Ship AIS identity conflict detection method, device and equipment

Abstract

The invention discloses a ship AIS identity conflict detection method, device and equipment, and the method comprises the following steps: obtaining a target ship AIS message, and determining an environment adaptation factor in a current environment according to current environment factor data, a ship type and an environment adaptation factor calculation model; according to the environmental adaptation factor, the ship type and the forward ocean current component of the target ship corresponding to the ocean current speed, determining the dynamic reachable boundary distance of the target ship under the AIS message time difference; according to the actual positions of the target ship before and after the AIS message time difference, whether the target ship exceeds a dynamic reachable boundary is judged; and if the target ship exceeds the dynamic reachable boundary, determining the conflict probability of the target ship according to the exceeding distance, and determining whether the target ship is an identity falsely-used ship or not. By combining and considering environmental factors such as ocean current, wind speed and sea wave height, whether the target ship exceeds a reasonable range is dynamically judged, whether identity conflicts exist or not is effectively judged, and meanwhile the false alarm situation caused by the environmental factors is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of ship identity detection, and in particular to a method, device and equipment for detecting ship AIS identity conflict. Background Art

[0002] As the core infrastructure of modern maritime communications and navigation, the Automatic Identification System (AIS) plays an irreplaceable role in enhancing ship situational awareness, ensuring navigation safety, and strengthening maritime supervision. It automatically broadcasts key information such as a ship's identity, position, course, and speed, enabling it to identify and track surrounding vessels. However, the current AIS system has significant security vulnerabilities, with identity conflicts (i.e., multiple ships claiming the same identity) and malicious identity disguises (i.e., ships impersonating or forging identity information) becoming increasingly common. Such problems seriously disrupt normal maritime traffic order, significantly weakening the maritime regulatory authorities' ability to identify and track maritime targets, and posing a major threat to navigation safety, potentially leading to errors in collision avoidance decisions and even serious maritime traffic accidents.

[0003] To address the issues of AIS identity conflict and camouflage, existing technologies are mainly based on rule detection with preset thresholds, such as judging sudden changes in ship speed or abnormal position jumps. Although these methods have achieved certain results, they still have fundamental limitations and shortcomings. The main reason is that the above-mentioned existing methods are difficult to dynamically adapt to complex changes in the marine environment (such as ocean currents, wind and waves, traffic density fluctuations, etc.), resulting in insufficient robustness of the detection model. Furthermore, existing detection algorithms are usually too complex to compute and have slow detection speeds, making it difficult to meet the urgent need for real-time identity conflict warnings in high-traffic and complex waters. Ship trajectory deviations or instantaneous distortion of AIS data caused by environmental interference (such as strong currents, strong winds and waves) are often misjudged by existing methods as identity conflicts or camouflage behaviors, resulting in significant false alarm problems.

[0004] In summary, existing technologies are not ideal for detecting AIS identity conflicts, which greatly restricts maritime safety and regulatory efficiency. Therefore, a new technical solution is urgently needed. Summary of the Invention

[0005] The present application provides a method, device and equipment for detecting conflict in ship AIS identities, which can solve the problem in the prior art of difficulty in quickly completing the initial focus of ink droplets on an observation camera.

[0006] In a first aspect, an embodiment of the present application provides a method for detecting a ship AIS identity conflict, which adopts the following technical solution:

[0007] A method for detecting a ship AIS identity conflict comprises the following steps:

[0008] After receiving the target ship's AIS message, the environmental adaptability factor of the target ship when sailing in the current environment is determined based on the current environmental factor data, the target ship's type, and a preset environmental adaptability factor calculation model; wherein the environmental factor data includes at least ocean current speed, wind speed, and wave height;

[0009] Determining the dynamic reachable boundary distance of the target ship under the AIS message time difference based on the environmental adaptability factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship;

[0010] determining whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message;

[0011] If the dynamic reachable boundary is exceeded, determining a collision probability of the target ship based on the dynamic reachable boundary distance and the exceeded distance;

[0012] According to the conflict probability, it is determined whether the target ship is a ship with an identity fraudulently used.

[0013] In combination with the first aspect, in one embodiment, after the AIS message of the target ship is obtained, the following formula is adopted based on the current environmental factor data, the type of the target ship, and the preset environmental adaptation factor calculation model:

[0014]

[0015] Where,

[0016] C: Current ocean current speed (knots), C max : The largest ocean current in the history of this sea area;

[0017] W: current wind speed (m / s), W max : Ship wind resistance level;

[0018] T: wave height (meters), T max : Upper limit of ship seaworthiness;

[0019] w1: ocean current adaptive weight coefficient;

[0020] w2: wind speed adaptive weight coefficient;

[0021] w3: Wave adaptive weight coefficient.

[0022] In conjunction with the first aspect, in one embodiment, the dynamic reachable boundary distance of the target ship within two or more AIS message intervals is determined based on the environmental adaptability factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship, using the following formula:

[0023]

[0024] Where,

[0025] R boundary : Dynamic reachable boundary;

[0026] V type : Base speed of target ship type;

[0027] △ t : Message time difference;

[0028] α: environmental adaptation factor;

[0029] C proj(t) : ocean current projection component at time t;

[0030] β: wind sensitivity coefficient, β = 0.1·L / B, L is the ship length, B is the ship width.

[0031] In conjunction with the first aspect, in one embodiment, the collision probability of the target ship is determined according to the dynamic reachable boundary distance and the exceeded distance, using the following formula:

[0032]

[0033] Where,

[0034] P conflict : conflict probability;

[0035] d exceed : The actual displacement exceeds the boundary distance (nautical miles).

[0036] R boundary : Dynamic reachable boundary distance (nautical miles).

[0037] d exceed / (0.1R boundary ): Normalizes the exceedance distance to a proportion of the dynamic reachable frontier.

[0038] exp(d exceed / (0.1R boundary )): Calculates the value of the exponential decay function, which represents the contribution of the exceeding distance to the collision probability.

[0039] In combination with the first aspect, in one embodiment, in determining whether the target ship is an identity-fraudulent ship based on the conflict probability, when the conflict probability is greater than 0.9, the target ship is determined to be an identity-fraudulent ship.

[0040] In conjunction with the first aspect, in one embodiment, the method further includes the following steps:

[0041] Determine the target ship's speed data within multiple time windows based on the target ship's AIS message;

[0042] determining the behavior entropy of the target ship based on the speed data of the target ship in multiple time windows, multiple speed intervals determined based on the ship type, and a preset ship behavior fingerprint model;

[0043] Determining whether the behavior entropy is greater than a set threshold;

[0044] If it is greater than, it is determined that the target ship has abnormal behavior and an abnormal behavior prompt signal is output.

[0045] In combination with the first aspect, in one embodiment, the behavior entropy of the target ship is determined based on the speed data of the target ship in multiple time windows, multiple speed intervals determined based on the ship type, and a preset ship behavior fingerprint model, using the following formula:

[0046]

[0047] Where,

[0048] p(si): the probability that the speed data corresponding to multiple time windows fall into the i-th interval;

[0049] n: The number of speed intervals, adjusted according to the ship type.

[0050] In conjunction with the first aspect, in one embodiment, after determining whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message, the following steps are further included:

[0051] If the behavior entropy is greater than the set threshold, the target ship has not exceeded the dynamic reachable boundary, and the abnormal behavior of the target ship is recorded;

[0052] If the behavior entropy is less than a set threshold, the target ship exceeds the dynamic reachable boundary, and a first-level alarm signal is output for the target ship;

[0053] If the behavior entropy is greater than a set threshold, the target ship exceeds the dynamic reachable boundary, and a secondary alarm signal for the target ship is output.

[0054] In a second aspect, an embodiment of the present application provides a device for detecting a ship AIS identity conflict, which adopts the following technical solution:

[0055] A ship AIS identity conflict detection device, comprising:

[0056] An environmental module is configured to, upon receiving an AIS message from a target vessel, determine the environmental adaptability factor of the target vessel when navigating in the current environment based on current environmental factor data, the target vessel type, and a preset environmental adaptability factor calculation model; wherein the environmental factor data includes at least ocean current velocity, wind speed, and wave height;

[0057] a boundary calculation module configured to determine a dynamic reachable boundary distance of the target ship under the AIS message time difference based on the environmental adaptation factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship;

[0058] The judgment module is configured to judge whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message; if it exceeds the dynamic reachable boundary, determine the collision probability of the target ship based on the dynamic reachable boundary distance and the excess distance; and determine whether the target ship is an identity-fraudulent ship based on the collision probability.

[0059] In a third aspect, an embodiment of the present application provides a ship AIS identity conflict detection device, which adopts the following technical solution:

[0060] A ship AIS identity conflict detection device includes a processor, a memory, and a ship AIS identity conflict detection program stored in the memory and executable by the processor. When the ship AIS identity conflict detection program is executed by the processor, the steps of the ship AIS identity conflict detection method described above are implemented.

[0061] The beneficial effects of the technical solutions provided in the embodiments of the present application include:

[0062] The ship AIS identity conflict detection method, device and equipment provided in this application can realize users of this solution, such as ships at sea and monitoring centers on shore. By taking into account environmental factors such as ocean currents, wind speed and wave height, it can dynamically determine whether the target ship has exceeded the reasonable range of normal driving, and then effectively determine whether there is an identity conflict based on the position of the target ship, while reducing the occurrence of false alarms caused by environmental factors. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 This is a schematic diagram of the overall process of an embodiment of the ship AIS identity conflict detection method of the present application;

[0064] Figure 2 This is a schematic diagram of the functional modules of an embodiment of the ship AIS identity conflict detection device of the present application;

[0065] Figure 3 This is a schematic diagram of the hardware structure of the ship AIS identity conflict detection device involved in the embodiment of the present application. DETAILED DESCRIPTION

[0066] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0067] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0068] In a first aspect, an embodiment of the present application provides a method for detecting ship AIS identity conflict.

[0069] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the ship AIS identity conflict detection method of this application. Figure 1 As shown, the ship AIS identity conflict detection method includes:

[0070] S100: After obtaining an AIS message from a target vessel, determining an environmental adaptability factor for the target vessel when navigating in the current environment based on current environmental factor data, the target vessel type, and a preset environmental adaptability factor calculation model; wherein the environmental factor data includes at least ocean current velocity, wind speed, and wave height;

[0071] Specifically, in this embodiment, the following formula is adopted:

[0072]

[0073] Where,

[0074] C: Current ocean current speed (knots), C max : The largest ocean current in the history of this sea area;

[0075] W: current wind speed (m / s), W max : Ship wind resistance level;

[0076] T: wave height (meters), T max : Upper limit of ship seaworthiness;

[0077] w1: ocean current adaptive weight coefficient;

[0078] w2: wind speed adaptive weight coefficient;

[0079] w3: Wave adaptive weight coefficient.

[0080] Among them, w1, w2, and w3 are all adaptive weight coefficients related to the ship type and are adjusted according to the ship type. For example, when the ship type is an oil tanker, w1 = 0.4; w2 = 0.3; w3 = 0.3; when the ship type is a container ship: w1 = 0.3; w2 = 0.4; w3 = 0.3; when the ship type is a fishing boat, w1 = 0.4; w2 = 0.2; w3 = 0.4.

[0081] S200, determining a dynamic reachable boundary distance of the target ship based on the AIS message time difference according to the environmental adaptability factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship;

[0082] Specifically, in this embodiment, the following formula is used:

[0083]

[0084] Where,

[0085] R boundary : Dynamic reachable boundary, reflecting the legal range of positions to which the target ship can move between two AIS messages under the influence of the environment;

[0086] V type : Base speed of target ship type;

[0087] △ t : Message time difference, which is the time difference between two AIS messages sent by the target ship;

[0088] α: environmental adaptation factor;

[0089] C proj(t) : The projection component of the ocean current at time t, that is, the effective velocity component of the ocean current in the direction of the target ship's navigation;

[0090] β: wind sensitivity coefficient, β = 0.1·L / B, L is the length of the target ship, and B is the width of the target ship.

[0091] S300, judging whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message;

[0092] S400: If the target ship exceeds the dynamically reachable boundary, determine a collision probability of the target ship based on the dynamically reachable boundary distance and the exceeded distance;

[0093] Specifically, in this embodiment, the following formula is adopted:

[0094]

[0095] Where,

[0096] P conflict : conflict probability;

[0097] d exceed : The actual displacement exceeds the boundary distance (nautical miles).

[0098] R boundary : Dynamic reachable boundary distance (nautical miles).

[0099] d exceed / (0.1R boundary ): Normalizes the exceedance distance to a proportion of the dynamic reachable frontier.

[0100] exp(d exceed / (0.1R boundary )):where exp represents the natural exponential function, and the value of the exponential decay function is calculated, which represents the contribution of the exceeding distance to the collision probability.

[0101] The above formula is used to calculate the collision probability when the target ship position exceeds the dynamic reachable boundary. Specifically, it evaluates the beyond distance d by an exponential decay function. exceed and the dynamic reachability frontier R boundary , thus obtaining a probability between 0 and 1.

[0102] S500: Determine whether the target ship is an identity-misusing ship based on the conflict probability.

[0103] Specifically, when d exceed When it is close to 0, d exceed / (0.1R boundary ) is close to 1, so P conflict A value close to 0 indicates no conflict.

[0104] When P conflict When d increases, exceed / (0.1R boundary ) decreases, so P conflict As , ...

[0105] When P conflict Much larger than R boundary When d exceed / (0.1R boundary ) is close to 0, so P conflict Close to 1, indicating high conflict.

[0106] In this embodiment, it is preferred that when P conflict When >0.9, it is considered as fraudulent use.

[0107] Finally, the user of this solution may be, for example, a ship at sea, which is used for self-security monitoring or communication with other ships; or it may be a monitoring center on shore, which may be a maritime department, used for port management, security monitoring or judicial evidence collection. Steps S100-S500 of this application can be used to dynamically determine whether the target ship exceeds the reasonable range of normal driving by taking into account environmental factors such as ocean currents, wind speed and wave height, thereby effectively determining whether there is an identity conflict based on the position of the target ship and reducing the occurrence of false alarms caused by environmental factors.

[0108] In addition, considering that when a ship (especially a ship sailing at a constant speed) is maliciously impersonated, traditional detection methods often fail or have significant delays. In order to analyze the movement behavior of the ship and achieve effective identity conflict detection, the present application further provides the following steps in some embodiments:

[0109] S600, determining the speed data of the target ship in multiple time windows according to the AIS message of the target ship;

[0110] Specifically, let's assume the time window is set to 5 minutes. This means that every 5 minutes, the ship's speed changes over that period are observed. For example, between 0 and 5 minutes, the ship's speed is 10 knots, 12 knots, and 15 knots. Five minutes later, the next time window is opened, and the speed changes between 5 and 10 minutes may be 15 knots, 18 knots, and 20 knots. After another 5 minutes, the speed changes between 10 and 15 minutes are observed, and so on. Using time windows allows for dynamic and continuous observation of ship speed changes, rather than focusing solely on the speed at a specific point in time. This allows for better capture of ship behavior patterns, such as sudden acceleration or deceleration.

[0111] S700, determining the behavior entropy of the target ship based on the speed data of the target ship in multiple time windows, multiple speed intervals determined based on the ship type, and a preset ship behavior fingerprint model;

[0112] Specifically, in this embodiment, step S700 adopts the following formula:

[0113]

[0114] Where,

[0115] p(si): the probability that the speed data corresponding to multiple time windows fall into the i-th interval;

[0116] n: the number of speed intervals, adjusted according to the ship type;

[0117] wi : Ship type adaptive weight coefficient.

[0118] The calculation method of p(si) is as follows:

[0119] f100. For a specific ship, extract speed data from its AIS message and select a speed range from the speed range library based on the ship type.

[0120] f200. Count the number of times the ship's speed value falls into each interval, and then calculate the probability of each interval.

[0121] For example, consider a ship with speed data of 10, 12, 15, 18, 20, 15, 12, 10, 15, 18. The speed intervals are defined as [10, 12), [12, 15), [15, 18), [18, 20]. The statistical results are: the speed data falls into the interval [10, 12) 2 times; the interval [12, 15) 3 times; the interval [15, 18) 3 times; and the interval [18, 20) 2 times. Therefore, the probability of falling into the i-th interval is calculated as: the number of times the speed data falls into the interval / the total number of speed data. For example, the probability of the first speed interval is p(s1) = 2 / 10 = 0.2; and so on.

[0122] The speed range library is specifically obtained by analyzing the data collected from multiple ports in the past year and combining it with empirical values. It can be simply divided into the following categories for reference:

[0123] 1. Oil Tankers:

[0124] The speed of an oil tanker is usually relatively stable, with a small range of variation. Therefore, a smaller number of speed intervals can be used. The number of speed intervals for an oil tanker can be set to 5. Example speed intervals: [10, 12), [12, 14), [14, 16), [16, 18), [18, 20).

[0125] 2. Container Ship:

[0126] A container ship's speed range may be slightly greater than that of an oil tanker, so more speed intervals are needed to more accurately reflect its behavior. The number of speed intervals for a container ship can be set to 7. Example speed intervals: [10,12), [12,14), [14,16), [16,18), [18,20), [20,22), [22,24).

[0127] 3. Fishing Vessels:

[0128] Fishing boats can experience more frequent and complex speed changes, as they frequently adjust their speed to meet the demands of their fishing operations. Therefore, more speed intervals are needed to capture these changes. The number of speed intervals for a fishing boat can be set to 9. Examples of speed intervals include: [5,7), [7,9), [9,11), [11,13), [13,15), [15,17), [17,19), [19,21), [21,23).

[0129] S800: Determine whether the behavior entropy is greater than a set threshold;

[0130] S900: If it is greater than, determine that the target ship has abnormal behavior and output an abnormal behavior prompt signal.

[0131] Specifically, in this embodiment, when the behavior entropy value is greater than the set threshold of 3.5 bits, it indicates abnormal speed fluctuation, and it is determined that the target ship has abnormal behavior, and a behavior abnormality prompt signal is output.

[0132] At the same time, in order to make the abnormality detection of the target ship more accurate, the present application further provides the following steps:

[0133] S9100: If the behavior entropy is greater than the set threshold, the target ship has not exceeded the dynamic reachable boundary, and the abnormal behavior of the target ship is recorded;

[0134] S9200: If the behavior entropy is less than the set threshold, the target ship exceeds the dynamic reachable boundary, and a level 1 alarm signal is output for the target ship;

[0135] S9300: If the behavior entropy is greater than the set threshold, the target ship exceeds the dynamic reachable boundary, and a secondary alarm signal is output for the target ship.

[0136] Ultimately, the abnormality judgment of the target ship is realized, mainly based on the judgment results of the dynamic reachable range, and further combined with behavioral entropy for auxiliary judgment to improve the accuracy of abnormality judgment.

[0137] In addition, in order to smoothly receive the AIS message of the target ship and perform continuous calculation and judgment based on the subsequent AIS messages of the ship, this application will first determine whether the MMSI of the message has been registered after obtaining the new original AIS message. If it is not registered, a new behavioral fingerprint file will be created for the AIS message to facilitate the subsequent update of the behavioral fingerprint of the ship, so that the relevant data of the ship over a period of time can be called for subsequent calculation, analysis and judgment in the execution of subsequent judgments.

[0138] After it is subsequently determined that the target ship has not exceeded the dynamically reachable boundary, the behavioral fingerprint file of the target ship will be further updated. For the target ship that is determined to have exceeded the dynamically reachable boundary, a data evidence package will also be generated based on its behavioral fingerprint file.

[0139] In a second aspect, an embodiment of the present application further provides a ship AIS identity conflict detection device.

[0140] In one embodiment, referring to Figure 2 , Figure 2 This is a functional module diagram of an embodiment of the ship AIS identity conflict detection device of the present application. Figure 2 As shown, the ship AIS identity conflict detection device includes:

[0141] An environmental module is configured to, upon receiving an AIS message from a target vessel, determine the environmental adaptability factor of the target vessel when navigating in the current environment based on current environmental factor data, the target vessel type, and a preset environmental adaptability factor calculation model; wherein the environmental factor data includes at least ocean current velocity, wind speed, and wave height;

[0142] a boundary calculation module configured to determine a dynamic reachable boundary distance of the target ship under the AIS message time difference based on the environmental adaptation factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship;

[0143] The judgment module is configured to judge whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message; if it exceeds the dynamic reachable boundary, determine the collision probability of the target ship based on the dynamic reachable boundary distance and the excess distance; and determine whether the target ship is an identity-fraudulent ship based on the collision probability.

[0144] The functional implementation of each module in the above-mentioned ship AIS identity conflict detection device corresponds to each step in the above-mentioned ship AIS identity conflict detection method embodiment, and their functions and implementation processes are not repeated here one by one.

[0145] In a third aspect, an embodiment of the present application provides a ship AIS identity conflict detection device, which may be a device with data processing capabilities, such as a personal computer (PC), a laptop computer, or a server.

[0146] Reference Figure 3 , Figure 3Schematic diagram of the hardware structure of the ship AIS identity conflict detection device involved in the embodiment of the present application. In the embodiment of the present application, the ship AIS identity conflict detection device may include a processor, a memory, a communication interface and a communication bus.

[0147] The communication bus may be of any type and is used to interconnect the processor, memory, and communication interface.

[0148] Communication interfaces include input / output (I / O) interfaces, physical interfaces, and logical interfaces, used to interconnect components within the ship's AIS identity conflict detection device, as well as interfaces used to interconnect the device with other devices (such as other computing devices or user equipment). Physical interfaces can include Ethernet, fiber optic, and ATM interfaces; user equipment can include displays, keyboards, and other devices.

[0149] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0150] The processor may be a general-purpose processor that can invoke a ship AIS identity conflict detection program stored in a memory and execute the ship AIS identity conflict detection method provided in the embodiments of the present application. For example, the general-purpose processor may be a central processing unit (CPU). The method executed when the ship AIS identity conflict detection program is invoked can be referenced to the various embodiments of the ship AIS identity conflict detection method of the present application and will not be further described here.

[0151] Those skilled in the art will understand that Figure 3 The hardware structure shown in the figure does not constitute a limitation to the present application and may include more or fewer components than shown in the figure, or a combination of certain components, or a different arrangement of components.

[0152] In a fourth aspect, an embodiment of the present application also provides a storage medium.

[0153] The storage medium of the present application stores a ship AIS identity conflict detection program, wherein when the ship AIS identity conflict detection program is executed by a processor, the steps of the ship AIS identity conflict detection method as described above are implemented.

[0154] Among them, the method implemented when the ship AIS identity conflict detection program is executed can refer to the various embodiments of the ship AIS identity conflict detection method of the present application, and will not be repeated here.

[0155] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0156] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit the "first", "second" and "third" to different types.

[0157] In the description of the embodiments of this application, the words "exemplary," "for example," or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary," "for example," or "for example" in the embodiments of this application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary," "for example," or "for example" is intended to present the relevant concepts in a concrete manner.

[0158] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0159] In some processes described in the embodiments of the present application, multiple operations or steps are included that appear in a specific order. However, it should be understood that these operations or steps may not be performed in the order in which they appear in the embodiments of the present application or may be performed in parallel. The sequence numbers of the operations are only used to distinguish between different operations, and the sequence numbers themselves do not represent any order of execution. In addition, these processes may include more or fewer operations, and these operations or steps may be performed in sequence or in parallel, and these operations or steps may be combined.

[0160] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, of course, it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for enabling a terminal device to execute the methods described in each embodiment of the present application.

[0161] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for detecting conflict in ship AIS identity, characterized in that: It includes the following steps: After receiving the target ship's AIS message, the environmental adaptability factor of the target ship when sailing in the current environment is determined based on the current environmental factor data, the target ship's type, and a preset environmental adaptability factor calculation model; wherein the environmental factor data includes at least ocean current speed, wind speed, and wave height; Determining the dynamic reachable boundary distance of the target ship under the AIS message time difference based on the environmental adaptability factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship; determining whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message; If the dynamic reachable boundary is exceeded, determining a collision probability of the target ship based on the dynamic reachable boundary distance and the exceeded distance; According to the conflict probability, it is determined whether the target ship is a ship with an identity fraudulently used.

2. The ship AIS identity conflict detection method according to claim 1, characterized in that: After obtaining the AIS message of the target ship, the following formula is adopted according to the current environmental factor data, the type of the target ship and the preset environmental adaptation factor calculation model: Where, C: Current ocean current speed (knots), C max : The largest ocean current in the history of this sea area; W: current wind speed (m / s), W wax : Ship wind resistance level; T: wave height (meters), T max : Upper limit of ship seaworthiness; w1: ocean current adaptive weight coefficient; w2: wind speed adaptive weight coefficient; w3: Wave adaptive weight coefficient.

3. The ship AIS identity conflict detection method according to claim 2, characterized in that: The dynamic reachable boundary distance of the target ship within two or more AIS message intervals is determined based on the environmental adaptability factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship, using the following formula: Where, R boundary : Dynamic reachable boundary; V type : Base speed of target ship type; △ t : Message time difference; α: environmental adaptation factor; C proj(t) : ocean current projection component at time t; β: wind sensitivity coefficient, β = 0.1·L / B, L is the ship length, B is the ship width.

4. The ship AIS identity conflict detection method according to claim 3, wherein: In determining the collision probability of the target ship according to the dynamic reachable boundary distance and the exceeded distance, the following formula is adopted: Where, P conflict : conflict probability; d exceed : The actual displacement exceeds the boundary distance (nautical miles). R boundary : Dynamic reachable boundary distance (nautical miles). d exceed / (0.1R boundary ): Normalizes the exceedance distance to a proportion of the dynamic reachable frontier. exp(d exceed / (0.1R boundary )): Calculates the value of the exponential decay function, which represents the contribution of the exceeding distance to the collision probability.

5. The ship AIS identity conflict detection method according to claim 4, characterized in that: In determining whether the target ship is an identity-fraudulent ship based on the conflict probability, when the conflict probability is greater than 0.9, the target ship is determined to be an identity-fraudulent ship.

6. The ship AIS identity conflict detection method according to claim 5, characterized in that: The following steps are also included: Determine the target ship's speed data within multiple time windows based on the target ship's AIS message; determining the behavior entropy of the target ship based on the speed data of the target ship in multiple time windows, multiple speed intervals determined based on the ship type, and a preset ship behavior fingerprint model; Determining whether the behavior entropy is greater than a set threshold; If it is greater than, it is determined that the target ship has abnormal behavior and an abnormal behavior prompt signal is output.

7. The ship AIS identity conflict detection method according to claim 6, characterized in that: The behavior entropy of the target ship is determined based on the speed data of the target ship in multiple time windows, multiple speed intervals determined based on the ship type, and a preset ship behavior fingerprint model, using the following formula: Where, p(si): the probability that the speed data corresponding to multiple time windows fall into the i-th interval; n: The number of speed intervals, adjusted according to the ship type.

8. The ship AIS identity conflict detection method according to claim 7, characterized in that: After determining whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message, the method further includes the following steps: If the behavior entropy is greater than the set threshold, the target ship has not exceeded the dynamic reachable boundary, and the abnormal behavior of the target ship is recorded; If the behavior entropy is less than a set threshold, the target ship exceeds the dynamic reachable boundary, and a first-level alarm signal is output for the target ship; If the behavior entropy is greater than a set threshold, the target ship exceeds the dynamic reachable boundary, and a secondary alarm signal for the target ship is output.

9. A ship AIS identity conflict detection device, characterized in that: It includes: An environmental module is configured to, upon receiving an AIS message from a target vessel, determine the environmental adaptability factor of the target vessel when navigating in the current environment based on current environmental factor data, the target vessel type, and a preset environmental adaptability factor calculation model; wherein the environmental factor data includes at least ocean current velocity, wind speed, and wave height; a boundary calculation module configured to determine a dynamic reachable boundary distance of the target ship under the AIS message time difference based on the environmental adaptation factor, the basic speed corresponding to the ship type, and the downstream current component of the current current speed corresponding to the target ship; The judgment module is configured to judge whether the target ship exceeds the dynamic reachable boundary based on the actual position of the target ship before and after the time difference of the AIS message; if it exceeds the dynamic reachable boundary, determine the collision probability of the target ship based on the dynamic reachable boundary distance and the excess distance; and determine whether the target ship is an identity-fraudulent ship based on the collision probability.

10. A ship AIS identity conflict detection device, characterized in that: The ship AIS identity conflict detection device includes a processor, a memory, and a ship AIS identity conflict detection program stored in the memory and executable by the processor, wherein when the ship AIS identity conflict detection program is executed by the processor, the steps of the ship AIS identity conflict detection method according to claims 1 to 8 are implemented.

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