HDF 5格式特点及其对遥感数据格式标准化的几点启示

阐述了HDF 5数据格式的特点及其对遥感数据标准化的启示和借鉴作用。HDF 5格式层次式的逻辑结构、B树的物理存储方式，面向对象的特性、数据类型的广泛支持、自我描述以及内容与表达的分离等特点，使得它在记录和存储科学数据时具有强大的优势。遥感数据标准化如何设计一种结构简单且扩展性很好，同时支持不同平台的标准格式，可以从HDF 5的实现方法上得到借鉴。     

一种新的运动检测及轮廓追踪方法

构建了基于块区域二阶矩比的三帧差分运动检测模型,应用文献[1]中的核密度估计模型来滤除其中的非运动区域,并采用支持向量聚类实现多目标检测。给出了运动物体轮廓快速追踪的RW算法,该算法不必考虑检测区域内部的细节问题,能够充分利用所检测到的边缘信息,比较符合人眼对轮廓的搜索习惯。最后给出了实验结果。     

海气耦合模式的优化方法研究

气候模式不断发展的同时，对高性能计算机提出了更高的要求，如何提高模式在现有计算机资源上的运行效率问题已越来越重要。文章介绍了利用编译器优化和手工优化技术对海气耦合模式进行优化试验，优化后模式运行效率提高60%，表明将这些优化方法应用到气候模式的改进工作中，可以达到较好的效果。     

非弹性反应谱计算的一个改进算法

本文就非弹性地震反应谱的计算问题（运动方程的形式，谱参量的选取，方程解算中恢复力模型上拐折点的处理和时间积分方法），给出了几点理论考虑，介绍了一个改进的算法。这一算法具有精度好和效率高的优点，这对做好结构抗震设计和其它地震工程问题中需要处理大量强震动数据的分析研究工作是有利的。文中还就双线型恢复力模型具体计算了2个例子（一个为屈服强化情形，另一个为理想弹塑性情形）。最后联系计算工作和计算结果，对非弹性反应谱计算中的其它有关事项做了补充讨论和说明。     

A reassessment of dynamic characteristics of the Quincy Bayview Bridge using output‐only identification techniques

A reassessment of the dynamic characteristics of the 542 m cable‐stayed Bayview Bridge in Quincy, Illinois, is presented using a newly developed output‐only system identification technique. The technique is applied to an extensive set of ambient vibration response data acquired from the bridge in 1987. Vertical, torsional and transverse modal frequencies of the deck are identified, and uncertainty in damping values are estimated using an automated procedure on several redundant measurements at four locations. Important practical implementation issues associated with the implementation of the procedure and selection of algorithm design parameters for stochastic subspace identification techniques are discussed. An overall mean and standard deviation of damping of 1.0±0.8% is estimated considering all identified vertical, torsional and transverse modes in the 0–2 Hz band. The mean damping for the fundamental vertical mode (0.37 Hz) is identified as 1.4±0.5%, and for the first coupled torsion–transverse mode (0.56 Hz) is identified as 1.1±0.8%. Variability in the damping estimates is shown to decrease as estimated modal RMS acceleration levels increase. Standard deviations on estimated damping range from 0.05% to 2%. The results are shown to be a substantial improvement in the evaluation of damping compared to earlier spectral analysis conducted on the same data set. Copyright © 2005 John Wiley & Sons, Ltd.     

A hybrid genetic—instance based learning algorithm for CE-QUAL-W2 calibration

This paper presents a calibration model for CE-QUAL-W2. CE-QUAL-W2 is a two-dimensional (2D) longitudinal/vertical hydrodynamic and water quality model for surface water bodies, modeling eutrophication processes such as temperature–nutrient–algae–dissolved oxygen–organic matter and sediment relationships. The proposed methodology is a combination of a ‘hurdle-race’ and a hybrid Genetic-k-Nearest Neighbor algorithm (GA-kNN). The ‘hurdle race’ is formulated for accepting–rejecting a proposed set of parameters during a CE-QUAL-W2 simulation; the k-Nearest Neighbor algorithm (kNN)—for approximating the objective function response surface; and the Genetic Algorithm (GA)—for linking both. The proposed methodology overcomes the high, non-applicable, computational efforts required if a conventional calibration search technique was used, while retaining the quality of the final calibration results. Base runs and sensitivity analysis are demonstrated on two example applications: a synthetic hypothetical example calibrated for temperature, serving for tuning the GA-kNN parameters; and the Lower Columbia Slough case study in Oregon US calibrated for temperature and dissolved oxygen. The GA-kNN algorithm was found to be robust and reliable, producing similar results to those of a pure GA, while reducing running times and computational efforts significantly, and adding additional insights and flexibilities to the calibration process.     

A Versatile Nonlinear Inversion to Interpret Gravity Anomaly Caused by a Simple Geometrical Structure

A geophysical interpretative method is proposed to depth, amplitude coefficient and geometrical shape factor determination of a buried structure from an observed gravity anomaly related to a cylinder or a sphere-like structure.The method is based on nonlinearly constrained mathematical modelling and also on stochastic optimization approaches. The proposed interpretative method first has been tested on theoretical synthetic models with different random errors at a certain depth, where a very close agreement has been observed between assumed and evaluated parameters. Subsequent field data have been considered for which the interpreted results by other methods are available for comparison. The agreement between the obtained results by the proposed technique and by other geophysical methods is good. A statistical analysis has been also carried out to demonstrate the accuracy and the precision of the suggested interpretative method.     

固体潮观测数据预处理中的一些常用方法

从台站产出的原始地形变前兆数据出发,提出一些实际操作性较强的预处理方法,从已编制好的软件中给出处理实例,从而提高台站观测人员的科研能力,填补资料预处理方面的某些空白,这对于台站人员集观测、科研于一体有着十分重要的意义。从950102项目厦门地震台前兆数据预处理的实践表明:这些方法取得了明显的实效,直到今天仍然具有很大的使用价值。     

Studies on structural vibration control with MR dampers using μGA

A new approach to reducing the seismic response of spatial structures with magneto-theological （MR） dampers is presented in this paper. The Genetic Algorithm with small populations （μGA） is used to optimize the control for the MR dampers to reduce structural vibration, which is difficult to achieve using classical optimal control. The advantages of μGA are the use of global properties and that fewer conditions are required to obtain the optimal function. Numerical results demonstrate the effectiveness of the proposed method in reducing the seismic response of structures.     

一次逼近理论下边坡稳定的模糊随机数值分析

在协调元基础上,通过一次逼近理论,建立随机有限元模型,并通过模糊数学模型实现对边坡体工作状态的软化处理;借助于模糊随机数值方法对荆南长江干堤局部破坏失效进行了较为全面的研究。