函数单向S-粗集对偶生成的■-模型

利用函数单向S-粗集对偶,给出R-函数等价类[u(x)]的-模型与-t阶单向动态模型的生成及有关概念,给出■-模型与■-单向动态模型生成及有关概念,提出■-单向动态模型序关系定理及动态分离定理,■-模型的动态特征依赖于属性集α上的属性删除。利用这些讨论,给出■-模型生成原理及应用。     

基于改进动态纹理模型的人体运动分析

人体运动分析是计算机视觉领域最活跃的研究课题之一。文中提出2种描述人体运动序列的改进动态纹理模型:二值动态纹理模型和张量子空间动态纹理模型。假设二值图像服从Bernoulli分布,二值动态纹理模型使用二值主成分分析来学习训练模型的参数。张量子空间动态纹理模型将图像看作张量, 引入张量子空间分析的方法分别对其行向量和列向量进行降维,将其转化为低维灰度图像,然后用动态纹理模型描述灰度图像序列。在人体行为和步态数据库上的实验结果验证2种改进动态纹理模型的有效性。     

基于Cardboard平台虚拟博物馆的开发

介绍了Cardboard平台的虚拟博物馆"模型动态加载"模块的开发过程,其中包括了Cardboard与Unity、模型数据文件的设计、模型动态加载几个步骤,可将组织好的模型资源文件动态地添加到虚拟博物馆程序中,实现动态的布展.     

基于逆模型辨识的Wiener型传感器动态补偿研究

在测量系统中许多传感器动态特性是一个非线性Wiener模型,即存在着严重的静态非线性和动态响应滞后.为了补偿动态误差,采用模型参考和Wiener逆模型辨识的算法建立动态补偿单元.补偿单元由一个静态逆模型和动态逆模型构成.通过静态标定方法,采用单输入/单输出的模糊小脑神经网络(SISO-FCMAC)建立传感器静态非线性模...     

动态配置机制及其在水利信息系统中的应用

动态配置是指在软件系统运行时动态地改变系统的配置项。基于构件的软件系统配置项涉及系统的构件组成、构件间的连接关系和构件的物理分布。根据支持软件系统动态配置的反射体系结构,建立了动态配置模型,分析了动态配置模型的构成要素,定义了动态配置模型的元数据,以保障运行时系统一致性为基础,构造了动态配置模型的元协议。最后,通过实例,分析了所提出的动态配置机制在水利信息系统软件功能动态配置中的应用。实践表明,基于反射的系统动态配置模型及其实现机制,能在水利信息系统中有效应用,为解决水利信息系统的资源动态配置、支持动态需求等问题,提供了可行的技术方案。     

基于SVR的传感器Hammerstein模型辨识

提出一种基于支持向量回归机的非线性动态传感器Hammerstein模型辨识方法并给出了相关的数学理论及学习算法.在该模型中,用非线性静态子环节和线性动态子环节串联来描述传感器的非线性动态特性.再利用函数展开将模型的非线性传递函数转换为等价的线性中间模型,并通过SVR求取中间模型参数.最后,推导出中间模型参数与传感器Hammerstein模型参数之间的关系,并由该关系实现非线性静态环节和线性动态环节的同时辨识.用实际力传感器动态标定实验数据进行测试,结果表明与常规非线性传感器辨识方法不同,所提方法只需进行一次动态标定实验就能给出非线性动态模型的数学解析表达式.且建立的力传感器Hammerstein模型阶次为4,而线性动态系统模型则需要6阶才能达到相同的精度.因此该研究为传感器非线性动态系统辨识又提供了一种可选方法.     

基于SVM的电涡流传感器动态建模方法

传感器的动态特性反映了系统动态测试的能力,而时传感器动态特性描述的有效方法是建立传感器的动态模型.本文简单介绍了回归型支持向量机的基本原理,研究了利用支持向量机建立传感器动态模型的方法.利用支持向量机良好的回归拟合能力,建立了电涡流传感器的动态模型.实验结果表明该方法所建模型具有较高的准确性,为改善电涡流传感器的动态特性,实现动态补偿提供了一种较为有效的方法.     

一种改进的动态服务路由模型：P-RSR模型

动态服务路由模型是SOA架构中服务虚拟化策略的实际应用。动态服务路由模型主要分为预测型和反应型2类,该文在分析上述2类动态服务路由模型的基础上,提出一种改进的动态服务路由模型,即预测-反应型服务路由模型(P-RSR模型),并从理论上和实际性能测试两方面证明P-RSR模型是高效和可靠的。     

燃料电池电能与热能建模研究

为分析燃料电池的动态特性,对其发电和发热过程进行了建模研究。燃料电池划分为阳极动态模型、阴极动态模型、电化学电压模型和温度动态模型,分别从流量平衡、能量平衡和经验公式角度进行了机理建模;并采用改变负载和冷却水流量的方式进行测试。仿真结果表明,该模型能模拟燃料电池的电热动态过程,可用于辅助控制设计。     

嵌入作业协调的随机动态车队调度求解策略

针对一类考虑站内装卸货作业协调的随机动态车队调度问题, 建立动态规划模型, 并在此基础上进行改进, 构建单参数动态重构模型和双参数动态重构模型, 进而设计3种单变量作用关系模型和3种双变量作用关系模型, 并给出分解控制参数获取方法. 最后通过仿真和实验研究表明, RM-SDCP模型和RM-DDCP模型可以得到 比传统DP模型更高质量的解, 在RM-DDCP模型与RM-SDCP模型的性能比对中, RM-DDCP模型总体性能优于RM-SDCP模型.     

Biomechanics of manual material handling through simulation: Computational aspects

Computerized human motion simulation allows generation of dynamic human motions on computers. Biomechanical stresses can be estimated using the motions generated on a computer without actually collecting joint coordinate data. A two-dimensional whole-body lifting simulation model is presented in this paper. The model assumes that humans perform lifting activities based on minimization of physical work, subject to various constraints. The simulation method contains three major computation units: trajectory formation unit, dynamics of motion unit, and nonlinear optimization unit. The trajectory formation unit generates smooth polynomials representing motion characteristics of human lifting. Kinematics and kinetics are calculated in the dynamics unit. Objective and constraint functions are evaluated in the optimization unit. Optimal motions are generated by minimizing the objective function, subject to the constraints. Computation methods of the three units and simulation results are presented.     

Parameter identification and sedative sensitivity analysis of an agitation-sedation model

Sedation administration and agitation management are fundamental activities in any intensive care unit. A lack of objective measures of agitation and sedation, as well as poor understanding of the underlying dynamics, contribute to inefficient outcomes and expensive healthcare. Recent models of agitation-sedation dynamics have enhanced understanding of the underlying dynamics and enable development of advanced protocols for semi-automated sedation administration. In this research, the agitation-sedation model parameters are identified using an integral-based fitting method developed in this work. Parameter variance is then analysed over 37 intensive care unit patients. The parameter identification method is shown to be effective and computationally inexpensive, making it suited to real-time clinical control applications. Sedative sensitivity, an important model parameter, is found to be both patient-specific and time-varying. However, while the variation between patients is observed to be as large as a factor 10, the observed variation in time is smaller, and varies slowly over a period of days rather than hours. The high fitted model performance across all patients show that the agitation-sedation model presented captures the fundamental dynamics of the agitation-sedation system. Overall, these results provide additional insight into the system and clinical dynamics of sedation management.     

基于逆动力学模糊规则的单元机组协调控制

通过单元火电机组动态特性分析,获得了一种简单的机组负荷对象逆动力学模型结构.建立了单元机组逆动力学过程模糊规则(IDFR)模型,并利用递推最小二乘辨识方法对机组逆动力学过程模糊规则进行在线修正.将IDFR直接作为控制规则,提出了一种基于IDFR的机组负荷控制方法,构造了单元机组负荷对象协调控制系统.通过仿真实验考察了所提出的控制系统的有效性和适应性.     

锅炉-汽轮机组的协调控制器整定

A simple two-by-two model for a boiler-turbine unit is derived in this paper, which can capture the essential dynamics of the typical process. The coordinated controller is designed based on this model. A PID control structure and a tuning procedure are proposed. The example shows that the method is easy to use and can achieve an acceptable performance.     

The reliability of the stochastic active rotator

The reliability of firing of excitable-oscillating systems is studied through the response of the active rotator, a neuronal model evolving on the unit circle, to white gaussian noise. A stochastic return map is introduced that captures the behavior of the model. This map has two fixed points: one stable and the other unstable. Iterates of all initial conditions except the unstable point tend to the stable fixed point for almost all input realizations. This means that to a given input realization, there corresponds a unique asymptotic response. In this way, repetitive stimulation with the same segment of noise realization evokes, after possibly a transient time, the same response in the active rotator. In other words, this model responds reliably to such inputs. It is argued that this results from the nonuniform motion of the active rotator around the unit circle and that similar results hold for other neuronal models whose dynamics can be approximated by phase dynamics similar to the active rotator.     

Tuning of Coordinated Controllers for Boiler-turbine Units

A simple two-by-two model for a boiler-turbine unit is derived in this paper, which can capture the essential dynamics of the typical process. The coordinated controller is designed based on this model. A PID control structure and a tuning procedure are proposed. The example shows that the method is easy to use and can achieve an acceptable performance.     

Two-degree-of-freedom H-infinity control of combustion in diesel engine using a discrete dynamics model

This paper proposes an H-infinity combustion control method for diesel engines. The plant model is the discrete dynamics model developed by Yasuda et al., which is implementable on a real engine control unit. We introduce a two-degree-of-freedom control scheme with a feedback controller and a feedforward controller. This scheme achieves both good feedback properties, such as disturbance suppression and robust stability, and a good transient response. The feedforward controller is designed by taking the inverse of the static plant model, and the feedback controller is designed by the H-infinity control method, which reduces the effect of the trubocharger lag. The effectiveness of the proposed method is evaluated in simulations using the nonlinear discrete dynamics model.     

Heating and melting deformable models

We develop physically-based graphics models of non-rigid objects capable of heat conduction, thermoelasticity, melting and fluid-like behaviour in the molten state. These deformable models feature non-rigid dynamics governed by Lagrangian equations of motion and conductive heat transfer governed by the heat equation for non-homogeneous, non-isotropic media. In its solid state, the discretized model is an assembly of hexahedral finite elements in which thermoelastic units interconnect particles situated in a lattice. The stiffness of a thermoelastic unit decreases as its temperature increases, and the unit fuses when its temperature exceeds the melting point. The molten state of the model involves a molecular dynamics simulation in which ‘fluid’ particles that have broken free from the lattice interact through long-range attraction forces and short-range repulsion forces. We present a physically-based animation of a thermoelastic model in a simulated physical world populated by hot constraint surfaces.     

半实物仿真综合实验台控制系统方案

构建半实物仿真综合实验台,能够模拟再现2个飞行器的空间交会动力学过程。在此基础上,提出半实物仿真综合实验台控制系统方案。控制系统包括中央控制单元、测控单元、模型计算单元、驱动装置以及六维力传感器,实现对整个实验的控制和管理、在线监视以及驱动机构的动作。该系统设计具有控制实时性以及良好的用户界面,经过实验验证,证明其是稳定、可靠的。     

Control of variable speed wind turbines: Dynamic models

Owing to concern over the environment, there is much interest in renewable sources of electrical power generation, of which one of the most promising is wind power. Wind turbines exploit this energy source to directly generate electrical power. There are essentially two types of windturbines, namely constant speed and variable speed machines. The purpose of this paper is to investigate the dynamics of variable speed wind turbines and determine suitable models to support the control design task. A basic but widely used dynamic representation of variable speed wind turbines and the corresponding models of the control plant dynamics are initially discussed. More detailed, yet still simple models, are derived separately for the rotor aerodynamics, the drive-train dynamics and the power generation unit dynamics before being combined to form the complete model of the wind turbine dynamics. The resulting combined model, in addition to supporting the control design task, enables the extent, to which the basic models adequate represent the wind turbine, to be assessed. It is concluded that the basic models of variable speed wind turbines are not adequate and do not exhibit all the relevant aspects of the dynamics necessary to support the control design.