Real-time Three-dimensional Echocardiographic Assessment of Left Ventricular Remodeling Index in Patients with Hypertensive Heart Disease and Coronary Artery Disease

Left ventricular remodeling index （LVRI） was assessed in patients with hypertensive heart disease （HHD） and coronary artery disease （CAD） by real-time three-dimensional echocardiography （RT3DE）. RT3DE data of 18 patients with HHD, 20 patients with CAD and 22 normal controis （NC） were acquired. Left ventricular end-diastolic volume （EDV） and left ventricular end-diastolic epicardial volume （EDVepi） were detected by RT3DE and two-dimensional echocardiography Simpson biplane method （2DE）. LVRI （left ventricular mass/EDV） was calculated and compared. The results showed that LVRI measurements detected by RT3DE and 2DE showed significant differences inter-groups （P〈0.01）. There was no significant difference in NC group （P〉0.05）, but significant difference in HHD and CAD intra-group （P〈0.05）. There was good positive correlations between LVRI detected by RT3DE and 2DE in NC and HHD groups （t=0.69, P〈0.01; r=0.68, P〈0.01）, but no significant correlation in CAD group （r=0.30, P〉0.05）. It was concluded that LVRI derived from RT3DE as a new index for evaluating left ventricular remodeling can provide more superiority to LVRI derived from 2DE.

Comparison of delay compensation methods for real-time hybrid simulation using frequency-domain evaluation index

The delay compensation method plays an essential role in maintaining the stability and achieving accurate real-time hybrid simulation results. The effectiveness of various compensation methods in different test scenarios, however, needs to be quantitatively evaluated. In this study, four compensation methods （i.e., the polynomial extrapolation, the linear acceleration extrapolation, the inverse compensation and the adaptive inverse compensation） are selected and compared experimentally using a frequency evaluation index （FEI） method. The effectiveness of the FEI method is first verified through comparison with the discrete transfer fimction approach for compensation methods assuming constant delay. Incomparable advantage is further demonstrated for the FEI method when applied to adaptive compensation methods, where the discrete transfer function approach is difficult to implement. Both numerical simulation and laboratory tests with predefined displacements are conducted using sinusoidal signals and random signals as inputs. Findings from numerical simulation and experimental results demonstrate that the FEI method is an efficient and effective approach to compare the performance of different compensation methods, especially for those requiring adaptation of compensation parameters.

Real-time acquisition of compact volumetric maps

Building compact 3D maps of the environment models has become an important research topic. This paper presented an efficient stream decimation algorithm of massive meshes. The algorithm adapted the pre-processing step leading to lower in-corn memory consumption. This algorithm is applied to reconstructing compact terrain with mobile robot, achieving satisfying results.

A Model Predictive Scheduling Algorithm inReal-Time Control Systems

Abstract-The ineffective utilization of power resources has attracted much attention in current years. This paper proposes a real-time distributed load scheduling algorithm considering constraints of power supply. Firstly, an objective function is designed based on the constraint, and a base load forecasting model is established when aggregating renewable generation and non-deferrable load into a power system, which aims to transform the problem of deferrable loads scheduling into a distributed optimal control problem. Then, to optimize the objective function, a real-time scheduling algorithm is presented to solve the proposed control problem. At every time step, the purpose is to minimize the variance of differences between power supply and aggregate load, which can thus ensure the effective utilization of power resources. Finally, simulation examples are provided to illustrate the effectiveness of the proposed algorithm.

Intelligent compaction theory of high roller compacted concrete dam

The concept and realization process of intelligent compaction for the construction of high roller compacted concrete dam were presented, as well as the theory of monitoring and intelligent feedback control. Based on the real-time analysis of the compaction index, a multiple regression model of the dam compactness was established and a realime estimation method of compaction quality for the entire work area of roller compacted concrete dam was proposed finally. The adaptive adjustment of the roiling process parameters was achieved, with the speed, the exciting force, the roller pass and the compaction thickness meeting the standards during the whole construction process. As a result, the compaction quality and construction efficiency can be improved. The research provides a new way for the construction quality control of roller compacted concrete dam.

High Accuracy and Real-Time Gated Viewing Laser Radar

A gated viewing laser radar has an excellent performance in underwater low light level imaging, and it also provides a viable solution to inhibit backscattering. In this paper, a gated viewing imaging system according to the demand for real-time imaging is presented, and then the simulation is used to analyze the performance of the real-time gated viewing system. The range accuracy performance is limited by the slice number, the width of gate, the delay time step, the initial delay time, as well as the system noise and atmospheric turbulence. The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters. Finally, how to choose the optimal parameters has been researched.

针片状骨料含量对沥青混凝土骨料级配的影响研究

为研究针片状骨料含量对沥青混凝土骨料级配的影响,本文采用逐级填充法,选用骨架稳定性为衡量骨架级配优劣的唯一指标,考虑针片状含量为0%、20%、25%、30%、35%,利用垂直振动压实仪成型试件。结合加州承载比(CBR)值、骨架密度与空隙率综合评价骨架稳定性,以此确定各组粗骨料级配。采用合成级配的设计方法,将粗细集料进行全粒径骨料级配设计。结果表明,随着针片状骨料含量的增加,全粒径骨料骨架稳定性呈现先增后减的趋势,其中针片状骨料含量为30%的骨架稳定性最优,针片状骨料含量35%的稳定性最劣。

基于粒子群的旧工业建筑再利用空间优化算法

为了解决土地资源紧张的问题,优化旧工业建筑空间,提高建筑利用空间紧密度,实现空间再利用,提出基于粒子群的旧工业建筑再利用空间优化算法。将土地利用适宜性最大化、用地紧凑度最大化和转化成本最小化作为优化目标,构建空间优化模型,建立旧工业建筑再利用空间优化目标函数,在相关条件的约束下采用粒子群算法求解上述目标函数,实现旧工业建筑再利用空间的优化。仿真结果表明,所提方法的地类转换成本低,总适宜度、生态协调性和社会效益高,空间紧凑度高,优化效率高。

振动轮两侧加速度差异及连续压实指标优化研究

连续压实控制技术主要通过振动轮单侧振动响应描述土体压实状态,已在工程中得到广泛应用。然而,研究发现压实过程中存在振动轮两侧加速度响应不一致的现象,这可能导致现有测试方法在相同位置出现不同的刚度测试结果,因此研究振动轮两侧振动差异性对提高连续压实测试精度具有重要意义。结合现场试验,采集压路机振动轮两侧的加速度信号,重点分析了不同压实遍数、振动频率下两侧加速度峰值、倍频幅值的变化与分布规律;以双侧响应为基础提出平均指标,通过相关性分析对指标适用性进行验证。研究结果表明:随着压实遍数的增加,两侧加速度峰值差异逐渐减小,经4遍压实后差异由24.4%降至13.3%;振动轮结构偏心会造成振动轮两侧加速度频谱中基频幅值差异的产生,被压土体两侧刚度不均会造成2倍频、3倍频幅值差异的产生;双侧平均指标μAICV与动态变形模量的相关性为0.75,表明双侧平均指标μAICV可用于路基压实质量控制,相比单侧连续压实控制指标,可有效提高现场质量控制精度。

基于液化砂土地基等能量等变形挤密群桩现场试验规律分析

为解决地震导致地基饱和砂土和粉土液化,造成建筑沉降、倾斜甚至破坏的发生,以海南省海口市江东新区房建项目砂性地基土严重液化为依托,采用等能量等变形挤密桩技术进行桩周土的二次挤密加固,通过加固前后标准贯入度试验击数计算液化指数(I_(LE)),再进行单桩竖向抗压静载试验检验承载力。现场试验得出,处理深度内整体地基土由原严重液化程度改善为轻微液化趋近于不液化;前后标贯随深度平均锤击数之差拟合方程为Y=0.307857X+10.3617,R^(2)=0.84792,Pearson系数为0.93109,前后标贯平均击数在-5 m至-13 m区间内每层提高12~15击,各土层加固均匀;加固后地基达到单桩承载力设计特征值2250 kN。研究规律可供类似工程提供参考。

自密实全再生混凝土单轴受压性能及强度指标换算关系研究

为深入了解自密实全再生混凝土单轴受压力学性能,以水胶比(0.36、0.40、0.45)与粉煤灰掺量(20%、30%、40%、50%、70%)为变化参数,设计并制作11组(共99个)自密实全再生混凝土试件对其立方体抗压强度、轴心抗压强度和弹性模量进行试验研究,观察试件受压破坏过程及破坏形态,获取各力学性能指标的变化趋势,基于试验结果及现有文献成果,建立强度指标换算关系,并提出自密实全再生混凝土的本构方程。研究表明:自密实全再生混凝土受压破坏过程及破坏形态与普通混凝土相似,总体上自密实全再生混凝土立方体抗压强度、轴心抗压强度及弹性模量随水胶比、粉煤灰掺量的增加而降低,所提计算式可较好预测自密实全再生混凝土的单轴受压性能指标及本构关系。

基于断层岩压实成岩程度指数的断裂侧向封闭时空分布预测方法及其应用

为了研究含油气盆地受断裂控制圈闭中油气分布规律,在断裂侧向封闭机理及与断层岩压实成岩程度之间关系研究的基础上,通过断层岩压实成岩程度指数空间分布和断裂侧向封闭所需的最小断层岩压实成岩程度指数,确定断裂侧向封闭空间的分布;通过不同地质时期断层岩古压实成岩程度指数恢复和断裂侧向封闭所需的最小断层岩压实成岩程度指数,确定断裂侧向封闭时间的分布;二者结合建立了一套基于断层岩压实成岩程度指数的断裂侧向封闭时空分布预测方法,并利用其预测渤海湾盆地歧口凹陷大张坨断裂在沙河街组一段(沙一段)下亚段内断裂侧向封闭的时空分布。结果表明:除了西部端部外,大张坨断裂其余部位在沙一段下亚段内的皆为封闭部位;从距今1.17 Ma至现今,大张坨断裂在沙一段下亚段内皆处于封闭状态,较有利于下伏沙河街组三段(沙三段)源岩生成油气在大张坨断裂处沙一段下亚段内聚集与保存;与已知大张坨断裂处沙一段下亚段的油气富集规律相吻合。研究成果证实了该方法用于断裂侧向封闭时空分布预测是可行的。

基于PECVD的SiO_(2)薄膜制备研究进展

二氧化硅(SiO_(2))薄膜因其卓越的光学性能,在半导体器件、集成电路、光学涂层等领域具有巨大的应用潜力。然而,SiO_(2)薄膜制备过程中面临表面粗糙度、杂质控制和致密性等问题。为解决这些问题,研究者们通过工艺改进和表面修饰等手段来提高SiO_(2)薄膜的性能。在众多SiO_(2)薄膜制备技术中,等离子体增强化学气相沉积(Plasma-Enhanced Chemical Vapor Deposition,PECVD)技术由于沉积SiO_(2)薄膜所需温度低、原位生长等优势,成为制备SiO_(2)薄膜最常用的方法。综述了用PECVD技术制备SiO_(2)薄膜的发展历程,并探讨了关键工艺参数和后处理工艺对薄膜质量的影响。对PECVD技术的深入研究,有助于实现对SiO_(2)薄膜生长的更精准控制,进一步拓展其广泛的应用前景。

基于GRA的强夯指标影响因素分析及预估模型建立

为消除强夯法施工控制指标影响因素权重判定过程中,因人为主观因素产生的误差,文中提出以夯击沉降量、有效加固深度及夯击间距作为目标,选取诸如土体参数、夯锤形态及施工工艺等因素作为行为因子,以灰色关联理论建立其间的相互联系,分析各影响因素的关联度。在此基础之上,以多元回归分析为手段,建立控制指标力学-经验模型。结果表明,对于夯击沉降量、有效加固深度及夯击间距而言,需以夯击能、土体重度及夯锤底面积作为主要控制因素;建立的力学-经验模型具有较高的精度,R2均在0.9以上,可为强夯施工初期各项施工工艺、土体参数、施工设备的选择提供理论参照。

路基压实质量检测与评价综述

路基压实质量检测与评价是控制路基压实质量的关键因素。从压实检测指标、压实检测方法的优缺点、压实质量评价方法三个方面,对传统压实质量控制方法与连续压实控制技术进行梳理,并总结连续压实质量控制技术的不足,提出其进一步的研究方向,以促进连续压实控制技术的推广应用。

Real-time compaction quality monitoring of high core rockfill dam

The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by human behavior or lack of adequate management. We therefore establish the timely monitoring indexes and control criteria of compaction processes by considering the characteristics and quality requirements of high core rockffll dam construction. Based on the established indexes and criteria, integrating GPS, GPRS and PDA technologies, a real-time compaction quality monitoring method is proposed. The relevant key techniques are proposed as well, including automatic collection of information and a graphic algorithm for rolling-process visualization. By the proposed method and techniques, a real-time monitoring system is provided to realize the precise automatic online entire-process monitoring of compaction parameters, including compaction pass, rolling trajectory, nmning speed of roller, vibration status and rolled pavement thickness. The application of the Nuozhadu project shows that the proposed system can control compaction parameters effectively and ensure better construction quality. Therefore, it might become a new way towards construction quality control of high core rockfill dam.

Utilizations of Statistics on Optimizing Parameters in Compact Spinning with Pneumatic Groove

The compact spinning with pneumatic groove utilizes transverse air force and mechanical force of the pneumatic groove to condense fiber bundles to eliminate the spinning triangle.Range analysis and variance analysis of orthogonal experiment were used to discover both important and general factors that influence the condensing effect of the compact yarn including negative pressure,traveler,roving moisture regain,and spinning tension.Results from this research have confirmed that the spinning tension is the most important factor affecting the condensing effect and the yarn quality;the negative pressure,traveler,and roving moisture regain are general factors.The optimal combination for producing least yarn hairiness,A3B2C1D1,is acquired,where the value of negative pressure A is -3.0 kPa,roving moisture regain B is 7.64%,traveler C is 20 #(yarn tex 20.8),and spinning tension D is 25 cN.

FREDHOLM AND COMPACT MAPPINGS SHARING A VALUE

Sufficient conditions are given to assert that two differentiable mappings between Banach spaces have common values. The proof is essentially based upon continuation methods.

CDV Index: A Validity Index for Better Clustering Quality Measurement

In this paper, a cluster validity index called CDV index is presented. The CDV index is capable of providing a quality measurement for the goodness of a clustering result for a data set. The CDV index is composed of three major factors, including a statistically calculated external diameter factor, a restorer factor to reduce the effect of data dimension, and a number of clusters related punishment factor. With the calculation of the product of the three factors under various number of clusters settings, the best clustering result for some number of clusters setting is able to be found by searching for the minimum value of CDV curve. In the empirical experiments presented in this research, K-Means clustering method is chosen for its simplicity and execution speed. For the presentation of the effectiveness and superiority of the CDV index in the experiments, several traditional cluster validity indexes were implemented as the control group of experiments, including DI, DBI, ADI, and the most effective PBM index in recent years. The data sets of the experiments are also carefully selected to justify the generalization of CDV index, including three real world data sets and three artificial data sets which are the simulation of real world data distribution. These data sets are all tested to present the superior features of CDV index.

RCC坝料改进刚度指标及压实质量综合评估研究

有效控制碾压混凝土压实质量是确保大坝安全稳定运行的前提。本文提出了考虑滞后相位角的碾压混凝土坝料改进刚度指标,并给出了滞后相位角的测定方法;结合耦合滞后相位角改进刚度指标、坝料特性参数、碾压参数和频域压实指标,提出了基于XGBoost算法的碾压混凝土压实质量综合评估方法。实例分析表明,改进刚度指标能够更好表征坝料压实质量,综合评估模型的决定系数约为0.86,表明模型精度较高,计算压实度与实测压实度的相对误差平均值为0.47%。本文方法为碾压混凝土坝施工压实质量控制提供了新的有效途径。