摘要:
A novel approach to determining PageRank for web pages views the problem as being comparable to solving for an electromagnetic field problem. This view of ranking web pages enables appropriate entries for a matrix G of the web (or a subset), so that fast-solver techniques can be employed to iterate G, solving for ranks, or a dominant eigenstructure, achieving an O(N log N) performance in time and memory requirements. The specific solver technique that is used can be, for example, a fast multi-pole method (FMM), or a multilevel low-rank compression method. Once the problem is correctly formulated, it is not necessary to create the matrix G. Local information can be queried on demand by the solver. This approach can also be used to determine different scores of web pages, such as TrustRank, which is indicative of their trustworthiness.
摘要:
In one exemplary approach, a Schur complement-based boundary element method (BEM) is employed for predicting the motion of arbitrarily shaped three-dimensional particles under combined external and fluidic force fields. The BEM relies on modeling the surface of the computational domain, significantly reducing the number of unknowns when compared to volume-based methods. In addition, the Schur complement-based scheme enables a static portion of the computation to be computed only once for use in subsequent time steps, which leads to a tremendous reduction in solution time during time-stepping in the microfluidic domain. Parallelized oct-tree based O(N) multilevel iterative solvers are also used to accelerate the setup and solution costs.
摘要:
An approach that efficiently solves for a desired parameter of a system or device that can include both electrically large FMM elements, and electrically small QR elements. The system or device is setup as an oct-tree structure that can include regions of both the FMM type and the QR type. An iterative solver is then used to determine a first matrix vector product for any electrically large elements, and a second matrix vector product for any electrically small elements that are included in the structure. These matrix vector products for the electrically large elements and the electrically small elements are combined, and a net delta for a combination of the matrix vector products is determined. The iteration continues until a net delta is obtained that is within predefined limits. The matrix vector products that were last obtained are used to solve for the desired parameter.
摘要:
Redundancy extraction in electromagnetic simulation of an electronic device/system includes discretizing first and second spaced conductive layers of a computer model of an electronic device/system into first and second meshes M1 and M2. For each edge between cells of each mesh, a current flow across the edge in response to application of an exemplary bias to the geometry is determined. A square impedance matrix Z* is determined which, for each instance of equal magnitude and opposite direction current flows (EMODCF) in edges E1 and E2 of M1 and M2, has one less row and one less column than the total number of edges in M1 and M2. A voltage column vector V* is also determined which, for each instance of EMODCF, has one less row than the total number of edges in M1 and M2. A current column vector [I*]=[V*]/[Z*] is then determined.
摘要:
In a method of electronic design automation, discretized meshes of layers of current conducting materials of a computerized device model are determined. Each discretized mesh corresponds to the current conducting material of one model layer. For each discretized mesh, a corresponding impedance matrix having cells is determined. Each cell includes an impedance value Zij which is based on a voltage (Vi) induced in a cell i of the discretized mesh due to a current (Ij) flowing in a cell j of the discretized mesh. A subset of the cells, including impedance values, of the impedance matrices is dispatched to node computers via an electronic communications network. In response to dispatching the cells of the impedance matrices, charge densities estimated by the node computers to exist on a subset of the cells of the discretized meshes are returned.
摘要:
A novel approach to determining PageRank for web pages views the problem as being comparable to solving for an electromagnetic field problem. This view of ranking web pages enables appropriate entries for a matrix G of the web (or a subset), so that fast-solver techniques can be employed to iterate G, solving for ranks, or a dominant eigenstructure, achieving an O(N log N) performance in time and memory requirements. The specific solver technique that is used can be, for example, a fast multi-pole method (FMM), or a multilevel low-rank compression method. Once the problem is correctly formulated, it is not necessary to create the matrix G. Local information can be queried on demand by the solver. This approach can also be used to determine different scores of web pages, such as TrustRank, which is indicative of their trustworthiness.