Probabilistic linear models for multiresolution estimation in gray-level images

A multiresolution analysis of digital gray-level images is presented. A gray-level multi-scale framework is determined from two main assumptions: the gray scale is binary at the finest spatial resolution, and the gray levels of composed regions are obtained additively. In order to interrelate the gray-level histograms of the same image at different resolutions, probabilistic linear models are developed, which are then applied for estimation. Linear-optimization theory is used as a way of constructing such models. A general procedure for image processing is sketched, based on gray-level estimation. A versatile algorithm for nonlinear filtering is derived. Some examples of prospective applications are given.This work was partially supported by grant TIC91-646 from the DGYCIT of the Spanish Government.     

用基团贡献法预测纯物质蒸气压

对应状态原理与基团贡献法结合，提出一个新的蒸气压估算方程（ＲＬＹＭ）。通过对烷烃、烯烃、炔烃、环烷烃、环烯烃、醇、环醇、酮、醚、芳烃、酚、萘在内的１７４种有机物质蒸气压实验数据的关联，获得了３０种基团的贡献参数值。新模型的预测精度优于现有的对应状态法，并且对高碳分子仍有较好的估算精度。总的关联误差小于１．１７％。     

Remarks on the mean square tracking error

The purpose of this paper is to extend recent results of Ljung and Priouret to a more general class of regressors.     

Control of the quality of polymer products in continuous reactors: comparison of performance of state estimators with and without updating of parameters

In the paper the control of the product quality in polymerization reactors is analysed in the presence of persistent perturbations (unmodeled disturbances, modeling errors), as met in industrial reactors. The free radical polymerization of methyl-methacrylate in a continuous stirred tank reactor is studied. It is shown that state estimators (Extended Kalman Filters) with constant parameters cannot give offset free performance. Criteria for the selection of a set of parameters to be updated as additional states in the filter and to evaluate their effectiveness in opposing the action of realistic perturbations are given by an analysis of the linearized model of the system. Performance of different types of estimators, including one and two-time scale filters, with and without updating of parameters, is analysed by simulation on the full order process and the predictions made by previous analysis are confirmed. In the most common case of presence of perturbations affecting the energy balance and the concentration of initiator in the reactor, offset free control of the molecular weight of the product can be achieved by means of a filter which is based only on measurements of temperature and conversion and makes an update of two parameters. In the case that also the kinetic model of the polymerization reaction is affected by errors, a two-time scale filter, which makes use also of Molecular Weight values and updates three parameters, becomes necessary to obtain offset free performance.     

视频编码中的块运动估计算法

在视频压缩的一些国际标准，如Ｈ．２６１，Ｈ．２６３，ＭＰＥＧ０－１，ＭＰＥＧ－２，ＨＤＴＶ中，视频系统编码器的复杂性最主要取决于运动估计。下文以ＭＰＥＧ－２编码器为例，通过计算机模拟实验，得出了一些常用运动估计算法的对比实验结果，以及采用常用的几种匹配函数的对比实验结果。     

MIKEII 软件系统在穆棱河流域面源污染估算中的应用

穆棱河流域面源污染入河量调查和估算采用了MIKEII软件系统，根据水质、水量实测数据，在参数率定和模型验证的基础上．对穆棱河部分河段的水质进行模拟，拟合出面源入河量和年内分布。经验证计算结果较其他方法更合理可靠。     

计及PMU的混合非线性状态估计新方法

提出一种将同步相量测量单元（PMU）的直接电压相量量测变换为间接支路电流量测，并与监控与数据采集（SCADA）量测量一起进行混合迭代的非线性状态估计方法。对构造等效电流修正量而带来的间接量测误差进行了详细和定量的分析，并对该混合估计算法的精度进行了定性分析和定量计算。理论分析和算例表明，该方法可以获得较高的估计精度，在收敛次数和滤波效果上也有所改进。     

高分辨率双侧向测井响应数值模拟分析

 我国自行研制的新型的高分辨率双侧向测井仪已逐渐投入大规模的生产应用，可为解决油田薄层油气藏的勘探开发问题提供有力的支持。本文利用有限元方法对新型的高分辨率双侧向测井仪及国内目前大规模应用的常规双侧向测井仪的分层能力、探测深度、侵入影响和井眼影响等响应特征进行了数值模拟，并对其测井响应进行了对比分析。数值模拟表明：与常规双侧向测井相比，虽然高分辨率双侧向测井资料井眼的影响更复杂，但测量结果既能得到较高纵向分辨率，又具有较深的径向探测深度，基本上可以取代常规双侧向测井仪在测井中应用。文中数值模拟结果可以为测井作业人员和解释人员在资料验收及解释处理等方面提供参考和指导。     

机载雷达成像中的两种改进多普勒质心估计算法

多普勒质心估计是机载脉冲多普勒雷达DBS成像技术中最为关键的步骤之一.本文针对载机惯导参数误差较大的实际情况,提出了改进的频域和时域多普勒质心估计算法.新的算法克服了传统算法受地面场景非均匀性和回波信号起伏的影响,大大提高了估计的精度.最后将这些算法用于某型脉冲多普勒雷达的实测数据,成像结果证明了算法的有效性.     

Construction of a control system for disturbance rejection using a dual observer

A well‐known control system which can reduce the adverse effects of disturbances is a disturbance observer. However, in many cases of mechanical systems, system disturbances which do not satisfy the matching condition may be imposed. Therefore, it may be difficult to reduce the adverse effects of the disturbances by the traditional disturbance observer. In this paper, a method of control system synthesis for disturbance rejection using a dual observer is proposed. This method is based on the zeroing induced by the disturbance localization problem. This problem may be solved by dividing the state space into observable subspace and unobservable subspace. As compared with an H_∞ controller based on perfect observation, the usefulness of the proposed control system for disturbance rejection is demonstrated by numerical simulations for a two‐mass spring system. © 2002 Scripta Technica, Electr Eng Jpn, 138(4): 50–60, 2002; DOI 10.1002/eej.1138