analysis of zonation maps becomes obviously important.For debris now hazard, those zonation maps with a certainty analysis could provide most valuable information for land users, hazard managers and policy makers. By comparison of three researchers’ findings in Yunnan Province, this paPer shows that seven to nine iafluential factors are chosen for the zonation maps. spatial density of debris flow ravines,regional average rock-weathering coefficient, yearly precipitation, days of≥50 mm daily rainfall, and proportion of sloping land with slope≥25℃to the total land are the most acceptable factors. Mathemahcal methods of maximum-minimumvalues, upperlower limit values and Fuzzy values are used to quantify the factors. Step-by-step methodoogy is commonly used for the zonation maps. Research results show that mchmum uncedrinty is 66. 6% and minimum uncertainty is 35.7% in debris now hazard maps of zhaotong Prefecture and Yunnan Province. Therefore there is still much work for us to improve the zonation methedology.

Flow Stress Behavior and Processing Map of Al-Cu-Mg-Ag Alloy during Hot Compression

The hot deformation behavior of Al-Cu-Mg-Ag was studied by isothermal hot compression tests in the temperature range of 573-773 K and strain rate range of 0.001-1 s^-1 on a Gleeble 1500 D thermal mechanical simulator. The results show the flow stress of Al-Cu-Mg-Ag alloy increases with strain rate and decreases after a peak value, indicating dynamic recovery and recrystallization. A hyperbolic sine relationship is found to correlate well the flow stress with the strain rate and temperature, the flow stress equation is estimated to illustrate the relation of strain rate and stress and temperature during high temperature deformation process. The processing maps exhibit two domains as optimum fields for hot deformation at different strains, including the high strain rate domain in 623-773 K and the low strain rate domain in 573-673 K.

A Framework to Regionalize Flow Information in a Catchment with Limited Hydrological Data

This paper describes a framework for mapping flow information from a single gauge to the 9-ungauged river basins with distinct attributes. To establish the basic watershed characteristics at the gauged site, a hydrologic model was calibrated and validated against the historical continuous discharge dataset. The framework was then applied to account for the two watersheds’ proportionality in their similarity, such as the influence of land use on transplanting flow signatures to the ungauged site. Three land-use scenarios-discharges at the ungauged and gauged sites formed the basis of an equation mapping the gauged discharge signal to the ungauged site. In comparison with intermittent observed data, the framework prediction attained a precision of 0.85 ≥ NSE ≤ 0.95, 0.80 ≥ R2 ≤ 0.94, 0.56 ≥ bR2 ≤ 0.89. Despite considerable differences in the watershed area, slope, soils, and land cover, the framework satisfactorily depicted the variation in flow pulses at each of the 9 ungauged discharge sites. In the absence of sufficient hydrological information, for example, the presence of a single gauge, the framework provides an alternative method to estimate flow at ungauged sites, reducing uncertainties in the regionalization of model parameters.

基于bit-map算法的DMA数据流仲裁器设计

针对集成电路产业快速发展所需要的复杂通信要求,设计了一种基于bit-map算法的DMA数据流仲裁器。DMA数据流仲裁器由通道优先级bit-map映射模块、通道请求生成模块、通道请求仲裁模块、通道授权标志生成模块和外设请求应答模块组成。在完成逻辑设计后,通过UVM验证方法学对电路的各个功能进行验证。验证结果表明,本设计仅使用一个32位bit-map映射寄存器将8条通道的32种优先级配置映射到对应有效位,便可实现对8条通道DMA请求的仲裁,无需配置优先级比较电路,不会因逐级比较产生优先级配置相互干扰的问题,且在后期生成实际电路的过程中可以减小电路面积、降低电路功耗。

铸态30CrMnSiNi2A钢的热变形行为与热加工图

目的研究铸态30CrMnSiNi2A钢的热变形行为,并建立热加工图评估出合适的热变形参数。方法在变形温度900~1200℃和应变速率0.01~10 s^(−1)条件下开展热压缩实验,分别构建应变0.2、0.4、0.6、0.8下的热加工图,结合扫描电镜对变形后的微观组织进行分析。结果30CrMnSiNi2A钢在压缩过程中真应力的变化是加工硬化和动态软化协同作用的结果;在低应变速率时(0.01、0.1 s^(−1)),流动曲线在应力值达到峰值应力(σp)后都表现出流动软化现象,而在高应变速率下流动曲线则表现出连续的加工硬化现象。结论根据变形试样的微观组织和塑性流动是否稳定,可将热加工图分为3个区:流动失稳区、不完全动态再结晶区、完全动态再结晶区,在完全动态再结晶区内的晶粒细小均匀,所以将变形温度1100~1180℃、应变速率0.01~0.5 s^(−1)确定为适合于30CrMnSiNi2A钢的加工窗口。

基于CT灌注扫描彩色血流图预测经血管内治疗急性缺血性卒中患者术后脑水肿程度的价值

目的:探讨基于CT灌注扫描彩色血流图在预测经血管内治疗前循环狭窄所致缺血性卒中脑水肿程度的价值,并建立诺谟图风险模型评估中重度脑水肿风险。方法:回顾性分析本院63例经血管内治疗(术后mTICI分级≥2b级)的前循环狭窄所致急性缺血性卒中患者,所有患者行颅脑CT灌注(CTP)扫描,基于CTP扫描源数据重建彩色血流图(FVM)并进行评分。基于DSA检查行ASITN/SIR侧支循环评估。基于复查CT患者脑肿胀程度进行评分(0~3分),将0~1分定义为轻度水肿组;2~3分定义为中重度水肿组。统计两组间在心血管危险因素、NIHSS评分、ASPECT评分、FVM评分、核心梗死区体积、低灌注区体积、缺血半暗带体积之间的差异,二元logistic回归用于分析中重度脑水肿发生的危险因素,并构建诺谟图(Nomogram)风险模型,建立受试者工作特征曲线及校准曲线验证其效能。结果:轻度水肿组44人,中重度水肿组19人。单因素分析显示轻度水肿组年龄、核心梗死区体积小于中重度水肿组(P>0.05);FVM评分高于中重度水肿组(P>0.05)。二元logistics分析显示核心梗死区体积(OR=1.038,95%CI=1.006~1.072,P=0.021)、FVM评分(OR=0.268,95%CI=0.116~0.623,P=0.002)是中重度水肿的独立预测因素。基于独立预测因素构建的诺谟图模型曲线下面积为0.893(95%CI=0.817~0.969,P<0.01)。校准曲线及Hosmer-Lemeshow检验显示该模型预测符合度(P=0.723)良好。结论:低FVM评分、高核心梗死区体积是经血管内治疗急性前循环闭塞AIS患者发生中重度脑水肿的独立危险因素,基于两者构建的Nomogram模型可以有效评估中重度脑水肿风险。

动态场景下基于实例分割与光流的语义SLAM建图

视觉同步定位与建图技术常用于室内智能机器人的导航,但是其位姿是以静态环境为前提进行估计的。为了提升视觉即时定位与建图(Simultaneous Localization And Mapping,SLAM)在动态场景中的定位与建图的鲁棒性和实时性,在原ORB-SLAM2基础上新增动态区域检测线程和语义点云线程。动态区域检测线程由实例分割网络和光流估计网络组成,实例分割赋予动态场景语义信息的同时生成先验性动态物体的掩膜。为了解决实例分割网络的欠分割问题,采用轻量级光流估计网络辅助检测动态区域,生成准确性更高的动态区域掩膜。将生成的动态区域掩膜传入到跟踪线程中进行实时剔除动态区域特征点,然后使用地图中剩余的静态特征点进行相机的位姿估计并建立语义点云地图。在公开TUM数据集上的实验结果表明,改进后的SLAM系统在保证实时性的前提下,提升了其在动态场景中的定位与建图的鲁棒性。

思维导图联合流程图在血管外科急诊教学中的应用

目的:探讨思维导图联合流程图这一可视化的新型教学工具在血管外科急诊教学改革中的应用价值。方法:通过该教学工具在血管外科急诊教学的课前准备环节、课堂实施、课后归纳复习、课程评价维护中的具体应用,评价该模式的教学效果。结果:思维导图联合流程图可将医学理论知识可视化,培养医学生的抽象临床思维,最终建立完整的知识架构。结论:结合血管外科急诊疾病的病情危急、疾病谱广、实践性及时间性强等特点,思维导图联合流程图可作为一种新型教学工具,应用于血管外科急诊教学改革中。

Development of Measurement System for Flow and Shape Using Array Ultrasonic Sensors

In Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, the fuel debris formed in the Reactor Pressure Vessel (RPV) and Primary Containment Vessel (PCV) at Unit 1 - 3. To accelerate and decide further decommissioning steps of the FDNPP, it is crucial to obtain realistic information of the debris and localize contaminated water leakage from PCV. Due to high radiation and dark environment inside the PCV, investigating instruments and techniques should necessarily to meet specification of radiation resistance, waterproofness, dust resistance and so on. This study focuses on development of ultrasonic measurement system using a couple of sectorial array sensors to localize contaminated water leakage and visualize shape of object that repre- senting fuel debris, simultaneously. In this study, Total Focusing Method (TFM) and Ultrasonic Velocity Profiler (UVP) methods are considered to visualize object shape and flow pattern around it, respectively. To demonstrate applicability and reliability of developed measurement system with sectorial array sensors, a mock-up experiment result of simulated water leakage and fuel debris shape were discussed in this paper.

油液多层过滤去固分离及特性分析

针对油-固体系中单层滤网无法同时满足过滤精度高与使用寿命长的问题,采用多层过滤器并对其去固分离特性展开分析。通过耦合流场控制方程、颗粒运动方程、颗粒-壁面碰撞模型方程,建立了适用油-固体系的多层过滤数值分析模型,探究了油-固体系中多层过滤器的去固分离特性,分析了入口流速和滤网层数对流场特性及过滤比(β)的影响。结果表明:多层过滤器可有效过滤孔径与粒径比(k_(d))大于15的固体颗粒;增加滤网层数,d_(5)和d_(20)(β分别为5和20时对应的颗粒粒径)显著降低;增大入口流速,d_(5)和d_(20)变化较小;当β<5时,颗粒粒径的变化对过滤比的影响较小;当β>5时,颗粒粒径的小幅增大可能导致过滤比显著提高。