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A heuristic procedure for one dimensional bin packing

In this paper we develop new Newton and conjugate gradient algorithms on the Grassmann and Stiefel manifolds. These manifolds represent the constraints that arise in such areas as the symmetric eigenvalue problem, nonlinear eigenvalue problems, electronic structures computations, and signal

show how explicitly incorporating the notion of 'sparseness' improves the found decompositions. Additionally, we provide complete MATLAB code both for standard NMF and for our extension. Our hope is that this will further the application of these methods to solving novel data

Recently, separability inequalities are derived with multiqubit states [S. M. Roy, Phys. Rev. Lett. 94, 010402 (2005)]. We introduce new kind of entanglement, which is rotationally invariant. We de-rive quadratic separability inequalities with multipartite states. The quadratic separability inequality can be used as a witness of rotationally invariant two-partite entanglement. We discuss that the quadratic sep-arability inequality implies standard Bell inequalities. It is also proved that when the two measured observables are assumed to precisely an-ticommute, a stronger quadratic inequality can be used as a witness of rotationally variant two-partite entanglement. We discuss that the stronger quadratic inequality implies an inequality stronger than stan-dard Bell inequalities. Our argumentations imply that standard Bell inequalities are derived under the assumption that every quantum state is rotationally invariant. We discuss the implication of anticommute along with rotational invariance. PACS: 03.67.Mn, 03.65.Ca

Context. Hydrogen peroxide (HOOH) was recently detected toward ρ Oph A. Subsequent astrochemical modeling that included reactions in the gas phase and on the surface of dust grains was able to explain the observed abundance, and highlighted the importance of grain chemistry in the formation of HOOH as an intermediate product in water formation. This study also predicted that the hydroperoxyl radical HO2, the precursor of HOOH, should be detectable. Aims. We aim at detecting the hydroperoxyl radical HO2 in ρ Oph A. Methods. We used the IRAM 30 m and the APEX telescopes to target the brightest HO2 lines at about 130 and 260 GHz. Results. We detect five lines of HO2 (comprising seven individual molecular transitions). The fractional abundance of HO2 is found to be about 10−10, a value similar to the abundance of HOOH. This observational result is consistent with the prediction of the above mentioned astrochemical model, and thereby validates our current understanding of the water formation on dust grains. Conclusions. This detection, anticipated by a sophisticated gas-grain chemical model, demonstrates that models of grain chemistry have improved tremendously and that grain surface reactions now form a crucial part of the overall astrochemical network.

We present algorithms for testing the satisfiability and finding the tightened transitive closure of conjunctions of addition constraints of the form ±x ± y ≤ d and bound constraints of the form ±x ≤ d where x and y are integer variables and d is an integer constrant. The running time

for these constraints yields estimates for the unknown positions of the nodes in the network. Providing that the constraints are tight enough, simulation illustrates that this estimate becomes close to the actual node positions. Additionally, a method for placing rectangular bounds around the possible positions for all

In this paper we describe a new technique for general purpose interactive segmentation of N-dimensional images. The user marks certain pixels as “object” or “background” to provide hard constraints for segmentation. Additional soft constraints incorporate both boundary and region information. Graph

not explicitly dealt with constraints imposed by real world environments. This article presents COBWEB, a conceptual clustering system that organizes data so as to maximize inference ability. Additionally, COBWEB is incremental and computationally economical, and thus can be flexibly applied in a variety