A fully coupled fluid-structure interaction simulation of three-dimensional dynamic ductile fracture in a steel pipeline

Long running fractures in high-pressure pipelines transporting hazardous fluid are catastrophic events resulting in pipeline damage and posing safety and environmental risks. Therefore, the ductile fracture propagation control is an essential element of the pipeline design. In this study, a coupled fluid-structure interaction modelling is used to simulate the dynamic ductile fractures in steel pipelines. The proposed model couples a fluid dynamics model describing the pipeline decompression and the fracture mechanics of the deforming pipeline exposed to internal and back-fill pressures. To simulate the state of the flow in a rupturing pipeline, a compressible one-dimensional computational fluid dynamics model is applied, where the fluid properties are evaluated using a rigorous thermodynamic model. The ductile failure of the steel pipeline is described as an extension of the modified Bai-Wierzbicki model implemented in a finite element code. The proposed methodology has successfully been applied to simulate a full-scale pipeline burst test performed by British Gas Company, which involved rupture of a buried X70 steel pipeline, initially filled with rich natural gas at 11.6 MPa and −5 °C

Remarks on searching zones of interest in locally uniform scenes

For searching for objects of limited size in a scene by using geometrical features, we suggest to segment not the whole scene, but only fragments of it containing the objects themselves and their environment. We examine the formalization of the search problem in the scene of such fragments, called the zones of interest, and discuss the results of its solution. © 2011 Pleiades Publishing, Ltd

Search of regions of interest in objects showing signs of a spot on locally homogeneous scenes

It is suggested that while searching a scene for objects of known sizes by means of spectral and geometrical signs, instead of segmentation of the entire scene, only those fragments that contain the objects themselves and their surroundings be segmented. The formalization of a search query in the scene of such fragments, called regions of interest, is discussed, methods of its solution are suggested, and the results obtained are examined further. © 2012 Pleiades Publishing, Ltd

Forward observables at RHIC, the Tevatron run II and the LHC

We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude (rho parameter) for present and future pp and pbar p colliders, and on total cross sections for gamma p -> hadrons at cosmic-ray energies and for gamma gamma -> hadrons up to sqrt(s)=1 TeV. These predictions are based on a study of many possible analytic parametrisations and invoke the current hadronic dataset at t=0. The uncertainties on total cross sections, including the systematic theoretical errors, reach 1% at RHIC, 3% at the Tevatron, and 10% at the LHC, whereas those on the rho parameter are respectively 10%, 17%, and 26%.Comment: 11 pages, 2 figures, LaTeX, presented at the Second International "Cetraro" Workshop & NATO Advanced Research Workshop "Diffraction 2002", Alushta, Crimea, Ukraine, August 31 - September 6, 200

The Pomeron In Exclusive Vector Meson Production

An earlier developed model for vector meson photoproduction, based on a dipole Pomeron exchange, is extended to electroproduction. Universality of the non linear Pomeron trajectory is tested by fitting the model to ZEUS and H1 data as well as to CDF data on $\bar pp$ elastic scattering.Comment: 12 pages, 13 figure

Photoproduction of vector mesons in the Soft Dipole Pomeron model

Exclusive photoproduction of all vector mesons by real and virtual photons is considered in the Soft Dipole Pomeron model. It is emphasized that being the Pomeron in this model a double Regge pole with intercept equal to one, we are led to rising cross-sections but the unitarity bounds are not violated. It is shown that all available data for rho, omega, phi, J/psi and Upsilon in the region of energies 1.7 <= W <= 250 GeV and photon virtualities 0 <= Q^2 <= 35 GeV^2, including the differential cross-sections in the region of transfer momenta 0 <= |t| <= 1.6 GeV^2, are well described by the model.Comment: 17 pages, 19 figure

Elastic pppp and pˉp\bar pp scattering in the models of unitarized pomeron

Elastic scattering amplitudes dominated by the Pomeron singularity which obey the principal unitarity bounds at high energies are constructed and analyzed. Confronting the models of double and triple (at $t=0$) Pomeron pole (supplemented by some terms responsible for the low energy behaviour) with existing experimental data on $pp$ and $\bar pp$ total and differential cross sections at $\sqrt{s}\geq 5$ GeV and $|t|\leq 6$ GeV$^{2}$ we are able to tune the form of the Pomeron singularity. Actually the good agreement with those data is received for both models though the behaviour given by the dipole model is more preferable in some aspects. The predictions made for the LHC energy values display, however, the quite noticeable difference between the predictions of models at $t\approx -0.4$ GeV$^{2}$. Apparently the future results of TOTEM will be more conclusive to make a true choice.Comment: Revtex4, 8 pages, 5 figures. Text is improved, no changes in figures and conclusions. Version to be published in Phys. Rev.

Contribution to the knowledge of Teloganodidae (Ephemeroptera, Ephemerelloidea) of India.

Two new species of Dudgeodes Sartori, 2008 and a new species of Teloganodes Eaton, 1882 are described from India; they are Dudgeodesselvakumari Martynov &amp; Palatov, sp. nov. from Himalayan region (Uttarakhand), Dudgeodesmolinerii Sivaruban, Martynov, Srinivasan, Barathy &amp; Isack, sp. nov., and Teloganodesbarathyae Sivaruban, Martynov, Srinivasan &amp; Isack, sp. nov. from the Tamil Nadu part of the Western Ghats. Thus, for now, the Teloganodidae fauna of India includes 11 species. Dudgeodesselvakumari sp. nov. appears to be significantly extend northward the known distribution of Dudgeodes. Partial COI sequences were used as an initial clustering method to show the relationships of D.selvakumari sp. nov. with other sequenced operational taxonomic units (OTU) of the genus

Neuroprotective effects of the novel ethylthiadiazole derivatives (LHT 4-15) in male rats

The study was performed on male rats of the Wistar line. The animals were simulated with total cerebral ischemia with preliminary administration of LHT 4-15 compounds in doses of 25 and 50 mg/kg for 60 min. The data obtained from the neurological deficit and in the behavioral tests of the experimental groups confirm the theory of the presence of ethylthiadiazole derivatives under the LHT code 4–15 neuroprotective properti