IMAGE READING SYSTEMS, METHODS AND STORAGE MEDIUM FOR PERFORMING GEOMETRIC EXTRACTION
20260080707 ยท 2026-03-19
Assignee
Inventors
- Soumitri Naga Kolavennu (Plymouth, MN, US)
- Ankur Tomar (Minneapolis, MN, US)
- Varshini Sriram (Minneapolis, MN, US)
- Rodolfo Carriedo Roque (Apple Valley, MN, US)
- Lavanya Basavaraju (Minneapolis, MN, US)
- Bryan Lee Stuhlsatz (Merrifield, MN, US)
Cpc classification
G06V10/778
PHYSICS
G06V30/18086
PHYSICS
G06V30/414
PHYSICS
International classification
G06V30/414
PHYSICS
G06V10/50
PHYSICS
G06V10/778
PHYSICS
Abstract
Geometric extraction is performed on an unstructured document by recognizing textual blocks on at least a portion of a page of the unstructured document, generating bounding boxes that surround and correspond to the textual blocks, determining search paths having coordinates of two endpoints and connecting at least two bounding boxes, and generating a graph representation of the at least a portion of the page, the graph representation including the plurality of textual blocks, the coordinates of the vertices of each bounding box and the coordinates of the two endpoints of each search path.
Claims
1. A method for processing a document having one or more pages, comprising: receiving an unstructured document at a document receiving device; generating an initial graph representation of at least a portion of the unstructured document, the initial graph representation including textual blocks, bounding boxes surrounding the textual blocks, and search paths connecting the bounding boxes; generating a confidence level score for the initial graph representation based on geometric characteristics of the textual blocks and bounding boxes; reviewing the generated graph representation to identify errors based on subject matter context of the unstructured document; when an error is identified, regenerating the graph representation by recognizing textual blocks on the at least a portion of the unstructured document, generating bounding boxes for the recognized textual blocks, determining search paths connecting the generated bounding boxes, and generating a regenerated graph representation; and the process continuing for multiple iterations until the confidence level score is above a threshold confidence level score.
2. The method of claim 1, wherein the review of the generated graph representation is performed by: analyzing textual content of the textual blocks based on subject matter context of the unstructured document; evaluating associations between textual blocks for consistency with the subject matter context; and determining whether there is any error in any search path or textual block association.
3. The method of claim 1, wherein the confidence level score is generated based on: geometric characteristics of the bounding boxes and textual blocks; and correspondence scores generated based on training data.
4. The method of claim 1, further comprising: storing, in a database, the regenerated graph representation along with one or more corrections for the identified errors; and using the one or more corrections for the identified errors as training data to train a machine learning kernel.
5. The method of claim 1, further comprising: providing a training dataset comprising a plurality of unstructured documents to a machine learning kernel; for each document in the training dataset, generating bounding boxes surrounding textual blocks using a machine learning model, determining mean character distances between characters within textual blocks, detecting textual blocks where the mean character distance meets a threshold, combining closely related words into single textual blocks based on n-grams and wordnet collections, and determining orientation-related information of the bounding boxes; establishing search paths based on the detected orientation-related information, wherein bounding boxes aligned to a right side of a document are connected by a vertical search path and bounding boxes aligned to a bottom of the document are connected by a horizontal search path; providing a testing dataset to the machine learning kernel to test performance; and the threshold set more precise over time after training.
6. The method of claim 5, wherein combining closely related words comprises: using the machine learning model to learn a character set of documents; combining sequences of characters into words; identifying email addresses and phone numbers; and declaring each identified email address and phone number as a single textual block.
7. The method of claim 5, further comprising: the machine learning model trained to recognize center aligned, left aligned, and right aligned textual arrangements; generating overlapping bounding boxes wherein a single word is part of two bounding boxes; and storing alignment patterns in the training dataset.
8. The method of claim 1, wherein receiving the unstructured document comprises: receiving a physical document at the document receiving device; scanning the physical document to generate a digital image; performing optical character recognition on the digital image to convert printed text into machine-encoded text; segmenting the digital image into separate pages when the document comprises multiple pages; performing intra-page segmentation on each separate page; and storing the preprocessed document in a storage device.
9. The method of claim 8, wherein the optical character recognition process generates optical character recognition confidence scores for textual content, and further comprising: associating the optical character recognition confidence scores with corresponding textual blocks; combining the optical character recognition confidence scores with geometric analysis confidence scores to generate combined confidence scores; and identifying textual blocks having combined confidence scores below a threshold for manual review.
10. The method of claim 1, further comprising: defining, in a semantic module, association types for textual blocks including one to one associations where one textual block is associated with only one other textual block, one to many associations where one textual block is associated with multiple textual blocks, and many to one associations where multiple textual blocks are associated with a single textual block; providing, to the semantic module, textual signatures representing semantic meanings, wherein textual signatures comprise spatial pyramids of characters that can be manifested in different formats; searching the graph representation along search paths to match textual signatures; and for one to many associations, grouping all first, second and other ordinal associations into a record.
11. The method of claim 10, wherein the textual signatures are provided using at least one of: regular expression string syntax; user-defined predicate functions; and enumerated lists of all possible values.
12. The method of claim 10, wherein searching the graph representation comprises: looking to a right search path of an entity for a match; if no match is found then looking to a bottom search path of the entity; and the search continuing for multiple matches even if a match has been established.
13. The method of claim 10, wherein the search direction is altered to user defined directions and comprises: specifying an order of search directions; performing reverse lookups by first identifying any textual entity having a specified signature and then searching for corresponding matching descriptions; and stopping the search after a finite number of comparisons.
14. The method of claim 1, further comprising: extracting data from the unstructured document using geometric extraction to identify target textual block pairs including title textual blocks and value textual blocks; generating a data extraction result comprising a document identifier, a data extraction time, an aggregated confidence score determined from individual confidence scores of each title value pair, extracted titles and corresponding values, and a selector configured to cause an operation when selected; the data extraction result displayed via an input-output interface; receiving, via the interface, a selection of the selector; the operation causing an original document to be opened via the interface for visual verification against the extraction result; the extraction result enabled to receive changes to any element; corrections entered into the extraction result read by a machine learning processor and used to train a model; and the training data stored in a database.
15. The method of claim 14, wherein retraining is initiated: on a periodic basis; or after a threshold number of corrections.
16. The method of claim 14, wherein the data extraction result further comprises: for at least one title having multiple values, displaying the title associated with a first value representing complete textual content and second and third values.
17. The method of claim 1, wherein determining search paths comprises: determining multiple potential search paths between bounding boxes, wherein the multiple potential search paths include at least one of: a diagonal search path and a nonlinear search path; and selecting a search path from among the multiple potential search paths, wherein the selected search path is not required to be a shortest search path.
18. The method of claim 1, further comprising: using a database configured to store data and accumulate additional data over time, the database comprising a training dataset for training machine learning models and a testing dataset for testing machine learning models; providing guidance on how to correct or adjust the graph representation based on review of the graph representation; using feedback from the review and corrections as training data to train a machine learning kernel over time for performing data extraction.
19. A system for document processing, comprising: a processor; a memory device coupled to the processor and storing a machine learning kernel; a database configured to store data and accumulate additional data over time, the database comprising a training dataset for training machine learning models and a testing dataset for testing machine learning models; a geometric analyzer coupled to the processor and configured to generate graph representations of documents; a descriptive linguistics analyzer coupled to the processor and configured to review graph representations generated by the geometric analyzer and provide guidance on how to correct or adjust the graph representation; and wherein the machine learning kernel is configured to receive feedback from the descriptive linguistics analyzer, use corrections as training data, and the machine learning kernel becomes better trained over time for performing data extraction.
20. A non-transitory computer-readable medium storing instructions that, when executed by one or more processors, cause the one or more processors to perform: generating an initial graph representation of a document; generating confidence scores for textual block associations in the graph representation; reviewing the generated graph representation to identify errors based on subject matter context of the document; regenerating the graph representation; the process continuing for multiple iterations until confidence scores are above a threshold; storing regenerated graph representations and identified corrections in a database as training data; retraining a machine learning kernel using the training data; providing a semantic module configured to define association types and textual signatures; searching the graph representation using the semantic module along user defined search directions; and generating data extraction results comprising aggregated confidence scores and a selector for visual verification.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
[0035] Various embodiments will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims.
[0036] This disclosure addresses problems of the prior art by introducing an image reading system, a control method for controlling an image reading system, and a storage medium having stored therein a control method for performing geometric extraction. In an example use case, the systems, methods, and computer products described herein perform computer-aided information extraction from generic form-like documents automatically without human intervention. Aspects of embodiments described herein provide artificial intelligence systems and methods that read these documents securely.
[0037] Form-like documents can vary. Examples of form-like documents include receipts, application forms, rental application forms, mortgage application forms, medical records, doctor prescriptions, restaurant menus, pay stubs, patent Application Data Sheets (ADS), trade documents, SEC filings (e.g., Form 10-K), company annual reports, company earnings reports, IRS tax forms (e.g., Form W-2, Form 1040, etc.), invoices, and bank statements. Some form-like documents like IRS tax forms are templatic, while other form-like documents such as company annual reports are non-templatic or multi-templatic. Aspects of the embodiments described herein are agnostic to the type of document.
[0038] A document can include one or more pages. Further, a document need not be a physical document. For example, a document may be an electronic document. An electronic document also may be in various formats such as Portable Document Format (PDF), spreadsheet format such as the Excel Open XML Spreadsheet (XLSX) file format, a webform such as HTML form that allows a user to enter data on a web page that can be sent to a server for processing. Webforms can resemble paper or database forms because web users fill out the forms using checkboxes, radio buttons, or text fields via web pages displayed in a web browser. An electronic document may be stored either on a local electronic device such as a mobile device, personal computer (PC), or on an online database accessible from the Internet.
[0039]
[0040] In the example of
[0041] In some embodiments, document receiving device 112 receives document 102. In cases where document 102 is a physical document, the document receiving device 112 may be a document intake mechanism that moves the document through the data extraction system 110. In cases where the document 102 is an electronic document, the document receiving device 112 may be a component that is configured to communicate with a sender of the document to receive the electronic document. For simplicity, document 102 is a one-page document unless otherwise indicated. It should be understood, however, that the example embodiments described herein are equally applicable to a multi-page document.
[0042] The received document 102 may be preprocessed by the data preprocessor 114 once it is received by the document receiving device 112. The data preprocessor 114 preprocess the received document 102 by carrying out one or more preprocessing steps that facilitate data extraction that occurs later. The preprocessing steps can include one or more of the following: (i) scanning; (ii) optical character recognition (OCR); (iii) page segmentation; (iv) intra-page segmentation; and (v) storing the preprocessed document.
[0043] The geometric analyzer 116 and descriptive linguistics analyzer 118 work together to recognize, extract and associate data from document 102. Generally, geometric analyzer 116 generates a graph representation of document 102 based on geometric characteristics of the document 102, whereas the descriptive linguistics analyzer 118 provides information on what specific information contained in the document are relevant. A graph representation, as used herein, is a mathematical structure used to model pairwise relations between objects. For example, a graph in this context can be made up of vertices (also called nodes or points) which are connected by edges (also called links or lines). Additionally, the descriptive linguistics analyzer 118 may also be used to review the graph representation generated by the geometric analyzer 116 and provide guidance on how to correct or adjust the graph representation, if necessary.
[0044] In some embodiments, geometric analyzer 116 and descriptive linguistics analyzer 118 are coupled to a machine learning kernel 126. Details of the geometric analyzer 116, the descriptive linguistics analyzer 118, and the machine learning kernel 126 are described below with reference to
[0045] In an example embodiment, the processing device 192 includes one or more central processing units (CPU). In other embodiments, the processing device 192 may additionally or alternatively include one or more digital signal processors, field-programmable gate arrays, or other electronic circuits as needed.
[0046] The memory device 194, coupled to a bus, operates to store data and instructions to be executed by processing device 192, geometric analyzer 116 and/or descriptive linguistics analyzer 118. The memory device 194 can be a random access memory (RAM) or other dynamic storage device. The memory device 194 also may be used for storing temporary variables (e.g., parameters) or other intermediate information during execution of instructions to be executed by processing device 192, geometric analyzer 116 and/or descriptive linguistics analyzer 118. As shown in
[0047] The storage device 196 may be a nonvolatile storage device for storing data and/or instructions for use by processing device 192, geometric analyzer 116 and/or descriptive linguistics analyzer 118. The storage device 196 may be implemented, for example, with a magnetic disk drive or an optical disk drive. In some embodiments, the storage device 196 is configured for loading contents of the storage device 196 into the memory device 194.
[0048] I/O interface 198 includes one or more components which a user of the data extraction system 110 can interact. The I/O interface 198 can include, for example, a touch screen, a display device, a mouse, a keyboard, a webcam, a microphone, speakers, a headphone, haptic feedback devices, or other like components.
[0049] The network access device 199 operates to communicate with components outside the data extraction system 110 over various networks. Examples of the network access device 199 include one or more wired network interfaces and wireless network interfaces. Examples of such wireless network interfaces of the network access device 199 include wireless wide area network (WWAN) interfaces (including cellular networks) and wireless local area network (WLANs) interfaces. In other implementations, other types of wireless interfaces can be used for the network access device 199.
[0050] The database 120 is configured to store data used by machine learning kernel 126, geometric analyzer 116, and/or descriptive linguistics analyzer 118. As shown in
[0051]
[0052] As shown in
[0053] Document 300 of
[0054] Referring again to
[0055] A textual block is text grouped together. Often, the text takes on the shape of a square or rectangular block however the embodiments described can operate on textual blocks having shapes other than a square or a rectangle. At operation 206, textual blocks in the unstructured document are recognized. In one implementation, textual blocks in the unstructured document are recognized by the geometric analyzer 116 of
[0056] In some embodiments, each term (e.g., a number, an alphanumerical, a word, or a group of words, a phrase, and the like) in the document may be used to generate a corresponding textual block 401. In other embodiments, two or more terms (e.g., Social Security Number) may be combined to form a single textual block 401. In some embodiments, sometimes one term corresponds to a textual block 401, and sometimes two or more terms correspond to a textual block 401.
[0057] At operation 208, a bounding box is generated for each of the textual blocks recognized at operation 206. A bounding box is a box surrounding its corresponding textual block. In some embodiments, a bounding box is rectangular. A bounding box may have other shapes as needed. As shown in
[0058] In one implementation, geometric information of bounding boxes 402 includes coordinates of multiple vertices of each bounding box 402. The origin of the coordinate plane may be chosen to be at a point that makes the coordinates of the multiple vertices capable of being expressed as values that can be stored in a memory. As in the example of
[0059] In other embodiments, for example where a bounding box is rectangular and extends either horizontally or vertically, geometric information of the bounding boxes 402 may include coordinates of the centroid of the bounding box, a width in the horizontal direction, and a height in the vertical direction.
[0060] In the example of
[0061] Referring again to
[0062] A search path is a plot, by a computer application, of route between two points. In some embodiments, a single search path is determined. In some embodiments, multiple potential search paths are determined. A search path can be a vertical search path or a horizontal search path. In some embodiments, a search path is a diagonal search path or a nonlinear search path (e.g., curved).
[0063] If more than one search path is determined, the search path that is selected to be used need not be the shortest search path. Indeed, it may be more accurate to select a search path longer than other search paths that have been determined.
[0064] Referring again to
[0065] In some implementations, operation 210 can be conducted using the machine learning kernel 126 of
[0066] As shown in the example of
[0067] At operation 212, a graph representation is generated. In some implementations, the graph representation includes information on the bounding boxes 402 and information on the search paths 502. In some examples, the information on the bounding boxes 402 may include coordinates of vertices of those bounding boxes 402, while the information on the search paths 502 may include coordinates of endpoints of those search paths 502.
[0068] Sometimes the initial generated graph representation is not ideal.
[0069] As shown in this example, in result A, Origination Date is recognized as a textual block 402-7 as a title, and Nov. 24, 2000 is recognized as a textual block 402-5 as its corresponding value; Chicago Sales is recognized as a textual block 402-8, and $600000.00 is recognized as a textual block 402-6 as its corresponding value. Result A seems reasonable if the context of the document 600 is, for example, a travel agency or the like.
[0070] In result B, Origination is recognized as a textual block 402-1 as a title, and Chicago is recognized as a textual block 402-2 as its corresponding value; Date is recognized as a textual block 402-3, and Nov. 24, 2000 is recognized as a textual block 402-5 as its corresponding value; Sales is recognized as a textual block 402-4, and $600000.00 is recognized as a textual block 402-6 as its corresponding value. Result B seems reasonable if the context of the document 600 is a bank statement or the like.
[0071] Therefore, geometric analyzer 116 of
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[0073] At operation 702, the generated graph representation is reviewed by the descriptive linguistics analyzer 118 of
[0074] A confidence level is the probability that the associations generated by the geometric extractor are related. The confidence level is generated by the machine learning kernel 126 based on the training data that the machine learning kernel 126 has either been trained or finetuned on. A linguistics analyzer can use machine learning kernels (e.g., recursive neural networks, transformers, and the like) to provide confidence scores on how two textual entities are related when they are part of a paragraph or a sentence. In some embodiments, the machine learning kernel combines both the linguistic analysis output learnings and geometric extractor output learnings to provide an overall confidence score on the associations.
[0075] At operation 704, the geometric analyzer 116 regenerates the graph representation. In other words, the geometric analyzer 116 may repeat operations 206, 208, 210, and 212 as shown in
[0076]
[0077] At operation 802, one or more target textual block pairs are obtained from the descriptive linguistics analyzer 118. In turn, at operation 804, the graph representation is searched along the search paths to identify the target textual block pairs. The identified target textual block pair(s) are then output, as shown at operation 806.
[0078] In some embodiments, searching the graph representation along the search paths to identify the target textual block pairs includes locating a first textual block, searching the graph representation, starting from the first textual block and along one of the plurality of horizontal search paths, and searching the graph representation, starting from the first textual block and along one of the plurality of vertical search paths. In an example implementation, the graph representation can be searched until a predetermined criterion is met. An example predetermined criterion can be, for example based on one of the target textual block pairs is identified. Thus searching the graph representation can be stopped after one of the target textual block pairs is identified.
[0079] In yet another example implementation, the predetermined criterion can be based on whether a first number of textual blocks have been searched. Thus, in this example embodiment, the searching of the graph representation is stopped after a first number of textual blocks have been searched.
[0080] In some embodiments, a semantic module can be used to define what needs to be searched or associated in the document. In some example use cases, the associations are one to one such that one textual block (e.g., SSN) is associated with only one other textual block (e.g., 999-99-9999). In some use cases one textual block (e.g., Grocery Items) is associated with multiple textual blocks (e.g., apples, potatoes, etc.). In other embodiments multiple textual blocks (Quarterly Sales, June 2020) are associated with a single text block (e.g., $120MM). These association possibilities are provided to semantic module at design stage of the extraction.
[0081] In yet another embodiment, for one to many associations, all first, second and other ordinal associations are grouped into a record.
[0082] A textual signature is a spatial pyramid of characters that represents the same semantic meaning. In some embodiments, one or more textual signatures of the different values (semantics) for an entity that can be manifested in a textual block are input to the semantic module. For example, a date could be represented in various textual signatures (mm/dd/yy or DAY of MONTH, YYYY). In addition, the textual signature may include different types of values. For example, an entity in a textual block can be composed of different parts where each part represents a distinct piece of information (e.g., social security numbers are of the form 999-99-9999, where the first set of three digits is the Area Number, the second set of two digits is called the Group Number and the final set of four digits is the Serial Number). In one embodiment, the textual signatures could be provided using the regular expression string syntax. In other embodiment, the textual signatures can be provided by user-defined predicate functions or small software modules. In a third embodiment, the textual signatures could simply be provided as an enumerated list of all possible values.
[0083] With the combination of the geometrically aligned textual blocks (i.e., the graph), their associated search paths (referred to as walks), the textual signatures of the entities, aspects of the embodiments being matching the textual signatures of blocks provided by the semantics module along the search paths. In some examples, the search path is to look to the right search path of an entity for a match and then to the bottom search path of the entity if a match is not found. The search can continue, for example, for multiple matches even if a match has been established. Alternatively, the search direction can be altered from the nominal (right and down) to user defined directions and the order of those direction. For example, the module could be instructed to look in the top search direction first and then to the left direction. This is useful for reverse lookups where first any textual entity that has the signature (for example, a date) is determined and then the corresponding matching description for the date (Maturity Date) is searched.
[0084] In yet another embodiment, a search can continue for a finite set of comparisons irrespective of if there is a match. For example, look only two blocks to the left and then stop searching.
[0085] In another embodiment, the search continues until a user defined stopping criterion is met. The stopping criterion normally is to stop when there are no more blocks along the search direction. However, another stopping criterion could be at first non-match of the signature. Another stopping criteria could be when finite number of matches has been reached.
[0086] Once the above search and match process is completed, the matched entities can be output for further processing.
[0087] As evident by the above detailed procedure, example embodiments can be used to extract and associate information from any form-like document. The association is made by the geometry and proximity of the entities. The extraction is not specific to any template. The extraction is resilient to changes in the template (for example, the module can extract the information whether the SSN: 999-99-9999 in the top right of the document or in the middle or at the bottom) or changes in the semantics of the template (if Social Security Number is spelled out as compared to abbreviated SSN).
[0088] The systems and methods described herein can be applied to any form-like documents. By increasing the semantic understanding of the various common terms in a specific domain it can be extended and quickly reused to extract form data from any domain. The geometric module-construction of the textual blocks, connections of the blocks and construction of the search paths along with the signatures for searching and association of the entities enable more accurate geometric extraction.
[0089] Depending on the textual sequence of the block (e.g., email vs. stock picks), the machine learning algorithm could continue the search path through multiple blocks or end after a finite number of blocks. The machine learning model is trained on a correspondence score of the content of each of the plurality of the textual blocks. The correspondence score could be trained using match to a regular expression pair, trained using the similarity of a language model (e.g., word2vec, contextual language model generated embeddings. For example, from ELMo, BERT, RoBERTa and others) or trained using a sequence-to-sequence neural networks that may use techniques such as RNNs or Transformers. Descriptive linguistic models can utilize the language representation of words and characters in spoken (prose-like) language A geometric analyzer can utilize geometric relationships between objects whether the objects are textual, pictorial or a combination. In some embodiments, the machine learning kernel 126 utilizes the training data to learn the correspondence between textual blocks utilizing combinations of both the geometric analyzer representations and the descriptive linguistic representations. Furthermore, the kernel also learns the appropriate geometric search paths along which the correspondence scores are most likely to be maximum.
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[0091] In an exemplary implementation, the data extraction result 1000 is a record of associations of the elements extracted from document 900. the data extraction result can include an identifier identifying the data extraction result, Document identifier (ID) 1002, and a time of data extraction, Data Extraction Time 1004. In an example embodiment, the data extraction result 1000 includes a confidence score 1008. As explained above, a confidence score 1008 is the probability that the associations generated by the geometric extractor are related. In some embodiments, a confidence score for each title: value pair is determined and all the confidence scores are aggregated for the unstructured document to generate the confidence score 1008 (also referred to as an aggregated confidence score 1008). In some embodiments each confidence score can be presented for individual correspondences (e.g., individual title: value pairs).
[0092] In some embodiments, the data extraction result 1000 generated by the data extraction system 110 is an electronic file. In an example implementation, the electronic file includes a selector which, when selected via an interface, operates to cause an operation to be performed. In the example shown in
[0093] In some embodiments, information fields are title: value pairs. In the example of
[0094] In some embodiments, the present disclosure includes a computer program product which is a non-transitory storage medium or computer-readable medium (media) having instructions stored thereon/in which can be used to program a computer to perform any of the processes of the present. Examples of the storage medium can include, but is not limited to, any type of disk including floppy disks, optical discs, DVD, CD-ROMs, microdrive, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of media or device suitable for storing instructions and/or data.
[0095] The foregoing description of embodiments of the present disclosure has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations will be apparent to the practitioner skilled in the art.
[0096] The various embodiments described above are provided by way of illustration only and should not be construed to limit the claims attached hereto. Those skilled in the art will readily recognize various modifications and changes that may be made without following the example embodiments and applications illustrated and described herein, and without departing from the true spirit and scope of the following claims.