Patent Description:
As a prior art of the present technical field, <CIT> (Patent Literature <NUM>) is available. In this publication, it is described that "a ship-land intercommunication system includes an on-board information processing apparatus <NUM> disposed in the ship <NUM> for collecting on-board data necessary for the operation management of the ship <NUM> and for sending the on-board data to a marine satellite communication apparatus <NUM>. The ship-land intercommunication system also includes a land-based information processing apparatus <NUM> for processing a predetermined information processing to the on-board data which is sent via the marine satellite communication apparatus <NUM>. The on-board information processing apparatus <NUM> comprises a server equipment <NUM>, an engine monitor panel data logger processing apparatus <NUM>, and the marine satellite communication apparatus <NUM>. The processing apparatus <NUM> collects data necessary for the operation management of the ship and converts the collected data into a numerical data. The converted numerical data is taken into the server equipment <NUM>, and the data is processed and stored therein, and then the data is sent to the marine satellite communication apparatus <NUM> as on-board data in the ship (see a summary).

In addition, <CIT> (Patent Literature <NUM>) is available. In this publication, it is described that "a method includes a step of taking in and recording a ship information of at least an engine section of the operated ship into an on-board personal computer <NUM> automatically as a ship information, a step of inputting and storing the recorded data into a data server <NUM> of a system management company <NUM> which is disposed on a land side via a communication satellite <NUM>, and a step of enabling to access to the data server <NUM> from an authorized client computer <NUM> on a land side via the Internet so as to brows the ship information (see summary).

<CIT>, <CIT>, <NPL> and <CIT> disclose methods and systems for ship movement-sharing navigation support.

According to the above-mentioned Patent Literature <NUM>, a mechanism for transmitting the on-board data acquired from various sensors in the ship to the land-based communication facility by using the satellite communication is described. Also, according to the above-mentioned Patent Document <NUM>, a mechanism for taking in the ship information of the engine section of the ship into the on-board computer in the ship, inputting the data to the land-side data server via the communication satellite, and enabling to browse the data from the client personal computer is described. However, according to both literatures <NUM> and <NUM>, only a configuration which needs an expensive electronic equipment installed on the ship is described, and there is no disclosure of utilizing an inexpensive and simple portable user terminal such as a smartphone or a tablet terminal instead of that.

It is therefore an object of the present invention to provide a Ship Movement-Sharing Navigation Support System utilizing an inexpensive and simple portable user terminal such as a smart phone or a tablet terminal.

In order to solve the above-mentioned problems, for example, a configuration described in the claims is adopted.

The present application includes a plurality of means for solving the above-mentioned problems, and as an example thereof, a method for navigating a ship is provided. The method comprises receiving a first position information and a second position information from a management server having a storage means for storing the first position information of a first ship and the second position information of a second ship wherein the first position information is received via a mobile telephone network from a user terminal used in the first ship and the second position information is transmitted via VHF radio from an AIS (Automatic Identification System) device used in the second ship and received via an AIS system, wherein the user terminal comprises a radar display module and a map display module; displaying an icon indicating the first ship at a position designated by the first position information on a nautical chart, and an icon indicating the second ship at a position designated by the second position information on the nautical chart; displaying a track of the position indicated by the first position information of the first ship and a track of the position indicated by the second position information of the second ship for a predetermined period from past to present; setting a warning area as a fan-shaped area having a first center angle and a radius corresponding to a first distance in the moving direction of the ship and setting a caution area as a fan-shape area having a second center angle larger that the first center angle and a radius corresponding to a second distance in the moving direction shorter than the first distance; and displaying a notification of caution or a notification of warning in a case where the caution area or the warning area of the first ship overlaps the caution area or the warning area of the second ship; displaying the notification of caution by the radar display module and the map display module when the caution area of the first ship and the caution area of the second ship overlap with each other; and displaying the notification of warning by the radar display module and the map display module when the warning area of the first ship and the warning area of the second ship overlap with each other, wherein an importance level and an emergency level of the notification of warning are higher than those of the notification of caution.

In a preferred embodiment a method for navigating a ship, comprising:.

In a preferred embodiment the method for navigating the ship, comprising:.

In a preferred embodiment the method for navigating the ship, comprising:
displaying a predicted moving route of the first ship in future which is calculated based on a track of the first position information for a predetermined second time period in past.

In a preferred embodiment the method for navigating the ship, wherein the predicted moving route of the first ship in future is displayed by a curve.

In a preferred embodiment the method for navigating the ship, comprising:
displaying a predicted moving route of the second ship in future which is calculated based on a speed information of the second ship received from the AIS system.

In a preferred embodiment the method for navigating the ship, comprising:
receiving a selection of a destination on the nautical chart from a user, and displaying at least one of required time and distance to the destination.

In a preferred embodiment the method for navigating the ship, wherein one or more of concentric circles centered on the icon indicating the first ship is displayed on the nautical chart, and the position of the icon indicating the first ship is fixedly displayed in a screen by moving the nautical chart in a direction opposite to the moving direction of the first ship in a case where the first ship moves.

In a preferred embodiment the method for navigating the ship, wherein the track of the first position information is displayed in a case where the first ship enters within any of the one or more of the concentric circles.

In a preferred embodiment the method for navigating the ship, wherein a notification of warning is displayed in a case where the predicted moving route of the first ship and the predicted moving route of other ship cross with each other within a predetermined time.

In a preferred embodiment the method for navigating the ship, wherein a notification of warning is displayed in a case where the predicted moving route of the first ship and the predicted moving route of the second ship cross with each other within a predetermined time.

In a preferred embodiment the method for navigating the ship, comprising:
calculating and displaying a time until the predicted moving route of the first ship and the predicted moving route of the second ship cross with each other.

In a preferred embodiment the method for navigating the ship, comprising:
displaying a predicted arriving position of the first ship on the predicted moving route of the first ship up to the time of crossing.

In a preferred embodiment the method for navigating the ship, wherein the first center angle is determined based on a potential area of ships passing each other according to Prevention of Collision at Sea Act.

In a preferred embodiment the method for navigating the ship, wherein the first center angle is in a range of <NUM> to <NUM> degrees.

In a preferred embodiment the method for navigating the ship, wherein the second center angle is determined based on a potential area of outsailing ships according to Prevention of Collision at Sea Act.

In a preferred embodiment the method for navigating the ship, wherein the second center angle is <NUM> degrees.

According to the method of the invention, the notification of caution is displayed in a case where the caution area and the warning area overlap.

A ship navigation program, wherein the program is configured to perform each step of the method according to the invention on the user terminal.

A management server for use in a ship navigation system, comprising:.

In a preferred embodiment the icon indicating the first ship is displayed at a position corresponding to a time on the track of the first position information in a case where the designation of time is accepted by operation of slider bar from the user.

In a preferred embodiment the transmitting means transmits an information for displaying a predicted moving route of the first ship in future based on the track of the first position information in past predetermined second period to the second user terminal.

In a preferred embodiment the predicted moving route of the first ship in future is displayed by a curve.

In a preferred embodiment the transmitting means transmits a speed information of the second ship received from the AIS system for displaying the predicted moving route of the second ship in future to the second user terminal.

In a preferred embodiment at least one of required time and distance to a destination on the nautical chart received from the user is displayed.

In a preferred embodiment the management server, comprising:.

In a preferred embodiment one or more of concentric circles centered on the icon indicating the first ship is displayed on the nautical chart of the second user terminal, and the position of the icon indicating the first ship is fixedly displayed in a screen by moving the nautical chart in a direction opposite to the moving direction of the first ship in a case where the first ship moves.

In a preferred embodiment the track of the first position information is displayed in a case where the first ship enters within any of the one or more of the concentric circles.

In a preferred embodiment the management server, comprising a collision judgement module for displaying a notification of warning to a user terminal in the first ship in a case where the predicted moving route of the first ship and the predicted moving route of other ship cross with each other within a predetermined time.

In a preferred embodiment the management server, comprising a collision judgement module for displaying a notification of warning to a user terminal in the first ship in a case where the predicted moving route of the first ship and the predicted moving route of the second ship cross with each other within a predetermined time period.

In a preferred embodiment the collision judgement module calculates and displays a time until the predicted moving route of the first ship and the predicted moving route of the second ship cross with each other.

In a preferred embodiment the collision judgement module displays the predicted arriving position of the first ship on the predicted moving route of the first ship up to a time of crossing.

The management server of the invention is adapted to.

In a preferred embodiment the first center angle is determined based on a potential area of ships passing each other according to Prevention of Collision at Sea Act.

In a preferred embodiment the first center angle is in a range of <NUM> to <NUM> degrees.

In a preferred embodiment the second center angle is determined based on a potential area of outsailing ships according to Prevention of Collision at Sea Act.

In a preferred embodiment the second center angle is <NUM> degrees.

In accordance with the invention, the collision judgement module displays the notification of the caution in a case where one caution area and other caution area overlap, and displays the notification of the warning in a case where one warning area and other warning area overlap.

In accordance with the invention, the collision judgement module displays the notification of the warning notification in a case where the caution area and the warning area overlaps.

It is possible to provide a Ship Movement-Sharing Navigation Support System utilizing an inexpensive and simple portable user terminal such as a smart phone or a tablet terminal.

Other problems, configurations and effects other than those described above will be clarified by the following description of the embodiment.

Embodiments will be described below with reference to the drawings.

Heretofore, an electronic equipment used for ships is expensive, and an application, a permission, and a maintenance are required for disposing the electronic equipment in a ship. At the maintenance and repairing for maintaining the electronic equipment, the equipment needs to be handed over to specialists and a large cost may arise from that. Furthermore, a training or taking a course for acquiring its operation (a training which charges an admission fee) may be required.

Examples of the electronic equipment include a radar, a GPS (Global Positioning System) plotter, an AIS (Automatic Identification System: automated ship identification device), an anemometer, an international VHF (Very High Frequency: ultrashort wave) radio (wireless system) and the like. It is necessary to purchase each electronic equipment individually so that a unified operability for them is difficult to obtain.

In addition, the AIS needs to be installed on a ship or passenger vessel for international voyages and on a ship or vessel for non-international voyages with a gross tonnage of <NUM> tons or more. The AIS is an analog radio device which can transmit data in a wireless system. For example, an identification code of a ship that sails, a ship's name, a position of a ship and the like are included in the data. The AIS is convenient in that it can display received data on an electronic nautical chart or a radar screen. However, since the AIS is expensive and large, it is often not disposed on a small ship such as a pleasure boat and the like.

On the other hand, according to a ship navigational system (Ship Movement-Sharing Navigation Support System) <NUM> of the present embodiment, functions of main electronic equipment for conventional small ships are realized on a cloud using loT and/or Al, and an information of all ships, a weather information, a surrounding information and the like are shared in real time via the Internet. By displaying the information on a tablet or smartphone, it becomes possible to solve problems that have been barriers for having the electronic equipment for individuals, such as the cost for introducing, maintaining, and updating the electronic equipment, the temporal cost for obtaining and applying the licenses thereof, the cost of learning for acquiring operations thereof, the training which charges an admission fee and the like. Therefore, it becomes possible to realize a safe and comfortable marine life by using the system <NUM>.

According to the embodiment, an example of displaying an information of ships on a nautical chart on the user terminal will be described.

<FIG> illustrates an example of a configuration diagram of a ship navigational system <NUM> as a whole.

The ship navigational system <NUM> includes a plurality of user terminals <NUM> and a plurality of land-based management terminals <NUM>, and each terminal is connected to the management server <NUM> via a network. This system is implemented by installing an appropriate application (application program) on a tablet or smartphone. Therefore, a mobile telephone communication (or a data communication based on a SIM (Subscriber Identity Module) card) is used as a network for being accessed from the user terminals which are used on ships at sea. It is possible to connect the user terminals to the Wi-Fi (registered trademark) in the ships so as to communicate with the management server <NUM> via the Wi-Fi. The onboard Wi-Fi may be connected to a land-based network by using satellites or the like.

The connection between the land-based management terminal <NUM> and the management server <NUM> may be performed by using a radio network (wireless network) or a wired network. Each terminal may transmit and receive the information over the network.

The user terminal <NUM> is, for example, a tablet, a smart phone or the like which is possible to be brought into and/or disposed on a small ship or the like. In this specification, the small ship may refer to a ship which is mainly called a pleasure boat for the purpose of leisure or sports such as a motorboat, a yacht or a water motorcycle which can be used by individual. The user terminal <NUM> is configured to transmit and receive data to and from the management server <NUM>, the land-based management terminal <NUM>, and other user terminals <NUM> based on, for example, the data communication by using the mobile telephone communication.

The land-based management terminal <NUM> is, for example, a device such as a personal computer or the like which can be disposed in a shipping company of owning small ships or commercial ships, or in a land-based company such as a construction company or a leisure company. The land-based company may provide services that use ships, and may perform an operation for managing ships by using the land-based management terminal <NUM> together with the service management.

The AIS system <NUM> has a mechanism in which an individual information (for example, an identification code, a ship's name, a position, a route, a ship speed, a destination and the like of the own ship) may be transmitted from the AIS device mounted on a ship based on wireless communication by using VHF radio waves, and the individual information may be received by other ships sailing or navigating in the vicinity of the own ship or a marine traffic center located on land.

Each terminal or the management server <NUM> used in the ship navigational system <NUM> is not limited to the above-mentioned examples. For example, the terminal or the server may be a portable terminal such as a smartphone, a tablet, a mobile phone or a portable telephone, or personal digital assistants (PDAs), or a wearable terminal such as an eyeglass type terminal, a wrist watch type terminal or a cloth type terminal. A stationary or portable computer, or a server located on a cloud or network may also be used for them. Furthermore, a combination of a plurality of terminals may be used for them. For example, a combination of one smartphone and one wearable terminal may logically function as one terminal. In addition, an information processing terminal other than these types may be used.

Each terminal and the management server <NUM> used in the ship navigational system <NUM> includes a processor for executing an operating system, an application, a program or the like; a main storage device (memory) such as a RAM (Random Access Memory); an auxiliary storage device such as an IC card, a hard disk drive, an SSD (Solid State Drive), a flash memory or the like; a communication control unit such as a network card, a radio (wireless) communication module, a mobile communication module or the like; an input device such as a touch panel, a keyboard, a mouse, a voice input, a motion detection device based on captured images of camera unit or the like; and an output device such as a monitor or a display. Note that the output device may be a device or a terminal for transmitting an information to be output to an external monitor, a display, a printer, a device, or the like.

Various programs and applications (modules) and the like are stored in the main memory, and each functional element of the entire system is realized when the processor executes these programs and applications. Note that each of these modules may be implemented by using a hardware on which the modules are integrated. Each module may be an independent program or application, but it may be implemented in a form of a single integrated program or some sub-programs or functions in the application.

In this specification, each module is described as a subject which may perform the processings, but in practice, a processor for processing various programs, applications (modules) and the like may be used to execute the processings.

Various databases (DB) are stored in the auxiliary storage device. In this specification, a "database" may be a functional element (storage unit) that stores a data set so as to accommodate any data manipulation (e.g., extraction, addition, deletion or overwriting of data) performed by a processor or an external computer. The method of implementing the database is not limited, and it may use, for example, a database management system, a spreadsheet software, or a text file such as XML.

<FIG> illustrates an example of a hardware configuration of the management server <NUM>.

The management server <NUM> is configured, for example, by using a server which is arranged on a cloud.

The main storage device (memory) <NUM> stores programs and applications such as a map display module <NUM>, a radar display module <NUM>, a plot setting and display module <NUM>, a route plan setting module <NUM>, a weather information display module <NUM>, a radio (wireless) module <NUM>, a collision judgement module <NUM>, and the like. When the processor <NUM> executes these programs and applications, the functional elements of the management server <NUM> are implemented.

The map display module <NUM> is configured to read a navigation information <NUM>, such as an AIS information <NUM> and a user terminal navigation information <NUM> which are transmitted from each ship and stored in the auxiliary storage device <NUM>. Then, the map display module <NUM> processes a necessary information, transmits the processed information to the user terminal <NUM> and/or the land-based management terminal <NUM> so as to display the ship information and other related information on the nautical chart.

The radar display module <NUM> is configured to read a navigation information <NUM>, such as an AIS information <NUM> and a user terminal navigation information <NUM> which are transmitted from each ship and stored in the auxiliary storage device <NUM>. The radar display module <NUM> is also configured to process a necessary information and transmit the processed information to the user terminal <NUM> and/or the land-based management terminal <NUM> so as to display the ships information and other related information in a display form of radar device.

The plot setting and display module <NUM> is configured to store a useful information, an obstacle information, a fishing implement installation area information and the like at an arbitrary position on the nautical chart to be used by the user. By tapping an arbitrary position on the nautical chart which is displayed on a tablet or smartphone and by inputting an information by the user, it becomes possible to store the information in the plot management information <NUM> and to display the information on other user terminals <NUM> using the ship navigational system <NUM> and/or on the land-based management terminals <NUM>.

The route plan setting module <NUM> is configured to be used by the user or the land-based management terminal user to input the ship's navigation plan. By setting a destination and/or a transit point on the nautical chart, it becomes possible to display the route to the destination, the distance thereof, the required time thereof and the like thereon. The inputted information is stored in the route management information <NUM> and it becomes possible to perform the navigation according to the route management information <NUM>.

The weather information display module <NUM> is configured to change or shape the weather management information <NUM> obtained from the Meteorological Agency or other weather-related organizations into a required shape for the ship and display it on the user terminal <NUM> and/or the land-based management terminal <NUM>. Furthermore, the information on wind force, wind direction, wave force and the like may be used to calculate the time required for the navigation plan and to calculate a moving route (a predicted moving route) of the ship.

The radio module <NUM> is configured to provide a virtual radio function (wireless function) by implementing the functions of the international VHF wireless in terms of application by software means (virtually). By packetizing a voice information instead of the VHF radio waves and by transmitting and receiving it by using a data communication such as a mobile telephone network, it becomes possible to realize a call function or communication function on a smartphone or tablet as if by the VHF radio equipment. The setting information related to the virtual radio is stored in the radio management information <NUM>.

When a ship in which the user terminal <NUM> having the ship navigational system <NUM> is used travels on a route where there is a possibility to collide with other ships or the like, the collision judgement module <NUM> displays a caution alert or warning alert on a screen of the management server <NUM>, the user terminal <NUM> or the land-based management terminal <NUM>. There may be many small ships which are not equipped with the AIS equipment on the sea. However, by installing the application of the ship navigational system <NUM> according to the present embodiment on the smartphones or tablets used in the ships in advance, the users of the ships are able to predict the possibility to collide with other ships or the like in terms of the cautio alert or warning alert. As a result, even in this case, it becomes possible to prevent a marine accident.

The navigation information storage module <NUM> is configured to store the user terminal navigation information <NUM> in the user terminal navigation information <NUM> of the navigation information management DB <NUM> collectively wherein the user terminal navigation information <NUM> includes the position information sequentially transmitted from a plurality of user terminals <NUM>. In addition, the navigation information storage module <NUM> is configured to store the AIS information in the AIS information <NUM> of the navigation information management DB wherein the AIS information includes the position information of the AIS-equipped ships acquired from the AIS system <NUM>.

A master information management DB <NUM>, a navigation information management DB <NUM> and a support information management DB <NUM> are stored in the auxiliary storage device <NUM>. The master information management DB <NUM> stores the user management information <NUM> for managing users, the ship management information <NUM> for managing ships, and the radio management information <NUM> for setting the virtual radio.

The navigation information management DB <NUM> stores the navigation information <NUM> including the user terminal navigation management information <NUM> received from the user terminals <NUM>, and the AIS information <NUM> received from the large ships and the like.

The support information management DB <NUM> stores the plot management information <NUM> for storing the plot information, the route management information <NUM> for storing the route plan, and the weather management information <NUM> for storing the weather information.

The various modules may calculate the position, the navigation state and the like of the ships by analyzing and processing various types of information stored in the auxiliary storage device <NUM>, and output and display the results on the respective terminals and/or output devices.

<FIG> illustrates an example of hardware configuration of the user terminal <NUM>.

The user terminal <NUM> is configured by, for example, a tablet, a smart phone or the like.

The main storage device <NUM> stores programs and applications such as a map display module <NUM>, a radar display module <NUM>, a plot setting and display module <NUM>, a route plan setting module <NUM>, a weather information display module <NUM>, a radio module <NUM>, a collision judgement module <NUM> and the like. When the processor <NUM> executes these programs and applications, each functional element of the user terminal <NUM> is realized.

The map display module <NUM> is configured to process the navigation information <NUM> of other ships sent from the management server <NUM> and the information acquired from the own user terminal <NUM> or the own ship, and to display the ships and other related information on the nautical chart.

The radar display module <NUM> is configured to process the navigation information <NUM> of other ships sent from the management server <NUM> and the information acquired from the own user terminal <NUM> or the own ship, and to display the ships and other related information in the display form of the radar device.

The plot setting and display module <NUM> is configured to receive a selection of arbitrary position on the nautical chart from the user, and to store a useful information, an obstacle information, a fishing implement installation area information and the like.

The route plan setting module <NUM> is configured to accept an input of ship navigation plan from the user. By setting the destination and the transit point on the nautical chart, the route to the destination, the distance thereof, the required time thereof and the like are displayed. It is also possible to perform a navigation according to the inputted information.

It is possible to configure the plot setting and display module <NUM> and the route plan setting module <NUM> as a part of the map display module <NUM> and the radar display module <NUM>. In this case, it may be possible to consider that the processing performed by the plot setting and display module <NUM> and the route plan setting module <NUM> is a processing performed by the map display module <NUM> and the radar display module <NUM>.

The weather information display module <NUM> is configured to display the weather information obtained from the Meteorological Agency and other meteorological organizations sent from the management server <NUM>.

The radio module <NUM> is configured to provide the virtual radio function. The voice information inputted to the user terminal <NUM> is packetized, and then transmitted and received by the data communication such as the mobile telephone network or the like. As a result, a call function is realized as if with a VHF radio device.

When a ship in which the user terminal <NUM> having the ship navigational system <NUM> is used proceeds on a route where there is a possibility to collide with other ships or the like, the collision judgement module <NUM> displays an alert notification of warning or caution instructed by the management server <NUM> on the screen. It is possible to perform the calculation of the possibility of collision by the collision judgement module of the user terminal <NUM> instead of the management server <NUM>.

The GPS <NUM> is configured to acquire the position information of the user terminal <NUM> and temporarily store it in the user terminal navigation information <NUM>. Also, the GPS <NUM> has an electronic compass therein so that it is possible to obtain the orientation. The user terminal navigation information <NUM> is periodically transmitted to the management server <NUM> so that the position information of the user terminal <NUM>, that is, the position information of the ship on which the user terminal <NUM> is used, is transmitted to the management server <NUM>.

The input device <NUM> includes a touch panel, an audio input, an input by motion detection based on captured images of the camera unit <NUM> or the like. Also, it is possible to configure the input device <NUM> as an external input device such as a keyboard, a mouse or a microphone. These input devices may be operated by using the radio communication (wireless system) such as Bluetooth (registered trademark) or the wired communication.

The output device <NUM> is configured as a display of a smartphone or tablet. However, it is possible to configure it as a device or terminal for transmitting the information to an external monitor, a display, a printer, a device or the like and for displaying the transmitted information thereon.

The camera unit <NUM> captures on-site photographs so as to be registered in the plot information, or captures photographs at the time of the user registration or the ship registration.

The auxiliary storage device <NUM> stores the user terminal navigation information management DB <NUM>, and stores the position information of the user terminal <NUM> acquired from the GPS <NUM> of the user terminal <NUM> as the user terminal navigation management information <NUM>. It is possible to store the information obtained from the radar, the GPS plotter, the AIS, the wind direction and anemometer, the international VHF radio or the like disposed on the ship combined with the above-mentioned information.

The various modules are configured to analyze and process the various types of information stored in the auxiliary storage device <NUM> so as to calculate the position, the navigation state and the like of the ship, and output and display them on the respective terminals and output devices.

<FIG> illustrates an example of hardware configuration of the land-based management terminal <NUM>.

The land-based management terminal <NUM> is configured, for example, by using a desktop computer or a laptop computer.

The main storage device <NUM> stores programs and applications such as the management server cooperation module <NUM> and the work management module <NUM> and the like therein. When the processor <NUM> executes these programs and applications, the functional elements of the land-based management terminal <NUM> may be realized.

The management server cooperation module <NUM> is configured to log in to the management server <NUM>, to process the navigation information <NUM> of the ship, the plot management information <NUM>, the route management information <NUM>, the weather management information <NUM> and the like sent from the management server <NUM>, and to display the results on the screen.

In addition, it is possible to access to the management server <NUM> simply via a Web browser and to cooperate with the management server <NUM> so as to transmit, receive and display the information by using the functions of the Web browser, rather than the form of the application. The management server cooperation module <NUM> may be a Web browser itself, a script executable by the Web browser, or another application independent of the Web browser.

The work management module <NUM> may be an application which is used in the business of a shipping company that owns small ships or commercial ships, or of a land-based company such as a construction company, a leisure company or the like.

In addition, it is possible to access to a system in the cloud simply via a Web browser and cooperate therewith so as to transmit, receive, and display the information by using the functions of the Web browser, rather than the form of the application.

The ship navigational system <NUM> may cooperate with the work management module <NUM> of a land-based company.

The auxiliary storage device <NUM> stores a business management DB <NUM> for storing the work management information <NUM> therein.

<FIG> illustrates an example of the user management information <NUM> of the master information management DB <NUM>.

The user management information <NUM> is a master information for managing the user of the ship navigational system <NUM>.

A user profile ID <NUM>, a photograph ID <NUM>, a name (in native language) <NUM>, a name (in English) <NUM>, a telephone number <NUM>, an E-mail address <NUM>, an E-mail arrival confirmation <NUM>, a created date and time <NUM>, and an updated date and time <NUM> are stored therein, and therefore the data which can be used for specifying the user uniquely is stored therein.

When the ship is actually operated, the license information for the ship is also registered in association with the user profile ID <NUM>. For a small ship license, an information such as a license number, a name, a date of birth, a registered domicile, an address, a type of license, an expiry date of license, a date of issuance of license, a date of registration of license, a photograph of license and the like are registered.

For a large-scale ship license, an information such as a license classification, a license number, a date of license, a name, a sex, a date of birth, an address, a registered domicile or nationality, a date of issuance of license, an expiration date of license, a photograph of license and the like are registered.

<FIG> illustrates an example of the ship management information <NUM> of the master information management DB <NUM>.

The ship management information <NUM> is a master information for managing a ship which is required to be managed by the user of the ship navigational system <NUM>.

The information includes a ship ID <NUM>, a ship type ID <NUM>, a ship type ID <NUM> of a ship specification, a ship's name (in native language) <NUM>, a ship's name (in English) <NUM>, a ship's name in Kana (in <CIT>, a registry of the ship <NUM>, a ship port ID <NUM>, a ship number <NUM>, a ship ID number <NUM>, a status <NUM>, a ship IMO <NUM>, a ship MMSI <NUM>, a call sign <NUM>, a ship size ID <NUM>, a created date and time <NUM>, and an updated date and time <NUM>, and an information for uniquely identifying the ship is stored.

As for the type of ship, it is possible to register a tanker ship, a cargo ship, a tugboat, a passenger ship, a fishing ship, an enterprise ship, an application ship, a jet ski or the like.

The status indicates the current condition of the ship, and there may be "<NUM>: in port", "<NUM>: under operating" and "<NUM>: under maintenance".

<FIG> are examples of display screens <NUM> that are to be outputted to an output device of the user terminal <NUM>.

<FIG> illustrates an example of a map display screen <NUM> to be displayed on an output device of the user terminal <NUM>.

Various types of information are arranged and displayed on the nautical chart. The part having a dark color indicates an area of sea <NUM> and the part having a bright color indicates an area of land <NUM>. The map display module <NUM> is configured to display a nautical chart information <NUM>, <NUM> stored in the user terminal <NUM>, a menu panel <NUM>, an azimuth and speed meter <NUM>, a display section for name of operating ship <NUM>, a radio button <NUM>, a current position button <NUM>, a search button <NUM>, a display section for the current position <NUM> and the like based on the information stored in the application of the user terminal <NUM> in advance. The location information such as the ships <NUM>, <NUM> and other icons <NUM>, <NUM> and their contents and the navigation information <NUM> are sequentially received from the management server <NUM>, processed by the map display module <NUM>, and displayed on the nautical chart superimposingly as icons or the like.

Note that all of the information may be implemented by a client-side application in which the information is processed and displayed by the user terminal <NUM> based on the information stored in the user terminal <NUM>. Conversely, all of the information may be implemented by a server-side application in which the information is processed by the management server <NUM> and the user terminal <NUM> is simply configured to display the information received from the management server <NUM>.

The menu panel <NUM> is configured to display a plot information display button <NUM>, a route plan display button <NUM>, a weather information display button <NUM>, and a radar mode display button <NUM>. This menu panel <NUM> is mostly displayed on the screen even if the screen is changed among several forms. By tapping these buttons, the screen may be changed among the display of the plot information, the display of the route plan, the display of the weather information, and the display of the radar mode.

The azimuth and speed meter <NUM> displays the traveling azimuth angle (moving direction) and moving speed of the ship on which the user terminal <NUM> is disposed. The moving direction and the moving speed are calculated and displayed based on the temporal transition of the position information acquired by the GPS <NUM> which is mounted on the user terminal <NUM>. In addition, it is possible to display values taken from the external GPS, the compass, or the speedometer.

The display section for name of operating ship <NUM> is an area for displaying the name of the own ship, which is the operation target registered by the user.

The radio button <NUM> indicates a reception of virtual radio. When the virtual radio is received, the light is turned on in orange color. If this button is tapped, it is changed to the virtual radio function.

If the current position button <NUM> is tapped, a current position <NUM> is displayed on the nautical chart.

If the search button <NUM> is tapped, it becomes possible to display a search screen for searching the ship.

The display section for the number-of-ships <NUM> displays the number of ships displayed in the screen and the total number of received data in the form of the number of ships displayed in the screen or the total number of received data.

The display section for the rent radio location <NUM> displays the location of the radio devices that are rent. The green colored icon is displayed if the radio is turned on, and the red colored icon is displayed if the radio is turned off.

The display section for the location of a rental company <NUM> displays the location of the company that rents the radio.

The display section for the current position <NUM> indicates the position of the own ship.

The scale <NUM> displays the scale of the nautical chart. It is possible to enlarge or reduce the size of the nautical chart.

The obstacle <NUM> is an icon for indicating an obstacle on the sea.

According to the ship navigational system <NUM>, it is possible to display the information of the user terminal-equipped ships and the AIS-equipped ships together on the nautical chart.

The ships <NUM>, <NUM> are icons for displaying the positions of the ships equipped with the user terminal <NUM> at sea. The location information or the like acquired by the GPS <NUM> of the user terminal <NUM> disposed on each ship is stored in the management server <NUM> as the user terminal navigation information <NUM>. The information is processed and transmitted from the management server <NUM> to the user terminal <NUM> as the processed navigation information <NUM> including the ship type information and the ship position information of each ship. In a case where the user terminal <NUM> receives the navigation information <NUM>, the user terminal <NUM> displays the icon corresponding to the ship type of each ship at the ship position designated by the position information of each ship.

The AIS-equipped ships <NUM> are displayed as icons which indicate positions of relatively large ships such as an international ship, a passenger ship or other large ship or vessel equipped with the AIS device. The AIS information including the position information and the like transmitted from the AIS device of each ship via the VHF radio is acquired via the AIS system. The information is accumulated in the management server <NUM> as the AIS information <NUM> and the AIS information is processed and then transmitted from the management server <NUM> to the user terminal <NUM> as the processed navigation information <NUM> including the ship type information and the position information of each ship. In a case where the user terminal <NUM> receives the navigation information <NUM>, the user terminal <NUM> displays the icon corresponding to the ship type of each AIS-equipped ship at a position designated by the position information of each AIS-equipped ship. In this case, it is possible to display the icons having corresponding longitudinal and lateral sizes of the ships on the nautical chart based on the information of the length and width of the hull (body) of the ship.

It is possible to select the ship type and display the ship based on the selection. For example, it is possible to select the ship type from a tanker ship, a cargo ship, a tugboat, a passenger ship, a fishing ship, an own ship, an application ship, a water motorcycle and the like. It is also possible to select displaying or hiding the ships on the screen.

For the ship which proceeds at a predetermined speed or more (e.g., <NUM> knots or more) (cf. <NUM>, <NUM>, etc.), it is possible to light up the starboard light (in green color) and the port light (in red color). For a stopped ship (or a ship in port) or a ship moving at low speed (e.g., slower than <NUM> knots) (cf. <NUM>, etc.), it is possible not to light up the starboard light and the port light.

According to the display system of the conventional AIS system <NUM>, there is a case that the velocity vector of the ship is displayed at all times. In a case that the speed vector is long, it is possible to understand that the ship is moving. On the other hand, in a case that the speed vector is not displayed, it is possible to understand that the ship is stopped. However, in a case that all of the speed vectors are displayed for all ships on a smartphone or tablet having a small screen as in the ship navigational system <NUM>, the user interface thereof tends to become very difficult to understand on the small screen.

Therefore, according to the ship navigational system <NUM>, the predicted moving routes or the tracks for all ships are not always displayed on the basic screen. Only a specific ship is selected by tapping or the like, the predicted moving routes or the tracks thereof are allowed to be displayed. For other ships, the starboard side light and/or the port side light may be lighted up to indicate that the other ships are moving not without displaying the predicted moving routes.

When the ship <NUM> displayed on the screen is selected by tapping or the like, it becomes possible to display the ship information <NUM> such as the name of the ship, the speed of the ship, the distance from the own ship, the past track <NUM> of the ship, and the predicted moving route <NUM> of the ship to the predicted arriving position after a predetermined time (e.g., five minutes) in near future.

According to the conventional AIS display system, the velocity vector is displayed as a straight line based on the moving speed and the moving direction of the ship (course over the ground or heading) of the ship. In reality, however, the ships do not proceed on a straight line due to the influence of winds and waves.

According to the ship navigational system <NUM> of the present embodiment, in order to calculate a more accurate predicted moving route, the map display module <NUM> of the management server <NUM> is configured to calculate a predicted arriving position and a predicted moving route in near future after a predetermined period of time by using not only the moving speed and the course information of a certain point but also the navigation information <NUM> accumulated in past, and by using the moving route information of the ship from past to present.

For example, it is possible to calculate the predicted arriving position and the predicted moving route after <NUM> minutes based on the navigation information <NUM> up to <NUM> minutes before. Position information for five points of every minute from the present to five minutes before are acquired. Then an approximate quadratic curve of these points is obtained as a future predicted moving route based on the coordinates of five points by using the latitudes as the Y-axis and the longitudes as the X-axis. In addition, it is possible to calculate the predicted arriving position after <NUM> minutes by obtaining the predicted moving distance after <NUM> minutes based on the speed information or the moving distance information and by adjusting it to the predicted moving route.

According to the above-mentioned example, the calculation is made based on the position information. It is also possible to calculate a future velocity vector by using changes of velocity vector from <NUM> minutes before until the present so as to obtain a predicted arriving position and a predicted moving route after <NUM> minutes.

By calculating the deviation between the heading direction obtained from the electronic compass of the GPS <NUM> in the user terminal <NUM> and the heading direction in the moving direction determined from the navigation route of the last few minutes, it is possible to detect the turn (Rate of turn) and to calculate the head-turning rate. It is also possible to calculate the predicted moving route based on the moving direction (azimuth velocity vector) and the calculated head-turning rate.

Note that it is possible to display the predicted moving route more accurately by using a curved line based on the calculation as described above. However, it is also possible to display the speed vector linearly based on the moving speed and the course (course over the ground or heading) of the ship in the ship navigational system <NUM> of the present embodiment.

<FIG> illustrates an example of a ship information display screen <NUM>.

When the selected ship <NUM> or the ship information <NUM> displayed on the screen is further selected by tapping or the like, the map display module <NUM> displays the ship information display screen <NUM> for the selected ship.

The image of the ship uploaded by the user or the ship management company is displayed in the ship image <NUM>.

The detailed information <NUM> on the ship displays the management information of the ship stored in the ship management information <NUM> of the management server <NUM>, and the navigation information such as the speed and the course at the present time and at a predetermined time based on the navigation information <NUM>.

<FIG> illustrates examples of the voyage recording screens <NUM> and <NUM>.

The map display module <NUM> of the user terminal <NUM> is configured to display the navigation (voyage) record list <NUM> by acquiring the navigation record information <NUM> illustrated in <FIG> which is stored in the user terminal navigation information <NUM>, from the management server <NUM>. In the navigation record list <NUM>, the date and time <NUM> of the voyage, the distance of voyage <NUM>, and the operating time <NUM> of the past voyage information <NUM> are displayed. When the selection of one of these items <NUM> is accepted, the navigation record information <NUM> is displayed by acquiring the ship position information <NUM> illustrated in <FIG> which is stored in the user terminal navigation information <NUM>, from the management server <NUM>.

The route <NUM> of the selected ship <NUM> is displayed in the voyage record information <NUM>. It is possible to display the position of the ship at a predetermined time <NUM> by operating the slider bar (seek bar) <NUM>.

<FIG> illustrates examples of route plan setting and display screens <NUM> and <NUM>.

When the route plan display button <NUM> is tapped, the route plan setting module <NUM> of the user terminal <NUM> displays the nautical chart information stored in the user terminal <NUM>, a measurement menu display button <NUM>, a back button <NUM>, a forward button <NUM>, a line deletion button <NUM>, and the like based on the information stored in the application of the user terminal <NUM> in advance. Ships and other icons are displayed as icons and the like layered on the nautical chart as with the map display module <NUM>.

The measurement menu display button <NUM> is configured to display a menu for selecting an item to be displayed at the point <NUM> or <NUM> as a route plan or for inputting a speed setting at the time of the measurement.

It is possible to add a point to be routed by tapping a predetermined position on the nautical chart by the user. In this example, it is illustrated that a starting point <NUM> is selected, and then a first point <NUM> and a second point <NUM> are selected.

In a case that the point selection fails, it is possible to return to a former state by tapping the back button <NUM>. Also, it is possible to proceed to a previous state (next state) by tapping the forward button <NUM>. Furthermore, it is possible to delete the selected route to refresh it by tapping the line deletion button <NUM>.

In the distance display screen <NUM>, it is possible to display the point information <NUM>, <NUM> at each point. For example, the distances from the starting point <NUM> to each of the points <NUM> and <NUM> are displayed in the point information <NUM> and <NUM>.

It is also possible to select other display contents by using a menu which is displayed after tapping of the measurement menu display button, and to display the information such as a distance between the points, a required time, a scheduled arrival date and time, a course, a latitude and a longitude on the point information <NUM> and <NUM> and the like.

The registered route plan is stored in the route management information <NUM> of the support information management DB <NUM> of the management server <NUM>. It is possible to store it in the navigation information management DB <NUM> of the user terminal <NUM> as well. It is also possible to use the route plans as a navigating <NUM>. At the own ship representation <NUM>, the current position on the route is displayed. The time required from this current position to the next point <NUM> is displayed in the point information <NUM>. Also, the time required for the final destination <NUM> is displayed in the point information <NUM>.

The required time is calculated based on the speed setting (e.g., an initial value of <NUM> knots) and the distance at the measurement which are input by the menu. In the navigation mode, it is possible to recalculate it based on the current speed in the course of moving so as to display a more accurate time.

<FIG> illustrate an example of a general plot information display screen <NUM>.

The plot setting and display module <NUM> of the user terminal <NUM> acquires and processes the plot information stored in the plot management information <NUM> of the support information management DB <NUM> of the management server <NUM> so as to display the plot information <NUM>, <NUM> and the like on the nautical chart. The plot management information <NUM> stores a plot information <NUM>, a plot details information <NUM>, and a plot position information <NUM> as shown in <FIG>.

When the specific plot information <NUM> is selected by tapping or the like, the details <NUM> of the plot information are displayed.

<FIG> illustrates examples of general plot information setting screens <NUM>, <NUM>, <NUM> and <NUM>.

When the user selects a predetermined position on the nautical chart by tapping or the like, the plot setting and display module <NUM> displays a category selection screen <NUM> for adding a plot information. It is possible to select a category information such as a useful information, an obstacle, a warning, a map problem, a fishing equipment installation area and the like. For example, in a case that the useful information <NUM> is selected, the plot selection and display module displays a subcategory selection screen <NUM>.

For example, when the user selects the leisure spot (area for leisure) <NUM>, the plot selection and display module displays the plot information input screen <NUM> so as to accept an input of information for the title <NUM>, the comment <NUM>, and the image <NUM>. In the image <NUM>, the captured images or the selected images are displayed by the capturing image1224 and the selecting image <NUM>.

Then, the preview screen <NUM> is displayed, and when the completion button <NUM> is tapped, the plot selection and display module sends the plot information and the selected location information to the management server <NUM>. The management server <NUM> stores the sent information together with the position information in the plot management information <NUM>.

<FIG> illustrates an example of a fishery plot information display screen <NUM>.

The plot setting and display module <NUM> of the user terminal <NUM> acquires and processes the plot information stored in the plot management information <NUM> of the support information management DB <NUM> of the management server <NUM> so as to display the plot information for fishery <NUM> and the like on the nautical chart. As a main difference from the general plot information, the above-mentioned plot is displayed as an area composed of a plurality of pieces of position information instead of one piece of position information.

When the plot information <NUM> is selected by tapping or the like, the details <NUM> of the plot information are displayed.

<FIG> illustrates examples of the fishery plot information setting screens <NUM> and <NUM>.

When a predetermined position on the nautical chart is selected by tapping or the like by the user, the plot setting and display module <NUM> displays a category selection screen <NUM> for adding a plot information as illustrated in <FIG>. When the fishing implement installation area <NUM> is selected, the plot selection and display module displays an input screen <NUM> for the fishing implement installation information so as to accept an input of information for the name of the fishing implement <NUM>, the contact information <NUM> such as the name of the installer and the contact information and the like, the installation period <NUM>, the comment <NUM>, and the image <NUM>.

Then, the preview screen <NUM> is displayed. If the completion button <NUM> is tapped, the plot selection and display module displays the installation area selection screen <NUM>.

<FIG> illustrates an example of the installation area selection screens <NUM>, <NUM>, <NUM> and <NUM> of the fishery plot information.

The area is set by tapping and dragging the nautical chart by the user <NUM> (screen <NUM>). The plot selection and display module <NUM> terminates the drawing if the start point and the end point of the line being drawn are connected to each other, and sets the area <NUM> surrounded by the line as a plot area (installation area) (screen <NUM>). By pressing on the line (long pressing), the anchor point <NUM> is displayed and it becomes possible to edit the area <NUM> (screen <NUM>). It is also possible to change the position on the nautical chart by dragging the anchor point <NUM>.

When the plot area is determined, the confirmation display <NUM> is displayed, and the setting of the fishery plot is finished (screen <NUM>). The plot selection and display module sends the plot information and the selected plot area information (a set of a plurality of pieces of position information) to the management server <NUM>. The management server <NUM> stores the sent information together with the position information in the plot management information <NUM>.

<FIG> illustrates examples of weather information display screens <NUM>, <NUM>, <NUM> and <NUM>.

By tapping the weather information display button <NUM>, the weather information display module <NUM> of the user terminal <NUM> displays the map and nautical chart information stored in the user terminal <NUM>, the menu display button <NUM>, the radio (wireless) button <NUM>, the current location button <NUM>, and the search button <NUM>, and also displays the weather management information <NUM> sent from the management server <NUM> layered on the map and nautical chart. It is possible to send the map and nautical chart information together with the above-mentioned information from the management server <NUM>. It is also possible to acquire the weather information from another weather server instead of the management server.

By tapping the menu button, it becomes possible to choose the display screen from among the wind information display <NUM>, the wave information display <NUM>, and the wind and wave information display <NUM>.

By tapping on the map or by searching the position, the wind information <NUM>, the wave information <NUM>, or the wind and wave information <NUM> at the point is displayed.

<FIG> illustrates an example of a radar mode display screen <NUM>.

In general, the radar equipment is configured to measure a distance to an object by emitting radio waves by itself and catching the reflected wave, and to display the object on the radar. According to the present embodiment, it is possible to provide a representation similar to that of the expensive radar equipment by using the user terminal.

In the radar mode display of the ship navigational system <NUM>, the radar display module <NUM> of the user terminal <NUM> draws icons of the ships and the like at positions of the ships, obstacles and the like on the radar mode display based on the navigation information <NUM> which is sent from the management server <NUM>.

The radar display module <NUM> is configured to display the own ship <NUM> at the center of the screen. In other words, when the ship moves, the position of the own ship <NUM> does not change (it is fixedly displayed), and the nautical chart will move in the opposite direction to the moving direction of the own ship.

The velocity vector <NUM> of the own ship indicates the moving speed of the own ship. The radar display module <NUM> displays the arrow by changing the length of the arrow corresponding to the changes of the moving speeds. The leading edge of the arrow indicates the predicted arriving position of the own ship after a predetermined period of time (e.g., <NUM> minutes).

The moving direction <NUM> indicates the moving direction of the own ship by a straight line.

The concentric circles <NUM> around the own ship indicate the distance from the own ship and the distances between the adjacent concentric circles is displayed in the interval section <NUM>. Also, the scale of the nautical chart is displayed in the scale section <NUM>.

The radio button <NUM> indicates a receiving condition of the virtual radio. When the virtual radio is received, the light is turned on in orange color, and when this button is tapped, the screen is changed to the virtual radio function mode.

The radar display module <NUM> is configured to display icons <NUM> and <NUM> of the other ships at the positions based on the navigation information <NUM> of the other ships received from the management server <NUM>.

The radar display module <NUM> is configured to calculate and display the predicted arriving positions and the predicted moving routes <NUM> after a predetermined time (e.g., five minutes) of the other ships when the other ships enter within an area encircled by the outer circle. It is possible to explain that this calculation is performed by the radar display module <NUM> of the user terminal <NUM>. However, it is also possible to perform the calculation by the radar display module <NUM> of the management server <NUM> so as to transmit the position information and the curve information to the user terminal <NUM>. Then, the user terminal <NUM> may draw the information on the screen.

It is possible to display not only the user terminal-equipped ships <NUM> and <NUM> but also the information about the AIS device-equipped ships <NUM> and <NUM> in the radar display screen <NUM> similar to the map display screen <NUM>.

<FIG> illustrates examples of caution and warning display screens <NUM> and <NUM> in the radar mode.

The caution screen <NUM> and the warning screen <NUM> are displayed according to the approaching condition of the other ships.

The radar display module <NUM> is configured to display a notification of caution <NUM> in yellow when it is determined that the predicted moving route <NUM> of the other ship <NUM> and the moving direction <NUM> of the own ship <NUM> cross with each other. Velocity vector <NUM> of the other ship <NUM> and the other ship are displayed by changing the color to yellow. The speed vector <NUM> of the own ship <NUM> is also displayed by changing the color to yellow.

The radar display module <NUM> is configured to calculate the time <NUM> until the predicted moving route <NUM> of the other ships and the moving direction <NUM> of the own ship cross with each other, and to display the predicted arriving position <NUM> of the own ship on the speed vector <NUM> at the time to be displayed.

Furthermore, the radar display module <NUM> is configured to display a notification of warning <NUM> in red when it is determined that the predicted moving route <NUM> of the other ship <NUM> and the moving direction of the own ship cross with each other within three minutes. In this case, the velocity vector <NUM> of the other ship <NUM> and the other ship are displayed by changing the color to red. In addition, a warning <NUM> by using an animation of red colored concentric circles is displayed around the other ship <NUM>. Also, the velocity vector <NUM> of the own ship is displayed by changing the color to red.

The radar display module <NUM> is configured to calculate a time <NUM> until the predicted moving route <NUM> of the other ship <NUM> and the moving direction of the own ship cross with each other, and displays the predicted arriving position <NUM> of the own ship on the speed vector <NUM> at the time to be displayed.

By tapping the ship icons <NUM> and <NUM>, the detailed information of the ships are displayed in the same manner as described in the map display, and the name, the speed, the distance from the own ship, the speed vector, the track and the like are displayed.

<FIG> illustrate a method for judging the caution and warning in accordance with the claimed subject matter.

<FIG> illustrates a diagram for explaining a determination area of caution/warning.

It is used to determine whether there is a possibility of collision between the own ship and the other ship (or between other ships).

The warning area <NUM> is illustrated as a fan-shaped area having a radius <NUM> and a center angle <NUM>. Also, the caution area <NUM> is illustrated as a fan-shaped area having a radius <NUM> and a center angle <NUM>.

The warning area <NUM>, illustrated in a dark color, is an area which is determined based on a potential area of outsailing ships according to the Prevention of Collision at Sea Act. The arrow <NUM> is directed in the moving direction, and the tip of the arrow <NUM> indicates, for example, the predicted arriving position after <NUM> minutes, and the length of the arrow <NUM> indicates the moving distance from the current position to the predicted arriving position after <NUM> minutes. The center angle <NUM> is based on the angle of the outsailing ship and it is an angle of <NUM> degrees from just beside of the ship to its back. That is, the center angle is <NUM> degrees with angles of <NUM> degrees to the left and right from the moving direction.

Therefore, the warning area <NUM> is a fan-shaped area having angles of <NUM> degrees to the left and right from the predicted straight-line arrival distance after <NUM> minutes.

The caution area <NUM>, illustrated in light color, is an area which is determined based on a potential area of ships passing each other according to the Prevention of Collision at Sea Act. The arrow <NUM> is directed in the moving direction of the ship, the tip of the arrow <NUM> indicates, for example, the predicted arriving position after <NUM> minutes, and the length of the arrow <NUM> indicates the moving distance from the current position to the predicted arriving position after <NUM> minutes. The center angle <NUM> is effective if it is a range of about <NUM> to <NUM> degrees based on past marine accident trial cases. In this system, each angle is selected as <NUM> degrees to the left and right from the moving direction.

Therefore, the caution area <NUM> is selected as a fan-shaped area having the angle of <NUM> degrees to the right and left from the predicted straight line arrival distance after <NUM> minutes.

In a case that the caution area <NUM> and the warning area <NUM> overlap with each other, the warning area takes priority over the caution area for the overlapped area (area having a radius <NUM> and a center angle <NUM>), and the area is considered to be the warning area.

It is clear that the predicted arrival distance <NUM> of the caution area <NUM> is longer than the predicted arrival distance <NUM> of the warning area <NUM>, and the center angle <NUM> of the caution area <NUM> is narrower than the center angle <NUM> of the warning area <NUM>.

According to the ship navigational system <NUM>, the notification of caution or the notification of warning is displayed depending on whether the caution area <NUM> and the warning area <NUM> of the ships overlap with each other or not.

In this example, the azimuth speed vector is used for the actual moving direction of the ship for the moving direction of the arrows <NUM> and <NUM>. However, it is possible to use a bow direction vector as the direction of the bow instead. Also, it is possible to set the fan-shape of the caution area to have <NUM> degrees to the left and right from the azimuth velocity vector of the ship, and to set the arrow <NUM> to be the bow direction vector. In this case, the caution area indicates a possible area of the actual progress of the ship based on the estimation obtained from the past movement from the GPS or the like, while the direction in which the ship is currently facing is represented by the arrow <NUM>. Similarly, for the warning area, the representation of the warning area may be displayed by using the azimuth velocity vector, and the arrow <NUM> may be displayed by using the bow direction vector.

Also, in the radar mode illustrated in <FIG> or in the map mode illustrated in <FIG>, it is possible to display the caution area and the warning area as illustrated in <FIG>.

It should be noted that although the narrow fan-shape <NUM> is used as the caution area and the wide fan-shape <NUM> is used as the warning area, conversely, the narrow fan-shape <NUM> may be used as the warning area and the wide fan-shape <NUM> may be used as the caution area.

<FIG> illustrates diagrams for explaining the determination of the notification of caution/warning.

Note that the importance level and the emergency level of the notification of warning are higher than those of the notification of caution.

For example, the notification of caution is displayed in a conspicuous color such as yellow in an area <NUM> of <FIG>. On the other hand, the notification of warning is displayed in a conspicuous color such as red in an area <NUM> in <FIG>.

In addition, it is also possible not to display the notifications of caution and warning in a certain case where the possibility of collision is determined as low based on the determination of overlapping of the areas as illustrated in <FIG>. For example, when two ships are proceeding in the same direction (the rightmost case of (C)), the notifications of caution and warning are not displayed even if these areas overlap with each other. Also, the notifications of caution and warning are not displayed in a case where the speed of the preceding ship is higher than that of the following ship and the both of them proceed in the same direction. The alteration is possible. For example, the notifications of caution and warning may not be displayed in a case that the forward ship is stopped (at a port or the like). Even if the notifications of caution and warning are not displayed in this way, it is possible to display only the information of the other ship entering the caution/warning area. Also, it is possible to display the caution area or warning area in which the other ship entering on the nautical chart. Also, it is possible to change the color of the other ship in these cases. The alteration is possible.

Suppose that the warning area has the narrow fan-shape <NUM> and the caution area has the wide fan-shape <NUM>, then in the case of (a), the notification of warning is displayed because the warning areas overlap with each other. Also, in the case of (b), the notification of caution is displayed because the warning area and the caution area overlap with each other. Furthermore, in the case of (c), the notification of caution is displayed because the caution areas overlap with each other.

<FIG> illustrates diagrams for explaining the determination of the notification of caution/warning for a ship at a stop.

<FIG> illustrates a diagram for explaining the determination of caution and warning for a plot area such as a construction area and the like.

In a case that a construction area <NUM> is set as a plot area by similar processings as the fishery plot, the radar display module <NUM> and the map display module <NUM> are able to estimate the plot area of the construction area by acquiring the plot management information <NUM> from the management server <NUM>. The radar display module <NUM> and the map display module <NUM> display the notification of caution for the ship <NUM> which is trying to enter in the area and the warning ships <NUM> and <NUM> which are warning of the area when the caution area <NUM> of the ship overlaps within the construction area <NUM>. For example, as for the area <NUM> of <FIG>, it is possible to display a prominent color such as yellow with a message of "It is going to enter the construction area after <NUM>:<NUM>".

In a case that the warning area <NUM> of the ship overlaps within the construction area <NUM>, the notification of warning is displayed to the ship <NUM> which is trying to enter in the area and the warning ship <NUM> or <NUM> which are warning of the area. For example, as for the area <NUM> in <FIG>, it is possible to display a prominent color such as red with a message of "It is going to enter the construction area after <NUM>:<NUM>".

It is also possible to display the notifications of caution and warning not only to the warning ships <NUM> and <NUM> and the own ships <NUM> and <NUM>, but also to the ship <NUM> which is within a predetermined area (e.g., <NUM> or less) from the construction area.

According to the ship navigational system <NUM>, it is possible to display both of the user terminal-equipped ships and the AIS device-equipped ships together on the map display and the radar mode display. Also, it is possible to perform the collision determination by acquiring the AIS information <NUM> and the user terminal navigation information <NUM> for both of the ships equipped with the user terminal without the AIS and the ships equipped with the AIS so as to display the notifications of caution and warning to the user terminal.

Furthermore, it is possible to send the message and the notifications of caution and warning and display on the AIS by cooperating with the AIS system <NUM> to the AIS device-equipped ships by using the VHS radio.

<FIG> illustrate examples of display screens to be output on the output device of the land-based management terminal <NUM> or the like.

The outputting the screens may be implemented by the client-side processing which performs most of the processing on the client side. Conversely, it may be implemented by the server-side processing which performs most of the processing on the server side and the land-based management terminal <NUM> is simply configured to receives and displays the images.

<FIG> illustrates an example of a map display screen <NUM> to be displayed on the output device of the land-based management terminal <NUM>.

The management server cooperation module <NUM> of the land-based management terminal <NUM> displays respective ships on the nautical chart. Usually, the land management terminal <NUM> is used by a certain land-based company so as to manage the information of a plurality of ships which are managed by the land-based company collectively.

In the ship list <NUM>, a list of ships which are currently managed by the land-based company is displayed. When one of the ships is selected, the information of the selected ship disappears from the list and a detailed information is displayed in the ship detail display area <NUM> on the right side of the screen instead. The image <NUM> of the ship and the detailed information <NUM> are displayed in the ship detail display area <NUM>. The information may be acquired from the ship management information <NUM> and the navigation information <NUM> of the management server <NUM> and displayed on the screen.

The selected ship <NUM>, the past track <NUM> of the ship, and the predicted moving route <NUM> to the predicted arriving position after a predetermined time in future (for example, five minutes) are displayed on the nautical chart.

<FIG> illustrates an example of a navigation record screen <NUM>.

The management server cooperation module <NUM> of the land-based management terminal <NUM> is configured to display the voyage record information of each ship on the voyage nautical chart of the ship displayed in the ship list <NUM>.

When the selection of one of the ships in the ship list <NUM> is accepted, the past track of the selected ship <NUM> is displayed. It is possible to display the position of the ship at a predetermined time by operating the slider bar <NUM>. Also, it is possible to play back the navigation record information at double speed, quadruple speed, eighth speed or the like by operating the playback button <NUM>.

<FIG> illustrates an example of a route plan setting and display screen <NUM>.

It is possible to set the route plan at the land-based management terminal <NUM> similarly to the case of the user terminal <NUM>.

When the display content is selected from the measurement tool menu <NUM>, the management server cooperation module <NUM> displays the information <NUM> corresponding to the points of the respective routes <NUM> and <NUM>. For example, in the example of the screen <NUM>, distances from the starting point to each point are displayed.

In the case of the land-based management terminal <NUM>, it is possible to increase a management efficiency and a productivity by setting and managing the routes of a plurality of ships which are managed by the land-based company.

<FIG> illustrates examples of the general plot information display screens <NUM> and <NUM>.

A plurality of plots <NUM> and <NUM> are displayed. When one of them is selected, the detailed information <NUM> is displayed, and it becomes possible to set and edit the information.

Similar to the user terminal <NUM>, it is possible to register a new plot information. For the case of the land-based management terminal <NUM>, it is possible to increase the management efficiency and productivity by plotting and managing the information of a plurality of works and the like which are managed by the land-based company.

<FIG> illustrates examples of fishery plot information display screens <NUM> and <NUM>.

Similar to the user terminal <NUM>, it is possible to register a new plot area information <NUM>, and set and edit the detailed information <NUM>. For the case of the land-based management terminal <NUM>, it is possible to increase the management efficiency and productivity by plotting and managing a plurality of fishing implement installation information and the like which are managed by the land-based company.

<FIG> illustrates examples of the user terminal navigation information <NUM>.

The management server <NUM> integrates the user terminal navigation information <NUM> transmitted from a plurality of user terminals <NUM> and stores them in the user terminal navigation information <NUM> of the management server <NUM>.

The user terminal navigation information <NUM> includes a navigation record information <NUM> and a ship position information <NUM>.

The navigation record information records a history of the navigations of the ships registered in the user terminal <NUM>. A navigation record ID <NUM>, a user ID <NUM>, a ship ID <NUM>, a corporate ID <NUM>, a project ID <NUM>, a status <NUM>, a starting time of operating a ship <NUM>, an ending time of operating a ship <NUM>, a purpose of operating a ship <NUM>, a total operating distance <NUM>, a maximum operating speed <NUM>, a created date and time <NUM>, an updated date and time <NUM> and the like are stored in the navigation record information.

In the operation history ID2801, unique IDs are automatically assigned to each of the navigation records, and the IDs become a key information to be referred from the ship position information <NUM>. The user ID <NUM> is an ID allocated to each user terminal <NUM> and corresponds to an information for identifying the user terminal <NUM>. It refers to the user profile ID <NUM> of the user management information <NUM>. The ship ID <NUM> is an ID for specifying a ship on which the user terminal <NUM> is used. It refers to the ship ID <NUM> of the ship management information <NUM>. The status <NUM> may indicate that "<NUM> : in port", "<NUM>: under operating", and "<NUM> : under maintenance".

The ship position information <NUM> stores the moving track in each navigation record at every second, and stores a ship position ID <NUM>, a ship operation history ID <NUM>, a latitude <NUM>, a longitude <NUM>, a direction <NUM>, a distance (meter) <NUM>, a speed (kilometer per hour) <NUM>, a created date and time <NUM>, an updated date and time <NUM> and the like. By transmitting the position information acquired by the GPS <NUM> of each user terminals <NUM> mounted on a plurality of ships to the management server <NUM> by using the respective user terminals <NUM>, it becomes possible to store the ship position information <NUM> for each user terminal <NUM>.

The operating position ID <NUM> is the ID which is automatically issued in the sequence. The operation history ID <NUM> refers to the operation history ID <NUM> of the operation record information <NUM>, and specifies the corresponding ship position information from the operation record.

Each column is generated and stored so as to be specified by the created date and time <NUM> at every second, and store the latitude, the longitude, the direction of the ship, the moving distance from the previous stored point, and the speed at the point of time.

By acquiring the user terminal navigation information <NUM>, it becomes possible to confirm the time and the position of the ship in a chronological order.

According to the AIS information <NUM> used in the AIS system <NUM> utilizing the VHF radio, it is possible to acquire a position information, a world standard time information, a course to ground, a speed to ground, a heading direction, a navigational condition, and a head-turning rate as dynamic information. Also, it is possible to acquire an IMO number, a calling code and a ship's name, a length and a width of ship, a type of ship, and a position of positioning antenna as static information. Furthermore, it is possible to acquire an information on a draft of ship, a dangerous cargo (type), a destination, a scheduled arrival time, and an information for safety of navigation as navigational information. It is possible to store the AIS information <NUM> in the navigation information management DB <NUM> of the management server <NUM> and display on the screen.

By using the position information and the like of the AIS information <NUM>, it is possible to display the positions of ships relating to a large-sized ship and a large passenger ship on the nautical chart.

<FIG> illustrates examples of the plot management information <NUM>.

The plot management information <NUM> includes a plot information <NUM>, a plot details information <NUM>, and a plot position information <NUM>. The plot information <NUM> stores a basic information of a created plot, and includes a plot ID <NUM>, an account ID <NUM>, a plot category ID <NUM>, a title <NUM>, a plot type flag <NUM>, a plot detail ID <NUM>, a created date and time <NUM>, and an updated date and time <NUM>.

The plot ID <NUM> is a sequential ID which is generated automatically at each time a plot is created. The title <NUM> indicates a summary of the plot. The plot detail ID <NUM> refers to the plot detail ID <NUM> of the plot details information <NUM>.

The type of plot is registered in the plot category ID <NUM>. For example, as an upper-order category, it is possible to set a construction area, a restricted navigation area, a sign, a useful information, an obstacle, a caution, an urgent, a map problem, a fishing equipment installation area and the like. Also, as a lower-order category, it is possible to set a refueling station, a marina, a sign, a leisure spot and the like for the useful information. Similarly, it is possible to set a part, a floating object, a shallow, a net and the like for the obstacles. Also, it is possible to set a wave caution, a control boat, a construction area, a dangerous area and the like for the caution. Also, it is possible to set a rescue area, an accident and the like for the urgent.

The plot details information <NUM> stores a detailed information relating to the plot, and includes a plot details ID <NUM>, a photograph ID <NUM>, a business name <NUM>, a contact address <NUM>, a start date of work <NUM>, an end date of work <NUM>, a comment <NUM>, a created date and time <NUM>, and an updated date and time <NUM>. When the user registers the plot information, the details information is stored in the plot details information <NUM>. IDs for specifying photographs to be registered as plot information are stored in the photograph ID <NUM>. Comments registered by the user are stored in the comment <NUM>.

The plot position information <NUM> stores the position information of respective plots, and includes a plot point ID <NUM>, a plot ID <NUM>, a latitude <NUM>, a longitude <NUM>, an order <NUM>, a created date and time <NUM>, and an updated information <NUM>.

The plot point ID2941 is a sequential ID generated automatically at each plot position. The plot ID <NUM> refers to the plot ID <NUM> of plot information <NUM>. In a case that an area is registered as a plot area rather than a point, such as a fishery plot, an information indicating a plurality of plot positions will be generated for one plot ID <NUM>, and an area surrounded by a plurality of plot positions will become a plot area. The order <NUM> indicates the sequential order of the information indicating a plurality of plot positions for the plot area.

The user terminal <NUM> and the land-based management terminal <NUM> register the plot information by recording the information as the plot management information <NUM> at the time of plot setting. Thus, other users are able to display the plot information on the nautical chart by reading the information.

<FIG> illustrates an example of a flow <NUM> which is performed in the management server <NUM> for storing the navigation information <NUM>.

The navigation information storage module <NUM> of the management server <NUM> acquires the AIS information from the AIS system <NUM> (<NUM>).

The navigation information storage module <NUM> acquires the user terminal navigation information from a plurality of user terminals <NUM> (<NUM>).

The format of the AIS information and the format of the user terminal navigation information are different with each other. However, the navigation information storage module <NUM> is able to reformat them to the format of the navigation information <NUM> so as to be used in the user terminals such as the location information, the ship's name, the speed information, and the bow direction information and the like used in the map display or the radar mode display of the ship navigational system <NUM>. The formatted information is stored in the navigation information management DB <NUM>.

The navigation information storage module <NUM> continues to acquire the AIS information <NUM> as the navigation information <NUM> and the user terminal navigation information <NUM> always in real time.

In response to a request from the user terminal <NUM>, the map display module <NUM> reads the formatted navigation information <NUM> from the navigation information management DB <NUM> and transmits it to the user terminal <NUM>.

<FIG> illustrates an example of a flow <NUM> which is performed in the user terminal <NUM> for displaying the navigation information <NUM>.

The map display module <NUM> or the radar display module <NUM> of the user terminal <NUM> acquires the nautical chart information from the management server <NUM> or the external map server (<NUM>). It is possible to download and store the map and nautical chart information in the auxiliary storage device in advance so as to be read appropriately.

The map display module <NUM> or the radar display module <NUM> receives the formatted navigation information <NUM> from the management server <NUM> (<NUM>).

The icon of the corresponding ship is displayed at an appropriate position on the nautical chart which is indicated by the position information stored in the navigation information <NUM>. In addition, the navigation information <NUM> includes the position information acquired from a plurality of user terminals <NUM> by using the respective GPS <NUM>. Thus, it is possible to display the position information of a plurality of ships having the user terminals <NUM> by collectively managing the position information at the management server <NUM> side.

It is also possible to display the icon of the ship at the position of the AIS device-equipped ship because the AIS information <NUM> is also stored in the navigation information <NUM>. In this case, it is possible to clearly indicate that the ship is the AIS device-equipped ship by using an icon which is different from the icon of the ship on which the user terminal <NUM> is used.

It is also possible to display only the information of the AIS device-equipped ships. On the other hand, it is also possible to display only the information of the user terminal-equipped ships.

The map display module <NUM> or the radar display module <NUM> of the user terminal <NUM> is configured to map and draw a ship on the nautical chart. However, it is also possible to map the ship information by the map display module <NUM> or the radar display module <NUM> of the management server <NUM>, and transmit the mapped image information to the user terminal <NUM> and display it on the screen thereof.

<FIG> illustrates an example of a process flow <NUM> of displaying the caution/warning alert for a collision of <FIG>.

The collision judgement module <NUM> of the management server <NUM> calculates the predicted moving route <NUM> of the other ship and the predicted moving route of the own ship, and determines whether they cross with each other or not (<NUM>). The predicted moving route is, for example, a route to a predicted arriving position after <NUM> minutes.

In the case of crossing, the collision judgement module <NUM> calculates the time to the event of crossing (<NUM>). If the time to crossing is determined less than <NUM> minutes, the radar display module <NUM> is instructed to display a notification of warning, such as warning display <NUM>. The radar display module <NUM> displays the notification of warning <NUM>. The other ship <NUM> is displayed by changing the color to red. In addition, the warning <NUM> is displayed by using an animation of red colored concentric circles around the other ship <NUM>. The velocity vector <NUM> of the own ship is also displayed by changing the color to red.

Furthermore, the radar display module <NUM> displays the time <NUM> to the event of the crossing between the predicted moving route <NUM> of the other ship <NUM> and the moving direction <NUM> of the own ship, and displays the predicted arriving position <NUM> of the own ship at the time on the speed vector <NUM> (<NUM>).

In a case that the time to the crossing exceeds three minutes, the radar display module <NUM> is instructed to display the notification of caution, such as the caution display <NUM>. The radar display module <NUM> displays the notification of caution <NUM>. The other ship <NUM> is displayed by changing the color to yellow. Also, the velocity vector <NUM> of the own ship is displayed by changing the color to yellow.

The radar display module <NUM> calculates the time <NUM> until the predicted moving route <NUM> of the other ship and the moving direction <NUM> of the own ship cross with each other, and displays the predicted arriving position <NUM> of the own ship at the time on the speed vector <NUM>.

Until an instruction for terminating the display is received, the radar display module <NUM> and the collision judgement module <NUM> continue to execute the flow of processing the caution/warning alert (<NUM>). Once it is determined that the other ship and the own ship are separated and the predicted moving distance of the other ship and the predicted moving distance of the own ship do not cross with each other again, the displaying of the notification of caution/warning is reset and the flow is repeated (<NUM>).

<FIG> illustrates an example of another flow <NUM> of processing of the caution/warning for a collision of <FIG>.

The collision judgement module <NUM> of the management server <NUM> determines whether the caution or warning area of the own ship overlaps the caution or warning area of other ships (<NUM>) or not.

In a case that both of them overlap with each other, it is determined whether the warning area of the own ship overlaps the warning area of the other ship or not (<NUM>). If both of them overlap with each other, the notification of warning is displayed (<NUM>).

In a case that both of them do not overlap with each other, it is determined whether the caution area of the own ship overlaps the caution area of the other ship or not (<NUM>). If both of them overlap with each other, the notification of caution is displayed (<NUM>).

In a case that both of them do no overlap with each other, it means that the caution area of the own ship overlaps with the warning area of the other ship, or the warning area of the own ship overlaps with the caution area of the other ship. In this case, the notification of caution is displayed (<NUM>).

According to the above-mentioned flow, there are two types of notifications such as the notification of warning and the notification of caution. In this case, the level of importance or urgency of the notification of warning is higher than that of the notification of caution. Since the notifications are set in two levels, the notification of caution is displayed when the area of caution and the area of warning overlap with each other as in the step <NUM>, but the notification of warning may be displayed in such a case in consideration of safety.

It is possible to set the levels of the notification in the three levels instead of the two levels. For example, in a case that the area of caution and the area of warning overlap with each other as in the step <NUM>, a notification of the middle level of the three levels such as "serious caution" may be displayed.

Although the collision determination is performed by the collision judgement module <NUM>, in the actual display of the caution/warning, the notification of caution/warning is displayed by the user terminal <NUM> by giving an instruction to display to the map display module <NUM> or the radar display module <NUM> of the user terminal <NUM>.

Until an instruction for terminating the display is received, the collision judgement module <NUM> and the display module continue to execute the flow of processing the caution/warning (<NUM>). Once it is determined that the other ship and the own ship are separated and the caution/warning area of the other ship and that of the own ship do not overlap again, the displaying of the notification of caution/warning is reset and the flow is repeated (<NUM>).

According to the 2nd embodiment, details of a virtual radio system which is used in the ship navigational system <NUM> will be described.

<FIG> illustrates an example of a virtual radio function display screen <NUM>.

The virtual radio is configured by using a data communication of the mobile telephone network instead of the VHF radio, so as to communicate with an interface similar to the VHF radio device virtually. The virtual radio implements the function of the virtual VHF radio and the function of the group radio.

A radio button <NUM> indicates a receiving of the virtual radio. When the virtual VHF radio is received, the light is turned on in orange color. And when this button is tapped, it is changed to the virtual VHF radio function mode. An orange colored transmission icon <NUM> in the same series as the button is displayed on the ship which transmits the virtual VHF radio.

When the group radio is received, the wireless button <NUM> is turned on in green color. And when this button is tapped, it is changed to the group radio function mode. A green colored transmission icon <NUM> in the same series as the button is displayed on the ship which transmits the group radio.

<FIG> illustrates examples of virtual radio control panels <NUM>, <NUM>.

In the virtual VHF radio control panel <NUM>, the virtual VHF radio function and the group radio function are able to be switched by using the segment controls <NUM> and <NUM>.

When a channel is selected, the channel number <NUM> is changed in real time. The channel <NUM> is corresponding to the paging frequency. This channel is used to call the other station. Then, it is moved to the channel according to the type.

In an actual VHF radio, a different frequency is assigned to each channel, and the communication is performed by switching the frequency. On the other hand, in the case of the virtual VHF radio, the communication is performed by using the IP protocol or the like in the data communication of the mobile telephone network. For example, the channel number is assigned to each communication simulatively so that only the data to which the same channel number is assigned is able to be transmitted and received each other.

The receiving status display buttons <NUM> and <NUM> are displayed in green color in a blinking manner upon receiving data by radio. Also, the buttons <NUM> and <NUM> are displayed in red color in a blinking manner upon transmitting data.

The Hi/Low indications <NUM> and <NUM> are configured to label the status of Hi/Low of pseudo-radio intensity.

By tapping the PTT (Push to talk) buttons <NUM> and <NUM>, it becomes possible to speech. The buttons are displayed in red color during the transmission of data to make the transmission state easier to be understood.

In the group radio control panel <NUM>, the radio communication which is communicatable only between the set groups is realized by using the data communication of the mobile telephone network simulatively.

In the group name <NUM>, the name of the organization which uses the group radio is displayed. Only the group channel assigned to the group is allowed to be used. Since the communication is restricted in advance, the channel selection is not allowed (also, the button is not displayed).

In <FIG>, examples of virtual radio function display screens <NUM> performed in the land-based management terminal <NUM> or the like are illustrated.

In the green colored group radio transmitting and receiving area <NUM>, the current group setting status of the group radio is displayed. Also, the name of group radio which is fixed and currently in use is displayed.

In the orange colored virtual VHF transmitting and receiving area <NUM>, the channel information which is currently in use by the virtual VHF radio is displayed. Also, the channel numbers from <NUM> to <NUM> are displayed.

The transmitting and receiving indicator lamp <NUM> indicates a transmitting status and a receiving status. Upon receiving data, it is displayed in green color in a blinking manner. Also, it is displayed in red color in a blinking manner upon transmitting data. The radio is able to be transmitted while the channel is selected and the PTT (Push to talk) button <NUM> is pressed. During data transmission, the microphone icon <NUM> is blinked in red color.

A green colored balloon <NUM> is displayed for a ship which is transmitting the group radio (in talking mode), and an orange colored balloon <NUM> is displayed for a ship which is transmitting the virtual VHF (in talking mode).

By clicking a range button <NUM>, the icon is changed to blue color, and a radio transmitting and receiving area <NUM> is displayed on the map, and then the use of the Hi-Lo buttons <NUM>, <NUM> becomes enabled. By clicking the button again, the transmitting and receiving area is hidden and the use of the Hi/Lo button becomes disabled.

In the case of the VHF radio, there is a limit in the reach of the VHF radio waves so that the area where the radio wave can reach becomes the area where the radio communications is allowed eventually. By increasing or decreasing the wave strength (set to Hi or Lo), the area where the radio wave can reach is increased or decreased so that the area where radio communications can be performed is increased or decreased.

On the other hand, in the virtual radio function, the data communication by using the mobile telephone network reproduces the VHF radio interface simulatively. Since it is actually the communication using IP, it is possible to communicate anywhere as long as it is connected to the network. Therefore, in the case of the virtual radio function, the area in which the communication can be performed is limited to within an area of, for example, a radius of <NUM> from the center position of the corporation <NUM> which lends the radio.

By clicking the Hi button <NUM>, the radio module <NUM> expands the transmitting and receiving area <NUM> to within an area of, for example, a radius of <NUM>. Also, by clicking the Lo button <NUM>, the area is reduced to, for example, within an area of radius <NUM>.

Thus, it is possible to expand and reduce the transmitting and receiving area simulatively so that an interface like a VHF radio is created. Therefore, the conventional users of the VHS radio are able to use the interface without feeling uncomfortable.

In <FIG>, an example of a flow <NUM> of processing the virtual radio is illustrated.

The radio module <NUM> of the management server <NUM> acquires the position information of the company <NUM>, which rented the radio, from the radio management information <NUM> (<NUM>), and acquires the position information of the user terminal <NUM> which is included in the user terminal navigation information <NUM> (<NUM>).

The radio module <NUM> determines whether the Hi button <NUM> has been pressed or not (<NUM>) and, if pressed, it provides a radio function to the user terminal <NUM> which is located within an area of, for example, a radius of <NUM> from the company <NUM>(<NUM>).

The radio module <NUM> determines whether the Lo button <NUM> has been pressed or not (<NUM>) and, if pressed, it provides a radio function to the user terminal <NUM> which is located within an area of, for example, a radius of <NUM> from the company <NUM> (<NUM>).

When none of the buttons is pressed, it provides the radio function to the user terminal <NUM> which is located within a normal area of, for example, a radius of <NUM> from the company <NUM> (<NUM>).

The radio module <NUM> continues to acquire the position information of the user terminal <NUM> and repeats the flow until it receives an instruction to terminate the radio function or to terminate the map display or the radar mode display (<NUM>).

The present invention is not limited to the above-described embodiments, and various modifications can be included. For example, the above-described examples have been explained in detail for the purpose of illustrating the present invention easily. The present invention is not necessarily limited to these examples which include all of the described configurations.

In addition, some or all of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware, for example, by using an integrated circuit. In addition, the above-described configurations, functions, and the like may be implemented by software with which a program is interpreted and executed by the processor so as to realize the respective functions. Information such as programs, tables, and files that realize various functions can be stored in a memory, a recording device such as a hard disk or an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.

In addition, the control lines and the information lines are indicated so as to be necessary for the purpose of the explanation, and all of the control lines and the information lines are not always indicated in terms of products.

Claim 1:
A method for navigating a ship, comprising:
receiving a first position information (<NUM>) and a second position information (<NUM>) from a management server (<NUM>) having a storage device (<NUM>) for storing the first position information (<NUM>) of a first ship and the second position information (<NUM>) of a second ship wherein the first position information is received via a mobile telephone network from a user terminal (<NUM>) used in the first ship and the second position information (<NUM>) is transmitted via VHF radio from an AIS (Automatic Identification System) device used in the second ship and received via an AIS system (<NUM>), wherein the user terminal (<NUM>) comprises a radar display module (<NUM>) and a map display module (<NUM>);
displaying an icon indicating the first ship at a position designated by the first position information (<NUM>) on a nautical chart, and an icon indicating the second ship at a position designated by the second position information (<NUM>) on the nautical chart;
displaying a track of the first ship and a track of the second ship for a predetermined period from past to present;
setting for each of said first and second ships a warning area (<NUM>) as a fan-shaped area having a first center angle (<NUM>) and a radius corresponding to a first distance (<NUM>) in the moving direction of the first and second ships and setting a caution area (<NUM>) as a fan-shape area having a second center angle (<NUM>) larger that the first center angle (<NUM>) and a radius corresponding to a second distance (<NUM>) in the moving direction shorter than the first distance (<NUM>); and
displaying a notification of caution or a notification of warning in a case where the caution area (<NUM>) or the warning area (<NUM>) of the first ship overlaps the caution area (<NUM>) or the warning area (<NUM>) of the second ship;
displaying the notification of caution by the radar display module (<NUM>) and the map display module (<NUM>) when the caution area (<NUM>) of the first ship and the caution area (<NUM>) of the second ship overlap with each other; and
displaying the notification of warning by the radar display module (<NUM>) and the map display module (<NUM>) when the warning area (<NUM>) of the first ship and the warning area (<NUM>) of the second ship overlap with each other, wherein
an importance level and an emergency level of the notification of warning are higher than those of the notification of caution.