在线分析仪表在有色冶炼过程中的应用

介绍了几种重要分析仪表的应用情况,探讨了分析仪表（系统）在选型、使用、改进及维护方面的一些问题.     

基于FIR的电量脉冲采集方法

介绍FIR原理、网络结构以及如何用FIR低通滤波器实现可靠的电能脉冲采集.     

Discovering new invertebrate neuropeptides using mass spectrometry

Neuropeptides are a complex set of messenger molecules controlling a wide array of regulatory functions and behaviors within an organism. These neuromodulators are cleaved from longer protein molecules and often experience numerous post-translational modifications to achieve their bioactive form. As a result of this complexity, sensitive and versatile analysis schemes are needed to characterize neuropeptides. Mass spectrometry (MS) through a variety of approaches has fueled the discovery of hundreds of neuropeptides in invertebrate species in the last decade. Particularly successful are direct tissue and single neuron analyses by matrix-assisted laser desorption/ionization (MALDI) MS, which has been used to elucidate approximately 440 neuropeptides, and examination of neuronal homogenates by electrospray ionization techniques (ESI), also leading to the characterization of over 450 peptides. Additional MS methods with great promise for the discovery of neuropeptides are MS imaging and large-scale peptidomics studies in combination with a sequenced genome.     

On the sampling of three-dimensional polycrystalline microstructures for distribution determination

How to sample three-dimensional microstructure and effectively reduce experimental error is a challenging problem. Taking seven single-phase polycrystalline structures generated by 400×400×400 Potts Monte Carlo simulation as the study object, effects of sampling strategy on the determination of various characteristic parameters of the grain size distribution and grain topology distribution are studied. The mean voxel value (or volume) of individual grains in the three-dimensional simulated microstructure varies from 4.56×10(4) to 1.0×10(3) , and the number of grains contained in the structure varies from 63 901 to 1403. The results show that, a minimum of 200 sampled grains can ensure the relative error to be less than 5% for determination of the mean grain volume, the mean grain face number and the coefficient of variance of the distribution of grain size and the grain face number. Whereas for the coefficient of the skewness and the kurtosis of grain size distribution or grain face number distribution, a minimum of 800 sampled grains are required for the same error level. However, if some exceptional big grains appear, e.g. a grain larger than with eight multiples of mean grain volume and/or three multiples of mean grain face number, abnormal values of the two parameters would be resulted, even the number of examined grains is over 1000.     

Unbiased estimation of curve length in 3-D using vertical slices

An efficient sampling procedure is presented for estimation of total line length per unit volume L_v. It involves the following steps: (1) choose a vertical axis in the specimen, and cut the specimen to obtain VUR vertical slices of constant thickness Δ such that parallel planes of the slices contain the vertical direction; (2) observe the projected image of a vertical slice using transmission microscopy such that beam direction is perpendicular to the slice; (3) count the number of intersections of the projected images of the lineal features of interest with cycloid-shaped test lines whose minor axis is perpendicular to the vertical axis. The expected value of the number of intersections per unit length _prj is related to L_v as follows: Thus, L_v can be estimated from the measurements performed on the projected images of VUR vertical slices.     

数字FIR滤波器的MATLAB设计和仿真

本文介绍了数字滤波器的设计基础及用频率取样法设计FIR滤波器的方法 ,运用MATLAB语言实现了低通滤波器的设计以及用Simulink仿真实现其具体结构。     

统计抽样在审计中的运用

对统计抽样在审计中的意义进行概述。强调在市场经济体制中,经济越发后,越需要加强审计的预警监控。举例说明了运用固定样本容量抽样对内部控制制度进行的符合性测试,为实质性测试确定审查的范围、重点、数量和方法提供了依据。在实质性测试中通过举例说明了变量抽样差异估计的应用。     

Selective Sampling Using the Query by Committee Algorithm

We analyze the query by committee algorithm, a method for filtering informative queries from a random stream of inputs. We show that if the two-member committee algorithm achieves information gain with positive lower bound, then the prediction error decreases exponentially with the number of queries. We show that, in particular, this exponential decrease holds for query learning of perceptrons.     

基于事件触发的神经网络控制器稳定性分析

针对非线性系统稳定性问题,设计了基于事件触发的神经网络控制器来稳定非线性系统,控制器只有在触发规则满足的条件下,才更新控制参数,降低了网络传输率。算法开始先建立非线性系统模型,在采样过程中引入事件触发机制,并且设计了神经网络控制器,对于系统中包含的传输时滞,引入系统时滞模型,运用输入延迟法将同步控制器求解问题转化为时滞系统的稳定性问题。再通过构造分段Lyapunov-Krasovskii泛函并结合Jensen不等式,给出了非线性系统稳定条件。与传统数据采样系统相比,本文所提出的方法有效地增大了采样间隔,结尾通过例子仿真验证了所提出方法的有效性。     

基于密度峰值优化的谱聚类算法

针对经典谱聚类算法无法自适应确定聚类数目、以及在处理大数据量的聚类问题时效率不高的问题,本文提出了一种基于密度峰值优化的谱聚类算法。该方法首先计算数据对象的局部密度,以及每个数据对象与较其他数据对象的最小距离,并依据一定的规则自适应产生初始聚类中心,确定聚类数目。其次,使用Nystr?m抽样来降低特征分解的计算复杂度以达到提高谱聚类算法的效率。实验结果表明,本文方法能够准确地得到聚类数目,并且有效提高聚类的准确率和效率。