12,043 research outputs found

    Competition on European energy markets: between policy ambitions and practical restrictions

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    This Document describes the background and the rationale of the European Union for pursuing liberalised energy markets, explains why this policy goal is not achieved yet, and discusses recent developments and some of the future challenges faced by political decision makers. Read also the accompanying press release .Five years after launching the process of electricity liberalisation, dominance of large utilities, lack of international transmission capacity, and national energy policies hinder the creation of competitive energy markets in Europe. Consequently, the expected downward convergence of electricity prices for EU business and EU consumers has only partly been realised. Established utility companies still have a strong position on some national electricity markets. By means of (inter)national mergers, they increase their market shares at the European level. As a consequence, the price of electricity remains at a higher level than the costs of generating the electricity. In addition, producers lack strong incentives to decrease costs and to develop new techniques of generation owing to missing fierce competitive market forces. The document shows that liberalising electricity markets increases competition provided that adequate institutional arrangements have been made. This requires, in general terms, combating dominant positions of producers by splitting up large established utility companies and implementing adequate surveillance on mergers, increasing capacities of interconnectors among the several member states, establishing spot markets at an international level, and encouraging encouraging transparency of national policies regarding production, transmission and trade.

    Drift and Forbush decreases

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    Evidence is presented that the drift effect on the modulation of galactic cosmic rays can be seen on Forbush decreases observed by the Deep River and Hermanus neutron monitors

    Detecting gravitational lensing cosmic shear from samples of several galaxies using two-dimensional spectral imaging

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    Studies of weak gravitational lensing by large-scale structures require the measurement of the distortions introduced to the shapes of distant galaxies at the few percent level by anisotropic light deflection along the line of sight. To detect this signal on 1-10 arcmin scales in a particular field, accurate measurements of the correlations between the shapes of order 1000-10000 galaxies are required. This large-scale averaging is required to accommodate the unknown intrinsic shapes of the background galaxies, even with careful removal of systematic effects. Here an alternative is discussed. If it is possible to measure accurately the detailed dynamical structure of the background galaxies, in particular rotating disks, then it should be possible to measure directly the cosmic shear distortion, as it generally leads to a non-self-consistent rotation curve. Narrow spectral lines and excellent two-dimensional spatial resolution are required. The ideal lines and telescope are CO rotational transitions and the Atacama Large Millimeter Array (ALMA) respectively.Comment: 12 pages, 4 figures, Expected to appear in ApJ Letters Vol. 570, 10 May 2002. Replaced with final proof version correcting minor typo

    Entrepreneurship Education in Iranian Higher Education: The Current State and Challenges

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    Entrepreneurship has long been considered a significant factor for socioeconomic growth and development because it provides millions of job opportunities, offers a variety of consumer goods and services, and generally increases national prosperity and competitiveness. Due to this positive impact of entrepreneurship, recent decades have seen a tremendous rise in entrepreneurship education at various universities and colleges around the globe, including in Iran. In the middle of this expansion remains the challenges and problems of development and changes for entrepreneurship.This paper investigates the state, trends, challenges and solutions in entrepreneurship education in Iran which emerged from an extensive review of literature. The literature reviewed indicates that entrepreneurship education in Iranian higher education faces with economic, political, social, and cultural challenges. Also this article offers some approaches and recommendations for resolving the challenges as well as encouraging and fostering entrepreneurship in higher education. The findings of this study provide valuable insights for policy makers, educators, students and graduate entrepreneurs. Stakeholders could use this study to make better choices in relation to the improvement of entrepreneurship education in Iranian higher education system

    Getting grip on complex water issues? : a case study: Rotterdam Mainport, Appropriate Assessment Wadden Sea

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    In Dutch water systems many human interventions are carried out. These interventions are designed to achieve management goals, like increase protection against flooding, improve environmental quality and/or stimulate the national economy. Decision-makers involved in these kinds of plans have to deal with ecological effects, physical effects, economic costs and benefits and technical feasibility. Furthermore, they operate within a complex web of interactions between policy, regulations, and social and political processes. This PhD-project aims at assisting decision-makers in constructing assessments of the impact of future human interventions in water systems

    Optimization of a charge-state analyzer for ECRIS beams

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    A detailed experimental and simulation study of the extraction of a 24 keV He-ion beam from an ECR ion source and the subsequent beam transport through an analyzing magnet is presented. We find that such a slow ion beam is very sensitive to space-charge forces, but also that the neutralization of the beam's space charge by secondary electrons is virtually complete for beam currents up to at least 0.5 mA. The beam emittance directly behind the extraction system is 65 pi mm mrad and is determined by the fact that the ion beam is extracted in the strong magnetic fringe field of the ion source. The relatively large emittance of the beam and its non-paraxiality lead, in combination with a relatively small magnet gap, to significant beam losses and a five-fold increase of the effective beam emittance during its transport through the analyzing magnet. The calculated beam profile and phase-space distributions in the image plane of the analyzing magnet agree well with measurements. The kinematic and magnet aberrations have been studied using the calculated second-order transfer map of the analyzing magnet, with which we can reproduce the phase-space distributions of the ion beam behind the analyzing magnet. Using the transfer map and trajectory calculations we have worked out an aberration compensation scheme based on the addition of compensating hexapole components to the main dipole field by modifying the shape of the poles. The simulations predict that by compensating the kinematic and geometric aberrations in this way and enlarging the pole gap the overall beam transport efficiency can be increased from 16 to 45%

    Influence of a mutltistrand cable design on its quench development process and stability

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    The quench development process was studied with two six-strand superconducting cable samples with insulated strands and different cabling design. One sample was the traditional ‘six-around-one’ cable, the other was of the ‘round-braid’ type. Quench was initiated by a heating pulse applied to a single strand. A significant difference was observed in the current redistribution among strands due to the different cabling designs. It has an important influence on the stability of multistrand cables. A new concept of the ‘single-strand stability’ was proposed and corresponding stability criteria were offered. A possible way to improve cable stability by using special cabling design is discussed

    An Anti-C1s Monoclonal, TNT003, Inhibits Complement Activation Induced by Antibodies Against HLA.

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    Antibody-mediated rejection (AMR) of solid organ transplants (SOT) is characterized by damage triggered by donor-specific antibodies (DSA) binding donor Class I and II HLA (HLA-I and HLA-II) expressed on endothelial cells. While F(ab')2 portions of DSA cause cellular activation and proliferation, Fc regions activate the classical complement cascade, resulting in complement deposition and leukocyte recruitment, both hallmark features of AMR. We characterized the ability of an anti-C1s monoclonal antibody, TNT003, to inhibit HLA antibody (HLA-Ab)-induced complement activation. Complement deposition induced by HLA-Ab was evaluated using novel cell- and bead-based assays. Human aortic endothelial cells (HAEC) were cultured with HLA-Ab and human complement; production of activated complement proteins was measured by flow cytometry. Additionally, C3d deposition was measured on single antigen beads (SAB) mixed with HLA-Ab and human complement. TNT003 inhibited HLA-Ab mediated complement deposition on HAEC in a concentration-dependent manner; C3a, C4a and C5a anaphylatoxin production was also diminished by TNT003. Finally, TNT003 blocked C3d deposition induced by Class I (HLAI-Ab)- and Class II (HLAII-Ab)-specific antibodies on SAB. These data suggest TNT003 may be useful for modulating the effects of DSA, as TNT003 inhibits complement deposition and split product formation generated by HLA-I/II-Ab in vitro
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