Patent Description:
<CIT> discloses generating a query index and querying on the basis of the query index in road-network management.

<CIT> discloses method of detecting the closure and/or opening of a navigable element forming part of a network of navigable elements within a geographic area.

Therefore, there is a need for automatically resolving potential inconsistencies between road closure states before, e.g., publishing road closure reports to end users.

In various example embodiments, the methods (or processes) can be accomplished on the service provider side or on the mobile device side or in any shared way between service provider and mobile device with actions being performed on both sides.

Still other aspects, features, and advantages of the invention are readily apparent from the following detailed description, simply by illustrating a number of particular embodiments and implementations, including the best mode contemplated for carrying out the invention. The invention is also capable of other and different embodiments, and its several details can be modified in various obvious respects, all without departing from the spirit and scope of the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

Examples of a method, apparatus, and computer program for providing road closure graph inconsistency resolution are disclosed. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. It is apparent, however, to one skilled in the art that the embodiments of the invention may be practiced without these specific details or with an equivalent arrangement. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring the embodiments of the invention.

<FIG> is a diagram of a system <NUM> capable of automatically resolving road closure inconsistencies, according to one embodiment. As noted above, information on road closures occurring in a road network can be important for providing services such as trip planning, navigation routing or guidance, estimating time of arrival, and/or the like. Generally, traffic incidents such as road closures (e.g., road closure reports <NUM>) are published by government/municipality agencies, local police, and/or third-party official/semi-official sources (e.g., a services platform <NUM>, one or more services 105a-105n, one or more content providers 107a-<NUM>, etc.). By way of example, the published road closure reports <NUM> can specify the roadway (e.g., by name or matched to specific road link records of digital map data such as a geographic database <NUM>) that has been closed or partially closed to traffic (e.g., vehicular and/or non-vehicular traffic). Closure refers, for instance, to restricting traffic flow on a particular roadway such that no vehicle or a reduced number of vehicle (e.g., reduced with respect to an average free flow traffic volume on the roadway) is permitted or able to travel on the roadway.

In one embodiment, a traffic provider (e.g., via a mapping platform <NUM>) monitors the feeds of the road closures reports <NUM>, extracts the affected roadways (e.g., road segments or links), and provides traffic data and/or other functions based on the road closure reports <NUM> (e.g., displays the location of reported closures on the map, generates navigation routes to avoid reported road closures, etc.). Then, traditional traffic service providers wait for another message or road closure report <NUM> indicating that the road has opened to provide updated data and/or functions. In one embodiment, this type of incident reporting is referred to as "journalistic reporting.

In one embodiment, journalistic incident reports can be coupled with other information (e.g., GPS probe information collected from vehicles 113a-<NUM>, also collectively referred to as vehicles <NUM>) and verified automatically. This process involves monitoring (e.g., by the mapping platform <NUM>) the reported road segment for the duration of the report and determining the closure state (e.g., whether the road segment is closed or open) periodically or based on events as they occur (e.g., vehicle activity). This is called, for instance, an "automatic road closure verification" methodology.

Furthermore, independent of journalistic reports, the system <NUM> (e.g., via the mapping platform <NUM>) can monitor a set of roadways and detect road closures in the absence of journalistic reports based, for instance, on vehicle probe data, road sensors, or equivalent. This methodology is referred to as "automatic road closure detection. " In one embodiment, the automatic closure verification and detection mechanisms of the mapping platform <NUM> can calculate a closure likelihood score for a road segment and based on this score. Based on the road closure score, the mapping platform <NUM> can classify the closure states of monitor road segments to close roads that are open, to open roads that are closed, and/or to take no action.

Regardless of the mechanism used to determine road closures (e.g., journalistic reports, automatic verification and detection, etc.), there is a potential risk of creating inconsistent road closure reports. For instance, a construction report could result in the system <NUM> classifying a road A on which the construction is occurring as closed to vehicular traffic. If there exists another road, road B, whose traffic can only flow from road B to road A, technically B is also closed even though it does not have construction on it. This is because vehicles entering road B would have nowhere to go because road A is closed. Therefore, service provider face significant technical challenges to resolving this inconsistency so that vehicles <NUM> entering road B can be provided with road closure data to know that they cannot continue their journey.

Automatic closure verification and detection methods can suffer from similar inconsistencies. In one embodiment, these methods calculate a closure likelihood for road segments. Continuing with the road structure of the example above, it can be the case where the calculated closure probability or score for road A is above the closure threshold, whereas the closure probability or score for road B is below the closure threshold. In that case, road A is marked closed, and road B is marked open. However, due to the road network, if A is closed, so should B; and conversely, if A is open, so should B. These inconsistencies can result in the system <NUM> devoting excess and unnecessary storage and/or computing resources to maintain incorrect or poor quality road closure data.

To address these problems, the system <NUM> introduces a technical solution which adds context to determined road closures (e.g., road closures determined from journalistic reports, automatic closure detection/verification, and/or equivalent processes) using the road network structure (e.g., determined from map data of the geographic database <NUM> or equivalent) around a road closure and by doing so removes inconsistencies in road closures. In other words, the system <NUM> evaluates an entire road network or structure around a road closure and resolves any closure inconsistencies. Inconsistencies occur if one road segment cannot be closed while another road segment is open or vice versa.

In one embodiment, the system <NUM> determines that a road closure has been either reported journalistically or automatically. In case of journalistic reports, the reported road closure goes through automatic road closure verification system where the system builds a connected roadway network around the closure, referred as roadway graph (e.g., a mathematical graph representing the structure of spatial relationships of road segments or link in the graph) henceforth. The verification, for instance, evaluates vehicle probe data (e.g., vehicle GPS location traces or trajectory data) collected from road segments in the reported closure. The result is a closure likelihood score associated with each road segment and a closure state (closed or open). This score-based closure state can then be used to verify the journalistic report of the road closure.

In the case of automatically detected road closures (as opposed to journalistic reports), again a closure likelihood is calculated per road segment using collected vehicle probe data (e.g., collected from one or more sensors 115a-<NUM>, also collectively referred to as sensors <NUM>, of the vehicles <NUM>). In addition or alternatively, the system <NUM> can monitor certain select road segments (e.g. those with high closure likelihood) to automatically detect road closures and then confirm the road closures through an automatic verification system according to the embodiments described above.

Whichever path is followed (e.g., journalistic reports or automatic detection of road closures), a roadway graph which comprises a set of road segments with closure likelihood score and potentially another set of roadways without any score can be created. In one embodiment, the roadway graph can be created as part of the processed used to automatically verify and/or detect the road closures; or can be generated in a separated process after road closure detection and verification. In one embodiment, the system <NUM> processes the roadway graph and the road structure/spatial relationships represented therein to detect inconsistencies in roadway closure states among road segments or links in the graph and resolves them by change the closure states to make them consistent (e.g., by opening or closing roadways in the roadway graph).

Resolution of inconsistencies in road closure data (e.g., stored in the closure data layer <NUM> of the geographic database <NUM>) using the road network structure or topology around road closures provides several technical advantages. These advantages include but are not limited:.

In one embodiment, as shown in <FIG>, the mapping platform <NUM> of the system <NUM> includes one or more components for providing road closure graph inconsistency resolution according to the various embodiments described herein. It is contemplated that the functions of these components may be combined or performed by other components of equivalent functionality. As shown, in one embodiment, the mapping platform <NUM> includes a closure module <NUM>, a roadway graph module <NUM>, an inconsistency module <NUM>, and a resolution module <NUM>. The above presented modules and components of the mapping platform <NUM> can be implemented in hardware, firmware, software, or a combination thereof. Though depicted as a separate entity in <FIG>, it is contemplated that the mapping platform <NUM> may be implemented as a module of any of the components of the system <NUM> (e.g., a component of the vehicle <NUM>, services platform <NUM>, services 105a-105n (also collectively referred to as services <NUM>), etc.). In another embodiment, one or more of the modules <NUM>-<NUM> may be implemented as a cloud-based service, local service, native application, or combination thereof. The functions of the mapping platform <NUM> and modules <NUM>-<NUM> are discussed with respect to <FIG> below.

<FIG> is a flowchart of a process for automatically resolving road closure inconsistencies, according to one embodiment. In various embodiments, the mapping platform <NUM> and/or any of the modules <NUM>-<NUM> may perform one or more portions of the process <NUM> and may be implemented in, for instance, a chip set including a processor and a memory as shown in <FIG>. As such, the mapping platform <NUM> and/or any of the modules <NUM>-<NUM> can provide means for accomplishing various parts of the process <NUM>, as well as means for accomplishing embodiments of other processes described herein in conjunction with other components of the system <NUM>. Although the process <NUM> is illustrated and described as a sequence of steps, it is contemplated that various embodiments of the process <NUM> may be performed in any order or combination and need not include all of the illustrated steps.

In one embodiment, the process <NUM> assumes that a road closure has been reported journalistically or automatically, and/or determined using any equivalent means. The road closure can be stored as one or more road closure reports <NUM>. It is contemplated that the road closure report <NUM> can be generated and/or transmitted in any data format and includes data indicating a location or roadway affected by a road closure. The data can include a direct indication of the affected link (e.g., by specifying the link IDs corresponding to the roadway or segments affected by the reported road closure), or an indirect indication (e.g., address or offset location that can then be map-matched or translated to corresponding links of the geographic database <NUM>). In some embodiments, the road closure report <NUM> can optionally include other contextual data such as type of closure, duration of closure, timestamp information, and/or the like. For journalistic reports, the closure module <NUM> monitor reports received from one or more entities (e.g., government/municipality agencies, police agency, and/or any other third party source of road closure data). For automatic verification and/or detection, the closure module <NUM> can perform or initiate monitoring of vehicle probe data from road segments of interest to classify or score a likelihood of a closure occurring on the road segments (e.g., based on probe volume, speed, location, heading, etc. meeting thresholds for classifying road segment as open or closed).

In step <NUM>, if a roadway graph has not been generated as part of the road closure verification or detection process, the roadway graph module <NUM> process map data (e.g., stored in the geographic database <NUM>) to generate a roadway graph representing a spatial relationship between road segments affected by the reported road closure or within a proximity threshold of the reported road closure (e.g., spatial relationship between a first road segment with a reported road closure and then a second road segment flowing into or from the first road segment). In other words, the roadway graph module <NUM> a roadway graph or closure link graph comprising a connected set of road segments or links including the road links indicated in the road closure report <NUM> being evaluated. In one embodiment, a road link or segment is the unit representation of a roadway in a digital map such as the geographic database <NUM>. Additional description of a link data record is described below with respect to <FIG> below. Generally, a roadway between two consecutive intersections can be represented by one or more links. However, a single link does not span more than the distance between two intersections.

In one embodiment, the closure link graph is used to seal or designate the reported closure area and monitor traffic around and through the closure within the area represented by the closure link graph. As described above, a closure incident is reported on a stretch of roadway (e.g.. , via a road closure report <NUM>). This closure report <NUM> is then converted into a set of links. As shown in <FIG>, these links (e.g., links 401a-401f, also collectively referred to as links <NUM>) can be and unordered set <NUM> (e.g., unordered with respect to a spatial arrangement).

If the links <NUM> are unordered, the roadway graph module <NUM> initiates the building of the closure link graph around these links <NUM> by ordering the links <NUM> so that the end of one link is arranged to match the beginning of the next closest link based on the respective locations of their beginning and end nodes. The ordered set <NUM> of the links <NUM> is also illustrated in <FIG>. The ordered set <NUM> of the links <NUM> corresponds to the abstract representation of the physical structure road segments making up the roadway indicated in the processed road closure report <NUM>.

Next, the roadway graph module <NUM> adds links upstream to and downstream from the reported closures to construct the closure link graph <NUM>. Since these links (e.g., links 409a-409o, also collectively referred to as links <NUM>) are not among the original links <NUM> identified in the processed road closure report <NUM>, the links <NUM> are assumed to be open and not closed to traffic. The resulting the closure link graph <NUM> then includes the reportedly closed links <NUM> buffered by links <NUM> that are open for travel. In other words, with the addition of open upstream and downstream links <NUM>, the closure (e.g., on links <NUM>) is now isolated. For example, given the closure links <NUM>, all traffic going into and out of the closure region can be monitored using the traffic flowing in the open links <NUM>.

In one embodiment, the flow of traffic is determined by collecting probe data from vehicles. For example, the roadway graph module <NUM> retrieves probe data collected from vehicles traveling on the roadways corresponding to the closure link graph <NUM>. In one embodiment, probe data includes raw GPS probes (e.g., probe points) sent from vehicles indicating their respective locations by, for instance, a latitude and longitude pair. Then, each probe point is placed onto a most probable link on the map using a map matching process. On example map-matching process works as described in the following section. A map is defined by a set of links and their geographic coordinates. Because GPS (or other similar location positioning technology) is not <NUM>% accurate, the coordinates of a vehicle GPS probe most of the time do not fall onto a link perfectly. To account for this error, map matching algorithms take the coordinate of a GPS probe, and find the neighboring links whose coordinates are close to the probe. Then, the map matching process places the vehicle probe onto the most probable link based on pre-defined criteria of the specific map matching process or algorithm being used.

In one embodiment, to better control for map matching error, the roadway graph module <NUM> described herein works with vehicle paths instead of map matched vehicle probes. The reason is that map matched vehicle probes can be more are susceptible to map matching errors than vehicle paths. By way of example, a vehicle path or trajectory is derived from two consecutive map matched vehicle probes. The path can then be increased by adding new probe points on top of the previously calculated vehicle path as new probe points are collected.

In one embodiment, the roadway graph module <NUM> can process the probe data to calculate vehicle paths traversing the monitored closure link graph <NUM> according to the example process described below. Firstly, for a specific vehicle, the roadway graph module <NUM> takes the first and second probe points received, e.g., denoted as probe1 and probe2. If the time difference between these probes is more than a specified threshold, the roadway graph module <NUM> discards the initial probe1, and the sets probe1 = probe2. The roadway graph module <NUM> then retrieves the next probe point to set as probe <NUM> to iteratively evaluate the time difference.

If the time difference is less than the specified threshold, the roadway graph module <NUM> builds a vehicle path from probe1 to probe2. It is contemplated that the roadway graph module <NUM> can use any path building process or algorithm such as but not limited to A* pathfinding or equivalent. The roadway graph module <NUM> then records the new path for the vehicle, discards probe1, sets probe1 = probe2, and retrieves the next probe point to act as probe2 until all probe points collected for the specific vehicle have been processed.

In one embodiment, every vehicle can send its probe points (e.g., GPS probes) at a different frequency; this frequency can vary from <NUM> second to a few minutes. Therefore, as a vehicle drives through multiple links, there is no guarantee that it will send a probe from every link. For instance, if a vehicle drives at fast speeds over short links while sending a probe every <NUM> minutes, it would almost be certain that its two consecutive probes will arrive from non-neighboring links. This sporadic or sparse probe reporting can make it more technically challenging to build accurate vehicle paths.

To address this technical challenge, in one embodiment, as part of its link graph building process, the roadway graph module <NUM> can aggregate links and their probes where it makes sense into superlinks. In one embodiment, a superlink consists of ordered links such that if a vehicle travels through one of its links, it is guaranteed to travel through the other links of the same superlink as well. An example of a superlink is a section of a highway stretching between two entrance / exit ramps. When on this stretch a vehicle must go through all the links part when driving this stretch. Another example is a roadway between two intersections in a city road. Because a superlink comprises one or more links, superlinks are often longer than normal links of the geographic database <NUM>, thereby increasing the probability that a probe point of a vehicle path would fall on the superlink than on a normal link. In addition, the superlinks can decrease the overall complexity of the closure link graph <NUM> without affecting the quality of the closure evaluation results, thereby reducing computing resources (e.g., processing resources, memory resources, bandwidth resources, etc.) associated with automatic evaluation of road closure reports according to the various embodiments described herein.

<FIG> is diagram of an example of aggregating road links of the closure link graph <NUM> into superlinks, according to one embodiment. <FIG> continues the example closure link graph <NUM> of <FIG> and illustrates a first superlink graph <NUM> that is a version of the closure link graph <NUM> in which the reportedly closed links <NUM> are aggregated into respective superlinks. In this example, links 401a and 401b can form a superlink 503a because a vehicle on link 401a must also travel through link 401b. Similarly, links 401c and 401d can be aggregated as superlink 503b, and links 401e and 401f can be aggregated into superlink 503c.

In one embodiment, the upstream and downstream links <NUM> can be aggregated into superlinks in addition to the links <NUM> to construct superlink graph <NUM>. For example, links 409a and 409b can be aggregated into superlink 507a, links 409c-409e can be aggregated into superlink 507b, links 409f and <NUM> can be aggregated into superlink 507c, links <NUM> and 409i can be aggregated into superlink 507d, links 409j-<NUM> can be aggregated into superlink 507e, and links <NUM> and 409o can be aggregated into superlink <NUM>. Referring for instance to the example of <FIG> and <FIG>, if a vehicle has probe points on link 401a, 401c, and 401f, the roadway graph module <NUM> can calculate the vehicle path to include links all links 401a-401f based on the superlinks 503a-503c. In one embodiment, links and superlinks can be used interchangeably in the various embodiments described herein. Therefore, where links are described without reference superlinks, it is contemplated that superlinks can be used in addition to or as alternate to links, and vice versa.

Returning to step <NUM> of the process <NUM> of <FIG>, the inconsistency module <NUM> can determine inconsistencies in road closure data associated with the roadway graph (e.g., as constructed above in step <NUM>). In one embodiment, a road closure inconsistency means that in a connected roadway graph, two or more links (e.g., representing a first road segment and a second road segment) cannot co-exist with the given closure status or state. In other words, the roadway indicates a spatial relationship between at least two road segments where that a first closure state of the first road segment cannot differ from a second closure state of the second road segment (i.e., road segment A cannot have "open" state while roadway B is in "closed" state, or vice versa).

Several road closure inconsistencies can arise in a connected roadway graph depending on the underlying structure or spatial relationship of the road segments in the graph. Examples of these inconsistencies are discussed with respect to a road structure <NUM> (also referred to as Structure <NUM>) of <FIG> and a road structure <NUM> (also referred to as Structure <NUM>) of <FIG>. In the example of <FIG>, Structure <NUM> (e.g., road structure <NUM>) of the roadway graph illustrates a structure in which a set of superlinks flow into only one superlink (e.g., Link X). Accordingly, assuming that Link X is the first road segment of interest, there would be one or more second road segments that are incoming road segments that flow into the first road segment. In the example of <FIG>, Structure <NUM> (e.g., road structure <NUM>) of the roadway graph illustrates a structure in which a set of superlinks have only one source superlink (e.g., Link X) flowing into them. Accordingly in this example, assuming that Link X is the first road segment of interest, there would be one or more second road segments that are outgoing road segments that flow from the first road segment.

In one embodiment, given the Structure <NUM> and Structure <NUM>, the following closure state inconsistencies can arise in roadway or closure graphs containing one or more of the structures:.

In one embodiment, to detect one or more of the inconsistencies described above in a roadway graph of interest, the inconsistency module <NUM> searches the graph for road topologies that match Structure <NUM> and/or Structure <NUM>. The inconsistency module <NUM> can then determine the closure states of the road segments comprising the detected structures to identify one or more of the inconsistencies described above. For example, to detect Inconsistency <NUM>, the inconsistency module <NUM> processes the roadway graph to determine that: (<NUM>) the roadway graph indicates that the second road segment is an incoming road segment that flows into the first road segment; (<NUM>) the road closure state of the first road segment is closed; and (<NUM>) the road closure state of the second road segment is open. To detect Inconsistency <NUM>, the inconsistency module <NUM> processes the roadway graph to determine that: (<NUM>) the roadway graph indicates that the second road segment is an incoming road segment that flows into the first road segment; (<NUM>) the road closure state of the first road segment is open; (<NUM>) the road closure state of the second road segment is closed, and (<NUM>) all other incoming road segments (if any) flowing into the first road segment are closed. To detect Inconsistency <NUM>, the inconsistency module <NUM> processes the roadway graph to determine that: (<NUM>) the roadway graph indicates that the second road segment is an outgoing road segment that flows from the first road segment; (<NUM>) the road closure state of the first road segment is closed; and (<NUM>) the road closure state of the second road segment is open. To detect Inconsistency <NUM>, the inconsistency module <NUM> processes the roadway graph to determine that: (<NUM>) the roadway graph indicates that the second road segment is an outgoing road segment that flows from the first road segment; (<NUM>) the road closure state of the first road segment is open; (<NUM>) the road closure state of the second road segment is closed, and (<NUM>) all other outgoing road segments (if any) flowing from the first road segment are closed.

Returning to step <NUM> of the process <NUM> of <FIG>, the resolution module <NUM> can then change the road closure data stored in the mapping platform <NUM> (e.g., in the closure data layer <NUM> of the geographic database <NUM>) to resolve the inconsistency. For example, the resolution module <NUM> can either match the road closure state of the first road segment being evaluated with the road closure state of the second road segment, or match the road closure state of the second road segment with the closure state of the first road segment. In one embodiment, the resolution module <NUM> selects between matching the first road closure state with the second road closure state or matching the second road closure state with the first road closure state based on closure score data calculated for the first road segment, the second road segment, or a combination thereof.

In other words, the resolution module <NUM> can remove any detected inconsistencies by post-processing a closure graph to mark superlinks as closed or open, where it makes sense as described above. In one embodiment, some of the superlinks have been evaluated by an automated verification algorithm and have a closure likelihood score. These superlinks are denoted as "evaluated" superlinks ("E" links). Depending on the closure graph structure, these superlinks are also called either "incoming" ("I" links) or "outgoing" ("O" links). Other superlinks, which have not been evaluated (hence do not have a closure likelihood score), are called only "incoming" ("I" links) or "outgoing" ("O" links) superlinks, depending on the closure graph structure.

In one embodiment, the resolution module <NUM> can use any means to calculate a road closure probability or score. For example, in a road closure verification or detection process, the road closure score can calculated based features derived from the probe data (e.g., GPS probe data) collected from the vehicles traveling on the connected set of road links of the roadway or closure link graph. As described above, the roadway graph includes the road link indicated in a road closure report that is be verified or detected as well as one or more upstream and/or downstream links. In one embodiment, the features can include any characteristic, property, and/or attribute associated with the probe vehicles, road links on which the travel, and/or other related contextual attributes (e.g., time, location, spatial relationship between links, etc.) that can be determined based on the probe data of the roadway graph. Examples of calculating such features are discussed in more detail below.

One example of a feature relates to "through vehicles" associated with the road links of the roadway graph. This feature, for instance, is the total number of vehicles which passed through a given link or superlink of the roadway graph in a given time epoch; e.g. every <NUM> minutes. In one embodiment, the resolution module <NUM> can calculate the through vehicles feature as follows:.

It is noted that this feature is different than GPS probe count on a link or superlink. For example, in contrast to a probe count, a probe that is mis-mapmatched onto the link or superlink is not counted in this feature because the erroneous map-matching would be corrected by the path-based mapmatcher or the extra error correcting logic used in combination with the point-based mapmatching. By similar logic, a vehicle which has no GPS probes on a specific link or superlink would still be counted in this feature if its driving path passes through the link or superlink.

In one embodiment, the resolution module <NUM> can also calculate an "expected through vehicles" feature, which can then be compared against the through vehicles feature calculated above to evaluate the closure probability or score of a road link of interest. The expected through vehicle feature, for instance, is the total number of vehicles expected to pass through a link or superlink for a given epoch (e.g. <NUM> minutes) so that the evaluation of the through vehicles feature to the expected through vehicles feature can be performed for each given time epoch. In one embodiment, the expected through vehicles feature is the summary statistics of the number of through vehicles for that specific time epoch over a historical period (e.g., the same time epoch over a number of days). There are different possibilities to calculate this value, such as but not limited to the following (note that as an example, it is assumed an epoch corresponds to <NUM>-minutes, and there are <NUM> days-worth of historical data):.

In one embodiment, the resolution module <NUM> can also calculate a detouring vehicles feature. A very strong indicator of a closure are vehicles detouring or avoiding a given road segment. This feature calculates number of vehicles detouring around or avoiding a given link or superlink. For example, the detouring vehicles feature can be particularly suited for highways and highway like roads with exit/entry ramps or other entry/exit options to bypass a given road segment or link. In one embodiment, a vehicle is classified as detouring a certain link or superlink if the vehicle is on its way to the evaluated link/superlink, but changes its route away from that link/superlink, drives nearby and re-joins the road which is an extension or continuation of the evaluated link/superlink.

Another set of features for calculating a closure score or probability are based on vehicle speeds. For example, non-zero values for through vehicles feature are an indication of vehicle presence on the road. Yet these vehicles can be construction vehicles doing work on a closed road or emergency vehicles operating at an accident site which is closed to traffic. Therefore, under some scenarios, the through vehicles feature can be misleading on its own. To address this issue, the resolution module <NUM> can calculate a vehicle speed feature (e.g., representing speeds of the probes in the closure link graph). For example, construction vehicles or emergency vehicles operating at a closure site usually have either zero speed values or close to zero speed values. In on embodiment, the feature module <NUM> can use the vehicle speed feature to:.

It is contemplated that the vehicle speed feature can be any characteristic, attribute, property, etc. that is indicative of the speed of a vehicles traveling in the road network of the closure link graph including but not limited to:.

In one embodiment, another feature can be a Closure Report Source Confidence. Incident sources which report closures do not necessarily have the same quality. Some of them are very accurate, whereas others are less. The resolution module <NUM> can take advantage of this information. For example, based on previous performance, incident sources can be assigned a confidence value; the higher the confidence value, the more trusted a source is. In one embodiment, this information could then be used for ambiguous cases; e.g., in the middle of the night a reported superlink which expects to see <NUM> vehicles on average has only one vehicle going through it. In other words, source confidence could be used to decide whether to trust the source or to discard it when verifying road closures or calculating road closure scores.

In one embodiment, temporal features can also be considered. Generally, all of the features described above are calculated for the current epoch (e.g., over probes received in the past <NUM> minutes). However, acting on information received only in the current epoch can be prone for errors. For example, if the epoch is short (e.g., <NUM> minutes), then resulting decisions can be to reactive to noise: the resolution module <NUM> will act on any small change that affects the dynamics of the road network for a few minutes. On the other hand, if the epoch is too long (e.g., <NUM> hour), the algorithm will not react fast to a closure. In one embodiment, to overcome this dilemma, the resolution module <NUM> can calculate the above-mentioned features for a small epoch (e.g., epoch below a time duration threshold such as <NUM> minutes) as well as for a long epoch (e.g., epoch above a time duration threshold such as <NUM> hour). The features determined for both the short and long epochs can then be used alone or in combination to calculate closure score or probability. After calculating the features derived from probe data of roadway graph being monitored or evaluated, the resolution module <NUM> can calculate the closure probability score of the road link of interest based on the calculated features.

As discussed above, in one embodiment, road segments of the roadway graph can then be classified based on whether they have been evaluated (e.g., have a calculated closure probability or score). Links that have a calculated road closure score can be labeled (e.g., labeled as Link E) to differentiate from links that have not been evaluated (e.g., labeled as either Link I for incoming links or Link O for outgoing links). <FIG> illustrates an example of a Structure <NUM> type structure <NUM> (e.g., multiple superlinks flow into only one upstream superlink) that has been labeled to indicate graph conditions as follows:.

In one embodiment, when processing the roadway graphs exhibiting the example structure <NUM>, the resolution module <NUM> selects between matching the road closure state of a first road segment with the road closure state of second and matching the road closure state of the second road segment with the road closure state of the first road segment based calculating a sum of respective closure scores for the second road segment flowing into the first road segment and all other incoming road segments.

<FIG> illustrates a flowchart of an example process for resolving inconsistencies for roadway graphs exhibiting the structure <NUM> of <FIG>, according to one embodiment. In various embodiments, the mapping platform <NUM> and/or any of the modules <NUM>-<NUM> may perform one or more portions of the process <NUM> and may be implemented in, for instance, a chip set including a processor and a memory as shown in <FIG>. As such, the mapping platform <NUM> and/or any of the modules <NUM>-<NUM> can provide means for accomplishing various parts of the process <NUM>, as well as means for accomplishing embodiments of other processes described herein in conjunction with other components of the system <NUM>. Although the process <NUM> is illustrated and described as a sequence of steps, it is contemplated that various embodiments of the process <NUM> may be performed in any order or combination and need not include all of the illustrated steps.

In step <NUM>, the resolution module <NUM> checks if there are any superlinks X which fulfill the superlink graph conditions described above with respect to <FIG>. If yes, the resolution module <NUM> proceeds to step <NUM>. If there are multiple superlinks X in the roadway graph that meet the conditions for structure <NUM> of <FIG> (Structure <NUM> type), each superlink X can be evaluated separately through the process <NUM>. Otherwise, the resolution module <NUM>, takes no further action.

In step <NUM>, the resolution module <NUM> checks if superlink X has any evaluated incoming superlinks, Ek. In other words, the resolution module <NUM> checks whether any of the incoming superlinks has a recorded or stored road closure probability or score. If not, the resolution module <NUM> proceeds to step <NUM> to check unevaluated incoming links.

If yes, the resolution module <NUM> checks whether the closure state of superlink X is closed (step <NUM>), and then checks whether the closures states of all evaluated incoming links Ek are closed (step <NUM>). IF both closure states of superlink X and all evaluated incoming links Ek are closed, the resolution module <NUM> proceeds to step <NUM> to check unevaluated incoming links.

If superlink X is closed, but one or more of the evaluated incoming links Ek are open, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

If the resolution module <NUM> determines that superlink X is open at step <NUM>, and that one or more evaluated incoming links Ek are open at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of incoming links Im to open.

If the resolution module <NUM> determines that superlink X is open at step <NUM>, all evaluated incoming links Ek are closed at step <NUM>, and there is at least one Im superlink at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of unevaluated incoming superlinks Im to open.

If the resolution module <NUM> determines that superlink X is open at step <NUM>, all evaluated incoming links Ek are closed at step <NUM>, and there are no Im superlinks at <NUM>, then the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

At step <NUM>, the resolution module <NUM> checks if superlink X has any unevaluated incoming superlinks, Im. If not, the resolution module <NUM> terminates and takes no further action. If yes, the resolution module <NUM> checks whether superlink X is closed at step <NUM>. If superlinkX is closed, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected and then sets the closure states of all unevaluated incoming superlinks Im to closed (step <NUM>). If superlink X is open, the resolution module sets the closure states of all unevaluated incoming superlinks Im to open (step <NUM>).

In one embodiment, similar resolution processes can be performed for other structures detected in the roadway graph. For example, <FIG> illustrates an example of a Structure <NUM> type structure <NUM> (e.g., multiple superlinks follow into only one upstream superlink) that has been labeled to indicate graph conditions as follows:.

In step <NUM>, the resolution module <NUM> checks if superlink X has any evaluated outgoing superlinks, Ek. In other words, the resolution module <NUM> checks whether any of the outgoing superlinks has a recorded or stored road closure probability or score. If not, the resolution module <NUM> proceeds to step <NUM> to check unevaluated outgoing links.

If yes, the resolution module <NUM> checks whether the closure state of superlink X is closed (step <NUM>), and then checks whether the closures states of all evaluated outgoing links Ek are closed (step <NUM>). IF both closure states of superlink X and all evaluated outgoing links Ek are closed, the resolution module <NUM> proceeds to step <NUM> to check unevaluated outgoing links.

If superlink X is closed, but one or more of the evaluated outgoing links Ek are open, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

If the resolution module <NUM> determines that superlink X is open at step <NUM>, and that one or more evaluated outgoing links Ek are open at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of outgoing links Om to open.

If the resolution module <NUM> determines that superlink X is open at step <NUM>, all evaluated outgoing links Ek are closed at step <NUM>, and there is at least one Om superlink at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of unevaluated outgoing superlinks Om to open.

If the resolution module <NUM> determines that superlink X is open at step <NUM>, all evaluated outgoing links Ek are closed at step <NUM>, and there are no Om superlinks at <NUM>, then the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

At step <NUM>, the resolution module <NUM> checks if superlink X has any unevaluated outgoing superlinks, Om. If not, the resolution module <NUM> terminates and takes no further action. If yes, the resolution module <NUM> checks whether superlink X is closed at step <NUM>. If superlink X is closed, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected and then sets the closure states of all unevaluated outgoing superlinks Om to closed (step <NUM>). If superlink X is open, the resolution module <NUM> sets the closure states of all unevaluated outgoing superlinks Om to open (step <NUM>).

In the examples of <FIG> and <FIG>, the evaluated structures include only on superlink X connected at a node either with one or more incoming links or with one or more outgoing links. However, the embodiments described herein are also applicable to more complex road network structures that include multiple superlinks X connected at the node with multiple incoming or outgoing nodes. <FIG> illustrates an example of a Generalized Structure <NUM> type structure <NUM> where multiple superlinks flow into multiple upstream superlinks Xn) that has been labeled to indicate graph conditions as follows:.

In step <NUM>, the resolution module <NUM> checks if there are any superlinks Xn which fulfill the superlink graph conditions described above with respect to <FIG>. If yes, the resolution module <NUM> proceeds to step <NUM>. Otherwise, the resolution module <NUM>, takes no further action.

In step <NUM>, the resolution module <NUM> checks if superlinks Xn have any evaluated incoming superlinks, Ek. In other words, the resolution module <NUM> checks whether any of the incoming superlinks has a recorded or stored road closure probability or score. If not, the resolution module <NUM> proceeds to step <NUM> to check unevaluated incoming links.

If yes, the resolution module <NUM> checks whether the closure states of all superlinks Xn are closed (step <NUM>), and then checks whether the closures states of all evaluated incoming links Ek are closed (step <NUM>). IF the closure states of all superlinks Xn and all evaluated incoming links Ek are closed, the resolution module <NUM> proceeds to step <NUM> to check unevaluated incoming links.

If all superlinks Xn are closed, but one or more of the evaluated incoming links Ek are open, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

If the resolution module <NUM> determines that at least one of the superlinks Xn is open at step <NUM>, and that one or more evaluated incoming links Ek are open at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of incoming links Im to open.

If the resolution module <NUM> determines that at least one of the superlinks Xn is open at step <NUM>, all evaluated incoming links Ek are closed at step <NUM>, and there is at least one Im superlink at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of unevaluated incoming superlinks Im to open.

If the resolution module <NUM> determines that at least one of the superlinks Xn is open at step <NUM>, all evaluated incoming links Ek are closed at step <NUM>, and there are no Im superlinks at <NUM>, then the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

At step <NUM>, the resolution module <NUM> checks if superlinks Xn have any unevaluated incoming superlinks, Im. If not, the resolution module <NUM> terminates and takes no further action. If yes, the resolution module <NUM> checks whether all superlinks Xn are closed at step <NUM>. If all superlinks Xn are closed, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected and then sets the closure states of all unevaluated incoming superlinks Im to closed (step <NUM>). If at least one superlink Xn is open, the resolution module <NUM> sets the closure states of all unevaluated incoming superlinks Im to open (step <NUM>).

<FIG> illustrates an example of a Generalized Structure <NUM> type structure <NUM> where multiple superlinks flow into multiple upstream superlinks Xn) that has been labeled to indicate graph conditions as follows:.

In step <NUM>, the resolution module <NUM> checks if superlinks Xn have any evaluated outgoing superlinks, Ek. In other words, the resolution module <NUM> checks whether any of the outgoing superlinks has a recorded or stored road closure probability or score. If not, the resolution module <NUM> proceeds to step <NUM> to check unevaluated outgoing links.

If yes, the resolution module <NUM> checks whether the closure states of all superlinks Xn are closed (step <NUM>), and then checks whether the closures states of all evaluated outgoing links Ek are closed (step <NUM>). IF the closure states of all superlinks Xn and all evaluated outgoing links Ek are closed, the resolution module <NUM> proceeds to step <NUM> to check unevaluated outgoing links.

If all superlinks Xn are closed, but one or more of the evaluated outgoing links Ek are open, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

If the resolution module <NUM> determines that at least one of the superlinks Xn is open at step <NUM>, and that one or more evaluated outgoing links Ek are open at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of outgoing links Om to open.

If the resolution module <NUM> determines that at least one of the superlinks Xn is open at step <NUM>, all evaluated outgoing links Ek are closed at step <NUM>, and there is at least one Om superlink at step <NUM>, the resolution module <NUM> proceeds to step <NUM> to change the state of unevaluated outgoing superlinks Om to open.

If the resolution module <NUM> determines that at least one of the superlinks Xn is open at step <NUM>, all evaluated outgoing links Ek are closed at step <NUM>, and there are no Om superlinks at <NUM>, then the resolution module <NUM> determines that an Inconsistency <NUM> has been detected (step <NUM>). Based on the detection of Inconsistency <NUM>, the resolution module <NUM> performs the following:.

At step <NUM>, the resolution module <NUM> checks if superlinks Xn have any unevaluated outgoing superlinks, Om. If not, the resolution module <NUM> terminates and takes no further action. If yes, the resolution module <NUM> checks whether all superlinks Xn are closed at step <NUM>. If all superlinks Xn are closed, the resolution module <NUM> determines that an Inconsistency <NUM> has been detected and then sets the closure states of all unevaluated outgoing superlinks Om to closed (step <NUM>). If at least one of the superlinks Xn is open, the resolution module <NUM> sets the closure states of all unevaluated outgoing superlinks Om to open (step <NUM>).

In one embodiment, after performing inconsistency resolution on road closure data, the mapping platform <NUM> can output the processed data to the road closure data layer <NUM> of the geographic database <NUM> or equivalent data. The mapping platform <NUM> can then provide access to the closure data layer <NUM> to providing mapping services, navigation services, location-based services, and/or any other service using the resolved road closure data.

Returning to <FIG>, in one embodiment, the mapping platform <NUM> has connectivity over a communication network <NUM> to other components of the system <NUM> including but not limited to road closure reports <NUM>, services platform <NUM>, services <NUM>, content providers <NUM>, geographic database <NUM>, and/or vehicles <NUM> (e.g., probes). By way of example, the services <NUM> may also be other third-party services and include traffic incident services (e.g., to report road closures), mapping services, navigation services, travel planning services, notification services, social networking services, content (e.g., audio, video, images, etc.) provisioning services, application services, storage services, contextual information determination services, location-based services, information-based services (e.g., weather, news, etc.), etc. In one embodiment, the services platform <NUM> uses the output (e.g. physical divider predictions) of the mapping platform <NUM> to provide services such as navigation, mapping, other location-based services, etc..

In one embodiment, the mapping platform <NUM> may be a platform with multiple interconnected components. The mapping platform <NUM> may include multiple servers, intelligent networking devices, computing devices, components and corresponding software for providing parametric representations of lane lines. In addition, it is noted that the mapping platform <NUM> may be a separate entity of the system <NUM>, a part of the one or more services <NUM>, a part of the services platform <NUM>, or included within the vehicle <NUM>.

In one embodiment, content providers 107a-<NUM> (collectively referred to as content providers <NUM>) may provide content or data (e.g., including geographic data, parametric representations of mapped features, etc.) to the geographic database <NUM>, the mapping platform <NUM>, the services platform <NUM>, the services <NUM>, and the vehicle <NUM>. The content provided may be any type of content, such as traffic incident content (e.g., road closure reports), map content, textual content, audio content, video content, image content, etc. In one embodiment, the content providers <NUM> may provide content that may aid in the detecting and classifying of road closures or other traffic incidents. In one embodiment, the content providers <NUM> may also store content associated with the geographic database <NUM>, mapping platform <NUM>, services platform <NUM>, services <NUM>, and/or vehicle <NUM>. In another embodiment, the content providers <NUM> may manage access to a central repository of data, and offer a consistent, standard interface to data, such as a repository of the geographic database <NUM>.

In one embodiment, the vehicles <NUM>, for instance, are part of a probe-based system for collecting probe data for detecting traffic incidents and/or measuring traffic conditions in a road network. In one embodiment, each vehicle <NUM> is configured to report probe data as probe points, which are individual data records collected at a point in time that records telemetry data for that point in time. In one embodiment, the probe ID can be permanent or valid for a certain period of time. In one embodiment, the probe ID is cycled, particularly for consumer-sourced data, to protect the privacy of the source.

In one embodiment, a probe point can include attributes such as: (<NUM>) probe ID, (<NUM>) longitude, (<NUM>) latitude, (<NUM>) heading, (<NUM>) speed, and (<NUM>) time. The list of attributes is provided by way of illustration and not limitation. Accordingly, it is contemplated that any combination of these attributes or other attributes may be recorded as a probe point. For example, attributes such as altitude (e.g., for flight capable vehicles or for tracking non-flight vehicles in the altitude domain), tilt, steering angle, wiper activation, etc. can be included and reported for a probe point. In one embodiment, the vehicles <NUM> may include sensors <NUM> for reporting measuring and/or reporting attributes. The attributes can also be any attribute normally collected by an on-board diagnostic (OBD) system of the vehicle, and available through an interface to the OBD system (e.g., OBD II interface or other similar interface). In one embodiment, this data allows the system <NUM> to calculate or construct vehicle paths of a vehicle <NUM> over a stretch of road (e.g., over a closure link graph).

The probe points can be reported from the vehicles <NUM> in real-time, in batches, continuously, or at any other frequency requested by the system <NUM> over, for instance, the communication network <NUM> for processing by the mapping platform <NUM>. The probe points also can be mapped to specific road links stored in the geographic database <NUM>. In one embodiment, the system <NUM> can generate probe traces (e.g., vehicle paths or trajectories) from the probe points for an individual probe so that the probe traces represent a travel trajectory or vehicle path of the probe through the road network.

In one embodiment, the vehicle <NUM> is configured with various sensors <NUM> for generating or collecting vehicular sensor data, related geographic/map data, etc. In one embodiment, the sensed data represent sensor data associated with a geographic location or coordinates at which the sensor data was collected. In this way, the sensor data can act as observation data that can be separated into location-aware training and evaluation datasets according to their data collection locations as well as used for evaluating road closure reports according to the embodiments described herein. By way of example, the sensors may include a radar system, a LiDAR system, a global positioning sensor for gathering location data (e.g., GPS), a network detection sensor for detecting wireless signals or receivers for different short-range communications (e.g., Bluetooth, Wi-Fi, Li-Fi, near field communication (NFC) etc.), temporal information sensors, a camera/imaging sensor for gathering image data, an audio recorder for gathering audio data, velocity sensors mounted on steering wheels of the vehicles, switch sensors for determining whether one or more vehicle switches are engaged, and the like.

Other examples of sensors of the vehicle <NUM> may include light sensors, orientation sensors augmented with height sensors and acceleration sensor (e.g., an accelerometer can measure acceleration and can be used to determine orientation of the vehicle), tilt sensors to detect the degree of incline or decline of the vehicle along a path of travel, moisture sensors, pressure sensors, etc. In a further example embodiment, sensors about the perimeter of the vehicle <NUM> may detect the relative distance of the vehicle from a physical divider, a lane or roadway, the presence of other vehicles, pedestrians, traffic lights, potholes and any other objects, or a combination thereof. In one scenario, the sensors may detect weather data, traffic information, or a combination thereof. In one embodiment, the vehicle <NUM> may include GPS or other satellite-based receivers to obtain geographic coordinates from satellites for determining current location and time. Further, the location can be determined by visual odometry, triangulation systems such as A-GPS, Cell of Origin, or other location extrapolation technologies. In yet another embodiment, the sensors can determine the status of various control elements of the car, such as activation of wipers, use of a brake pedal, use of an acceleration pedal, angle of the steering wheel, activation of hazard lights, activation of head lights, etc..

In one embodiment, the communication network <NUM> of system <NUM> includes one or more networks such as a data network, a wireless network, a telephony network, or any combination thereof. It is contemplated that the data network may be any local area network (LAN), metropolitan area network (MAN), wide area network (WAN), a public data network (e.g., the Internet), short range wireless network, or any other suitable packet-switched network, such as a commercially owned, proprietary packet-switched network, e.g., a proprietary cable or fiber-optic network, and the like, or any combination thereof. In addition, the wireless network may be, for example, a cellular network and may employ various technologies including enhanced data rates for global evolution (EDGE), general packet radio service (GPRS), global system for mobile communications (GSM), Internet protocol multimedia subsystem (IMS), universal mobile telecommunications system (UMTS), etc., as well as any other suitable wireless medium, e.g., worldwide interoperability for microwave access (WiMAX), Long Term Evolution (LTE) networks, code division multiple access (CDMA), wideband code division multiple access (WCDMA), wireless fidelity (Wi-Fi), wireless LAN (WLAN), Bluetooth®, Internet Protocol (IP) data casting, satellite, mobile ad-hoc network (MANET), and the like, or any combination thereof.

By way of example, the mapping platform <NUM>, services platform <NUM>, services <NUM>, vehicle <NUM>, and/or content providers <NUM> communicate with each other and other components of the system <NUM> using well known, new or still developing protocols. In this context, a protocol includes a set of rules defining how the network nodes within the communication network <NUM> interact with each other based on information sent over the communication links. The protocols are effective at different layers of operation within each node, from generating and receiving physical signals of various types, to selecting a link for transferring those signals, to the format of information indicated by those signals, to identifying which software application executing on a computer system sends or receives the information. The conceptually different layers of protocols for exchanging information over a network are described in the Open Systems Interconnection (OSI) Reference Model.

<FIG> is a diagram of a geographic database, according to one embodiment. In one embodiment, the geographic database <NUM> includes geographic data <NUM> used for (or configured to be compiled to be used for) mapping and/or navigation-related services. In one embodiment, geographic features (e.g., two-dimensional or three-dimensional features) are represented using polygons (e.g., two-dimensional features) or polygon extrusions (e.g., three-dimensional features). For example, the edges of the polygons correspond to the boundaries or edges of the respective geographic feature. In the case of a building, a two-dimensional polygon can be used to represent a footprint of the building, and a three-dimensional polygon extrusion can be used to represent the three-dimensional surfaces of the building. It is contemplated that although various embodiments are discussed with respect to two-dimensional polygons, it is contemplated that the embodiments are also applicable to three-dimensional polygon extrusions. Accordingly, the terms polygons and polygon extrusions as used herein can be used interchangeably.

In one embodiment, the following terminology applies to the representation of geographic features in the geographic database <NUM>.

"Node" - A point that terminates a link.

"Line segment" - A straight line connecting two points.

"Link" (or "edge") - A contiguous, non-branching string of one or more line segments terminating in a node at each end.

"Shape point" - A point along a link between two nodes (e.g., used to alter a shape of the link without defining new nodes).

"Oriented link" - A link that has a starting node (referred to as the "reference node") and an ending node (referred to as the "non reference node").

"Simple polygon" - An interior area of an outer boundary formed by a string of oriented links that begins and ends in one node. In one embodiment, a simple polygon does not cross itself.

"Polygon" - An area bounded by an outer boundary and none or at least one interior boundary (e.g., a hole or island). In one embodiment, a polygon is constructed from one outer simple polygon and none or at least one inner simple polygon. A polygon is simple if it just consists of one simple polygon, or complex if it has at least one inner simple polygon.

In one embodiment, the geographic database <NUM> follows certain conventions. For example, links do not cross themselves and do not cross each other except at a node. Also, there are no duplicated shape points, nodes, or links. Two links that connect each other have a common node. In the geographic database <NUM>, overlapping geographic features are represented by overlapping polygons. When polygons overlap, the boundary of one polygon crosses the boundary of the other polygon. In the geographic database <NUM>, the location at which the boundary of one polygon intersects they boundary of another polygon is represented by a node. In one embodiment, a node may be used to represent other locations along the boundary of a polygon than a location at which the boundary of the polygon intersects the boundary of another polygon. In one embodiment, a shape point is not used to represent a point at which the boundary of a polygon intersects the boundary of another polygon.

As shown, the geographic database <NUM> includes node data records <NUM>, road segment or link data records <NUM>, POI data records <NUM>, road closure data records <NUM>, other records <NUM>, and indexes <NUM>, for example. More, fewer or different data records can be provided. In one embodiment, additional data records (not shown) can include cartographic ("carto") data records, routing data, and maneuver data. In one embodiment, the indexes <NUM> may improve the speed of data retrieval operations in the geographic database <NUM>. In one embodiment, the indexes <NUM> may be used to quickly locate data without having to search every row in the geographic database <NUM> every time it is accessed. For example, in one embodiment, the indexes <NUM> can be a spatial index of the polygon points associated with stored feature polygons.

In exemplary embodiments, the road segment data records <NUM> are links or segments representing roads, streets, or paths, as can be used in the calculated route or recorded route information for determination of one or more personalized routes. The node data records <NUM> are end points corresponding to the respective links or segments of the road segment data records <NUM>. The road link data records <NUM> and the node data records <NUM> represent a road network, such as used by vehicles, cars, and/or other entities. Alternatively, the geographic database <NUM> can contain path segment and node data records or other data that represent pedestrian paths or areas in addition to or instead of the vehicle road record data, for example.

The road/link segments and nodes can be associated with attributes, such as geographic coordinates, street names, address ranges, speed limits, turn restrictions at intersections, and other navigation related attributes, as well as POIs, such as gasoline stations, hotels, restaurants, museums, stadiums, offices, automobile dealerships, auto repair shops, buildings, stores, parks, etc. The geographic database <NUM> can include data about the POIs and their respective locations in the POI data records <NUM>. The geographic database <NUM> can also include data about places, such as cities, towns, or other communities, and other geographic features, such as bodies of water, mountain ranges, etc. Such place or feature data can be part of the POI data records <NUM> or can be associated with POIs or POI data records <NUM> (such as a data point used for displaying or representing a position of a city).

In one embodiment, the geographic database <NUM> includes the road closure data records <NUM> for storing inconsistency-resolved road closure data, predicted road closure reports, road closure evaluations, road closure link graphs, associated probe data/vehicle paths, extracted features derived from the probe data, and/or any other related data. The road closure data records <NUM> comprise of the road closure data layer <NUM> that store the automatically generated road closure classifications generated according to the various embodiments described herein. The road closure data layer <NUM> can be provided to other system components or end users to provided related mapping, navigation, and/or other location-based services. In one embodiment, the road closure data records <NUM> can be associated with segments of a road link (as opposed to an entire link). It is noted that the segmentation of the road for the purposes of physical divider prediction can be different than the road link structure of the geographic database <NUM>. In other words, the segments can further subdivide the links of the geographic database <NUM> into smaller segments (e.g., of uniform lengths such as <NUM>-meters). In this way, road closures or other traffic incidents can be predicted and represented at a level of granularity that is independent of the granularity or at which the actual road or road network is represented in the geographic database <NUM>. In one embodiment, the road closure data records <NUM> can be associated with one or more of the node records <NUM>, road segment or link records <NUM>, and/or POI data records <NUM>; or portions thereof (e.g., smaller or different segments than indicated in the road segment records <NUM>) to provide situational awareness to drivers and provide for safer autonomous operation of vehicles.

In one embodiment, the geographic database <NUM> can be maintained by the content provider <NUM> in association with the services platform <NUM> (e.g., a map developer). The map developer can collect geographic data to generate and enhance the geographic database <NUM>. There can be different ways used by the map developer to collect data. These ways can include obtaining data from other sources, such as municipalities or respective geographic authorities. In addition, the map developer can employ field personnel to travel by vehicle along roads throughout the geographic region to observe features (e.g., road closures or other traffic incidents, etc.) and/or record information about them, for example. Also, remote sensing, such as aerial or satellite photography, can be used.

In one embodiment, the geographic database <NUM> include high resolution or high definition (HD) mapping data that provide centimeter-level or better accuracy of map features. For example, the geographic database <NUM> can be based on Light Detection and Ranging (LiDAR) or equivalent technology to collect billions of 3D points and model road surfaces and other map features down to the number lanes and their widths. In one embodiment, the HD mapping data capture and store details such as the slope and curvature of the road, lane markings, roadside objects such as sign posts, including what the signage denotes. By way of example, the HD mapping data enable highly automated vehicles to precisely localize themselves on the road, and to determine road attributes (e.g., learned speed limit values) to at high accuracy levels.

In one embodiment, the geographic database <NUM> is stored as a hierarchical or multilevel tile-based projection or structure. More specifically, in one embodiment, the geographic database <NUM> may be defined according to a normalized Mercator projection. Other projections may be used. By way of example, the map tile grid of a Mercator or similar projection is a multilevel grid. Each cell or tile in a level of the map tile grid is divisible into the same number of tiles of that same level of grid. In other words, the initial level of the map tile grid (e.g., a level at the lowest zoom level) is divisible into four cells or rectangles. Each of those cells are in turn divisible into four cells, and so on until the highest zoom or resolution level of the projection is reached.

In one embodiment, the map tile grid may be numbered in a systematic fashion to define a tile identifier (tile ID). For example, the top left tile may be numbered <NUM>, the top right tile may be numbered <NUM>, the bottom left tile may be numbered <NUM>, and the bottom right tile may be numbered <NUM>. In one embodiment, each cell is divided into four rectangles and numbered by concatenating the parent tile ID and the new tile position. A variety of numbering schemes also is possible. Any number of levels with increasingly smaller geographic areas may represent the map tile grid. Any level (n) of the map tile grid has <NUM>(n+<NUM>) cells. Accordingly, any tile of the level (n) has a geographic area of A/<NUM>(n+<NUM>) where A is the total geographic area of the world or the total area of the map tile grid <NUM>. Because of the numbering system, the exact position of any tile in any level of the map tile grid or projection may be uniquely determined from the tile ID.

In one embodiment, the system <NUM> may identify a tile by a quadkey determined based on the tile ID of a tile of the map tile grid. The quadkey, for example, is a one-dimensional array including numerical values. In one embodiment, the quadkey may be calculated or determined by interleaving the bits of the row and column coordinates of a tile in the grid at a specific level. The interleaved bits may be converted to a predetermined base number (e.g., base <NUM>, base <NUM>, hexadecimal). In one example, leading zeroes are inserted or retained regardless of the level of the map tile grid in order to maintain a constant length for the one-dimensional array of the quadkey. In another example, the length of the one-dimensional array of the quadkey may indicate the corresponding level within the map tile grid <NUM>. In one embodiment, the quadkey is an example of the hash or encoding scheme of the respective geographical coordinates of a geographical data point that can be used to identify a tile in which the geographical data point is located.

For example, geographic data is compiled (such as into a platform specification format (PSF) format) to organize and/or configure the data for performing navigation-related functions and/or services, such as route calculation, route guidance, map display, speed calculation, distance and travel time functions, and other functions, by a navigation device, such as by the vehicle <NUM>, for example. The navigation-related functions can correspond to vehicle navigation, pedestrian navigation, or other types of navigation. The compilation to produce the end user databases can be performed by a party or entity separate from the map developer. For example, a customer of the map developer, such as a navigation device developer or other end user device developer, can perform compilation on a received geographic database in a delivery format to produce one or more compiled navigation databases.

The processes described herein for providing road closure graph consistency resolution may be advantageously implemented via software, hardware (e.g., general processor, Digital Signal Processing (DSP) chip, an Application Specific Integrated Circuit (ASIC), Field Programmable Gate Arrays (FPGAs), etc.), firmware or a combination thereof. Such exemplary hardware for performing the described functions is detailed below.

<FIG> illustrates a computer system <NUM> upon which an embodiment of the invention may be implemented. Computer system <NUM> is programmed (e.g., via computer program code or instructions) to provide road closure graph consistency resolution as described herein and includes a communication mechanism such as a bus <NUM> for passing information between other internal and external components of the computer system <NUM>. Information (also called data) is represented as a physical expression of a measurable phenomenon, typically electric voltages, but including, in other embodiments, such phenomena as magnetic, electromagnetic, pressure, chemical, biological, molecular, atomic, sub-atomic and quantum interactions. For example, north and south magnetic fields, or a zero and non-zero electric voltage, represent two states (<NUM>, <NUM>) of a binary digit (bit). Other phenomena can represent digits of a higher base. A superposition of multiple simultaneous quantum states before measurement represents a quantum bit (qubit). A sequence of one or more digits constitutes digital data that is used to represent a number or code for a character. In some embodiments, information called analog data is represented by a near continuum of measurable values within a particular range.

A processor <NUM> performs a set of operations on information as specified by computer program code related to providing road closure graph consistency resolution. The computer program code is a set of instructions or statements providing instructions for the operation of the processor and/or the computer system to perform specified functions. The code, for example, may be written in a computer programming language that is compiled into a native instruction set of the processor. The code may also be written directly using the native instruction set (e.g., machine language). The set of operations include bringing information in from the bus <NUM> and placing information on the bus <NUM>. The set of operations also typically include comparing two or more units of information, shifting positions of units of information, and combining two or more units of information, such as by addition or multiplication or logical operations like OR, exclusive OR (XOR), and AND. Each operation of the set of operations that can be performed by the processor is represented to the processor by information called instructions, such as an operation code of one or more digits. A sequence of operations to be executed by the processor <NUM>, such as a sequence of operation codes, constitute processor instructions, also called computer system instructions or, simply, computer instructions. Processors may be implemented as mechanical, electrical, magnetic, optical, chemical or quantum components, among others, alone or in combination.

Computer system <NUM> also includes a memory <NUM> coupled to bus <NUM>. The memory <NUM>, such as a random access memory (RAM) or other dynamic storage device, stores information including processor instructions for providing road closure graph consistency resolution. Dynamic memory allows information stored therein to be changed by the computer system <NUM>. RAM allows a unit of information stored at a location called a memory address to be stored and retrieved independently of information at neighboring addresses. The memory <NUM> is also used by the processor <NUM> to store temporary values during execution of processor instructions. The computer system <NUM> also includes a read only memory (ROM) <NUM> or other static storage device coupled to the bus <NUM> for storing static information, including instructions, that is not changed by the computer system <NUM>. Some memory is composed of volatile storage that loses the information stored thereon when power is lost. Also coupled to bus <NUM> is a non-volatile (persistent) storage device <NUM>, such as a magnetic disk, optical disk or flash card, for storing information, including instructions, that persists even when the computer system <NUM> is turned off or otherwise loses power.

Information, including instructions for providing road closure graph consistency resolution, is provided to the bus <NUM> for use by the processor from an external input device <NUM>, such as a keyboard containing alphanumeric keys operated by a human user, or a sensor. A sensor detects conditions in its vicinity and transforms those detections into physical expression compatible with the measurable phenomenon used to represent information in computer system <NUM>. Other external devices coupled to bus <NUM>, used primarily for interacting with humans, include a display device <NUM>, such as a cathode ray tube (CRT) or a liquid crystal display (LCD), or plasma screen or printer for presenting text or images, and a pointing device <NUM>, such as a mouse or a trackball or cursor direction keys, or motion sensor, for controlling a position of a small cursor image presented on the display <NUM> and issuing commands associated with graphical elements presented on the display <NUM>. In some embodiments, for example, in embodiments in which the computer system <NUM> performs all functions automatically without human input, one or more of external input device <NUM>, display device <NUM> and pointing device <NUM> is omitted.

Computer system <NUM> also includes one or more instances of a communications interface <NUM> coupled to bus <NUM>. Communication interface <NUM> provides a one-way or two-way communication coupling to a variety of external devices that operate with their own processors, such as printers, scanners and external disks. In general the coupling is with a network link <NUM> that is connected to a local network <NUM> to which a variety of external devices with their own processors are connected. For example, communication interface <NUM> may be a parallel port or a serial port or a universal serial bus (USB) port on a personal computer. In some embodiments, communications interface <NUM> is an integrated services digital network (ISDN) card or a digital subscriber line (DSL) card or a telephone modem that provides an information communication connection to a corresponding type of telephone line. In some embodiments, a communication interface <NUM> is a cable modem that converts signals on bus <NUM> into signals for a communication connection over a coaxial cable or into optical signals for a communication connection over a fiber optic cable. As another example, communications interface <NUM> may be a local area network (LAN) card to provide a data communication connection to a compatible LAN, such as Ethernet. For wireless links, the communications interface <NUM> sends or receives or both sends and receives electrical, acoustic or electromagnetic signals, including infrared and optical signals, that carry information streams, such as digital data. For example, in wireless handheld devices, such as mobile telephones like cell phones, the communications interface <NUM> includes a radio band electromagnetic transmitter and receiver called a radio transceiver. In certain embodiments, the communications interface <NUM> enables connection to the communication network <NUM> for providing road closure graph consistency resolution.

<FIG> illustrates a chip set <NUM> upon which an embodiment of the invention may be implemented. Chip set <NUM> is programmed to provide road closure graph consistency resolution as described herein and includes, for instance, the processor and memory components described with respect to <FIG> incorporated in one or more physical packages (e.g., chips). By way of example, a physical package includes an arrangement of one or more materials, components, and/or wires on a structural assembly (e.g., a baseboard) to provide one or more characteristics such as physical strength, conservation of size, and/or limitation of electrical interaction. It is contemplated that in certain embodiments the chip set can be implemented in a single chip.

The processor <NUM> and accompanying components have connectivity to the memory <NUM> via the bus <NUM>. The memory <NUM> includes both dynamic memory (e.g., RAM, magnetic disk, writable optical disk, etc.) and static memory (e.g., ROM, CD-ROM, etc.) for storing executable instructions that when executed perform the inventive steps described herein to provide road closure graph consistency resolution. The memory <NUM> also stores the data associated with or generated by the execution of the inventive steps.

<FIG> is a diagram of exemplary components of a mobile terminal (e.g., handset) capable of operating in the system of <FIG>, according to one embodiment. Generally, a radio receiver is often defined in terms of front-end and back-end characteristics. The front-end of the receiver encompasses all of the Radio Frequency (RF) circuitry whereas the back-end encompasses all of the base-band processing circuitry. Pertinent internal components of the telephone include a Main Control Unit (MCU) <NUM>, a Digital Signal Processor (DSP) <NUM>, and a receiver/transmitter unit including a microphone gain control unit and a speaker gain control unit. A main display unit <NUM> provides a display to the user in support of various applications and mobile station functions that offer automatic contact matching. An audio function circuitry <NUM> includes a microphone <NUM> and microphone amplifier that amplifies the speech signal output from the microphone <NUM>. The amplified speech signal output from the microphone <NUM> is fed to a coder/decoder (CODEC) <NUM>.

The MCU <NUM> receives various signals including input signals from the keyboard <NUM>. The keyboard <NUM> and/or the MCU <NUM> in combination with other user input components (e.g., the microphone <NUM>) comprise a user interface circuitry for managing user input. The MCU <NUM> runs a user interface software to facilitate user control of at least some functions of the mobile station <NUM> to provide road closure graph consistency resolution. The MCU <NUM> also delivers a display command and a switch command to the display <NUM> and to the speech output switching controller, respectively. Further, the MCU <NUM> exchanges information with the DSP <NUM> and can access an optionally incorporated SIM card <NUM> and a memory <NUM>. In addition, the MCU <NUM> executes various control functions required of the station. The DSP <NUM> may, depending upon the implementation, perform any of a variety of conventional digital processing functions on the voice signals. Additionally, DSP <NUM> determines the background noise level of the local environment from the signals detected by microphone <NUM> and sets the gain of microphone <NUM> to a level selected to compensate for the natural tendency of the user of the mobile station <NUM>.

An optionally incorporated SIM card <NUM> carries, for instance, important information, such as the cellular phone number, the carrier supplying service, subscription details, and security information. The SIM card <NUM> serves primarily to identify the mobile station <NUM> on a radio network. The card <NUM> also contains a memory for storing a personal telephone number registry, text messages, and user specific mobile station settings.

Claim 1:
A computer-implemented method (<NUM>) to resolve an inconsistency in road closure data (<NUM>) stored in a mapping platform (<NUM>), comprising:
processing map data to generate (<NUM>) a roadway graph (<NUM>) representing a spatial relationship between a first road segment and a second road segment, wherein the first road segment has a first closure state, the second road segment has a second closure state, wherein the first and second closure states are stored in the road closure data and indicate whether the respective road segment is closed or open, wherein the spatial relationship indicates that the first closure state of the first road segment cannot differ from the second closure state of the second road segment;
determining (<NUM>), from the roadway graph and the road closure data, that the inconsistency in the road closure data for the first road segment and the second road segment exists by determining that the first closure state and the second closure state differ, thereby being inconsistent with the spatial relationship, wherein the existence of the inconsistency is based on determining that:
the roadway graph indicates that the second road segment is an incoming road segment that flows into the first road segment,
the first road closure state is open,
the second road closure state is closed, and
any other incoming road segments flowing into the first road segment are closed; or
the roadway graph indicates that the second road segment is an outgoing road segment that flows from the first road segment,
the first road closure state is open,
the second road closure state is closed, and
any other outgoing road segments flowing from the first road segment are closed; and in response to the determined existence of the inconsistency in the road closure data,
changing (<NUM>) the road closure data stored in the mapping platform either to match the first road closure state with the second road closure state, or to match the second road closure state with the first road closure state, so that the first and second road closure states no longer differ.