182 research outputs found

    Application of Large-Scale Synthetic Power System Models for Energy Economic Studies

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    Due to information confidentiality issues, there is limited access to actual power system models that represent features of actual power grids for teaching, training, and research purposes. The authors\u27 previous work describes the process of creating synthetic transmission networks, with statistics similar to those of actual power grids. Thus, this paper outlines a systematic methodology to augment the synthetic network base case for energy economic studies. The key step is to determine generator cost models by fuel type and capacity. Based on statistics summarized from the actual grids, two approaches are proposed to assign coefficients to generator cost models. To illustrate the proposed creation procedure, we describe the construction of a synthetic model for Electric Reliability Council of Texas footprint. Simulation results are presented to verify that the created test system is able to represent the behavior of actual power systems

    Rethinking globalised resistance : feminist activism and critical theorising in international relations

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    This article argues that a feminist approach to the 'politics of resistance' offers a number of important empirical insights which, in turn, open up lines of theoretical inquiry which critical theorists in IR would do well to explore. Concretely, we draw on our ongoing research into feminist 'anti-globalisation' activism to rethink the nature of the subject of the politics of resistance, the conditions under which resistance emerges and how resistance is enacted and expressed. We begin by discussing the relationship of feminism to critical IR theory as a way of situating and explaining the focus and approach of our research project. We then summarise our key empirical arguments regarding the emergence, structure, beliefs, identities and practices of feminist 'anti-globalisation' activism before exploring the implications of these for a renewed critical theoretical agenda in IR

    Meaningful engagement: computer-based interactive media art in public space.

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    Interactive technologies, including electronic devices are increasingly being utilized as a medium for artistic expression and have been placed in freely accessible public environments with mixed results. When audiences encounter computer-based interactive media arts in a public space they are drawn by various interactivities, to play and experiment with them. However, whether the audience is able to gain a meaningful experience through those physical interactivities has remained an issue of both theoretical and practical debate. This paper will focus on these aspects, most specifically through the study of interactive art in freely accessible public space. The author proposes four new conceptual/analytical tools for examining the subject. It is anticipated that this paper will provide possible alternative strategies for both artists and art researchers in this field with a purpose to enhance intellectual engagement with their audiences, so as to succeed in leading interactors to obtain meaningful experience and rewards

    Fuzzy Free Path Detection based on Dense Disparity Maps obtained from Stereo Cameras

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    In this paper we propose a fuzzy method to detect free paths in real-time using digital stereo images. It is based on looking for linear variations of depth in disparity maps, which are obtained by processing a pair of rectified images from two stereo cameras. By applying least-squares fitting over groups of disparity maps columns to a linear model, free paths are detected by giving a certainty using a fuzzy rule. Experimental results on real outdoor images are also presented.Nuria Ortigosa acknowledges the support of Universidad Polit'ecnica de Valencia under grant FPI-UPV 2008. Samuel Morillas acknowledges the support of Spanish Ministry of Education and Science under grant MTM 2009-12872-C02-01.Ortigosa Araque, N.; Morillas Gómez, S.; Peris Fajarnes, G.; Dunai Dunai, L. (2012). Fuzzy Free Path Detection based on Dense Disparity Maps obtained from Stereo Cameras. 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Journal of Intelligent and Robotic Systems, 48(4), 539-566. doi:10.1007/s10846-006-9125-6McFetridge, L., & Ibrahim, M. Y. (2009). A new methodology of mobile robot navigation: The agoraphilic algorithm. Robotics and Computer-Integrated Manufacturing, 25(3), 545-551. doi:10.1016/j.rcim.2008.01.008Sun, H., & Yang, J. (2001). Obstacle detection for mobile vehicle using neural network and fuzzy logic. Neural Network and Distributed Processing. doi:10.1117/12.441696Ortigosa, N., Morillas, S., & Peris-Fajarnés, G. (2010). Obstacle-Free Pathway Detection by Means of Depth Maps. Journal of Intelligent & Robotic Systems, 63(1), 115-129. doi:10.1007/s10846-010-9498-4Picton, P. D., & Capp, M. D. (2008). Relaying scene information to the blind via sound using cartoon depth maps. Image and Vision Computing, 26(4), 570-577. doi:10.1016/j.imavis.2007.07.005Zhang, Z. (2000). A flexible new technique for camera calibration. 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    Fuzzy Free Path Detection from Disparity Maps by Using Least-Squares Fitting to a Plane

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    A method to detect obstacle-free paths in real-time which works as part of a cognitive navigation aid system for visually impaired people is proposed. It is based on the analysis of disparity maps obtained from a stereo vision system which is carried by the blind user. The presented detection method consists of a fuzzy logic system that assigns a certainty to be part of a free path to each group of pixels, depending on the parameters of a planar-model fitting. We also present experimental results on different real outdoor scenarios showing that our method is the most reliable in the sense that it minimizes the false positives rate.N. Ortigosa acknowledges the support of Universidad Politecnica de Valencia under grant FPI-UPV 2008 and Spanish Ministry of Science and Innovation under grant MTM2010-15200. S. Morillas acknowledges the support of Universidad Politecnica de Valencia under grant PAID-05-12-SP20120696.Ortigosa Araque, N.; Morillas Gómez, S. (2014). 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    Revolutions from above: worker training as trasformismo in South Korea

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    While making very substantial changes to the population's working conditions, government strategies to foster economic development in South Korea have historically attempted to keep worker involvement, in terms of influence on the process, to a bare minimum. Applying the Gramscian concept of passive revolution, this article analyses governance mechanisms and production relations over a history of authoritarianism and up to the contemporary period of democratic reform. Trasformismo, which is a strategy of limited concessions, has been provided via vocational training for workers. Despite this attempt at inclusion, it is concluded that workers have not enjoyed full participation in negotiation for their welfare at any time in Korean history

    Universal Alcohol/Drug Screening in Prenatal Care: A Strategy for Reducing Racial Disparities? Questioning the Assumptions

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    Agencies and organizations promoting universal screening for alcohol and drug use in prenatal care argue that universal screening will reduce White versus Black racial disparities in reporting to Child Protective Services (CPS) at delivery. Yet, no published research has assessed the impact of universal screening on reporting disparities or explored plausible mechanisms. This review defines two potential mechanisms: Equitable Surveillance and Effective Treatment and identifies assumptions underlying each mechanism. It reviews published literature relating to each assumption. Research relating to assumptions underlying each mechanism is primarily inconclusive or contradictory. Thus, available research does not support the claim that universal screening for alcohol and drug use in prenatal care reduces racial disparities in CPS reporting at delivery. Reducing these reporting disparities requires more than universal screening

    A simple rule to determine which insolation cycles lead to interglacials

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    The pacing of glacial–interglacial cycles during the Quaternary period (the past 2.6 million years) is attributed to astronomically driven changes in high-latitude insolation. However, it has not been clear how astronomical forcing translates into the observed sequence of interglacials. Here we show that before one million years ago interglacials occurred when the energy related to summer insolation exceeded a simple threshold, about every 41,000 years. Over the past one million years, fewer of these insolation peaks resulted in deglaciation (that is, more insolation peaks were ‘skipped’), implying that the energy threshold for deglaciation had risen, which led to longer glacials. However, as a glacial lengthens, the energy needed for deglaciation decreases. A statistical model that combines these observations correctly predicts every complete deglaciation of the past million years and shows that the sequence of interglacials that has occurred is one of a small set of possibilities. The model accounts for the dominance of obliquity-paced glacial–interglacial cycles early in the Quaternary and for the change in their frequency about one million years ago. We propose that the appearance of larger ice sheets over the past million years was a consequence of an increase in the deglaciation threshold and in the number of skipped insolation peaks.P.C.T. acknowledges funding from a Leverhulme Trust Research Project Grant (RPG-2014-417). M.C. and T.M. acknowledge support from the Belgian Policy Office under contract BR/121/A2/STOCHCLIM. E.W.W. is funded under a Royal Society Research Professorship and M.C. is a senior research scientist with the Belgian National Fund of Scientific Research
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