计算机控制系统的抗干扰技术

计算机控制系统中存在各种不同的干扰源，为此，必须采取各种软件和硬件上的抗干扰措施来保证计算机控制系统能长期、可靠、安全、稳定地运行。     

几种消除计算机干扰方法的效果的对比研究

在实际的计算机控制系统中，存在多种形式的干扰或扰动，这些干扰或扰动伴随着系统的动态响应而存在，使得被控对象不能很好地跟踪期望信号或平稳地工作在设定点上。为了得到期望的高精度控制效果，需要结合实际控制系统来分析研究不同干扰的来源及其消除方法。本对一个计算机控制的直流电机随动系统中各种干扰做了分析并提出了几种消除方法，实际电机上的对比实施结果表明这些方法的有效性。     

可编程控制器组成的皮革生产过程控制系统

本文介绍了一个实现皮革生产过程计算机控制的系统，给出了控制系统的组成以及为实现计算机控制而需对转鼓进行改造的方法。文章较详细地论述了实现皮革生产过程计算机控制的方法和具体调节原理。     

机器人分布式计算机控制系统结构的性能分析

本文从多处理机系统组织结构入手，根据多关节机器人控制特点，提出了组成机器人分布式计算机控制系统的三种结构。依据分布式系统理论，应用马尔可夫过程，对此三种体系结构的工作效率，建立了数学模型，给出了效率曲线，并从不同角度对三种结构的处理能力进行了分析。为设计机器人分布式计算机控制系统提供了理论依据。     

小型计算机控制系统的分析与设计

本文首先回顾了计算机控制系统的结构，并介绍了计算机控制系统的软硬件技术的发展。在此基础上提出了一种小型计算机控制系统的设计方案。最后给出了一个实际例子。     

小型计算机控制系统的分析与设计

本文首先回顾了计算机控制系统的结构，并介绍了计算机控制系统的软硬件技术的发展。在此基础上提出了一种小型计算机控制系统的设计方案。最后给出了一个实际例子。     

计算机控制系统的故障诊断

介绍了计算机控制系统的故障原因，故障诊断方法，并给出了一诊断实例。     

空分装置计算机控制系统的硬件设计

介绍了空分装置计算机控制系统的硬件设计方法，主要包括以下几个部分。计算机控制系统硬件设计依据：有输入输出信号的类型和点数，控制回路，顺序逻辑控制，联锁控制。控制系统的选择：选择计算机控制系统时除考虑要满足工艺要求和控制功能外，还考虑性能价格比，技术支持，开放性。模板的选择：主要包括CPU模板、电源模板、机架间连接模板、I／O模板等。信号地址的确定：信号地址的确定与I／O模块的分布是相互关联的。     

通用工业过程计算机控制系统开发

本文提出了一种开发通用工业计算机控制系统的方法，包硬件组合和工业控制组态软件的设计，以提高应用系统开发水平。     

GE Fanuc嵌入式计算机控制系统在Ф340mm连轧管机组中的应用

本文介绍了GE Fanuc嵌入式计算机控制系统在340连轧管机组中的应用。结合工艺控制需求，介绍了嵌入式计算机控制系统的结构、配置及功能特点，以实际的辊缝控制效果图，验证了GE Fanuc嵌入式计算机控制系统的性能指标能完全满足该连轧机液压辊缝控制系统的快速、高精度要求。     

A GREEDY ALGORITHM FOR A GENERALIZATION OF THE RECONSTRUCTION PROBLEM

The aim of the reconstruction problem is to determine from among all relevant structure systems those which allow us to reconstruct a given overall system to an acceptable degree of approximation. This paper considers a more general form of the reconstruction problem. Instead of restricting the reconstruction to structure systems, substates in general are allowed in the reconstruction. Furthermore, the overall system need not be known in its entirety to formulate a reconstruction. A very effective and efficient algorithm for this generalized reconstruction problem is presented.     

一类非线性系统的故障重构与容错控制

针对一类满足Lipschitz条件的仿射非线性系统,提出一种执行器故障重构与容错控制方法。通过非奇异变化矩阵对系统进行降阶,设计出滑模故障重构观测器,优化滑模策略,使滑模故障重构观测器渐进估计系统的状态,并给出稳定性分析。运用等价输出控制方法直接获取故障信息,实现执行器故障的检测与重构。设计出主动容错控制器,通过补偿控制,完成执行器故障的容错控制。最后通过数值仿真验证了方法的可行性与有效性。     

智能网络取证系统

智能网络取证为网络防护提供了一种新的措施,弥补了原有网络安全体系中的不足。该系统包括数据采集、数据过滤、数据存储、管理控制和智能取证分析等部分。在数据获取的时候采用了规则过滤机制,减少了系统的负载,提高了电子证据的精确性。在数据获取的时候,系统采用了TCP/IP的实时重组,可以对应用层数据进行过滤和检测。对于获得的数据,分析模块采用多种方式综合分析入侵行为,包括协议分析、专家系统、应用数据还原、入侵检测等技术。在网络环境中,它与IDS,防火墙,VPN等技术结合,可以提供更加安全可靠的防护体系。     

Signal reconstruction in the presence of finite‐rate measurements: finite‐horizon control applications

In this paper, we study finite‐length signal reconstruction over a finite‐rate noiseless channel. We allow the class of signals to belong to a bounded ellipsoid and derive a universal lower bound on a worst‐case reconstruction error. We then compute upper bounds on the error that arise from different coding schemes and under different causality assumptions. When the encoder and decoder are noncausal, we derive an upper bound that either achieves the universal lower bound or is comparable to it. When the decoder and encoder are both causal operators, we show that within a very broad class of causal coding schemes, memoryless coding prevails as optimal, imposing a hard limitation on reconstruction. Finally, we map our general reconstruction problem into two important control problems in which the plant and controller are local to each other, but are together driven by a remote reference signal that is transmitted through a finite‐rate noiseless channel. The first problem is to minimize a finite‐horizon weighted tracking error between the remote system output and a reference command. The second problem is to navigate the state of the remote system from a nonzero initial condition to as close to the origin as possible in finite‐time. Our analysis enables us to quantify the tradeoff between time horizon and performance accuracy, which is not well studied in the area of control with limited information as most works address infinite‐horizon control objectives (e.g. stability, disturbance rejection). Copyright © 2009 John Wiley & Sons, Ltd.     

A generic system for form dropout

Recent advances in intelligent character recognition are enabling us to address many challenging problems in document image analysis. One of them is intelligent form analysis. This paper describes a generic system for form dropout when the filled-in characters or symbols are either touching or crossing the form frames. We propose a method to separate these characters from form frames whose locations are unknown. Since some of the character strokes are either touching or crossing the form frames, we need to address the following three issues: 1) localization of form frames; 2) separation of characters and form frames; and 3) reconstruction of broken strokes introduced during separation. The form frame is automatically located by finding long straight lines based on the block adjacency graph. Form frame separation and character reconstruction are implemented by means of this graph. The proposed system includes form structure learning and form dropout. First, a form structure-based template is automatically generated from a blank form which includes form frames, preprinted data areas and skew angle. With this form template, our system can then extract both handwritten and machine-typed filled-in data. Experimental results on three different types of forms show the performance of our system. Further, the proposed method is robust to noise and skew that is introduced during scanning     

Axiomatic approach to computational attention

Here we describe, in terms of a decision problem, any situation in which a computational system will be forced to allocate attention at any time to one spatial location to improve the reconstruction fidelity on a neighborhood of the chosen point. The result is a rational model of computational attention in which a multi-bitrate attention map will provide us with the attention score for each spatial location at high and low quality versions of the image reconstruction. At any time a rational system should choose, even though without any outside knowledge, among alternative spatial locations in such a way as to avoid certain forms of behavioral inconsistency. We compare the performance between a rational approach of computational attention and various models for predicting visual target distinctness, using scenes that represent military vehicles in complex rural backgrounds.     

Simulation Guided Hair Dynamics Modeling from Video

In this paper we present a hybrid approach to reconstruct hair dynamics from multi‐view video sequences, captured under uncontrolled lighting conditions. The key of this method is a refinement approach that combines image‐based reconstruction techniques with physically based hair simulation. Given an initially reconstructed sequence of hair fiber models, we develop a hair dynamics refinement system using particle‐based simulation and incompressible fluid simulation. The system allows us to improve reconstructed hair fiber motions and complete missing fibers caused by occlusion or tracking failure. The refined space‐time hair dynamics are consistent with video inputs and can be also used to generate novel hair animations of different hair styles. We validate this method through various real hair examples.     

Alias-free voxelization of geometric objects

Introduces a new concept for alias-free voxelization of geometric objects based on a voxelization model (V-model). The V-model of an object is its representation in 3D continuous space by a trivariate density function. This function is sampled during the voxelization and the resulting values are stored in a volume buffer. This concept enables us to study general issues of sampling and rendering separately from object-specific design issues. It provides us with a possibility to design such V-models, which are correct from the point of view of both the sampling and rendering, thus leading to both alias-free volumetric representation and alias-free rendered images. We performed numerous experiments with different combinations of V-models and reconstruction techniques. We have shown that the V-model with a Gaussian surface density profile combined with tricubic interpolation and Gabor derivative reconstruction outperforms the previously published technique with a linear density profile. This enables higher fidelity of images rendered from volume data due to increased sharpness of edges and thinner surface patches     

一种基于会聚式体视模型的三维表面重建方法

本文在推导并简化会聚式体视模型视差公式的基础上,基于充分的生理依据,选取多尺度高斯微分滤波器滤波向量为匹配元,采用随机松弛方法的思想,设计了一个分层优化三维重建算法。算法利用双向匹配发现存在不利因素区域,随后对目标函数各项合理加权,从而改善了在该区域的重建效果。该算法能有效地直接产生密集的视差场,经实验验取得了良好的效果。     

A comparison of volumetric information gain metrics for active 3D object reconstruction

In this paper, we investigate the following question: when performing next best view selection for volumetric 3D reconstruction of an object by a mobile robot equipped with a dense (camera-based) depth sensor, what formulation of information gain is best? To address this question, we propose several new ways to quantify the volumetric information (VI) contained in the voxels of a probabilistic volumetric map, and compare them to the state of the art with extensive simulated experiments. Our proposed formulations incorporate factors such as visibility likelihood and the likelihood of seeing new parts of the object. The results of our experiments allow us to draw some clear conclusions about the VI formulations that are most effective in different mobile-robot reconstruction scenarios. To the best of our knowledge, this is the first comparative survey of VI formulation performance for active 3D object reconstruction. Additionally, our modular software framework is adaptable to other robotic platforms and general reconstruction problems, and we release it open source for autonomous reconstruction tasks.