This paper presents a new warmstarting technique in the context of a primal-dual column generation method applied to solve a particular class of combinatorial optimization problems. The technique relies on calculating an initial point and on solving auxiliary linear optimization problems to determine the step direction needed to fully restore primal and dual feasibilities after new columns arri...

We study the problem of instance segmentation in biological images with crowded and compact cells. We formulate this task as an integer program where variables correspond to cells and constraints enforce that cells do not overlap. To solve this integer program, we propose a column generation formulation where the pricing program is solved via exact optimization of very small scale integer progr...

ABSTRACT: This paper proposes the Model Predictive Control (MPC) scheme in a bubble cap distillation column . Even though PID controllers are widely used for the control of nonlinear system, there is a need for optimizing and conservation of energy. Here, MPC scheme is designed and it is used for controlling the composition in distillation columns.The tuning of PID controller is done using Sund...

Optimization of queries with conjunctive predicates for main memory databases remains a challenging task. The traditional way of optimizing this class of queries relies on predicate ordering based on selectivities or ranks. However, the optimization of queries with conjunctive predicates is a much more challenging task, requiring a holistic approach in view of (1) an accurate cost model that is...

in recent year, the evolutionary structural optimization (eso) method, has been applied as an effective tool for structures design. the concept of eso method is to use the finite element  results in each iteration of process and removal of inefficient material based on these results. in this method there are several experimental parameters such as rejection rate and evolutionary rate that are e...

We present a cache locality optimization technique that can optimize a loop nest even if the arrays referenced have different layouts in memory. Such a capability is required for a global locality optimization framework that applies both loop and data transformations to a sequence of loop nests for optimizing locality. Our method finds a nonsingular iteration-space transformation matrix such th...

In this paper, we present a column-and-constraint generation algorithm to solve twostage robust optimization problems. Compared with existing Benders-style cutting plane methods, the column-and-constraint generation algorithm is a general procedure with a unified approach to deal with optimality and feasibility. A computational study on a twostage robust location-transportation problem shows th...

Fig. 2 Results for three HS pulses: a high bandwidth pulse (row 1), a reduced bandwidth pulse (row 2), and an optimized pulse with reduced bandwidth (row 3). Flip-angle maps are calculated on the grid of targeted static and RF field variations (column 1) and within an axial slice of the human brain (column 2). Frequency profiles for B1/ B1,nom intensities of 0.35, 0.50, 0.75, and 1.00 are shown...

Flexibility in the manufacturing of cold-formed steel (CFS) cross-sectional shapes provides a unique opportunity to improve load-carrying capacity these elements, leading more efficient and economic structural systems. This paper presents practical constrained optimization methodology for pin-ended anti-symmetric CFS beam-columns members with different lengths subjected various combinations axi...

Startup of distillation columns is one of the most difficult operations of chemical processes. Since it often lasts a period of time, leads to off-products and costs much energy, optimization of startup operating policies for distillation columns is of great interest in process industry. Most previous studies on column startup have been restricted to theoretical investigations such as modeling,...