Конкурентоспроможність машинобудівних підприємств на ринку залізничного рухомого складу

Охарактеризовано распределение производственных мощностей и потребителей вагоно-строительной продукции на экономических рынках СНГ. Дана оценка конкурентной среды в подотрасли машиностроения железнодорожного подвижного состава на макро и микроуровне, выявлены факторы риска и обоснованы мероприятия, ориентированные на укрепление конкурентоспособности исследуемых предприятий. Ключевые слова: машиностроительное предприятие, конкурентоспособность, рынок, железнодорожный подвижной состав.Охарактеризовано розподіл виробничих потужностей і споживачів вагонобудівної продукції на економічних ринках СНД. Наведено оцінку конкурентного середовища в підгалузі маши-нобудування залізничного рухомого складу на макро і мікрорівні, виявлено фактори ризику й обґрунтовано заходи, орієнтовані на зміцнення конкурентоспроможності досліджуваних підприємств. Ключові слова: машинобудівне підприємство, конкурентоспроможність, ринок, залізничний рухомий склад.The paper characterizes production capacities and consumers of wagon products on the economic markets of CIS countries. The competition environment in the sector of railway rolling stock building on macro and micro-level was assessed, the factors of risk were identified, and measures oriented to streng-thening the competitiveness of the enterprises under investigation are well-grounded. Keywords: machine-building enterprise, competitiveness, market, railway rolling stock

Dependence of late glacial sea-level predictions on 3D Earth structure

Glacial isostatic adjustment is dominated by Earth rheology resulting in a variability of relative sea-level (RSL) predictions of more than 100 meters during the last glacial cycle. Seismic tomography models reveal significant lateral variations in seismic wavespeed, most likely corresponding to variations in temperature and hence viscosity. Therefore, the replacement of 1D Earth structures by a 3D Earth structure is an essential part of recent research to reveal the impact of lateral viscosity contrasts and to achieve a more consistent view on solid-Earth dynamics. Here, we apply the VIscoelastic Lithosphere and MAntle model VILMA to predict RSL during the last deglaciation. We create an ensemble of geodynamically constrained 3D Earth structures which is based on seismic tomography models while considering a range of conversion factors to transfer seismic velocity variations into viscosity variations. For a number of globally distributed sites, we discuss the resulting variability in RSL predictions, compare this with regionally optimized 1D Earth structures, and validate the model results with relative sea-level data (sea-level indicators). This study is part of the German Climate Modeling initiative PalMod aiming the modeling of the last glacial cycle under consideration of a coupled Earth system model, i.e. including feedbacks between ice-sheets and the solid Earth

How to erase surface plasmon fringes

We report the realization of a dual surface plasmon polariton (SPP) microscope based on leakage radiation (LR) analysis. The microscope can either image SPP propagation in the direct space or tin the Fourier space. This particularity allows in turn manipulation of the LR image for a clear separation of different interfering SPP contributions present close to optical nanoelements.Comment: Appl. Phys. Lett. 89, 091117 (2006

Global plate motion frames: Toward a unified model

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94772/1/rog1664.pd

Subduction and continental collision in the Eastern Mediterranean during the closure of the Tethyan gateway

Plate tectonics and mantle dynamics controlled the continental collision and tectonics of the Eastern Mediterranean – Tethyan realm, including by closing the Tethys Seaway linking the Atlantic and Indo-Pacific oceans. This led to reorganizations in ocean circulation, diversification and migration of marine and terrestrial species, and climatic change. Here, I review some of the work on the geodynamics of the region, including on the evolution of topography, and how paleotopography was influenced by mantle convection and volcanism. Mantle convection appears to have had a significant impact on the paleoenvironment, including by ultimately establishing the Gomphotherium Landbridge in the Miocene, enabling greater faunal exchanges between Africa-Arabia and Eurasia

Implications of a nonlinear ⁴⁰Ar/³⁹Ar age progression along the Louisville seamount trail for models of fixed and moving hot spots

The Louisville seamount trail has been recognized as one of the key examples of hot spot volcanism, comparable to the classic volcanic Hawaiian-Emperor lineaments. The published total fusion ⁴⁰Ar/³⁹Ar data of Watts et al. [1988] showed an astonishing linear age progression, firmly establishing Louisville as a fixed hot spot in the South Pacific mantle. We report new 40Ar/39Ar ages based on high-resolution incremental heating 40Ar/39Ar dating for the same group of samples, showing a marked increase in both precision and accuracy. One of the key findings in our reexamination is that the age progression is not linear after all. The new data show a significantly decreased ‘‘apparent’’ plate velocity for the Louisville seamount trail older than 62 Ma but confirm the linear trend between 47 Ma and the present day (although based on only three samples over 2150 km). The most recent volcanic activity in the Louisville seamount trail has now been dated at 1.11 ± 0.04 Ma for the most southeastern seamount located at 50°26’S and 139°09’W. These results indicate that the Louisville age progression should be interpreted on the basis of both plate and hot spot motion. In this paper we examine our new results in conjunction with the numerical mantle flow models of Steinberger et al. [2004] that also predict marked deviations from simple linear age progressions. With these models we can achieve a good fit to the geometry of both the Hawaiian and Louisville seamount trails and their age progressions as well as the ~15° paleolatitudinal shift observed by Tarduno et al. [2003] for the Hawaiian hot spot between 80 and 47 Ma. If the model is restricted to Pacific hot spots only, we can improve the fit to the nonlinear age trend for the Louisville seamount trail by allowing an additional rotation change of the Pacific plate around 62 Ma and by decreasing the initiation age of the Louisville plume from 120 to 90 Ma. This improved model features a significant eastward hot spot motion of ~5° between 80 and 30 Ma for the Louisville hot spot, which is quite dissimilar to the southward motion of the Hawaiian hot spot during the same time interval, followed by a minor ~2° latitudinal shift over the last 30 Myr. If hot spot tracks are considered globally, the age trend observed for the oldest part of the Louisville seamount trail does not entirely follow the numerical model predictions. This may indicate some remaining inaccuracies in the global plate circuit, but it may also indicate that the Louisville hot spot experienced a motion somewhat different than in the numerical model: faster in the interval between 62 and 47 Ma but slower before that.Copyrighted by American Geophysical Union.Keywords: hot spots, seamounts, ⁴⁰Ar/³⁹Ar geochronology, submarine alteration, guyots, Pacific plat

Effects of upper mantle heterogeneities on the lithospheric stress field and dynamic topography

The orientation and tectonic regime of the observed crustal/lithospheric stress field contribute to our knowledge of different deformation processes occurring within the Earth's crust and lithosphere. In this study, we analyze the influence of the thermal and density structure of the upper mantle on the lithospheric stress field and topography. We use a 3-D lithosphere–asthenosphere numerical model with power-law rheology, coupled to a spectral mantle flow code at 300 km depth. Our results are validated against the World Stress Map 2016 (WSM2016) and the observation-based residual topography. We derive the upper mantle thermal structure from either a heat flow model combined with a seafloor age model (TM1) or a global S-wave velocity model (TM2). We show that lateral density heterogeneities in the upper 300 km have a limited influence on the modeled horizontal stress field as opposed to the resulting dynamic topography that appears more sensitive to such heterogeneities. The modeled stress field directions, using only the mantle heterogeneities below 300 km, are not perturbed much when the effects of lithosphere and crust above 300 km are added. In contrast, modeled stress magnitudes and dynamic topography are to a greater extent controlled by the upper mantle density structure. After correction for the chemical depletion of continents, the TM2 model leads to a much better fit with the observed residual topography giving a good correlation of 0.51 in continents, but this correction leads to no significant improvement of the fit between the WSM2016 and the resulting lithosphere stresses. In continental regions with abundant heat flow data, TM1 results in relatively small angular misfits. For example, in western Europe the misfit between the modeled and observation-based stress is 18.3°. Our findings emphasize that the relative contributions coming from shallow and deep mantle dynamic forces are quite different for the lithospheric stress field and dynamic topography

Fast volume reconstruction from motion corrupted stacks of 2D slices

Capturing an enclosing volume of moving subjects and organs using fast individual image slice acquisition has shown promise in dealing with motion artefacts. Motion between slice acquisitions results in spatial inconsistencies that can be resolved by slice-to-volume reconstruction (SVR) methods to provide high quality 3D image data. Existing algorithms are, however, typically very slow, specialised to specific applications and rely on approximations, which impedes their potential clinical use. In this paper, we present a fast multi-GPU accelerated framework for slice-to-volume reconstruction. It is based on optimised 2D/3D registration, super-resolution with automatic outlier rejection and an additional (optional) intensity bias correction. We introduce a novel and fully automatic procedure for selecting the image stack with least motion to serve as an initial registration target. We evaluate the proposed method using artificial motion corrupted phantom data as well as clinical data, including tracked freehand ultrasound of the liver and fetal Magnetic Resonance Imaging. We achieve speed-up factors greater than 30 compared to a single CPU system and greater than 10 compared to currently available state-of-the-art multi-core CPU methods. We ensure high reconstruction accuracy by exact computation of the point-spread function for every input data point, which has not previously been possible due to computational limitations. Our framework and its implementation is scalable for available computational infrastructures and tests show a speed-up factor of 1.70 for each additional GPU. This paves the way for the online application of image based reconstruction methods during clinical examinations. The source code for the proposed approach is publicly available

Continental crust beneath southeast Iceland

The magmatic activity (0–16 Ma) in Iceland is linked to a deep mantle plume that has been active for the past 62 My. Icelandic and northeast Atlantic basalts contain variable proportions of two enriched components, interpreted as recycled oceanic crust supplied by the plume, and subcontinental lithospheric mantle derived from the nearby continental margins. A restricted area in southeast Iceland—and especially the Öræfajökull volcano—is characterized by a unique enriched-mantle component (EM2-like) with elevated 87Sr/86Sr and 207Pb/204Pb. Here, we demonstrate through modeling of Sr–Nd–Pb abundances and isotope ratios that the primitive Öræfajökull melts could have assimilated 2–6% of underlying continental crust before differentiating to more evolved melts. From inversion of gravity anomaly data (crustal thickness), analysis of regional magnetic data, and plate reconstructions, we propose that continental crust beneath southeast Iceland is part of ∼350-km-long and 70-km-wide extension of the Jan Mayen Microcontinent (JMM). The extended JMM was marginal to East Greenland but detached in the Early Eocene (between 52 and 47 Mya); by the Oligocene (27 Mya), all parts of the JMM permanently became part of the Eurasian plate following a westward ridge jump in the direction of the Iceland plume