Space-time correlation-based dynamic fusion early warning method and system for navigation warning information and electronic chart

Abstract

The application provides a dynamic fusion early warning method and system for navigation warning information and electronic sea charts based on space-time correlation. The method comprises the following steps: generating an effective action object by receiving a navigation warning message, generating a future passing range in combination with ship navigation data and an electronic sea chart, calculating a space-time fusion risk index, and performing dynamic fusion early warning when the index exceeds a threshold. The scheme realizes accurate matching of navigation warning information and actual ship navigation situation, and significantly improves the timeliness and reliability of navigation early warning.

Description

Technical Field

[0001] This invention belongs to the field of intelligent maritime electronics, and in particular relates to a method and system for dynamic fusion early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation. Background Technology

[0002] With the development of shipborne communication, electronic chart display and integrated maritime information service technologies, navigation warnings, navigation notices, piracy incident reports and high-risk collision warnings for merchant and fishing vessels can now be accessed in real time by the ship's system through network links, shore-based service platforms or integrated maritime information interfaces, and displayed on electronic charts in a layered overlay manner.

[0003] Existing, relatively similar technical solutions typically involve receiving multi-source navigational warning data from an electronic chart system, parsing its coordinates, area range, issuance time, and text content, and then overlaying the warning objects onto the chart interface in the form of points, lines, or areas. This data is then combined with the vessel's current position, heading, speed, or planned route to calculate the spatial distance, relative bearing, or expected proximity between the vessel and the warning area. When the vessel approaches or is expected to enter the warning area, it triggers audio-visual alerts, pop-up notifications, or detailed displays to assist the navigator in making navigational decisions. Compared to traditional methods relying on manual reading of notices and manual comparison of charts, this approach significantly improves the efficiency of acquiring and displaying navigational warning information and also possesses a certain level of early warning capability.

[0004] However, in practical engineering applications, the above-mentioned solutions still have significant shortcomings. First, existing solutions typically treat navigation warning objects as static geometric areas or ordinary display layers. While this can achieve the above-mentioned display, it is difficult to further form a unified object that can directly participate in subsequent spatiotemporal judgments. Furthermore, navigation warnings themselves have clear time attributes such as effectiveness, expiration, update, extension, and cancellation. The risk impact and advance warning time of different types of navigation warnings on the ship at different effective stages are also different. Therefore, it is easy to issue warnings too early before they take effect, continue to issue warnings after they have expired, or fail to issue timely warnings when a decision is truly needed. Secondly, existing solutions for utilizing electronic charts largely remain at the level of base map display and simple spatial ranging, failing to fully leverage the semantic constraints of charts such as channels, shoals, restricted areas, lane separation schemes, anchorages, and navigable boundaries. Therefore, "geometric proximity" does not necessarily equate to "navigational relevance." When there are impassable waters, channel separations, or conditions requiring detours, alarms unrelated to actual navigation may still be triggered. Furthermore, some risky objects, though not the closest, but located in the ship's subsequent navigable corridor, may not be highlighted sufficiently in a timely manner. Thirdly, during actual navigation, ships are affected by maneuvering actions, collision avoidance behaviors, course changes, and channel conditions. Their future motion is not a completely fixed single trajectory. Judging solely based on the current position or a single path often fails to accurately reflect the ship's potential passage range in the future, leading to false alarms, missed alarms, and insufficient early warning stability. For the reasons mentioned above, it is necessary to propose a dynamic fusion early warning scheme that is more in line with engineering practice. This scheme would enable the system to first organize the original navigation warning information into objects with clear time and space constraints, and then combine the navigation boundaries on the electronic chart with the real-time navigation status of the vessel to determine the vessel's possible future passage range. Subsequently, the system would perform early warning display, layer highlighting, and information push based on the spatiotemporal relationship between the two, thereby improving the pertinence, timeliness, and availability of the fusion navigation warning. Summary of the Invention

[0005] This invention discloses a method and system for dynamic fusion early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the first aspect of the present invention provides a method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation, the method comprising: Receive the original air traffic warning message, extract the air traffic warning spatial range, air traffic warning effective time and air traffic warning type, and generate the effective target of the air traffic warning; Read the ship's real-time navigation data and the information on partially passable waters on the electronic chart, and combine the time phase ratio and the expansion coefficient of the navigation warning category in the effective target of the navigation warning to determine the forward distance and lateral half-width of the ship's future passage corridor; Starting from the current position of the ship and taking the current course as the center axis, a centerline with a length equal to the forward distance is generated. Nodes are taken along the centerline at fixed steps and offset to the left and right by the lateral half-width to generate left and right boundary points. All left and right boundary points are connected and the tail is closed to form an initial polygon. The initial polygon is then trimmed using the navigable water boundary in the electronic chart to obtain the ship's possible future navigability range. Calculate the spatial overlap area between the ship's potential future passage range and the effective target of the navigation warning, combine the time overlap ratio between the ship's future warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio, and generate a spatiotemporal fusion risk index. When the spatiotemporal fusion risk index exceeds the preset warning threshold, a dynamic fusion warning action is executed on the electronic nautical chart. The dynamic fusion warning action includes layer highlighting, generating guide lines, and displaying handling suggestions.

[0007] Further, the process of receiving the original flight warning message, extracting the flight warning spatial range, the effective time of the flight warning, and the flight warning category, and generating the effective target of the flight warning includes: The coordinates in the original flight warning message are converted into a sequence of vertices of a closed polygon, and the effective time and expiration time in the original flight warning message are uniformly converted into UTC second-level time. Based on the current time, the effective time, and the expiration time, calculate the time phase ratio of the effective target of the aviation warning; Based on the aviation warning category, the aviation warning category is converted into an internal category code through a preset mapping table.

[0008] Furthermore, determining the forward distance of the future passage corridor for this vessel by combining the time phase proportion of the effective targets of the navigation warning with the navigation warning category expansion coefficient includes: Obtain the ship's current speed and preset warning time window; Based on the flight warning category expansion coefficient, the time phase ratio, and the heading change, the basic displacement calculated based on the current speed and the preset warning time window is adjusted to obtain the forward distance.

[0009] Furthermore, determining the lateral half-width of the future passageway for this vessel includes: Obtain the minimum width of the locally passable waterway sampled along the current course; The minimum width of the locally passable waterway, the basic lateral offset, the forward distance, the navigation warning category expansion coefficient, and the time stage proportion are substituted into the lateral half-width calculation model to obtain the lateral half-width.

[0010] Furthermore, the generation of left and right boundary points includes: At each node, offset to the left and right by the distance of half the lateral width in a direction perpendicular to the center line; Read the spatial boundary of the effective target of the navigation warning, calculate the bearing of the current ship position to the nearest point of the spatial boundary, and increase the density of discrete nodes on the bearing side.

[0011] Furthermore, the calculation of the spatial overlap area between the vessel's potential future passage range and the effective target of the navigation warning includes: The area of ​​the possible future passage range of this vessel is recorded as the first area, and the area of ​​the effective target of the navigation warning is recorded as the second area; The area of ​​the overlapping region between the two is obtained through the nautical chart space engine and is denoted as the overlapping area. The spatial correlation strength is obtained by dividing the overlapping area by the sum of the first area and the second area and then subtracting the difference in the overlapping area.

[0012] Furthermore, the generation of spatiotemporal fusion risk indicators, which combines the time overlap ratio between the ship's future early warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio, includes: The earlier end time is subtracted from the later start time to obtain the time overlap length. The time overlap length is then divided by the length of the ship's future early warning time window to obtain the time overlap ratio. The spatial overlap area, the temporal overlap ratio, the aviation warning category expansion coefficient, and the time stage ratio are substituted into the risk indicator model to generate a spatiotemporal fusion risk indicator.

[0013] Furthermore, the dynamic fusion early warning action also includes: On the main layer of the electronic chart, redraw the corresponding navigation warning polygon area with a highlight color and a thicker border; Draw a guide line between the ship's current position and the nearest boundary point of the area; The warning window on the right side of the interface displays the flight warning category, remaining validity period, and suggested action text.

[0014] Furthermore, the method also includes: The original aviation warning identifier is used as an interactive index and bound to the highlighted layer object; In response to a user's click on a highlighted layer object, retrieve the original aviation warning information, issuing unit, and update time.

[0015] A second aspect of the present invention provides a dynamic fusion early warning system for navigational warning information and electronic nautical charts based on spatiotemporal correlation, the system comprising: The message access processing unit is used to receive the original flight warning message, extract the flight warning spatial range, flight warning effective time and flight warning type, and generate the effective target of the flight warning. The navigation warning object generation unit is used to read the ship's real-time navigation data and the information on partially passable waters on the electronic chart, and combine the time phase ratio and navigation warning category expansion coefficient in the effective navigation warning object to determine the forward distance and lateral half-width of the ship's future passage corridor. The future passage range generation unit is used to generate a centerline with the current position of the ship as the starting point and the current course as the center axis, with a length equal to the forward distance, to take nodes along the centerline at fixed step sizes and offset to the left and right by the lateral half width to generate left and right boundary points, to connect all left and right boundary points and close the tail to form an initial polygon, and to trim the initial polygon using the passable water boundary in the electronic chart to obtain the possible future passage range of the ship. The spatiotemporal correlation early warning execution unit is used to calculate the spatial overlap area between the ship's future possible passage range and the effective target of the navigation warning, and to generate a spatiotemporal fusion risk index by combining the time overlap ratio between the ship's future early warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio. When the spatiotemporal fusion risk index exceeds the preset early warning threshold, a dynamic fusion early warning action is executed on the electronic chart. The dynamic fusion early warning action includes layer highlighting, generating guide lines, and displaying handling suggestions.

[0016] The beneficial technical effects of the present invention are at least as follows: To address the aforementioned issues, this invention provides a method and system for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation. By establishing a spatiotemporal correlation dynamic fusion mechanism between navigation warning information and electronic nautical charts, it effectively solves the problems of premature or delayed warnings caused by timing mismatch in navigation warnings, spatial judgment distortion caused by relying solely on geometric distance while ignoring navigation semantics, and insufficient stability caused by using only a single path to represent future motion in existing technologies. This solution treats navigation warnings as objects with spatiotemporal constraints and combines them with electronic nautical chart constraints to determine the vessel's potential future passage range. It can accurately determine whether the vessel will enter the actual range of the navigation warning during its effective period, thereby significantly reducing the rate of irrelevant warnings, improving the timeliness and reliability of effective warnings, and enhancing the system's application reliability in real navigation environments. Attached Figure Description

[0017] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0018] Figure 1 This is a flowchart of the dynamic fusion early warning method for navigation warning information and electronic nautical charts based on spatiotemporal correlation, as described in this invention.

[0019] Figure 2This is a framework diagram of the dynamic fusion early warning system for navigation warning information and electronic nautical charts based on spatiotemporal correlation, as described in this invention. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0021] In one or more embodiments, such as Figure 1 As shown, a dynamic fusion early warning method based on spatiotemporal correlation of navigation warning information and electronic nautical charts is disclosed. The method includes the following: S1: Receive the original air traffic warning message, extract the air traffic warning spatial range, effective time and type, and generate the effective target of the air traffic warning.

[0022] Specifically, in step one, the system receives raw navigation warning messages through shipboard integrated communication equipment or shore-based information service interfaces. Access sources are limited to maritime information channels directly related to the scenario described in this solution, including NAVTEX receivers, maritime safety information receiving terminals, AIS security-related broadcast interfaces, satellite communication terminal forwarding interfaces, and shore-based maritime information service platform interfaces. The raw data format after entering the system is typically NMEA text, JSON messages, XML messages, or database records. However, in this step, only three types of content directly related to subsequent warnings are extracted: the navigation warning spatial range, the effective time of the navigation warning, and the navigation warning category. The navigation warning spatial range may be represented as single-point coordinates, a series of polyline coordinates, a sequence of closed polygon vertices, or a textual description of "within a certain number of nautical miles centered on a certain point." The effective time of the navigation warning is usually represented by the effective time and the expiration time, or it may only give the effective time. The navigation warning category comes from the subject identifier in the message, such as piracy risk, high-risk collision, construction restrictions, or temporary navigation bans. After receiving the message, the system first splits and caches the original message, writing the spatial, temporal, category, and message identifier fields into memory structures or temporary database tables for later conversion and tracing. If the message provides single-point coordinates, such as the discovery of pirate activity in a sea area, the system generates a closed region around that point based on a preset minimum radius of influence. If the message provides a linear range, such as the area affected by channel construction or towing operations, the system reads the line segment vertices in sequence and expands along both sides of the line with a preset bandwidth of influence to form a closed strip-shaped region. If the message provides a polygonal region, the system directly reads each vertex, while unifying the vertex order and coordinate reference to ensure consistency with the electronic nautical chart coordinate system. The coordinates here are all latitude and longitude, usually provided directly by the navigation warning agency in the message, with data format in decimal strings or floating-point values, and the unit being degrees. Taking a JSON message sent from a shore-based interface as an example, if it specifies that the four vertices of the risk area are 120.1°E, 22.3°N, 120.6°E, 22.3°N, 120.6°E, 22.7°N, and 120.1°E, 22.7°N, the system will sequentially read these four vertices and check if the beginning and end are closed. If not, the system will automatically fill in the first point, ultimately forming a closed polygon boundary that can be directly used for electronic chart overlay display and subsequent area entry judgment. For messages with missing coordinates, abnormal vertex order, missing time fields, or unrecognizable category fields, the system will mark the message as a record to be verified and will not proceed to subsequent early warning calculations. Only the original identifier and reception time will be retained for manual tracing or subsequent re-parsing, to avoid abnormal messages directly affecting subsequent spatiotemporal correlation judgments.

[0023] After unifying the spatial scope, the system standardizes the flight warning time. The effective and expiration times in the messages are uniformly converted to UTC seconds. The original time comes from the flight warning message itself, and after entering the system, it is converted to an integer or long integer second value by the time parsing module. The current system time is provided by the GNSS timing module, BeiDou timing module, or shipborne master clock, and is uniformly converted to UTC seconds. If the message provides both the effective and expiration times, they are written in their original values. If only the effective time is given, the expiration time is supplemented according to the preset maximum effective duration corresponding to the flight warning category, and the supplementation mark is written to the record. If the message only specifies the release time, the release time is written to the effective time field. or In case of an anomaly, the system marks the flight warning object as an invalid time object and excludes it from the current warning calculation to avoid a zero denominator or inverted time interval in subsequent time ratio calculations. Subsequently, based on the principle of linear normalization in mathematics, the system expresses the current position within the entire valid flight warning interval as a continuous proportional value. The original idea of ​​linear normalization is to obtain the relative position within the interval by subtracting the lower bound from the current value and then dividing by the upper bound minus the lower bound. This step applies this principle to the valid flight warning time interval, mapping the lower bound of the interval to the flight warning activation time, the upper bound to the flight warning deactivation time, and the current value to the system's current time, thus obtaining the following formula: ; in, This represents the current time phase of the aviation warning system and is a dimensionless proportional value. The system time is displayed and is obtained through a GNSS timing module, a BeiDou timing module, or a shipboard master clock, in seconds. This indicates the effective time of the flight warning, obtained by parsing and converting the original flight warning message, and is expressed in seconds. This represents the flight warning failure time, obtained by parsing the original flight warning message or by completing it according to preset rules, and the unit is seconds. Dimensionally, both the numerator and denominator represent the time difference, with the unit being seconds. Therefore, the calculated result... It is a dimensionless proportional quantity with consistent dimensions. This proportional value is used to describe which stage of the effective range the navigation warning is currently in; for example, close to zero indicates that it has just entered the effective stage, and close to one indicates that it has entered the near-end stage. Furthermore, when At that time, it can be Record it as zero and mark it as an inactive stage, when At that time, it can be This is recorded as an expired stage, so that subsequent steps can directly determine whether to continue participating in the warning based on the stage status. A practical calculation scenario can more intuitively illustrate the processing: If a high-risk collision warning's effective time is 8:00:00 on April 21, 2026, and its expiration time is 20:00:00 on April 21, 2026, and the current system time is 11:00:00 on April 21, 2026, then after converting them all to seconds starting from midnight of that day, we can take... It lasts for 28,800 seconds. It is 72,000 seconds. The fraction is 39,600 seconds. Substituting this into the formula, we get the numerator as 10,800 seconds and the denominator as 43,200 seconds. Therefore... A value of 0.25 indicates that the flight warning is currently in the first quarter of the entire effective time interval; if the current system time becomes 18:00:00, then... It is 64,800 seconds. After substituting... Approximately 0.83 indicates that the air traffic warning has entered the latter part of its effective time interval. After completing the time phase ratio calculation, the system then uses a preset mapping table to uniformly convert the categories into internal category codes based on the message subject field. For example, piracywarning, armedrobbery, and suspiciouscraft are classified as pirate risk categories; collisionhotspot and densefishingvessels are classified as high-risk collision categories; and dredging and constructionarea are classified as construction restriction categories. The mapping table is stored in a configuration file or parameter table and is updated by maintenance personnel according to version. At this point, the system generates the only output of this step, namely the effective target of the air traffic warning. . It is a structured record that includes the unified closed space boundary, the standardized effective time, the standardized failure time, and the proportion of time stages. The unified aviation warning categories and original aviation warning identifiers can be stored as database records or in-memory objects. Subsequent processing can directly read them. Complete the spatiotemporal correlation determination between the ship's potential future passage range and the effective range of the navigation warning.

[0024] S2: Read the ship's real-time navigation data and local navigable waters information on the electronic chart, and combine the time phase ratio and navigation warning category expansion coefficient in the effective target of the navigation warning to determine the forward distance and lateral half-width of the ship's future passage corridor.

[0025] Specifically, in step two, the system directly reads the effective targets of the flight warning system output and cached in step one. And fully utilize its aviation warning space boundaries and standardized effective time. Standardized failure time Time phase ratio The system also reads the ship's real-time navigation data, including current position, heading, and speed. The current position is output from the ship's onboard GNSS or BeiDou receiver, and after analysis, latitude and longitude coordinates are obtained in degrees. The heading is output from a gyrocompass or magnetic compass, also in degrees. The speed... Speed ​​is calculated from GPS or measured by a log, in knots (nautical miles per hour). The system also reads the width of locally navigable waters from electronic charts to determine lateral passage constraints. To ensure stability in subsequent calculations, the course change... The preferred method is to calculate the value from a series of consecutive heading samples, and to remove or smooth out any instantaneous jumps exceeding a preset anomaly threshold. The objective of step two is to transform the effective target of the navigation warning generated in step one into two core geometric parameters on the ship's side: the forward distance of the ship's future passage corridor. and horizontal half width This provides direct input for the next step of generating the ship's potential future navigation range.

[0026] In the specific calculations, the system first determines the forward extension dimension of the ship's future passageway. The fundamental basis for this quantity comes from the uniform displacement formula in classical physics, that is, displacement equals velocity multiplied by time. In the maritime scenario, speed is measured in knots, and the preset warning time window is measured in hours; therefore, the basic displacement can be directly written as... To ensure that this forward scale reflects the impact of the air traffic control object on the warning distance, the system superimposes two adjustment terms directly related to the air traffic control scenario onto the base displacement. The first adjustment term is derived from the time phase ratio output in step one. With the expansion coefficient of aviation police category The product of these terms is used to express the amplification effect of different types of air traffic warnings on the advance attention distance at different effective stages; the second adjustment term comes from the change in heading formed by continuous sampling of the current heading. This is used to compress the distance simply pushed outward along the current course when the ship's course changes rapidly. This yields the expression for the forward distance: ; in, Indicates the forward distance of the corridor through which the ship will pass, in nautical miles; This indicates the ship's current speed, calculated from the speed log or GPS, and is expressed in knots. This indicates the preset warning time window, which is derived from the system parameter table and is in hours. Represents the expansion coefficient of the aviation police category, which is... The aviation warning category is read through the parameter mapping table and is a dimensionless parameter. This represents the proportion of the time period for which step one has been calculated, and is a dimensionless proportion value. This represents the change in heading between two consecutive heading samples, obtained by subtracting the continuous output values ​​of the gyrocompass or magnetic compass, and is expressed in degrees. For dimensional verification... The unit is nautical miles per hour. The unit is hours, and the product of the two is nautical miles; , and Both are dimensionless, therefore The unit is nautical mile, and the dimensions are consistent.

[0027] Forward distance Once determined, the system further constructs the horizontal half-width. The electronic nautical chart database contains channel boundaries, shoal areas, restricted navigation zones, and navigable water boundaries. The system samples along the current course at fixed steps to obtain the width of the local navigable water ahead. The unit is nautical miles. At the same time, the system sets the basic lateral offset. The value is given by the system parameter table, and the unit is nautical miles. Combining the navigation warning category and time phase, the system obtains the lateral half-width expression: ; in, This indicates the lateral half-width of the corridor through which the ship will pass, in nautical miles. This represents the minimum width of locally navigable waters sampled along the current course, sourced from an electronic nautical chart database, and is expressed in nautical miles. This represents the basic lateral offset, derived from the system parameter table, and is in nautical miles. The forward distance calculated using the aforementioned formula is expressed in nautical miles. The expansion coefficient for aviation police categories is dimensionless. This represents the time period proportion output from step one, and is dimensionless. Dimensionality checks are performed. , and All units are in nautical miles, and the adjustment term in parentheses is dimensionless. The unit is nautical miles, and the dimension is valid. This formula makes the lateral spread width subject to the combined constraints of the electronic chart's navigable boundary, the ship's forward passage dimensions, and the navigational warning status.

[0028] The calculation process is illustrated with a set of examples. Assume the ship's current speed... It consists of twelve sections, with preset warning time windows. For a period of one hour, the navigation warning category output in step one is pirate risk, with a corresponding category expansion coefficient. Take 0.6, the proportion of the time phase. The difference between two consecutive heading samples is 0.25. If it is 10 degrees, then the forward distance is... Approximately equal to 12 multiplied by 1.15 and then divided by 1.111, the result is approximately 12.42 nautical miles. Let's also assume the local navigable width obtained from electronic chart sampling. The lateral offset of the base is 2.4 nautical miles. Taking 0.6 nautical miles, the target's horizontal half-width is approximately 0.6 plus 0.1 multiplied by 12.42 and then by 1.45, resulting in approximately 2.40 nautical miles. Equal to 1.2 nautical miles, therefore the final value is... The minimum navigable width is 1.2 nautical miles. If the electronic chart fails to retrieve a valid local navigable width at a certain moment, the system will preferably re-sample along several consecutive points ahead to obtain the minimum navigable width. If a valid value still cannot be obtained, the system will revert to using the basic lateral offset. This serves as a temporary lateral half-width. Thus, the system completes the output of this step, which is the forward distance of the ship's future passageway. With horizontal half width These two parameters will serve as the basis for determining the ship's potential future navigation range in the next step. Direct input.

[0029] S3: Starting from the current position of the ship and taking the current course as the center axis, generate a centerline with a length equal to the forward distance. Take nodes along the centerline at fixed steps and offset them to the left and right by the lateral half-width to generate left and right boundary points. Connect all left and right boundary points and close the tail to form an initial polygon. Then, use the navigable water boundary in the electronic chart to trim the initial polygon to obtain the possible future navigability range of the ship.

[0030] Specifically, this step reads the forward distance output from step two. and horizontal half width At the same time, it calls the effective flight warning object that has been generated and cached in step one. Based on the ship's real-time navigation data and navigation constraints information on electronic charts, the possible future passage range of the ship is constructed. .in, Used to determine the forward length of the future passageway for this ship. Used to determine the lateral expansion dimensions of the corridor; The navigation warning spatial boundary is used to determine the geometric sampling density and local electronic chart sampling area in the risk-related direction, while the original navigation warning identifier serves as the basis for subsequent binding relationships. All information is retained. The ship's current position is provided by a GNSS or Beidou receiver, and the latitude and longitude coordinates are obtained through analysis, in degrees. The ship's heading is provided by a gyrocompass or magnetic compass, in degrees. The channel boundaries, shoal areas, restricted navigation areas, and navigable water boundaries in the electronic chart are directly read from the electronic chart database and used to trim the constructed geometry.

[0031] In its implementation, the system first uses the current ship position as the starting point and the current course as the central axis, and then generates a length of [length missing] in the electronic chart coordinate system. The system then uses the centerline as a guide. Subsequently, points are discretely selected along the centerline at fixed step sizes, for example, one node every 0.5 nautical miles. At each node, the system is offset to the left or right along a direction perpendicular to the centerline. The system generates left and right boundary points. To ensure that the vessel's potential future passage range is closer to the relevant directions of the navigation warning, the system simultaneously reads... The spatial boundary is calculated, and the bearing of the nearest point on the current ship position to this spatial boundary is determined. Discrete node density is then increased on this bearing side to refine the boundary representation closer to the risk direction. All port and starboard boundary points are connected in sequence along the centerline and closed at the stern, forming an initial polygon representing the ship's potential future passage range. The fixed step size described here can be set based on the ship's current speed, electronic chart zoom level, and the current warning time window. A smaller step size is used when the speed is high or the warning area is complex to avoid excessively coarse initial polygon boundaries that could lead to distortion in subsequent spatial intersection calculations.

[0032] After the initial polygon is formed, the system clips it using the navigable waterway boundaries on the electronic chart. During clipping, the system performs a spatial intersection operation between the initial polygon and the navigable waterway polygon, retaining only the portion located within the navigable waterway, thus obtaining the final potential future navigability range of the vessel. If the intersection result is empty or only scattered small fragments remain, the system marks the result as having no valid passage range and ends the current round of warning execution to avoid continuing to calculate geometric fragments that have no practical passage significance. The data format is a sequentially arranged sequence of latitude and longitude vertices, in degrees, which can be directly rendered and displayed by the electronic chart engine, or used directly for subsequent spatial calculations. Because... The output of step two has been fully utilized in the construction process. and And through the output of step one The risk-related directions have been constrained and encrypted, so this range is not a geometric extrapolation area in the general sense, but an engineering object that is oriented towards the direction of navigational risks, restricted by the navigation boundaries of electronic nautical charts, and can be directly used for subsequent spatiotemporal correlation determination.

[0033] The construction process is illustrated with a set of embodiments. Assume the forward distance output in step two is... It is 12.42 nautical miles wide and half a mile wide. The distance is 1.2 nautical miles. The ship's current position is 120.0 degrees east longitude and 22.0 degrees north latitude, and the current heading is 90 degrees. The system first generates a centerline of 12.42 nautical miles along the due east direction, then takes a node every 0.5 nautical miles; at each node, it is offset by 1.2 nautical miles in both the north and south directions to obtain the sequence of left and right boundary points. If the output of step one is... If the spatial boundary is located slightly northeast of the ship's forward side, the system increases the sampling density when discretizing the northeastern boundary, making the polygon vertices more densely packed on that side. Subsequently, the system intersects this initial polygon with the navigable waterway boundary on the electronic chart, deleting the boundary portions extending beyond the navigable waterway, ultimately obtaining a closed polygon. The output of this step is the potential passage range for this vessel in the future. This output will serve as the direct spatial input for the next step of executing spatiotemporal correlation dynamic fusion early warning.

[0034] S4: Calculate the spatial overlap area between the ship's potential future passage range and the effective target of the navigation warning, combine the time overlap ratio between the ship's future warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio, to generate a spatiotemporal fusion risk index; when the spatiotemporal fusion risk index exceeds the preset warning threshold, execute a dynamic fusion warning action on the electronic chart, the dynamic fusion warning action includes layer highlighting, generating guide lines and displaying handling suggestions.

[0035] Specifically, in step four, the system directly reads the potential future passage range of the vessel output in step three. And index the effective flight warning object that was generated and cached in step one by the flight warning identifier carried in this range. This unifies the data from both the ship's side and the navigational warning side into the same electronic chart coordinate system and the same time base for dynamic fusion early warning. It is the closed polygon output in step three, whose vertex coordinates are derived from the current ship position, current heading, and forward distance. and horizontal half width The continuous construction results are in the form of a sequentially arranged sequence of latitude and longitude vertices, in degrees. Includes air traffic control space boundaries, polygon vertex sequences, and standardized effective times. Standardized failure time Time phase ratio The fields for flight warning category and original flight warning identifier have already undergone structured processing in previous steps, and therefore directly participate in the correlation calculation in this step. Current system time. The timing information is provided by the GNSS timing module, BeiDou timing module, or shipborne master clock, and the unit is seconds; the preset warning time window has already been used in step two, and is converted to seconds here. This is used for calculating time interval overlap. The entire execution process revolves around a clear objective: to simultaneously determine the spatial overlap between the vessel's potential future passage range and the navigation warning's area of ​​effect, as well as the temporal overlap between the future time window and the effective duration of the navigation warning, on the electronic chart, and to merge these two factors into an execution quantity that can directly drive alarms, layer highlighting, detailed display, and handling suggestions. If the navigation warning has already been marked as inactive or invalid in step one, this step only retains the layer display and does not proceed to the warning execution quantity calculation.

[0036] The system first calculates the spatial association strength. This calculation originates from set similarity theory in mathematics, specifically using the Jaccard similarity coefficient in a geometric region scenario, which is the intersection-union ratio commonly used in engineering. The original idea is to divide the size of the intersection of two sets by the size of their union to obtain a similarity between zero and one. This application applies this principle to two closed polygonal regions on an electronic nautical chart, representing the potential future passage range of the vessel. Effective targets of aviation police The corresponding navigation warning space boundary. The system uses the nautical chart space engine to call a polygon clipping algorithm to find the overlapping area between the two, and its area is denoted as... The unit is square nautical miles; then the area is obtained through the vertex sequence area calculation method. area Area of ​​the aviation police's operational range The unit is square nautical miles. Vertex area calculation in engineering implementation typically uses the classic shoelace formula, performed by the geometric functions built into the chart engine. The input is a sequence of vertices, and the output is the area value. Based on the above quantities, the system constructs the following expression for spatial association strength: ; in, It represents the spatial correlation strength and is a dimensionless proportional value; This indicates the overlapping area between the vessel's potential future passage range and the area of ​​operation of the navigational warning, expressed in square nautical miles. This indicates the area of ​​the vessel's potential passage, expressed in square nautical miles. This represents the area of ​​the navigational warning's effective range, expressed in square nautical miles. The derivation of this formula is straightforward; the denominator contains... The area corresponds to the union of the two regions, therefore the entire fraction equals the area of ​​the intersection divided by the area of ​​the union. In the dimensionless check, both the numerator and denominator are area quantities, and the unit is square nautical miles, therefore the result... It is dimensionless and conforms to the general definition of similarity index.

[0037] After obtaining the spatial correlation strength, the system continues to construct a spatiotemporal fusion risk index. The time component used here is derived from the overlap length calculation principle in interval operations, where the overlap length of two time intervals equals the earlier end time minus the later start time; if the result is negative, it is taken as zero. In this application, one interval is the ship's future early warning time window, corresponding to... The other interval is the effective time interval of the aviation warning, corresponding to... The system first obtains the overlap length of two intervals through interval operations, and then divides it by the length of the ship's future early warning time window. The time overlap ratio is obtained; subsequently, the system introduces an aviation warning category expansion coefficient. The proportion of the time phases already calculated in step one As a weighting term, spatial correlation strength, temporal overlap ratio, and flight warning status weight are integrated into a unified execution quantity. This yields the expression: ; in, This represents a risk indicator for spatiotemporal fusion, expressed as a dimensionless proportional value. This represents the spatial correlation strength calculated using the previous formula; The time of flight warning failure is indicated by the source. The unit is seconds; The system's current time is displayed, sourced from the time synchronization module, and is in seconds. This represents the second value after converting the preset warning time window, which is derived from the system parameter table and is in seconds. The effective time of the aviation warning is indicated by [source]. The unit is seconds; Represents the expansion coefficient of the aviation police category, which is... The aviation warning category is read through the parameter mapping table and is a dimensionless parameter. This represents the proportion of the time period calculated in step one, and is a dimensionless proportion value. During the dimensional check... Since the fraction is dimensionless, and both the numerator and denominator are seconds, the time ratio is dimensionless. The values ​​within parentheses are also dimensionless. The final result is dimensionless, consistent with the engineering meaning of risk indicators. If the calculation result of the time overlap term is zero, it indicates that the ship's future time window does not actually overlap with the effective time interval of the navigation warning, and the system will... It is directly recorded as zero and will not proceed to the subsequent alarm triggering process.

[0038] This calculation process can be fully illustrated with a specific example. Assume that step three outputs the possible future passage range of the vessel. After calculation by the chart engine, the area is 20 square nautical miles, corresponding to the area of ​​the navigation warning zone. The area of ​​the overlap between the two is ten square nautical miles. Given a radius of five square nautical miles, the spatial correlation strength is: Reset the system current time. The preset warning time window is 39,600 seconds, or 11:00:00. It takes 3,600 seconds, or one hour; the effective time of the aviation warning. The flight warning expired after 37,800 seconds, or 10 hours, 30 minutes, and 0 seconds. It is forty-three thousand two hundred seconds, or twelve hours, minutes, and seconds. When substituting this set of values ​​into the time overlap term, first calculate... ,Right now ; then calculate ,Right now Subtracting the two gives 3,600 seconds, therefore the time overlap ratio is... If the aviation warning category corresponds to an expansion coefficient The time phase proportions calculated in step one Then the state weight term is Ultimately, the spatiotemporal fusion risk index was obtained. If the warning execution threshold set in the system parameter table is 0.18, then If the threshold is exceeded, the system immediately executes a dynamic fusion warning action; if the threshold is not exceeded, the system maintains the normal layer display state and does not trigger highlighting or active push notifications. Specifically, the system will display the warning on the main layer of the electronic nautical chart. The corresponding navigation warning polygon area is redrawn with a highlighted color and a bold border. A guide line is drawn between the ship's current position and the nearest boundary point of the area. The navigation warning type, remaining validity time, and suggested action text are displayed in the warning window on the right side of the interface. The remaining validity time is shown through... The calculations are then converted and displayed in minutes or hours; simultaneously, the system will... The original aviation warning identifier is used as an interactive index and bound to the highlighted layer object. When the user clicks on this area, they can retrieve the original aviation warning information, issuing unit, and update time. Therefore, this step converts the output of step three... Compared with the output of step one Spatiotemporal correlation calculations of the same caliber were performed, and the results were directly implemented into dynamic fusion early warning actions on electronic nautical charts. Based on the above processing chain, corresponding message access processing units, navigation warning object generation units, future passage range generation units, and spatiotemporal correlation early warning execution units are set up to form a system corresponding to this method.

[0039] In one or more embodiments, such as Figure 2 As shown, a dynamic fusion early warning system for navigation warning information and electronic nautical charts based on spatiotemporal correlation is disclosed. The system includes: The message access processing unit is used to receive the original flight warning message, extract the flight warning spatial range, flight warning effective time and flight warning type, and generate the effective target of the flight warning. The navigation warning object generation unit is used to read the ship's real-time navigation data and the information on partially passable waters on the electronic chart, and combine the time phase ratio and navigation warning category expansion coefficient in the effective navigation warning object to determine the forward distance and lateral half-width of the ship's future passage corridor. The future passage range generation unit is used to generate a centerline with the current position of the ship as the starting point and the current course as the center axis, with a length equal to the forward distance, to take nodes along the centerline at fixed step sizes and offset to the left and right by the lateral half width to generate left and right boundary points, to connect all left and right boundary points and close the tail to form an initial polygon, and to trim the initial polygon using the passable water boundary in the electronic chart to obtain the possible future passage range of the ship. The spatiotemporal correlation early warning execution unit is used to calculate the spatial overlap area between the ship's future possible passage range and the effective target of the navigation warning, and to generate a spatiotemporal fusion risk index by combining the time overlap ratio between the ship's future early warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio. When the spatiotemporal fusion risk index exceeds the preset early warning threshold, a dynamic fusion early warning action is executed on the electronic chart. The dynamic fusion early warning action includes layer highlighting, generating guide lines, and displaying handling suggestions.

[0040] It is worth noting that the specific workflow of the spatiotemporal correlation-based dynamic fusion early warning system for navigation warning information and electronic nautical charts provided in this embodiment of the invention is the same as that of the spatiotemporal correlation-based dynamic fusion early warning method for navigation warning information and electronic nautical charts described in the above embodiments, and will not be repeated here.

[0041] This invention also provides a spatiotemporally correlated dynamic fusion early warning device for navigation warning information and electronic nautical charts, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the steps described in the above embodiments of the spatiotemporally correlated dynamic fusion early warning method for navigation warning information and electronic nautical charts, for example... Figure 1 The steps S1 to S4 described above; or, when the processor executes the computer program, it implements the functions of each module in the above system embodiments.

[0042] For example, the computer program may be divided into one or more modules, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules may be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program in the spatiotemporal correlation-based dynamic fusion early warning device for navigation warning information and electronic nautical charts.

[0043] The spatiotemporal correlation-based dynamic fusion early warning device for navigation warning information and electronic nautical charts can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. This device may include, but is not limited to, processors and memory. Those skilled in the art will understand that the device may also include input / output devices, network access devices, buses, etc.

[0044] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor. This processor is the control center of the spatiotemporal correlation-based dynamic fusion early warning equipment for navigation warning information and electronic nautical charts, connecting all parts of the equipment via various interfaces and lines.

[0045] The memory can be used to store the computer programs and / or modules. The processor, by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory, realizes various functions of the spatiotemporal correlation-based dynamic fusion early warning device for navigation warning information and electronic nautical charts. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function, etc.; the data storage area may store data created according to the operation of the controller, etc. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital card (SD card), flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.

[0046] The module integrating the spatiotemporal correlation-based navigation warning information and the electronic nautical chart dynamic fusion early warning equipment, if implemented as a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0047] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0048] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for dynamic fusion and early warning of navigational warning information and electronic nautical charts based on spatiotemporal correlation, characterized in that, include: Receive the original air traffic warning message, extract the air traffic warning spatial range, air traffic warning effective time and air traffic warning type, and generate the effective target of the air traffic warning; Read the ship's real-time navigation data and local navigable waters information on electronic charts, and combine the time phase ratio and navigation warning category expansion coefficient in the effective target of the navigation warning to determine the forward distance and lateral half-width of the ship's future passage corridor; Starting from the current position of the ship and taking the current course as the center axis, a centerline with a length equal to the forward distance is generated. Nodes are taken along the centerline at fixed steps and offset to the left and right by the lateral half-width to generate left and right boundary points. All left and right boundary points are connected and the tail is closed to form an initial polygon. The initial polygon is then trimmed using the navigable water boundary in the electronic chart to obtain the ship's possible future navigability range. Calculate the spatial overlap area between the ship's potential future passage range and the effective target of the navigation warning, combine the time overlap ratio between the ship's future warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio, to generate a spatiotemporal fusion risk index. When the spatiotemporal fusion risk index exceeds the preset warning threshold, a dynamic fusion warning action is executed on the electronic nautical chart. The dynamic fusion warning action includes layer highlighting, generating guide lines, and displaying handling suggestions.

2. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The process of receiving the original flight warning message, extracting the flight warning spatial range, effective time, and type, and generating the effective targets of the flight warning includes: The coordinates in the original flight warning message are converted into a sequence of vertices of a closed polygon, and the effective time and expiration time in the original flight warning message are uniformly converted into UTC second-level time. Based on the current time, the effective time, and the expiration time, calculate the time phase ratio of the effective target of the aviation warning; Based on the aviation warning category, the aviation warning category is converted into an internal category code through a preset mapping table.

3. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The determination of the forward distance of the future passage corridor for this vessel, by combining the proportion of time phases in the effective targets of the navigation warning with the navigation warning category expansion coefficient, includes: Obtain the ship's current speed and preset warning time window; Based on the flight warning category expansion coefficient, the time phase ratio, and the heading change, the basic displacement calculated based on the current speed and the preset warning time window is adjusted to obtain the forward distance.

4. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The determination of the lateral half-width of the future passageway for this ship includes: Obtain the minimum width of the locally passable waterway sampled along the current course; The minimum width of the locally passable waterway, the basic lateral offset, the forward distance, the navigation warning category expansion coefficient, and the time stage proportion are substituted into the lateral half-width calculation model to obtain the lateral half-width.

5. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The generation of left and right boundary points includes: At each node, offset to the left and right by the distance of half the lateral width in a direction perpendicular to the center line; Read the spatial boundary of the effective target of the navigation warning, calculate the bearing of the current ship position to the nearest point of the spatial boundary, and increase the density of discrete nodes on the bearing side.

6. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The calculation of the spatial overlap area between the ship's potential future passage range and the effective target of the navigation warning includes: The area of ​​the possible future passage range of this vessel is recorded as the first area, and the area of ​​the effective target of the navigation warning is recorded as the second area; The area of ​​the overlapping region between the two is obtained through the nautical chart space engine and is denoted as the overlapping area. The spatial correlation strength is obtained by dividing the overlapping area by the sum of the first area and the second area and then subtracting the difference in the overlapping area.

7. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The method combines the time overlap ratio between the ship's future early warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio, to generate a spatiotemporal fusion risk indicator, including: The earlier end time is subtracted from the later start time to obtain the time overlap length. The time overlap length is then divided by the length of the ship's future early warning time window to obtain the time overlap ratio. The spatial overlap area, the temporal overlap ratio, the aviation warning category expansion coefficient, and the time stage ratio are substituted into the risk indicator model to generate a spatiotemporal fusion risk indicator.

8. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The dynamic fusion early warning action also includes: On the main layer of the electronic chart, redraw the corresponding navigation warning polygon area with a highlight color and a thicker border; Draw a guide line between the ship's current position and the nearest boundary point of the area; The warning window on the right side of the interface displays the flight warning category, remaining validity period, and suggested action text.

9. The method for dynamic fusion and early warning of navigation warning information and electronic nautical charts based on spatiotemporal correlation according to claim 1, characterized in that, The method further includes: The original aviation warning identifier is used as an interactive index and bound to the highlighted layer object; In response to a user's click on a highlighted layer object, retrieve the original aviation warning information, issuing unit, and update time.

10. A dynamic fusion early warning system for navigational warning information and electronic nautical charts based on spatiotemporal correlation, characterized in that, include: The message access processing unit is used to receive the original flight warning message, extract the flight warning spatial range, flight warning effective time and flight warning type, and generate the effective target of the flight warning. The navigation warning object generation unit is used to read the ship's real-time navigation data and the local navigable water information on the electronic chart, and combine the time phase ratio and navigation warning category expansion coefficient in the effective navigation warning object to determine the forward distance and lateral half-width of the ship's future passage corridor. The future passage range generation unit is used to generate a centerline with the current position of the ship as the starting point and the current course as the center axis, with a length equal to the forward distance, to take nodes along the centerline at fixed step sizes and offset to the left and right by the lateral half width to generate left and right boundary points, to connect all left and right boundary points and close the tail to form an initial polygon, and to trim the initial polygon using the passable water boundary in the electronic chart to obtain the possible future passage range of the ship. The spatiotemporal correlation early warning execution unit is used to calculate the spatial overlap area between the ship's possible future passage range and the effective target of the navigation warning, and generate a spatiotemporal fusion risk index by combining the time overlap ratio between the ship's future early warning time window and the effective time interval of the navigation warning, as well as the navigation warning category expansion coefficient and time stage ratio. When the spatiotemporal fusion risk index exceeds the preset warning threshold, a dynamic fusion warning action is executed on the electronic nautical chart. The dynamic fusion warning action includes layer highlighting, generating guide lines, and displaying handling suggestions.

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