1,782 research outputs found
Effect of Beam Dynamics Processes in the Low Energy Ring ThomX
As part of the R\&D for the 50 MeV ThomX Compton source project, we have
studied the effect of several beam dynamics processes on the evolution of the
beam in the ring. The processes studied include among others Compton
scattering, intrabeam scattering, coherent synchrotron radiation. We have
performed extensive simulations of a full injection/extraction cycle (400000
turns). We show how each of these processes degrades the flux of photons
produced and how a feedback system contributes to recovering most of the flux.Comment: Submitted to IPAC'14, WEPRO00
On the non-paraxial modes of two-dimensional nearly concentric resonators
to be published in Applied OpticsA non-paraxial scalar diffraction integral is used to determine numerically the resonance modes of a two dimensional nearly concentric Fabry-Perot resonator. Numerical examples are provided and results are compared to those published by Laabs and Friberg [IEEE J. Quant. El., vol. 35, pp. 198-207, 1999]. Discrepancies are reported and further discussed on the basis of the difference between the solution space supported by the numerical method used in the present work and the one used by Laabs and Friberg
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Digital transforming capability and performance: a microfoundational perspective
PurposeDrawing on the literature on dynamic capabilities and digital transformation, this paper conceptualises and investigates the relevant antecedents of an essential capability for digital transformation â the digital transforming capability â and its effect on the competitive advantage of firms.Design/methodology/approachA framework with individual and organisational microfoundations of the digital transforming capability is proposed based on previous research. The digital transforming capability is conceptualised as a second-order construct. The model is tested using data from a broad spectrum of large US companies. Structural equation modelling (SEM) is applied to test the proposed framework.FindingsThe study identifies three main microfoundations that, when combined, build a digital transforming capability (digital-savvy skills, digital intensity and context for action and interaction); in addition, the study tests the relationship between digital transforming capability and firm performance. The results validate the proposed theoretical framework. In addition to proposing relevant microfoundations of the digital transforming capability, we advance knowledge on the performance effects of those microfoundations.Originality/valueThe paper contributes to advancing the understanding of the digital transformation phenomenon by revealing the role of the primary components underlying the digital transforming capability. Yet the mechanisms by which the micro-level aspects are important for digital transformation and organisational outcomes are only suggested by anecdotal evidence. The paper also contributes to ongoing calls for further investigation to extend the understanding of the microfoundations of dynamic capabilities. Finally, by drawing on archival data, this study also contributes to calls to broaden the toolkit used in dynamic capabilities research.N/
Exploring the Critical Factors for Sustainable Product-service Systems Implementation and Diffusion in Developing Countries: An Analysis of two PSS Cases in Brazil
AbstractThis paper aims at exploring how some factors identified in the PSS and product/service innovation literature can hinder or foster sustainable PSS implementation in developing countries, since there is a lack of knowledge concerning the characteristics of PSS transition processes in different contexts. The identified factors were investigated empirically, through two PSS solutions located in an emerging economy. The main results demonstrated the role of some potential factors in supporting the implementation and diffusion of PSS solutions, especially those related to the involvement of multiple actors in the value creation and the social embeddedness. However, the role of those factors still need to be investigated in future works, since only two cases were analyzed in this research. Analyses of successful and unsuccessful PSS cases as well as the identification of other factors and characteristics of PSS implementation in different contexts are directions for further research
Trees and water: smallholder agroforestry on irrigated lands in Northern India
Trees / Populus deltoids / Agroforestry / Afforestation / Reforestation / Models / Water use / Water balance / Evapotranspiration / Precipitation / Remote sensing / Irrigation requirements / India
Whole genome sequence analysis indicates recent diversification of mammal-associated Campylobacter fetus and implicates a genetic factor associated with H2S production
cknowledgements We like to thank Emma Yee (U.S. Department of Agriculture) for the generation of sequence data, we thank James Bono (U.S. Department of Agriculture) for the generation of PacBio RS reads and thank Dr. Brian Brooks and Dr. John Devenish (Canadian Food Inspection Agency) for providing C. fetus strains and for critical review of this manuscript. Funding Publication charges for this article have been funded by Utrecht University, the Netherlands.Peer reviewedPublisher PD
Linear scaling between momentum and spin scattering in graphene
Spin transport in graphene carries the potential of a long spin diffusion
length at room temperature. However, extrinsic relaxation processes limit the
current experimental values to 1-2 um. We present Hanle spin precession
measurements in gated lateral spin valve devices in the low to high (up to
10^13 cm^-2) carrier density range of graphene. A linear scaling between the
spin diffusion length and the diffusion coefficient is observed. We measure
nearly identical spin- and charge diffusion coefficients indicating that
electron-electron interactions are relatively weak and transport is limited by
impurity potential scattering. When extrapolated to the maximum carrier
mobilities of 2x10^5 cm^2/Vs, our results predict that a considerable increase
in the spin diffusion length should be possible
Effect of Compton Scattering on the Electron Beam Dynamics at the ATF Damping Ring
Compton scattering provides one of the most promising scheme to obtain
polarized positrons for the next generation of -- colliders.
Moreover it is an attractive method to produce monochromatic high energy
polarized gammas for nuclear applications and X-rays for compact light sources.
In this framework a four-mirror Fabry-P\'erot cavity has been installed at the
Accelerator Test Facility (ATF - KEK, Tsukuba, Japan) and is used to produce an
intense flux of polarized gamma rays by Compton scattering
\cite{ipac-mightylaser}. For electrons at the ATF energy (1.28 GeV) Compton
scattering may result in a shorter lifetime due to the limited bucket
acceptance. We have implemented the effect of Compton scattering on a 2D
tracking code with a Monte-Carlo method. This code has been used to study the
longitudinal dynamics of the electron beam at the ATF damping ring, in
particular the evolution of the energy spread and the bunch length under
Compton scattering. The results obtained are presented and discussed. Possible
methods to observe the effect of Compton scattering on the ATF beam are
proposed
Do Spin-Offs Make the Academicsâ Heads Spin?: The Impacts of Spin-Off Companies on Their Parent Research Organisation
As public research organisations are increasingly driven by their national and regional governments to engage in knowledge transfer, they have started to support the creation of companies. These research based spin-off companies (RBSOs) often keep contacts with the research institutes they originate from. In this paper we present the results of a study of four research institutes within two universities and two non-university public research organisations (PROs) in the Netherlands. We show that research organisations have distinct motivations to support the creation of spin-off companies. In terms of resources RBSOs contribute, mostly in a modest way, to research activities by providing information, equipment and monetary resources. In particular, RBSOs are helpful for researchers competing for research grants that demand participation of industry. Furthermore, RBSOs may be seen as a proactive response by Dutch public research organisations to demands of economic relevance from their institutional environment. RBSOs enhance the prestige of their parent organisations and create legitimacy for public funds invested in PROs. At the same time, most RBSOs do not have a significant impact on the direction of the research conducted at the PROs
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