Abstract: A method and apparatus for performing an anti-virus scan of a file system. Intermediate scanning results are obtained for a file in the file system, prior to a scan of the file being completed. The intermediate scanning results are then stored in a database. The intermediate scanning results can be used to speed up subsequent scans, and to provide other useful information to an on-line anti-virus server. In a subsequent scan of the file system, a determination is made whether intermediate scanning results relating to the file are available in the database. If they are available for a particular type of intermediate scan, then a scan need not be performed for the file. If they are not, then the scan can be performed.

Abstract: An image is produced of a target region from tomographic measurements through statistical inversion. The target region is mapped with a grid of voxels. Unknowns in the voxels are the components of a vector-valued variable. A next version of the vector-valued variable is repeatedly generated by drawing for each component a value from a conditional distribution. Elements of a theory matrix indicate, what is the contribution of each voxel in the grid to a detection result. The non-zero elements of the theory matrix are stored in a compressed form. A proper subset of the elements of the theory matrix is decompressed for either updating the quantity Ax and/or calculating the quantity AjT(Ax), where A is the theory matrix, x is the vector-valued variable and AjT is the transpose of the j:th column of the theory matrix.

Abstract: A digital radar receiver generates the input signal which is a stream of complex numbers. The input signal is rearranged and sorted by measurement volumes, resulting in Doppler data vectors. Doppler data vectors are filtered using a number of different digital filters. The output Doppler data vectors of the filters together with the original Doppler data vector are the candidate signals. Each candidate signal is analyzed using several criteria in order to find the one signal which is most likely to be caused by precipitation and has the ground clutter removed by the filtering. The selected signal is then used to calculate the meteorological products. The selected signal is also used to derive a velocity value or velocity distribution while taking into account the effects of the filtering performed earlier.

Abstract: A method and apparatus for providing information to a security application at a client device. A server receives a request from the client device for information of an object at the client device. The request includes the signature information required by the server to identify the object. The server queries a database to determine the required information of the object and to determine information of at least one further object, and a response is sent to the client device. The response includes the information relating to the object, an identity of the at least one further object, and the information relating to the at least one further object.

Abstract: A method is provided for constructing a tomographic reconstruction through the application of statistical inversion. Unknowns associated with points of a reconstruction grid are represented with components of a vector-valued variable. A next version of the vector-valued variable is repeatedly created by drawing for each component a value from a conditional distribution. The components of a so generated version of the vector-valued variable are used as the tomographic reconstruction. The components are divided into sets, so that components in a set represent unknowns associated with mutually independent points of the reconstruction grid, or into independent collections. For at least two components of a set or at least two collections, the drawing of values from a conditional distribution is performed in parallel in a computer-implemented process.

Abstract: A digital radar receiver generates the input signal which is a stream of complex numbers. The input signal is rearranged and sorted by measurement volumes, resulting in Doppler data vectors. Doppler data vectors are filtered using a number of different digital filters. The output Doppler data vectors of the filters together with the original Doppler data vector are the candidate signals. Each candidate signal is analyzed using several criteria in order to find the one signal which is most likely to be caused by precipitation and has the ground clutter removed by the filtering. The selected signal is then used to calculate the meteorological products. The selected signal is also used to derive a velocity value or velocity distribution while taking into account the effects of the filtering performed earlier.

Abstract: An image is produced of a target region from tomographic measurements through statistical inversion. The target region is mapped with a grid of voxels. Unknowns in the voxels are the components of a vector-valued variable. A next version of the vector-valued variable is repeatedly generated by drawing for each component a value from a conditional distribution. Elements of a theory matrix indicate, what is the contribution of each voxel in the grid to a detection result. The non-zero elements of the theory matrix are stored in a compressed form. A proper subset of the elements of the theory matrix is decompressed for either updating the quantity Ax and/or calculating the quantity AjT(Ax), where A is the theory matrix, x is the vector-valued variable and AjT is the transpose of the j:th column of the theory matrix.

Abstract: A method and an arrangement are provided for producing a computed distribution of speeds of scatterers in a target volume (1701). An estimate distribution of speeds at which scatterers would move in the target volume is provided (1201). It is converted (1202) to a candidate autocorrelation function that represent autocorrelation data points that a pulse radar would measure from the current estimate distribution. The fit of a candidate ACF to a measured ACF is measured (1203). The estimate distribution is accepted if a measured fit fulfills a predefined acceptance criterion, or modified (1205) in which case processing returns to the conversion of the modified estimate distribution to an ACF. An accepted estimate distribution is output (1206) as a computed distribution of speeds that describes the actual distribution of speeds.

Abstract: A method and apparatus for performing an anti-virus scan of a file system. Intermediate scanning results are obtained for a file in the file system, prior to a scan of the file being completed. The intermediate scanning results are then stored in a database. The intermediate scanning results can be used to speed up subsequent scans, and to provide other useful information to an on-line anti-virus server. In a subsequent scan of the file system, a determination is made whether intermediate scanning results relating to the file are available in the database. If they are available for a particular type of intermediate scan, then a scan need not be performed for the file. If they are not, then the scan can be performed.

Abstract: A method and apparatus for providing information to a security application at a client device. A server receives a request from the client device for information of an object at the client device. The request includes the signature information required by the server to identify the object. The server queries a database to determine the required information of the object and to determine information of at least one further object, and a response is sent to the client device. The response includes the information relating to the object, an identity of the at least one further object, and the information relating to the at least one further object.