Constraint-reduction schemes have been proposed for the solution by interior-point methods of linear programs with many more inequality constraints than variables in standard dual form. Such schemes have been shown to be provably convergent and highly efficient in practice. A critical requirement of these schemes is the availability of an initial dual-feasible point. In this paper, building on ...

We examine the formation of giant elliptical galaxies using their globular cluster (GC) systems as probes of their evolutionary history. The bimodal distributions of GC metallicities in such galaxies are often cited as evidence for the formation of giant elliptical galaxies through mergers involving gas-rich spirals, with the metal-rich GCs forming during the merger process. We explore an alter...

We study the stability of the giant gravitons in the string theory background with NSNS B field. We consider the perturbation of giant gravitons formed by a probe D(8− p) brane in the background generated by D(p− 2)D(p) branes for 2 ≤ p ≤ 5. We use the quadratic approximation to the brane action to find the equations of motion. The vibration modes for ρ , φ and r are coupled, while those of xk’...

We present a predictor{corrector non{interior path following algorithm for the monotone linear complementarity problem based on Chen{Harker{Kanzow{Smale smoothing techniques. Although the method is modeled on the interior point predictor{ corrector strategies, it is the rst instance of a non{interior point predictor{corrector algorithm. The algorithm is shown to be both globally linearly conver...

-A new feasible direction method for linear programming problems is presented. The method is not boundary following. The method proceeds from a feasible interior point in a direction that improves the objective function until a point on a constraint surface is met. At this point searches are initiated in the hyperplane of constant function value by using projections of the bounding constraints ...

We propose a BFGS primal-dual interior point method for minimizing a convex function on a convex set defined by equality and inequality constraints. The algorithm generates feasible iterates and consists in computing approximate solutions of the optimality conditions perturbed by a sequence of positive parameters μ converging to zero. We prove that it converges q-superlinearly for each fixed μ....

To evaluate the quality of the train timetable roundly, train timetable stability is defined based on the analysis of the interior and exterior factors affecting the timetable stability. The exterior factors include the grade of the railway lines, the blocking system type, the station interlocking type, the leading locomotive performance and the average mileage of the sections. The interior fac...

In this paper we continue the development of a theoretical foundation for efficient primal-dual interior-point algorithms for convex programming problems expressed in conic form, when the cone and its associated barrier are self-scaled (see [NT97]). The class of problems under consideration includes linear programming, semidefinite programming and convex quadratically constrained quadratic prog...

Paying off the mortgage, once a widespread rite of passage for homeowners approaching retirement, has become less common in recent years. Concerns are mounting that the increased prevalence of housing debt among older homeowners could compromise financial security in retirement by expanding housing affordability problems, crimping essential nonhousing spending, increasing vulnerability to home ...