Abstract:
The invention relates to a system and method of conducting surveillance of stolen vehicles. Stolen vehicle information is downloaded from a database to a central server. At the central server, vehicle information is parsed to the specific requirements. Each subscribing jurisdiction downloads its area-specific stolen vehicle database to a subscriber workstation, e.g., via the Internet or an intranet. Police cars have on-board mobile surveillance points having a camera and a processor. A copy of the area-specific stolen vehicle database is loaded into each car&#39;s processor. The mobile surveillance point reads license plates of vehicles in traffic, and the processor compares the license plates to stolen plate numbers stored in the database. The processor activates a signal to alert the officer. Stationary checkpoints located in the jurisdiction have a stationary surveillance point having a camera and a processor. The surveillance system stores images and creates a database of all vehicle plates in the area. The surveillance data is downloaded to the subscriber computer. The subscriber computer has a map database. A comparison algorithm identifies stolen vehicles in the area and their direction of travel, and displays the information on an area map. The analysis if performed with a spatial analysis algorithm along with temporal analysis using police officer&#39;s experience and knowledge of the area and vehicle types (make/model/value/etc) stolen. The police officer analyzes patterns of stolen vehicles and generates suggested new locations for checkpoints, narrowing in on a possible chop shop location.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   “The present application is a continuation of U.S. patent application Ser. No. 10/409,083, filed on Apr. 9, 2003 by inventors Andrew J. Bucholz, Patrick D. Minix and Matthew D. Roberts and claims the benefit of the filing date of that application.” 

   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Grant Number 2002-90606-VA-IJ awarded by the U.S. Department of Justice, Office of Justice Programs, National Institute of Justice. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates broadly to systems and methods of surveillance, and particularly to surveillance of vehicles. 
   2. Description of the Related Art 
   According to Bureau of Justice Statistics, U.S. Department of Justice, auto theft costs the nation close to eight billion dollars per year. Even without factoring in the cost of higher insurance rates, the victim&#39;s loss of productivity, the impact on legitimate auto parts vendors, manufacturers, mechanics, and the concurrent loss of tax revenue on those services and products, motor vehicle theft is the most expensive property crime in the United States. On-going efforts to address this crime drain our law enforcement system, insurance companies, and other economic resources. Of the 1.17 million automobiles stolen nation-wide in the year 2000, only 14 percent of these crimes were closed by arrest. 
   Both professional and non-professional thieves commit vehicle theft. The non-professional steals for joy riding, other criminal activity, and transportation. The vehicles stolen by the non-professional thieves are often damaged and usually recovered. Task forces and routine patrol are used to catch these thieves. These methods typically require officers to remember license plates and descriptions of stolen vehicles, identify the vehicle regardless of whether it is parked or being driven, recall the information, and pursue the vehicle. An officer cannot observe every, or even the majority of vehicles he or she passes while on patrol. Additionally, the officer must address other events while on patrol and cannot devote all time and effort on patrol to looking for stolen vehicles. 
   The professional thief steals vehicles for shipment out of the country via ports and to deliver to chop shops for resale of total vehicles and parts. Professional thieves commit roughly thirty five percent of all auto thefts. Chop-shops are defined as the process of disassembling autos and destroying or disguising the identity of the vehicle or its parts so that it can be resold. These vehicles are rarely recovered. Not recovering vehicles leaves law enforcement at a distinct disadvantage to obtain information and evidence necessary to solve the crimes. The primary tool for gathering information is the confidential informant. Based on information supplied by informants, law enforcement runs undercover operations to catch the thieves. This tool leaves law enforcement to solve the problem mostly from a reactive state, as they must rely on time and labor-intensive detective work, obtaining informants, and the motivation for the informants. 
   Part of finding the professional thief involves locating chop shops, where stolen vehicles are painted, given license plates, or otherwise altered to sell the vehicle, or taken apart to sell spare parts. Thousands of vehicles may be stolen in any jurisdiction over a year&#39;s time. Moreover, a vehicle is often stolen from one part of town, taken to a chop shop in another part of town and disassembled for parts, or loaded onto a container and sent overseas. Law enforcement does not have any available tool to analyze the stolen vehicle data. More particularly, there is additionally no tool available for using stolen vehicle data to help locate chop shops. 
   There is little assistance available to law enforcement to make arrests in motor vehicle theft cases and subsequently deter further thefts. The absence of tools for gathering and analyzing information about stolen vehicles severely limits the ability of law enforcement to deter, decrease, or prevent this criminal activity. Moreover, currently in 2002, there are approximately 19,000 police departments in the United States. Without a uniform system of gathering and analyzing stolen vehicle information, it is difficult for police departments to work together on such cases. 
   Some systems have previously been proposed. The use of cameras in law enforcement is well known. Basic image processing systems are used at tollbooths and traffic lights, and to record the license plate of a speeding vehicle. However, such systems treat the observed vehicle in isolation, and do not relate the vehicle to a previous activity record. These systems further do not use a mobile camera in the pursuit of detection of criminal offenses occurring in real time. Current systems do not take a proactive approach, as they catch offenders only after a minor crime (traffic violation) has been committed. The system also has to address the needs of law enforcement; it must be fast, invisible, and utilize timely data if it is to provide any needed service. 
   Although the current systems and methods function well for their provided task, the devices do not provide users with a comparison to existing stolen vehicle databases. These systems and methods do not provide spatial analysis for recognizing traffic patterns of stolen vehicles. Further, these systems and methods do not provide tools for catching both the professional and non-professional thief. 
   SUMMARY OF THE INVENTION 
   The present invention has been made in view of the above circumstances and has as an object to provide a system and method of conducting surveillance of stolen vehicles. Yet another objective of the present invention is to provide a surveillance system customized to each jurisdiction. Still another objective of the present invention is to link stolen vehicle information nation-wide. A further object of the invention is to analyze the patterns associated with stolen vehicles. Yet another objective of the present invention is to gather data about stolen vehicles. 
   Still another objective of the present invention is to automate vehicle surveillance. Yet another objective of the present invention is to identify stolen vehicles in real time. A further objective of the present invention is to assess a high number of vehicles in the stream of traffic for legitimacy. Still another objective of the present invention is to provide an automated surveillance system capable of reading the myriad of typeface and designs found on license plates in the United States. Yet another objective of the present invention is to conduct surveillance of either moving or stationary vehicles from either a moving or stationary surveillance point. 
   Another objective of the present invention is to identify probable chop shop locations. Yet another objective of the present invention is to aid in analyzing traffic patterns of stolen vehicles. Still another objective of the present invention is to provide a stolen vehicle surveillance system that can be used by police departments throughout the United States. 
   Another objective of the present invention is to provide a surveillance tool that provides evidence of criminal activity that is admissible in a court of law. 
   The invention relates to a system and method of conducting surveillance of stolen vehicles. Stolen vehicle information is downloaded from U.S. Government, State, or local databases to a central server. At the central server, vehicle information is parsed to the specific packages. Each subscribing jurisdiction downloads its area-specific stolen vehicle database to a subscriber workstation, e.g., via the Internet or an intranet. Police cars have on-board mobile surveillance points having a camera and a processor. A copy of the area-specific stolen vehicle database is loaded into each car&#39;s processor. The mobile surveillance point reads license plates of vehicles in traffic, and the processor compares the license plates to stolen plate numbers stored in the database. The processor activates a signal to alert the officer. Stationary checkpoints located in the jurisdiction have a stationary surveillance point having a camera and a processor. The surveillance system stores images and creates a database of all vehicle plates in the area. The surveillance data is downloaded to the subscriber computer. The subscriber computer has a map system which compares stolen vehicle records to identify un-recovered stolen vehicles in the area and their direction of travel, and displays the information on an area map. The analysis process is a spatial analysis of similar criminal methods of operation (mo), vehicle types, values, time of day, general location. The system displays data using filters and sorting tools. The spatial analysis is done visually by the investigator over a map display. The spatial analysis generates suggested new locations for checkpoints, narrowing in on a possible chop shop location. 
   Additional objects and advantages of the invention will be set forth in part in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of this specification illustrate some embodiments of the invention and, together with the description, serve to explain the objects, advantages, and principles of the invention. In the drawings, 
       FIG. 1  illustrates a system architecture in accordance with an exemplary embodiment of the present invention. 
       FIG. 2  illustrates a mobile surveillance point in accordance with an exemplary embodiment of the present invention. 
       FIG. 3  illustrates a stationary surveillance point in accordance with an exemplary embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A preferred embodiment of the present invention is shown in  FIGS. 1–3 .  FIG. 1  illustrates the system architecture of the present invention.  FIGS. 1 and 2  illustrate the system and method used for both professional and non-professional thieves.  FIGS. 1 and 3  illustrate the system and method used for locating professional thieves. 
   One aspect of the present invention is a system and method of conducting surveillance to detect stolen vehicles. The system is run and maintained at a service center  10 . System subscribers, such as police departments and other law enforcement agencies, register with the service center  10 . Subscribers register with the service center  10  via e-mail, phone, fax, or web site, or any such other method. Subscribers provide information about their jurisdiction, such as geographic location, known criminal activity, when shift changes occur. 
   The service center  10  has a central server  12 . Storage, memory, and processing capabilities needed to operate the server are based on number of subscribers; a minimum ability of Pentium class processor, 20 gigabyte hard drive, 128 mega-byte modem. A secure communications link  3  connects the central server  12  to a database  2  of all vehicles reported stolen in the jurisdiction of interest, such as the United States. The National Crime Information Center, or NCIC, maintains the database  2  of all vehicles reported stolen in the United States. The database  2  includes the make and model of the car, the Vehicle Identification Number, or VIN, the color, license plate number, the reporting agency, and date the vehicle was stolen. Other databases that NCIC maintains that could also be used by this system are: the stolen tag file and felony vehicle file. 
   The central server  12  includes logic, e.g., software, a processor, and memory, to automatically access the NCIC database  2 , and update and store a resident copy of a stolen vehicle database  14 . The central server  12  stores instructions to optimize data from the stolen vehicle database  14  by parsing out data specific to each jurisdiction and function of each subscriber. The central server  12  additionally stores instructions for formatting the NCIC data. Data is formatted for several purposes: 1) to reduce false alarms and speed response time by reducing the target set to likely stolen vehicles based on geography and time, 2) to merge data from several sources into a single package for simple distribution to field offices, 3) to clean up the data, address errors, remove recovered vehicles, etc. Other functions performed at the service center are; back-up, analysis tools, security, administration, accounting, and customer service. 
   Subscribers have a subscriber computer  20 ,  22 ,  24 . The subscriber computer  20 ,  22 ,  24  has a processor and memory (not shown), an I/O, or input/output device  21 ,  23 ,  25 , a monitor  27 ,  33 ,  39 , a printer,  150 ,  151 ,  152 , criminal database  26 ,  30 ,  36  and mapping program  28 ,  32 ,  38 , and spatial analysis software  29  stored in computer memory. In the preferred embodiment, the I/O device  21 ,  23 ,  25  is a disc drive capable of reading and writing to a data transfer device  40 ,  42 ,  44 . In the preferred embodiment, the data transfer device  40 ,  42 ,  44  is a compact flashcard. However, it will be appreciated that a variety of portable, hard-wired, or wireless data transfer mediums maybe used. For example, CD ROMs, diskettes, zip drives, and the like, as well as ribbon cables or modems may be used without departing from the scope of the present invention. 
   As illustrated in  FIG. 1 , any number of subscribers, up to an arbitrary number N, participate in the system. The subscriber computer  20 ,  22 ,  24  connects to the central server  12  via a secure communications link  5 . NCIC security protocols will have to be followed to access information with the National Law Enforcement Telecommunications System&#39;s (NLETS) secure network as a preferred method. The communication link  5  may be wired or wireless provided that sufficient security precautions, such as encryption, are used with wireless systems. The I/O device  21 ,  23 ,  25  connect mobile  50  and stationary  52  surveillance points to the surveillance system of the present invention. The spatial analysis software  29  contains instructions for reading the geographic location of each stationary surveillance point  50 ,  52 , for comparing surveillance data to the regional theft database  26 , mapping the location of observed stolen vehicles, and displaying mapped stolen vehicles and their direction of travel. One of ordinary skill in the art of computer programming would be able to write such a software program with detailed software design plan, access to U.S. Government database structure, and support from subject matter expert is required. The spatial analysis software resides on the subscriber computer  20 ,  22 ,  24 . Additionally, the comparing of the image data to the stolen vehicle database and to the mapping database is done by the multiple software programs. 
   Referring to  FIGS. 1 and 2 , a mobile surveillance point  50  is fixed to a police car  500 . The mobile surveillance point  50  has camera unit  60  with standard interface, an Ethernet display unit  90 , processor unit  70  electrically connected with PCI Buses and a discrete power unit  100 . It will be appreciated by one skilled in the art, however, that a variety of electronic connectors may be used without departing from the scope of the present invention. 
   The camera unit  60  has a camera  62 , optics  64 , bracket  66 , and alignment mechanism  68 . The camera unit is mounted on or in the police car  500  with the bracket  66  and positioned with the alignment mechanism  68 . In the preferred embodiment, the mounting bracket is a flat swivel with a manual lock and handle for panning, the alignment mechanism  68  includes a discrete encoder that reports out the angle settings to the processor. However, it will be appreciated by one skilled in the art that a wide variety of moveable devices can be used to change the position of the camera  62 . The alignment mechanism will be mechanically operated with electrical read-out. 
   The camera  62  is a high-resolution camera that can clearly process the images of fast-moving vehicles in daytime, nighttime, and inclement weather conditions. Specifically, the camera should operate at temperatures between 0.degree. C. to 50.degree. C. and a non-condensing humidity of 0% to 80%. Other camera specifications are, preferably, power consumption of 250 Watts, the EMC/EMI emissions meet the FCC class B rating of under 6 dB, the I/O capability is 24 channel, TTL compatible with digital I/O per I/O module, the CPU has at least a 233 MHz processor, Interfaces for RS-232, RS-422, Ethernet, NTCIP and TCP/IP, and Image Capture Modules for 4 black and white inputs and real-time JPEG format with digital high-resolution. Commercially available high-resolution cameras that operate within the specifications include the RS-170 manufactured by Ball Aerospace of Boulder, Colo., and the NTSC and PAL cameras manufactured by Sony Corporation. The camera  62  processes digital images of license plates on vehicles captured by the optics  64  as they pass through the optics  64  field of view. Image data is transmitted from the camera  62  to the processor unit  70  through a PCI/ISA bus (not shown). 
   The optics  64  are attached to the camera  62  and used to enhance the basic capability of the camera  62  to capture images of vehicle license plates which my vary by vendor or users with the goal to work with as many cameras as possible. The optics  64  have at least a high-resolution lens. However, additional lenses, filters, or both may be used in combination in order to change the type and clarity of the images. For example, infrared optics may be used to add vision for night, if desired. 
   The processor unit  70  of the mobile surveillance point  50  includes an enclosure contained in the police car  500 , e.g., in the trunk. The processor unit  70  has a user interface  82  and a processor chip  72 . The user interface  82  includes an input/output port for transmitting and receiving data between the mobile surveillance point  50  and the subscriber computer  20 ,  22 ,  24 . In the preferred embodiment, the user interface  82  includes a disc drive capable of reading and writing to the data transfer device  40 ,  42 ,  44 . There are separate chips for processing and storing data; a processor chip  72  of the processor unit  70  stores and another chip executes image processing software  76 , text comparison software  78 , and image display software  80 . The preferred embodiment uses an Intel.RTM. Pentium 450 MHz processor with memory However, processors having at least 333 megahertz processor may be used. Although a preferred embodiment includes separate chips for processing and storing data, one skilled in the art would understand that these could be done in a single chip provided that such chip has sufficient processing and memory capacity. 
   The image processing software  76 , text comparison software  78 , and image display software  80  of the preferred embodiment are compatible with WindowsNT.RTM. operating platform, although compatibility with other operating platforms, such as Unix is also within the scope of the invention. The image processing software  76  contains instructions for capturing digital images from the camera  62 , and manipulating the images. The text comparison software  78  contains instructions for extracting and storing alphanumeric data from captured images, namely license plate numbers. The image display software  80  contains instructions for converting captured images to display images transmitted to the display unit  90 , further described below. These software programs  76 ,  78 ,  80  are stored in the processor chip  72  memory, or other memory device of the processor unit  70 . The image processing software  76  and the text comparison software  78  could be written in a variety of ways known to one skilled in the art of computer programming may build. The image display software  80  is known in the art and may be an off-the-shelf item. 
   The display unit  90  of the mobile surveillance point  50  is mounted by a bracket  96  in or on the police car  500 , preferably in a passenger compartment of the police car  500 . The display unit  90  has a display monitor  92 , an alarm  94 , and a control interface  99 . The control interface  99  operates with these controls keyboard for image selection, mechanism to reposition the camera, and an alarm (both audio and visual) to let the policeman know there is a match on a stolen vehicle. 
   When the system is in scan mode without a detection, the display is of vehicle tag number&#39;s currently being scanned, status of system, and images of vehicles in front of camera. The display monitor  92  shows image of vehicle and the list of information stored in stolen vehicle database when a match to a stolen vehicle is identified. The audio alarm frequency is to be determined. The visual alarm will have the screen change color to a red background and the system locking on the picture of the stolen vehicle. 
   The location of power unit  100  is application specific. Power is drawn from a power source  120 . With the mobile surveillance point  50 , the battery of the police car  500  serves as the power source  120 . A power converter and conditioner  102  regulate the mobile surveillance point  50  at 12 VDC. The power unit  100  has a power switch  106  and a power monitor  108  so that a police officer can turn the mobile surveillance point  50  on or off, and verify it has sufficient power throughout use. 
   Referring to  FIGS. 1 and 3 , the stationary surveillance point  52  is illustrated. The stationary surveillance point  52  is not a contained unit. The stationary surveillance point  52  has a camera unit  60 , a processor unit  70 , a power unit  100 , and a power source  120 . The camera unit  60 , processor unit  70 , and power unit  100  are substantially the same as those of the mobile surveillance point  50 . The camera, processor, and power units are the same in the mobile and stationary surveillance points. The image display software is excluded from the stationary unit. 
   The power source  120  for the stationary surveillance point  52  is vehicle power. The stationary surveillance point  52  can be positioned at any vantage point which where license plate images can be clearly captured by the camera  62 . 
   Operation is described in two parts. First, operation using the mobile surveillance point  50  is described. Second, operation using the stationary surveillance point  52  is described. 
   Referring to  FIGS. 1 and 2 , the operation of the mobile surveillance point  50  is illustrated. The central server  12  queries the NCIC database  2  via the communications link  3  updates the resident copy  14  prior to any downloads to subscribers. The updating program collects all stolen vehicle information for each particular jurisdiction and stores the updates of each regional theft database  26  in each user profile. At the beginning of a shift, the subscriber connects to the central server  12  via the secure communication link  5  and down loads the update of the regional theft database  26  to the subscriber computer  20 ,  22 ,  24 . 
   A copy of the regional theft database  26  is loaded onto the data transfer device  40 ,  42 ,  44 , for each patrol car  500 . An officer takes the data transfer device  40 ,  42 ,  44  and inserts it into the user interface  82  of the processor unit  70  of the mobile surveillance point  50 . Once inside the police car  500 , the officer turns on the mobile surveillance point  50  by pressing the power switch  106 . As the officer travels on patrol, the camera unit  60  continuously takes and processes images of vehicle license plates passing through the stream of traffic. Image data is transferred from the camera unit  60  to the processing unit  70 . The image processing software  76  separates plate number text from each image. The text comparison software  78  compares each plate number to the regional theft database  26  stored on the data transfer device  40 ,  42 ,  44 . If a match identifying a stolen vehicle is found, the event is logged with a date/time stamp with digital signal, the image is frozen on screen, all the data in record database is displayed, image is saved, there is an audio alarm, a visual alarm with background color changing to red, and a wait for reset. 
   Once a stolen vehicle is identified, the image display software  80  creates an overlay. The overlay includes one or more characterizing data fields of the vehicle, e.g., the make and/or model of the car, the Vehicle Identification Number, or VIN, color, license plate number, reporting agency, and date the vehicle was stolen. The image and overlay are shown on the display monitor  92  in the passenger compartment of the police car  500 . The officer then may use the image and text information to help identify the stolen vehicle while in pursuit. 
   Referring to  FIGS. 1 and 3 , the operation of the stationary surveillance point  52  is illustrated. 
   At least one, and preferably several, stationary surveillance points  52  are placed in various locations in a jurisdiction. Locations are initially selected by the individual law enforcement agencies that have an understanding of high-density crime areas in their jurisdictions. Locations are selected according to suspected avenues of travel where chop shops are likely to be located and where it is likely that stolen vehicles may travel. 
   A data transfer device  40 ,  42 ,  44  is inserted into the user interface  82  of the processor unit  70  of the stationary surveillance point  52 . The camera unit  60  captures images of all license plates traveling through the field of view. The stationary configuration simply records the license plate number for post-processing and images are dropped. 
   The surveillance data is stored to the data transfer device  40 ,  42 ,  44 . Once the surveillance data is stored for a period of time, for example and without limitation, 24 hours, the data transfer device  40 ,  42 ,  44  is removed, and replaced with another data transfer device  40 ,  42 ,  44 . The data transfer device  40 ,  42 ,  44  storing the surveillance data is taken to the subscriber computer  20 ,  22 ,  24 . The data transfer device  40 ,  42 ,  44  is inserted into the I/O device  21 ,  23 ,  25 . The spatial analysis software is run. The spatial analysis software is used to compare the surveillance data to the regional theft database  26 . Additionally, the spatial analysis software can be programmed to compare surveillance data collected by mobile surveillance points to the regional theft database  26 . Any matches identify a stolen vehicle. A regional map is shown on the monitor  27 ,  33 ,  39  of the subscriber computer  20 ,  22 ,  24 , showing the location of the stolen vehicle moving through the surveillance point. A log of the time the vehicle moved through each surveillance point and identifying data for that vehicle are displayed with the map. 
   A law enforcement officer observes the traffic pattern and determines if the patterns converge on a specific area or smaller location, indicating a chop shop may be in that area or location. If a trend develops, stationary surveillance points  52  can be moved to tighten a circle around the suspected chop shop location. Additionally, patrols can be increased in suspect areas. The surveillance process and trend analysis is repeated until an actual building location of a chop shop is likely or certain. Copies of the map displays and images of the stolen vehicles taken at the stationary surveillance points may be printed on the printer  150 ,  151 ,  152  of the subscriber workstation to be used as evidence in legal proceedings. 
   Although the system and method of the present invention is illustrated with data transfers occurring over a line-based communications link, it will be appreciated that some or all of the communications links may be wireless. In the wireless embodiment, wireless receivers and transponders may be added to, for example, the central server  12 , subscriber computer  20 ,  22 ,  24 , and mobile  50  and stationary  52  surveillance points to transmit and receive data. With the wireless embodiment, updates can occur more frequently. Further, this embodiment would not require a data transfer device  40 ,  42 ,  44  for transferring data. 
   Alternative embodiments of the present invention that have been contemplated include at least for the subscriber computer and server functions being combined at one computer so that a database can be loaded on the move. 
   Although the system and method of the present invention is illustrated in the context of surveillance of stolen vehicles, it will be appreciate that the system and method applies to surveillance of vehicles generally. This system and method can be used for other surveillance reasons, such as detecting the movement of terrorists or other types of thieves. For such applications, the stolen vehicle database  14  is replaced by another type of database, such as a felony vehicle database, and amber Alert database for abducted children, a recent “hot list” of vehicles involved in hit and run accidents or other crimes. 
   Although the preferred embodiment illustrates gathering stolen vehicle data from the NCIC database, it will be appreciated that the information may come from a variety of data and database sources. For example, one or more jurisdictional databases may be created and stored on the central server without departing from the scope of the present invention. In such alternatives, the logic for optimizing data from stolen vehicle databases  14  would simply be programmed to access the one or more jurisdictional databases may be created and stored on the central server. 
   The foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiment was chosen and described in order to explain the principles of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto, and their equivalents. The entirety of each of aforementioned documents is incorporated by reference herein.