1,039 research outputs found

    The Study of Realities and Prospects of Interaction of Ukraine with European Financial Organizations in the Conditions of Integration Processes

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    In the article were analyzed the prospects of cooperation between Ukraine and EU structural funds. There was studied the current state of interaction between Ukraine and EIB and EBRD, offered the directions of its optimization. It was proved, that the base of increase of effectiveness of the use of investment resources of European financial organizations by Ukraine and approach of prospects of widening of the credit projects spectrum is not only the clear regulation of the national strategy of economic development but also the improvement of the system of monitoring of the use of investment resources

    Relativistic Poynting Jets from Accretion Disks

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    A model is developed for relativistic Poynting jets from the inner region of a disk around a rotating black hole. The disk is initially threaded by a dipole-like magnetic field. The model is derived from the special relativistic equation for a force-free electromagnetic field. The ``head'' of the Poynting jet is found to propagate outward with a velocity which may be relativistic. The Lorentz factor of the head (Gamma) is found to be dependent on the magnetic field strength close to the black hole, B_0, the density of the external medium n_ext, and on the ratio R=r_0/r_g >1, where r_g is the gravitational radius of the black hole, and r_0 is the radius of the O-point of the initial dipole field threading the disk. For conditions pertinent to an active galactic nuclei, Gamma is approximately equal to 8 (10/R)^(1/3) (B_0/10^3 Gauss)^(1/3) (1/cm^3/n_ext)^(1/6). This model offers an explanation for the observed Lorentz factors which are of the order of 10 for the parsec-scale radio jets measured with very long baseline interferometry.Comment: 4 pages, 1 figur

    Relativistic Jets from Accretion Disks

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    The jets observed to emanate from many compact accreting objects may arise from the twisting of a magnetic field threading a differentially rotating accretion disk which acts to magnetically extract angular momentum and energy from the disk. Two main regimes have been discussed, hydromagnetic jets, which have a significant mass flux and have energy and angular momentum carried by both matter and electromagnetic field and, Poynting jets, where the mass flux is small and energy and angular momentum are carried predominantly by the electromagnetic field. Here, we describe recent theoretical work on the formation of relativistic Poynting jets from magnetized accretion disks. Further, we describe new relativistic, fully-electromagnetic, particle-in-cell simulations of the formation of jets from accretion disks. Analog Z-pinch experiments may help to understand the origin of astrophysical jets.Comment: 7 pages, 3 figures, Proc. of High Energy Density Astrophysics Conf., 200

    Sewer inspection and comparison of acoustic and CCTV methods

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    In the UK, the majority of sewer pipe inspections are carried out using closed-circuit television (CCTV) technology. This inspection technology is expensive; given the size of the UK sewer network, this means that only a small sample of network is inspected regularly. Up-to-date condition information on individual sewers is required to minimise sewer network operation failures and, ultimately, to eliminate flooding. There is therefore a need for a quicker and cheaper inspection method. This paper reports on a novel low-cost acoustic sensor system that can be used for the rapid detection of various defects in sewer pipes. It is shown that a large number of pipe defects can be classified and validated against CCTV images by way of visual examination of the acoustical data presented in the form of spectrograms. An overview of the technological principles used by the acoustic inspection method is presented in this paper together with the results of field trial surveys. The new method was tested in operational sewers in Austria and the acoustic inspection results compared with available CCTV reports: 79% of the defects identified by CCTV were also detected using the acoustic technique

    Russian approaches to energy security and climate change: Russian gas exports to the EU

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    The proposition that EU climate policy represents a threat to Russia’s gas exports to the EU, and therefore to Russia’s energy security, is critically examined. It is concluded that whilst the greater significance of climate-change action for Russian energy security currently lies not in Russia’s own emissions reduction commitments but in those of the EU, an even greater threat to Russia’s energy security is posed by the development of the EU internal gas market and challenges to Russia’s participation in that market. However, the coming decades could see Russia’s energy security increasingly influenced by climate-change action policies undertaken by current importers of Russian gas such as the EU, and potential importers such as China and India. The challenge for Russia will be to adapt to developments in energy security and climate-change action at the European and global levels

    Packing of concave polyhedra with continuous rotations using nonlinear optimisation

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    We study the problem of packing a given collection of arbitrary, in general concave, polyhedra into a cuboid of minimal volume. Continuous rotations and translations of polyhedra are allowed. In addition, minimal allowable distances between polyhedra are taken into account. We derive an exact mathematical model using adjusted radical free quasi phi-functions for concave polyhedra to describe non-overlapping and distance constraints. The model is a nonlinear programming formulation. We develop an efficient solution algorithm, which employs a fast starting point algorithm and a new compaction procedure. The procedure reduces our problem to a sequence of nonlinear programming subproblems of considerably smaller dimension and a smaller number of nonlinear inequalities. The benefit of this approach is borne out by the computational results, which include a comparison with previously published instances and new instances

    Dialogical organics of pedagogical discourse: linguo-pragmatic aspect

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    The article discusses the basic dialogue properties; it is particularly emphasized that the problems of studying the text, discourse and language of the operationalterminological apparatus are connected with the discursive concept of dialogis

    Research of antibodies to the acetylcholine receptors in patients with myasthenia gravis

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    Myasthenia is a chronic autoimmune neuromuscular disease. Antibodies to acetylcholine receptors are found in 85-90 % of patients with generalized myasthenia and play an important role in the pathogenesis of the disease. In the article compared comparison of the level of antibodies to the acetylcholine receptors (AChR) in patients with myasthenia gravis with the severity and duration of disease, age of onset, changes in the thymus and. treatment was realized. We examined. 80 patients. The research of antibodies was conducted by immune-enzymatic method. The highest levels of antibodies to AChR were detected in the group of patients who received long-term cytotoxic agents due to the steady progress of the disease. High. level of antibodies to AChR was observed in patients with predominance of weakness in craniobulbar muscles in clinical presentation. There were no correlations of level of antibodies to AChR with sex, duration of disease, presence of thymoma

    Optimal clustering of a pair of irregular objects

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    Cutting and packing problems arise in many fields of applications and theory. When dealing with irregular objects, an important subproblem is the identification of the optimal clustering of two objects. Within this paper we consider a container (rectangle, circle, convex polygon) of variable sizes and two irregular objects bounded by circular arcs and/or line segments, that can be continuously translated and rotated. In addition minimal allowable distances between objects and between each object and the frontier of a container, may be imposed. The objects should be arranged within a container such that a given objective will reach its minimal value. We consider a polynomial function as the objective, which depends on the variable parameters associated with the objects and the container. The paper presents a universal mathematical model and a solution strategy which are based on the concept of phi-functions and provide new benchmark instances of finding the containing region that has either minimal area, perimeter or homothetic coefficient of a given container, as well as finding the convex polygonal hull (or its approximation) of a pair of objects
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