the natural frequencies and mode shapes of pneumatic tires are predicted using a geometrically accurate, three-dimensional finite element modeling. tire rubber materials and cord layers are represented independently using “shell element” available in cosmos. the effects of some physical parameters such as the inflation pressure tread pattern, thickness of belts and ply angles to the natural fre...

We present our work on the halo evolution of sulfur, based on observations of the S I lines around 9220 Å for ten stars for which the S abundance was obtained previously from much weaker S I lines at 8694 Å. We cannot confirm the rise and the high [S/Fe] abundances for low [Fe/H], as claimed in the literature from analysis of the 8694 Å lines. The reasons for claims of an increase in [S/Fe] wit...

impulsive and convective frequencies are one of the most important subjects for evaluation of the seismic behavior of tanks. these two frequencies are defined by housner and used for obtaining rayleigh damping in time history analysis. aci 350 and nzsee standards have suggested some analytical solutions for finding convective and impulsive frequencies. these frequencies can also extract from mo...

Depending on the type of analysis, Finite Element(FE) models of different fidelity are necessary. Creating these models manually is a labor intensive task. This paper discusses a generic approach for generating FE models of different fidelity from a single reference FE model. These different fidelity models are created by sub-structuring and a multi-scale superposition technique. Efficiency of ...

[Fe-Fe]-hydrogenases are enzymes that reversibly catalyze the reaction of protons and electrons to molecular hydrogen, which occurs in anaerobic media. In living systems, [Fe-Fe]-hydrogenases are mostly used for H(2) production. The [Fe-Fe]-hydrogenase H-cluster is the active site, which contains two iron atoms. The latest theoretical investigations1,2 advocate that the structure of di-iron air...

Mechanisms for Fe(III) oxide reduction were investigated in Geothrix fermentans, a dissimilatory Fe(III)-reducing microorganism found within the Fe(III) reduction zone of subsurface environments. Culture filtrates of G. fermentans stimulated the reduction of poorly crystalline Fe(III) oxide by washed cell suspensions, suggesting that G. fermentans released one or more extracellular compounds th...

To overcome the complication of jetty pile design process, artificial neural networks (ANN) are adopted. To generate the training samples for training ANN, finite element (FE) analysis was performed 50 times for 50 different design cases. The trained ANN was verified with another FE analysis case and then used as a structural analyzer. The multilayer neural network (MBPNN) with two hidden layer...

Mineral dust supplied to remote ocean regions stimulates phytoplankton growth through delivery of micronutrients, notably iron (Fe). Although attention is usually paid to Fe (hydr)oxides as major sources of available Fe, Fe-bearing clay minerals are typically the dominant phase in mineral dust. The mineralogy and chemistry of clay minerals in dust particles, however, are largely unknown. We con...

A systematic study has been made on the effect of Fe substitution by means of resistivity, thermal conductivity, and Seebeck coefficient of the Mg1−xFexB2 superconductor involving 0%, 0.3%, 0.6%, 1.2%, and 3.0% Fe content. The superconducting transition has been found to be very sharp 0.2 K for a pristine sample and substitution of Fe results in the decrease of TC with the increase in the trans...

Sulfur abundances have been determined for ten stars to resolve a debate in the literature on the Galactic chemical evolution of sulfur in the halo phase of the Milky Way. Our analysis is based on observations of the S i lines at 9212.9, 9228.1, and 9237.5 Å for stars for which the S abundance was obtained previously from much weaker S i lines at 8694.0 and 8694.6 Å. In contrast to the previous...