基于线性四叉树的快速邻域查询算法

邻域查询是位置服务系统的核心技术,它的实现取决于空间对象数据模型.根据空间对象分布构建的四叉树模型,以及线性四叉树中位置码的使用,提出了一种新的基于线性四叉树的快速邻域查询算法.该算法根据满四叉树结点编码思想对线性四叉树的Morton码进行了改进,并增加了表示四叉树所有结点状态的序列,通过网格模型的邻域查询算法实现了线性四叉树的快速邻域查询.     

一种新的变步长频域块LMS算法

针对现有直接序列扩频（DSSS）通信抗干扰系统中的传统频域块最小均方误差（FBLMS）算法在收敛速度和稳态误差之间存在矛盾的问题,提出了一种新的变步长算法--VSS-FBLMS算法,该算法通过输出信号中剩余干扰所占整体噪声信号的比例来调节变步长因子,步长因子随着干扰的被滤除而逐渐减小,使得DSSS通信抗干扰系统获得更好的抑制干扰效果。首先对传统FBLMS算法的DSSS抗干扰系统进行了介绍,然后对提出的VSS-FBLMS算法进行分析,最后将新算法和传统算法加入DSSS通信抗干扰系统中进行仿真对比。理论分析和仿真结果表明,VSS-FBLMS算法不仅可以有效滤除窄带干扰,而且抗干扰性能优于传统FBLMS算法,收敛速率和稳态误差也都优于传统FBLMS算法。     

Modeling the effect of water, excavation sequence and rock reinforcement with discontinuous deformation analysis

A powerful numerical method that can be used for modeling rock-structure interaction is the discontinuous deformation analysis (DDA) method developed by Shi in 1988. In this method, rock masses are treated as systems of finite and deformable blocks. Large rock mass deformations and block movements are allowed. Although various extensions of the DDA method have been proposed in the literature, the method is not capable of modeling water-block interaction, sequential loading or unloading and rock reinforcement; three features that are needed when modeling surface or underground excavation in fractured rock. This paper presents three new extensions to the DDA method. The extensions consist of hydro-mechanical coupling between rock blocks and steady water flow in fractures, sequential loading or unloading, and rock reinforcement by rockbolts, shotcrete or concrete lining. Examples of application of the DDA method with the new extensions are presented. Simulations of the underground excavation of the ‘Unju Tunnel’ in Korea were carried out to evaluate the influence of fracture flow, excavation sequence and reinforcement on the tunnel stability. The results of the present study indicate that fracture flow and improper selection of excavation sequence could have a destabilizing effect on the tunnel stability. On the other hand, reinforcement by rockbolts and shotcrete can stabilize the tunnel. It is found that, in general, the DDA program with the three new extensions can now be used as a practical tool in the design of underground structures. In particular, phases of construction (excavation, reinforcement) can now be simulated more realistically. However, the method is limited to solving two-dimensional problems.     

哈山地区白垩系沉积相研究

哈拉阿拉特山地区位于准噶尔盆地西北缘前陆褶皱冲断带上,油气资源丰富,但目前的研究中尚缺乏明确的沉积相划分。本文对白垩系底部开展沉积相研究,明确了哈山白垩系地层及砂体平面展布规律。对哈拉阿拉特山地区进一步的油气勘探活动具有一定的指导和借鉴意义。     

A simple example of an indirect estimator with discontinuous limit theory in the MA(1) model

Indirect estimators usually emerge from two‐step optimization procedures. Each step in such a procedure may induce complexities in the asymptotic theory of the estimator. In this note, we are occupied with a simple example in which the estimator defined by the inversion of the binding function has a ‘discontinuous’ limit theory even in cases where the auxiliary one does not. This example lives in the framework of estimation of the MA (1) parameter. The ‘discontinuities’ involve the dependence of the rate of convergence on the parameter, the non‐continuity of the limit distribution w.r.t. the parameter and the estimator's non‐regularity. We are also occupied with a more complex example where the discontinuities occur because of complexities induced in any step of the defining procedure. We present some Monte Carlo evidence on the quality of the approximations from the limit distributions. Copyright © 2014 Wiley Publishing Ltd     

震积岩的特征、成因与浊积岩比较

震积岩是在地层中具有古地震事件纪录的一类岩石的总称。震积岩和浊积岩都是属于事件性沉积范畴,其起因于一定的触发机制,阵发性因素直接或间接诱发下而形成。震积岩是由地震作用所产生的具有震积构造和震积岩序列的灾变事件沉积的。广义上说浊积岩就是由浊流沉积作用而形成的岩石组合。认清震积岩与浊积岩两者之间的相互区别和联系,这对于油气勘探也是很有指导意义的。     

表格式程序设计方法在600MW汽轮发电机组顺序控制装置中的应用

介绍一种以汇编语言为基础的顺序控制装置的软件体系及其设计思想 ,其优点是占用的存储容量小 ,软件的运行速度快。它采用 MC6 80 0汇编语言编制系统软件 ,采用表格式的程序设计方法开发应用软件。文中还介绍了系统软件的基本任务与中断服务程序的设计 ,给出了各种应用模块服务请求及其调度方法的详细描述     

Identification of certain noisy MA models: new results

In this paper, we address the identification problem of p-inputs q-outputs MA models, corrupted by a white noise with unknown covariance matrix, in the case where p<q. Under certain additional conditions, we show that the generating function of the MA model is identifiable (up to a p×p constant orthogonal matrix) from the autocovariance function of the observation. Our results extend those already obtained in Desbouvries et al. [5] and Desbouvries and Loubaton [6].     

层序约束储层预测技术在岩性油藏勘探中的应用

与常规构造油气藏相比,岩性地层油气藏具有更大的隐蔽性,成藏规律更复杂,勘探难度更大,对储层预测等技术的精度要求更高。岩性地层油气藏勘探有效配套的技术,尚处于探索阶段。结合地质和构造特征以及岩性油气藏的发育特点,着重用地球物理的方法来完善和精细化层序地层的划分,对储层进行预测,进而使岩性圈闭的预测精度得以提高。高精度层序地层学及高分辨率地震技术,特别是层序地层学与地震的有效结合,按照沉积背景分析、层序地层划分、小断层精细研究、储层反演、地震相分析、有利区带预测的步骤,在层序约束的等时格架内,重点应用波形分类地震相分析和储层反演特别是特征曲线重构反演来解决平面相识别及垂向分辨率问题,对岩性油气藏认识具有较为明显的效果。文章从我国岩性油气藏勘探的技术需求出发,紧紧围绕岩性油气藏勘探中层序地层学应用和储层预测两大核心内容,提出了一种适合于岩性油气藏勘探的配套技术。     

A multiple-sequence variant of the multiple-baseline design: A strategy for analysis of sequence effects and treatment comparison.

The design logic and potential uses of a variant of the multiple-baseline design that implements multiple treatment sequences is described. The multiple-baseline multiple-sequence (MBL-MS) consists of 2 or more multiple-baseline designs that are interlaced with one another and include all possible sequences of the treatments. The counterbalanced sequencing of treatments permits observation of any sequence effects that are present. This sequencing can permit identification of an optimal treatment sequence and comparison of relative efficacy of treatments. This variation of the multiple baseline also extends the available treatment comparison designs by providing an additional design that does not require reversal or treatment or sequence effects. Because of vulnerability to ceiling and floor effects, the MBL-MS design appears to be primarily useful for the comparison of treatments that take several sessions to produce an optimal level of responding or when the behavior is not subject to floor or ceiling effects. (PsycINFO Database Record (c) 2011 APA, all rights reserved)