An interactive graphics package for the automatic node renumbering of finite element matrices

An interactive graphics software package which allows users to display the non-zero structure of large sparse symmetric materials was described and methods used to implement it as a portable FORTRAN callable subroutine were summarized. In particular, the system permits the display of the resulting matrix after reordering the rows and columns, with the reordering scheme either defined by the user or automatically generated by the program with the aim of reducing matrix bandwidth and profile. Although the primary application of the package has been to the finite element analysis of structures, it is equally well suited to the many other areas of engineering and science which use sparse matrices

Amorphous silica between confining walls and under shear: a computer simulation study

Molecular dynamics computer simulations are used to investigate a silica melt confined between walls at equilibrium and in a steady-state Poisseuille flow. The walls consist of point particles forming a rigid face-centered cubic lattice and the interaction of the walls with the melt atoms is modelled such that the wall particles have only a weak bonding to those in the melt, i.e. much weaker than the covalent bonding of a Si-O unit. We observe a pronounced layering of the melt near the walls. This layering, as seen in the total density profile, has a very irregular character which can be attributed to a preferred orientational ordering of SiO4 tetrahedra near the wall. On intermediate length scales, the structure of the melt at the walls can be well distinguished from that of the bulk by means of the ring size distribution. Whereas essentially no structural changes occur in the bulk under the influence of the shear fields considered, strong structural rearrangements in the ring size distribution are present at the walls as far as there is a slip motion. For the sheared system, parabolic velocity profiles are found in the bulk region as expected from hydrodynamics and the values for the shear viscosity as extracted from those profiles are in good agreement with those obtained in pure bulk simulations from the appropriate Green-Kubo formula.Comment: 23 pages of Late

Density minimum and liquid-liquid phase transition

We present a high-resolution computer simulation study of the equation of state of ST2 water, evaluating the liquid-state properties at 2718 state points, and precisely locating the liquid-liquid critical point (LLCP) occurring in this model. We are thereby able to reveal the interconnected set of density anomalies, spinodal instabilities and response function extrema that occur in the vicinity of a LLCP for the case of a realistic, off-lattice model of a liquid with local tetrahedral order. In particular, we unambiguously identify a density minimum in the liquid state, define its relationship to other anomalies, and show that it arises due to the approach of the liquid structure to a defect-free random tetrahedral network of hydrogen bonds.Comment: 5 pages, 4 figure

Process for forming layers on substrates

The present invention is generally directed to various processes and systems for forming layers and coatings on substrates, such as semiconductor wafers and solar cells. In one embodiment, the process of the present invention is directed to forming a layer on a substrate from a liquid precursor. The liquid precursor is atomized and exposed to light energy. Besides light energy, the parent material may also be exposed to an electric field and/or to sonic energy. In an alternative embodiment of the present invention a stress measurement device monitors stress in the substrate as a layer is deposited on the substrate. This stress measurement information is then sent to a controller for automatically controlling the amount of energy, such as light energy being emitted onto the substrate

Dark Energy Survey year 1 results: Galaxy clustering for combined probes

We measure the clustering of DES year 1 galaxies that are intended to be combined with weak lensing samples in order to produce precise cosmological constraints from the joint analysis of large-scale structure and lensing correlations. Two-point correlation functions are measured for a sample of 6.6×10^5 luminous red galaxies selected using the REDMAGIC algorithm over an area of 1321 square degrees, in the redshift range 0.15 0.5, b(σ_8/0.81)|_(z = 0.68) = 1.93±0.04 for L/L∗ > 1 and b(σ_8/0.81)|_(z = 0.83) = 1.98±0.07 for L/L∗ > 1.5, broadly consistent with expectations for the redshift and luminosity dependence of the bias of red galaxies. We show these measurements to be consistent with the linear bias obtained from tangential shear measurements

Systems, methods and computer program products for prediction of defect-related failures in integrated circuits

Systems, methods and computer program products for predicting defect-related failures in integrated circuits produced by an integrated circuit fabrication process identify objects in a circuit layout for the integrated circuit design, each object having a location in the circuit layout and a reliability connectivity in the integrated circuit design. Sample object defects are generated for the identified objects, each sample object defect representing a defect produced in an object by the integrated circuit fabrication process and having a defect magnitude associated therewith. An accelerated life defect influence model is identified for each sample object defect, relating the lifetime of an object to the defect magnitude of a defect in the object. Sample object lifetimes are generated from the defect magnitudes associated with the sample object defects according to the corresponding identified accelerated life defect influence models. A prediction of the reliability of integrated circuits is generated from the sample object lifetimes according to the reliability connectivity of the associated objects in the integrated circuit design. Preferably, the accelerated life defect influence models include log-linear regression models, which may include deterministic object lifetime functions, each relating the defect magnitude of the at least one sample object defect to one object lifetime value, and log-linear object lifetime distributions, each relating the defect magnitude of a sample object defect to a plurality of object lifetime values