Abstract:
According to the first aspect of the present invention, there is a data server ( 110 ) providing modified route information to a first user terminal ( 130 ) used by a first user, comprising a receiving unit ( 114 ) configured to receive a request from the first user terminal for requesting a second user terminal ( 120 ) used by a second user to modify route information, a geographical database ( 113 ) configured to store geographical data, a route information generation unit ( 112 ) configured to generate the route information indicating a route from a first location to a second location, using the geographical data, and a transmitting unit ( 115 ), configured to transmit a route modification request with the generated route information to the second user terminal. The receiving unit is further configured to receive modified route information from the second user terminal ( 120 ). The transmitting unit is further configured to transmit the modified route information to the first user terminal ( 130 ).

Description:
TECHNICAL FIELD 
     The present invention generally relates to a navigation system and method to receive an assigned another users&#39; feedback on the navigation terminal. The present invention particularly relates, but is not limited to, a system including a client mobile terminal for interaction with an IPTV system and a navigation system. 
     BACKGROUND ART 
     With advancements of mobile technology and positioning systems, user navigation using mobile devices has become a common practice. Currently, there are many mobile devices such as mobile phones, car navigation systems and the like, which have the ability to obtain the current geographical location using location evaluation technologies such as Global Positioning System (GPS) and signal strength based positioning systems. 
     Even though present navigation systems allow a mobile user to automatically obtain his/her (hereinafter male terms represents both genders) current position using technologies such as GPS, in general, navigation systems cannot automatically obtain users&#39; destination, which is necessary for providing navigation service. In most of the conventional cases the mobile user set the destination by himself at an initial stage of the navigation process. 
     However, there are cases where the user does not know the exact geographical location of the destination or/and the route (the path from current location to the destination location including both current location and destination location). Moreover, the route provided by the system might not be an optimal solution which satisfies mobile users&#39; need. 
     As an example, consider a case where a user is going to a friends&#39; birthday party organized at his friends&#39; house. A conventional navigation system may be providing the shortest route to his friends&#39; house. However, in case user wanted to buy a present on the way to the friends&#39; house, the user might want to choose a route that passes through a gift shop on the way to the destination (friends&#39; house). Such a situation can be considered as a case where the conventional navigation systems are unable to provide a suitable route. 
     When above mentioned situations are considered, one of the most realistic solutions available for the mobile user is asking the route from a person (an assigned user) who already knows the destination or the route. 
     Even though there are known art that discuss location data information sharing among paired navigation terminals (see Japanese Patent Application Laid Open: 2002-22482), in general, conventional navigation systems do not provide a mechanism that allow direct modification of the route displayed on a mobile terminal by an assigned another user. Thus, users has to depend on another communication channel, which is separated from the navigation system, such as a telephone call, to communicate with the designated user by voice and modify his route by himself according to the designated users&#39; instructions. However, this is not an effective or convenient method for a mobile user or a designated user. 
     SUMMARY 
     The present invention is intended to address the above-described problem, and it is a feature thereof to introduce a new technology that enables a navigation system where a user to be provided with a direct route information modification by an assigned another terminal user. 
     According to the first aspect of the present invention, there is a provided data server providing modified route information to a first user terminal used by a first user, comprising a receiving unit configured to receive a request from the first user terminal for requesting a second user terminal used by a second user to modify route information; a geographical database configured to store geographical data, a route information generation unit configured to generate the route information indicating a route from a first location to a second location, using the geographical data, and a transmitting unit, configured to transmit a route modification request with the generated route information to the second user terminal, wherein the receiving unit further configured to receive, modified route information from the second user terminal, the transmitting unit further configured to transmit the modified route information to the first user terminal. 
     According to the second aspect of the present invention, there is a provided user terminal which communicates with a data server and receives a request for modifying route information for a user of a first user terminal, comprising a receiving unit configured to receive the request including the route information from the data server, a display unit configured to display the route information, a user operation unit configured to accept user operations for modifying the route information, and a transmitting unit configured transmit the modified route information to the data server, wherein the modified route information indicating a route from a first location to a second location. 
     Further features of the present invention will become apparent from the following description of an exemplary embodiment with reference to the attached drawings, in which like reference characters designate the same or similar parts throughout the figures thereof. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1A  shows exemplary system architecture according to an embodiment of the present invention; 
         FIG. 1B  shows an exemplary functional block diagram of the Data Server; 
         FIG. 1C  shows an exemplary functional block diagram of the IPTV Terminal; 
         FIG. 1D  shows an exemplary functional block diagram of the Mobile Terminal; 
         FIG. 2  shows an exemplary sequence diagram representing the flow of processes and signaling when an assigned IPTV terminal user provides route information modification to a Mobile Terminal user in reply to the request made by the Mobile Terminal user according to an exemplary embodiment of the present invention; 
         FIG. 3  shows an exemplary data table that represents part of the related data saved on Presence Server  160  according to the present invention; 
         FIG. 4  shows an exemplary data table that represents part of the related data saved on Preference Server according to the present invention; 
         FIG. 5A  shows an exemplary view of the IPTV terminal display, displaying TV content streamed in normal situation; 
         FIG. 5B  shows an exemplary view of the IPTV terminal display, displaying an over laid modifiable route information over a IPTV stream; 
         FIG. 5C  shows an exemplary view of the IPTV terminal display, displaying a modifiable route information display by holding the IPTV stream; 
         FIG. 6A  shows an exemplary view of the IPTV terminal display, displaying a modifiable route information shown on a two-dimensional map view; and 
         FIG. 6B  shows an exemplary view of the IPTV terminal display, displaying a modifiable route information shown in a three-dimensional walkthrough view. 
     
    
    
     DETAILED DESCRIPTION 
     Networked terminals such as PC terminals, networked televisions and networked displays are ubiquitously available in our current living environment; and IPTV systems are gaining popularity among users as a fundamental method for receiving contents in such an environment. 
     In case the assigned user happened to be in front of a networked terminal with IPTV capability (hereinafter: IPTV terminal) such as a television connected to a set top box with IPTV capability or a PC with IPTV supported hardware and software installed, providing a mechanism to help the mobile user by directly modifying the route being provided to the mobile users&#39; terminal, using the IPTV terminal in hand, could enhance the mobile user experience dramatically and also could make providing instruction to the mobile user much easier for the IPTV terminal user (designated user). Especially, when IP Multimedia Subsystem (IMS) architecture is considered, there is a demand for a technology that allows such a mechanism. 
     Embodiments of the present invention that focus on the above mentioned user-need will now be described with reference to the attached drawings. The embodiment described below will be helpful in understanding a variety of concepts from the generic to the more specific. 
     It should be noted that the technical scope of the present invention is defined by claims, and is not limited by the embodiment described below. In addition, not all combinations of the features described in the embodiments are necessarily required for realizing the present invention. 
     The following embodiment is described in the context of IP Multimedia Subsystem (IMS), but the present invention is not limited thereto. It is possible to replace IMS infrastructure with web services infrastructure and achieve the same basic set of functionalities such as authentication, authorization, message routing, automated service lookup etc. It should be noted that if the present invention is applied for IMS, it is possible to provide modified route information to a mobile user by an assigned another user utilizing an IPTV terminal, which is advantageous over the conventional art. 
       FIG. 1A  shows a high-level system diagram according to an exemplary embodiment of the present invention. The main system elements are a Data Server  110 , an IPTV Terminal  120 , a Mobile Terminal  130 , a Content Server  140 , a Location Server  150 , a Presence Server  160 , a Preference Server  170 , and an IMS Gateway  180 . The Data Server  110  communicates with the IPTV Terminal  120  via the IMS Gateway  180 , the Mobile Terminal  130 , the Location Server  150 , the Presence Server  160 , and the Preference Server  170 . The IPTV Terminal  120  communicates with the Data Server  110  via the IMS Gateway  180  and the Content Server  140 . The Mobile Terminal  130  communicates with the Data Server  110  and the Location Server  150 . The Location Server  150  communicates with the Data Server  110  and the Mobile Terminal  130 . The Presence Server  160  communicates with the Data Server  110 ; the Preference Server  170  communicates with the Data Server  110 ; and the Content Server  140  communicates with the IPTV Terminal  120 . 
     The communication link may be a wireless connection such as the link between the Data Server  110  and the Mobile Terminal  130 , or may be a wired communication link such as the link between the IPTV Terminal  120  and the Content Server  140 . 
     The wireless link may accord to a radio communication protocol such as ANSI-136, GSM (Global Standard for Mobile) communication, GPRS (General Packet Radio Service), EDGE (Enhanced Data Rates for GSM Evolution), Code Division Multiple Access (CDMA), Wideband Code Division Multiple. Access (WCDMA), CDMA2000, Long Term Evolution (LTE) and UMTS (Universal Mobile Telecommunications System). The wired link may accord to Ethernet, FDDI(Fiber distributed data interface), Gigabit Ethernet, and etc. 
     The system element shown in  FIG. 1A  is considered to be directly IMS enable or able to access IMS services through a IMS Gateway  180  such as a HIGA (Home IMS Gateway) as disclosed in International Publication No. WO 2006/045706. In the present invention, the initial signaling such as service registration and authentication is conducted according to IMS standards. 
     As shown in  FIG. 1B  the Data Server  110  includes a Location Extraction Unit  111 , a Route Information Generation Unit  112 , a Geographical Database  113 , a Receiving Unit  114 , and a Transmitting Unit  115  as the main functional units. The Receiving Unit  114  receives information from each system element and Transmitting Unit  115  transmits information to each system elements, according to the requests by the Location Extraction Unit  111 , the Route Information Generation Unit  112 , and the Geographical Database  113 . The functional units are logically interconnected with each other, using a Data Bus  116  as shown in  FIG. 1B . In an IMS system, the Data Server  110  is implemented with an IMS Application Server as described in IMS specification (http://www.3gpp.org/ftp/Specs/archive/23_series/23.228/23228-860.zip). 
     The Location Extraction Unit  111  as shown in  FIG. 1B , extracts the current location of the Mobile Terminal  130  using a message received from the Mobile Terminal  130  or requesting the current location of the Mobile Terminal  130  from the Location Server  150 , which knows the current location of the Mobile Terminal  130 . 
     The Geographical Database  113  as shown in  FIG. 1B , contains two types of geographical information; still image type geographical information that used for two-dimensional map view and motion image type geographical information that used for three-dimensional walk-through view. The detail level of each geographical information type contained in the Geographical Database  113  can be selected. The data structure used in the Geographical Database  113  supports such selection. 
     The Route Information Generation Unit  112  as shown in  FIG. 1B , generates route information that includes a route from a current location to a destination, geographical details of surrounding area and user view preference information that describes presentation method. Here, the created route information type may be the still image type or the motion image type according to users&#39; preference. Moreover, the route is represented as a set of location coordinates according to some coordinate system such as WGS 84 including, the current location, the destination location and the points which represent the route between the current location and the destination location. As an example, in case a user wishing to use a navigation service is using a mobile phone, the user might prefer to receive the route information as a two-dimensional map view; on the other hand, when the user is in front of an IPTV terminal  120 , the user might prefer to receive the route information as a three dimensional walkthrough view. Here, the Data Server  110  receives preference of the user from the Preference Server  170  and the route information created by Route Information Generation Unit  112  according to these users&#39; preference. 
     As shown in  FIG. 1C  the IPTV Terminal  120  includes a Display Unit  121 , an Operation Unit  122 , a Content Receiving Unit  123 , a Receiving Unit  124 , and a Transmitting Unit  125  as the main functional units. The Receiving Unit  124  receives information from each system element and the Transmitting Unit  125  transmits information to each system element, according to the requests of the Display Unit  121 , the Operation Unit  122 , and the Content Receiving Unit  123 . The functional units are logically interconnected with each other, using a Data Bus  126  as shown in  FIG. 1C . 
     The Display Unit  121  processes the information to be shown on the display and then displays the information on a monitor.  FIGS. 5A to 5C  and  FIGS. 6A and 6B  show examples of the Display Unit  121  output on the monitor. The  FIG. 5A  shows a case where an IPTV stream is displayed on full screen  510  and a incoming route correction request is indicated by an icon  512 ;  FIG. 5B  shows a case where a two dimensional map data (geographical information) is overlaid on the IPTV stream; and  FIG. 5C  shows a case where a two dimensional map data (geographical information) is displayed on full screen by holding the IPTV stream. The  FIG. 6A  shows a case where modifiable map is shown on a two dimensional map view  610 . In  FIG. 6A , a route  613  from the current location  611  to the destination location  612  is displayed.  FIG. 6B  shows a case where modifiable map is shown in a walkthrough view  620 . The route  621  shows a traveling direction towards the destination location. 
     The Operation Unit  122  accepts user operations conducted by the user using devices such as a remote controller, keyboard, touch-screen and etc. The Operation Unit  122  also generates corresponding visual feedback based on user operations through the Display Unit  121 . 
     The Content Receiving Unit  123  receives streaming contents generated at the Content Server  140  through the Receiving Unit  124 . The received contents are passed into the Display Unit  121  after conducting basic processing such as data flow control. Then, the Display Unit  121  displays the streaming data received from the Content Receiving Unit  123  accordingly. 
     The Mobile Terminal  130  as shown in  FIG. 1D  includes a Display Unit  131 , an Operation Unit  132 , a Receiving Unit  134  and a Transmitting Unit  135  as main functional units. 
     The Receiving Unit  134  receives data and the Transmitting Unit  135  transmits the data according to the instructions provided by the central processing unit (CPU) of the Mobile Terminal  130 . The Display Unit  131  displays information to be displayed to the mobile user; the Operation Unit  132  comprise of operating units such as buttons, touch screens and etc, and is used for receiving the user input. The Mobile Terminal  130  user may trigger a request for route modification using the Operation Unit  132 . 
     The Content Server  140 , as shown in  FIG. 1A , generates IPTV contents sent to the IPTV terminal  120 . The Content Server  140  has a bidirectional communication channel with the IPTV terminal  120  and it can hold the content stream and restart when needed according to the IPTV terminals&#39;  120  request. 
     The Location Server  150 , as shown in  FIG. 1A , receives the current location of the Mobile Terminal  130  which obtains the current location by internal sensors such as GPS receivers installed into the Mobile Terminal  130 . The Location Server  150  may utilize external sensing methods such as signal strength based location sensing methods and etc. The Location Server  150  records the current locations of a plurality of Mobile Terminals  130  in a location database. The Location Server  150  identifies each Mobile Terminal  130  by its Mobile Terminal ID and uses it to manage current location of each Mobile Terminal  130  in the location database. The Mobile Terminal ID may be an identifier such as MAC address, IMPI (IP Multimedia Private Identity), and etc. which allows identifying the terminal uniquely. The Location Server  150  is always able to know the current location of the Mobile Terminal  130  using an appropriate location sensing method. The Location Server  150  is implemented as a location server according to the IMS specifications. 
     The Presence Server  160  knows the presence of each user and sends the presence information of a user in response to a request from the Data Server  110 . A part of an exemplary presence data table managed by the Presence Server  160  is shown in  FIG. 3 . Each row of the data table represents a value of the following tuple: &lt;User ID  301 , Destination  302 , Terminal Type  303 , User Status  304 &gt;. Here, the User ID  301  represents an identifier of the user to be used to uniquely identify the user. The Destination  302  contains a network address of a device allowed to be used by a user with the User ID  301 . The Terminal Type  303  contains information about terminal functionality (TV, PC, etc.). The User Status  304  contains users&#39; status at each terminal in that moment (online, offline, idle, etc.). 
     When the Data server  110  requests presence information of a user, the data server  110  can send a request of the presence information with the User ID to the Presence Server  160 . The Presence Server  160  can provide presence information corresponding to the received User ID in a plurality of methods. As an example, the Presence Server  160  access all the tuple entries with the same User ID and among them selects the tuple with User Status  303  set to “online” and then, sends information of the selected tuple to the Data Server  110 . The above discussed functionality of the Presence Server  160  is implemented according to the presence server specifications (http://www.3gpp.org/ftp/Specs/html-info/24141.htm) of an IMS system. 
     The Preference Server  170  contains general preference information, including route display preference of a plurality of present system users. The Preference Server  170  sends preference information of a user in response to a request from the Data Server  110 . To explain the functionality of the Preference Server  170 , part of an exemplary Preference data table managed by the Preference Server  170  is shown in  FIG. 4 . Each row of the data table represents a value of the following tuple: &lt;User ID  401 , TV Program Priority  402 , Terminal Type  403 , Route Data Type  404 , Type of View  405 &gt;. The user ID  401  represents the identifier of a user. The TV Program Priority  402  represents the priority level of each TV program set according to initial information provided by the user. The Terminal Type  403  represents functionality of each terminal (TV, PC etc.). The Route Data Type  404  represents preferred data presentation of the route (still image or motion image). The Type of View  405  indicates the preferred displaying method of geographical information on a monitor. 
     When the Data server  110  requests preference information of a user, the Data server  110  can send a request of the preference information with the User ID to the Preference Server  170 . The Preference Server  170  can provide-preference information corresponding to the received User ID in a plurality of methods. As an example, if the Data Server  110  only has the user ID then all the preference values corresponding to the provided User ID  401 , the values of the TV Program Priority  402 , the Terminal Type  403 , the Route Data Type  404  and the Type of View  405  in the table  400 , may be sent to the Data Server  110 . On the other hand if the Data Server  110  has the corresponding value of the TV Program Priority  402  and the corresponding value of the Terminal Type  403  as well as the user ID  401 , then the Preference Server  170  is able to send exact user preferred Route Data Type  304  value and the Type of View  305  value. The preference information request from the Data Server  110  includes at least users ID  401  with the request, and the corresponding reply is formed according to available information for each user as denoted in the above examples. The above functionality of the Preference Server  170  is implemented in a XDMS (the profile management system) server in an IMS system (http://member.openmobilealliance.org/ftp/Public_docume nts/PAG/Permanent_documents/OMA-AD-XDM-V2 — 1-20081022-D.zip). 
     Above, the characteristics of each element of the present embodiment is explained. Hereupon, the procedure and signal flow of the system when a user requests for a route modification is discussed. The discussion is conducted in correspondent to sequence diagram of  FIG. 2 . An exemplary case is considered were a Mobile Terminal  130  user (mobile user) requests a route modification from an assigned user (IPTV user), who is watching an IPTV stream on an IPTV Terminal  120 . In this case, the users have registered with the Presence Server  160  and system knows their presence in each terminal according to the IMS standards. Moreover, the initial authentication and the signaling are conducted according to IMS standards. 
     In step S 1 , The Mobile Terminal  130  sends a request for route modification to the Data Server  110 . This request includes the user ID of the designated user (IPTV users&#39; ID in this case) and the destination location. 
     In step S 2 , the Data Server  110  requests current location of the Mobile Terminal  130  from the Location Server  150 . This request includes the Mobile Terminal ID. The Mobile Terminal ID is an identifier that allows uniquely identifying the Mobile Terminal  130 , for example IMPI (IMS Private User Identity), which may be used by the Location Server  150  to manage the location database. 
     In step S 3 , the Data Server  110  receives current location data of the Mobile Terminal  130  from the Location Server  150 . The current location data includes present location coordinates of the Mobile Terminal  130 . However, in case the current location data of the Mobile Terminal  130  is included in the route modification request received in step S 1 , the steps S 2  and S 3  may be skipped. 
     In step S 4 , the Data Server  110  requests the presence information of the user from the Presence Server  160 . The request includes at least a user ID of the designated user. 
     In step S 5 , the Data Server  110  receives the presence information of the user from the Presence Server  160 . The presence information includes a network address indicating Destination  402  and a value indicating Terminal Type  403  regarding the current terminal in use by the designated user. Based on the destination information included in the presence information, the Data Server  110  obtains the network address of the IPTV terminal  120  (the current terminal in use by the designated user). 
     In step S 6 , the Data Server  110  requests preference information of the designated user from the Preference Server  170 . The request at least includes a user ID of the designated user. 
     In step S 7 , the Data Server  110  receives the preference information of the designated user from the Presence Server  160 . The preference information includes display preference and route data type preference. As shown in  FIG. 4 , the Preference Server  170  includes information on the TV Program Priority  402 , the Terminal Type  403 , the Route Data Type  404  and the Type of View  405 . As an example, considering User ID=1244 is the designated user, in case TV Program Priority is “1” and the terminal in use is a “TV”, the Route Data Type  404  preference is “still image” and Type of View  405  preference is “hold” according to the data table  400 . On the other hand, in case TV Program Priority is “3” and the terminal in use is a “PC”, the Route Data Type  404  preference is “still image” and the Type of View  405  preference is “overlay” according to the data table  400 . Based on this response, the Data Server  110  selects a suitable method to present the route data on the display depending on users&#39; preferences. 
     In step S 8 , the Data Server  110  generates the route information and adapts the information according to the IPTV terminal  120  preference obtained from the Preference Server  170  in step S 7 . In case the mobile user did not include the destination location in his route modification request, the Data server  110  set designated users&#39; location as the destination. The location address of the designated user may be obtained from the Presence Server  160 . The Presence Server  160  can manage the geographical location address of each device registered in the table  300 . The route modification request created for sending from Data Server  110  to IPTV Terminal  120  contains at least the current location, the destination location, surrounding geographical data according to designated users&#39; preference. The route modification request may include description control IPTV stream according to the received display preference (a value in Type of View  405  of  FIG. 5 ). 
     In step S 9 , Data Server  110  sends the created route modification request to the IPTV terminal  120  using the Destination  302  of the IPTV terminal  120  obtained in step S 5 . 
     In step S 10 , the IPTV terminal  120  conducts control signaling with the Content Server  140  and controls IPTV stream according to the received display preference (a value in Type of View  405  column of  FIG. 5 ). 
     In step S 11 , in case the type of view  405  received from the Data Server  110  is “overlay”, the IPTV Terminal  120  continues displaying the IPTV stream, while overlaying the route information on the IPTV stream as shown in  FIG. 5B . In case the showing preference is “hold” the IPTV stream is held and route information is shown in the display as shown in  FIG. 5C . 
     In step S 12 , the assigned user modifies the route using the Operation Unit  122 . The IPTV terminal  120  accepts the modifications conducted by the assigned user. In case of the two-dimensional map view, first the modification conducted to the route  613  by the assigned user is accepted by the Operation Unit  122 , and then based on the accepted modified route information the points which represents the route is updated. In case of the three-dimensional walkthrough view, first the modification conducted to route  621  by assigned user by changing the advancing direction and/or turning points is accepted and recoded by the Operation Unit  122 , and then based on the accepted modified route information the points which represents the route is updated. 
     In step S 13 , after the route modification of step S 12  is concluded, the IPTV stream is controlled accordingly to restore the previous IPTV stream, by conducting signaling between the IPTV terminal  120  and the Content Server  140 . 
     In step S 14 , IPTV terminal  120  sends the modified route information to the Data Server  110 . The modified route information contains at last the current location of the mobile user, the destination location and set of location coordinates that defines the modified route from current location to the destination location. 
     In step S 15 , similarly to the step S 4 , the Data Server  110  request for presence information of the mobile user from the Presence Server  160 . The presence information such as busy, invisible and etc. that obtained in this step can be utilized for defining preference rules. As an example when user is busy selecting one set of preferences or changing the usual preference settings can be given. However, in case such rule based preference selection is not conducted S 15  may be skipped. 
     In step S 16 , similarly to the step S 5 , the Data Server  110  receives presence information of the mobile user from the Presence Server  160 . 
     In step S 17 , similarly to the step S 6 , the Data Server  110  request for preference information of the mobile user from the Preference Server  170 . 
     In step S 18 , similarly to the step S 7 , the Data Server  110  receives preference information of the mobile user from the Preference Server  170 . 
     In step S 19 , similarly to the step S 8 , the Data Server generates modified route information based on modified route information received from the IPTV terminal  120  and adapts the information to Mobile Terminal  130  according to mobile users preferences. 
     In step S 20 , The modified route information adapted to the Mobile Terminal  130  is sent to the Mobile Terminal  130  from the Data Server  110 . 
     In step S 21 , The Mobile Terminal  130  displays the modified route information. 
     In another embodiment according to the present invention, the mobile user may choose to navigate from an arbitrary location other than the current location of the Mobile Terminal  130  as a start point of the navigation. The mobile user may specify that location as the navigation starting point on the map displayed on the display unit  131  of the Mobile Terminal  130  using the operation unit  132 . The mobile user may include the specified location in the route modification request of S 1  in  FIG. 2 . In this case, the specified location is used instead of the current location of the Mobile Terminal  130  in following steps, and allows obtaining the modified route information from the specified location to the destination. The Location Extraction Unit  111  extracts the specified location from the message received from the Mobile Terminal  130 . If necessary, the Location Extraction Unit  111  may obtain a location coordinates corresponding to the specified location from the Location Server  150 . 
     While the present invention has been described with reference to the exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.