Analytical Model of Surge Flow in Nonprismatic Permeable Channels and Its Application in Arid Regions

A surge running down a dry wadi bed as a consequence of a controlled water release from a reservoir—e.g., for artificial groundwater recharge—represents a free boundary problem. After some time, when aiming for groundwater recharge, the infiltration equals inflow and thus forms a kind of “standing” wave. The numerical solution of such phenomena generally involves considerable problems. For avoiding the numerical inconvenience resulting from the complex interacting surface/subsurface flow, we present an analytical solution of the slightly modified zero-inertia (ZI) equations. The development introduces a momentum-representative cross section for portraying the transient development of momentum and refers to a channel with constant slope, irregular geometry, and a permeable channel bed with significant infiltration. Due to the structure of the solution, any arbitrary infiltration model can be used for quantifying the infiltration losses. For both synthetic prismatic and nonprismatic test channels, the robust and easy-to-use analytical ZI model shows an excellent match with the results of a comparative numerical simulation. Finally, the ZI model is employed for simulating a surge flow downstream of the Wadi Ahin groundwater recharge dam (Oman), in order to perform a scenario for artificial groundwater recharge in a natural wadi channel reach. This realistic application illustrates the potential of the new approach by even computing an almost standing wave and shows its applicability for an accurate and robust evaluation of release strategies.     

基于支持向量回归的时间序列预测

该文简要介绍了时间序列预测的研究状况以及支持向量回归的基本原理,将支持向量回归用于对Box-Jenkins煤气炉时间序列的预测,并同其他前馈网络——BP神经网络、自适应特征空间扩张神经网络进行比较,仿真结果表明,BP神经网络和自适应特征空间扩张神经网络在预测性能上比较接近,而支持向量回归在预测性能方面明显优于这两种方法,为进行模型辨识与建模研究奠定基础.文章最后分析了支持向量回归优于BP神经网络和自适应特征空间扩张神经网络的机理.     

模糊聚类模型用于水文地质条件分析的研究

鉴于人们在进行地下水化学成分分析时通常采用的是传统的定性分析方法这一事实，将陈守煜模糊聚类理论与模型应用于水文地质条件定量化分析的探索。这种方法在理论上能比较全面、真实地反映地下水的客观实际；同时，该方法在邯邢铁矿田的水文地质条件分析中得到了较好的应用     

铜头拱坝位移优化反分析及稳定安全性预测

以铜头拱坝为例，应用确定性力学模型来分析大坝的位移监测资料，将优化反分析技术引入到大坝的运行监控中；并且提出了坝肩点安全度连通率的方法，对大坝的稳定安全性进行了预测。     

BANDWIDTH SELECTION IN KERNEL SMOOTHING OF TIME SERIES

Abstract. The kernel smoothing method has been considered as a useful tool for identification and prediction in time series models. In practice this method is to be tuned by a smoothing parameter. For selection of the smoothing parameter, Härdle and Vieu (Kernel regression smoothing of time series. J. Time Ser. Anal. 13(1992), 209–32) considered a cross-validation rule and proved its asymptotic optimality. In this paper we strengthen their result for a wider use of the kernel smoothing of time series.     

Predicting the handlability of a coal blend from measurements on the source coals

Coals may be blended at mines to meet contractual criteria set by the client. In formulating a blend, the criterion that is hardest to meet is often the handlability because it is difficult to predict. Most research on coal handling treats coal handlability as a property to be measured for a given material, and there appear to have been very few attempts to predict the consequences of blending choices, or to use such information to optimise coal blends for the different contractual requirements. This paper presents what is believed to be the first study to explore the causal relationships in coal blending, to use these to predict the handlability of a blend, and to establish the basis needed to optimise blending choices. The ultimate goal of this work is an algorithm that can be used in on-line real time choices in coal blending operations, either at mines or at power stations.     

精确延时爆破振动速度峰值预测模型

根据几何地震学的基本原理,以单孔爆破振动速度峰值为基础,按照毫秒延时时间间隔建立精确延时逐孔起爆振动峰值预测模型。不仅可以预测爆破振动速度峰值,而且能够直观地展现爆破区域范围内振动峰值的变化情况,并能从保护区域内振动峰值出发,设定合理的毫秒延时间隔时间。根据现场应用数码电子雷管的深孔爆破实验,该方法计算的预测振动峰值与实测振动峰值吻合良好,计算结果可靠性较好,可以在实际工程中推广使用。     

一种广义水驱特征曲线

广义水驱特征曲线对应油田开发过程中多种含水率（ｆｗ）与可采储量采出程度（Ｒ）关系，使其表达式简单、参数容易求解且适用性很强，这是研究者追求的目标。经推导，提出一种新的广义水驱特征曲线：ｌｇＮｐ＝ａ－ｂｌｇ（Ｌｐ／Ｗｐ）（Ｎｐ为累积产油量，Ｌｐ为累积产液量，Ｗｐ为累积产水量）。选取代表３种含水上升类型的老油田（任丘油田、羊三木油田和濮城油田沙一段油藏）的实际数据，分别代入该式，回归得其相应系数ａ、ｂ，即可确定各自ｆｗ与Ｒ的关系，计算所得预测曲线与实际资料吻合得相当好。图３表１参３（王孝陵摘）     

静北潜山油藏小断层模拟

小断层指不能据地震资料辨识的断层，其垂直断距为３０～５０ｍ。小断层的存在对地下流体流动影响很大，在油田勘探和开发中，预测小断层是一大难题。小断层预测包括小断层数预测和其空间位置预测，预测基础是断层的分形性（表现在型式和总体分布方面）。断层的规模可相差很大，但在同一构造应力场中形成的断层群的分布型式很相似；在以断层长度或垂直断距为分析对象时，个体频率在一定范围内呈现出幂律分布特征，且断层长度与垂直断距间亦有幂律关系。据此，认为断层总体幂律在由岩心尺度到地震精度所能辨识的断层尺度范围基本不变，因而可以由已知断层总体幂律来预测小断层数，再用已知断层的产状分布和密度分布来预测小断层的产状和空间位置。以辽河坳陷静北潜山油藏的小断层模拟预测为例，说明本模拟方法。图４参１２（王孝陵摘）     

克拉玛依油田二中区北部油藏数值模拟研究

在水驱数值模拟研究的基础上，讨论了在高含水期继续水驱初始条件的确定；根据试验区新钻的１３口井的最新资料，结合油藏工程的其他方法，将模拟模型校正后，使其最大限度地接近现时油藏，进而建立继续水驱模型进行高含水阶段的动态史跟踪拟合研究；并以此为基础进行配产配注及开发方式的各种设计计算，优选出继续水驱最佳方案，该模拟研究对高含水期油田注水开发具一定的指导意义。