原文:
Model Reduction 模型降阶 采用最佳途径将一个高阶(或非参数)模型降为更低阶模型的过程。
**MV **操作变量。
Noise 噪声 干扰真实或原始信号的某一信号或某信号的组成部分。不可测量的输入影响了过程行为。信号的不确定性或随机性部分。
**Non-parametric Model **非参数模型 模型不由特定的模型结构所限制。
**Overlay ** 覆盖 多个趋势(响应)铺设在彼此的顶部或同一坐标轴上。
**Parametric Model **参数模型 模型的结构被定义,且由固定数目的参数来定义模型。
**PCTP ** 过程控制技术包。.
**PRBS ** 伪随机二进制序列。也被称为PRBNS,其中N是噪声(noise),S是信号(signal)。
**Prediction **预测 模型输入一组输入变量后,试图模拟真实信号响应的过程。
**Prefilter **预滤波器 当信号被用于模型估计练习前时,滤波器应用于其中一个或所有信号。PVR 过程变量探索器。
QMI 质量测量仪或性能分析仪。
Ramp 一个积分过程或过程变量。
Regression 回归 回归是用于表征当输入变量变化时,哪个输出变量产生变化的方式。最优回归是通过使用最小二乘法最小化预测输出与实际误差得到的。
**Residual **残差 代表了模型拟合后输出的未知变化。它是预测输出与实际输出之间的偏差。也被称为误差。
**RQE ** 稳健质量预估器。
Sample Period 采样周期 连续信号连续采样周期之间的时间间隔。
Settling-time 稳态时间 当输入改变时,过程/模型重新进入稳态所需要的时间。
Signal-to-Noise Ratio 信噪比 信号部分与噪声部分的比例。信号中噪声含量越多,信噪比越低。SNR = σy /σn 其中σy是信号y(也可以是x)的测量值,σn是噪声含量。
Simulation 仿真 确定性预测 其中没有基于历史输出测量值的反馈用于更新预测。
**SISO **单输入单输出。
**SMOC **壳牌多变量优化控制。
**State-space **状态空间 一个用于定义系统的抽象数学空间。在动态系统中,根据系统状态系统可被建模为一组一阶微分(差分)方程。
**Stationary **稳定 信号到达稳态是在一个平均值周围浮动的。变量与非稳定或漂移相反的,是不在固定平均值周围浮动。
Steady-State 稳态 当一个过程变量不随时间变化时的状态。
**Step Response **阶跃响应 对自变量施加一单位阶跃,获得的因变量的响应。
Step Testing 阶跃测试 通过给输入(自变量)一个阶跃从而给过程扰动。
Tag 位号 过程变量标签。偶尔也称为点。
Variance 方差 方差描述了数值与期望值(或平均值)的差异。它是标准差的平方。这里指的数值既可以是一个直接的测量值,也可以是测量值的函数。
**White Noise **白噪声 与本身不相关(无显著自相关系数 lags>0)且完全不可预测的时间序列(或序列)。
Zero-order Hold 零阶保持 当连续信号进行采样时,模拟信号在一个采样间隔点进行采样,并且一直“保持”该值直到下一个采样时间。因为零阶保持的缘故,在输入输出系统的情况下当输入变量变化时,至少需要一个采样周期输出变量才会变化。
原文:
Model Reduction The process of reducing a higher-order (or non-parametric) model into a lower order model in the best way.
MV Manipulated Variable.
Noise Any signal or a component of a signal that interferes with the true or original signal. Unmeasured inputs affecting process behavior. The non-deterministic or stochastic component of a signal.
**Non-parametric Model **A model not restricted by a specific model structure.
Overlay The laying of multiple trends (responses) on top of each other or on the same plot axes.
Parametric Model A model whose structure is set and is defined by a fixed number of parameters.
**PCTP ** Process Control Technology Package.
PRBS Pseudo Random Binary Sequence. Also referred to as PRBNS with N for noise and S for signal.
Prediction The response of a model to a set of inputs that tries to emulate a true signal.
Prefilter Filter applied to one or all of the signals before they are used in a model estimation exercise.
**PVR ** Process Variable Retriever.
QMI Quality Measuring Instrument or property analyzer.
Ramp An integrating process or process variable.
Regression Regression is used to characterize the manner by which an output variable changes as input variables changes. The best regression is obtained using a least-squares minimization of the output prediction version actual errors.
Residual Represents the unexplained variation of an output after fitting of a model. It is the difference between the actual output and the predicted output. Also known as error.
**RQE ** Robust Quality Estimator.
**Sample Period ** The time interval between consecutive samplings of continuous signal.
Settling-time Time taken by a process/model to become steady after an input change to it was made.
**Signal-to-Noise Ratio ** The ratio of the content of a signal to the noise content in it. The higher the noise level in a signal, the lower this ratio. SNR = σy /σn where σy is a measure of the content of the signal y (sometimes x) and σn is the content of the noise.
Simulation The deterministic prediction, where no feedback based on past measurements of
the output is used in updating the prediction.
SISO Single-Input Single-Output.
SMOC Shell Multivariable Optimizing Control.
State-space An abstract mathematical space used to define a system. In a dynamic system,
the system can be modeled as a set of first order differential (difference) equations in terms of the system states.
**Stationary **A stationary signal is one in which variation is around a mean value. The opposite of a non-stationary or drifting variable, in which variation is not around a fixed mean.
Steady-State The condition when a process variable is not changing with time.
Step Response The response of a dependent variable to a unit step change an independent variable.
**Step Testing **Perturbing a process using step changes in inputs (independents).
**Tag **A process variable label. Also referred to as point occasionally.
Variance Variance describes variability of a quantity about an expected (or mean) value. It is the square of the standard deviation. The quantity referred to can be a directly measured value or a function of measured values.
**White Noise **A time series (or sequence) that is completely unpredictable and therefore is uncorrelated with itself (no significant autocorrelation coefficients for lags > 0).
Zero-order Hold When a continuous signal is sampled, the analog signal is sampled at a sample interval and is “held” constant at that value until the next sampling instant. In the context of input-output systems, when an input change is made, the change usually takes at least one sampling interval before it shows up in the output because of zero-order hold.
2016/4/16