变权组合预测模型在大坝安全监测中的应用

简要介绍了组合预测模型的基本原理，该模型改进了单一模型考虑因素的片面性，但常规的组合预测模型的权系数是固定的。考虑到各种模型的预测精度的变化，以及大坝安全监测数据存在的突变、时效等因素，固定权系数的组合预测模型有待进一步改进。文中提出了变权系数组合预测模型，并将其用于实际的大坝安全监测工程。结果表明，变权组合预测模型的预报精度高于其他模型。是一种值得推广的方法。     

A new curvature technique calculation for surface tension contribution in PLIC-VOF method

The volume of fluid (VOF) methods have been used for numerous numerical simulations. Among these techniques used to define the moving interface, the piecewise linear interface reconstruction (PLIC-VOF) is one of the most accurate. A study of the superficial tension impact on two-phase flow with free surface is presented. A new method based on direct staggered grid is developped to include surface tension in PLIC-VOF. The new numerical curvature calculation method doesn't need smoothed colour function and leads to less “spurious current”. This technique is applied to the calculus of surface tension force in the case of the rise of air bubble in viscous liquid and the fall of liquid drop in the same liquid on free surface. Droplets, thin layer and capillarity waves are observed after the free surface rupture for different Bond number. The influence of surface tension calculus is then obvioused and when the drop hit the free surface, wavelets propagate toward the virtual boundaries imposed.     

The analysis of solvation in ionic liquids and organic solvents using the Abraham linear free energy relationship

The contentions made in an earlier paper [J Chem Technol Biotechnol 80 : 133–137 (2005)] that the coefficients of the Abraham solvation equation do not provide meaningful information on the molecular properties of ionic liquid solvents is refuted. The objections noted in the earlier paper disappear when the solvation equation model is correctly applied to the experimental data. It is further shown that the coefficients of the Abraham solvation equations can be used to characterize ionic liquids and can be used to select solvents for the solubility of gaseous solutes. Copyright © 2006 Society of Chemical Industry     

HRP-12型负载杂多酸催化剂的失活原因及预防措施

采用XRD、NMR、IR、MS等手段对长链烷基苯合成中失活负载型杂多酸催化剂进行了表征,结果表明,催化剂的失活主要是由于表面结焦引起的,原料中的双烯、烷基芳烃杂质以及反应生成的副产物重烷基苯是引起催化剂结焦的主要原因,对原料进行脱双烯和脱芳烃精制、提高苯烯比以及用苯洗涤催化剂等措施能够有效抑制催化剂的失活。     

Decomposition of Time Series Dynamic Linear Models

This paper derives the admissible decompositions for a time series dynamic linear model, assuming only that the model is observable. The decompositions depend on factorizations of the characteristic polynomial of the state evolution matrix G into relatively prime factors. This generalizes the method of West (1997 ) which considers one decomposition in the particular case where G is diagonalizable. Conditions are derived for a decomposition to be independent. These results show that no autoregressive process of order d has an independent decomposition for any integer d . Two illustrations of this procedure are discussed in detail.     

Dynamics of Balancing Space and Time in Memory: Tau and Kappa Effects Revisited.

In 3 experiments, the authors studied the organization of spatiotemporal information in memory. Stimuli consisted of configurations of dots, presented sequentially. The stimuli were either proportional, with interdot distances corresponding to interdot durations, or not proportional, with interdol distances not corresponding to interdot durations. After a learning phase, participants reproduced the spatial (Experiment 1), temporal (Experiment 2), or spatial and temporal (Experiment 3) characteristics of the target 60 times in succession. In the nonproportional conditions, effects of variable interdot durations or distances on the reproduction of, respectively, constant distances (tau effect) or durations (kappa effect) were observed, whereas no such effects were observed when variable distances or durations were to be produced. Tau and kappa effects influenced the accuracy but not the variability of responses. The results are discussed in light of the distinction between properties of the stabilized mental image and the process of stabilization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fixed point theorems on fuzzy normed linear spaces

In this paper, definitions of strongly fuzzy convergent sequence, l-fuzzy weakly convergent sequence and l-fuzzy weakly compact set are given in a fuzzy normed linear space. The concepts of fuzzy normal structure, fuzzy non-expansive mapping, uniformly convex fuzzy normed linear space are introduced and fixed point theorems for fuzzy non-expansive mappings are proved.     

轮式工程机械轮边减速器优化模型与方法

论述了重构轮式工程机械轮边减速器优化设计数学模型的必要性,给出了精确化的目标函数,全面化和准确化的设计变量、基于并行设计的约束条件;介绍了对优化解适用性评价的方法和手段。巧妙地解决了优化解中离散变量的圆整问题,提供了基于MATLAB的求解反渐开线函数的M文件。     

自适应相干噪声衰减技术

去除噪声是必需的地震数据处理过程。由于地表条件和地震波激发、传播以及接收条件等诸多方面的原因，时常引起地震记录上出现各种相干干扰波。本文主要针对地震数据处理中地震剖面上存在的各种相干噪声，提出了时问一空间域自适应相干噪声衰减技术，以进行信噪分离。这种方法把噪声在整个处理平面上的视速度近似看作常量(正值或负值)，可以有效地消除地震剖面上的线性噪声、面波以及多次波等，并且对信号的保真度高。本文方法是复杂地区低信噪比地震数据处理的一种理想的噪声去除方法，具有运算速度快、压制噪声效果好等优点。     

小议变动成本法的合理性

企业对盈亏临界点的计算通常是以变动成本法为基础，但也有以制造成本法为计算基础的，对于这两种成本方法计算的几种盈亏临界点的情况，本文结合案例，通过比较分析认为：盈亏临界点的计算应当以变动成本法为基础更为合理。