Simplified method for analyzing soil slope deformation under cyclic loading

Reasonable assessment of slope deformation under cyclic loading is of great significance for securing the safety of slopes. The observations of centrifuge model tests are analyzed on the slope deformation behavior under cyclic loading conditions. The potential slip surface is the key for slope failure and follows two rules: (i) the relative horizontal displacement along the potential slip surface is invariable at an elevation, and (ii) the soil along the slip surface exhibits the same degradation pattern. These rules are effective regardless of the location of the potential slip surface throughout the entire deformation process of a homogeneous slope, ranging from the initial deformation stage to the failure process and to the post-failure stage. A new, simplified method is proposed by deriving the displacement compatibility equation and unified degradation equation according to the fundamental rules. The method has few parameters that can be determined through traditional element tests. The predictions from the proposed method agree with the centrifuge test results with vertical loading and shaking table loading. This result confirms that the proposed method is effective in predicting the full deformation process of slopes under different cyclic loading conditions.     

相干体分析技术在BST地区的应用

在油气田勘探开发中,断层解释的准确性和合理性直接影响构造成果的精度和开发方案的设计。相干体分析技术是目前解释断层最有效的方法之一,该技术已成为全三维解释流程中的重要组成部分。用相干体分析技术进行断层解释和组合,避免了解释结果的随意性,补充了因解释人员经验所导致的结果不合理性。在进行三维地震资料解释之前使用相干体分析技术,可以有效地落实断层的空间展布情况,避免断层的剖面解释和平面组合的多解性。在BST地区利用相干体分析技术,预测出了该地区的断裂系统分布情况,理清了该地区断裂系统中的小断层和大断裂之间的切割关系,对于指导断裂的平面组合,提高断裂识别的精度具有重要意义。     

The Slice Algorithm for irreducible decomposition of monomial ideals

Irreducible decomposition of monomial ideals has an increasing number of applications from biology to pure math. This paper presents the Slice Algorithm for computing irreducible decompositions, Alexander duals and socles of monomial ideals. The paper includes experiments showing good performance in practice.     

基于协同表示的多特征融合岩石分类

针对传统的岩石薄片成分分析耗时、识别率不高等问题,提出了一种基于协同表示(CR)的岩石薄片成分分析方法。首先,分析探讨了岩石薄片中颗粒纹理特性,证明将薄片图像的分层多尺度局部二值化(HMLBP)特征与灰度共生矩阵(GLCM)特征相融合能有效地表征岩石薄片中颗粒的纹理。然后,为降低识别阶段时间复杂度,采用主成分分析(PCA)方法将新特征降维到100维。最后,采用基于协同表示的分类器(CRC)进行分类识别。与基于稀疏表示的分类器(SRC)分别采用样本字典中某一个样本单独编码表征预测样本不同,基于协同表示的分类器采用样本字典中的所有样本协同编码表征预测样本,借助不同样本的同一属性提高识别率。实验结果表明该方法的识别速度较基于稀疏的分类器识别方法提高300%,识别率提高2%;在实践应用中能较好地区分岩石薄片中的石英成分和长石成分。     

神东矿区特厚煤层合理开采方法的优化选择

分析了特厚煤层分层开采、综放开采、一次采全厚开采3种开采方法对神东矿区特厚煤层的实用性和经济性。结果表明,一次采全高综合机械化开采是较适合神东矿区7m左右特厚煤层的开采方法。补连塔煤矿22303工作面采用了7 m一次采全高综合机械化开采,并取得了良好的经济效益。     

分层开采的切顶房柱法在磨坊矿的应用

磨坊矿结合生产实际,设计采用分层开采的切顶房柱采矿法开采缓倾斜中厚矿体。实践证明,分层开采的切顶房柱采矿法具有损失率低、贫化率低、回采率高、工艺技术简单等优点。     

光学薄片用作检测微小深度敏感元件的研究

本文对光学薄片用作检测微小深度敏感元件的机理进行了研究，得到了敏感元件输出与输入间的关系式，对微精加工中离子束刻蚀深度的传感技术具有现实意义。     

Slice groups for post-compression region of interest encryption in H.264/AVC and its scalable extension

Encrypting regions of interest in H.264/AVC and SVC bit streams after compression is a challenging task due to drift. In this paper, we assess whether the use of slice groups makes this task easier and what its expense in terms of bit rate overhead is. We introduce the concept of all-grey base layers for SVC which simplify the encryption of regions of interest in surveillance camera applications while obeying all standard-imposed base layer restrictions. Furthermore, we show that the use of slice groups is possible with relatively low overhead for medium and high bit rates (below 5% in most of the tested configurations). This applies to H.264/AVC as well as SVC bit streams with two and three spatial layers, including those with the newly introduced all-grey base layers. Although we are able to contain spatial and inter-layer drift with our proposed encryption setup, temporal drift still remains an issue that cannot be solved by sole usage of slice groups.     

聚合物溶液粘度的主要影响因素分析

影响聚合物溶液粘度的外来因素是多方面的,包括pH值、温度、各种金属阳离子、搅拌速度和时间等.对以上诸因素进行了全面的实验分析,并确定了现场配制时应控制的主要指标范围:pH值应控制在6～9,温度以15～30 ℃为宜,并且应当尽量用矿化度较低的清水配制,配制时搅拌速度应控制在150 r/min以下,搅拌时间不应超过50 min.     

A first-order analytical investigation on emittance evolution of relativistic space-charge dominated beams

The evolution of both correlated emittance and slice emittance due to nonlinear space-charge force of relativistic cylindrical beams in a general photoinjector beamline are investigated analytically in first-order approximation and based on envelope analysis, in order to clarify the relation between the evolution of the two kinds of emittance. The first-order analysis shows that slice emittance due to transverse nonlinear space-charge force and correlated emittance have similar behavior in a general photoinjector if energy spread is neglected and phase space wave breaking does not happen. Furthermore, the two kinds of emittance have the same dependence on propagating distance for specific initial-phase space. As another result of the first-order analysis, the evolution of the two kinds of emittance in drift space can be depicted analytically as a function of only the propagating distance and several parameters determined by the initial-phase space. The analytical expressions predict that two emittance compensation points exist when some constraints on the initial-phase space are fulfilled, which may correspond to the well-known double emittance minimum phenomenon often observed in simulations of photoinjectors. Parmela simulations are carried out to verify the analytical results and are in good agreement to the analytical results.