Abstract: A computer determines to which of a plurality of levels each of a plurality of road types for which a path search is performed corresponds, according to a distance between a departure point and a destination point. Next, the computer performs a first path search for the road type associated with a first level from the departure point to the destination point, and a second path search for the road type associated with the first level from the destination point to the departure point. Then, the computer performs a third path search for the road type associated with a second level according to a point obtained in the first path search and a point obtained in the second path search, and generates path information according to a result of the first path search, the second path search, and the third path search.

Abstract: A data management method including accepting a request of polygon data including data pertaining to latitude/longitude of each vertex of a polygon, specifying a minimum unit rectangle matching a minimum bounding rectangle of the polygon or including the minimum bounding rectangle from plural unit rectangles formed by recursively dividing a two-dimensional space including a latitude/longitude range and being equally divided in X and Y directions in the same number, generating a character string by assigning values to the minimum unit rectangle or all unit rectangles including the minimum unit rectangle in correspondence with the number of divided parts of the two-dimensional space in the X and Y directions, and alternately arranging the values, in the X or Y direction, starting from values corresponding to a large unit rectangle among the unit rectangles, and storing the polygon data in correspondence with a key including the character string.

Abstract: A computer determines to which of a plurality of levels each of a plurality of road types for which a path search is performed corresponds, according to a distance between a departure point and a destination point. Next, the computer performs a first path search for the road type associated with a first level from the departure point to the destination point, and a second path search for the road type associated with the first level from the destination point to the departure point. Then, the computer performs a third path search for the road type associated with a second level according to a point obtained in the first path search and a point obtained in the second path search, and generates path information according to a result of the first path search, the second path search, and the third path search.

Abstract: An information management method to be executed by a computer, the information management method includes: accepting a registration request including information in which latitude and longitude are included, and correspondence information corresponding to the position information; generating one character string by alternately arraying one character of the latitude and another one character of the longitude, each of the one character and the other one character is in a same digit regarding all of the digits of each of the latitude and the longitude, or some digits from the least significant digit of each of the latitude and the longitude; and storing the correspondence information in a storage unit in a manner correlated with the character string as a key.

Abstract: A computer refers to observation data formed by observing, at plural timings, a travel time taken for a vehicle to pass through a road section. The computer then obtains a first statistical value of the travel time at a first time of a prediction target day based on the observation data. The computer further obtains a second statistical value of the travel time at a second time later than the first time. The computer then calculates a prediction value of the travel time at the second time based on the first statistical value, the second statistical value, and the travel time observed at the first time. The computer calculates the prediction value such that a difference between the second statistical value and the prediction value at the second time is smaller than a difference between the first statistical value and the travel time observed at the first time.

Abstract: A computer performs a path search from a first node to a second node by using nodes and links connecting two nodes and to which a cost is set. A first search method is used to search for one node from among nodes to be searched which are adjacent to the searched-for node and have not yet been searched for. Then, the distance between the searched-for node and the second node is recorded, and the searched-for node is recorded as an already-searched-for node. Next, the first search method is changed to a second search method in which a number of nodes to be searched is prevented from increasing according to distances between the second node and two or more searched-for nodes obtained as a result of performing searching and recording plural times. Then, path information is generated according to a node searched for by the second search method.

Abstract: An information management method to be executed by a computer, the information management method includes; accepting a registration request that includes identification information of a mobile device, and position information of the mobile device that includes latitude and longitude; generating a value that includes the identification information followed by information that indicates a date and time when the registration request is accepted; storing the position information in a first storage unit in a manner correlated with the value; generating another value that includes the information that indicates the date and time followed by the identification information; storing the position information in a second storage unit in a manner correlated with the other value; storing the position information in a third storage unit in a manner correlated with the identification information; and storing the identification information in a fourth storage unit in a manner correlated with the position information.

Abstract: A search method to be implemented in a computer which performs a process to search searching information including a plurality of items that are targets of information search, includes, in response to receiving a search request for the searching information, comparing one or more first character strings stored in a storage in a related manner to information related to a source of the search request, and a second character string specified in the search request, in order to judge the item corresponding to the second character string based on a result of the comparing, and searching the searching information using the second character string as a search condition related to the item that is judged as corresponding to the second character string.

Abstract: A computer performs a path search from a departure point to a destination point and a path search from the destination point to the departure point while changing a target from a road type at a level other than the highest level to a road type at a higher level, according to a first grouping of a plurality of road types, and performs a path search for the road type at the highest level in a first process. Next, the computer performs similar path searches in an area to be searched based on a result of the first process, according to a second grouping in which a greater number of road types is classified as the highest level in a second process. Then, the computer generates path information according to a result of the second process.

Abstract: A computer performs a path search from a departure point to a destination point and a path search from the destination point to the departure point while changing a target from a road type at a level other than the highest level to a road type at a higher level, according to a first grouping of a plurality of road types, and performs a path search for the road type at the highest level in a first process. Next, the computer performs similar path searches in an area to be searched based on a result of the first process, according to a second grouping in which a greater number of road types is classified as the highest level in a second process. Then, the computer generates path information according to a result of the second process.

Abstract: A data management method including accepting a request of polygon data including data pertaining to latitude/longitude of each vertex of a polygon, specifying a minimum unit rectangle matching a minimum bounding rectangle of the polygon or including the minimum bounding rectangle from plural unit rectangles formed by recursively dividing a two-dimensional space including a latitude/longitude range and being equally divided in X and Y directions in the same number, generating a character string by assigning values to the minimum unit rectangle or all unit rectangles including the minimum unit rectangle in correspondence with the number of divided parts of the two-dimensional space in the X and Y directions, and alternately arranging the values, in the X or Y direction, starting from values corresponding to a large unit rectangle among the unit rectangles, and storing the polygon data in correspondence with a key including the character string.

Abstract: A computer determines to which of a plurality of levels each of a plurality of road types for which a path search is performed corresponds, according to a distance between a departure point and a destination point. Next, the computer performs a first path search for the road type associated with a first level from the departure point to the destination point, and a second path search for the road type associated with the first level from the destination point to the departure point. Then, the computer performs a third path search for the road type associated with a second level according to a point obtained in the first path search and a point obtained in the second path search, and generates path information according to a result of the first path search, the second path search, and the third path search.

Abstract: A computer performs a path search from a first node to a second node by using nodes and links connecting two nodes and to which a cost is set. A first search method is used to search for one node from among nodes to be searched which are adjacent to the searched-for node and have not yet been searched for. Then, the distance between the searched-for node and the second node is recorded, and the searched-for node is recorded as an already-searched-for node. Next, the first search method is changed to a second search method in which a number of nodes to be searched is prevented from increasing according to distances between the second node and two or more searched-for nodes obtained as a result of performing searching and recording plural times. Then, path information is generated according to a node searched for by the second search method.

Abstract: An information management method to be executed by a computer, the information management method includes: accepting a registration request including information in which latitude and longitude are included, and correspondence information corresponding to the position information; generating one character string by alternately arraying one character of the latitude and another one character of the longitude, each of the one character and the other one character is in a same digit regarding all of the digits of each of the latitude and the longitude, or some digits from the least significant digit of each of the latitude and the longitude; and storing the correspondence information in a storage unit in a manner correlated with the character string as a key.

Abstract: An information management method to be executed by a computer, the information management method includes; accepting a registration request that includes identification information of a mobile device, and position information of the mobile device that includes latitude and longitude; generating a value that includes the identification information followed by information that indicates a date and time when the registration request is accepted; storing the position information in a first storage unit in a manner correlated with the value; generating another value that includes the information that indicates the date and time followed by the identification information; storing the position information in a second storage unit in a manner correlated with the other value; storing the position information in a third storage unit in a manner correlated with the identification information; and storing the identification information in a fourth storage unit in a manner correlated with the position information.