Abstract: A method for managing a database, each item of data in the database being associated with a timestamp and a data point, the timestamps being used as row keys for rows of a table in the database, the method comprising: obtaining a behavior characteristic of a user based on a previous data access to the database by the user; partitioning columns in the table into column families based on the obtained behavior characteristic and system configuration of the database; and causing data in the database to be stored in respective column families at least in part based on the associated data point.

Abstract: The present application discloses a virtualized wireless communication network and an establishing method thereof. The virtualized wireless communication network system includes a plurality of virtual nodes, the plurality of virtual nodes being divided into multiple virtual node cliques according to interference relations among the plurality of virtual nodes, wherein, each virtual node represents a wireless communication node; and a plurality of clique communication management modules that are one-to-one associated with the multiple virtual node cliques, wherein, each clique communication management module is configured to manage data exchange between an associated virtual node clique and other virtual node cliques, so as to emulate communication behavior of the wireless communication node. The present invention has many advantages such as high flexibility, good scalability, low cost and the like.

Abstract: The present invention discloses a method and system for managing a database. According to embodiments of the present invention, there is provided a method for managing a database, each item of data in the database being associated with a timestamp and a data point, the timestamps being used as row keys for rows of a table in the database, the method comprising: obtaining a behavior characteristic of a user based on a previous data access to the database by the user; partitioning columns in the table into column families based on the obtained behavior characteristic and system configuration of the database; and causing data in the database to be stored in respective column families at least in part based on the associated data point. There is further disclosed a corresponding system.

Abstract: The present invention provides a method and apparatus for data swap in a virtual machine environment. The present invention provides a method for data swap in a virtual machine environment, including: in response to a swap request from a virtual machine, looking up storage space associated with the swap request; and allocating to the virtual machine free physical storage space, in a host, which matches the storage space, so that the free physical storage space logically becomes available storage space to the virtual machine; the virtual machine is running on the host, and the storage space is physical storage space in the host.

Abstract: The present application discloses a virtualized wireless communication network and an establishing method thereof. The virtualized wireless communication network system includes a plurality of virtual nodes, the plurality of virtual nodes being divided into multiple virtual node cliques according to interference relations among the plurality of virtual nodes, wherein, each virtual node represents a wireless communication node; and a plurality of clique communication management modules that are one-to-one associated with the multiple virtual node cliques, wherein, each clique communication management module is configured to manage data exchange between an associated virtual node clique and other virtual node cliques, so as to emulate communication behavior of the wireless communication node. The present invention has many advantages such as high flexibility, good scalability, low cost and the like.

Abstract: In an approach for detecting islanding effect in a power electrical network topology, a computer processor finds, in the power electrical network topology, a point of common coupling between a load and a distributed generation with potential islanding effect as well as a substation supplying power to said point of common coupling; collects operating parameters of the power grid in vicinity of said point of common coupling as well as in vicinity of said substation; determines whether islanding effect exists in said distributed generation and the load in accordance with a variation characteristic of the operating parameters of the power grid in vicinity of said point of common coupling and the operating parameters of the power grid in vicinity of said substation. Higher degree of accuracy and sensitivity of detecting islanding effect is achieved without compromising the energy quality on user side according to embodiments of the present invention.

Abstract: The present application discloses a virtualized wireless communication network and an establishing method thereof. The virtualized wireless communication network system includes a plurality of virtual nodes, the plurality of virtual nodes being divided into multiple virtual node cliques according to interference relations among the plurality of virtual nodes, wherein, each virtual node represents a wireless communication node; and a plurality of clique communication management modules that are one-to-one associated with the multiple virtual node cliques, wherein, each clique communication management module is configured to manage data exchange between an associated virtual node clique and other virtual node cliques, so as to emulate communication behavior of the wireless communication node. The present invention has many advantages such as high flexibility, good scalability, low cost and the like.