Abstract: The present invention relates to an apparatus and a method for managing a buffer having three states on the basis of a flash memory and, more specifically, to an apparatus and a method for improving the performance of a database management system (DBMS) on the basis of the flash memory and a use life span of a storage device by reducing a writing operation for a flash memory device in which the writing operation is very slow in comparison with a reading operation, through an efficient buffer managing method and a new index node split policy. To this end, the buffer management device having three states on the basis of the flash memory according to an embodiment of the present invention comprises: a buffer memory unit; a list management unit; a buffer memory management unit; and a log buffer unit.

Abstract: The present invention is directed to a method of calculating the results of a moving k-nearest query and safe exit locations in a road network, and more particularly to a method and apparatus that receive a request from a client terminal and provide the results of a k-nearest query, a safe zone and safe exit locations together. In the present invention, a query is processed in a server, a request for a query from a querying user and the location information of the querying user are received from an LBS, the location information of the querying user is anonymized and then the query request is transferred to the server, and query results corresponding to the anonymized location information of the querying user are received from the server and then transferred to the querying user, thereby protecting the location information of the querying user.

Abstract: The present invention is directed to a method of calculating the results of a moving k-nearest query and safe exit locations in a road network, and more particularly to a method and apparatus that receive a request from a client terminal and provide the results of a k-nearest query, a safe zone and safe exit locations together. In the present invention, a query is processed in a server, a request for a query from a querying user and the location information of the querying user are received from an LBS, the location information of the querying user is anonymized and then the query request is transferred to the server, and query results corresponding to the anonymized location information of the querying user are received from the server and then transferred to the querying user, thereby protecting the location information of the querying user.

Abstract: The present invention relates to an apparatus and a method for managing a buffer having three states on the basis of a flash memory and, more specifically, to an apparatus and a method for improving the performance of a database management system (DBMS) on the basis of the flash memory and a use life span of a storage device by reducing a writing operation for a flash memory device in which the writing operation is very slow in comparison with a reading operation, through an efficient buffer managing method and a new index node split policy. To this end, the buffer management device having three states on the basis of the flash memory according to an embodiment of the present invention comprises: a buffer memory unit; a list management unit; a buffer memory management unit; and a log buffer unit.

Abstract: The present invention provides a flash memory controller for mapping the logical addresses to the physical addresses of memory including a plurality of blocks, each having a plurality of pages, wherein the memory controller includes a processor. The processor includes hot page decision unit and an address translation unit. The hot page decision unit classifies pages in each block into hot pages and cold pages based on a predetermined criterion. When there is a plurality of the classified hot pages, the address translation unit respectively arranges the classified hot pages in different target blocks. In accordance with this configuration, upon performing a merge operation, hot pages and cold pages are determined, and the hot pages are respectively distributed to empty blocks, so that concentration of an erase operation on a specific physical block may be avoided, thus wear-leveling may be performed more efficiently.

Abstract: The present invention provides a flash memory controller for mapping the logical addresses to the physical addresses of memory including a plurality of blocks, each having a plurality of pages, wherein the memory controller includes a processor. The processor includes hot page decision unit and an address translation unit. The hot page decision unit classifies pages in each block into hot pages and cold pages based on a predetermined criterion. When there is a plurality of the classified hot pages, the address translation unit respectively arranges the classified hot pages in different target blocks. In accordance with this configuration, upon performing a merge operation, hot pages and cold pages are determined, and the hot pages are respectively distributed to empty blocks, so that concentration of an erase operation on a specific physical block may be avoided, thus wear-leveling may be performed more efficiently.