填料萃取塔液泛速度的计算

介绍了三种有代表性的填料萃取塔的液泛速度计算公式，并通过它们用于三种典型的液-液实验体系和两种不同填料的计算结果的比较，对这些公式的适用范围进行了讨论。     

OFA-II型定量荧光仪在油气勘探中的应用

定量荧光仪在现场应用中受到各种因素的影响:如岩屑样品浸泡时的干、湿;图谱是否出现了淬灭;环境温度的影响等等。文章通过具体事例给出解决这些问题的办法。     

Approximate channel identification via δ‐signed correlation

A method of approximate channel identification is proposed that is based on a simplification of the correlation estimator. Despite the numerical simplification (no multiplications or additions are required, only comparisons and an accumulator), the performance of the proposed estimator is not significantly worse than that of the standard correlation estimator. A free (user selectable) parameter moves ‘smoothly’ from a situation with small sum‐squared channel estimation error but hard‐to‐identify channel peaks, to one with a larger sum‐squared estimation error but easy‐to‐identify channel peaks. The proposed estimator is shown to be biased and its behaviour is analysed in a number of situations. Applications of the proposed estimator to sparsity detection, symbol timing recovery and to the initialization of blind equalizers are suggested. Copyright © 2002 John Wiley & Sons, Ltd.     

账面盈利与经营活动现金净流量的相关性研究——基于金属非金属行业上市公司的实证分析

对2004年中国证券市场上的129家金属和非金属行业上市公司的会计账面盈利与现金流量的相关性进行实证研究后,发现两者的相关程度很低,很大一部分上市公司的账面盈利没有形成相应的现金流入,导致两者之间产生“滞脱”的效应.因此,笔者认为在对企业的财务状况进行评价时,不能仅仅局限于使用一些反映企业账面盈利的指标,应该还需要考虑一些反映企业创造现金流量能力的指标.     

注入剖面双相态放射性测井方法研究

文章结合注入剖面同位素示踪和放射性相关流量两种测井方法的特点,提出了固态微球同位素和液态同位素同时使用的综合测井方法.应用放射性相关流量测井的直观性,量化同位素示踪测井中的不确定因素,达到提高测井成功率和资料解释精度的目的.     

A digital secure image communication scheme based on the chaotic Chebyshev map

In this paper, a simple image secure communication scheme based on the chaotic Chebyshev map and chaos synchronization is proposed. The scheme relies on the excellent correlation property of chaotic sequences, which is very desirable for secure image communication. The results obtained by computer simulation indicate that the transmitted source image can be correctly and reliably recovered using the proposed scheme, even through a noisy channel. Notably, the scheme possesses relatively high security and can be easily implemented. Moreover, the quality of the recovered image is satisfactory, quantified by such common criteria as the bit‐error rate performance. Copyright © 2004 John Wiley & Sons, Ltd.     

基于数学形态学的红外图像小目标检测

针对红外成像跟踪系统的低信噪比、背景和噪声干扰严重的小目标图像,以及后续的目标识别处理需要目标的灰度信息的特点,设计了一种基于数学形态学的红外灰度图像小目标检测算法,并用FPGA硬件实现。实验表明,数学形态学滤波能够大大提高目标的信噪比,去除背景和噪声干扰,保留目标的灰度信息,满足系统实时性要求,是一种有效的红外灰度图像小目标检测算法。     

跳时序列与跳频序列的性能比较

通过对传统通信中跳频序列与超宽带无线电通信中跳时序列的分析比较,得出了两者间相关性能的关系,论述了两者之间的差异,并总结出了将跳频序列转换成为跳时序列的方法,从而为超宽带无线电通信中跳时序列的构造提供了参考。     

Distinctiveness and Correlation in Conceptual Structure: Behavioral and Computational Studies.

Patients with category-specific deficits have motivated a range of hypotheses about the structure of the conceptual system. One class of models claims that apparent category dissociations emerge from the internal structure of concepts rather than fractionation of the system into separate substores. This account claims that distinctive properties of concepts in the living domain are vulnerable because of their weak correlation with other features. Given the assumption that mutual activation among correlated properties produces faster activation in the normal system, the authors predicted a disadvantage for the distinctive features of living things for unimpaired adults. Results of a speeded feature verification study supported this prediction, as did a computational simulation in which networks mapped from orthography to semantics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A simple correlation for gas bubbles rising in power‐law fluids

Recently, the author (Rodrigue, 2001 a, b) proposed a generalized correlation for the steady rise of gas bubbles in uncontaminated viscous Newtonian fluids of infinite extent. It is the purpose of this note to show that this model can be modified for inelastic non‐Newtonian power‐law fluids. Using data taken from six different studies, it is shown that the modified model can predict quite nicely the bubble velocity for these non‐Newtonian inelastic fluids.