基于时空的弱点状运动目标检测技术

如何在复杂背景下持续有效地检测目标位置,一直是研究者们需要面对的主要挑战。本文在研究红外点状移动目标特征的基础上,根据目标无纹理,无形状的特性,提出一种改进的形态学目标增强算法,并利用目标连续时空不变性检测目标。首先,建立多尺度的图像金字塔,在每层上采用改进的形态学算法快速、粗糙定位小目标。然后进一步的根据目标在时空上的位置相关性,提出基于目标运动特征分析的精确检测方法。得到精确稳定的检测结果。最后实验结果表明与经典的形态学检测算法及其他算法相比,该技术能更有效地检测弱小目标,具有更高的鲁棒性。     

Influences of chip serration on micro-topography of machined surface in high-speed cutting

Saw-tooth chip changes from macroscopically continuous ribbon to separated segments with the increase of cutting speed. The aim of this study is to find the correlations between chip morphology and machined surface micro-topography at different chip serration stages encountered in high speed cutting. High strength alloy steel AerMet100 was employed in orthogonal cutting experiments to obtain chips at different serration stages and corresponding machined surfaces. The chips and machined surfaces obtained were then examined with optical microscope (OM), scanning electron microscope (SEM), and white light interferometer (WLI). The result shows that chip serration causes micro-waves on machined surface, which increases machined surface roughness. However, wave amplitudes (surface roughness) at different serration stages are different. The principal factor influencing wave amplitude is the thickness of the sawed segment (tooth) of saw-tooth chip. With cutting parameters in this study, surface roughness contributed by chip serration ranges from 0.39 μm to 1.85 μm. This may bring on serious problems in the case of trying to replace grinding with high-speed cutting in rough machining. Some suggestions have been proposed to control the chip serration-caused surface roughness in high-speed cutting based on the results of the current study.     

Thermo-physical properties of as deposited and aged thermal barrier coatings (TBC) for gas turbines: State-of-the art and advanced TBCs

In the perspective of fuelling the future generations of gas turbines by hydrogen rich syngas, the evaluation of the effect of a higher water vapour content into the flue gases on the TBC used, or potentially usable, is a need. For this purpose YPSZ APS TBC with two different microstructures have been exposed for 500?h at different temperatures in the range 1000?°C–1250?°C either in air and air +20% vol. H₂O. The comparison between the different testing conditions has been performed in terms of sintering kinetics and phase stability, as evaluated by thermal diffusivity measurements and Synchrotron X-Rays diffraction, respectively. Furthermore the characterisation of thermal properties of two innovative TBCs (GZO-YPSZ and YAG) potentially able to withstand the CMAS attack and erosive environments, respectively, has been carried out.No clear evidence of a different behaviour of TBC has been observed, at least in the considered aging time and temperature range.     

水泥浆失水制约下套管与井眼间隙的研究

通过对水泥浆失水规律的室内试验分析以厦对注水泥顶替过程中水泥浆失水桥堵套管与井眼间隙问题的研究，建立了顶替过程中滤失层不发生水泥浆失水而桥堵环形空间的临界失水量计算模型，提出了调配水泥浆失水性能和确定合理套管井眼间隙的具体方法，对注水泥现场施工和井身结构设计具有一定的指导意义。     

石化企业线性规划模型的自动生成

根据石化企业生产过程的实际情况，考虑原料供应量、装置加工能力、物料平衡和价格等情况．建芷反映企业生产情况的线性规划数学模型。分别阐述了模型的决策变量、目标函数和约束方程的自动生成的方法，并给出了模型文件的存储结构。     

川东气藏直井完井方法的产能预测研究

在分析研究目前国内外油气井完井产能计算经验公式的基础上，针对四川气田东部浅层气藏常用的几种完井方式，建立了该地区完井产能预测的数学模型。通过实例计算，表明了其数学模型的准确可行性，并为出砂井和非出砂井的完井方式提供了选择依据：对于出砂井，砾石裸眼充填完井方式是最理想的完井方式；对于非出砂井，实际裸眼完井的产能最大。得出的结论对该地区直井完井方式的选择，完井参数优化设计以及产能预测具有一定的指导作用。     

天然气产业链下游市场风险评价模型探讨

随着我国天然气主干管网的逐步形成，天然气产业链下游市场正在进入快速成长阶段，建立风险预警系统的重要性开始显现，而风险评价模型是其基础工作之一。文章在天然气产业链下游区域市场风险评价指标体系的基础上，综合运用层次分析法和灰色系统理论，建立了对天然气产业链下游区域市场风险评价的模型，并以各区域市场的用气量占全国总用气量的比重为权重，建立起完整的市场风险评价模型，可为评价天然气产业链下游市场整体市场风险时参考。     

膨胀套管的弹塑性理论分析

分析认为，膨胀套管在膨胀过程中先进入弹性阶段，然后进入弹塑性阶段，最后进入塑性流动阶段。采用弹塑性分析方法，对膨胀套管膨胀过程中套管内壁的受力与变形进行了研究，模拟了其成形的过程，并建立了解析解，为膨胀套管膨胀操作过程中确定关键操作参数提供了理论支持。根据推导出的力学模型，计算出了外径107．9mm、钢级为J55的膨胀套管膨胀到直径139．7mm时膨胀芯头拉头处的轴向力为195．94kN。     

渤海绥中油田J3井疏水缔合聚合物驱数值模拟研究

为了进一步提高渤海油田J3井区缔合聚合物驱的技术经济效果,在渤海油田室内配方和先导性矿场试验研究基础上,利用化学驱油藏数值模拟软件FAPMS,分析和研究了高浓度缔合聚合物前置段塞、主段塞的大小和浓度以及段塞组合方式对驱油效果的影响,优化设计了渤海绥中油田J3井区块矿场试验的最佳注入程序及段塞大小。结果表明,通过对不同浓度的疏水缔合聚合物注入的前置段塞及主段塞和梯度式后续段塞的优化后,原油采收率比未优化时提高了约10个百分点。研究表明,渤海油田应该高度重视聚合物驱的注入方式和段塞优化设计,进一步提高聚合物的技术经济效果。