Abstract: A method includes acquiring process data collected in an industrial process control and automation system. The method also includes reducing a dimension space of the process data by combining two or more parameters of the process data or examining a frequency response of the process data. The method further includes determining a change in a process based on a change in the process data in the reduced dimension space. The method also includes outputting a result based on the determined change in the process.

Abstract: A controller reference trajectory design technique to enable high-performing automatic grade change performed by a model predictive control (MPC). Techniques include: (1) automatic determination of appropriate process output reference trajectory delays to enable optimum coordination of process input movements; (2) providing the entire planning process output reference trajectory ramp at the start of the grade change instead of just incrementally as the grade change progresses, again enabling movement of the process inputs to drive process outputs along the planned future path instead of just towards the current target; and (3) use of the process input forced ramping to allow linear ramping of process inputs with optimal coordination of other process input movements to keep all process outputs following the desired trajectories. The technical benefits are faster and higher performing grade changes.

Abstract: A method includes acquiring process data collected in an industrial process control and automation system. The method also includes reducing a dimension space of the process data by combining two or more parameters of the process data or examining a frequency response of the process data. The method further includes determining a change in a process based on a change in the process data in the reduced dimension space. The method also includes outputting a result based on the determined change in the process.

Abstract: Sheetmaking cross-directional (CD) control requires a sophisticated model-based controller whose operation requires an accurate model of process behavior, but due to the complexity of the process, identifying these process models is challenging. Current techniques rely on open-loop process experimentation. Using non-causal scalar transfer functions for the steady-state CD process model and controller model avoid the problem of large dimensions associated with the CD process. These non-causal transfer functions can be represented by causal transfer functions that are equivalent to the non-causal ones in the sense of the output spectrum. A closed-loop optimal input design framework is proposed based on these causal equivalent models. CD actuators have responses in both sides along the cross direction which can be viewed as a non-causal behavior.

Abstract: An apparatus includes a transmitter configured to transmit a signal including an electromagnetic pulse towards material in a tank. The apparatus also includes a receiver configured to receive a signal including multiple reflections of the pulse. The apparatus further includes at least one processing device configured to process the received signal and determine a measurement associated with the material in the tank. To process the received signal, the at least one processing device is configured to fit multiple models onto the received signal, select one of the models, identify at least one of the multiple reflections in the received signal using the selected model, and determine the measurement using the at least one identified reflection in the received signal. Each model is constructed from a superposition of multiple types of pulse reflections.

Abstract: Automated parameter tuning techniques for cross-directional model predictive control for paper-making under user-specified parametric uncertainties to reduce variability of the actuator and measurement profiles in the spatial domain is proposed. Decoupling properties of the spatial and temporal frequency components permit separate controller design and parameter tuning. CD-MPC design that explicitly accounts for parametric model uncertainty while finding MPC cost function weighing matrices that prevent actuator picketing and guarantee robust stability of the spatial CD profile. Picketing refers to periodic variation patterns in the actuator array.

Abstract: Automated parameter tuning techniques for cross-directional model predictive control for paper-making under user-specified parametric uncertainties are developed. The CD-MPC design explicitly accounts for parametric model uncertainty while finding a value for the CD profile trajectory generation that minimizes the CD settling time of the measurement 2 sigma spread and does not exceed an overshoot limit for actuator 2 sigma spread. The inventive technique includes: (i) providing uncertainty specifications for the temporal parameters of the process model, (ii) specifying 2 sigma overshoot limits for the CD actuator profile, (iii) using robust stability theory to find a minimum bound for the profile trajectory tuning parameter, (iv) using a frequency domain technique to reduce the search range for the profile trajectory tuning parameter, and (v) performing an intelligent search for the tuning parameter that minimizes measurement 2 sigma settling time without exceeding the actuator 2 sigma overshoot limit.

Abstract: A controller reference trajectory design technique to enable high-performing automatic grade change performed by a model predictive control (MPC). Techniques include: (1) automatic determination of appropriate process output reference trajectory delays to enable optimum coordination of process input movements; (2) providing the entire planning process output reference trajectory ramp at the start of the grade change instead of just incrementally as the grade change progresses, again enabling movement of the process inputs to drive process outputs along the planned future path instead of just towards the current target; and (3) use of the process input forced ramping to allow linear ramping of process inputs with optimal coordination of other process input movements to keep all process outputs following the desired trajectories. The technical benefits are faster and higher performing grade changes.

Abstract: A method of level finding includes providing characteristics of a shape of a transmitted pulse in time domain launched onto a waveguide into a tank having at least one material therein, physical properties of the waveguide and real and imaginary dielectric characteristics of the material at a frequency of the pulse. A level finding algorithm having a coarse search and a fine search is implemented, where the coarse search minimizes a prediction error between an echo signal (echo curve y(k)) and a sampled pulse model echo p(k) to obtain an objective function J(k) in a vicinity of a minimum prediction error (k*). The fine search calculates at least one minimum or maximum using J(k) in the vicinity of k*. The minimum or the maximum corresponds to a level of the material or an interface involving the material.

Abstract: Controlling a multiple-array, sheetmaking cross-directional process with a multivariable model predictive controller (MPC) employs a cost function incorporating a prediction horizon. The MPC provides a measurement profile target reference trajectory over the prediction horizon of the MPC cost function. Improved CD-MPC performance is achieved by employing a measurement profile target reference trajectory over the prediction horizon in the MPC cost function. A series of target profiles creates a reference trajectory to bring the cross-direction measurements smoothly from their current profile to the final target. By carefully designing the reference trajectory, the CD-MPC exhibits a good measurement response without aggressive control action. The current measurement target profile can be filtered through a first order plus deadtime process at each controller update and repeating the filter operation once for each step of the MPC prediction horizon generates a full reference trajectory for the profile.

Abstract: A method of simulating a pulsed radar gauge (PRG) on a tank. Provided are (i) a parametrized model of an echo reflection responsive to a transmitted radar pulse defined by an initial spatial model function, a first signal model modeling the pulse traveling through the media, and a second signal model modeling reflection and transmission of the pulse striking boundaries involving the media, and an (ii) echo curve calculation (ECC) program. The ECC program divides the signal path into path components for the pulse using the first and second signal model together as a recursive program with stop conditions to indicate an end result for the path components when taken together for reflected signals reaching the transceiver include locations of reflections and respective amplitudes. A shape of the initial model is placed at reflection locations using their respective amplitudes applied to size their amplitude to generate a simulated echo curve.

Abstract: An apparatus includes a transmitter configured to transmit a signal including an electromagnetic pulse towards material in a tank. The apparatus also includes a receiver configured to receive a signal including multiple reflections of the pulse. The apparatus further includes at least one processing device configured to process the received signal and determine a measurement associated with the material in the tank. To process the received signal, the at least one processing device is configured to fit multiple models onto the received signal, select one of the models, identify at least one of the multiple reflections in the received signal using the selected model, and determine the measurement using the at least one identified reflection in the received signal. Each model is constructed from a superposition of multiple types of pulse reflections.

Abstract: Automated parameter tuning techniques for cross-directional model predictive control for paper-making under user-specified parametric uncertainties are developed. The CD-MPC design explicitly accounts for parametric model uncertainty while finding a value for the CD profile trajectory generation that minimizes the CD settling time of the measurement 2 sigma spread and does not exceed an overshoot limit for actuator 2 sigma spread. The inventive technique includes: (i) providing uncertainty specifications for the temporal parameters of the process model, (ii) specifying 2 sigma overshoot limits for the CD actuator profile, (iii) using robust stability theory to find a minimum bound for the profile trajectory tuning parameter, (iv) using a frequency domain technique to reduce the search range for the profile trajectory tuning parameter, and (v) performing an intelligent search for the tuning parameter that minimizes measurement 2 sigma settling time without exceeding the actuator 2 sigma overshoot limit.

Abstract: Automated parameter tuning techniques for cross-directional model predictive control for paper-making under user-specified parametric uncertainties to reduce variability of the actuator and measurement profiles in the spatial domain is proposed. Decoupling properties of the spatial and temporal frequency components permit separate controller design and parameter tuning. CD-MPC design that explicitly accounts for parametric model uncertainty while finding MPC cost function weighing matrices that prevent actuator picketing and guarantee robust stability of the spatial CD profile. Picketing refers to periodic variation patterns in the actuator array.

Abstract: Controlling a multiple-array, sheetmaking cross-directional process with a multivariable model predictive controller (MPC) employs a cost function incorporating a prediction horizon. The MPC provides a measurement profile target reference trajectory over the prediction horizon of the MPC cost function. Improved CD-MPC performance is achieved by employing a measurement profile target reference trajectory over the prediction horizon in the MPC cost function. A series of target profiles creates a reference trajectory to bring the cross-direction measurements smoothly from their current profile to the final target. By carefully designing the reference trajectory, the CD-MPC exhibits a good measurement response without aggressive control action. The current measurement target profile can be filtered through a first order plus deadtime process at each controller update and repeating the filter operation once for each step of the MPC prediction horizon generates a full reference trajectory for the profile.

Abstract: Sheetmaking cross-directional (CD) control requires a sophisticated model-based controller whose operation requires an accurate model of process behavior, but due to the complexity of the process, identifying these process models is challenging. Current techniques rely on open-loop process experimentation. Using non-causal scalar transfer functions for the steady-state CD process model and controller model avoid the problem of large dimensions associated with the CD process. These non-causal transfer functions can be represented by causal transfer functions that are equivalent to the non-causal ones in the sense of the output spectrum. A closed-loop optimal input design framework is proposed based on these causal equivalent models. CD actuators have responses in both sides along the cross direction which can be viewed as a non-causal behavior.

Abstract: A method of simulating a pulsed radar gauge (PRG) on a tank. Provided are (i) a parametrized model of an echo reflection responsive to a transmitted radar pulse defined by an initial spatial model function, a first signal model modeling the pulse traveling through the media, and a second signal model modeling reflection and transmission of the pulse striking boundaries involving the media, and an (ii) echo curve calculation (ECC) program. The ECC program divides the signal path into path components for the pulse using the first and second signal model together as a recursive program with stop conditions to indicate an end result for the path components when taken together for reflected signals reaching the transceiver include locations of reflections and respective amplitudes. A shape of the initial model is placed at reflection locations using their respective amplitudes applied to size their amplitude to generate a simulated echo curve.

Abstract: A cable terminal for electrical connection of a wire to a component. The cable terminal (3) includes a first part (6) and a second part (7). A first part (6) connects to the wire. A second part (7) includes a longitudinal and continuous slot (19) with a first section (8), adapted to the width of a screw head on a screw with which the cable terminal is to be fitted to the component, and a second section (10), adapted to the width of the screw's threaded section. In a first position the slot (19) can be passed over the screw head in the first section (8) so that the cable terminal (3) can be displaced in a direction along the slot so that the screw ends up in a second position in the second section (10). The second part (7) of the cable terminal includes a part (12) that forms a roof (13) positioned at least partly above the first section (8).

Abstract: Partitioning control of the wet end and dry end, by introducing estimates of physical properties such as dry weight: and percent ash at the wire, allows for machine direction (MD) controls to continue during loss of scanner measurements. A mathematical model estimates the controlled, variables, such as dry weight, basis weight, and ash percent at the wire, and these estimated values are then controlled. When scanner measurements resume, parameters in the model are recursively updated to compensate for any model errors and ensure an accurate model. MD controls consist of a cascade set-up where the estimated wire-dry weight or wire basis weight and estimated wire ash percent are controlled by manipulating stock flow and addition of filler to stock. When scanner measurements are available, they become the downstream variables in the cascade control and are controlled by manipulation of the setpoints for the estimated wire weight and ash.

Abstract: A method of level finding includes providing characteristics of a shape of a transmitted pulse in time domain launched onto a waveguide into a tank having at least one material therein, physical properties of the waveguide and real and imaginary dielectric characteristics of the material at a frequency of the pulse. A level finding algorithm having a coarse search and a fine search is implemented, where the coarse search minimizes a prediction error between an echo signal (echo curve y(k)) and a sampled pulse model echo p(k) to obtain an objective function J(k) in a vicinity of a minimum prediction error (k*). The fine search calculates at least one minimum or maximum using J(k) in the vicinity of k*. The minimum or the maximum corresponds to a level of the material or an interface involving the material.