Classifications

• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F18/00—Pattern recognition
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F2218/00—Aspects of pattern recognition specially adapted for signal processing
  • G06F2218/02—Preprocessing
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S707/00—Data processing: database and file management or data structures
  • Y10S707/99931—Database or file accessing
  • Y10S707/99933—Query processing, i.e. searching
  • Y10S707/99934—Query formulation, input preparation, or translation
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S707/00—Data processing: database and file management or data structures
  • Y10S707/99931—Database or file accessing
  • Y10S707/99933—Query processing, i.e. searching
  • Y10S707/99936—Pattern matching access
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S707/00—Data processing: database and file management or data structures
  • Y10S707/99941—Database schema or data structure
  • Y10S707/99943—Generating database or data structure, e.g. via user interface

Definitions

• TITLE PRE-PROCESSING INPUT DATA WITH OUTLIER VALUES FOR A SUPPORT VECTOR
• the present invention relates generally to the field of predictive system models More particularly, the present invention relates to preprocessing of input data so as to correct for different time scales, transforms, missing or bad data, and or time-delays prior to input to a support vector machine for either training of the support vector machine or operation of the support vector machine
• non-linear models may include neural networks and support vector machines (SVMs)
• a model is trained with training data, e g , historical data, in order to reflect salient attributes and behaviors of the phenomena being modeled
• training data e g
• sets of training data may be provided as inputs to the model, and the model output may be compared to corresponding sets of desired outputs
• the resulting error is often used to adjust weights or coefficients in the model until the model generates the correct output (within some error margin) for each set of training data
• the model is considered to be in "training mode" during this process
• the model may receive real-world data as inputs, and provide predictive output information which may be used to control the process or system or make decisions regarding the modeled phenomena It is desirable to allow for pre-processing of input data of predictive models (e g , non-linear models, including neural networks and support vector machines), particularly in the field of e-commerce
• Predictive models may be used for analysis, control, and decision making in many areas, including electronic commerce (1 e , e-commerce), e-marketplaces, financial (e g , stocks and/or bonds) markets and systems, data analysis, data mining, process measurement, optimization (e g , optimized decision making, real-time optimization), quality control, as well as any other field or domain where predictive or classification models may be useful and where the object being modeled may be expressed abstractly For example, quality control in commerce is increasingly important The control and reproducibi ty of quality is be the focus of many efforts For example, in Europe, quality is the focus of the ISO (International Standards Organization, Geneva, Switzerland) 9000 standards These rigorous standards provide for quality assurance in production, installation, final inspection, and testing of processes They also provide guidelines for quality assurance between a supplier and customer
• a common problem that is encountered in training support vector machines for prediction, forecasting, pattern recognition, sensor validation and/or processing problems is that some of the training/testing patterns may be missing, corrupted, and/or incomplete Prior systems merely discarded data with the result that some areas of the input space may not have been covered during training of the support vector machine
• these sensor readings are typically sampled electronically, entered by hand from gauge readings, and/or entered by hand from laboratory results It is a common occurrence in real-world problems that some or all of these readings may be missing at a given time It is also common that the various values may be sampled on different time intervals Additionally, any one value may be "bad" in the sense that after the value is entered, it may be determined by some method that a data item was, in fact, incorrect Hence, if a given set of data has missing values, and that given set of data is plotted in a table, the result may be a
• time scale is meant to refer to any aspect of the time- dependency of data
• input data to a support vector machine is generally required to share the same time scale to be useful This constraint applies to data sets used to train a support vector machine, l e , input to the SVM in training mode, and to data sets used as input for run-time operation of a support vector machine, e g , input to the SVM in run-time mode
• the time scale of the training data generally must be the same as that of the run-time input data to insure that the SVM behavior in run-time mode corresponds to the trained behavior learned in training mode
• one set of data may be taken on an hourly basis and another set of data taken on a quarter hour (I e , every fifteen minutes) basis In this case, for three out of every four data records on the quarter hour basis there will be no corresponding data from the hourly set Thus, the two data sets are differently synchronous, 1 e , have different time scales
• the data sample periods may be non-pe ⁇ odic, producing asynchronous data, while another data set may be periodic or synchronous, e g , hourly
• these two data sets may not be useful together as input to the SVM while their time-dependencies, l e , their time scales, differ
• one data set may have a "hole" in the data, as described above, compared to another set, l e , some data may be missing on one of the data sets
• the presence of the hole may be considered to be an asynchronous or anomalous time interval in the data set, and thus may be considered to have an asynchronous or inhomogeneous time scale
• two data sets may have two different respective time scales, e g , an hourly basis and a 15 minute basis
• the desired time scale for input data to the SVM may have a third basis, e g , daily
• a system and method are presented for preprocessing input data to a non-linear predictive system model based on a support vector machine
• the system model may utilize a support vector machine having a set of parameters associated therewith that define the representation of the system being modeled
• the support vector machine may have multiple inputs, each of the inputs associated with a portion of the input data
• the support vector machine parameters may be operable to be trained on a set of training data that is received from training data and/or a run-time system such that the system model is trained to represent the run-time system
• the input data may include a set of target output data representing the output of the system and a set of measured input data representing the system variables
• the target data and system variables may be reconciled by the preprocessor and then input to the support vector machine
• a training device may be operable to train the support vector machine according to a predetermined training algorithm such that the values of the support vector machine parameters are changed until the support vector machine comprises a stored representation of the run-time system
• the term "device"
• the system may include a data storage device for storing training data from the run-time system
• the support vector machine may operate in two modes, a run-time mode and a training mode In the run-time mode, run-time data may be received from the run-time system Similarly, in the training mode, data may be retrieved from the data storage device, the training data being both training input data and training output data
• a data preprocessor may be provided for preprocessing received (1 e , input) data in accordance with predetermined preprocessing parameters to output preprocessed data
• the data preprocessor may include an input buffer for receiving and storing the input data
• the input data may be on different time scales
• a time merge device may be operable to select a predetermined time scale and reconcile the input data so that all of the input data are placed on the same time scale
• An output device may output the reconciled data from the time merge device as preprocessed data
• the reconciled data may be used as input data to the system model, 1 e , the support vector machine
• a control device may control the data preprocessor to operate in either training mode or run-time mode.
• the preprocessor may be operable to process the stored training data and output preprocessed training data.
• a training device may be operable to train the support vector machine (in the training mode) on the training data in accordance with a predetermined training algorithm to define the model parameters on which the support vector machine operates.
• the preprocessor In the run-time mode, the preprocessor may be operable to preprocess run-time data received from the run-time system to output preprocessed run-time data. The support vector machine may then operate in the run-time mode, receiving the preprocessed input run-time data and generating a predicted output and/or control parameters for the run-time system.
• the data preprocessor may further include a pre-time merge processor for applying one or more predetermined algorithms to the received data prior to input to the time merge device.
• a post-time merge processor (e.g., part of the output device) may be provided for applying one or more predetermined algorithms to the data output by the time merge device prior to output as the processed data.
• the preprocessed data may then have selective delay applied thereto prior to input to the support vector machine in both the run-time mode and the training mode.
• the one or more predetermined algorithms may be externally input and stored in a preprocessor memory such that the sequence in which the predetermined algorithms are applied is also stored.
• the input data associated with at least one of the inputs of the support vector machine may have missing data in an associated time sequence.
• the time merge device may be operable to reconcile the input data to fill in the missing data.
• the input data associated with a first one or more of the inputs may have an associated time sequence based on a first time interval, and a second one or more of the inputs may have an associated time sequence based on a second time interval.
• the time merge device may be operable to reconcile the input data associated with the first one or more of the inputs to the input data associated with the second one or more of the inputs, thereby generating reconciled input data associated with the at least one of the inputs having an associated time sequence based on the second time interval.
• the input data associated with a first one or more of the inputs may have an associated time sequence based on a first time interval
• the input data associated with a second one or more of the inputs may have an associated time sequence based on a second time interval.
• the time merge device may be operable to reconcile the input data associated with the first one or more of the inputs and the input data associated with the second one or more of the inputs to a time scale based on a third time interval, thereby generating reconciled input data associated with the first one or more of the inputs and the second one or more of the inputs having an associated time sequence based on the third time interval.
• the input data associated with a first one or more of the inputs may be asynchronous, and the input data associated with a second one or more of the inputs may be synchronous with an associated time sequence based on a time interval.
• the time merge device may be operable to reconcile the asynchronous input data associated with the first one or more of the inputs to the synchronous input data associated with the second one or more of the inputs, thereby generating reconciled input data associated with the first one or more of the inputs, where the reconciled input data comprise synchronous input data having an associated time sequence based on the time interval.
• the input data may include a plurality of system input variables, each of the system input variables including an associated set of data.
• a delay device may be provided that may be operable to select one or more input variables after preprocessing by the preprocessor and to introduce a predetermined amount of delay therein to output a delayed input variable, thereby reconciling the delayed variable to the time scale of the data set.
• This delayed input variable may be input to the system model. Further, this predetermined delay may be determined external to the delay device.
• the input data may include one or more outlier values which may be disruptive or counter-productive to the training and/or operation of the support vector machine.
• the received data may be analyzed to determine any outliers in the data set. In other words ' , the data may be analyzed to determine which, if any, data values fall above or below an acceptable range.
• the outliers if any, may be removed from the data, thereby generating corrected input data. The removal of outliers may result in a data set with missing data, i.e., with gaps in the data.
• GUI graphical user interface
• a user or operator may view the received data set, i.e., to visually inspect the data for bad data points, i.e., outliers.
• the GUI may further provide various tools for modifying the data, including tools for "cutting" the bad data from the set.
• the detection and removal of the outiiers may be performed by the user via the GUI.
• the user may use the GUI to specify one or more algorithms which may then be applied to the data programmatically, i.e., automatically.
• a GUI may be provided which is operable to receive user input specifying one or more data filtering operations to be performed on the input data, where the one or more data filtering operations operate to remove and/or replace the one or more outlier values.
• the GUI may be further operable to display the input data prior to and after performing the filtering operations on the input data.
• the GUI may be operable to receive user input specifying a portion of said input data for the data filtering operations.
• the removed data may optionally be replaced, thereby "filling in” the gaps resulting from the removal of outlying data.
• Various techniques may be brought to bear to generate the replacement data, including, but not limited to, clipping, interpolation, extrapolation, spline fits, sample/hold of a last prior value, etc., as are well known in the art.
• the removed outliers may be replaced in a later stage of preprocessing, such as the time merge process described above.
• the time merge process will detect that data are missing, and operate to fill the gap.
• the preprocess may operate as a data filter, analyzing input data, detecting outliers, and removing the outliers from the data set.
• the filter parameters may simply be a predetermined value limit or range against which a data value may be tested. If the value falls outside the range, the value may be removed, or clipped to the limit value, as desired.
• the limit(s) or range may be determined dynamically, for example, based on the standard deviation of a moving window of data in the data set, e.g., any value outside a two sigma band for a moving window of 100 data points may be clipped or removed.
• the received input data may comprise training data including target input data and target output data
• the corrected data may comprise corrected training data which includes corrected target input data and corrected target output data
• the support vector machine may be operable to be trained according to a predetermined training algorithm applied to the corrected target input data and the corrected target output data to develop model parameter values such that the support vector machine has stored therein a representation of the system that generated the target output data in response to the target input data.
• the model parameters of the support vector machine may be trained based on the corrected target input data and the corrected target output data, after which the support vector machine may represent the system.
• the input data may comprise run-time data, such as from the system being modeled, and the corrected data may comprise reconciled run-time data.
• the support vector machine may be operable to receive the corrected run-time data and generate run-time output data.
• the run-time output data may comprise control parameters for the system which may be usable to determine control inputs to the system for run-time operation of the system. For example, in an e-commerce system, control inputs may include such parameters as advertisement or product placement on a website, pricing, and credit limits, among others.
• control inputs may include such parameters as advertisement or product placement on a website, pricing, and credit limits, among others.
• the run-time output data may comprise predictive output information for the system which may be usable in making decisions about operation of the system.
• the predictive output information may indicate a recommended shift in investment strategies, for example.
• the predictive output information may indicate production costs related to increased energy expenses, for example.
• the preprocessor may be operable to detect and remove and/or replace outlying data in an input data set for the support vector machine.
• Various embodiments of the systems and methods described above may thus operate to preprocess input data for a support vector machine to reconcile data on different time scales to a common time scale.
• Various embodiments of the systems and methods may also operate to remove and/or replace bad or missing data in the input data.
• the resulting preprocessed input data may then be used to train and/or operate a support vector machine.
• Figure 1 illustrates an exemplary computer system according to one embodiment of the present invention
• Figure 2 is an exemplary block diagram of the computer system illustrated in Figure 1, according to one embodiment of the present invention
• Figures 3A and 3B illustrate two embodiments of an overall block diagram of the system for both preprocessing data during the training mode and for preprocessing data during the run mode;
• Figures 4A and 4B are simplified block diagrams of two embodiments of the system of Figures 3 A and 3B ;
• Figure 5 is a detailed block diagram of the preprocessor in the training mode according to one embodiment
• Figure 6 is a simplified block diagram of the time merging operation, which is part of the preprocessing operation, according to one embodiment
• Figure 7A illustrates a data block before the time merging operation, according to one embodiment
• Figure 7B illustrates a data block after the time merging operation, according to one embodiment
• FIGS 8A-8C illustrate diagrammatic views of the time merging operation, according to various embodiments.
• Figure 9A-9C are flowcharts depicting various embodiments of a preprocessing operation
• Figures 10A-10F illustrate the use of graphical tools for preprocessing the "raw" data, according to various embodiments
• Figure 11 illustrates the display for the algorithm selection operation, according to one embodiment
• Figure 12 presents a se ⁇ es of tables and properties, according to one embodiment
• Figure 13 is a block diagram depicting parameters associated with various stages m process flow relative to a plant output, according to one embodiment
• Figure 14 illustrates a diagrammatic view of the relationship between the various plant parameters and the plant output, according to one embodiment
• Figure 15 illustrates a diagrammatic view of the delay provided for input data patterns, according to one embodiment
• Figure 16 illustrates a diagrammatic view of the buffer formation for each of the inputs and the method for generating the delayed input
• Figure 17 illustrates the display for selection of the delays associated with various inputs and outputs in the support vector machine, according to one embodiment
• Figure 18 is a block diagram for a variable delay selection, according to one embodiment, Figure 19 is a block diagram of the adaptive determination of the delay, according to one embodiment, Figure 20 is a flowchart depicting the time delay operation, according to one embodiment, Figure 21 is a flowchart depicting the run mode operation, according to one embodiment,
• Figure 22 is a flowchart for setting the value of the variable delay, according to one embodiment.
• Figure 23 is a block diagram of the interface of the run-time preprocessor with a distributed control system, according to one embodiment
• Figure 1 illustrates a computer system 1 operable to execute a support vector machine for performing modeling and/or control operations
• the computer system 1 may be any type of computer system, including a personal computer system, mainframe computer system, workstation, network appliance, Internet appliance, personal digital assistant (PDA), television system or other device
• PDA personal digital assistant
• the term "computer system” can be broadly defined to encompass any device having at least one processor that executes instructions from a memory medium
• the computer system 1 may include a display device operable to display operations associated with the support vector machine
• the display device may also be operable to display a graphical user interface for process or control operations
• the graphical user interface may comprise any type of graphical user interface, e g , depending on the computing platform
• the computer system 1 may include a memory med ⁇ um(s) on which one or more computer programs or software components according to one embodiment of the present invention may be stored
• the memory medium may store one or more support vector machine software programs (support vector machines) which are executable to perform the methods described herein
• the memory medium may store a programming development environment application used to create, train, and/or execute support vector machine software programs
• the memory medium may also store operating system software, as well as other software for operation of the computer system
• the term "memory medium” is intended to include an installation medium, e g , a CD-ROM, floppy disks, or tape device, a computer system memory or random access memory such as DRAM, SRAM, EDO RAM, Rambus RAM, etc , or a non-volatile memory such as a magnetic media, e g , a hard drive, or optical storage
• the memory medium may comprise other types of memory as well, or combinations thereof
• the memory medium may be located in a first computer m which the programs ate executed, or may be located in a second different computer which connects to the first computer over a network, such as the Internet In the latter instance, the second computer may provide program instructions to the first computer for execution
• the term "support vector machine” refers to at least one software program, or other executable implementation (e g , an FPGA), that implements a support vector machine as described herein
• the support vector machine software program may be executed by a processor, such as in a computer system
• Figure 2 is an exemplary block diagram of the computer system illustrated in Figure 1, according to one embodiment It is noted that any type of computer system configuration or architecture may be used m conjunction with the system and method described herein, as desired, and Figure 2 illustrates a representative PC embodiment It is also noted that the computer system may be a general purpose computer system such as illustrated in Figure 1, or other types of embodiments The elements of a computer not necessary to understand the present invention have been omitted for simplicity
• the computer system 1 may include at least one central processing unit or CPU 2 which is coupled to a processor or host bus 5
• the CPU 2 may be any of various types, including an x86 processor, e g , a Pentium class, a PowerPC processor, a CPU from the SPARC family of RISC processors, as well as others
• Main memory 3 is coupled to the host bus 5 by means of memory controller 4
• the main memory 3 may store one or more computer programs or libraries according to the present invention
• the main memory 3 also stores operating system software as well as the software for operation of the computer system, as well known to those skilled in the art
• the host bus 5 is coupled to an expansion or input/output bus 7 by means of a bus controller 6 or bus bridge logic
• the expansion bus 7 is preferably the PCI (Peripheral Component Interconnect) expansion bus, although other bus types may be used
• the expansion bus 7 may include slots for various devices such as a video display subsystem 8 and hard drive 9 coupled to the expansion bus 7, among others (not shown)
• Classifiers generally refer to systems which process a data set and categorize the data set based upon prior examples of similar data sets, 1 e , training data
• the classifier system may be trained on a number of training data sets with known categorizations, then used to categorize new data sets
• classifiers have been determined by choosing a structure, and then selecting a parameter estimation algorithm used to optimize some cost function The structure chosen may fix the best achievable generalization error, while the parameter estimation algorithm may optimize the cost function with respect to the empirical risk
• the support vector method is a recently developed technique which is designed for efficient multidimensional function approximation
• the basic idea of support vector machines (SVMs) is to determine a classifier or regression machine which minimizes the empirical risk (1 e , the training set error) and the confidence interval (which corresponds to the generalization or test set error), that is, to fix the empirical risk associated with an architecture and then to use a method to minimize the generalization error
• SVMs as adaptive models for binary classification and regression is that they provide a classifier with minimal VC (Vapmk- Chervonenkis) dimension which implies low expected probability of generalization errors
• SVMs may be used to classify linearly separable data and nonhnearly separable data
• SVMs may also be used as nonlinear classifiers and regression machines by mapping the input space to a high dimensional feature space In this high dimensional feature space, linear classification may be performed
• a canonical hyperplane is a hype ⁇ lane (in this case we consider the optimal hyperplane) in which the parameters are normalized in a particular manner
• nonlinear classifier Consider (20) which is a linear classifier
• a nonlinear classifier may be obtained using support vector machines as follows
• the classifier is obtained by the inner product x, ⁇ x where I c S, the set of support vectors
• I c S the set of support vectors
• a kernel function may operate as a basis function for the support vector machine
• the kernel function may be used to define a space within which the desired classification or prediction may be greatly simplified
• kernel functions including
• a multilayer network may be employed as a kernel function as follows We have
• K(x bulkx) ⁇ ( ⁇ ( x, ⁇ x) + ⁇ ) (26) where ⁇ is a sigmoid function
• a high-dimensional "tube” with a radius of acceptable error is constructed which minimizes the error of the data set while also maximizing the flatness of the associated curve or function
• the tube is an envelope around the fit curve, defined by a collection of data points nearest the curve or surface, I e , the support vectors
• support vector machines offer an extremely powerful method of obtaining models for classification and regression They provide a mechanism for choosing the model structure in a natural manner which gives low generalization error and empirical risk
• a support vector machine may be built by specifying a kernel function, a number of inputs, and a number of outputs
• some type of training process may be used to capture the behaviors and/or attributes of the system or process to be modeled
• the modular aspect of one embodiment of the present invention may take advantage of this way of simplifying the specification of a support vector machine Note that more complex support vector machines may require more configuration information, and therefore more storage
• all that is required for the support vector machine is that the support vector machine be able to be trained and retrained so as to provide needed predicted values
• the coefficients used in a support vector machine may be adjustable constants which determine the values of the predicted output data for given input data for any given support vector machine configuration
• Support vector machines may be superior to conventional statistical models because support vector machines may adjust these coefficients automatically
• support vector machines may be capable of building the structure of the relationship (or model) between the input data and the output data by adjusting the coefficients
• a conventional statistical model typically requires the developer to define the equat ⁇ on(s) in which adjustable constant(s) are used
• the support vector machine may build the equivalent of the equat ⁇ on(s) automatically
• the support vector machine may be trained by presenting it with one or more training set(s)
• the one or more training set(s) are the actual history of known input data values and the associated correct output data values
• the newly configured support vector machine is usually initialized by assigning random values to all of its coefficients
• the support vector machine may use its input data to produce predicted output data These predicted output data values may be used in combination with training input data to produce error data These error data values
• Support vector machines may be superior to computer statistical models because support vector machines do not require the developer of the support vector machine model to create the equations which relate the known input data and training values to the desired predicted values (1 e , output data) In other words, a support vector machine may learn relationships automatically during training
• the support vector machine may require the collection of training input data with its associated input data, also called a training set
• the training set may need to be collected and properly formatted
• the conventional approach for doing this is to create a file on a computer on which the support vector machine is executed
• creation of the training set may be done automatically, using historical data This automatic step may eliminate errors and may save time, as compared to the conventional approach Another benefit may be significant improvement in the effectiveness of the training function, since automatic creation of the training set(s) may be performed much more frequently
• the time-dependence, 1 e , the time resolution and/or synchronization, of training and/or real-time data may not be consistent, due to missing data, variable measurement chronologies or timelines, etc
• the data may be preprocessed to homogenize the timing aspects of the data, as described below It is noted that in other embodiments, the data may be dependent on a different independent variable than time It is contemplated that the techniques described herein regarding homogemzation of time scales are applicable to other scales (1 e , other independent variables), as well
• Figure 3A is an overall block diagram of the data preprocessing operation in both the training mode and the run-time mode
• Figure 3B is a diagram of the data preprocessing operation of Figure 3A, but with an optional delay process included for reconciling time-delayed values in a data set
• Figure 3A shows, in the training mode, one or more data files 10 may be provided (however, only one data file 10 is shown) The one or more data
• the one or more data files 10 may be input to a preprocessor 12 that may function to perform various preprocessing functions, such as determining bad or missing data, reconciling data to replace bad data or fill in missing data, and performing various algorithmic or logic functions on the data, among others Additionally, the preprocessor 12 may be operable to perform a time merging operation, as described below During operation, the preprocessor 12 may be operable to store various preprocessing algorithms in a given sequence in a storage area 14 (noted as preprocess algorithm sequence 14 in Figure 3) As described below, the sequence may define the way in which the data are manipulated in order to provide the overall preprocessing operation
• the preprocessed data may be input into a training model 20, as Figure 3A shows
• the training model 20 may be a non-linear model (e g , a support vector machine) that receives input data and compares it with target output data Any of va ⁇ ous training algorithms may be used to train the support vector machine to generate a model for predicting the target output data from the input data
• the training model may utilize a support vector machine that is trained on one or more of multiple training methods
• Various weights within the support vector machine may be set during the training operation, and these may be stored as model parameters in a storage area 22
• the training operation and the support vector machine may be conventional systems
• the training model 20 and the runtime system model 26 may be the same system model operated in training mode and runtime mode, respectively In other words, when the support vector machine is being trained, l e , is in training mode, the model may be considered to be a training model, and when the support vector machine is in runtime mode, the model
• a Distributed Control System (DCS) 24 may be provided that may be operable to generate va ⁇ ous system measurements and control settings representing system variables (e g , temperature, flow rates, etc ), that comprise the input data to the system model
• the system model may either generate control inputs for control of the DCS 24 or it may provide a predicted output, these being conventional operations which are well known in the art
• the control inputs may be provided by the run-time system model 26, which has an output 28 and an input 30, as shown
• the input 30 may include the preprocessed and, in the embodiment of Figure 3B, delayed, data and the output may either be a predictive output, or a control input to the DCS 24 In the embodiments of Figures 3A and 3B, this is illustrated as control inputs 28 to the DCS 24
• the run-time system model 26 is shown as utilizing the model parameters stored in the storage area 22 It is noted that the run-time system model 26 may include a representation learned during the training operation, which representation was learned on the preprocessed data, l e
• the output data of the DCS 24 may be input to a run-time process block 34, which may be operable to process the data in accordance with the sequence of preprocessing algorithms stored in the storage area 14, which are generated during the training operation in one embodiment, the output of the run-time processor 34 may be input to a run-time delay process 36 to set delays on the data in accordance with the delay settings stored in the storage area 18 This may provide the overall preprocessed data output on the line 30 input to the run-time system model 26
• the preprocessed data may optionally be input to a delay block 16, as shown in Figure 3B
• a flow meter output may provide data at time to at a given value
• a given change in flow resulting in a different reading on the flow meter may not affect the output for a predetermined delay ⁇
• this flow meter output must be input to the support vector machine at a delay equal to ⁇ This may be accounted for in the training of the support vector machine through the use of the delay block 16
• the time scale of the data may be reconciled with the time scale of the system or process as follows
• the delay block 16 may be operable to set the various delays for different sets of data This operation may be performed on both the target output data and the input training data
• the delay settings may be stored in a storage area 18 (noted as delay settings 18 in Figure 3)
• the output of the delay block 16 may be input to the training model 20
• the blocks 'set delay' 16, 'delay settings' 18, and 'runtime delay' 36 may be omitted, and therefore, the outputs from the preprocessor 12 and the runtime process 34 may be fed into the training model 20 and the runtime system model 26, respectively, as shown in Figure 3A
• the delay process, as implemented by the blocks 'set delay' 16, 'delay settings' 18, and 'runtime delay' 36 may be considered as part of the data preprocessor 12
• the introduction of delays into portions of the data may be considered to be reconciling the input data to the time scale of the system or process being modeled, operated, or controlled
• Figure 4A is a simplified block diagram of the system of Figure 3A, wherein a single preprocessor 34' is utilized, according to one embodiment
• Figure 4B is a simplified block diagram of the system of Figure 3B, wherein the delay process, I e , a single delay 36', is also included, according to one embodiment
• the output of the preprocessor 34' may be input to a single system model 26'
• the preprocessor 34' and the system model 26' may operate in both a training mode and a run-time mode
• a multiplexer 35 may be provided that receives the output from the data file(s) 10 and the output of the DCS 24, and generates an output including operational variables, e g , plant or process variables, of the DCS 24
• the output of the multiplexer may then be input to the preprocessor 34'
• a control device 37 may be provided to control the multiplexer 35 to select either a training mode or a run-time mode In the training mode, the data file(s) 10 may have the output thereof
• control device 37 may place the system in a run-time mode such that the preprocessor 34' is operable to apply the algorithm sequence in the storage area 14 to the data selected by the multiplexer 35 from the DCS 24 After the algorithm sequence is applied, the data may be output to the system model 26' which may then operate in a predictive mode to either predict an output or to predict/determine control inputs for the DCS 24.
• the optional delay process 36' and settings 18' may be included, i.e., the data may be delayed, as shown in Figure 4B.
• the data may be output to the delay block 36', which may introduce the various delays in the storage area 18, and then these may be input to the system model 26' which may then operate in a predictive mode to either predict an output or to predict/determine control inputs for the DCS 24.
• the output of the delay 36' may be input to the single system model 26'.
• the delay 36' may be controlled by the control device 37 to determine the delay settings for storage in the storage area 18, as shown.
• FIG. 5 is a more detailed block diagram of the preprocessor 12 utilized during the training mode, according to one embodiment.
• the central operation may be a time merge operation (or a merge operation based on some other independent variable), represented by block 40.
• a pre-time merge process may be performed, as indicated by block 42.
• the data may be subjected to a post-time merge process, as indicated by block 44.
• the output of the post-time merge process block 44 may provide the preprocessed data for input to the delay block 16, shown in Figures 3B and 4B, and described above.
• a controller 46 may be included for controlling the process operation of the blocks 40- 44, the outputs of which may be input to the controller 46 on lines 48.
• the controller 46 may be interfaced with a functional algorithm storage area 50 through a bus 52 and a time merge algorithm 54 through a bus 56.
• the functional algorithm storage area 50 may be operable to store various functional algorithms that may be mathematical, logical, etc., as described below.
• the time merge algorithm storage area 54 may be operable to contain various time merge formats that may be utilized, such as extrapolation, interpolation or a boxcar method, among others.
• a process sequence storage area 58 may be included that may be operable to store the sequence of the various processes that are determined during the training mode. As shown, an interface to these stored sequences may be provided by a bi-directional bus 60.
• the controller 46 may determine which of the functional algorithms are to be applied to the data and which of the time merge algorithms are to be applied to the data in accordance with instructions received from an operator input through an input/output device 62.
• the process sequence in the storage area 58 may be utilized to apply the various functional algorithms and time merge algorithms to input data, for use in operation or control of the realtime system or process.
• Figure 6 is a simplified block diagram of a time merge operation, according to one embodiment. All of the input data x(t) may be input to the time merge block 40 to provide time merge data x D (t) on the output thereof. Although not shown, the output target data y(t) may also be processed through the time merge block 40 to generate time merged output data y'(t). Thus, in one embodiment, input data x(t) and/or target data y(t), may be processed through the time merge block 40 to homogenize the time-dependence of the data.
• input data x(v) and/or target data y(v) may be processed through the merge block 40 to homogenize the dependence of the data with respect to some other independent variable v (i.e., instead of time t).
• v independent variable
• dependence of the data on time t is assumed, however, the techniques are similarly applicable to data which depend on other variables
• the time-merge operation may comprise a transform that takes one or more columns of data, x,(t,), such as that shown in Figure 7A, with n, time samples at times t,' That is, the time-merge operation may comprise a function, ⁇ , that produces a new set of data ⁇ x' ⁇ on a new time scale t' from the given set of data x(t) sampled at t
• This function may be performed via any of a variety of conventional extrapolation, te ⁇ olation, or box-car algorithms (among others)
• An example representation as a C-language callable function is shown below
• Figure 8A shows a data table with bad, missing, or incomplete data
• the data table may consist of data with time disposed along a vertical scale and the samples disposed along a horizontal scale Each sample may include many different pieces of data, with two data intervals illustrated It is noted that when the data are examined for both the data sampled at the time interval "1" and the data sampled at the time interval "2", that some portions of the data result in incomplete patterns This is illustrated by a dotted line 63, where it may be seen that some data are missing in the data sampled at time interval "1” and some data are missing in time interval "2"
• a complete support vector machine pattern is illustrated in box 64, where all the data are complete Of interest is the time difference between the data sampled at time interval " 1" and the data sampled at time interval "2” In time interval "1", the data are essentially present for all steps in time, whereas data sampled at time interval "2" are only sampled periodically relative to data sampled at time interval "1”
• a data reconciliation procedure may be implemented that may fill
• the support vector machine based models that are utilized for time-series prediction and control may require that the time-interval between successive training patterns be constant Since the data generated from real- world systems may not always be on the same time scale, it may be desirable to time-merge the data before it is used for training or running the support vector machine based model To achieve this time-merge operation, it may be necessary to extrapolate, interpolate, average, or compress the data in each column over each time-region so as to give input values x'(t) that are on the appropriate time-scale All of these operations are referred to herein as "data reconciliation"
• the reconciliation algorithm utilized may include linear estimates, spline-fit, boxcar algorithms, etc If the data are sampled too frequently in the time-interval, it may be necessary to smooth or average the data to generate samples on the desired time scale This may be done by window averaging techniques, sparse-sample techniques or spline techniques, among others
• x'(t) is a function of all or a portion of the raw values
• X'(t) f( Xl( tN ) ⁇ Xl( tN )• Xn( tn )> Xli tN l )> Xl( tN l ) ( ⁇ Q
• Equation 30 Polynomial, spline-fit or support vector machine extrapolation techniques may use Equation 30, according to one embodiment
• training of the support vector machine may actually use interpolated values, I e , Equation 31, wherein the case of inte ⁇ olation, t N > t
• Figure 8B illustrates one embodiment of an input data pattern and target output data pattern illustrating the preprocess operation for both preprocessing input data to provide time merged output data and also preprocessing the target output data to provide preprocessed target output data for training pu ⁇ oses
• the data input x(t) may include a vector with many inputs, X ⁇ (t), X 2 (t), x n (t) > eacn of which may be on a different time scale It is desirable that the output x'(t) be extrapolated or interpolated to insure that all data are present on a single time scale For example, if the data at X](t) were on a time scale of one sample every second, represented by the time
• one set of data may be taken on an hourly basis and another set of data taken on a quarter hour (1 e , every fifteen minutes) basis, thus, for three out of every four data records on the quarter hour basis there will be no corresponding data from the hourly set
• These areas of missing data must be filled in to assure that all data are presented at commonly synchronized times to the support vector machine
• the time scales of the two data sets must be the same, and so must be reconciled.
• the data sample periods may be non-periodic, producing asynchronous data, while another data set may be periodic or synchronous, e g , hourly, thus, their time scales differ
• the asynchronous data may be reconciled to the synchronous data
• one data set may have a "hole" in the data, as desc ⁇ bed above, compared to another set, 1 e , some data may be missing in one of the data sets The presence of the hole may be considered to be an asynchronous or anomalous time interval in the data set, which may then require reconciliation with a second data set to be useful with the second set.
• two data sets may have two different respecnve time scales, e.g., an hourly basis and a 15 minute basis.
• the desired time scale for input data to the SVM may have a third basis, e.g., daily
• the two data sets may need to be reconciled with the third timeline prior to being used as input to the SVM
• Figure 8C illustrates one embodiment of the time merge operation Illustrated are two formatted tables, one for the set of data x x (t) and x 2 (t), the second for the set of data x (t) and x' 2 (t).
• the data set for x,(t) is illustrated as being on one time scale and the data set for x 2 (t) is on a second, different time scale.
• one value of the data set X ⁇ .(f) is illustrated as being bad, and is therefore "cut" from the data set, as described below.
• the preprocessing operation fills in, l e., replaces, this bad data and then time merges the data, as shown.
• the time scale for xj(t) is utilized as a time scale for the time merge data such that the time merge data x' ⁇ (t) is on the same time scale with the "cut" value filled in as a result of the preprocessing operation and the data set x 2 (t) is processed in accordance with one of the time merged algorithms to provide data for x' 2 (t) and on the same time scale as the data x' ⁇ (t).
• Figure 9A is a high level flowchart depicting one embodiment of a preprocessing operation for preprocessing input data to a support vector machine It should be noted that in other embodiments, various of the steps may be performed in a different order than shown, or may be omitted. Additional steps may also be performed
• the preprocess may be initiated at a start block 902 Then, in 904, input data for the support vector machine may be received, such as from a run-time system, or data storage The received data may be stored in an input buffer
• the support vector machine may comprise a non-linear model having a set of model parameters defining a representation of a system.
• the model parameters may be capable of being trained, 1 e , the SVM may be trained via the model parameters or coefficients.
• the input data may be associated with at least two inputs of a support vector machine, and may be on different time scales relative to each other. In the case of missing data associated with a single input, the data may be considered to be on different timescales relative to itself, in that the data gap caused by the missing data may be considered an asynchronous portion of the data.
• the scales of the input data may be based on a different independent variable than time
• one time scale may be asynchronous
• a second time scale may be synchronous with an associated time sequence based on a time interval
• both time scales may be asynchronous.
• both time scales may be synchronous, but based on different time intervals
• this un-preprocessed input data may be considered "raw" input data
• a desired time scale (or other scale, depending on the independent variable) may be determined
• a synchronous time scales represented in the data (if one exists) may be selected as the desired time scale
• a predetermined time scale may be selected
• the input data may be reconciled to the desired time scale
• the input data stored in the input buffer of 904 may be reconciled by a time merge device, such as a software program, thereby generating reconciled data
• a time merge device such as a software program
• all of the input data for all of the inputs may be on the same time scale
• the merge device may reconcile the input data such that all of the input data are on the same independent variable scale
• the time merge device may be operable to reconcile the input data to fill in the missing data, thereby reconciling the gap in the data to the time scale of the data set
• the input data associated with first one or more of the inputs may have an associated time sequence based on a first time interval, and a second one or more of the inputs may have an associated time sequence based on a second time interval
• the time merge device may be operable to reconcile the input data associated with the first one or more of the inputs to the input data associated with the second one or more other of the inputs, thereby generating reconciled input data associated with the first one or more of the inputs having an associated time sequence based on the second time interval
• the input data associated with a first one or more of the inputs may have an associated time sequence based on a first time interval
• the input data associated with a second different one or more of the inputs may have an associated time sequence based on a second time interval
• the time merge device may be opei ble to reconcile the input data associated with the first one or more of the inputs and the input data associated with the second one or more of the inputs to a time scale based on a third time interval, thereby generating reconciled input data associated with the first one or more of the inputs and the second one or more of the inputs having an associated time sequence based on the third time interval
• the input data associated with a first one or more of the inputs may be asynchronous
• the input data associated with a second one or more of the inputs may be synchronous with an associated time sequence based on a time interval
• the time merge device may be operable to reconcile the asynchronous input data to the synchronous input data, thereby generating reconciled
• the received input data of 904 may comprise training data which includes target input data and target output data
• the reconciled data may comprise reconciled training data which includes reconciled target input data and reconciled target output data which are both based on a common time scale (or other common scale)
• the support vector machine may be operable to be trained according to a predetermined training algorithm applied to the reconciled target input data and the reconciled target output data to develop model parameter values such that the support vector machine has stored therein a representation of the system that generated the target output data in response to the target input data
• the model parameters of the support vector machine may be trained based on the reconciled target input data and the reconciled target output data, after which the support vector machine may represent the system
• the input data of 904 may comprise run-time data, such as from the system being modeled, and the reconciled data of 908 may comprise reconciled run-time data
• the support vector machine may be operable to receive the run-time data and generate run-time output data
• the run-time output data may comprise control parameters for the system
• the control parameters may be usable to determine control inputs to the system for run-time operation of the system
• control inputs may include such parameters as advertisement or product placement on a website
• the run-time output data may comp ⁇ se predictive output information for the system
• the predictive output information may be usable in making decisions about operation of the system
• the predictive output information may indicate a recommended shift in investment strategies, for example
• the predictive output information may indicate production costs related to increased energy expenses, for example
• Figure 9B is a high level flowchart depicting another embodiment of a preprocessing operation for preprocessing input data to a support vector machine
• va ⁇ ous of the steps may be performed in a different order than shown, or may be omitted Additional steps may also be performed
• the input data may include one or more outlier values which may be disruptive or counterproductive to the training and/or operation of the support vector machine
• the preprocess may be initiated at a start block 902 Then, in 904, input data for the support vector machine may be received, as described above with reference to Figure 9A, and may be stored in an input buffer
• the received data may be analyzed to determine any outliers in the data set
• the data may be analyzed to determine which, if any, data values fall above or below an acceptable range
• the outliers may be removed from the data, thereby generating corrected input data
• the removal of outliers may result in a data set with missing data
• a graphical user interface may be included whereby a user or operator may view the received data set
• the GUI may thus provide a means for the operator to visually inspect the data for bad data points, l e , outliers
• the GUI may further provide various tools for modifying the data, including tools for "cutting" the bad data from the set
• the detection and removal of the outliers may be performed by the user via the GUI
• the user may use the GUI to specify one or more algo ⁇ thms which may then be applied to the data programmatically, l e , automatically
• a GUI may be provided which is operable to receive user input specifying one or more data filtering operations to be performed on the input data, where the one or more data filtering operations operate to remove and/or replace the one or more outlier values
• the GUI may be further operable to display the input data prior to and after performing the filtenng operations on the input data
• the GUI may be operable to receive user input specifying a portion of said input data for the data filtering operations Further details of the GUI are provided below with reference to Figures 10A-10F
• the removed data may optionally be replaced, as indicated in 911
• the preprocessing operation may "fill in” the gap resulting from the removal of outlying data
• Various techniques may be brought to bear to generate the replacement data, including, but not limited to, clipping, inte ⁇ olation, extrapolation, spline fits, sample/hold of a last prior value, etc , as are well known
• the removed outliers may be replaced in a later stage of preprocessing, such as the time merge process described above. In this embodiment, the time merge process will detect that data are missing, and operate to fill the gap.
• the preprocess may operate as a data filter, analyzing input data, detecting outliers, and removing the outliers from the data set.
• the filter parameters may simply be a predetermined value limit or range against which a data value may be tested. If the value falls outside the range, the value may be removed, or clipped to the limit value, as desired.
• the limit(s) or range may be determined dynamically. For example, in one embodiment, the range may be determined based on the standard deviation of a moving window of data in the data set, e.g., any value outside a two sigma band for a moving window of 100 data points may be clipped or removed.
• the data filter may also operate to replace the outlier values with more appropriate replacement values.
• the received input data of 904 may comprise training data including target input data and target output data
• the corrected data may comprise corrected training data which includes corrected target input data and corrected target output data
• the support vector machine may be operable to be trained according to a predetermined training algorithm applied to the corrected target input data and the corrected target output data to develop model parameter values such that the support vector machine has stored therein a representation of the system that generated the target output data in response to the target input data.
• the model parameters of the support vector machine may be trained based on the corrected target input data and the corrected target output data, after which the support vector machine may represent the system.
• the input data of 904 may comprise run-time data, such as from the system being modeled, and the corrected data of 908 may comprise reconciled run-time data.
• the support vector machine may be operable to receive the corrected run-time data and generate run-time output data.
• the runtime output data may comprise control parameters for the system.
• the control parameters may be usable to determine control inputs to the system for run-time operation of the system. For example, in an e-commerce system, control inputs may include such parameters as advertisement or product placement on a website, pricing, and credit limits, among others.
• the run-time output data may comprise predictive output information for the system.
• the predictive output information may be usable in making decisions about operation of the system.
• the predictive output information may indicate a recommended shift in investment strategies, for example.
• the predictive output information may indicate production costs related to increased energy expenses, for example.
• the preprocessor may be operable to detect and remove and/or replace outlying data in an input data set for the support vector machine.
• Figure 9C is a detailed flowchart depicting one embodiment of the preprocessing operation. In this embodiment, the preprocessing operations described above with reference to Figure 9A and 9B are both included.
• the flow chart may be initiated at start block 902 and then may proceed to a decision block 903 to determine if there are any pre-time merge process operations to be performed. If so, the program may proceed to a decision block 905 to determine whether there are any manual preprocess operations to be performed. If so, the program may continue along the "Yes" path to a function block 912 to manually preprocess the data In the manual preprocessing of data 912, the data may be viewed in a desired format by the operator and the operator may look at the data and eliminate, "cut", or otherwise modify obviously bad data values
• this data value may be "cut" such that it is no longer present in the data set and thereafter appears as missing data
• This manual operation is in contrast to an automatic operation where all values may be subjected to a predetermined algorithm to process the data
• an algorithm may be generated or selected that either cuts out all data above/below a certain value or clips the values to a predetermined maximum/minimum
• the algorithm may constrain values to a predetermined range, either removing the offending data altogether, or replacing the values, using the various techniques desc ⁇ bed above, including clipping, interpolation, extrapolation, splines, etc
• the clipping to a predetermined maximum/minimum is an algorithmic operation that is desc ⁇ bed below
• the program may proceed to a decision block 914 It is noted that if the manual preprocess operation is not utilized, the program may continue from the decision block 905 along the "No" path to the input of decision block 914
• the decision block 914 may be operable to determine whether an algorithmic process is to be applied to the data If so, the program may continue along a "Yes" path to a function block 916 to select a particular algorithmic process for a given set of data
• the program may proceed to a function block 918 to apply the algorithmic process to the data and then to a decision block 920 to determine if more data are to be processed with the algorithmic process If so, the program may flow back around to the input of the function block 16 along a "Yes" path, as shown
• the program may flow along a "No" path from decision block 920 to a function block 922 to store the sequence of algorithmic processes such that each data set has the desired algorithmic processes applied there
• the program may continue along the "Yes" path from the decision block 930 to a function block 932 to select the algorithmic process and then to a function block 934 to apply the algorithmic process to the desired set of data and then to a decision block 936 to determine whether additional sets of data are to be processed in accordance with the algorithmic process If so, the program may flow along the "Yes' path back to the input of function block 932, and if not, the program may flow along the "No" path to a function block 938 to store the new sequence of algorithmic processes with the sequence and then the program may proceed to a DONE block 1000 If the post time merge process is not to be performed, the program may flow from the decision block 930 along the "No" path to the DONE block 1000 Referring now to Figures 10A-10E, there are illustrated embodiments of three plots of data.
• FIGS 10A- 10E also illustrate one embodiment of a graphical user interface (GUI) for various data manipulation reconciliation operations which may be included in one embodiment of the present invention. It is noted that these embodiments are meant to be exemplary illustrations only, and are not meant to limit the application of the invention to any particular application domain or operation.
• GUI graphical user interface
• each figure includes one plot for an input "tempi”, one plot for an input "press2" and one plot for an output "ppm”, as may relate to a chemical plant.
• the first input may relate to a temperature measurement
• the second input may relate to a pressure measurement
• the output data may correspond to a parts per million variation.
• the tempi data there are two points of data 108 and 110, which need to be "cut” from the data, as they are obviously bad data points. Such data points that lie outside the acceptable range of a data set are generally referred to as "outliers". These two data points appear as cut data in the data-set, as shown in Figure 10C, which then may be filled in or replaced by the appropriate time merge operation utilizing extrapolation, interpolation, or other techniques, as desired.
• the data preprocessor may include a data filter which may be operable to analyze input data, detect outliers, and remove the outliers from the data set.
• the applied filter may simply be a predetermined value limit or range against which a data value may be tested. If the value falls outside the range, the value may be removed, or clipped to the limit value, as desired.
• the limit(s) or range may be determined dynamically. For example, in one embodiment, the range may be determined based on the standard deviation of a moving window of data in the data set, e.g., any value outside a two sigma band for a moving window of 100 data points may be clipped or removed.
• the filter may replace any removed outliers using any of such techniques as extrapolation and interpolation, among others.
• the removed outliers may be replaced in a later stage of processing, such as the time merge process described herein.
• the time merge process will detect that data are missing, and operate to fill the gaps.
• Figure 10A shows the raw data.
• Figure 10B shows the use of a cut data region tool 115.
• Figure 10B shows the points 108 and 110 highlighted by dots showing them as cut data points. In one embodiment of the GUI presented on a color screen, these dots may appear in red.
• Figure 10D shows a vertical cut of the data, cutting across several variables simultaneously. Applying this cut may cause all of the data points to be marked as cut, as shown in Figure 10E.
• Figure 10F flowcharts one embodiment of the steps involved in cutting or otherwise modifying the data.
• a region of data may be selected by a set of boundaries 112 (in Figure 10D), which results may be utilized to block out data. For example, if it were determined that data during a certain time period were invalid due to various reasons, these data may be removed from the data sets, with the subsequent preprocessing operable to fill in the "blocked" or "cut” data.
• the data may be displayed as illustrated in Figures 10A-10E, and the operator may select various processing techniques to manipulate the data via various tools, such as cutting, clipping and viewing tools 107, 111, 113, that may allow the user to select data items to cut, clip, transform or otherwise modify.
• various tools such as cutting, clipping and viewing tools 107, 111, 113, that may allow the user to select data items to cut, clip, transform or otherwise modify.
• the mode for removing data this may be referred to as a manual manipulation of the data.
• algorithms may be applied to the data to change the value of that data.
• the data may be rearranged in the spreadsheet format of the data.
• the operator may view the new data as the operation is being performed.
• the user may be provided the ability to utilize a graphic image of data in a database, manipulate the data on a display in accordance with the selection of the va ⁇ ous cutting tools, and modify the stored data in accordance with these manipulations
• a tool may be utilized to manipulate multiple variables over a given time range to delete all of that data from the input database and reflect it as "cut" data
• the data set may then be considered to have missing data, which may require a data reconciliation scheme in order to replace this data in the input data stream
• the data may be "clipped", that is, a graphical tool may be utilized to determine the level at which all data above (or below) that level is modified All data in the data set, even data not displayed, may be modified to this level This in effect may constitute applying an algorithm to that data set
• Figure 10F the flowchart depicts one embodiment of an operation of utilizing the graphical tools for cutting data
• An initiation block, data set 117 may indicate the acquisition of the data set
• the program may proceed from decision block 119 along a "Yes" path to decision block 133 to determine if the transformed data are to be saved If not, the program may proceed along an "No" path to "DONE" block 135 If the transformed data are to be saved, the program may continue from the decision block 133 along the "Yes" path to a function block 137 to transform the data set and then to the "DONE" block 135
• FIG 11 is a diagrammatic view of a display (1 e , a GUI) for performing algorithmic functions on the data, according to one embodiment
• the display may include a first numerical template 114 which may provide a numerical keypad function
• a window 116 may be provided that may display the va ⁇ able(s) that is/are being operated on The variables that are available for manipulation may be displayed in a window 118
• the va ⁇ ous variables are arranged in groups, one group associated with a first date and time, e g , variables tempi and press 1, and a second group associated with a second date and time, e g , variables temp2 and press2, for example, prior to time merging
• a mathematical operator window 120 may be included that may provide various mathematical operators (e g , "+", "-”, etc ) which may be applied to the variables
• Various logical operators may also be available in the window 120 (e g , "AND”, “OR”, etc )
• a functions window 122 may be included that may allow selection of va
• variable tempi may be selected to be processed and the logarithmic function selected for application thereto
• the variable tempi may first be selected from window 118 and then the logarithmic function "log" selected from the window 122
• the left parenthesis may then be selected from window 120, followed by the selection of the variable tempi from window 118, then followed by the selection of the right parenthesis from window 120.
• This may result in the selection of an algorithmic process which includes a logarithm of the variable tempi.
• This may then be stored as a sequence, such that upon running the data through the run-time sequence, data associated with the variable tempi has the logarithmic function applied thereto prior to inputting to the run-time system model 26. This process may be continued or repeated for each desired operation.
• the resultant data may be as depicted in Table 1, as shown in Figure 12. It may be seen in Table 1 that there is a time scale difference, one group associated with the time TIME_1 and one group associated with the time TIME_2. It may be seen that the first time scale is based on an hourly interval and that the second time scale is based on a two hour interval. Any "cut" data (not shown) would appear as missing data.
• variable tempi is processed by taking a logarithm thereof. This may result in a variation of the set of data associated with the variable tempi. This is illustrated in Table 2, as shown in Figure 12.
• the sequence of operations associated therewith may determine the data that were cut out of the original data set for data tempi and also the algorithmic processes associated therewith, these being in a sequence which is stored in the sequence block 14 and which may be examined via a data-column properties module 113, shown in Figures 10A-10E, as illustrated in Properties 2, of Figure 12.
• the operator may select the time merge function 115, illustrated in Figure 10B, and may specify the time scale and type of time merge algorithm. For example, in Figure 10B, a one-hour time- scale is selected and the box-car algorithm of merging is used.
• the time scale may be disposed on an hourly interval with the time merge process. This is illustrated in Table 3 of Figure 12, wherein all of the data are on a common time scale and the cut data has been extrapolated to insert new data.
• the sequence after time merge may include the data that are cut from the original data sets, the algorithmic processes utilized during the pre-time merge processing, and the time merge data. This is illustrated in Properties 3, as shown in Figure 12.
• the display of Figure 11 may again be pulled up, and another algorithmic process selected.
• One example may be to take the variable tempi after time merge and add a value of 5000 to this variable. This may result in each value in the column associated with the variable tempi being increased by that value, as illustrated by the data in Table 4 of Figure 12.
• the sequence may then be updated using the sequence presented in Properties 4, as shown in Figure 12.
• Figure 13 is a block diagram of one embodiment of a process flow, such as, for example, a process flow through a plant.
• a process flow such as, for example, a process flow through a plant.
• operation and control of a plant is an exemplary application of one embodiment of the present invention, any other process may also be suitable for application of the systems and methods described herein, including scientific, medical, financial, stock and/or bond management, and manufacturing, among others.
• the flow meter 130 may provide a variable output flowl.
• the flow may continue to a process block 132, wherein various plant processes may be carried out.
• Various plant inputs may be provided to this process block 132.
• the flow may then continue to a temperature gauge 134, which may output a variable tempi.
• the flow may proceed to a process block 136 to perform other plant processes, these also receiving plant inputs.
• the flow may then continue to a pressure gauge 138, which may output a variable pressl.
• the flow may continue through various other process blocks 139 and other parameter measurement blocks 140, resulting in an overall plant output 142 which may be the desired plant output.
• Figure 14 is a timing diagram illustrating the various effects of the output variables from the plant and the plant output, according to one embodiment.
• the output variable flowl may experience a change at a point 144.
• the output variable tempi may experience a change at a point 146
• the variable pressl may experience a change at a point 148.
• the corresponding change in the output may not be time synchronous with the changes in the variables.
• changes in the plant output may occur at points 150, 152 and 154, for the respective changes in the variables at points 144-148, respectively.
• the change between points 144 and 150 and the variable flowl and the output, respectively may experience a delay D2.
• the change in the output of point 152 associated with the change in the variable tempi may occur after delay D3.
• the change in the output of point 154 associated with the change in the variable pressl may occur after a delay of Dl. In accordance with one embodiment of the present invention, these delays may be accounted for during training, and/or during the run-time operation.
• Figure 16 is a diagrammatic view of the method for implementing the delay, according to one embodiment.
• variable length buffers may be provided in each data set after preprocessing, the length of which may correspond to the longest delay. Multiple taps may be provided in each of the buffers to allow various delays to be selected.
• Each of the buffers has a length of N, such that the first buffer outputs the delay input X ⁇ D ( , the second buffer 158 outputs the delay input x 2D (t), and the third buffer 160 outputs the delay input x 3D (t).
• the buffer 162 has a delay tap that may provide for a delay of "n-1" to provide an output X 4 o(t).
• Figure 17 illustrates one embodiment of a display that may be provided to the operator for selecting the various delays to be applied to the input variables and the output variables utilized in training.
• a delay for the variable tempi of -4.0, -3.5, and -3.0 three separate input variables have been selected for input to the training model 20
• three separate outputs are shown as selected, one for delay 0.0, one for a delay 0.5, and one for a delay of 1 0 to predict present and future values of the variable
• Each of these may be processed to vary the absolute value of the delays associated with the input variables.
• Figure 18 is a block diagram of one embodiment of a system for generating process dependent delays
• a buffer 170 is illustrated having a length of N, which may receive an input variable x' n (f) from the preprocessor 12 to provide on the output thereof an output xicide D (t) as a delayed input to the training model 20.
• a multiplexer 172 may be provided which has multiple inputs, one from each of the n buffer registers with a ⁇ -select circuit 174 provided for selecting which of the taps to output The value of ⁇ may be a function of other variables parameters such as temperature, pressure, flow rates, etc.
• the temperature relationship may be placed in the block 174 and then the external parameters input and the value of ⁇ utilized to select the various taps input to the multiplexer 172 for output therefrom as a delay input.
• the system of Figure 18 may also be utilized in the run-time operation wherein the various delay settings and functional relationships of the delay with respect to the external parameters are stored in the storage area 18 The external parameters may then be measured and the value of ⁇ selected as a function of this temperature and the functional relationship provided by the information stored in the storage area 18 This is to be compared with the training operation wherein this information is externally input to the system.
• FIG. 17 is a block diagram of one embodiment of a preprocessing system for setting delay parameters, where the delay parameters may be learned. For simplicity, the preprocessing system is not illustrated, rather, a table 176 of the preprocess data is shown.
• the delay may be achieved by a time delay adjustor 178, which may utilize the stored parameters in a delayed parameter block 18'.
• the delay parameter block 18' is similar to the delay setting block 18, with the exception that absolute delays are not contained therein Rather, information relating to a window of data may be stored in the delay parameter block 18'
• the time delay adjustor 178 may be operable to select a window of data within each set of data in the table 176, the data labeled through x ' perennial.
• the time delay adjustor 178 may be operable to receive data within a defined window associated with each of the sets of data x' ⁇ -x' n and convert this information into a single value for output therefrom as an input value IN ⁇ -IN n
• a system model 26' which system model 26' is similar to the run-time system model 26 and the training model 20 in that it is realized with a non-linear model (e g., a support vector machine)
• the non-linear model is illustrated as having an input layer 179, a middle layer 180 and an output layer 182.
• the middle layer 180 may be operable to map the input layer 179 to the output layer 182, as described below. However, note that this is a non-linear mapping function.
• the time delay adjustor 178 may be operable to linearly map each of sets of data x' l -x' n in the table 176 to the input layer 179 This mapping function may be dependent upon the delay parameters in the delay parameter block 18' As desc ⁇ bed below, these parameters may be learned under the control of a learning module 183, which learning module 183 may be controlled during the support vector machine training in the training mode It is similar to that desc ⁇ bed above with respect to Figure 4
• the learning module 183 may be operable to control both the time delay adjustor block 178 and the delay parameter block 18' to change the values thereof in training of the system model 26'
• target outputs may be input to the output layer 182 and a set of training data input thereto in the form of the chart 176, it being noted that this is already preprocessed in accordance with the operation as desc ⁇ bed above
• the model parameters of the system model 26' stored in the storage area 22 may then be adjusted in accordance with a predetermined training algorithm to minimize the error
• the error may only be minimized to a certain extent for a given set of delays Only by setting the delays to their optimum values may the error be minimized to the maximum extent Therefore, the learning module 183 may be operable to vary the parameters in the delay parameter block 18' that are associated with the timing delay adjustor 178 in order to further minimize the error
• Figure 20 is a flowchart illustrating the determination of time delays for the training operation, according to one embodiment
• This flowchart may be initiated at a time delay block 198 and may then continue to a function block 200 to select the delays In one embodiment, this may be performed by the operator as desc ⁇ bed above with respect to Figure 17
• the program may then continue to a decision block 202 to determine whether variable ⁇ are selected
• the program may continue along a "Yes" path to a function block 204 to receive an external input and vary the value of ⁇ in accordance with the relationship selected by the operator, this being a manual operation in the training mode
• the program may then continue to a decision block 206 to determine whether the value of ⁇ is to be learned by an adaptive algorithm If variable ⁇ are not selected in the decision block 202, the program may then continue around the function block 204 along the "No" path
• the program may continue from the decision block 206 to a function block 208 to learn the value of ⁇ adaptively The program may then proceed to a function block 210 to save the value of ⁇ If no adaptive learning is required, the program may continue from the decision block 206 along the "No" path to function block 210
• the model 20 may be trained, as indicated by a function block 212 and then the parameters may be stored, as indicated by a function block 214 Following storage of the parameters, the program may flow to a DONE block 216
• Figure 21 is a flowchart depicting operation of the system in run-time mode, according to one embodiment
• the operation may be initiated at a run block 220 and may then proceed to a function block 222 to receive the data and then to a decision block 224 to determine whether the pre-time merge process is to be entered If so, the program may proceed along a "Yes" path to a function block 226 to preprocess the data with the stored sequence and then to a decision block 228 If not, the program may continue along the "No" path to the input of decision block 228 Decision block 228 may determine whether the time merge operation is to be performed If so, the program may proceed along the "Yes" path to function block 230 to time merge with the stored method and then to the input of a decision block 232 and, if not, the program may continue along the "No" path to the decision block 232
• the decision block 232 may determine whether the post-time merge process is to be performed If so, the program may proceed along the "Yes" path to a function block 234 to process the data with
• Data may be initially output by the DCS 24 during run-time
• the data may then be preprocessed in the preprocess block 34 in accordance with the preprocess parameters stored in the storage area 14
• the data may then be delayed in the delay block 36 in accordance with the delay settings set in the delay block 18, this delay block 18 may also receive the external block control input, which may include parameters on which the value of ⁇ depends to provide the variable setting operation that was utilized during the training mode
• the output of the delay block 36 may then be input to a selection block 260, which may receive a control input
• This selection block 260 may select either a control support vector machine or a prediction support vector machine
• a predictive system model 262 may be provided and a control model 264 may be provided, as shown Both models 262 and 264 may be identical to the training model 20 and may utilize the same parameters, that is, models 262 and 264 may have stored therein a representation of the system that was trained in the training model 20
• the predictive system model 262 may provide on the output thereof predictive outputs, and the
• a predictive support vector machine may operate in a run-time mode or in a training mode with a data preprocessor for preprocessing the data prior to input to a system model
• the predictive support vector machine may include an input layer, an output layer and a middle layer for mapping the input layer to the output layer through a representation of a run-time system
• Training data derived from the training system may be stored in a data file, which training data may be preprocessed by a data preprocessor to generate preprocessed training data, which may then be input to the support vector machine and trained in accordance with a predetermined training algorithm
• the model parameters of the support vector machine may then be stored in a storage device for use by the data preprocessor in the run-time mode
• run-time data may be preprocessed by the data preprocessor in accordance with the stored data preprocessing parameters input during the training mode and then this preprocessed data may be input to the support vector machine, which support vector machine may operate in a prediction mode In the prediction mode

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