Many interesting and important constrained optimization problems in mathematical programming can be translated into an equivalent linear projection equation u = P u ? (Mu + q)]: Here, P () is the orthogonal projection on some convex set (e.g. = R n +) and M is a positive semideenite matrix. This paper presents some new methods for solving a class of linear projection equations. The search direc...

The recent discovery by the Pierre Auger collaboration of anisotropy in the arrival directions of the highest energy cosmic rays, correlated with the positions of nearby active galactic nuclei [1, 2], encourages the search for counterpart TeV gammaray emission. Approximately half of the sky viewed by the southern hemisphere Pierre Auger experiment is also visible at reasonable elevations for th...

We present an infeasible-interior-point algorithm for monotone linear complementarity problems in which the search directions are affine scaling directions and the step lengths are obtained from simple formulae that ensure both global and superlinear convergence. By choosing the value of a parameter in appropriate ways, polynomial complexity and convergence with Q-order up to (but not including...

A new method for two-class linear discriminant analysis, called "removal of classification structure", is proposed. Its novelty lies in the transformation of the data along an identified discriminant direction into data without discriminant information and iteration to obtain the next discriminant direction. It is free to search for discriminant directions oblique to each other and ensures that...

The efficient solution of large-scale linear and nonlinear optimization problems may require exploiting any special structure in them in an efficient manner. We describe and analyze some cases in which this special structure can be used with very little cost to obtain search directions from decomposed subproblems. We also study how to correct these directions using (decomposable) preconditioned...

The Polak-Ribière-Polyak conjugate gradient algorithm is a useful tool of unconstrained numerical optimization. Efficient implementations of the algorithm usually perform line searches satisfying the strong Wolfe conditions. It is well known that these conditions do not guarantee that the successive computed directions are descent directions. This paper proposes a relaxation of the strong Wolfe...

This paper discusses computational experiments with linear optimization problems involving semidefinite, quadratic, and linear cone constraints (SQLPs). Many test problems of this type are solved using a new release of SDPT3, a Matlab implementation of infeasible primal-dual path-following algorithms. The software developed by the authors uses Mehrotratype predictor-corrector variants of interi...

Machine teaching (MT) studies the task of designing a training set. Specifically, given a learner (e.g., an artificial neural network or a human) and a target model, a teacher aims to create a training set which results in the target model being learned. MT applications include optimal education design for human learners and computer security where adversaries aim to attack learning-based syste...

In visual search, items defined by a unique feature are found easily and efficiently. Search for a moving target among stationary distractors is one such efficient search. Search for a stationary target among moving distractors is markedly more difficult. In the experiments reported here, we confirm this finding and further show that searches for a stationary target within a structured flow fie...

Œe amount of data published openly on the web is increasing rapidly. Most people either use web search or specialised data portals, which are repositories of datasets, to search for data. Most data portals today use similar faceted search interfaces. In this paper we focus on how a large governmental data portal in the UK supports users in conducting complex search tasks involving data. Based o...