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    Monte-Carlo generator for e+e- annihilation into lepton and hadron pairs with precise radiative corrections

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    Recently, various cross sections of e+e- annihilation into hadrons were accurately measured in the energy range from 0.37 to 1.39 GeV with the CMD-2 detector at the VEPP-2M collider. In the pi+pi- channel a systematic uncertainty of 0.6% has been achieved. A Monte-Carlo Generator Photon Jets (MCGPJ) was developed to simulate events of the Bhabha scattering as well as production of two charged pions, kaons and muons. Based on the formalism of Structure Functions, the leading logarithmic contributions related to the emission of photon jets in the collinear region are incorporated into the MC generator. Radiative corrections (RC) in the first order of alpha are accounted for exactly. The theoretical precision of the cross sections with RC is estimated to be better than 0.2%. Numerous tests of the program as well as comparison with other MC generators and CMD-2 experimental data are presented.Comment: LaTeX, 23 pages with 18 figure

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    Energy for Development: The Potential Role of Renewable Energy in Meeting the Millennium Development Goals

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    This report identifies renewable energy options that are currently in wide use in some regions and that are now ready for large-scale introduction in many areas of the developing world. Through 26 case studies, the report cites biogas, small hydro, solar, wind, ethanol, and biodiesel, among other technologies, as viable options for poverty alleviation in developing countries.As their cost has declined and their reliability has improved, renewable energy technologies have often emerged as more affordable and practical means of providing essential energy services. Although the strongest renewable energy growth has been in grid-connected power systems and liquid fuels for transportation, several technologies are well-suited to providing modern energy services for low-income people. Scaling up a broad portfolio of renewable energy options can make a major contribution to achieving the Millennium Development Goals, concludes the report.The creation of REN 21 was sponsored by the German Federal Ministry for Economic Cooperation and Development and the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety. Formally established in Copenhagen in June 2005, REN 21 is now supported by a steering committee of 11 governments, five intergovernmental organizations, five non-governmental organizations, and several regional, local and private organizations

    Power, norms and institutional change in the European Union: the protection of the free movement of goods

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    How do institutions of the European Union change? Using an institutionalist approach, this article highlights the interplay between power, cognitive limits, and the normative order that underpins institutional settings and assesses their impact upon the process of institutional change. Empirical evidence from recent attempts to reinforce the protection of the free movement of goods in the EU suggests that, under conditions of uncertainty, actors with ambiguous preferences assess attempts at institutional change on the basis of the historically defined normative order which holds a given institutional structure together. Hence, path dependent and incremental change occurs even when more ambitious and functionally superior proposals are on offer

    Some Unsteady Fluid Forces on Pump Impellers

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    Spectral analyses of all the forces and moments acting on a typical centrifugal pump impeller/volute combination are presented. These exhibit shaft frequencies, blade passing frequencies, and beat frequencies associated with a whirl motion imposed on the shaft in order to measure rotordynamic forces. Among other features the unsteady thrust was found to contain a surprisingly large blade passing harmonic. While previous studies have explored the magnitudes of the steady fluid-induced radial forces and the fluid-induced rotordynamic forces for this typical centrifugal pump impeller/volute combination, this paper presents information on the steady bending moments and rotordynamic moments due to the fluid flow. These imply certain axial locations for the lines of action of the radial and rotordynamic forces. Data on the lines of action are presented and allow inferences on the sources of the forces

    On the Unity of 'Number' in Semantics and Morphology

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    Mimicry - Sheep in wolves' clothing

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    Pedagogic issues in designing a module to include online assessment : a case study

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    This case study concerns 'Travel and Society', an advanced level module offered to students taking the Travel Management pathway at London Metropolitan University’s North Campus. It has been designed to introduce travel management students to the broad context of personal mobility. This module is unique, as for the first time it offers undergraduate students taking this pathway the opportunity to utilise Web-based assessment. At an employer's forum, the concept was praised by the employers present as a suitable and innovative way of assessing learning within the context of developing the student for the workplace
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