基于参考模型的自适应话音处理

本文讨论了一种带有参考通道的自适应话音消噪滤波器原理，该滤波器采用最小均方差(心幅)算法。将此滤波器应用于复杂噪音背景的话音信号提取，能很好地抑制背景噪声，从而获得清晰的话音信号。     

Simultaneous HPLC quantification of total cholesterol,tocopherols and β-carotene in Barrosã-PDO veal

A simple, rapid and sensitive procedure for the simultaneous determination of total cholesterol, tocopherols and β-carotene in meat is described. The method involves a direct saponification of the meat, a single n-hexane extraction and the analysis of the extracted compounds by normal-phase HPLC, using fluorescence (tocopherols) and UV–Vis photodiode array (cholesterol and β-carotene) detections in tandem. Rates of recovery of spiked meat samples were 93% for cholesterol, 83–86% for (α-, β- and -γ) tocopherols and 89% for β-carotene. Repeatabilities were high (CV < 6%) for all determined compounds, except for δ-tocopherol. This tocopherol, which is not usually present in meat, showed a much lower recovery percentage (73%) and repeatability (12.8%). This methodology was applied for the quantification of total cholesterol, tocopherols and β-carotene in three muscles (longissimus thoracis, longissimus lumborum and semitendinosus) of the Portuguese traditional Barrosã-PDO veal, obtained from autochthonous calves fed extensively during summer (with the least abundant green pastures) and slaughtered in early autumn (October). Barrosã-PDO veal showed median contents of total cholesterol (0.50–0.56 mg/g) and, depending on the analysed muscle, moderate to high contents of α-tocopherol (3.3–3.9 μg/g) and β-carotene (0.07–0.09 μg/g), suggesting an high sensorial and hygienic quality.     

影响水利工程投资变化的实证分析

影响水利工程投资变化的因素可以分为市场因素、经济因素、设计因素、工期因素、不可预见因素等。选用南水北调东线江苏某段工程的投资变化数据,运用多元方差分析的方法就影响因素对不同工程投资变化的影响进行实证分析。结果表明,影响因素对不同工程的投资变化影响存在显著性差异,工程规模越大影响因素的影响程度就越大。据此提出在水利工程投资控制中必须优化价差管理方法,加强设计管理,减少设计变更,建立“静态投资、动态管理”体系来实现对工程投资变化的控制。     

一种PN码自适应捕获门限的改进算法

文献[1]提出了一种用于直扩系统的PN码自适应门限算法。但该文献也指出,此算法对门限总数十分敏感。当门限总数设置不当时,系统的平均捕获时间将显著增加。这限制了该算法在实际中的应用。本文就此提出了改进,给出了算法及电路框图。仿真结果表明,与原方案相比,改进算法改善了对门限总数的敏感性,降低了PN码平均捕获时间。     

On the Locus of Speed-Accuracy Trade-Off in Reaction Time: Inferences From the Lateralized Readiness Potential.

Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporal and spatial aspects of an environmental stimulus influence the dynamics of behavioral regulation of the Aplysia siphon-withdrawal response.

Exposure to turbulence, an environmental stimulus, produces behavioral adaptation in the Aplysia siphon-withdrawal response (SWR). The authors show that the duration and spatial extent of turbulence influence adaptation recovery. In terms of duration, recovery in whole animals and reduced preparations (tail, siphon, and CNS) was more rapid after longer exposures to turbulence (10 min) than after briefer exposures (10 s-5 min). In terms of spatial extent, recovery in reduced preparations was more rapid after diffuse turbulence (tail and siphon together) compared with focal turbulence (siphon alone). Furthermore, spatial extent and duration interact: Duration regulates recovery only when turbulence is diffuse. Results suggest that SWR adaptation reflects a composite of cellular processes, including short-term synaptic enhancement in L30 inhibitory interneurons. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

低渗透储集层中油水层的地球化学综合判识——以济阳坳陷基山砂岩体为例

为了提高低渗透油藏油、水层识别的准确性，以济阳坳陷惠民凹陷基山砂岩体低渗透油藏为研究对象，探索以地球化学方法综合判识储集层流体性质的方法。以试油数据为参考，首先以热解定量方法初步评价，油层与油水同层、油水同层与水层的ST界限分别定为4．00mg／g及2．00mg／g；再以热解色谱定性方法将水层（或干层）与油层及油水同层明确区分；仍不能有效区分的油层及油水同层，则辅以热解参数表征的储集层变异系数进一步评价，变异系数高于0．3的为油水同层，低于0．3的为油层。具单一油源的多口井，可借助菲与二苯并噻吩（P／DBT）将油层及油水同层准确识别，P／DBT值大于12．5则为油层、小于等于12．5则为油水同层。对于相变较快，泥质薄层较多的低渗透油藏，利用热解参数S1／S2可评价储集层的真假隔层及油柱的纵向连通性。图4参17     

Composite scale modeling in the presence of censored data

A composite scale modeling approach can be used to combine several scales or variables into a single scale or variable. A typical application is to combine age and usage together to form a composite timescale model. The combined scale is expected to have better failure prediction capability than individual scales. Two typical models are the linear and multiplicative models. Their parameters are determined by minimizing the sample coefficient of variation of the composite scale. The minimum coefficient of variation is hard to apply in the presence of censored data. Another open issue is how to identify key variables when a number of variables are combined. This paper develops methods to handle these two issues. A numerical example is also included to illustrate the proposed methods.     

Adaptive tracking control of manipulators: Theory and experiments

This paper considers the trajectory tracking problem for uncertain robot manipulators and proposes two adaptive controllers as solutions to this problem. The first controller is derived under the assumption that the manipulator state is measurable, while the second strategy is developed for those applications in which only position measurements are available. The adaptive schemes are very general and computationally efficient since they do not require knowledge of either the mathematical model or the parameter values of the manipulator dynamics, and are implemented without calculation of the robot inverse dynamics or inverse kinematic transformation. It is shown that the control strategies ensure uniform boundedness of all signals in the presence of bounded disturbances, and that the ultimate size of the tracking errors can be made arbitrarily small. Experimental results are presented for a PUMA 560 manipulator and demonstrate that accurate and robust trajectory tracking can be achieved by using the proposed controllers.     

人造导星技术及导星用激光系统

论述了自适应光学系统对人造导星的需要;简单介绍了两类激光导星;重点描述了销激光导星的产生机理及可用于销激光导星的一些激光系统.