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The attacks of September 11, 2001 spurred an intense interest in “moderate Islam” in U.S. government circles. Some high-ranking officials, for example, saw “moderate Muslims” as necessary allies in the “War on Terror.” In this article, we examine how the United States went about making allies in the Muslim world after the attacks. The goal was supposedly straightforward: “moderate” Muslims were to be strengthened and empowered to act as an antidote to radical groups. Yet such plans ran into numerous problems. First was the notoriously difficult definition of “moderate Islam,” which ranged from a simple rejection of the primacy of jihad to the acceptance of basic democratic values. Second, in reaching out to the Muslim world, the United States could not solve its own dilemma of being torn between a preference for stability provided by autocrats and the commitment to promote “Islamic” forms of democracy. These tensions resurfaced in the deepened partnership with two countries that were touted as manifestations of moderate Islam’s new promise: Turkey and Pakistan. Given their past efforts in fighting communism, both countries were seen to be potentially equally reliable partners in fighting the new “radical Islamic menace.” As we show, however, these visions did not materialize as hoped. The U.S. government overestimated the room local actors had to maneuver while underestimating the political costs that came with being tied too closely to American interests.

The power density of Modular Multilevel Converters (MMCs) is often limited by the over-dimensioning of the module capacitance value. This is common because with conventional control schemes, large voltage and energy margins must be included in the MMC design to avoid overvoltages in the module capacitors and saturation effects due to undervoltages in the module capacitors. This paper presents two Model Predictive Control methods that can reduce the necessary voltage and energy margins to a minimum and therefore increase the power density of the MMC system compared to conventionally controlled MMCs. A trade-off between computational effort and module capacitance over-dimensioning is discovered for the proposed constrained MPC. The unconstrained MPC is compared to the constrained MPC and conventional PI control using simulations. Finally, the performance of the unconstrained MPC is experimentally verified with an MMC system prototype and compared to a traditional PI control system., e & i Elektrotechnik und Informationstechnik, 140 (1), ISSN:0932-383X, ISSN:1613-7620

The optical emission of plasma on industrial steel samples induced by Laser Ablation-Spark Discharge-Optical Emission Spectroscopy (LA-SD-OES) and by Laser-Induced Breakdown Spectroscopy (LIBS) is investigated and correlated to the volume of ablated steel material. The 36 steel samples investigated have an iron content C(Fe) above 94 wt%. The excitation energy in LIBS (laser pulse of 55 mJ) and in LA-SD-OES (laser pulse of 5 mJ and spark discharge of 50 mJ) is the same. In LA-SD-OES, the optical emission of plasma and the size of ablation craters are very similar for all samples and a linear calibration curve for Mn is measured (R2 = 0.99). In LIBS, however, a pronounced dependence of the plasma emission and of the crater volume on the steel matrix is observed and calibration curves show a strong cross-sensitivity to other elements such as Si (matrix effect). The hardness, grain size, and phase of steel samples are analyzed to correlate the matrix effect in LIBS measurements to a physical property of the specimen. The different behavior for LA-SD-OES and LIBS is probably due to different processes of sampling and plasma excitation. From our results we conclude that LA-SD-OES enables for the element analysis of industrial steel largely independent of composition and structure of samples while in LIBS the matrix effect has to be taken into account. Version of record