The objective of process characterization is to demonstrate robustness manufacturing processes by understanding the relationship between key operating parameters and final performance. Technical information from study important for subsequent validation, this has become a regulatory expectation in recent years. Since performing at scale not practically feasible, development scale-down models that represent performance commercial essential achieve reliable characterization. In study, we...

This paper develops and analyzes two least-squares methods for the numerical solution of linear, stationary incompressible Newtonian fluid flow in three dimensions. Both approaches use L2 norm to define functionals. One is based on stress-velocity formulation (see section 3.2), it applies general boundary conditions. The other an equivalent pseudostress velocity 4.2), pure Dirichlet gradient vorticity can be obtained algebraically from this new tensor variable. It shown that homogeneous...

Large-scale renewable resources and novel smart-grid technologies continue to increase the complexity of power systems. As systems become more complex, accurate modeling for planning operation becomes a necessity. Inaccurate system models would result in an unreliable assessment security conditions could cause large-scale blackouts. This motivates need model parameter calibration, since some or all parameters either be unknown inaccurate. In this paper, extended Kalman filter is used...

Parallel methods are usually not applied to the time domain because of inherit sequentialness evolution. But for many evolutionary problems, computer simulation can benefit substantially from parallelization methods. In this paper, we present several such algorithms that actually exploit sequential nature evolution through a predictor-corrector procedure. This ensures convergence parallel scheme within fixed number iterations. The performance these novel algorithms, which derived classical...

An ensemble Kalman filter (EnKF) method is proposed to track dynamic states of generators. The algorithm the EnKF and its application generator state tracking are presented in detail. accuracy sensitivity analyzed with respect initial errors, measurement noise, unknown fault locations, time steps parameter errors. It demonstrated through simulation studies that even some errors parameters, developed can still effectively states.

Increasing complexity associated with large-scale renewable resources and novel smart-grid technologies necessitates real-time monitoring control. Our previous work applied the extended Kalman Alter (EKF) use of phasor measurement data (PMU) for dynamic state estimation. However, high computation creates significant challenges applications. In this paper, problem distributed estimation is investigated. One domain decomposition method proposed to utilize decentralized computing resources. The...

The complexity of power systems continue to increase as load demands grow and new energy technologies emerge. Efficient methodologies instrumentation are needed for real time monitoring control systems. Accurately tracking the state variables (rotor angle speed) is necessary system stability conditions assessing risks large-scale collapse. Previous work proposed an extended Kalman filter (EKF) method, which makes use data from phasor measurement units (PMU) corrects estimation predicted by...

Accurate numerical modeling of complex physical, chemical, and biological systems requires simulation capability over a large range length scales, with the ability to capture rapidly varying phenomena localized in space and/or time. Adaptive mesh refinement (AMR) is process for dynamically introducing local fine resolution on computational grids during solution process, response unresolved error computation. Fast adaptive composite-grid (FAC) methods are class algorithms that exploit...

Abstract In a sequence of papers, the author examined several statistical affinity measures for selecting coarse degrees freedom (CDOFs) or nodes (Cnodes) in algebraic multigrid (AMG) systems elliptic partial differential equations (PDEs). These were applied to set relaxed vectors that exposes problematic error components. Once CDOFs are determined using any one these measures, interpolation operator is constructed bootstrap AMG (BAMG) procedure. However, recent paper Kahl and Rottmann,...

This paper presents numerical results for the asynchronous version of fast adaptive composite-grid algorithm (AFACx). These confirm level-independent convergence bounds established theoretically in a companion paper. include case AFACx applied to first-order system least-squares finite element discretizations stationary Stokes equations on curvilinear mesh refinement grids.

In a recent series of articles, the author presented multiple-coarsening multigrid method for solving $S_n$ discretizations Boltzmann transport equation. This algorithm is applied to an integral equation scalar flux or moments. Although this very efficient over parameter regimes that describe realistic neutron/photon applications, improved methods can reduce computational cost are in paper. These derived through careful examination frequencies, particularly near nullspace, earlier...

Summary This paper presents parallel preconditioners and multigrid solvers for solving linear systems of equations arising from stochastic polynomial chaos formulations the diffusion equation with random coefficients. These are extensions preconditioner developed in an earlier strongly coupled elliptic partial differential that norm equivalent to can be factored into algebraic coupling component a diagonal component. The first preconditioner, which is applied system, obtained by sparsifying...

Stability limits are considered in power system planning and operations to estimate the available stability margins and, if possible, maximize use of transmission facilities. These important tasks influenced by configuration voltage boundary. This paper first propose a new method explore static conditions Cartesian coordinates instead polar coordinates. In this way, formulated singularity problem can be reduced solving set linear equations with respect real imaginary components nodal...

Power grids are operated in an increasingly complicated environment. However, operators lack effective and accurate tools for real-time monitoring control of power systems. The U.S. Department Energy, along with several utilities system operators, is making a major $108 million investment the Western Interconnection phasor measurement unit (PMU) installation application development. This network opens up many opportunities estimation prediction states real time, which enable to evaluate...

Summary This article develops an algebraic multigrid (AMG) method for solving systems of elliptic boundary‐value problems. It is well known that equations faces many challenges do not arise most scalar equations. These include strong intervariable couplings, multidimensional and possibly large near‐nullspaces, analytically unknown delicate selection coarse degrees freedom (CDOFs), complex construction intergrid operators. In this article, we consider only the CDOFs interpolation operator....

Power system model integrity is essential to many planning and operation tasks ensure the safety reliability of electricity delivery. Inaccurate models would result in unreliable assessment security conditions cause large-scale blackouts such as 2003 Northeast Blackout. This dictates a strong need for calibration verification, which should be done periodically preferably an automatic manner. Our previous work has demonstrated feasibility applying Extended Kalman Filter (EKF) calibrate...

Summary This paper presents a method for determining the relevant buses reduced models of power grid networks described by systems differential‐algebraic equations and constructing coarse‐grain dynamical systems. To determine these buses, time integration differential is not needed, but rather, stationary system analyzed. However, unlike stationary‐system approaches that only coarse generator approximating coherency generators, proposed analyzes graph Laplacian associated with admittance...

Abstract In a recent paper, the author examined correlation affinity measure for selecting coarse degrees of freedom (CDOFs) or nodes (C nodes) in systems elliptic partial differential equations (PDEs). This was applied to set relaxed vectors, which exposed near‐nullspace components PDE operator. Selecting CDOFs using this and constructing interpolation operators least‐squares procedure, an algebraic multigrid (AMG) method developed. However, there are several noted issues with AMG solver....

Abstract In a recent article, one of the authors developed multigrid technique for coarse‐graining dynamic powergrid models. A key component in this is relaxation‐based coarsening graph Laplacian given by network and its weighted graph, which represented admittance matrix. we use strategy to develop method solving static system nonlinear equations that arises through Ohm's law, so‐called powerflow equations. These are tightly knitted model full an algebraic‐differential with describing...

Addresses a project which aims to improve the management and assessment of student placements by providing electronic support based on business process design placement process. Seeks provide overall deliverables it is tasked achieve. The funded HEFCE as part their initiative promote good practice in teaching learning within higher education. A second article will follow reaches its conclusion. To aid effective activity, captured mapped all activities undertaken unit at Huddersfield...

Real-time computing has traditionally been considered largely in the context of single-processor and embedded systems, indeed, terms real-time computing, control systems are often mentioned closely related contexts. However, multinode specifically high-performance, cluster-computing remains relatively unexplored. Imposing realtime constraints on a parallel (cluster) environment introduces variety challenges with respect to formal verification system's timing properties. In this paper, we...