In this paper, we propose an efficient algorithm to reduce the voltage noises for on-chip power/ground (P/G) networks of VLSI. The new method is based on the sequence of linear programming (SLP) as the optimization engine, and partitioning scheme for dealing with large-sized circuits. We show that by directly optimizing the decoupling capacitor (decap) areas as the objective function and using ...

An adjoint model for a 2D finite element Galerkin shallow water model is developed using the Independent Set Perturbation Adjoint method (ISP-Adjoint, [33]). Its performance in a full 4-D VAR setup with a limited area is assessed by comparing with the adjoint model derived by the automatic differentiation approach, where it is used for optimising the initial conditions. It is shown that ISP-Adj...

We consider 1 + 1 dimensional SU(N) gauge theory coupled to a multiplet of massive Dirac fermions transforming in the adjoint representation of the gauge group. The only global symmetry of this theory is a U(1) associated with the conserved Dirac fermion number, and we study the theory at variable, non-zero densities. The high density limit is characterized by a deconfined Fermi surface state w...

Traveltime tomography with shot-based eikonal equation fixes shot positions then relies on inversion to resolve any contradicting information between independent shots and achieve a possible cost-function minimum. On the other hand, the double-square-root (DSR) eikonal equation that describes the whole survey, while providing the same first-arrival traveltimes, allows not only the receivers but...

Wavefield tomography represents a family of velocity model building techniques based on full waveforms as the input and seismic wavefields as the information carrier. When these techniques are implemented in the image domain and use seismic images as the input, they are referred to as image-domain wavefield tomography. The objective function for image-domain approach is designed to optimize the...

Prestack wave equation migration using the double square root equation produces prestack image volumes free of artifacts, even in the presence of multipathing due to complex structure. In particular image gathers in angle or offset ray parameter are flat at correct velocity, and gathers in offset are concentrated at zero offset. Differential semblance measures the deviation from flatness or con...

Waveform inversion and wave-equation migration velocity analysis share one common feature: both techniques exploit information available in the same source and receiver wavefields reconstructed at all times and at all locations in space. These two wavefields are reconstructed from the same source function and observed data as solutions to the same wave-equation. Both techniques invert for the s...