Capacity Value of Wind Power

Power systems are planned such that they have adequate generation capacity to meet the load, according to a defined reliability target. The increase in the penetration of wind generation in recent years has led to a number of challenges for the planning and operation of power systems. A key metric for generation system adequacy is the capacity value of generation. The capacity value of a generator is the contribution that a given generator makes to generation system adequacy. The variable and stochastic nature of wind sets it apart from conventional energy sources. As a result, the modeling of wind generation in the same manner as conventional generation for capacity value calculations is inappropriate. In this paper a preferred method for calculation of the capacity value of wind is described and a discussion of the pertinent issues surrounding it is given. Approximate methods for the calculation are also described with their limitations highlighted. The outcome of recent wind capacity value analyses in Europe and North America, along with some new analysis, are highlighted with a discussion of relevant issues also given

Polariton propagation in weak confinement quantum wells

Exciton-polariton propagation in a quantum well, under centre-of-mass quantization, is computed by a variational self-consistent microscopic theory. The Wannier exciton envelope functions basis set is given by the simple analytical model of ref. [1], based on pure states of the centre-of-mass wave vector, free from fitting parameters and "ad hoc" (the so called additional boundary conditions-ABCs) assumptions. In the present paper, the former analytical model is implemented in order to reproduce the centre-of-mass quantization in a large range of quantum well thicknesses (5a_B < L < inf.). The role of the dynamical transition layer at the well/barrier interfaces is discussed at variance of the classical Pekar's dead-layer and ABCs. The Wannier exciton eigenstates are computed, and compared with various theoretical models with different degrees of accuracy. Exciton-polariton transmission spectra in large quantum wells (L>> a_B) are computed and compared with experimental results of Schneider et al.\cite{Schneider} in high quality GaAs samples. The sound agreement between theory and experiment allows to unambiguously assign the exciton-polariton dips of the transmission spectrum to the pure states of the Wannier exciton center-of-mass quantization.Comment: 15 pages, 15 figures; will appear in Phys.Rev.

Charting the reach and contribution of IMP literature in other disciplines: A bibliometric analysis

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordThe acknowledgement of a research tradition by other disciplines shows its contribution to the development of the broader body of scientific knowledge. This paper investigates the contribution of IMP (Industrial Marketing and Purchasing) research to broader research disciplines by analyzing how researchers within and beyond IMP have cited core IMP articles. First, through quantitative bibliometric analysis, the paper identifies the diffusion to other research disciplines. Thereafter, through qualitative analysis, the impact of the IMP perspective is captured to understand how strong these imprints are. The analyses show that IMP research has been noticed among a range of adjacent research disciplines. However, the use of IMP references has generally been rudimentary, and without a deeper understanding of the IMP ontology, meaning that IMP still has some “weak ties” to the other disciplines. Establishing IMP's contribution through enduring imprints would need further engagement with researchers from other research disciplines and publications in top journals. The paper contributes empirically with how the IMP perspective has spread beyond the IMP Group and theoretically by adding insight into how research ideas travel and transform to other disciplines

Die Wirtschaftsgruppen des verarbeitenden Gewerbes in Mecklenburg-Vorpommern und ihre Entwicklung 1991 bis Mitte 1993

Available from Bibliothek des Instituts fuer Weltwirtschaft, ZBW, Duesternbrook Weg 120, D-24105 Kiel C 188391 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman