Electrical impedance tomography (EIT) was used to monitor the movement of a fluorinated hydrocarbon dense nonaqueous phase liquid (DNAPL) through a saturated porous medium within a laboratory column. Impedance measurements were made using a horizontal plane of 12 electrodes positioned at regular intervals around the centre of the column. A 2D inversion algorithm, which incorporated the cylindri...

In the first part of the article, the column and the bag experiments concerning removal of polycyclic aromatic hydrocarbons (PAHs) and nonpolar oil (NPO) from tunnel wash waters using organic sorbent materials have been described. This part presents the results of removal of toxic metals. The metals of concern (Al, As, Cd, Cr, Cu, Fe, Pb, Mo, Ni, and Zn) were selected based on the priority toxi...

Application of dispersants in shallow water remains an issue of debate within the spill response community. An experimental oil spill to evaluate potential environmental impacts and benefits of applying dispersants to spills in shallow water has therefore been under consideration. One site being considered was Matagorda Bay, on the Texas coast. Coupled three-dimensional oil spill and hydrodynam...

We investigate two cutting problems and their variants in which orthogonal rotations are allowed. We present a dynamic programming based algorithm for the Two-dimensional Guillotine Cutting Problem with Value (GCV) that uses the recurrence formula proposed by Beasley and the discretization points defined by Herz. We show that if the items are not so small compared to the dimension of the bin, t...

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...

[1] Measurements of the OH column abundance over the Jet Propulsion Laboratory’s Table Mountain Facility (TMF) have been made since July 1997 at 10 –80 solar zenith angle using a Fourier transform ultraviolet spectrometer. The measured OH column at any solar zenith angle is typically larger in the afternoon than in the morning. The variations observed in the OH column abundance appear to result...

This paper presents our investigations on a hybrid constraint programming based column generation (CP-CG) approach to nurse rostering problems. We present a complete model to formulate all the complex real-world constraints in several benchmark nurse rostering problems. The hybrid CP-CG approach is featured with not only the effective relaxation and optimality reasoning of linear programming bu...

Row-column designs (RCD) are used in experimental situations when the heterogeneity in the experimental material is due to two cross classified sources. In such trials, there may be situations in which the experimenter wants to compare a set of new (test) treatments with an already existing (control) treatment. The experimenter is interested in comparing test treatments with the control with mo...

Beginning with triangular fuzzy inputs representing fuzzy ratio judgments, we experiment with two procedures to obtain fuzzy relative priorities in the Analytic Hierarchy Process. We extend the simple geometric mean and simple normalized column sum methods with fuzzy arithmetic. When the pairwise comparisons are fully consistent the methods produce identical results, but they diverge in the pre...

Collinearity and eye of origin were recently discovered to guide attention: Target search is impaired if it is overlapping with a collinear structure (Jingling & Tseng, 2013) but enhanced if the target is an ocular singleton (Zhaoping, 2008). Both are proposed to occur in V1, and we study their interaction here. In our 9 × 9 search display (Experiment 1), all columns consisted of horizontal bar...