998 resultados para Concept vector


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The Internet Corporation for Assigned Names and Numbers (ICANN) is an institution besieged. It has endeavored to be democratic but its attempts to do so have been disastrous. The typical explanation for this is that the problem is with ICANN: it fails to meet its democratic obligations. My view is that the problem is with our understanding of "democracy." Democracy is an empty concept that fails to describe few, if any, of our genuine political commitments. In the real world, the failings inherent in "democracy" have been papered over by some unusual characteristics of the physical political process. However, in online trans-national institutions like ICANN, democracy is exposed as a poor substitute for a number of other conceptions of our political commitments. This Article seeks to articulate these political commitments and to explain why democracy and ICANN are such a poor mix. It begins by charting the rise of ICANN and its attempts to be democratic. It then explains why democracy is an empty shell of a concept. It then explores some features of democracy and ICANN, explaining why the online world exposes limitations in implications of democracy such as the nature of the demos, the idea of constituencies, direct democracy, voting, and the like. It concludes that ICANN's example demonstrates that democracy is in fact anything but a coherent general theory of political action. We need to consider, then, whether we should continue to berate ICANN for its undemocratic actions.

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As Unmanned Aircraft Systems (UAS) grow in complexity, and their level of autonomy increases|moving away from the concept of a remotely piloted systems and more towards autonomous systems|there is a need to further improve reliability and tolerance to faults. The traditional way to accommodate actuator faults is by using standard control allocation techniques as part of the flight control system. The allocation problem in the presence of faults often requires adding constraints that quantify the maximum capacity of the actuators. This in turn requires on-line numerical optimisation. In this paper, we propose a framework for joint allocation and constrained control scheme via vector input scaling. The actuator configuration is used to map actuator constraints into the space of the aircraft generalised forces, which are the magnitudes demanded by the light controller. Then by constraining the output of controller, we ensure that the allocation function always receive feasible demands. With the proposed framework, the allocation problem does not require numerical optimisation, and since the controller handles the constraints, there is not need to implement heuristics to inform the controller about actuator saturation.

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Binary Ti vectors are the plasmid vectors of choice in Agrobacterium-mediated plant transformation protocols. The pGreen series of binary Ti vectors are configured for ease-of-use and to meet the demands of a wide range of transformation procedures for many plant species. This plasmid system allows any arrangement of selectable marker and reporter gene at the right and left T-DNA borders without compromising the choice of restriction sites for cloning, since the pGreen cloning sites are based on the well-known pBluescript general vector plasmids. Its size and copy number in Escherichia coli offers increased efficiencies in routine in vitro recombination procedures. pGreen can replicate in Agrobacterium only if another plasmid, pSoup, is co-resident in the same strain. pSoup provides replication functions in trans for pGreen. The removal of RepA and Mob functions has enabled the size of pGreen to be kept to a minimum. Versions of pGreen have been used to transform several plant species with the same efficiencies as other binary Ti vectors. Information on the pGreen plasmid system is supplemented by an Internet site (http://www.pgreen.ac.uk) through which comprehensive information, protocols, order forms and lists of different pGreen marker gene permutations can be found.

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Although integrated marketing communication (IMC) has progressed towards midrange maturity level, its full-scale adoption has been impeded by a lack of consensus on its defining constructs. The purpose of this study is to move from abstraction to define the construct of strategic integration (SI) and develop this into a management tool, thus making an important contribution to both the theory and practice of IMC. Drawing from both IMC and strategic management literature, the construct of SI is operationalised into a number of key factors and a well-cited management model, Fuchs’ ‘integration valuator’ is explored as the starting point of a measurement tool for IMC. To do this, a Delphi study invites the scrutiny of an expert panel of world-leading IMC researchers and practitioners. The panel validated the model construction process,redefined overarching constructs and key factors with a high degree of consensus, supported a process measure, suggested a weighted evaluation measure and recognised the importance of developing such a measure. They delivered clear and consistent imperatives guiding model development. The result is a measure of SI that evaluates organisational proficiency and diagnoses the integration of IMC campaigns. It also advances theory by providing a better understanding of the construct of SI.

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This study evaluated 4th-grade students' understanding of the concept of physical activity and assessed the effects of two interventions to enhance the students' understanding of this concept. Students were randomly assigned to 1 of 3 conditions: the video group (n = 40) watched a 5-min video describing physical activity; the verbal group (n = 42) listened to a generic description of physical activity; the control group received no instruction (n = 45). Students completed a 17-item checklist testing their understanding of the concept of physical activity. Compared to controls, students in the verbal and video group demonstrated significantly higher checklist scores, with the video group scoring significantly higher than the verbal group. Only 35.6% of the controls, compared to 52.4% and 70.0% of the verbal and video groups respectively, could classify greater than or equal to 15 of the checklist items correctly, The results indicate that, without intervention, children have a limited understanding of the concept of physical activity.

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Bit-stream-based control, which uses one bit wide signals to control power electronics applications, is a new approach for controller design in power electronic systems. This study presents a novel family of three-phase space vector modulators, which are based on the bit-stream technique and suitable for three-phase inverter systems. Each of the proposed modulators simultaneously converts a two-phase reference to the three-phase domain and reduces switching frequencies to reasonable levels. The modulators do not require carrier oscillators, trigonometric functions or, in some cases, sector detectors. A complete three-phase modulator can be implemented in as few as 102 logic elements. The performance of the proposed modulators is compared through simulation and experimental testing of a 6 kW, three-phase DC-to-AC inverter. Subject to limits on the modulation index, the proposed modulators deliver spread-spectrum output currents with total harmonic distortion comparable to a standard carrier-based space vector pulse width modulator.

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Given the level of debate and theorising in Western thought on the topic of justice, it is curious that the concept of injustice has not attracted the same attention. While many schools of thought have sought to address various injustices, most define injustice solely as the opposite of their vision of a just society – it seems they have not been interested in exploring injustice per se. With this as a starting point, Eric Heinze’s The Concept of Injustice addresses this oversight and, by taking injustice itself as an object of analysis, adds a new dimension to these discussions...

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This research proposed a new framework for safety culture and examined the influence that culture has on safety in the heavy vehicle industry. The results gave evidence for an industry wide culture, allowing future safety interventions to be designed in a culturally-relevant manner. Designing culturally-relevant interventions may maximise their effectiveness and reduce the levels of resistance to safety that have been evident in past years.

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The series expansion of the plasma fields and currents in vector spherical harmonics has been demonstrated to be an efficient technique for solution of nonlinear problems in spherically bounded plasmas. Using this technique, it is possible to describe the nonlinear plasma response to the rotating high-frequency magnetic field applied to the magnetically confined plasma sphere. The effect of the external magnetic field on the current drive and field configuration is studied. The results obtained are important for continuous current drive experiments in compact toruses. © 2000 American Institute of Physics.

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Toxicity is a major concern for anti-neoplastic drugs, with much of the existing pharmacopoeia being characterized by a very narrow therapeutic index. 'Network-targeted' combination therapy is a promising new concept in cancer therapy, whereby therapeutic index might be improved by targeting multiple nodes in a cell's signaling network, rather than a single node. Here, we examine the potential of this novel approach, illustrating how therapeutic benefit could be achieved with smaller doses of the necessary agents.

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This paper aims to review the notion of the one-stop shop, particularly as it has developed in Australia. It has three main components. The first focuses on a significant initiative taken by the Coombs Royal Commission on Australian Government Administration as a form of action research in the mid-1970s. The second highlights the associated work on access theory by the late Bernard Schaffer and his associates and explains why this work was of fundamental importance for the development of the idea of the one-stop shop. The third deals with subsequent Australian understandings and a pp lications of the idea.

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The generation of a correlation matrix for set of genomic sequences is a common requirement in many bioinformatics problems such as phylogenetic analysis. Each sequence may be millions of bases long and there may be thousands of such sequences which we wish to compare, so not all sequences may fit into main memory at the same time. Each sequence needs to be compared with every other sequence, so we will generally need to page some sequences in and out more than once. In order to minimize execution time we need to minimize this I/O. This paper develops an approach for faster and scalable computing of large-size correlation matrices through the maximal exploitation of available memory and reducing the number of I/O operations. The approach is scalable in the sense that the same algorithms can be executed on different computing platforms with different amounts of memory and can be applied to different bioinformatics problems with different correlation matrix sizes. The significant performance improvement of the approach over previous work is demonstrated through benchmark examples.

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Bit-Stream based control, which uses one bit wide signals to control power electronics applications, is a new approach for controller design in power electronic systems. Bit-Stream signals are inherently high frequency in nature, and as such some form of down sampling or modulating is essential to avoid excessive switching losses. This paper presents a novel three-phase space vector modulator, which is based on the Bit-Stream technique and suitable for standard three-phase inverter systems. The proposed modulator simultaneously converts a two phase reference to the three-phase domain and reduces switching frequencies to reasonable levels. The modulator consumes relatively few logic elements and does not require sector detectors, carrier oscillators or trigonometric functions. The performance of the modulator was evaluated using ModelSim. Results indicate that, subject to limits on the modulation index, the proposed modulator delivers a spread-spectrum output with total harmonic distortion comparable to standard space vector pulse width modulation techniques.

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Recent discussions of energy security and climate change have attracted significant attention to clean energy. We hypothesize that rising prices of conventional energy and/or placement of a price on carbon emissions would encourage investments in clean energy firms. The data from three clean energy indices show that oil prices and technology stock prices separately affect the stock prices of clean energy firms. However, the data fail to demonstrate a significant relationship between carbon prices and the stock prices of the firms.

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This article assesses the extent to which the recently formulated Chinese concept of “Responsible Protection” (RP) offers a valuable contribution to the normative debate over R2P’s third pillar following the controversy over military intervention in Libya. While RP draws heavily on previous proposals such as the original 2001 ICISS report and Brazil’s “Responsibility while Protecting” (RwP), by amalgamating and re-packaging these earlier ideas in a more restrictive form the initiative represents a new and distinctive interpretation of R2P. However, some aspects of RP are framed too narrowly to provide workable guidelines for determining the permissibility of military intervention for civilian protection purposes, and should therefore be clarified and refined. Nevertheless, the Chinese proposal remains significant because it offers important insights into Beijing’s current stance on R2P. More broadly, China’s RP and Brazil’s RwP initiatives illustrate the growing willingness of rising, non-Western powers to assert their own normative preferences on sovereignty, intervention and global governance.