The relationship between in-treatment abstinence and post-treatment abstinence in a smoking cessation treatment.

Previous research has indicated that abstinence early in a smoking cessation program is predictive of successful posttreatment abstinence. However, it has not been established whether or not this effect is independent of other in-treatment abstinence patterns. In this paper the relationship between three potentially important aspects of in-treatment smoking abstinence and posttreatment smoking abstinence are examined: early abstinence, extended abstinence, and end-of-treatment abstinence. We examined the relationship between smoking behavior measured each weekday over 70 visits (approximately 14 weeks) of a contingency management smoking cessation program and at a follow-up visit 6 months after study entry (3 months after the scheduled end of treatment). Ninety-five of 102 participants were successfully followed-up. Seven of these 95 participants were confirmed abstinent. Early abstinence, defined as abstinence during the first 10 treatment visits, was significantly and independently related to follow-up abstinence (OR = 56.67 [7.29–440.63]). Extended abstinence and end-of-treatment abstinence were related to follow-up abstinence, but not independent of early abstinence based on multiple regression models. Inclusion of a variety of demographic and environmental characteristics did not significantly alter this relationship. Thus, consistent with the previous literature, the establishment of early abstinence appears to be crucial to establishing longer-term abstinence, independent of other in-treatment abstinence patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Accuracy improvement of a multistep splitting method for nonlinear viscous wave equations

This paper focuses on a multistep splitting method for a class of nonlinear viscous equations in two spaces, which uses second-order backward differentiation formula (BDF2) combined with approximation factorization for time integration, and second-order centred difference approximation to second derivatives for spatial discretization. By the discrete energy method, it is shown that this splitting method can attain second-order accuracy in both time and space with respect to the discrete L²- and H¹-norms. Moreover, for improving computational efficiency, we introduce a Richardson extrapolation method and obtain extrapolation solution of order four in both time and space. Numerical experiments illustrate the accuracy and performance of our algorithms.     

用于图像预测编码的预测器的设计及应用

设计并实现了一个用于图像预测编码的预测器。在图像压缩中,预测器是影响整个图像压缩比以及图像质量的关键环节。为了提高预测器的性能,本文结合了线性与非线性预测器的设计方法,首先对图像像素及其邻域像素之间的相关性估计值进行统计计算,确定该预测器的最佳阶数为四阶,接下来以预测差值的最小均方差标准和差值图像的期望值恒为零的约束为前提,同时对邻域模板的平坦程度加以分类,统计分析各类图像得出大量实验数据,最终设计出性能较好的四阶预测器。由于该预测器应用于星载图像的压缩,其预测系数在设计时兼备了便于硬件实现的特点。     

具有比例积分结构的广义预测自校正控制在工业锅炉燃烧系统中的应用

将具有比例积分结构的广义预测自校正控制器应用于链条锅炉燃烧控制系统,通过连续系统仿真,结果表明这种控制器具有较强的适应性和鲁棒性,有较高的控制精度。     

基于Smith预估器的单片机温控系统的实现

用1台单片机及相应的部件组成电阻炉炉温自动控制系统,采用Smith预估器克服系统较大的滞后性,给出了详细的系统结构图和程序流程图.     

空心圆柱试样真三轴仪应力路径的控制

介绍了新研制的空心圆柱试样真三轴仪内外腔加载压力独立控制的机电液光一体化电液伺服加载装置,以及由步进电机独立控制沿试样轴向方向的载荷和为实现主应力旋转在试样端面上施加设定的控制扭矩的加载装置。采用卡尔曼滤波及预报递推控制算法,克服步进电机加载系统与电液伺服加载装置响应速度不一致的问题,从而在连续加载试验中,使尽可能多的离散点遵循设定的加载应力路径。     

Contributions of congruent pitch motion cue to human activity in manual control

The contribution of pitch motion cues to the performance of human pilots in compensatory tracking task are evaluated from pairs of uniquely planned experiments on a motion based research simulator, which allow separation of the visual responses from combined motion-visual responses. Analytical time series human pilot models of the least squares structure are evaluated from the input-output data and the results are discussed in terms of familiar parameters of pilot models and predictor operator. Beneficial contributions of pitch motion cues and subject differences are presented.     

模糊Smith智能温度控制器的设计与仿真

结合模糊PID控制与模糊自适应Smith预估控制的优点,提出了模糊Smith智能控制方法。用模糊控制方法设计了改进型Smith预估器的滤波时间常数,并制定了其整定规则和参数的模糊自适应调整机构。仿真研究表明,模糊Smith智能控制能改善参数时变的纯滞后系统的控制性能,提高系统控制时的鲁棒性与自适应性。     

基于双控制器的一类积分纯滞后系统的研究

针对一类积分加纯滞后系统,在常规Smith预估控制器的基础上采取了一种双控制器结构,实现了系统的目标值跟踪特性和干扰抑制特性分离.这种控制器结构简单,可调参数少,参数的调节方便,直观.仿真结果表明:在干扰和模型失配的情况下,此类控制器仍然具有良好的控制性能和鲁棒稳定性能.     

三容器液位系统Smith预估器设计及其仿真

三容器液位控制系统具有典型的滞后特性,用常规的PID控制难以达到精确的控制效果.本文首先给出了该系统的数学模型, 并应用Smith预估补偿算法进行控制,最后在C Builder中进行了仿真.仿真结果表明Smith预估补偿控制与常规的PID控制相比,具有调节时间短、超调量小、鲁棒性好等优点.