JavaScript is disabled for your browser. Some features of this site may not work without it.
Browsing Center for Advanced Computing by Title
Now showing items 1-20 of 150
-
An Accelerated Interior Point Method Whose Running Time Depends Only on A
Vavasis, Stephen A.; Ye, Yinyu (Cornell University, 1993-10)We propose a "layered-step" interior point (LIP) algorithm for linear programming. This algorithm follows the central path, either with shortsteps or with a new type of step called a "layered least squares" (LLS)step. The ... -
Access Normalization: Loop Restructuring for NUMA Compilers
Li, Wei; Pingali, Keshav (Cornell University, 1992-07)A common feature of many scalable parallel machines is non-uniform memory access - a processor can access data in its local memory ten to a thousand times faster than it can access local data. In addition, when a ... -
Access Normalization: Loop Restructuring for NUMA Compilers
Li, Wei; Pingali, Keshav (Cornell University, 1992-07)A common feature of many scalable parallel machines is non-uniform memory access - a processor can access data in its local memory ten to a thousand times faster than it can access local data. In addition, when a ... -
Accurate Solution of Weighted Least Squares by Iterative Methods
Bobrovnikova, Elena Y.; Vavasis, Stephen A. (Cornell University, 1997-02-06)We consider the weighted least-squares (WLS) problem with a very ill-conditioned weight matrix. Weighted least-squares problems arise in many applications including linear programming, electrical networks, boundary value ... -
Advanced Computing Research Institute Annual Research Activity Report September 1993 - September 1994
Pingali, Keshav (Cornell University, 1994-10)The Advanced Computing Research Institute (ACRI) is a unit of the Cornell Theory Center and is affiliated with the Cornell Computer Science Department. The ACRI is concerned with research in scientific computation and its ... -
Advanced Computing Research Institute Semi-annual Research Activity Report, April 1992 - September 1992
Coleman, Thomas F. (Cornell University, 1992-11)The Advanced Computing Research Institute (ACRI) is a unit of the Cornell Theory Center and is affiliated with the Cornell Computer Science Department. The ACRI is concerned with research in scientific computation ... -
Advantages of Differential Dynamic Programming Over Newton's Method for Discrete-time Optimal Control Problems
Liao, Li-zhi; Shoemaker, Christine A. (Cornell University, 1992-07)Differential Dynamic Programming (DDP) and stagewise Newton's method are both quadratically convergent algorithms for solving discrete time optimal control problems. Although these two algorithms share many theoretical ... -
An Affine Scaling Algorithm for Minimizing Total Variation in Image Enhancement
Li, Yuying; Santosa, Fadil (Cornell University, 1994-12)A computational algorithm is proposed for image enhancement based on total variation minimization with constraints. This constrained minimization problem is introduced by Rudin et al [13,14,15] to enhance blurred and noisy ... -
All-Electron Study of Gradient Corrections to the Local Density Functional in Metallic Systems
Khein, Alexander; Singh, D. J.; Umrigar, C. J. (Cornell University, 1994-08)Using the all-electron Linearized Augmented Plane Wave (LAPW) method, we calculate the effect of including gradient corrections to the exchange correlation functional on the structural properties of the simple metal Al, ... -
Analysis of the Early Workload on the Cornell Theory Center IBM SP2
Hotovy, Steven; Schneider, David; O'Donnell, Timothy (Cornell University, 1996-01)Parallel computers have matured to the point where they are capable of running a significant production workload. Characterizing this workload, however, is far more complicated than for the single-processor case. Besides ... -
The Application of Automatic Differentiation to Problems in Engineering Analysis
Chinchalkar, Shirish (Cornell University, 1993-12)Automatic differentiation is a technique of computing the derivative of a function or a subroutine written in a higher level language such as FORTRAN or C. Significant progress has been made in this field in the last few ... -
Approximation with Kronecker Products
Loan, Charles Van; Pitsianis, Nikos (Cornell University, 1992-11)Let A be an m-by-n matrix with m=m1m2 and n=n1n2. We consider the problem of finding (mathematical formula omitted) so that (mathematical formula omitted) is minimized. This problem can be solved by computing the ... -
ARCH, An Object-Oriented Library for Asynchronous and Loosely Synchronous System Programming
Adamo, Jean-Marc (Cornell University, 1995-12)ARCH is a C++-based library for asynchronous and loosely synchronous system programming. The current version offers a set of programming constructs that are outlined below: *** Threads: The construct is presented as a ... -
An Aspect Ratio Bound for Triangulating a d-grid Cut by a Hyperplane
Mitchell, Scott A.; Vavasis, Stephen A. (Cornell University, 1995-11)We consider the problem of triangulating a d-dimensional uniform grid of d-cubes that is cut by a k-dimensional affine subspace. The goal is to obtain a triangulation with bounded aspect ratio. To achieve this goal, we ... -
Automatic Optimization
Liao, Aiping (Cornell University, 1995-07)We propose some automatic techniques for unconstrained optimization with the objective function given by some computer program. We show that the Newton step can be calculated in O(m2) operations where m is the number of ... -
Avalanches, Scaling, and Coherent Noise
Newman, M.E.J.; Sneppen, Kim (Cornell University, 1996-03)We present a simple model of a dynamical system driven slowly by externally-imposed coherent noise. Although the system never becomes critical in the sense of possessing spatial correlations of arbitrarily long range, it ... -
BLAS Based on Block Data Structures
Henry, Greg (Cornell University, 1992-02)The optimization of the BLAS is discussed, with examples given for the IBM superscalar RISC S/6000. The approach suggested is to use block data structures based on store-by-block schemes. We give results and ... -
Block Factorizations on a Cluster of RS/6000s
Henry, Greg; Hoisie, Adolfy (Cornell University, 1992-02)This paper discusses optimizing computational linear algebra algorithms on a ring cluster of IBM RS/6000s. We offer the results of a block Cholesky factorization and the underlying BLAS to demonstrate the advantage ... -
Calculation of Pseudospectra by the Arnoldi Iteration
Toh, Kim-Chuan; Trefethen, Lloyd N. (Cornell University, 1994-05)The Arnoldi iteration, usually viewed as a method for calculating eigenvalues, can also be used to estimate pseudospectra. This possibility may be of practical importance, for in applications involving highly non-normal ... -
Case Study in KSR Programming: Finding Outliers by the Minimum Volume Ellipsoid Method
Bergmark, Donna; Crovella, Mark (Cornell University, 1992-09)This case study describes the enablement of a parallel application on Cornell Theory Center's KSR1, a highly parallel machine from Kendall Square Research. The application is from statistics, and exposes some interesting ...