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为了更好地评价南堡凹陷页岩油气资源潜力,综合运用地质、地球物理资料,通过岩心及薄片观察、扫描电镜观察、X衍射矿物分析等实验方法,对南堡凹陷泥页岩储层孔裂隙特征及影响因素进行了研究。研究表明,泥页岩储层发育的裂缝分为四种类型:构造缝、异常压力缝、成岩收缩缝和层间微裂缝,其中以高角度构造裂缝为主。孔隙结构复杂,组合形式多样,孔隙类型包括:有机质孔隙、粒间孔、粒内孔。影响泥岩裂缝形成的机制主要有四个方面,即沉积作用、构造运动、地层超压和成岩作用。其中构造运动控制裂缝的发育数量和展布,是南堡1号、2号和5号构造带以及高柳地区泥页岩裂缝发育的主控因素。 相似文献
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为提升变电站巡检机器人的导航避障能力,将深度学习技术应用于变电站场景识别中,提出了一种基于深度卷积神经网络的避障方法.该方法联合图像分类和语义分割两个分支来共同辅助机器人导航避障,分类分支通过获取图像全局信息,保证机器人正确行驶方向;而语义分割支路则根据图像局部信息以及机器人前方目标类别,指导机器人准确避障.实验结果表明,避障方法可以高效地对图像进行分类和分割,同时,在实际变电站环境中,该方法也能为巡检机器人提供有效的避障信息,实现实时自主避障. 相似文献
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HongYu Xiao HongAn Ma Yu Tian Rui Li ShangSheng Li LiQiu Ma Yong Li XiaoPeng Jia 《科学通报(英文版)》2010,55(1):7-10
High-quality type-Ib tower-shape diamond single crystals were synthesized in cubic anvil high pressure apparatus (SPD-6×1200) at 5.4 GPa and 1250-1450°C. The (100) face of seed crystal was used as the growth face, and FeNiMnCo alloy was used as the solvent/catalyst. Two kinds of carbon diffusing fields (type-B and type-G) were simulated by finite element method (FEM). Using the two kinds of carbon diffusing fields, many diamond single crystals were synthesized. The effects of carbon diffusing fields on the ... 相似文献
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The boron-doped type-Ib gem diamond crystals were synthesized successfully by adding amorphous boron into a system of graphite and Kovar catalyst under high pressure and high temperature (HPHT).The effect of additive boron on type-Ib gem diamond was extensively studied including the growth characteristic,morphology and nitrogen concentration.The synthesized boron-doped type-Ib gem diamond crystals were characterized by optical microscope (OM),scanning electron microscope (SEM) and infrared spectrometer (IR)... 相似文献
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The cross-efficiency evaluation method is reviewed which is developed as a date envelopment analysis (DEA) extensive tool.The cross-efficiency evaluation method is utilized to identify the decision making unit (DMU) with the best practice and to rank the DMUs by their respective cross-efficiency scores.The main drawbacks of the cross-efficiency evaluation method when the ultimate average cross-efficiency scores are used to evaluate and rank the DMUs are also pointed out.With the research gap,an improved technique for order preference by similarity to ideal solution (TOPSIS) is introduced to rank the cross-efficiency by eliminating the average assumption.Finally,an empirical example is illustrated to examine the validity of the proposed method. 相似文献
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A novel neural network based on iterated unscented Kalman filter (IUKF) algorithm is established to model and com- pensate for the fiber optic gyro (FOG) bias drift caused by temperature. In the network, FOG temperature and its gradient are set as input and the FOG bias drift is set as the expected output. A 2-5-1 network trained with IUKF algorithm is established. The IUKF algorithm is developed on the basis of the unscented Kalman filter (UKF). The weight and bias vectors of the hidden layer are set as the state of the UKF and its process and measurement equations are deduced according to the network architecture. To solve the unavoidable estimation deviation of the mean and covariance of the states in the UKF algorithm, iterative computation is introduced into the UKF after the measurement update. While the measure- ment noise R is extended into the state vectors before iteration in order to meet the statistic orthogonality of estimate and mea- surement noise. The IUKF algorithm can provide the optimized estimation for the neural network because of its state expansion and iteration. Temperature rise (-20-20℃) and drop (70-20℃) tests for FOG are carried out in an attemperator. The temperature drift model is built with neural network, and it is trained respectively with BP, UKF and IUKF algorithms. The results prove that the proposed model has higher precision compared with the back- propagation (BP) and UKF network models. 相似文献
39.
We demonstrated a two-dimensional quasi-crystal dendritic structure model with negative permeability. The microwave transmission and reflection properties of periodic and quasi-crystal dendritic structure mediums with varied angle incidence were measured. The results showed that the resonant peaks of quasi-crystal negative permeability samples and left-handed samples had tiny shift with the altering of incident angle. Because of the influence of coupling between quasi-crystal dendritic cells, the resonance of the entire material was enhanced or weakened. The quasi-crystal dendritic structure model will provide an easy method to design isotropic left-handed materials (LHMs). 相似文献
40.
采用水热法在不锈钢基底上制备WO3纳米片阵列,然后将其浸渍于不同浓度Zn(NO_3)_2溶液中以负载ZnO纳米颗粒,从而制备出ZnO/WO_3纳米片薄膜。采用场发射扫描电镜(FESEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外-可见吸收光谱(UV-Vis)和电化学阻抗图谱(EIS)等方法对ZnO/WO_3复合薄膜的形貌、结构、物相组成和光电性能等进行分析,重点考察了薄膜电极对亚甲基蓝(MB)的光电催化降解性能。结果表明,WO_3纳米片均匀垂直于基底生长,Zn元素以ZnO颗粒的形式分布在WO_3表面;ZnO的引入促进了WO_3中产生的光生电子-空穴对的分离,从而使ZnO/WO_3复合薄膜表现出比纯WO_3薄膜更优异的光电性能和光电催化活性;在Zn(NO_3)_2浸渍液浓度为20mmol/L时,所制ZnO/WO_3复合薄膜具有最佳的光电催化性能,在MB溶液初始浓度为10mg/L、外加偏压为0.8V、光照1h的条件下,采用该样品对MB的降解率达96.5%,并且复合薄膜具有良好的循环稳定性,在重复使用5次后,对MB的光电催化降解效率没有明显降低,有望在实际污水处理中得到应用。 相似文献